• 제목/요약/키워드: Simulated Study

검색결과 7,454건 처리시간 0.042초

열재현에 의한 SS300 및 STS304의 기계적 성질 및 초음파 특성 (Mechanical Properties and Ultrasonic Characteristic of SS400 and STS304 by Simulated Heats)

  • 정정환;안석환;박인덕;남기우
    • 한국해양공학회:학술대회논문집
    • /
    • 한국해양공학회 2003년도 추계학술대회 논문집
    • /
    • pp.127-132
    • /
    • 2003
  • In a today industry, the welding is doing a many portion in structure manufacture. This study is simulated heat of heat-effected zone and researched a mechanical properties and ultrasonic characteristic in used the SS400 and the STS304. As the result mechanical properties of steel that become drawing decreased because of remaining stress by strain gardening according as simulated heat temperature rises, but according as temperature rises in material that do simulated heat after have done annealing, mechanical propensity was improved. The velocity and attenuation become different by effect of remaining stress than effect of material internal microstructure in ultrasonic wave test. In the case of STS304, there was change in mechanical properties by effect that is by strain hardening, but there was no change in material that simulated heat after annealing. When become drawing in ultrasonic waves test, according as simulated heat temperatures rise, change of attenuation coefficient is looked, but material that simulated heat after annealing was no change almost both the volocity and attenuation.

  • PDF

A comparative study on the shaping ability of ProFile and Pro Taper, K-Flexofile in simulated canals with different angles of curvature

  • Lee, Bo-Kum;Hwang, In-Nam;Oh, Won-Mann
    • 대한치과보존학회:학술대회논문집
    • /
    • 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
    • /
    • pp.554-554
    • /
    • 2003
  • I. Objectives This study was done to evaluate the shaping ability of ProFile and ProTaper, K-Flexofile during instrumentation in simulated resin canals with different angles of curvature. II. Materials and Methods Ninety simulated root canals with a curvature of 15, 30 and 45 degree (following Schneider's method) were made of epoxy resin ($EPOXICURE^{TM}$, BUEHLER, USA) for this study. The canal length of simulated root canals was adjusted to 18 mm. The beginning point of curvature was positioned at 10mm from the canal orifice.(omitted)

  • PDF

The Comparison of Neural Network Learning Paradigms: Backpropagation, Simulated Annealing, Genetic Algorithm, and Tabu Search

  • Chen Ming-Kuen
    • 한국품질경영학회:학술대회논문집
    • /
    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
    • /
    • pp.696-704
    • /
    • 1998
  • Artificial neural networks (ANN) have successfully applied into various areas. But, How to effectively established network is the one of the critical problem. This study will focus on this problem and try to extensively study. Firstly, four different learning algorithms ANNs were constructed. The learning algorithms include backpropagation, simulated annealing, genetic algorithm, and tabu search. The experimental results of the above four different learning algorithms were tested by statistical analysis. The training RMS, training time, and testing RMS were used as the comparison criteria.

  • PDF

국내 산양삼과 인삼 종자의 형태적 형질과 안정성 동위원소 비교 (Comparison of Morphological Characters and Stable Isotopes of Seeds between Wild Simulated Ginseng and Cultivated Field Ginseng)

  • 최명섭;김선희;박찬열;김남영;신진섭
    • 한국산림과학회지
    • /
    • 제97권4호
    • /
    • pp.357-362
    • /
    • 2008
  • 국내 산양삼과 인삼 종자의 형태적 형질과 안정성 동위원소를 비교하였다. 산양삼 10개 산지와 인삼 2개 산지에서 종자를 채집하여 종자의 길이, 폭, 두께, 그램당 립수를 측정하였으며, 탄소, 질소 안정성 동위원소비를 분석하였다. 산양삼 종자의 형태적 형질과 안정성 동위원소비는 지역간에 중복되는 변이를 나타냈다. 금산지역의 산양삼과 인삼을 비교한 결과, 산양삼 종자는 인삼과 비교하여 유의하게 크기가 작고 무게가 가벼웠으며, 질소 동위원소비는 산양삼 종자에서 낮았다. 유사한 지역 환경에서 산양삼과 인삼 종자는 형태적으로 구분할 수 있었고, 산양삼 종자의 질소 동위원소비는 경작 유형을 반영하였으나, 지역간 절대적 비교는 할 수 없었다.

The Effect of Increasing Control-to-case Ratio on Statistical Power in a Simulated Case-control SNP Association Study

  • Kang, Moon-Su;Choi, Sun-Hee;Koh, In-Song
    • Genomics & Informatics
    • /
    • 제7권3호
    • /
    • pp.148-151
    • /
    • 2009
  • Generally, larger sample size leads to a greater statistical power to detect a significant difference. We may increase the sample size for both case and control in order to obtain greater power. However, it is often the case that increasing sample size for case is not feasible for a variety of reasons. In order to look at change in power as the ratio of control to case varies (1:1 to 4:1), we conduct association tests with simulated data generated by PLINK. The simulated data consist of 50 disease SNPs and 300 non-disease SNPs and we compute powers for disease SNPs. Genetic Power Calculator was used for computing powers with varying the ratio of control to case (1:1, 2:1, 3:1, 4:1). In this study, we show that gains in statistical power resulting from increasing the ratio of control to case are substantial for the simulated data. Similar results might be expected for real data.

