• Title/Summary/Keyword: Resistance value

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The Determinants of User Resistance to Adopting e-Books : Based on Innovation Characteristics and User Attitude (전자책 수용에 대한 사용자 저항 결정요인 : 혁신특성과 사용자태도를 중심으로)

  • Lee, Aeri;Choi, Jaewon;Kim, Kyung Kyu
    • The Journal of Society for e-Business Studies
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    • v.17 no.4
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    • pp.95-115
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    • 2012
  • The e-Book market has rapidly grown as an innovative product which is mixed its traditional and technological characteristics. However, decreasing user resistance to the e-Book is very important to continually keeping up its market growth. Previous studies for user resistance have been studied as a negative barrier for various innovative products with importance of user resistance. Nevertheless, the factors for user' resistance to the e-Book field have not been found out considering both perceived value and switching cost. Especially, both innovative technology and user specifics should be considered when explaining user resistance to adopting e-Books. Thus, the purpose of this study is to understand the process for user resistance to the e-book and find out its antecedents with perceived value and switching cost at the same time. As a result, it appeared that triability, uncertainty and complexity affected perceived value and switching cost. The user-based antecedents like social norm and perceived value increased the effect of self-efficacy. Also, self-efficacy and perceived value decreased user resistance whereas switching cost increase user resistance to the e-Book perspective.

Bearing Capacity and Control Method of Driven Piles (기성말뚝의 지지력 거동해석과 시공관리방안)

  • 박영호;김경석
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.03a
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    • pp.249-258
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    • 1999
  • Dynamic load and static load tests are performed on steel pipe piles and concrete piles at five construction sites in highway to compare the difference of load bearing mechanisms. At each site, one steel pile is instrumented with electric strain gages and dynamic tests are performed on the pile during installation. Damages of strain gages due to the installation are checked and static test is performed upon the same pile after two or seven days as well. It shows that load transfer from side friction to base resistance behaves somewhat differently according to the results of load-settlement analysis obtained from PDA and static load test. Initial elastic stage of load settlement curves of two load tests is almost similar. But after the yielding point, dynamic resistance of pile behaves more stiffer than static resistance, thus, dynamic load test result might overestimate the real pile capacity compared with static result. Analysis of gage readings shows that unit skin friction increases exponentially with depth. The skin friction is mobilized at the 1∼2m above the pile tip and contributes to the considerable side resistance. Comparison of side and base resistances between the measured value and the calculated value by Meyerhof's bearing capacity equation using SPT N value shows that the calculated base resistance is higher than the measured. Therefore, contribution of side resistance to total capacity shouldn't be ignored or underestimated. Finally, based upon the overall test results, a construction control procedure is suggested.

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A Study on Gain of Feedforward Compensator about Source Voltage Variation of Three-phase Series Active Power Filter (3상 직렬형 능동필터의 입력전압변동에 대한 전향보상이득에 관한 연구)

  • Kwon H.N.;Nam N.J.;Kang B.H.;Choe G.H.;Han S.W.
    • Proceedings of the KIPE Conference
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    • 2001.12a
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    • pp.97-101
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    • 2001
  • Recently, as the development of industry, the nonlinear load becomes increased. Because of nonlinear load, the variation of source voltage is generated by the impedace of source side flowed harmonic currents. For blocking harmonic currents by nonlinear load, a series active power filter operates blocking resistance of harmonic currents. The value of blocking resistance shows ideal compensating characteristic out of theoretically infinite value. But the blocking resistance is limited by the problem of the system stability and the capacity of inverter. In this paper, the value of optimum blocking resistance is found by a simulation in the applied system. In the case of unbalanced source voltages, each relation of the blocking resistance is shown. It is proved that blocking resistance of series active power filter relates to a passive filter.

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A Study on Wearable Healthcare Device Adoption : An Integrated Approach of UTAUT2 and MIR (웨어러블 헬스케어 기기의 수용에 관한 연구: 확장된 통합기술수용모형과 혁신저항모형의 통합적 접근)

  • Jin, Seok;Ahn, Hyunchul
    • The Journal of Information Systems
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    • v.28 no.3
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    • pp.159-202
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    • 2019
  • Purpose The purpose of this study is to explain users' wearable healthcare device adoption using performance expectancy, effort expectancy, the hedonic motivation and price value of UTAUT2, and to identify the causal relationship between intention to use wearable healthcare device and innovation resistance formed by perceived risks. Design/methodology/approach The research model proposed in this study is based on UTAUT2(Extended Unified Theory of Acceptance and Use of Technology) and MIR(Model of Innovation Resistance). In specific, performance expectancy, effort expectancy, hedonic motivation and price value of UTAUT2 and innovation resistance formed by perceived risks of MIR are adopted in our research model. To validate the research model, we carry out the analysis of the survey data using Smart PLS 3.0 to test the hypotheses. Findings According to the empirical analysis results, this study confirms that the performance expectancy, effort expectancy, hedonic motivation, and price value have significant effects on the intention to use wearable healthcare devices. It also finds that perceived risk affects innovation resistance and in turn, innovation resistance affects the intention to use wearable healthcare devices.

