• Journal of The Korean Association For Science Education
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• v.19 no.3
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• pp.389-399
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• 1999

The purpose of this study was to identify children's mental models of the free-fall objects. This study examined children's prediction and observation about the free-fall of objects. The experimental procedure involved conducting interviews with first-, third-, fifth-, and seventh grade students. The interview had three phases: Prediction, explanation, and observation. During the prediction phase, the object pairs which varied on the dimensions of size, weight, shape, color were presented to students. The students were asked to predict what would happen if the objects were dropped simultaneously. During the explanation phase, the students were asked to explain how they arrived at their answers. During the observation phase, the students observed the free-fall of the object pairs and were asked to describe what they saw. The results showed as follows. (1) Fifth-and seventh grade students made more correct predictions than first- and third grade students. (2) The conflict problems, object pairs involving the dimensions of size and weight, were the most difficult for students to accurately predict. (3) With regard to observations, there was a non-significant effect of grade, indicating equivalence in the number of correct observations made by first-, third-, fifth-, and seventh graders. (4) The conflict problems were the most difficult for students to correctly observe. (5) First- and third grade students showed a significant difference between prediction and observation about the free-fall of objects. However. no difference was found in the fifth- and seventh grade students.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.446-453
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• 2018

This study analyzed the effect of related party transactions on the corporate value of Korean firms using panel data regression analysis. We tested the efficient transaction hypothesis and conflict of interests hypothesis which concern related party transactions. Five types of related party transactions were considered, including long term supply contracts, assets and business transfers, affiliate loans, equity investment, and credit offerings. If related party transactions were conducted for the purpose of enhancing corporate efficiency, results would have a positive effect on firm value. If related party transactions were conducted for the purpose of private profits of the controlling shareholders, the results would show a negative effect on firm value. Results were as follows. Firstly, it is confirmed that affiliate loans, equity investment, and credit offerings had negative effects on firm value. This implies that these types of related party transactions used by controlling shareholders for the purpose of their private profit, which supports the conflict of interests hypothesis. Secondly, it was found that long term supply contracts and assets and business transfers had no effect on firm value.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.393-401
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• 2000

The feline chemotactic factor(s) for polymorphonuclear cells (PMN) in culture supernatant from mononuclear cells (MNC) treated with egg white derivatives (EWD) were examined. Culture supernatant from MNC treated with EWD and human recombinant (hr) IL-8 remarkably enhanced chemo-taxis of feline PMN. To investigate feline chemotactic factor(s), gel electrophoresis was performed with culture supernatant from MNC treated with EWD under denaturing (18% loading gel/5% stacking gel) and nondenaturing (12.5% loading gel/5% stacking gel) condition. Hr IL-8 and culture supernatant from MNC treated with EWD yielded a distinct band in a molecular weight, 6 to 8 kDa. Eluted solution from gel slices of 6 to 8 kDa band in denaturing condition also enhanced feline PMN chemotaxis. These chemotactic activities of feline PMN induced by culture supernatant from MNC treated with EWD, hr IL-8 and eluted solution were inhibited in a dose-dependent manner by rabbit anti-feline polyclonal IgG (RAF pIgG) and monoclonal antibody (mAb) against hr IL-8. RAF pIgG also showed a binding activity with hr IL-8, suggesting that RAF pIgG against feline IL-8-like chemotactic factor(s) had cross-reactivity with human IL-8. These results suggested that feline MNC treated with EWD might release feline IL-8-like chemotactic factor(s) with a molecular weight, 6 to 8 kDa, which induces the chemotaxis of feline PMN.

• Spatial Information Research
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• v.22 no.5
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• pp.99-107
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• 2014

The purpose of this study is to formulate various improved working schemes in determining the definition of non-permissible activities to strengthen the practical implementation and operation of the integrated coastal management plan for regional self-governing authorities In this study, non-permissible activities indicate any activities which should be restricted according to the coastal functions of five different sectors in the regional plan for coastal management. Coastal management plan, are classified into four areas along the coast to use direction. It prohibited and support matters of another coastal exploitation each area. If you want to set the coastal area, has already been specified in the regional and global based on that region Land use planning and urban planning. When additional area settings in some cases may lead to conflicting results. Analyzes the factors to consider about the range and use areas set of in coastal management, It is necessary to strive for deriving a scheme to solve the existing contradiction between the state of the local - area specified problem. With the help of marine spatial planning and pointed out institutional and urban planning system to be utilized in land in the ocean for a more accurate and efficient coastal management, and registered the coastal areas, there is a need to manage. Land -use planning, consideration of another consultation body organization that is able to develop a plan that was comprehensive and marine spatial planning, The contradiction consider to specify the various areas and regions where other specific identification method is determined, Setting the range of coastal waters (within 3 nautical mile), I was exploring the coast registration scheme and registration target, etc.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4D
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• pp.351-360
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• 2010

