• 동력기계공학회지
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• 제11권4호
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• pp.86-91
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• 2007

This study was investigated to know the effect of subzero treatment in austempered ductile cast iron. Retained austenite transformed to martensite by subzero treatment. With decreasing subzero treatment temperature, more volume fraction of retained austenite transformed to martensite and transformed to martensite above 30% by subzero treatment temperature at $-196^{\circ}C$. With decreasing subzero treatment temperature, the value of strength and hardness increased but the value of elongation and impact value decreased. In case of subzero treatment at $-196^{\circ}C$, hardness value increased about 18% and impact value decreased by above 20%. We could find that subzero treated specimens had a little of effect on the tensile properties but had very much effect on the hardness and value of the impact.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2006년도 추계학술대회
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• pp.60-65
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• 2006

The authors map some of the current Business Models in the Massively Multiplayer Online Player scenario. These maps represent Value Creation Systems by resorting to Value Net constructs and notations, and are offered here as a proof of concept and utility. The authors claim that these mappings can enable readers, managers and IT experts, to build new insights onto such Business Models and develop requirements for Information System infrastructure. When approaching the Value Creation System as a Value Net the goal is to think outside the conceptual box of Value Chains and understand how the different activities interact, by exposing the multiplicity of value types and flows. In doing this study the authors are attempting to synthesize a new Business Model proposal that could underlie the development of an infrastructure for the collaborative creation, distribution and exploration of online massively multiplayer games, beyond the traditional producer-consumer roles.

• 한국IT서비스학회지
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• 제13권1호
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• pp.161-179
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• 2014

Added value of music industry in Korea is not distributed and calculated properly, and this obstacle brings various problems in a creative environment. Meanwhile, a new business model such as Open Collaboration, Crowdsourcing and platform that makes decisions and innovation from external resources has been appeared in commercial area. This new model like a composer delivers to consumers directly through Youtube.com, and multi collaboration is applied to the music industry, and it enables a new type of mechanism for creation, distribution, division, and calculation of music. However there are not enough empirical study of the music market because existing relative researches has been centered around fundamental concepts and application methodologies. This research defines Open Collaboration Platform in the music industry, and studies affecting factors of Participation Intention for example Justice, Information System Quality and Perceived Value. For a survey we apply PLS(Partial Least Square) to analyse Equity, Information System Quality and structural equation between Perceived Value and Participation Intention. Analysis results show Distributive Justice and Procedural Justice affects Platform Trust, and Service Quality, Economical Value and Emotional Value affects Platform Usefulness. Also Platform Trust and Platform Usefulness affects Platform Participation Intention. We discussed academic and practical implication based on research results.

• 전자공학회논문지 IE
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• 제46권3호
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• pp.12-18
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• 2009

본 논문은 LED 디스플레이 시스템에서 균일하고 부드러운 영상표출을 위하여 각각의 Red, Green, Blue LED의 휘도를 조절하여 흰색보정을 유지할 수 있는 프로세서를 설계하였다. 이 프로세서는 일반적인 LED소자의 특성곡선을 근거로 "a"를 고유특성 값, "b"를 사용시간에 따른 휘도보정 값, "X"를 구동전류 값, "Y"를 휘도 값이라 할 때, "Y=aX+b"로 설정되는 휘도 특성함수에 의하여 각 픽셀의 휘도에 따른 구동 전류 값을 산출하여 휘도를 보정하고, 또한 장시간 사용 시 LED소자의 휘도 저하 문제를 해결하기 위하여 "b"값을 조절하여 LED 디스플레이 시스템의 전체 평균 휘도 값을 상향시킬 수 있도록 구현하였다.

• 한국식품조리과학회지
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• 제15권4호
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• pp.327-337
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• 1999

This study was conducted on a sampling of 700 mixed college students from seven different schools nationwide by written questionnaire to evaluate the value system of convenience foods among Korean college students. Korean students put value on the following categories of convenience foods in order; convenience, taste, price, appearance, appliance to daily life, variety, locality, nutritional value, originality, improvement required, cleanliness and tradition. Significant differences between the sexes occurred in categories as cleanliness and convenience, since females considered convenience foods as convenient but not so clean (safe to eat). This study also conducted factor analysis on 24 individual convenient foods. Noodles laid emphasis on nutritional value; where refrigerated foods, ready to eat (RE) side dishes, on-the-spot kimbab, and sandwiches focused on cleanliness. Noodles. cereal, and instant soup focused on price. Frozen pizza, noodles, retort, RE meat, ham, fish cakes were dependent on locality and traditionality. Noodles, instant food, and packed kimchi scored highly on convenience. Frozen fried rice, retort, instant porridge, instant rice, RE meat, cereal, instant soup, and RE side dishes on consumption on a regular basis. Cereal, refrigerated foods, and RE side dishes laid emphasis on taste. Noodles, instant rice, cereal, ham, and RE side dishes focused on variety. Retort, RE meat, ramen, cereal, ham, and on the spot sandwiches looked to originality, while canned foods was recognized as ‘needing improvement’.

