• International Journal of Highway Engineering
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• v.5 no.1 s.15
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• pp.1-10
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• 2003

The objective of pavement design, just as with the design of other structures, is to obtain the most economical designs at specified levels of reliability. Methods that yield designs with different levels of reliability are undesirable, and over the course of time design approaches in the U.S. and Europe have converged toward the Load and Resistance Factor Design (LRFD) format in order to assure uniform reliability. At present the LRFD format has been implemented in concrete, steel, wood and bridge design specifications. In this paper, reliability theories are used to illustrate the development of an LRFD format for Mechanistic-Empirical (M-E) design of flexible pavements as an alternative of its reliability module. It is shown in this paper that ten candidate pavement sections designed with a reliability level using the AASHTO design guide (1986) do not have uniform structural reliability in terms of pavement mechanistic distress such as fatigue cracking and the uniform reliability can be achieved by using the LRFD format.

• Journal of the Korean Society of Costume
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• v.44
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• pp.19-36
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• 1999

A military uniform has two basic characters. One is functionality for field warfare and the other is decorativeness to express dignity and power to maintain systematic organization. For these purposes, the military uniform is maximizing its effects on functionality and decorativeness on each aspects of material, color, dignity, item, military ornaments and accessories. During wartime, the military uniform improved its functionality and gave much influence on normal clothing at the same time either directly or indirectly. Military look became more diverse. In a mood for the end of century and inflated material civilization, and with nostalgia for the fast, mixed styles of fast, presents and future have come out in variety. In Street Fashion, there are many alternative trends to meet diverse desires of teenagers, and the military look has been steadily favored. The functionality and the decorativeness of military look would have met fashion sense and taste of younger generations pretty well. First, teenagers are active, and the practical materials and functional designs of military style applied to their clothes. Second, they prefer challenging and creative styles, and the decorative elements of military clothing for the colors, patterns, accessories have been applied to they clothing. We may need to understand their culture and emotion more closely and help them enjoy sound and beautiful clothing culture. The military uniform adapted itself to natural and social environments and has been developed and improved, which made that possible.

• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.138-145
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• 2017

The problem of non-uniform inflow exists in many practical engineering applications, such as the elbow suction pipe of waterjet pump and, the channel head of steam generator which is directly connect with reactor coolant pump. Generally, pumps are identical designs and are selected based on performance under uniform inflow with the straight pipe, but actually non-uniform suction flow is induced by upstream equipment. In this paper, CFD approach was employed to analyze unsteady hydrodynamic characteristics of reactor coolant pumps with different inflows. The Reynolds-averaged Naiver-Stokes equations with the $k-{\varepsilon}$ turbulence model were solved by the computational fluid dynamics software CFX to conduct the steady and unsteady numerical simulation. The numerical results of the straight pipe and channel head were validated with experimental data for the heads at different flow coefficients. In the nominal flow rate, the head of the pump with the channel head decreases by 1.19% when compared to the straight pipe. The complicated structure of channel head induces the inlet flow non-uniform. The non-uniformity of the inflow induces the difference of vorticity distribution at the outlet of the pump. The variation law of blade to blade velocity at different flow rate and the difference of blade to blade velocity with different inflow are researched. The effects of non-uniform inflow on radial forces are absolutely different from the uniform inflow. For the radial forces at the frequency $f_R$, the corresponding amplitude of channel head are higher than the straight pipe at $1.0{\Phi}_d$ and $1.2{\Phi}_d$ flow rates, and the corresponding amplitude of channel head are lower than the straight pipe at $0.8{\Phi}_d$ flow rates.

• Earthquakes and Structures
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• v.7 no.6
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• pp.1025-1044
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• 2014

In this paper, a systematic technique is proposed for the optimal placement and design of nonlinear dampers for building structures. The concept of Output Frequency Response Function (OFRF) is applied to analytically represent the output frequency response of a building frame where nonlinear viscous dampers are fitted for suppression of vibration during earthquakes. An effective algorithm is derived using the analytical representation to optimally determine the locations and parameters of the nonlinear dampers. Various numerical examples are provided to verify the effectiveness of the optimal designs. A comparison of the vibration suppression performance with that of the frame structure under a random or uniform damping allocation is also made to demonstrate the advantages of the new designs over traditional solutions.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.86-93
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• 2003

These days, automobile industry pays considerable attention to child occupant safety. As the US adopted requirements for universal and uniform anchor systems for child restraints, manufacturers for child seats put an enormous effort to improve the protective properties of Child Restraint System (CRS). Various standards have been studied and announced by different countries. The anchorage system is the most important in the CRS and the rules of universal anchor are to provide devices which are independent of safety belts. A new concept called International Standard Organization Fixture (ISOFIX) has been announced. It suggests some designs for the CRS. In this study, the suggested designs are evaluated with domestic products. Tests are performed and the results are incorporated into a finite element modeling process. As the finite element model is established, various numerical tests are conducted and the numerical results are discussed. A commercial software system is utilized for the nonlinear finite element analysis.

