• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.167-174
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• 2006

Two typical responses have been documented for flatfish when they encounter the ground gear of bottom trawls: herding response and falling back response. These two responses were analyzed from video recordings of fish and were characterized by time sequences for four parameters: swimming speed, angular velocity, acceleration, and distance between the fish and the ground gear. When flatfish displayed the falling-back response, absolute values of the three swimming parameters and their deviations were significantly higher than those during the herding response. However, the swimming parameters were not dependent on the distance between the flatfish and the ground gear, regardless of which response occurred. The dominant periods for most of the movement parameters ranged from 2.0 to 3.7 s, except that no periodicity was observed for swimming speed or angular velocity during the falling-back response. However, variations in the four parameters during the falling -back response revealed greater irregularity in periodicity and higher amplitudes. This complex behavior is best described as a chaos phenomenon' and is discussed as the building block for a model predicting the responses of flatfish to ground gear as part of the general understanding of the fish capture process.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.113-116
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• 2008

In this paper we suggest two novel methods for an implementation of the spot detection phase in the 2-DE gel image analysis program. The one is the adaptive thresholding method for eliminating noises and the other is the asymmetric diffusion model for spot matching. Remained noises after the preprocessing phase cause the over-segmentation problem by the next segmentation phase. To identify and exclude the over-segmented background regions, il we use a fixed thresholding method that is choosing an intensity value for the threshold, the spots that are invisible by one's human eyes but mean very small amount proteins which have important role in the biological samples could be eliminated. Accordingly we suggest the adaptive thresholding method which comes from an idea that is got on statistical analysis for the prominences of the peaks. There are the Gaussian model and the diffusion model for the spot shape model. The diffusion model is the closer to the real spot shapes than the Gaussian model, but spots have very various and irregular shapes and especially asymmetric formation in x-coordinate and y-coordinate. The reason for irregularity of spot shape is that spots could not be diffused perfectly across gel medium because of the characteristics of 2-DE process. Accordingly we suggest the asymmetric diffusion model for modeling spot shapes. In this paper we present a brief explanation ol the two methods and experimental results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1995년도 연약지반 안정처리 시공.관리 세미나
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• pp.15-34
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• 1995

연약지반상 성토에 따른 지반의 변형은 성토제체의 안정성에 큰 영향을 미친다. 따라서, 지반의 여러가지 특성에 따른 거동에 대해 살펴보았으며, 이는 복합적인 요인을 가진 성토제체 안정상 분석의 기초자료로 삼을 수 있으리라 본다. 그리고, 이러한 영향에 대해 국내의 현장 계측결과와 외국사례의 경우를 비교하였다. 한편, 기존의 안정성 분석 방법에 대하여 국내의 현장 적용에 있어 몇가지 문제점들을 국내의 사레와 비교.검토하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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• pp.136-139
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• 2003

Thermal imaging system is electro-optical imaging device which can make visible the difference of infrared energy naturally emitted by objects. It is acquire the same images at any time of the day or night. There it has been readily available to the night observation such as fire control systems. In this study, we are manufacturing thermal image Al flat mirror. The surface roughness 3.539nm Ra and power 0.382 fringe(at 632.8nm), irregularity 0.835 fringe(at 632.8nm) for form waviness of thermal image Al flat mirror are very satisfied. The results will be reflected for development of the ultra precision application. And a brief review of Ultra-precision system in the field of Ultra-precision at Korea photonics technology institute (KOPTI) is present in this paper.

• Transactions on Electrical and Electronic Materials
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• 제11권2호
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• pp.49-53
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• 2010

Microstructural origins of leakage current and physical degradation during operation in product-quality AlGaN/GaN high electron mobility transistor (HEMT) devices were investigated using photon emission microscopy (PEM) and transmission electron microscopy (TEM). AlGaN/GaN HEMTs were fabricated with metal organic chemical vapor deposition on semi-insulating SiC substrates. Photon emission irregularity, which is indicative of gate leakage current, was measured by PEM. Site specific TEM analysis assisted by a focused ion beam revealed the presence of threading dislocations in the channel below the gate at the position showing strong photon emissions. Observation of electrically degraded devices after life tests revealed crack/pit shaped defects next to the drain in the top AlGaN layer. The morphology of the defects was three-dimensionally investigated via electron tomography.

