• 설비공학논문집
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• 제19권10호
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• pp.735-741
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• 2007

An axial F.R.P. fan model for cooling tower is developed. The fan is designed using the equations for one dimensional inviscid flow through the fan blade. Fan shape is swept forward with a parabolic function. Calculations of the three dimensional turbulent flow around the fan are carried out to investigate performance of the fan. Data of the total pressure rise and hydraulic efficiency can be obtained for the various setting angles. Calculated values of the total pressure rise and hydraulic efficiency at the design point are less than those of the design specification. The prototype of the F.R.P. fan is made by laminating of the fiberglass and epoxy resins on the mold of fan shape.

• 한국컴퓨터정보학회논문지
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• 제11권6호
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• pp.27-33
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• 2006

본 논문에서는 컴포넌트 설계와 이를 기반으로 한 검색 프로토타입을 제시하였다. 재사용 단위로 단일 객체만을 대상으로 하게 되면 연관관계가 있는 객체간 상호작용을 이해하기 어렵고 관련성 유지가 어렵다. 따라서 본 논문에서는 재사용 단위로 클러스터링 컴포넌트 제안하였다. 이것은 객체간 관련성과 연관관계를 부여하여 사용자가 컴포넌트를 이해하고 검색할 수 있도록 하였다. 제안한 프로토타입 시스템은 애매한 검색 정의에 대하여 3가지 검색 환경을 제시하여 정확한 검색을 가능하게 하였다.

• 소음진동
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• 제8권4호
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• pp.670-682
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• 1998

Ball type automatic balancer is used to reduce the vibration caused by unbalance of rotor. In this study, A analytic modeling of a front loaded washing machine with ball type automatic balancer has been suggested theoretically and ADAMS has been used to analyze the dynamic characteristics of automatic balancer. It is found from simulation and experimental results that the automatic balancer suppress the steady state vibration of washing machine effectively. The test results match with the simulation results of ADAMS, thereby the dynamic model of ADAMS can be used as virtual prototype to predict the vibration characteristics which could be changed by the modification of design variableand can reduce the design cycle sharphy. To maximize the balancing effect of automatic balancer, the friction between balls and race and the deviation between geometric center and rotation center of drum need to be minimized and the optimum design for the stiffness of flange shaft and the angular acceleration of drum should be achieved.

• 전자공학회논문지SC
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• 제44권1호
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• pp.67-73
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• 2007

본 연구에서는 특정 자동차에 대한 Charging 시스템의 적합성 여부를 판별할 수 있는 충방전 Balance 시뮬레이터의 Prototype을 개발 하였다. 차량운전 환경요건에 따른 운전 패턴 등, 시뮬레이터의 구성을 위해 각종 전기부하와 이와 관련된 배터리 모델링을 하였고 실차실험을 행하여 그 데이터를 분석 정리하였다. 제안하는 모델과 분석된 데이터를 바탕으로 충방전 시뮬레이터를 개발하였고, 개발된 시뮬레이터는 정해진 차종으로 임의의 주행환경으로 운전할 때 차량의 전기에너지 공급 문제를 실차실험을 한 것과 같이 분석할 수 있다

• Journal of Power Electronics
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• 제13권4호
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• pp.507-515
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• 2013

This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved with a prototype interconnecting two battery banks. A second prototype has been constructed and tested for supercapacitor operation in constant power charge mode.

• 한국농공학회지
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• 제34권1호
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• pp.66-77
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• 1992

A prototype probabilistic approach to thickness design for asphalt pavement surface course was developed using first-order second moment probability model. The tensile strain (load effect) developing at the bottom of surface layer due to the wheel load and the critical strain (resistance) of asphalt concrete were used as random variables for pavement reliability analysis. Based on the parameters for load effect and resistance data collected from reference and field, simulated data were generated by Monte Carlo method for reliability evaluation of the pavement for a typical rural highway. Thickness of pavement surface course was defined in terms of target reliability of the pavement, growth factor of traffic, design life of pavement and resistance of the asphalt concrete to be placed on the pavement. According to these rationales, prototype thickness design chrats were sugested through example studies. From these, similar design charts can be developed for many pavements if appropriate data and target reliability are determined.

• 디자인학연구
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• 제20권2호
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• pp.53-64
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• 2007

Web development has multidisciplinary features involving diverse team members. Owing to the diverse backgrounds, however, there may be communication problems among web team members, especially between designers and programmers. Programmers often use a graphical modeling notation to communicate their designs. The graphical modeling concepts can also be helpful to designers, but most designers generally find graphical modeling notations hard to understand. We, therefore, propose an interactive computer-aided collaborative web design system including revised web graphical model notations to improve communication between web designers and programmers. We have designed and implemented a computational prototype to validate the approach and illustrate how the prototype works using concrete examples.

• 전기학회논문지
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• 제57권12호
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• pp.2208-2212
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• 2008

This paper deals with the cost reduction design of a single-phase line-start permanent magnet(LSPM) motor. Due to high cost of the permanent magnet(PM), cost reduction can be effectively achieved by reducing PM volume. Therefore, motor characteristics according to the PM volume are calculated by using d-q axis equivalent circuit analysis, and the characteristic map is made. In the characteristic map, maximum torque and efficiency are shown according to motor parameters such as back electromotive force(back emf) and inductances; back emf represents the PM volume. Minimum back emf and inductances satisfying output performance are determined in the characteristic map. Then, motor geometry based on the prototype motor is optimized to get the determined parameters using response surface methodology(RSM) and finite element method(FEM). Through the presented cost reduction design, total PM volume is reduced to 32% of prototype model.

• Journal of Power Electronics
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• 제6권1호
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• pp.1-7
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• 2006

This paper is a record of the study on a high efficiency and high power chopper based on the new soft switching method QRAS (Quasi~resonant Regenerating Active Snubber) designed for a Fuel Cell Electric Vehicle (FCEV). This power chopper is basically proposed for 25kHz soft switching. To confirm the practicality and effectiveness of the converter, the fabrication of a prototype-model using IGBTs was completed. Additionally, a 8kW rating test, a light load test, a current discontinuous mode test and a stable operation resonance test was completed. The circuit geometry, the basic operation, and the 8kW one-tenth-prototype test results are reported with a $97.5\%$ efficiency measurement.

• 한국공작기계학회논문집
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• 제10권5호
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• pp.104-109
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• 2001

Nowadays, Industrial competition power is depended on that rapidly produce the customized products. Therefor, it is necessary to reduce period of product development. Thus, concurrent engineering that work many process at a time was appeared and Rapid prototyping was appeared, it is method that rapidly produce the prototype. If the graphic model was made by CAD, the prototype can be made in short term. That provide what the part was directly tested by the worker. It provide a worker with believable data. We study on the influence of surface roughness on injection interval and part angle at FDM.