Patent Publication Number: US-2013232005-A1

Title: E-book advertisement system, e-book advertisement method, client device, advertisement-provision device, program, information-recording medium, and e-book update system

Description:
TECHNICAL FIELD 
     The present invention relates to an e-book advertisement system, an e-book advertisement method, a client device, an advertisement-provision device, a program, an information-recording medium, and an e-book update system. 
     BACKGROUND ART 
     There is a system for providing individual users with advertisements selected to meet preferences of the individual users. For example, in Patent Literature 1 below, there is disclosed a system in which advertisements are selected by using preference information based on the past browsing history information on a user, and contents including the selected advertisements are delivered by means of streaming to a terminal of the user. 
     CITATION LIST 
     Patent Literature 
     
         
         [Patent Literature 1] JP 2002-259433 A 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     However, the conventional technology described above cannot update advertisements in an e-book once passed over to a user, based on contents which the user has browsed and has paid attention to in the e-book. 
     The present invention has been made in view of the above-mentioned problem, and therefore has an object to provide an e-book advertisement system, an e-book advertisement method, a client device, an advertisement-provision device, a program, an information-recording medium, which are capable of updating advertisements in an e-book based on contents which a user has browsed and has paid attention to in the e-book. 
     Solution to Problem 
     In order to solve the above-mentioned problem, according to the present invention, there is provided an e-book advertisement system, including: e-book acquisition means for acquiring an e-book including a text page and an advertisement page; display means for displaying at least apart of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; advertisement data acquisition means for acquiring, based on a history of the page and the zoomed-in part displayed on the display means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and update means for updating the advertisement page based on the advertisement data acquired by the advertisement data acquisition means. 
     According to an aspect of the present invention, the update means updates an advertisement page which has not been displayed on the display means yet based on the advertisement data acquired by the advertisement data acquisition means. 
     According to an aspect of the present invention, the e-book advertisement system further includes calculation means for calculating, based on at least one of a period of display and a number of times of display of the page and the zoomed-in part displayed on the display means, an evaluation value for each of the advertisement subjects determined in advance for the page and the zoomed-in part, and the advertisement data acquisition means selects, based on the evaluation value calculated for the each of the advertisement subjects, an advertisement subject to be provided to the user, and acquires the advertisement data associated with the selected advertisement subject. 
     According to an aspect of the present invention, the calculation means calculates the evaluation value for the each of the advertisement subjects determined in advance for the page and the zoomed-in part with a weight to be multiplied by the period of display or the number of times of display of the zoomed-in part being larger than a weight to be multiplied by the period of display or the number of times of display of the page. 
     According to an aspect of the present invention, the display control means provides control so that the advertisement page updated based on the advertisement data is displayed on the display means for a period longer than a period determined for the advertisement data acquired by the advertisement data acquisition means. 
     According to the present invention, there is also provided an e-book advertisement method, including: acquiring an e-book including a text page and an advertisement page; displaying at least a part of a page included in the e-book on display means; switching, when a page switching operation is received from a user, a page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; acquiring, based on a history of the page and the zoomed-in part displayed on the display means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and updating the advertisement page based on the acquired advertisement data. 
     According to the present invention, there is further provided an e-book advertisement system, including: a client device; and an advertisement-provision device, in which: the client device includes: e-book acquisition means for acquiring an e-book including a text page and an advertisement page; display means for displaying at least a part of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; and transmission means for transmitting the history of the page and the zoomed-in part recorded by the recording means to the advertisement-provision device; the advertisement-provision device includes: advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part transmitted by the transmission means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and advertisement data transmission means for transmitting the advertisement data acquired by the advertisement data acquisition means to the client device; and the client device further includes update means for updating the advertisement page based on the advertisement data transmitted by the advertisement data transmission means. 
     According to an aspect of the present invention, the transmission means transmits, at a timing when the client device communicates to/from the advertisement-provision device, the history of the page and the zoomed-in part recorded by the recording means by the timing to the advertisement-provision device. 