예비유아교사의 모의수업 인식 및 요구도 분석 (An Analysis of Pre-service Early Childhood Education Teachers' Perceptions and Demands through Demonstration of Simulated Instruction)

  • 박소윤;서현아
    • 한국콘텐츠학회논문지
    • /
    • 제21권4호
    • /
    • pp.370-381
    • /
    • 2021
  • 본 연구는 부산, 울산, 김해 지역에 소재한 3-4년제 대학 유아교육과 재학생 350명을 대상으로 예비유아교사들의 모의수업에 대한 인식과 요구도를 살펴보고자 하였다. 이를 통해 교원양성기관에서 모의수업을 지도하는 교수자들에게 예비유아교사의 현재 수준에 근거한 기초자료를 제공하고 모의수업의 효과적인 운영방안을 모색하고자 하는데 목적이 있다. 연구 결과 예비유아교사는 모의수업은 교원양성교육에서 필요하며 수업능력 향상에 도움을 준다고 인식하고 있었지만 모의수업 횟수를 늘리는 것에는 찬성하지 않고 있었으며 교수자의 모의수업 지도 방법에 대해서도 매우 만족하고 있지는 않은 것으로 나타났다. 또한 현장경력을 바탕으로 한 실제적 수업지식과 기술이 있는 교수자에게 모의수업 준비단계와 평가단계의 최소 2회의 피드백을 받길 원하고 있었으며 구체적으로 교육계획안 작성 원리 및 방법과 유아와 효과적 상호작용 및 발문에 대해 지도받고자 하였다. 피드백은 학급 구성원 모두와 교수자가 함께 참여하는 형태를 가장 선호하였으며 교수자 피드백 이외에는 영유아가 함께 참여하는 모의수업 경험을 요구하였다.

탄도미사일 방어무기체계 배치모형 연구 (Optimal Allocation Model for Ballistic Missile Defense System by Simulated Annealing Algorithm)

  • 이상헌
    • 한국경영과학회:학술대회논문집
    • /
    • 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
    • /
    • pp.1020-1025
    • /
    • 2005
  • The set covering(SC) problem has many practical application of modeling not only real world problems in civilian but also in military. In this paper we study optimal allocation model for maximizing utility of consolidating old fashioned and new air defense weapon system like Patriot missile and develop the new computational algorithm for the SC problem by using simulated annealing(SA) algorithm. This study examines three different methods: 1) simulated annealing(SA); 2) accelerated simulated annealing(ASA); and 3) selection by effectiveness degree(SED) with SA. The SED is adopted as an enhanced SA algorithm that the neighboring solutions could be generated only in possible optimal feasible region at the PERTURB function. Furthermore, we perform various experiments for both a reduced and an extended scale sized situations depending on the number of customers(protective objective), service(air defense), facilities(air defense artillery), threat, candidate locations, and azimuth angles of Patriot missile. Our experiment shows that the SED obtains the best results than others.

  • PDF

Simulated Annealing법의 적용시 Starting Temperature 결정에 관한 연구 (A Study on Determination of Starting Temperature for the Method of Simulated Annealing)

  • 이영진;이권순
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1992년도 하계학술대회 논문집 A
    • /
    • pp.288-289
    • /
    • 1992
  • The method of simulated annealing is a technique that has recently attracted significant attention as suitable for optimization problem of very large scale. If the temperature is too high, then some of the structure created by the heuristic will be destroyed and unnecessary extra work will be done. If it is too low then solution is lost, similar to the case of a quenching cooling schedule in the Simulated Annealing (SA) phase. Therefore, a crucial issue in this study is the determination of the starting temperature and cooling schedule for SA phase.

  • PDF

A comparative study of several nickel-titanium instruments on canal shaping ability in the simulated canal with abrupt curvature

  • Lim, Jung-Jang;Hwang, In-Nam;Oh, Won-Mann
    • 대한치과보존학회:학술대회논문집
    • /
    • 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
    • /
    • pp.595-595
    • /
    • 2003
  • I. Objectives This study was done to evaluate which type of Ni-Ti instrument be able to perform canal shape well in the simulated canal with abrupt curvature near it's apex. II. Materials and Methods A total of 96 simulated root canals were made in epoxy resin(EPOXICURETM, BUEHLER, USA), #15 finger spreader (MANI, Japan) were used as root canal templates. The simulated root canal were made with radius of curvature of 1.5 mm, 3.0 mm, 4.0 mm, 6.0 mm respectively, and angle of curvature of all simulate camals was 90 degree.(omitted)

  • PDF

인간의 학습과정 시뮬레이션에 의한 경험적 데이터를 이용한 최적화 방법 (An Empirical Data Driven Optimization Approach By Simulating Human Learning Processes)

  • 김진화
    • 한국경영과학회지
    • /
    • 제29권4호
    • /
    • pp.117-134
    • /
    • 2004
  • This study suggests a data driven optimization approach, which simulates the models of human learning processes from cognitive sciences. It shows how the human learning processes can be simulated and applied to solving combinatorial optimization problems. The main advantage of using this method is in applying it into problems, which are very difficult to simulate. 'Undecidable' problems are considered as best possible application areas for this suggested approach. The concept of an 'undecidable' problem is redefined. The learning models in human learning and decision-making related to combinatorial optimization in cognitive and neural sciences are designed, simulated, and implemented to solve an optimization problem. We call this approach 'SLO : simulated learning for optimization.' Two different versions of SLO have been designed: SLO with position & link matrix, and SLO with decomposition algorithm. The methods are tested for traveling salespersons problems to show how these approaches derive new solution empirically. The tests show that simulated learning for optimization produces new solutions with better performance empirically. Its performance, compared to other hill-climbing type methods, is relatively good.