Abstract:
A workflow management system wherein a workflow model is dynamically constituted when a workflow is executed, its method, and its computer-executable program are disclosed. The workflow management system includes
       a receiving unit for receiving access from an external terminal based on a protocol that is capable accessing a file system;   a providing unit for providing a folder list to the external terminal, wherein the folder list is acquired by converting a task layer of the workflow managed by the workflow management system into a folder layer of the file system; and   an appending unit for appending a document as relevant information to a task of the workflow corresponding to a predetermined folder layer when the document is uploaded by the external terminal.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a workflow management system wherein a workflow model is dynamically constituted when a workflow is executed. 
         [0003]    2. Description of the Related Art 
         [0004]    According to a conventional workflow management system it is necessary to define a workflow model before executing a workflow. However, in the cases of, e.g., research, development and some of service businesses, complete prior information is not available, and for this reason it is difficult to define a precedent workflow model. Then, a method called constructive workflow has been disclosed by, for example, JPA 2005-47792 (Patent Reference 1), and JPA 2005-154261, wherein a model is dynamically structured while executing the workflow. 
         [0005]    According to the constructive workflow method, a workflow is dynamically defined by basically assembling workflow components (typical partial workflows) that are beforehand defined. 
         [0006]    Further, given that the constructive workflow deals with an atypical business, it is important that a user be provided with various kinds of information relevant to tasks that constitute the workflow. In this connection, various kinds of documents relevant to the tasks (relevant information) can be appended to the tasks, and the user can be timely provided with such relevant information. 
         [0007]    Further, the workflow management system can be operated by a Web browser of a client PC (Personal Computer) connected through a network; accordingly, appending a document and perusal of an attached document can be performed from the Web browser. 
         [0008]    [Patent Reference 2] JPA 2005-285101 
       DISCLOSURE OF THE INVENTION 
     Objective of the Invention 
       [0009]    Although the conventional workflow management system handling the constructive workflow offers functions of appending a document to the task and perusing a document of the task, the functions are available to a client PC connected to the workflow management system through the network. That is, the function of appending a document to the task is not readily available to a terminal in a mobile environment, where a Client PC cannot be used. 
         [0010]    For example, if a person uses a digital camera and takes a photograph of the minutes of a meeting about a task that is an object of the workflow management system, which meeting is held outside of his/her office, he/she cannot append the photograph to the task until he/she returns to the office. That is, appending the latest information is delayed. This problem is common to the cases such as when a memo (text file) is drawn up with a PDA (Personal Digital Assistant) or a cellular phone, not limited to a photograph taken by a digital camera. 
         [0011]    In addition, although there are PDAs and cellular phone terminals that are capable of downloading and uploading a file through a network, uploading can be only to a specific folder of a server. That is, they are not capable of specifying a task layer of the workflow, nor capable of generating a new task and appending the file to the new task. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention is made to solve the problems described above, and provides a workflow management system that enables a mobile terminal to append a document to a desired task in addition to making reference to a task layer of a workflow and a document appended to the task. Here, the mobile terminal is required to include a protocol capable of accessing file systems, such as FTP (File Transfer Protocol), but is not required to include full-scale software, such as a Web browser. 
         [0013]    The workflow management system according to embodiments of the present invention substantially obviates one or more of the problems caused by the limitations and disadvantages of the related art. 
         [0014]    Features of embodiments of the present invention are set forth in the description that follows, and in part will become apparent from the description and the accompanying drawings, or may be learned by practice of the invention according to the teachings provided in the description. Problem solutions provided by an embodiment of the present invention may be realized and attained by a workflow management system particularly pointed out in the specification in such full, clear, concise, and exact terms as to enable a person having ordinary skill in the art to practice the invention. 
         [0015]    To achieve these solutions and in accordance with an aspect of the invention, as embodied and broadly described herein, an embodiment of the invention provides a workflow management system, wherein a workflow model is dynamically constituted when a workflow is executed, as follows. 
       MEANS FOR SOLVING A PROBLEM 
       [0016]    The workflow management system according to an aspect of the embodiment of the present invention includes a receiving unit for receiving access from an external terminal based on a protocol that is capable of accessing a file system; 
         [0017]    a providing unit for providing the external terminal with a folder layer of a file system that is obtained by converting a task layer of the workflow that is managed by the workflow management system; and 
         [0018]    an appending unit for appending a document as relevant information to a task of the workflow corresponding to a predetermined folder layer when the document is uploaded by the external terminal. 
         [0019]    According to another aspect of the embodiment, the workflow management system further includes a new task generating unit for generating a new task in a task layer of the workflow based on a request for generating a new folder from the external terminal. 