     According to the present invention, there is further provided a client device, including: e-book acquisition means for acquiring an e-book including a text page and an advertisement page; display means for displaying at least a part of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part recorded by the recording means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and update means for updating the advertisement page based on the advertisement data acquired by the advertisement data acquisition means. 
     According to the present invention, there is further provided a program for controlling a computer to function as: e-book acquisition means for acquiring an e-book including a text page and an advertisement page; display means for displaying at least a part of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part recorded by the recording means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and update means for updating the advertisement page based on the advertisement data acquired by the advertisement data acquisition means. 
     According to the present invention, there is further provided an information-recording medium having recorded thereon a program for controlling a computer to function as: e-book acquisition means for acquiring an e-book including a text page and an advertisement page; display means for displaying at least a part of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part recorded by the recording means, advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and update means for updating the advertisement page based on the advertisement data acquired by the advertisement data acquisition means. 
     According to the present invention, there is further provided an advertisement-provision device for providing a client device with advertisement data of an e-book including a text page and an advertisement page, the client device including: e-book acquisition means for acquiring the e-book; display means for displaying at least a part of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; and transmission means for transmitting the history of the page and the zoomed-in part recorded by the recording means to the advertisement-provision device, the advertisement-provision device including: advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part transmitted by the transmission means, the advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and advertisement data transmission means for transmitting the advertisement data acquired by the advertisement data acquisition means to the client device. 
     According to the present invention, there is further provided a program for controlling a computer, which functions as an advertisement-provision device for providing a client device with advertisement data of an e-book including a text page and an advertisement page, the client device including: e-book acquisition means for acquiring the e-book; display means for displaying at least apart of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; and transmission means for transmitting the history of the page and the zoomed-in part recorded by the recording means to the advertisement-provision device, the program controlling the computer to function as: advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part transmitted by the transmission means, the advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and advertisement data transmission means for transmitting the advertisement data acquired by the advertisement data acquisition means to the client device. 
     According to the present invention, there is further provided an information-recording medium having recorded thereon a program for controlling a computer, which functions as an advertisement-provision device for providing a client device with advertisement data of an e-book including a text page and an advertisement page, the client device including: e-book acquisition means for acquiring the e-book; display means for displaying at least apart of a page included in the e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; recording means for recording a history of the page and the zoomed-in part displayed on the display means; and transmission means for transmitting the history of the page and the zoomed-in part recorded by the recording means to the advertisement-provision device, the program controlling the computer to function as: advertisement data acquisition means for acquiring, based on the history of the page and the zoomed-in part transmitted by the transmission means, the advertisement data associated with an advertisement subject selected from advertisement subjects determined in advance for the page and the zoomed-in part; and advertisement data transmission means for transmitting the advertisement data acquired by the advertisement data acquisition means to the client device. 
     According to the present invention, there is further provided an e-book update system, including: display means for displaying at least a part of a page included in an e-book; display control means for switching, when a page switching operation is received from a user, the page displayed on the display means, and zooming in and displaying, when a page zooming-in operation is received from the user, a specified part on the page displayed on the display means; data acquisition means for acquiring, based on a history of the page and the zoomed-in part displayed on the display means, data associated with classification information selected from classification information determined in advance for the page and the zoomed-in part; and update means for updating the page included in the e-book based on the data acquired by the data acquisition means. 
     ADVANTAGEOUS EFFECTS OF INVENTION 
     According to an aspect of the present invention, advertisements in an e-book may be updated based on contents which a user has browsed and has paid attention to in the e-book. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  A system configuration diagram of an e-book advertisement system according to an embodiment of the present invention. 
         FIG. 2  A sequence diagram illustrating an example of processing carried out in the e-book advertisement system. 
         FIG. 3  A diagram illustrating an example of an e-book. 
         FIG. 4A  A diagram illustrating an example of the e-book after advertisement pages are updated. 
         FIG. 4B  A diagram illustrating an example of the e-book after an advertisement page is updated. 
