• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권5호
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• pp.591-595
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• 2010

본 논문에서는 자동화 컨테이너 터미널에서 컨테이너를 운반하는데 사용되는 무인 운반 차량(AGV)의 교통흐름을 동적으로 최적화하는 방안을 제안한다. 터미널 환경은 다수의 차량이 한정된 영역 내에서 주행하므로 높은 생산성을 위해서는 차량 사이의 간섭 및 병목현상을 최소화하도록 교통흐름을 제어해야 한다. 제안 알고리즘은 터미널 환경의 동적 변화에 대응하여 유전알고리즘을 이용하여 AGV의 교통흐름을 최적화한다. 알고리즘의 속도향상을 위해 이전에 수행한 최적화 결과를 활용하는 방안이 시도되었다. 시뮬레이션 실험을 통해 제안 알고리즘의 성능을 확인하였다.

• 한국생산제조학회지
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• 제9권3호
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• pp.83-89
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• 2000

In hydraulic control system turbine and gear motor type flowmeters are widely used to measure the flow rate under steady flow conditions. With the recent growth of interest in the measurement of instantaneous values of unsteady flow rate the test of the transient response of these flowmeters are in some significance. however an unsteady flow rate mea-surment and its calibration method with a fast response and a high accuracy have not beendeveloped. In this research particularly the dynamic characteristics of turbine and gear motor type flowmeters are investigated experimentally and simple mathematical models are proposed. The measured flow rate waveforms are compared with those by remote instan-taneous flow rate measurement method(RIFM) which has been developed by author and used for calibration As the result of frequency response test gain and phase between the measured flow rate waveforms by turbine type flowmeter and those estimated by RIFM are in good agreement up to 70Hz For the gear motor type flowmeter th simulated results by a math-ematical model proposed here agree well with the experiment nearly up to 100Hz. Also it if sound that the pressure drop across the flowmeter is increased in proportion to the frequency of the flow rate variation in a high frequency region of more than 100Hz. It can be explained that the dealy of gear motor type flowmeter in high frequency regionis mainly attributed to a first order delay consisting of the inertia of gears and internal leakage of the gear motor.

• 한국전산유체공학회지
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• 제7권3호
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• pp.53-59
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• 2002

A two-dimensional laminar flow through a channel with a pair of symmetric vertical fins is investigated. At far up- and down-stream from the fins, the plane Poiseuille flow exists in the channel. The Stokes flow for this channel is first investigated analytically and then the other laminar flows by numerical method. For analytic method, the method of eigen function expansion and collocation method are employed. In numerical solution for laminar flows, finite difference method(FDM) is used to obtain vorticity and stream function. From the results, the streamline patterns are shown and the additional pressure drop due to the attached fins and the force exerted on the fin are calculated. It is clear that the force depends on the length of fins and Reynolds number. When the Reynolds number exceeds a critical value, the flow becomes asymmetric. This critical Reynolds number Re/sub c/ depends on the length of the fins.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.101.3-101
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• 2002

Contents 1 Abstract- In the thermal power plant, there are six manipulated variables; main steam flow, feedwater flow, air flow, spray flow, fuel flow, and gas recirculation flow. Therefore, the thermal power plant control system is a multi-input and output system. In the control system, the main steam temperature typically is regulated by the fuel flow rate and the spray flow rate, and the reheater steam temperature is regulated by the gas recirculation flow rate. Up to the present time, the PID controller has been used to operate this system. This paper focuses on the characteristic comparison of the PID controller, the modified 2-DOF PID Controller on the DCS, in order to design an optimal...

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권6호
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• pp.1649-1667
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• 2012

In order to improve the accuracy and universality of the flow metric correlation analysis, this paper firstly analyzes the characteristics of Internet flow metrics as random variables, points out the disadvantages of Pearson Correlation Coefficient which is used to measure the correlation between two flow metrics by current researches. Then a method based on Symmetrical Uncertainty is proposed to measure the correlation between two flow metrics, and is extended to measure the correlation among multi-variables. Meanwhile, the simulation and polynomial fitting method are used to reveal the threshold value between different correlation degrees for SU method. The statistical analysis results on the common flow metrics using several traces show that Symmetrical Uncertainty can not only represent the correct aspects of Pearson Correlation Coefficient, but also make up for its shortcomings, thus achieve the purpose of measuring flow metric correlation quantitatively and accurately. On the other hand, reveal the actual relationship among fourteen common flow metrics.

• Journal of Advanced Marine Engineering and Technology
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• 제22권4호
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• pp.505-514
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• 1998

Flow pattern of air-water two phase flow depends on the conditions of pressure void fraction and channel geometry. We classify the flow pattern by measuring the output signal of the conductivity probe. under the classified flow pattern we mount a visualization equipment on the test section and take pictures. We vary the concentration of pure solvent and polymer to measure local void fraction. We know that the maximum point position of local void fraction distribution move from the center of the pipe to the wall of the pipe as JSL increase when JSA is constant in two phase flow. But we find that the maximum point position of local void friction move from the wal of the pipe to the center of the pipe when polymer concentration increase.

