• Title/Summary/Keyword: 해공

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Past Block Matching Motion Estimation based on Multiple Local Search Using Spatial Temporal Correlation (시공간적 상관성을 이용한 국소 다중 탐색기반 고속 블록정합 움직임 추정)

  • 조영창;남혜영;이태홍
    • Journal of Korea Multimedia Society
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    • v.3 no.4
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    • pp.356-364
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    • 2000
  • Block based fast motion estimation algorithm use the fixed search pattern to reduce the search point, and are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search region we are likely to find local minima instead of the global minimum and highly rely on the initial search points. This situation is evident in the motion boundary. In this paper we define the candidate regions within the search region using the motion information of the neighbor blocks and we propose the multiple local search method (MLSM) which search for the solution throughout the candidate regions to reduce the possibilities of isolation to the local minima. In the MLSM we mark the candidate region in the search point map and we avoid to search the candidate regions already visited to reduce the calculation. In the simulation results the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary. Especially, in PSNR the proposed method obtains similar estimate accuracy with the significant reduction of search points to that of full search.

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GA-based parameter identification of DC motors (DC 모터의 GA 기반 파라미터 추정)

  • Lee, Yun-Hyung;So, Myung-Ok
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.6
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    • pp.716-722
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    • 2014
  • In order to design the speed controller of the DC motor system, firstly, parameters estimation of the system must be preceded. In this paper, we proposed the application of genetic algorithm(GA) optimization in estimating the parameters of DC motor. Estimated models are considered both first and second order models, and each estimated model is optimized by minimizing three different types of the evaluation function of GA. Also, GA is imported in comparison with estimation result of numerical analysis method because of its power in searching entire solution space with more probability of finding the global optimum. Data for parameter estimation is acquired from input and output signals of the actual experiment device and the butterworth filter also designs for removing noise in the signals. Finally comparison between real data of the actual device and estimated models is presented to indicate effectiveness and resolution of proposed identification method.

Optimal LAN Design Using a Pareto Stratum-Niche Cubicle Genetic Algorithm (PS-NC GA를 이용한 최적 LAN 설계)

  • Choi, Kang-Hee;Jung, Kyoung-Hee
    • Journal of the Korea Computer Industry Society
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    • v.6 no.3
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    • pp.539-550
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    • 2005
  • The spanning tree, which is being used the most widely in indoor wiring network, is chosen for the network topology of the optimal LAN design. To apply a spanning tree to GA, the concept of $Pr\ddot{u}fer$ numbers is used. $Pr\ddot{u}fer$ numbers can express he spanning tree in an efficient and brief way, and also can properly represent the characteristics of spanning trees. This paper uses Pareto Stratum-Niche Cubicle(PS-NC) GA by complementing the defect of the same priority allowance in non-dominated solutions of pareto genetic algorithm(PGA). By applying the PS-NC GA to the LAN design areas, the optimal LAN topology design in terms of minimizing both message delay time and connection-cost could be accomplished in a relatively short time. Numerical analysis has been done for a hypothetical data set. The results show that the proposed algorithm could provide better or good solutions for the multi-objective LAN design problem in a fairly short time.

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An Extension of Possibilistic Fuzzy C-means using Regularization (Regularization을 이용한 Possibilistic Fuzzy C-means의 확장)

  • Heo, Gyeong-Yong;NamKoong, Young-Hwan;Kim, Seong-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.1
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    • pp.43-50
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    • 2010
  • Fuzzy c-means (FCM) and possibilistic c-means (PCM) are the two most well-known clustering algorithms in fuzzy clustering area, and have been applied in many applications in their original or modified forms. However, FCM's noise sensitivity problem and PCM's overlapping cluster problem are also well known. Recently there have been several attempts to combine both of them to mitigate the problems and possibilistic fuzzy c-means (PFCM) showed promising results. In this paper, we proposed a modified PFCM using regularization to reduce noise sensitivity in PFCM further. Regularization is a well-known technique to make a solution space smooth and an algorithm noise insensitive. The proposed algorithm, PFCM with regularization (PFCM-R), can take advantage of regularization and further reduce the effect of noise. Experimental results are given and show that the proposed method is better than the existing methods in noisy conditions.

