• Reproductive and Developmental Biology
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• 제41권2호
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• pp.33-40
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• 2017

X-chromosome inactivation is one of the most complex events observed in early embryo developments. The epigenetic changes occurred in female X-chromosome is essential to compensate dosages of X-linked genes between males and females. Because of the relevance of the epigenetic process to the normal embryo developments and stem cell studies, X-chromosome inactivation has been focused intensively for last 10 years. Initiation and regulation of the process is managed by diverse factors. Especially, proteins and non-coding RNAs encoded in X-chromosome inactivation center, and a couple of transcription factors have been reported to regulate the event. In this review, we introduce the reported factors, and how they regulate epigenetic inactivation of X-chromosomes.

• 동력기계공학회지
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• 제18권3호
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• pp.93-99
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• 2014

The purpose of this paper is to manufacture the non-sintered ceramic used lime and industrial waste. The used materials were basalt powder sludge, calcium hydroxide(Ca(OH)2) and additives such as calcium stearate and $TiO_2$. The mixing ratios between Ca(OH)2 and sludge were 5:5, 6:4 and 8:2, respectively. The ceramic forms were pressured by 100, 200 and 300 bar and cured in 14% CO2 for 12 days. The behaviors of compressive strength, specific gravity, water absorption and pH of ceramic form were investigated. The results were compressive strength of over 36 MPa, water absorption of over 8.8%, pH value of over 12.3. And these results satisfied GR F 4006 and 4031 standard.

• 상하수도학회지
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• 제30권1호
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• pp.51-58
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• 2016

On account of the increase in water demand and climate change, droughts are in great concern for water resources planning and management. In this study, rainfall characteristics with stationary and non-stationary perspectives were analyzed using Weibull distribution model with 40-year records of annual minimum rainfall depth collected in major cities of Korea. As a result, the non-stationary minimum probable rainfall was expected to decrease, compared with the stationary probable rainfall. The reliability of ${\xi}_1$, a variable reflecting the decrease of the minimum rainfall depth due to climate change, in Wonju, Daegu, and Busan was over 90%, indicating the probability that the minimal rainfall depths in those city decrease is high.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1988년도 추계학술대회 논문집
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• pp.98-101
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• 1988

The material system (Bi$\sub$0.7/Pb$\sub$0.3/)Sr$_1$Ca$_1$Cu$\sub$1.8/Ox forms, at 845$^{\circ}C$, two major phases having a high Tc(100K) and a low Tc(∼70K) both of which consists of platelets and a non-superconducting minor phase which has rod-like shape and isolated by the major phases. As the sintering period increases, the amount of high Tc phase increases accompanying the decrease in low Tc phase while the amount of the non-superconducting phase is sintering period independent, resulting in a superconductor with Tc of 100K. Changes in compositions of each phase also occur during sintering due to evaporation of bismuth and lead.

• 한국항공운항학회지
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• 제6권1호
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• pp.125-145
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• 1998

The term "Privatization" has a different meaning in different contexts and cultures. In this paper, the term "Privatization" in the context of airports is defined as the movement of an entity from the government sector to the private sector. This is the definition that is commonly employed in the U.S. Airport revenue can he divided into two sub-categories of aeronautical revenue and non-aeronautical revenue. At many of the major international airports, however, non-aeronautical revenue has been growing faster than the aeronautical revenue, contributing an increasingly larger share of the total revenue. And the best way to enhance simultaneously the airport operations. With the remarkable growth in the air traffic volume of pssengers and cargo. more and more mega-international airports have been built or are under construction. As the air transport demand is expected to increase at an even greater rate in the 21st century, new types of airports which will be free of current major problems. such as airport congestion and flight delays are badly needed.

• 한국식품저장유통학회지
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• 제4권1호
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• pp.1-10
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• 1997

This study was performed to determine chemical compositions of dried persimmons stored with plastic film at low temperature and the effect of film packaging on dried persimmons during storage. The moisture contents of dried persimmons were 30 to 36% and alcohol contents were 264 to 318 mg/100g and acetaldehyde contents were 25 to 40mg/100g. Total lipid contents of dried persimmon were 626 to 869mg/100g and oleic, palmitic, linolenic, and palmitoleic acid were major fatty acids in total lipids. Major amino acids were glutamic acid, arginine, cystine and aspartic acid. From the result of storage experiment, non-packed group was that hardness was high as decreased in moisture content. In case of film packed groups stored at 5$^{\circ}C$, self life was longer than non-packed and packed groups stored at room temperature. But, it need to develop available packing material and storage method.

• 한국멀티미디어학회논문지
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• 제22권4호
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• pp.472-479
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• 2019

Today, computational thinking takes an important role in problem solving in software education. As a result, software education as liberal arts for non-CS major students is rapidly expanding. It is necessary to study the effects of computational thinking on software problem solving ability compared to traditional programming language education. In this paper, we propose an evaluation model for analyzing the effects of computational thinking on the overall software development process, and analyze how the problem solving process is different for learners who take computing thinking classes and programming language courses as liberal arts courses. As a result, students who learned computational thinking showed higher ability in problem analysis and design process.

• 한국환경복원기술학회지
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• 제8권6호
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• pp.21-33
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• 2005

This study aims to find out actual conditions of environmental-friendly design on outdoor space of housing estate, and then to propose the direction of environmental-friendly design in order to construct the adequate environmental-friendly housing estates. First of all, this study investigated the environmental-friendly design elements on outdoor space of housing estates through literature survey and selected 9 major elements based on the result of the investigation. And then 15 KNHC housing estates were analyzed to find out design actualities of environmental-friendly elements. Major results of this study are as follows. 1) The environmental-friendly design elements were highly adopted in outdoor space of housing estates. The adoption rate of environmental-friendly design elements is 81.0% in average. But, 5 major elements were passively adopted out of 9. 2) According to the comparative analysis of KNHC housing estates, The adoption rate of environmental-friendly design elements was similar in metropolitan housing estates and non-metropolitan housing estates. But, the adoption level of environmental-friendly design element in metropolitan housing estates was higher than one in non-metropolitan. It shows that metropolitan housing estates are more activly adopted in 6 major elements. 3) According to the comparative analysis of design method of KNHC housing estates, The adoption rate and the adoption level of environmental-friendly design elements by turn-key design method and competition design method were higher than by general design. It shows that the housing estates designed by turn-key and competition design method are more activly adopted in 7 major elements.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2910-2916
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• 2011

Environmental conservation is becoming the major conversation topic in the 21st century, the era of environment. In the Law for the Preservation of Water Quality, article 53 states "A business unit which is doing business causing pollution caused by non-point pollutant or builds waste water discharge facilities, should report the installation of the non-point pollutant and install the required pollution control facilities". Environmental pollution caused by oil leaks during operation or maintenance has been found in the railway sector. Especially, rolling stock depot is most likely to be affected by environmental pollution. Therefore, in this paper We have investigated non-point pollutant in the rolling stock depot area and have studied adequate disposal method to minimize the effect of the non-point pollutant, hoping to supply the preliminary data for building an environment-friendly rolling stock depot.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.228-234
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• 1998

The buckling is one of the major two nonlinear problems. One is the material non-linearity and other is the geometrical nonlinear. Material non-linearity has occurred when the buckling stress of material exceeded the yield stress of material. The material non-linearity must be taken into account when the buckling analysis of thick plate is performed. In this study, inelastic modulus that is used to calculate the buckling strength is taken to account for the material non-linearity. The results from experiments are used to formulate the semi-theoretical formula. The analysis results generated by the use of semi-theoretical formula are close to the experimental data.