• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1995년도 추계학술대회논문집
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• pp.181-187
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• 1995

The effet of glass fiber and graphite on the wear properies in tin-bronze alloy matrix composites was studied by a pin-on-disk type wear testing machine. The results obtained from the wear test were analized by SEM observations of worn surfaces of pins and disks and EPMA composition measurments. The amount of wear was devreased as increasing the content of glass fiber in matrix, since the alloy matrix was reinforced by glass fibers. The wear mechanism of the matrix specimen without glass fibers was proved as the contact area delamination. Oxide layer formed on sliding surface led to the increasing wear resistance. Specimens containing graphite particles showed an lubrication effect to counter disks.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.105-111
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• 2003

The valve train system of engines has long been a sensitive area with respect to wear performance because of the high contact loads and surface sliding speeds encountered. In particular, wear problems of load-carrying components in relative motion, such as cam and tappet in valve train system have made troubles. To overcome these problems, combination of proper materials is important, as well as selecting of high wear performance materials. This paper presents the experimental result of friction and wear properties of ca/tappet materials. To investigate friction and wear properties for several combinations of materials, using commonplace tribometer(Plint 77, reciprocating type), we make a selection of a optimum material combination.

• Tribology and Lubricants
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• 제25권2호
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• pp.120-124
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• 2009

In automobile chassis system, several environmental factors weaken durability of automobile's components. The environmental factors are temperature, humidity, intensity of radiation and dust particle inflow. Especially, dust particle inflow leads to increase in friction and wear of automobile's components. The wear of automobile's component leads to increase in noise and exerts a bad influence on life of components. In this study, dust particles were investigated for study on the influence of dust particle inflow. Dust particles are collected on urban area, rural area and highway in China. The size of dust particle is analyzed using the image plus program, and the element of dust particle is analyzed using the SEM and EDX. The elements of dust particle are $SiO_2$ and $Al_{2}O_{3}$. The other elements(Na, Ca, Cl etc..) are detected on urban area and highway.

• 복식
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• 제52권8호
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• pp.29-39
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• 2002

It was increased leisure hours by automation and computerization of industry. Many people spend on hours in enjoying leisure sports, and then. nowadays, Many women tend to prefer casual wear to formal suits. The purpose of this research was to design of outdoor-wear that improve the functional and aesthetic effects for clothing comfort. Total 4 design prototype consisting of jumper and slacks were developed for this research. Outdoor-wear design forced on armhole type of jumper and ease of the back crotch length of slacks to improve the functional and aesthetic effects. And Outdoor-wear design focused on color harmony to aesthetic effects. Ease amount and materials of jumper and slacks were controlled. Design A: Jumper was designed as dropped shoulder with set-in steeve and band collar, A break-away zipper to facilitate ventilation control were made the area of back of jumper and the area of outside seam line of slacks Color of jumper and slacks were olive green color. Ease amount of the crotch length of slacks pattern was constructed as 7% of total crotch length: Design B 4DM cut pattern were applied to the jumper and slacks pattern. A break-away zipper to facilitate ventilation control were made the area of back of jumper and the area of inside seam line of thigh. Color of jumper and slacks were grey and orange color. Ease amount of the crotch length of slacks pattern was constructed as 5% of total crotch length. Design C : Jumper was designed as the set in sleeve and hood. and A break- away zipper to facilitate ventilation control were made the ares of the armhole and elbow. Color of jumper and slacks were ivory and orange color. Ease amount of the crotch length of slacks pattern was constructed as 5% of total crotch length. Design D : Jumper was designed as raglan sleeve. Color of jumper and slacks were olive green color. Ease amount of the crotch length of slacks pattern was constructed as 5% of total crotch length. Total six females, ages 20-45, served as subjects for this research. Subjects have standard body type, generally, wearing 66 size of ready-to-wear clothing. The performance of the newly designed outdoor-wear was evaluated for their effectiveness in several aspects such as conditions of skin temperature, sensory evaluation of comfort during body movements, appearance and color harmony and aesthetic collar design. Design 3 was appeared to be the most positive in aesthetic evaluation and functional effects of design 2 of 4DM cut pattern was appeared to be beter than other designs.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.175-178
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• 2008

플래시 메모리에서 읽기 작업은 속도도 빠르고 제약이 없으나 데이터 변경 시에는 덮어쓰기(overwrite)가 되지 않아 해당 데이터를 새로운 영역에 쓰고 이전에 존재하던 데이터는 무효 시켜야한다. 무효화시킨 데이터는 가비지컬렉션을 통해 지움 연산을 수행해야 한다. 지역 접근성을 가지는 데이터에 대해 가비지컬렉션을 통해 클리어 시킬 대상 목록을 선정할 때 cost-benefit 방법을 사용하면 성능은 좋으나 wear-leveling이 나빠지는 문제점이 있다. 본 연구에서는 wear-leveling을 개선하기 위해 플래시 메모리를 hot 데이터 그룹들과 cold 데이터 그룹들의 다수의 그룹으로 분할한 후 데이터를 배치하고 주기적으로 hot 데이터 영역과 cold 데이터 영역을 교체함으로써 wear-leveling과 성능을 개선하였다.

