• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.775-784
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• 2008

It is not easy to access very high speed Internet services at sea due to some technical and economical problems. In order to realize the very high speed Internet services at sea like on land, new communication network models based on MANET should be adopted. In this paper, a new MANET model at sea is provided, which considered the ocean environments, and the characteristics and movement of vessels. On the basis of the fact that most vessels navigate on the predetermined courses, which are the shortest paths between source and destination ports in most cases, a type of location oriented routing protocol is proposed in this paper. The Hybrid Course-Based Routing Protocol(HCBR) makes use of the static information such as courses and positions of ports to proactively find the shortest paths not only among ports but also the cross points of courses. HCBR also makes use of the locational information of vessels obtained via GPS and AIS systems to reactively discover the shortest route by which data packets are delivered between them. We have simulated the comparison of the performance of HCBR with those of LAR scheme 1 and scheme2, the most typical protocols using geographical information. The simulation results show that HCBR guarantees the route discovery even without using any control packet. They also show that HCBR is more reliable(40%) and is able to obtain more optimal routes(10%) than LAR scheme1 and scheme2 protocols.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.307-316
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• 1994

To investigate the effect of light pretreatment on photosynthetic characteristics of leaf blade of rice, 2 varieties of japonica type and 2 varieties of tongil type were grown under 30% or 70% shading conditions from tillering stage to heading stage. Shading treatment of 70% at the heading stage produced low dry matter, and higher LAR and SLA compared with other combination of shading treatment and growing stage did. Photosynthetic activity was lower in order of 0%, 30% and 70% shading treatment under the low light intensity(5Klux) but significantly high in 30% shading treatment under the high light intensity (33Klux) at tillering stage. Photosynthetic activity under low(5Klux) and high(33Kluk) light intensity were higher in order of 70%, 30% and 0% shading treatment at heading stage. Respiration /photosynthesis ratio was lower in shading treatment than in control. CGR, RGR and NAR decreased in shading treatment. Shading treatment reduced the number of ripened grain per panicle and decreased the harvesting index.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.619-628
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• 1995

Crude aqueous extracts from dried leaves, stems, roots, and flowers from both field grown and greenhouse grown alfalfa plants inhibited alfalfa seed germination and seedling growth. The degree of inhibition was greater in the field grown plant extracts. Flowers extract of field grown plant most inhibited alfalfa germination and seedling growth. In the concentration study, the highest concentration of extract (9.0%, w/v) significantly inhibited total alfalfa seed germination by 50% as compared to control. In partitioning study using pot hydroponic culture of plant biomass into leaves, stems, root, LAR products of LWR and SLA exhibited significant variation among four species. This result support that the inhibitory effect of autotoxic substances presenting in alfalfa tissue may be possible interference with the patitioning of biomass into leaf component relative to the total biomass produced by the alfalfa plant. Toxicity of extract was not reduced by adding activated charcoal, Dowex-50W, amberlite to the extract. Toxic substances existing in most plant tissues but mainly above ground foliage are water soluble and stable and may persist in old alfalfa fields. Thus, it is recommended to remove as much as possible of the above growth parts, especially vegetative stage, before one tries to re-establish alfalfa in former field of alfalfa.

• Korean Journal of Medicinal Crop Science
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• v.8 no.4
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• pp.362-372
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• 2000

This study was conducted to obtain the basic information on the production of high yield and qualitied yam in Andong, major yam-producing district, in Kyongbuk province, using three major Yam cultivars, such as Danma, Jangma and Alata (round type). Alata showed the longest tuber width while Jangma showed the longest tube length. Danma showed the highest tube yield at 2,123 kg/10a. Tubes of Alata had higher dry ratio than those of other cultivars, suggesting that Alata could be used as good processing materials. Characteristics of top parts, such as vine length, leaf number, and lateral vine number showed typical sigmoid curves. Tuber characteristics such as length, width and fresh weight of tuber were linearly increased as the growth period was progressed. Relative growth rate (RGR) for new tuber and stem reached the highest value at 86 DAT (days after transplanting). There were similar tendencies among the cultivars in net assimilation rate (NAR). The highest crop growth rate (CGR) was appeared at 156 DAT regardless of cultivars. In the changes of leaf area ratio (LAR), there were significant differences among three cultivars. LAR were decreased at 86, 106 and 136 DAT for Alata, Danma and Jangma, respectively. However, specific leaf weight (SLW) was greatly increased at 176 DAT, and leaf area index (LAI) was decreased at 156 DAT in all cultivars.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.228-234
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• 1996

The rates of solvolysis of 1-(4-methoxyphenyl)-1-aryl-2,2,2-trifluoroethyl chlorides[I] in a variety of solvents were measured by an electroconductometric method. LArSR relationships (Yukawa-Tsuno eq.)were found to give a linear plot, log(k/ko)=-1.84[σo+0.918(σ+-σo)], in 80% aqueous ethanol. Small |ρ| and r values in comparison with 1-aryl-1-(trifluoromethyl)ethyl tosylate(ρ=-6.09, r=1.59) suggested that the carbocationic charge in the transition state was dispersed by a strong p-π donor, p-methoxy group. Linear mY plots with m 0.90 for all of the substituents in aqueous acetone and m=0.60-0.82 for those of aqueous ethanol indicate that this solvolysis proceeds via an SN1 mechanism with nucleophilic solvent assistance. Thiourea effects and isokinetic temperatures for the rate of solvolysis also can prove the above mechanism.

