• 한국자동차공학회논문집
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• 제3권2호
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• pp.51-61
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• 1995

A coast down test mothod has been used to determine the resistance forces on running vehicle due to the aerodynamic drag, rolling resistance and driveline resistance. Most of the tests, however, are based on the Velocity-Time measurements, which require a sophisticated velocity measuring device and contain much error by nature. In the present study a coast down test method based on Distance-Time measurements is introduced, which contains the original idea of Russian scientist Prof. Petrushov along with the suggestions for improvement of the accuracy.

• 한국환경과학회지
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• 제9권1호
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• pp.19-25
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• 2000

As the tideland reclamation is done on a large scale these days, construction work is active in the coastal areas. Facilities in the coastal areas must be built with the tide characteristics taken into consideration. Thus the tide characteristics affect the overall reclamation plan. The analysis of the tide data boils down to a harmonic analysis of the hourly changes of long-term tide data and extraction of unharmonic coefficients from the results. Since considerable amount of tide data of the West Coast are available, the existing data can be collected and can be used to obtain the temporal changes of the tide by being fitted into the tide prediction model. The goal of this thesis lies in assessing whether the mean sea level used in the field agrees with the analysis results from the long-term observation data obtained with their homogeneity guaranteed. To achieve this goal, the research was conducted as follows. First the present conditions of the observation stations, the land level standard, and the sea level standard were analyzed to set up a time series model formula for representing them. To secure the homogeneity of the time series, each component was separated. Lastly the mean sea level used in the field was assessed based on the results obtained form the analysis of the time series.

• Journal of Plant Biology
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• 제1권1호
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• pp.11-20
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• 1958

I. Assumption: Mo-kam-ju, Koelreuteria paniculata is a woody plant mainly cistributed over Northern China. Its sporadic growth along the beaches of Korea and Japan is assumed to have been sowed by the seeds transported adrift on the current across the ocean. II. Use and Growth of the Plant: In China, this plant has been cultivated from early times mainly at temples, it seeds being used as rosaries, its flowers for yellow dyes and medicine for the eyes, and its leaves for black dyes. In Korea and Japan, these plants have been cultivated at temples and used as the material for rosaries. No natural growth of these plants was reported until 1919. III. Discoveries: In this domestic area, Dr. Chung Tae Hyun discovered the plant on the beach between Cho-Do and Chang-san-kot, Hwang-Hae Prov. in 1920. The reporter discovered them on the beach at Buk-Ni, Duk-jok-Do in 1948, at An-Hung in 1956 and on the beach at An-min-Do in 1957. In the Japan area, it was discovered for the first time twenty years ago, mainly along the coast line of the Japan Sea and some along the eastern coast line, at Subo, Yamaguchi Prefecture facing the Pacific Ocean. IV. Study and Experiment: A. Seed The seed coat is thick, non-permeable and floatable. A number of seeds were immersed in artificial sea water and fresh water separately. The seeds remained there for a hundred and forty-five (145) days from April 6, 1957 to August 29, 57. Thirty one seeds out of the fifty immersed in salt water and twenty seeds out of the fifty immersed in fresh water remained on the surface of the water, proving them to be non-permeable to both sea and fresh water. Of course, these had retained their germinating capabilities. Five (5) seeds out of twenty from the fresh water and six (6) out of thirty-one from the sea water were successfully germinated after a hole had been drilled in the seed coat and they had been planted. Thus their floating capability, non-permeability and germinating capability after a possible 145 day trip on the flowing currents has been proved satisfactory according to the assumption made above. B. Current As shown in the Data 2 and 3, the sea current initiated in the Pohai Sea flows westward down along the coast line of Korea reaching the southern part during the autumn and winter seasons. This fact also is in favor of the reporter's assumption. V. Discussion and Conclusion: The reporter concludes that, as discussed above, Koelreuteria paniculata which originates in Northern China is transported adrift on the flowing sea current to our western coast line, and also the coast lines of Shantung and Kuangtung of China and it is germinated on the sandy beaches forming new plants. Thus, the seeds drifted down on the southern beach of Korea and have been transported to the Japanese coast, adrift on the Tae-Ma current. Upon fruition, the seeds of the plants which settle on the coasts of western Korea and Japan will migrate to new places. It can be, however, assumed that while the thickness and nonpermeability of the coat enables the long travel in the water, this also can compose a difficulty in germination, consequently in developing a new distribution of this species.

