• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.10
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• pp.901-907
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• 2000

The conceptual determination of mixed-refrigerant (MR) for a closed Joule-Thomson cryocooler is described in this paper. The thermodynamic cycle design was mainly considered to develop a cryocooler by using a compressor of domestic air-conditioning unit. The target cooling performance of the designed cryocooler is 10 W around 70 K with less than 5 kJ/kg enthalpy rise. The systematic approach of choosing a proper refrigerant among 20 different kinds of mixture for such cryogenic temperature was introduced in detail. The main components of the cryocooler are compressor, evaporator, oil separator, after-cooler, counterflow heat exchanger, and J-T expansion device. Due to the limitation of the compressor operation range, the temperature after the compression was limited below $117^{\circ}C$ (390 K) and the temperature before compression was restricted above $5^{\circ}C$ (278 K). 20 atm of discharging pressure (high pressure) and less than 3 atm suction pressure (low pressure) were the design conditions. The inlet temperature of a counterflow heat exchanger in the high Pressure side was about 300 K. The proper composition of the mixed refrigerant for the designed J-T cryocooler is 15% mol of$ N_2, 30% mol of $CH_4,\; 30% mol\; of C^2H^ 6,\; 10%\; mol\; of\; C_3H_8\; and \;15%\; mol\; of\; i-C_4H_10$.

• Journal of Information Technology Applications and Management
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• v.20 no.2
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• pp.69-87
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• 2013

The expanded spiral model in this paper consists of five processes of architecture design, architectural construction, architectural maintenance, operation, and architectural management. The former four processes are executed alternatively, while the latter architectural management process is executed continuously interacting with the other processes during the whole life cycle of the system. The expanded spiral model provides a conceptual framework to sort discussions of architectural degeneration into those of product-oriented processes and those of management processes, making it possible to incorporate the models and body of knowledge about project and program management especially those of Project Management Institute, into discussions of architectural degeneration. A good architecture decomposes the software-intensive system into components mutually interacting in a well-formed structure. The architecture design process and the architectural construction process together create the object system with well-designed architecture. The architectural maintenance process prevents the implemented architecture deviate from the designed architecture. The architectural management process monitors the changes of requirements including architecturally significant requirements, supports the other processes to be executed reflecting various perspectives of stake-holders, and creates and documents the reasons of architectural decisions, which is considered as a key element of the architecture.

• Korean Business Review
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• v.13
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• pp.31-47
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• 2000

Trust has been viewed from many perspectives according to their domains. This article reviewed some of many formerly suggested studies and models. And antecedents of trust, such as trustworthiness(ability, benevolence, integrity) and individual trust propensity as well as their interactions, were respectively and empirically tested in the context of Korean workplaces. Through the factor analysis of field survey(N=243), proposed conceptual independence in trustworthiness was only partially supported. Of the relationships between antecedents and trust, all components of trustworthiness were significantly sustained. While effects of individual trust propensity and its interactions with trustworthiness on trust were not found.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.5
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• pp.185-190
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• 2006

The security analysis relates to the ability of the electric systems to survive sudden disturbances such as electric short circuits or unanticipated loss of system elements. It is composed of both steady state and dynamic security analyses, which are not two separate issues but should be considered together. In steady state security analysis including voltage security analysis, the analysis checks that the system is operated within security limits by OPF (optimal power flow) after the transition of a new operating point. On the other hand, dynamic security analysis deals that the transition will lead to an acceptable operating condition. Transient stability, which is the ability of power systems to maintain synchronism when subjected to a large disturbance, is a principal component in dynamic security analysis. Usually any loss of synchronism will cause additional outages. They make the present steady state analysis of the post-contingency condition inadequate for unstable cases. This is the reason of the need for dynamics of systems. Probabilistic criterion can be used to recognize the probabilistic nature of system components and shows the possibility of system security. A comprehensive conceptual framework for probabilistic static and dynamic assessment is presented in this paper. The simulation results of the Western System Coordinating Council (WSCC) system compare an analytical method with Monte-Carlo simulation (MCS). Also, a case study of the extended IEEE Reliability Test System (RTS) shows the efficiency of this approach.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.4
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• pp.81-93
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• 1995

Landscape Style would take various influences in general. In that of Korean Palaces religious thinking has been caused he most important factor. This conceptual attitude has been derived from Confucian philosophies and the doctrines of Taoism, the realm of ideas that had constituted the schema of culture through long times in the Orient. This paper has dealt with the influences of one's outlook on the universe, antropocentricism, and on the relationships of man and nature in those two major teachings upon the landscape style of palaces in Chosun Dynasty. The Confucian philosophies and the doctrines of Taoism in Taosim in palaces would be summarized as followings: 1. The composition of exterior spaces had been understood as a place for moral training and political morality in the world view of Confucious. 2. The view point on court circle with plants and trees had directed to the influences of beauty upon the human spirit, and it is clear in naming attitude. 3. The composition type of void and solid in palaces would focused on the completion of Confucian thoughts totally, and the method of a unit space is same. 4. The double symbolic ideas could be find out in the components of exterior space; one is Confucian in phenomena, the other is Taoism in meaning. This can be cleared in Pangji(方池), layout of natural features, and in planting methods. As a conclusion, the common spiritual base in landscape architecture of Korean old palaces can be understood as two major thinkings; Confucian philosophies and the doctrines of Taoism.