         [0020]    According to another aspect of the embodiment, when a document is uploaded for appending to a folder specified in the folder layer, the appending unit appends the document as relevant information to a task of the workflow corresponding to the folder specified. 
         [0021]    According to another aspect of the embodiment, when a document is uploaded for appending with no folder of the folder layer being specified, the appending unit appends the document as relevant information to a task of the workflow based on one of updating time and a keyword of the document. 
         [0022]    According to another aspect of the embodiment, when two or more documents are uploaded in a package for appending, the documents are divided into groups based on nearness (proximity) of updating time, and a task is specified for each of the groups. 
         [0023]    The embodiment of the present invention provides a workflow control method. 
         [0024]    The embodiment of the present invention provides a workflow control program. 
       EFFECTIVENESS OF INVENTION 
       [0025]    According to the workflow management system of the present invention as embodied herein, a mobile terminal is enabled to append a document to a desired task, in addition to its capability of referring to a task layer of a workflow and an appended document of a task; here, the mobile terminal is required to include a protocol that can access file systems, such as FTP, but is not required to include full-scale software, such as a Web browser. In this way, operability in the mobile environment is remarkably enhanced. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]      FIG. 1  is a block diagram of an example of a workflow management system according to an embodiment of the present invention; 
           [0027]      FIG. 2  is a sequence diagram showing an example of a process of a Client PC referring to a task list, and a process of the Client PC acquiring an appended document; 
           [0028]      FIG. 3  is a screen display showing an example of a task list as displayed by the Client PC; 
           [0029]      FIG. 4  is a sequence diagram showing an example of a process of a mobile terminal referring to a folder list (task list), and a process of the mobile terminal appending a document; 
           [0030]      FIG. 5  is a schematic drawing showing an example of corresponding relationships between a task layer and a folder layer; 
           [0031]      FIG. 6  is a screen display showing an example of the folder list (task list) displayed at a mobile terminal; 
           [0032]      FIG. 7  is a flowchart (No. 1) of an example of a process of converting a task layer to a folder layer; 
           [0033]      FIG. 8  is a flowchart (No. 2) of an example of a process of converting the task layer to the folder layer; 
           [0034]      FIG. 9  is a flowchart (No. 3) of an example of a process of converting the task layer to the folder layer; 
           [0035]      FIG. 10  is a flowchart of an example of a process of appending a document; 
           [0036]      FIG. 11  is a sequence diagram showing an example of a process of generating a new folder (task); 
           [0037]      FIG. 12  is a flowchart of an example of a process of generating a new folder (task); 
           [0038]      FIG. 13  is a sequence diagram of an example of a process of appending documents when the documents are uploaded in a package; and 
           [0039]      FIG. 14  is a flowchart of an example of a process of appending documents when the documents are uploaded in a package. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0040]    In the following, embodiments of the present invention are described with reference to the accompanying drawings. 
         [0041]    &lt;System Configuration&gt; 
         [0042]      FIG. 1  is a block diagram of an example of a workflow management system  1  according to an embodiment of the present invention. 
         [0043]    The workflow management system  1  includes a Client PC  2  and a mobile terminal  3  such as a PDA or a cellular phone that can be connected to the workflow management system  1  through a network. The client PC  2  includes a browser (Web browser)  21 . The mobile terminal  3  includes one of an FTP client  31  for accessing a file system by FTP, a WebDAV client  32  for accessing the file system by WebDAV (Web enabled Distributed Authoring and Versioning), and an smb client  33  for accessing the file system by smb (server message block). 
         [0044]    The workflow management system  1  includes 
         [0045]    a GUI control unit  11  for providing a GUI (Graphical User Interface) for access by the browser  21  of the client PC  2  that is operated by a user of the workflow management system  1 , and 
         [0046]    a folder view control unit  12   
         [0047]    for providing a folder view (folder layer display) corresponding to a task layer of a workflow to be accessed by the FTP client  31 , and the like, of the mobile terminal  3  that is operated by a user of the workflow management system  1 , 
         [0048]    for appending a document (an image file, a text file, etc.) to the task corresponding to the folder, and 
         [0049]    for generating a new folder (a new task). 
         [0050]    The GUI control unit  11  includes a rendering engine  111  for drawing a display screen, and an I/O control unit  112  for exchanging information with the user. 
         [0051]    The folder view control unit  12  includes 
         [0052]    a task layer converter  121  for converting a task layer of the workflow into a folder layer, 
         [0053]    an information extraction and OCR unit  122  for analyzing a document file (extracting words, etc., of a text file, and extracting words, etc., of an image file after an OCR process) for extracting an identification of the task, where the document file is uploaded for appending by the mobile terminal  3 , 
         [0054]    a new object generating unit  123  for generating a new object (a new task and a new folder) according to directions of the mobile terminal  3 , and 
         [0055]    an I/O control unit  124  for controlling input and output of the functional units of the workflow management system  1 . 