• The Korean Journal of Ecology
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• 제20권4호
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• pp.275-283
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• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• 한국자동차공학회논문집
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• 제3권3호
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• pp.1-8
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• 1995

In the companion paper of the present paper, a coast down test method to determine the resistance forces on running vehicle based on the distance-time measurement was explained along with the suggestions to improve its accuracy and testing methodology. In the present paper some of the suggestions discussed previously are implemented and actually road tested to see the applicability of the improved method(short distance method) in the field. From the results. it is shown that the short distance method which requires only 600m long proving ground road gives at least comparable results on the accuracy compared to the original S-t method which requires 2000m. It is hoped that the present method be further refiend to give more accurate results.

• 공연문화연구
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• 제36호
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• pp.441-471
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• 2018

동해안굿은 대한민국의 동해안 일대 해안선을 따라 강원도 고성 일대에서 부터 부산지역에 이르기까지 어촌마을에서 행해지는 굿이다. 동해안굿은 거의 세습무를 중심으로 연행되는데, 이 논문은 동해안굿의 세습무 집단 중 김석출 무계의 학습 양상을 세습무와 학습무로 구분하여 살펴보고 이를 토대로 변화하고 있는 동해안굿 학습 양상이 가진 의미를 규명하는 데 의의가 있다. 세습무는 집이 곧 교육 현장이었다. 어릴 때부터 굿판에 따라다니며 소리며 춤을 연행하게 해보아 실전경험을 쌓을 수 있었다. 그러나 대를 이어 무업을 계승해오던 세습무 가계에서 더 이상 자손들이 무업을 이어받지 않게 되면서 무업의 계승과 학습 방식에 변화가 발생했다. 1980년대 이후부터 굿이 가, 무, 악이 어우러진 종합예술로 인정받아 국가 및 각 시도 무형문화재로 지정받고, 예술대학 등에서 전공교육과정으로 편성되어 무속을 전공한 새로운 학습무들이 등장하게 되었다. 이들 학습무는 대학, 동해안별신굿보존회, 굿이 진행되는 현장 등에서 동해안별신굿의 연희 능력을 체계적으로 전승받고 있다. 시대의 변화에 따라 세습무가 학습무들을 받아들여 무업을 계승해나가며 굿의 연행 집단과 굿을 수용하는 마을 사람들의 인식에도 변화가 나타났다. 과거와 달리 굿이 한국전통예술의 원형으로 가무악 총체적 학습의 산물로 인정받으며 국가무형문화재로 지정을 받게 됨으로써 무당의 사회적 지위와 개인적 자존감이 매우 높아지게 되었다. 과거 천시 당하던 무당이 아닌 대내외적으로 인정받는 전통예술인으로 자리 잡게 되면서 굿 현장이나 마을사람들과의 관계에서도 그 지위나 대우가 많이 달라졌다. 마을 구성원들도 무집단의 세대가 변화함에 따라 과거와 달리 새로운 학습적인 요소들이 첨가된 것에 대해 인정하고 수용하는 입장을 취하고 있다. 마을단위에서도 전통적인 굿의 형식이나 제의만을 주장하기보다 마을 주민 모두가 함께 어우러질 수 있는 축제 형식이나 다양한 굿의 방향성을 고민하고 있다. 변화하는 굿의 흐름과 신진 세대의 적응에서 새로운 의미를 찾아나가고 있는 것이다. 급변하는 시대의 흐름에 따라 굿판이 점점 축소되는 현실 속에서 동해안굿은 다른 지역 굿에 비해 아직까지는 활발히 연행되고 있다. 힘겹게 동해안굿을 보존해 온 세습무의 뒤를 이어 학습무들이 활발히 유입되고, 연행 집단이 굿의 전통을 보존하는 한편, 굿을 예술 콘텐츠로 활용하기 위해 애쓰고 있기 때문이다. 또한 학습무들은 세습무로부터 배워 온 무속의 학습을 체계적으로 정리하여 후대에 최대한 원형에 가깝게 전승하고자 준비하고 노력하고 있다. 앞으로도 동해안굿은 마지막 세습무의 대를 이어 학습무들이 전통을 계승하고 시대에 맞춰 발전시켜 나갈 것이다.

