Patent Publication Number: US-2022218266-A1

Title: Rehabilitation support apparatus, method therefor, and program

Description:
This application is based upon and claims the benefit of priority from Japanese patent application No. 2020-77811, filed on Apr. 24, 2020, the disclosure of which is incorporated herein in its entirety by reference. 
     TECHNICAL FIELD 
     The present invention relates to a rehabilitation support apparatus, a method therefor, and a program. 
     BACKGROUND ART 
     In the above technical field, patent literature 1 discloses a system configured to support rehabilitation. 
     CITATION LIST 
     Patent Literature 
     
         
         Patent literature 1: Japanese Patent Laid-Open No. 2015-228957 
       
    
     SUMMARY OF THE INVENTION 
     Technical Problem 
     However, in the technique described in the above literature, it is impossible to control a load to be given to the cognitive function of a user in rehabilitation. 
     The present invention enables to provide a technique of solving the above-described problem. 
     Solution to Problem 
     One example aspect of the invention provides a rehabilitation support apparatus for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     a detector that detects a three-dimensional rehabilitation action of a user; 
     a display controller that generates, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displays the avatar object and the target object on a display; 
     a notifier that notifies a generation position of the target object; and 
     a cognitive load controller that gives a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein to control the cognitive load to be given to the user, the cognitive load controller changes the predetermined time by an operation of an operator. 
     Another example aspect of the invention provides a rehabilitation support apparatus for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     a detector that detects a three-dimensional rehabilitation action of a user; 
     a display controller that generates, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displays the avatar object and the target object on a display; 
     a notifier that notifies a generation position of the target object; and 
     a cognitive load controller that gives a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein to control the cognitive load to be given to the user, the cognitive load controller causes at least two target objects to simultaneously exist in the three-dimensional virtual space. 
     Still other example aspect of the invention provides a rehabilitation support apparatus for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     a detector that detects a three-dimensional rehabilitation action of a user; 
     a display controller that generates, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displays the avatar object and the target object on a display; 
     a notifier that notifies a generation position of the target object; and 
     a cognitive load controller that gives a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein to control the cognitive load to be given to the user, the cognitive load controller changes a background image other than the target object to be displayed on the display. 
     One example aspect of the invention provides a rehabilitation support method for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, the predetermined time is changed by an operation of an operator. 
     Another example aspect of the invention provides a rehabilitation support method for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, at least two target objects are caused to simultaneously exist in the three-dimensional virtual space. 
     Still other example aspect of the invention provides a rehabilitation support method for recovering one of cognitive impairment and a higher brain dysfunction, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, a background image other than the target object to be displayed on the display is changed. 
     One example aspect of the invention provides a rehabilitation support program for recovering one of cognitive impairment and a higher brain dysfunction, the program causing a computer to execute a method, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, the predetermined time is changed by an operation of an operator. 
     Another example aspect of the invention provides a rehabilitation support program for recovering one of cognitive impairment and a higher brain dysfunction, the program causing a computer to execute a method, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, at least two target objects are caused to simultaneously exist in the three-dimensional virtual space. 
     Still other example aspect of the invention provides a rehabilitation support program for recovering one of cognitive impairment and a higher brain dysfunction, the program causing a computer to execute a method, comprising: 
     detecting a three-dimensional rehabilitation action of a user; 
     generating, in a three-dimensional virtual space, an avatar object that moves in accordance with the detected rehabilitation action and a target object to be visually recognized by the user and displaying the avatar object and the target object on a display; 
     notifying a generation position of the target object; and 
     giving a cognitive load to the user by generating the target object after an elapse of a predetermined time from the notification of the generation position of the target object, 
     wherein in the giving, to control the cognitive load to be given to the user, a background image other than the target object to be displayed on the display is changed. 
     Advantageous Effects of Invention 
     According to the present invention, it is possible to control a load to be given to the cognitive function of a user in rehabilitation. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram showing the configuration of a rehabilitation support apparatus according to the first example embodiment; 
         FIG. 2A  is a block diagram showing the configuration of a rehabilitation support apparatus according to the second example embodiment; 
         FIG. 2B  is a view showing the task database configuration of the rehabilitation support apparatus according to the second example embodiment; 
         FIG. 3  is a view showing an example of the display screen of the rehabilitation support apparatus according to the second example embodiment; 
         FIG. 4  is a view showing an example of the display screen of the rehabilitation support apparatus according to the second example embodiment; and 
         FIG. 5  is a view showing an example of the display screen of the rehabilitation support apparatus according to the second example embodiment. 
