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Fault Location for Incomplete-Journey Double-Circuit Transmission Lines on Same Tower Based on Identification of Fault Branch

  • Wang, Shoupeng;Zhao, Dongmei;Shang, Liqun
    • Journal of Electrical Engineering and Technology
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    • v.12 no.5
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    • pp.1754-1763
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    • 2017
  • This paper analyses the characteristics of incomplete-journey double-circuit transmission lines on the same tower formed by single-circuit lines and double-circuit lines, and then presents a fault location algorithm based on identification of fault branch. With the relationship between the three-phase system and the double-circuit line system, a phase-mode transformation matrix for double-circuit lines can be derived. Based on the derived matrix, the double-circuit lines with faults can be decoupled, and then the fault location for an incomplete-journey double-circuit line is achieved by using modal components in the mode domain. The algorithm is divided into two steps. Firstly, the fault branch is identified by comparing the relationships of voltage amplitudes at the bonding point. Then the fault location, on the basis of the identification result, is calculated by using a two-terminal method, and only the fault distance of the actual fault branch can be obtained. There is no limit on synchronization of each terminal sampling data. The results of ATP-EMTP simulation show that the proposed algorithm can be applied within the entire line and can accurately locate faults in different fault types, fault resistances, and fault distances.

Update the finite element model of Canton Tower based on direct matrix updating with incomplete modal data

  • Lei, Y.;Wang, H.F.;Shen, W.A.
    • Smart Structures and Systems
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    • v.10 no.4_5
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    • pp.471-483
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    • 2012
  • In this paper, the structural health monitoring (SHM) benchmark problem of the Canton tower is studied. Based on the field monitoring data from the 20 accelerometers deployed on the tower, some modal frequencies and mode shapes at measured degrees of freedom of the tower are identified. Then, these identified incomplete modal data are used to update the reduced finite element (FE) model of the tower by a novel algorithm. The proposed algorithm avoids the problem of subjective selection of updated parameters and directly updates model stiffness matrix without model reduction or modal expansion approach. Only the eigenvalues and eigenvectors of the normal finite element models corresponding to the measured modes are needed in the computation procedures. The updated model not only possesses the measured modal frequencies and mode shapes but also preserves the modal frequencies and modes shapes in their normal values for the unobserved modes. Updating results including the natural frequencies and mode shapes are compared with the experimental ones to evaluate the proposed algorithm. Also, dynamic responses estimated from the updated FE model using remote senor locations are compared with the measurement ones to validate the convergence of the updated model.

Detecting Influential Observations in Multivariate Statistical Analysis of Incomplete Data by PCA (주성분분석에 의한 결손 자료의 영향값 검출에 대한 연구)

  • 김현정;문승호;신재경
    • The Korean Journal of Applied Statistics
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    • v.13 no.2
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    • pp.383-392
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    • 2000
  • Since late 1970, methods of influence or sensitivity analysis for detecting influential observations have been studied not only in regression and related methods but also in various multivariate methods. If results of multivariate analyses sometimes depend heavily on a small number of observations, we should be very careful to draw a conclusion. Similar phenomena may also occur in the case of incomplete data. In this research we try to study such influential observations in multivariate statistical analysis of incomplete data. Case of principal component analysis is studied with a numerical example.

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Damage identification of 2D and 3D trusses by using complete and incomplete noisy measurements

  • Rezaiee-Pajand, M.;Kazemiyan, M.S.
    • Structural Engineering and Mechanics
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    • v.52 no.1
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    • pp.149-172
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    • 2014
  • Four algorithms for damage detection of trusses are presented in this paper. These approaches can detect damage by using both complete and incomplete measurements. The suggested methods are based on the minimization of the difference between the measured and analytical static responses of structures. A non-linear constrained optimization problem is established to estimate the severity and location of damage. To reach the responses, the successive quadratic method is used. Based on the objective function, the stiffness matrix of the truss should be estimated and inverted in the optimization procedure. The differences of the proposed techniques are rooted in the strategy utilized for inverting the stiffness matrix of the damaged structure. Additionally, for separating the probable damaged members, a new formulation is proposed. This scheme is employed prior to the outset of the optimization process. Furthermore, a new tactic is presented to select the appropriate load pattern. To investigate the robustness and efficiency of the authors' method, several numerical tests are performed. Moreover, Monte Carlo simulation is carried out to assess the effect of noisy measurements on the estimated parameters.

Effect of Line-Width of Optical Sources on Performance of Spectral Amplitude Coding Optical CDMA Systems (광원 라인폭이 Spectral Amplitude Coding Optical CDMA시스템의 성능에 미치는 영향)

  • Jhee, Yoon Kyoo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.2
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    • pp.119-124
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    • 2015
  • In this paper, we analyze the effect of line-width of optical sources on the performance of spectral amplitude coding (SAC) optical code division multiple-access (OCDMA) systems. For a performance analysis we use a symmetric balanced incomplete block design (BIBD) code as the code sequence because we can construct a series of code families by choosing different values of q and m. The ideal BIBD code (m=2) requires narrower line-width than the nonideal BIBD codes when the effective power is large ($P_{sr}=-10dBm$). But the nonideal BIBD codes (m>2) need narrower line-width than the ideal BIBD code when $P_{sr}=-25dBm$.