• Mycobiology
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• v.31 no.2
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• pp.81-85
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• 2003

Antifungal properties of methyl 2-benzimidazole carbamate(BMC) were investigated using 16 fungi. Cytotoxicity test of BMC revealed that the morphology of HeLa cells was considerably deformed even at the concentrations as low as 0.1 ppm. Minimum inhibitory concentration(MIC) values of BMC for 7 fungi among the 16 tested ones were lower than $1.95{\times}10^{-4}{\mu}g/ml$, while Aspergillus flavus showed an MIC value higher than 1.0 ${\mu}g/ml$. Tolerance induction against BMC was successful only for Paecilomyces farinosus LAR10, contrary to the expectation that tolerance would be induced for the fungi having high MIC values such as Aspergillus niger ATCC 9642 and A. flavus ATCC 9643. Spore germination of A. niger ATCC 9642 was suppressed by BMC. However the mycelial growth of the fungus once germinated was not retarded at all by BMC up to 8 MIC. Addition of lanosterol provided a remedy for the reduced germination rate of A. niger ATCC 9642 spores.

• Journal of Oral Medicine and Pain
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• v.8 no.1
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• pp.77-82
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• 1983

The author measured the degree of alveolar bone resorption around mandibular central incisors in Korean female(254). Mandibulr central incisors were selected from the females who do not have periodontal disease or malocclusion. The selected radiograms were enlarged in the $5"\times7"$ printing papers for the precise measuring. The obtained results were as follows : 1. The average alveolar bone resorption around mandibular central incisors in Korean women were 1.91mm in 3rd decade, 2, 16mm in 4th decade, 2.51mm in 5th deacade, 2.70mm in 6th decade, 2.94mm in older age group. 2. Alveolar bone resorption and age were in positive correlation; there is a tendency that the alveolar bone resorption increase with aging. 3. The regression equation is as follows. Y=13.57x + 7.06(r=0.60, n=254) (Y=estimated age, x=Length(C-E Junction alveolar crest)lar crest)

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.604-609
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• 1995

The relative dissociation constants of 4-substituted bicyclo[2,2,2]octane-1-carboxylic acids, 4-substituted quinuclidines, and 3-and 4-substituted pyridines were collected from a number of sources. In order to understand the actual substituent effects with a combination of inductive effect (σI) and resonance effect (σR) components. The DSP correlation has been employed statistically for each of the p-and m-series. The inductive effect from the m-position was 1.2 times more effective than that from the p-position and the requirement of σR+ for the best-fit led to the conclusion that pyridine system belongs to the σ+-class reactivity. Also compared with results from Yukawa-Tsuno's LArSR treatment and relevant treatment.

• Journal of radiological science and technology
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• v.33 no.3
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• pp.213-221
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• 2010

The Purpose of this study was to determine the effective dose to an average patient from Coronary Angiography (CA) and Percutaneous Coronary Intervention (PCI). And to estimate the lifetime attributable risk (LAR) of cancer associated with radiation exposure from CA and PCI. The dose-area product (DAP) values to the patient were recorded from 60 CA and 58 PCI. A Monte Carlo based program PCXMC was used to calculate the effective dose from DAP values for each patient. Lifetime attributable risks were estimated with models developed in the National Academies' Biological Effects of Ionizing Radiation VII report. The mean DAP values was $53.76\;Gy{\cdot}cm^2$ for CA and $165.82\;Gy{\cdot}cm^2$ for PCI. Mean effective dose were 1.28 mSv in CA, 3.94 mSv in PCI. Results of Calculate organ dose, lung doses was 2.17 mSv in CA and 6.71 mSv in PCI. Female breast doses was 5.45 mSv in CA and 16.82 mSv in PCI. LAR estimates for CA varied from 1 in 1,508 for man to 1 in 1,357 for women. In PCI procedure varied from 1 in 553 for man to 1 in 482 for women. DAP can be used as the dose indicator to calculate the organ dose and effective dose of patient based on Monte Carlo simulation. These dose estimates derived from our simulation models suggest that CA and PCI are associated with a nonnegligible LAR of cancer. This risk varies markedly and is considerably greater for women, PCI than for man, CA.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.670-670
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• 2013

The concept of a fusion-driven transmutation reactor based on LAR (Low Aspect Ratio) tokamak as a neutron source is studied based on ITER physics and technology. The radial build of transmutation reactor components are self-consistently determined by coupling the systems analysis with radiation transport analysis and an optimal configuration of a transmutation reactor for aspect ratio, A in the range of 1.5 to 2.0 is found. The performance of a transmutation reactor is investigated and shows that a transmutation reactor with a neutron source producing fusion power less than 150 MW can destroy the transuranic actinides contained in the spent fuels produced from more than two 1 GWe PWRs with production of the fission power being greater than 2 GW.