• 제목/요약/키워드: Chang's Method

검색결과 3,722건 처리시간 0.036초

DSM 모니터링을 위한 확산 모형의 계수 추정 (Parameter Estimation of the Diffusion Model for Demand Side Management Monitoring System)

  • 김진오;최청훈;김정훈;이창호;김창섭
    • 대한전기학회논문지:전력기술부문A
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    • 제48권10호
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    • pp.1183-1189
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    • 1999
  • This paper presents the method of parameter estimation of diffusion model for monitoring Demand-Side Management program. Bass diffusion model was applied in this paper, which has different values according to the following parameters; coefficients of innovation, imitation and potential adopters. Though it is very important to estimate three parameters precisely, there has been no empirical way in practice. Thus, this paper presents the method of parameter estimation in case of few data with constraints to reduce the possibility of bad estimation. The constraints can be empirical results or expert's decision. Case studies show the diffusion curves and forecasted values of the peak for the high-efficient lighting. The feedback and nonlinear least-square parameter estimation methods used in this paper enable us to evaluate the status and to predict the effect of DSM program.

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Q-BOM(Quality-BOM) 기반의 품질보증 효율화 방안 연구 (A Study on the Improvement of Efficiency for Quality Assurance Based on Quality-Bill of Material)

  • 이창희;양경우;박두일;김상부
    • 품질경영학회지
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    • 제41권3호
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    • pp.457-463
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    • 2013
  • Purpose: For effective quality assurance activities, BOM-based quality assurance method is presented. This study introduces various BOM conversions such as Q-BOM, T-BOM, and S-BOM based on M-BOM structure. Methods: Product quality control via Q-BOM manages inspection/audit information, overall supply-chain of product, part requirements, and inventory status. T-BOM manages part traceability, and S-BOM enables statistical control over key process and parts at various hierarchy levels. Results: Quality plan template was developed based on the study results of BOM system including Q-BOM, T-BOM, and S-BOM. Conclusion: Through BOM(Q-BOM, T-BOM, and S-BOM) study and development of quality plan template, more systematic and comprehensive quality management plan is achieved.

강판의 진동모드를 고려한 방사음 예측에 관한 연구 (Effect of the Vibration Modes on the Radiation Sound for Plate)

  • 김창남;변용수;김정만;김의간
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권1호
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    • pp.73-80
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    • 2006
  • In order to compute the radiated sound from a vibrating structure, the Rayleigh's integral equation has to be derived from the Helmholtz equation using Green's function. Generally, the surface velocity in the Rayleigh's integral equation uses the root mean square(rms) velocity. The calculation value is too large, because it's not considered cancelation. On the other hand. using the complex velocity, the sound pressure is calculated too small, because it considers that sound is perfectly canceled out. Therefore, this thesis proposes a correction factor(CF) which considers vibration modes and the method by which to calculate the radiating sound pressure. The theoretical results are compared with the experimental values, and the proposed method can be verified with confluence.

Model Identification of Hydraulic Pin-On-Disk type Tribotester with DDV

  • Kim, Seung-Hyun;Lee, Chang-Don;Lee, Jin-Kul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.170.1-170
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    • 2001
  • This paper developed the model for electro hydraulic force control system by identification method via ARMAX model. Implementation of Identification is performed on Pin-On-Disk type tribotester. The wear mechanism is an important mechanic property to select a material´s life and a optimum work condition. Pin-on-disk type tribotester is popular wear analysis experimental equipment and its mechanism is that adding a force on a rotating disk to simplify two surface contact´s wear experimental condition. Material´s rotating velocity and eccentricity rotation makes disturbance and it affects adding constant force. To get a high performance of force adding part, DDV(Direct Drive Valve) which has pressure control loop is used. To obtain a tribotester´ s ARMAX model, prediction error method(PEM) is used in case force adding part and rotating part is ...

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승용차용 연속가변 ER댐퍼의 성능연구 (Performance Investigation of a Continuously Variable ER Damper for Passenger Vehicles)

  • 김기선;장유진;최승복;정재천;서문석;여문수
    • 한국자동차공학회논문집
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    • 제3권6호
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    • pp.69-77
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    • 1995
  • This paper presents performance investigation of a continuously variable ER(Electro-Rheological) damper for passenger vehicles. A dynamic model of the damper is formulated by incorporating electric field-dependent Bingham properties of the ER fluid. The Bingham properties are experimentally obtained through Couette type electroviscous measurement with respect to two different particle concentrations. The governing equation of the hydraulic model treating three components of fluid resistances;electrode duct flow, check valve flow and piston gap flow, is achieved via the bond graph method. A prototype ER damper is then designed and manufactured on the basis of parameter analysis. The damping forces of the system are experimentally evaluated by changing the intensity of the electric field, the particle concentration and the electrode gap.

