• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.1
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• pp.175-182
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• 2011

In this paper, we implemented a high-performence memory controller which can accommodate processing blocks(multiple masters) in SoC for video signal processing. The memory controller is arbitrated by the internal arbiter which receives request signals from masters and sends grant and data signals to masters. The designed memory controller consists of Master Selector, Mster Arbiter, Memory Signal Generator, Command Decoder, and memory Signal Generator. It was designed using VHDL, and verified using the memory model of SAMSING Inc. For FPGA synthesis and verification, Quartus II of ATERA Inc. was used. The target device is Cyclone II. For simulation, ModelSim of Cadence Inc was used. Since the designed H/W can be stably operated in 174.28MHz, it satisfies the specification of SDRAM technology.

• The Journal of Information Technology
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• v.4 no.3
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• pp.139-154
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• 2001

In current role-based systems, security officers handle assignments of users to roles. This may increase management efforts in a distributed environment because of the continuous involvement from security officers. The technology of role-based delegation provides a means for implementing RBAC in a distributed environment with empowerment of individual users. The basic idea behind a role-based delegation is that users themselves may delegate role authorities to other users to carry out some functions on behalf of the former. This paper presents a rule-based framework for user-level delegation model in which a user can delegate role authority by creating new delegation roles. Also, a rule-based language for specifying and enforcing the policies is introduced.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.1
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• pp.104-115
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• 2010

Development of the system which provides services using diverse sensors is expanding due to the widespread use of ubiquitous technology, and the research on the security technologies gaining attention to solve the vulnerability of ubiquitous environment's security. However, there are many instances in which flexible security services should be considered instead of strong only security function depending on the context. This paper used Fuzzy algorithm and MAUT to be aware of the diverse contexts and to propose context-aware security service which provides flexible security function according to the context.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.292-297
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• 2008

복잡한 시맨틱을 포함한 웹 문서를 정확히 범주화하고 이 과정을 자동화하기 위해서는 인간의 지식체계를 수용할 수 있는 표준화, 지능화, 자동화된 문서표현 및 분류기술이 필요하다. 이를 위해 키워드 빈도수, 문서내 키워드들의 관련성, 시소러스의 활용, 확률기법 적용 등에 사용자의도(intention) 정보를 활용한 범주화와 조정 프로세스를 도입하였다. 웹 문서 분류과정에서 시소러스 등을 사용하는 지식베이스 문서분류와 비 감독 학습을 하는 사전 지식체계(a priori)가 없는 유사성 문서분류 방법에 의도정보를 사용할 수 있도록 기반체계를 설계하였고 다시 이 두 방법의 차이는 Hybrid조정프로세스에서 조정하였다. 본 연구에서 설계된 HDCI(Hybrid Document Classification with Intention) 모델은 위의 웹 문서 분류과정과 이를 제어 및 보조하는 사용자 의도 분석과정으로 구성되어 있다. 의도분석과정에 키워드와 함께 제공된 사용자 의도는 도메인 지식(domain Knowledge)을 이용하여 의도간 계층트리(intention hierarchy tree)를 구성하고 이는 문서 분류시 제약(constraint) 또는 가이드의 역할로 사용자 의도 프로파일(profile) 또는 문서 특성 대표 키워드를 추출하게 된다. HDCI는 문서간 유사성에 근거한 상향식(bottom-up)의 확률적인 접근에서 통제 및 안내의 역할을 수행하고 지식베이스(시소러스) 접근 방식에서 다양성에 한계가 있는 키워들 간 관계설정의 정확도를 높인다.

• Journal of Information Technology Services
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• v.5 no.3
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• pp.173-186
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• 2006

The local public organizations, to secure the Confidentiality, Integrity, Authentication and Non-Repudiation of cyber administrative environment is giving it a try to consolidate the official documents among them by standardizing all the documents into XML formats together with the establishment of the GPKI(Government Public Key Infrastructure). The Authentication System based on the PKI(Public Key Infrastructure) used by the GPKI, however, provides only the simple User Authentication and thus it results in the difficulty in managing the position, task, role information of various users required under the applied task environment of public organizations. It also has a limitation of not supporting the detailed access control with respect to the XML-based public documents.In order to solve these issues, this study has analyzed the security problems of Authentication and access control system used by the public organizations and has drawn the means of troubleshoot based on the analysis results through the scenario and most importantly it suggests the access control model applied with PMI and SAML and XACML to solve the located problem.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.4
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• pp.11-26
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• 2011