         FIG. 5  A functional block diagram illustrating an example of functions provided in a client device and an advertisement data delivery server. 
         FIG. 6  A diagram illustrating an example of browsing history data. 
         FIG. 7  A diagram illustrating an example of an advertisement subject table. 
         FIG. 8  A diagram illustrating an example of an advertisement data table. 
         FIG. 9  A diagram illustrating an example of evaluation values of classification information. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     A description is now given of an embodiment mode (hereinafter referred to as embodiment) for carrying out the present invention, referring to the drawings. 
       FIG. 1  illustrates a system configuration diagram of an e-book advertisement system  1  according to this embodiment. As illustrated in  FIG. 1 , the e-book advertisement system  1  includes an e-book provision server  3 , a client device  10 , and an advertisement data delivery server  20 . The e-book provision server  3 , the client device  10 , and the advertisement data delivery server  20  are respectively connected to one another for data communication via a network  5  such as the Internet. 
     The e-book provision server  3  is a computer which stores one or more e-books, and when the e-book provision server  3  receives a delivery request for an e-book (such as a purchase request for an e-book) from the client device  10 , provides the client device  10  with the requested e-book. Note that, the e-book according to this embodiment is data obtained by digitizing a book, a magazine, or the like, and the e-book includes text pages for showing contents of the e-book and advertisement pages for placing advertisements. Note that, the advertisement page is a page provided with a display area for advertisements in at least a part thereof. 
     The client device  10  is a computer having functions of receiving an e-book from the e-book provision server  3 , and displaying the received e-book in response to an operation of a user. According to this embodiment, the client device  10  includes a touch panel  12  functioning as display means and input receiving means, and displays the contents of the e-book on the touch panel  12 . 
     The advertisement data delivery server  20  is a computer for selecting, based on a browsing history of the user for the e-book recorded in the client device  10 , advertisement data to be displayed on advertisement pages included in the e-book, and delivering the selected advertisement data to the client device  10 . On the client device  10 , the contents of the advertisement pages are updated based on the advertisement data delivered from the advertisement data delivery server  20 . 
     Referring to a sequence diagram illustrated in  FIG. 2 , a description is now given of an example of processing carried out on the e-book advertisement system  1 . 
     As illustrated in  FIG. 2 , the client device  10  requests the e-book provision server  3  to deliver an e-book (S 1001 ), and receives (downloads) the e-book from the e-book provision server  3  (S 1002 ). 
       FIG. 3  illustrates an example of the e-book received by the client device  10 . The e-book illustrated in  FIG. 3  includes 1st to N-th pages, and each page is denoted by P i . On this occasion, in the example illustrated in  FIG. 3 , P 1 , P 2 , P n+1 , and the like represent text pages of the e-book, and P n , P n+m , and the like represent advertisement pages showing advertisements. In a state in which the client device  10  has just received the e-book, advertisements on the advertisement pages are advertisements in an initial state, and the advertisement in the initial state includes a state in which no advertisements are placed. 
     A description now returns to the sequence diagram in  FIG. 2 . On the client device  10 , in response to an operation received by the touch panel  12  from the user, a page included in the received e-book is displayed on the touch panel  12  (S 1003 ). On the client device  10 , when an operation for switching the page displayed on the touch panel  12  is received (Y in S 1004 ), the page is switched and displayed (S 1005 ), and when an operation for zooming in a part of the page displayed on the touch panel  12  is received (Y in S 1006 ), the part of the page is zoomed in and is displayed (S 1007 ). For example, the switching operation for a page may be carried out by moving a finger from a state in which the finger is touched on a display area of the displayed page toward a direction of a destination page (so called flicking), and the zooming operation for a page may be carried out by, while a plurality of fingers are in contact with an area to be zoomed out of the displayed page, extending a gap between the fingers (so called pinching out). 
