• 한국기계가공학회지
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• 제3권4호
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• pp.13-19
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• 2004

This paper deals with the analysis of geometric error and the optimization of process parameters in surface grinding. Taguchi method which is one of the design of experiments has been introduced in achieving the aims. The process parameters were the grain size, the wheel speed, the depth of cut and the table speed. The effect of the process parameters on the geometric error was examined and an optimal set of the parameters was selected to minimize the geometric error within the controllable range of the used grinding machine. The reliability of the results was evaluated by the ANOVA.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.54-59
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• 2004

A measure for good products manufactured by grinding process is the surface roughness that is affected by a lot of operating parameters such as types of abrasive, grain size, bond material, wheel speed, table speed, depth of cut, hardness of workpiece and stiffness of grinding machine. In this study, an application of the design of experiments was tried for evaluating the effect of operating parameters on the surface roughness. The workpiece was a high speed tool steel(SKH51) and the surface grinding was conducted. In order to obtain the best surface roughness within constraints of the working range, the optimal grinding conditions were selected. The usefulness of this method was evaluated by the statistical strategy.

• 복식
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• 제20권
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• pp.49-62
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• 1993

The purpose of this research was to utilize of Pattern Design System(P.D.S) by using AM-300 The conclusion were like these : 1. A coat of basic pattern was selected by design sketch. 2. The basic pattern was input into computer by digitizing. 3. The basic pattern was change into designed shape by using various skills. This system were enabled to draw straight lines, curves, delete lines, sections of lines, extend lines, cut pattern into sections, measure line or section reproduce whole pattern shape of section, rotate and mirror pattern and complete patterns. 4. Automatic grading of finished master pattern have been developed by creation and modification of grading rules of basic pattern. 5. Production pattern added seam allowance, not-ches was generated by P.D.S menu option. 6. Finished pattern design was plotted out 100% and 20% size by AM-300 Plotter. This results will be the basic materials to develop the CAD SYSTEM if some problems were improve. Furthermore, the utilization of P.D.S is expected to be developing in pattern making process.

• 한국산업융합학회 논문집
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• 제23권1호
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• pp.101-106
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• 2020

Along with dust collection efficiency, pressure loss is a very important cyclone operation factor. A severe rise in pressure loss causes the problem of cost. To solve the problem, the method connecting axial-vane type cyclones in parallel is suggested recently. The axial vane type cyclone dust collector applied in this study is a small portable type. Multiple cyclones are installed in a round type. The basic performance test on the axial vane type cyclone dust collector was conducted. As a result, the cut size reduced along with a rise in the wind velocity of the cyclone dust collector inlet. According to the test on dust collection efficiency, the effect of dust collection began to appear in the range of 3㎛ and dust collection efficiency was greatly improved at 5 ㎛. The noise of the cyclone dust collector well met the fan sound power level of KSB 6361.

• 소성∙가공
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• 제17권2호
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• pp.107-112
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• 2008

In order to investigate the residual stress evolution during the leveling process of hot rolled high strength coils for cold forming, the in-plane residual stress of plate sampled at SPM, rough leveler and finish leveler were measured by cutting method. Residual stress was localized near the edge of plate. As the thickness of plate was increased, the size of residual stress region was expanded. The gradient of residual stress within the plate was reduced during the leveling process. But the residual stress itself was not removed completely within the ranges of tested conditions. The exact camber of cut plate was able to be predicted by the measurement of residual stress distribution after leveling of the plate.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 추계학술대회 논문집
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• pp.124-125
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• 1999

대기중에 부유하는 미세입자는 인체에 유해한 영향을 미칠 수 있어, 입자 포집 방법에 대한 관심이 높아지고 있다. 부유 에어로졸 입자중 $10\mu\textrm{m}$ 크기 이하의 미세입자는 인체의 흉관 부위까지 도달할 수 있다. 특히 약 $2.5\mu\textrm{m}$ 크기 이하의 입자는 폐포관에 침착할 가능성이 매우 커서, 입자의 화학조성, 침착 부위에 따라서 인체에 유해 정도가 달라질 수 있다. 최근에 미국 EPA에서는 부유분진 입자의 규제를 $2.5\mu\textrm{m}$ 이하입자의 질량 농도에 두고 있다.(중략)

• 한국연초학회지
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• 제19권1호
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• pp.70-75
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• 1997

The expansive properties of leaf tobacco by nitrogen gas was investigated with cut tobacco AB3O-1, CD3L-1(NC82). Major factors for the best expansion of the tobacco by the gas were an impregnated pressure and expansion temperature. The expansion rate for AB3O-1 and CD3L-1 at 250℃, 750kg/cm2 was 96.6%, 99.4% respectively. The shred size and fineness index at 96.6% of expansion rate for AB3O-1 was almost the same as at 58.3% for CD3L-1. The time reaching at equilibrium moisture under of RH 57% was 36hr in non-treated leaf tobacco, but it was 20hr in expanded tobacco. We confirmed that total sugar contents of leaf tobacco by the expansion was decreased with 9.3∼10.9%. Total alkaloid was decreased with 17.5∼21.1% and ether extracts was declined with 4.9∼9.3%. These results suggest that the expansion method of leaf tobacco by nitrogen gas is a useful method without any serious environmental troubles. Key words : expansion, nitrogen gas, heat treatment, tobacco.

• 대한수의학회지
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• 제32권1호
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• pp.111-115
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• 1992

A round, milkish white mass, approximately $4{\times}4{\times}5cm$ in size was found at the cranial part of the left kidney from a New Zealand White rabbit which was used as an untreated control animal in the safety evaluation test in the Toxicology Research Center, Korea Research Institute of Chemical Technology. The mass was lobulated and encapsulated. The cut surface revealed several round well-circumscribed lobules which were 0.5-3cm in diameter. No metastasis was observed. The microscopic features consisted of blastema and epithelial structures at variable stages of differentiation including primitive tubules, ducts, glomeruloid bodies. Normal mesenchymal cells were distributed among them. A diagnosis of nephroblastoma was made on the basis of the gross and microscopic features.

• 전자공학회논문지B
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• 제33B권10호
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• pp.12-19
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• 1996

Many recent supercomputers employ a kind of switch-based multistage interconnection network architectrues (MINs) for constructing scalabel parallel compters. This paper proposed a new routing method, hybrid wormhole and virtual-cut through routing (HWCR) for the prevention of rapid performance degradation comming from a conflict in links usage at hot traffic situation. This HWCR through (VCT) for the fast removing temporal stagger, result in seamless flow of packet stream. When the blocked link is removed, wormhole routing is resumed. The HWCR method adopted a hierachical buffer scheme for improving the network performance and reducing the cost in BMINs. We could get optimum buffer size and communicatin latency through the computer simulation based on proposed HWCR, and the results were compared to those using wormhole and VCT.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.340-347
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• 2003

The aim of regularization of a structural configuration is to obtain a structure that consists of elements with identical or nearly identical length. And it is also possible to modify the configuration in a manner that the size of the elements vary in accordance with a specified pattern. For practical purpose, geodesic dome is cut off at a suitable place in order to make it fit on horizontal. Inevitably this pattern effects a change of element lengths. The purpose of this study is to verify a method for regularization of structural configuration by genetic algorithms and modify the element lengths of the dome. As a result of regularization of domes with various rise-span ratio, modified configurations have more regular element lengths and are more economical than initial configurations.