• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.471-477
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• 2014

The novel permanent magnetic actuator (PMA) and its optimal design method were proposed in this paper. The proposed PMA is referred to as the separated permanent magnetic actuator (SPMA) and significantly superior in terms of its cost and performance level over a conventional PMA. The proposed optimal design method uses the evolutionary strategy algorithm (ESA), the kriging meta-model (KMM), and the multi-step optimization. The KMM can compensate the slow convergence of the ESA. The proposed multi-step optimization process, which separates the independent variables, can decrease time and increase the reliability for the optimal design result. Briefly, the optimization time and the poor reliability of the optimum are mitigated by the proposed optimization method.

• Journal of the Korean Society of Costume
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• v.60 no.8
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• pp.151-167
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• 2010

This research is to analyze ethics in fashion design for more valuable and sustainable human life against the increasing alienation of the human being, the global ecological crisis resulted from contemporary consumption society. I expect that it can be helpful to plan ethical fashion design practice more effectively. For this, the documentary study and practical case study have been executed. The results are as follows. The ethics in design can be defined as the responsibility to reform the social, environmental problem of consumptive design, to sustain together without human alienation, environment disruption and to do social good for total human being ultimately. The ethical design practice means to suggest solutions to problems of human rights and environment and to act willingly. Based on this, ethical fashion design appeared as responsible design solution which has two directions. One is the fashion design for coexistence and sharing, including the design for all which considers even underprivileged minority, the design to promote public issues as well as to donate some profits. The other is the eco fashion design for sustainable environment, including eco-friendly design which is reductive and slow in whole design process, the design to inform the seriousness of environmental crisis as well as to donate some profits. The last one of the most important ethical responsibility as fashion designer is to abide by vocational ethics, that is, the prohibition of design piracy.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.3
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• pp.370-379
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• 2015

Handling constantly evolving configurations of aircraft can be inefficient and frustrating to design engineers, especially true in the early design phase when many design parameters are changeable throughout trade-off studies. In this paper, a physics-based design framework using parametric modeling is introduced, which is designated as DIAMOND/AIRCRAFT and developed for structural design of transport aircraft in the conceptual and preliminary design phase. DIAMOND/AIRCRAFT can relieve the burden of labor-intensive and time-consuming configuration changes with powerful parametric modeling techniques that can manipulate ever-changing geometric parameters for external layout of design alternatives. Furthermore, the design framework is capable of generating FE model in an automated fashion based on the internal structural layout, basically a set of design parameters describing the structural members in terms of their physical properties such as location, spacing and quantities. The design framework performs structural sizing using the FE model including both primary and secondary structural levels. This physics-based approach improves the accuracy of weight estimation significantly as compared with empirical methods. In this study, combining a physics-based model with parameter modeling techniques delivers a high-fidelity design framework, remarkably expediting otherwise slow and tedious design process of the early design phase.

• Elastomers and Composites
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• v.46 no.4
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• pp.335-342
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• 2011

The virgin and recycled polyethylene composites with various ratio of fly ash were manufactured by using a fully intermeshing co-rotating twin screw extruder for the reuse of fly ash from power plant and post-consumed polyethylene. Fly ash were blended with virgin HDPE and recycled polyethylene at the weight fraction of 0 to 40 wt.%. Mechanical properties such as yield strength, abrasion resistance, and slow crack resistance were measured with ISO and ASTM standards. The experimental results for the various composites showed that the elongation at break and the yield stress of the composites decreased with increasing fly ash contents. Generally, the abrasion resistance of PEs decreased with increasing sandpaper grits but the abrasion resistance of the composites increased with fly ash content at finer abrasive surface. The slow crack growth resistance of virgin HDPE, recycled JRPE and the JRPE composite showed higher slow crack growth resistance up to 50% of load at notch depth of 20% and 30%, but KRPE and the KRPE composite showed much lower resistance than virgin HDPE, JRPE and the JRPE composite. Time to break, measured with NCLS test method, of all PEs and the composites satisfies the regulation of Korean Industrial Specification for sewer pipe and support application.

• Smart Structures and Systems
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• v.16 no.6
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• pp.1147-1167
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• 2015

Wireless smart sensors, which have become popular for monitoring applications, are an attractive option for implementing structural control systems, due to their onboard sensing, processing, and communication capabilities. However, wireless smart sensors pose inherent challenges for control, including delays from communication, acquisition hardware, and processing time. Previous research in wireless control, which focused on semi-active systems, has found that sampling rate along with time delays can significantly impact control performance. However, because semi-active systems are guaranteed stable, these issues are typically neglected in the control design. This work achieves active control with smart sensors in an experimental setting. Because active systems are not inherently stable, all the elements of the control loop must be addressed, including data acquisition hardware, processing performance, and control design at slow sampling rates. The sensing hardware is shown to have a significant impact on the control design and performance. Ultimately, the smart sensor active control system achieves comparable performance to the traditional tethered system.