         [0056]    Further, the workflow management system  1  includes a workflow engine  13  for dynamically generating and executing a workflow model by reuse of an existing task model and/or a task instance, and a database  14  for holding information required for processes. 
         [0057]    The database  14  includes a user DB  141  for storing information on a user and a user group to which the user belongs; a task model DB  142  for storing a task model beforehand abstracted by a manager, and the like; a task instance DB  143  for storing a task instance; a relevant information DB  144  for storing relevant information that may be referred to when executing a workflow; and a document DB  145  for storing a document file of the relevant information. The information stored in the relevant information DB  144  is linked (associated) with contents of the task model DB  142  and the task instance DB  143 . 
         [0058]    The workflow engine  13  includes a search engine  131  for searching the database  14 , a task control unit  132  for controlling tasks that constitute the workflow, and a relevant information management unit  137  for managing the relevant information DB  144  and the document DB  145 . 
         [0059]    The task control unit  132  includes a task generating unit  133  for generating a task, a task execution unit  134  for executing the generated task, an estimating engine  135  for estimating a user&#39;s present task and for searching the database  14  for related information, and a task tree holding unit  136  for managing a task layer in a tree format. 
         [0060]    When the new object generating unit  123  generates a new object, the task generating unit  133  generates the new task. 
         [0061]    Basic operations of workflow control include that the user operates the workflow engine  13  through the I/O control unit  112  of the GUI control unit  11  such that a workflow may be generated and executed, a workflow model may be generated, relevant information and a document may be stored, and the relevant information and the document may be linked with the workflow instance and the workflow model. 
         [0062]    When generating the workflow, the search engine  131  of the workflow engine  13  searches the database  14  for various information items. 
         [0063]    The task control unit  132  of the workflow engine  13  uses the task model DB  142  and the task instance DB  143 , and controls a task based on user directions, and the like. The task generating unit  133  of the task control unit  132  generates the task, and provides linkage of the information, etc., based on the information stored in the database  14  according to the user directions. The task execution unit  134  uses the information stored in the task instance DB  143  according to user directions, and updates actual task information. Here, updating the task information is a task execution if viewed from the workflow management system. 
         [0064]    &lt;Operation&gt; 
         [0065]      FIG. 2  is a sequence diagram of an example of a process of viewing a task list and acquiring an appended document by the client PC  2 . 
         [0066]    In  FIG. 2 , a login is requested from the browser  21  of the client PC  2  to the GUI control unit  11  of the workflow management system  1  (step S 101 ), then, the GUI control unit  11  requests a login authentication by the user DB  141  (step S 102 ). If the login request is authenticated (step S 103 ), the GUI control unit  11  returns a “login success” to the browser  21  of the client PC  2  (step S 104 ). 
         [0067]    Subsequently, the browser  21  of the client PC  2  requests a task list  201  from the GUI control unit  11  of the workflow management system  1  (step S 105 ); then, the GUI control unit  11  searches the task instance DB  143  for a task list of the login user (step S 106 ). If the task list  201  is acquired (step S 107 ), the GUI control unit  11  provides the acquired task list  201  to the browser  21  of the client PC  2  (step S 108 ). 
         [0068]      FIG. 3  shows an example of a screen display of the task list  201  displayed at the client PC  2 , wherein the task list  201  hierarchically presents tasks related to the login user. If one of the tasks is selected (a selected task  202 ), an appended document list  203  displays appended documents related to the selected task  202 . In the appended document list  203 , document names, e.g., “PaperDraftFinal.doc”, are presented under an appended document folder (appended information category), namely, “Task Attachments”. 
         [0069]    Returning to  FIG. 2 , the browser  21  of the client PC  2  requests an appended document from the GUI control unit  11  of the workflow management system  1  (step S 109 ); the GUI control unit  11  searches the relevant information DB  144  for an ID of the requested document (step S 110 ), and acquires a Document ID (step S 111 ). 
         [0070]    Then, the GUI control unit  11  acquires the requested document from the document DB  145  based on the Document ID (steps S 112  and S 113 ), and provides the requested appended document to the browser  21  of the client PC  2  (step S 114 ). 
         [0071]      FIG. 4  is a sequence diagram showing an exemplary case wherein the mobile terminal  3  displays the folder list (task list), and appends a document. Here, according to the example, an access is made by the FTP client  31  of the mobile terminal  3 ; however, the same operation is applicable to the case wherein one of the WebDAV client  32  and the smb client  33  makes the access. 
