• Title/Summary/Keyword: Block packing

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Efficient Block Packing to Minimize Wire Length and Area

  • Harashima, Katsumi;Ootaki, Yousuke;Kutsuwa, Toshirou
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1539-1542
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    • 2002
  • In layout of LSI and PWB, block pack- ing problem is very important in order to reduce chip area. Sequence-pair is typical one of conventional pack- ing method and can search nearly-optimal solution by using Simulated Annealing(SA). SA takes huge computation time due to evaluating of various packing results. Therefore, Sequence-pair is not effective enough for fast layout evaluation including estimation of wire length and rotation of every blocks. This paper proposes an efficient block packing method to minimize wire length and chip area. Our method searches an optimal packing efficient- ly by using a cluster growth algorithm with changing the most valuable packing score on packing process.

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Computer Simulation of Three Dimensional Particle Packing (콜로이드 입자의 3차원적인 적층에 대한 컴퓨터 시뮬레이션)

  • ;David M. Martin
    • Journal of the Korean Ceramic Society
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    • v.34 no.9
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    • pp.979-985
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    • 1997
  • The three-dimensional particle packing process is simulated using Lahey FORTRAN 90 as a programming language running on a personal computer. Particle clusters constructed with rearrangement which occurs during packing have higher average coordination number and packing density than particle clusters rearranged after packing. Rearranging particles can not completely block other particles from entering pore volume in 3-dimensional packing unlike in 2-dimensional packing. It is found that there is a region of instability where lower packing density results from the destruction of the ordered packing.

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Analysis of freshness of rice depending on packing materials using MANOVA (다변량 분산분석을 이용한 포장 재질에 따른 쌀의 신선도 분석)

  • Kim, Seong-Ju
    • The Korean Journal of Applied Statistics
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    • v.29 no.7
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    • pp.1421-1428
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    • 2016
  • This paper concerns the freshness of rice depending on packing materials using MANOVA. Freshness of rice is measured in terms of moisture content and rice flavor. Ordinary paper and charcoal-coated paper are compared as packing materials. Storing places are considered as a block. The bivariate observations of moisture content and the rice flavor are compared using MANOVA for a completely randomized block design. It is observed that there is a significant difference between ordinary paper and charcoal-coated paper. Therefore we apply ANOVA for moisture content and rice flavor, respectively. Significant differences are observed for the moisture content but not for the rice flavor.

Algorithm for Block Packing of Main Memory Allocation Problem (주기억장치 할당 문제의 블록 채우기 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.6
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    • pp.99-105
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    • 2022
  • This paper deals with the problem of appropriately allocating multiple processors arriving at the ready queue to the block in the user space of the main memory is divided into blocks of variable size at compilation time. The existing allocation methods, first fit(FF), best fit(BF), worst fit(WF), and next fit(NF) methods, had the disadvantage of waiting for a specific processor because they failed to allocate all processors arriving at the ready queue. The proposed algorithm in this paper is a simple block packing algorithm that allocates as many processors as possible to the largest block by sorting the size of the partitioned blocks(holes) and the size of the processor in the ready queue in descending order. The application of the proposed algorithm to nine benchmarking experimental data showed the performance of allocating all processors while having minimal internal fragment(IF) for all eight data except one data in which the weiting processor occurs due to partition errors.

A basic study on development of photocatalystic block to purify polluted air (대기정화 광촉매블록 개발에 관한 기초적 연구)

  • 김현우;정봉원;박준영;최영준;김화중
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.1117-1122
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    • 2001
  • This study is to investigate application to the load packing or block with photocatalystic which has the characteristics absorption and removal for NOx, which is mainly generated from plant or car, which can be resolved by actions of light. Therefor a basic study was carried out to maximize the photocatalystic block for elimination of NOx.

