• Title, Summary, Keyword: sensitivity index

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Voltage Sensitivity Index Calculation using Dynamic Simulation (동적 시뮬레이션을 이용한 Voltage Sensitivity 지수 계산)

  • Jeong, Sung-Won;Park, In-Deok;Lee, Geun-Joon;Gim, Jae-Hyeon
    • Proceedings of the KIEE Conference
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    • pp.453-454
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    • 2007
  • This paper proposes the calculation method of voltage sensitivity index using CBEMA power acceptability curves and the voltage curves of the load bus to which momentary events occur. Voltage sensitivity index is represented by areas between two curves. Voltage sensitivity index is a parameter that depicts the ratio of a load disruption. The correlation between the installation cost of compensation devices and the voltage sag index on the bus can be used the validity of compensation.

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Geometric Sensitivity Index for the GNSS Using Inner Products of Line of Sight Vectors

  • Won, Dae Hee;Ahn, Jongsun;Sung, Sangkyung;Lee, Chulsoo;Bu, Sungchun;Jang, Jeagyu;Lee, Young Jae
    • International Journal of Aeronautical and Space Sciences
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    • v.16 no.3
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    • pp.437-444
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    • 2015
  • Satellite selection and exclusion techniques have been applied to the global navigation satellite system (GNSS) with the aim of achieving a balance between navigational performance and computational efficiency. Conventional approaches to satellite selection based on the best dilution of precision (DOP) are excessively computational and complicated. This paper proposes a new method that applies a geometric sensitivity index of individual GNSS satellites. The sensitivity index is derived using the inner product of the line of sight (LOS) vector of each satellite. First, the LOS vector is computed, which accounts for the geometry between the satellite and user positions. Second, the inner product of each pair of LOS vectors is calculated, which indicates the proximities of the satellites to one another. The proximity can be determined according to the sensitivity of each satellite. A post-processing test was conducted to verify the reliability of the proposed method. The proposed index and the results of a conventional approach that measures the dilution of precision (DOP) were compared. The test results demonstrate that the proposed index produces results that are within 96% of those of the conventional approach and reduces the computational burden. This index can be utilized to estimate the sensitivity of individual satellites, obtaining a navigation solution. Therefore, the proposed index applies to satellite selection and exclusion as well as to the sensitivity analyses of multiple GNSS applications.

Sensitivity Analysis Related to Redundancy of Regular and Irregular Framed Structures after Member Disappearance

  • Ito, Takumi;Takemura, Toshinobu
    • International Journal of High-Rise Buildings
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    • v.3 no.4
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    • pp.297-304
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    • 2014
  • Recently, there have been some reported examples of structural collapse due to gravity, subsequent to damage from accident or an excitation that was not prepared for in the design process. A close view of new concepts, such as a redundancy and key elements, has been taken with the aim of ensuring the robustness of a structure, even in the event of an unexpected disturbance. The author previously proposed a sensitivity index of the vertical load carrying capacity to member disappearance for framed structures. The index is defined as the ratio of the load carrying capacity after a member or a set of an adjacent member disappears, to the original load carrying capacity. The member with the highest index may be regarded as a key element. The concept of bio-mimicry is being applied to various fields of engineering, and tree-shaped structures are sometimes used for the design of building structures. In this study a sensitivity analysis is applied to the irregular-framed structures such as tree-shaped structures.

Refractive Index Characteristics of Optical Fiber (광섬유의 굴절을 특성)

  • Yuk, Jae-Ho
    • 전자공학회논문지 IE
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    • v.46 no.2
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    • pp.18-21
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    • 2009
  • The optical fiber refractive index sensors were fabricated using etching method and their refractive index characteristics have been investigated. Good sensitivity was shown at the region of 1.452-1.46 refractive index and operating point was shifted by wavelength. The sensitivity of sensor increased with decreasing cladding thickness and was stable with heat treatment. The hysteresis under cyclic refractive index changes was negligible.

Voltage collapse proximity index based on system apparent power loss sensitivity and its application to VAR investment (피상전력 손실감도에 의한 전압붕괴 근접도 지표와 무효전력 투자)

  • 이상중;김건중;김원겸;김용배;엄재선
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.44 no.10
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    • pp.1290-1294
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    • 1995
  • In this paper, a new voltage collapse proximity index (VCPI) based on system apparent power loss sensitivity is proposed. The newly proposed index .lambda.$^{Sloss}$ reaches -.inf. at system voltage collapse point and can be represented by .root..lambda.$^{Ploss}$$^{2}$+.lambda.$^{Qloss}$$^{2}$ where .lambda.$^{Ploss}$ and .lambda.$^{Qloss}$ are the VCPI based on the system active and reactive power loss sensitivity respectively. These indices can be used for the system VAR investment. .DELTA.Q [VAR] is invested, step by step, by the priority of the VCPI index given for each bus. The indices use information from normal power flow equations and their Jacobians. Computation time for deriving .lambda.$^{Sloss}$ is almost same as that for power flow calculation. Two case studies prove the effectiveness of the .lambda.$^{Sloss}$ index and the VAR investment algorithm proposed.

