• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.197-201
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• 2005

When we want to find out the regulatory relationships between genes from gene expression data, dimensionality is one of the big problem. In general, the size of search space in modeling the regulatory relationships grows in O(n$^2$) while the number of genes is increasing. However, hopefully it can be reduced to O(kn) with selected k by applying divide and conquer heuristics which depend on some assumptions about genetic network. In this paper, we approach the modeling problem in divide-and-conquer manner. We applied clustering to make the problem into small sub-problems, then hierarchical model process is applied to those small sub-problems.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.120.3-120
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• 2002

1. Introduction $\textbullet$ Immune system is an evolutionary biological system to protect innumerable foreign materials such as virus, germ cell, and etc. Immune algorithm is the modeling of this system's response that has adaptation and reliableness when disturbance occur. $\textbullet$ In this paper, Immune algorithm is applied to the Steering Controller of AGV in container yard. $\textbullet$ And then the computer simulation result from the viewpoint of yaw rate and lateral displacement is analyzed and compared with result of conventional PID controller. 2. Dynamic Modeling of AGV $\textbullet$ Dynamic modeling has high degree of freedom. But, basic assumptions of this model are that the center of gravity(CG)...

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.387-394
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• 2017

Seismic probabilistic risk assessment (SPRA) requires a large number of simulations to evaluate the seismic vulnerability of structural and nonstructural components in nuclear power plants. The effect of structural modeling and analysis assumptions on dynamic analysis of 3D and simplified 2D stick models of auxiliary buildings and the attached nonstructural components is investigated. Dynamic characteristics and seismic performance of building models are also evaluated, as well as the computational accuracy of the models. The presented results provide a better understanding of the dynamic behavior and seismic performance of auxiliary buildings. The results also help to quantify the impact of uncertainties associated with modeling and analysis of simplified numerical models of structural and nonstructural components subjected to seismic shaking on the predicted seismic failure probabilities of these systems.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.1076-1082
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• 2003

As functional requirement of massive digital information storage devices are on a trend for the higher data transfer rate and lower cost, many different technical efforts are being tested and implemented in the industry. FDB(Fluid Dynamic Soaring) is one of the major breakthroughs in rotor design in terms of TMR budget. Although FDB analysis based on Reynolds' equation is well established and popularly being used for DB design especially for the estimation of bearing stiffness, there are obvious limitations in the approach due to the inherent assumptions. A generalized analysis tool employing the full Navier-Stokes equation and the energy balance is to be beneficial for detailed FDB design In this publication, an efficient geometry modeling method is presented that provides fully integrated inputs for general FVM/FDM codes. By virtue of the flexibility of the presented method, many different detailed FDB design and analysis are carried over with ease.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.191-201
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• 2019

Macroecologists and biogeographers continue to predict the distribution of species across space based on the relationship between biotic processes and environmental variables. This approach uses data related to, for example, species abundance or presence/absence, climate, geomorphology, and soils. Researchers have acknowledged in their statistical analyses the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a degree of dependence between pairs of nearby observations. It has been agreed that residual spatial autocorrelation (rSAC) can have a substantial impact on modeling processes and inferences. However, more attention should be paid to the sources of rSAC and the degree to which rSAC becomes problematic. Here, we review previous studies to identify diverse factors that potentially induce the presence of rSAC in macroecological and biogeographical models. Furthermore, an emphasis is put on the quantification of rSAC by seeking to unveil the magnitude to which the presence of SAC in model residuals becomes detrimental to the modeling process. It turned out that five categories of factors can drive the presence of SAC in model residuals: ecological data and processes, scale and distance, missing variables, sampling design, and assumptions and methodological approaches. Additionally, we noted that more explicit and elaborated discussion of rSAC should be presented in species distribution modeling. Future investigations involving the quantification of rSAC are recommended in order to understand when rSAC can have an adverse effect on the modeling process.

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.1916-1938
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• 2019

The objective of this paper is to discuss the modeling principles of phenomena governing core degradation/melting and in-vessel melt relocation during severe accidents in light water reactors. The proposed modeling approach has been applied in the development of a new accident simulation package, COMPASS (COre Meltdown Progression Accident Simulation Software). COMPASS can be used either as a stand-alone tool to simulate in-vessel meltdown progression up to and including RPV failure, or as a component of an integrated simulation package being developed in Korea for the APR1400 reactor. Interestingly, since the emphasis in the development of COMPASS modeling framework has been on capturing generic mechanistic aspects of accident progression in light water reactors, several parts of the overall model should be useful for future accident studies of other reactor designs, both PWRs and BWRs. The issues discussed in the paper include the overall structure of the model, the rationale behind the formulation of the governing equations and the associated simplifying assumptions, as well as the methodology used to verify both the physical and numerical consistencies of the overall solver. Furthermore, the results of COMPASS validation against two experimental data sets (CORA and PHEBUS) are shown, as well as of the predicted accident progression at TMI-2 reactor.

• Macromolecular Research
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• 제12권2호
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• pp.206-212
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• 2004

To provide guidelines and a basic understanding of static and continuous zone drawing processes, we propose two different mathematical models in terms of the processing conditions and material parameters. Although the models are not finely tuned, because of assumptions made, they are still useful for the analysis of the process and for predicting the processibility.

• 대한산업공학회지
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• 제22권2호
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• pp.277-302
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• 1996

The overall performance of BISDN depends significantly on the interconnection network or the switch fabric. Hence, it is extremely important to evaluate the performance of the network or the fabric. The well developed performance models also provide insight into the factors that determine design tradeoffs as well as quantitative estimates of their importance. The objective of this paper is to investigate and critically compare all the developed performance analysis models of FPS according to internal switch fabric structure, traffic assumptions, performance measures, methodologies, etc. FPSs are described according to their internal fabric structure. Brief history of FPS performance analysis is mentioned and performance analysis modeling is discussed.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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• pp.167-168
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• 2000

A North Pacific Ocean Model has been developed with the Global Ocean Model of the Meteorological Research Institute of Japan which solves the primitive equations with Boussinesq, rigid-lid, and hydrostatic assumptions. The objective of the study is to improve the description of the variability on the East Sea and northwestern Pacific Ocean. (omitted)

• 산업경영시스템학회지
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• 제17권30호
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• pp.167-175
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• 1994

Generally, queueing networks, networks, chains and simulation techniques are among the most widely used evaluation tools to study computer systems, manufacturing systems etc. But, these tools have some assumptions and difficulties. So, this thesis presents a method for manufacturing system using Petri nets. Petri nets are a graphical and mathmatical modeling tool and are promising tool for describing and studying systems that are characterized as being concurrent asychronous, dynamic, distributed and parrallel. It designs Petri net model for processing time of manufacturing system And it applied to a job shop system composed of 8 machines and 4 different job types.