• 제목/요약/키워드: Solution annealing

검색결과 500건 처리시간 0.029초

Effect of Soft-annealing on the Properties of CIGSe Thin Films Prepared from Solution Precursors

  • Sung, Shi-Joon;Park, Mi Sun;Kim, Dae-Hwan;Kang, Jin-Kyu
    • Bulletin of the Korean Chemical Society
    • /
    • 제34권5호
    • /
    • pp.1473-1476
    • /
    • 2013
  • Solution-based deposition of $CuIn_xGa_{1-x}Se_2$ (CIGSe) thin films is well known non-vacuum process for the fabrication of CIGSe solar cells. However, due to the usage of organic chemicals in the preparation of CIG precursor solutions, the crystallization of the polycrystalline CIGSe and the performance of CIGSe thin film solar cells were significantly affected by the carbon residues from the organic chemicals. In this work, we have tried to eliminate the carbon residues in the CIG precursor thin films efficiently by using soft-annealing process. By adjusting soft-annealing temperature, it is possible to control the amount of carbon residues in CIG precursor thin films. The reduction of the carbon residues in CIG precursors by high temperature soft-annealing improves the grain size and morphology of polycrystalline CIGSe thin films, which are also closely related with the electrical properties of CIGSe thin film solar cells.

회로 분할을 위한 어댑티드 유전자 알고리즘 연구 (A Study of Adapted Genetic Algorithm for Circuit Partitioning)

  • 송호정;김현기
    • 한국콘텐츠학회논문지
    • /
    • 제21권7호
    • /
    • pp.164-170
    • /
    • 2021
  • VLSI 설계에서의 분할(partitioning)은 기능의 최적화를 위하여 설계하고자 하는 회로의 그룹화(grouping)하는 단계로서 레이아웃(layout)에서 면적과 전파지연의 최소화를 위해 함께 배치할 소자를 결정하는 문제이다. 이러한 분할 문제에서 해를 얻기 위해 사용되는 알고리즘은 Kernighan-Lin 알고리즘, Fiduccia Mattheyses heuristic, 시뮬레이티드 어닐링, 유전자 알고리즘 등의 방식이 이용된다. 본 논문에서는 회로 분할 문제에 대하여 유전자 알고리즘과 확률 진화 알고리즘을 결합한 어댑티드 유전자 알고리즘을 이용한 해 공간 탐색(solution space search) 방식을 제안하였으며, 제안한 방식을 유전자 알고리즘 및 시뮬레이티드 어닐링 방식과 비교, 분석하였고, 어댑티드 유전자 알고리즘이 시뮬레이티드 어닐링 및 유전자 알고리즘보다 더 효과적으로 최적해에 근접하는 것을 알 수 있었다.

Flowshop 일정계획을 위한 Simulated Annealing 알고리듬 이용 (A Study on Simulated Annealing Algorithm in Flowshop Scheduling)

  • 우훈식;임동순;김철한
    • 산업경영시스템학회지
    • /
    • 제21권45호
    • /
    • pp.25-32
    • /
    • 1998
  • A modified simulated annealing algorithm is proposed and applied to the permutation flowshop scheduling with the makespan objective. Based on the job deletion and insertion method, a newly defined Max-min perturbation scheme is proposed to obtain a better candidate solution in the simulated annealing process. The simulation experiments are conducted to evaluate the effectiveness of the proposed algorithm against the existing heuristics and results are reported.

  • PDF

Simulated Annealing의 수렴속도 개선에 관한 연구 (Fast Simulated Annealing Algorithm)

  • 정철곤;김중규
    • 한국통신학회논문지
    • /
    • 제27권3A호
    • /
    • pp.284-289
    • /
    • 2002
  • 본 논문에서는 MRF(Markov Random field)를 이용해 영상을 분할할 때, 에너지 최적화를 위해 사용되는 simulated annealing의 수렴속도를 개선하는 방법을 제안하였다. Simulated annealing은 잡음이 포함된 영상이나, 텍스쳐 영상에서 좋은 분할 결과를 나타내지만, 수렴속도가 길다는 단점이 있다. 본 논문에서는 수렴속도를 개선하기 위해 픽셀 레이블의 초기값을 픽셀의 intensity에 따라 adaptive하게 부여하여 simulated annealing을 수행하였다. 이 방법으로 모의실험을 수행한 결과, 기존의 방법보다 수렴 속도를 크게 향상시킬 수 있었다.

정지궤도 위성의 궤도 선정을 위한 알고리즘 (Algorithms for Determining the Geostationary Satellite Orbital Positions)

  • 김수현;김세헌
    • 한국경영과학회지
    • /
    • 제30권1호
    • /
    • pp.177-185
    • /
    • 2005
  • We consider the optimization problem of the geostationary satellite orbital positions. which is very fundamental and important in setting up the new satellite launching plan. We convert the problem into a discrete optimization problem. However, the converted problem is too complex to find an optimal solution. Therefore, we develope the solution procedures using simulated annealing technique. The results of applying our method to some examples are reported.

