• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1028-1033
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• 2004

The heat and flow characteristics in a single-phase parallel-flow heat exchanger was examined numerically to obtain its optimal shape. A response surface method was introduced to predict its performance approximately with respect to design parameters over design domain. Design parameters are inflow and outflow angle of the working fluid and horizontal and vertical location of inlet and outlet. The evaluation of the relative priority of the design parameters was performed to choose three important parameters in order to use a response surface method. A JF factor was used as an evaluation characteristic value to consider the heat transfer and the pressure drop simultaneously. The JF factor of the optimum model, compared to that of the base model, was increased by about 5.3%.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.115-115
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• 2014

First, We will briefly introduce early science results of AGN observations with KVN and KaVA. KaVA is the combined array of the Korean VLBI network (KVN) and VLBI Exploration of Radio Astronomy (VERA). These include KaVA monitoring of M87, Sgr A* and a few bright blazars and KVN Search for circular polarized Blazars. Furthermore, we will present our future plan of monitoring observation of Sgr A* and M87 with KaVA and Low Radio Power AGN multi frequency polarization survey with KVN. Because of the largeness of their centralsuper-massive black holes, we select them as top-priority sources of our key science program (KSP). The main science goals of the KaVA KSP are (1) mapping the velocity field of the M87 jet and testing magnetically-driven-jet paradigm, and (2) obtaining tightest constraints on physical properties of radio emitting region in Sgr A. High sensitivity achieved through simultaneous multifrequency phase referencing technique of KVN will allow us to explore Low Radio Power AGN cores which build majority of AGNs and therefore are important for undestanding the evolution of AGNs and of their hosts.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.5
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• pp.1495-1502
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• 1991

본 연구에서는 동일 작업 공간내에서 두대의 로봇이 각각의 토크의 제한 조건 과 충돌 회피 조건을 만족하면서 근사 최소 시간에 지정된 경로를 주행하기 위한 궤적 계획법을 제안하고자 한다. 이때, 동작 우선도에 의하여 한 대의 로봇은 주 로봇, 다른 한 대의 로봇은 종 로봇으로 지정되는데 주 로봇은 입력 토크의 제한조건을 만족 하며 주어진 경로를 최소 시간에 움직이도록 궤적 계획을 하였으며, 종 로봇은 주 로 봇과의 충돌을 피하고 입력 토크의 제한 조건을 만족하며 주어진 경로를 근사 최소 시 간에 움직이도록 하였다.

• Journal of Technology Innovation
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• v.5 no.1
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• pp.266-287
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• 1997

The purpose of this paper is to purpose methods and procedures by which we can set up technology planning scheme essential for R'||'&'||'D(or technology) planning in public sector (governmental and government-sponsored institutions), and can develop and select "main R'||'&'||'D projects" which are crucial to R'||'&'||'D planning, were quite specifically discussed in case of I'||'&'||'T(Information '||'&'||' Telecommunications) sector, so that they may not remain theoretical but may be practically applicable to real R'||'&'||'D programs. In this paper, the concept of technology planning was defined as a procedure for establishing nominal planning to acquire technologies efficiently for a specific sector. More detailed definition optimal technology-acquisition strategy, i.e., analyzing technological development '||'&'||' environ-ment, establishing R'||'&'||'D objectives as promising technology opportunities, selecting main R'||'&'||'D projects, allocating resources and so on."The"main R'||'&'||'D projects by technology sectors and by planning phases and then deciding on priority. Scoring method was rsed in assessment phase. Summing up, this paper suggested technology planning scheme of methods and procedures for sorting out required technologies, developing and assessing public R'||'&'||'D projects, and finally selecting main R'||'&'||'D projects.

• Broadcasting and Media Magazine
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• v.11 no.1
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• pp.78-85
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• 2006

Cognitive radio is a paradigm for wireless communication in which either network of wireless node itself changes particular transmission or reception parameters to execute its tasks efficiently without interfering with the licensed users. This paper represents a performance of the cognitive radio technology on dual polarized MIMO system using six-port receiver. Six-port technology is well known direct conversion receiver. In this paper, a six-port phase discriminator based polarization signal separation is shown. That is, the SER(Symbol Error Rate) performance is improved using polarization separator and simple receiver architecture is proposed applying six-port receiver. The six-port technology has priority to adapt changeable frequency system and variable environments for cognitive radio. In general, dual polarized MIMO system has good capacity and quality using polarization separator [1].

