• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.752-760
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• 1993

We research ed on the noise control of a head feeding type combine harvester. It is a kind of combine harvester developed in Japan. And at present, it is used by most Japanese farmer. For a head-feeding type combine harvester it is very difficult to determine the sources of noise because it is a combination of reapers and automatic , threshers and several running parts. However we succeeded in finding out the sound sources of combine harvesters and analyzing their sound by the using sound intensity method. The sound intensity Method is a very up-to-date method to measure and analyze Sound Intensity Levels and sound directions at several measuring point sin a specified area. In this research, first a conventional sound level measurement method is used and secondly the sound intensity method. The first method shows a rather great limitation in allowed exposure duration. The second method shows pin-points the engine itself as being the main source of noise, causing sound flows a ross the operator's seat.

• Biomolecules & Therapeutics
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• v.15 no.4
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• pp.235-239
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• 2007

In order to evaluate the improvement effects of head of Panax ginseng on chronic arthritis, we have investigated the activity of butanol fraction (BuOH fraction) in vitro and in vivo system. BuOH fraction showed significant inhibition on the elastase activity. Anti-arthritic activity of BuOH fraction was also examined on type II collagen-induced arthritis in DBA/1J mice. Mice were immunized with injection of type II collagen emulsified in Freund's complete adjuvant, followed by a booster injection 21 days later. BuOH fraction(BHPG) was administered at an oral dose of 500mg/kg for 2 weeks from the 1st day boost. The hind paw edema was significantly decreased in the group of treatment with BuOH fraction compared to control. In collagen-induced DBA/1J mice, BuOH fraction did not affected the collagen antibody titer but significantly inhibited the tumor necrosis factoralpha(TNF-${\alpha}$) activity. These results were confirmed with histological evaluation of joint tissues. This study may raise the possibility that the usage of BuOH fraction of head of Panax ginseng as alternative medicine for the relief and prevention of rheumatoid arthritis symptoms.

• Progress in Superconductivity and Cryogenics
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• v.14 no.3
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• pp.48-52
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• 2012

This paper describes experimental study on the orientation dependence of GM-type pulse tube refrigerator with helium and neon as working gas. A pulse tube refrigerator generates refrigeration work with gas expansion by gas displacer in the pulse tube. The pulse tube is only filled with working gas and there exists secondary flow due to large temperature difference between cold-end and warm-end. The stability of secondary flow is affected by orientation of cold-head and thus cooling performance is deteriorated by gas mixing due to secondary flow. In this study, a single stage GM-type pulse tube with orifice valve as a phase control device is fabricated and tested. The fabricated pulse tube refrigerator is tested with two different working gases of helium and neon. First, optimal valve opening and operating frequency are determined with experimental results of no-load test. And then, the variation of no-load temperature as orientation angle of cold-head is measured for two different working gases. Effect of orientation dependence of cold-head as working gas is discussed with experimental results.

• Design & Manufacturing
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• v.15 no.4
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• pp.32-36
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• 2021

In this study, the cause of the decrease in transmittance of the outer lens among the causes of the decrease in the amount of light in the automobile headlamp was identified, and the improvement method was selected to determine the effect. The causes of defects that lower the transmittance of the outer lens are divided into a moisture problem and a haze problem. The moisture problem is caused by the temperature difference between the inside and the outside of the head lamp, and the haze problem occurs when the heat inside the head lamp evaporates the haze component contained in the plastic material and attaches it to the outer lens. In order to improve the haze problem that occurs in plastic raw materials, the structures of the bulb light source type headlamp and the LED chip light source type headlamp were analyzed. Among them, the housing material of the LED chip light source type headlamp, which is structurally prone to haze gas, was selected as the test target. In the mass-production injection process of the housing, the drying process was selected as a method to minimize haze gas without adding a separate production process. After extracting a sample every drying time at a constant drying temperature, the sample was put into a haze tester and the residual amount of haze gas was measured. As a result, it was confirmed that the residual amount of Haze gas in the material decreased as the drying time increased.

• The Journal of the Korean dental association
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• v.10 no.5
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• pp.305-306
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• 1972

Authors observed the variety of number of head of external pterygoid muscle from 70 Korean subjects. 1) The number of head of external pterygoid muscle were divided into several types. The two heads was the most common type and 1.4% in one head and 5.7% in three heads. 2) No significantly different data were found between the Korean and the Japanese.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.183-192
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• 2004

