• Title/Summary/Keyword: Deterministic method

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Medoid Determination in Deterministic Annealing-based Pairwise Clustering

  • Lee, Kyung-Mi;Lee, Keon-Myung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.3
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    • pp.178-183
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    • 2011
  • The deterministic annealing-based clustering algorithm is an EM-based algorithm which behaves like simulated annealing method, yet less sensitive to the initialization of parameters. Pairwise clustering is a kind of clustering technique to perform clustering with inter-entity distance information but not enforcing to have detailed attribute information. The pairwise deterministic annealing-based clustering algorithm repeatedly alternates the steps of estimation of mean-fields and the update of membership degrees of data objects to clusters until termination condition holds. Lacking of attribute value information, pairwise clustering algorithms do not explicitly determine the centroids or medoids of clusters in the course of clustering process or at the end of the process. This paper proposes a method to identify the medoids as the centers of formed clusters for the pairwise deterministic annealing-based clustering algorithm. Experimental results show that the proposed method locate meaningful medoids.

Solving Non-deterministic Problem of Ontology Reasoning and Identifying Causes of Inconsistent Ontology using Negated Assumption-based Truth Maintenance System (NATMS를 이용한 온톨로지 추론의 non-deterministic 문제 해결 및 일관성 오류 탐지 기법)

  • Kim, Je-Min;Park, Young-Tack
    • Journal of KIISE:Software and Applications
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    • v.36 no.5
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    • pp.401-410
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    • 2009
  • In order to derive hidden information (concept subsumption, concept satisfiability and realization) of OWL ontology, a number of OWL reasoners have been introduced. The most of these ontology reasoners were implemented using the tableau algorithm. However most reasoners simply report this information without providing a justification for any arbitrary entailment and unsatisfiable concept derived from OWL ontologies. The purpose of this paper is to investigate an optimized method for non-deterministic rule of the tableau algorithm and finding axioms to cause inconsistency in ontology. In this paper, therefore, we propose an optimized method for non-deterministic rule and finding axiom to cause inconsistency using NATMS. In the first place, we introduce Dependency Directed Backtracking to deal non-deterministic rule, a tableau-based decision procedure to find unsatisfiable axiom Furthermore we propose an improved method adapting NATMS.

SIZE OPTIMIATION OF AN ENGINE ROOM MEMBER FOR CRASHWORTHINESS USING RESPONSE SURFACE METHOD

  • Oh, S.;Ye, B.W.;Sin, H.C.
    • International Journal of Automotive Technology
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    • v.8 no.1
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    • pp.93-102
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    • 2007
  • The frontal crash optimization of an engine room member using the response surface method was studied. The engine room member is composed of the front side member and the sub-frame. The thicknesses of the panels on the front side member and the sub-frame were selected as the design variables. The purpose of the optimization was to reduce the weight of the structure, under the constraint that the objective quantity of crash energy is absorbed. The response surface method was used to approximate the crash behavior in mathematical form for optimization procedure. To research the effect of the regression method, two different methodologies were used in constructing the response surface model, the least square method and the moving least square method. The optimum with the two methods was verified by the simulation result. The precision of the surrogate model affected the optimal design. The moving least square method showed better approximation than the least square method. In addition to the deterministic optimization, the reliability-based design optimization using the response surface method was executed to examine the effect of uncertainties in design variables. The requirement for reliability made the optimal structure be heavier than the result of the deterministic optimization. Compared with the deterministic optimum, the optimal design using the reliability-based design optimization showed higher crash energy absorption and little probability of failure in achieving the objective.

A Deterministic Method of Large Prime Number Generation (결정론적인 소수 생성에 관한 연구)

  • Park, Jung-Gil;Park, Bong-Joo;Baek, Ki-Young;Chun, Wang-Sung;Ryou, Jae-Cheol
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.9
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    • pp.2913-2919
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    • 2000
  • It is essential to get large prime numbers in the design of asymmetric encryption algorithm. However, the pseudoprime numbers with high possibility to be primes have been generally used in the asymmetric encryption algorithms, because it is very difficult to find large deterministic prime numbers. In this paper, we propose a new method of deterministic prime number generation. The prime numbers generated by the proposed method have a 100% precise prime characteristic. They are also guaranteed reliability, security strength, and an ability of primitive element generation.

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A Comparative Study of Maintenance Scheduling Methods for Small Utilities

  • Ong, H.L.;Goh, T.N.;Eu, P.S.
    • International Journal of Reliability and Applications
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    • v.4 no.1
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    • pp.13-26
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    • 2003
  • This paper presents a comparative study of a few commonly used maintenance scheduling methods for small utilities that consists solely of thermal generating plants. Two deterministic methods and a stochastic method are examined. The deterministic methods employ the leveling of reserve capacity criterion, of which one uses a heuristic rule to level the deterministic equivalent load obtained by using the product of the unit capacity and its corresponding forced outage rate. The stochastic method simulates the leveling of risk criterion by using the peak load carry capacity of available units. The results indicate that for the size and type of the maintenance scheduling problem described In this study, the stochastic method does not produce a schedule which is significantly better than the deterministic methods.

