• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.231-240
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• 2007

This paper presents an advanced modeling and simulation technique applied to DC/DC power electronic converters fed through renewable energy power sources. The distributed generation (DG) system at the Illinois Institute of Technology, which employs a phase-l system consisting of a photovoltaic-based power system and a phase-2 system consisting of a fuel cell based primary power source, is studied. The modeling and simulation of the DG system is done using the generalized state space averaging (GSSA) method. Furthermore, the paper compares the results achieved upon simulation of the specific GSSA models with those of popular computer aided design software simulations performed on the same system. Finally, the GSSA and CAD software simulation results are accompanied with test results achieved via experimentation on both, the PV-based phase-l system and the fuel cell based phase-2 power system.

• IE interfaces
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• v.15 no.1
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• pp.55-63
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• 2002

This paper utilizes the FIDO methodology (Function, Information, Dynamic, Organization modeling) which is an enterprise modeling tool that can describe inter-organizational interaction (specifically between prime and sub contractors in this experiment). FIDO follows the standard IDEFO rules in order to demonstrate how a cascading information flow can evolve from a customer to a prime to a subcontractor in a concurrent manner, in a supply chain environment. Background on these processes is presented, followed with the newly derived process and methodology. This is presented in a supply chain management context, and results from an actual experiment at Motorola utilizing subcontractors that supply custom machine parts is presented and reviewed.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.542-557
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• 2007

Contamination of subsurface results in degradation of geomaterials (i.e., soils and rock mass), in the long run. This is mainly due to the presence of chemical and/or radiological materials in undesirable concentrations and at elevated temperatures. However, as contaminant-geomaterial interaction is an extremely slow and complex process, which primarily depends on their physical, chemical and mineralogical properties, it is quite difficult to study this interaction under laboratory or in situ conditions. In such a situation, accelerated physical modeling, using a geotechnical centrifuge, and finite element/difference based numerical modeling techniques are found to be quite useful. This paper presents details of various modeling techniques developed by the researchers at the Indian Institute of Technology Bombay, Mumbai, India, for studying heat migration, flow and interaction (fate) of reactive and non-reactive contaminants in the geoenvironment, under saturated and unsaturated conditions. In addition, paper presents details of the technique that can be employed for determining susceptibility of a material to undergo physico-chemico-mineralogical alterations due to its interaction with contaminants.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.752-757
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• 1991

Recently, human body modeling with muscle deformation has become an attractive research area in computer animation. There are many modeling tools available for solids such as mechanical part. However, there are many limitations of these conventional methods in modeling flexible objects with delicate motions and shapes such as human bodies. In this paper we present a new modeling technique for human body with muscle deformation. Each muscle is represented as a generalized cylinder and its shape deformation is computed using simple algorithm. The human body is a union of muscles, bones, organs, etc. The modeling data are obtained from the information on the human anatomy. To demonstrate the feasibility of our method, we model several arm muscles and simulate the skin deformation. As a result we have obtained a realistic shape deformation.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.160-166
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• 2003

Interest in advanced vehicles results in correspondingly increased interest in modeling and simulation of the dynamic behavior of Maglev-type vehicle systems. DADS is a program especially suited for the analysis of multibody mechanical systems. This paper demonstrates the application of DADS to the dynamic modeling and simulation of such advanced vehicles. A brief description is made of the modeling requirements of magnetically levitated systems, along with a summary of some of the related capabilities of DADS. As a case study, an analysis of a vehicle based on the UTM01 system is presented. This paper shows that the presented modeling technique is applicable to the dynamic characteristics evaluation and control law design of Maglev- type vehicles.