     The client device  10  records history data on the pages that have been displayed on the touch panel  12 , and the zoomed-in part (S 1008 ). The history data on the pages may include periods for which the pages are displayed, and the number of times of the display. The history data on the zoomed-in part may include position information (for example, area information such as coordinate ranges, or an upper left position and a lower right position), a period of display, and the number of times of the display on the zoomed-in part. 
     When the client device  10  determines that a transmission timing at which the recorded history data is to be transmitted to the advertisement data delivery server  20  has not been reached (N in S 1009 ), the client device  10  returns to S 1004 , and repeats the subsequent processing. When the client device  10  determines that the transmission timing has been reached (Y in S 1009 ), the client device  10  transmits the recorded history data to the advertisement data delivery server  20  (S 1010 ). Note that, the history data transmitted from the client device  10  to the advertisement data delivery server  20  includes identification information on the e-book. Moreover, the transmission timing may be, for example, a timing at which a predetermined period has elapsed after the e-book is displayed, a timing for communication to/from the advertisement data delivery server  20 , a timing at which the number of recorded pages reaches a predetermined value, a timing at which a history of a text page determined in advance for an advertisement page included in the e-book is recorded, a timing at which browsing has reached a page determined in advance (or a timing at which all pages have been browsed) for the e-book, a timing for receiving a program or data from the e-book provision server  3  or the advertisement data delivery server  20 , a timing at which a browser program for the e-book is started or stopped, and a timing at which communication is available. 
     The advertisement data delivery server  20  selects advertisement data based on the history data transmitted from the client device  10  (S 1011 ). The advertisement data delivery server may store advertisement subjects (such as classification information on products and services to be advertised) in each page and each part of the page for each e-book, select an advertisement subject based on the history data received from the client device  10 , and acquire advertisement data associated with the selected advertisement subject. For example, based on the history data received from the client device  10 , when shoes are selected as the advertisement subject, the advertisement data delivery server  20  acquires advertisement data determined in advance for the shoes. The processing of selecting advertisement data is described in detail later. 
     The advertisement data delivery server  20  transmits the selected advertisement data to the client device  10  (S 1012 ). On the client device  10 , based on the advertisement data received from the advertisement data delivery server  20 , advertisement pages in the e-book are updated (S 1013 ). 
       FIGS. 4A and 4B  illustrate examples of the e-book after advertisement pages are updated. For example, a page to be updated by the advertisement data received from the advertisement data delivery server  20  may be at least one of advertisement pages which the user has not browsed on the client device  10 .  FIG. 4A  illustrates an example of updated advertisement pages when pages starting from the page P m  have not been browsed. In the example illustrated in  FIG. 4A , both P n  and P n+m  are updated, but one of them may be updated, or when there are a plurality of pieces of received advertisement data (for example, advertisements for shoes A and shoes B as “shoes” are acquired), different advertisements may be displayed on P n  and P n+m . Moreover,  FIG. 4B  illustrates an example of an updated advertisement page when the page P n  has already been browsed and pages starting from P n+m  have not been browsed. In the example illustrated in  FIG. 4B , P n  is not updated, and only P n+m  is updated. 
     A flow of processing based on the sequence illustrated in  FIG. 2  has been described above. A description is now given of an example of functions provided in the client device  10  and the advertisement data delivery server  20  in order to realize the above-mentioned processing, referring to a functional block diagram illustrated in  FIG. 5 . 
     First, a description is given of functions provided in the client device  10 . As illustrated in  FIG. 5 , the client device  10  includes an e-book storage module  100 , an e-book acquisition module  102 , an operation information reception module  104 , a display module  106 , a display control module  108 , a browsing history data recording module  110 , a browsing history data transmission module  112 , an advertisement data reception module  114 , and an advertisement page update module  116 . 
     Functions of the above-mentioned modules provided in the client device  10  may be realized by a computer, which is provided with hardware such as control means including a CPU, storage means such as a memory, communication means such as a communication interface for transmitting/receiving data to/from external devices, and the touch panel  12 , reading and executing a program stored in a computer-readable information storage medium. Note that, the program may be provided to the client device  10  via an information storage medium such as an optical disc, a magnetic disk, a magnetic tape, a magneto-optical disc, or a flash memory, or provided to the client device  10  via a data communication network such as the Internet. 
