Patent Publication Number: US-6990490-B2

Title: Information management method and information management device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application a division and claims the benefit of priority under 35 USC §120 from U.S. application Ser. No. 09/984,715, filed Oct. 31, 2001 Now U.S. Pat. No. 6,766,321 and is based upon and claims the benefit of priority under 35 USC §119 from Japanese Patent Application No. 2000-333971, filed Oct. 31, 2000, the entire contents of which are incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to management of shared information that is shared among a plurality of users via a network, more specifically, the invention relates to an information management method for plural users to exchange shared information and an information management device that makes the most thereof. 
   2. Description of the Related Art 
   Conventionally, as one example of systems employed in information exchanges among plural users via a network, well known is (1) a system wherein accumulated information such as documents and the like accumulated on a database is maintained by plural users in collaboration, and updated contents, messages and the like added to this accumulated information are notified to certain users. 
   In a system for managing accumulated information like the (1), since editing existing accumulated information is the base of its operation, the contents of messages sent to users are limited to results of editing work or notices of messages, accordingly there has been a problem that a lively discussion is unlikely to happen around a certain topic of information as a base. 
   While, as another example, well known is (2) a system including a mailing list, a bulletin board system, and the like, wherein flow type communications in which a user sends a message and other users reply to it and messages are exchanged among users are supported. 
   Such a flow information oriented system as the (2) is employed for lively communications among users. For example, a familiar example of this type of system is a bulletin board system wherein discussions are made around the contents of a homepage on WWW of internet. In such systems in the prior art, however, when a large amount of flow information is registered at one time, users have to read all the information chips one after another in order to grasp the contents, which has been a problem with the prior art. In some of mailing lists and the like, volunteer users post summarized messages in response to messages that have so far show up there, nevertheless, such messages will end up to bury themselves in a huge amount of other messages as part of flow information. Difficulties in mediating discussions will lead to difficulties in bring discussions to a conclusion, and also lead to difficulties for new users to such systems to grasp the flow of discussions made so far there, which had been another problem in the prior art. 
   On the other hand, there is a demand for finely setting the scope where the respective items of information are shared, in consideration of sharing information in a specified organization. For example, there may be a case where it is intended that users who can participate in discussions in a mailing list should be limited to users belonging to a certain group, and at the same time, stock information obtained as results of discussions should be made public also to the outside of the group. 
   In the systems as the (1) and (2), many of them fail to provide a method to flexibly set whether or not to make public the information shared in a certain group to other users out of the group. 
   As mentioned above, in those systems conventionally employed for information exchanges among plural users via a network, it has been difficult to accumulate and manage the transitions of discussions through exchanging messages in correspondence with documents created, edited, and read in the discussions, by connecting flow information of messages to documents created as one fruit summarizing message contents, and accumulated documents and the like referred to in messages. 
   Consequently, for example, the work to summarize the contents of messages exchanged among plural users as flow information in a specific user group into a single document has been left to a volunteer user, who in creating such a document requires a great amount of labor to analyze and summarize all the transitions of flow information by himself, as a result, creation of a document as the result of discussions has been unlikely to be dame lively, which has been still another problem with the prior art. 
   Even in the environment where such problems as mentioned above have been solved in respective user groups, there is still a problem that exchanges among plural user groups cannot be made flexibly in making public worthy information obtained as the result of discussions by flow information in a user group consisting of specific participants and part of information now under discussions to the outside of the user group. That exchanges among plural user groups cannot be made flexibly may cause opinion exchanges about a topic that relates to plural groups not to be made easily, and even for discussions in each user group to be piled up. 
   Further, when there are plural user groups that exchange discussions on a specific topic, users who are going to participate in these groups find it difficult to know in which user group they should take part, as a consequence, the number of new users to user groups may not increase, leading to stagnation of discussions in user groups, which has been still other problem seen in the prior art. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention has been made in consideration of the problems in the prior art, accordingly, an object of the present invention is to provide an information management method and an information management device that enables, in an environment wherein, in plural user groups to discuss about a specific topic, documents and messages posted, updated, and referred to in discussions are managed in correspondence with transitions of discussions by messages exchanged among users as members of each user groups as shared information of the user group, to flexibly conduct exchanges among plural user groups via this shared information, and to promote the participation of new users to respective user groups. 
   According to one aspect of the present invention, there is provided a document management method for, concerning the document that can be owned jointly by the respective users of the plural terminal devices via a network, renewing the document by reflecting an editing intention shown by each of the users while managing the renewal history of the document. The method comprises generating a community in which an access authority is controlled; generating a plurality of message trees in the community, each of which accepts a message from users using the terminal devices, the message being in reply to the other message in the message tree; editing a plurality of documents each of which is associated with one of the message trees; generating additive message subjected to a change within one of the documents, the additive message being written into the corresponding message tree by one of the users who made the change; generating a bidirectional reference between the additive message and the corresponding document; and searching for one of the documents as an instructive knowledge for at least one of the users in the community, wherein the corresponding massage tree is referred to by the one of users using the found document. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       FIG. 1  is a diagram showing a structural example of an entire information shared system for realizing a document management method according to a embodiment of the present invention. 
       FIG. 2  is a diagram showing a structure of functions of a server device. 
       FIG. 3  is a diagram showing a structure of functions of a community information management portion. 
       FIG. 4  is a diagram showing a structure of functions of a document management device. 
       FIG. 5  is a flow chart for explaining processing actions of a message analysis portion. 
       FIG. 6  is a flow chart for explaining processing actions of an update information extraction portion. 
       FIG. 7  is a flow chart for explaining processing actions at the moment when a message not including document operation data is created. 
       FIG. 8  is a flow chart for explaining processing actions at the moment when a message including document operation data is created. 
       FIG. 9  is a flow chart for explaining document monitoring processing actions. 
       FIG. 10  is a diagram for explaining processing actions at the moment when a message including document operation data is created. 
       FIG. 11  is a diagram for explaining document monitoring processing actions. 
       FIG. 12  is a diagram showing an example of a check table used for judging possibility of combination of document identification information and kinds of editing operation. 
       FIG. 13  is a diagram for explaining the relations between documents and message trees. 
       FIGS. 14A ,  14 B and  14 C are diagrams for explaining structural methods of message trees. 
       FIG. 15  is a diagram for explaining a structure of a document management device and processing actions thereof in the case of newly creating a document from all or part of messages configuring one message tree. 
       FIG. 16  is a diagram showing a data structure of a message to be accumulated in a message accumulation portion. 
       FIG. 17  is a diagram showing a data structure of a document to be accumulated in a document accumulation portion. 
       FIG. 18  is a diagram showing an example of control data of shared information to be accumulated in an information management portion. 
       FIG. 19  is a diagram showing an example of community information to be accumulated in a community information accumulation portion. 
       FIG. 20  is a diagram showing an example of user information to be accumulated in a user information accumulation portion. 
       FIG. 21  is a view showing a display example of an information search screen. 
       FIG. 22  is a view showing a display example of a search result display screen. 
       FIG. 23  is a view showing a display example of a display screen to display a message. 
       FIG. 24  is a view showing a display example of a display screen to display a document. 
       FIG. 25  is a view showing a display example of a message registration screen. 
       FIG. 26  is a flow chart for explaining community search processing actions. 
       FIG. 27  is a view showing a display example of a community search result display screen. 
       FIG. 28  is a view showing a display example for informing a manager of a non-public community or a membership community of existence of a user as a candidate participating in the community. 
       FIG. 29  is a flow chart for explaining shared information search processing actions. 
       FIG. 30  is a diagram showing a functional structure of a server device according to a second embodiment of the present invention. 
       FIG. 31  is a diagram showing another example of user information accumulated in a user information accumulation portion. 
       FIG. 32  is a flow chart for explaining processing actions to calculate contribution degree of a user to a certain document. 
       FIG. 33  is a flow chart for explaining processing actions for obtaining contribution degree of a user to a community. 
       FIG. 34  is a view showing another example of a message registration screen. 
       FIG. 35  is a view showing still another example of a message registration screen. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Embodiments of the present invention will be illustrated by reference to the drawings below. 
   [First Embodiment] 
   (1) Structure 
     FIG. 1  is a schematic diagram showing a structural example of an entire information shared system according to the present invention. A user, by using a user terminal  40 , communicates with a computer as a server device  1  (hereafter referred to as document management device) via a communication network  41 , and thereby enjoys information services according to the present invention. 