장기 용수 공급계획 수립을 위한 컴퓨터 모의뜨임 모형 (A Simulated Annealing Model for Long Range Water Supply Planning)

  • 김승권;이준열
    • 한국경영과학회지
    • /
    • 제20권2호
    • /
    • pp.77-93
    • /
    • 1995
  • A mathematical model for long-rage water supply planning was formulated as a dynamic plant location problem with network arc capacity expansion, and illustative example was presented. The proposed solution procedure identifies economical construction timings of surface water supply facilities and water conveyence systems and the best water supply operating patterns as well. In this study, we present a heuristic solution procedure using Simulated annealing Method in conjunction with Bertsekas & Tseng's RELAXT-II for the 0-1 integer network problem.

  • PDF

MAXIMUM TOLERABLE ERROR BOUND IN DISTRIBUTED SIMULATED ANNEALING

  • Hong, Chul-Eui;McMillin, Bruce M.;Ahn, Hee-Il
    • ETRI Journal
    • /
    • 제15권3_4호
    • /
    • pp.1-26
    • /
    • 1994
  • Simulated annealing is an attractive, but expensive, heuristic method for approximating the solution to combinatorial optimization problems. Attempts to parallel simulated annealing, particularly on distributed memory multicomputers, are hampered by the algorithm's requirement of a globally consistent system state. In a multicomputer, maintaining the global state S involves explicit message traffic and is a critical performance bottleneck. To mitigate this bottleneck, it becomes necessary to amortize the overhead of these state updates over as many parallel state changes as possible. By using this technique, errors in the actual cost C(S) of a particular state S will be introduced into the annealing process. This paper places analytically derived bounds on this error in order to assure convergence to the correct optimal result. The resulting parallel simulated annealing algorithm dynamically changes the frequency of global updates as a function of the annealing control parameter, i.e. temperature. Implementation results on an Intel iPSC/2 are reported.

  • PDF

Effect of annealing on the magnetic behavior and microstructures of spherical NiZn ferrite particle prepared by ultrasonic spray pyrolysis

  • Nam, Joong-Hee
    • 한국결정성장학회지
    • /
    • 제17권1호
    • /
    • pp.11-17
    • /
    • 2007
  • The spherical NiZn ferrite particles were prepared by ultrasonic spray pyrolysis with mixed solution of aqueous metal nitrates. The NiZn ferrite particle was observed with nano-sized primary particles of about 10 nm or less before annealing which represented as paramagnetic behavior measured at 77 K and room temperature. The typical abnormal growth of primary particles like polyhedral primary particles was observed by annealing at 1273 K with Zn-concentration dependency. The XRD patterns showed good crystallinity of NiZn ferrite powder after annealing. In annealing process, the intra-particle sintering phenomenon was observed and the spherical particle morphology was collapsed at 1673 K. The saturation magnetization of NiZn ferrite powder for each annealing temperature was decreased with measuring temperature of $77{\sim}$300K.

Influence of Annealing Temperature on Microstructure and Pitting Corrosion Behavior of the 27Cr-7Ni Hyper Duplex Stainless Steel

  • Jeon, Soon-Hyeok;Kim, Hye-Jin;Kong, Kyeong-Ho;Park, Yong-Soo
    • Corrosion Science and Technology
    • /
    • 제13권2호
    • /
    • pp.48-55
    • /
    • 2014
  • Influence of annealing temperature on the microstructure and resistance to pitting corrosion of the hyper duplex stainless steel was investigated in acid and neutral chloride environments. The pitting corrosion resistance is strongly dependent on the microstructure, especially the presence of chromium nitrides ($Cr_2N$), elemental partitioning behavior and volume fraction of ferrite phase and austenite phase. Precipitation of deleterious chromium nitrides reduces the resistance to pitting corrosion due to the formation of Cr-depleted zone. The difference of PREN (Pitting Resistance Equivalent Number) values between the ferrite and austenite phases was the smallest when solution heat-treated at $1060^{\circ}C$. Based on the results of electrochemical tests and critical crevice temperature tests, the optimal annealing temperature is determined as $1060^{\circ}C$.

효율적인 Simulated Annealing 알고리듬을 이용한 이진 위상 컴퓨터형성 홀로그램의 합성 (Synthesis of binary phase computer generated hologram by usngin an efficient simulated annealing algorithm)

  • 김철수;김동호;김정우;배장근;이재곤;김수중
    • 전자공학회논문지A
    • /
    • 제32A권2호
    • /
    • pp.111-119
    • /
    • 1995
  • In this paper, we propose an efficient SA(simulated annealing) algorithm for the synthesis of binary phase computer generated hologram. SA algorithm is a method to find the optimal solution through iterative technique. It is important that selecting cost function and parameters within this algorithm. The aplications of converentional SA algorithm to synthesize parameters within this algorithm. The applications of conventional SA algorithm to synthesize binary hologram have many problems because of inappropriate paramters and cost function. So, we propose a new cost function and a calculation technique of proper parameters required to achieve the optimal solution. Computer simulation results show that the proposed method is better than conventional method in terms of diffraction efficiency and reconstruction error. Also, we show the reconstructed images by the proposed method through optical esperiment.

  • PDF