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NUCLEAR FUEL CYCLE COST ESTIMATION AND SENSITIVITY ANALYSIS OF UNIT COSTS ON THE BASIS OF AN EQUILIBRIUM MODEL

  • KIM, S.K.;KO, W.I.;YOUN, S.R.;GAO, R.X.
    • Nuclear Engineering and Technology
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    • v.47 no.3
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    • pp.306-314
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    • 2015
  • This paper examines the difference in the value of the nuclear fuel cycle cost calculated by the deterministic and probabilistic methods on the basis of an equilibrium model. Calculating using the deterministic method, the direct disposal cost and Pyro-SFR (sodium-cooled fast reactor) nuclear fuel cycle cost, including the reactor cost, were found to be 66.41 mills/kWh and 77.82 mills/kWh, respectively (1 mill = one thousand of a dollar, i.e., $10^{-3}$ $). This is because the cost of SFR is considerably expensive. Calculating again using the probabilistic method, however, the direct disposal cost and Pyro-SFR nuclear fuel cycle cost, excluding the reactor cost, were found be 7.47 mills/kWh and 6.40 mills/kWh, respectively, on the basis of the most likely value. This is because the nuclear fuel cycle cost is significantly affected by the standard deviation and the mean of the unit cost that includes uncertainty. Thus, it is judged that not only the deterministic method, but also the probabilistic method, would also be necessary to evaluate the nuclear fuel cycle cost. By analyzing the sensitivity of the unit cost in each phase of the nuclear fuel cycle, it was found that the uranium unit price is the most influential factor in determining nuclear fuel cycle costs.

New hybrid stochastic-deterministic rock block analysis method in tunnels (터널의 신 하이브리드 추계학적-확정론적 암반블럭 해석기법)

  • Hwang, Jae-Yun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.12 no.3
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    • pp.265-274
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    • 2010
  • In many tunnels, falling or sliding of rock blocks often occur, which cannot be predicted because of the complexity of rock discontinuities and it has brought an exponential increase in costs and time to manage. It is difficult to estimate the properties of rock masses before the tunnel excavation. The observational design and construction method in tunnels has been becoming important recently. In this study, a new hybrid stochastic-deterministic rock block analysis method for the prediction of the unstable rock blocks before the tunnel excavation is proposed, and then applied to the tunnel construction based on actual rock discontinuity information observed in the field. The comparisons and investigations with the analytical results in the tunnel construction have confirmed the validity and applicability of this new hybrid stochastic-deterministic rock block analysis method in tunnels.

Random vibration and deterministic analyses of cable-stayed bridges to asynchronous ground motion

  • Soyluk, K.;Dumanoglu, A.A.;Tuna, M.E.
    • Structural Engineering and Mechanics
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    • v.18 no.2
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    • pp.231-246
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    • 2004
  • In this paper, a comparison of various random vibration and deterministic dynamic analyses of cable-stayed bridges subjected to asynchronous ground motion is presented. Different random vibration methods are included to determine the dynamic behaviour of a cable-stayed bridge for various ground motion wave velocities. As a numerical example the Jindo Bridge located in South Korea is chosen and a 413 DOF mathematical model is employed for this bridge. The results obtained from a spectral analysis approach are compared with those of two random vibration based response spectrum methods and a deterministic method. The analyses suggest that the structural responses usually show important amplifications depending on the decreasing ground motion wave velocities.

A Study on the Preliminary Ship Design Method using Deterministic Approach and Probabilistic Approach (확정론적 기법 및 확률론적 기법을 적용한 선박 초기 설계 방법에 관한 연구)

  • 양영순;박창규;유원선
    • Journal of the Society of Naval Architects of Korea
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    • v.41 no.3
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    • pp.49-59
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    • 2004
  • The paper describes the preliminary ship design method using deterministic approach and probabilistic approach. In deterministic approach, there are computational aspects to applying not only the integration concurrently of principal dimension decisions and hull form variations but also hydrostatic coefficients that applied to optimization iterative process. Therefore, this paper developed that actual design concept at the preliminary ship design more than sequential design which separated in principal dimension decisions and hull form variations. Furthermore, a probabilistic approach at the preliminary ship design is applied to efficiently solve design information uncertainty that compared to deterministic approach.

Reliability-Based Design of Vertical Drain Method Considering Uncertainties in Geotechnical Property (연약지반의 불확실성을 고려한 연직배수공법의 신뢰성 설계)

  • Kim, Byung-Il;Sah, Sang-Ho;Kim, Bang-Sig;Kim, Soo-Sam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.1148-1154
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    • 2006
  • Composite discharge capacity tests and smear effect tests are carried out to estimate the parameters for the reliability-based design of vertical drain method. Also the probabilistic and deterministic solutions of radial consolidation theory are presented. It compared to the result of reliability-based design and that of deterministic design using the tested and estimated parameters. The results indicated that the drain spacing is larger the deterministic method than the probabilistic method because the former is not considered the uncertainties in the properties of soil. The divergence of methods is dependent on the probability of achieving target degree of consolidation by a given time and the coefficient of variation(COV) of the coefficient of horizontal consolidation$(c_h)$.

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