• 한국정보과학회논문지:소프트웨어및응용
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• 제28권12호
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• pp.947-954
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• 2001

본 논문에서는 인식된 얼굴의 포즈 상태 열에 오토마타 기법을 적용하여 다양한 헤드 제스처 를 인식하는 방법을 제안한다. 얼굴 영역의 추출에는 Yl7외 I성분인 최적의 얼굴색 정보와 적응적인 차영상 정보를 이용하며. 눈 영역 추출에는 소벨 연산자와 투영 기법. 그리고 눈의 기하학적 위치 정보를 이용 한다 얼굴의 상태 인식에는 계층적인 특징분석 방법을 사용하며, 인식된 얼굴 상태 열에 오토마타 기법을 적용하여 13가지 제스처; 준비, 상측, 하측, 좌측, 우측, 전진, 후퇴, 좌 윙크, 우 윙크, 좌 더블 윙크 우 더블 윙크, 긍정, 부정제스처를 인식한다. 총 8명으로부터 1,488 프레임의 영상을 취득하여 실험한 결과, 99.3%의 얼굴 영역 추출률 95.3%, 의 눈 영역 추출률, 94.1% 의 얼굴 상태 인식률. 그리고 93.3%의 헤드제 스처 인식률을 얻었다

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.255-261
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• 2005

본 연구에서는 수직블록배치형의 자동화 컨테이너 터미널을 대상으로 컨테이너 운반작업을 담당하는 2가지 유형의 이송장비인 무인이송차량(AGV)과 2단 적재차량(DSV)에 대한 이송능력을 분석하였다. AGV와 DSV의 주요 차이점은 안벽과 야드간의 컨테이너 운반시 적재용량이다. 기존의 자동화 터미널에 적용되고 있는 AGV은 20피트 컨테이너 2개 또는 40피트 컨테이너 1개의 적재용량을 가지지만, DSV는 20피트 컨테이너 4개 또는 40피트 컨테이너 2개를 동시에 적재할 수 있어 터미널 하역시스템의 효율성을 높일 수 있을 것으로 기대된다. 이에, 본 연구에서는 컨테이너 터미널의 이송장비 대한 처리능력을 분석할 수 있는 시뮬레이션 분석도구를 개발하여 이를 토대로 2가지 유형의 장비인 AGV와 DSV의 이송능력을 분석하였다. 본 연구의 결과로 실험대상 예제와 장비 생산성값이 제시되었다.

• Journal of Astronomy and Space Sciences
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• 제26권1호
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• pp.59-74
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• 2009

Relative navigation system is presented using GPS measurements from a single-channel global positioning system (GPS) simulator. The objective of this study is to provide the real-time inter-satellite relative positions as well as absolute positions for two formation flying satellites in low earth orbit. To improve the navigation performance, the absolute states are estimated using ion-free GRAPHIC (group and phase ionospheric correction) pseudo-ranges and the relative states are determined using double differential carrier-phase data and singled-differential C/A code data based on the extended Kalman filter and the unscented Kalman filter. Furthermore, pseudo-relative dynamic model and modified relative measurement model are developed. This modified EKF method prevents non-linearity of the measurement model from degrading precision by applying linearization about absolute navigation solutions not about the priori estimates. The LAMBDA method also has been used to improve the relative navigation performance by fixing ambiguities to integers for precise relative navigation. The software-based simulation has been performed and the steady state accuracies of 1 m and 6 mm ($1{\sigma}$ of 3-dimensional difference errors) are achieved for the absolute and relative navigation using EKF for a short baseline leader/follower formation. In addition, the navigation performances are compared for the EKF and the UKF for 10 hours simulation, and relative position errors are mm-level for the two filters showing the similar trends.

