• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.7B
• /
• pp.431-437
• /
• 2007

Web proxy caching provides an effective way to reduce access latency and bandwidth requirement. In particular, prefix caching is considered as an alternative for improving video delivery over wide area networks because video objects are usually too large to be cached in their entirety. Nevertheless, many studies have pointed that the user-perceived latency is often not dominated by object transmission time, but rather by setup process such as TCP connection time that precedes it. We propose pre-connecting techniques and show that the techniques can be used efficiently in TCP splicing. Our analysis shows the pre-connection significantly reduces start-up latency and TCP connection time in simple analytical model. The deployment of the proposed pre-connection does not require protocol modification or the cooperation of other entities.

• 한국HCI학회:학술대회논문집
• /
• 2006.02b
• /
• pp.499-504
• /
• 2006

본 연구는 사회 트렌드 변화에 따른 적응 속도가 빠르고 소비 또한 타 계층에 비해서 매우 높은 지수로 구성된 20대 여성을 연구 대상으로 선정하여 이들의 다양한 감성 니즈를 파악하고 현 시점에서의 트렌드 분석을 통해 그들의 요구와 취향이 적절하게 반영된 휴대폰 GUI디자인을 대기화면을 중심으로 제시해보고자 한다. 연구방법은 사용자 감성 니즈 분석을 위해 FGI 기법을 사용하였고, 트렌드 분석을 위해서는 Town Watching과 잡지 및 웹사이트 분석을 통하여 감성형용사를 추출하였다. 추출된 형용사간의 상관치와 의미에 따라 상대축을 설정하여 공간을 설정하고 공간 위에 각 형용사와 이미지를 배열하여 감성형용사 공간을 설정하였다. 이러한 감성평가 결과에 FGI를 통해 구분한 사용자의 감성 니즈 분류를 기초로 하여 3가지의 감성테마로 분류를 하였다. 분류 기준은 사용자들이 원하는 휴대폰 이미지와 트랜드 분석을 하여 얻은 형용사를 비교하여 그룹핑하였다. 분류된 그룹에 해당하는 테마명을 지정해주었고 그에 맞는 휴대폰 GUI 디자인을 제안한다. 본 연구는 시장세분화 경향에 따라 특정 사용자 층에 대한 연구가 중요한 시점에서 20대 여성이라는 특정 사용자층에 대한 조사를 바탕으로 디자인을 이끌어내었다는데 의의가 있다.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.8 no.2
• /
• pp.26-32
• /
• 2012

The systems of the nuclear power plant are designed based on the User Requirement Document, and Korea Hydro & Nuclear Power Co. (KHNP) implements preventive maintenance activities to keep the specific design function of the system consistently. To monitor the preventive maintenance effectiveness, KHNP has also developed maintenance effectiveness monitoring (MR) program based on NUMARC 93-01 since 2003, and has implemented the program in all operating plants. Recently, KHNP has upgraded MR programs by reflecting implementing experiences ; reestablishing the performance monitoring level, improving analysis for standby function and performance criteria for passive components, reestablishing the availability performance criteria and the performance criteria for the same type of components. These upgraded MR programs will contribute to enhance safety and improve equipment reliability through monitoring maintenance effectiveness.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.4
• /
• pp.1-9
• /
• 2010

In the new generation of Web, commonly called "Web 2.0", blogging has facilitated the publishing information or his/her opinion on the web. Various blog retrieval algorithms have been proposed to search for blogs more effectively. However, actually keyword-based searching or link-analysis blog ranking system cannot satisfy the user's requirement. In this paper, we suggest a topic-based weighting blog retrieval system in which the links between blog writings and searching words are considered to improve the search results. Our system extracts topics from each blog and weights them much higher than other guide words. In the comparison with other systems, we see that the proposed topic-base system has better recall rate of search results.