   The server device  1  is comprised of a computer communicably connected with plural user terminals  40  via the communication network  41 , and the user terminals  40  communicate with this server device  1 , thereby enable for users to participate in discussions in a user group where users discuss about specific topics (hereafter referred to as community), or discussions in other communities. That is, for example, as in a bulletin board system, by use of an input screen that the server device  1  provides to the user terminals  40 , a user creates a message or a message and document, and designates the community to which the user belongs and registers it to the server device  1  (this is referred to also as “post”), then users as members of the community may read the message and document via the server device  1 . Or, as in a mailing list, such a message and document may be forwarded to respective members of the community via the server device  1 . 
   In the server device  1 , posted messages, and documents created, updated, and referred to in discussions are corresponded to the transitions of discussions that users of the members of each community exchange via the communication network  41 , and thereby these messages and documents are managed as shared information of respective members of the community. 
   With respect of shared information registered and managed in the server device  1  per community, all the shared information of a community may be presented to the members of the same community, while to members of other communities, only shared information of a predetermined range may be presented. Preferably, documents registered in each community may be presented to members of other communities. 
   When a user posts a message created by use of the input screen provided by the server device  1 , the user search for a community suitable for posting the message, and designates it. 
   Documents managed as shared information per community include, for example, web pages and the like. To these documents, users can not edit or update anything by use of the server device  1 , therefore, herein these are referred to as external documents (on the other hand, those documents that can be created and edited and updated by use of the server device  1  are referred to as internal documents in many cases). However, even these external documents may be objectives of monitoring of the server device  1 . As shown in  FIG. 1 , files of external documents (external document files  42 ) should be stored in another server device comprising a specific computer that may be accessed from the server device  1  via the communication network  41 . The server device  1  can monitor whether designated external documents have been updated by a person having editing authority or not. Documents to be objectives of monitoring are not limited to external documents, but may be internal documents. 
     FIG. 2  is a diagram showing a structure of functions of a server device  1 , which comprises a community information management portion  2 , a Inter-community information management portion  3 , an information search and presenting portion  4 , a user information accumulation portion  5 , a user information management portion  6 , an input and output portion  7 , and a community information accumulation portion  8 . 
   The community information management portion  2  is for totally managing plural communities according to community information accumulated in the community information accumulation portion  8  (attributes of respective communities, including community names, participating users, scopes of information publication, etc.). 
   When a search request is input by a user through the input and output portion  7 , the Inter-community information management portion  3  gives the search request to the community information management portion  2  as input, and sends a search result to the information search and presenting portion  4  according to the publication scope of information fed back. 
     FIG. 3  is a schematic diagram showing a structure of functions of a community information management portion  2 , which comprises a message accumulation portion  9 , a document accumulation portion  10 , an information management portion  11 , and an information presenting portion  12 . 
   The message accumulation portion  9  accumulates messages created by users, and these messages may be plain texts, or document data describing personal knowledge and know-how chips, computer software, audio information, or image information. Comments accumulated herein cannot be edited or updated. 
   The document accumulation portion  10  accumulates document data. This document data includes computer software, audio information, and image information. Documents accumulated herein may be edited and updated by plural users. Documents may be documents summarizing plural messages accumulated in the message accumulation portion  9 . 
   The information control portion  11  manages the relations between the messages accumulated in the message accumulation portion  9  and the documents accumulated in the document accumulation portion  10 , and document update history information. 
   The information presenting portion  12  sends an information search request from a user to the information management portion  11 , and also displays information output by the information management portion  11 . 
   (2) Document Management per Community 
   Next messages and documents to be accumulated in the message accumulation portion  9  and the document accumulation portion  10  are explained hereinafter. 
     FIG. 4  is a diagram showing a structure of functions of a document management device  13  for accumulating messages and documents to the message accumulation portion  9  and the document accumulation portion  10  in  FIG. 3 . By the way, a message data storage portion  62  corresponds to the message accumulation portion  9  in  FIG. 3 , while a document data storage portion  63  corresponds to the document accumulation portion  10  in  FIG. 3 . Interactions between the document management device  13  and users are made through the input and output portion  7  in  FIG. 2 . 
   In  FIG. 4 , a message input portion  51  provides a specific input screen to the user terminals  40 , and via this input screen, users input messages for creating and editing documents and messages of only message texts (message texts). Comments created by users included, messages texts, and (in the case of reply messages to existing messages) identification information of existing messages users can refer to (reference message ID), and in the case accompanied with document editing operation, document identification information of editing objectives, kinds of editing operations, and editing data are included. Kinds of editing operations, document identification information, and editing data are collectively referred to as document operation data. 
   The kinds of editing operations includes operations for document editing preset (provided from the document management device) such as “new creation”, “replacement”, “addition”, “deletion” and the like, and in carrying out a document editing operation, a user selects one of these on the input screen provided from the message input portion  51 . 
   The document identification information is information comprising codes to specify sharable documents via the communication network  41 , for example, numeric and code strings given by a specified rule in the document management device, or web page URL, a pass name on a file system, and the like. 
   The editing data is data to be applicable to a document of editing objective, and means the editing data corresponding to the selected kinds of editing operations, i.e., a newly created document in the case where the kind of editing operation is “new creation”, a replacement position and replaced document in the case where the kind of editing operation is “replacement”, data to be added to editing objective document and addition position in the case where the kind of editing operation is “addition”, while deletion position (document to be deleted may be included) in the case where the kind of editing operation is “deletion”. 
   The message analysis portion  52 , when document editing data is included in messages input for the input portion  51 , checks the kind of editing operation in this document editing data and the combination of document identification information and editing data and their contents. Checked document operation data is stored into and managed by the message data storage portion  62 , and also sent to the document editing portion  53 . When document operation data is not included in the messages input from the input portion  51 , input messages are transferred to the message insertion portion  59  as messages to be placed. 
   By the way, “insertion” herein means, for example, as writing a message on a bulletin board in a bulletin board system, writing a message to be placed into the message data storage portion  62  so that can referred to such a message on the user terminals  40  of users as members of community, or on the user terminals  40  of unspecified number of the general users. This may be referred to registering (or posting) a message to a community. 
   In the document editing portion  53 , editing operation using editing data is carried out on document designated by the document identification information, according to the document operation data (for example, the latest one stored in the document data storage portion  63 ). For example, when the document identification information is not yet designated, and the kind of editing operation is “new creation”, document identification information is newly issued according to a specified rule. When document identification information is designated, and the kind of editing operation is “replacement”, a text at the replacement position included in editing data is replaced by replacement text included in editing data, thereby document editing is carried out. When document identification information is designated, and the kind of editing operation is “addition”, an additional text included in editing data is added to the additional position in the editing data to the designated document, thereby document editing is carried out. When document identification information is designated, and the kind of editing operation is “deletion”, to the designated document, a text to be deleted is deleted from the deletion position included in editing data, thereby document editing is carried out. 
   The document revision management portion  54  is started from the document editing portion  53 , after document edition in the document editing portion  53 , and additionally creates a new document revision information corresponding to the document identification information designated at the start. That is, the document revision management portion gives to a document edited in the document editing portion  53  a revision number showing how many times the edited document has been revised (for example, when the third editing has been made, revision number “ 3 ” is given, while, when a document is newly created, revision number “ 0 ” is given), and for example, a document file of this latest revision number is created in the folder corresponding to the document identification information created in the document data storage portion  63 , and the edited document and editing time are saved, thereby, a new document revision information is additionally created. When the document monitoring portion  55  detects that a document of monitoring objective (including external documents) is updated, the document revision management portion  54  is started and additionally creates a new document revision information corresponding to the document identification information designated at the start. That is, to the updated document of monitoring objective, the document revision management portion gives to the updated document of monitoring objective a revision number showing how many times the updated document of monitoring objective has been updated, and for example, creates a document file of this latest revision number as document revision information in the folder corresponding to the document identification information created in the document data storage portion  63 , and copies the updated document of monitoring objective in this folder, and also saves the time of update. 
   In the document monitoring portion  55 , to document of document identification information (including external documents) designated by message created by a user as monitoring objective, periodically or irregularly, document of monitoring objective is accesses, and the current contents of the document and the contents of document of the latest (having the largest revision number) document revision information contained in the document data storage portion  63  obtained via the document revision management portion  54  are compared, and when difference is detected (when update is detected), the document monitoring portion makes the document revision management portion  54  create the latest revision information of the document of monitoring objective. 
