• Journal of Environmental Impact Assessment
• /
• v.20 no.4
• /
• pp.435-442
• /
• 2011

In this study, a regression model was developed for prediction of inflow temperature to support an effective thermal stratification simulation of Yongdam Reservoir, using the relationship between gaged inflow temperature and air temperature. The effect of reproductability for thermal stratification was evaluated using EFDC model by gaged vertical profile data of water temperature(from June to December in 2005) and ex-developed regression models. Therefore, in the development process, the coefficient of correlation and determination are 0.96 and 0.922, respectively. Moreover, the developed model showed good performance in reproducing the reservoir thermal stratification. Results of this research can be a role to provide a base for building of prediction model for water quality management in near future.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.2
• /
• pp.435-446
• /
• 1996

In this paper, we present database model of directory systems that perform a task for distributed information repositories in communication network environments. A new model is developed through four phase: (1) A diretory database information is classified that would be stored in directory database as user, administrative, and supplementary information. (2) The modeling criteria are captured that would be used to model information classified. (3) Object-Oriented concepts are used in modeling classified information according to modeling criteria captured. (4) Methods applied to developed model are grouped, and active-based mechanisms such as trigger and constraints are developed. These selected methods and attributes are encapsulated into objects. Consequently they compose an Active Object-Oriented Directory Database Model.

• Korean Journal of Computational Design and Engineering
• /
• v.12 no.5
• /
• pp.321-329
• /
• 2007

The present pipe modeling method requires detailed inputs from a designer to generate a pipe model, and thus it takes much time for the designer to perform such task. Moreover, the pipe model has no relation with the hull structure. Thus, it is time-consuming and requires much effort if design changes arise. In this study, a generating method that generates quickly many pipes using a pipe tray and a conversion method that converts automatically the pipes into objects related with the hull structure are proposed. A pipe modeling system based on the proposed methods is developed. The applicability of the developed system is demonstrated by applying it to the generation of the pipe model of a deadweight 300,000 ton VLCC(Very Large Crude oil Carrier). The results show that the developed system can quickly generate the pipe model in relation with the hull structure.

• Computers and Concrete
• /
• v.7 no.2
• /
• pp.87-102
• /
• 2010

This paper discusses new capabilities developed for the Virtual Penetration Laboratory (VPL) software package to address the challenges of determining Penetration Resistance (PR) equations for concrete materials. Specifically, the paper introduces a three-invariant concrete constitutive model recently developed by the authors. The Advanced Fundamental Concrete (AFC) model was developed to provide a fast-running predictive model to simulate the behavior of concrete and other high-strength geologic materials. The Continuous Evolutionary Algorithms (CEA) automatic fitting algorithms used to fit the new model are discussed, and then examples are presented to demonstrate the effectiveness of the new AFC model. Finally, the AFC model in conjunction with the VPL software package is used to develop a PR equation for a concrete material.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1500-1505
• /
• 2004

This paper presents the design and control of a small Brushless DC (BLDC) Motor for entertainment robots. In order to control the developed BLDC motor, Adaptive Fuzzy Control (AFC) scheme via Parallel distributed Compensation(PDC) is developed for the multi- input/multi-output plant model represented by the Takagi-Sugeno(TS) model. The alternative AFC scheme is proposed to provide asymptotic tracking of a reference signal for the systems with uncertain or slowly time-varying parameters. The developed control law and adaptive law guarantee the boundedness of all signals in the closed-loop system. In addition, the plant state tracks the state of the reference model asymptotically with time for any bounded reference input signal. The suggested design technique is applied to the velocity control of a developed small BLDC motor for entertainment robots.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.04a
• /
• pp.495-499
• /
• 2014

In this study, the finite element modeling for the signal cable and pneumatic hose of the industrial robot is developed. The modulus of elasticity of signal cable and pneumatic hose is predicted by deflection test. Finite element model for the signal cable and pneumatic hose is developed by using the modulus of elasticity obtained from the tests. The developed finite element model is estimated through the vibration analysis. This study shows that the developed finite element model can be effectively utilized in the dynamic analysis.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.6
• /
• pp.248-257
• /
• 1999

A mathematical model was developed to investigate the mechanical interrelation between soil characteristics and main design factors of a tracked vehicles , and predict the tractive performance of the tracked vehicles. Based on the mathematical model, a computer simulation program(TPPMTV98) was developed in this study. The effectiveness of the developed model was verified by comparing the predicted drawbar pulls using TPPMTV98 with measured ones from traction tests with a tracked vehicle reconstructed for test in loam soil with moisture content of 18.92%(d.b). The drawbar pulls measured by the TPPMTV98 were well matched to the measured ones. Such results implied that the model developed in this study could estimate the drawbar pulls well at various soil conditions , and would be very useful as a simulation tool for designing a tracked vehicle and predicting its tractive performance.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2006.04a
• /
• pp.141-148
• /
• 2006

Concrete in a CFT(Concrete Filled Tube) column has enhanced strength and ductility because it is triaxially confined by a steel tube. But CFT columns are designed based on linear analyses by stress block method without the confining effect or the nonlinearity of the concrete. These make the significantly difference between the analysis results and the experimental results. Thus in this study, a nonlinear CFT column model was developed considering the confining effect on the concrete in a CFT column. This developed model was verified by experimental results from other researchers and compared with the results of various specifications. With the developed model, parametric studies were performed and the developed column model showed reasonable and accurate results.

• Journal of the Korea Society for Simulation
• /
• v.9 no.3
• /
• pp.91-102
• /
• 2000

The distribution routing problem is one of the important problems in distribution and supply center management. This research is concerned with an integrated distribution routing problem for multi-supply centers based on improved genetic algorithm and GUI-type programming. In this research, we used a three-step approach; in step 1 a sector clustering model is developed to transfer the multi-supply center problem to single supply center problems which are more easy to be solved, in step 2 we developed a vehicle routing model with time and vehicle capacity constraints and in step 3, we developed a GA-TSP model which can improve the vehicle routing schedules by simulation. For the computational purpose, we developed a GUI-type computer program according to the proposed methods and the sample outputs show that the proposed method is very effective on a set of standard test problems, and it could be potentially useful in solving the distribution routing problems in multi-supply center problem.

• Nuclear Engineering and Technology
• /
• v.40 no.5
• /
• pp.387-396
• /
• 2008

Many experimental analyses for annular film dryouts, which is one of the Critical Heat Flux (CHF) mechanisms, have been performed because of their importance. Numerical approaches must also be developed in order to assess the results from experiments and to perform pre-tests before experiments. Various thermal-hydraulic codes, such as RELAP, COBRATF, MARS, etc., have been used in the assessment of the results of dryout experiments and in experimental pre-tests. These thermal-hydraulic codes are general tools intended for the analysis of various phenomena that could appear in nuclear power plants, and many models applying these codes are unnecessarily complex for the focused analysis of dryout phenomena alone. In this study, a numerical model was developed for annular film dryout using the drift-flux model from uniform heated tube geometry. Several candidates of models that strongly affect dryout, such as the entrainment model, deposition model, and the criterion for the dryout point model, were tested as candidates for inclusion in an optimized annular film dryout model. The optimized model was developed by adopting the best combination of these candidate models, as determined through comparison with experimental data. This optimized model showed reasonable results, which were better than those of MARS code.