A Study of Vibration Analysis Due to Structual Changes of Dynamic Structure (동적 구조물의 구조변화에 의한 진동해석 연구)

  • 현천성;이기형;정인성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.11
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    • pp.2033-2048
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    • 1992
  • This paper presents the theoretical development and qualitative evaluation of a new concept in the mathematical modeling of dynamic structures. We use both test data and analytical approximations to identify the parameters of an incomplete model. The model has the capability of predicting the response of the points of interest on the structure over the frequency range of interest and can be used to predict the changes in natural frequencies and normal modes due to structural changes. The theory was tested by running simulated tests on a relatively simple structure, identifying the parameters of the incomplete model, and using this model to predict the effects on frequency and mode shapes of several mass and stiffness changes. The conditions of the tests were varied by selecting different numbers of points of measurement, varying the frequency range, and by including assumed measurement error. It is recommended that the theoretical development be continued and that applications to more complex structures be carried out in order to develop a better understanding of the limitations and capabilities of the method. A successful, more definitive sevaluation could lead to immediate practical applications.

Dominance, Potential Optimality, and Strict Preference Information in Multiple Criteria Decision Making

  • Park, Kyung-Sam;Shin, Dong-Eun
    • Management Science and Financial Engineering
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    • v.17 no.2
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    • pp.63-84
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    • 2011
  • The ordinary multiple criteria decision making (MCDM) approach requires two types of input, alternative values and criterion weights, and employs two schemes of alternative prioritization, dominance and potential optimality. This paper allows for incomplete information on both types of input and gives rise to the dominance relationships and potential optimality of alternatives. Unlike the earlier studies, we emphasize that incomplete information frequently takes the form of strict inequalities, such as strict orders and strict bounds, rather than weak inequalities. Then the issues of rising importance include: (1) The standard mathematical programming approach to prioritize alternatives cannot be used directly, because the feasible region for the permissible decision parameters becomes an open set. (2) We show that the earlier methods replacing the strict inequalities with weak ones, by employing a small positive number or zeroes, which closes the feasible set, may cause a serious problem and yield unacceptable prioritization results. Therefore, we address these important issues and develop a useful and simple method, without selecting any small value for the strict preference information. Given strict information on both types of decision parameters, we first construct a nonlinear program, transform it into a linear programming equivalent, and finally solve it via a two-stage method. An application is also demonstrated herein.

Repair of Unilateral Incomplete Lesser Form Cleft Lip (편측성 불완전 소구순열의 치료)

  • Park, Hye Jeong;Jung, Hwi-Dong;Mulliken, John Butler;Jung, Young-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.3
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    • pp.178-183
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    • 2013
  • Cleft lip arises from congenital underdevelopment with various degrees and patterns. Mulliken named a unilateral incomplete cleft lip with no severe cleft as a lesser-form cleft lip and categorized it into three subgroups. Anatomically categorized subgroups are minor-form, microform, and mini-microform cleft by the extent of vermilion-cutaneous dysjuntion. The vermillion cutaneous notch is more than 3 mm from the regular Cupid's bow peak for minor-form, less than 3 mm for microform, and almost no gap with discontinuity on the vermillion cutaneous border for mini-microform. The treatments are rotational advancement flap for minor-form, double unillimb Z-plasty for microform, and vertical lenticular excision for mini-microform, respectively. This article aims to present the literature review about the incomplete lesser form cleft lip classified by Mulliken and to report our experiences.

White-light-emitting Organic Electroluminescent Device Based On Incomplete Energy Transfer

  • Song, Tae-Joon;Ko, Myung-Soo;Lee, Sung-Soo;Cho, Sung-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.701-705
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    • 2002
  • In order to realize full color display, two approaches were used. The first method is the patterning of red, green, and blue emitters using a selective deposition. Another approach is based on a white-emitting diode, from which the three primary colors could be obtained by micro-patterned color filters. White-light-emitting organic light emitting devices (OLEDs) are attracting much attention recently due to potential applications such as backlights in liquid crystal displays (LCDs) or other illumination purposes. In order for the white OLEDs to be used as backlights in LCDs, the light emission should be bright and have Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.33, 0.33). For obtaining white emission from OLEDs, different colors should be mixed with proper balances even though there are a few different methods for mixing colors. In this study, we will report a white organic electroluminescent device based on an incomplete energy transfer. In which the blue and green emission come from the same layer via incomplete energy transfer.

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Nonparametric Inference for the Recurrent Event Data with Incomplete Observation Gaps

  • Kim, Jin-Heum;Nam, Chung-Mo;Kim, Yang-Jin
    • The Korean Journal of Applied Statistics
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    • v.25 no.4
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    • pp.621-632
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    • 2012
  • Recurrent event data can be easily found in longitudinal studies such as clinical trials, reliability fields, and the social sciences; however, there are a few observations that disappear temporarily in sight during the follow-up and then suddenly reappear without notice like the Young Traffic Offenders Program(YTOP) data collected by Farmer et al. (2000). In this article we focused on inference for a cumulative mean function of the recurrent event data with these incomplete observation gaps. Defining a corresponding risk set would be easily accomplished if we know the exact intervals where the observation gaps occur. However, when they are incomplete (if their starting times are known but their terminating times are unknown) we need to estimate a distribution function for the terminating times of the observation gaps. To accomplish this, we treated them as interval-censored and then estimated their distribution using the EM algorithm proposed by Turnbull (1976). We proposed a nonparametric estimator for the cumulative mean function and also a nonparametric test to compare the cumulative mean functions of two groups. Through simulation we investigated the finite-sample performance of the proposed estimator and proposed test. Finally, we applied the proposed methods to YTOP data.