• 제목/요약/키워드: loss factor

검색결과 2,791건 처리시간 0.027초

Evaluation of GIS-based Soil Loss Amount in Considering Basin Characteristics (유역특성을 고려한 GIS 기반 토양침식량 평가)

  • Guak Dong-Wook;Cho Gi-Sung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • 제24권1호
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    • pp.89-97
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    • 2006
  • Soil erosion has caused serious environmental problems which threaten the foundation of natural resources. In this paper, we chose RUSLE erosion model, which could be connected easily with GSIS and available generally in mid-scale watershed among soil erosion models, and extracted factors entered model by using GSIS spatial analysis method. First, this study used GIS database as soil map, DEM, land cover map and rainfall data of typhoon Memi (2003) to analyze soil loss amount of Dam basin. To analyze the changes of soil loss in considering basin characteristics as up-, mid- and downstream, this study calculated soil erodibility factor (K), topographic factors (LS), and cover management factor (C). As a result of analysis, K and LS factors of upstream showed much higher than those of downstream because of the high ratio of forest. But C factor of downstream showed much higher than that of upstream because of the high ratio of agricultural area. As a result of analysis of soil loss, unit soil loss of upstream is 4.3 times than soil loss of downstream. Therefore, the establishment of countermeasures for upstream is more efficient to reduce soil loss.

Design of Active Power Factor Corrector for Low Power Supply by Loss Free Resistor Concept (무손실 저항개념을 이용한 저전력 전원설비용 능동 역률보정기의 설계)

  • 임영철;정영국;최찬학;나석환;이건식;장영학
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • 제7권1호
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    • pp.30-36
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    • 1993
  • A simple discontinuous conduction mode(DCM) flyback type active power factor corrector for low power supply resents an effective resistive load to its power input. It is therefore well suited as an inexpensive high power factor rectifier for office equipment. An equivalent circuit model for the Active Power Factor Corrector based on the "Loss Free Resistor" concept is presented. This simple model correctly describes the basic power processing properties of the Active Power Factor Corrector, including input port resistor emulation, output port power some characteristics.teristics.

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Why to buy counterfeit luxury goods consumers have to spend? (소비자는 왜 위조명품을 구매하고 소비하는가?)

  • Yu, Seung-Yeob
    • Journal of Digital Convergence
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    • 제10권7호
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    • pp.115-121
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    • 2012
  • This study was to investigated why consumers buy counterfeit luxury goods, and to address questions about what was used. To this end, benefits consumers experience using counterfeit or what is profit? In addition, experience using counterfeit what is lost or dissatisfied? Based on the results of previous studies on the use counterfeit motivation, loss of use, benefits, and behavioral factors associated with motivation to learn using these counterfeit goods, benefits, and loss factor, each counterfeit product attitude and purchase intention was affects. First, the motivation for using counterfeit display, economics, satisfaction, usefulness, respectively. Counterfeiting in the attitude demonstrated motivation and quality had a significant impact. The economics of buying a counterfeit, satisfaction and quality significantly affected the motivation. Second, counterfeit benefits and economic benefits, personal benefits factor, respectively. Counterfeit goods on the attitude factor has significant effect personal benefit. Purchase of counterfeit goods, the economic and personal benefits also had a significant impact. Third, the loss factor counterfeit personal loss, quality loss, material loss, and social factors were lost. Attitude toward counterfeits were no significant factors that affect. The social cost of buying a factor had a significant impact. These findings on the behavior of consumers with counterfeit deep understanding helps. In addition, to reduce the future use of counterfeit campaign gives data that can be exploited.

HYBRID POWER FLOW ANALYSIS USING SEA PARAMETERS

  • Park, Y.H.;Hong, S.Y.
    • International Journal of Automotive Technology
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    • 제7권4호
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    • pp.423-439
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    • 2006
  • This paper proposes a hybrid analytic method for the prediction of vibrational and acoustic responses of reverberant system in the medium-to-high frequency ranges by using the PFA(Power Flow Analysis) algorithm and SEA(Statistical Energy Analysis) coupling concepts. The main part of this method is the application of the coupling loss factor(CLF) of SEA to the boundary condition of PFA in reverberant system. The hybrid method developed shows much more promising results than the conventional SEA and equivalent results to the classical PFA for various damping loss factors in a wide range of frequencies. Additionally, this paper presents applied results of hybrid power flow finite element method(hybrid PFFEM) by formulating the new joint element matrix with CLF to analyze the vibrational responses of built-up structures. Finally, the analytic results of coupled plate structures and an automobile-shaped structure using hybrid PFFEM were predicted successively.

