• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.257-257
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• 2000

The objective of this research is to monitor and control the vehicle motion in order to remove out the existing safety risk based upon the human-machine cooperative vehicle control. A predictive control method is proposed to control the steering wheel of the vehicle to keep the lane. Desired angle of the steering wheel to control the vehicle motion could be calculated based upon vehicle dynamics, current and estimated pose of the vehicle every sample steps. The vehicle pose and the road curvature were calculated by geometrically fusing sensor data from camera image, tachometer and steering wheel encoder though the Perception Net, where not only the state variables, but also the corresponding uncertainties were propagated in forward and backward direction in such a way to satisfy the given constraint condition, maintain consistency, reduce the uncertainties, and guarantee robustness. A series of experiments was conducted to evaluate the control performance, in which a car Like robot was utilized to quit unwanted safety problem. As the results, the robot was keeping very well a given lane with arbitrary shape at moderate speed.

• IEIE Transactions on Smart Processing and Computing
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• 제3권3호
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• pp.135-141
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• 2014

The inherent feature of the highly efficient spectrum usage has made Orthogonal Frequency Division Multiplexing (OFDM) preferable for Communication Standards. This study evaluated the performance of a Least Square (LS) estimator for a comb-type pilot insertion scheme over a fast fading Rayleigh channel. A High Peak-to-Average Power Ratio (PAPR) is one of the major downsides of the OFDM. The effects of an increase in the number of subcarriers on PAPR and the performance of the LS Estimator were studied. Increasing the number of subcarriers while keeping the pilots overhead constant resulted in improved performance of the LS estimator but the PAPR increased with increasing number of subcarriers. Therefore some trade-off between the number of subcarriers and the performance of the OFDM system is needed. The Mean Square Error (MSE) expression was also derived for the LS estimator in the case of a comb-type pilot arrangement. The MSE expression clearly explains the effects of the number of subcarriers on the performance of the LS estimator.

• 한국건축시공학회지
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• 제8권6호
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• pp.117-122
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• 2008

This study targets to improve and complement the problem of existing flame resistant processing with flame resistant performance the same as existing flame resistant agents or better, keeping wooden surface & feel as they are, and to attempt to raise flame resistant performance and economic efficiency by applying phosphorous flame resistant agents, a colorlessness, odorless new product to woods for an improvement of flame resistant performance for wooden nature and to offer a basic data for an uniform high-performance for flame resistant woods by reinforcing wooden durability and usability.

• 한국생산제조학회지
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• 제8권5호
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• pp.108-114
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• 1999

The thermal environmental chamber has been using in maintaining weather condition keeping thermal capacity under heating and cooling load fluctuation and for the performance testing of cooling system or air-conditioner on artificial envi-ronment. In ordder to make the various environmental conditions in the thermal environmental chamber the proper cooling system is necessary to eliminate the heating load produced inside the chamber and to maintain the designed environmental condition. For this reason the optimal design of cooling system and the prediction of performance is also required. This paper describes the prediction of performance of cooling system in the thermal environmental chamber with the capacity of 37,000kcal/hr which is developed for the test of performance in heating mode of heat pump system, In the results this paper is trying to develop simulation program on the base of mathematical models and which can be applied effectively to the optimal design of cooling system and prediction of performance to the inside and outside change of envi-ronmetal load.

• 한국정밀공학회지
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• 제21권2호
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• pp.92-99
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• 2004

The errors can cause the serious loss of the performance of a precision machine system. In this paper, we proposed the method of allocating the alignment tolerances of the parts and applied this method to get the optimal tolerances of a Confocal Scanning Microscope. In general, tight tolerances are required to maintain the performance of a system, but a high cost of manufacturing and assembling is required to preserve the tight tolerances. The purpose of allocating the optimal tolerances is minimizing the cost while keeping the high performance of the system. In the optimal problem, we maximized the tolerances while maintaining the performance requirements. The Monte Carlo Method, a statistical simulation method, is used in tolerance analysis. Alignment tolerances of optical components of the confocal scanning microscope are optimized to minimize the cost and to maintain the observation performance of the microscope. We can also apply this method to the other precision machine system.

• 여성건강간호학회지
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• 제8권4호
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• pp.506-520
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• 2002

