• Journal of Welding and Joining
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• 제17권5호
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• pp.47-54
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• 1999

It is well known that solidification cracking often occurs in welds of root pass for one-side welding under the conditions of high welding currents and speeds. In this study, the solidification in 590MPa class steel for pressure vessels SPPV490 was investigated by using flux-cored arc welding(FCAW) with 4 types of welding wires and welding conditions of 200∼280A and 2.8∼ 4.2mm/sec. In order to compared the result of cracking in SPPV490, 0.2%C steel for welded structure of SWS400 and 0.45%C steel for machine structural SM45C were also used as base metals. As the results, all the cracks formed in some welding conditions were observed near the center of weld bead. The solidification cracks were generally initiated near the upper surface of bead and propagated toward the inner part. The solidification cracking generally increased with welding current and welding speed in the same base metal and welding material. In cracking susceptibility, SPPV490 showed higher cracking susceptibility than SWS400 in all welding conditions and welding materials. It was considered that cracking susceptibility could not be evaluated with the hardness of weld metals. The cracking ratio increased with decreasing of a/b(a and b; the width of the upper surface and the back surface of the bead) as shape factor of bead. The cracking tendency with shape factor of bead was extended under the condition of higher welding currents.

• Journal of Biosystems Engineering
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• 제22권4호
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• pp.391-400
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• 1997

Using the soil bin systems, this study was carried out to investigate the tilling load characteristic for the three kinds of Japanese rotary blade and the possibility of common use for power tiller and tractor rotary. The results obtained from the study are summarized as follows : 1. At all tested soils. the average and maximum tilling torque of all tested blades increased as the tillage pitch did. 2. The torque requirements of newly designed and produced blade was less than that of blade which has been used on power tiller and tractor rotary. 3. The maximum tilling torque of new ONE were decreased 7%, 10~11％, 27% in comparing with another blades at clay loam, loam and sandy loam, respectively. 4. According to observation of the extent of soil adhesion on blade and the contact aspect of blade, new ONE is the most excellent of all tested rotary blades and till smoothly not to compress the untilled soil. From the results of this study. the newly developed blade(new ONE) proved to be good tilling load performance and had a conclusion that it is possible to use it on power tiller and tractor rotary in common.

• 복식
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• 제51권1호
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• pp.87-96
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• 2001

This study, dealing with obese bodily figures from the viewpoint of garment shape, was conducted with obese male children of late school ages(nine to eleven years old) to provide data for making ready-made clothing for obese children by directly measuring and analysing the bodily figure of the upper body of them. The results of the study are summarized as follows. 1. According to the basic statistics, for most of obese children the values of the measuring items by ages appeared to be large, and the results of comparison with the National Anthropometric Survey of Korea made in 1997 showed that the values were more large than those of standard physical conditions. 2. It was shown that in the correlation between items the upper breast circumference had a high correlation with all items, and the weight did with the following items such as circumference, height, width and thickness. 3. The results of the principal component analysis showed that six main components hand an explainable power of more than 75.60% for all materials. The first factor was thickness and obesity of the upper body, the second one the height, the third one the length of front and rear sides, the fourth one the width of neck, the fifth one the length of shoulder, and the sixth one the breast width and the wrist circumference.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권12호
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• pp.550-557
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• 2006

This paper proposes a dry-type surface myoelectric sensor for the myoelectric hand prosthesis. The designed surface myoelectric sensor is composed of skin interface and processing circuits. The skin interface has one reference and two input electrodes, and the reference electrode is located in the center of two input electrodes. In this paper is proposed two types of sensors with the circle- and bar-shaped reference electrode, but all input electrodes are the bar-shaped. The metal material of the electrodes is the stainless steel (SUS440) that endures sweat and wet conditions. Considering the conduction velocity and the median frequency of the myoelectric signal, the inter-electrode distance (IED) between two input electrodes as 18mm, 20mm, and 22mm is selected. The signal processing circuit consists of a differential amplifier with a band pass filter, a band rejection filter for rejecting 60Hz power-line noise, amplifiers, and a mean absolute value(MAV) circuit. Using SUS440, six prototype skin interface with different reference electrode shape and IED is fabricated, and their output characteristics are evaluated by output signal obtained from the forearm of a healthy subject. The experimental results show that the skin interface with parallel bar shape and the 18mm IED has a good output characteristics. The fabricated dry-type surface myoelectric sensor is evaluated for the upper-limb amputee.