   The update information extraction portion  56  is started after the document revision management portion  54  creates document revision information, and extracts, from document revision information transferred at the start (document revision information of the latest revision number and document revision information of the one before the latest revision number), update information comprising difference data between the latest document (including external documents) stored in the document data storage portion  63  and the document before that and kinds of document operations (as same as editing operation, new creation, addition, correction, deletion, etc.). At extraction of difference data, it is effective to use a difference detection program of line unit or character unit, for example, like diff command of UNIX. 
   The message generation portion  58 , when the document monitoring portion  55  detects update of document of monitoring objective, creates message text, on the basis of update information of this document of monitoring objective extracted by the update information extraction portion  56 , and obtains reference message ID, thereafter, transfers this created message text and reference message ID to the message synthesis portion  57 . 
   The message synthesis portion  57  synthesizes message text and reference message ID input in the message input portion  51 , message text and reference message ID generated by the message generation portion  58 , other document identification information, update information and the like, thereby creates insertion message. 
   The message insertion portion  59  issues message ID to insertion message, and further, when there exist insertion message and message ID, and document of editing objective, then corresponds the document identification information, revision number of document updated by the message or, revision number of the document at which the insertion message has been created when document update was detected, and the like, and stores into and managed in the message data storage portion  62 , and also manages a series of message groups linked by reply relation by the reference message ID in insertion message. In this case, in principle, message without message ID is of a tree structure as “root”. 
   The message display portion  60  displays insertion message designated by message ID and message tree including insertion message to the user terminals  40 . 
   The document display portion  61  displays document of document identification information designated from the user terminal  40 . At this moment, access information to message is also displayed so that message of editing operation to message (insertion message) should be referred to. 
   The message data storage portion  62  stores message input from the message input portion  51  (including message text, document operation data, etc.), insertion message, and the like. 
   The document data storage portion  63  stores (registers) document revision information of all document identification information, in correspondence with document identification information. By the way, existing document being edited and updated by message registered in a certain community by a user, and new document revision information being generated, and stored in this document data storage portion  63 , may be referred to as document being registered together with message. 
   Next, in reference with the flow chart shown in  FIG. 5 , the processing actions of the message analysis portion  52  in  FIG. 3  will be explained hereinafter. 
   With respect to message data input from the message input portion  51 , first at step S 11 , it is judged whether or not there is designation of kind of editing operation in document operation data, if not, message is only message text, or message text and reference message ID, therefore, it is transferred as insertion message to the message insertion portion  59 . 
   On the other hand, if there is designation of kind of editing operation, in step S 12 , the combination of kind of editing operation and document identification information is collated with a check table. As an example of check table here, such one as shown in  FIG. 12  is considered. Explanations on  FIG. 12  will be made in detail later herein. 
   Next, in step S 13 , when it is judged as an effective combination, then document operation data is sent to the document editing portion  53 , while, it is judged as invalid, the procedure goes on to step S 14 , wherein a warning is given, and the message input portion  51  urges user to input once again. 
   Next, in reference with the flow chart shown in  FIG. 6 , the processing actions of the update information extraction portion  56  in  FIG. 4  will be explained hereinafter. 
   When the document revision information of the latest revision number and that of the revision number before the latest are obtained from the document revision management portion  54 , in step S 21 , difference between the documents of those two revision numbers is detected. In step S 22 , the kind of document operation showing which part of the documents have been changed in what manner is judged from the difference data detected, and thereby, difference information comprising difference data and determined kind of document operation is generated. For example, when there is document operation data, the kind of editing operations (one of new creation, addition, change, and deletion) and editing data may be employed as difference information, but when there is not document operation data or in the case of external documents, the kind of document operation is determined by comparison of documents before and after. 
   Next, in step S 23 , when message text is empty, the process goes on to the processing at the message generation portion  58 , while, when there is message text created by a user, the process goes on to the processing at the message synthesis portion  57 . 
   Next, in reference to the flow chart shown in  FIG. 7 , the outline of the processing actions in the case where message not including document operation data is created (processing actions from message creation to message display) is explained. This is almost same as the flow of processing actions from creation of new message and replay message to the display thereof in an information exchange system such as a mailing list and a bulletin board system. First, in step S 31 , message created by a user is input from the user terminal  40  to the message input portion  51 , and in step S 32 , when the message analysis portion  52  judges that there is not document operation data in this message, then the process goes on to the processing at the message insertion portion  59  at step S 33 , wherein it is considered as only message text, or as a insertion message comprising message text and reference message ID, and message ID is given to message, and it is stored into the message data storage portion  52 . In step S 34 , at request from user, this insertion message is displayed on the user terminal  40 . 
   Next, in reference to the flow chart shown in  FIG. 8  and  FIG. 10 , the processing actions in the case to edit document from message will be explained. 
   In  FIG. 10 , a message tree  100  shows part of message trees of messages (insertion messages identified by message ID) exchanged among users as members of a certain group (community) where users can participate in discussions. Herein a message tree means a series of message groups connected by replay relations. A message tree is a tree structure having message of sent side as parent node, and message of replying side as child node thereof. Reference message ID that a certain message has means ID of original message that the message replies. For example, in the message tree  100 , message  102  is a replay to message  101 , and reference message ID that the message  102  has is same as message ID that the message  101  has. 
   Herein, the case where there are only  3 , i.e., messages  101 ,  102 , and  103  in the message tree  100  is supposed, and the case to create a new message as a reply message in response to the message  102  is explained. 
   First, in step S 41  in  FIG. 8 , a user creates message from the user terminal  40 , that is user creates message text and designates reference message ID, and in following step S 42 , document operation data is added. Comment created in the manner corresponds to created message  110  in  FIG. 10 . 
   In step S 43  in  FIG. 8 , the created message  110  is analyzed in the message analysis portion  52 , and whether there is reference message ID or not, whether document operation data is integrated or not and the like are checked. 
   In  FIG. 10 , the reference message ID in the created message  110  is one where message  102  is designated, and this created message  110  further comprises message text  112 , and document operation data  120 . The document operation data  120  comprises editing operation kind  121 , document identification information  122 , and editing data  123 . The editing operation kind is one that user has selected among preset editing operation kinds such as “new creation”, “replacement”, “addition”, “deletion” and the like. Document identification information need not to be specified in the case of “new creation”, and system will give a new document identification information according to a specific rule. 
   In step S 44  in  FIG. 8 , the document editing portion  13  actually carries out document editing, on the basis of given document operation data. In  FIG. 10 , to document  130  that document identification information in the created message  110  points out, the editing operation kind  121  and the editing data  123  given by document operation data are applied. 
   Next, in step S 45 , the document revision management portion  54  additionally creates the latest document revision information of document corresponding to the document identification information  122 . That is, in  FIG. 10 , as document information  140  to which a new revision number (herein, for example, one edited for the third time (revision number “ 3 ”), to de described “R 3 ”) is given, the document edited by the document editing portion  13  is stored into the document data storage portion  63 . 
   Further, in step S 46 , in the update information extraction portion  56 , the contents of document of the latest revision number of the document designated by document identification information and the contents of document of the revision number before the latest are compared, thereby update information is extracted. 
   In  FIG. 10 , from document revision information  140  of “R 3 ” and document revision information of “R 2 ”, document data before and after editing are obtained, and data are compared, thereby update information  150  is obtained. 
   Update information is information comprising text showing update position and document operation kind (update condition), for example, “The following portion has been added to part of document”, and in this case, part of sentence actually added. 
   In step S 47  in  FIG. 8 , at least message text and update information are synthesized to create insertion message. In  FIG. 10 , this corresponds to creation of insertion message  160  comprising reference message ID  111  in the created message  110  and message text  112 , document identification information  122  and update information  150 . 
   In step S 48 , message ID is given to the insertion message  160  in the message insertion portion  59 , and the insertion message  160  is stored into the message data storage portion  62 , as message corresponding to the message  104  that is child node of the message  102  on the message tree  100  in  FIG. 10 . 
   Finally, in step S 49 , at request from a user, the message  104  is displayed as one of message groups whose replay relations are managed by the message tree  100  in  FIG. 10 . 
   Next, in reference with the flow chart shown in  FIG. 9  and  FIG. 11 , document monitoring processing actions are explained hereinafter. 
   In step S 51  in  FIG. 9 , the document monitoring portion  55  judges whether or not it is now the timing for checking document update of documents (including external documents). With respect to the document to be objective of document monitoring, regularly or irregularly (for example, at instruction from a user), document update is checked. In  FIG. 11 , it is shown that document  230  pointed out by document identification information  213  designated in existing created message  201  created in the past and stored in the message data storage portion  62  is under monitoring by the document management device. 
