• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1157-1159
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• 2003

The effect of the scan velocity modulation is studied. The effect of the velocity modulation on the picture image is judged from the intensity profile of the image. The intensity profile is obtained as time integral of moving Gaussian beam. To confirm the applicability of this integral formula, the measurement and simulation data is compared. And by calculating the intensity profile for different amounts of velocity modulation, the optimum modulation displacement that gives the best image quality is obtained. This optimum modulation displacement can be used in designing scan velocity modulation system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.454-457
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• 2005

Voloxidizer for hot cell demonstration that handle spend fuel of high radiation virulence in limited space should become a small size and not scatter in its exit. This study determine optimum velocity of $U_3O_8$ using Newton-Raphson Method. We have conducted fortran programing on the Newton-Raphson Method, obtained a theory results and, predicted optimum velocity on the particle size distribution of $U_3O_8$. We have conducted experimentation using acrylic experimental device for verification of theory method, sampled and analyzed using the particle size analyzer In the results, we have found maximum $5\~7\%$ error rate in the comparative value of theory and experimentation. Optimum velocity and experimental results of $U_3O_8$ for scatter prevention have applied for design of demonstration voloxidizer, and produced operation condition of voloxidizer.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.248-251
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• 2004

Stability of truck and trailer are the most significance in Thai automotive industry. This paper presents the mathematical model of a six-degree-of-freedom semi-trailer vehicle. Search method was implemented to obtain the optimum design variables of the trailer which are the distance from the fifth wheel to the centroid of the trailer and the distance from the centroid of the trailer to the trailer axel. The objective function is to minimize the steady side slip velocity, steady-state yawing velocity and steady-state angle between the tractor and the trailer. From the calculation , the optimum distance from the fifth wheel to the centroid of the trailer and the optimum distance from the centroid of the trailer to the trailer axle are 5.50 and 3.25 meters respectively. The stability of the optimal semi-trailer vehicle was also examined in steady state. The steady side slip velocity, yawing velocity and the angle between tractor and trailer are also obtained using linearization technique under unit step disturbance of the tractor front wheel steering angle.

• 한국기계가공학회지
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• 제7권4호
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• pp.142-148
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• 2008

This study aims to find the optimal cutting conditions, which are obtained by grinding condition, and the grinding characteristics and condition of constant velocity joint were investigated with respect to wheel velocity, depth of cut, feed speed. Grinding machine has been widely used in manufacturing optical reflects of metal. Such as steel are easy to be machined because of their proper material. As a result I obtained the data of grinding conditions makes good surface roughness and the optimal condition of grinding and get the mesh condition. The purpose of this study is to find the optimum grinding wheel characteristics for cutting constant velocity joint.

• Ocean Systems Engineering
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• 제2권2호
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• pp.83-97
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• 2012

In the present work, design procedure and computer simulation of an AUV are documented briefly. The design procedure containing the design of propulsion system and CFD simulation of hydrodynamics behavior of the hull leads to achieve an optimum mechanical performance of AUV system. After designing, a comprehensive one dimensional model including motor, propeller, and AUV hull behavior simulates the whole dynamics of AUV system. In this design, to select the optimum AUV hull, several noses and tails are examined by CFD tools and the brushless motor is selected based on the first order model of DC electrical motor. By calculating thrust and velocity in functional point, OpenProp as a tool to select the optimum propeller is applied and the characteristics of appropriate propeller are determined. Finally, a computer program is developed to simulate the interaction between different components of AUV. The simulation leads to determine the initial acceleration, final velocity, and angular velocity of electrical motor and propeller. Results show the final AUV performance point is in the maximum efficiency regions of DC electrical motor and propeller.

• 설비공학논문집
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• 제3권1호
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• pp.1-10
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• 1991

The purpose of this study is to lay groundwork for a complete analysis of two component flow by analyzing a single component flow made of continuous fluid without dispersed phase. In order to achieve uniform velocity distributions which are desirable in designing an optimum spray column direct contact heat exchanger, the influence of injection nozzle orientation has been investigated for axial and radial injections. The results that radial injection ensures more uniform velocity distributions compared to the axial case. The flow characteristics in a spray column have been investigated with various L/D values and inlet velocities, the most uniform internal velocity distributions have been obtained for the case of L/D=10 and 0.1m/sec. In the present investigation, it is shown that radial injection method for the continuous flow is advantageous in obtaining desirable uniform velocity distributions in a spray column. It is also found that as the value of L/D increases and the inlet velocity decreases, the flow improves to be better uniform velocity distributions.

• 한국유체기계학회 논문집
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• 제19권1호
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• pp.45-51
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• 2016

This study conducted CFD analysis on the mean velocity vector of distribution of the ejector driven pipe while changing the inlet velocity to 1 m/s at the diameter ratio of diffuser of 1:3, 1:2.25, 1:1.8 with the end position of driven pipe at 1, 1.253, 1.333, 1.467 respectively, which used $k-{\varepsilon}$/High Reynolds Number for the turbulence model, SIMPLE method for the analysis algorithm, and PIV experiment to verify the CFD analysis. As a result of the CFD analysis the optimum diameter ratio of ejector driven pipe was 1:3, the optimum end position of driven pipe was 1.333 for the diameter ratio of 1:3, 1:2.25, 1:1.8 and the PIV experiment obtained the same result as the CFD analysis. Therefore, the numerical analysis of the flow characteristics of ejector can be used for the optimum design implementation on ejector system.

• 대한기계학회논문집
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• 제12권5호
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• pp.1043-1054
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• 1988

본 연구에서는 공구(bite)의 형상에서 상면경사각을 변화시켜 이에 따른 절삭 저항의 3분력을 측정하여 그 값에 대한 합력과 비절삭저항 그리고 거칠기 등 3값을 normalization 과정으로 energy method에 의하여 이들 SM20C 및 SM45C 재료를 구분하 여 각각의 절삭저항과 그 특성을 규명하고져 하였으며 아울러 재료별 최적조건을 찾고 자 한다.

• 설비공학논문집
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• 제24권7호
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• pp.578-584
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• 2012

In this study, the analysis on the distribution of indoor airflow velocity and temperature by using numerical simulation has carried out to make fundamental data for establishing the optimum design of laboratory animal facilities. From the results, it was found that replacement of cage lacks, air supply and exhaust system, supply air temperature, supply air velocity affect to the optimum design of laboratory animal facilities as a important element.

• 설비공학논문집
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• 제15권5호
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• pp.439-445
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• 2003

The purpose of this study is to suggest the improvement strategies for exhaust performance in composite kitchen hoods. The Exhaust only hood, the 2-way compensating hood and the 3-way compensating hood were selected, and the laboratory experiments were performed to compare the local exhaust efficiency and the indoor temperature distributions according to the variations of the hood type and supply/exhaust air velocity. The results of this study can be summarized as follows. The compensating hood has better performance than exhaust only hood in the aspect of local exhaust efficiency and temperature distribution. The 3-way compensating hood shows the best performance when the supply air velocity is about 2.7 m/s, and the 2-way compensating hood at the supply air velocity of 3.5 w/s. In the same exhaust rate condition, if the exhaust area of the hood is increased and therefore the exhaust velocity is lowered, the supply air velocity is also lowered to get the optimum performance. The optimum exhaust velocity range of the commercial kitchen hood which derived from this study is 0.48 ∼ 0.55 m/s.