• Journal of the Society of Naval Architects of Korea
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• v.40 no.2
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• pp.57-62
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• 2003

The block assembly of ship consists of a certain type of heat processes such as cutting, bending, welding, residual stress relaxation and fairing. The residual deformation due to welding is inevitable at each assembly stage. The geometric inaccuracy caused by the welding deformation tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding deformation. The validity of the prediction method must be also clarified through experiments. This paper proposes a simplified analysis method to predict the welding deformation of panel block structure. For this purpose, a simple prediction model for fillet welding deformations has been derived based on numerical and experimental results through the regression analysis. On the basis of these results, the simplified analysis method has been applied to some examples to show its validity.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.91-101
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• 1988

The purpose of this study was to evaluate Ultrasonic devices in root canal enlargement, about the effects on the canal shape and on the cutting ability beyond the curvature in curved canals. 180 resin blocks with $40^{\circ}$ curvature in apical third and 16mm long canal were made of epoxy resin and smooth broaches. These blocks were devided into six groups. According to the devices (ENAC$^{(R)}$, HARMOSONIC$^{(R)}$, Sonic Air MM 3000$^{(R)}$) and files (Zipperer file, H-file, Flexofile, K-file, Sharper file), five groups were instrumented one minute with # 15 files, then the enlarged size was measured. And # 20 files were used again in the same groups, then the enlarged size was measured. In control group, the time which was taken to enlarge the canal from # 15 to # 20 by hand technique was measured. The data was analyzed statistically. Then the enlarged shapes were evaluated in six groups with the stereomicroscope and recorded in ideal and non-ideal canal shape to compare the effects of ultrasonic devices on the canal shape. Only the ideal shaped canals were used in the study whether the cutting ability beyond the curvature in curved canals was, or not. The files with whole flutes, no flutes, and flutes in apical 5mm only were used. The weight differences of pre-and post-instrumentation by Sonic Air MM 3000$^{(R)}$ for two minutes were compared. The results were as follow: 1. Intracanal instrumentation for 1 minute with ultrasonic devices using # 15 and # 20 file in curved root canal of the epoxy resin block can not reach to the next file size. 2. Sonic Air MM 3000$^{(R)}$ shows higher cutting ability than the other two devices (p=0.001), however the percentage of non-ideal canal shape was the highest. 3. Two ultrasonic devices except Sonic Air MM 3000 considered normal in ideal canal shaping ability. 4. little cutting ability was shown beyond the curvature of curved canals.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.745-748
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• 1999

Background: A definitive cure for an essential hyperhidrosis can be obtained by an upper thoracic sympathectomy. However, this is offset by the occurrence of a compensatory hyper hidrosis as a side effect and it is irreversible. We performed a thoracoscopic sympathetic chain block using an endoscopic clip in order to avoid the compensatory hyperhidrosis. Material and Method: From Aug. 1998 to Nov. 1998, 42 cases of thoracoscopic clipping of the T2 sympathetic chain were performed. The sympathetic chain was clipped using an endoscopic clip instead of cutting. Result: Bilateral procedure took less than 40 minutes and occasionally necessitated one night in the hospital. There were no mortality nor life- threatening complications. Horners syndrome occurred in two cases. At the end of postoperative follow-up(median 3 months), 95.0% of the patients were satisfied with the results. Compensatory sweating occurred in 31 cases(77.5%) where nine of those cases were classified as either embarrassing(6 cases-15.0%) or disabling(3 cases-7.5%). Conclusion: Endoscopic thoracic T2 sympathetic chain block using endoscopic clipping is an efficient, safe and minimally invasive surgical method for the treatment of palmar and craniofacial hyperhidrosis and the results were similar to those underwent T2 sympathicotomy. We recommend that patients receive endoscopic sympathetic chain block in summer.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.2
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• pp.127-131
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• 2004