• Steel and Composite Structures
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• 제44권2호
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• pp.155-169
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• 2022

In the present paper an analytical model was developed to study the non-linear vibrations of Functionally Graded Carbon Nanotube (FG-CNT) reinforced doubly-curved shallow shells using the Multiple Scales Method (MSM). The nonlinear partial differential equations of motion are based on the FGM shallow shell hypothesis, the non-linear geometric Von-Karman relationships, and the Galerkin method to reduce the partial differential equations associated with simply supported boundary conditions. The novelty of the present model is the simultaneous prediction of the natural frequencies and their mode shapes versus different curvatures (cylindrical, spherical, conical, and plate) and the different types of FG-CNTs. In addition to combining the vibration analysis with optimization algorithms based on the genetic algorithm, a design optimization methode was developed to maximize the natural frequencies. By considering the expression of the non-dimensional frequency as an objective optimization function, a genetic algorithm program was developed by valuing the mechanical properties, the geometric properties and the FG-CNT configuration of shallow double curvature shells. The results obtained show that the curvature, the volume fraction and the types of NTC distribution have considerable effects on the variation of the Dimensionless Fundamental Linear Frequency (DFLF). The frequency response of the shallow shells of the FG-CNTRC showed two types of nonlinear hardening and softening which are strongly influenced by the change in the fundamental vibration mode. In GA optimization, the mechanical properties and geometric properties in the transverse direction, the volume fraction, and types of distribution of CNTs have a considerable effect on the fundamental frequencies of shallow double-curvature shells. Where the difference between optimized and not optimized DFLF can reach 13.26%.

• Journal of Chest Surgery
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• 제14권3호
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• pp.228-234
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• 1981

Measurement of cardiac output by thermodilution method is easy to perform and can be repeated at very short intervals and offers a number of theoretical and practical advantages. The purpose of this paper is to reevaluate the accuracy and reproducibility of the thermodilution cardiac output by comparing the results with those obtained by the direct Fick technique. From January through April 1981 [4 months], 26 simultaneous cardiac output measurements were made using thermodilution and direct Fick methods in 12 patients in the intensive care unit of Severance Hospital following open heart surgery. The average age of the patients was $34.8{\pm}12.0$ [SD] years [range; 17-57 years]. For cardiac output determination by thermodilution technique [$CO_TD$], a Swan-Ganz Thermodilution Catheter, Model 93A-131-7F [Edwards Laboratories], a Cardiac Output Computer, Model 9520A, and Strip Chart Recorder, Model 9810 [Edwards Laboratories] were used. For the determination of cardiac output by direct Fick principle [$CO_Fick$], a Van Slyke Manometric Apparatus [Thomas] for the measurements of arteriovenous oxygen content difference and a Collin`s Respirometer with Kymograph for the measurement of oxygen consumption were used. The correlation between the simultaneously measured $CO_TD$ and $CO_Fick$ was found to be $CO_Fick$ = 0.95.$CO_TD$ + 0.1073, [r= 0.9777, P < 0.001 ]. For 26 double or triple determinations of $CO_TD$, the values ranged from 1.77 L/min to 6.66 L/min, with a reproducibility of 2.18%. The maximum difference of $CO_TD$ for $CO_Fick$ was between +11.99% and -12,99% [$Mean{\pm}SD$ = $6.07{\pm}3.97$%]. Measurement of cardiac output by thermodilution method provides a simple, rapid, reproducible and highly accurate method for multiple cardiac output measurements suitable for use at the bedside. Comparison of Cardiac Output Determination by Direct Fick and Thermodilution Method in Man.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.772-775
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• 2006

Cinnamate polymers are well known photoreactive polymers due to [2+2] cycloaddition reaction of cinnamate side group. In this work, we have found that the cinnamate side groups could be also reacted by thermal energy, and this reaction is presumed to attribute to the radical reaction of carbon double bond in the cinnamate groups. Contrary to the photocycloaddition reaction of the cinnamate side groups, the thermal reaction of cinnamate side group was closely related to the flexibility of polymer backbone. The difference of the mechanism between the photocycloaddition reaction and thermal crosslinking reaction was confirmed by $^1H-NMR$$ and $^{13}C-NMR$ analysis of the model compound.