         [0072]    In  FIG. 4 , the FTP client  31  of the mobile terminal  3  sends a login request to the folder view control unit  12  of the workflow management system  1  (step S 121 ), then the folder view control unit  12  requests login authentication of the user by the DB  141  (step S 122 ), and if the login is authenticated (step S 123 ), the folder view control unit  12  provides a “login success” to the FTP client  31  of the mobile terminal  3  (step S 124 ). 
         [0073]    Then, the FTP client  31  of the mobile terminal  3  requests the folder list (although the folder list is formally requested, the task list is essentially requested) from the folder view control unit  12  of the workflow management system  1  (step S 125 ). Then, the folder view control unit  12  of the workflow management system  1  searches the task instance DB  143  for the task list related to the login user (step S 126 ), and acquires the task list (step S 127 ). 
         [0074]    Subsequently, the folder view control unit  12  searches the relevant information DB  144  for relevant information (step S 128 ), and acquires the search results (relevant information and a task layer) (step S 129 ). 
         [0075]    Subsequently, the folder view control unit  12  converts the acquired task layer into a folder layer (step S 130 ), and provides the folder list (obtained by converting the task list) to the FTP client  31  of the mobile terminal  3  (step S 131 ). That is, the task layer of the workflow management system  1  is converted into the folder layer so that the folder list may be provided for viewing at the FTP client  31  of the mobile terminal  3 . The relevant information appended to the task is converted into a file so that it may be visible in the folder. 
         [0076]      FIG. 5  shows an example of corresponding relationships between the task layer and the folder layer, wherein on the left-hand side at (a), the task layer before conversion is shown, and on the right-hand side at (b), the folder layer after conversion is shown. 
         [0077]    As for the task layer at (a), a task T 1  includes subtasks T 2  through T 4  (connected by bold lines). Further, the subtask T 3  includes subtasks T 5  and T 6  (connected by bold lines). The task T 1  includes an appended information category Fo 1  that accommodates an attached file (appended document) Fi 1 . The subtask T 4  includes an appended information category Fo 2  that accommodates an attached file Fi 2 . The subtask T 5  includes an appended information category Fo 3  that accommodates attached files Fi 3  and Fi 4 . 
         [0078]    As for the folder layer at (b), task corresponding folders (folders that are converted from tasks) TF 1  through TF 6  are shown, which correspond to the tasks/subtasks T 1  through T 6 , respectively, shown at (a), wherein the hierarchical structure is maintained. The appended information category Fo 1  associated with the task T 1  at (a) is converted to a category corresponding folder CF 1  (folder that is converted from appended information category) at (b), wherein the CF 1  directly belongs to the task corresponding folder TF 1 . In this way, although there are cases wherein a class category (appended information category) is added to a task as appending information in order to arrange the information appended to a task, since it is natural to show such a classification configuration as a folder when accessing by a protocol such as FTP, it is converted into the category corresponding folder. 
         [0079]    The attached file Fi 1  accommodated in the appended information category Fo 1  at (a) is accommodated in the category corresponding folder CF 1  at (b). The appended information category Fo 2  under the subtask T 4  at (a) corresponds to a category corresponding folder CF 2  directly under the task corresponding folder TF 4  at (b). The attached file Fi 2  accommodated in the appended information category Fo 2  at (a) is accommodated in the category corresponding folder CF 2  at (b). The appended information category Fo 3  under the subtask T 5  at (a) corresponds to a category corresponding folder CF 3  directly under the task corresponding folder TF 5  at (b). The attached files Fi 3  and Fi 4  accommodated in the appended information category Fo 3  at (a) are accommodated in the category corresponding folder CF 3  at (b). 
         [0080]      FIG. 6  shows an example of the folder list (task list) displayed at the mobile terminal  3 , and corresponds to the task layer shown in  FIG. 3 . Here, the specific display format may vary with applications of the mobile terminal  3 . 
         [0081]    With reference to  FIG. 6 , a folder layer column  301  gives a hierarchical display of the folders (the task corresponding folder or the category corresponding folder, as applicable) obtained by converting the tasks and the appended information categories. In order to clarify the corresponding relationship between a task and an appended information category, “Task” is prefixed to a task corresponding folder name, and “Cat” is prefixed to a category corresponding folder name. 
         [0082]    An appended file column  303  shows contents (a lower category corresponding folder and appended files) of a selected folder  302  (“CatReferences” folder in this example) that is selected in the folder layer column  301 . 
