• 제목/요약/키워드: hybrid number

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효율적 DMU 선별을 통한 개선된 기술수준예측 방법: 주력전차 적용을 중심으로 (A Hybrid Technological Forecasting Model by Identifying the Efficient DMUs: An Application to the Main Battle Tank)

  • 김재오;김재희;김승권
    • 기술혁신연구
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    • 제15권2호
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    • pp.83-102
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    • 2007
  • This study extends the existing method of Technology Forecasting with Data Envelopment Analysis (TFDEA) by incorporating a ranking method into the model so that we can reduce the required number of DMUs (Decision Making Units). TFDEA estimates technological rate of change with the set of observations identified by DEA(Data Envelopment Analysis) model. It uses an excessive number of efficient DMUs(Decision Making Units), when the number of inputs and outputs is large compare to the number of observations. Hence, we investigated the possibility of incorporating CCCA(Constrained Canonical Correlation Analysis) into TFDEA so that the ranking of DMUs can be made. Using the ranks developed by CCCA(Constrained Canonical Correlation Analysis), we could limit the number of efficient DMUs that are to be used in the technology forecasting process. The proposed hybrid model could establish technology frontiers with the efficient DMUs for each generation of technology with the help of CCCA that uses the common weights. We applied our hybrid model to forecast the technological progress of main battle tank in order to demonstrate its forecasting capability with practical application. It was found that our hybrid model generated statistically more reliable forecasting results than both TFDEA and the regression model.

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다 단계 혼합흐름공정 일정계획에서 납기지연 작업 수의 최소화를 위한 대체 목적함수 기반 탐색기법 (Surrogate Objective based Search Heuristics to Minimize the Number of Tardy Jobs for Multi-Stage Hybrid Flow Shop Scheduling)

  • 최현선;김형원;이동호
    • 대한산업공학회지
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    • 제35권4호
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    • pp.257-265
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    • 2009
  • This paper considers the hybrid flow shop scheduling problem for the objective of minimizing the number of tardy jobs. In hybrid flow shops, each job is processed through multiple production stages in series, each of which has multiple identical parallel machines. The problem is to determine the allocation of jobs to the parallel machines at each stage as well as the sequence of the jobs assigned to each machine. Due to the complexity of the problem, we suggest search heuristics, tabu search and simulated annealing algorithms with a new method to generate neighborhood solutions. In particular, to evaluate and select neighborhood solutions, three surrogate objectives are additionally suggested because not much difference in the number of tardy jobs can be found among the neighborhoods. To test the performances of the surrogate objective based search heuristics, computational experiments were performed on a number of test instances and the results show that the surrogate objective based search heuristics were better than the original ones. Also, they gave the optimal solutions for most small-size test instances.

조합망 조정에 있어서 승여 관측수의 영향 (The Effects of Redundants in the Hybrid Networks)

  • 양인태;최승필;변무룡
    • 한국측량학회지
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    • 제8권1호
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    • pp.23-30
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    • 1990
  • 본 연구는 조합망 조정에 있어서 승여관측수가 정도에 미치는 영향을 파악하기 위하여 승여관측수를 변화시켜서 망을 조정한 것이다. 또한 수평위치 결정에 있어서 어떤 방법이 가장 효용성이 있는지를 제시하기 위하여 승여관측수에 따른 정밀도를 분석하였다. 본 연구에서 실시한 조합망의 조정에 있어서 평균제곱근 오차는 삼변측량에 비하여 장축에서 약 78∼82%, 단축에서 약 48∼60%, 삼각측량에 비하여 장축에서 약 84∼87%, 단축에서 약 29∼45% 감소되었고, 승여관측수와 정밀도와의 사이에는 Y=464.71429X+13517.57143의 함수관계가 성립한다. 그러나 승여관측수의 증가가 정밀도를 향상시키므로 최적의 승여관측수의 결정은 경제적인 측면에서 매우 중요한 과제이므로 앞으로의 연구과제라 생각된다.