• 한국지능시스템학회논문지
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• 제15권3호
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• pp.330-336
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• 2005

이동로봇의 주행을 위한 초음파 센서 만에 의한 기존의 베이지안 지도 작성법은 초음파 센서 빔의 퍼짐 특성 등에 의해 굴곡이 많은 환경의 경우 양질의 지도가 형성되지 못한다. 이러한 문제의 개선을 위해 본 논문에서는 적외선 센서를 설치하여 초음파 센서 빔의 각 영역에서의 장애물에 대한 정보를 획득하고, 이 정보를 이용 퍼지 추론시스템에 의하여 초음파 센서에 의한 정보의 신뢰도를 구하여 베이지안 지도 작성법에 의한 결과에 융합시킴으로써 보다 정확한 환경 지도를 작성하는 방법을 제시하였다. 또한, 퍼지 추론 시스템을 최적화하기 위하여 유전 알고리즘을 사용하였다. 그리고 시뮬레이션 및 실제 실험에 의해 제안된 방법이 굴곡이 많은 환경의 경우 기존의 방법 보다 정확한 지도 작성이 가능함을 검증하였다.

• 동아시아식생활학회지
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• 제20권3호
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• pp.352-362
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• 2010

This study was conducted to investigate the influence of obesity stress on the eating behavior of elementary school students. Using a questionnaire, 300 students in the sixth grade from 2 schools in Kyunggi-do were surveyed (Boys: N=145, Girls: N=155). Data analysis was managed by SPSS software (version 13.0). The link between obesity stress and eating habits or behaviors was dependent on physical discomfort. There was also a large group of students experienced irregularity in their meal times during the day. Furthermore, there were significant differences in mealtime among boys under psychic stress caused by obesity. In the case of dairy intake during breakfast, the significant signs of obesity stress for were physical discomfort for boys and psychic stress for the girls. It was found for both boys and girls that more frequent midnight snacking decreased the efforts to overcome obesity stress. Therefore, a professional nutrition program that can educate school children must be implemented both in school and at home. In addition to overweight or obesity children, normal weight and underweight children can also benefit from this program that includes health counseling for weight and eating behaviors.

• 한국농공학회논문집
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• 제57권1호
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• pp.1-9
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• 2015

In this study it was adopted on sea dike monitoring that the safety monitoring with statistical limits which was adapted usually on safety monitoring by measuring pressures, stresses or deformations. And also the hydraulic head loss rate change according to passage of time was calculated for the purpose of safety monitoring. Safety monitoring by setting the statistical limit on the measured pore water pressure graphs need to be supplemented with an additional method of monitoring because the difference between the rise and fall of the tide was irregular. Safety monitoring by the limits set from values predicted by linear regression and standard errors on the hydraulic head loss graph was not affected by irregularity of tide. But if the condition of an embankment is changed gradually and slowly, it will not be detected on the hydraulic head loss graph. The graph of hydraulic head loss rate for every 24 hours vs date showed clearly that the sea water blocking state was getting better or not even though it was changed gradually and slowly.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.348-356
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• 2004

In this paper, Analysis of parameters effecting on the derailment factor was conducted in oder to deduce technical requisites have to be reflected in design of Track and rolling-stocks because it is important to grasp the risk of derailment quantitatively. And then go far toward becoming practical study with that select two section of sharp curved track of actual train in service, incheon Metro Line 1 and make field research in condition of vehicles and track and analysis As a result of parameter study, the following conclusions were obtained. The radius of curve and Cant is in inverse proportion to the derailment factor, but as train operation velocity, standard deviation of alignment irregularity and the ratio lateral force : wheel load of the inside track increase, the derailment factor rise. In the investigation for the derailment safety of incheon Metro Line 1, the derailment factor was below 0.43 in both section R=200 and R=300, so that it proved safe compare with allowance limits 0.8, but it appeared that risk of the derailment in second transition curve is the highest among the entire curve.

• International Journal of Railway
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• 제4권4호
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• pp.93-96
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• 2011

The basic element of the EMS suspension is the electromagnet system, which suspends the vehicle without contact by attracting forces to the rails at the guideway. The suspension of a vehicle by attractive magnetic forces is inherently unstable and consequently it is continuously adjusted by the strength of the suspending electromagnet from rail irregularity and bending of the guideway. In order to improve reliable tracking, it needs to get feedback signals without measurement delay time. In this paper the concept of feedback control system with Kalman Filter in EMS is proposed. The input signals in the feedback control system are an air-gap and an acceleration signal. The air-gap signal with noise from the gap sensor is transformed to the filtered air-gap signal y without measurement delay time by using Kalman Filter. The filtered air-gap signal is transformed to a relative velocity and a relative acceleration signal. Then it multiplies these values by gain matrix in order to get the actuator's reference voltage value. The simulation results show that the dynamic responses of the suspension system can be improved by reducing the influence of measurement delay time of air-gap signals.