• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1732-1750
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• 2010

Operation of KORAIL's level crossing is in charge of KORAIL. As taking over existing level crossing to KORAIL, they do not conduct risk assessments, so we do not know about any possibilities of inner risk. And present operation of safety of the level crossing is just regular checking of reaction and functions of safety equipments physically, we need to react to the changes of what's going on around of level crossing and incestigation of traffic flow and surrounding conditions more spontaneously. So, we have to prepare the strategies against accidents of level crossing cost-effectively based on regular risk assessments for sustainable safety improvements and overcome operational problems of present level crossing's safety. Here, we're going to investigate the level of safety level and present risk factors of the level crossing using risk assessments for accidents/error of the equipments to show operational strategies of level crossing based on risk assessments.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2401-2405
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• 2008

In the present study, a three-dimensional least square/level set based two-phase flow code was developed for the simulation of three-dimensional sloshing problems using finite element discretization. The present method can be utilized for the analysis of a free surface flow problem in a complex geometry due to the feature of FEM. Since the finite element method is employed for the spatial discretization of governing equations, an unstructured mesh can be naturally adopted for the level set simulation of a free surface flow without an additional load for the code development except that solution methods of the hyperbolic type redistancing and advection equations of the level set function should be devised in order to give a bounded solution on the unstructured mesh. From the numerical experiments of the present study, it is shown that the proposed method is both robust and accurate for the simulation of three-dimensional sloshing problems.

• 한국식생활문화학회지
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• 제17권5호
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• pp.578-583
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• 2002

The purposes of this study were to a) find out the operational characteristics of the contract-managed highschool foodservice in Seoul, b) investigate the expected level of meal-price and facilities investment cost perceived by contract-managed highschool foodservice managers c) compare the present level and expected level of meal-price and facilities investment cost. From October 12 to November 13 in 2001, the questionnaires were mailed to 249 high schools which was managed by contract foodservice company with respondent rate 40.2%. Data were analyzed using SPSS Win(10.0) for descriptive analysis and one group paired t-test. The results of this study were as follows ; 1. The student enrollment of highschools run by contract-managed foodservice was 1,243 with 72.6% participation rate of school lunch program. The average meal-price was 2,138 won. The average annual period of school foodservice operation was 156.78 days per year. The average contracting period was about 3 years. 2. The average cost concerned in the facilities investment amounts 169,578,180 won at the initial investment and 25,204,092 won at the repairs and maintenance cost in the course of operation. 3. The present level of meal-price and facilities investment cost were respectively 2,136won/meal and 171,157,336.72 won. And expected level of meal-price and amount of facilities investment cost were 2,418.75 won and 121,353,215.19 won. Comparing the present level with the expected level of the meal- price and facilities investment cost, expected level of meal-price was significantly higher than the present level of meal-price(p<.001) and expected level of facilities investment cost was significantly lower than present level of facilities investment cost(p<.001).

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.113-118
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• 2001

We present a new interface tracking method for computing two-phase flow. This method is based on VOF method coupled with Level set method. The method is verified to calculate an interfacial curvature accurately as well as to achieve volume conservation during the whole computation period. We apply the present method to calculate a falling drop. The calculated shape and terminal velocity of the falling drop showed good agreement with the data reported in the literature. Also, the present method was proven to be applicable to drop-wall collision phenomenon.

• 한국정보시스템학회지:정보시스템연구
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• 제12권2호
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• pp.189-208
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• 2003

The purpose of this study was to survey current status of information technology literacy in Korean teachers and to give some suggestions for the preparation of prospective teachers in Korea. To achieve the purpose, data were collected using on- and off-line surveys containing questionnaires developed by the researchers. The survey items were categorized into 11 groups such as operation capability, computer use and communication, word processing, ethics, computer fundamentals, understanding of educational IT, information instruments use, application s/w use, work processing with computer, and internet use capability. Major findings were as follows: (1) Female teachers rated their IT literacy level higher than male teachers. (2) Teachers with longer teaching experience rated their IT literacy level lower than those of shorter experience. (3) There were no signigicant differences among sex, school, job grade of teachers at the present level of literacy, but there were significant differences among sex, age, carreer, job grade, and subject matter at the expectation level except for school grade.

• 한국지형학회지
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• 제24권3호
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• pp.13-25
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• 2017

This study is quantitative reconstruction of palaeo sea level records around Sinduk-ri, Gochang-Gun. 7 cores were collected from GC14 to GC18 in order to examine the entire sedimentary facies and reconstruct the sea level records. The cores were analysed by AMS, sedimentary facies, diatom and WA-pls. As a result of the diatom analysis, diatom zone were classified as No diatom zone, B1 zone, M zone and B2 zone. The result of WA-pls was that the sea level was about 1.5m lower than the present level around 6,000 BP and about 1m lower during last 5,000 BP. Thereafter, sea level rose to the present during the Mc sub-diatom zone period. Moreover, during the Md sub-diatom zone period, sea level was about 0.5m higher than the present.

