• Title/Summary/Keyword: Context

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Differences in priorities of high school students' knowledge activated in laboratory and earth environmental contexts (고등학교 학생들의 문제해결에서 맥락에 따라 활성화되는 지식의 우선순위차이)

  • Lee, Myoeng-Jee
    • Journal of The Korean Association For Science Education
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    • v.14 no.3
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    • pp.304-311
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    • 1994
  • Four science concepts were selected from high school science textbook to investigate the differences in priorities of students knowledge activated during solving earth science problems in laboratory and earth science environmental contexts. Two items, one for laboratory context and the other for earth environmental context, were developed for earth selected concept The subjects were constituted of 192 students in 11th grade and 196 in 12th grade in one senior high school. Students' responses were categorized using graph models and analyzed in terms of 'Common Activated Knowledge'(CAK). and 'Specific Activated Knowledge'(SAK) across students' cognitive frames, grades, and sex. As contextual differences of the problems increased, context effects in priorities of CAK were reported in favor of laboratory context, on the contrary those of SAK in favor of earth environmental context. Context effects were reported across cognitive frames, especially students with laboratory cognitive frames showed more significant context effects than others. Lower graders and girls showed relatively large context effects. The results of this study showed that science concepts learned in a laboratory context are not easily transferred to earth environmental context. Therefore, special instructional strategies should be developed to overcome the context effect s according to activated knowledges with high priorities in laboratory and earth environmental context.

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Context Driven Component Model Supporting Scalability of Context (상황정보의 확장성을 지원하는 상황정보 기반 컴포넌트 모델)

  • Yoon, Hoi-Jin;Choi, Byoung-Ju
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.1
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    • pp.24-34
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    • 2007
  • Since Context Driven Component model is based on the idea that a context-aware application consists of the components that are context sensitive and the components that do not depend on the context, it divides the context sensitive part into components according to which context information they are related to. The model supports the scalability of context information by building an application through composing Context Driven Components. Furthermore, it solves the embeddedness of context information inside the application logic. To show the contributions of the model, this paper applies it to Call-forwarding application, and analyses how the model supports the scalability and the embeddedness.

A Context Model Comparison Methodology for Developing Generic Context Model used in Ubiquitous Multi-Services (유비쿼터스 멀티 서비스 개발에서의 일반적 상황모형 구축을 위한 상황모형 비교 평가방법론)

  • Park, Tae-Hwan;Kwon, Oh-Hyung
    • Journal of Intelligence and Information Systems
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    • v.13 no.1
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    • pp.29-47
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    • 2007
  • Acquiring context data in a timely and correct way is now regarded as one of the crucial characteristics of the proactive service which runs on ubiquitous computing environment. Moreover, context model should be well designed to provide a solid context-aware system. Since the ubiquitous computing systems aim to provide context-aware services everywhere with any available devices, legacy services which uses context models assuming single or limited domain should be extended enough to be useful even for multi-domain muli-services. This leads us to a motivation to build a generic context model with an appropriate type of model. Hence, the purpose of this paper is to propose a generic context model by assessing a variety of model types with a sort of evaluation measures.

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A Context-based Multi-Agent System for Enacting Virtual Enterprises (가상기업 지원을 위한 컨텍스트 기반 멀티에이전트 시스템)

  • Lee, Kyung-Huy;Kim, Duk-Hyun
    • The Journal of Society for e-Business Studies
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    • v.12 no.3
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    • pp.1-17
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    • 2007
  • A virtual enterprise (VE) can be mapped into a multi-agent system (MAS) that consists of various agents with specific role(s), communicating with each other to accomplish common goal(s). However, a MAS for enacting VE requires more advanced mechanism such as context that can guarantee autonomy and dynamism of VE members considering heterogeneity and complex structure of them. This paper is to suggest a context-based MAS as a platform for constructing and managing virtual enterprises. In the Context-based MAS a VE is a collection of Actor, Interaction (among Actors), Actor Context, and Interaction Context. It can raise the speed and correctness of decision-making and operation of VE enactment using context, i.e., information about the situation (e.g., goal, role, task, time, location, media) of Actors and Interactions, as well as simple data of their properties. The Context-based MAS for VE we proposed('VECoM') may consists of Context Ontology, Context Model, Context Analyzer, and Context Reasoner. The suggested approach and system is validated through an example where a VE tries to find a partner that could join co-development of new technology.

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SOFT DECISION CONTEXTS BASED ON SOFT CONTEXTS

  • Won Keun, Min
    • Honam Mathematical Journal
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    • v.44 no.4
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    • pp.628-635
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    • 2022
  • For another study of soft context and soft concept closely related to formal context and formal concept, in this paper, we propose the notions of conditional concepts, decision concepts and soft decision context based on soft contexts. Subsequently, the notions of consistent soft decision context and consistent set are introduced, and some properties for consistent set of soft decision contexts are investigated.