     The e-book storage module  100  is realized by storage means such as a semiconductor memory or a magnetic disk, and stores the e-books received from the e-book provision server  3 . 
     The e-book acquisition module  102  acquires an e-book including text pages and advertisement pages. The e-book acquisition module  102  may acquire an e-book by reading the e-book stored in the e-book storage module  100 , or may acquire an e-book by receiving the e-book from the e-book provision server  3 . 
     The operation information reception module  104  receives information on an operation carried out by the user on the client device  10 . According to this embodiment, the operation information reception module  104  detects a position of contact by the user on the touch panel  12  provided to the client device  10  and a change in the contact position, and determines, based on the detected contact position and change in the contact position, the operation information on the user. For example, the operation information reception module  104  receives various operations such as an operation of selecting an e-book, an operation of switching a displayed page of an e-book, and an operation of zooming in a part of a displayed page of an e-book. As described above, the switching operation for a page may be carried out by moving a finger from a state in which the finger is touched on the touch panel  12  displaying a displayed page toward a direction of a destination page (so called flicking), and the zooming operation for a page may be carried out by, while a plurality of fingers are in contact with the touch panel  12  displaying a displayed page, extending a gap between the fingers (so called pinching out). Of course, the respective operation methods are not limited to the above-mentioned methods, and other methods may be used. For example, a display object (such as an icon or a button) used for proceeding to a next page, a display object used for returning to a previous page, and a display object used for instructing zooming in/out may be provided on each of pages of an e-book, and, by selecting (for example, depressing) these display objects, the operation of switching a page and the operation of zooming in/out a page may be carried out. 
     The display module  106  is realized by a display such as the touch panel  12 , and displays apart of a page included in the e-book selected by an operation received by the operation information reception module  104 . For example, on the display module  106 , one page of the e-book may be displayed for each time, or two facing pages of the e-book may be displayed. A three-axis acceleration sensor may be provided on the client device  10  so that an inclination of the client device  10  may be detected based on an acceleration detected by the acceleration sensor, and, depending on the detected inclination, the display may be switched between one page of the e-book each time and two facing pages of the e-book. 
     The display control module  108  provides control of switching or zooming in a page of the e-book displayed on the display module  106  in response to an operation of the user received by the operation information reception module  104 . Specifically, when the operation information reception module  104  receives the operation of switching a page displayed on the display module  106 , the display control module  108  causes the display module  106  to switch and display the displayed page. Moreover, when the operation information reception module  104  receives the operation of zooming a part of a page displayed on the display module  106 , the display control module  108  causes the display module  106  to zoom in and display the part of the page specified by the operation. 
     The browsing history data recording module  110  records browsing history data including the history regarding pages and zoomed-in parts of the e-books displayed on the display module  106 . For example, when an entire page is displayed on the display module  106 , the browsing history data recording module  110  records information on the page and a period of display of the page in association with each other. Moreover, when a part of the page is zoomed in and is displayed on the display module  106 , the browsing history data recording module  110  records information on the zoomed-in part and a period of display of the zoomed-in part in association with each other. The information on the zoomed-in part may include information on the page, and position information (such as coordinate information, area information, and information on a zoomed-in object) of the zoomed-in part in the page. 
