• Journal of the Korean Society of Safety
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• v.18 no.3
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• pp.69-74
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• 2003

To investigate the partial discharge and electric field distribution in cable joint parts, we measured the partial discharge and electric field in specimen. The specimens which cross-linked polyethylene(XLPE) and ethylene propylene diene ethylene(EPDM) are used to insulating material for underground cable md cable jointing parts. The polymers are used to insulating material in switchgear which is a kind of transformer equipment and in ultra-high voltage cable. Its using is increasing gradually, the electrical insulation properties are not only excellent but also mechanical property is excellent. And because it is possible to be made void of several type in insulator while it is produced, which the electrical field distribution is changed by void, it has a critical influence to insulator performance. The underground cable is connecting by the jointing material, insulating breakdown and the electric ageing which are caused by several mixing impurity and the damage of cable insulator layer, which reduced the life of cable while intermediate joint kit is connected. Therefore, the computer simulation is used to estimating insulator performance, XLPE is used to the insulating material of ultra-high voltage cable and EPDM is used to insulator layer in joint material kit, and which are produced as specimen. And it is analyzed the electric field concentrating distribution and partial discharge by modeling of computer simulation in void and cable joint kit.

• Journal of the Korea Society for Simulation
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• v.23 no.4
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• pp.171-180
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• 2014

Our Automatic Replanning enables simulation entities to execute goal oriented behavior planning by dynamic behavior linking. Existing methods especially in Semi-Automated Forces (SAF) are mainly executing strict plans which are given at initial stage, thus they are not effective to cope with contingencies especially in a human in the loop simulation where humans interrupt. Moreover, those usually suffer from explosion of behavior combination in attempt to describe all possible countermeasures, and such combinations may be prone to being inconsistent to the situations. Our method generates behavior sequence in which behavior are linked from the goal in the manner of back-propagation. Each behavior has tags of pre/post-conditions. The tags are linked dynamically according to a certain contingency. The method is being applied to a national defense research project to show feasibility.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.20-37
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• 2020

In this paper, we propose a simulation method based on backward simulation and process-oriented simulation to take into account the characteristics of shipbuilding production, which is an order-based industry with a job shop production environment. The shipyard production planning process was investigated to analyze the detailed process, variables and constraints of mid-term production planning. Backward and process-centric simulation methods were applied to the mid-term production planning process and an improved planning process, which considers the shipbuilding characteristics, was proposed. Based on the problem defined by applying backward process-centric simulation, a system which can conduct Discrete Event Simulation (DES) was developed. The developed mid-term planning system can be linked with the existing shipyard Advanced Planning System (APS). Verification of the system was performed with the actual shipyard mid-term production data for the four ships corresponding to a one-year period.

• Journal of Internet Computing and Services
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• v.21 no.6
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• pp.123-132
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• 2020

The EDucation-research Integration through Simulation On the Net (EDISON) platform, which is a web-based platform that provides computational science and engineering simulation execution environments, can offer various analysis environments to students, general users, as well as computational science and engineering researchers. To expand the user base of the simulation environment services, the EDISON platform holds a challenge every year and attempts to increase the competitiveness and excellence of the platform by analyzing the user requirements of the various simulation environment offered. The challenge platform system in the field of computational science and engineering is provided to users in relation to the simulation service used in the existing EDISON platform. Previously, EDISON challenge servicesoperated independently from simulation services, and hence, services such as end-user review and intermediate simulation results could not be linked. To meet these user requirements, the currently in-service challenge platform for computational science and engineering is linked to the existing computational science and engineering service. In addition, it was possible to increase the efficiency of service resources by providing limited services through various analyses of all users participating in the challenge. In this study, by analyzing the simulation and usage environments of users, we provide an improved challenge platform; we also analyze ways to improve the simulation execution environment.

• Structural Engineering and Mechanics
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• v.15 no.5
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• pp.513-534
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• 2003

Using fluid dampers to connect adjacent buildings for enhancing their seismic resistant performance has been recently investigated but limited to linear elastic adjacent buildings only. This paper presents a study of inelastic seismic response of adjacent buildings linked by fluid dampers. A nonlinear finite element planar model using plastic beam element is first constructed to simulate two steel frames connected by fluid dampers. Computed linear elastic seismic responses of the two steel frames with and without fluid dampers under moderate seismic events are then compared with the experimental results obtained from shaking table tests. Finally, elastic-plastic seismic responses of the two steel frames with and without fluid dampers are extensively computed, and the fluid damper performance on controlling inelastic seismic response of the two steel frames is assessed. The effects of the fundamental frequency ratio and structural damping ratio of the two steel frames on the damper performance are also examined. The results show that not only in linear elastic stage but also in inelastic stage, the seismic resistant performance of the two steel frames of different fundamental frequencies can be significantly enhanced if they are properly linked by fluid dampers of appropriate parameters.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.4
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• pp.163-172
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• 2004