A low-cost, simple strip reader system using a linear movement mechanism of CD-ROM deck has been developed to characterize a lateral flow membrane-based immunochromatographic assay. The test strip reader was assembled by a CD-ROM deck and home-made optical head especially designed for immunoassays. The optical head for detecting reflected light from the test strip surface consists of green light-emitting diode, large area silicon photodiode, and anodized aluminum mounting block providing a slit structure for cutting light from the LED. The stepping motor of the deck was operated in the full step mode, whose distance of each reading point is about 0.15mm. The performance of the strip reader was tested by analysis of HBV(hepatitis B virus) antigen test kit. This strip reader can be useful for inexpensive, disposable, and membrane-based assays that provide visual evidence of the presence of an analyte in a liquid sample.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.221-226
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• 1999

It can be acquired the high effective productivity through of high speed, precision of machine tools, and then, machine tools will be got a competitive power. Industrially advanced countries already developed that the high speed feed is 50m/min using the high speed ball screw. Also, a lot of problems have happened the feed and servo drive system. It is necessary to study about the character of positioning accuracy, heat generation and high speed/accuracy control for feed/servo drive system of high speed/accuracy. In this study, we make use of high performance vertical machine center with a ball screw of large-scale-lead. Also, we'll apply the high-speed/accuracy control technology in this part of feedforward control, multi-buffering block size, etc. Using the design of the mechanical element and high-speed precision control, the basic design concept can be established.

• Tribology and Lubricants
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• v.11 no.5
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• pp.66-70
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• 1995

In this investigation, a controlled-environment tribological test device has been used to study the friction coefficients of several grades of commercially-available coated and uncoated cemented carbide cutting tools in a dry air environment at different environmental chamber pressures. Tests were run in the block-on-ring configuration. The results suggest that the friction coefficient is sensitive to the level of air present, with a noticeable rise in friction coefficient with decreasing pressure or increasing vacuum level. The uncoated cemented carbide sufaces resulted in the highest friction values, whereas the coated grades yielded somewhat lower values even after the coating was removed. The results suggest the importance of friction control in the design of coatings for metal removal processes.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.337-340
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• 2007

냉간단조금형(Cold Forging Die)의 다이블록(Dieblock)을 제작하는 방법 중의 하나로, 다이블록 제작용 재료를 면가공 하여 다이블록 상면(上面)을 마스터펀치(Master Punch)인 호브(Hob)로 압입(Indentaion) 시켜 절삭가공((Cutting Work)이 아닌 다이호빙(Die Hobbing) 방법으로 임프레션(Impression)을 성형하여 제작하고 있다. 이 방법에 의하여 다이블록의 재료를 합금공구강(Alloy Tool Steel)인 SKD11을 사용하여 제작하고, 스테인리스판(Stainless Sheet Metal)을 제품 재료로 하여 냉간단조가공(Cold Forging Work)을 하였더니 6,000 스트로크(Stroke)에서 금형수명(Die Life)을 다 하였다. 본 논문에서는 다이블록 재료를 고속도공구강(High Speed Tool Steel)인 SKH51로 교체 제작하고, 탄소강(Carbon Steel)인 S45C를 제품 재료로 하여 냉간단조가공을 수행 하였더니 21,000 스트로크에서 금형수명을 다하고 종료 되어 종래의 방법과 비교 검토 하였을 때 350%의 금형수명 연장 효과를 얻게 되었다.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.758-765
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• 1999