In 2010, the number of registered vehicles reached almost at 17.48 millions in Korea. This dramatic increase of vehicles influenced to increase the number of traffic accidents which is one of the serious social problems and also to soar the personal and economic losses in Korea. Through this research, an enhanced intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network will be developed in order to obtain the important data for developing the countermeasures of traffic accidents and eventually to reduce the traffic accidents in Korea. Firstly, this research has investigated the influencing factors of road geometric features on the traffic volume of each approaching for the intersections where traffic accidents and congestions frequently take place and, a linear regression model of traffic accidents and traffic conflicts were developed by examining the relationship between traffic accidents and traffic conflicts through the statistical significance tests. Secondly, this research also developed an intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network through applying the intersection traffic volume, the road geometric features and the specific variables of traffic conflicts. Lastly, this research found out that the developed model is better than the existed forecasting models in terms of the reliability and accuracy by comparing the actual number of traffic accidents and the predicted number of accidents from the developed model. In conclusion, it is expect that the cost/effectiveness of any traffic safety improvement projects can be maximized if this developed intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network use practically at field in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.5
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• pp.30-42
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• 2023

Various studies have been conducted using microtraffic simulation (VISSIM) to analyze the safety of traffic flow when introducing autonomous vehicles. However, no studies have analyzed traffic safety in mixed traffic while considering the driving behavior of general vehicles as a parameter in VISSIM. Therefore, the aim of this study was to optimize the input variables of VISSIM for non-autonomous vehicles through genetic algorithms to obtain realistic behavior. A traffic safety analysis was then performed according to the penetration rate of autonomous vehicles. In a 640 meter section of US highway I-101, the number of conflicts was analyzed when the trailing vehicle was a non-autonomous vehicle. The total number of conflicts increased until the proportion of autonomous vehicles exceeded 20%, and the number of conflicts decreased continuously after exceeding 20%. The number of conflicts between non-autonomous vehicles and autonomous vehicles increased with proportions of autonomous vehicles of up to 60%. However, there was a limitation in that the driving behavior of autonomous vehicles was based on the results of the literature and did not represent actual driving behavior. Therefore, for a more accurate analysis, future studies should reflect the actual driving behavior of autonomous vehicles.

• Journal of Korea Fair Competition Federation
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• no.128
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• pp.2-5
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• 2006

출자총액제한제도는 그 순기능.정기능이 논의되는 와중에서도 소기의 임무를 완수하고 정리단계에 들어섰다. 그 대안으로 순환출자금지제도가 유력하게 부각되고 있으나 그 논리적 타당성에도 불구하고 각계각층의 의견 상충으로 확실한 결론에 이르지 못하고 있다. 한편 우리 회사법에 규정된 상호출자금지규정도 대규모기업집단의 상호출자 규율에는 역부족이다 아무쪼록 대기업집단의 소유지배구조가 개선되고 시장감시장치가 효과적으로 작동될 수 있는 새로운 제도의 모색에 온 국민이 지혜를 짜 모아야할 때이다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.290-291
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• 2011

전력산업이 발전함에 따라 전력품질 요구도 증가하고 있으나 고조파왜형률에 대한 국제기준이 제조사와 운영자의 입장에 따라 계산방법이 상충되는 부분이 현실적으로 존재하고 있는 것으로 검토되었다. 본 논문에서는 원자력발전소에 사용되는 축전지 및 충전기의 시험 및 관리규격인 ANSI/IEEE 519와 NEMA PE-5에 대한 THD 계산방식에 대한 차이점을 설명하고 현장 규제경험 사례를 통해 바람직한 관리 방향을 제시하고자 한다.

• Defense and Technology
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• no.7 s.281
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• pp.60-65
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• 2002

방위산업과 연계된 군수조달시장은 쌍방 독점의 형태를 가진다. 민수품에 비해 고도의 특수한 기술이 요구되는 경우가 많기 때문에 설비에 대한 높은 투자비용이 소요되게 된다. 수요자인 정부의 목표는 고품질의 방산제품을 적시에 그리고 적정한 가격으로 확보하는 것 이면에는 방산업체를 장기적으로 보호.육성해야 하는 의무도 가지고 있다. 이의 상충되는 목표를 효과적으로 조화함으로써 원가계산체계를 개선하여 적정한 원가산정이 방산업체와 정부 모두에게 가장 최선의 해결책이 될 수 있다.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.482-484
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• 2008

본 연구는 신재생에너지 발전차액지원제도의 기준가격이 보급규모를 제어할 수 없는 제도적 한계를 보완하여 시스템적으로 기준가격이 조정될 수 있는 유연감소율 메커니즘을 제안한다. 제안한 유연감소율 메커니즘은 시장의 보급규모에 따라 기준가격을 시스템적으로 조정함으로써 시장여건의 반영체계를 갖추어 가격조정에 대한 이행당사자간의 이해상충 문제를 완화하는 수단으로 활용될 수 있다.