• 경영과학
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• 제33권1호
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• pp.35-47
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• 2016

Generation of electricity using wind power has received considerable attention worldwide in recent years mainly due to its minimal environmental impact. However, volatility of wind power production causes additional problems to provide reliable electricity to an electrical grid regarding power system operations, power system planning, and wind farm operations. Those problems require appropriate stochastic models for the electricity generation output of wind power. In this study, we review previous literatures for developing the stochastic model for the wind power generation, and propose a systematic procedure for developing a stochastic model. This procedure shows a way to build an ARIMA model of volatile wind power generation using historical data, and we suggest some important considerations. In addition, we apply this procedure into a case study for a wind farm in the Republic of Korea, Shinan wind farm, and shows that our proposed model is helpful for capturing the volatility of wind power generation.

• 아동학회지
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• 제23권3호
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• pp.109-121
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• 2002

The subjects of this validation of the Antisocial Behavior Scale(ABS) consisted of 323 normal and 29 clinically referred preschoolers between the ages of four and six years. The ABS has 3 factors: oppositional/aggression, nonsocial/egoism, and inattention. Results showed high test-retest reliability(r=.83-.90). The scale discriminated between the normal and clinical groups. The first(oppositional/aggression) and the third(inattention) factors of the ABS, measuring externalizing behaviors, correlated highly with the Externalizing Problems and Attention Problems Scales of the Korean Version of Child Behavior Checklist(K-CBCL). The second(nonsocial/egoism) factor of the ABS, measuring emotional areas correlated highly with the Emotional Liability Scale of the K-CBCL.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.149-150
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• 2017

It is known that physical and chemical changes of cement hydrates cause problems in the volume stability of concrete. In order to overcome these problems, there is a growing interest in research on mixing technology of cement-based materials and nanomaterials. Among the nanomaterials, carbon nanotubes (CNTs) are attracting attention due to their excellent mechanical properties. The CNTs are made of cylindrically shaped graphene sheets. According to the number of sheets, single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are classified. Although the SWCNT has superior mechanical properties, the research using MWCNT is vigorous due to the difficulty of marketability and manufacturing, but the research using SWCNT is insufficient. In this study, we investigate the effect of SWCNT on the formation of hydrate of cement paste by observing the microstructure of broken cement paste after measuring the flexural strength of cement paste with SWCNT dispersion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.189-192
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• 2001

Recently, STI process is getting attention as a necessary technology for making high density of semiconductor by devices isolation method. However, it does have various problems caused by CMP process, such as torn oxide defects, nitride residues on oxide, damages of si active region, contaminations due to post-CMP cleaning, difficulty of accurate end point detection in CMP process, etc. In this work, the various defects induced by CMP process was introduced and the above mentioned Problems of CMP process was examined in detail. Finally, the guideline of future CMP process was presented to reduce the effects of these defects.

• 전기학회논문지
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• 제64권12호
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• pp.1718-1723
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• 2015

The diameter of the rotor of 2MW wind turbine is being developed by a number of companies with more than 80m, reliability and economic efficiency of the wind power generator has been improved. The need for large-scale wind turbine with excellent economy has been attracting attention because the new orders and the location of the wind turbine market has reached a limit. Technology development for enlargement of wind turbine is possible not only the improvement of energy efficiency but also reduce the construction costs per unit capacity. However, mechanical gearboxes used in wind generators have problems of wear, damage, need for lubrication oil and maintenance. Therefore, we want to configure the gearbox of a large-scale wind turbine using a magnetic gear in order to solve these problems of mechanical gearbox.

• 한국미생물·생명공학회지
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• 제38권2호
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• pp.124-128
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• 2010

Vaccines, especially for viruses, have been produced from egg-based manufacturing process. The method is simple and easy to set up the manufacturing process. However, the method has many problems in quality control, limit of manufacturing capacity, and ethical issues. Over the last decade, an alternative method, which manufactures vaccines using cell culture-based system, has received great attention to overcome the problems in egg-based vaccine production. This article examines current status and perspectives of cell culture-based vaccine production.

• International Journal of Quality Innovation
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• 제7권1호
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• pp.48-59
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• 2006

The Swedish construction sector has been criticized in media for being corrupted, unproductive and conservative. Several incidents, e.g. cartels, work on the side without paying tax and moisture problems, have had a great deal of attention. Of that reason has the government initiated a number of investigations in order to identify the major problems in the construction industry. Further, they have initiated a development of a tool aimed for (a) to identify risks, (b) to avoid poor quality costs, and (c) to direct towards increased quality and effectiveness in building and civil engineering projects, from a client perspective. The UK Constructing Excellence has often been held up as a model during the debate. However, the Swedish general culture differs from the British, as well as the Swedish system differs from the British. The purpose of this paper is to describe the program for developing the system, including the purposes with the system, identified starting points and demands and the approach/method for the development.

• 한국유기농업학회지
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• 제10권2호
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• pp.51-66
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• 2002

It is almost impossible to aggregate environment-related information, simply because it is vast. Therefore, Recently, the development of an environmental index is attracting the attention in Korea and other nations, since it is taken to be useful for legislating environmental policies. When it comes to the development of an environmental index, the first necessary step is to organize environmental information by using an accounting framework that manifests outstanding consistency and inclusiveness. And then, this organized environmental information should be appropriately used, whenever required. Compared to these movements, it is necessary to point out that the environmental accounts in the agricultural section still suffer from numerous problems that need to be solved. According1y, this dissertation suggests and considers at least the following three matters. First of all, an integrated index evaluation method should be developed, taking domestic and foreign movements into consideration at the time of conducting the environmental evaluation. Secondly, a master plan for the environmental accounts should be developed for the agricultural sector. And thirdly and finally, problems and solutions incurred during the process of performing the aforementioned tasks need to be examined in detail.

• 대한안전경영과학회지
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• 제19권4호
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• pp.53-62
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• 2017

It has come to attention that a risk-assessing organization, that will benchmark a company's safety department, is imperative, following an increase in large-scale SOC-business project, construction of higher-raised buildings, development of underground space; all that have increase accident rates. Having faced problems that arise in firms that demand diversity, complexity and instantaneity, the purpose of the thesis is to arrive at efficient and practical problem-solving means. In order to solve the problems that would surface theoretically during an actual risk assessment, the state of the operation systems of the top five national construction firms having a hazard rate of 0.25 times less than the average rate have been analyzed, while a hierarchal recognition research of the employees who not only function at the operating level but are the practice subjects of a firm, has also been conducted, bringing the main text.

• International Journal of Computer Science & Network Security
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• 제21권12호
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• pp.203-206
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• 2021

The article is devoted to the study of the problems of polygraphic research to obtain forensically significant information. An analysis of the legal basis for the use of the polygraph in Ukraine. Problematic issues concerning the appropriateness of using a polygraph in the investigation and detection of crimes have been studied. The domestic legal norms that regulate this issue, as well as foreign experience are analyzed. The article reveals the essence of the polygraph, the legal basis and requirements for its use. Attention is drawn to the main difficulties of using a polygraph and ways to solve them.