• Title/Summary/Keyword: Looping Method

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Triangular Mesh Generation on Places or Surfaces by a New Looping Method (새로운 분할법에 의한 평면 및 곡면의 삼각형 요소망 자동생성)

  • 이민철;전만수;임우섭
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.2
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    • pp.79-86
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    • 1999
  • A general approach to automatic generation of triangular meshes on three-dimensional surfaces is presented in this paper. The approach, developed with emphasis on program generality and interface with CAD/CAM systems, is based on the double mapping method and the looping method. The double mapping method is introduced and anew splitting scheme is proposed for the looping method employed for triangular mesh generation on the parametric domain. Several application examples are given.

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The Low Height Looping Technology for Multi-chip Package in Wire Bonder (와이어 본더에서의 초저 루프 기술)

  • Kwak, Byung-Kil;Park, Young-Min;Kook, Sung-June
    • Journal of the Semiconductor & Display Technology
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    • v.6 no.1 s.18
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    • pp.17-22
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    • 2007
  • Recent new packages such as MCP(Multi-Chip Package), QDP(Quadratic Die Package) and DDP(Dual Die Package) have stack type configuration. This kind of multi-layer package is thicker than single layer package. So there is need for the low height looping technology in wirebonder to make these packages thinner. There is stiff zone above ball in wirebonder wire which is called HAZ(Heat Affect Zone). When making low height loop (below $80\;{\mu}m$) with traditional forward loop, stiff wire in HAZ(Heat Affected Zone) above ball is bended and weakened. So the traditional forward looping method cannot be applied to low height loop. SSB(stand-off stitch) wire bonding method was applied to many packages which require very low loops. The drawback of SSB method is making frequent errors at making ball, neck damage above ball on lead and the weakness of ball bonding on lead. The alternative looping method is BNL(ball neckless) looping technology which is already applied to some package(DDP, QDP). The advantage of this method is faster in bonding process and making little errors in wire bonding compared with SSB method. This paper presents the result of BNL looping technology applied in assembly house and several issues related to low loop height consistence and BNL zone weakness.

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A Method For Preventing Data Looping in Multi Tactical Datalink Operation (다중 전술데이터링크 운용에 따른 데이터 루핑 방지 방안)

  • Woo, Soon;Lim, Jae-Sung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.3
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    • pp.314-321
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    • 2013
  • In this paper, we have proposed a method which can prevent data looping in multi tactical data-link operating situation. Because the situation of multi tactical data-link in Korea would be more complex than ever before, data looping is more likely to be happened. To prevent data looping, forwarder has to manage TQ(Track Quality) in forwarded track message by degrading it to enlarge correlation gate. Forwarder also has to discard useless track message which can be determined by minimum TQ value. To decide optimal formula for forwarder to degrade TQ and to determine minimum TQ, a research about track motion, correlation, TQ managing, etc in real system is necessary.

A descriptive study of the impact of the causal looping method to the small group decision-making process of the Korean managers (인과 고리기법이 집단의사결정 과정에 미치는 행태적 연구)

  • 전기정
    • Korean System Dynamics Review
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    • v.3 no.2
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    • pp.69-91
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    • 2002
  • This paper presents an analysis of the impact of the causal looping method to the Korean middle managers' decision-making processes. The sample included the observations of decisions made by 70 groups with 5 to 7 members each. The results showed that the causal looping method was a strong device to help Korean managers followed value-focused decision processes, as opposite to alternative-focuses ones. The lessons from this study suggest a direction for the development of the education method to improve group decision-making processes.

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Development of a General-Purpose Program for Automatic Finite-Element Modelling with Quadrilateral Finite Elements (사각형 유한요소 해석모델의 자동생성 프로그램의 개발)

  • Joun, M.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.1
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    • pp.157-165
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    • 1994
  • A general-purpose program for automatic two-dimensional finite-element modelling with quadrilateral elements was developed in this research. The conventional looping method employed in the program was introduced with emphasis on a new splitting criterion and a splitting scheme developed for improving the method. Some application examples were given, which show versatility and applicability of the developed program.

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A Looping Population Learning Algorithm for the Makespan/Resource Trade-offs Project Scheduling

  • Fang, Ying-Chieh;Chyu, Chiuh-Cheng
    • Industrial Engineering and Management Systems
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    • v.8 no.3
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    • pp.171-180
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    • 2009
  • Population learning algorithm (PLA) is a population-based method that was inspired by the similarities to the phenomenon of social education process in which a diminishing number of individuals enter an increasing number of learning stages. The study aims to develop a framework that repeatedly applying the PLA to solve the discrete resource constrained project scheduling problem with two objectives: minimizing project makespan and renewable resource availability, which are two most common concerns of management when a project is being executed. The PLA looping framework will provide a number of near Pareto optimal schedules for the management to make a choice. Different improvement schemes and learning procedures are applied at different stages of the process. The process gradually becomes more and more sophisticated and time consuming as there are less and less individuals to be taught. An experiment with ProGen generated instances was conducted, and the results demonstrated that the looping framework using PLA outperforms those using genetic local search, particle swarm optimization with local search, scatter search, as well as biased sampling multi-pass algorithm, in terms of several performance measures of proximity. However, the diversity using spread metric does not reveal any significant difference between these five looping algorithms.

