• 제목/요약/키워드: standard model

검색결과 6,956건 처리시간 0.029초

재순환 영역이 있는 축대칭 난류 확산화염의 구조 (II) (The Structure of Axisymmeric Turbulent Diffusion Flame(II))

  • 이병무;신현동
    • 대한기계학회논문집
    • /
    • 제10권1호
    • /
    • pp.70-77
    • /
    • 1986
  • 본 논문에서는 재순환 영역이 존재하는 축대칭 난류 확산화염 구조예측의 전 단계로서, 이미 발표된 바있는 필자의 실험 데이터를 바탕으로 하여 등온유동에 서의 난류모델을 검토한다. 유선의 곡률이 큰 유동에 2방정식 모델을 적용함은 큰 결점을 보완한 수정-2방정식모델을 채택하여 실험결과와 비교, 검토하여 모델의 타당성을 조사하였다.

An Improved Efficient Provable Secure Identity-Based Identification Scheme in the Standard Model

  • Tan, Syh-Yuan;Chin, Ji-Jian;Heng, Swee-Huay;Goi, Bok-Min
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제7권4호
    • /
    • pp.910-922
    • /
    • 2013
  • In 2008, Chin et al. proposed an efficient and provable secure identity-based identification scheme in the standard model. However, we discovered a subtle flaw in the security proof which renders the proof of security useless. While no weakness has been found in the scheme itself, a scheme that is desired would be one with an accompanying proof of security. In this paper, we provide a fix to the scheme to overcome the problem without affecting the efficiency as well as a new proof of security. In particular, we show that only one extra pre-computable pairing operation should be added into the commitment phase of the identification protocol to fix the proof of security under the same hard problems.

표준원가회계방식을 적용한 워크플로우 인스턴스의 비용 평가 모형 (A Cost Evaluation Model for Workflow Instances based on Standard Cost Accounting)

  • 이재훈;장중순
    • 한국경영과학회:학술대회논문집
    • /
    • 한국경영과학회 2008년도 추계학술대회 및 정기총회
    • /
    • pp.460-463
    • /
    • 2008
  • This study tries to apply standard cost accounting model to evaluate the cost of workflow instances. Previous studies mainly focus on matching workflow activities into the elements of Activity based costing in order to assign cost drivers, but rarely examine how to evaluate their instance cost. In this study, we estimate unrealized standard cost from workflow model, and realized cost from accomplished instances. On running, workflow engine cumulates cost of finished activities and it enables to monitor the difference between the target cost and the actual cost dynamically at each step of workflow processes. We implemented a prototype which shows that the proposed work can evaluate effectively the cost of various workflow patterns.

  • PDF

Computational Science-based Research on Dark Matter at KISTI

  • Cho, Kihyeon
    • Journal of Astronomy and Space Sciences
    • /
    • 제34권2호
    • /
    • pp.153-159
    • /
    • 2017
  • The Standard Model of particle physics was established after discovery of the Higgs boson. However, little is known about dark matter, which has mass and constitutes approximately five times the number of standard model particles in space. The cross-section of dark matter is much smaller than that of the existing Standard Model, and the range of the predicted mass is wide, from a few eV to several PeV. Therefore, massive amounts of astronomical, accelerator, and simulation data are required to study dark matter, and efficient processing of these data is vital. Computational science, which can combine experiments, theory, and simulation, is thus necessary for dark matter research. A computational science and deep learning-based dark matter research platform is suggested for enhanced coverage and sharing of data. Such an approach can efficiently add to our existing knowledge on the mystery of dark matter.

시뮬레이션 출력비 추정량의 통계적 분석 (Statistical Analysis of Simulation Output Ratios)

  • 홍윤기
    • 한국시뮬레이션학회논문지
    • /
    • 제3권1호
    • /
    • pp.17-28
    • /
    • 1994
  • A statistical procedure is developed to estimate the relative difference between two parameters each obtained from either true model or approximate model. Double sample procedure is applied to find the additional number of simulation runs satisfying the preassigned absolute precision of the confidence interval. Two types of parameters, mean and standard deviation, are considered as the performance measures and tried to show the validity of the model by examining both queues and inventory systems. In each system it is assumed that there are three distinct means and their own standard deviations and they form the simultaneous confidence intervals but with control in the sense that the absolute precision for each confidence interval is bounded on the limits with preassigned confidence level. The results of this study may contribute to some situations, for instance, first, we need a statistical method to compare the effectiveness between two alternatives, second, we find the adquate number of replications with any level of absolute precision to avoid the unrealistic cost of running simulation models, third, we are interested in analyzing the standard deviation of the output measure, ..., etc.

