• Korean Journal of Computational Design and Engineering
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• v.10 no.1
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• pp.61-69
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• 2005

In the global ship structure and vibration analysis, the FE(finite element) analysis model is required in the early design stage before the 3D CAD model is defined. And the analysis model generation process is a time-consuming job and takes much more time than the engineering work itself. In particular, ship structure has too many associated structural members such as stringers, stiffness and girders etc. These structural members should be satisfied as the constraints in analysis modeling. Therefore it is necessary to support generation of analysis model with satisfying these constraints as an automatic manner. For the effective support of the global ship analysis modeling, a method to generate analysis model using initial design information within ship design process, that hull form offset data and compartment data, is developed. In order to easily handle initial design information and FE model information, flexible data structure is proposed. An automatic quadrilateral mesh generation algorithm using initial design information to satisfy the constraints imposed on the ship structure is also proposed. The proposed data structure and mesh generation algorithm are applied for the various type of vessels for the usability test. Through this test, we have verified the stability and usefulness of this system including mesh generation algorithm.

• International Journal of Contents
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• v.18 no.3
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• pp.49-57
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• 2022

The purpose of this study was to investigate the satisfaction of personnel selection process according to type of personnel manager and to examine whether the relationship between the type of personnel manager and the satisfaction with the personnel selection process was moderated by the applicant's perception of procedural justice. This study was conducted using a between-group design with 208 students from a four-year university in Korea. One group watched a video in which a human personnel manager selected employees and the other group watched a video in which an AI personnel manager selected employees. Participants were randomly assigned to a condition, responded to a demographic questionnaire, and answered measures of procedural justice and satisfaction with personnel selection after watching the video. As a result, the selection process satisfaction was significantly higher when the human personnel manager conducted the selection process than when the AI personnel manager conducted such process. In addition, when procedural justice was perceived as low, there was a significant difference in satisfaction between human and AI groups. However, when procedural justice was perceived as high, there was no significant difference in satisfaction between the two groups. Based on study results, the significance and limitations of this study and suggestions for future studies are discussed.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.2
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• pp.268-283
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• 2016

Aircraft manufacturing companies have to consider multiple derivatives to satisfy various market requirements. They modify or extend an existing aircraft to meet new market demands while keeping the development time and cost to a minimum. Many researchers have studied the derivative design process, but these research efforts consider baseline and derivative designs together, while using the whole set of design variables. Therefore, an efficient process that can reduce cost and time for aircraft derivative design is needed. In this research, a more efficient design process is proposed which obtains global changes from local changes in aircraft design in order to develop aircraft derivatives efficiently. Sensitivity analysis was introduced to remove unnecessary design variables that have a low impact on the objective function. This prevented wasting computational effort and time on low priority variables for design requirements and objectives. Additionally, uncertainty from the fidelity of analysis tools was considered in design optimization to increase the probability of optimization results. The Reliability Based Design Optimization (RBDO) and Possibility Based Design Optimization (PBDO) methods were proposed to handle the uncertainty in aircraft conceptual design optimization. In this paper, Collaborative Optimization (CO) based framework with RBDO and PBDO was implemented to consider uncertainty. The proposed method was applied for civil jet aircraft derivative design that increases cruise range and the number of passengers. The proposed process provided deterministic design optimization, RBDO, and PBDO results for given requirements.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.57-65
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• 2009

An efficient and high-fidelity design approach for wing-body shape optimization is presented. Depending on the size of design space and the number of design of variable, aerodynamic shape optimization process is carried out via different optimization strategies at each design stage. In the first stage, global optimization techniques are applied to planform design with a few geometric design variables. In the second stage, local optimization techniques are used for wing surface design with a lot of design variables to maintain a sufficient design space with a high DOF (Degree of Freedom) geometric change. For global optimization, Kriging method in conjunction with Genetic Algorithm (GA) is used. Asearching algorithm of EI (Expected Improvement) points is introduced to enhance the quality of global optimization for the wing-planform design. For local optimization, a discrete adjoint method is adopted. By the successive combination of global and local optimization techniques, drag minimization is performed for a multi-body aircraft configuration while maintaining the baseline lift and the wing weight at the same time. Through the design process, performances of the test models are remarkably improved in comparison with the single stage design approach. The performance of the proposed design framework including wing planform design variables can be efficiently evaluated by the drag decomposition method, which can examine the improvement of various drag components, such as induced drag, wave drag, viscous drag and profile drag.