Study of Oxygen Carriers with Single Metal Oxides for Chemical-Looping Combustion (Chemical-looping combustion을 위한 단일금속산화물인 산소운반체에 관한 연구)

  • Lee, J.B.;Park, J.S.;Choi, S.I.;Song, Y.W.;Yang, Y.S.;Kim, Y.H.
    • Transactions of the Korean hydrogen and new energy society
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    • v.14 no.3
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    • pp.258-267
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    • 2003
  • A new kind of oxygen carrier material is tested for chemical-looping combustion. NiO, CoO, $Fe_2O_3$ is chosen as metal oxide and YSZ as a binder. Hydrogen fuel is reacted with metal oxide (reduction of metal oxide) and then the reduced metal is successively oxidized by air. Dissolution method is examined to prepare the oxygen carriers. The effects of reaction temperature are measured by a TGA, mechanical strength and regenerability after 10 cycle are examined. $Fe_2O_3/YSZ$ oxygen carrier is bested in mechanical strength and we consider that NiO/YSZ after 3rd cycle are good oxygen carrier in according to reactor design.

Development of an Automatic Two-Dimensional Mesh Generator using an Inward Offset Boundary Technique

  • Choi, Jin-Woo;Kim, Yohng-Jo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.2 no.4
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    • pp.61-66
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    • 2003
  • An excellent mesh construction is of Importance in yielding good results of finite element analysis. The new mesh generation algorithm, which offsets boundaries inward, was developed on the basis of a looping method. An user interface technique and automatic splitting lines which both divide a given domain into subdomains manually or automatically, were used. In addition, the separation method has advantages to prevent the large scale of element size and to control numbers of nodes and elements. This new mesh generation algorithm was proved in practice.

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HiCORE: Hi-C Analysis for Identification of Core Chromatin Looping Regions with Higher Resolution

  • Lee, Hongwoo;Seo, Pil Joon
    • Molecules and Cells
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    • v.44 no.12
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    • pp.883-892
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    • 2021
  • Genome-wide chromosome conformation capture (3C)-based high-throughput sequencing (Hi-C) has enabled identification of genome-wide chromatin loops. Because the Hi-C map with restriction fragment resolution is intrinsically associated with sparsity and stochastic noise, Hi-C data are usually binned at particular intervals; however, the binning method has limited reliability, especially at high resolution. Here, we describe a new method called HiCORE, which provides simple pipelines and algorithms to overcome the limitations of single-layered binning and predict core chromatin regions with three-dimensional physical interactions. In this approach, multiple layers of binning with slightly shifted genome coverage are generated, and interacting bins at each layer are integrated to infer narrower regions of chromatin interactions. HiCORE predicts chromatin looping regions with higher resolution, both in human and Arabidopsis genomes, and contributes to the identification of the precise positions of potential genomic elements in an unbiased manner.

Effect of Pressure on Minimum Fluidization Velocity and Transition Velocity to Fast Fluidization of Oxygen Carrier for Chemical Looping Combustor (케미컬루핑 연소를 위한 산소전달입자의 최소유동화속도 및 고속유동층 전이유속에 미치는 압력의 영향)

  • KIM, JUNGHWAN;BAE, DAL-HEE;BAEK, JEOM-IN;PARK, YEONG-SEONG;RYU, HO-JUNG
    • Transactions of the Korean hydrogen and new energy society
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    • v.28 no.1
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    • pp.85-91
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    • 2017
  • To develop a pressurized chemical looping combustor, effect of pressure on minimum fluidization velocity and transition velocity to fast fluidization was investigated in a two-interconnected pressurized fluidized bed system using oxygen carrier particle. The minimum fluidization velocity was measured by bed pressure drop measurement with variation of gas velocity. The measured minimum fluidization velocity decreased as the pressure increased. The transition velocity to fast fluidization was measured by emptying time method and decreased as the pressure increased. Gas velocity in the fuel reactor should be greater than the minimum fluidization velocity and gas velocity in the air reactor should be greater than the transition velocity to fast fluidization to ensure proper operation of two interconnected fluidized bed system.