         [0083]    With reference to  FIG. 4 , again, the FTP client  31  of the mobile terminal  3  requests the folder view control unit  12  of the workflow management system  1  to append a document that is attached to the request into a folder (task) that is specified by the request (step S 132 ). The request from the FTP client  31  of the mobile terminal  3  to append the document is communicated using a standard file download/upload process. Then, the folder view control unit  12  stores the document to be appended in the document DB  145  (step S 133 ), and acquires a document ID for identifying the stored document (step S 134 ). 
         [0084]    Then, the folder view control unit  12  generates task document relevant information and stores the information in the relevant information DB  144  (step S 135 ). In this way, the document is appended to the specified task. 
         [0085]    Here, correspondence of the task layer to the folder layer is summarized:
       Viewing the task layer: Viewing the folder layer   Viewing information appended to the task: Viewing the file in the folder, and viewing the sub folder   Appending information to the task: Uploading the file (put)   Updating information on appended documents: Overwriting upload   Generating a new subtask: Generating a folder   Bibliographic information of the task: an information file having a specific file name (TaskInfo.Txt)       
 
         [0092]      FIGS. 7 through 9  are flowcharts showing an example of a process of converting (step S 130 ) from the task layer to the folder layer as shown in  FIG. 4 . 
         [0093]    First, a process of “conversion of a task into a folder” is described with reference to  FIG. 7 . 
         [0094]    The process of “conversion of a task into a folder” is performed with a target task (a task included in a task list) “task” serving as a parameter (step S 141 ). Then, an empty folder is generated serving as a folder “f” (step S 142 ). 
         [0095]    Subsequently, a process of “adding the task to the folder” (step S 143 ) is performed with the folder “f” and the “task” serving as parameters, and the process is ended (step S 144 ). 
         [0096]      FIG. 8  is a flowchart showing an example of processes performed at the step S 143 , “adding the task to the folder”. 
         [0097]    With reference to  FIG. 8 , when “adding the task to the folder” is started (step S 151 ) with the folder “f” and task “t” serving as the parameters, a task folder name is first generated (step S 152 ). That is, a character string “Task” is prefixed to a task name (t. task name (task name property of an object t)) to make a task folder name “f 1 name”. 
         [0098]    Subsequently, a sub folder “f 1 ” is generated under the folder “f”; and then, the task folder name “f 1 name” is assigned as the name of the folder “f 1 ” (f 1 .name) (step S 153 ). 
         [0099]    Subsequently, bibliographic information of the task “t” is written to a text file “TaskInfo.txt”, and the text file is stored in the sub folder “f 1 ” (step S 154 ). 
         [0100]    Subsequently, a list of relevant information of the task “t” is made into a list “al” (step S 155 ). 
         [0101]    Then, whether the list “al” is empty is determined (step S 156 ). 
         [0102]    If the list “al” is not empty (No at step S 156 ), the relevant information is taken out from the list “al”, and is made into an item “al” (step S 157 ). 
         [0103]    Subsequently, at step S 158 , the item “al” is added to the folder “f 1 ”. Then, the process returns to the step S 156  for determining whether the list “al” is empty. 
         [0104]    Otherwise, if the list “al” is empty (Yes at step S 156 ), a subtask list of the task “t” is made into a list “tl” (step S 159 ). 
         [0105]    Then, whether the list “tl” is empty is determined (step S 160 ). 
         [0106]    If the list “tl” is not empty (No at step S 160 ), a subtask is taken out from the list “tl”, and is made into a “task t 1 ” (step S 161 ). 
         [0107]    Subsequently, “adding a task to the folder” by the steps S 151  through S 163  is recursively carried out (step S 162 ) with the folder “f 1 ” and the task “t 1 ” serving as the parameters. Then, the process returns to the step S 160  for determining whether the list “tl” is empty. 
         [0108]    If the list “tl” is empty (Yes at step S 160 ), the process is ended (step S 163 ). 
         [0109]      FIG. 9  is a flowchart of an example of processes of the step S 158 , “adding relevant information to the folder”. 
         [0110]    When “adding relevant information to the folder” (S 171 ) is started with the folder “f” and an item “a” serving as parameters in  FIG. 9 , whether the item “a” is an appended file is first determined (step S 172 ). 
         [0111]    If the item “a” is an appended file (Yes at step S 172 ), the item “a” is added to the folder “f” (step S 173 ), and the process is ended (step S 180 ). 
         [0112]    Otherwise, if the item “a” is not an appended file (No at step S 172 ) (i.e., if it is an appended folder), a category folder name “f 1 name” is generated, wherein a character string “Cat” is prefixed to the task name (a.task name) (step S 174 ). 
         [0113]    Subsequently, a sub folder “f 1 ” is generated under the folder “f”; further, the category folder name “f 1 name” already generated is made into the name of the sub folder “f 1 ” (f 1 .name) (step S 175 ). 