Context Prediction Using Right and Wrong Patterns to Improve Sequential Matching Performance for More Accurate Dynamic Context-Aware Recommendation (보다 정확한 동적 상황인식 추천을 위해 정확 및 오류 패턴을 활용하여 순차적 매칭 성능이 개선된 상황 예측 방법)

  • Kwon, Oh-Byung
    • Asia pacific journal of information systems
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    • v.19 no.3
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    • pp.51-67
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    • 2009
  • Developing an agile recommender system for nomadic users has been regarded as a promising application in mobile and ubiquitous settings. To increase the quality of personalized recommendation in terms of accuracy and elapsed time, estimating future context of the user in a correct way is highly crucial. Traditionally, time series analysis and Makovian process have been adopted for such forecasting. However, these methods are not adequate in predicting context data, only because most of context data are represented as nominal scale. To resolve these limitations, the alignment-prediction algorithm has been suggested for context prediction, especially for future context from the low-level context. Recently, an ontological approach has been proposed for guided context prediction without context history. However, due to variety of context information, acquiring sufficient context prediction knowledge a priori is not easy in most of service domains. Hence, the purpose of this paper is to propose a novel context prediction methodology, which does not require a priori knowledge, and to increase accuracy and decrease elapsed time for service response. To do so, we have newly developed pattern-based context prediction approach. First of ail, a set of individual rules is derived from each context attribute using context history. Then a pattern consisted of results from reasoning individual rules, is developed for pattern learning. If at least one context property matches, say R, then regard the pattern as right. If the pattern is new, add right pattern, set the value of mismatched properties = 0, freq = 1 and w(R, 1). Otherwise, increase the frequency of the matched right pattern by 1 and then set w(R,freq). After finishing training, if the frequency is greater than a threshold value, then save the right pattern in knowledge base. On the other hand, if at least one context property matches, say W, then regard the pattern as wrong. If the pattern is new, modify the result into wrong answer, add right pattern, and set frequency to 1 and w(W, 1). Or, increase the matched wrong pattern's frequency by 1 and then set w(W, freq). After finishing training, if the frequency value is greater than a threshold level, then save the wrong pattern on the knowledge basis. Then, context prediction is performed with combinatorial rules as follows: first, identify current context. Second, find matched patterns from right patterns. If there is no pattern matched, then find a matching pattern from wrong patterns. If a matching pattern is not found, then choose one context property whose predictability is higher than that of any other properties. To show the feasibility of the methodology proposed in this paper, we collected actual context history from the travelers who had visited the largest amusement park in Korea. As a result, 400 context records were collected in 2009. Then we randomly selected 70% of the records as training data. The rest were selected as testing data. To examine the performance of the methodology, prediction accuracy and elapsed time were chosen as measures. We compared the performance with case-based reasoning and voting methods. Through a simulation test, we conclude that our methodology is clearly better than CBR and voting methods in terms of accuracy and elapsed time. This shows that the methodology is relatively valid and scalable. As a second round of the experiment, we compared a full model to a partial model. A full model indicates that right and wrong patterns are used for reasoning the future context. On the other hand, a partial model means that the reasoning is performed only with right patterns, which is generally adopted in the legacy alignment-prediction method. It turned out that a full model is better than a partial model in terms of the accuracy while partial model is better when considering elapsed time. As a last experiment, we took into our consideration potential privacy problems that might arise among the users. To mediate such concern, we excluded such context properties as date of tour and user profiles such as gender and age. The outcome shows that preserving privacy is endurable. Contributions of this paper are as follows: First, academically, we have improved sequential matching methods to predict accuracy and service time by considering individual rules of each context property and learning from wrong patterns. Second, the proposed method is found to be quite effective for privacy preserving applications, which are frequently required by B2C context-aware services; the privacy preserving system applying the proposed method successfully can also decrease elapsed time. Hence, the method is very practical in establishing privacy preserving context-aware services. Our future research issues taking into account some limitations in this paper can be summarized as follows. First, user acceptance or usability will be tested with actual users in order to prove the value of the prototype system. Second, we will apply the proposed method to more general application domains as this paper focused on tourism in amusement park.