• 한국생활과학회지
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• 제23권4호
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• pp.681-695
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• 2014

This study has the purpose to find basic materials for development of kindergarten's uniform and suggest the improvement of its design based on the survey results from Suncheon area in Jeollanam-do of Korea. Such study methods were conducted as literature review, survey with direct visit, interview, and photographing of dresses regarding the kindergarten uniform. The following are research results. First, kindergarten teachers presented a positive opinion about the necessity for children to wear the uniform. In selection of design, they regarded the activity as most important factor. Kindergartens applying active wear compatible as townwear also accounted for 57.1%, which is more than half. Second, the formal wear, in the winter season was found to consist with jacket or knit cardigan, knit vest, shirts, skirts or pants, and necktie. For color, most of them are in dark tone, which need to be brighter. For pattern, they are in plain color, which needs to have various patterns. As to the cloth material, such problems should be improved as warmth retentivity in consideration of seasonal nature, moisture retentivity, breathability, color retentivity when washing, and harmless to human body. Third, active wear is mostly the casual sportswear type. But it has no characteristic unique to kindergarten in design and needs to be altered for differentiated design. Especially, it is simply divided into winter wear and summer wear in kind. Therefore, it is required to have differentiation for seasonal characteristic and diversity in number of item and improvement in terms of cloth material.

• 한국정보통신학회논문지
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• 제12권1호
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• pp.108-114
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• 2008

플래시 메모리는 디스크와는 달리 덮어쓰기가 불가능하므로, 새로운 데이터는 새로운 영역에 갱신이 된다. 데이터가 빈번히 변경되면 새로운 영역을 확보하기 위해 가비지 컬렉션을 통하여 데이터를 지우게 되는데, 이때 지움(erase) 연산을 수행 할 수 있는 회수가 플래시 메모리의 특성에 의해 일정 회수로 제한을 받게 되므로 플래시 메모리의 모든 블록은 고르게 쓰여지고 지워져야 한다. 그러나 지역 접근성을 가지는 데이터를 Cost-benefit 방법으로 처리하면 성능은 좋으나 wear-leveling은 매우 나빠지는 문제점이 있다. 본 논문에서는 wear-leveling을 개선하기 위해 멀티 뱅크에서 하나의 뱅크는 cold 데이터를 다른 뱅크는 hot 데이터를 할당하고, 시간이 흐름에 따라 일정주기로 cold 뱅크와 hot 뱅크를 교환하는 CB-MB(Cost Benefit between Multi Bank) 방법을 제안하고 성능을 평가하였다. CB-MB방법은 hot 데이터와 cold 데이터를 블록단위로 분리하여 관리하는 Cost-benefit방법에 비해 성능에 있어 30% 성능향상을 보이고 wear-leveling측면에서 1/3이하로 표준편차를 줄였다.

• 한국재료학회지
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• 제12권8호
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• pp.608-612
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• 2002

The sliding wear behavior of an iron-base NOREM 02 hardfacing alloy was investigated in the temperature range of $25～250^{\circ}C$ under a contact stress of 103MPa (15ksi). With increasing temperature, the wear loss of Norem 02 in water increased slightly up to $180^{\circ}C$ at which Norem 02 showed the wear loss of 2.1mg. The wear resistance of Norem 02 resulted from the surface hardening due to the strain-induced phase transformation from austenite to $\alpha$'martensite during sliding wear. The wear loss of Norem 02 was smaller in water compared to air at same temperature because the water could be served as a sort of lubricant. The wear mode of NOREM 02 changed abruptly to severe adhesive wear at $190^{\circ}C$ and galling occurred above $200^{\circ}C$. It was caused that the strain- induced phase transformation took place below $180^{\circ}C$ while not above $190^{\circ}C$. Therefore, Norem 02 was considered to be inadequate at high temperature service area.

• 한국정밀공학회지
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• 제18권11호
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• pp.148-154
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• 2001

Drilling is one of the most important operations in machining industry and usually the most efficient and economical method of cutting a hole in metal. From automobile parts to aircraft components, almost every manufactured product requires that holes are to be drilled for the purpose of assembly, creation of fluid passages, and so on. It is therefore desirable to monitor drill wear and hole quality changes during the hole drilling process. One important aspect in controlling the drilling process is monitoring drill wear status. A drill-wear monitoring system provides information about drill status. With the information, optimum planning for tool change is possible. And drill-wear monitoring system in needed to evaluated drilled hole quality and the wear of drill. Accordingly, this paper deals with an on-line drill wear monitoring system of the detection of tool wear with the computer vision and the area of the drill flank wear is analyzed quantitatively by the system.

• 한국의류산업학회지
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• 제21권1호
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• pp.75-87
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• 2019

The purpose of the study was to suggest a cycle wear top jersey improved in mobility. The study developed a new cycle wear with improvement in dissatisfaction factors by planning design, pattern and the functionality of fabric. Considering the amount of sweat and the necessities of compression part, the basic material, the additional compression material, and the mesh material were arranged differently according to areas. The assessment of the developed cycle wear was composed of wearing comfort evaluation by female cyclist, photo analysis and garment pressure evaluation. The developed cycle wear was evaluated and compared with the current cycle wear. As a result of wearing comfort evaluation, the developed cycle wear was evaluated as better than the existing ones in all part, particularly in the areas of reflection tape and materials, partial pressure, pocket size, and prevention of loss. Photo analysis was in agreement with the appearance evaluation of the participants. As a result of garment pressure evaluation, the front neck part was more comfortable and the upper arm, abdomen, and waist area showed higher pressure, so it partially supported the body. This study has significant meaning for developing a new cycle wear top, protecting the body and improving the exercise effect.