• 제목/요약/키워드: Initial set

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Development of a Core Set of Korean Soybean Landraces [Glycine max(L.) Merr.]

  • Cho, Gyu-Taek;Yoon, Mun-Sup;Lee, Jeong-Ran;Baek, Hyung-Jin;Kang, Jung-Hoon;Kim, Tae-San;Paek, Nam-Chon
    • Journal of Crop Science and Biotechnology
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    • 제11권3호
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    • pp.157-162
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    • 2008
  • A total of 2,765 accessions were used as the initial set having both seed coat color and 100-seed weight data. As a result of molecular profiling using six SSR markers followed by stratification based on their usages, 335 accessions(12.1%) were selected by clustering based on UPGMA. Since 75 out of 335 accessions were mixed in phenotypic traits as a result of characterization, 260 accessions were finally set as a core set. This core set revealed nearly the same diversity compared with the other results on morphological traits of Korean soybean landraces. In total, 115 alleles(19.2 alleles per locus) were detected in the initial set and 79 alleles(13.2 alleles per locus) were detected in the core set. All 30 major alleles were present in the initial set and in the core set as well. In allele coverage, the core set was 71.4% of the initial set. These comparisons of number of alleles, gene diversity and coverage indicated that the core set represented the entire set well.

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능동적 학습을 위한 군집기반 초기훈련집합 선정 (Selection of An Initial Training Set for Active Learning Using Cluster-Based Sampling)

  • 강재호;류광렬;권혁철
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제31권7호
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    • pp.859-868
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    • 2004
  • 본 논문에서는 능동적 학습이 보다 적은 수의 훈련예제로도 높은 학습성능을 달성할 수 있도록 군집화기법을 이용하여 초기훈련집합을 선정하는 방안을 제안한다. 본 제안 방안은 유사한 예제들보다는 다양한 예제들로 그리고 특수한 예제들보다는 보편적인 예제들로 구성한 집합이 학습에 유리할 것이라는 가정을 바탕으로, 먼저 k-means 군집화 기법으로 예제들을 군집화한 후, 각 군집을 가장 잘 표현하는 대표예제로 개별 군집의 중심점과 가장 가까운 예제를 선정하여 초기훈련집합을 구성한다. 또한 개별 군집의 중심점을 가상의 예제로 가정하여, 이와 연관된 대표예제의 카테고리를 부여함으로써 추가의 훈련예제로 활용하는 방안을 함께 제안한다. 여러 문서 분류 문제를 대상으로 실험한 결과, 본 제안 방안으로 선정한 초기훈련집합에서 출발한 능동적 학습이 임의로 선정한 초기훈련집합에서 출발한 경우에 비해 보다 적은 수의 훈련예제로도 동등한 성능을 달성할 수 있음을 확인하였다.

Topological Derivative를 이용한 선형 구조물의 레벨셋 기반 형상 최적 설계 (Level Set Based Shape Optimization of Linear Structures Using Topological Derivatives)

  • 하승현;김민근;조선호
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.299-306
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    • 2006
  • Using a level set method and topological derivatives, a topological shape optimization method that is independent of an initial design is developed for linearly elastic structures. In the level set method, the initial domain is kept fixed and its boundary is represented by an implicit moving boundary embedded in the level set function, which facilitates to handle complicated topological shape changes. The 'Hamilton-Jacobi (H-J)' equation and computationally robust numerical technique of 'up-wind scheme' lead the initial implicit boundary to an optimal one according to the normal velocity field while minimizing the objective function of compliance and satisfying the constraint of allowable volume. Based on the asymptotic regularization concept, the topological derivative is considered as the limit of shape derivative as the radius of hole approaches to zero. The required velocity field to update the H -J equation is determined from the descent direction of Lagrangian derived from optimality conditions. It turns out that the initial holes is not required to get the optimal result since the developed method can create holes whenever and wherever necessary using indicators obtained from the topological derivatives. It is demonstrated that the proper choice of control parameters for nucleation is crucial for efficient optimization process.

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진화론적 데이터 입자에 기반한 퍼지 집합 기반 퍼지 추론 시스템의 최적화 (Optimization of Fuzzy Set-based Fuzzy Inference Systems Based on Evolutionary Data Granulation)

  • 박건준;이동윤;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.343-345
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    • 2004
  • We propose a new category of fuzzy set-based fuzzy inference systems based on data granulation related to fuzzy space division for each variables. Data granules are viewed as linked collections of objects(data, in particular) drawn together by the criteria of proximity, similarity, or functionality. Granulation of data with the aid of Hard C-Means(HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polyminial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms(GAs) and the least square method. Numerical example is included to evaluate the performance of the proposed model.