   Next, in step S 52 , the document monitoring portion  55  compares the current contents of document of monitoring objective and the contents of document of the latest revision number of document of the monitoring objective. This, in  FIG. 11 , corresponds to that the contents of the document  230  are compared with the document revision information  240  of the latest revision number (“R 2 ”) of the document  230  stored so far. 
   In step S 53 , it is judged whether or not there is difference between the current contents of the document  230  of monitoring objective and the document of the latest revision number of the document of monitoring objective, and if there is difference, the process goes on to step S 54 , wherein the latest document revision information of document of monitoring objective is added by the document revision management portion  54 . In  FIG. 11 , this corresponds to that the current contents of the document  230  of monitoring objective is stored into the document data storage portion  63  as document revision information  241  of the latest revision number (“R 3 ”). When the revision number is updated, in step S 55 , update information  250  is created from difference between the new and old document revision information (of “R 2 ” and “R 3 ”) by the update information extraction portion  56 . 
   Next, in step S 56 , the message generation portion  58  generates reference message ID  251  and message text  252  from the update information  250 . In generation of reference message ID, for example, when the document  230  has been edited or updated lastly in the message tree where the document  230  is objective of editing and monitoring, used or created latest message (in  FIG. 11 , the message  202  on the message tree  200 ) is made as reference message. As created message text, for example, extraction of texts such as document identification information, document title, name of one who updates, and “addition”, “correction”, “deletion” and the like in the update information  250  is used. 
   Next, in step S 57 , the message synthesis portion  57  synthesizes insertion message from message text and update information and the like. In  FIG. 11 , by use of the document identification information  213 , reference message ID  251 , message text  252 , and update information  250  of the existing created message  201 , insertion message  260  is synthesized, which corresponds to that the message  204  is generated in the message tree  200 . 
   In step S 58 , the message insertion portion  59  gives message ID to the insertion message  260 , and stores it into the message data storage portion  62 , as message corresponding to the message  204  that is child node of the message  202  on the message tree  200  in  FIG. 11 . 
   Finally, in step S 59 , at request from user, the message  204  is displayed as one of message groups whose replay relations are managed by the message tree  200  in  FIG. 11 . 
     FIG. 12  shows an example of a check table used for judging possibility of combination of document identification information and kinds of editing operation in the message analysis portion  52 . 
   As document identification information, besides number issued on the basis of a specific rule in document management device, for example, URL of web page on Internet may be given. In the case of external documents to which such an URL is given, and when the document cannot be edited from the document management device, only document monitoring is enabled, and operations such as replacement or addition of document contents and the like are disabled. 
   According to the check table in  FIG. 12 , when the editing operation kind is “new creation”, when there is not designation of document identification information, and when the same document identification information as document of editing and monitoring objective in another message tree than the message tree that can be identified by reference message ID included in created message, or existing document as external document is designated, document monitoring is enabled, especially in the latter case, if external document that cannot be edited from the document management device is designated, start of document monitoring by the document monitoring portion  55  is meant. When the editing operation kind is “replacement” or “addition”, only when document identification information of document of editing and monitoring objective in message tree that can be identified by reference message ID included in created message, it is enabled. Further, when the editing operation kind is “deletion”, only when document identification information of document of editing and monitoring objective in the same message tree as message tree that can be identified by reference message ID included in created message or another message is designated, it is enabled, especially, in the latter case, if external document that cannot be edited from the document management device is designated, end of document monitoring by the document monitoring portion  55  is meant. 
     FIG. 13  is a diagram showing relations between documents and message trees. It is supposed that by exchanging messages among users as members of a certain group (community),  3  message tress  311 ,  312 , and  313  have been created. In the case of the message tree  311 , only the document  321  is the objective of editing and monitoring, and in the message tree  312 , there is no document to become objective of editing and monitoring, and it is structured by only message texts. In the message tree  313 ,  2  documents, i.e., document  323  and document  322  are objectives of editing and monitoring. Not limited to the cases, for example, message tree  13  can edit and monitor the document  321  that is objective of editing and monitoring by the other message tree  311 . 
   By designating document identification information in each message configuring message tree, document designated by the message tree may be objective of editing and monitoring, however, if this is permitted without limitation, history management of document editing and updates by the message tree, and the flow of discussions by the message text may be complicated. Therefore, it is prescribed that at most one document (as monitoring objective or as editing objective) should cope with in each message tree, thereby, it is possible to make clear the history management of transitions of document editing and updates by the message tree and the flow of discussions by the message text. 
   Next, the method to configure message tree in the message insertion portion  59  is explained hereinafter. As mentioned previously, there are the case when document is edited and updated by message, and the case when document is directly updated without message, and thereafter by document monitoring, message to correspond to the update is created. There are messages that do not include document editing operation, and are only message texts. 
   That is, as shown in  FIG. 14A , when document D 1  is newly created by creating message C 10 , message tree C 1  is newly created. As shown in  FIG. 14B , in the case where as reply to existing message C 10 , message C 11  (with the message ID of the message C 10  as reference message ID) is created, and the document D 1  is edited by this message C 11 , the message C 11  is made as child node leading to the message C 11 . Further, as shown  FIG. 14C , when message C 13  do not include document operation data, but is message created as reply to message C 11  (wherein reference message ID is message ID of the message C 11 ), it is made as child node leading to the message C 11 . 
   As mentioned above, when to edit document from message, user can determine message as reply, i.e., reference message ID, however, when to create message by document monitoring, it is necessary for the document management device to determine reference message ID. That is, in  FIG. 14C , when document D 1  is directly edited by a third party, this update is detected by the document monitoring portion  55 , reference message ID of message C 14  created as shown in  FIG. 9 , is made as message ID of the latest message (for example, message C 11  herein) used or created, when document D 1  has been edited or updated last in message tree where document D 1  is editing and monitoring objective, and message C 14  is made as child node leading to message C 11  (reply to message C 11 ). 
   As mentioned formerly, in the message data storage portion  62 , for example, with respect to one document update, plural message groups in reply relations are managed and stored by message tree, but among message trees, there are some comprising only message texts not relating to document editing. In these message trees too, since they are linked by replay relations, it is supposed that some discussion may be processes in each message text. Therefore, it is useful to create one document by summarizing all or part of message texts that configure a certain message tree, or to create editing data corresponding to documents as editing objectives of the message tree. 
     FIG. 15  is a diagram showing important portion of a structure of a document management device in such a case. Herein it is supposed that message tree  70  comprising only message texts, for example without document of editing objective, contained in the message data storage portion  62  is designated. 
   Comment text of each message (for insertion) that configures this message tree  70  is input to the message summary portion  65 . In the message summary portion  62 , process to summarize plural message texts into one document is carried out, for example, by use of an art disclosed in Japanese Patent Application KOKAI Publication No. 2000-112980. As a result, obtained document is sent to the document editing data creation portion  66 . In the document editing data creation portion  66 , document sent from the message summary portion  65  is handled as editing data, and to this editing data, “new creation” as the kind of editing operation is given, and document editing data for sending it to the document editing portion  53  is created, and the created document editing data is transferred to the document editing portion  53 . The processing after this is same as mentioned previously. 
   As described heretofore, when messages (including messages including document editing data) are posted (registered) from members of community per community, if there are newly created, updated documents based on such messages, such documents are registered as document revision information too, as a result, it is possible to correspond messages and documents (including newly created documents, updated documents) and thereby manage them, and also to manage transitions of discussions by message by message tree. 
   Documents to be managed as document revision information (newly created documents, updated documents) are always corresponded to messages, while, some of messages do not include document operation data, therefore they may be not corresponded to documents. 
   (3) Comment, Document, Shared Information Management Data, Community Information, User Information 
   An example of messages accumulated in the message accumulation potion  9  and documents accumulated in the document accumulation portion  10  (document revision information) as mentioned above is shown in  FIG. 16  and  FIG. 17 . 
   In  FIG. 16 , to message  500 , message ID  501  for identifying the message is given, and the message  500  comprises header information such as message title, user ID of user who has created thereof, date and time of creation, community ID of posted message, and the like, and main body information such as text as message text, document identification information of document edited, created by the message (herein, for example, file name, URL), reference message ID of the message, and the like. 
   In  FIG. 17 , document (concretely, document revision information)  520  has document identification information  521  for identifying the document, and consists of header information such as document title, editor of the document, date and time of editing, community ID of the document, revision number and the like, and main body information such as document text and the like. 
