• Honam Mathematical Journal
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• v.2 no.1
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• pp.13-18
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• 1980

모든 기호(記號)는 G.E Bredon의 저(著) Sheaf Theory의 기호(記號)를 따른다. A가 torsion free이며 elementary sheaf이라 하자. 그리고 L을 injective L-module이라 하자 $dim_{\varphi}X<{\infty}$이라면 support의 $family{\varphi}$와 locally subset z에 대하여 ${\Gamma}_{z}(^{\sim}Hom({\Gamma}_{\varphi}(L),L){\otimes}A){\simeq}H_0{^{z}}(X:A)\;H_{-p}{^{z}}(X:A)=0,\;p=1,2,3,$⋯⋯ 이며 support의 family c와 compact subset z에 대하여도 ${\Gamma}_{z}(^{\sim}Hom({\Gamma}_{c}(L),L){\otimes}A){\simeq}H_0{^{z}}(X:A)\;H_{-y}{^{z}}(X:A)=0,\;p=1,2,3,$⋯⋯ A가 elementary이면 locally closed z와 z에서 closed인 $z^{\prime}$ 그리고 $z^{\prime\prime}=z-z^{\prime}$에 대하여 exact sequence ⋯⋯${\rightarrow}H^{z^{\prime}}_{p}\;(X:A){\rightarrow}H^{z}_{p}(X:A){\rightarrow}H^{z^{\prime\prime}}_{p}\;(X:A){\rightarrow}$⋯⋯ 가 존재(存在)한다.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.133-136
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• 1996

The nozzle dam task is essentially needed to maintain and repair nuclear power plants. For this task, an 8-dof redundant robot is studied with a local path-planning method[l] which is effective to find the optimal joint path in the constrained environment. In this paper, the method[l] is improved practically with the weight matrix and efficient algorithm to find working set. The effectiveness of the proposed method is demonstrated by simulation and animation.

• Journal of Powder Materials
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• v.5 no.4
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• pp.258-264
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• 1998

The initial sintering behaviour of the powder injection molded (PIMed) W-l5wt%Cu nanocomposite powder was investigated. The W-Cu nanocomposite powder was produced by the mechanochemical process consisting of high energy ball-milling and hydrogen reduction of W blue powder-CuO mixture. Solid state sintering of the powder compacts was conducted at $1050^{\circ}C$ for 2~10 hours in hydrogen at mosphere. The sintering behaviour was examined and discussed in terms of microstructural developments such as W-Cu aggregate formation, pore size distribution and W grain growth. The volume shrinkage of PIM specimen was slightly larger than that of PM(conventional PM specimen), being due to fast local densification in the PIM. Remarkable decrease of carbon and oxygen in the PIM enhanced local densification in the early stage of solid state sintering process with eliminating very fine pores less than 10 nm. In addition, such local densiflcation in the PIM is presumably responsible for mitigating of W-grain growth in the initial stage.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.209-214
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• 1995

This paper describes that the effects of punch speed and temperatures of the die and the blank holder on the drawability are examined. Up to now, multi-stage of dies sets have been used generally at room temperature in deep drawing of rectangular shaped components. But using local heating, it is shown that one stage of die set was capable of deep drawing and the drawability was increased and sheet thickness of component was drawn somewhat uniformly. Rectangular deep drawing experiments on two kinds of stainless steel STS316L, STS430 of 1.0 mm thickness have been conducted using local heating. The limiting drawing height can be increased by heating the die and the blank holder up to 100 .deg. C at STS316L. Commercial lubricants hadn't an effect on drawability in rectangular deep drawing, but vinyl and teflon film had an effect on it.

• International Commerce and Information Review
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• v.15 no.1
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• pp.357-379
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• 2013

Recently, the government was introduced as currency for earning of raw materials purchasing system for electronic Government management of foreign trade in 2011, and revised regulations for electronic proof of purchase. In addition, the currency for earning of raw materials, such as procurement system in 2012, followed by electronic proof of purchase local letter of credit. The government electronic trading will be promoting local trading of electronic procedures. This study will be a preceding research on the goods control system for acquiring foreign currency and the obligation of using digitalized approval of purchase due to the revision of foreign trade law. Also, it will conduct theoretical and legal research regarding the obligation of digital establishment of the local L/C which is a result of amendments to the rules of operation for the Bank of Korea's trade finance. Further, it will analyze the legal and operational problems and its response plans for the establishment of the local trade integrated management system which promotes the digitalization of the local trade process.