• 한국과학교육학회지
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• 제7권1호
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• pp.53-68
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• 1987

To figure out the present status of Korean middle school science curriculum in the national level is not an easy job. especially in the restricted condition such as this research project. Therefore, to achieve a meaningful result, the case study type of research was adopted In the study five middle schools (2boy's and 3girl's)were selected and examined intensively. In this study, two major works were done. One was the analysis of the present middle school science curriculum and the other was to examine the current status of the administration of the curriculum in schools. This first study focused on the evaluation of the current Curriculum. Acording to the result, the objectives stated in the teachers guide and implied by the testbook were heavily concentrated on the knowledge level in Boom's taxonomy. Achievement on the objectives which were selected as important were very low. The average pass rate for the selected objectives was less than 50% of the students. This means the content level of the present science curriculum is not appropriate. The study suggested that the present middle school science curriculum should be revised and the content should be replaced with easier topics to match the students cognitive level. The study also suggested further studies to measure the cognitive level of Korean students in national scale.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년도 춘계학술발표대회 논문집
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• pp.427-430
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• 2008

The present study is a preliminary research improving the dwelling quality of apartment house as a kind of multi-family housing. The purpose of the study is to find out the present condition on noise level and types including residents' living noise in apartment units. The method was field survey consisted of field measurements on equivalent noise level, observation on noise type, and interview on residents' responses. The results are as follows. 1) Averages of indoor noise levels of subject houses were measured as $43.9{\sim}62.2\;dB(A)_{Leq5min}$, the average of each house except one was higher than the permissible level, 45 dB(A). 2) The noise types observed were mostly residents' living noise and classified as 'water hammer', 'living equipment noise', 'noise by family', 'hood noise', and 'kitchen noise' in own unit, 'walking and talking noise in stairs and corridors', 'noise by neighborhood house', 'noise by the upper story' in building, and outdoor noise. 3) The residents show slightly non-positive responses at 'noise by the upper story', 'noise by neighborhood house', 'water hammer', and 'noise by family'. Therefore, it is required to plan for preventing deterioration of the sound environment quality by residents' living noise in own unit as well as by neighborhood houses.

• 한국지형학회지
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• 제18권4호
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• pp.235-246
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• 2011

해안충적평야에서 얻은 연대측정 자료와 미화석 연구 결과 및 퇴적상을 통해 복원된 홀로세 해수면변동 곡선은 기후변화의 내용을 포함하고 있다. 6,000~5,000년 전은 '해진극상기'이며 '기후최적기'로서 중부유럽에서 여름기온은 현재보다 2~3℃ 더 높았다. 당시의 한반도 해수면은 현재보다 0.8~1.0m 더 높았으며, 현재보다 더 온난하였을 것으로 추정된다. 특히 한반도에서는 2,000~1,800년 전에 해수면이 현재보다 1.1~1.3m 더 높은 수준에 도달하였으며, 기후최적기에 버금가는 정도로 온난하였을 가능성이 있다. '서브보레알'에는 중부 유럽의 기온이 현재보다 2~3℃ 더 낮았음에도 불구하고, 이 시기 우리나라의 해수면은 현재보다 높았다. 홀로세 중기 이후 해수면이 가장 낮았던 2,300년 전 경에도 현재와 유사한 고도에 있었다. 이와 같은 사실에서 볼 때, 한반도에서 복원된 해수면변동 곡선은 한랭한 시기의 기후환경을 정확하게 반영하지 않은 것으로 생각된다.

• Advances in Energy Research
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• 제5권1호
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• pp.57-64
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• 2017

Electricity is basic need for country development. But at the present time proper planning and policy is require at high pace for power generation network extension due to the increasing population growth rate. Present study aimed to analyze the present and future demand for electricity at household level in Province of Balochistan of Pakistan via simulation modeling. Data of year 2004-2005 was used as baseline data for electricity consumption to predict future demand of electricity at both rural and urban domestic level up to subsequent 30 years, with help of LEAP software. Basically three scenarios were created to run software. One scenario was Business-As-Usual and other two were green scenarios i.e., solar and wind energy scenarios. Results predicted that by using alternative energy sources, demand for electricity will be fulfill and will also reduce burden on non-renewable energy sources due to the greater potential for solar and wind energy present in Balochistan.