     
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Example embodiments of the present invention will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components, the numerical expressions and numerical values set forth in these example embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. 
     First Example Embodiment 
     A rehabilitation support apparatus  100  according to the first example embodiment of the present invention will be described with reference to  FIG. 1 . 
     The rehabilitation support apparatus  100  includes a detector  101 , a display controller  102 , a notifier  103 , and a cognitive load controller  104 . 
     The detector  101  detects the direction of the head of a user  130  who wears a head mounted display  120 , and a three-dimensional rehabilitation action. 
     The display controller  102  generates, in a three-dimensional virtual space  150 , avatar objects  151  that move in accordance with a detected rehabilitation action and a target object  152  to be visually recognized by the user  130 . The display controller  102  then displays the objects on the head mounted display  120  in accordance with the direction of the head of the user  130  detected by the detector  101 . 
     The notifier  103  notifies the user of the generation of the target object  152 . For example, in  FIG. 1 , the notifier  103  displays, as a notification image  153 , a radar screen image used to notify the user of the generation position of the target object  152 . The radar screen image indicates the direction in which the target object  152  is located relatively with respect to a reference direction (initially set in the front direction of the user who is sitting straight on a chair) in the virtual space. The radar screen image also indicates the direction in which the head of the user  130  is located relatively with respect to the reference direction. 
     The cognitive load controller  104  generates the target object  152  after the elapse of a predetermined time from the timing of notifying the generation of the target object  152 , thereby giving a cognitive load to the user  130 . 
     As described above, according to this example embodiment, the user needs to continuously memorize and hold a rehabilitation action that he/she should perform after notification of generation of the target object until actual generation of the target object. It is therefore possible to quantitatively adjust and control a cognitive load that should be subjected to information processing by the brain and then give it to the user. For example, when the type, number, size, spatial spread, position, amount, and the like of information included in a notification image or a notification sound are adjusted, a cognitive load that has increased the complexity of information to be memorized and held can be given. 
     Second Example Embodiment 
     A rehabilitation support system  200  according to the second example embodiment of the present invention will be described with reference to  FIG. 2A .  FIG. 2A  is a view for explaining the configuration of the rehabilitation support system  200  according to this example embodiment. 
     As shown in  FIG. 2A , the rehabilitation support system  200  includes a rehabilitation support apparatus  210 , two base stations  231  and  232 , a head mounted display  233 , and two controllers  234  and  235 . A user  220  sitting on a chair  221  twists the upper half body or stretches the hands in accordance with display on the head mounted display  233 , thereby making a rehabilitation action. In this example embodiment, a description will be made assuming rehabilitation performed while sitting on a chair. However, the present invention is not limited to this. Rehabilitation may be performed while standing, walking, running, or making another specific action. In addition, the controllers may be held on or attached to body parts other than hands, such as feet or trunk. 
     The two base stations  231  and  232  sense the motion of the head mounted display  233  and the motions of the controllers  234  and  235 , and send these to the rehabilitation support apparatus  210 . The rehabilitation support apparatus  210  performs display control of the head mounted display  233  while evaluating the rehabilitation action of the user  220 . Note that the head mounted display  233  can be of a non-transmissive type, a video see-through type, or optical see-through type. In this example embodiment, a virtual space of VR (Virtual Reality) is presented to the user. However, a physical space and a virtual space may be displayed in a superimposed manner, like AR (Augmented Reality), or physical information may be reflected on a virtual space, like MR (Mixed Reality). 
     In this example embodiment, as an example of a sensor configured to detect the position or action of the hand or head of the user, the controllers  234  and  235  held in the hands of the user  220 , and the base stations  231  and  232  have been described. However, the present invention is not limited to this. A camera (including a depth sensor) configured to detect the positions or action of the hands of the user by image recognition processing, a sensor configured to detect the positions of the hands of the user by a temperature, a wristwatch-type wearable terminal put on an arm of the user, a motion capture device, or the like can be applied to the present invention. 
     The rehabilitation support apparatus  210  includes an action detector  211 , display controllers  212  and  213 , an evaluator  214 , an updater  215 , a task set database  216 , and an operation unit  217 . 
     The action detector  211  acquires, via the base stations  231  and  232 , the positions of the controllers  234  and  235  held in the hands of the user  220 , and detects the rehabilitation action of the user  220  based on changes in the positions of the hands of the user  220 . 