• Journal of Information Technology Services
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• v.14 no.3
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• pp.147-161
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• 2015

The rapid changes in consumption patterns and the manufacturing industry environment are both a threat and an opportunity for small and medium-sized enterprises in Korea because it lacks innovative capacity compared to large conglomerates. In this new manufacturing environment, social manufacturing is an innovative business model that can create new business opportunities for these companies. However, there are not that many proven models of platforms where products are created jointly with consumers. Some conceptual analysis of the success factors and operation strategy of co-creation platforms have started to be released but there are almost no empirical studies conducted on this matter today. In this study, the social manufacturing platform business concept and its components were studied; various factors that affect the willingness to participate in consumer-led co-creation platforms were considered; the factors were surveyed on potential consumers; a study was carried out to analyze the relationship of these factors; a model of these factors were set up and proven.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.345-346
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• 2008

Most pedestrian-vehicle crashes involve frontal impacts, and the vehicle front structures are responsible for most pedestrian injuries. The vehicle bumper contacts the lower legs at first. The leading edge of the hood (bonnet) strikes the proximal upper leg and finally, the head and upper torso hit the top surface of the hood or windscreen. In essence, the pedestrian wraps around the front of the vehicle until pedestrian and vehicle are traveling at the same speed. Since the hood surface is made from sheet metal, it is a relatively compliant structure and does not pose a major risk for severe head trauma. However, serious head injury can occur when the head hits a region of the hood with stiff underlying structures such as engine components. The solution is to provide sufficient clearance between the hood and underlying structures for controlled deceleration of a pedestrian's head. However, considerations of aerodynamic design and styling can make it extremely difficult to alter a vehicle's front end geometry to provide more under-hood space. In this study, the safe hood will be developed by designing new conceptual inner panel in order to decrease the pedestrian's head injuries without changing hood outer geometry.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.1
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• pp.289-301
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• 2019

This paper explores community-based flood disaster risk governance by applying a sensemaking approach. The conceptual sensemaking framework consists of individual experience, dialogue, and socialization components, which together comprise an interconnected system. This study presents a method for applying this framework by using a concerns table and a SWOT analysis to examine the concerns of residents living in a flood plain. A series of community-based workshops on flood risk reduction was conducted with residents of the flood-prone Muraida community in Shiga Prefecture, Japan. During the workshops, residents' concerns regarding flood risk surfaced. This study used an idiographic approach to examine the proceedings of the workshops. SWOT issue analysis was used to examine the strengths and weaknesses in the Muraida community's internal capacities, and examine the opportunities and threats in the external capacities (e.g., local government). Additionally, a SWOT strategy analysis was conducted to identify strategies for knowledge sharing and development of cooperative countermeasures that can be undertaken between the Muraida community and the local government. The results show that the concerns table can not only summarize the main concerns of all workshops, but also provide an understanding of alternative flood risk countermeasures that can be carried out.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.30-30
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• 2017

한반도의 기후변화는 전 세계 평균보다도 빠르게 진행되고 있다. 최근 빈발하고 있는 태풍 및 극한 강우, 폭설과 한파, 온난화 현상 등이 그 예이다. 특히 북한지역은 오랜 식량난과 에너지난으로 산림생태계가 훼손되어 홍수 및 이수와 같은 기후변화 관련 자연재해에 매우 취약하다. 이렇게 예상되는 대규모 자연재해를 대비하고 기후변화에 효율적으로 대처하기 위해서는 체계적이고 과학적인 기상 및 기후 예측 정보의 활용이 매우 중요하다. 하지만 북한지역은 우리가 수문자료를 구하기가 힘들고, 직접 측정을 할 수 없으므로 수문자료의 수집에 한계가 있기 때문에 기후변화관련 수문연구에 한계점이 있다. 따라서 본 논문에서는 WMO에서 제공하고 있는 북한의 27개 기상관측소의 강수량, 기온자료와 기상청의 RCP8.5기후변화시나리오를 제공 받아 각 관측소별 미래 잠재증발산량을 산정하였다. 또한 lumped conceptual model인 WASMOD 모형을 이용하여 북한의 대표유역(금야강, 대동강, 두만강, 압록강, 예성강, 임진강, 장연남대천)에 적용하여 부족한 수문시계열자료를 산정하였다. 이렇게 산정된 북한의 미래 수문순환요소의 시계열자료를 이용하여 통계분석, 변화점분석, 유황분석등 시계열 분석 등을 통해 RCP8.5기후변화시나리오 기반의 기후변화가 북한지역의 수문순환과정에 미치는 영향을 분석하고, 이를 통해 유역규모의 수자원에 미치는 영향을 전망하였다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.4
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• pp.83-90
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• 2006

It has lately been difficult to share the research outcomes information due to the information system not being compatible with one another. To solve this problem, it is believed that a meta data standard needs to be developed for all the institutions to follow. This paper shows how to make the research outcome of Science and Technology R&D project a standard metadata. We first classified all the research outcome into the following seven groups: Report, Journal article, Presentation material, Book, Dissertation, Industrial rights, and Technology development. We then identified three components that constitute a standard metadata. We employed the Dublin Core Metadata Set and CERIF(Common European Research Information Format) for worldwide interoperability. This Standard can be applied in the following areas: 1) Developing a standard architecture to manage research result within the organization. 2) Designing a conceptual/logical database to measure and evaluate the research outcome. 3) Developing a metadata system for research outcome as a subsystem of an Industrial Technology MDR (Metadata Registry) System.