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Optimal Location of PSS and FACTS using Sensitivity Index (PSS와 FACTS의 감도기법을 이용한 위치 선정에 관한 연구)

  • Kim, Yang-Il;Ki, Kyung-Hyun;Jeung, Sung-Won;Gim, Jea-Hyeon
    • Proceedings of the KIEE Conference
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    • pp.221-223
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    • 2003
  • In this paper, a sensitivity index is proposed for identifying the location of FACTS in the power system with PSS. The index can be calculated by using the bus impedance matrix of the power system. This index that is related with sensitivity matrix is included in the network and not in operating condition for power system. This index is applied to IEEE 9 bus test system.

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Sweet Area Determination by Performance Sensitivity Analysis for an Automotive Vehicle Suspension (자동차용 현가장치의 성능감도해석에 의한 안정승차영역의 결정)

  • Park, Ho;Hahn, Chang-Su;Kim, Byeong-Woo;Kim, Dong-Gyu
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.12 no.1
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    • pp.92-100
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    • 2003
  • Using a quarter car model, an analytic method for performance estimation of a vehicle suspension system with respect to frequency response, RMS response and performance index is presented. From frequency response function, compromization of response performance to the whole frequency range is verified and from RMS response and performance index, sensitivity of ride md handling characteristics are examined. Using a full car model, sweet area(stable ride area) are determined and performance sensitivity is estimated according to the change of feedback gains. In order to esimate the output sensitivity, response we is displayed using a 3-dimensional contour plot. Design data n suggested for optimal design parameter esimation, which maximize the performance of the given suspension system.

A Study on the System Loss Minimizing Algorithm by Optimal Re-location of Static Condenser Using System Power Loss Sensitivity (계통손실 감소를 위한 전력용 콘덴서의 適正 再配置에 대한 연구)

  • 이상중;김건중;정태호;김원겸;김용배
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.44 no.1
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    • pp.21-24
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    • 1995
  • The larger and the more complicated the system size and configuration grow, the more serious the system loss problem becomes. Exessive system loss causes severs system voltage depression, which even may result in system voltage collapse. This paper proposes an effective tool for minimizing the system power loss by optimal re-location of the static condenser based on the system loss sensitivity index .lambda.$_{Q}$. It is possible to determine the optimal location and amount of VAR investment for minimizing the system loss by priority of .lambda.$_{Q}$ index given for each bus. Several computational techniques for avoiding divergency of the load flow solution are proposed. The loss sensitivity index .lambda.$_{Q}$ uses information of normal power flow equations and their Jacobians. Two case studies proved the effectiveness of the algorithm proposed.posed.

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Determining the Number of Risk Level Using Real-time Sensitivities in the Probabilistic Maritime Risk Evaluation (확률기반 해상위기평가에서 실시간 민감도를 이용한 위기수준의 단계 구분 수 결정에 관한 연구)

  • Gang, Sang-Guen
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.6
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    • pp.685-691
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    • 2014
  • The result of probabilistic maritime risk evaluation is represented by the probability(P=0.0~1.0) These results are shown by an index using Risk Acceptance Criteria(RAC) to base the evaluation generally to know the risk level easily. Current RAC is divided into 3 steps, 5 steps, 7 steps, etc. Despite need to evaluate whether the number of RAC for risk evaluation is reasonable, there is not a related research yet. In this study, It was proposed the evaluation method to determine the optimum index number of RAC using the Sensitivity distribution characteristics and the Sensitivity by the index number of RAC. As application result from the proposed method for probabilistic risk evaluation data obtained from the prior studies, It could be determined the optimum index number of RAC by Sensitivity below 10 times and confirmed that the proposed method is reasonable by this study.

Performance improvement of a vehicle suspension by sensitivity analysis (민간도해석에 의한 자동차 현가장치의 성능개선에 관한 연구)

  • Song, Chuck-Gee;Park, Ho;Oh, Jae-Eung;Yum, Sung-Ha
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1464-1473
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    • 1990
  • Optimal design parameters are estimated from the sensitivity function and performance index variation. Suspension design modification for performance improvement and basic materials for practical applications are presented. The linear quarter model of a vehicle suspension is analyzed in order to represent the utilities of sensitivity analysis, and sensitivity function is determined in the frequency domain. The change of frequency response function is predicted, which depends on the design parameter variation and the property is verified by computer simulation. As an investigation results of sensitivity function for the vibrational amplitude of sprung mass to road profile input, it is shown that the most sensitive parameters are the suspension damping and the suspension stiffness. In order to identify the effects of these two parameters to the performance of suspension system, the performance index variation according to the changes of parameters is considered and then optimal design parameters are determined. It is verified that the system response is improved noticeably in the both of frequency and time domain after the design modification with the optimal parameters.