• 소음진동
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• 제3권2호
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• pp.163-167
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• 1993

Suction and discharge valves of special type refrigerant compressor are designed by finite element method for effective valve design development procedure. It is well known that valve dynamic characteristics, for example, the natural frequencies and vibration modes, are necessary for the computer simulation of compressor valve dynamics, the analysis of flow patterns, noise, impact stresses and their propagation phenomena. This paper has analysed the natural frequencies and vibration modes for the first three orders under the given special boundary conditions and the experiments are conducted by laser holography. And also stress distribution is analysed and experiment by strain gage is followed.

• 농촌계획
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• 제2권1호
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• pp.91-99
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• 1996

This study was accomplished to present a new paradigm of rural environmental planning for the purpose of changing a rural planner's acknowledgments. This study was composed of a follows, To search the structures and orders in rural environment on the point of four environmental contexts. First, environment contexts with spaces, society, and time. Second, environment contexts with spaces unit in human settlement. Third, environment contexts with correlation of physical environment, institutional environment, and social environment. Fourth, environment contexts with ecotope( physiotope + biotope) and landscape ecology. To analyze and criticize a present political situation of rural planning in Korea. To apply a paradigm of environmental planning for rural planning.

• Structural Engineering and Mechanics
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• 제3권4호
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• pp.383-390
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• 1995

A 2-D four-noded finite element which contains a ${\lambda}$ singularity is developed. The new element is compatible with quadratic standard isoparametric elements. The element is tested on two different examples. In the first example, an edge crack problem is analyzed using two different meshes and different integration orders. The second example is a crack perpendicular to the interface problem which is solved for different material properties and in turn different singularity order ${\lambda}$. The results of those examples illustrate the efficiency of the proposed element.

• Journal of Species Research
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• 제5권3호
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• pp.333-342
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• 2016

Based on the taxonomic survey to uncover the ciliate diversity in the eastern Kangwon-province, twenty-six species were identified from moss-covered soils and assigned to 5 classes, 9 orders, 12 families, and 15 genera. Of these, fifteen species are first records from Korea, and brief remarks with photographs were provided.

• Journal of Species Research
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• 제6권spc호
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• pp.15-25
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• 2017

Twelve ciliates were collected from freshwater, marine, and brackish water habitats in Korea and taxonomic descriptions are provided based on observations of living cells and protargol-impregnated specimens. These ciliates, recorded for the first time in Korea, were classified into 12 genera, 11 families, 10 orders, and five classes. We provide brief descriptions and remarks, including microphotographs, for the 12 ciliates: Allotricha mollis, Amphileptus eigneri, Didinium gargantua, Holophrya teres, Lacrymaria marina, Novistrombidium apsheronicum, Pelagostrobilidium conicum, Pseudochilodonopsis fluviatilis, Pseudourostyla subtropica, Strombidium conicum, Urocentrum turbo, and Uronema marinum.

• East Asian mathematical journal
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• 제21권2호
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• pp.191-203
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• 2005

In the present paper we first establish some basic results for a substantially more general class of functions defined below. The results include simple differentiation and fractional calculus operators(integration and differentiation of arbitrary orders) for this class of functions. These results are then invoked in determining similar properties for the generalized Wright's hypergeometric functions. Further, norm estimate of a certain class of integral operators whose kernel involves the generalized Wright's hypergeometric function, and its composition(and other related properties) with the fractional calculus operators are also investigated.

• Korean Journal of Mathematics
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• 제27권1호
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• pp.63-80
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• 2019

In this paper, we consider a special hypergroup defined by Corsini and we name it Corsini hypergroup. First, we investigate some of its properties and find a necessary and sufficient condition for the productional hypergroup of Corsini hypergroups to be a Corsini hypergroup. Next, we study its regular relations, fundamental group and complete parts. Finally, we characterize all Corsini hypergroups of orders two and three up to isomorphism.

• 한국정보통신학회논문지
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• 제13권12호
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• pp.2525-2532
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• 2009

본 논문에서는 uncoded V-BLAST(Vertical Bell Laboratories Layered Space Time) 시스템에서 PSK 신호들을 joint-detection하기 위한 fast sphere decoder를 제안한다. 이른바 PSD라 불리는 제안된 디코더는 예비처리단계와 검색단계로 구성된다. PSD의 검색단계에서는 depth-first branch and bound 알고리즘을 통해 검출 후보가 되는 신호원들의 최상우선순위(best-first order)를 정하고 이 순위에 따라 신호를 검출하게 된다. 이 때 제안된 디코더는 최상우선순위(best-first order)를 정하는데 있어 계산복잡성을 줄이는 새로운 방법을 제안한다. 시뮬레이션 결과는 PSD에 의해 시스템의 복잡성은 줄이면서 시스템 성능은 ML과 동일하게 유지할 수 있음을 보여준다.

• Animal Systematics, Evolution and Diversity
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• 제24권3호
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• pp.327-332
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• 2008

Soft coral Dendronephthya gigantea (Verrill, 1864) is a conspicuous species dominating shallow sea waters of Jejudo Island, Korea. Recently its whole mitochondrial genome sequencing was completed by us and the sequence information provided an opportunity to test the age of Octocorallia and time of evolutionary separation between some representative orders of the subclass Octocorallia. Molecular phylogenetic analyses based on 13 mitochondrial protein encoding genes revealed a polyphyletic relationship among octocorallians representing two orders (Alcyonacea and Gorgonacea) and four families (Alcyoniidae, Nephtheidae, Briareidae, and Gorgoniidae). Estimates of divergence times among octocorallians indicate that the first splitting might occur around end of or after Cretaceous period (50-79 million years ago (Ma)). The age is relatively young compared to the long history of stony sea corals (>240 Ma). Taken together our result suggests a possible relatively recent radiating evolution at least in the order Alcyonacea and Gorgonacea. Molecular dating and phylogenetic analysis based on much broader taxon sampling and many genes might give an insight into this interesting hypothesis.

• 경영과학
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• 제21권3호
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• pp.101-113
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• 2004

In the rapidly propagating Internet based electronic transaction environment. the importance of real time order confirmation has been more emphasized, In this paper, using data mining techniques, we develop intelligent operations decision model to allow real time order confirmation at the time the customer places an order with required delivery terms. Among various operation plannings used for order fulfillment. mill routing is the first interface decision point to link the order receiving at the marketing with the production planning for order fulfillment. Though linear programming based mathematical optimization techniques are mostly used for mill routing problems, some early orders should wait until sufficient orders are gathered for optimization. And that could effect longer order fulfillment lead-time, and prevent instant order confirmation of delivery terms. To cope with this problem, we provide the intelligent decision model to allow instant order based mill routing decisions. Data mining techniques of decision trees and neural networks. which are more popular in marketing and financial applications, are used to develop the model. Through diverse computational trials with the industrial data from the steel company. we have reported that the performance of the proposed approach is effective compared to the present heuristic only mill routing results. Various issues of data mining techniques application to the mill routing problems having linear programming characteristics are also discussed.