• Geomechanics and Engineering
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• v.38 no.2
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• pp.179-189
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• 2024

This paper presents a geomechanical framework for designing and optimizing layout patterns of cutterheads for rock Tunnel Boring Machines (TBMs), aiming to enhance their engineering performance. By examining the forces and moments exerted by rock, the study addresses geometric constraints associated with cutter boxes in key regions of the cutterhead, including the center, face, and gage areas, as well as the three-dimensional effects of cutterhead curvature on the geometric constraints of the back of the cutter boxes in the gage area. Novel formulas are proposed for determining the center points of cutter boxes and calculating both the minimum angular spacing and distance spacing between consecutive cutter boxes along a spiral path. The paper outlines an optimized layout design process for four cutterhead configurations: random, random paired, radial, and double spiral designs. Examples are provided to illustrate the results of applying these designs. The findings underscore the efficacy of the proposed methods in achieving a uniform and symmetrical distribution of cutters and buckets on the cutterhead surface. This approach effectively eliminates boundary overlap and minimizes unbalanced forces and moments. From a geomechanical standpoint, this framework offers a robust strategy for enhancing the performance and reliability of TBM cutterheads in rock tunneling operations.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.4
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• pp.776-787
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• 2020

This study investigated physiological and subjective responses to different types of firefighter station uniforms made with various designs and materials. Six healthy males participated in this study that consisted of 20 min of rest, 30 min of treadmill exercise, and 30 min of recovery in a hot and humid environment (34℃ and 65%RH). The experimental clothing conditions were as follows. 1) a fitted T-shirt and trouser made of 100% polyester (FC-Uniform), and 2) flame retardant T-shirts made of acrylic and cotton as well as trousers with aramid and polyester, designed for overfitting (Control). There were no significant differences in the body temperature, and sweat rate between the two conditions; however, the heart rate with the FC-Uniform was significantly lower than Control (p=.025). The clothing microclimate temperature at the chest of the FC-Uniform was significantly lower than the Control (p=.037), and a difference of 1℃ was maintained until the recovery was complete. There were no significant differences in the subjective responses; however, participants experienced a humidity sensation faster with FC-Uniform in the recovery phase. The results indicate that changes in the design and material of firefighter station uniforms may have a positive influence on reducing the thermal stress of firefighters.

• The Research Journal of the Costume Culture
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• v.14 no.1
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• pp.27-39
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• 2006

The field of textiles and clothing is intimately involved in the business as a practical study. Many researchers consider how apply the theory to the business. Therefore, the study explores a process which builds an efficient relationship of industry-university focused on the example applied to an industry-university project of uniform design. The development process of the studyis composed of 4 levels: research and analysis, design development, production of samples, and manufacturing. In the process of research and analysis, it found out preference of design elements. These elements were reflected in design development to satisfy employee of wearing uniform. In the level of design development, 20 designs were deployed to use CAD system. Five deigns of them were produced to samples in 3 stages. Finally, to manufacturing was in charge of cooperative enterprises with clothing production equipment and university played a role of inspector. From theses research results, it has known that the field of uniform business is suitable for industry-university project because an enterprise with an order can get advice about clothing, a manufacturing company is able to complement a weaknessin the design, and university can have a chance applied the theory to the business. After this, the study will make a contribution to setting the direction of business to industry-university project.

• Fashion & Textile Research Journal
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• v.8 no.1
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• pp.25-33
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• 2006

As the cultures of the world are getting diverse and plural, many trials to find their own unique culture of their own national and racial characteristics are made where fashion and traditional culture is used as good materials; in Korea, this trend is also studied by many authors. To achieve this goal, this study recognized the importance of tourism industry by inviting hosting of international event like '2005 APEC Summit Conference and Economical Ministers' Conference', and invented a uniform design that can make identification in the world market including Korea 'Gust' and 'Emotion' in developing uniforms for employees of regular traditional restaurant or hotels that contribute to tourism industry. As a material of this study from this perspective, Soo Bok pattern among many other Korean traditional patterns were chosen, and used them to design uniforms by applying diverse expressions methods through modernization task. This study tried to suggest ideas in creating new designs with a modeling sense of our people, by emphasizing on tradition motive through analysis of conditions and problem regarding the current uniforms worn in traditional restaurants. The development of uniform that modernly reinterprets traditional patterns and design that uses tradition on modern design shows endless possibility of development of our uniform, and even shows the possibility of mixture between tradition and modernity. By applying traditional beauty not only in traditional restaurants but also in many places and businesses that foreigners frequently visit can allow to spread the excellency our culture; and the Korean uniform can be successful in the international market as Korean will have pride in our tradition by wearing this new uniform.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.641-646
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• 2015

In this paper, a zinc electrowinning cell is fully optimized to achieve a uniform current distribution at electrode surfaces. To effectively deal with an electromagnetically coupled problem with multi-dimensional design variables, a sampling-based sensitivity approach is combined with a highly tuned multiphysics simulation model. The model involves the interrelation between electrochemical reactions and electromagnetic phenomena so as to predict accurate current distributions in the electrowinning cell. In the sampling-based sensitivity approach, Kriging-based surrogate models are generated in a local window, and accordingly their sensitivity values are extracted. Such unique design strategy facilitates optimizing very complicated multiphysics and multi-dimensional design problems. Finally, ten design variables deciding the electrolytic cell structure are optimized, and then the uniformity of current distribution in the optimized cell is examined through the comparison with existing cell designs.