Nowadays, to analyze the dynamic characteristics of the automotive driving system, the computer simulation linked up with VR(Virtual Reality) technology is treated as the useful method with the improvement of computing ability. In this paper, the VR simulation system has been developed to investigate the driving characteristics of the ASV(Advanced Safety Vehicle) equipped with an ACC(Adaptive Cruise Control) system. For the purpose, VR environment which generates 3D graphic and sound information of the vehicle, the road, the facilities, and the terrain has been organized for the driving reality. Mathematical models of vehicle dynamic analysis including the ACC model have been constructed for computer simulation. The ACC modulates the throttle and brake functions to regulate the vehicle speed so that vehicles could keep proper spacing. Also, the real-time simulation algorithm synchronizes vehicle dynamic simulation with the graphic rendering. With the developed VR simulation system, simple scenarios are applied to analyze the dynamic characteristics. It is shown that the VR simulation system could be useful to evaluate the adaptive cruise controlled vehicle on various driving conditions.

• Journal of the Korean earth science society
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• v.31 no.5
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• pp.437-447
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• 2010

Spatial estimation of environmental variables has been regarded as an important preliminary procedure for decision-making. A minimum variance criterion, which has often been adopted in traditional kriging algorithms, does not always guarantee the optimal estimates for subsequent decision-making processes. In this paper, a geostatistical framework is illustrated that consists of uncertainty modeling via stochastic simulation and risk modeling based on loss functions for the selection of optimal estimates. Loss functions that quantify the impact of choosing any estimate different from the unknown true value are linked to geostatistical simulation. A hybrid loss function is especially presented to account for the different impact of over- and underestimation of different land-use types. The loss function-specific estimates that minimize the expected loss are chosen as optimal estimates. The applicability of the geostatistical framework is demonstrated and discussed through a case study of copper mapping.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.241-246
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• 2000

Gas hydrates are solid solutions when water molecules are linked through hydrogen bondin create host lattice cavities that can enclose a large variety of guest gas molecules. The natural hydrate crystal may exist at low temperature above the normal freezing point of water and pressure greater than about 30 bars. A lot of quantities of natural gas hydrates exists in the ear many production schemes are being studied. In the present investigation, depressurization method considered to predict the production of gas and the simulation of the two phase flow - gas and - in porous media is being carried out. The simulation show about the fluid flow in porous have a variety of applications in industry. Results provide the appearance of gas and water prod the pressure profile, the saturation of gas/ water/ hydrates profiles and the location of the pl front.

• International Journal of Aeronautical and Space Sciences
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• v.2 no.1
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• pp.28-43
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• 2001

Developed in these two series of paper is a complex dynamic model representing the motion of aircraft on the ground and a computer program for numerical simulation. The first part of paper presents the theoretical derivation of equations of motion of the landing gear system based on the physical principle. Developed model is 'structured' in the sense that the undercarriage system is regarded as an assembly of strut, tire, and wheel, where each component is modeled by a separate module. These modules are linked with two external modules-the aircraft and the runway characteristics-to carry out dynamic analysis and numerical simulation of the aircraft motion on the ground. Three sets of coordinate system associated with strut, wheel/tire and runway are defined, and external loads to each component and response characteristics are examined. Lagrangian formulation is used to derive the undercarriage equations of motion relative to the moving aircraft, and the resultant forces and moments from the undercarriage are transformed to aircraft body axes.

• Journal of the Korea Society for Simulation
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• v.22 no.4
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• pp.11-19
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• 2013

The Korean naval weapon systems, combat experiments establish the concept of Battle operations, and create the future of the new weapons system. Doctrine development and training as well as ranging from experiments for evaluate the performance of mission operations for combat experiments are used. The battle lab is effectively support tool for the Korean Naval battle experiments. The battle lab is through a dedicated testing facility and to build efficient and effective simulation-based acquisition supporting environment. In this paper, the ship / submarines C2 operations virtual simulator was developed to support the concept of Battle operations of naval combat experiments in training and tactical development. The ship C2 operations virtual simulator makes the anti-ship and anti-aircraft the engagement scenario for performed experiments using the SADM. The submarines C2 operations virtual simulator makes the anti-submarine engagement scenario for performed experiments using EAS. EAS System was created before reuse. EAS system by modifying the additional interfaces HLA-RTI has been reused. Reflected in the tactics and training after analysis of the results through the battle experiment. Also increase training fidelity through operator involvement. The anti-ship and anti-aircraft system architecture (SADM) and anti-submarine system architecture (EAS) requires unique design of system framework since two separate architectures should be integrated into a system. An C2 virtual linked architecture was used to integrate different system architecture. A C2 virtual linked software framework, designed that have integrated protocol for battle experimental linkage and battlefield visualization environment.