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05c
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• pp.1563-1566
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• 2003

본 논문은 실시간 데이터베이스 환경에서의 동시성제어 프로토콜을 제안 그 성능을 향상시키고자 한다. 기존에 실시간 데이터베이스에서 주로 쓰이는 2PL-HP(2 Phase Locking with High Priority)의 방법은 높은 우선순위를 갖는 트랜잭션(HPT)의 선행 처리를 항상 보장하기 때문에 낮은 우선순위를 갖는 트랜잭션(LPT)의 철회 및 블로킹이 불가피하였다. 이러한 문제를 해결하고자 본 논문에서는 실시간 데이터베이스에 기존의 XAL의 기부연산을 확장하고 우선순위 개념을 도입해 LPT의 불필요한 철회 및 기다림을 방지할 수 있는 효율적인 동시성제어 프로토콜을 제안한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.105-106
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• 2015

As the Long-life certification system is recently introduced in the Housing Law in Korea, it is expected that an application of the lightweight wall panel will be increased in apartment construction as the main wall system. However, the performance criteria for lightweight wall is in the early phase of its action. Therefore, it is necessary to establish the performance criteria properly by investigating performance requirement in the user's perspective. The purpose of this study is to identify of the weight of the required performance items for the lightweight wall in apartment house. To analyze the priority in the performance, an interview survey is performed; after monitering the test-bed of the lightweight walls, user and experts evaluate the performance requirements. The weight of the performance requirement is developed by AHP method.

• Journal of the Korean Institute of Educational Facilities
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• v.12 no.6
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• pp.5-17
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• 2005

The purpose of the study is to propose architectural design standards of the Multi-purpose Auditorium planning in educational facilities. The success of the design is measured by how well variable elements are applied to parts of Multi-purpose Auditorium and designed and equipped so that all groups-amateurs, professionals, youth, and adult alike-may use it effectively. The use of this facility will extend over a wide range, including concerts, plays, motion pictures, forums, and other forms of presentation. The wall, stage, roof, windows, and furnitures are important parts of Multi-purpose Auditorium and variable elements can applied to these parts. To successfully application of variable elements, it is necessary that these elements are considered in planning phase including time schedule planning. Various elements are permit a more informal and flexible arrangement and extensive learning activity.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1553-1558
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• 2009

Give high priority to the technologies that can be directly applicable to the U-City development projects which are in progress by many central and local governments. Create a real world product at the end of R&D phase by testing prototypes in test-beds or test-labs. Recently, new construction technologies have been developed, but they are rarely being applied to the construction filed. In this paper, the basic design was examined so that various technologies can be selected through a test-bed, analyzed for the real situation, and applied to actual construction sites. Improve productivity of regional and urban construction exercises and improve competitiveness of related products and services using IT-based telemetering/GIS technology.

• Korean Journal of Construction Engineering and Management
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• v.11 no.3
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• pp.55-63
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• 2010

Although the environmental conflicts regarding noise and vibration are continually increasing during construction, noise and vibration occurring in construction are only managed in construction phase. Noise and Vibration occurring in construction are considered to be insufficient, so we find that noise and vibration management in design phase has to be operated for reducing. The objective of this paper is to present noise and vibration management lists to consider in design phase for enhancing efficiency in noise and vibration management and to develop the appraisal sheets for designers to evaluate and the manuals to easily use management lists. To achieve this, we identify the noise and vibration management lists to consider in design phase through analyzing the previous literatures and confirm the 9 lists through conducting a research with experts in environmental area for verifying the propriety of lists. Also, this study applies to AHP technique to identify the priority and the weight evaluation among the lists. Through this study, we identify the most efficient lists, including from the low noise and low vibration methods, the noise and vibration reduction by blasting works, the installment and the arrangement of noise and vibration control equipments, for noise and vibration management in design phase. The achievement of this study will help to prevent the environmental disputes and conflicts in advance and will consider utilizing for the successful construction project.