• Title/Summary/Keyword: Region Partition

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MEASURE INDUCED BY THE PARTITION OF THE GENERAL REGION

  • Chang, Joo Sup;Kim, Byoung Soo
    • Korean Journal of Mathematics
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    • v.21 no.3
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    • pp.237-246
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    • 2013
  • In this paper we first consider the partition of the general region made by the monotonically increasing and continuous function and then obtain the measure from the partition of the region. The results obtained here is a little bit different from the previous results in [1, 2, 3] and finally we discuss the difference.

An Experiment and Numerical Analysis of Mixed Convection in a Rectangular Space with Variable Partition (가변 격판을 갖는 사각공간 내의 혼합대류에 대한 실험과 수치해석)

  • 이광성;신재호;이중섭;정한식;정효민
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.12
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    • pp.1230-1235
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    • 2001
  • The laminar convection heat transfer in a ventilated space with various horizontal partitions was studied numerically and experimentally. The experimental results by holographic interferometer showed good agreements with the numerical results. For the numerical study, the governing equations were solved by using a finite volume method for $46.6\leqRe\leq1332,\;1460\leqGr\leql1585$, Pr=0.71 and the variations of partition lengths. The isotherms and velocity vectors have been represented for various parameters. As the length of partition increases, the convection heat transfer decreases. Based on the numerical data, a correlation was obtained for the dimensionless mean Nusselt number in terms of $Gr/Re^2$. In the region of $Gr/Re^2$<1, the mean Nusselt number was very small, but in the region of $Gr/Re^2\geq1$, the mean Nusselt number was constant.

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Region-Based Video Object Extraction Using Potential of frame - Difference Energies (프레임차 에너지의 전위차를 이용한 영역 기반의 비디오 객체 추출)

  • 곽종인;김남철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.3A
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    • pp.268-275
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    • 2002
  • This paper proposes a region-based segmentation algorithm fur extracting a video object by using the cost of potential of frame-difference energies. In the first step of a region-based segmentation using spatial intensity, each frame is segmented into a partition of homogeneous regions finely so that each region does not contain the contour of a video object. The fine partition is used as an initial partition for the second step of spatio-temporal segmentation. In spatio-temporal segmentation, the homogeneity cost for each pair of adjacent regions is computed which reflects the potential between the frame-difference energy on the common contour and the frame-difference energy of the lower potential region of the two. The pair of adjacent regions whose cost is minimal then is searched. The two regions of minimum cost ale merged, which result in updating the partition. The merging is recursively performed until only the contours remain which have Same difference energies of high potential. In the fecal step of post-processing, the video object is extracted removing the contours inside the object.

Enhanced Region Partitioning Method of Non-perfect nested Loops with Non-uniform Dependences

  • Jeong Sam-Jin
    • International Journal of Contents
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    • v.1 no.1
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    • pp.40-44
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    • 2005
  • This paper introduces region partitioning method of non-perfect nested loops with non-uniform dependences. This kind of loop normally can't be parallelized by existing parallelizing compilers and transformations. Even when parallelized in rare instances, the performance is very poor. Based on the Convex Hull theory which has adequate information to handle non-uniform dependences, this paper proposes an enhanced region partitioning method which divides the iteration space into minimum parallel regions where all the iterations inside each parallel region can be executed in parallel by using variable renaming after copying.

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Determination of Regulator Parameters and Transient Analysis of Modified Self-commutating CSI-fed IM Drive

  • Pandey, A.K.;Tripathi, S.M.
    • Journal of Electrical Engineering and Technology
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    • v.6 no.1
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    • pp.48-58
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    • 2011
  • In this paper, an attempt has been made to design the current and speed proportional and integral (PI) regulators of self-commutating current source inverter-fed induction motor drive having capacitors at the machine end and to investigate the transient performance of the same for step changes in reference speed. The mathematical model of the complete drive system is developed in closed loop, and the characteristic equations of the systems are derived using perturbation about steady-state operating point in order to develop the characteristic equations. The D-partition technique is used for finding the stable region in the parametric plane. Frequency scanning technique is used to confirm the stability region. Final selection of the regulator parameters is done by comparing the transient response of the current and speed loops for step variations in reference. The performance of the drive is observed analytically through MATLAB simulation.

