• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.788-801
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• 1998

Meteor Burst Communication can provide effective and economical means of communication where long distance VHF NLOS data transmission is needed ; often ranges more than 1000 km. It has been, however, so far considered unsuitable for short distance application because of phenomenal decrease in burst durations, which leads to decreation of total duty rate of the system. This paper extensively analyzes characteristics of shot distance MB(Meteor Burst) path and shows the low duty rate may be improved by increasing burst rate through adapting antennal beam width to cover entire hot-spot region in the space and, by compensating effective burst length throughcutting down man-made noises introduced by antennal. Based on the analysis, we are developed a small-opening-cavity antennal, especially designed for short distance MB path. In operation, the antenna is to be buried under ground surface so as to improve directivity and reduces noise introduction. The antennal exhibits power gain of 3 dB with 90 degree beam width and thus enables to illuminate entire hot-spot regions with the elevation angle of 8-90 degree which is the case of transmission less than 100 km. Directivity horizontal to earth surface is suppressed to minimum which enables to cut man-made noises from near-by sources down to more than 3 dB from the level reported with conventional 4 element Yagi. A series of experiments performed on 100km MB paths have conformed that, with the antenna installed at receiving site, the burst rate and duration time have been noticed to increase by 10 and 20 percent respectively from the values obtained by conventional 4-element Yagi antennal under same testing condition.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.246-251
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• 2006

A lot of mutants which cannot initiate sexual development were screened and several loci including nsdA, nsdB, nsdC, and nsdD were identified in homothallic ascomycetes Aspergillus nidulans. The NSD206, which has nsdC6 allele, showed typical phenotype of NSD (Never in sexual development) mutants. The nsdC gene was cloned by transforming NSDP697 ($nsdC^-$, $pryG^-$) with AMA1-NotI genomic library. The transforming library DNA recovered from several transformants showing wild phenotype carried about 10 kb genomic DNA insert. The DNA sequence of nsdC was analysed using GPS (Genome priming system). The nsdC gene has an open reading frame (ORF) of 1,929 bp encoding a putative polypeptide of 643 amino acids. The NsdC carries $C_2H_2C_2H_2C_2HC$ type zinc finger DNA binding domains in the middle of the polypeptide. A coiled-coil domain at its C terminus were also found. In nsdC6 allele, a single T insertion was occurred between 407-408 bp leading to the frameshift mutation and early termination of translation producing the truncated protein which has only 139 amino acids.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.147-154
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• 1999

This research was carried out to obtain the field resistance to disease and pest, and high yielding of new Boxthorn (Lycium chinense Mill.) varieties. Growth characteristics, yield potential, correlation of trait which was related the yield and path coefficient of the domestic native varieties. two of cultivated varieties and four of introduced varieties were investigated. In growth characters of collected varieties, the stem length of collected varieties in China were slightly long. Leaf area in Jindo, Kumsan native and Yusong 1 and 2 were wider than that of other varieties. Resistance to pest iniury was very strong at China 1, Japan 1 and Yusong 2 in eriophyidmite, and also resistance to anthrax anthracnose were showed less than 10% of the rate of attack fruit at Japan 1 and China 1. Flowering stage was more early in Chungyang native than that of other varieties. Fruit size of Kumsan native, Yusong 2 were large size fruit varieties. Fruit setting number was most abundant at 1,623 in Yusong 2 which was collected variety. And dry yields of fruit per lOa was more cmparatively abundant in Yusong 2 at 86% than those of Chungyang native. The high correlation cofficienct character with fruit yield were fruit setting and branching number and leaf area. Direct effect by path anaslysis were fruit setting number (Py=0.45), and branching number was showed indirect effect.

• Journal of the Geological Society of Korea
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• v.54 no.5
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• pp.477-488
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• 2018

Fluid muds commonly occur in estuarine environments, but their ancient examples have rarely been studied in terms of depositional characteristics and processes. Cores of estuarine channel deposits of the Early Cretaceous McMurray Formation, Alberta, Canada show various mudstone layers that possess depositional characteristics of high clay-concentration flows. These mudstone layers are examined in detail through microscopic observation of thin sections and classified into three microfacies (<1 to 25 mm thick) on the basis of sedimentary texture and structures. Structureless mudstone (Microfacies 1) consists mainly of clay particles and contains randomly dispersed coarser grains (coarse silt to fine sand). This microfacies is interpreted as being deposited by cohesive mud flows, i.e., fluid muds, which possessed sufficient strength to support suspended coarser grains (quasi-laminar plug flow). Silt-streaked mudstone (Microfacies 2) mainly comprises mudstone with dispersed coarse grains and includes very thin, discontinuous silt streaks of coarse-silt to very-fine-sand grains. The texture similar to Microfacies 1 indicates that Microfacies 2 was also deposited by cohesive fluid muds. The silt streaks are, however, suggestive of the presence of intermittent weak turbulence under the plug (upper transitional plug flow). Heterolithic laminated mudstone (Microfacies 3) is characterized by alternation of relatively thick silt laminae and much thinner clay laminae. It is either parallel-laminated or low-angle cross-laminated, occasionally showing low-amplitude ripple forms. The heterolithic laminae are interpreted as the results of shear sorting in the basal turbulent zone under a cohesive plug. They may represent low-amplitude bed-waves formed under lower transitional plug flows. These three microfacies reflect a range of flow phases of fluid muds, which change with flow velocities and suspended mud concentrations. The results of this study provide important knowledge to recognize fluid-mud deposits in ancient sequences and to better understand depositional processes of mudstones.

• Journal of Korea Foundry Society
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• v.12 no.4
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• pp.293-297
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• 1992

• Proceedings of the Korean Magnestics Society Conference
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• 1998.05a
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• pp.112-113
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• 1998

• Proceedings of the Korean Magnestics Society Conference
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• 1998.05a
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• pp.24-25
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• 1998

• Proceedings of the Korean Magnestics Society Conference
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• 2006.06a
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• pp.127-127
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• 2006

• The monthly packaging world
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• s.94
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• pp.127-133
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• 2001

• The Korean Nurse
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• v.12 no.2 s.64
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• pp.62-65
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• 1973