• 한국강구조학회 논문집
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• 제21권6호
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• pp.609-618
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• 2009

본 연구에서는 다양한 설계조건 하에서 철골보의 내화시간을 평가할 수 있는 산정식을 열-구조 연성해석(fully coupled thermo-mechanical analysis)을 토대로 제안하였다. 본 연구에서 제안하는 산정식은 철골보의 화재거동에 미치는 주요 인자를 구조변수 및 열변수로 명시적으로 반영하므로 각 설계변수의 내화성능에 대한 영향을 설계자가 쉽게 정량적으로 파악할 수 있는 강점이 있다. 광범위한 변수해석을 수행하기에 앞서 실물대 화재실험 결과를 활용하여 본 연구의 열-구조 연성해석모델의 타당성을 검증한 후, 철골보에 붕괴처짐(run-away deflection)이 발생할 때까지 화재거동에 대한 각 변수들의 영향력을 검토하였다. 이러한 수치해석결과를 다양한 설계조건에서 철골보의 내화시간 예측에 활용할 수 있도록 다중선형회귀분석을 통해 통계학적으로 신뢰도가 높은 평가식을 제안하였다. 현행 사양설계기준에서의 활용법을 사례를 들어 예시하였고, 제시된 식으로부터 얻어지는 경제성과 장점을 입증하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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• pp.112-118
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• 2012

Fine suspended solids from mine drainage draw attentions due to their potential adverse influences on the water quality, such as increasing turbidity and degrading aesthetic landscape. Currently, sand filter beds are adapted in some mine drainage treating systems. However, more efficient system is in demand, as the existing sand beds reveal some problems, such as frequent maintenance intervals. Various filtering mediums including fly ash, mine tailing aggregates and the sand were tested for improving the current system, using column experimental set-up. Mine drainage samples were collected from the current treating systems in the abandoned H coal mine. The experiment was run for 7 days. Suspended solids recorded as 100.9 mg/L and the value exceeds the current standard, 30 mg/L. Sand was proved to still be the optimum medium for the fine suspended solids, compared to fly ash and fly ash + sand. Mine tailing aggregates were placed at the exit of the columns, substituting gravels. The tailing aggregates is made by mine tailings and clay. Sand bed filters can also be improved by mixing granular activated carbon, which was found to be economical and efficient in the batch experiment, conducted at the same time.

• 한국해양공학회지
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• 제31권2호
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• pp.81-90
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• 2017

The 1MW OTEC (Ocean Thermal Energy Conversion) platform was designed for application in equatorial seas. In this study, the OTEC platform was investigated using numerical and experimental methods. An octagon-shaped OTEC platform was investigated using the Ocean Engineering Basin of KRISO. These experiments included various tests of regular waves, irregular waves and irregular waves with current (wave+current). The responses of the platform in regular waves showed good agreement between the numerical and experimental results, including the motion RAO, wave run up, and mean drift force. The peak period of heave and pitch motions were observed around 0.5 rad/s, and the effect of the total reflection was found under short wave conditions. The standard deviation (STD) of the platform motion was checked in irregular waves of equatorial and Hawaiian seas. The STD of the pitch was less than $4^{\circ}$ different from the operability requirement under equatorial conditions and the surge STD of the wave frequency showed good agreement between the numerical and experimental results. The STD values of the surge and pitch were increased 66.6% and 92.8% by the current effects in irregular waves, but the pitch STD was less than $4^{\circ}$ under equatorial conditions. This study showed that the STD of the surge was affected by spring effects. Thus, the watch circle of the platform and tension of the mooring lines must be evaluated for a specific design in the future.

• 한국시스템다이내믹스연구
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• 제8권2호
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• pp.141-173
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• 2007

In Korean context, the innovative cities imply new towns or urban clusters in the Non Capital Regions, all of which would accommodate the relocated Capital based public organizations. The central government-initiated innovative cities have provoked pros and cons towards their effectiveness and efficacy for the balanced territorial development. From a broader prospective, this paper firstly examines the current status quo of the innovative cities. Based on their master plans, it analyzes physical and non physical factors which would exert significant impact on the innovative cities. Secondly, it pays attention to how key factors strengthen or weaken their behavioral patterns in terms of dynamic location and implementation policies of the innovative cities. Using System dynamics approaches, it sets up couples of scenarios, categorizing between supporting and opposing arguments towards the innovative cities. Lastly, after divulging systematic structure of the innovative cities, it proposes a series of practical alternatives which would contribute to minimizing unexpected side effects or unwanted social cost in the long run. In order to guarantee reinforcing structure of the innovative cities, the paper suggests that QOL (quality of life) variables, which would require continuous investment in the social infrastructure, are pivotal in achieving original goals of the innovative cities. Otherwise, the innovative cities would not be innovative per se. In the worst case, they might be degraded into the unpopular ghost towns.

• World Technopolis Review
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• 제2권2호
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• pp.96-108
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• 2013

Egypt has been known as the light house of science and innovation not only in the Middle East but to the world across ages. Recently, there have been many ups and downs that positioned Egypt in a lower rank that it actually deserves according to its long history. This review entitles the current condition of science, technology and innovation in Egypt and the consequent setting up of best practices of science and technology parks (STPs) experiences. Egypt's science, technology and innovation (STI) system is highly centralized and dominated by the public sector, with R&D happening mostly in state-run universities and research centers supervised by the Ministry of Higher Education and Ministry of Scientific Research. R&D indicators state that Egypt ranking is 40th worldwide for the published articles (around 10,000 papers in 2011), while the numbers of issued patents (350 local and 50 international in 2011) is still far beyond expected. STPs in Egypt are addressed in this review by three examples; smart village in Cairo, Investment zone in Borg El-Arab City and Technology Valley in Ismailia. The three models are discussed in details and a suggested road map for developing more STPs is estimated.

