• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.1
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• pp.248-268
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• 2018

The performance of smartphone applications are usually constrained in user interactions due to resource limitation and it promises great opportunities to improve the performance by exploring the smartphone built-in and embedded sensing techniques. However, heterogeneity in techniques, semantic gap between sensor data and usable context, and complexity of contextual situations keep the techniques from seamless integration. Relevant studies mainly focus on feasibility demonstration of emerging sensing techniques, which rarely address both general architectures and comprehensive technical solutions. Based on a proposed functional model, this investigation provides a general architecture to deal with the dynamic context for context-aware automation and decision support. In order to take advantage of the built-in sensors to improve the performance of mobile applications, an ontology-based method is employed for context modelling, linguistic variables are used for heterogeneous context presentation, and semantic distance-based rule matching is employed to customise functions to the contextual situations. A case study on mobile application authentication is conducted with smartphone built-in hardware modules. The results demonstrate the feasibility of the proposed solutions and their effectiveness in improving operational efficiency.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2004.11a
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• pp.16-52
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• 2004

• Korea Information Processing Society Review
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• v.10 no.4
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• pp.182-188
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• 2003

• KIPS Transactions on Software and Data Engineering
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• v.9 no.1
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• pp.25-32
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• 2020

In the context-aware system, rule-based AI technology has been used in the abstraction process for getting context information. However, the rules are complicated by the diversification of user requirements for the service and also data usage is increased. Therefore, there are some technical limitations to maintain rule-based models and to process unstructured data. To overcome these limitations, many studies have applied machine learning techniques to Context-aware systems. In order to utilize this machine learning-based model in the context-aware system, a management process of periodically injecting training data is required. In the previous study on the machine learning based context awareness system, a series of management processes such as the generation and provision of learning data for operating several machine learning models were considered, but the method was limited to the applied system. In this paper, we propose a training data generating method of a machine learning model to extend the machine learning based context-aware system. The proposed method define the training data generating model that can reflect the requirements of the machine learning models and generate the training data for each machine learning model. In the experiment, the training data generating model is defined based on the training data generating schema of the cardiac status analysis model for older in health status notification service, and the training data is generated by applying the model defined in the real environment of the software. In addition, it shows the process of comparing the accuracy by learning the training data generated in the machine learning model, and applied to verify the validity of the generated learning data.

• Journal of the HCI Society of Korea
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• v.8 no.1
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• pp.11-17
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• 2013

Context aware systems are those systems that are aware about the environment and perform productive functions automatically by reducing human computer interactions(HCI). In this paper, we present common architecture principles of context-aware systems to explain the important aspects of context aware systems. Our study focuses on identifying common concepts in pervasive computing approaches, which allows us to devise common architecture principles that may be shared by many systems. The principles consists of context sensing, context modeling, context reasoning, context processing, communication modelling and resource discovery. Such an architecture style can support high degree of reusability among systems and allows for design flexibility, extensibility and adaptability among components that are independent of each other. We also propose a new architecture based on broker-centric middleware and using ontology reasoning mechanism together with an effective behavior based context agent that would be suitable for the design of context-aware architectures in future systems. We have evaluated the proposed architecture based on the design principles and have done an analyses on the different elements in context aware computing based on the presented system.

• Journal of Digital Contents Society
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• v.12 no.4
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• pp.437-447
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• 2011

Ubiquitous Computing is required to define models for broad context information occurrence by surrounding environment and to study how to model a mechanism for selectively collecting useful pieces of context information and providing relevant intelligent services. Further, studies are also required as to process of context information, and its maintenance and reasoning. However, current context-aware research area still lacks modeling technique that reflects the characteristics of ontology effectively for providing relevant intelligent services. It has also limitation about context reasoning and interoperability among context information. Therefore, this paper proposes ontology-based context-aware modeling technique and framework enabling efficient specification of context information for providing intelligent context-aware services that support context management and reasoning.

• 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.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.322-324
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• 2006

유비쿼터스 컴퓨팅은 사물에 컴퓨터 기능이 내장되어 언제, 어디에서나, 어느 장치로도 편리하게 주변 환경으로부터 서비스를 사용할 수 있게 하는 정보기술의 패러다임이다. 이를 위해선 상황인지가 전제되어야 하는데 여기서 상황인지라 함은 시스템의 다양한 센서 정보를 바탕으로 스스로 상황(Context)을 인지하는 것으로서, 그 정의에 있어서, 아직 논란이 많으나 지능형 서비스를 위한 중요한 개념이다. 본 논문에서는 센서로부터 바로 생성된 Raw Context 정보를 Low-Level Context라고 하고 이를 복합(Fusion)하여 이미 알려진 High-Level Context로 분류하는 논리적 연산을 추론에 기반한 상황인지로서 정의한다. 이때 센서 정보를 통해 특정한 상황정보를 추론하기 위한 모델을 설계하여 상황인지 미들웨어에 적용시켜 보고 그에 따른 효율적인 구조를 기술한다.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.6
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• pp.19-27
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• 2010

Many security issues occur in cloud computing service environment such as authentication, access control, and so on. In this paper, we propose an effective authentication and access control model which provide integrated management and control when we access various resources in cloud computing environment. To address these problems, we suggest a context-aware single sign-on and access control system using context-awareness, integrated authentication, access control, and OSGi service platform in cloud computing environment. And we show design and implementation of context-aware single sign-on and access control system. Also we verified the flexibility and convenience of the proposed system through multi fact based integrated authentication in cloud computing environment. We could provide flexible and secure seamless security service by user context in cloud computing environment.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.149-157
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• 2019

Recent research has been actively carried out on systems that want to optimize resource utilization by analyzing the intended behavior and pattern of behavior of objects (users, consumers). A service system that applies information about an object's location or behavior must include a location trigger processing system for tracking an object's real-time location. In this paper, we analyze design problems for the implementation of a context-awareness based location trigger system, and present system models based on analysis details. For this purpose, this paper introduces the concept of location trigger for intelligent location tracking techniques about moving situations of objects, and suggests a mobile agent system with active rules that can perform monitoring and appropriate actions based on sensing information and location context information, and uses them to design and implement the location trigger system for context-awareness based location services. The proposed system is verified by implementing location trigger processing scenarios and trigger service and action service protocols. In addition, through experiments on mobile agents with active rules, it is suggested that the proposed system can optimize the role and function of the application system by using rules appropriate to the service characteristics and that it is scalable and effective for location-based service systems. This paper is a preliminary study for the establishment of an optimization system for utilizing resources (equipment, power, manpower, etc.) through the active characteristics of systems such as real-time remote autonomous control and exception handling over consumption patterns and behavior changes of power users. The proposed system can be used in system configurations that induce optimization of resource utilization through intelligent warning and action based on location of objects, and can be effectively applied to the development of various location service systems.