• Structural Engineering and Mechanics
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• 제38권3호
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• pp.283-300
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• 2011

A new conception of fundamental tasks in dynamics of the bridge-track-train systems (BTT), with the aim to evaluate moving load's models adequacy, has been developed. The 2D physical models of BTT systems, corresponding to the fundamental tasks, have been worked out taking into account one-way constraints between the moving unsprung masses and the track. A method for deriving the implicit equations of motion, governing vibrations of BTT systems' models, as well as algorithms for numerical integration of these equations, leading to the solutions of high accuracy and relatively short times of simulations, have been also developed. The derived equations and formulated algorithms constitute the basis for numerical simulation of vibrations of the considered systems.

• Research in Mathematical Education
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• 제27권3호
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• pp.409-430
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• 2024

In this paper, we describe a framework developed by synthesizing and combining scholarship from the fields of equity in mathematics education and effective integration of technology in the classroom. This framework allows researchers, educators, and teachers to examine the potential of technology-enhanced mathematics lessons to advance equity along six identified dimensions. We share a case study of a research lesson that applied this framework and implemented technology as an equity lever by allowing students to explore social justice issues using a suite of technology tools. Implications for mathematics teacher educators and researchers are discussed as ways the framework can be used to promote the equitable integration of technology.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• 제2권3호
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• pp.103-122
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• 2007

Innovation clusters developed or evolved around a specific region IS the key element of national innovation system and determine national competitiveness. Recognizing the importance of innovation clusters, Korean government has made "Daedeok Special R&D Zone" in 2005. This paper examines the success factors of famous Cluster in advanced countries and China, and proposes the strategy for regional development in Daejeon through boosting Daedeok Innovation Cluster. Although 30.5% of government R&D investment is being concentrated in Daedeok along with 10% of the country's doctorate degree holders, it is lack of increasing revenue by linking corporate R&D with a creative and challenging entrepreneur spirit. The core of the innovation cluster is the integration and mutual networking of the main participants. This paper suggests strategies for developing as a world class innovation cluster, global networking and clustering, venture ecosystem formation, commercialization the knowledge by interacting with market. It also explains the necessity of regional integration for cluster to cluster linkages in the East Asia Region.

• Journal of the Microelectronics and Packaging Society
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• 제24권1호
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• pp.35-43
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• 2017

The three-dimensional integrated circuit (3D-IC) is a general trend for the miniaturized and high-performance electronic devices. The through-silicon-via (TSV) is the advanced interconnection method to achieve 3D integration, which uses vertical metal via through silicon substrate. However, the TSV based 3D-IC undergoes severe thermo-mechanical stress due to the CTE (coefficient of thermal expansion) mismatch between via and silicon. The thermo-mechanical stress induces mechanical failure on silicon and silicon-via interface, which reduces the device reliability. In this paper, the thermo-mechanical reliability of TSV based 3D-IC is reviewed in terms of mechanical fracture, heat conduction, and material characteristic. Furthermore, the state of the art via-level and package-level design techniques are introduced to improve the reliability of TSV based 3D-IC.

• Research in Mathematical Education
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• 제27권3호
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• pp.401-408
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• 2024

New technological advancements that are available in price and usability for K-12 classrooms result in new content areas to be explored and advancement of previous content area struggles. Visualizations of two-dimensional (2D) representations of three-dimensional (3D) figures and the actual 3D figure is a struggle not only limited to mathematics teaching and learning. However, if this struggle can be rectified and potentially improved through mathematics teaching and learning, the broader impacts of this extends beyond classroom mathematics. New 3D modeling software and 3D printers allow users to easily create and share models or download 3D models from online resources and print them to manipulate in their hand. There is plenty of literature now on classroom use of 3D modeling and printing. This article serves to build onto Ball and Stacey's (2005) suggestions for judicious use of calculators and computer software to address the judicious use of 3D modeling and printing technology for teaching mathematics for student learning. We discuss the following teaching strategies: promote careful decision making about 3D modeling and/or printing use, integrate 3D modeling and or printing into the curriculum, tactically restrict use of 3D modeling and or printing, and promote habits of spatial visualization.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제30권1호
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• pp.71-76
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• 2017

