• Title/Summary/Keyword: Weighting method

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Document Summarization using Weighting based on Cloud (클라우드 기반의 가중치에 의한 문서요약)

  • Park, Sun;Kim, Chul Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.968-969
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    • 2013
  • In this paper, we proposes a document summarization method using the weighting based on cloud. The proposed method can minimize the user intervention to use the relevance feedback. It also can improve the quality of document summaries because the inherent semantic of the sentence set are well reflected by term weighting derived from semantic feature using nonnegative matrix factorizaitno based cloud.

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Analysis of Nested Case-Control Study Designs: Revisiting the Inverse Probability Weighting Method

  • Kim, Ryung S.
    • Communications for Statistical Applications and Methods
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    • v.20 no.6
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    • pp.455-466
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    • 2013
  • In nested case-control studies, the most common way to make inference under a proportional hazards model is the conditional logistic approach of Thomas (1977). Inclusion probability methods are more efficient than the conditional logistic approach of Thomas; however, the epidemiology research community has not accepted the methods as a replacement of the Thomas' method. This paper promotes the inverse probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be easily computed using existing software. Simulation studies demonstrate that this approach yields valid type 1 errors and greater powers than the conditional logistic approach in nested case-control designs across various sample sizes and magnitudes of the hazard ratios. A generalization of the method is also made to incorporate additional matching and the stratified Cox model. The proposed method is illustrated with data from a cohort of children with Wilm's tumor to study the association between histological signatures and relapses.

A Selection of Optimal Weighting matrix for Model Following Multivariable Control System to Boiler-Turbine Equipment Using GA (GA를 이용한 보일러-터빈 설비의 모델 추종형 다변수 제어 시스템 설계를 위한 취적 가중치 행렬의 선정)

  • ;黃現俊
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.13 no.2
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    • pp.234-234
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    • 1999
  • The aim of this paper is to suggest a design method of the optimal model following control system using genetic algorithm (GA). This control system is designed by applying GA with reference model to the optimal determination of weighting matrices Q, R that are given by LQ regulator problem. The method to do this is that all the diagonal elements of weighting matrices are optimized simultaneously by GA, in the search domain selected adequately. And we design the model following control system to boi1er-turbine equipment by the proposed method. The model following control system designed by this method has the better command tracking performance than that of the control system designed by the trial-and-error method. The effectiveness of this control system is verified by computer simulation.

Database Investigation Algorithm for High-Accuracy based Indoor Positioning (WLAN 기반 실내 위치 측위에서 측위 정확도 향상을 위한 데이터 구축 방법)

  • Song, Jin-Woo;Hur, Soo-Jung;Park, Yong-Wan;Yoo, Kook-Yeol
    • IEMEK Journal of Embedded Systems and Applications
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    • v.7 no.2
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    • pp.85-93
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    • 2012
  • In this paper, we proposed Wireless LAN (WLAN) localization method that enhances database construction based on weighting factor and analyse the characteristic of the WLAN received signals. The weighting factor plays a key role as it determines the importance of Received Signal Strength Indication (RSSI) value from number of received signals (frequency). The fingerprint method is the most widely used method in WLAN-based positioning methods because it has high location accuracy compare to other indoor positioning methods. The fingerprint method has different location accuracies which depend on training phase and positioning phase. In training phase, intensity of RSSI is measured under the various. Conventional systems adapt average of RSSI samples in a database construction, which is not quite accurate due to variety of RSSI samples. In this paper, we analyse WLAN RSSI characteristic from anechoic chamber test, and analyze the causes of various distributions of RSSI and its influence on location accuracy in indoor environments. In addition, we proposed enhanced weighting factor algorithm for accurate database construction and compare location accuracy of proposed algorithm with conventional algorithm by computer simulations and tests.

Enhancing Document Clustering Using Term Re-weighting Based on Semantic Features (의미특징 기반의 용어 가중치 재산정을 이용한 문서군집의 성능 향상)

  • Park, Sun;Kim, Kyungjun;Kim, Kyung Ho;Lee, Seong Ro
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.2
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    • pp.347-354
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    • 2013
  • In this paper, we propose a enhancing document clustering method using term re-weighting by the expanded term. The proposed method extracts the important terms of documents in cluster using semantic features, which it can well represent the topics of document to expand term using WordNet. Besides, the method can improve the performance of document clustering using re-weighting terms based on the expanded terms. The experimental results demonstrate appling the proposed method to document clustering methods achieves better performance than the normal document clustering methods.