A Genetic Algorithm Based Learning Path Optimization for Music Education (유전 알고리즘 기반의 음악 교육 학습 경로 최적화)

  • Jung, Woosung
    • Journal of the Korea Convergence Society
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    • v.10 no.2
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    • pp.13-20
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    • 2019
  • For customized education, it is essential to search the learning path for the learner. The genetic algorithm makes it possible to find optimal solutions within a practical time when they are difficult to be obtained with deterministic approaches because of the problem's very large search space. In this research, based on genetic algorithm, the learning paths to learn 200 chords in 27 music sheets were optimized to maximize the learning effect by balancing and minimizing learner's burden and learning size for each step in the learning paths. Although the permutation size of the possible learning path for 27 learning contents is more than $10^{28}$, the optimal solution could be obtained within 20 minutes in average by an implemented tool in this research. Experimental results showed that genetic algorithm can be effectively used to design complex learning path for customized education with various purposes. The proposed method is expected to be applied in other educational domains as well.

Improved Density-Independent Fuzzy Clustering Using Regularization (레귤러라이제이션 기반 개선된 밀도 무관 퍼지 클러스터링)

  • Han, Soowhan;Heo, Gyeongyong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.1
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    • pp.1-7
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    • 2020
  • Fuzzy clustering, represented by FCM(Fuzzy C-Means), is a simple and efficient clustering method. However, the object function in FCM makes clusters affect clustering results proportional to the density of clusters, which can distort clustering results due to density difference between clusters. One method to alleviate this density problem is EDI-FCM(Extended Density-Independent FCM), which adds additional terms to the objective function of FCM to compensate for the density difference. In this paper, proposed is an enhanced EDI-FCM using regularization, Regularized EDI-FCM. Regularization is commonly used to make a solution space smooth and an algorithm noise insensitive. In clustering, regularization can reduce the effect of a high-density cluster on clustering results. The proposed method converges quickly and accurately to real centers when compared with FCM and EDI-FCM, which can be verified with experimental results.

Strength of Improved Soil on the Work-conditions of Deep Mixing Method (시공조건에 따른 심층혼합처리 개량체의 강도에 관한 연구)

  • Lee, Kwang-Yeol;Yoon, Sung-Tai;Kim, Sung-Moo;Han, Woo-Sun
    • Journal of the Korean Geotechnical Society
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    • v.23 no.7
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    • pp.99-104
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    • 2007
  • The deep soil mixing, on ground modification technique, has been used for many diverse applications including building and bridge foundations, port and harbor foundations, retaining structures, liquefaction mitigation, temporary support of excavation and water control. This method has the basic objective of finding the most efficient and economical method for mixing cement with soil to secure settlements through improvement of stability on soft ground. In this research, the experiments were conducted on a laboratory scale with the various test conditions of mixing method; the angle of mixing wing, mixing speed. Strength and shapes of improved soil of these test conditions of deep mixing method were analysed. From the study, it was found that the mixing conditions affect remarkably to the strength and shapes of improved soils.

Ecological Studios on the Bark Beetles on Plum and Apricot (자두와 살구나무에 기생하는 나무좀의 생태에 관한 연구)

  • Yoon J. K.;Kim K. C.;Cheon S. J.;Kim Y. S.
    • Korean journal of applied entomology
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    • v.21 no.2 s.51
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    • pp.78-86
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    • 1982
  • The ecological studies were conducted to identify some bark-beetles on apricot and plum trees in Jeonnam province. Harmful bark-beetles caught from apricot and plum trees were identified as Scolytus seulensis. Xyleborus atratus., X. germanus, X. rubricollis and X. saxeseni. The seoul barkbeetle emerged during the period from early May to late October $1980\~1981$, it happens twice in a year, with the peak July 10 and August 25 in 1950, July 15 and August 20 in 1981. A daily peak emerged for adults was at 11 AM to 1 PM. Distribution of holes on the apricot stems varied; more than 100 holes per meter in Henderson (Apricot) and Y-49057 (Apricot), 12 holes per meter in Derbyroyal (Apricot). Comparatively more holes were found in the European variety, and the cardinal distribution was in the order of east, south, west and north. The longer the longth of the mother-gallery, the greater number of egg-gallery found. Optimum temperature for mating was $27^{\circ}C$. The time for mating was longer during May-June than July-August. The fruit weight of damaged plum tree reached 12.25g around four weeks after flowering; where as that of normal tree increased up to 63.5g at harvest time. The natural enemy of the seoul bark beetle was Eurytoma sp. They were found as mature larva or pupa and they emerged from early May to the middle of June. Adult longevity was about a week.

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A Study on the Damage of Pine Stand by Snowfall (항설(降雪)에 의(依)한 소나무 임분(林分)의 피해(被害)에 관(關)한 연구(硏究))

  • Ma, Ho Seop;Kang, Wee Pyeong;Kim, Jai Saing
    • Journal of Korean Society of Forest Science
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    • v.73 no.1
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    • pp.63-69
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    • 1986
  • In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

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