The purpose of this study is to research the degree of recognition & performance of traditional postpartal care for postpartal women and to provide the basic data for improvement of service in a postpartum care center. The respondents of this study were 100 women of 6 postpartum care centers within a C province from Oct. 20 to Dec. 10, 2000. The instruments of measure were used for collecting data on the degree of recognition & performance of traditional postpartal care developed by the researcher. Data analysis consisted of frequency, percentage, mean, standard deviation, paired t-test, t-test, ANOVA which are calculated by Scheffe test and Cronbach's alpha which is used as a reliance level by using a SPSS-PC+. The results of the study were as follows:1. The average score for the degree of recognition of traditional postpartal care(Sanhujori) for postpartal women was $3.09{\pm}.31$, and they recognized that it was important. The methods which were ranked were as follows; Protecting the body from a harmful state, invigorating the body by the argumentation of heat and avoidance of cold, handling with whole heart, and keeping clean, resting without working, eating well. 2. The average score for the degree of performance of traditional postpartal care (Sanhujori) for postpartal women was $2.81{\pm}.31$, and they performed that it was important, too. The methods which were ranked were as follows; Protecting the body from a harmful state, invigorating the body by the augumentation of heat and avoidance of cold, eating well, handling with whole heart, and keeping clean, resting without working. 3. There were significant differences statistically (paired-t=-8.39, p=.000) of the degree of recognition & performance of traditional postpartal care(Sanhujori) for the postpartal women. The degree of recognition was higher than the degree of performance. So, the recognition of traditional postpartal care (Sanhujori) was higher than the performance of it. 4. There were no statistical differences of the degree of recognition & performance of traditional postpartal care(Sanhujori) among the postpartal women's age, religion, job, educational background, delivery frequency, delivery method or the sex of baby. So, the Characteristics of the respondents were not influenced as far as the degree of recognition & performance of traditional postpartal care(Sanhujori). 5. There were significant differences statistically of the degree of performance of traditional postpartal care(Sanhujori) among the 5 postpartum care centers except 1 postpartum care center(p<.01). So, the recognition of traditional postpartal care(Sanhujori) was higher than the performance of traditional postpartal care(Sanhujori) in the 5 postpartum care centers. But there was performed as good as recognition in only 1 postpartum care center.

• 한국생활과학회지
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• 제19권4호
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• pp.667-674
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• 2010

This study evaluated the convenience and heating performance of 4 heated vests on the market through a trial of the vests. Participants were four healthy men who wore the garments outside in cold temperatures typical of the garments' real conditions of use. As the results, all the participants preferred the product, having an easily operable controller in ergonomic aspects and the good insulation for keeping the body temperature. The heating performance of vests was the most important factor in selecting the best product in this test. Indeed, the vests themselves found not to be sufficiently warm in the experimental condition. Thus, heated vests with the enhanced heating performance should be developed so that temperatures in the allowed range can be safely accessed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.223-228
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• 2009

Cooling and heating equipments of railroad passenger cabin is one of the most important part in keeping the good thermal comfort of the passengers. The bad performance of these equipments usually results in the comfort of the passengers. However, there is no testing method for cooling and heating equipments during manufacturing the passenger car, and calculation method is frequently used. Many railroad operators spend a lot of money for the maintenance. In this study, a new environmental performance test for railroad passenger cabin was suggested. The temperature of the chamber will be changed from $-40^{\circ}C$ to $60^{\circ}C$. The performance test of cooling and heating equipment in controlling the passenger cabin temperature was carried out under various temperature condition. The testing method to investigate the effect of artificial sunlight irradiation on the passenger cabin temperature was also suggested.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.805-810
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• 2005

The main functions of suspension system of railway vehicle are isolating vibration from track irregularity to car-body for the Ride quality and keeping its stability with limitation of vehicle's movement. These two functions conflict with each other, then it is impossible to achieve both of performance with traditional passive suspension which has constant characteristics. So, to improve this situation the active suspension was suggested and in specially the semi-active suspension is noticed for its effectiveness on cost despite of its lower performance than full-active suspension. In this study the control logic made through LQG theory was designed with simplified vehicle model and variable damper model defined by $1^{st}$ order system, then the analysis of simulation results was done to understand influence on the performance of semi-active suspension with running conditions and response characteristics of variable damper.

• 한국산학기술학회논문지
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• 제21권7호
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• pp.590-596
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• 2020

군용 방한복 상의 내피 원단은 원단과 패드타입 솜을 누빔(퀼팅)하는 형태로 제조되어 보온성을 부여하고 있다. 이렇게 제조된 방한복 내피 원단을 퀼팅원단이라고 하는데, 퀼팅원단은 윗실, 밑실이 각각 교차하여 원단과 솜을 같이 봉제하는 형태로 견고하게 제조되는 것이 일반적이다. 따라서 제조된 퀼팅원단에서 원단과 솜을 분리하는 것은 거의 불가능하며, 이를 분리할 경우 원단 및 솜에 상당한 손실을 가져올 수 있다. 본 연구에서는 퀼팅원단을 제조한 뒤 원단을 손상시키지 않고 후속가공을 통해 보온력을 증대시키고 두께 변화율을 안정화 시키는 방법에 대해서 연구하였다. 일반적인 솜 생산 시설 중 일부 설비를 이용하여 퀼팅원단을 통과시키는 비교적 간단한 방법을 통해 연구를 수행하였고 다음과 같은 결과를 얻을 수 있었다. 보온성의 경우 후속가공하기 전 퀼팅원단에 비해 clo값 기준으로 약 10 %가 상승한 효과가 나타났으며, 세탁 두께 변화율은 후속가공하기 전 퀼팅원단에 비해 약 10 % p. 안정화된 효과를 보여주었다. 이는 퀼팅원단 제작 후에도 후속가공을 통해 보온성을 향상시키고 세탁에 따른 두께 변화율을 안정화 시킬 수 있음을 나타낸다.