• Journal of the Korean Society for Precision Engineering
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• v.22 no.11 s.176
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• pp.59-63
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• 2005

Since human listening is very sensitive when the sound hit him, the subjective index of sound quality is required. Therefore, at each situation of sound evaluation its composed with the sound quality factor. But, when substituting the level of one frequency band we could not see the tendency of substitution at whole frequency band during the sound quality evaluation. In this study a design of experiment is used. The frequency domain is divided into an equally 12 parts and each level of domain whether is given increase or decrease due to the change of frequency band based on 'sharp' and 'annoy' of the sound quality is analyzed. By using the design of experiment the number of test is reduce very effectively by the number of experiment and each band the main effect will be as a solution. The case of sound quality for 'sharp' and 'annoy' at each band, the change of band (increase or decrease of sound pressure or keep maintain) which will be the most effects on the characteristics of sound quality can be identify and this will be able to us to select the objective frequency band. Through these obtained results the physical changes of level at arbitrary frequency domain sensitivity can be adapted.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.3
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• pp.9-18
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• 2008

The study was intended to suggest the design alternatives of rural village community center based on the design directions which were derived from the previous research, and to evaluate the alternatives by rural residents. The previous research was carried out to grasp the conditions and user's needs of rural village community center. The subjects were 100 residents who lived in rural area in Chonlabukdo. The interview was carried out using a questionnaire with model and isometrics of two alternatives, which showed floor plan and building shape. The subjects evaluated positively both of two alternatives, but slightly more preferred alternative | because of a spacious diningroom and an indoor toilet. The size of a livingroom and entrance, indoor toilet space/location, storage space and deck were significant elements in two alternatives according to t-test. They responded that both of indoor and outdoor toilet should be planned in rural village center. Also, each toilet and room for man and woman should be separated. Entrance space should be enough to take on/off their shoes in a sitting position and deck space was planned to intermediate between indoor and outdoor space.

• Journal of the Korean Society of Safety
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• v.24 no.1
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• pp.1-6
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• 2009

In machining of ceramic materials, they are very difficult-to cut materials because of there high strength and hardness. Machining of ceramics are characterized by cracking and brittle fracture. Generally, ceramics are machined using conventional method such as grinding and polishing. However these processes are generally costly and have low MRR(material removal rate). This paper focuses on machinability evaluation of machinable ceramics for products with CNC machining center. Thus, in this paper, experiment applying cutting parameters is performed based on experimental design method. A design and analysis of experiments is conducted to study the effects of these parameters on the surface roughness by using the S/N ratio, analysis of ANOVA, and F-test. And multiple linear regression analysis is applied to compare experimental with predicted data in consideration of surface roughness. Cutting parameters, namely, feed, cutting speed and depth of cut are used to accomplish purpose of this paper. Required experiments are performed, and the results are investigated.

• Progress in Superconductivity and Cryogenics
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• v.22 no.4
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• pp.57-61
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• 2020

Cooling by gas helium circulation can be used for various HTS (high temperature superconductor) magnets operating at 20~40 K, and a cryogenic blower is an essential device for circulating gas helium in the cooling system. The performance of the cryogenic blower is determined by various design parameters such as the impeller diameter, the blade number, the vane angle, the volute cross-sectional area, and the rotating speed. The trailing edge angle and the height of impeller vane are also key design factors in determining the blower performance. This study describes the design, fabrication and performance evaluation of cryogenic blower to produce a flow rate of 30 g/s at 5 bar, 35 K gas helium. The impeller shape is designed using a specific speed/specific diameter diagram and CFD analysis. After the fabrication of the cryogenic blower, a test equipment is also developed using a GM cryocooler. The measured flow rates and the pressure differences are compared with the design values at various rotating speeds and the results show a good agreement. Isentropic efficiency is also evaluated using the measured pressures and temperatures.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.6
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• pp.26-32
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• 2015

In this study, it is evaluated for fracture toughness to analyze crack resistance properties of particulate reinforced composite propellant. Fracture toughness test using WST specimen is conducted by temperature conditions from $50^{\circ}C$ to $-60^{\circ}C$. Evaluation method for fracture toughness calculated using an equation suggested by ASTM E399 with linear elastic fracture mechanics. From these result, splitting loads and stress intensity factors of propellant increase according to decrease of test temperature. Also, the strain fields of specimen surface using digital image correlation increase as temperature decreased from $50^{\circ}C$ to $-40^{\circ}C$, but it sharply decreases at $-60^{\circ}C$ because of brittle behavior.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.2
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• pp.15-30
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• 2007