The effect of eight varieties of grain and forage type whole crop rice (Oryza sativa L Japonica) each harvested at four stages of maturity were investigated for morphology and yield, proportion of botanical fractions, fermentatability and chemical composition in an $8{\times}4$ factorial experiment. All crops were sown in 1997 at Saitama Prefecture, Japan under identical condition and harvested on 10, 22, 34 and 45 days after flowering in 1998. Total DM yield of forage type varieties was similar to that of the highest yield of grain type varieties. However, while yield of forage type varieties was attributed to higher proportion of straw than head, the reverse was in the case of grain type varieties. Yield in line with the proportion of head increased (p<0.001), but in contrast proportion of straw decreased (p<0.001) with the increase in maturity. Silage fermentability of grain type varieties was better than forage type varieties. Fermentability improved with the increase (p<0.001) in maturity suggesting that the moisture content should be reduced to improve fermentation quality. Forage type varieties contained higher (p<0.001) ash, crude fat (EE), organic cell wall (OCW) and acid detergent fiber (ADF), but contained lower crude protein (CP), organic cell content (OCC), CP in OCC and nitrogen-free cell wall extract (NCWFE) than the grain type varieties. The ash, CP, EE, Oa (60% digestible OCW), Ob (40% digestible OCW), OCW, ADF and acid detergent lignin (ADL) decreased (p<0.001), but OCC and NCWFE increased (p<0.001) with the increase in maturity. It is concluded that stage of maturity not only increases yield and proportion of head, but also improved the fermentation quality and increases quality chemical composition (except CP) of whole crop rice. Forage type varieties may be as good as grain type varieties in terms of yield, but fermentation quality and chemical composition may not be as good as that of grain type varieties.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.6
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• pp.685-692
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• 2006

In a general centrifugal pump, if it is operated in a two-phase flow the activity of the impeller usually degrades and occasionally losses its function. However, the effect of break down of centrifugal pump due to entrained air has not been clarified yet. This paper shows the air-water two-phase flow characteristics of closed type and semi-open type impellers. In a sing1e-phase flow, closed-type impeller has higher efficiency and head. But in air-water two-phase flow semi-open type impeller's rates of decreases of efficiency and head are decreased.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.330-335
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• 2014

This study was conducted to investigate residue levels of chlorantraniliprole and ethaboxam in inner part and outer leaves of a head-type Korean cabbage. Further, reduction of residues was measured after water washing, blanching and heat-cooking of the outer leaves. For chlorantraniliprole, residues in inner part and outer leaves were <0.01 mg/kg and 0.0757 mg/kg, respectively, in case of three-time spraying 30 days before harvest and <0.01 mg/kg and 1.19 mg/kg, respectively, in case of four-time spraying 10 days before harvest; for ethaboxam, <0.05 mg/kg and 0.216 mg/kg, respectively and <0.05 mg/kg and 1.18 mg/kg, respectively. Chlorantraniliprole and ethaboxam were not detected in inner part of the head-type Korean cabbage. Residue levels in outer leaves were very high as 10-100 fold as those in inner part of the cabbage. Therefore, there is no concern for safety of pesticide residues on kimchi prepared with the inner part of a head-type Korean cabbage. In addition, it needs to be noted that outer leaves should be carefully removed at harvest of the cabbage. Outer leaves water washed and blanched are called as Woogeogi, which is consumed after heat-cooking. In Woogeogi, residue concentrations of two compounds reduced to less than 10%, and further less than 5% by heat-cooking. This indicates that considerable amount of the test pesticide residues in outer leaves of a head-type Korean cabbage removed through water washing, blanching and heat-cooking.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.47-49
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• 2003

수직 기록 방식은 그 기록 방식의 차이로 인하여 수평 기록 방식에서 쓰여 오던 Write Head의 Design을 적용하였을 경우 기록 밀도를 높이는데 많은 문제점과 낮은 기록 밀도 상승률을 동반하게 된다. 따라서 수직 기록 방식의 자기 기록에서는 수직 기록 방식에 적합한 Write Head의 Design을 적용하여야만 한다. 본 논문에서는 3차원 유한요소법을 이용하여 수직 기록용 Write Head의 한 종류인 SPT Head(Single Pole Tip Head)를 최적 설계하여 그 Write Field의 특성을 분석 제시하였다. 또한 기록 Media의 차이에 따른 기록 특성을 분석하기 위하여 기존 Single Layer 방식과 SUL (Soft Magnetic Under layer)를 사용한 Double Layer 방식을 이용하였을 경우 SUL이 자기 기록에 미치는 영향에 대한 내용을 연구 분석하여 제시하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.2
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• pp.121-127
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• 2008

This paper presents design and fabrication of optimized geometry structure of electrostatic inkjet head. In order to verify effect of geometry shape, we simulate electric field intensity according to the head structure. The electric field strength increases linearly with increasing height of the micro nozzle. As the nozzle diameter decreases, the electric field along the periphery of the meniscus can be more concentrated. We design and fabricate the electrostatic inkjet heads, hole type and pole type, with optimized structure. It was fabricated using thick-thermal oxidation and silicon micromachining technique such as the deep reactive ion etching (DRIE) and chemical wet etching process. It is verified experimentally that the use of the MEMS inkjet head allows a stable and sustainable micro-dripping mode of droplet ejection. A stable micro dripping mode of ejection is observed under the voltages 2.5 kV and droplet diameter is $10\;{\mu}m$.