A Study on Composites of Ethylene-Vinyl Acetate Copolymer and Ethylene-Propylene-Diene Rubber with Aluminum Hydroxide as a Fire Retardant

  • Lee, Yu Jun;Lee, Su Bin;Jung, Jae Young;Lee, Dam Hee;Cho, Ur Ryong
    • Elastomers and Composites
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    • v.51 no.2
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    • pp.93-98
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    • 2016
  • The composites of EVA/EPDM including aluminum trioxide (ATH) as a fire retardant were manufactured for the purpose of improving low temperature property and flame resistance in the rubbery materials. The ratio of EVA to EPDM didn't affect the flame resistance of the rubber composites. The addition of ATH resulted in increase of the flame resistance. In the evaluation of the cold resistance, the increasing EPDM content showed enhancement of cold resistance in the composites due to increasing low Tg EPDM. It was found out that tensile strengths of the composites showed a maximum value at 100 phr of ATH by reinforcing effect, but a minimum value at 200 phr of ATH owing to slippage between the flame retardant by the external stress. In the measurement of solvent resistance in tetrahydrofuran, the increasing ATH content yielded enhancement of solvent resistance by reducing swelling of the composite, and increasing EPDM content also resulted from increase of the solvent resistance by reduction of polarizability as well as increase of crosslink in the composites.

A study on the parameter identification of induction motors (유도전동기의 매개변수 추정에 관한 연구)

  • 김규식
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.6
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    • pp.1-11
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    • 1996
  • The rotor flux level need be changed frequently for field weakening or power efficiency control. Motor inductances depend on rotor flux but not on machine temperature. On the other hand, rotor resistance varies greatly with the machine temperature. Motor parameters such a sinductances and rotor resistance should be known precisely in order to attain high dynamic performance of inductin motor. In this paper, efficient an dnovel identification algorithms for motor inductances and rotor resistance are presented. The rotor flux is changed. As the result, the slip frequency is varied. The identificatin algorithm for rotor resistance measures the varied slip frequency and alters the estimated rotor resistance. Then, the estimated value of rotor resistance will approach its real value. The proposed identification algorithms are computationally simple and have very small identification errors.

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Changes of Average Specific Resistance on Suspension Concentration (현탁액의 농도에 다른 여과 현균비저항값의 변화)

  • 장재선
    • Journal of Environmental Health Sciences
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    • v.22 no.1
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    • pp.12-20
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    • 1996
  • This study was carried out to investigate the change of average .specific resistance according to suspension concentration for study phenomena occurring during filtration period. As the results of this study, the following conclusions were obtained. The average specific resistance in 1% $CaCO_3$ suspension was showed power function(R=0.99), whereas in TOYO 5C and TOYO 5A paper were made little difference under high pressure. It represented from results that filtration theory in concord with cake filtration was no affected the average specific resistance of filter medium in cake filtration. In case of 0.1% $CaCO_3$ suspension filtration, the TOYO 5C was showed power function, whereas in TOYO 5A paper differently. In the present study, the $P_1$ value was calculated from the average specific resistance by filtration method. Therefore, $P_1$ value were $1.68\times 10^4Pa$, $4.05\times 10^3Pa$, and $3.15\times 10^3Pa$ in $5.3\times 10^4Pa$, $1.3\times 10^4Pa$, and $8.2\times 10^3Pa$, respectively. We concluded that propriety of new filtration theory was also proved.

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A measuring Method of Ground Resistance for Energized Power Systems (운전중인 전력설비의 접지저항 측정방법)

  • 이복희;김성원;엄주홍;이승칠
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2000.11a
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    • pp.77-81
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    • 2000
  • The purpose of this paper is to describe a new measuring method of ground resistance for the grounding system in energized power equipment and substations. It is very difficult to measure the accurate ground resistance in energized power equipment and substations because of the noise conducted from all external connections to the grounding system and harmonics components caused by unbalanced loads and overloads. The ground resistance that is measured with existing methods includes not only the effect of desired signals but also noise components for the measurement period in grounding system. The measured value of ground resistance can entirely be different from actual value. In this paper, to eliminate 60[Hz] power system interference and harmonic components the low-pass filter method was used in the measurement of ground resistance.

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DECOUPLING CONTROL OF AN INDUCTION MOTOR WITH RECURSIVE ADAPTATION OF ROTOR RESISTANCE

  • Kim, Gyu-Sik;Kim, Jae-Yoon;Yim, Chung-Hyuk;Kim, Joohn-Sheok
    • Proceedings of the KIPE Conference
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    • 1998.10a
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    • pp.23-28
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    • 1998
  • We propose a nonlinear feedback controller that can control the induction motors with high dynamic performance by means of decoupling of motor speed and rotor flux. The nonlinear feedback controller needs the information on some motor parameters. Among them, rotor resistance varies greatly with machine temperature. A new recursive adaptation algorithm for rotor resistance which can be applied to our nonlinear feedback controller is also presented in this paper. The recursive adaptation algorithm makes the estimated value of rotor resistance track its real value. Some simulation results show that the adaptation algorithm for rotor resistance is robust against the variation of stator resistance and mutual inductance. In addition, it is computationally simple and has small estimation errors. To demonstrate the practical significance of our results, we present some experimental results.

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Direct Torque Control Strategy (DTC) Based on Fuzzy Logic Controller for a Permanent Magnet Synchronous Machine Drive

  • Tlemcani, A.;Bouchhida, O.;Benmansour, K.;Boudana, D.;Boucherit, M.S.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.1
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    • pp.66-78
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    • 2009
  • This paper introduces the design of a fuzzy logic controller in conjunction with direct torque control strategy for a Permanent Magnet synchronous machine. A stator flux angle mapping technique is proposed to reduce significantly the size of the rule base to a great extent so that the fuzzy reasoning speed increases. Also, a fuzzy resistance estimator is developed to estimate the change in the stator resistance. The change in the steady state value of stator current for a constant torque and flux reference is used to change the value of stator resistance used by the controller to match the machine resistance.