     FIG. 18  is a diagram showing an example of control data of shared information to be accumulated in an information management portion  11 . This management data  540  relates to, for example, one document to be identified by document identification information, and corresponds and manages community ID of the community to which the document belongs (where the document is shared information), and message ID of messages related to creation, editing and update of the document (message ID of messages that configure message tree). Further, in the management data  540 , publication scope such as whether the document can be made public only to members in community to which the document belongs, in the scope of users to which the document can be made public, or, whether the document can be made public to other users or not is corresponded and managed. 
   In the management data  540 , the document publication scope is “within community”, which shows that this document may be made public only to the community where this document has been created (to which the document belongs). Besides this setting, fine settings such as “may be made public to all communities”, “may be made public to only specified community” and the like may be made. 
     FIG. 19  is a diagram showing an example of community information to be accumulated in a community information accumulation portion  8 . Community information is to manage each of plural communities, and as shown in community information  560  in  FIG. 19 , it manages each community by community ID  561  as identification information to identify each community, name of the community, user identification information (manager ID) as manager, date and time of community creation, publicity degree of community, user ID of user as member of the community, publicity degree of message as shared information of the community to outside, document identification information of document created and updated in the community (shared information of the community), and log file name to accumulate community use history (for example, manager log information to be described later herein) and the like. 
   In the community information  560 , the publicity degree of community appears as “membership system”. This means that “the existence of the community is made public to outside users, but only users permitted as members of the community by manager can post messages to the community.” Besides this, as publicity degree, “non public” that means “the existence of the community is not made public to outside”, “public” that means accessible for all users, “public to organization” that means “users belonging to an organization can access” and the like may be set. 
   By the way, as in the community information  560  in  FIG. 19 , with respect to community of “membership system”, a list of user ID of users participating in the community by posting current message is described in an attribute called “member”. In the case of community of “public”, when a certain user posts message or document to the community, he becomes a member of the community, therefore, user ID of the user is added to the attribute “member” every time. 
     FIG. 20  is a diagram showing an example of user information to be accumulated in a user information accumulation portion  5 . The user information is for managing all the users in information shared system. In  FIG. 20 , user information  600  comprises user ID  601  for identifying each of all users in information shared system, name and belonging of the user, mail address, log file name for accumulating personal system use history and the like. 
   (4) Screen Display Examples 
     FIG. 21  is a view showing a display example of an information search screen provided from the input and output portion  7  to the user terminal  40 , and shows an display example at the user terminal  40 . 
   In  FIG. 21 , an information search screen  620  is for searching for shared information (herein, only documents) to meet user requirements and communities, on the basis of search string input in a search string input area  621 . As shown in  FIG. 21 , the information search screen  620  comprises the search string input area  621 , a search execution instruction button (search button)  624 , and a display area  623  of list of communities made public among existing communities in the information shared system. 
   When a user inputs a desired search string into the search string input area  621 , and presses the search button  624 , the server device  1  starts searching, and searches for documents similar to the search string, and displays the results of search on the user terminal  40  from which request has come. It also searches for and displays communities where discussions of a field similar to the search string are being carried out. 
   By the way, documents managed as shared information in each community are, in principle, public documents that may be made public also to members of other communities. 
   The list of communities displayed in the display area  623  is displayed in classification into some categories (in  FIG. 21 , “project minutes of proceedings”, “living information”, and “miscellaneous”), however, the display method of the list is not specially limited herein. 
     FIG. 22  is a view showing a display example of a search result display screen provided from the input and output portion  7  to the user terminal  40 , and shows a display example at the user terminal  40 . 
   In  FIG. 22 , the search result display screen  640  shows the search result when a natural language search string is input to the search string input area  621  in the information search screen  620  in  FIG. 21  and search has been executed. 
   The search string input display area  641  of the search result display screen  640  shows a search string that is input by a user to the search string input area  621  of the information search screen  620  in  FIG. 21 , while, looking at this search result display screen  640 , if user wants to carry out search once again by adding correction to the search string, user may input a new search string once again to this search string input display area  641 , and press the search button  644 . 
   In the search result display screen  640 , as search result, for example, a list  642  of communities similar to the input search string and a list  643  of documents similar to the input search string are displayed. 
   For example, when a desired community is selected from the list  642  of communities as the search result displayed in the search result display screen  640  in  FIG. 22 , if this user is a member of the selected community, a display screen  660  as shown in  FIG. 23  is provided from the input and output portion  7 , and at the same time, the list of messages in the selected community is displayed on a display area  661 . 
   The display area  661  of the display screen  660  in  FIG. 23  is output in response to request to browse especially messages among shared information in a desired community, and the list of messages in a community, for example, “strategic patent project” is displayed in message tree style. 
   When a desired message is selected from the message tree displayed on the display area  661 , the selected message is displayed on a display area  662  of the display screen  660 . In  FIG. 23 , it is shown that the message with title “reply: patent specification first draft” that has been selected from the message tree displayed in the display area  661  is displayed on a display area  663 . When to display message, this message text is mainly displayed. By the way, when there are documents related to the displayed message, links to such documents are displayed. In  FIG. 23 , when the link display portion  663  is selected by a mouse or so, as shown in  FIG. 24 , a display screen  680  is provided from the input and output portion  71 , and at the same time, the documents are displayed on a display area  681 . 
   The display area  681  of the display screen  680  in  FIG. 24  is output in response to request for user to browse especially documents among shared information in community, and header information  682  including the title of the document, editor of the document, date and time of editing, community ID of the document, revision number, publicity scope of the document and the like, and document text  683  is displayed. 
   In the display screen  680  in  FIG. 24 , further in a display area  685 , the list of messages relating to creation, edition, update of document displayed on the display area  683  is displayed in message tree style. Thereby, it is possible for the user who browses the document displayed on the display area  685  to browse in what transition the document has been created. 
   By the way, users who can browse the display screen showing the list of messages and documents as shown in  FIG. 23  and  FIG. 24  are, in principle, members of the community where the messages and documents are registered. 
     FIG. 25  is a view showing a display example of a message registration screen that is provided from the input and output portion  7  to the user terminal  40 , and shows the display example on the user terminal  40 . 
   Herein a message registration screen is shown wherein user creates (newly creates) a new document summarizing message texts of plural messages configuring message tree and registers it. 
   A message registration screen shown in  FIG. 25  mainly comprises a message text input area  701 , a document text input area  702 , and a message display area  703 . 
   In a message registration screen  700  in  FIG. 25 , first, user selects message tree to be processing objective, and make it displayed on the message display area  703 . In this message display area  703 , not only message tree but also contents (at least message texts) of messages selected from the message tree are displayed. In reference to the contents of the messages displayed on this message display area  703 , user inputs text body of document into the document text input area  702 . The message text input area  701  is, for example, message text concerning document created, and used for creating message to notify members of community of creation of document. 
   Document may summarized manually and created, in reference to existing messages as mentioned above, while, when there are many message to refer to, summarizing manually may be complicated. In this case, by use of, for example, such an art as disclosed in Japanese Patent Application KOKAI Publication No. 2000-112980, it is possible to summarize plural message texts into one document. For this purpose, the document message registration screen  700  is equipped with an instruction button (auto summary button)  704  for automatically summarize message texts in messages configuring the message tree displayed and selected on the message display area  703 . By pressing this button  704 , in the community information management portion  2 , by the structure shown in  FIG. 15 , it is available to automatically create a summary of selected messages. The document created after automatic summary is displayed on the document display area  702 . 
   The message registration screen shown in  FIG. 25  is used for not only creating document summarizing messages displayed on the message display area  703 , but also creating message as reply to message displayed on the message display area  703 , and also for creating and updating document corresponding to message. That is, message is input to the message text input area  701 , and document operation data is input to the document text input area  702 , and a posting destination search button  706  is selected by a mouse or the like, communities as posting destination of input message are searched. A desired one is selected among the list of communities displayed as result of search of posting destination, and specific operation is carried out, thereby the message input to this message registration screen  700  is posted to the selected community. 
     FIG. 34  is a view showing another example of a message registration screen, and is a message creation screen  400  for creating reply message to existing messages (insertion messages) not including especially document operation data. In  FIG. 34 , in input areas  402 ,  403  and  404 , titles as replay message, reference message ID, and message text are input, and in this status, when the send button  410  is pressed, input data of this message creation screen is input as created message to the input portion  11 , and the processes after step S 32  in  FIG. 7  are carried out. 
