• 가정과삶의질연구
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• 제20권3호
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• pp.139-156
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• 2002

The purpose of this study is to compare the patterns of time use between Korean and USA families. The data for 353 Seoul-based Korean families with two children living in Seoul and 130 USA families with two children living in the State of Utah were collected using a structured questionnaire and time diary. The major findings were as the following: 1. The Korean couples spent more time at personal care, paid work, and travel than the USA couples did, while the USA couples spent more time at housework and social-cultural activities than the Korean couples did. 2. The Korean wives spent more time doing food and clothing related housework than the USA wives did. Compared with the Korean wives, however, the time spent at house cleaning and management, family care and shopping and home management were longer than USA wives. The time U.S. husbands engaged in housework was much greater than by the Korean husbands. 3. Regardless of sex and school level, the Korean children spent less time at sleeping/rest, housework and socio-cultural activities and more time at eating and learning than those of U.S. These time use patterns of the families in both countries may reflect the differences of the cultural contexts, social norms, life styles, and the degrees of urbanization. To fully explain the findings, further study on the differences in social and cultural factors between the two countries is needed.

• 한국도로학회논문집
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• 제14권4호
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• pp.163-173
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• 2012

PURPOSES : The purpose of this study is to check the possibilities of traffic pattern analysis using MatSIM for urban road network operation in incident case. METHODS : One of the stochastic dynamic models is MatSIM. MatSIM is a transportation simulation tool based on stochastic dynamic model and activity based model. It is an open source software developed by IVT, ETH zurich, Switzerland. In MatSIM, various scenario comparison analyses are possible and analyses results are expressed using the visualizer which shows individual vehicle movements and traffic patterns. In this study, trip distribution in 24-hour, traffic volume, and travel speed using MatSIM are similar to those of measured values. Therefore, results of MatSIM are reasonable comparing with measured values. Traffic patterns are changed according to incident from change of individual behavior. RESULTS : The simulation results and the actual measured values are similar. The simulation results show reasonable ranges which can be used for traffic pattern analysis. CONCLUSIONS : The change of traffic pattern including trip distribution, traffic volumes and speeds according to various incident scenarios can be used for traffic control policy decision to provide effective operation of urban road network.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.792-795
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• 1996

In TIG welding of pipe, back bead size monitoring is important for weld quality assurance. Many researches have been performed on estimation of the back bead size by heat conduction analysis. However numerical conduction model based on many uncertain thermal parameters causes remarkable errors and thermomechanical phenomena in molten pool can not be considered. In this paper, filler wire feeding force in addition to weld current, wire feedrate, torch travel speed and orbital position angle is monitored to estimate back bead size in orbital TIG welding. Monitored welding process variables are fed into an artificial neural network estimator which has been trained with the monitored process variables (input patterns) and actual back bead size (output patterns). Experimental verification of the proposed estimation method was performed. The predicted results are in a good agreement with the actual back bead shape. The results are quite promising in that estimation of invisible back bead shape can be achieved by analyzing the welding parameters without any conventional NDT of welds.

• 농업과학연구
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• 제40권1호
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• pp.53-59
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• 2013

Analysis of load data during field operations is highly important for optimum design of power drive lines for agricultural tractor. Objective of the paper was to analyze field load data using FFT to determine frequency and the energy levels of meaningful cyclic patterns. Rotary tillage, plowing, baling, and wrapping operations were selected as major field operations of agricultural tractor. An agricultural tractor with power measurement system was used. The tractor was equipped with strain-gauge sensors to measure torque of four driving axles and a PTO axle, speed sensors to measure rotational speed of the driving axles and an engine shaft, pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to calculate power requirement. In rotary tillage, calculated frequency was decreased as travel speed increased. In baler operation, calculated frequency was increased as PTO speed was increased. The calculated peak frequency levels and expected levels were similar. Results of the study would provide information on power utilization patterns and on better design of power drive lines.