The existing anonymous authentication schemes based on group signatures for protecting privacy do not provide anonymous authorization which is required in the practical environments. In this paper, we propose an anonymous authentication and authorization scheme that enables a service provider both to authenticate anonymously its users and to provide different service according to their authorization. In the proposed scheme, a user's real identity, anonymity and authorization are managed distinctly through the separation of group manager's capabilities and an authorization authority. It is also possible for the proposed scheme to apply various access control models.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.1020-1023
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• 2010

소프트웨어 개발은 복잡도가 높고 가시성 확보가 어려워 전략적으로 접근해야 한다. 일반 개발 프로젝트에서 개발 전략은 특정 개발 모델과 프로젝트 관리 기법을 사용하겠다는 것이 주류를 이루고 있다. 이러한 방법은 각 개발 단계에서 업무를 진행하는 프로젝트 참여자가 프로젝트 전체를 보지 못하고 각자의 전문 분야만을 국지적으로 개발하여 초기에 의도된 대로 개발되지 않는 결과를 초래하는 경우가 다반사여서 개발 전략으로서의 역할을 적절히 수행하지 못하는 문제가 있다. 본 연구에서는 리스크 기반의 개발 전략을 제시한다. 개발 프로젝트 전체는 물론 개발의 각 단계 별로 전략이 존재할 수 있으며, 전사 차원과 프로젝트 차원의 전략이 존재한다. 분석한 리스크 레벨에 차등적으로 개발 리소스를 할당하고, 개발 기법을 사용하고, 리뷰 및 검증 활동을 진행하여 제한된 개발 리소스를 합리적이고 적절하게 사용하여 개발하고, 개발 과정을 모니터링 및 제어하는 접근법이다. 이미 개발의 일부인 테스팅 분야에서는 리스크 기반 테스팅 전략이라는 이름으로 활용하여 직간접적인 효과를 보고 있으며, 같은 개념을 개발 전체로 확장하여 개발 전략으로 체계화하여 제시한다.

• Journal of Korea Multimedia Society
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• v.8 no.9
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• pp.1258-1268
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• 2005

While the concept of Home Network is laying by and its interests are increasing by means of digitalizing of the information communication infrastructure, many efforts are in progress toward convenient lives. Moreover, as information household appliances which have a junction of connecting to the network are appearing over the past a few years, the demands against intellectual Home Services are increasing. In this paper, by being based upon Multimedia which is an essential factor for developing of various application services on ubiquitous computing environments, we suggest a simplified application model that could apply the information to the automated processing system after studying user's behavior patterns using authentication and access control for identity certification of users. In addition, we compared captured video images in the fixed range by pixel unit through some time and checked disorder of them. And that made safe of user certification as adopting self-developed certification method which was used 'Hash' algorism through salt function of 12 byte. In order to show the usefulness of this proposed model, we did some testing by emulator for control of information after construction for Intellectual Multimedia Server, which ubiquitous network is available on as a scheme so as to check out developed applications. According to experimental results, it is very reasonable to believe that we could extend various multimedia applications in our daily lives.

• Journal of Korean Society of Transportation
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• v.23 no.4 s.82
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• pp.57-69
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• 2005

The goal of this paper is to develop freeway Origin-Destination (OD) demand estimation model using real-time traffic data collected from Freeway Traffic Management System (FTMS). In existing research, the micro-simulation models had been used to get a link distribution proportion by time process. Because of hi-level problem between the traffic flow model and the optimal OD solution algorithm, it is difficult for the existing models to be loaded at FTMS. The formulation of methodology proposed in this paper includes traffic flow technique to be able to remove the bi-level problem and optimal solution algorithm using a genetic algorithm. The proposed methodology is evaluated by using the real-time data of SOHAEAN freeway, South Korea.

• Explosives and Blasting
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• v.34 no.4
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• pp.10-18
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• 2016

Explosive blasting utilizes the energy produced from the explosion of explosive materials. Since the black powder, the first type of explosive, was invented, various types of explosives have been developed until a recent emulsion explosive which is powerful as well as safe in use. The detonators continue to be developed from safety fuse to the recent electronic detonators which allow extremely accurate and flexible control of delay time. However, the good explosives and detonators do not always lead to the good blast results. It entirely depends on the blast engineer. It is necessary to develop the empirical or theoretical models based on the field experience and sound theoretical algorithm. Such models would be very useful for blast design and, furthermore, provide the idea of further technical development. This paper introduces some models used in explosive blasting and attention to be paid for field application.