   On the other hand, in the status shown in  FIG. 34 , when the button  406  displayed as “to document operation” is pressed, message creation screen accompanying document operation data as shown in  FIG. 35  can be started. 
     FIG. 35  is a view showing still another example of a message registration screen  420  for creating message accompanying document operation. Besides input to the input areas shown in  FIG. 34 , document identification information (document ID) as editing objective, editing operation kind, and editing data are input to the input areas  422 ,  425 , and  423 . At the moment when editing operation kind is input to the input area  425 , the list of editing operation kinds (“new creation”, “addition”, “replacement”, and “deletion”) are displayed in pull down menu style, and one selected among them is displayed on the input area  425 . 
   On the message registration screen shown in  FIG. 35 , for example, reference message ID, message text, document identification information to be editing objective, editing operation kind, and editing data are input, and the send button  428  is pressed, then the input data of this message registration screen is input as created message to the message input portion  51  via the input and output portion  7 , and the processes after step S 43  in  FIG. 8  are carried out. 
   By the way, in  FIG. 25 ,  FIG. 34 , and  FIG. 35 , areas to input community ID and user ID are not displayed, however, input areas for community ID and user ID may be included, or may be added automatically. 
   As mentioned heretofore, some screen display examples to be displayed on the user terminal  40  have been explained, however, the screens are not limited to the cases mentioned so far. Especially, in the message registration screen, any screen may be used, only when it enables to register message including document operation data for editing and updating document, or message of only message text to each community, to manage transitions of discussions by exchanges of messages by message tree per community, and to input information necessary for corresponding and managing documents (including updated documents) created, edited, or updated by messages on the message tree to the message. 
   (5) Search of Communities 
   In reference to the flow chart shown in  FIG. 26 , the processing actions of the Inter-community information management portion  3  to search for communities similar to search request input by users the processing actions to search for communities suitable for messages (or messages and documents) created by users will be explained hereinafter. 
   Community search request is sent to the server device  1  when the search screen  62  shown in  FIG. 21  is displayed, and search string is input in the search string input area  621  of this search screen  620 , and the search button  624  is pressed, and when the document message registration screen  700  shown in  FIG. 25  is displayed on the user terminal  40 , and message and document is input into this screen  700  (or when input is made by selecting existing (for example, already posted to any community) message and document), and the posting destination search button  706  is pressed. In search request in the former case, at least user ID and search string are included, while, in search request in the latter case, at least user ID and input message text and document text (hereinafter, message text and document text included in search request are referred to as search texts) are included. 
   The search string that is input to the search string input area  621  of the search screen  620  is a string wherein sentence of natural language or a word or plural words, or plural words combined by logic operators (AND, OR), and the like. 
   This search request (of community) is sent via the information search and presenting portion  4  to the Inter-community information management portion  3 . The Inter-community information management portion  3 , first, transfers search string, search sentence to the community information management portion  2 , and then searches for messages and documents similar to these to all the shared information of all the communities, and as a result, it creates a set of messages M 0  and a set of documents G 0  (steps S 301  and S 302 ). 
   By the way, in searching for messages and documents similar to search string and search sentence, for example, the art of “document search device” disclosed in Japanese Patent Application KOKAI Publication No. 6-231178 may be employed. That is, morpheme analysis, construction analysis, and semantic analysis of search string and search sentence included in search request are carried out, and meaningful related words from words extracted as the result are combined by use of logic operators, and thereby new search string is created. With respect to each of all the documents and messages managed as shared information per community, on the basis of morpheme analysis, construction analysis, and semantic analysis in the same manners as the, the number of character strings to match (meet) the newly created search string, or the number of sets of character strings is obtained from documents and messages, and documents and messages of over the threshold value at which the number has been preset are extracted as document and messages similar to search string and search sentence included in the search string. For making explanations easier, the number of character strings or sets of character strings to match the new search string is set as the value of similarity of documents and messages. By the way, the present invention does not intend to make a special limit to the method to search messages and documents similar search string. 
   Next, the Inter-community information management portion  3  receives the set of messages M 0  and the set of documents G 0  extracted as search results from the community information management portion  2 , and then sorts them per community, and male the total of similarities of messages and documents collected per community the similarity of community (step S 303 ). It generates a set of communities P where communities are placed in the order of similarity (step S 304 ). 
   By the way, in the explanation, in the similarity calculations for searching communities similar to search string and search sentence, similarity has been obtained by accumulating similarities of documents and messages similar to the search string and search sentence belonging to the community, however, the method is not limited to this, and there may be a method, for example, wherein word vector space of community is indexed in advance from messages, and similarity is calculated from the index. By the way, the present invention does not intend to make a special limit to the method to obtain the similarity of community. 
   To elements whose similarities are larger than a threshold value TH among the elements of the set of communities P, the following processing is carried out (steps S 306  and S 307 ). When the similarity of an element Pi of the i-th of P is larger than the threshold value TH, it is recorded to manager log information LPi of community Pi that search request including search string similar to the community, search sentence, and user ID has been input (step S 308 ). That is, at least, search string, search sentence, and user ID are recorded as the history of the search request. 
   If the community Pi is a public community, or a membership community to which the user who has made the search request belongs, the community Pi is added to search results Q (steps S 309  and S 310 ). 
   If the community Pi is a membership community, and the user who has made the search request does not belong to the community, the user ID of the user is added to he member candidate list UPi of the community Pi (steps S 311  and S 312 ). 
   The set of communities Q as the search result created by search processing on all the communities as shown above is sent to the information search and presenting portion  4 . For example, when search request is carried out from the search screen in  FIG. 21 , the information search and presenting portion  4  can display the list of communities  642  in the order of higher similarity to search string and search sentence, as shown in the search result screen  640  in  FIG. 22 . 
   When search request is carried out from the message registration screen in  FIG. 25 , the set of communities Q suitable for posting messages and documents created on this screen is displayed on the community search result display screen  720  as shown in  FIG. 27 . Of course, communities are displayed in the order of higher similarity to search sentence, i.e., created messages and documents. User selects a desired one among the list of communities, and selects the registration button  721  by a mouse or so, thereby the message input to this message registration screen  700  (message not including document operation data, or message including document operation data) is posted to the selected community. 
   By selecting a desired community from the community list display area  623  of the search screen  620  shown in  FIG. 21 , or by selecting a desired community from the community list  642  of the search result display screen  640  shown in  FIG. 22 , user gets in a status of access to the selected community, that is, he gets in the selected community, and in this status too, it is available to carry out search of communities as shown in  FIG. 26  by conducting a specified operation. In this case, when the community to which the user belongs is included in the set Q of communities obtained as the search results, the information search and presenting portion  4  displays communities by excluding the community,from the set Q of communities. 
   Now, as the result of the processing shown in  FIG. 26 , when a certain community Pi is a membership community, and further, when the member candidate list UPi is not empty, it can be judged that a user u belonging to UPi, though he is not a member of the current community, he is a user able to carry out search request relating to the contents discussed in the community Pi, and post (register) messages and documents relating to the contents discussed in the community Pi in other community. In such a case, promotion activities are available for the Inter-community information management portion  3  to notify (introduce) the existence of the user u to the manager of the community Pi, and in response to this, for the manager to send introduction message to the user u, and the like. 
     FIG. 28  is an example of screens provided from the input and output portion  7  to the user terminal  40  at the manager for notifying to manager of non public community or membership community the existence of the user as a participating candidate to the community. 
   In  FIG. 28 , in this display screen  740 , a list  741  of user whom the Inter-community information management portion  3  has judged appropriate to take part in the community is displayed, and a display area  743  of search string, document and message relating (at the moment of when the community is selected) to the community of the user selected on this user list  741 , and buttons  744  and  745  for instructing to invite the user selected from the list  742  and adding user forcibly to members are arranged. 
   By the way, in a display screen  749 , part of the information listed in the user information accumulated in the user accumulation portion  5  is displayed on the list  742 , however, for some reason (for example, when the user denies his personal information being made public, and the like), as shown in  FIG. 28 , part of information may be hidden. 
   The Inter-community information management portion  3  may analyze the manager log information LPi of a certain community Pi, and detect that many search requests similar to the contents discussed in the community Pi (search request data including search string, message, and document) are input. When there is not any document that can be presented as an answer to the set of these search requests in the community Pi (when there is not document having community ID of the community in the document accumulation portion  10  of the community information management portion  2 , there is such a document, but when it is non public to other users than members of the community), the Inter-community information management portion  3  may send a message to urge the manager of the community or the whole members to register a document to be an answer to the set of the search requests, or to make document public. 
