다중 미세유로를 갖는 납작관을 사용한 음축기의 열성능 ( Thermal Performance of Condenser Using Flat Tube with Multi-Channel )

유성연,이기성,이상윤,김등진,한창섭,조영두 대한기계학회 1997 대한기계학회 춘추학술대회 Vol.- No.-

연구정보 : 무인원격 탐사정 ( AUV ) 개발

유성연 대한기계학회 1998 기계저널 Vol.38 No.5

직각 밀폐용기 내에서 자연대류 열전달의 가시화 ( Visualization of Natural Convection Heat Transfer in a Rectangular Enclosure )

유성연,김승모,서항석 대한기계학회 1994 대한기계학회 춘추학술대회 Vol.- No.-

냉방부하 추정을 위한 온도와 습도 예측에 관한 연구

유성연,이제묘,한규현,한승호 대한설비공학회 2007 설비공학 논문집 Vol.19 No.5

To estimate the cooling load for the following day, outdoor temperature and humidity are needed in hourly base. But the meteorological administration forecasts only maximum and minimum temperature. New methodology is proposed for predicting hourly outdoor temperature and humidity by using the forecasted maximum and minimum temperature. The correlations for normalized outdoor temperature and specific humidity has been derived from the weather data for five years from 2001 to 2005 at Seoul, Daejeon and Pusan. The correlations for normalized temperature are independent of date, while the correlations for specific humidity are linearly dependent on date. The predicted results show fairly good agreement with the measured data. The prediction program is also developed for hourly outdoor dry bulb temperature, specific humidity, dew point, relative humidity, enthalpy and specific volume.

嘉納治五郞 유도 문화의 본질

유성연,김유수 한국사회체육학회 2007 한국사회체육학회지 Vol.0 No.29

President of the Tokyo University of Education, the 1st IOC member in Asia, the founder of the Japan Sports Association, and a member of the House of Peers. Kano Jigoro was, in short, a forerunner in the modernization process of Japan. He was a giant who had an enormous effect on the circles of education and politics as well as on the birth of judo. Nonetheless, we tend to focus on his judo philosophy only, possibly because he was a great judo expert and because he frequently used the term judo whenever he mentioned sports and human relations. In other words, Kano's judo meant more than a martial art or a sport event. That's why his philosophy has not been rightly understood or misunderstood up to now and why we need to know what is correctly meant in his common use of the term judo. This study of his judo culture based on this viewpoint revealed the following results: 1. As the initiator of judo at Kodokan he built, Kano began to teach judo in 1882. He defined judo as the "method to use the power of body and mind most effectively" in 1915 when his philosophy was mature. He also emphasized, "The essence of this sport can be felt by physical training and mental practice through the repetition of offense and defense. The ultimate goal of judo practice is to complete oneself and profit the world." After establishing the Kodokan Cultural Association in 1922 when his ideology was perfect, he stressed two judo-application principles of social life: using power rightly and benefiting others and myself. This maturity of Kano's philosophy came to affect other Japanese martial arts like kendo. 2. Judo is the academic perfection of conventional jyujyutu, taking the good and discarding the bad to fit today's society. He chose a new name judo to escape from the harsh criticism of jyujyutu by the general public. So Kodokan's judo was born to compliment the achievement of ancestors, get rid of prejudices and misunderstanding about jyujyutu, and modernize it technically. 3. According to Kano, judo at Kodokan has three purposes: physical education, victory, and mental practice. The first two objectives are related with traditional jyujyutu. The third item includes cultivating virtue, training mentality, and practicing the ways to deal with every different case.

한국 유도 기원설의 변화과정 연구

유성연 대한무도학회 2023 대한무도학회지 Vol.25 No.2

이 연구는 대한제국부터 해방 직후까지 한국 유도 기원설의 변화과정을 심도 있게 고찰하여 한국적유도 사상이 정착되는 과정에 대해 밝히고자 한다. 첫째, YMCA유도반 초대 사범이었던 나수영은 신라의 유술인 천풍해세류가 일본으로 건너가 유도가 되었다고 주장하였다. 그의 이러한 주장은 제자들에 의해 구전으로 전파되어 한국 유도 기원설의 시발점이 된다. 둘째, 민족주의 사학자들은 유도는 고려시대의유술인 수박(手搏)이 일본으로 건너가 완성된 것이라 주장하였다. 이러한 주장들이 해방 직후 융합되어한국 유도 이식설의 배경이 된다. 셋째, 해방 직후 일제의 잔재를 청산하는 과정에서 유도인들은 무예도보통지에 나와 있는 신법(身法), 수법(手法), 각법(脚法)이 일본에 이식되어 손기술, 발기술, 허리기술로발전되었다는 구체적 주장을 하게 된다. 이상과 같이 한국 유도 기원설은 민족주의 사학자들의 역사 인식에 영향을 받았으며 여기에 경기 유도인들이 민족주의적 내셔널리즘 바탕으로 유도 기술을 문화 변용하여 한국적 유도 사상을 완성 시켰다.