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적외선 영상에서 표적 추적을 위한 신호세기 기반 초기 유효게이트 설정 방법 (Setting an Initial Validation Gate based on Signal Intensity for Target Tracking in IR Image Sequences)

  • 양유경;김지은;이부환
    • 한국군사과학기술학회지
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    • 제17권1호
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    • pp.108-114
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    • 2014
  • This paper describes a method to set an intensity-based initial validation gate for tracking filter while preserves the ability of tracking a target with maximum speed. First, we collected real data set of signal versus distance of an airplane target. And at each data point, we computed maximum distance the target can move. And a function is modeled to expect the maximum moving pixels on the lateral direction based on the intensity of the detected target in IR image sequence. The initial prediction error covariance can be computed using this function to decide the size of the initial validation gate. The simulation results show the proposed method can set the appropriate initial validation gates to track the targets with the maximum speed.

비국소 초기 조건을 갖는 퍼지 미분 시스템에 대한 제어가능성 (On the controllability of fuzzy differential systems with nonlocal initial conditions)

  • 강점란;정두환;권영철
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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    • pp.272-275
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    • 2002
  • In this paper, we find the controllability conditions for the following fuzzy differential systems (equation omitted) where A(t), B(t) are continuous matrices, g is given function, U(t) is fuzzy set and target X$^1$ is fuzzy set.

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원쌍대 내부점기법에서 초기해 선정과 중심화 힘을 이용한 개선 방향의 수정 (Finding an initial solution and modifying search direction by the centering force in the primal-dual interior point method)

  • 성명기;박순달
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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    • pp.530-533
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    • 1996
  • This paper deals with finding an initial solution and modifying search direction by the centrering force in the predictor-corrector method which is a variant of the primal-dual barrier method. These methods were tested with NETLIB problems. Initial solutions which are located close to the center of the feasible set lower the number of iterations, as they enlarge the step length. Three heuristic methods to find such initial solution are suggested. The new methods reduce the average number of iterations by 52% to at most, compared with the old method assigning 1 to initial valurs. Solutions can move closer to the central path fast by enlarging the centering force in early steps. It enlarge the step length, so reduces the number of iterations. The more effective this method is the closer the initial solution is to the boundary of the feasible set.

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신경망 학습앙상블에 관한 연구 - 주가예측을 중심으로 - (A Study on Training Ensembles of Neural Networks - A Case of Stock Price Prediction)

  • 이영찬;곽수환
    • 지능정보연구
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    • 제5권1호
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    • pp.95-101
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    • 1999
  • In this paper, a comparison between different methods to combine predictions from neural networks will be given. These methods are bagging, bumping, and balancing. Those are based on the analysis of the ensemble generalization error into an ambiguity term and a term incorporating generalization performances of individual networks. Neural Networks and AI machine learning models are prone to overfitting. A strategy to prevent a neural network from overfitting, is to stop training in early stage of the learning process. The complete data set is spilt up into a training set and a validation set. Training is stopped when the error on the validation set starts increasing. The stability of the networks is highly dependent on the division in training and validation set, and also on the random initial weights and the chosen minimization procedure. This causes early stopped networks to be rather unstable: a small change in the data or different initial conditions can produce large changes in the prediction. Therefore, it is advisable to apply the same procedure several times starting from different initial weights. This technique is often referred to as training ensembles of neural networks. In this paper, we presented a comparison of three statistical methods to prevent overfitting of neural network.

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COMPLETE PROLONGATION AND THE FROBENIUS INTEGRABILITY FOR OVERDETERMINED SYSTEMS OF PARTIAL DIFFERENTIAL EQUATIONS

  • Cho, Jae-Seong;Han, Chong-Kyu
    • 대한수학회지
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    • 제39권2호
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    • pp.237-252
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    • 2002
  • We study the compatibility conditions and the existence of solutions or overdetermined PDE systems that admit complete prolongation. For a complete system of order k there exists a submanifold of the ($\kappa$-1)st jet space of unknown functions that is the largest possible set on which the initial conditions of ($\kappa$-1)st order may take values. There exists a unique solution for any initial condition that belongs to this set if and only if the complete system satisfies the compatibility conditions on the initial data set. We prove by applying the Frobenius theorem to a Pfaffian differential system associated with the complete prolongation.

측정된 점데이터 기반 삼각형망 곡면 메쉬 모델의 국부적 자동 수정 (Automatic Local Update of Triangular Mesh Models Based on Measurement Point Clouds)

  • 우혁제;이종대;이관행
    • 한국CDE학회논문집
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    • 제11권5호
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    • pp.335-343
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    • 2006
  • Design changes for an original surface model are frequently required in a manufacturing area: for example, when the physical parts are modified or when the parts are partially manufactured from analogous shapes. In this case, an efficient 3D model updating method by locally adding scan data for the modified area is highly desirable. For this purpose, this paper presents a new procedure to update an initial model that is composed of combinatorial triangular facets based on a set of locally added point data. The initial surface model is first created from the initial point set by Tight Cocone, which is a water-tight surface reconstructor; and then the point cloud data for the updates is locally added onto the initial model maintaining the same coordinate system. In order to update the initial model, the special region on the initial surface that needs to be updated is recognized through the detection of the overlapping area between the initial model and the boundary of the newly added point cloud. After that, the initial surface model is eventually updated to the final output by replacing the recognized region with the newly added point cloud. The proposed method has been implemented and tested with several examples. This algorithm will be practically useful to modify the surface model with physical part changes and free-form surface design.