         [0114]    Subsequently, the relevant information list in the item “a” is made into the list “al” (step S 176 ). 
         [0115]    Then, whether the list “al” is empty is determined (step S 177 ). 
         [0116]    If the list “al” is not empty (No at step S 177 ), the relevant information is taken out from the list “al”, and is made into the item “a 1 ” (step S 178 ). 
         [0117]    Subsequently, “adding the relevant information to the folder”, i.e., the steps S 171  through S 180 , is recursively carried out (step S 179 ) with the “folder “f 1 ”” and the item “a 1 ” serving as the parameters. Then, the process returns to the step S 177  for determining whether the list “al” is empty. 
         [0118]    If the list “al” is empty (Yes at step S 177 ), the process is ended (step S 180 ). 
         [0119]      FIG. 10  is a flowchart of an example of processes of the steps S 133  through S 135 , “appending a document” shown in  FIG. 4 . 
         [0120]    With reference to  FIG. 10 , when “uploading an attachment file” is started (step S 181 ) with a parent item (“parent”), an attachment file name (“name”), and contents (“contents”) serving as the parameters, whether the attachment file bearing the attachment file name is a new file is determined (step S 182 ). 
         [0121]    If the attachment file is a new file (Yes at step S 182 ), whether the attachment file name (“name”) is “TaskInfo.txt” is determined (step S 183 ). 
         [0122]    If the attachment file name (“name”) is “TaskInfo.txt” (Yes at step S 183 ), whether the parent item (“parent”) corresponds to a task is determined (step S 184 ). 
         [0123]    If the parent item does not correspond to a task (No at step S 184 ), the process moves to step S 194  for error handling, and the process is ended (step S 195 ). 
         [0124]    If the parent item corresponds to a task (Yes at step S 184 ), the task that corresponds to the parent item (“parent”) is made into the task (“task”) (step S 185 ). 
         [0125]    Subsequently, information about the task (“task”) is updated according to the contents (“contents”) (step S 186 ), and the process is ended (step S 195 ). 
         [0126]    If the attachment file name (“name”) is not “TaskInfo.txt” (No at step S 183 ), the file having the attachment file name (“name”) is overwritten by the new file (step S 187 ), and the process is ended (step S 195 ). 
         [0127]    Otherwise, if the uploaded file to be appended is not a new file (No at step S 182 ), whether the attachment file name (“name”) is “TaskInfo.txt” is determined (step S 188 ). 
         [0128]    If the attachment file name (“name”) is “TaskInfo.txt” (Yes at step S 188 ), the process moves to step S 194  for error handling, and the process is ended (step S 195 ). 
         [0129]    If the attachment file name (“name”) is not “TaskInfo.txt” (No at step S 188 ), whether the parent item (“parent”) corresponds to the task is determined (step S 189 ). 
         [0130]    If the parent item does not correspond to the task (No at step S 189 ), an appending folder corresponding to the parent item (“parent”) is made into a folder “pfolder” (step S 190 ). 
         [0131]    Subsequently, a file having the attachment file name (“name”) is generated under the folder “pfolder” (step S 191 ), and the process is ended (step S 195 ). 
         [0132]    Otherwise, if the parent item corresponds to a task (Yes at step S 189 ), the task corresponding to the parent item (“parent”) is made into the task (“task”) (step S 192 ). 
         [0133]    Subsequently, a file having the attachment file name (“name”) is generated and is attached to the task (“task”) (step S 193 ), and the process is ended (step S 195 ). 
         [0134]      FIG. 11  is a sequence diagram showing an example of a new folder (“task”) generating process. 
         [0135]    With reference to  FIG. 11 , the FTP client  31  of the mobile terminal  3  sends a login request to the folder view control unit  12  of the workflow management system  1  (step S 201 ), and the folder view control unit  12  requests a login authentication from the user DB  141  (step S 202 ). If logging in is authenticated (step S 203 ), the folder view control unit  12  provides a “login success” to the FTP client  31  of the mobile terminal  3  (step S 204 ). 
         [0136]    Subsequently, the FTP client  31  of the mobile terminal  3  requests a folder list (which essentially is a task list while the folder list is formally requested) from the folder view control unit  12  of the workflow management system  1  (step S 205 ), and the folder view control unit  12  searches the task instance DB  143  for the task list concerning the login user (step S 206 ), and acquires the task list (step S 207 ). 
         [0137]    Subsequently, the folder view control unit  12  searches the relevant information DB  144  for relevant information (step S 208 ), and acquires a search result (task layer and relevant information) (step S 209 ). 
