• 한국의류학회지
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• 제17권1호
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• pp.19-35
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• 1993

This study was designed to devise work wear for plastic house worker. It was carried out (1) research on the clothing actual condition through interviewings with plastic house worker and observations, (2) thermal manikin test to measure thermal resistance of experimental clothes and (3) clothing comparing test in the laboratory and in the plastic house. In the laboratory experiment, it was choosen general type (A) and new devised types (B, C) made of microporous fabric for experimental clothes. Experimental clothes were made of 6 combinations including 3 type work wears (A, B, C) and 2 type underwears (1, 2). In the plastic house experiment, it was choosen general types of A (without rest place) and B (with rest place), and devised type C (with rest place), which was appeared good effect in the laboratory experiment. The results were as followings. 1. Work environment of the plastic house in summer and winter was very different from the outer environment. Work motion in the plastic house was burden to the plastic house workers. 2. Plastic house workers had on the general type's work wear. 3. As a result of thermal manikin test, thermal resistance was appeared B1>B2>C2>C1>A1>A2 in orders. 4. In the laboratory experiment, experimental clothes A was appeared smaller burden than B, C. Effect of mesh underwear was not appeared in this study condition. In subjective sensation, experimental clothes C was lower vote than A. Therefore experimental clothes C was superior to A in subjective wearing sensation. 5. In the plastic house experiment, the experimental conditions with rest place were appeared smaller burden than without rest place. General type B was appeared more positive physiological reactions than devised type C but significances between two types was not appeared.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.235-239
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• 2002

The objective of the experiment is to investigate the effect of microstructures of gray cast iron oil wear characteristics of automotive disc brakes. Six different gray cast iron rotors were manufactured by changing carbon equivalent and cooling rate. The change of DTV (disc thickness variation) before and after wear tests was measured to examine the wear properties according to the microstructures of gray iron discs since the DTV generation is caused by the circumferential uneven wear. Experimental results showed that the morphology of graphite flake and hardness in gray cast iron were crucially associated with the change of DTV. In particular, the DTV changes of rotor decrease when the length and area fraction of graphite flake in brake rotors increase and hardness of brake discs reduces.

• 대한인간공학회지
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• 제17권1호
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• pp.115-123
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• 1998

We study the ski wear which are compared at the materials and the designes and their human physiological and phychological response during exercise in a cold and air-conditioned enviroments. Five men exercises in the experiment room with four types of ski-wears : two of one-piece and two of two-piece : two of special material and two of a normal material, respectively. We keep the environment at $-5^{\circ}C$ and speed of 3.6 mile/hr during the measurement of 13 points, which is a mean model of the Muju ski-resort at January 1996. We conclude the followings : 1. The ski-wear with special materials have higher than the normal type at mean skin temperature and rectal temperature. 2. Changes of temperature withing the clothes during the exercise is small, but the humidity within the clothes abruptly increases because of the weight loss. 3. Type A ski-wear with the special material has $295.5g/m^2hr$ weight loss, which is higher, and type D ski-wear is smaller 4. The special material shows comfortable in the thermal sensation. 5. In the design aspect of the ski-wears, the two-piece type ski-wear shows higher skin temperature and temperature & humidity within the clothes than the one-piece type due to the effect of the multiplicity.

• 한국생활과학회지
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• 제12권2호
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• pp.253-263
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• 2003

The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.

• 한국컴퓨터정보학회논문지
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• 제22권5호
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• pp.1-9
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• 2017

Recently, flash memory has been in a great demand from embedded system sectors for storage devices. However, program/erase (P/E) cycles per block are limited on flash memory. For the limited number of P/E cycles, many wear leveling techniques are studied. They prolonged the life time of flash memory using information tables. As one of the techniques, block erase table (BET) method using a bit array table was studied for embedded devices. However, it has a disadvantage in that performance of wear leveling is sharply low, when the consumption of memory is reduced. To solve this problem, we propose a novel wear leveling technique using Sampling-based Block Erase Table (SBET). SBET relates one bit of the bit array table to each block by using exclusive OR operation with round robin function. Accordingly, SBET enhances accuracy of cold block information and can prevent to decrease the performance of wear leveling. In our experiment, SBET prolongs life time of flash memory by up to 88%, compared with previous techniques which use a bit array table.