Convective Heat Transfer in Ventilated Space wit=h Various Partitions

  • Bae, Kangyoul;Chung, Hanshik;Jeong, Hyomin
    • Journal of Mechanical Science and Technology
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    • v.16 no.5
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    • pp.676-682
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    • 2002
  • The laminar convective heat transfer in ventilated space with various horizontal partitions was studied numerically and experimentally For the numerical study, the governing equations were solved by using a finite volume method for various numbers Re, Gr, Pr and partition numbers. The experimental study was conducted by using a holographic interferometer. The isotherms and velocity vectors have been presented for various parameters. As the number and length of partition increased, convective heat transfer decreased. Based on the numerical data, correlation equations were obtained for the mean Nusselt number in term of Gr/Re$^2$. In the region of Gr/Re$^2$$\leq$ 1, the mean Nusselt number was small, but in the region of Gr/Re$^2$> 1, the mean Nusselt number was constant.

Design of VML-based Game System for Dynamic Load Balancing (동적 부하 분산을 위한 VML 기반 게임 시스템 설계)

  • Lee, Jeong-Jin;Won, Dong-Kee;Hwang, Ho-Jeon;Doo, Gil-Su;Kim, Beob-Kyun;An, Dong-Un;Chung, Seung-Jong
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.303-305
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    • 2005
  • In MMORPG, gamers can engage in a variety of activities with other players from all over the world. So, this kind of games has unprecedented heavy load. There are so many kind of method to balance the load of MMORPG. But. many of them are not adaptable to dynamic load variation. In this paper, we propose a dynamic map-partition method based on VML. By use of dynamic map-partition based on VML, we can easily adapt to dynamic load variation. And by changing VML. we can manage field servers within game system.

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Method of Human Detection using Edge Symmetry and Feature Vector (에지 대칭과 특징 벡터를 이용한 사람 검출 방법)

  • Byun, Oh-Sung
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.8
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    • pp.57-66
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    • 2011
  • In this paper, it is proposed for algorithm to detect human efficiently using a edge symmetry and gradient directional characteristics in realtime by the feature extraction in a single input image. Proposed algorithm is composed of three stages, preprocessing, region partition of human candidates, verification of candidate regions. Here, preprocessing stage is strong the image regardless of the intensity and brightness of surrounding environment, also detects a contour with characteristics of human as considering the shape features size and the condition of human for characteristic of human. And stage for region partition of human candidates has separated the region with edge symmetry for human and size in the detected contour, also divided 1st candidates region with applying the adaboost algorithm. Finally, the candidate region verification stage makes excellent the performance for the false detection by verifying the candidate region using feature vector of a gradient for divided local area and classifier. The results of the simulations, which is applying the proposed algorithm, the processing speed of the proposed algorithms is improved approximately 1.7 times, also, the FNR(False Negative Rate) is confirmed to be better 3% than the conventional algorithm which is a single structure algorithm.

A Partitioning Method Recucing the Number of Tool Retractions in Zigzag Pocket Machining (지그재그 포켓 가공에서 공구후퇴 횟수를 줄이기 위한 영역 분할법)

  • 서경천;김재정
    • Korean Journal of Computational Design and Engineering
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    • v.6 no.4
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    • pp.215-221
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    • 2001
  • In the zigzag milling of a pocket having islands, tool retraction is one of the primary factors that decrease productivity. Therefore, tool path with minimum number of tool retraction has been needed. Most researches about this topic have been concentrated on obtaining the optimum solution formulated through the geometric reasoning off pocket. Recently, several attempts were made to simplify this problem into region partitioning in order to get the numerically expressed minimum solution. In this research, a method reducing the number of tool retractions extended from existing region partitioning is provided. Applying the segment that is normal to the reference direction of zigzag milling, region partitioning is carried out and structural elements of the region are searched via graphs of islands and characteristic points. Through the processes presented, the number of region partitioned is less than that of existing processes.

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An Experimental Study on the Transmission Loss of Perforated Tube Mufflers (다공관 소음기의 투과손실에 관한 실험적 연구)

  • 김찬묵;사종성;방극호
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.346-352
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    • 2002
  • This paper is the experimental study to estimate the influence of various design parameters on the performance of mufflers with perforated tubes and through-flow partitions. Muffler types considered in the present work include through-flow chamber, through-flow chamber with partition, and cross-flow chamber. The influences of the design parameters on the performance of the mufflers can be outlined as follows. In the case of the through-f]ow type mufflers, increasing the tube thickness and the hole diameter of the perforated tubes does not change the maximum value of the transmission loss but decrease the cutoff frequency. In the case of the through-flow with partitions type mufflers, it is shown that combining a fe w short chambers and long chambers can modify the frequency locations of the resonance frequencies to optimize the performance of the mufflers. For the case of the cross-flow type mufflers, it is shown that the transmission loss of the mufflers is mainly affected by the lower porosity when the porosities are different in both sides of the plug. Overall, it is shown that performance of the through-flow type with partition type mufflers is excellent in the lower frequency region, where the cross-flow type mufflers have better performance in the higher frequency region.

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