JP4413150B2 - Service element switching method and program - Google Patents

Description

  The present invention has one or more service categories, each service category including one or more service elements, and executing at least a part of a service combining one service element selected from each category. The present invention relates to a service element switching method for switching a service element to another service element belonging to the same category.

  In recent years, with the advance of IT technology, many service elements (Web Service, Web page, device, content, sensor, etc.) can be accessed via a network. Research has been progressing on service composition technology that synthesizes these service elements according to the user's situation and preferences and provides basically necessary services (Non-Patent Document 1).

  This service composition technique realizes a composition service by discovering and binding service elements to be composed based on a service design drawing describing necessary functions.

  FIG. 5 schematically shows an example of a service design drawing. Here, the service design drawing is referred to as ST (Service Template), and the service element is referred to as SE (Service Element). In addition, in the example shown in FIG. 5, a unit in which the functions provided by the SE are semantically and abstractly categorized is called a service category. In the example shown in FIG. 5, a service has three categories: restaurant advertisement, translation, and output. The restaurant advertisement includes SE such as French cuisine and Chinese cuisine, the translation includes SE such as French → Japanese, English → Japanese, and the output includes SE elements such as TV and PDA (Personal Digital Assistant). It shows that there is.

  FIG. 6 is a schematic diagram of a conventional service composition system, and FIG. 7 is a sequence diagram of the service composition.

A plurality of SEs _{1 1} to 1 _n , an SE registry 2, and a service composition device 8 are connected to a network 6 such as the Internet.

SE1 ₁ to 1 _n are composed of SE description registrars and service entities. The SE registry 2 stores a plurality of SE descriptions. The SE description includes SE interface information (such as Web Service Description Language (WSDL) and UPnP (Universal Plug and Play) documents), service category name, SE metadata (SE name, location, price, provider name, etc.). Information representing the characteristics of The service composition device 8 includes a search unit 15 and an execution control unit 16.

Next, the operation of the system of FIG. 6 will be described with reference to FIG. 7. The SE description registrar registers the SE description in the SE registry 2. Here, when the user 7 inputs ST to the search unit 15 of the service composition device 8, the search unit 15 acquires category information from the input ST, and based on the category information, the necessary category information is obtained from the SE registry 2. The SE is searched, the SE description of the matching SE is acquired, and the SE description group is presented to the user 7. When the user 7 sees the SE description group presented and selects an SE to be used, the search unit 15 notifies the execution control unit 16 of the ST input by the user 7 and the selected SE description. Thereafter, the execution control unit 16 repeats the operation call to SE1, the reception of the operation return value, and the function parameter takeover operation.
M.M. Takemoto, T .; Ohishi, T .; Iwata, Y. et al. Yamato, Y. et al. Tanaka, K .; Shinno, S .; Tokumoto, and N.K. Shimamoto, “A Service-Composition and Service-Emergence Framework for Ubiquitous-Computing Environments,” Symposium on Applications and the Int. 313-318, Jan. 2004.

  However, in the above-described conventional technology, even if an SE is first synthesized to create a service suitable for the user, a part of SE is changed to another more optimal SE according to a change in the user's situation while the service is being executed. There was a problem that it was not possible to switch.

  For example, in the case of a service that outputs and displays content, for example, in the case of a service that outputs and displays content, the output SE is a TV if the user is at home, and a PDA if the user is moving. If you are on a business trip, you can consider switching the device that outputs content, such as a projector. Similarly, when the content to be displayed is a CM at a nearby restaurant, it is necessary to switch the content according to the movement.

  An object of the present invention is to provide an SE switching method and program capable of automatically switching an SE to a more appropriate SE during execution of a service.

In order to achieve the above object, an SE switching method of the present invention is an SE switching method performed in a service composition apparatus,
SE search in which the search means periodically searches for another SE belonging to the same category as the SE currently used for the service during service execution, and stores the profile description of the searched SE in the SE profile description holding means. Steps,
The scoring means periodically scores the SE stored in the SE profile description holding means, selects a better SE than the currently selected SE, and notifies that there is a more suitable SE Attaching step,
When the execution control means receives the notification, it takes over the state of the currently executing SE, calls the operation of the selected better SE, and switches the currently used SE to the selected better SE. And steps.

