• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1729-1738
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• 2014

The offline verification of state of charge estimation, power estimation, fault diagnosis and emergency control of battery management system (BMS) is one of the key technologies in the field of electric vehicle battery system. It is difficult to test and verify the battery management system software in the early stage, especially for algorithms such as system state estimation, emergency control and so on. This article carried out the virtual environment modeling for verification of battery management system. According to the input/output parameters of battery management system, virtual environment is determined to run the battery management system. With the integration of the developed BMS model and the external model, the virtual environment model has been established for battery management system in the vehicle's working environment. Through the virtual environment model, the effectiveness of software algorithm of BMS was verified, such as battery state parameters estimation, power estimation, fault diagnosis, charge and discharge management, etc.

• Journal of Internet Computing and Services
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• v.23 no.1
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• pp.49-68
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• 2022

The operation system of a shipping company is still maintaining the mainframe based terminal access environment or the client/server based environment. Nowadays shipping companies that try to migrate it into a web-based environment are increasing. However, in the transition, if the design is processed by the old configuration and knowledge without considering the characteristics of the web-based environment and shipping business, various security vulnerabilities will be revealed at the actual system operation stage, and system maintenance costs to fix them will increase significantly. Therefore, in the transition to a web-based environment, a security design must be carried out from the design stage to ensure system safety and to reduce security-related maintenance costs in the future. This paper examines the characteristics of various threat modeling techniques, selects suitable modeling technique for the operation system of a shipping company, applies data flow diagram and STRIDE threat modeling technique to shipping business, derives possible security threats from each component of the data flow diagram in the attacker's point of view, validates the derived threats by mapping them with attack library items, represents the attack tree having various attack scenarios that attackers can attempt to achieve their final goals, organizes into the checklist that has security check items, associated threats and security requirements, and finally presents 23 security requirements that can respond to threats. Unlike the existing general security requirements, the security requirements presented in this paper reflect the characteristics of shipping business because they are derived by analyzing the actual business of a shipping company and applying threat modeling technique. Therefore, I think that the presented security requirements will be of great help in the security design of shipping companies that are trying to proceed with the transition to a web-based environment in the future.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1093-1097
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• 2004

We propose 'the haptic primitive' for haptic rendering without the need to solve complicated parametric equations. To develop 'the haptic primitive', we adopted "the God-Object Method" as a haptic rendering algorithm and applied 'Constructive Solid Geometry' to manage haptic objects. Besides being used in the 'ghost library' of $PHANToMTM^{TM}$ our method can be used as a basic component for developing tools and libraries that aim to simplify haptic modeling. It can also be applied to tactile display modules and temporal display modules. Ultimately it can be developed into a one-stop haptic modeling tool that enables the user to more conveniently create a tangible CAD systems or a tangible e-ommerce system.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.93-100
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• 1993

This study was carried out to investigate the relationship between the traffic signal systmes and the air pollutants emitted by the motor vehicles at Kangnam Intersection. One of the most important measures of effectiveness (MOE) in traffic studies is the delay to vehicles in the system. Delay represents indirect costs to the motorist in terms of time loss and a direct cost in terms of fuel consumption during idling. The results of TRANSYT-7F modeling was correlated among delay, fuel consumption and total travel tiem. Air pollutants emission rate can be calculated by the results of modeling and the Korean type emission factor. As expected the highest emissions, for air pollutants, are observed during the morning rush hours (07 : 00-10 : 00). For better results of modeling, the TRANSYT-7F model needs to modify for the Korean type of traffic model. The results of this study indicate that the variation of air pollutants emission rates were closely related to the traffic signal system.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.8-12
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• 2003

The centrifuge test result on capped sediment was compared to the advection- dispersion equation proposed for one layered to predict contaminant transport parameters. The fitted contaminant transport parameters for the centrifuge test results were one to three orders of magnitude greater than the estimated parameters from the advection-dispersion equation. This indicates that the centrifuge model over estimated the contaminant transport phenomena. Thus, the centrifuge provides a non-conservative approach to modeling contaminant transport. It should be also noted that the advection-dispersion equation used in this study is a one layered model. Two layered modeling approaches are more appropriate for modeling this data since there are two layers with different partitioning coefficients. Further research is required to model the centrifuge test using two-layered advection-dispersion models.