       FIG. 6  illustrates an example of the browsing history data recorded by the browsing history data recording module  110 . In the example illustrated in  FIG. 6 , identification information (e-book ID) of the e-book displayed on the display module  106 , information on the displayed page (page number), a displayed part (display part), a period of display, and a date and a time of recording are recorded in association with one another. The browsing history data recording module  110  may determine that the area information of the display part on the page is “upper” when a part (display part) zoomed in and displayed on the touch panel  12  corresponds to an upper half part of the page, “lower” when the part corresponds to a lower half part of the page, and “upper left” when the part corresponds to the upper half and a left half of the page, and may store the determined area information in a field of the display part. Alternatively, the browsing history data recording module  110  may store a coordinate range (for example, [(x 1 , y 1 ), (x 2 , y 2 )] indicates a rectangular area having an upper left corner at (x 1 , y 1 ) and a lower right corner at (x 2 , y 2 )) of the display part in a page coordinate system (in which, for example, an upper left corner of the page is an origin, the horizontal direction is an X axis, and the vertical direction is a Y axis) in the field of the display part. Note that, the browsing history data recorded by the browsing history data recording module  110  is not limited to the above-mentioned example, and the browsing history data recording module  110  may record, for example, in place of or in addition to the period of display, the number of times of display on the display module  106 . 
     The browsing history data transmission module  112  transmits the browsing history data recorded by the browsing history data recording module  110  to the advertisement data delivery server  20 . The browsing history data transmission module  112  may determine whether or not a transmission timing for the browsing history data has been reached, and, when the browsing history data transmission module  112  determines that the transmission timing has been reached, the browsing history data transmission module  112  may transmit the history data recorded up to that timing by the browsing history data recording module  110  to the advertisement data delivery server  20 . For example, the transmission timing may be a timing at which a predetermined period has elapsed after the e-book is displayed, a timing for communication to/from the advertisement data delivery server  20 , a timing at which a sum of recorded periods of display exceeds a threshold, a timing at which the number of browsed pages reaches a predetermined value, a timing at which a history of a text page determined in advance for each advertisement page included in the e-book is recorded, a timing at which browsing has reached a page determined in advance (or a timing at which all pages have been browsed) for the e-book, a timing for receiving a program or data from the e-book provision server  3  or the advertisement data delivery server  20 , a timing at which a browser program for the e-book is started or stopped, and a timing at which communication is available. Note that, the browsing history data transmission module  112  may transmit, each time the above-mentioned transmission timing has been reached, the browsing history data to the advertisement data delivery server  20 . 
     The advertisement data reception module  114  receives, based on the browsing history data transmitted by the browsing history data transmission module  112  to the advertisement data delivery server  20 , advertisement data selected by the advertisement data delivery server  20 . 
     The advertisement data update module  116  updates, based on the advertisement data received by the advertisement data reception module  114 , at least one advertisement page. The advertisement page update module  116  may select, for example, at least one of advertisement pages of the e-book for which the browsing history is not recorded by the browsing history data recording module  110 , and may overwrite an advertisement in the selected advertisement page with the received advertisement data. Moreover, the advertisement page update module  116  may select, based on the size of an advertisement of the advertisement data received by the advertisement data reception module  114 , an advertisement page which is subject to the update out of advertisement pages included in the e-book. For example, the advertisement page update module  116  may select an advertisement page to be updated out of advertisement pages in which an advertisement display area in the advertisement page is larger than the size of the advertisement of the received advertisement data (namely, in which an advertisement may be placed without any part thereof extending out of the advertisement page) out of the advertisement pages included in the e-book. 
     Moreover, when a degree of importance is defined for the advertisement data received by the advertisement data reception module  114 , the display control module  108  may control the display module  106  to display an advertisement based on advertisement data for a period equal to or longer than a period corresponding to the degree of importance. For example, in a case where there are three levels of importance: high (display for ten seconds), intermediate (display for three seconds), and a low (without control), when the level of importance of received advertisement data is “high”, the display control module  108  may prohibit the switching of an advertisement page based on the advertisement data for 10 seconds, or may repeat the display of the advertisement page based on the advertisement data so that the advertisement page is displayed for 10 seconds in total. 
     A description is now given of functions provided in the advertisement data delivery server  20 . As illustrated in  FIG. 5 , the advertisement data delivery server  20  includes an advertisement data storage module  200 , a browsing history data reception module  202 , an advertisement data selection module  204 , and an advertisement data transmission module  206 . 
