• 천문학논총
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• 제8권1호
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• pp.33-45
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• 1993

The variation of instrumental profile for the different scan speed of PDS is estimated as FWHM of the assumed Gaussian Profile. The effects of scan speed and scan aperture of PDS on the objective prism spectrum analysis are investigated for 8 combinations of scan speed and scan aperture. Amomg them. D1 apture with 15 csu is found to be the most optimum choice for measuring KISO objective prism film. We suggest the preliminary test study of the scan speed and aperture for the optimum use of PDS for any massive scan of spectra. The optimum scan speed and aperture depends on the dispersion of spectrum as well as the type of phtographic emulsion.

• 한국지능시스템학회논문지
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• 제6권2호
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• pp.90-96
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• 1996

This paper presents a method that determines the stern profile dimensions for full, slwo-speed ship using fuzzy modeling, which is applied the genetic algorithm and the Hooke & Jeeves method. The infreed stern profile dimensions have compared with real ships.

• 제어로봇시스템학회논문지
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• 제12권3호
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• pp.208-220
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• 2006

Energy of wheeled mobile robot is usually supplied by batteries. In order to extend operation time of mobile robots, it is necessary to minimize the energy consumption. The energy is dissipated mostly in the motors, which strongly depends on the velocity profile. This paper investigates various 3-step (acceleration - cruise - deceleration) speed control methods to minimize a new energy object function which considers the practical energy consumption dissipated in motors related to motor control input, velocity profile, and motor dynamics. We performed an analysis on the energy consumption various velocity profile patterns generated by standard control input such as step input, ramp input, parabolic input, and exponential input. Based on these standard control inputs, we analyzed the six 3-step velocity profile patterns: E-C-E, P-C-P, R-C-R, S-C-S, R-C-S, and S-C-R (S means a step control input, R means a ramp control input, P means a parabolic control input, and E means an exponential control input, C means a constant cruise velocity), and suggested an efficient iterative search algorithm with binary search which can find the numerical solution quickly. We performed various computer simulations to show the performance of the energy-optimal 3-step speed control in comparison with a conventional 3-step speed control with a reasonable constant acceleration as a benchmark. Simulation results show that the E-C-E is the most energy efficient 3-step velocity profile pattern, which enables wheeled mobile robot to extend working time up to 50%.

• 한국생산제조학회지
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• 제8권2호
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• pp.137-143
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• 1999

The study of the high speed machining of inclined plane using ball end mill is performed. The use of ball end mill is rapidly growing in die and mold manufacturing. The cutting characteristics, such as cuttin g force, surface roughness and surface profile, are varied according to the variation of cutting directions. Free surface is cut using ball end mill, the surface profile is greatly varied depending upon the cutting direction. So this study will deal with the characteristics of cutting such as cutting efficiency according to the inclined plane of the workpiece, the cutting force according to tool path, surface profile and the roughness of surface. The optimal cutting direction to be applied the cutting for 3-D sculptured surfaces can be show through the results of this study.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.98-103
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• 2006

The hunting is the natural characteristics of the railway wheelset which is originated from the contact between the conical type wheel profile and rail. The critical speed of rolling-stock is called when the hunting is occurred, and it is closely connected with vehicle stability. The parameters which influence the hunting motion are like wheel profile, primary spring property and wheelset dimension, etc. The studies for these parameters are reported diversely. In this study, we aim to analyze the influence of parameters on hunting with the change of wheel profile produced by wheel wear and material property produce by aging of primary spring. For this, we made a dynamic model for wheelset and vehicle. Using these models, we analyzed the critical speed with the variations of the parameters like as wheel profile and primary spring property and we show the results.

• Current Optics and Photonics
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• 제2권6호
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• pp.568-575
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• 2018

Various techniques to measure the three-dimensional (3D) surface profile of a 3D micro- or nanostructure have been proposed. However, it is difficult to apply such techniques directly to industrial uses because most of them are relatively slow, unreliable, and expensive. The HiLo optical imaging technique, which was recently introduced in the field of fluorescence imaging, is a promising wide-field imaging technique capable of high-speed imaging with a simple optical configuration. It has not been used in measuring a 3D surface profile although confocal microscopy originally developed for fluorescence imaging has been adapted to the field of 3D optical measurement for a long time. In this paper, to the best of our knowledge, the HiLo optical imaging technique for measuring a 3D surface profile is proposed for the first time. Its optical configuration and algorithm for a precisely detecting surface position are designed, optimized, and implemented. Optical performance for several 3D microscale structures is evaluated, and it is confirmed that the capability of measuring a 3D surface profile with HiLo optical imaging technique is comparable to that with confocal microscopy.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.592-597
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• 2003

To solve a problem of micro drive due to small size and portability, it is necessary to understand and to investigate micro drive widely ,deeply. So, we performed modal analysis of suspension of micro drive, and load/unload experiment for Input current to VCM coil and disk speed. To determine the effect of ramp profile, curve fitting of lateral speed is performed with equation of speed. The results indicate that small load/unload speeds decrease the number of head/disk contacts, and during unloading process, low disk speed increase the number of head/disk contacts.

• 한국공작기계학회논문집
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• 제16권6호
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• pp.125-132
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• 2007

Inherent dynamic interaction between flexible disk and workpiece creates partially non-flat surface profile. A flat zone was defined using minimum depth of engagement. Several key parameters were defined to explain the characteristics of the zone. Process conditions including disk rotation speed, initial depth of cut and feed speed were varied to produce product profile database. Correlation between key factors was examined to find the characteristic dependencies. Trends of key parameters were displayed and explained. Higher flat zone ratio was observed for lower depth of cut and higher disk rotation speed. Ratio of minimum depth of cut against target depth of cut increased for higher feed speed and disk rotation speed but was insensitive to the depth of cut variation. The process transition was visualized by continuously displaying instantaneous orientation of the deflected disk and the location of key parameters were clearly marked for comparison.

• 전자공학회논문지
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• 제52권4호
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• pp.23-29
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• 2015

본 논문에서는 수중 위치 추적(Underwater Localization)을 위한 수평거리 추정 방식 중 음선의 각도 변화를 이용하는 방식을 개선하는 Look-up Table(LUT)를 사용하는 방식을 제안하고 기존 방식과의 연산속도 및 수평거리 오차를 비교한다. LUT를 사용하여 추정하는 방식은 수신기의 음파 도달 시간(Time of arrival : ToA)과 깊이에 따른 Sound Speed Profile(SSP)을 이용하여 만들어진 수평 거리-ToA table을 이용한다. 결과적으로, 음선의 각도 변화를 이용하는 방식에 비해 수평거리 추정오차는 다소 증가하게 되지만, 수신된 ToA에 대응되는 수평거리를 사용한다는 점에서 실시간으로 각도 변화를 추정하는 기존방식에 비하여 매우 빠른 처리가 가능하다.

• 대한조선학회논문집
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• 제33권1호
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• pp.153-160
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• 1996

본 연구에서는 유전자 알고리즘을 적용한 퍼지모델링 기법을 이용하여 저속비대선에서 선미형상의 주요치수를 결정하고, 이를 실적선과 비교하였다.