Comparative studies of the effects of rates and frequency of application of dairy slurry on herbage yield and stand persistence of alfalfa and various forage grasses have not previously been conducted. The results being reported here are part of a larger study having a primary objective of comparing the effectiveness of alfalfa (Medicago sativa L.), various grasses and alfalfa-grass mixtures for utilizing nutrients from applied dairy slurry. The objectives of this part of the study were to evaluate the effects of various rates and frequencies of application of slurry on herbage yield and stand persistence of orchardgrass (Dactylis glomerata L.), reed canarygrass (Phalaris arundinacea L.), and alfalfa-orchanrdgreass and alfalfa-reed canarygrass mixtures managed as a 4-cutting management system. A randomized complete block design with treatments in a split plot arrangement with four replicates was used. The main plots consisted of 9 fertility treatments: 7 slurry rate and time of application treatments, one inorganic fertilizer treatment, and an unfertilized control. The sub-plots consisted of the two grasses and two alfalfa-grass mixture mentioned above. Slurry was composed from stored solids scraped from the alleyways of a free-stall housing barn and water added to form a slurry having about 8% solids. Manure was pumped from a liquid spreader tank into 10.4 L garden water cans for manual application to the plots. Herbage yields within species were generally unaffected by various rates of application in the first production year. Herbage yields of grasses and alfalfa-grass mixtures the second year were generally not affected by frequency of application for the same rate of slurry applied. Slurry application resulted in greater herbage yield increases in grasses than alfalfa-grass mixtures in the 4-cutting management system. In general, herbage dry matter yields of grasses from the dairy slurry treatments equaled or exceeded yields from the inorganic fertilizer treatment. Stand ratings of grasses and alfalfa-grass mixtures were not changed by manure application rates. In this study, the highest rate of slurry ($967kg\;total\;N\;ha^{-1}$ in 1995 plus $2,014kg\;N\;ha^{-1}$ in 1996) was not detrimental to herbage yields or stand persistence of any of the species. It was concluded that applying dairy slurry to these cool-season grasses and alfalfa-grass mixtures managed in a 4-cutting system is an acceptable practice from the standpoint of herbage yield and satnd persistence and by doing so the utilization of inorganic fertilizers can be reduced.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.281-285
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• 2008

Die hobbing is one of the dieblock manufacturing methods of cold forging die, which makes the upper side of dieblock indented using master punch, hobb to produce impression not using cutting work. SKD11, alloy tool steel was used as the material of dieblock and stainless sheet metal was used as product material in cold forging work. The life span of the die was 6,000 strokes. In this research, the material of dieblock was changed into SKH51, the high speed tool steel and the product material was S45C, the carbon steel in the cold forging work. The life span of the die was 21,000 strokes, which is 350% of the life span of the die using the former method.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.799-814
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• 2021

Information is lacking about the effect of date of a fall cut of alfalfa (Medicago sativa L.) on dry matter yield (DMY), forage nutritive value, and stands persistence. The objective of this study was to determine the effect of timing of a fall cut on DMY, forage nutritive value and stand persistence of three alfalfa varieties: low-lignin Hi-Gest 360, Roundup Ready Tonica, and conventional Gunner in Northeastern Kansas in the United States. The field study was carried out by splitting plot in randomized complete block design with four replications. The harvesting data of different maturity stages were collected in each year from 2015 to 2018. Three cuts were harvested based on the stage of maturity, and the last (fourth) cut was done on September 15, September 30, October 15, and October 30 of each year. The persistence of the alfalfa stands was determined each fall after the last cut, and each spring after the first cut, by counting the number of live plants in a randomly placed quadrat in each plot. Alfalfa cut on September 15 and September 30 had a higher stand persistence compared to alfalfa cut on October 15 and October 30. The DMY of the first cut in 2016 was significantly higher in roundup ready than the low-lignin alfalfa variety. In the second cut, DMY was significantly higher in conventional alfalfa than the roundup ready. There were no significant differences in DMY between alfalfa varieties in the rest of seasonal cuttings in 2016 and 2017 and annual total yield in both years. In general, low lignin alfalfa variety had higher crude protein and relative feed value and lower acid detergent fiber and neutral detergent fiber contents than those in roundup ready and conventional alfalfa varieties. On average, nutritive value of alfalfa was generally affected by last cutting dates in 2017. Based on 3-year data the last cutting of alfalfa in the fall could be done by September 30-October 15 without harmful effect on DMY.