  The present invention searches for SEs belonging to the same category as the currently used SE at regular intervals in order to switch a part of the service SEs to more optimal SEs according to changes in the situation such as user movement. The searched SE is scored according to some evaluation criteria. As a result of scoring, if there is a better SE than the currently selected SE, the SE of the service being executed is switched to a better SE, and the execution of the service is continued.

  According to the embodiment of the present invention, the scoring step includes a user scoring function for each category of each single evaluation criterion, which is a function of user context information representing user status and preferences, and profile information of the SE. A value obtained by multiplying the weights of the single evaluation criteria for all the single evaluation criteria is used as the score of the SE, thereby enabling more appropriate SE selection.

  According to another embodiment of the present invention, when the current SE is selected, the scoring means selects an SE that has a lower score than the SE or an SE that has not been found by this scoring. When these points become higher than the currently selected SE, the execution control means is notified as the selected better SE. As a result, frequent switching of SEs can be avoided.

  The present invention can automatically switch the SE to a more appropriate SE during service execution.

  Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a system configuration diagram showing an embodiment of the present invention. A plurality of SEs _{1 1} to 1 _n , an SE registry 2, a context holding device 3, a context detection device 4, and a service composition device 5 are connected to a network 6 such as the Internet.

SE1 ₁ to 1 _n are composed of SE description registrars and service entities. The SE registry 2 stores a plurality of SE descriptions.

  The context holding device 3 holds a user context. The user context is a group of information that represents the user's situation and preferences, and includes various data such as the current position, time, money, and hobbies, for example.

  The context detection device 4 collects the context by the context collection unit 17 and periodically updates the context held in the context holding device 3. As the context detection device 4, for example, a commercially available GPS (Global Positioning System) can be used.

  The service composition device 5 includes a search unit 11, an SE description holding unit 12, a scoring unit 13, and an execution control unit 14. During execution of the service, the search unit 11 periodically searches other SEs belonging to the same category as the SE currently used for the service from the SE registry 2, and stores SE metadata stored in the SE description storage unit. 12. The scoring unit 13 is stored in the SE description holding unit 12 in order to switch a part of SEs to an optimum SE according to a change in the situation such as the movement of the user 7 while the service is being executed. If there is an SE with a higher score than the currently selected SE, the execution control unit 14 is notified of this (SE switching event). When the execution control unit 14 is notified of the SE switching event from the scoring unit 13, the execution service is temporarily interrupted, the state of the currently executing SE is taken over, and the new SE notified from the scoring unit 13 is received. Call operation and switch to new SE.

  Here, the scoring of the SE in the scoring unit 13 will be described in detail. The SE score is determined by the three items shown in FIG. 2, which are user evaluation criteria, user context information, and SE metadata. All of these are expressed by a combination of a plurality of data.

The user evaluation standard is expressed by a combination of several simple evaluation standards (one evaluation standard, for example, close position and low price). The user can customize the evaluation criteria by assigning weights to these single evaluation criteria as shown in FIG. The single evaluation criteria and the scoring function of the single evaluation criteria are registered in the scoring unit 13, but may be registered in a database (not shown) on the network 6. The user context and SE metadata are as described above. The scoring function is completely different depending on each single evaluation criterion. For example, as a scoring function based on a single evaluation criterion of closeness of distance, f (current location, SE position) = exp (− (user north latitude−SE north latitude) ^ 2
-(User East-SE East) ^ 2)
Can be considered. Of course, other functions may be used.

  During service execution, the kth SE score of service category j is expressed as follows using the above three pieces of information.

  By the way, the user evaluation criteria and the SE metadata are different for each service category. Therefore, it is desirable for the user to weight each category, but this places a heavy burden on the user. Therefore, it may be in the form of scoring with a common evaluation standard set and SE metadata independent of the service category.

In addition, when switching of SE occurs frequently, it is rather troublesome, and switching should not be performed unless it can be objectively evaluated that the SE is more suitable than the current SE. Therefore, switching is performed when an SE having a higher score than the currently used SE appears, and in other cases, the same SE as the current SE is used as it is. That is, as shown in FIG. 3, newly found SE (SE newly registered during service execution)
-SE that is higher than the current SE due to a reversal of rank compared to the previous evaluation
It is reasonable to switch SE only when there is any.

  FIG. 4 shows an SE scoring and switching sequence in the present embodiment.