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Nicotiana tabacum과 Petunia inflata의 전기적 원형질체융합에 의한 속간 체세포 잡종의 생성 (Intergeneric Somatic Hybrids by Electrofusion of Protoplasts Between Nicotiana tabacum and Petunia inflata)

  • 김준철
    • Journal of Plant Biology
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    • 제30권1호
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    • pp.1-9
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    • 1987
  • Leaf mesophyll protoplasts of Nicotiana tabacum (nitrate reductase deficient mutant) were fused with cell suspension protoplasts of albino Petunia inflata in an electric field. Hybrid cell colonies were selected for nitrate reductase proficiency and chlorophyll synthesis. Five hybrid plant lines, regenerated from the selected calli lines, were analysed by electrophoresis, number of chromosomes and morphological characters. Somtic hybrid plants showed both parent patterns in the isozymesof isoleucine aminopeptidase and esterase. The hybrids had the expected chromosome number of 62 and exhibited an intermediate floral morphology when compared with the parents, but plant height and leaf arrangement were similar to N. tabacum.

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혼합 흐름공정에서 라인 밸런싱을 위한 휴리스틱 개발 (Heuristics for Line Balancing in Hybrid Flowshops)

  • 이근철
    • 산업경영시스템학회지
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    • 제30권3호
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    • pp.94-102
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    • 2007
  • In this paper, we consider a line balancing problem in hybrid flowshops where each workstation has identical parallel machines. The number of machines in each workstation is determined in ways of satisfying pre-specified throughput rate of the system. To minimize the total number of machines in the systems, we propose five heuristic methods and one simulated annealing method. Extensive computational experiments found the superiorities of two heuristic methods and the meta-heuristic.

Antimicrobial Fiber Products Treated with Silica Hybrid Ag Nanoparticles

  • Kim, Hwa-Jung;Park, Hae-Jin;Choi, Seong-Ho;Park, Hae-Jun
    • 방사선산업학회지
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    • 제6권3호
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    • pp.273-279
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    • 2012
  • Silica hybrid silver nanoparticles showing the strong antimicrobial activity, in which nano-silver is bound to silica molecules, has been synthesized using ${\gamma}-irradiation$ at room temperature. The present study relates to an antimicrobial composition for coating fiber products comprising silica hybrid silver nanoparticles. In this study, we describe antimicrobial fiber products coated with the silica hybrid silver nanoparticles and a method of antimicrobially treating fiber products by coating the fiber products with the silica hybrid silver nanoparticles. The antimicrobial fiber products exhibited excellent antimicrobial effects. In detailed practice, when the present composition comprising nanosized silica-silver was applied to a cloth (fabric) in a concentration of $6.4mg\;yard^{-1}$, the viable cell number decreased to less than 10 cells before and after laundering, resulting in a reduction of 99.9% or greater in the viable cell number. The present composition displays long-lasting potent disinfecting effects on bacteria. Also, we investigated the toxicity of silica hybrid silver nanoparticles in rats. The skin of rats was treated with a 30 ppm nanoparticles solution ($2ml\;Kg^{-1}$) for 8 days. No toxicity was detected in the treatment. These results suggest that the fiber products coated with the silica hybrid silver nanoparticles can be used to inhibit the growth of various microorganisms.

전기 모터설계에의 AutoLISP 응용 (Application of AutoLISP to Electric Motor design)

  • 오철수;공정식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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    • pp.126-129
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    • 1991
  • The effect of each tooth for optimal design of Hybrid permanent magnet step motor is presented on this paper. For this consideration, Hybrid permanent magnet step motor was designed in the first consideration tooth structure on the stator and the rotor and poles structure, as number of teeth on the stator and the rotor and slot depth and pitch of teeth, simulated by AutoLISP. During actual rotating, a chracteristic of Hybrid permanent magnet step motor which designed by AutoLISP program is considered. A chracteristic of Hybrid permanent magnet step motor is considered in change each variable, also. As a result, it was found that characteristic of Hybrid permanent magnet step motor changed in accordance with tooth structure and number of teeth and optimal design is possible by AutoLISP.