     Functions of each of the above-mentioned components provided in the advertisement data provision server  20  may be realized by a computer, which is provided with hardware including control means such as a CPU, storage means such as a memory, and communication means such as a communication interface for transmitting/receiving data to/from external devices, reading and executing a program stored in a computer-readable information storage medium. Note that, the program may be provided to the advertisement data provision server  20  via an information storage medium such as an optical disc, a magnetic tape, a magneto-optical disc, or a flash memory, or provided to the advertisement data provision server  20  via a data communication network such as the Internet. 
     The advertisement data storage module  200  stores, for each of the e-books, an advertisement subject (such as attribute information on an product or a service to be advertised) associated with each page and each part of the page (zoomed-in part) of the e-book, and stores advertisement data for each of advertisement subjects. 
       FIG. 7  illustrates an example of an advertisement subject table for each e-book to be stored in the advertisement data storage module  200 . As illustrated in  FIG. 7 , in the advertisement subject table, identification information on the e-book (e-book ID), a number of a page in the e-book, a display part of the page (full or partial), and classification information (genre information) on a product and a service which are subject to advertisement are stored in association with one another. For example, as data to be stored in the display part, a coordinate range of the display part in a page coordinate system (in which, for example, an upper left corner of the page is an origin, the horizontal direction is an X axis, and the vertical direction is a Y axis), for example, “upper” when the display part corresponds to an upper half part of the page, “lower” when the display part corresponds to a lower half part of the page, and “upper left” when the display part corresponds to the upper half and a left half of the page, may be stored in the field for the display part. 
       FIG. 8  illustrates an example of the advertisement data table storing advertisement data corresponding to each piece of classification information stored in the advertisement data storage module  200 . As illustrated in  FIG. 8 , in the advertisement data table, in association with the classification information, identification information on advertisement data (advertisement ID) and information on format (format information) of the advertisement data storing a data format and a size of the advertisement data are stored. Note that, actual data of the advertisement data is associated with the advertisement ID, and is stored in the advertisement data storage module  200 . 
     The browsing history data reception module  202  receives the browsing history data transmitted by the browsing history data transmission module  112  of the client device  10 . 
     The advertisement data selection module  204  selects advertisement data from the advertisement data storage module  200  based on the browsing history data received by the browsing history data reception module  202 . A description is now given of an example of processing of selecting advertisement data by the advertisement data selection module  204 . 
     The advertisement data selection module  204  refers to, based on an e-book ID included in the browsing history data, a corresponding advertisement subject table in the advertisement data storage module  200 . Then, the advertisement data selection module  204  identifies classification information to which each of sets of a page number and a display part included in the browsing history data corresponds. For example, in the advertisement subject table illustrated in  FIG. 7 , for a set of the e-book ID=D0001, the page number=2, and the display part=upper, the classification information=shoes is identified. In a case where a coordinate range (referred to as recorded coordinate range) is stored in the display part in the browsing history data, a record storing a corresponding coordinate range out of coordinate ranges (referred to as set coordinate ranges) stored in the advertisement subject table may be selected. On this occasion, for example, the advertisement data selection module  204  may extract set coordinate ranges having the same e-book ID and page number as those of the recorded coordinate range, and, out of the extracted set coordinate ranges, may select a set coordinate range having the maximum overlap with the recorded coordinate range, or may select set coordinate ranges having a ratio of the overlap with the recorded coordinate range equal to or larger than a predetermined value. Then, the advertisement data selection module  204  calculates, for each page and each zoomed-in part of a page included in the browsing history data, an evaluation value for each piece of the associated classification (genre) information in the referred advertisement subject table. 
     The evaluation value for each piece of the classification information may be calculated by, for example, summing products each of which is a period of display (or number of times of display)*a weight of page (or zoomed-in part) for a page (or zoomed-in part) stored in each of the records included in the history data. When the weight of the page is 1, the weight of a zoomed-in part may be w (&gt;1), and the value of w may be fixed or may be a variable corresponding to a zooming-in ratio. Then, the advertisement data selection module  204  selects pieces of classification information each having an calculated evaluation value, which is equal to or higher in position of descending order than a predetermined position or larger than a threshold out of the pieces of classification information, and acquires advertisement data of advertisement IDs in the advertisement data table associated with the selected pieces of classification information. 
