• 제목/요약/키워드: computational results

검색결과 9,978건 처리시간 0.044초

단단 축류 터보기계의 유동해석을 위한 계산격자점 생성 프로그램의 개발 및 적용 (Computational Grid Generator for Flow Analysis of Single Stage Axial Turbomachinery with Its Applications)

  • 정희택;박준영;백제현
    • 한국전산유체공학회지
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    • 제5권2호
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    • pp.28-37
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    • 2000
  • An integrated grid generation has been developed for a Navier-Stokes simulation of flow fields inside multistaged turbomachinery The internal grids are generated by the combination of algebraic and elliptic methods. The interactive mode of the present system is coupled efficiently with the design results and flow solvers. Application to several types of axial-flow turbomachines was demonstrated to be reliable and practical as the pre-processor of the computational fluid engineering for gas turbine engines.

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브러시 없는 직류 선형 모터의 추력 계산 방법의 비교 (The Comparison of thrust computational methods of a brushless DC linear motor)

  • 최문석;김용일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.32-34
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    • 1997
  • For a given brushless DC linear motor, we suggest the numerical prediction methods to analyze it's thrust characteristics. First, we calculate the magnetic flux density by the finite element method, and we then compute the maximum thrust with three computational methods - a Lorentz equation, a Maxwell stress method and a virtual work method. To confirm the accuracy of the computational methods, we measure the thrust of the linear motor made by our laboratory with a force-torque sensor. Also, we calculate the thrust by the measured back electromotive force. To choose the appropriate method for a specified application, we compare the maximum thrusts of the computational method and the calculation by the back electromotive force with the measured one. We conclude that the Maxwell stress method is turned out the best because it has the most accurate results among three computational methods and it is more convenient than the calculation method by the back electromotive force.

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천음속 터빈 익렬유동의 수치해석에서의 계산격자점 영향 (EFFECTS OF COMPUTATIONAL GRIDS ON NUMERICAL SIMULATION OF TRANSONIC TURBINE CASCADE FLOWFIELDS)

  • 정희택;정향남
    • 한국전산유체공학회지
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    • 제10권2호
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    • pp.15-20
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    • 2005
  • Numerical investigations have been performed to examine the effects of the computational grids on the prediction of the flow characteristics inside the turbine cascades. Three kinds of grid system based on H-type grid are applied to the high-turning transonic turbine rotor blades and comparisons with the experimental data and the numerical results of each grid structure have been done. In addition, the grid sensitivity on the estimation of the blade performances has been investigated.

Computational Integral Imaging Reconstruction of 3D Object Using a Depth Conversion Technique

  • Shin, Dong-Hak;Kim, Eun-Soo
    • Journal of the Optical Society of Korea
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    • 제12권3호
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    • pp.131-135
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    • 2008
  • Computational integral imaging(CII) has the advantage of generating the volumetric information of the 3D scene without optical devices. However, the reconstruction process of CII requires increasingly larger sizes of reconstructed images and then the computational cost increases as the distance between the lenslet array and the reconstructed output plane increases. In this paper, to overcome this problem, we propose a novel CII method using a depth conversion technique. The proposed method can move a far 3D object near the lenslet array and reduce the computational cost dramatically. To show the usefulness of the proposed method, we carry out the preliminary experiment and its results are presented.

그리드 컴퓨팅 환경을 이용할 전산 유체 해석 (Computational Fluid Dynamics on The Grid Computing Environment)

  • 성춘호;조금원;박형우;이상산;김대희;권장혁
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2002년도 추계 학술대회논문집
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    • pp.71-77
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    • 2002
  • The grid technology is believed to be the next generation research tool for both computational and experimental scientists. With advanced network technologies and middleware, geographically distributed facilities can be tightly connected to provided a huge amount of resources or remote accessibility, In this paper, an overview of grid technology will be introduced with an emphasis in application to computational fluid dynamics. The computational fluid dynamics, which involves solution of partial differential equations, is basically limited by the computing power, With the grid technology, virtually unlimited resources are provided. The schematic structure of middleware and grid environment, as well as some preliminary results are presented.

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계산 에너지 함수 분석을 통한 궤환성을 갖는 단층신경회로망의 성능개선 (Performance improvement of single-layer neural network with feedback by analyzing the computational energy function)

  • 고경희;강민제
    • 전자공학회논문지C
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    • 제34C권12호
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    • pp.54-60
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    • 1997
  • A new method to neglect the third term of the computational energy expression in the single-layer neural network with feedback is introduced. The system often converges to local minima instead of to global minima, because the computational energy is not matched exactly with the cost function being optimized. One of the factors causing these tow functions different is the third term of computational enegy expression. Regarding this third term energy very small, it is always ignored in designing the system. However, a sthe system growing, this third term energy is also growing and this grown term makes the computational energy function much different from the cost function. In results of differency between two functions, system converges to local minima more than before. In this paper, a new method to neglect te third term energy is introduced, so that the system with tis new method has been imroved.