열전소자 및 열전냉각장치의 성능에 관한 연구

유성연,홍정표,심우섭 대한설비공학회 2004 설비공학 논문집 Vol.16 No.1

Thermoelectric module is a device that can produce cooling in a direct manner using the electrical energy. The purpose of this study is to investigate the performance of thermoelectric module and cooling system equipped with the thermoelectric module. The performance of a thermoelectric module is estimated using two methods; theoretical analysis based on one-dimensional energy equations and experimental tests using heat source, heat sink and brass conduction extenders. For the thermoelectric cooling system, the temperatures in the chamber are recorded and then compared with those of lumped system analysis. The results show that the cooling capacity and COP of the thermoelectric module increases as the temperature difference between hot and cold surface decreases, and there is particular current at which cooling capacity reaches its maximum value. The experimental results for the thermoelectric cooling system are similar to those of lumped system analysis.

소닉노즐의 유출계수에 영향을 미치는 인자에 관한 연구

유성연,이상윤,박경암,Yu, Seong-Yeon,Lee, Sang-Yun,Park, Gyeong-Am 대한기계학회 1996 大韓機械學會論文集B Vol.20 No.12

Accuracy of gas flow measurements using sonic nozzle and factors which influence on the discharge coefficients of sonic nozzle are investigated with high pressure gas flow standard measurement system. The gas flow measurement system comprises two compressors, storage tank, temperature control loop, sonic nozzle test section, weighing tank, gyroscopic scale and data acquisition system. The experiments are performed at various nozzle throat diameter and inlet pressure. Overall uncertainty of discharge coefficients is estimated to less than .+-.0.2% and most of experimental data fall into this range. Dependence of discharge coefficients on the Reynolds number is good agreement with those suggested in ISO document. The influence of swirl on the discharge coefficients becomes greater as the nozzle throat diameter is enlarged. The discharge coefficient of conical nozzle shows about 4.5% lower discharge coefficients than those of toroidal nozzle, but variation trend with Reynolds number is very similar each other and reproducibility of data is very good.

열전자소자의 냉각성능에 관한 연구 ( A Study on the Cooling Performance of Thermoelectric Module )

유성연,주병주,감정헌,이상윤,김광영 대한기계학회 1995 대한기계학회 춘추학술대회 Vol.- No.-

강화도 논에서 저어새(Platalea minor)의 섭식행동

유성연,권인기,유정칠 한국환경생태학회 2019 한국환경생태학회지 Vol.33 No.2

This study was conducted to examine the impact of various environmental factors on the feeding behavior of black-faced spoonbills Platalea minor known to use rice fields during the breeding season. We surveyed the rice fields three times a month from April to June 2017 and from April to June 2018. We counted the number of black-faced spoonbills and measured the environmental factors such as the water depth, paddy type by cultivation stage, and biomass of potential prey that are expected to affect black-faced spoonbills. We also filmed the feeding behavior of black-faced spoonbills to examine differences in feeding behavior by environmental factors. The survey showed that the number of black-faced spoonbills reached its peak from late April to late May which was the breeding period. Among a total of 308 black-faced spoonbills observed, 86.4% (n=266) were observed feeding on rice paddies, 90.6% (n=279) were adults, and none was observed on dry paddies. The biomass of rice paddy increased significantly since May when fish started hatching, and there was a significant difference in the amount of biomass between the rice paddies where black-faced spoonbills were observed and other rice paddies. The analysis of the feeding behavior of black-faced spoonbills showed that the feeding efficiency and feeding success rate of black-faced spoonbills increased significantly when the amount of biomass soared and that the number of steps of black-faced spoonbills per minute increased greatly after rice planting was completed. The number of bill sweeping was not related to the feeding efficiency, feeding success rate, and paddy type by cultivation stage. 본 연구는 번식기에 논을 이용하는 저어새의 섭식행동에 논의 다양한 환경요소가 어떤 영향을 주는지 알아보고자실시되었다. 2017년 4월부터 6월, 2018년 4월부터 6월까지 한 달에 3회씩 강화도 논을 대상으로 저어새의 개체수를조사하였다. 저어새가 영향을 받을 것으로 예상되는 환경요소로 수심, 경작에 따른 논의 구조적 형태, 잠재먹이원의생물량을 선정하여 측정하였고, 논의 환경에 따른 저어새의 섭식행동의 차이를 알아보기 위하여 관찰된 섭식행동을촬영하였다. 조사결과 저어새는 번식기간 중 4월 말부터 5월 말까지 논에 가장 많은 수가 도래했다. 총 308마리의개체 중 86.4%(n=266)가 섭식행동을 하고 있었고 90.6%(n=279)가 성조였으며, 물이 없는 논에서는 발견되지 않았다. 강화도 논의 생물량은 어류의 산란기가 시작되는 5월부터 크게 증가하였으며 저어새가 관찰된 논과 관찰되지 않은논의 생물량은 유의한 차이가 나타났다. 저어새의 섭식행동 분석 결과 논에 생물량이 많아지는 시기에 저어새의 섭식효율과 섭식성공률이 크게 증가하였고, 저어새의 분당 발걸음 수는 모내기를 한 논에서 크게 증가하였다. 분당 부리를젓는 횟수는 섭식효율 및 섭식성공률과 상관관계가 없었고, 논의 구조적 형태와도 관련이 없었다.