• Tribology and Lubricants
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• 제38권4호
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• pp.128-135
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• 2022

In the product development process, the reliability of the product can be secured through durability tests. However, since the durability test method is expensive and time consuming, a method to save time and money by utilizing virtual product development (VPD) is required. However, research on the accuracy of the results of virtual product development is required. In this paper, an accelerated durability test was designed and conducted using a planetary gear decelerator. And an analysis model under the same conditions was created and simulated. To correlate the results of the experiment with the results of the analytical model, created a model that can discriminate the wear region using one of the data mining methods, the k-means algorithm method and HSV (Hue, Saturation, Value). The wear area is compared by counting the number of pixels defined as wear through a discrimination model. A similar ratio was calculated by comparing the pixel ratio of the area determined as wear in the entire area. It showed a similar ratio of about 70%, and it is necessary to improve the discrimination method.

• 패션비즈니스
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• 제25권2호
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• pp.127-142
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• 2021

This study aims to organize the prototype design method of compression wear for women professional soccer players. Despite the excellent performance of female soccer players in world competition, most functional wear has been developed mainly for men, so professional female athletes have fewer choices. Soccer is a sport requiring core and lower body muscle strength, and muscular endurance for long periods of playing or walking on the field. Female soccer players did not differ much in upper body compared to other women, but their lower body had a smaller hip circumference than waist circumference and a larger thigh circumference, requiring compilation considering the physical characteristics and movement of athletes. Female soccer players wear sports bras while playing but regular bras and compression wear during normal exercise because they sweat on under their breast, which irritates sensitive skin. For core muscles in the upper body and to support for thigh and hip muscles in the lower body, the uniform in this study was designed by reducing the body size of a professional female soccer player in her 20s and the actual measurements of commercial compilation software to 81% of the chest circumference, 95% of the waist circumference, and 78% of the hip circumference. The design experiment in this study was a simple exercise and did not produce produce results for long-term exercise and performance improvement, but can be used to design a composition pattern system for other professional female athletes.

• 대한소아치과학회지
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• 제51권1호
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• pp.22-31
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• 2024

The objective of this study was to assess the wear resistance of tooth-colored materials used in crown restoration for primary molars with a chewing simulator. In this study, four groups-three experimental groups and one control group-were included. They consisted of three-dimensional (3D) printed resin crowns (NextDent and Graphy), milled nano-hybrid ceramic crowns (MAZIC Duro), and prefabricated zirconia crowns (NuSmile). Twelve mandibular second molar specimens were prepared from each group. In the wear experiment, 6.0 × 10⁵ cycles were conducted with a force of 50 N, and a 6 mm-diameter steatite ball was used as an antagonist. The amount of wear was calculated by comparing the scan files before and after the chewing simulation using 3D metrology software, and the worn cross-section was confirmed by scanning electron microscopy (SEM). The resin and ceramic groups did not exhibit any statistically significant differences. However, compared to other crown groups, the zirconia crown group demonstrated notably reduced levels of wear (p < 0.05). In SEM images, layers and cracks were observed in the 3D-printed resin crown groups, which differed from those in the other groups.

• 한국기계가공학회지
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• 제1권1호
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• pp.89-100
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• 2002

The purpose if this research was to improve the pressure distribution on the disk brake pad Not uniform pressure distribution on the disk brake pad generate the unbalance wear of it and the unbalance wear of disk brake pad generate vibration, noise, heat and reduce the braking capacity. For improve the pressure distribution on the pad in this research, upper face of caliper housing finger was cut. Two kinds of caliper which uncut and cut of finger face were compared the stress distribution by FEM analysis and real experiment. Also natural frequency and deforming displacement ware calculated. It was understood that pressure distribution could Improve by cut inside upper face of caliper housing finger.

• 한국정밀공학회지
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• 제17권12호
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• pp.82-87
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• 2000

This paper deals with monitoring of grinding wheel wear in grinding process. A monitoring system is developed in which a laser scanning micrometer is used to measure the circumferential shape as well as the axial shape of grinding wheel. The monitoring system is applied to grinding machines. The experiment results show that the monitoring system is useful not only for monitoring the amount of wear in grinding wheel but also for measuring the apparent diameter of the grinding wheel.