     The display controller  212  generates, in a virtual space, avatar objects  241  that move in accordance with a detected rehabilitation action and a target object  242  representing the target of the rehabilitation action. The display controller  212  displays, on a display screen  240 , the images of the avatar objects  241  and the target object  242  in accordance with the direction and position of the head mounted display  233  detected by the action detector  211 . The images of the avatar objects  241  and the target object  242  are superimposed on a background image  243 . Here, the avatar objects  241  have the same shape as the controllers  234  and  235 . However, the present invention is not limited to this, and the size, shape, or color may be changed on the left and right sides. The avatar objects  241  move in the display screen  240  in accordance with the motions of the controllers  234  and  235 . The controllers  234  and  235  are each provided with at least one button and configured to perform various kinds of settings by operating the button. The background image  243  is cut out from a virtual space including a horizontal line  244  and a ground surface image  245 . 
     The display controller  212  displays the target object  242  while gradually changing its display position and size such that it falls downward from above the user  220 . The user  220  moves the controllers  234  and  235  to make the avatar objects  241  in the screen close to the target object  242 . Note that as for the moving direction of the target object, for example, the target object may be displayed such that it rises from the floor surface to above the head, or movement in the depth direction may occur in addition to the movement in the vertical direction. 
     If the shortest distance between the target object  242  and a sensor object (not shown here) included in the avatar object  241  falls within a predetermined range, the target is achieved, and the target object  242  disappears. At this time, if the shortest distance between the target object  242  and the sensor object included in the avatar object  241  is equal to or less than a first threshold, “excellent” is displayed because of the complete achievement of the target, and a corresponding voice is output to make feedback. The controllers  234  and  235  may simultaneously be vibrated. 
     On the other hand, if the shortest distance between the target object  242  and the sensor object included in the avatar object  241  is not less than the first threshold and not more than a second threshold, “well done” is displayed because of the achievement of the target, and a corresponding voice is output to make feedback. The controllers  234  and  235  may simultaneously be vibrated. 
     The action of the user  220  to move the controllers  234  and  235  is the rehabilitation action, and the display of the target object that urges the user  220  to do one rehabilitation action he/she should make is called a task. Information (task data) representing one task includes the appearance direction of the target object, the shape, the appearance position (the distanced from the user), the appearance interval (time interval), the moving speed in failing or rising, the size, the color, which one of the left and right controllers should be used to acquire a target object, the number of target objects that appear simultaneously, the size of the sensor object, and the like. 
     That is, the display controller  212  can also change (for example, in three levels), in accordance with task data, the distance from the user  220  to the fall position of the target object  242  in the depth direction. For example, a change can be made such that the target object falls quite near the user  220  or falls to a position that the user  220  cannot reach unless largely inclining the body forward. This can control an exercising load to be given to the user. 
     The display controller  213  displays a radar screen image  250  on the display screen  240  of the head mounted display  233 . The radar screen image  250  is a notification image used to notify the user of generation of the target object  242 . The radar screen image  250  notifies the user of the direction in which the generated target object  242  is located relatively with respect to a reference direction (initially set in the front direction of the user who is sitting straight on a chair) in the virtual space. The radar screen image  250  also notifies the user how far the position of the generated target object  242  is apart from the user  220 . Note that the notification image is not limited to the radar screen image, and the notification may be made using characters, an arrow, a symbol, an illustration, or a type, intensity, blinking, or the like of light or a color. The notification method is not limited to the image, and may use a voice, a vibration, or a combination of some of a voice, a vibration, and an image. 
     Independently of the direction of the head of the user  220 , the display controller  213  displays the radar screen image  250  at the center (for example, within the range of −50° to 50°) of the display screen  240  of the head mounted display  233 . However, the display portion is not limited to the center, and may be, for example, an arbitrary place on the four corners, the upper end, the lower end, the left end, and the right end of the screen. 
     The radar screen image  250  includes a head image  251  representing the head of the user viewed from above, a block image  252  obtained by dividing the periphery of the head image  251  into a plurality of blocks, and a fan-shaped image  253  as a visual field image representing the visual field of the user. A target position image representing the position of a target object is shown by coloring, blinking, or lighting a block in the block image  252 . This allows the user  220  to know whether the target object exists on the left side or the right side with respect to the direction in which he/she faces. Note that in this example embodiment, the block image  252  is fixed, and the fan-shaped image  253  moves. However, the present invention is not limited to this, and the block image  252  may be moved in accordance with the direction of the head while fixing the fan-shaped image  253  and the head image  251 . More specifically, if the head turns to the left, the block image  252  may rotate to right. 