• Korean Journal of Computational Design and Engineering
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• v.16 no.2
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• pp.114-125
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• 2011

Construction industries worldwide have moved to Building Information Modeling environment in conjunction with IT technology progress. Korean domestic construction market is in the midst of enthusiastically adopting BIM technique and the public sectors try to apply the method to their projects. Difficulties have been introduced, however, in doing so mainly due to the complexity in reflecting the distinctions of the public cost estimate requirements to BIM modeling. The main objective of this study is to propose four kinds of BIM property information modeling methodologies which would be used in the quantity surveys of the public construction projects. To evaluate the applicability of the suggested modeling methods, the research performed a case study.

• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.2
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• pp.91-103
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• 2003

Use case modeling on UML (Unified Modeling Language) is getting widely used in OOAD and CBD and it is considered a useful technique in dealing with the complexity of the requirements analysis. However, some of the problems with use case modeling are that it is not structured, difficult to handle non-functional requirements, and to analyze impacts among use cases. To alleviate these problems, we propose a scenario-based goal-oriented approach for use case modeling. The proposed approach is to apply a goal-oriented analysis method to use case modeling. Since goal-oriented analysis method is not systematic and many heuristics are involved, we have adopted scenarios as the basis for goal extraction. The proposed method is applied to CBIS (City Bus Information Subsystem) in ITS (Intelligent Transportation System) domain. The proposed approach helps software engineers to analyze the impact among use cases and represent non-functional requirements.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.84-96
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• 2021

Certainly, the success of the Unified Modeling Language (UML) as the de facto standard for modeling software systems does not imply closing the door on scientific exploration or experimentation with modeling in the field. Continuing studies in this area can produce theoretical results that strengthen UML as the leading modeling language. Recently, a new modeling technique has been proposed called thinging machine (TM) modeling. This paper utilizes TM to further understand UML, with two objectives: (a) Fine issues in UML are studied, including theoretical notions such as events, objects, actions, activities, etc. Specifically, TM can be used to solve problems related to internal cross-diagram integration. (b) TM applies a different method of conceptualization, including building a model on one-category ontology in contrast to the object-oriented paradigm. The long-term objective of this study is to explore the possibility of TM complementing certain aspects in the UML methodology to develop and design software systems. Accordingly, we alternate between UML and TM modeling. A sample UML model is redesigned in TM, and then UML diagrams are extracted from TM. The results clarify many notions in both models. Particularly, the TM behavioral specification seems to be applicable in UML.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.7
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• pp.702-708
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• 2010

Reaction wheel assemblies(RWA) are expected to be one of the largest high frequency disturbance sources to the optical payload of satellites. To ensure the tight pointing-stability budget and high image quality of satellites, a vibration isolation device should be applied to the main disturbances. For developing the isolating system, the disturbances need to be identified and modeled accurately. In the present study, a modeling technique of RWA and its disturbance was described. The micro-vibration disturbances were generated numerically by using an analytical wheel and disturbance model. The parameter estimation scheme of the model was suggested, and the RWA and disturbance modeling technique was verified through the numerical example analysis. The analytical results show that the wheel and disturbance model can be accurately established by using the modeling technique proposed in the present study. The wheel and disturbance model is expected to be useful for development of the RWA isolator system.

• Journal of the Korea Concrete Institute
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• v.26 no.5
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• pp.599-606
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• 2014

Since progressive collapse of tall buildings can cause enormous damage, it should be considered during the design phase of tall buildings. The progressive collapse analysis of tall buildings using finite element methods is almost impossible due to the vast amount of computing time. In this paper, applied element method was evaluated as an alternative to the finite element method. Reduced DOFs modeling technique was proposed to enable the progressive collapse analysis of tall buildings. The reduced DOFs model include only the part which is subjected to direct damage from blast load and the structural properties such as mass, transferred load and stiffness of excluded parts are accumulated into the top story of the reduced DOFs model. The proposed modeling technique was applied to the progressive collapse analysis of 20-story RC building using three collapse scenarios. The reduced DOFs model showed similar collapse behavior to the whole model while the computing time was reduced by 30%. The proposed modeling technique can be utilized in the progressive collapse analysis of tall buildings due to abnormal loads.