• Resources Recycling
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• v.9 no.2
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• pp.26-32
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• 2000

A period of widespread damage to the surroundings by acid mine drainage was examined by modeling using column device, and the method to solve this problem was worked out. the underlying principle is to let the tailings permanently maintain a stable state not being reacted with the underground water, and the method is that the tailings and limestone are piled up alternatively. This reclamation method is economic and environmentally useful because of practical use of a large amount of low-grade natural limestone.

• Structural Engineering and Mechanics
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• v.46 no.1
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• pp.91-110
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• 2013

This paper proposes a novel iterative procedure for the design of planar reinforced concrete structures in which the reinforcement is designed for stresses calculated in a nonlinear finite element analysis. The procedure is intended as an alternative to strut and tie modeling for the design of complex structures like deep beams with openings. Practical reinforcement arrangements are achieved by grouping the reinforcement into user defined horizontal and vertical bands. Two alternative strategies are proposed for designing the reinforcement which are designated A and B. Design constraints are specified in terms of permissible stresses and strains in the reinforcement and strains in the concrete. A case study of a deep beam with an opening is presented to illustrate the method. Comparisons are made between design strategies A and B of which B is shown to be most efficient. The resulting reinforcement weights are also shown to compare favorably with those previously reported in the literature.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.58-60
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• 2000

This paper presents the modeling methods to analyze the static and dynamic performances for practical power system loads using field measurement data. Also, it is included that the several modeling techniques using EMTDC program and field measuring method for real static dynamic loads. As a result of this study, through the comparisons between simulation results and measurement data, typical parameters of static and dynamic loads according to the variation of system voltage and frequency are given.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.289-292
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• 2010

In this paper we proposed web-based educational multimedia contents development method using Web 3D technology and implemented web 3D contents for use at the education field. A implementation of contents is composed of modeling to specific entity in 3D shape, convert modeling data to enable data at web and include in webpage. A practical use of contents on this research can provide more advanced user experience and immersion.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1412-1417
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• 2009

BIM(Building Information Modeling) is considered a new paradigm and a powerful method in building design, construction and maintenance. However, it is still hard to implement environmental performance analysis using BIM in design stages. This study aims to reveal practical problems and evaluate interoperability between building design information and performance analysis with case studies. Three case studies are performed using two environmental analysis programs (IES/VE, EnergyPlus) and BIM-based architectural design programs (Revit, GoogleSketchUp) in this paper.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.4
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• pp.338-345
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• 1998

The mathematical interpretation of a practical sampler which is useful to obtain the small signal models for the peak and average current mode controls is proposed. Due to the difficulties in applying the Shannons sampling theorem to the analysis of sampling effects embedded in the current mode control, several different approaches have been reported. However, these approaches require the information of the inductor current in a discrete expression, which restricts the application of the reported method only to the peak current mode control. In this paper, the mathematical expressions of sampling effects on a current loop which can directly apply the Shannons sampling theorem are newly proposed, and applied to the modeling of the peak current mode control. By the newly derived models of a practial smapler, the models in a discrete time domain and a continuous time domain are obtained. It is expected that the derived models are useful for the control loop design of power supplies. The effectiveness of the derived models are verified through the simulation and experimental results.

• Structural Engineering and Mechanics
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• v.12 no.6
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• pp.633-656
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• 2001

In this paper, modal control with direct output feedback is formulated in a systematic manner for easy implementation. Its application to the seismic protection of structural systems is verified by a shaking table test, which involves a full-scale building model and an active bracing system as the control device. Two modal control cases, namely, one full-state feedback and one direct output feedback control were tested and compared. The experimental result shows that in mitigating the seismic response of building structures, modal control with direct output feedback can be as effective and efficient as that with full-state feedback control. For practical concerns, the control performance of the proposed method in the presence of sensor noise and stiffness modeling error was also investigated. The numerical result shows that although the control force may be increased, the maximum floor displacements of the controlled structure are very insensitive to sensor noise and modeling error.

• Computers and Concrete
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• v.16 no.4
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• pp.569-585
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• 2015

Various computational tools are available for modeling highly nonlinear structural engineering problems that lack a precise analytical theory or understanding of the phenomena involved. This paper adopts a fairly simple nonparametric adaptive regression algorithm known as multivariate adaptive regression splines (MARS) to model the nonlinear interactions between variables. The MARS method makes no specific assumptions about the underlying functional relationship between the input variables and the response. Details of MARS methodology and its associated procedures are introduced first, followed by a number of examples including three practical structural engineering problems. These examples indicate that accuracy of the MARS prediction approach. Additionally, MARS is able to assess the relative importance of the designed variables. As MARS explicitly defines the intervals for the input variables, the model enables engineers to have an insight and understanding of where significant changes in the data may occur. An example is also presented to demonstrate how the MARS developed model can be used to carry out structural reliability analysis.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.267-273
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• 2013

Early design phase energy modeling is used to provide the design team with first order of magnitude feedback about the impact of various building configurations. For better energy-conscious and sustainable building design and operation, the construction of BIM data interoperability for energy performance assessment in the early design phase is important. The purpose of this study is to suggest construction of BIM data interoperability for energy performance assessment based on BIM. To archive this purpose, the authors have investigated advantage of BIM-based energy performance assessment through comparison with traditional energy performance assessment and suggested requirement for construction of open BIM environment such as BIM data creation, BIM data software practical use, BIM data application and verification. In addition, the authors have suggested BIM data interoperability and BIM energy property mapping method focused on materials.

• Journal of information and communication convergence engineering
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• v.22 no.1
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• pp.23-32
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• 2024

This study aims to improve the quality of distance learning by developing webcast-based e-learning media and integrating it into an e-learning platform for functional job training purposes at the National Research and Innovation Agency, Indonesia. This study uses a Technology Acceptance Model (TAM) to assess and predict user perceptions of information systems using webcast platforms as an alternative to conventional applications. The research method was an online survey using Google Forms. Data collected from 136 respondents involved in practical job training were analyzed using structural equation modeling to test the technology acceptance model. The results showed that the proposed model effectively explained the variables associated with the adoption of web-based e-learning during the COVID-19 pandemic in Indonesia for participants engaged in functional job training. These findings suggest that users' perceptions of ease of use, usefulness, benefits, attitudes, intentions, and webcast usage significantly contribute to the acceptance and use of a more effective and efficient webcast-based e-learning platform.