• Communications of the Korean Mathematical Society
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• v.20 no.2
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• pp.365-379
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• 2005

The purpose of this paper is to correct erroneous proofs of theorems of He, Lu, Wang and Zheng [1] about the topological pressure of continuous flows without fixed points and to give proofs of some results which are stated in the literature without proofs and thereby to show that their theorems are still true.

• International Commerce and Information Review
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• v.8 no.3
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• pp.121-142
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• 2006

Recently regarding the ownership and proper operational forms of paperless trade infrastructure has become an issue. In this research the structural separation approach, different from the behavioral regulation approach, has been adopted. Following the structural separation, the core e-trade infrastructure which is separated from a vertically integrated provider, can be operated by three different forms such as a private sector; a public sector; finally a consortium among participants. As another option, the separated whole infrastructure including both core and non-core can be operated by a independent private entity. However, this option is not interesting case to us. As the last option, it can be considered that a new wholesale independent company for the separated core-infra can be set up for running. Additionally, three other alternative ways such as accounting separation, division separation, or corporation separation with keeping same ownership are also demonstrated. However the cautious investigation on cost and benefits of vertical separation are strongly recommended by OECD and agrees with the conclusion of this study.

• International Journal of Fluid Machinery and Systems
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• v.5 no.2
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• pp.49-59
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• 2012

The present study is devoted to the influence of a superposed radial inflow in a rotor-stator cavity with a peripheral opening. The flow regime is turbulent, the two boundary layers being separated by a core region. An original theoretical solution is obtained for the core region, explaining the reason why a weak radial inflow has no major influence near the periphery of the cavity but strongly affects the flow behavior near the axis. The validity of the theory is tested with the help of a new set of experimental data including the radial and tangential mean velocity components, as well as three components of the Reynolds stress tensor measured by hot-wire anemometry. The theoretical results are also in good agreement with numerical results obtained with the Fluent code and experimental data from the literature.

• Korean Journal Plant Pathology
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• v.13 no.1
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• pp.5-12
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• 1997

Genetic diversity of forty-four strains of Xanthomonas campestris pv. vesicatoria from diverse geographic origins was investigated using random amplified polymorphic DNA (RAPD) of genomic DNA. One hundred and thirty-seven amplified fragments were produced by polymerase chain reaction with a set of 14 random primers, and the sizes of amplified DNA fragments ranged approximately from 0.3 to 3.2 kb. Cluster analysis of genetic similarity among the strains generated the dendrogram that clearly separated all strains from each other. The 44 strains of X. campestris pv. vesicatoria were classified into 4 major genomic DNA RAPD groups and 15 subgroups at the genetic similarity of 0.60 and 0.92, respectively. The strains from foreign countries formed discrete subgroups, but the United States strain 87-77 clustered closely with some of Korean strains together. Thirty-nine Korean strains were classified into 11 subgroups, and especially Masan strain Ms93-1 clustered distinctly far from the other Korean strains. RAPD polymorphism suggests strongly the occurrence of genetic differentiation of X. campestris pv. vesicatoria and the existence of genetically distinctive subgroups among the populations in Korea.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.313-317
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• 2012

BACKGROUND: Citrus is usually propagated by grafting onto a rootstock. In Korea, As trifoliate orange (Poncirus trifoliata) has dwarf and strong cold hardness, it is widely used as the rootstock of satsuma mandarin. Because 'Shiranuhi' ((Citrus unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulata), a kind of citrus, also, generally is grafted onto a trifoliate orange, most of farmer has been recognized that 'Shiranuhi' root is naturally trifoliate orange. Meanwhile, reduction of flowering in 'Shiranuhi' orchard has been issued among the farmers and researchers over past few years and they guessed it was occurred by severe prune, oversupply of fertilization, overfruiting and temperature of growth period. However, a few researchers strongly assumed that it would be caused by scion rooting of 'Shiranuhi'. So, this study was carried out to identify the existence of scion rooting in 'Shiranuhi' tree in Korea. METHODS AND RESULTS: To identify the existence of scion rooting in 'Shiranuhi' tree, we randomly selected six 'Shiranuhi'orchards and we surveyed three to four trees, which flowering was not enough, from six 'Shiranuhi' orchards respectively. We took the root samples of 'Shiranuhi' mandarin, and then separated the two group which were non-scion rooting (Trifoliate orange), and scion rooting ('Shiranuhi' mandarin). To identity the scion rooting, we used primer set of three types which were a F2/R15, F4/R15 and F5/R15 primer set. As a result, when we conducted the DNA analysis, fourteen tree in less bloomed twenty tree was proved as tree with the scion rooting of 'Shiranuhi' mandarin. CONCLUSION(S): Scion roots of 'Shiranuhi'mandarin were usually observed in a deeply planted tree, and xylem of 'Shiranuhi' root indicated more white color than a case of trifoliata orange. 'Shiranuhi' tree by scion rooting was more vigorous but less flowering than trees grafted onto trifoliata orange. When we used F2/R15, F4/R15 and F5/R15 primer set for discriminance of 'Shiranuhi'mandarin root and trifoliate root, we identified the existence of scion rooting in 'Shiranuhi', From our results, it is suggested that the influence of scion root should be reviewed in 'Shiranuhi'orchards.