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한국과 미국의 1학년 초등수학 교사용 지도서에 관한 고찰 (A Note on Teacher's Guide Book of First Grade between Korea and United States of America)

  • 최창우
    • East Asian mathematical journal
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    • 제30권4호
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    • pp.385-404
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    • 2014
  • There are some researches for international comparing of textbook and curriculum, so far. But These researches focused on comparing special region of textbook or curriculum. On the contrary, there are hardly papers how teacher's guide is consists and different with other country. In this paper, we have analyzed teacher's guide of Korea and Everyday Mathematics which is one of the teacher's guide in the many counties in the united states of America. Especially, teaching method, differentiated contents of curriculum, characteristics of consists of curriculum and so on. On the basis of this analysis, we search the improvement points of teaching of primary mathematics and also we make all the primary school teachers realize the diversity of teaching method through foreign cases and consequently they will make use of these results as a reference material such as reconstruction of textbook.

A Modified Alkaline Hydrolysis of Total Ginsenosides Yielding Genuine Aglycones nad Prosapogenols

  • Im, kwang-Sik;Chang, Eun-Ha;Je, Nam-Gyung
    • Archives of Pharmacal Research
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    • 제18권6호
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    • pp.454-457
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    • 1995
  • To improve the yield of genuine aglycones from glycosides, the conditions of alkaline hydrolysis were investigated, and a modified method was established. The modified method empolyed pyridine as an aprotic solvent. To complete the hydrolysis and obtain 20(S)-protopanaxadiol (1) and 20(S)-protopanaxatriol(2), which are the genuine aglycones of ginsenosides, total ginsenosides were refluxed with sodium methoxide in pyridine. Addition of methanol, a protic polar solvent to the reaction miuxture, led partial hydrolysis yielding a mixture of the genuine prosapogenols. Of the prosapogenols compound 3 and 6 characteristically possessed D-glucopyranosyl moiety attached at the sterically hindered C-20 hydroxyl group. 3 and 6 were not obtaijned by other hydrolysisw methods except by the soil bacterial hydrolysis.

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Linear Stepping Motor의 추력 특성 개선에 관한 연구 (A Study on The Characteristics Improvement of Linear Stepping Motor)

  • 이상호;정도영;신미영;전선근;정종호;정원석;오흥석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 A
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    • pp.157-159
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    • 1999
  • We are analyzed the characteristics of maximum thrust and normal force for new model of HB typed LSM by using Finite Element Method and Virtual Work Method. As a result of this paper, it is confirmed that maximum thrust of the enhanced LSM increased 30% without increasing the input energy and the normal force.

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로봇 손 구동용 초음파 모터의 설계 (Design of the Ultrasonic Motor for Driving Robot Hand)

  • 박기준;백수현;김승호;정현규;정일록;장흥순
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 A
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    • pp.121-123
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    • 1999
  • The purpose of this paper is to establish a method of design of the Ultrasonic Motor for Driving Robot Hand. This method is based on two models for the ultrasonic motor(a two dimensional elastic contact model. electric equivalent circuit). And analyzed the basic model which installed in the module to match the suitable standard. As varied external diameter, internal diameter and thickness, the proper ultrasonic motor is implemented to find a targeted resonant-frequency and torque near to designed values.

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특이점분포방식(特異點分布方式)에 의한 비정상수중익문제(非正常水中翼問題)에 대(對)한 해석(解析) (Solution of Unsteady Hydrofoil Problems by Discrete Vortex Method with Application to Fish Propulsion)

  • 김형태;이창섭
    • 대한조선학회지
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    • 제18권3호
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    • pp.11-27
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    • 1981
  • This paper is prepared to solve the problem of two-dimensional sinusoidal motion of hydrofoil, which can be related not only to the prediction of unsteady forces acting on the marine propeller blade but to the study of aquatic animal's undulatory mode of propulsion. For convenience's shake, this manuscript can be devided into two parts. In the first part, the lift and moment coefficients have been calculated by the method of conformal transformation. In the other part, the thrust and the hydromechanical efficiency have been evaluated, using Lagally's technique having extended to the unsteady case, they also have been compared with the results, which had been obtained by Lighthill[6] and Wu[7] using Prandtl's acceleration potential.

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