         [0138]    Subsequently, the folder view control unit  12  converts the task layer into the folder layer (step S 210 ), and provides the folder list (obtained by converting the task list) to the FTP client  31  of the mobile terminal  3  (step S 211 ). 
         [0139]    Then, the FTP client  31  of the mobile terminal  3  requests the folder view control unit  12  of the workflow management system  1  to generate a new folder (step S 212 ), and the folder view control unit  12  generates a new subtask in the task instance DB  143  (step S 213 ). If the user gives a prefix when requesting the generation of the folder, the subtask and a sub category can be generated. 
         [0140]    Subsequently, the folder view control unit  12  generates a new appending folder in the relevant information DB  144  (step S 214 ). 
         [0141]      FIG. 12  is a flowchart showing an example of processes of the new folder (“task”) generation (steps S 212  through S 214  of  FIG. 11 ). 
         [0142]    A process of generating a new folder is started with the parent item (“parent”) and the name (“name”) serving as the parameters (step S 221 ) as shown in  FIG. 12 . Then, whether the name (“name”) starts with “Cat” is first determined (step S 222 ). 
         [0143]    If it is determined that the name (“name”) starts with “Cat” (Yes at step S 222 ), a part of the name (“name”) excluding “Cat” is made into a “name catname” (step S 223 ). 
         [0144]    Next, whether the parent item (“parent”) corresponds to a task is determined (step S 224 ). 
         [0145]    If the parent item (“parent”) does not correspond to a task (No at step S 224 ), an appending folder corresponding to the parent item (“parent”) is made into a folder “pfolder” (step S 225 ). 
         [0146]    Subsequently, a “sub folder catname” is generated under the appending folder “pfolder” (step S 226 ), and the process is ended (step S 235 ). 
         [0147]    If the parent item (“parent”) corresponds to a task (Yes at step S 224 ), the task corresponding to the parent item (“parent”) is made into a task “ptask” (step S 227 ). 
         [0148]    Subsequently, the appending folder “catname” is generated under the task “ptask” (step S 228 ), and the process is ended (step S 235 ). 
         [0149]    If the name (“name”) does not start with “Cat” (No at step S 222 ), whether the name (“name”) starts with “Task” is determined (step S 229 ). 
         [0150]    If the name (“name”) does not start with “Task” (No at step S 229 ), an error process at step S 234  is carried out, and the process is ended at step S 235 . 
         [0151]    If the name (“name”) starts with “Task” (Yes at step S 229 ), a part of the name (“name”) excluding “Task” is made into a name “taskname” (step S 230 ). 
         [0152]    Next, whether the parent item (“parent”) corresponds to a task is determined (step S 231 ). 
         [0153]    If the parent item (“parent”) does not correspond to a task (No at step S 231 ), the error process is carried out at step S 234 , and the process is ended at step S 235 . 
         [0154]    If the parent item (“parent”) corresponds to a task (Yes at step S 231 ), the task corresponding to the parent item (“parent”) is made into the task “ptask” (step S 232 ). 
         [0155]    Then, a “subtask taskname” is generated under the task “ptask” (step S 233 ), and the process is ended at step S 235 . 
         [0156]      FIG. 13  is a sequence diagram of an example of a process of appending documents that are uploaded in a package. 
         [0157]    With reference to  FIG. 13 , the FTP client  31  of the mobile terminal  3  requests to login to the folder view control unit  12  of the workflow management system  1  (step S 241 ). Then, the folder view control unit  12  requests a login authentication by the user DB  141  (step S 242 ). If the login is authenticated (step S 243 ), the folder view control unit  12  provides a “login success” to the FTP client  31  of the mobile terminal  3  (step S 244 ). 
         [0158]    Then, files are uploaded in a package by the FTP client  31  of the mobile terminal  3  to the folder view control unit  12  of the workflow management system  1  (step S 245 ), and the folder view control unit  12  extracts file-updating times and keywords from the uploaded files (step S 246 ). If the uploaded files include a file containing an image taken with a digital camera, time of picture taking, GPS (Global Positioning System) location information, etc., can be acquired from an Exif (Exchangeable Image File Format). If the image is obtained by scanning an image of a document, a keyword is extracted by using an OCR technique. If the file is an ordinary text file, the updating time, the keyword, etc., can be directly acquired from the file. Then, the files are grouped (clustering) according to the nearness (proximity) of the time using the updating times acquired as described above. 