The purpose of this study is to investigate the effect of makeup, clothing tone and clothing style on wearer's with same color coordination of lipstick and clothing. The experimental materials developed for this study were a set of stimulus and response scales (7-point scale semantic). The stimuli were 64 color pictures were manipulated by computer simulation. This experiment design was $2{\times}2{\times}4{\times}4$ factorial design. The stimuli were a set of eyeshadow color(brown), clothing style (formal style of Jacket / skirt and casual style of cardigan / pants), lipstick and clothing color (red and orange), lipstick tone(vivid, light, dull and dark), clothing tone(vivid, light, dull and dark). The subjects of this research were 384 female undergraduates living in Gyeongsangnam-do. The investigation was carried out at a lecture hall at the time between 10 a.m. and 3 p.m. in May 2006. The data were analyzed using SPSS program. Factor analysis, 4-way ANOVA, t-test, and Duncan test were used as analysis methods. Image factors according to variation of clothing style, clothing color, and makeup color are composed of 4 different dimensions (visibility, attractiveness, tenderness, and stability). In dimension of the visibility, the image was perceived to be glowing and luxurious regardless of lipstick tone and lipstick color in the case of the vivid tone clothing. According to the variation of clothing style, clothing color and tone, makeup color composed of eyeshadow color, lipstick color and tone, it was investigated that the images for a clothing wearer were expressed diversely, were shown differently in image dimensions, and could be produced to different images. The analysis data for images according to the combination of makeup and clothing color, tone, and style thus provide basic material for image consulting or color coordination.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.41-48
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• 2011

Warm-Mix Asphalt(WMA) mixtures, which meet environmental protection and have high energy efficiency, are emerging as an alternative to hot-mix asphalt mixtures. The objective of this study is to evaluate WMA made with Aspha-min in the laboratory and to compare the design results accomplished by new Mechanistic-Empirical Pavement Design Guide(MEPDG) with control mixture. An asphalt mixture with a nominal maximum size of 12.5mm and PG64-28 binder was used. Resilient modulus tests for a control mixture and WMA with 0.3% and 0.5% of Aspha-min were conducted. The results obtained by MEPDG after inputting the test output into the design indicated that the predicted rut depth of WMA using Aspha-min was much lower than that of control mixture, and showed that WMA was more resistant to rutting than control mixture.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.1045-1050
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• 2010

Fatigue analysis and lifetime evaluation are very important in design procedure for assuring the safety and reliability of rubber components for mechanical systems. Till recently, the technology for the design, analysis, and evaluation of rubber products was required to manufacture rubber products with high quality, fidelity, and reliability. However, in the rubber-manufacturing companies in Korea, the processes of compound mixing, manufacturing of rubber products, and improvement of rubber properties are based on the trial-and-error method and experience. The objectives of this study are to establish methods for testing rubber materials, to develop a database of the properties of rubber materials, to evaluate the performance of rubber components, and to develop a system for predicting fatigue life. A method to predict fatigue-life of rubber components was proposed; in this method, the finite-element analysis and fatigue damage parameter as determined from a fatigue test are incorporated.

• Korean Journal of Human Ecology
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• v.7 no.3
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• pp.5-13
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• 2004

This study was performed to investigate the characteristics of denim pants preferred by Korean women in their 20's through the analysis of the sensory test(appearance) and garment space length. Four kinds of ready-made denim pants of national and licensed brand on sale in Korea were used as the experimental garment. The results were as follows: 1. The significant difference among brands were found in the appropriateness of ease in the part of waist belt(front), knee (front), ankle(back) and the total silhouette. 2. In the analysis of garment space length. the significant difference among brands was shown in waist belt part $(FL60^{\circ})$, hip $(FL0^{\circ},\;FL30^{\circ})$, crotch(SRR) and knee(BR60^{\circ}). However, total average was not significant difference. 3. According to analysis of pattern size, the brand N was out of balance in crotch depth and girth. by which it can be said that N got the lowest score in sensory test (appearance). On the other hand, Brand GU was large in circumference with short crotch length. 4. Therefore, the most preferred denim pants pattern of Korean women in their 20's was fit in waist belt. hip. crotch circumference and a little bit tight in crotch depth and length. As the design was limited as straight style. more design and brands must be included for future study.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.3
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• pp.424-435
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• 2022

Aesthetic impression, structural stability, functionality during exercise, freedom of movement and physiological suitability should be considered when developing aquarobic wear for middle-aged women. We conducted a visual evaluation of the commercial aquarobic wear of the five brands (ARENA, TURN, RALLY, RENOMA and ELLE) with the highest market share and selected three items: one-piece type (OPT); two-piece type (TPT) and whole-body type (WBT). These are the most worn types of aquarobic wear for each brand. The G4 showed the best results in appearance evaluation of the shoulder strap width, front neckline, armhole line, side hip line and short pants length in the OPT category. The TPT had better ratings as the shoulder strap was located in the center of the shoulder, and the front and the back necklines were not too deep. The five items of WBT clothing received similar ratings for each element, so it is considered that the advantages are evenly distributed. No single design was a clear favorite. Based on the above results, continuous research on the development of aquarobic wear that is more suitable and preferable for middle-aged women should be conducted.