• The International Journal of Costume Culture
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• 제12권2호
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• pp.121-128
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• 2009

The goal of this study is to investigate the current conditions of apparels for the handicapped, identify the problems and recommend what are appropriate and functional apparels for the handicapped. The research method was to statistically process a survey on 200 handicapped by frequency analysis and cross tabulations. The study results are as follows. First, the degree of discomfort in daily activities was shown during toilet use and eating. Among clothes categories owned by the handicapped, most discomfort was felt in the order of everyday clothes, workout clothes, underwear, athletic shoes and working clothes. Second, children's clothing was most commonly preferred clothing style by handicap for the dwarfism. Comfortable clothes was preferred and relaxed, decent, and unique styles were preferred in the order. Soft feeling texture and absorbency was considered important as preferred clothing material. Third, sizes and designs were improvements wanted by the handicapped in apparel in the order. In addition, they wanted to wear apparel sensitive to the fashion just like the non-handicapped without showing the handicapped parts. There is a necessity for the government or municipalitiesto establish and run protected workplaces or independent workplaces for those who have studied apparel. The field is thought to require continuous and numerous follow-up studies such as researches on different physiques, standardization of apparel, segmentation of sizes and methods of producing custom apparel by function and handicap.

• 정보처리학회논문지D
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• 제12D권7호
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• pp.979-984
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• 2005

많은 웹 기반 정보시스템은 여러 가지 클라이언트 장치와 사용자들, 사용자 작업에 대한 시스템의 유저 인터페이스에 관한 적응을 요구한다. 본 논문에서는 개발자가 고수준 마크업 언어를 사용하여 웹 기반 인터페이스를 명세 할 수 있는 웹 기반 정보시스템에 적합한 클라이언트인터페이스를 제공하기 위한 새로운 접근방법을 제시하고자 한다. 단일 인터페이스 명세는 실행 시에 다중 웹 장치에 대한 인터페이스를 자동으로 제공하기 위한 것이다. 본 접근방법은 개발자들이 웹 기반 유저 인터페이스를 현재 다른 접근 방법들보다 더 쉽게 구성하고 유지할 수 있게 할 것이다.

• 대한조선학회논문집
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• 제53권1호
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• pp.1-9
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• 2016

It is important to research and understand the physical phenomenon around a semi-submersible offshore structure on waves and currents because the wave run-up and load occurs owing to the waves and currents. In this study, the numerical simulations are performed about flow around a fixed semi-submersible offshore structure. The Modified Marker-density method is adopted in the present computation procedure, this method is one of the various methods to define the free-surface. The present computation results are compared with existing experimental and numerical simulation(VOF method) results. And, the computation results are relatively coincident with the existing results of model test and numerical simulation by VOF method.

• 한국초전도ㆍ저온공학회논문지
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• 제14권1호
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• pp.25-29
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• 2012

The novel type of cable under consideration is cooled by gaseous Helium at elevated pressure. Helium is known for having poor electric breakdown strength; therefore the dielectric capabilities of this type of cable must be tested under conditions similar to the envisaged operation. In order to study the dielectric performance we have designed and built a novel high pressure cryostat rated at 2.17 MPa which has been used for testing model cables of lengths of up to 1 m. The cryostat is an open system where the gas is not re-circulated. This allows maintaining a high purity of the gas. The target temperature range is between 40 K and 70 K. This substantially increases the critical current density of the HTS compared to 77 K, which is the typical temperature of cables cooled by liquid nitrogen. The cryostat presented allows for adjusting the temperature and keeping it constant for the time necessary to run a complete dielectric characterization test. We give a detailed description of the cryostat. Measurements of partial discharge inception voltages as well as the temperature distribution along the model cables as a function of time are presented.

• 가정과삶의질연구
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• 제21권4호
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• pp.41-53
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• 2003

The purpose of this study is to understand and verify the incentives as an important market environment and to help consumers use them effectively, and consequently to improve the consumer welfare. This study examined the representative incentive, the sales promotions which can effect on the consumer decision making process and current issues of them. For the purpose, a coffee specialty store was hypothesized and the subjects were 20∼30 years old, since the sales promotions can be more effective toward the younger consumers making their decisions low-involvement goods and services. The conclusions can be summarized as follows; Consumers understand the advantages and disadvantages of sales promotion very well, and use them rationally and usefully to maximize their satisfaction. the sales promotions act as incentives in the all steps of decision making processes. Generally, consumers prefer to get things at a good price, so in this survey, the discount coupons and the point accumulative membership had more effect than others. Consumers pointed out controversial issues of the sales promotions as follows: the sales promotions could bring about cost rising and unnecessary and/or impulse buying, and stir up speculative motivation. These are common serious problems in the sales promotions. The sales promotions are very useful tools in promoting sales but not fundamental in the long run. Marketers and manufacturers should keep it in mind that the best way to satisfy the consumers is to keep all things in good quality and moderate price.