• Journal of Positioning, Navigation, and Timing
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• v.5 no.2
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• pp.47-57
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• 2016

Since the Global Navigation Satellite System (GNSS) may not provide navigation information due to external interferences, many countries have plans to prepare a backup system for this situation. One of the possible GNSS backup systems is a multiple radio positioning integration system in combination with the terrestrial radio navigation system. Before constructing such a GNSS backup system, M&S software is needed to analyze if the system satisfies the performance the required navigation performance. This study presents requirements of M&S software for coverage analysis of the navigation system, and proposes an M&S software design scheme on the basis of the requirements. The M&S software is implemented, and coverage analysis is performed to verify the validity of the proposed design scheme.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.725-731
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• 2009

Construction documents are recognized as an essential component for making a decision and supporting on construction processes. In construction, the management of project document is a complex process due to different factors such as document types, stakeholder involvement, document flow, and document flow processes. Therefore, inappropriate management of project documents can cause several impacts on construction work processes such as delay or poor quality of work. Several information and communication technologies (ICT) were proposed to overcome problems concerning document management practice in construction projects. However, the adoption of ICT may have some limitation on the compatibility of specific document workflow. Lack of understanding on designing document system may cause many problems during the use and implementation phase. Thus, this paper proposes the framework that integrates Soft System Methodology (SSM) concept and Integrated Definition Modeling Technique (IDEF) for analyzing document management system in construction project. Research methodology is classified as the case study. Five main construction building projects are selected as case studies. The qualitative data related to problems and processes are collected by interviewing construction project participants such as main contractors, owners, consultants, and designers. The findings from case study show the benefits of using SSM and IDEF. The use of SSM can help identify the problems in managing construction document in rich picture view whereas IDEF can illustrate the document flow in construction project in details. In addition, the idea of integrating these two concepts can be used to identify the root causes of process problems at the information level. As the results, this idea can be applied to analyze and design web-based document management system in the future.

• Journal of Ubiquitous Convergence Technology
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• v.2 no.2
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• pp.105-110
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• 2008

The definition of the program control is introduced on the theory of the basis of the first integrals SDE system. That definition allows constructing the program control gives opportunity to stochastic system to remain on the given dynamic variety. The program control is considered in terms of dynamically invariant for stochastic process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.130-131
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• 2015

Accurate construction progress measurement is an important issue for successful project delivery. This paper presents a method that keeps track of the progress measurement involved in construction operations and facilities visualization of the data using BIM and IOT. To verify the method, a residential house project was used for the case study. Test case verifies the usability and validity of the method implemented in the system.

• IE interfaces
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• v.2 no.2
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• pp.33-50
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• 1989

The notions of office automation and systems modelling are integrated into information and decision flows of university administration. The automated university information system developed here will enhance efficiency of work, accuracy and timeliness of information, and correctness of decisions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.1038-1046
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• 2004

In order to acquire high-speed and high-precision performances in servomechanisms, an integrated design method have been proposed. Based on strict mathematical modeling and analysis of system performance according to design and operating parameters, a nonlinear constrained optimization problem including the relevant subsystem parameters of the servomechanism is formulated. Optimum design results of mechanical and electrical parameters are obtained according to the design parameters specified by designers through the integrated design processes. Motors are optimally selected from the servo motor database. Both the geometric errors referring to Abbe offset and the contour errors are minimized while required constraints such as stability conditions and saturated conditions are satisfied. This design methodology both offers the improved possibility to evaluate and optimize the dynamic motion performance of the servomechanism and improves the quality of the design process to achieve the required performance for high-speed/precision servomechanisms.

• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.239-241
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• 2008

A powered system with fuel cell is regarded as a high current and low voltage source. Effects of the loads on the electrical power source are important to optimize the integrated power system. The design parameters of the system should be chosen by taking into account the characteristics of the fuel cell, so the costs of the power system at given operating conditions can be reduced. Furthermore, the dynamics characteristic of the system is crucial to acquire performance in applications, particularly interactions between loads and the fuel cell system. Currently, no integrated simulation has been approached to analyze interrelated effects. Therefore, the dynamic models of power conversion system with a PEM fuel cell that includes the PEM fuel cell stack, DC/DC converter and associated controls is developed. Electric lads for the system are derived by using a power theory that separates a load current into active, reactive, distortion or a mixed current component. Dependency of the DC capacitor on the loads are analyzed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1759-1769
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• 1989

This paper presents the development of a simulator for an industrial robot. The simulator is characterized by a fully integrated dynamic model and a hardware oriented control scheme. The dynamic model includes the actuator dynamics as well as the manipulator dynamics to integrate the entire dynamics of the robot system. On the other hand, the control scheme is oriented as a hardware structure which is usually implemented in the industrial robot. That is to say, a conventional PI control law is used to regulate the position, the speed, and the current. A Pulse Wave Modulation (PWM)generator modulates the supplied voltage to the actuator. Since the simulator is consistent with the industrial robot system, it provides the essential design concepts for the development process of the robot. In practice, the simulator is applied to the SCARA robot which has been developed in GSIS. Here, it investigates the characteristics and performance of the robot with changing design parameters. Thus, the investigation furnishes criteria for the selection of acfuator, control gain, trajectory planning, etc.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.04a
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• pp.50-55
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• 1991

This paper presents database technique for an computer-integrated structural design system of buildings. Network database designed to support all the processes of structural design, such as, planning, modelling, analysis, member design and redesign processes etc. stores all information from user input and system results effectively and so provides centeral communication area between applications. The user interface wi th interactive and batch modes plays roles of building modeler including conventional pre-processor and post-processor. The concepts of 'Planar Surface Modeling' and 'Geometry Zoning' are defined for easy construction of building model. The concept presented in this paper will save the time and memory required for model generation and contribute to data consistency, thus leave a designer more time actually performing the analyses and interpreting the results. The formulation of automating the process of bulilding model ins and structural analysis is the key to study.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.455-462
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• 1998

Analysis and design of vibrating machine foundations subjected to dynamic loads is a very complex problem. Thus it is difficult to set up an accurate analytical modeling. Generally, the design of foundations for vibrating machines has been performed by the equivalent static analysis which is generally based on engineer's experience and various assumptions The purpose of this study is to develop an integrated system which enables structural engineers to produce results of high quality within a short time in works related to structural analysis and design of foundation for vibrating machines. As the result of this study, level-up of application software is expected as well as improvement of quality in structural engineering and reduction of engineers' effort.