• 한국항공운항학회지
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• 제28권1호
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• pp.83-89
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• 2020

Personal air vehicle (PAV) is considered by aviation engineers as a solution to provide fast urban mobility. The purpose of designing a optionally piloted PAV (OPPAV) is to provide an individual air vehicle. The airframe structure is designed with high strength carbon fiber composite to reduce the aircraft weight. This paper presents an overview of sizing process for OPPAV at the conceptual design level. It consists of load analysis, structural sizing and development of efficient design allowable values for composite material. The weight is estimated based on sizing process, including strength and stiffness requirements. The objective of this study is to present a overview of structural sizing procedure and fast tool for preliminary design phases.

• 대한인간공학회지
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• 제23권3호
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• pp.25-38
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• 2004

Selection of a key dimension (s) by considering the characteristics of hand dimensions is needed to design gloves and construct a sound sizing system for gloves The present study identified key dimensions of glove design by analyzing the relationships between hand dimensions and demonstrated the construction process of a glove sizing system. By conducting correlation and regression analyses on 70 hand dimensions including 3 key dimension candidates (hand length; hand circumference; hand breadth) with the 1988 US Army data, hand length and hand circumference were selected as key dimensions for glove design. Glove sizing systems were constructed for males and females by applying the selected key dimensions, 0.5 inch of sizing intervals, and 2％ of presence rate criterion to the US Army data. This study suggests that glove sizing systems for males and females be very different from each other and a glove sizing system for males include more sizes than that for females.

• 한국연소학회지
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• 제20권3호
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• pp.27-34
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• 2015

The objective of the current study is to introduce detailed process for a preliminary combustor design, and to develop a computer code for it. The program includes various empirical and semi-empirical methodologies for diffuser deign, combustor sizing, air distribution, and sub-component design such as primary and secondary zones. Using the developed program, the combustor sizing results are shown from an assumption of simple annual combustor cycle analysis. Two options are employed, 1) pressure loss approach, and 2) velocity assumption approach. Design results show that there are no significant differences in combustor sizing between two design options. Further code improvement is required for performance and emission evaluations of the designed combustor.

• 한국해양공학회지
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• 제27권5호
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• pp.36-42
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• 2013

We present the optimum design for the cross-sectional(sizing) and shape optimization of truss structures with natural frequency constraints. The optimum design method used in this paper employs continuous design variables and the Harmony Search Algorithm(HSA). HSA is a meta-heuristic search method for global optimization problems. In this paper, HSA uses the method of random number selection in an update process, along with penalty parameters, to construct the initial harmony memory in order to improve the fitness in the initial and update processes. In examples, 10-bar and 72-bar trusses are optimized for sizing, and 37-bar bridge type truss and 52-bar(like dome) for sizing and shape. Four typical truss optimization examples are employed to demonstrate the availability of HSA for finding the minimum weight optimum truss with multiple natural frequency constraints.

• 소성∙가공
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• 제18권1호
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• pp.52-58
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• 2009

Generally, a vertical rolling process is used to achieve extensive width reduction in hot strip mill. However, it is impossible to avoid the defects such as dog-bone and edge-seam defect. The sizing press process has been developed in response to the defects mentioned above. Especially, this study is carried out to investigate the deformation of slab by two-step sizing press. The deformation behavior of slab in the sizing press process is more favorable than that in conventional vertical rolling edger. The FE-simulation is applied to predict the deformation behavior of the slab. In this paper, the several causes of the asymmetrical deformation are mentioned for the purpose of understanding of the anvil shape. Load, dog-bone and edge-seam defect are discussed in width sizing process considering the anvil shape. And to reduce the problems generated at rougher mill just after sizing press, these are studied in this paper. The deformation behavior of slabs and optimum anvil shape are obtained by rigid-plastic finite element analyses and neural network.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2561-2567
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• 2018

The extension of DC battery backup time in the DC power supply system of nuclear power plants (NPPs) remains a challenge. The lead-acid battery is the most popular at present. And it is generally the most popular energy storage device. However, extension of backup time requires too much space. The lithium-ion battery has high energy density and advanced gravimetric and volumetric properties. The aim of this paper is development of the sizing formula of stationary lithium-ion batteries. The ongoing research activities and related industrial standards for stationary lithium-ion batteries are reviewed. Then, the lithium-ion battery sizing calculation formular is proposed for the establishment of industrial design standard which is essential for the design of stationary batteries of nuclear power plants. An example of calculating the lithium-ion battery capacity for a medium voltage UPS is presented.

• 한국연소학회지
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• 제18권3호
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• pp.54-60
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• 2013

This paper shows a general development process for aircraft gas turbine combustors. As a first step for developing the preliminary combustor design program, several combustor sizing methodologies using reference area concepts are reviewed. There are three ways to determine the reference area; 1) combustion efficiency approach, 2) pressure loss approach, 3) velocity assumption approach. The current study shows the comparisons of the calculated results of combustor reference values from the pressure loss and velocity assumption approaches. Further works are required to add iterative steps in the program using more reasonable values of pressure loss and velocities, and to evaluate the sizing results using data for actual combustor performance and sizes.

• 복식문화연구
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• 제14권1호
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• pp.48-63
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• 2006

The purpose of this study was to provide information on how to improve both the satisfaction and the current sizing system for the school uniform focused on middle and high school boys' students. In order to collect the data, a questionnaire was administered to 451 middle and high school boy students. 228 middle school boys' and 223 high school boys' data were analyzed using the SPSS Win. 10.0 program. The results of this study were as follows : 1. For the satisfaction of their school uniform, there were statistical differences in mean of the group by the academic year in the jacket(color, textile, design, activity), shirt(color, design, activity), and pants(color, design, activity) in the case of middle school boys'. On the other hand, high school boys' evaluation of school uniform was significantly different in jacket(color), shirt(color, textile, design, activity), pants(design), and tie(color, textile, design) by the academic year. 2. For the evaluation of sizing fitness, the length of jacket and the breadth of sleeve in jacket, and the width of sleeve in blouse, the length of pants, and the width of pants were statistical differences in mean of the group in middle school boys' by the grade whereas there was no significant difference in high school students by the grade. 3. It was shown that more getting school uniform repaired after the point of purchase in both middle school and high school students was higher.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 추계학술발표회논문집(1)
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• pp.558-563
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• 1997

A thermal sizing code, named as HSGSA (Helical coil Steam Generator Sizing Analyzer), for a sodium heated helical coil steam generator is developed for KALIMER (Korea Advanced LIquid MEtal Reactor) design. The theoretical modeling of the shell and tube sides is described and relevant correlations are presented. For assessment of HSGSA, a reference plant design case is compared to the calculational outputs from HSGSA simulation.

• 복식
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• 제64권6호
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• pp.33-46
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• 2014

The purpose of this study is to present basic data for the standardization of the sizing system for children's wear by investigating the current production and sizing system of Korean children's wear brands. The result of conducting a survey of 20 brands show the following: first, regarding the age bracket of Korean children's wear, it ranged from 3~15 years old. Most of the brands divided up the sizes into 4 or 5 different groups. Second, the utilization of a bodice basic pattern was low during the manufacturing of a pattern, and the basic pattern had been used for the item. Third, the designation of garment sizes were done using height or height-chest measurement or height-waist measurement. Fourth, the brands used the smallest size as the basic size in most cases. Most of the brands had similar deviations for any grading deviations. In conclusion, it appears necessary to restructure the unity of size designation and the sizing system in order to establish the sizing system of children's wear, which features diverse age brackets and various body types.