• Annals of Clinical Neurophysiology
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• 제1권1호
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• pp.64-69
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• 1999

Background : Syncope was defined as transient loss of consciousness and postural tone. The mechanisms of changes in cerebral hemodynamics during syncope have not been fully evaluated. Transcranial Doppler Ultrasonography can continuously monitor the changes in cerebral hemodynamics during head-up tilt (HUT). TCD could reveal the different patterns of changes in cerebral hemodynamics during syncope. Syncope without hypotension or bradycardia could be detected by TCD. We investigated the changes in cerebral blood flow velocity during HUT using TCD in 33 patients with a history of recurrent syncope or presyncope of unknown origin. Methods & Results : The positive responses were defined as presyncope or syncope with hypotension, bradycardia, or both. During HUT without isoproterenol infusion, there were a $86{\pm}23%$ drop in DV and a $41{\pm}34%$ drop in SV in 5 patients with positive reponses, and mean changes in those were less than 10% in patients with negative reponses (p=.00, p=.00). During HUT with isoproterenol infusion, TCD showed a $80{\pm}18%$ drop in diastolic velocity in 14 patients with positive reponses, and a $47{\pm}10%$ drop in that in patients with negative reponses (p=.00), however the change in systolic velocity did not differ. TCD showed three patterns during positive responses; loss of all flow, loss of end diastolic flow, and a decrease in diastolic velocity. Loss of consciousness occurred in the patients with loss of all flow or end-diastolic flow during positive reponses. Conclusions : TCD shows different patterns of changes in cerebral hemodynamics during HUT. TCD can be used to investigate the pathophysiology of neurocardiogenic syncope.

• 디지털콘텐츠학회 논문지
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• 제15권1호
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• pp.53-60
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• 2014

영화든 애니메이션이든 영상의 프레임에 담긴 쇼트들은 상당히 가변적이지만 클로즈업은 피사체에서 보여 지는 의미들을 부각시킨다. 영화에서의 클로즈업은 배우의 연기가 중요한 영향을 미치는 반면 애니메이션은 감독 및 애니메이터가 창조한 캐릭터의 연기를 대신하고 있어 클로즈업에 대한 이해가 우선되어야 한다. 이 연구는 애니메이션 내러티브에서 특별한 의미로 기능하는 클로즈업의 연출적 효과들을 극장용 애니메이션을 중심으로 고찰하였다. 클로즈업의 다양한 연출 효과들 중에서도 내러티브의 자연스러운 흐름과 관객의 감정이입으로 몰입을 유도하는 연출 효과를 중심으로 하였다. 내러티브의 자연스러운 흐름을 유도하는 연출 효과로 서술적 클로즈업을 분석하였으며, 캐릭터의 내면적 심리를 효과적으로 전달하여 관객의 감정이입을 유도하는 연출 효과로 심리적 클로즈업을 분석하였다. 마지막으로 극적인 효과를 창출하여 극의 몰입을 유도하는 상징적 클로즈업을 분석하여 애니메이션에서의 클로즈업 연출이 내러티브 전개의 완성도를 높이는데 기여할 수 있을 것으로 기대한다.

• 복식문화연구
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• 제20권3호
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• pp.347-362
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• 2012

Formatively and artistically aspect, a hybrid can be said to be a phenomenon in which two mutually different genres are combined. Make-up is thought to be very important to arrange the foundation available for predicting and pursuing a flow and direction of future hybrid make-up based on this, by analyzing a flow centering on hybrid trend, which was shown previously. In terms of objectives of this study, the first, aim is to suggest a model for researching make-up by grasping the developmental process and the characteristics of hybrid art through considering an art theory of hybridity, shown in make-up. The second, aim is to design make-up by analyzing trends in make-up style after deconstructing the hybrid genre. The modern make-up design through genre-deconstruction characteristics beyond diverse plurality and genre could be known to be highlighted as aesthetic characteristic by a slight attempt as communication of open space, which connects culture and genre, which had failed to be recognized and was neglected. Empirical research has, produced a work by systematically arranging make-up design. This study, identifies two kind of barrier demolition, such as the class deconstruction and the temporal, spatial disorder centering on genre deconstruction of hybrid. There are infinite possibilities in developing make-up design in line with modern sensation through aesthetic element and symbolic significance through genre deconstruction. It was the expression mode in future make-up, to providing basic data, and to strengthening competitive edge of culture and art.

• 동력기계공학회지
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• 제13권2호
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• pp.36-41
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• 2009

An experimental investigation was conducted to examine the fluid flow resistance in the rectangular channel with two inclined wire screen baffles. Two different types of wire screens; dutch weave and plain weave, were used as baffle devices in this experiment. Three kinds of baffles with different mesh specifications were made up of dutch type and four different kinds of baffles were made up of plain weave type. The stainless steel wire screen baffles were mounted on the bottom wall with varied angle inclination. Reynolds numbers were varied from 23,000 to 57,000. Results show that the mesh number of baffles plays an important role on friction factor behaviour. It is found that the baffle with the most number of meshes (type SA) has the highest fluid flow resistance.