       FIG. 9  illustrates, for the browsing history data illustrated in  FIG. 6 , an example of evaluation values for respective pieces of classification information calculated for the advertisement subject table illustrated in  FIG. 7 . In the example illustrated in  FIG. 9 , the evaluation values are calculated under a condition that the weight for the zoomed-in part w is 3. When, in the example illustrated in  FIG. 9 , classification information having the maximum evaluation value is selected, the classification information “shoes” is selected. Then, based on the example of the advertisement table illustrated in  FIG. 8 , the advertisement data selection module  204  acquires advertisement data having advertisement IDs “AD0002” and “AD0003” associated with the classification information “shoes”. 
     The advertisement data transmission module  206  transmits the advertisement data selected by the advertisement data selection module  204  to the client device  10  which has transmitted the browsing history data used for the selection of the advertisement data. 
     According to the above-mentioned e-book advertisement system  1 , contents of advertisements placed in the e-book can be updated based on the contents the user has browsed and has paid attention to in the e-book. Moreover, according to the e-book advertisement system  1 , based on the browsing history of the user, by updating advertisements placed on advertisement pages which the user has not browsed, possibility that the user views the updated advertisements is increased, and the advertisements having contents of interest to the user can be quickly provided. Moreover, according to the e-book advertisement system  1 , advertisements having contents which the user has browsed for a long period and a large number of times can be provided to the user. Moreover, according to the e-book advertisement system  1 , a part zoomed in and browsed by the user out of the e-book is evaluated as a subject of particular interest to the user, and advertisements selected based on the evaluation result can be provided to the user. Moreover, according to the e-book advertisement system  1 , a period for which the user is browsing an advertisement can be controlled so as to guarantee a period requested by a provider of the advertisement. 
     The present invention is not limited to the above-mentioned embodiment. For example, the e-book advertisement system  1  has been described by using the example in which the e-book provision server  3  and the advertisement data delivery server  20  are configured as independent devices, but the e-book provision server  3  and the advertisement data delivery server  20  may be configured as a single device. 
     Moreover, the client device  10  may be provided with, along with the e-book, the advertisement subject table for the e-book, and, in the client device  10 , based on the browsing history data recorded by the browsing history data recording module  110 , the evaluation value for each of advertisement subject (classification information) may be calculated. Then, the client device  10  may select advertisement subjects based on the calculated evaluation values, and may transmit the selection results to the advertisement data delivery server  20 . In this configuration, the client device  10  may record a history of a period of display and the number of times of display for each of the advertisement subjects. 
     Moreover, the client device  10  may be provided with, along with the e-book, all of the advertisement subject table, the advertisement data table, and the advertisement data for the e-book, thereby providing the client device  10  with the functions of the advertisement data selection module  204 . With this configuration, the necessity of communication to/from the advertisement data delivery server  20  is eliminated, and hence even if the client device  10  cannot connect to the network, contents of advertisements placed on advertisement pages in the e-book can be updated based on the browsing history of the user. 
     Moreover, in the above-mentioned embodiment, there has been described the example in which, based on the browsing history of the e-book, advertisement pages in the e-book are updated, but text pages of the e-book may be updated. In this case, pages based on data acquired based on the browsing history of the e-book may be added to the e-book, or at least a part of text pages included in the e-book may be replaced by pages based on the data. Of course, in a case where the form of updating text pages of the e-book is employed, the e-book may not include advertisement pages. 
     Moreover, in the embodiment, the example using the tablet computer having the touch panel  12  as the client device  10  has been described, but it should be understood that, as the client device  10 , a stationary or portable personal computer, a mobile phone, a personal digital assistant, a game machine, or the like may be used.