• 품질경영학회지
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• 제39권3호
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• pp.412-421
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• 2011

In this paper, we introduce Quality of Service(QoS) analytic model of a distributed system that decentralizes the process nodes performing each task and communicates through a network for cooperation. The model advances a service reliability model of Dai et a1.(2003) by means of considering the processing time. The service is assumed to be provided by a centralized heterogeneous distributed system which is composed of some subsystems managed by a control center. The QoS is defined as the probability that a service is provided successfully in an allowed time, we consider the hardware/software reliability and the processing time which include program execution time, data transfer time. We derive the processing time distribution for a required service through convolution of corresponding probability density function. An application example is used to explain the procedure of computing quality of service.

• 한국전자거래학회지
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• 제1권1호
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• pp.69-92
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• 1996

An Integrated Data Environment (IDE) is the end state of the CALS vision. It refers to an environment where all the data generated from the entire lifecycle activities of a product can be shared by anyone that participates in the management. engineering, manufacturing, or support of the product, although the data are geographically distributed and are maintained in heterogeneous platforms. The primary purpose of this paper is to introduce the fundamental concept, architecture, and core implementation technology of an IDE. The secondary purpose is to suggest some strategic directions to the planning staffs in both government and industry. and to suggest some research issues to the researchers in academia. The reference architecture of an IDE being developed by the US DoD and that of NIIIP (National Industrial Information Infrastructure Protocol) being developed by a consortium are discussed. Two principal issues of implementing an integrated database, i.e., distributed object computing including CORBA and multi-database system (MDBS) are reviewed. As a conclusion. the author suggests that daring investment in prototyping an IDE by a nationwide consortium is essential to keep up with the advanced countries in CALS implementation.

• ETRI Journal
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• 제39권2호
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• pp.202-212
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• 2017

With the advent of the Internet-of-Things paradigm, the amount of data production has grown exponentially and the user demand for responsive consumption of data has increased significantly. Herein, we present DART, a fast and lightweight stream processing framework for the IoT environment. Because the DART framework targets a geospatially distributed environment of heterogeneous devices, the framework provides (1) an end-user tool for device registration and application authoring, (2) automatic worker node monitoring and task allocations, and (3) runtime management of user applications with fault tolerance. To maximize performance, the DART framework adopts an actor model in which applications are segmented into microtasks and assigned to an actor following a single responsibility. To prove the feasibility of the proposed framework, we implemented the DART system. We also conducted experiments to show that the system can significantly reduce computing burdens and alleviate network load by utilizing the idle resources of intermediate edge devices.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2005년도 e-Biz World Conference 2005
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• pp.62-67
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• 2005

In traditional approach, enterprise-wide consistent security policy enforcement for applications is very difficult task. Therefore, industry is now moving towards new unified enterprise application security concept that consist of centralized authentication and authorization mechanism. The eXtensible Access Control Markup Language (XACML); an XML-based standard defined by OASIS, is most suitable choice which can support centralized, role based, context aware access control mechanism. It is designed to provide universal standard for writing authorization policies and access control request/response language for managing access to the resources. This paper includes a brief overview on XACML and discusses its benefits, limitations and a data flow process. We propose a new generic access control architecture that supports enterprise wide centralized application level access control mechanism using XACML. The other benefits which can be achieved through this architecture are, reduce adnministration cost and complexity, support of heterogeneous computing platforms, centralized monitoring system, automatic fail over, scalability and availability, open standard based solution and secure communication.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.993-996
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• 1999

A mobile agent is a program which is capable of migrating autonomously from host to host in the heterogeneous network, to perform some computation on behalf of the user. Mobile agents have many advantages in the distributed computing environment. But they are likely to suffer many attacks on the security due to the mobility. In order to make use of a mobile agent in the real applications, the security issues must be addressed. We deal with the problem which is concerned with protecting a mobile agent in transit and detecting a mobile agent clone. In this paper we propose a trust center based secure mobile agent transfer protocol. This protocol transfers a mobile agent securely from host to host and detects a mobile agent clone. We further show the security of the protocol against many attacks.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권1호
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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.

• 천문학회보
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• 제43권1호
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• pp.39.2-39.2
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• 2018

GW170817/GRB170817A establishes a double neutron star merger as the progenitor of a short gamma-ray burst, starting 1.7 s post-coalescence. GRB170817A represents prompt or continuous emission from a newly formed hyper-massive neutron star or black hole. We report on a deep search for broadband extended gravitational-wave emission in spectrograms up to 700 Hz of LIGO O2 data covering this event produced by butterfly filtering comprising a bank of templates of 0.5 s. A detailed discussion is given of signal-to-noise ratios in image analysis of spectrograms and confidence levels of candidate features. This new pipeline is realized by heterogeneous computing with modern graphics processor units (GPUs). (Based on van Putten, M.H.PM., 2017, PTEP, 093F01.)

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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• pp.107-110
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• 2002

A grid computing environment is one in which applications can be built over multiple resource nodes at widespread geographic locations. Grid environments seek to integrate and enable access to widely distributed compute resources. The compute resources in a grid environment are typically heterogeneous, with varying qualify and availability Hence, how computations are allocated to individual resources is extremely important in the design of a grid. This paper j\ulcorners concerned with resource management for metacomputing. We describe a resource management architecture using the two-level resource broker.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2015년도 하계학술대회
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• pp.181-182
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• 2015

모바일 기기의 보급률과 성능이 급속도로 성장하면서 모바일 기기에서의 비디오 소비 또한 크게 증가하였다. 하지만, 전력과 공간을 줄이기 위해 설계된 모바일 플랫폼은 데스크톱 플랫폼과 비교하여 성능의 한계가 존재한다. 따라서 대용량 비디오 처리를 위해 SIMD 아키텍쳐를 이용하는 임베디드 GPU를 활용하여 이와 같은 한계를 극복하기 위한 고속화 연구가 많이 진행되고 있다. 저장된 데이터를 활용하는 영상처리는 GPU 뿐만 아니라 CPU가 반드시 함께 이용되어야 하며, 모바일 환경에서의 이기종 컴퓨팅 시스템은 프로세서 사이의 낮은 전송속도와 이로 인한 대기시간, 모바일 운영체제가 지원하는 데이터 형태의 필수적인 사용 등의 구조적 단점이 존재한다. 본 논문에서는 임베디드 GPU를 활용한 영상처리 고속화를 위해 임베디드 CPU측에서 병렬처리를 이용하여 앞서 설명한 단점들을 극복하고 실험결과로 모바일 이기종 컴퓨팅 구조에서 임베디드 CPU 활용이 전체적인 연산 효율을 증가시키는 결과를 보였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.720-723
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• 2008

RUPI 기반 로봇 서비스는 다양한 성능을 지원하는 로봇과 서버간의 연동을 통해서 융통성과 확장성을 보장하는 로봇 기반 서비스를 제공한다. 높은 H/W 성능과 계산 능력을 보장하는 Rich-Client 로봇과 달리 Thin-Client 로봇은 제한된 성능만을 제공하기 때문에, 상대적으로 높은 연산량을 요구하는 보안 알고리즘을 수행하기에는 어려움이 있다. 따라서 본 논문에서는 Thin-Client 로봇의 보안 위협과 요구사항, 및 보안 기능을 포함하는 Thin-Client 로봇 보안 프레임워크를 제안한다.