• Journal of Energy Engineering
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• v.11 no.2
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• pp.130-135
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• 2002

Bypass air conditioning systems are divided into three types; outdoor air bypass, mixed air bypass and return air bypass system. Among bypass air conditioning systems, a return air bypass system is more effective than other two systems because it doesn't induce unconditioned outdoor air into conditioned room. The numerical study on the bypass air conditioning system shows this system can maintain indoor RH(Relative Humidity) less than a conventional CAV (Constant Air Volume) air conditioning system by adjusting face and bypass dampers at part load. A simulator was built to compare results of a numerical experiment and those of a simulator experiment. The results of the simulator experiment was nearly same as those of the numerical experiment; when a design sensible load (the ratio of sensible load to total sensible load) was 70 percent (at this time, RSHF=0.7), indoor relative humidity (in case of both numerical experiments and simulator experiments) was maintained below 60% specified by ASHRAE STANDARD 62-1999. The bypass air conditioning system is expected to be applied to many buildings where the Percentage of latent loads or air change tate is high.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.1
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• pp.82-87
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• 1987

In this study a method of shape optimization is applied to two dimensional heat transfer system. For this the optimization problem is defined in a functional form including cost, constraints and the system governing equation. Then the material derivative concept in continuum mechanics and the adjoint variable method are employed for the shape design sensitivity analysis. With the sensitivity analysis results, an optimum is sought with the gradient projection optimization algorithm. The two dimensional isoparametric finite elements are used for accurate analysis and sensitivity calculations. The above method is employed to find the boundary shape to achieve a desired temperature distribution along a segment of the boundary subject to the maximum area constraint.

• Sijohaknonchong
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• v.21
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• pp.111-141
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• 2004

Jeung Wan-yeong expresses his perception of hometown in two ways. First, it is a nature-friendly pastoral place. His geographical hometown, a nature-friendly pastoral place, is Gimcheon; he produced many works in which he longed for nature in the place. These works have a large amount of lyric, pastoral, and bucolic contents, without any conflict, on the basis of peace, longing, and Oriental nature-friendly thought. Second, the hometown perceived by Jeung Wan-yeong is a rest place for both ancestors and descendants. According to his definition, 'Hometown is a village where the living and the dead coexist: Longing for a hometown immediately may be that for parents, and is often expressed as that for siblings and old friends. In other words, a hometown is a place where there are ancestors' graves, and parents, siblings, and relatives; in Jeung Wan-yeong's works where it is perceived as a place with memories for them. the hometown has eternal maternity.

• Journal of Korean Society of Transportation
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• v.20 no.3
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• pp.7-16
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• 2002

It is very important to research drivers' visual behavior. Angle of vision is very important and accounts for more than 90% as the source of driving information. In curve sections, drivers can know the front circumstances and drive more safely and comfortably through facilities guiding their eye movements. Therefore, the standards of installation and effectiveness of these facilities to guide drivers' gaze need to be reconsidered considering characteristics of drivers' eyes The national road no. 34 (Jincheon IC, Buckamri-Yiriangmun section), which is a high-accident-frequency location, is chosen for experimental place. The aim of this study is to understand the process of drivers' visual movement which is drivers' visual behavior and to check the facilities to guide their eyes. Another goal of this study is to improve facilities to guide drivers' eyes on a result basis of considering drivers' visual behavior especially for traffic safety in a high-accident-frequency curve sections.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.1
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• pp.35-40
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• 2007

Most of eyeglasses manufacturers in Korea consist of relatively small-sized enterprises with less than 10 employees. In terms of scale, it performs considerably poor compared to other competing nations like Italy and the People's Republic of China. As a result, domestic eyeglasses industry is facing a difficult position between high-priced products of developed countries and low-priced goods of China, South East Asia, and etc. Considering these factors, the urgent solution for revitalization of domestic eyeglasses industry could be seen as major structural changes in eyeglasses producers. In addition, it is also noted that procurement of competitiveness is an essential scheme to reinvigorate the Korean eyeglasses industry. This objective can be achieved via improvement of ability to develop new designs, exploitation of new material and technology, intensification of own innovative brand and public relations, development of new products such as functional glasses, reduction of sample producing period, provision of administrative support, and designation of special economic zone.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.21-29
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• 2016

This study was conducted to review Waste Transfer Stations(WTSs) in Seoul, especially focusing on three aspects, main roles, neighbor friendly and regulation compliance, and to draw out recommendation for improvement. The 46 units of all 65 WTSs treated large amount of waste on a day shipping-out schedule, the other 19 WTSs treated small amounts of wastes which were transported after 3~30 days stock. About 57% of WTSs are located in residential or commercial area. Other 57% of WTSs were open without walls. 79% of WTSs were placed alone. Just 17% of WTSs were permitted as environmental infrastructures by urban planning law, and 31% of WTSs were operated by private waste haulers who were permitted by waste management law. Most WTSs in Seoul seemed to go well with on-going policy demand, such as regionalizing waste treatment facilities, expanding waste recycling, and so on. However lots of WTSs did not implement sufficient environmental protection measures, and partly not compliant with regulations related to urban infrastructures. In the future, the issue on sealing facilities and integrating functions of waste management facilities could be considered in order to fit in urban environment.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.318-326
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• 2020