In BIM design, the construction and use of a library are very important. Since the existing contents can be re-used, the design can be executed more effectively and efficiently. Unlike the construction, the civil engineering, in particular, the railroad sees an inappropriate development and standardization of libraries. Thus, this study aims to develop and standardize the 3D object library in the railroad facility. We first gather and analyze the railroad facility breakdown structure and relevant drawings. We then match the items of analyzed standard drawings and the breakdown structure items. It was reviewed whether the library was required according to all items, and if required, it was reviewed what software was proper. Available software were found to be Civil 3D, Revit, etc. Based on this analysis, we will design the attribute items and specifications of the 3D railroad infrastructure library, as well as construct the library thereof.

• Journal of the Korean Society of Visualization
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• 제21권2호
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• pp.14-23
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• 2023

The pressure difference across stenotic blood vessels is a commonly used clinical metric for diagnosing many cardiovascular diseases. At present, most clinical pressure measurements rely solely on invasive catheterization. In this study, we propose a novel method for non-invasive pressure estimation using the incompressible Navier-Stokes equations and a 3D multi-path integration approach. We verify spatio-temporal convergence on an in-silico dataset of a cylindrical straight pipe phantom with steady and pulsatile flow fields. We then evaluate the proposed method on an in vitro dataset of reconstructed control, pre-operative, and post-operative carotid artery cases acquired from 4D flow MRI. The performance of our method is compared to existing approaches based on the pressure Poisson equation and work-energy relative pressure. The results demonstrate the proposed method's high accuracy, robustness to spatio-temporal subsampling, and reduced sensitivity to noise, highlighting its great potential for non-invasive pressure estimation.

• International conference on construction engineering and project management
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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• pp.242-244
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• 2017

Excavation for construction is implemented in natural geographical terrain using a variety of construction equipment. Therefore, 3D excavation simulation requires integration of geographical and equipment modeling. This paper proposes a technique that integrates geographical and equipment modeling for 3D simulations of construction excavation. The geographical model uses a digital map to show ground surface changes during excavation and the equipment model shows equipment movement and placement. This combination produced a state of the art 3D simulation environment that can be used for machine guidance. An equipment operator can use the 3D excavation simulation to help construction equipment operators with decisions during excavation work and consequently improve productivity.

• Journal of The Korean Digital Architecture Interior Association
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• 제1권1호
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• pp.39-45
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• 2001

The purpose of this study is to suggest the possibility which can use as instrument of design by CAD system. And it proposes how makes 3D object model through 2D Drawings in Design process. This study has review the 'Study Drawing' in design process, and application method of CAD as the Architectural Design Integration System. The Architecture can work in ani of the traditional 2D representations as well as in 3D and immediate visual feedback of his work in isometric and perspective projrctions.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제17권4호
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• pp.129-137
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• 2016

BIM libraries for architectural projects have been developed and distributed. However, they do not define physical and logical quality control methods for individual library objects, so there are some difficulties in securing reliability of 3D library models converted from 2D drawings. Because the BIM library contents can be built by participating material and member-fabrication companies, after making individual BIM library objects, a certification process through separate quality verification is very important when delivering as-built BIM libraries. Since the BIM library should have generality for usage, it is necessary to secure the quality of BIM library objects according to consistent verification standards. Therefore, this study suggests a quality verification method for certifying a BIM library object from physical and data perspectives by comparing existing 2D drawings in the BIM libraries built based on standardized 2D drawings from MOLIT. This method could be widely used for quality verification in delivering BIM libraries by companies in the construction sector and operated with rule set data for quality verification of as-built BIM models.