• Convergence Security Journal
• /
• v.11 no.1
• /
• pp.49-56
• /
• 2011

Recently, the army make plans for the development of new conceptual military vehicles. As the development of military vehicles, we need selecting of considerable factors for solution of user's additional requirements, systematic and efficient development management of military vehicles. For this study, we made up questions from 4 specialist's groups about military vehicles as manager group, operator group, maker group, researcher group. There were 22 selected factors in the result of gathering the specialists' opinions and the result of this study will useful for hereafter development of military vehicles.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.9
• /
• pp.2982-3003
• /
• 2014

With the explosive deployment of the wireless communications technology, the increased QoS requirement has sparked keen interest in network planning and optimization. As the major players in wireless network optimization, the BS's resource utilization and mobile user's QoS can be improved a lot by the load-balancing technology. In this paper, we propose a load-balancing strategy that uses Coordinated Multiple Points (CoMP) technology among the Base Stations (BS) to effectively extend network coverage and increase edge users signal quality. To use universally, different patterns of load-balancing based on CoMP are modeled and discussed. We define two QoS metrics to be guaranteed during CoMP load balancing: call blocking rate and efficient throughput. The closed-form expressions for these two QoS metrics are derived. The load-balancing capacity and QoS performances with different CoMP patterns are evaluated and analyzed in low-dense and high-dense traffic system. The numerical results present the reasonable CoMP load balancing pattern choice with guaranteed QoS in each system.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.18 no.2
• /
• pp.139-150
• /
• 2008

Recently, financial institutes and industrial companies are adopted to security token such as OTP, smart card, and USB authentication token and so on for secure system management and user authentication. However, some research institutes have been introduced security weaknesses and problems in security tokens. Therefore, in this paper, we analyses of security functions and security requirements in security token performed by analyses of standardization documents, trends, security problems, attack methods for security tokens. Finally, we propose a CC v.3.1 based security token protection profile.

• Progress in Superconductivity and Cryogenics
• /
• v.8 no.4
• /
• pp.30-33
• /
• 2006

Several crucial issues are discussed in the design of cryogenic cooling system for high field magnets. This study is mainly motivated by our ongoing program to develop a 21 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS). The magnets of this system will be built horizontally to accomplish the requirement of user friendliness and reliability, and the replenishment of cryogen will not be necessary by a closed-loop cooling concept. The initial cool-down and safety are basically considered in this paper. The effects of the helium II volume and the gap distance of the weight load relief valve (or safety valve) on the cool-down time and temperature rising during an off-normal state are discussed. The total amount of cryogenic cooling loads and the required helium flow rate during cool-down are also estimated by a relevant heat transfer analysis. The temperatures of cryogen-free radiation shield are finally determined from the refrigeration power of a cryocooler and the total cryogenic loads.

• The Journal of Society for e-Business Studies
• /
• v.12 no.4
• /
• pp.1-15
• /
• 2007

Traceability links are logical links between individual requirements and other system elements such as architecture descriptions, source code, and test cases. These are useful for requirements change impact analysis, requirements conflict analysis, and requirements consistency checking. However, establishing and maintaining traceability links places a big burden since complex systems have especially yield an enormous number of various artifacts. We propose a feature-oriented requirements tracing method to manage requirements with cost benefit analysis, including value consideration and intermediate catalysis using features. Our approach offers two contributions to the study of requirements tracing: (1)We introduce feature modeling as intermediate catalysis to generate traceability links between user requirements and implementation artifacts. (2)We provide value consideration with cost and efforts to identify traceability links based on prioritized requirements, thus assigning a granularity level to each feature. In this paper, we especially present the results of a case study which is carried out in Apartment Ubiquitous Platform to integrate and connect home services in an apartment complex in details.

• Journal of Digital Convergence
• /
• v.10 no.7
• /
• pp.93-98
• /
• 2012

The rapid change of business environments request the company to act more smart and intelligent in making business strategies and planning the business processes. To meet this requirement, we need to have smart Business Intelligent System(hereinafter "BI") in the company. On the one hand, many korean companies had already installed BI system, and the other hand some companies have plans to implement BI Systems additionally to their Information System. It is very important to have the pictures which factors are critical to the successful implementation of BI, and to survey which critical success factor(hereinafter CSF) are important compared to each factors. In this paper data was gathered from companies already have their BI Systems. We measured IT-Infra maturity, User Education, and Company Organization, and Company Business Strategy, which are the critical success factors for the BI System. After surveying the CSF of BI System, we measured the weights among these factors by AHP. Factor analysis resulted in 6 major factors (Eigenvalue > 1.0), and the AHP analysis showed the list of CSF's weight list according to its significance priorities. The results of this paper could be the valuable references for the implementing process of the BI System in korean company.