The number of foreign qualification holders has been on the rise due to the globalization and the development of transportation. As in other developed nations, Korea faces the growing demand for foreign higher education recognition (FHER) since the number of foreign students and migrant workers has reached about one million recently. Unfortunately, there has been no FHER system in Korea so far. In this context, this study has compared the cases of Australia and New Zealand. The results reveal that these two countries are similar in that both of them have developed their own FHER system in order to attract highly qualified foreign workers and students. However, they are different in terms of the implementation of the FHER system and the development of the FHER database. Besides, the cases of both countries shed light on the key issues related to the FHER. Taken together, they provide significant implications for the Korean government which has to develop its own FHER system in the near future.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.5
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• pp.464-474
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• 2000

All-to-all personalized communication, or complete exchange, is at the heart of numerous applications, such as matrix transposition, fast Fourier Transform(FFT), and distributed table lookup.We present an efficient all-to-all personalized communication algorithm for a 2D torus inwormhole-routed networks. Our complete exchange algorithm adopts divide-and-conquer approach toreduce the number of start-up latency significantly, which is a good metric for network performancein wormhole networks. First, we divide the whole network into 2x2 basic cells, After speciallydesignated nodes called master nodes have collected messages to transmit to the rest of the basic cell,only master nodes perform complete exchange with reduced network size, N/2 x N/2. When finishedwith this complete exchange in master nodes, these nodes distribute messages to the rest of the masternode, which results in the desired complete exchange communication. After we present our algorithms,we analyze time complexities and compare our algorithms with several previous algorithms. And weshow that our algorithm is efficient by a factor of 2 in the required start-up time which means thatour algorithm is suitable for wormhole-routed networks.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.403-406
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• 2011

한국해양연구원에서는 국토해양부의 지원을 받아 2010년 7월부터 새로운 개념의 해저로봇 개발에 착수하였다. 새로이 개발되는 해저로봇은 프로펠러 방식으로 추력을 얻는 기존의 해저로봇과는 달리 여러 개의 관절로 이루어진 6개의 다리를 이용하여 해저면에 근접해서 보행과 유영으로 이동하는 해저로봇으로 강조류와 악시계의 환경에서도 운용이 가능한 로봇이다. 이 해저보행로봇 시스템은 선상시스템과 완충기, 그리고 해저보행로봇으로 구성되며, 이들 사이는 광변환기를 통해서 광케이블로 연결된다. 선상시스템에는 해저로봇의 제어 및 모니터링을 위하여 10대의 컴퓨터가 설치되어 있고, 완충기와 해저로봇에 각각 1대의 입출력 컴퓨터가 내장되어 장착된 센서와 모터의 인터페이스를 담당한다. 본 논문에서는 해저보행로봇의 통신 시스템을 소개하고, 이 통신 시스템에서 사용되기 위하여 설계된 메시지의 통신 프로토콜을 설명한다. 해저보행로봇 시스템의 주 네트워크는 기가비트 이더넷이며, 안정된 통신 환경의 소규모 독립 네트워크이다. 완충기와 해저보행로봇에는 최대 100㎐로 동작하는 다양한 직렬 통신 방식을 갖는 다수의 센서와 모터가 장착되어 있는데, 입출력 컴퓨터가 이더넷 네트워크와의 인터페이스 역할을 수행하여 계층적 네트워크를 구성한다. 로봇 제어에서는 실시간성이 중요하기 때문에 이더넷에서 통신 메시지는 한 번의 전송으로 여러 컴퓨터에 전달할 수 있도록 멀티캐스팅을 사용하여 전송된다. 설계된 통신 프로토콜은 이러한 해저로봇 시스템의 특성에 적합한 간결한 구조로 설계되었으며, 최대 255개의 주소를 지정할 수 있고 255 종류의 메시지 형태를 설정할 수 있다.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.670-678
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• 2014

This paper analyzes the characteristics of population change and makes the population projection in the mountainous area of Korea. Mountainous areas are defined as local towns (eup or myeon) with forest area more than 70 percent of land area, population density less than 111 people per square kilometer, and plowland area less than 21 percent of land area. The population in mountainous areas has decreased dramatically, while the ageing index has increased over the past two decades. To make the population projection, the cohort-change ratios method is applied. The results revealed that a multitude of young people aged 10 to 39 moved to cities to find education and job chance and some people aged 40 and over moved to mountainous areas as the trends of urban-to-rural migration. This continuing trend will culminate in 680 thousand people in population and 1,035 of ageing index in 2030, which will lead to the unequal land development and inefficient forest management. Thus, policy makers need to develop stimulus plans to revitalize and stabilize the economy of mountainous areas.