• 한국가금학회지
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• 제27권3호
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• pp.255-258
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• 2000

This study was carried out to investigate the distribution and morphological properties of mast cells in the ileum of Korean pheasant. In the ileum mast cells were located in the lamina propria of mucoase. The cells were mainly oval with irregular cell surface occasionally spindle-like or triangular in shape. Some mast cells had one or more tail-like long cytoplasmic processes. All mast cells had many blue granules stained by toluidine blue in the cytoplasm.

• 수산해양기술연구
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• 제22권1호
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• pp.11-18
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• 1986

Schooling behavier to a fishing gear and estimation of the volume of fish school in set net have ~ been studied by making use of such techniques as visual observations, underwater cameras, under- water televison. However, all of these observation techniques are subject to restrictions caused by illumination, underwater visibility, underwater transparent and sea conditions. For the above mentioned reasoa, one of the most effective method by this time become generally known a method using fish finder. In this paper, in order to control the fishing ground of set net effectively and to develope the telemetric fish finder, the experiments for the target strength, underwater shape of fishing gear, schooling behavier and volume of fish school with fish finder were performed at Galgott fishing ground of set net located Keouje Island, 15th-24th July and 18th-20th October in 1985. The results of these experiment showed that a method using fish finder in fishing grOlllld of set net is available for estimating distribution and school size, fish behavier in relation to a fishing gear and underwater shape of fishing gears.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.326-330
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• 2007

Bumper back beam is one of the essential structural components of front-end module. It should be designed to withstand a minor bump in low-speed collision, 2.5 mph crash test for example. And weight reduction is always important problem in the design of almost all the parts in car for energy saving. So, the key issues in shape design of a bumper are weight reduction and the performance in 2.5mph crash test. In this study, a light weight and high performance bumper back beam model was developed using analytical approach based on mechanics and FE simulation together.

• Steel and Composite Structures
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• 제32권3호
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• pp.373-388
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• 2019

This study proposes a new concept of an axial damper using the combination of shape memory alloy (SMA), friction devices, and polyurethane springs. Although there are many kinds of dampers to limit the damages, large residual deformation may happen and it causes much repairing cost for restoring the structure to the initial position. Also in some of the dampers, a special technology for assembling and fabricating is needed. One of the most important advantages of this damper is the ability to remove all the residual deformation using SMA plates and simple assembling without any special technology to fabricate. In this paper, four different dampers (in presence or omission of friction devices and polyurethane springs) are investigated. All four cases are analyzed in ABAQUS platform under cyclic loadings. In addition, the SMA plates are replaced by steel ones in four cases, and the results are compared to the SMA dampers. The results show that the axial polyurethane friction (APF) damper could decrease the residual deformation effectively. Also, the damper capacity and dissipated energy could be improved. The analysis showed that APF damper is a good recentering damper with a large amount of energy dissipation and capacity, among others.

• 한국생활과학회지
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• 제14권6호
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• 한국의류산업학회지
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• 제20권2호
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• pp.219-225
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• 2018

The purpose of this study is to make an ideal dummy for adult Maltese with proper investigation of its character and direct measurement of dog body-shape. The results of the study are as follows; First, there were 6 factors to affect the characteristics of Maltese body in the analysis, which are size of body, leg shape, chest shape, leg thickness, body length, length between fore-legs. In the cluster analysis with the 6 factors there were two types of Maltese body. Type 1 has body characteristics with large body, thick leg, and small distance between front legs. Type 2 has average size of all factors including body size, leg thickness, and length between fore-legs. Second, type 2 was selected as a representative one to make a dummy reflected body shape of characteristics because it took 67.71% from entire considered factors and has average value in the measured size. The first dummy pattern was planned by copying the surface area of the representative body shape with the method of surgical tape. A dummy of single body with trunk and legs was made using 30's cotton cloth, polyester inside batting, compressed form PVC and metallic wire on the joint of trunk and legs to support dummy shape. The second pattern was made by correcting size difference of the pattern and adding the pattern of neck covering plate, metal magnetic button was inserted on the center of joint area of trunk and legs to make detachable legs for easy slip on and off the pet's wear.