     The evaluator  214  evaluates the rehabilitation action of the user in accordance with the amount and quality of the task achieved by the user  220  and adds a point. Here, the quality of the achieved task depends on “well done” or “excellent”, that is, how close the avatar object could be brought to the target object. The evaluator  214  adds different points to achieved tasks (a high point to a far object, and a low point to a close object). 
     The updater  215  updates a target task in accordance with the integrated point. For example, a target task may be updated using a task achievement ratio (the number of achieved targets/the number of tasks). 
     The task set database  216  stores a set of a plurality of tasks. The task set database  216  stores a task set that decides the order of providing the plurality of tasks to the user. 
     For example, task sets may be stored as templates for each hospital, or a history of executed task sets may be stored for each user. The rehabilitation support apparatus  210  may be configured to be communicable with another rehabilitation support apparatus via the Internet. In this case, one task set may be executed by the same user in a plurality of places, or various templates may be shared by a plurality of users in remote sites. 
     The operation unit  217  is provided to operate display control in the display controller  212  and the display controller  213 . 
     A cognitive load controller  218  generates the target object  242  after the elapse of a predetermined time from the timing of notifying the generation of the target object  242 , thereby giving a cognitive load to the user  220 . That is, the user needs to continuously memorize and hold an action that he/she should perform after he/she knows that the target object will be generated until actual generation of the target object. The “request to memorize” is a cognitive load for the user. The cognitive load controller  218  may control the cognitive load by changing a predetermined time from the timing of notifying the generation of the target object  242  to the timing of generating the target object  242 . 
     Also, the cognitive load controller  218  may control the cognitive load by changing the time not “until the timing of generating the target object  242 ” but “until the target object  242  approaches the range the user  220  can reach”. 
     The cognitive load controller  218  may give a cognitive load to the user  220  by displaying the background image  243  other than the target object  242  on the head mounted display  233 . 
       FIG. 2B  is a view showing a task table  260  stored in the task set database  216 . In the task table  260 , a time (task generation timing)  261 , a task interval  262 , a task position  263 , a task angle  264 , and a task distance (intensity)  265  are stored in linkage with a task ID. Also, in the task table  260 , a target object speed  266 , a perfect determination “excellent evaluation” criterion  267 , a good determination (well done evaluation) criterion  26   g   8 , a sensor object size  269 , and the like are stored in linkage with a task ID. In addition to these, a delay time (predetermined time) from task generation notification to task generation may be set for each task. 
       FIGS. 3 to 5  are views showing examples of display on the display screen  240  according to this example embodiment. In  FIGS. 3 and 4 , on a background image  301  representing a field, an image of a person representing a farmer is displayed as a trigger object  302  serving as a trigger of target object appearance. That is, the display controller  213  displays the trigger object  302  as a notification image used to notify the user of generation of the target object  242 . 
     When a predetermined time elapses after the trigger object  302  throws up a target object  303  in the shape of a potato, a target object  403  having the shape of a large potato appears from the upper side of the screen, as shown in  FIG. 4 . When the falling target object  403  is received by moving an avatar object  402  having the shape of a basket, the task is achieved. The left and right avatar objects  402  move on the screen in synchronism with the motions of the controllers  234  and  235 . 
     The cognitive load controller  218  generates the target object  403  after the elapse of a predetermined time from the timing at which the trigger object  302  throws up the target object  303  and notifies the generation of the target object  303 , thereby giving a cognitive load to the user  220 . Note that in synchronism with the motion of the trigger object  302 , generation of the target object may be notified at the same timing using a radar chart type notification image, or a notification by a voice may be combined. 
     In this way, the cognitive load controller  218  displays not a background including only a horizontal line as shown in  FIG. 2A  but a background image including a large quantity of information as shown in  FIGS. 3 and 4 , thereby giving a cognitive load to the user. That is, it is made difficult to memorize that the target object  401  has appeared, and the position to which the target object  401  is expected to fall, thereby giving a load closer to a cognitive load necessary in a real life to the user of rehabilitation. 