• Korean Journal of Computational Design and Engineering
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• v.15 no.1
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• pp.24-32
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• 2010

This paper introduces a B-spline based branch & bound algorithm for global optimization. The branch & bound is a well-known algorithm paradigm for global optimization, of which key components are the subdivision scheme and the bound calculation scheme. For this, we consider the B-spline hypervolume to approximate an objective function defined in a design space. This model enables us to subdivide the design space, and to compute the upper & lower bound of each subspace where the bound calculation is based on the LHS sampling points. We also describe a search tree to represent the searching process for optimal solution, and explain iteration steps and some conditions necessary to carry out the algorithm. Finally, the performance of the proposed algorithm is examined on some test problems which would cover most difficulties faced in global optimization area. It shows that the proposed algorithm is complete algorithm not using heuristics, provides an approximate global solution within prescribed tolerances, and has the good possibility for large scale NP-hard optimization.

• Journal of The Korean Digital Architecture Interior Association
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• v.13 no.4
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• pp.95-108
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• 2013

The purpose of this study is to analyze and to grasp Peter Calthorpe's urbanism through the process that is compared with various developments of urban design field for the preservation of global environment. From this study, Peter Calthorpe's urbanism for global environment is comprehended according to design stages. As a design goal, He seeks a green urbanism that puts emphasis on land use and transportation. As a urban planning, he devises urban footprint for the tool of evaluation and urban planning, and proposes five place types toward mixed-use development, and advocates Transect for eco-friendly land use. As a urban design, he devises urban network model for transportation network based on accessibility, and devises TOD and TOC model for preventing urban sprawl and mitigating carbon emissions, and advocates TND model for pedestrian-friendly space and community life. He makes importance of urban design. Because he thinks that integrative solution is required to global environment and urban design of integrative characteristic is suitable to preserve global environment. The results of this study are summarized as the followings: First, type classification of urbanism for the preservation of global environment and grasping purposes, methods, characteristics according to the types. Second, grasping characteristics and location of Peter Calthorpe's urbanism as a green urbanism. Third, proposing the direction of improvement for our urban planning and design.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.8
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• pp.1044-1059
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• 2013

The fashion industry has become more interested in sustainable fashion design due to the demand for environmental action based on increased social responsibility awareness and environmentalism. In the current sustainability fashion industry, guidelines for sustainable fashion design are essential. This study suggests guidelines for a sustainable design process based on a theoretical and practical approach. An analysis of several global fashion brands will be applied to the whole apparel design process. This paper will explore the sustainable fashion design process and deal with LCD, as an important factor, by analyzing three global fashion brands: 'H&M', 'NIKE', and 'Levi's'. These three companies are the most active in the area of sustainable performance. The sustainable fashion guidelines will be controlled based on a strategy of practical use in design for sustainable (DFS) fashion industry. The results indicate that the fashion industry has to invest heavily in the future rather than focus on short-term profits; consequently, sustainability is a new growth direction for fashion companies. In addition, the fashion industry should work towards sustainable design under a clear understanding of its goals.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.122-125
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• 2000

The paper describes the adaptation of evolutionary fuzzy model ins (EFM) in developing global function approximation tools for use in genetic algorithm based optimization of nonlinear structural systems. EFM is an optimization process to determine the fuzzy membership parameters for constructing global approximation model in a case where the training data are not sufficiently provided or uncertain information is included in design process. The paper presents the performance of EFM in terms of numbers of fuzzy rules and training data, and then explores the EFM based sizing of automotive component for passenger protection.

• Journal of Information Technology Applications and Management
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• v.14 no.3
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• pp.151-168
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• 2007

RFID is an emerging technology and rapidly applied to various industries due to its high-tech characteristic and convenience. Although RFID provides valuable benefits. it might also generate serious privacy problems. Previous studies show that privacy issues should be incorporated in developing RFID systems and more detailed privacy protection methods. However. they just provide basic concept, rough guideline. and simple architecture about RFID privacy protection. Industry needs more structured framework and detailed systematic process to incorporate privacy issues into the RFID system. The purpose of this paper is to develop a framework and detailed process design of RFID privacy protection issues in retail industries. A framework is developed based on individual sensitivity concept, RFID contents, and interface with EPC global standard. Case study is applied to validate the framework and it turns out to be useful. It is expected that the proposed framework and process design would provide more systematic guide lines to solving RFID privacy problems.

• Structural Engineering and Mechanics
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• v.6 no.1
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• pp.17-30
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• 1998

The method of pairwise comparison inherently contains information of ambiguity, fuzziness and conflict in design goals for a multiobjective structural design. This paper applies the principle of paired comparison so that the vaguely formulated problem can be modified and a set of numerically acceptable weight would reflect the relatively important degree of multiple objectives. This paper also presents a fuzzy global criterion method ($FGCM_{\lambda}$) included fuzzy constraints that coupled with the objective weighting rank obtained from the modified pairwise comparisons for fuzzy multiobjective optimization problems. Descriptions in sequence of this combined method and problem solving experiences are given in the current article. Multiobjective design examples of truss and mechanical spring structures illustrate this optimization process containing the revising judgement techniques.