• 대한건축학회논문집:계획계
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• 제35권4호
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• pp.103-114
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• 2019

From the "Recommendation on the Safeguarding of the Beauty and Character Landscapes and Sites"(1962) to the "ICOMOS-IFLA Document on Historic Urban Public Parks"(2017), 'the spatial safeguarding Concept of Cultural Heritage' in International Norms has manifested in various types. In this article, 24 types of International Norms that reflect 'the concept of Spatial Safeguarding in Cultural Heritage' and Korea legal system such as 'Historical and Cultural Environment' were analyzed in the following two aspects. The first aspect is 'Object Type to safeguard' and analyzed in four types such as 'Groups of buildings(A type)', 'Surrounding, Environment, Setting(B type)', 'Cultural landscape(C type)', 'Historic area and Historic towns(D type)'. The second aspect is 'Safeguarding value(analysis elements)' and analyzed in the following tree elements ; 'Landscape value' such as skyline, 'Intangible value' such as the functions of cultural customs, and 'Ecological value' that should preserve life itself. As a result of the study, 'the concept of Spatial Safeguarding in Cultural Heritage' including C and D type and three value which are trends of International Norms are reflected in Korea legal system, and concrete safeguarding methodology is also implemented systematically in case of ecological value. However, intangible values are not specific to the methodology in both International norms and Korea legal systems, and should be developed in the future.

• 농업과학연구
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• 제43권3호
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• pp.481-495
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• 2016

Lily, which is one of Korea's main flower exports, is one of the most important agricultural product in the country. Korean lily farmers have difficulty earning more profit from producing lilies, because of the high cost of lily bulbs. Most lily bulbs used in Korea are imported from the Netherlands. Thus, the Korean government has kept trying to supply more and better Korean lily bulbs. However, many experts have questioned the efficiency and economic value of the Korean lily production system. The purpose of this paper is to analyze the economic value of the production of lily bulbs in Korea. Especially, this study evaluates the economic value of the production systems of Korean lily bulbs and compares the results from several cases. The results of the present study presents some useful findings, as follows: first, two Korean production areas (Gangneung and Jeju) show a positive economic value but one Korean production area (Taean) presents problems causing a negative economic value. Second, the Korean production area in Vietnam currently has trouble in the view of economic value but will likely overcome that problem. Third, the production area in the Netherlands shows the best economic value. Thus, Korean lily bulb producers need to benchmark that system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.139-142
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• 2001

This paper presents a design of two gimbal system. One is two axes stabilized platform that is targeted to preserve direction while vehicle that is adhered antiaircraft fire, radar or EOTS is moving. The system maintains stabilization by recovering error using the rate gyro. The other is three axes gimbal system that is intended to simulate various angle movement in space and to test three axes gyroscope. This system determines gyro condition comparing gyro output value with converted motor encoder value.

• 대한교통학회지
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• 제25권6호
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• pp.209-230
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• 2007

이 논문은 혼잡현상을 갖는 교통체계의 사회비용함수를 사회비용 최소화문제로부터 도출하여 분석하였다. 이 논문은 이 분야의 기존 연구에서 다루지 않았던 다음의 두 가지를 중점적으로 분석하였다. 하나는 이용자들의 시간가치가 다를 경우에 비용함수의 구조가 어떻게 달라지는지를 검토하는 것이고, 다른 하나는 사회비용함수를 구성하는 공급자 비용함수의 구조를 파악하는 것이었다. 분석의 결과는 다음과 같이 요약될 수 있다. 첫째, 한계사회비용은 특정한 시간가치를 가진 고객이 소비한 시간가치비용과 추가 고객의 처리에 수반되는 시스템 전체의 서비스시간 증가에 따른 한계혼잡비용으로 구성된다. 둘째, 한계혼잡비용은 공급자의 보상한계비용과 같은 바, 후자는 공급자가 추가의 고객을 가장 경제적으로 처리함에 필요한 용량의 변경에 의한 서비스시간의 변화 양에 대한 이용자 전체의 시간가치를 보상해준다는 전제아래서의 공급자 한계비용을 지칭한다. 셋째, 보상한계비용은 서비스시간함수가 산출과 용량에 대해 동차함수일 경우 한계용량비용에 시스템 이용률의 역수를 곱한 값과 같다.

• Structural Engineering and Mechanics
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• 제34권6호
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• pp.739-753
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• 2010

Pointing to the design requirement of prestressed space grid structure being the target cable force, the pretension scheme decision analysis method is studied when there's great difference between structural actual state and the analytical model. Based on recursive formulation of cable forces, the simulative recursive system for pretension process is established from the systematic viewpoint, including four kinds of parameters, i.e., system initial value (structural initial state), system input value (tensioning control force scheme), system state parameters (influence matrix of cable forces), system output value (pretension accomplishment). The system controllability depends on the system state parameters. Based on cable force observation values, the influence matrix for system state parameters can be calculated, making the system controllable. Next, the pretension scheme decision method based on cable force observation values can be formed on the basis of iterative calculation for recursive system. In this way, the tensioning control force scheme that can meet the design requirement when next cyclic supplemental tension finished is obtained. Engineering example analysis results show that the proposed method in this paper can reduce a lot of cyclic tensioning work and meanwhile the design requirement can be met.