• Journal of Biosystems Engineering
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• 제16권3호
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• pp.290-297
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• 1991

For the efficient utilization of the solar thermal energy to overcome the time gap between to supply and demand, an efficient heat storage technique, especially high density-latent-heat storage system, is necessary. In this study, the performance of a panel type latent heat storage equipment during heat discharging process was analyzed theoretically and experimentally. In order to find out the performance of the system, computer simulation programs were developed by finite difference method. The governing equations were constructed by two dimensional heat conduction model with moving boundary. The results of the experimental and the theoretical analysis were reasonably well agreed. The efficiencies of the double pipe type and the panel type latent heat storage equipment were compared.

• 한국농공학회논문집
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• 제48권5호
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• pp.51-60
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• 2006

In order to examine the heat transfer characteristic of a soil warming system and effects of soil warming on the greenhouse heating load, control experiments were performed in two greenhouses covered with double polyethylene film. One treated the soil warming with an electric heat wire and the other treated a control. Inside and outside air temperature, soil temperature and heat flux, and heating energy consumption were measured under the set point of heating temperature of $5,\;10,\;15,\;and\;20^{\circ}C$, respectively. Soil temperatures in a soil warming treatment were observed $4.1\;to\;4.9^{\circ}C$ higher than a control. Heating energy consumptions decreased by 14.6 to 30.8% in a soil warming treatment. As the set point of heating temperature became lower, the rate of decrease in the heating energy consumptions increased. The percentage of soil heat flux in total heating load was -49.4 to 24.4% and as the set point of heating temperature became higher, the percentage increased. When the set point of heating temperature was low in a soil warming treatment, the soil heat flux load was minus value and it had an effect on reducing the heating load. Soil heat flux loads showed in proportion to the air temperature difference between the inside and outside of greenhouse but they showed big difference according to the soil warming treatment. So new model for estimation of the soil heat flux load should be introduced. Convective heat transfer coefficients were in proportion to the 1/3 power of temperature difference between the soil surface and the inside air. They were $3.41\;to\;12.42\;W/m^{2}^{\circ}C$ in their temperature difference of $0\;to\;10^{\circ}C$. Radiative heat loss from soil surface in greenhouse was about 66 to 130% of total heating load. To cut the radiation loss by the use of thermal curtains must be able to contribute for the energy saving in greenhouse.

• 대한기계학회논문집
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• 제17권5호
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• pp.1150-1160
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• 1993

본 연구에서는 보압과정시 급속한 압력구배에 의한 관성항의 영향을 고려하기 위해 수정된 Hele-Shaw 모델과 압축열 발생항, 온도와 압력의 변화에 따른 수지의 밀 도 이완현상에 대한 모델의 도입 및 유한요소법을 이용한 수치해석적 방법을 제시하여 정확한 잔류압력을 구하고 성형조건 및 물성치에 따른 수지의 거동을 살펴보고자 한다.

• 대한조선학회논문집
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• 제31권3호
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• pp.87-99
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• 1994

Reynolds Averaged Navier-Stokes 방정식을 수치해석하여 Wigley 선형 주위의 난류유동을 계산하였다. 정규격자상에서 공간의 이산화는 2차 정도의 유한차분법을, 시간의 적분에는 4단계 Runge-kutta법을 이용하였다. 시간 증분을 크게 하기 위하여 Jameson의 잔류항 평균 기법을 사용하였다. 압력 Poisson 방정식으로부터 압력장을 구하였고 난류닫음 조건을 만족시키기 위하여 Baldwin-Lomax의 난류 모형을 사용하였다. 수치계산은 레이놀드수가 $4.5{\times}10^6$에서 수행하였고 계산된 속도와 압력분포는 실험 결과와 비교적 잘 일치하는 것을 확인하였다.