• Transactions of Materials Processing
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• v.4 no.4
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• pp.398-409
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• 1995

The wear properties of the alumina short fiber reinforced tin-bronze matrix composites manufactured by hot pressing was studied at the room temperature and $350^{\circ}C.$ The wear loss of various specimens having different constituent and different density was examined by a pin-on-disc type wear testing machine. The results were discussed by the observation of the worn surface morphology and the analysis of the composition on the worn surfaces. Since the reinforced effect of the alumina fiber on the wear resistance was dependent on the strength of alloy matrix, the pressureless sintered composites having a lower matrix strength showed a marked increase in wear resistance by the fiber reinforcement. As the wear condition became severe, the fiber reinforcement was more effective. The delamination on the wear surface was observed in the pressureless sintered specimens having pores which are related to the initiation and the propagation of cracks. However, the wear mechanism acting on a big failure area was not found on the wear surfaces of the hot pressed specimens having a few pores.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.3
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• pp.198-203
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• 2012

Excessive occlusal wear results in unacceptable damage to the occluding surfaces, and can cause pulpal injury, occlusal disharmony, impaired function, and aesthetic deformity. Patients with severely worn dentition need to be classified as several categories relative to the vertical dimension of occlusion (VDO) and the interocclusal distance for the prosthetic space. When treating patients classified as those who have excessive wear without loss of occlusal vertical dimension but with limited space, we could consider treating them at an increased vertical dimension of occlusion. Treatments at an increased vertical dimension of occlusion may provide stability, given that the amount of its increase was minimal, and a perfected occlusion was achieved after enough stabilization period. A 50-year-old male visited the department of Prosthodontics in Yonsei University Dental Hospital with the chief complaint of worn teeth on lower anterior area. Reconstruction at an increased vertical dimension of occlusion was planned. After the compatibility of the new vertical dimension of occlusion had been confirmed under interim fixed restorations, definitive fixed restorations composed of full-contour monolithic zirconia prostheses were placed. This case presents that a satisfactory clinical result was achieved by restoring the worn dentition at an increased vertical dimension of occlusion with an improvement in esthetics and function.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.1
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• pp.65-71
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• 2016

Gradual occlusal attrition is a normal process of aging. However, severe attrition causes pathogenic pulp, occlusal disharmony, functional disorder and esthetic problems. Alteration of vertical dimension should be considered for space regaining for tooth restoration, esthetic improvement or correction of occlusal relationship. Vertical dimension should be determined within the range of minimal invasive process satisfying patient's esthetic requirements and operator's functional goal. And patient's adaptation to newly determined vertical dimension should be assessed simultaneously. Deep overbite is not a simple problem of overbite, instead it is an usually complicated problem with anterior-posterior occlusal relationship. Considering these facts, appropriate restoration of edentulous part as well as improvement of anterior-posterior relationship should be performed to solve this fundamental problems. In this study, a 67 year-old male patient with many worn teeth and loss of posterior teeth was treated with removable partial denture at edentulous mandibular area to increase vertical dimension and fixed prostheses at dentulous maxillary and mandibular area. With these treatments, we attained a satisfactory result in functional and esthetic aspects as a report case.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.4
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• pp.726-736
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• 2018

This study determined how the upper body shape of elderly women changes with age in order to improve the fit of clothing worn by elderly women. Thirty-nine healthy elderly Japanese women had their body measurements taken by measuring tape and a 3D body line scanner (Hamamatsu Model #C9036-02) from December 2011 to March 2012 at a university in Tokyo. It was found that the shoulder line shortens in women between the ages of 70 and 74, but that the upper arm lengthens in women between the ages of 75 and 79. It was also found that the upper part of the scapular area rolls forward in women between the ages of 70 and 74, and that the point of the back which protrudes the most-the lower scapular area-rolls forward in women between the ages of 75 and 79. The results will be helpful for designing clothes for elderly women as their body shape changes with age.

• Journal of the Korea Fashion and Costume Design Association
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• v.4 no.1
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• pp.85-98
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• 2002

This study aims to present basic data on current uniforms for the practical improvement and quality betterment of their design by investigating and analysing the uniform designs worn by employees working in department stores, shopping malls and financial firms. For the research, after taking pictures of employees wearing uniforms from various occupations in Daejeon area from April 15 to May 24, 2001, the uniform styles, and the shape, color and pattern of each item were analysed by a group of four costume experts. The result is as follows: First, the uniform forms are classified by the style, and silhouette. It was found that the overall silhouette mostly consisted of hourglass silhouette, and two-piece suits. Second, for the color of each item, black was the most common color for the jacket, skirt, pants and white for the one-piece dress. Third, plain, abstract, and striped patterns, and polka dots were used for the uniforms. Among them the plain pattern accounts for the highest rate.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.1-3
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• 2000