     In particular, the cognitive load controller  218  changes at least a part of the background image  301  along with time, thereby giving a cognitive load to the user  220 . In the example shown in  FIG. 3 , for example, in the background image  301 , a cloud  304  may be moved, plants  305  may be shaken, or an animal (not shown) irrelevant to the target object may be made to appear. This can impede concentration to the target object  303  and make it more difficult for the user  220  to memorize the position to which the target object  303  is expected to fall. More technically, it can be said that information irrelevant to the task is displayed on the background image to prepare an environment in which it is difficult to concentrate to the target object and intentionally cause an attention disorder (more specifically, a selective attention disorder, a divided attention disorder, an alternating attention disorder, or a sustained attention disorder), thereby making memorization difficult and controlling the cognitive load. 
       FIG. 5  is a view showing another example of display on the display screen  240  according to this example embodiment. In  FIG. 5 , in a background image  501  like woods, a trigger object  502  representing a monkey and a target object  503  representing an apple are displayed. When the trigger object  502  representing a monkey drops the target object  503  representing an apple from a tree, and the target object  503  approaching the user is received by moving an avatar object  504  representing a basket, the task is achieved. In this case as well, the cognitive load controller  218  starts dropping the target object  503  after the elapse of a predetermined time from the timing at which the trigger object  502  shakes the tree and notifies the generation of the target object  503 , thereby giving a cognitive load to the user  220  while causing an attention disorder. 
     Also, the cognitive load controller  218  causes at least two target objects  503  to exist in the three-dimensional virtual space and display these on the display screen  240 , thereby giving a cognitively stronger load to the user  220 . In other words, the cognitive load controller  218  generates the at least two target objects  503  at different positions in the left-and-right direction in the three-dimensional virtual space. That is, since the user  220  needs to memorize a plurality of points concerning at which position the trigger object  502  shakes the tree, a cognitively stronger load is given. 
     In particular, since the at least two target objects  503  are generated at a plurality of positions in a direction (the left-and-right direction in  FIG. 5 ) different from the moving direction (the falling direction in  FIG. 5 ) of the target object  503 , a larger cognitive load can be given. That is, since the user  220  needs to move the controllers  234  and  235  in consideration of the movement in the vertical direction, the difference between the generation positions in the left-and-right direction, and the difference in the failing position in the depth direction, the spatial cognitive ability is also tested. As described above, when the type, number, size, spatial spread, position, amount, and the like of information included in a notification image including a trigger object or a notification sound are adjusted in addition to the change of the predetermined time of the task, it is possible to quantitatively adjust and control the complexity of information to be memorized and held, that is, a cognitive load that should be subjected to information processing by the brain of the user. 
     The evaluator  214  evaluates the cognitive ability of the user based on whether the avatar object has reached, in a good timing, a three-dimensional target position represented by the target object, the time interval from target object generation notification to generation and the number of target objects, the degree of the attention disorder caused by the background image, and the like. 
     As described above, according to this example, it is possible to effectively control the load to be given to the cognitive function of the user in rehabilitation. More specifically, the memory and the cognitive processing ability of the user are tested quite naturally in a very easy task to receive a ball, a potato, or an apple, instead of memorizing something in accordance with an instruction for memorizing. For this reason, the psychological burden is small, and a rejection or an adverse reaction to rehabilitation, or a depressive reaction in case of a failure hardly occurs. By the rehabilitation action according to this example embodiment, it is possible to recover a so-called cognitive ability and a higher brain function (disorder) including a memory, a cognitive processing ability, a spatial cognitive ability, and an attention function (disorder) together with an exercise capacity and make a guidance such that the user can live his/her everyday life comfortably. 
     Note that in the example embodiment, a head mounted display is used. However, an eyeglass type display suffices. In place of the head mounted display, a hologram or a large TV type display may be arranged on the periphery of the user to urge the user to make a rehabilitation action. 
     OTHER EXAMPLE EMBODIMENTS 
     While the invention has been particularly shown and described with reference to example embodiments thereof, the invention is not limited to these example embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims. A system or apparatus including any combination of the individual features included in the respective example embodiments may be incorporated in the scope of the present invention. 
     The present invention is applicable to a system including a plurality of devices or a single apparatus. The present invention is also applicable even when an information processing program for implementing the functions of example embodiments is supplied to the system or apparatus directly or from a remote site. Hence, the present invention also incorporates the program installed in a computer to implement the functions of the present invention by the computer, a medium storing the program, and a WWW (World Wide Web) server that causes a user to download the program. Especially, the present invention incorporates at least a non-transitory computer readable medium storing a program that causes a computer to execute processing steps included in the above-described example embodiments.