   The Inter-community information management portion  3  may analyze the manager log information LPi of the community Pi, and detect that many shared information (messages and documents) similar to the contents discussed in the community Pi are registered in other communities. 
   For example, when search request has already been made with existing messages and documents posted (registered) in a certain community, since the history of the search request has been recorded in the log information LPi (for example, in messages and documents included in search request, as shown in  FIG. 16  and  FIG. 17 , community ID of registration destination is described in header information, therefore, by referring thereto), other communities whose contents of discussions are similar may be detected in easy manner. In such a case, the Inter-community information management portion  3  may send a message to respective managers of communities which are similar to the effect that the contents of discussions of communities are similar. 
   Further, when many search requests (more than the prescribed number) of the identical user u are recorded in the manager log information LPi of a certain community Pi, the Inter-community information management portion  3  may send to the manager of the community Pi a message to tell that the user u already exists. In response thereof, the manager may take measures to invite this user u to the community Pi. 
   (6) Search of Shared Information 
   In reference to the flow chart shown in  FIG. 29 , the search processing actions of the community information management portion  2  will be explained hereinafter. 
   First, the case is explained wherein a user selects a certain community, and search for shared information in status connecting to the community. When this user is a member of the community, all the shared information of the community can be presented, while, when the user is not a member of the community, in principle, only documents can be presented. By the way, shared information (messages and documents) of each community is designated whether to not to be presented to members of other communities (by management data of shared information as shown, for example, in  FIG. 18 ), documents may not be presented to users of other community. 
   By selecting a desired community from the community list display area  623  of the search screen  620  in  FIG. 21 , or by selecting a desired community from the community list  642  of the search result display screen  640  shown in  FIG. 22 , displayed on the user terminal  40 , user gets in the community, and then carries out a specified operation from the user terminal  40 , thereby, a search screen including at least search string input area and search execution instruction button, for example, as shown in  FIG. 21 , is provided from the input and output portion  7 . When search request including search string input into the search string input area of this search screen is sent to the input and output portion  7  of the server device  1 , this search request is transferred via the information search and presenting portion  4  to the community information management portion  2 . This search request includes the user ID of the user who has issued this search request. It is supposed that a natural sentence, for example, “Is there any example of patent publication?” is input as search string. 
   First, the information presenting portion  12  of the community information management portion  2  searches for messages and documents similar to search string among messages accumulated in the message accumulation portion  9  and documents accumulated in the document accumulation portion  10 , and generates a message set M 1  and a document set G 1  (steps S 201  and S 202 ). By the way, with respect to the method to search for messages and documents similar to search string, the art of “document search device” disclosed in the Japanese Patent Application KOKAI Publication No. 6-231178 mentioned previously may be employed. In search herein, for example, in reference to the management data of shared information as shown in  FIG. 18 , only shared information of the community that the user currently selects is searched. 
   The messages and documents listed respectively in the message set M 1  and the document set G 1 , as shown in  FIG. 16  and  FIG. 17 , include community ID of the community to which they belong in header information. The community information accumulated in the community information accumulation portion  8 , as shown in  FIG. 19 , includes user ID of user as member of the community, per community. Therefore, the information presenting portion  12  receives the community information from the Inter-community information management portion  3 , and checks whether the user ID of search request is listed as a member of the community in the community information. If it is listed therein, it is judged the user who has carried out search request is a member of the community, while, if it is not listed there, it is judged that the user is not a member of the community. 
   When the user who has carried out search request is not a member of the community, in principle, only documents can be presented to the user. Therefore, the processing is carried out only on the document set D 1 . First, the shared information management portion  2 , in reference to the management data shown in  FIG. 18 , removes documents whose publication is not permitted to outside of the community from the document set G 1  (step S 204 ). To this result, when there is document with different revision number in same document identification information, a document set G 2  comprising only document of the latest revision number is created (step S 205 ). Search result list L becomes a set G 2  (step S 206 ). 
   When the user who has carried out search request is a member of the community, in principle, both documents and messages can be presented to the user. Accordingly, among the message set M 1  generated at the step S 201 , those which have reference relations in messages (message tree) are collected into one element, and made into a set M 2  (step S 207 ). Next, to the document set G 1  as the result of the step S 202 , with respect to documents with different revision numbers in same document identification information, only documents of the latest revision numbers are collected, and a document set G 2  is created (step S 208 ). Next, the information management portion  11 , in reference to the management data shown in  FIG. 18 , generates a message set M 3  wherein those related to the document set G 2  are removed from the message set M 1  as the result of the step S 201 , on the basis of relations between messages and documents (step S 209 ). The total of G 2  and M 3  is made as search result list L of shared information (step S 210 ). This search result list L is displayed on, for example, the search result display screen as shown in  FIG. 22 . 
   The flow chart in  FIG. 29  shows the case when user selects a certain community, and in status getting in the community, searches for shared information, and as a result, search processing in the shared information of the community. On the other hand, when a user searches for shared information before selecting a community, the search objective becomes the whole shared information of all communities. 
   After a desired search string is input into the search string input area  621  of the search screen  620  in  FIG. 21 , displayed on the user terminal  40 , the search button  624  is pressed, thereby, search request including at least this search string is sent to the input and output portion  7  of the server device  1 . This research string is sent via the information search and presenting portion  4  to the community information control portion  2 . This search request includes the user ID of the user who has issued the search request. The processes thereafter are same as those in  FIG. 29 , but (since the processes in  FIG. 29  are for one community), in this case, search processes shown in  FIG. 29  are executed to the shared information of the community, per each community. By the way, in the step S 203 , since the user who has carried out the search request does not select the current community, in the step S 203 , the research request is treated as search request outside of the community, and the processes in steps S 204  through S 206  are carried out. That is, in each community, only public documents that may be made public to others than the members of the community are presented. In the step S 206 , the Inter-community information management portion  3  combines all the set G 1  per community (for example, obtains a logic sum thereof), and in each community, creates a collection of documents that may be made public to outside, and makes it as the search result list L, and sends back the result via the information search and presenting portion  4  to the user. Through these processes, it is possible to display, for example, the document list  653  in the search result display screen  640  in  FIG. 22 . 
   (7) Search of Shared Information Similar among Different Communities 
   The community information management portion  2  searches for shared information similar among different communities, by use of shared information (messages and documents) per community accumulated in the message accumulation portion  9  and the document accumulation portion  10 . This search may be carried out, for example, periodically, or at instruction from manager of the server device  1 . 
   With regard to the method to obtain similarity among shared information, in the same manner as mentioned previously, for example, the art of “document search device” disclosed in Japanese Patent Application KOKAI Publication No. 6-231178 may be employed. That is, when to search for shared information similar to shared information (messages and documents) registered in a certain community from other communities, first, morpheme analysis, construction analysis, and semantic analysis of shared information (messages and documents) as search key are carried out, and meaningful related words from words extracted as the result are combined by use of logic operators, and thereby new search string is created. From all the shared information of other all communities, shared information wherein the number of character strings to match this created search string is over a specified value may be extracted. 
   Each of shared information similar to each other existing in different communities is added header information as shown in  FIG. 16  and  FIG. 17 . In reference to this header information, search results are analyzed, thereby it is possible to make a notice as shown below to user. Herein, to make explanations simple, one of plural communities is called community A, and another community different from this community A is called community B. 
   Since it is possible to detect plural different communities where there are (preferably a plurality of) shared information similar to each other, the existence of other communities where similar shared information is registered to each member (at least manager of each community) of respective communities. 
   For example, when it is detected that document similar to shared information of the community A is registered in the community B, especially, when plural shared information pieces are similar to each other, it is considered that these two communities are similar communities where similar discussions are made, the notice that the community A and the community B are similar to each other is made to respective members of the communities A and B (at least manager of the community A). The notice of the existence of document (registered in the community B) similar to the shared information registered in the community A is sent to respective members of communities A and B (at least manager of the community A). In turn, the notice of the existence of document (registered in the community A) similar to the shared information registered in the community B is sent to respective members of the community B (at least manager of the community B). 
   When it is detected that shared information similar to shared information (one piece or plural pieces) that a user “a” as a member of the community A has registered to the community A is registered in the community B, the existence of the community B is notified to the user “a”. 