  • PDF

고속 철도 차량용 판토그래프와 가선계의 접촉력 예측을 위한 수치 해석 모델 개발 (Development of Numerical Analysis Model to Estimate the Contact Force between the Pantograph and Catenary of a High-speed Train)

  • 정성필;박태원;김영국;백진성
    • 한국소음진동공학회논문집
    • /
    • 제21권5호
    • /
    • pp.461-467
    • /
    • 2011
  • This study aims to create a numerical analysis model which can investigate the dynamic interaction between pantograph and overhead contact wire used for a high-speed railway vehicle, and validate the simulation results according to EN 50318 standard. Finite element analysis models of pantograph and overhead contact line are created using SAMCEF, a commercial FE analysis program. The mean, standard deviation, maximum and minimum values of contact forces are obtained. The simulation results are validated according to EN 50318, and the possibility of simulating the collecting characteristic of an actual pantograph system by using the developed model is discussed.

자동차용 판넬의 프레스금형 제작에서의 요소기술의 평가에 관한 연구 (A study on the Assessment of Component Technology in Press-Die Making of Car Panel)

    • 한국생산제조학회지
    • /
    • 제7권3호
    • /
    • pp.85-91
    • /
    • 1998
  • In this paper an assessment has been proceeded about component technology that stamping car panel can be designed and manufactured efficiently. Also this study investigate standard model of CAD/CAM system in production process of automobile dies, Recently, motor companies are doing their best to increase productivity and to reduce production time. So to develop user-friendly and effective standard model of CAD/CAM system is very important. The cbtained results will lead to the reductions in lead time and man-hour required for the design and manufacture of the automobile dies.

  • PDF

TURING INSTABILITY IN A PREDATOR-PREY MODEL IN PATCHY SPACE WITH SELF AND CROSS DIFFUSION

  • Aly, Shaban
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • 제17권2호
    • /
    • pp.129-138
    • /
    • 2013
  • A spatio-temporal models as systems of ODE which describe two-species Beddington - DeAngelis type predator-prey system living in a habitat of two identical patches linked by migration is investigated. It is assumed in the model that the per capita migration rate of each species is influenced not only by its own but also by the other one's density, i.e. there is cross diffusion present. We show that a standard (self-diffusion) system may be either stable or unstable, a cross-diffusion response can stabilize an unstable standard system and destabilize a stable standard system. For the diffusively stable model, numerical studies show that at a critical value of the bifurcation parameter the system undergoes a Turing bifurcation and the cross migration response is an important factor that should not be ignored when pattern emerges.

데이터베이스 기술 분류 표준화 연구 (A Study on the Standardization for the Classification of Database Technologies)

  • 최명규
    • 정보관리연구
    • /
    • 제27권2호
    • /
    • pp.33-64
    • /
    • 1996
  • 본 연구는 데이터베이스 기술분류의 표준시안을 제시하기 위하여 1차년도(1994년) 연구 결과에 대한 관점을 체계화하고 구체화시켜 수정, 보완하는 형식으로 이루어졌다. 분류관점을 정보와 이를 지원하는 시스템 측면으로 크게 나누어, 데이터베이스 일반, 정보유통, 정보검색, 데이터베이스 시스템, 주변 관련주제를 분류기준으로 하는 표준 시안의 모형이 제시되었다.

  • PDF

표준 모델의 2자유도 위너-호프 제어기 설계 (Wiener-Hopf Design of the Two-Degree-of-Freedom Controller for the Standard Model)

  • 조용석;최군호;박기헌
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제49권3호
    • /
    • pp.102-110
    • /
    • 2000
  • In this paper, Wiener-Hopf design of the two-degree-of-freedom(2DOF) controller configuration is treated for the standard plant model. It is shown that the 2DOF structure makes it possible to treat the design of feedback properties and reference tracking problem separately. Wiener-Hopf factorization technique is used to obtain the optimal controller which minimizes a given quadratic cost index. The class of all stabilizing controllers that yield finite cost index is also characterized. An illustrative example is given for the step reference tracking problem which can not be treated by the conventional H2 controller formula.

  • PDF