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Microstructure and properties of HQEE-based PU (HQEE-based PU의 미세구조 및 특성)

  • 이정상;이한섭
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.350-351
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    • 2003
  • Polyurethane은 물리적, 화학적 성질이 매우 다른 두 segment(hard/soft)로 이루어진 block copolymer로서 hard segment의 화학적 구조가 hard segment의 packing정도에 영향을 미쳐, PU의 미세상분리 현상을 결정하며 결과적으로 PU의 물리적 성질에 큰 영향을 미치게 된다$^1$. 본 연구에서는 hard segment의 packing을 향상시켜 PU은 열적 기계적 특성을 향상시키기 위하여 방향족환으로 구성되어 있어 aromatic diol의 일종인 hydroxyquinone-di-(beta-hydroxyl)ether(HQEE)를 chain extender로 사용하여 PU를 합성하였다. (중략)

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A Study on the Repair Welding Methods for Cylinder Block of Diesel Engines (디젤기관 실린더 블록의 보수용접법에 대한 연구)

  • Kim, Jong-Ho;Cho, Sang-Myung
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.287-288
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    • 2006
  • Cracks on the cylinder block of diesel engines will often happen due to cyclic load and thermal stress. According to the Classification Societies' rules, welding repairs of cylinder block made of cast irons are generally not permitted. However, such welding repairs became inevitable taking enormous cost and time for their renewal into consideration. In this study repair welding methods for the cylinder blocks, made of gray cast irons were reviewed and the tests of their welds were carried out in order to purpose the repair welding methods of packing seat and o-ring seat of cylinder block and apply them to the practice. It is concluding remarks that the suspected crack by a magnetic particle test due to different magnetic permeability can be identified, which are not associated with a mechanical discontinuity.

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A Method for Determining Molecular Weights of Block Copolymers by Gel Permeation Chromatography

  • Sohn, Jeong-In;Ree, Tai-Kyue
    • Bulletin of the Korean Chemical Society
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    • v.5 no.4
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    • pp.140-145
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    • 1984
  • A theory is given for determining the molecular weights of block copolymers from the experimental elution volume in GPC. Interaction effect between a sample of block copolymer and a column packing material as well as the size effect are separately considered for the first time applying the partial exclusion mechanism proposed by Dawkins. The molecular weight determination shows 6${\%}$ standard-deviation from the molecular weights measured by an osmometric method for eight block copolymers, which is much more improved result than other methods, e.g., the universal plot method (13 ${\%}$) and the Runyon's method (12 ${\%}$). The reason which explains the better result is that our theory takes into account the interaction effect correctly.

Call Admission Schemes for Multimedia Services in CDMA Cellular Systems (셀룰라 시스템에서 멀티미디어 서비스를 위한 호 수락제어 기법 연구)

  • Choi Sung-Gu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.3B
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    • pp.232-238
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    • 2006
  • We propose a novel call admission control scheme which improves the handoff drop and the new call block probabilities of high priority services, minimizing the negative impact on low priority services, in multimedia service cellular networks. This paper proposes three schemes to solve this problem; the packing scheme in which available channels of a cell distributed to each frequency channel are concentrated on one frequency channel and a high transmission rate service is assigned to the frequency channel; the queuing scheme in which the queue is used for high transmission rate calls; and the power reallocation scheme in which the power assigned to calls under service is temporarily reduced and a high transmission rate service is allowed. The simulation results revealed that our scheme improved the drop and the block probabilities of the high priority services compared with the conventional scheme.

Floorplanning with Obstacles(Preplaced Block) based on CBL (고정블록을 포함한 CBL 기반 평면계획)

  • Kang, Sang-Ku;Rim, Chong-Suck
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.3
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    • pp.217-230
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    • 2009
  • In this paper we propose a new CBL-based floorplan method that accommodates pre-placed blocks. We identify the problem of the previous CBL-based pre-placed block floorplan method, and suggest the solution method of this problem. In our method, CBLs consisting of only free blocks are perturbed and maintained during the simulated annealing. Pre-placed blocks are inserted during packing in such a way that the topology of the CBL after insertion of a pre-placed block resembles the topology before insertion. Thus, even with the inclusion of pre-placed blocks, the searching effort via simulated annealing yields acceptable results. Experimental results show that our floorplan method places pre-placed blocks effectively and efficiently.