• Research in Mathematical Education
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• v.7 no.4
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• pp.247-270
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• 2003

The purpose of this study is to build a model that explains the relationship between and among five variables that are student background, teacher background, home environment, school characteristic, and student mathematics achievement, using structural equation modeling. Another purpose of this study is to compare the relationships of these variables between the United States and Korea in 7th and 8th grades mathematics. Student, teacher, and school background files from population 2 in the TIMSS were selected for this study. The result of the study provides practical information for teachers, parents, school principals, and other people who are interested in improving student achievement, and also provides the information that may explain differences and similarities between the US and Korea in mathematics achievement.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.7B
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• pp.1279-1288
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• 1999

DEVSim++ is a C++ based, object-oriented modeling/simulation environment which realizes the hierarchical, modular DEVS formalism for discrete event systems specification. The paper describes a methodology for performance modeling and analysis of an ATM-based network system within the DEVSim++ environment. The methodology develops performance models for the system using the DEVS framework and implement the models in C++. Performance indices measured are the length of queues located at connection of the system and cell waiting times with respect to QoS grades for a network bandwidth of 155 Mbps.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.133-136
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• 2000

Soil decontamination process was conducted to study adsorption and modeling characteristic of Sr$^{2+}$ ion using citric acid and water system with TRIGA soil. When the concentration of citric acid was increased, the BTC of Sr$^{2+}$ ion was to be closed to the BTC of $^3$$H_2O$ at experiments of soil adsorption. Beside, when the concentration of citric acid was under 0.01M Sr$^{2+}$ ion, BTLs was asymmetry. It was characteristic of nonequilibrium adsorption. R and $K_{p}$ , were decreased to be increased the concentration of citric acid. Asymmetry modeling was nearly the same to be compare with symmetry modeling in decontamination process, when the concentration of citric acid was decreased. Result of experiment was agree with asymmetry and symmetry model, when the concentration of citric acid was increased.eased.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.2
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• pp.88-98
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• 1992

Real automobiles have been utilized to study the occupant behaviors and the response of the structures in the crash environment. Since various parameters are involved in the automobile crashworthiness, a number of experiments must be conducted. The experiments have been contributed to increasing the cost due to the fact that the test is quite expensive. Therefore, computer simulation is adopted to reduce the number of experiments. A few computer programs have been developed specifically to solve the occupant responses in the crash environment. In this research, a software is used to study the occupant dynamic analysis. A modeling of occupant analysis is established for a passenger car and the results are verified through comparisons with real experiments. In the modeling, data are tuned very carefully so that simulated results such as HIC(Head Injury Criterion) and acceleration of each body may approximate to the experimental results. The compared experiment is a barrier test which is carried out by frontal impact. A feedback to the design process is suggested from the result of this research.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.6
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• pp.563-576
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• 1998

To study the influences of the emission sources during lune 13∼15 1997 in Seoul, MESOPVFF II model has been used. The MESOPVFF II model includes terrain effects, chemical transformation and removal processes. Data of 20 surface meteorological stations and the upper air station on mid-west area in Korea were used as a DWM (Diagnostic Wind Model) input data. This model is likely to be applicable because the predicted SO2 concentration was well matched with measured 502 concentration in Seoul and Kyonggido. In generally air pollutants in Seoul have major influence on the other cities but the result of modeling appeared also air pollutants of the other cities influence on Seoul. Finally, in the case of calculating the air quality by diffusion model, the influences of air pollutants emitted in metropolitan area as well as the emission rate in modeling area should be considered.