  During execution of the service, the search unit 11 periodically searches other SEs belonging to the same category as the SE currently used for the service from the SE registry 2, and stores the metadata of the searched SE in the SE description holding unit. 12. The scoring unit 13 acquires the user context from the context holding device 3 and the SE metadata from the SE description holding unit 12 and periodically repeats the operation of scoring SE. During this time, the context is sequentially collected by the context collection unit 17 of the context detection device, and the context in the context holding device 3 is updated. When there is an SE with a higher score than the currently selected SE, the SE switching event is notified to the execution control unit 14. In response to the SE switching event from the scoring unit 13, the execution control unit 14 temporarily interrupts the service being executed, takes over the state of the currently executing SE, and receives the new SE notified from the scoring unit 13. Call operation and switch to new SE.

  In addition to the functions of the service composition apparatus 5 realized by dedicated hardware, a program for realizing the functions is recorded on a computer-readable recording medium, and the program recorded on the recording medium is recorded. It may be read by a computer system and executed. Here, the computer-readable recording medium refers to a recording medium such as a flexible disk, a magneto-optical disk, and a CD-ROM, and a storage device such as a hard disk device built in the computer system. Further, the computer-readable recording medium is a case where a program is transmitted via the Internet or the like. This includes a program that dynamically holds a program for a short time (a transmission medium or a transmission wave) and a program that holds a program for a certain period of time, such as a volatile memory inside a computer system serving as a server in that case.

It is a system configuration figure of one embodiment of the present invention. It is an image figure of scoring of SE using a context, a user evaluation standard, and SE metadata. It is explanatory drawing of switching of SE by periodic scoring. FIG. 2 is a sequence diagram of SE scoring and switching in the system of FIG. 1. It is a figure which shows an example of a service design drawing typically. It is a block diagram of the conventional system. It is a sequence diagram which shows operation | movement of the system of FIG.

Explanation of symbols

1 SE
2 SE Registry 3 Context Holding Device 4 Context Detection Device 5 Service Synthesis Device 6 Network 7 User 8 Service Synthesis Device 11 Search Unit 12 SE Description Holding Unit 13 Scoring Unit 14 Execution Control Unit 15 Search Unit 16 Execution Control Unit 17 Context Collection Unit

Claims (2)

Having one or more service categories, each service category including one or more service elements, and executing at least some service elements in combination with one service element selected from each category; A service element switching method performed by a service composition device that switches to another service element belonging to the same category,
While the service is being executed, the search means periodically searches for another service element belonging to the same category as the service element currently used for the service, and the profile description of the searched service element is stored in the service element profile description holding means. A service element search step to store;
The scoring means is a function of the user context information representing the user's situation and preferences and the profile information of the service element, and the scoring function for the corresponding category of each single evaluation criterion multiplied by the weight of the single evaluation criterion. all the values obtained by adding the single evaluation criterion, when the service element profile periodically scored for the service elements stored in the description storing means, current service element is selected, the service Service elements that were scored lower than the element, or service elements that were not found, are scored higher than the currently selected service element when they are scored higher than the currently selected service element. A scoring step to notify the execution control means as a good service element ;
When the execution control means receives the notification, it takes over the state of the currently executing service element, calls the operation of the selected better service element, and selects the currently used service element as the selected better service. Execution control steps to switch to elements;
A service element switching method. One or more service categories, each service category including one or more service elements, and at least some of the service elements during execution of a service combining one service element selected from each category; A service element switching program for causing a computer to switch to another service element belonging to the same category,
During service execution, a service element that periodically searches for other service elements belonging to the same category as the service element currently used for the service, and stores the profile description of the searched service element in the service element profile description holding means Search procedure and
All single evaluations obtained by multiplying the scoring function for each category of each single evaluation criterion by the weight of the single evaluation criterion, which is a function of the user context information indicating the user's situation and preferences and the profile information of the service element The value added for the reference is periodically scored for the service element stored in the service element profile description holding means, and when the current service element is selected, the score is lower than the service element. Service elements that were or have not been discovered will be executed as the selected better service elements if they are scored higher than the currently selected service element. A scoring procedure to notify the control means ;
When the execution control means receives the notification, it takes over the state of the currently executing service element, calls the operation of the selected better service element, and selects the currently used service element as the selected better service. An execution control procedure to switch to an element ;
Service element switching program that causes a computer to execute

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