• 대한기계학회논문집B
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• 제30권9호
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• pp.858-865
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• 2006

SMART Pilot is a multipurpose small capacity integral type reactor. Main coolant pump (MCP) of SMART Pilot is a canned-motor-type axial pump to circulate the primary coolant between nuclear fuel and steam generator in the primary system. The reactor is designed to operate under condition of $310^{\circ}C$ and 14.7MPa. Thus MCP has to be tested under same operating condition as reactor design condition to verify its performance and safety. In present wort a test apparatus to simulate real operating situations of the reactor has been designed and constructed to test MCP. And then functional tests, performance tests, and endurance tests have been carried out upon a prototype MCP. Canned motor characteristics, homologous head/torque curves, coast-down curves, NPSH curves and lift-time performance variations were obtained from the qualification test as well as hydraulic performance characteristics of MCP.

• 한국자동차공학회논문집
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• 제11권4호
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• pp.211-219
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• 2003

The main study experiments to obtain engine torque of the vehicle during performance test of the recent automobile. Torque was measured through the engine dynamometer to produces engine torque of the vehicle but the research method calculated engine torque of the vehicle without the engine dynamometer. The performance of the vehicle receive various running resistance. The study certificates performance of certification before a certification of used vehicle didn't carry out and certificate. This way evaluated on road test and chassis dynamometer The result of the study shows that it is much possible to apply the test. After comparing the engine torque of road driving with that of chassis dynamometer, the results are approximately the same. When rapidly speeded up, the road-load vehicle can pitch in some degrees, which may result in the fluctuations of acceleration, and then affect on the engine torque. Therefore it is confirmed that this method is easier way to measure the performance of vehicles.

• 한국농공학회논문집
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• 제62권2호
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• pp.75-82
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• 2020

The Daehang-ri intertidal flat located the just outside of the Saemangeum dike has been reported to show new-developing flats. Based on the topographic surveys of 21 times from 2000 to 2016 by a leveling method every year, this site clearly shows variation of deposition/erosion in time and space. Deposition has consistently occurred at the rate of +3.75 cm per year at the area along the dike (Zone 1), and this tidal flat is expanding and prograding seaward. In the area of far from the dike (Zone 2), on the other hand, erosion prevails at the rate of -2.38 cm per year, and this zone tends to retreat landward. However, the erosional trend of Zone 2 has slightly slowed down since 2014. As a whole from 2000 to 2016, net deposition is recorded over 3.0 m at the upper beach and the area adjacent to the dike (Zone 1), while erosion up to 1.0 m in Zone 2. In conclusion, the results at the Daehang-ri intertidal flat clearly revealed that its topographic changes were induced by the artificial structures and water masses through its sluice gate. Counter-clockwise gyre newly created after the sea dikes construction probably results in relocating of sediment outside the dike 1 by transportation of materials eroded from the south to the north along the coast.

• 한국자동차공학회논문집
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• 제21권4호
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• pp.153-158
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• 2013

The purpose of this study is to investigate the performance characteristics of the counterflow exhaust heat recovery device for the applied gasoline engines. The EHRS device is installed behind the catalyst. This study investigates the engine warm-up characteristic, the exhaust noise characteristic, the back-pressure characteristic. The engine warm-up characteristics is (load 0%, load 10%, load 20%) in (idle, 1000rpm, 1500rpm, 2000rpm, 2500rpm) conditions by measuring the time it warmed up, coolant temperature ($25^{\circ}C{\sim}80^{\circ}C$) until the performance evaluation is performed. The wide open throttle and the coast down the exhaust noise and the back-pressure characteristic experiment repeated twice. The test conditions is 950rpm~6,050rpm proceed experiment repeated 3-5 times. Load 0% idle conditions except the results improved engine warm-up characteristics. The exhaust noise obtain similar results the BASE+EHRS W/O_FRT_MUFF with BASE and back-pressure to obtain similar results BASE+EHRS W/O_FRT_ MUFF with BASE+EHRS.