• 제목/요약/키워드: Estimation possibility

검색결과 573건 처리시간 0.027초

Support Vector Machine for Interval Regression

  • Hong Dug Hun;Hwang Changha
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2004년도 학술발표논문집
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    • pp.67-72
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    • 2004
  • Support vector machine (SVM) has been very successful in pattern recognition and function estimation problems for crisp data. This paper proposes a new method to evaluate interval linear and nonlinear regression models combining the possibility and necessity estimation formulation with the principle of SVM. For data sets with crisp inputs and interval outputs, the possibility and necessity models have been recently utilized, which are based on quadratic programming approach giving more diverse spread coefficients than a linear programming one. SVM also uses quadratic programming approach whose another advantage in interval regression analysis is to be able to integrate both the property of central tendency in least squares and the possibilistic property In fuzzy regression. However this is not a computationally expensive way. SVM allows us to perform interval nonlinear regression analysis by constructing an interval linear regression function in a high dimensional feature space. In particular, SVM is a very attractive approach to model nonlinear interval data. The proposed algorithm here is model-free method in the sense that we do not have to assume the underlying model function for interval nonlinear regression model with crisp inputs and interval output. Experimental results are then presented which indicate the performance of this algorithm.

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Performance Analysis of MUSIC-Based Jammer DOA Estimation Technique for a Misaligned Antenna Array

  • Park, Kwansik;Seo, Jiwon
    • Journal of Positioning, Navigation, and Timing
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    • 제9권1호
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    • pp.7-13
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    • 2020
  • As a countermeasure against the threat of jamming which can disrupt operation of the Global Positioning System (GPS) receivers, various kinds of technique to estimate the Direction-Of-Arrivals (DOAs) of incoming jamming signals have been widely studied, and among them, the MUltiple SIgnal Classification (MUSIC) algorithm is known to provide very high resolution. However, since the previous studies regarding the MUSIC algorithm does not consider the orientation of each antenna element of antenna arrays, there is a possibility that DOA estimation performance degrades in the case of a misaligned antenna array whose antenna elements are not oriented along the same direction. As an effort to solve this problem, there exists a previous work which presents an MUSIC-based method for DOA estimation. However, the error between the real and measured values of each antenna orientation is not taken into consideration. Therefore, in this paper, the effect of the aforementioned error on the DOA estimation performance in the case of a misaligned antenna array is analyzed by simulations.

DSM Monitoring을 위한 확산 모델의 계수 추정 (Parameter estimation of the Diffusion Model for Demand Side Management Monitoring System)

  • 최청훈;정현수;김진오
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.1073-1075
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    • 1998
  • This paper presents the method of parameter estimation of diffusion model for monitoring Demand-Side Management Program. Bass diffusion model was applied in this paper, which has different values according to parameters ; coefficients of innovation, imitation and potential adopters. Though it is very important to estimate three parameter, there are no empirical results in practice. Thus, this paper presents the method of parameter estimation in case of few data with constraints to reduce the possibility of bad estimation. The constraints are empirical results or expert's decision. Case studies show the diffusion curves of high-efficient lighting and also forecasting of the peak value for power demand considering diffusion of high-efficient lighting, the feedback and least-square parameter estimation method used in this paper enable us to evaluate the status and forecasting of the effect of DSM program.

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견실한 H$\infty$필터를 이용한 기동표적의 추적 (Tracking maneuvering target using robust H$\infty$filter)

  • 김준영;유경상;권오규
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.426-429
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    • 1997
  • This paper proposes a robust H$_{\infty}$ tracking filter to improve the unacceptable target tracking performance for systems with parameter uncertainties. Also, we use here the input estimation approach to account for the possibility of maneuver. Simulation results show that the robust H$_{\infty}$ tracking filter which is proposed here to solve the systems with all system parameter uncertainties, has a good tracking performance for a maneuvering target tracking problem.m.

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MUSIC 알고리듬을 이용한 공간파 신호의 도래각 추정 (The Estimation of Directions of Arrival of Multiple Sky Waves Using MUSIC Algorithm)

  • 채종석;박형래;이혁재;박한규
    • 대한전자공학회논문지
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    • 제25권9호
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    • pp.1134-1140
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    • 1988
  • In this paper, the theory of superresolution algorithms for estimation of directions of arrival of signals using eigen-structure analysis (mainly MUSIC algorithm)is described. Also, we apply MUSIC algorithm to circularly disposed antenna system, and simulate the angular resolution according to relative azimuth difference, S/N ratio, number of snapshots, so that we confirm the possibility of applications of MUSIC algorithm to sky wave in real situations.

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근입깊이에 따른 콘크리트 교각의 동특성 변화에 관한 실험적 연구 (An Experimental Analysis on the Pier Dynamic Property Change with Penetration Depths)

  • 박병철;박승범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.655-658
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    • 2004
  • This study was performed to verify the possibility of the integrity estimation of the bridge substructure focusing on the dynamic property change of concrete pier with penetration depths using experimental modal analysis. As a result of the impact vibration test, it is found that scour reduces the stiffness of the foundation, and measurement the accelerance residue and natural frequency can be used for the estimation of the integrity index.

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Pre-Evaluation for Detecting Abnormal Users in Recommender System

  • Lee, Seok-Jun;Kim, Sun-Ok;Lee, Hee-Choon
    • Journal of the Korean Data and Information Science Society
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    • 제18권3호
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    • pp.619-628
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    • 2007
  • This study is devoted to suggesting the norm of detection abnormal users who are inferior to the other users in the recommender system compared with estimation accuracy. To select the abnormal users, we propose the pre-filtering method by using the preference ratings to the item rated by users. In this study, the experimental result shows the possibility of detecting the abnormal users before the process of preference estimation through the prediction algorithm. And It will be possible to improve the performance of the recommender system by using this detecting norm.

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퍼지 논리를 이용한 웨이퍼의 사이즈 추정 알고리즘

  • 권오진;최성주;조현찬;김광선
    • 한국반도체및디스플레이장비학회:학술대회논문집
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    • 한국반도체및디스플레이장비학회 2003년도 춘계학술대회 발표 논문집
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    • pp.74-79
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    • 2003
  • This paper is concerned with the estimation of a wafer part in grasping system. The estimation of a wafer size in grasping system is very important because a wafer must be placed in accurate position. The accurate information of a wafer size should be forward to Robot in order to place a wafer in accurate position. So in this paper, we decide the size of a wafer with Fuzzy Logic and consider the possibility of this method by simulation.

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풍수해 피해규모 파악을 위한 위성영상의 활용방안 연구 (A study on the estimation of damage by storm and flood using satellite imagery)

  • 손홍규;윤공현;이정빈;진경혁
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2007년도 춘계학술발표회 논문집
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    • pp.111-114
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    • 2007
  • One of future remote sensing techniques for the estimation of damage by storm and flood is the extraction of water area, which could be the basis of measuring the damage by storm and flood and estimate restoration cost. This paper introduces an approach to damage estimation using satellite Image. The project site was Ansung area and a set of Radarsat-1 SAR image at 6.25m resolution was used for the test. Authors investigated methods of SAR image processing such as shadow-effect removal, orthorectification of SAR image and calculation of damage area by flood. Consequetly, this study showed that technique improvement of image processing and the best of result for extracting water area. Also, found the new possibility of damage estimation using satellite image.

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