   When it is detected that shared information similar to shared information (one piece or plural pieces) that a user “a” as a member of the community A has registered to the community A is registered in the community B, the existence of the user “a” is notified to at least the manager of the community A. 
   For conducting such notices as mentioned above to user, a specified notice screen may be provided from the input and output portion  7  to each user terminal  40 . 
   Besides the shared information (messages and documents) per community accumulated in the message accumulation portion  9  and the document accumulation portion  10 , manager log information explained in  FIG. 26  may be also used. 
   (8) Presenting Comments to Users out of Community, and Making Them Participating in Community Temporarily 
   In a certain community, in principle, messages are not presented but only documents are presented in response to search request from users who are not members of the community (who have not yet participated in discussions in the community). However, this principle is observed strictly, there is a possibility that discussions in the community may be staggered. Accordingly, when a community manager permits, in response to search request from a specified user who is not a member of the community, in presenting documents of the community, at least, all or part of message trees corresponded to the presented documents are also presented at the same time. 
   That is, for example, the display screen shown in  FIG. 24  that is provided only to members of the community A may be provided also to user b who is not a member of the community A. By the way, in this case, on the display area  685  of the display screen in  FIG. 24 , only the contents of messages permitted by community manager are displayed. When a user b who has browsed such a display screen carries out a specified operation, the message registration screen is displayed. The message registration screen mainly comprises message text input area, and cannot create editing data or document. A message that is input to this message registration screen is posted to the community A as a reply to, for example, the message displayed in the display area  685  of the display screen in  FIG. 24 . This posted message may be presented to all the members of the community A, therefore, some members may register reply messages in response to the message. It is preferable that this reply message is presented unconditionally to this user b, at request from the user b. 
   [Second Embodiment] 
     FIG. 30  is a functional structure of a server device  1  according to a second embodiment of the present invention, about which, only a portion different from  FIG. 2  is explained hereinafter. That is, in the structure shown in  FIG. 30 , a user contribution degree calculation portion  15  is further added for calculating user&#39;s contribution degree in document creation. 
     FIG. 31  is an example of user information accumulated in the user information accumulation portion  5 , and is almost same as  FIG. 20 , but only portions different from  FIG. 20  are explained. That is, in  FIG. 31 , the user information consists of user ID  761 , name of user and belonging, mail address, log file name to accumulate personal system use history, and further a contribution degree record table  764 . 
   The contribution degree record table  764  describes how much contribution the user has been made to the community to which the user belongs. By the way, in  FIG. 31 , the values of contribution degree are regulated so that the total of contribution degree of all the users of each community to the community should become “1”. 
     FIG. 32  is a flow chart for explaining processing actions to calculate contribution degree of a user to a certain document to be identified by a certain document identification information piece in the user contribution degree calculation portion  15 , and in reference to this flow chart, explanations are made hereinafter. 
   Documents are updated as time goes on, however, in the processing in  FIG. 32 , contribution degree to documents are given to the user who is contributing to the document that is the latest document revision information, and the user who is the creator of the message referred to at the creation of the document that is the latest revision information. 
   First, the contribution degree to the user of the document of the revision number before the latest is obtained as below. When the latest version is set with revision number R, first, a set of creators who have gained contribution degrees is created, to each document of revision number i (0&lt;I&lt;R−1), and the contribution degrees are totaled per each creator (steps S 701  to S 703 ). The result of regulating the contribution degree by the number of updates before the latest (namely, “R−1”(step S 704 ) is set as the contribution degree K 1  to the updated documents before the latest (step S 705 ). 
   Next, the contribution degree to the creator of the message referred to at creation of the document of the latest revision number is calculated. First, a set J of messages referred to at creation of the latest document is obtained, and the degree of references per message is calculated. This may be calculated, for example, by regulating the number of lines referred to by the number of lines of document, and the like (steps S 706  and S 707 ). 
   This result per message is totaled per user as creator, and the reference degree of message per creator of the number Z (the number of users who participated in creation) is totaled (step S 708 ). This value is regulated by the number of creators Z, and further the obtained value is multiplied by weight w (0≦w≦1), thereby contribution degree per user is obtained (step S 709 ). 
   Finally, contribution degree (1−W)/Z is given to the user who has actually created the document (step S 710 ), which is made as contribution degree K 2  to the latest document creation obtained per user (step S 711 ). 
   By the way, the weight w used in the step S 709  and the step S 710  is a parameter to designate how much contribution degree should be distributed to labor of the user who has actually created the latest document. 
   Finally, the contribution degree K 1  up to the document of the revision number before the latest revision number, and the contribution degree K 2  at creation of the document of the latest revision number are totaled to obtain the contribution degree K 3  per user to documents. 
   When a document is newly created, since there is no document of former revision number, K 2  becomes the result (step S 715 ). Otherwise, K 1  and K 2  are totaled by use of weight w 2  (0≦w 2 ≦1), and thereby the result K 3  is obtained (steps S 713  and S 714 ). 
   By the way, the weight w 2  used herein is a parameter for designating how much the labor of user participating in creation of the document of old revision number is evaluated as contribution degree. 
     FIG. 33  is a flow chart for explaining processing actions for obtaining contribution degree of a user to a community the user contribution degree calculation portion  15 . First, by the processing actions shown in  FIG. 32 , user&#39;s contribution degree to all the documents in a certain community is obtained, and a set H of users who have contributed more or less to documents in the community is generated (step S 801 ). Then, contribution degree to documents as elements of the document set B in the community is totaled per user (step S 802 ), and finally, the contribution degree per user as element of the set H is regulated by the number of elements of the set B (the number of documents) (step S 803 ). 
   Through the processing, the user contribution degree calculation portion  15  can obtain contribution degree of user to community. The contribution degree of user to community may also be used to enhance the management authority of users having high contribution degrees to community (for example, authority to permit new users to participate in community, authority to permit documents in community to be made public to outside, etc.). For example, authority for updating the management data of shared information shown in  FIG. 18 , and the community information shown in  FIG. 19  may be given. 
   (Effects) 
   As explained heretofore, according to the first embodiment of the present invention, it is possible to refer to messages exchanged in process of document creation in efficient manners, thereby it makes easier for new users in community to grasp documents shared in the community and the transitions and backgrounds of document creation, as a result, sharing information in each community will be promoted. 
   By setting whether or not to make documents and messages public to outside of community, for example, it is possible to sort out documents that should not be made public to other communities, and document that have been made public, accordingly, in each community, it is possible to carry out confidential discussions without leaking them to other communities, as a consequence, sharing knowledge (documents) among communities will be facilitated. 
   By searching for and presenting not merely messages and documents similar to search string from all the communities, but also communities where fields similar to search request are discussed, it is possible for users to find out and participate in communities in which they are interested. 
   Also by searching for and presenting community preferable as message posting destination, it is possible to users to have discussions in community in which they are interested, which will help community to invite users&#39; participation. 
   In search for communities, the more the number of documents made public a community has, the more frequently such a community is presented among the research results, accordingly, such a community having more documents created and made public will be likely to attain more new users. For communities, frequent participation of new users will help activate discussions, therefore, creating many document that may be made public to members of other communities will lead to profits of the whole communities, which in turn will motivate creation of documents. 
   Further, by introducing communities where discussions are made on similar topics to each other, it is possible to integrate places for discussions by users who have same interest, thereby, for users, it is possible to select their communities suitably, while, for communities, it is possible to prevent members participating in discussions from dispersing. 
   Further, it is possible to inform members of community of existence of users who are interested in similar topics but do not know the existence of community or cannot take part in community. Thereby, it is possible to easily take in users who are interested in community, which in turn will activate discussions in community. 
   Still further, on the basis of search result, by informing members of a specific community of request for document creation from a user out of the specific community, creation of public documents in the community is motivated, and sharing information is facilitated. 
   According to the second embodiment of the present invention, by calculating and managing the contribution degree of users who have created documents to community, it is possible to fairly evaluate members who have contributed in creating documents that can be shared from messages as flow information. Thereby, creation of shared documents by each member will be motivated more, and sharing information will be promoted. 
   By the way, the approaches described in the first and second embodiments may be contained in and distributed in form of recording media such as DVD, CD-ROM, floppy disk, individual memory, optical disk and the like, as a program to be executed by a computer. 
   The approaches of the present invention described in the embodiments of the present invention may be contained in and distributed in form of recording media such as magnetic disks (floppy disk, hard disk, and the like), optical disks (CD-ROM, DVD, etc.), semiconductor memory, and the like, as a program to be executed by a computer. 
   Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.