Indoor carbon monoxide (CO) concentration and personal CO exposures were measured Asan where CO poisoning from twenty coal usage briquette as a domestic fuel to cook and space heating. Twenty-five were houses selected from the Asan area for the survey conducted in February 1997. Newly developed passive CO samplers were placed in the kitchen and living room for the indoor concentration measurement and were worn by homemakers for personal exposure monitoring. The daily average of indoor CO concentration was 16ppm in the kitchen and 10ppm in the living room. The indoor concentration and personal exposures to CO were different in types of the space heating system. House ventilating methods and socioeconomic conditions were also important factors in determining the indoor and personal CO level in Asan.

• Tribology and Lubricants
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• v.5 no.1
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• pp.36-43
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• 1989

Scanning electron microscopic observations were carried out on the worn surface and the wear debris of ceramic materials to investigate the wear mechanism of those in dry rolling contact. It was found from the scanning electron microscopic observations that the wear in ceramic materials is related to brittle fracture and has two types of wear mechanisms, small scale wear and larvae scare wear. Plate-like wear debris were created from the initial surface cracks and defects. The small scale wear was related to real contact area and large scale wear was related to HertzJan contact area. A wear model was proposed on the basis of scanning electron microscopic observations.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.3
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• pp.167-179
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• 2005

Skirts hold an important position in dress culture among various dress forms, being worn by more than half of mu. In this study, Chima is defined as garment for lower part of the body without crotch sewing, contrasting with trousers. The authors classify and compare the formation of the skirts of minority races in Yunnan area, based on Korean Chima, understanding the forms of skirts and examining the composition, color, pattern and material. For the study, the authors investigated 57 pieces of skirts among 341 pieces of minority races dresses from Yunn Nationality Museum collection exhibited at Korea Folk Village in May 2003, and referred to customs materials and photos in various literatures. Skirts in Yunnan area are divided into 6 areas, that is, seamless one-piece skirt area, wrapskirt area and mixed type skirt area. Skirt formation factors from the effect of environment such as climate, lifestyle and means of production were studied, and characteristics, differences and similarities were reviewed. Figure of skirts are studied by compostion, color, material, and technique. By composition, they can be classified based on the similarity to Hanbok (traditional Korean dress). By color, worshipped color and preferred color vary by races and by area. Materials vary in kinds and thickness by area with various climate. By technique, national characteristic patterns are inherited through national traditional dyeing and embroidery. It is not easy to conclude based on single item of skirt, but we suggest that national dresses have been settled through the mutual supplements between the effect of social and cultural exchange such as historical inheritance, geological environment, religion and production activity and the various forms of skirts from changes in shape, color, material and wearing form of dresses.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.111-115
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• 2008

This study was conducted to distinguish adult morphology of the giant water bug (Lethocerus deyrollei) between over-wintered (OLD) and new-born (NEW) populations using materials collected from Gyodong island in Gyeonggi-do, Korea, as well as individuals reared in the laboratory (LAB population) as a control. As a result, no fundamental differences were found in external body structure between OLD, NEW, and LAB populations. However, marginal area of basal procoxa in ventral prothorax and jointed part of forefemur and foretibia were greatly worn in the OLD population. Mid-claws were shorter than 0.5 times the length of the 2nd mid-tarsus; the membranous margin of hemelytra was greatly worn; and hairs of the 5th abdominal tergum were greatly reduced in the OLD population.

• PNF and Movement
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• v.19 no.2
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• pp.233-242
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• 2021

Purpose: The purpose of this study was to determine the changes in foot contact area and pressure when walking with a functional insole that emphasizes the Hallux point as compared to a general insole. Methods: In this study, an experiment was conducted to investigate changes in plantar pressure and contact area for a functional insole that emphasized the Hallux point as compared to a general insole. A lower extremity robot was used for walking reproduction. First, the gait sequence according to the two insoles was determined through a randomized controlled trial comparison. According to the sequence procedure, the insole was attached to the shoe and then worn on the right side of the lower extremity robot for gait reproduction at a normal gait speed of 20 steps per minute. After programming the robot to walk, the experiment was carried out. The result value was determined by averaging the pressure and area data of the fore and rear foot measures after walking at 20 steps per minute. Results: The functional insole that emphasized the hallux point significantly increased the forefoot and rearfoot contact area (p < 0.05) and significantly decreased the forefoot and rearfoot contact pressure (p < 0.05) compared to the general insole. Conclusion: A functional insole that emphasizes the hallux point does not collapse the medial longitudinal arch during gait, increasing foot stability and reducing fatigue. Thus, this functional insole needs to be widely used clinically.