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PARALLEL IMPLEMENTATION OF HYBRID ITERATIVE METHODS FOR NONSYMMETRIC LINEAR SYSTEMS

  • Yun, Jae-Heon;Kim, Sang-Wook
    • Journal of applied mathematics & informatics
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    • 제4권1호
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    • pp.1-16
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    • 1997
  • In this paper we study efficient parallel implementation for hybrid iterative methods BICGSTAB and BICGSTAB $(\ell)$ with ${Well}=2$ on the CRAY C90 and the efficiency of their parallel performance is evaluated. numerical experiments suggest that on the CRAY C90 a parallel inner product algorithm called PDOTB be used for the par-allelization of hybrid iterative methods containing sensitive values of inner products. Lastly it is shown that the number of iterations in which parallel hybrid iterative methods satisfy a certain convergence criterion depends on the number of processors to be used.

Numerical Comparisons Between URANS and Hybrid RANS/LES at a High Reynolds Number Flow Using Unstructured Meshes

  • You, Ju-Yeol;Kwon, Oh-Joon
    • International Journal of Aeronautical and Space Sciences
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    • 제11권1호
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    • pp.41-48
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    • 2010
  • In the present study, the turbulent flow fields around a circular cylinder at $Re=3.6{\times}10^6$ were investigated based on an unstructured mesh technique, and the comparisons between URANS(S-A, SST) and hybrid RANS/LES(DES, SAS) methods for the simulation of high Reynolds number flow have been conducted. For this purpose, unsteady characteristics of vortex shedding and time-averaged quantities were compared. A quasi-steady solution-adaptive mesh refinement was also made for the URANS and hybrid RANS/LES approaches. The results showed that the simple changes in the turbulent length scale or source term of turbulent models made the flow fields less dissipative and more realistic in hybrid RANS/LES methods than the URANS approaches.

대규모 Ad-hoc 네트워크 환경에서 트래픽 감소를 위한 선택적 on-demand 라우팅 기법에 관한 연구 (Selective On-demand Zone Routing Protocol for Large Scale Mobile Ad-hoc Networks)

  • 이재호;엄두섭
    • 한국통신학회논문지
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    • 제37권6B호
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    • pp.443-452
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    • 2012
  • Mobile Ad-hoc Networks 환경에서 노드의 이동성을 고려하기 위한 라우팅 알고리즘은 그 특성에 따라 Proactive와 Reactive 방식으로 구분되며, 두 가지 라우팅의 장점을 조합하는 많은 Hybrid 라우팅이 ZRP (Zone Routing Protocol) 알고리즘을 기반으로 설계되어왔다. ZRP는 특정 지역의 Zone을 생성한 후, Zone 내부에는 Proactive, 외부에는 Reactive 방식을 운영하여 근거리 노드들을 향하는 데이터의 경로 탐색 패킷 발생의 비용을 최소화 하였다. 하지만 실제 네트워크에서의 데이터 전송은 짧은 시간 영역에서 특정 노드에게만 요구되는 경향이 있으며, 이에 대한 고려가 없는 ZRP는 이러한 요구를 만족시키기에는 제한적이다. 본 연구는 실시간 데이터 전송량과 전송 경로의 홉 수를 고려하여, 소스 노드와 목적지 노드를 근간으로 하는 Zone을 on-demand로 형성하는 효율적인 Hybrid 라우팅을 제안하고, 이를 위하여 Zone의 생성 및 소멸을 결정하는 DZD (Dynamic Zone Decision) 알고리즘을 고안한다. 또한, 본 연구의 성능을 검증하기 위하여 기존의 Proactive, Reactive, Hybrid 라우팅 알고리즘과의 비교결과를 분석하였다.