• Title/Summary/Keyword: Simulated Study

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

  • Jeong, Jeong-Hwan;Ahn, Seok-Hwan;Park, In-Duck;Nam, Ki-Woo
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.10a
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    • pp.127-132
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    • 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.

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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
    • Proceedings of the KACD Conference
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    • 2003.11a
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    • pp.554-554
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    • 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)

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

  • Chen Ming-Kuen
    • Proceedings of the Korean Society for Quality Management Conference
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    • 1998.11a
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    • pp.696-704
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    • 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.

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

  • Choi, Myoung Sub;Kim, Sunhee;Park, Chan Ryul;Kim, Namyoung;Shin, Jinsub
    • Journal of Korean Society of Forest Science
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    • v.97 no.4
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    • pp.357-362
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    • 2008
  • We compared the morphological characters and stable isotopes of seeds of wild simulated ginseng with those of cultivated field ginseng. Seeds were collected from ten areas for wild simulated ginseng and two areas for cultivated field ginseng. The length, width, thickness and number of seeds per gram were measured and the ratio of stable isotopes of carbon and nitrogen was analysed as well. There was a overlapping variation of morphological characters and the ratio of stable isotope of the wild simulated ginseng among study areas. In Geumsan area, compared with the seed of cultivated field ginseng, the seed of wild simulated ginseng was significantly small and light, and the ${\delta}^{15}N$(‰) of wild simulated ginseng was lower than that of cultivated field ginseng. However, it is somewhat impossible to compare the regional variation of the unique value of ${\delta}^{15}N$(‰) among study areas of wild simulated ginseng. We can suggest the value of ${\delta}^{15}N$(‰) can be used as detection factor for cultivation regime like chemical fertilization and organic farming.

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
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    • v.7 no.3
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    • pp.148-151
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    • 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.

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

  • Park, So-Yun;Seo, Hyun-Ah
    • The Journal of the Korea Contents Association
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    • v.21 no.4
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    • pp.370-381
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    • 2021
  • This study examines the perceptions and demands of pre-service early childhood teachers about the Demonstration of simulated instruction for 350 students in early childhood education at 3-4 years university located in Busan, Ulsan, and Gimhae. And through this, the purposes of study are to provide basic data based on the current level of pre-school teachers for instructors leading simulated instruction and to seek effective management plans for simulated instruction to improve teaching ability. As a result of the study, pre-service early childhood teachers recognized that simulated instructions were necessary in teacher training course and helped to improve teaching ability, but they did not actively agree to expand simulated instructions and were not very satisfied with the methods of instructors in demonstration of simulated instruction. They wanted to receive feedback from instructors who have practical teaching knowledge and skills based on field experience at least two times during preparation stage and evaluation stage of the simulated instructions. And they wanted to be guided specifically on principles and methods of preparing educational plans, effective interactions and questions with young children. They wanted the feedback, the most preferred form of feedback is form of participations by all class members and instructors. In addition to instructor's feedback, they required experience of simulated instruction in which infants and toddlers participate together.

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

  • Lee, Sang-Heon
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2005.05a
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    • pp.1020-1025
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    • 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.

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

  • Lee, Young-Jin;Lee, Kwon-Soon
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.288-289
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    • 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.

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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
    • Proceedings of the KACD Conference
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    • 2003.11a
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    • pp.595-595
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    • 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)

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

  • Kim Jinhwa
    • Journal of the Korean Operations Research and Management Science Society
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    • v.29 no.4
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    • pp.117-134
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    • 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.