         [0159]    Subsequently, the folder view control unit  12  searches the task instance DB  143  for a task based on the time and the keyword that are extracted (step S 247 ), and acquires a task list (step S 248 ). That is, if there is a task that is or will be executed at the time, a keyword of which task is present in the task instance DB  143 , tasks containing the keyword are searched for. Here, information about grouping described above is utilized; that is, searching is carried out for each group; in this way, a minor time difference is disregarded. Since grouping is carried out based on the updating time, tasks can be searched for based on more information. Further, when keyword information is acquirable from the uploaded files, a ranking search of the task instance DB  143  is carried out with the keywords of all the files included in a group serving as search conditions, and a task of the highest position in the tree hierarchy is identified. 
         [0160]    Subsequently, the folder view control unit  12  stores the appended documents in the document DB  145  (step S 249 ), and acquires document IDs for identifying the stored documents (step S 250 ). 
         [0161]    Subsequently, the folder view control unit  12  generates task document relevant information and stores the same in the relevant information DB  144  (step S 251 ) in association with the already specified task. If no task corresponding to the group can be specified, and if there is a task that corresponds to another group, association is made with the parent task. 
         [0162]    In the above, the descriptions are made wherein two or more documents are uploaded in a package without specifying a folder in the folder layer; however, even if a single document is uploaded without specifying a folder in the folder layer, the document can be appended as relevant information by specifying a task based on one of the updating time and the keyword of the document. 
         [0163]      FIG. 14  is a flowchart showing an example of the process of uploading files in a package (steps S 245  through S 251 ) of  FIG. 13 . 
         [0164]    With reference to  FIG. 14 , “file package uploading” is started with files (“files”) serving as the parameter (step S 261 ). Then, updating time of each file is acquired (step S 262 ). 
         [0165]    Then, the files are divided into groups according to updating time (step S 263 ). That is, a cluster function “cluster (files)” is applied to the files (“files”), and a result is made into a list “c 1 ”. 
         [0166]    Then, a task is searched for in a range between two limits of the updating times, and a task list obtained as a search result is made into a list “tl” (step S 264 ). 
         [0167]    Subsequently, an item “th” is made empty, and an item “cnh” is made empty (step S 265 ). 
         [0168]    Then, it is determined whether the list “c 1 ” is empty (step S 266 ). 
         [0169]    If the list “c 1 ” is not empty (No at step S 266 ), a file group is taken out from the list “c 1 ” and is made into an item “c” (step S 267 ). 
         [0170]    Then, a task whose time corresponds to the item “c” in the list “tl” is made into the task “t” (step S 268 ). 
         [0171]    Subsequently, it is determined whether the task “t” is present (step S 269 ). 
         [0172]    If the task “t” is present (Yes at step S 269 ), the file of the item “c” is appended to the task “t”, and the task “t” is added to the item “th” (step S 270 ). Then, the process returns to step S 266  where it is determined whether the list “c 1 ” is empty. 
         [0173]    When the task “t” is not present (No at step S 269 ), the item “c” is added to the item “cnh” (step S 271 ), and the process returns to step S 266  where it is determined whether the list “c 1 ” is empty. 
         [0174]    If the list “c 1 ” is empty (Yes at step S 266 ), whether the item “cnh” is empty is determined (step S 272 ). 
         [0175]    If the item “cnh” is empty (Yes at step S 272 ), the process is ended (step S 277 ). 
         [0176]    If the item “cnh” is not empty (No at step S 272 ), whether the item “th” is empty is determined (step S 273 ). 
         [0177]    If the item “th” is not empty (No at step S 273 ), an immediate ancestor task that is common to the task of the item “th” is made into an item “p” (step S 274 ). 
         [0178]    If the item “th” is empty (Yes at step S 273 ), a root task is made into the item “p” (step S 275 ). 
         [0179]    Then, the file of the item “cnh” is appended to the item “p” (step S 276 ), and the process is ended (step S 277 ). 
         [0180]    &lt;Summary&gt; 
         [0181]    As described above, advantages of the embodiments of the present invention are as follows. 
         [0182]    (1) Since the task layer is mapped to the folder layer, a mobile terminal that has a protocol such as FTP, WebDAV, and smb for handling a layer file system is capable of accessing the workflow management system, and capable of handling the layer task and its appended information with an existing (conventional) client function. 
         [0183]    (2) Since an image provided by an image pick-up device, a file transmitted from a PDA, and the like, can be appended to a task that is determined based on updating time, they can be easily associated with a task that is carried out, or that is to be carried out at the corresponding time. 
         [0184]    (3) By placing two or more files into groups by comparing the updating time of a file with others, a task can be selected with great accuracy. 
         [0185]    Further, the present invention is not limited to these embodiments, but variations and modifications may be made without departing from the scope of the present invention. 
         [0186]    The present application is based on Japanese Priority Application No. 2007-062239 filed on Mar. 12, 2007 with the Japanese Patent Office, the entire contents of which are hereby incorporated by reference.