• Journal of Ecology and Environment
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• 제43권1호
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• pp.1-8
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• 2019

Background: Hibernating bats exhibit ubiquitous winter activity in temperate zones, but there is considerable between- and within-species variety in their intensity and purpose. Bats may fly during winter for sustenance or travel to other hibernacula. This study compared inter-regional variation in the winter activity of the greater horseshoe bat (Rhinolophus ferrumequinum). We predicted that weather and hibernacula-environmental conditions would influence winter activity patterns. Results: Winter activity patterns differed between regions. In the Anseong area, we confirmed movement inside the hibernaculum, but in Hampyeong, we observed movement both inside and between hibernacula. The two regions differ by $4^{\circ}C$ in average winter temperatures. Anseong experiences 22 days during which average daily temperatures exceeded $5^{\circ}C$, whereas Hampyeong experienced 50 such days. During the hibernating period, bat body weight decreased by approximately 17-20% in both regions. Conclusions: Ambient temperatures and winter-roost environments appear to be behind regional differences in hibernating bat activity. As winter temperatures in Korea do not favor insect activity, feeding probability is low for bats. However, bats may need to access water. At Anseong, underground water flows inside the hibernaculum when the reservoir outside is frozen. At Hampyeong, the hibernaculum does not contain a water source, but the reservoir outside does not freeze during winter. In conclusion, water-source location is the most likely explanation for regional variation in the winter activity of hibernating bats.

• 영어어문교육
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• 제4호
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• pp.229-247
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• 1998

Keats is a poet who was in pursuit of 'the beautiful'. He tried to show various structures in his poetry to search for 'eternal pleasure'. These are explained in terms of 'metamorphosis', 'travel structure' and 'metamorphosis patterns', but put together, these can be expressed as simple terms of a dramatic structure. Especially We can assume this dramatic structure is the key to access his poetry on the basis of the fact that Keats always admired the world of drama and respected Shakespeare most. We can see Keats' dramatic structure in his poetry Ode to a Nightingale, Ode on a Grecian Urn. To Autumn and so on, and in these three poems, he was very successful in achieving unique poetic expression by inducing tension structure' through the dramatic structure of Introduction - development - crisis - climax - ending. In conclusion, his poetry achieved success in that he made clear his central theme, the pursuit of a beautiful and happy life through the application of a dramatic structure.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.1084-1092
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• 2005

Various urban transport policies have an effect on urban transit riderships. This study reports variations of metropolitan subway travel patterns affected by an enormous change in bus routes and transfer discount policy between subway and bus mode conducted by Seoul city in July 1st of 2004. In an effort to see the difference between the before and the after policies, two datasets are prepared. Firstly, on a daily bassis, an origin-destination trip table of May of 2004 is used. Secondly, on a daily bassis, an origin-destination trip table of August-September of 2004 is used as a counter measure. Even if seasonal variation was not considered. there were increasing riderships of about 0.25 million on a daily basis. Subway line 2 and 7 have an important role in changes. The effects or system changes, however. largely varied on location and subway line numbers.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제13권2호
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• pp.116-123
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• 2013

Currently, most automobiles have automatic transmission systems. The gear-shifting strategy used to generate shift patterns in transmission systems plays an important role in improving the performance of vehicles. However, conventional transmission systems have a fixed type of shift map, so it may not be enough to provide an efficient gear-shifting pattern to satisfy the demands of driver. In this study, we developed an intelligent strategy to handle these problems. This approach is based on a normalized radial basis function neural network, which can generate a flexible gear-shift pattern to satisfy the demands of drivers, including comfortable travel and fuel consumption. The method was verified through simulations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 춘계학술대회 논문집
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• pp.383-388
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• 1995

The ARC light has been measured using photo-detect system under different TIG welding condition. Light detect system consists of photo diode, ND Filter, OP Amp. A/D convertor and PC. The purpose of this experiment is to show the relationship between ARC light and process variables such as welding current, torch travel speed, etc. The results can be applied to estimate the condition of welding process and the quality of welding products. The signal of ARC light has periodic patterns in good TIG welding condition whereas in abnormal condition the signal has different pattern. Amount of Ar shielding gas and distance from electrode to specimen affect the signal pattern significantly.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 추계학술발표대회
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• pp.10-13
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• 2010

컴퓨터의 활용이 다양해 지면서 예전과 다르게 다양한 이유로 많은 사람들이 여행을 하고 나서 여행에 대한 정보 블로그나 웹 상에 저장하고 공개한다. 이렇게 웹 상에 많은 양의 여행 관련 데이터가 존재함에도 불구하고 데이터들이 산발적으로 존재하고 체계적으로 데이터 베이스화 되어 있지 않아서 여전히 정보를 검색하고 여행 일정을 세우는 데에 많은 시간과 노력이 필요하다. 따라서 본 논문은 FP-tree 기반의 빈발 패턴 증가 기법을 이용한 여행 계획 수립 기법을 제안한다. 제안되는 기법에서 데이터들은 FP-tree 방식으로 저장되어 검색에 필요한 시간과 노력을 극적으로 줄이고, FP-growth 마이닝 기법을 이용해 효과적인 여행 경로를 선택할 수 있게 도와준다.