Analysis of a Geometrically Asymmetric Trapezoidal Fin with Variable Fin Base Thickness and Height

  • Kang, Hyung-Suk
    • International Journal of Air-Conditioning and Refrigeration
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    • 제16권3호
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    • pp.83-88
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    • 2008
  • A geometrically asymmetric trapezoidal fin is analyzed using the one-dimensional analytic method. Heat loss and thermal resistance are represented as a function of the fin base thickness, base height, fm shape factor, inside fluid convection characteristic number, convection characteristic numbers ratio, fm length and ambient convection characteristic number. The relationship between the fin base height and the shape factor for equal amounts of heat loss is presented. One of the results shows that the variations of the fm base thickness and the inside fluid convection characteristic number give no effect on the thermal resistance.

Behavior of the Flexural Vibration of a Sandwich Beam with Partially Inserted Viscoelastic Layer (점탄성층이 부분적으로 삽입된 샌드위치보의 횡진동 특성)

  • 박진택;최낙삼
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 한국복합재료학회 2000년도 춘계학술발표대회 논문집
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    • pp.167-170
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    • 2000
  • The flexural vibration of a sandwich beam with partially inserted viscoelastic layer has been studied using the finite element analysis in combination with an experiment. Effects of length and thickness of partial viscoelastic layers on system loss factor(${\eta}_s$) and resonant frequency(${\omega}_r$) were considerably large. The thicker the viscoelastic layer in a sandwich beam, the larger the system loss factor in Mode 1 as compared with that in Mode 2. The loss factor increased almost linearly with increasing the length of partial viscoelastic layer. Effects of thickness of beams were also considered.

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Complex Antenna Factors of EMI Antenna with Coaxial Cable Balun for Measuring Electromagnetic Fields

  • Ju Chang-Hyun;Jun Dae-Hwa;Kim Ki-Chai
    • Journal of electromagnetic engineering and science
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    • 제5권2호
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    • pp.66-71
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    • 2005
  • The purpose of this paper is to present the complex antenna factor of an EMI dipole antenna with a balun consisting of two coaxial feeders(coaxial cable balun) for measuring electromagnetic fields. A new formula of complex antenna factors for an EMI antenna with coaxial cable balun is derived using by power loss concepts. The complex antenna factor shows that the present result in this study was identical with that of the result from S-parameters. The theoretical complex antenna factors derived by power loss concepts are in good agreement with the experiments.

Power Flow Analysis of Vibration of a Plate Covered with a Damping Sheet (제진 평판 진동에 대한 파워흐름해석)

  • Lee, Jin-Young;Kil, Hyun-Gwon;Song, Jee-Hun;Hong, Suk-Yoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • 제19권5호
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    • pp.530-536
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    • 2009
  • In this paper, the power flow analysis(PFA) has been used to analyze the vibration of a plate covered with a damping sheet. Experiments have been performed to measure the loss factor and frequency response functions of the plate covered with the damping sheet. The data for the loss factor has been used as the input data to predict the vibration of the coupled plates with PFA. The comparison between the experimental results and the predicted PFA results for the frequency response functions has been performed. It showed that PFA can be effectively used to predict structural vibration of a plate covered with a damping sheet in medium-to-high frequency range.

Freezing and Thawing Properties of Polypropylene Fiber Reinforced Eco-concrete (폴리프로필렌 섬유보강 에코콘크리트의 동결융해 특성)

  • Sung Chan-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • 제48권2호
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    • pp.59-66
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    • 2006
  • This study is performed to evaluate freezing and thawing properties of polypropylene fiber reinforced eco-concrete using soil, natural coarse aggregate, soil compound and polypropylene fiber. The mass loss ratio is decreased with increasing the content of natural coarse aggregate and soil compound, but it is increased with increasing the content of polypropylene fiber. The ultrasonic pulse velocity, dynamic modulus of elasticity and durability factor are increased with increasing the content of natural coarse aggregate and soil compound, but it is decreased with increasing the content of polypropylene fiber. The mass loss ratio, ultrasonic pulse velocity, dynamic modulus of elasticity and durability factor are $1.49{\sim}3.32%,\;1,870{\sim}2,465\;m/s,\;77X10^2{\sim}225X10^2\;MPa\;and\;84.6{\sim}92.8$ after freezing and thawing 300 cycles, respectively. These eco-concrete can be used for environment-friendly side walk and farm road.

Experimental Study On Power Flow Finite Element Method of Vibration of a Plate Partially Covered with a Damping Sheets (부분 제진 평판 진동 해석을 위한 파워흐름유한요소법의 실험적 연구)

  • Lee, Y.H.;Lee, J.Y.;Kil, H.G.;Hong, S.Y.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.496-497
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    • 2009
  • In this paper the power flow finite element method (PFFEM) has been used to analyze the vibration of a plate partially covered with a damping sheet. Experiments have been performed to measure the loss factor and frequency response functions of the plate partially covered with the damping sheet. The data for the loss factor has been used as the input data to predict the vibration of the coupled plates with PFFEM. The comparison between the experimental results and the predicted PFFEM results for the frequency response functions has been performed. It showed that PFFEM can be effectively used to predict structural vibration in medium-to-high frequency ranges.

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