Design and Implementation of Pattern Collection Model for Handling the Context on a Ubiquitous Environment (유비쿼터스 환경에서 Context 처리를 위한 패턴 수집 모델의 설계와 구현)

  • Lee, Dae-Jun;Kim, Sung-Jo
    • Proceedings of the Korean Information Science Society Conference
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    • 2007.06d
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    • pp.344-349
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    • 2007
  • 유비쿼터스 환경에서 사용자의 편의성을 증대하기 위해 상황인지 기술이 필요하며 댁내의 다양한 기기의 정보를 수집하여 현재 상태를 파악하고 그에 맞는 서비스를 제공해야 한다. 하지만 다양한 종류의 디바이스, 센서, 서비스에 따라 생성하는 데이터의 형태와 의미가 다르기 때문에 이를 활용하는데 어려움이 있다. 본 논문은 다양한 기기와 환경에서 발생하는 데이터를 처리하여 사용자의 패턴을 수집하고 활용할 수 있는 연구 모델을 제안하고 구현한다. 구성요소는 실제 환경과 유사하게 Context를 생성할 수 있는 Emulator와 수집된 Context를 활용하여 패턴을 찾는 패턴 수집 서버와 수집된 데이터를 표현하는 시각화 도구로 구성된다. Emulator는 댁내에 존재할 수 있는 다양한 종류의 Context를 정의하고 서로간의 관계에 따라 Context를 생성하고 패턴 수집 서버는 Emulator에서 생성한 불완전한 Context를 통합하여 완전한 Context를 생성한다. 그리고 생성된 Context를 통해서 사용자의 서비스 이용패턴, Fault, Conflict를 발견했다.

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A Development of Intelligent Context-Awareness Middleware (지능적 상황인지 미들웨어의 개발)

  • Suh, Joohee;Woo, Chong-Woo
    • Journal of Information Technology Services
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    • v.11 no.sup
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    • pp.165-176
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    • 2012
  • Context-Awareness system provides an appropriate service to user by recognizing situation from surrounding environment. There are many successful studies on this framework, but still has some limitations. In this paper, we are describing a context-awareness middleware that can enhance the limitation of the previous approaches. We first defined a new concept of context-awareness environment as a social intelligence. This concept implies that intelligent objects can make relationships, can aware of situation from surrounding environment, and can collaborate to accomplish a given task. The significance of the study is as follows. First, the system is capable of multi context-awareness since it is designed with a structure that supports multiple lines of reasoning. Second, the system is capable of context planning by adapting AI planning mechanism. Third, the system is capable of making the intelligent objects as a group for collaboration, and provides adaptive service to user. We have developed a prototype of the system and tested with a virtual scenario.

A Jini-based context-aware chatting program (jini 기반의 context-aware chatting program)

  • Park, Han-Sol;Choi, Tae-Uk;Chung, Ki-Dong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.11b
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    • pp.1177-1180
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    • 2003
  • 차세대 비젼 컴퓨팅 환경인 유비쿼터스 컴퓨팅(Ubiquitous Computing)환경에서는 사용자에 대한 상황(context)변화에 적응적(adaptive)으로 서비스 해줄 수 있는 응용이 필수적인 요소라고 할 수 있다. Service기반의 분산 네트워크인 JINI를 기반으로, 사용자에 대한 상황을 인식(context-aware)하기 위한 시스템 연구 역시 관심의 대상이라고 한 수 있겠다. 본 논문에서는 이러한 환경을 기반으로 사용자에 대한 행동, 감정상태, 위치와 같은 정보를 인식할 수 있으며, 검색을 통해 사용자의 위치정보, 활동형태 등의 context들을 질의 할 수 있는 Context-aware 챗팅 프로그램을 기술하고 있다. 또한 인터페이스를 사용하는 사용자들에 대한 context 데이터의 표현과 질의를 위해 메타언어인 eXtensible Makup Language (XML)을 사용하였다. 이러한 context-aware system은 편재형 컴퓨팅환경 하에서 사용자에게 유효한 context를 생성 및 관리, 응용 서비스에서 유용하게 이용할 수 있을 것이다.

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A Recommendation System using Dynamic Profiles and Relative Quantification

  • Lee, Se-Il;Lee, Sang-Yong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.7 no.3
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    • pp.165-170
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    • 2007
  • Recommendation systems provide users with proper services using context information being input from many sensors occasionally under ubiquitous computing environment. But in case there isn't sufficient context information for service recommendation in spite of much context information, there can be problems of resulting in inexact result. In addition, in the quantification step to use context information, there are problems of classifying context information inexactly because of using an absolute classification course. In this paper, we solved the problem of lack of necessary context information for service recommendation by using dynamic profile information. We also improved the problem of absolute classification by using a relative classification of context information in quantification step. As the result of experiments, expectation preference degree was improved by 7.5% as compared with collaborative filtering methods using an absolute quantification method where context information of P2P mobile agent is used.