A Comparison of an Improvement Performance of S/N ratio with the Method of Weighting in DMTI System using a Uniform Pulse Train (일정한 펄스 예을 사용한 DMTI 시스템에서 Weighting 방법에 따른 S/N 북 개선 특성에 관한 비교)

  • Go, Seong-Seon;Lee, Jae-Gyun;Yun, Hyeon-Bo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.1
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    • pp.41-45
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    • 1985
  • A degradation of the signal-to-noise ratio (SNR) in a digital moving target indicator system (DMTI System) can be Improved by weighting of the DMTI output pulses before the integration process. and it Is shown that the signal-to-noise ratio Is unproved as the nunlber of delay line cancellers. It is Known that signal-to-noise ratio obtained with optimum weighting is greater than that obtained with binomial weighting. An improvement performance of the signal-to-noise ratio for each case is presented through the results or a computter simulation.

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A Dynamic feature Weighting Method for Case-based Reasoning (사례기반 추론을 위한 동적 속성 가중치 부여 방법)

  • 이재식;전용준
    • Journal of Intelligence and Information Systems
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    • v.7 no.1
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    • pp.47-61
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    • 2001
  • Lazy loaming methods including CBR have relative advantages in comparison with eager loaming methods such as artificial neural networks and decision trees. However, they are very sensitive to irrelevant features. In other words, when there are irrelevant features, larry learning methods have difficulty in comparing cases. Therefore, their performance can be degraded significantly. To overcome this disadvantage, feature weighting methods for lazy loaming methods have been studied. Most of the existing researches, however, were focused on global feature weighting. In this research, we propose a new local feature weighting method, which we shall call CBDFW. CBDFW stores classification performance of randomly generated feature weight vectors. Then, given a new query case, CBDFW retrieves the successful feature weight vectors and designs a feature weight vector fur the query case. In the test on credit evaluation domain, CBDFW showed better classification accuracy when compared to the results of previous researches.

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Design Optimization of Axial Flow Fan Using Genetic Algorithm (유전자 알고리즘을 이용한 축류 송풍기 설계최적화)

  • Yoo, In-Tae;Ahn, Cheol-O;Lee, Sang-Hwan
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.397-403
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    • 2003
  • In an attempt to solve multiobjective optimization problems, weighted sum method is most widely used for the advantage that a designer can consider the relative significance of each object functions by weight values but it can be highly sensitive to weight vector and occasionally yield a deviated optimum from the relative weighting values designer designated because the multiobjective function has the form of simple sum of the product of the weighting values and the object functions in traditional approach. To search the design solution well agree to the designer's weighting values, we proposed new multiobjective function which is the functional of each normalized objective functions and considered to find the design solution comparing the distance between the characteristic line and the ideal optimum. In this study, proposed multiobjective function was applied to design high efficiency and low noise axial flow fan and the result shows this approach will be effective for the case that the qualify of the design can be highly affected by the designer's subjectiveness represented as weighting values in multiobjective design optimization process.

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GA based Selection Method of Weighting Matrices in LQ Controller for SVC (GA를 이용한 SVC용 LQ 제어기의 가중행렬 선정 기법)

  • 허동렬;이정필;주석민;정형환
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.6
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    • pp.40-50
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    • 2002
  • In this paper, we present a GA(Genetic Algorithm) approach to select weighting matrices of an optimal LQ(Linear Quadratic) controller for SVC(Static VAR Compensator). A SVC, one of the FACTS(Flexible AC Transmission System), constructed by a FC(Fixed Capacitor) and a TCR(Thyristor Controlled Reactor), was designed and implemented to improve the damping of a synchronous generator, as well as to control the system voltage Also, a design of LQ controller depends on choosing weighting matrices. The selection of weighting matrices which is not a trivial solution is usually carried out by trial and error. We proposed an efficient method using GA of finding weighting matrices for optimal control law. Thus, we proved the usefulness of proposed method to improve the stability of single machine-infinite bus with SVC system by eigenvalues analysis and simulation.

LQR Controller Design with Pole-Placement (극배치 특성을 갖는 LQR 제어기 설계)

  • Park, Mun-Soo;Park, Duck-Gee;Hong, Suk-Kyo;Lee, Sang-Hyuk;Park, Min-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.6
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    • pp.574-580
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    • 2007
  • This paper deals with LQR controller design method tor system having complex poles. The proposed method is capable of systematically calculating weighting matrices based on the pole's moving-range and the relational equation between closed-loop pole(s) and weighting matrices. The method moves complex poles to complex poles or two distinct real poles. This will provide much-needed functionality to apply LQR controller. The example shows the feasibility of the proposed method.