• Journal of computational fluids engineering
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• v.6 no.3
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• pp.10-18
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• 2001

Genetic Algorithm(GA) is applied to aerodynamic shape optimization and demonstrated its merits in global searching ability and the independency of differentiability. However, applications of GA are limited due to slow convergence rate, premature termination, and high computing costs. The present aerodynamic designs such as wing shape optimizations using GA have seldom been applied because of high computing costs. This paper has two objects; improvement of the efficiency of GA and application of GA into aerodynamic shape optimization for 2D and 3D wings. The study indicates that GA can be applied to aerodynamic design and its performance is comparable to traditional design methods.

• Journal of Korea Multimedia Society
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• v.22 no.8
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• pp.897-912
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• 2019

The growth of domestic fashion industry market went sluggish affected by long-term slow growth and shrinking consumer sentiment since 2012, and the entire market has shown a slight growth since 2017. Yet only some conglomerates or global businesses experience this growth. Small and medium-sized fashion companies or rising fashion designers in South Korea, face real limitations and problems poor capital, lack of professional workforce, experience, information and educational opportunity as well as difficulty of acquiring distribution network, which lead to further polarization between conglomerates and small businesses. Thus, this study proposed mobile virtual viewer system-based collaborative application prototype capable of overcoming limitations and problems drawn by analyzing business environment of domestic brands launched by rising fashion designers. Especially, through applied template-based 3D virtual fashion design technology and performing the entire process in the virtual reality beyond spatial and temporal restraints, it is assumed that more effective and efficient outcomes can be obtained compared to the previous method.

• The Research Journal of the Costume Culture
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• v.15 no.6
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• pp.952-964
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• 2007

This study is about the design for environment which is central social interest in recent days. This study focused on both experimental designs which convey meanings and practical designs which can be produced within the fashion industry and then influence on the wide range of consumer, human and surrounding environment. The purposes of this study are to categorize national and global fashion designs for environment, to analyze data based on the fashion pipeline from planning to discard, to suggest systematic actions, and to establish fashion design for environment model. Through these processes, this study helps in making fashion designs for environment more understandable, and demonstrates one future direction for using environment as fashion industry's innovative strategy. This study attempts to create business and at the same time suggests design actions based on social belief. The results of this study are following. Fashion designs for environment were categorized by organic fabric, new-to-the-world fabric, reduce, multi-function, reproduce, order-made, recycle, and reuse. The results show that fashion designs for environment have been implemented throughout the fashion pipeline, and applied the concepts of design for environment including green, sustainable slow, and natural design principles. Furthermore, labelling and service from supply side, green purchasing from demand side, and integration from both sides are suggested as company's and society's systematic actions.

• International Journal of Control, Automation, and Systems
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• v.6 no.5
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• pp.677-688
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• 2008

In this paper, the general problem of impedance control for a robotic manipulator with a moving flexible base is addressed. Impedance control imposes a relation between force and displacement at the contact point with the environment. The concept of impedance control of flexible base mobile manipulator is rather new and is being considered for first time using singular perturbation and new sliding mode control methods by authors. Initially slow and fast dynamics of robot are decoupled using singular perturbation method. Slow dynamics represents the dynamics of the manipulator with rigid base. Fast dynamics is the equivalent effect of the flexibility in the base. Then, using sliding mode control method, an impedance control law is derived for the slow dynamics. The asymptotic stability of the overall system is guaranteed using a combined control law comprising the impedance control law and a feedback control law for the fast dynamics. As first time, base flexibility was analyzed accurately in this paper for flexible base moving manipulator (FBMM). General dynamic decoupling, whole system stability guarantee and new composed robust control method were proposed. This proposed Sliding Mode Impedance Control Method (SMIC) was simulated for two FBMM models. First model is a simple FBMM composed of a 2 DOFs planar manipulator and a single DOF moving base with flexibility in between. Second FBMM model is a complete advanced 10 DOF FBMM composed of a 4 DOF manipulator and a 6 DOF moving base with flexibility. This controller provides desired position/force control accurately with satisfactory damped vibrations especially at the point of contact. This is the first time that SMIC was addressed for FBMM.

• Journal of the Korean Geotechnical Society
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• v.32 no.8
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• pp.47-59
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• 2016

Rocking behavior of shallow foundation reduces the superstructure load during earthquake. However, because of deficiency of understanding of rocking mechanism and soil permanent deformation, it has not been applied to real construction. In this study, slow cyclic tests were conducted for embedded shallow foundations with various slenderness ratio via centrifuge tests. From the variation of earth pressure 'soil rounding surface' phenomenon which makes maximum overturning moment equal to ultimate moment capacity was observed. Rocking and sliding behavior mechanism was evaluated. Also, nonlinear behavior and energy dissipation increase as rotation angle increases. And ultimate moment capacity of embedded foundation is larger than that of surface foundation. Finally, adequate ultimate moment capacity can be suggested for seismic design through this study.