• Journal of Welding and Joining
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• v.10 no.2
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• pp.51-62
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• 1992

A torch was designed and fabricated in order to develope the technology of "locally drying underwater welding" by water curtain method. The condition for the formation of the possible local cavity, the mechanical properties and the thermal cycle of welds were investigated in the developed welding equipment compared with in-air welding. The possibility of highly reliable and practical underwater welding was found. The proper local cavity was formed above the water flowrate of 30l/min and CO$_{2}$ gas flowrate of 100l/min. The bead width and penetration depth were increased with increasing welding current. The hardness of weldments is about 160Hv in air welding, but about 210Hv in underwater welding. The elongation and the impact value of underwater weldments are 15% and 6Kg/cm$^{2}$ respectively, which are only half as much as the values of in-air welding. The cooling time in the temperature range from 800.deg.C to 500.deg.C affecting the structure and the hardness of weldments is about 22sec. in air welding while about 10sec. in underwater welding.r welding.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.1 no.3
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• pp.244-251
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• 1989

A numerical study has been performed on the natural convection heat transfer from a conducting tube with two axial fins to a surrounding cylinder. As increasing dimensionless fin length ($L_F$), the center of flow moves to the bottom of annulus and the recirculating flow rate is decreased. The maximum local Nusselt number of conducting tube appears at ${\theta}=180^{\circ}$ for $L_F=0.0$, but at ${\theta}=130^{\circ}$ for $L_F{\geq}0.3$ and that of outer cylinder appears at ${\theta}=13^{\circ}$ for $L_F{\leq}0.6$ but at ${\theta}=33^{\circ}$ for $L_F=1.0$. The fin temperature is decreased by increasing radial distance and the temperature distribution of the downward fin is generally less than that of the upward fin. By increasing fin length, the local Nusselt number of the upward fin appears negative values for $L_F=1.0$, but appears positive values for $L_F<0.8$, and that of the downward fin appears positive values.

• Archives of Pharmacal Research
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• v.12 no.2
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• pp.63-67
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• 1989

The various esters of 20R and 20S-dihydroprednisolonic acid were prepared and evaluated for their local and topical anti-inflammatory activities in rats, including systemic effects. It was demonstrated that the size of the substituent at C-21 and configurational arrangement at C-20 have significant effects on local and topical activity. It was also found that all the derivatives did not show systemic effects as accessed by thymus weight and adrenal weight at the dose level used, while prednisolone showed profound effects on thymus weight.

• Journal of Environmental Science International
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• v.9 no.2
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• pp.101-108
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• 2000

Through numerical experiment using simplified OSU-1D PBL(Oregon State University One-Dimensional Planetary Boundary Layer) model and field measurement, we studied the impacts of vegetation canopy on heat island that was one of the characteristics of local climaate in urban area. it was found that if the fraction of vegetation was extended by 10 percent, the maximum air temperature and the maximum ground temperature can come down about 0.9${\circ}C$, 2.3${\circ}C$, respectively. Even though the field measurement was done under a little unstable atmospheric condition, the canopy air temperature was lower in the daytime, and higher at night than the air and ground temperature. This result suggests that the extention of vegetation canopy can bring about more pleasant local climate by causing the oasis, the shade and the blanket effect.

• Bulletin of the Korean Mathematical Society
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• v.43 no.4
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• pp.723-735
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• 2006

In [2] it was shown that a 1-generator quasi-cyclic code C of length n = ml of index l over $\mathbb{Z}_4$ is free if C is generated by a polynomial which divides $X^m-1$. In this paper, we prove that a necessary and sufficient condition for a cyclic code over $\mathbb{Z}_pk$ of length m to be free is that it is generated by a polynomial which divides $X^m-1$. We also show that this can be extended to finite local rings with a principal maximal ideal.