• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.6
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• pp.367-374
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• 2022

This papter presents the use of the automatic differential method based on the backpropagation method to obtain the design sensitivity and its application to topology optimization considering the stress constraints. Solving topology optimization problems with stress constraints is difficult owing to singularities, the local nature of stress constraints, and nonlinearity with respect to design variables. To solve the singularity problem, the stress relaxation technique is used, and p-norm for stress constraints is applied instead of local stresses for global stress measures. To overcome the nonlinearity of the design variables in stress constraint problems, it is important to analytically obtain the exact design sensitivity. In conventional topology optimization, design sensitivity is obtained efficiently and accurately using the adjoint variable method; however, obtaining the design sensitivity analytically and additionally solving the adjoint equation is difficult. To address this problem, the design sensitivity is obtained using a backpropagation technique that is used to determine optimal weights and biases in the artificial neural network, and it is applied to the topology optimization with the stress constraints. The backpropagation technique is used in automatic differentiation and can simplify the calculation of the design sensitivity for the objectives or constraint functions without complicated analytical derivations. In addition, the backpropagation process is more computationally efficient than solving adjoint equations in sensitivity calculations.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.313-322
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• 2022

The number of architects who adopt BIM(Building Information Modeling) as the design method are gradually increasing because of its productivity and efficiency. Climate Change and Global Warming lead to legislation of new energy regulations and strengthen existing ones. The current architectural design methods (2D CAD) take a lot of time and effort to verify energy codes and are hard to adjust according to the design changes. The purpose of this study is to show the effectiveness of the BIM in building envelop energy modeling of the housing project. In the process of design method change, We could contribute to increasing productivity and efficiency in building energy verification through BIM because the updated value could be calculated simultaneously without information omission or recalculation process. The procedure for the study is as follows. Using BIM of the Goldin at Essex Crosing Housing Project by Revit 2011 as a case model, this study analyze the criteria for energy plan to conform to the energy code in NYC. The result value from the setting of the Revit model is compared with the reference value required by the NYC Energy Code. Finally, the data from BIM are entered into COMckeck, the energy verification program provided by U.S. Department of Energy, to check whether the building envelope energy performance conforms to NYC Energy Code.

• KIEAE Journal
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• v.12 no.4
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• pp.105-110
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• 2012

Recently, all of the world are facing with a serious environmental crisis of global warming due to excessive energy consumptions. The Korean Government, taking over 97% of dependence on foreign energy, has made various efforts on reducing energy and greenhouse gas emission under the motto of "Low-Carbon Green Growth". Since the building sector takes 24% of domestic energy consumption, many design standards and regulations on saving energy in new buildings have been established. However, applications of energy saving designs and techniques on the remodeling process at deteriorated buildings including educational ones have been lack. Under a situation where the number of deteriorated schools accounts for up to 50%, this paper evaluated the performances of factors for reducing energy at deteriorated middle school buildings through an energy simulation tool on a standard school model. As a result, among factors of insulation, window's SHGC, southern louver, indoor setup temperature, and system efficiency, all other factors except window's SHGC and southern louver proved contribute to reduce energy at deteriorated middle school buildings, compared with the baseline energy consumption.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.359-366
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• 2005

Most engineering optimization are based on numerical linear and nonlinear programming methods that require substantial gradient information and usually seek to improve the solution in the neighborhood of a starting point. These algorithm, however, reveal a limited approach to complicated real-world optimization problems. If there is more than one local optimum in the problem, the result may depend on the selection of an initial point, and the obtained optimal solution may not necessarily be the global optimum. This paper describes a new harmony search(HS) meta-heuristic algorithm-based approach for structural size optimization problems with continuous design variables. This recently developed HS algorithm is conceptualized using the musical process of searching for a perfect state of harmony. It uses a stochastic random search instead of a gradient search so that derivative information is unnecessary. Two classical space truss optimization problems are presented to demonstrate the effectiveness and robustness of the HS algorithm. The results indicate that the proposed approach is a powerful search and optimization technique that may yield better solutions to structural engineering problems than those obtained using current algorithms.

• Proceedings of the IEEK Conference
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• 2001.06c
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• pp.25-28
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• 2001

RBFN has some problem that because the basis function isn't orthogonal to each others the number of used basis function goes to big. In this reason, the Wavelet Neural Network which uses the orthogonal basis function in the hidden node appears. In this paper, we propose the composition method of the actual function in hidden layer with the scaling function which can represent the region by which the several wavelet can be represented. In this method, we can decrease the size of the network with the pure several wavelet function. In addition to, when we determine the parameters of the scaling function we can process rough approximation and then the network becomes more stable. The other wavelets can be determined by the global solutions which is suitable for the suggested problem using the genetic algorithm and also, we use the back-propagation algorithm in the learning of the weights. In this step, we approximate the target function with fine tuning level. The complex neural network suggested In this paper is a new structure and important simultaneously in the point of handling the determination problem in the wavelet initialization.