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Computational Challenges for Integrative Genomics

  • Kim, Junhyong;Magwene, Paul
    • Genomics & Informatics
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    • 제2권1호
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    • pp.7-18
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    • 2004
  • Integrated genomics refers to the use of large-scale, systematically collected data from various sources to address biological and biomedical problems. A critical ingredient to a successful research program in integrated genomics is the establishment of an effective computational infrastructure. In this review, we suggest that the computational infrastructure challenges include developing tools for heterogeneous data organization and access, innovating techniques for combining the results of different analyses, and establishing a theoretical framework for integrating biological and quantitative models. For each of the three areas - data integration, analyses integration, and model integration - we review some of the current progress and suggest new topics of research. We argue that the primary computational challenges lie in developing sound theoretical foundations for understanding the genome rather than simply the development of algorithms and programs.

불균등 간격조절과 선형 스펙트럼 쌍 분포특성을 이용한 계산량 단축 알고리즘 (A Reduction Algorithm of Computational Amount using Adjustment the Not Uniform Interval and Distribution Characteristic of LSP)

  • 주상규
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2010년도 춘계학술발표논문집 1부
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    • pp.261-264
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    • 2010
  • Fast algorithm is proposed by using mel scale and the distribution characteristic of LSP parameters, and is to reduce the computational amount. Computational amount means the calculating times of transformation from LPC coefficients to LSP parameters. Among conventional methods, the real root method is considerably simpler than other, but neverthless, it still suffer from its indeterministic computational time. Because the root searching is processed sequentially in frequency region. In this paper, the searching interval is arranged by using mel scale but not it is uniform and searching order is arranged by the distribution characteristic of LSP parameters that is most LSP papameters are occured in specific frequency region. In experimental results, computational amount of the proposed algorithm is reduced about 48.95% in average, but the transformed LSP parameters of the proposed method were the same as those of real root method.

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ANALYSIS OF EQUILIBRIUM METHODS FOR THE COMPUTATIONAL MODEL OF THE MARK-IV ELECTR OREFINER

  • Cumberland, Riley;Hoover, Robert;Phongikaroon, Supathorn;Yim, Man-Sung
    • Nuclear Engineering and Technology
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    • 제43권6호
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    • pp.547-556
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    • 2011
  • Two computational methods for determining equilibrium states for the Mark-IV electrorefiner (ER) have been assessed to improve the current computational electrorefiner model developed at University of Idaho. Both methods were validated against measured data to better understand their effects on the calculation of the equilibrium compositions in the ER. In addition, a sensitivity study was performed on the effect of specific unknown activity coefficients-including sodium in molten cadmium, zirconium in molten cadmium, and sodium chloride in molten LiCl-KCl. Both computational methods produced identical results, which stayed within the 95% confidence interval of the experimental data. Furthermore, sensitivity to unavailable activity coefficients was found to be low (a change in concentration of less than 3 ppm).

라이트봇을 활용한 컴퓨팅 사고력에서 지식 정보의 진단 방안에 관한 연구 (A Study on the Diagnosis Method of Knowledge Information in Computational Thinking using LightBot)

  • 이영석
    • 한국융합학회논문지
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    • 제11권8호
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    • pp.33-38
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    • 2020
  • 현대 사회는 다양한 분야의 문제를 컴퓨터와 접목하여 새로운 방향으로 생각하고 문제를 해결할 필요가 있다. 이렇게 자신만의 아이디어로 컴퓨팅 기술을 활용하여 다양한 문제를 추상화하고 자동화하는 것을 컴퓨팅 사고라고 한다. 본 논문에서는 프로그래밍 교육 상황에서 다양한 문제를 제시하고 이를 해결하기 위해 다양한 문제해결 방식을 찾도록 하는 과정을 통해 컴퓨팅 사고 기반의 지식 정보를 어떻게 진단하고 향상시킬 수 있는지를 분석하고자 한다. 학습자를 진단하기 위해 사전 검사와 라이트봇을 수행하고, 그 결과의 상관관계를 파악하여 학습자의 지식 상태를 체크한 뒤, 문제 해결 학습 기법에 따라 강의를 진행한 평가 결과와 라이트봇 수행 결과의 상관관계를 분석하여, 제안하는 기법에 따라 학습한 학습자들의 집단 평균 성적을 비교 분석한 결과 학습효과가 유의미하게 있는 것으로 나타났다. 본 논문에서 제안하는 문제해결을 위한 컴퓨팅 사고력 기반의 지식 정보를 도출하고 향상시키는 기법을 소프트웨어 교육에 적용한다면 학생들의 흥미와 관심을 유도하여, 학습 효과가 높아질 것이다.