• International Journal of Precision Engineering and Manufacturing
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• 제2권4호
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• pp.40-46
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• 2001

Bulging is a forming method to shape die cavity by using hydraulic pressure in tube or vessel. Bulging machine and die were developed in order to produce vessel for keeping warm. Bulging machine is a double type with two horizontal cylinders for bulging of two pieces at the same time. The developed die system has one bulging die and two drawing dies for necking at both ends of the tube. The diameter of tube expands by hydraulic pressure in tube. At the same time, thrust at both ends of the tube pushes tube in the direction of expansion to obtain high expansion rate with no crack. In this study, the bulging properties were investigated to solve tube crack and necking in manufacturing vessel by combining bulging and drawing. As a result, high expanding rate of tube radius without crack, precision necking and high productivity were obtained.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1995년도 제2회 단조심포지엄 단조기술의 진보
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• pp.135-144
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• 1995

Cold Forging has advantage in high accuracy and short working time. However large-skzed and complicated parts are difficult to process with cold forging. Thus large-sized and complicated parts have been processed with two pieces, or combind forging that is hot forging in addition to cold sizing. Recently, large-sized and complicated parts can be manufactured with cold forging alone by advanced cold forging technology using the long-stroke press. In this paper, cold forging technology of large-sized and complicated parts are investigated, including tripod slide housing for constant velocity joint and drive shaft for starter.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.37-41
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• 1997

Tailored Blanks are defined as two or more separate pieces of sheet material having the same or dissimilar thickness and/or physical properties, joined together before forming. Its application is being increased especially in the automotive industrial area for the cost reduction, weight saving, and improvement of strength. In this paper, the deforming behaviour of the laser welded blanks with regard to different thicknesses and combinations are described through some experimental investigations on the formability of a door inner. To investigate how the combination of thickness and material property influences the movement of welding line, a series of laser welded T/B blanks are tested.

• 한국해양공학회지
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• 제23권1호
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• pp.152-157
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• 2009

In designing and manufacturing a submarine, an expensive real mock up is usually built as a reference because of the spatial constraints of a submarine. This paper presents an integrated and automated design process for a submarine that uses a digital mock up. Various equipment libraries are built for feature based design. Using the developed digital mock up, this paper shows various ways to verify the design, including a space analysis to check for any interference between pieces of equipment and the hull and an ergonomic analysis using lifelike dummies to examine the work space and operability. As a part of the integrated design system, a design automation system was also developed to generate surface point data for the outer hull, pressure hull, casing, and sail. The whole process was applied to the design of a submarine for verification.

• 한국세라믹학회지
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• 제49권1호
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• pp.90-94
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• 2012

This study has been focused on properties of mirror surface grinding technology by ELID(Electrolytic In-process Dressing) for metal matrix ceramic composites using in high precision mirror for optics. The experimental studies have been carried out to get mirror surface by grinding for composites, Al-SiC, Al-graphite and Mg-SiC. Grinding process is carried out with varying abrasive mesh type, depth of cut and feed rate using diamond wheel. The machining result of the surface roughness and condition of ground surface, have been analyzed by use of surface roughness tester and SEM measurement system. ELID grinding technology could be applied successfully for the mirror-surface manufacturing processes in spite of ductility of metal matrix material. As the results of experiments, surface roughness of Al-SiC(45 wt%) has been the most superior in these experimental work-pieces as 0.021 ${\mu}m$ Ra.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.302-307
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• 1990

An automatic visual classification system is introduced which provides for measuring the length and diameter of coilform cores and dividing them into 5 different classes in terms of how far their length be from the desired length. This task is fully automated by controlling two STEP motors and by using image processing techniques. The classification procedure is broken into three logical parts. Fist, cores in the form of randomly stacked bundle are lined up one by one so as to be well captured by a cameras. The second part involves capturing core image. Then, it enters the measuring process. Finally, this machine would retain all tire information relating to the length. According to the final result, cores are sent to the corresponding bin. This considerably simplifies the selecting task and facilitates a greatly improved reliability in precision. The average classifying capability about 2 pieces per second.

• 산업공학
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• 제3권2호
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• pp.1-11
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• 1990

In this study, we will present a knowledge-based consulting system, called THYCONS, for diagnosing thyroid disorders. It has been developed to make the knowledge and expertise of the human expert more widely available, therefore achieving a high-quality diagnosis. Frames will be used to represent the medical knowledge of thyroid disorders, and several rules are attached in each slot of a frame. The uncertainty of diagnostic processes is manipulated by the subjective Bayesian method under the assumption that the pieces of evidence are conditionally independent. Searching for the group of diagnostic tests to be carried out and their optimum sequences will be established in order to infer a more correct diagnosis on the basis of maximum information gain with cost and time restrictions. Additionally. differential diagnosis will be carried out based on the information gained.

• 대한가정학회지
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• 제44권1호
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• pp.139-150
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• 2006

Eighty-four fabrics, all weaved from silk, were excavated from Kim Yeoon's tomb. They comprised 51 pieces of silk tabby, 13 of satin damask, 17 of twill, and 2 of complex gauze, 1 of damask on tabby. The fabrics featured high quality of satin, a uniquely patterned satin damask, various silk tabbies, and 3-end complex gauze. The names of the fabrics used in this article are based on literature sources and include silk tabby(紬), thin silk tabby(紬), filament silk tabby(絹), satin damask(段), complex gauze(羅), simple gauze(紗), and twill(綾).

• 한국의류산업학회지
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• 제3권2호
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• pp.124-130
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• 2001

It is said that the highlights of Naadam festival, the biggest festival of the year in Mongolia, are three athletic contests: wrestling, horse racing, and archery, where contestants display their courage, strength, dexterity, and marksmanship. This paper explores the characteristics of the uniforms worn in such athletic events The findings are as follows. First, wrestlers' costume is completely unique in that it consists of shuudag, snug shorts, zodog, a jacket with sleeves but with no front, a traditional hat, and gutul, traditional boots. The main material used in the costume is several pieces of embroidered red or blue silk. Second, horse riders, usually young children lighter than the adults in weight, wear a bright, colorful, and comfortable uniform of a simple jacket and a pants. Third, archers' mostly put on their traditional costume, deel and hats. The hats are of two kinds: the traditional ones or the European-style ones for men, which were introduced around 1930s.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.673-678
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• 2000

This paper presents an indirect compensation of thermal errors during machining, in which thermal error is modeled as a linear regression of temperatures measured at 4 specified positions. In this regression model, weighting coefficients of the measured temperatures were estimated by using the least square method. The grinding test with compensation, after 4-hour warming-up operation before the test, showed that the maximum machining error of the work pieces was reduced to 12${\mu}{\textrm}{m}$ while it measured 28${\mu}{\textrm}{m}$ without compensation. Furthermore the standard deviation of machining errors was also reduced from 8${\mu}{\textrm}{m}$ to 2${\mu}{\textrm}{m}$.