• Journal of Distribution Science
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• v.14 no.11
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• pp.5-17
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• 2016

Purpose - The purpose of this study is to establish an conceptual framework to explain the mechanism of internationalization behavior being used by recently established retailer in emerging countries. Research design, data, and methodology - The existing research on retail internationalization has focused on global retailers located in advanced countries which have expanded their business to emerging countries. That is, "internationalization from top to bottom". However, recent years have seen a reversal in this trend, resulting in the emergence of "internationalization from bottom to top" by retailers based in emerging economies. In order to explore this reversal, this study attempts to develop an conceptual framework based on the theories of "innovation" and "retail format". Results - This study found an conceptual framework which was adopted both a concept of "formula" derived from the theory of retail format and a concept of "production and process innovation" derived from the theory of innovation as a core concept. Conclusions - The conceptual framework provided an understanding of how retailers in emerging countries have gained a competitive advantage over retail companies based in countries with advanced economies. It suggested that innovation that gave these companies a competitive edge was caused by competitive interaction which allowed them to expand to oversea markets.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.25
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• pp.243-266
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• 2005

Product liability is becoming a real issue to exporters, manufacturers world wide. The purpose of this study is to examine the product liability of Korean exporters, manufacturers, etc. under Product Liability Laws and Regulations of China. For this purpose, firstly we deal with the Product Liability Laws and Regulations of China. Secondly we analyze the case study concerning the Product Liability in China. From the analysis of case study, Korean exporters, manufacturers, etc. are required to pay close attention to the following : the correspondence of English with Chinese in the warning phrases, the possibility of application of strict global standard in case of existence of product liability, the proper treatment of evidence in the process of litigation, the application of strict liability and the shift of responsibility for evidence on to a defendant, the observance of procedures prescribed by the country in design and manufacture of the product, the manufacture of product to come up to country standard in quality, the consideration of diverse expression in the preparation of warning sign, the importance of quality control and inspection system in case of local procurement of parts and raw materials, Finally, this paper contributes to help the Korean Exporters, Manufacturers, etc. to build up the proper countermeasures regarding product liability under the product liability regulations of China.

• Journal of Korea Multimedia Society
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• v.8 no.1
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• pp.128-136
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• 2005

In this paper, we designed and implemented the general-purpose document repository manager for the ebXML-based e-business framework that support the rapid translation of various types of documents and provide the flexibility corresponding to the framework changes. Also, we automated the manually-processed e-business document translation process by designing the adaptor module for the interoperability of legacy systems. In the regards, our designed general purpose document manager makes it possible to integrate the existing e-commerce systems that are operated on the heterogeneous frameworks, and can be used on global e-business solution.

• Smart Structures and Systems
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• v.1 no.1
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• pp.63-82
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• 2005

This paper introduces a technology for robust and low maintenance cost sensor network capable to detect accelerations below a micro-g in a wide frequency bandwidth (above 1,000 Hz). Sensor networks with such performance are critical for navigation, seismology, acoustic sensing, and for the health monitoring of civil structures. The approach is based on the fabrication of an array of high sensitivity accelerometers, each utilizing Fabry-Perot cavity with wavelength-dependent reflectivity to allow embedded optical detection and serialization. The unique feature of the approach is that no local power source is required for each individual sensor. Instead one global light source is used, providing an input optical signal which propagates through an optical fiber network from sensor-to-sensor. The information from each sensor is embedded onto the transmitted light as an intrinsic wavelength division multiplexed signal. This optical "rainbow" of data is then assessed providing real-time sensing information from each sensor node in the network. This paper introduces the Fabry-Perot based accelerometer and examines its critical features, including the effects of imperfections and resolution estimates. It then presents serialization techniques for the creation of systems of arrayed sensors and examines the effects of serialization on sensor response. Finally, a fabrication process is proposed to create test structures for the critical components of the device, which are dynamically characterized.

• Journal of Distribution Science
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• v.16 no.4
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• pp.35-47
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• 2018

Purpose - This study seeks to find out the factors affecting the performance of franchisees from the franchisor's and franchise's intangible assets. In order to explain the process, this study explores the concept of LMX, Relational Capital, and Decision Rights Delegation. Research design, data, and methodology - To verify the proposed hypotheses, a questionnaire survey was conducted for franchise store owners, and to test the hypotheses, structural equation modeling was established. Results - First, franchisor's intangible assets affect the quality of LMX, but don't affect the relational capital. And the quality of LMX affects the relational capital. In addition, "the effect of delegation of decision rights on relational capital" and "the effect of relational capital on franchisee's performance" were significant. However, the effect of delegation of decision rights on franchisee's performance wasn't significant. Second, the intangible assets of the franchise have a positive effect on the quality of the LMX and the degree of delegation of decision rights, and the quality of the LMX has a positive effect on the delegation of decision rights. Conclusions - This study would suggest operational implications for the formation of vertical and horizontal relationships and the cooperation between the main members of the franchise business.