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        검색결과 9,514

        8121.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        e-Navigation strategy IMO promotes is defined as it is necessary for network and information standard to provide various maritime safety informations to in land and on board users, and it is expected to provide a large amount and diverse kinds of maritime spatial information services to them. However, as there are some limits to transmit that by current mobile maritime communication technologies, it is required to simplify and optimize the information. In this study, tree node method is applied to ENC using Douglas-Peucker algorithm and we arranged the effect of simplified spatial information through CALS method which compensates the defect of basic tree node method.
        8122.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        This study is concerned with the applicable countermeasures for securing safety of ship from piracy attacks. For improvements and countermeasures, we analyzed the recent anti-piracy trends. In spite of international community's various activities for safety navigating, the number of piracy in Gulf of Aden and in the vicinity of Somali waters has been increasing dramatically in the last few years, so has the number of piracy on Korean vessels. In case of piracy attack which based on Somalia, it continues constantly and widely not only near shore, but coastal and oceanic waters. This study figures out the limitations of international community's efforts including military and legal improvements. There are no studies concerning the countermeasures of bridge protection by piracy. This study suggested the additional installation of outside door of bridge as well as the adjustment of piracy operation area(POA) of Korea navy.
        8123.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        Rumen fermentative characteristic is useful indicators of the quality of ruminant feed stuffs and diets. An in vitro rumen fermentation experiment was therefore carried out to compare fermentation patterns among three forage sources. These were whole crop barley (WCBS), Italian ryegrass silage (IRGS) and rice straw silages (RSS). Rice straw (RS) was the control, making the treatments 4 in total. Forages were randomly allocated to serum bottles. The incubation times were arranged 0, 3, 6, 9, 12, 24, 48 and 72h at 39℃, respectively. Each forage source was replicated 3 times per incubation time. At each sampling time, total gas and pH were measured, whilst individual volatile fatty acids (VFAs), total volatile fatty acids (TVFAs) and ammonia nitrogen (NH3-N) were determined later after storing samples at -20℃. Acetate: Propionate ratio (A/P) was then calculated. Forage source had a significant effect (P
        8124.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        ~gamma -Aminobutyric acid (GABA) is a non-protein amino acid that is widely distributed in plant and animal kingdom. GABA is found in tissues of the central nervous system (CNS) in animals. GABA functions as a the major inhibitory neurotransmitter in the CNS by acting through the GABA receptors. Clinical studies have revealed the relationship between an increased intake of GABA or analogues with several health benefits, including lowering of blood pressure in mildly hypertensive animals and humans. Furthermore, GABA would also has an inhibitory effect on cancer cell proliferation, stimulates cancer cell apoptosis and plays a role in alcohol-associated diseases and schizophrenia. In plants, interest in the GABA emerged mainly from experimental observations that GABA is largely and rapidly produced in large amounts in response to biotic and abiotic stresses. In this study, we speculated the properties and metabolism of GABA in plant and functions in relation to the responses to environmental stresses.
        8125.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        For QTL analysis of agronomic traits based on cultivation of low and high altitude locations, BC1 F5 181 lines were developed from a cross of Tongil type Gayabyeo and japonica Chhomrong originated from Nepal. Plant materials were grown in both of low altitude area of Milyang, Korea and high altitude area of Khumaltar, Nepal. In QTLs analysis, a total of 42 QTLs were detected in days to flowering, culm length, panicle length, number of panicles/hill, panicle exertion, and spikelet ripening ratio. Although many of the QTLs were coincided between the two locations of Korea and Nepal, several QTLs were revealed as location specific in high altitude area of Khumaltar. Especially, the regions harboring marker RM489-RM14281 on chromo- some 3, RM5642-RM19049 on chromosome 5, and RM2854-RM6696 on chromosome 12 where QTLs were clustered and coincided between the two locations are considered as positive target regions for environmental independent traits. Furthermore, high rate of location specific QTLs such as panicle exertion and spikelet ripening ratio could be considered carefully for understanding the mechanism of cold tolerance based on cultivation of different altitude location.
        8126.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        Resumptive pronouns in English are found in relative constructions where gaps are supposed to take the place. If a construction has two or more forms in free variation from the point of view of truth-conditional semantics, it is worthwhile investigating whether there are pragmatic differences. Based on Prince (1990, 1995)’s observations, we will show the pragmatic meaning difference between the gap-containing structure and the pronoun-containing structure. We will also show that the reconstruction based on movement theory does not suffice to explain the distribution. Then we will suggest that resumption is the last resort strategy at PF which needs reference-set computation against the suggestion of Aoun, Choueiri & Hornstein (2001) which is based on Binding. In the following chapter, many instances of resumptive pronouns will be presented, showing that there is not insignificant meaning difference between the gap-containing structure and the pronoun-containing structure. In chapter 2, the proposals of reconstruction will be critically surveyed. In chapter 3, the resumption as the last resort strategy will be suggested. Chapter 4 concludes the paper.
        8127.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        The marine carotenoid fucoxanthin can be found in marine brown seaweeds, macroalgae, diatoms, and microalgae, and has remarkable biological properties. Numerous studies have shown that fucoxanthin has considerable potential and promising applications in human health, but the underlying mechanisms involved in its anti-allergic activity are not fully understood. We here investigated the mechanisms by anti-allergic activity of fucoxanthin fraction from Eisenia bicyclis in immunoglobulin E-antigen complex (IgE/DNP-BSA)-stimulated RBL-2H3 mast cells. This study we found that the fucoxanthin inhibits the release of β-hexosaminidase and suppressed not only transcriptional activation of NF-kB, but also phosphorylation of ERK and JNK in IgE/DNP-BSA-treated RBL-2H3 cells. Fucoxanthin may be useful for preventing allergic diseases, including asthma and atopic dermatitis.
        8128.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        In this study we investigated the effects of supplementation with fucoidan from brown alga on the function of natural-killer (NK) cells to evaluate the possibility as an immunomodulator in ovariectomized (OVX) rats. A total of 18 female Wistar rats (six weeks) were used this study and 12 rats were OVX, and the rest of rats were sham-operated. The sham and one OVX group were fed standard diet, and the remaining OVX group received fucoidan (0.05% supplemented diet). After 12 weeks of supplementation, rats were sacrificed to assess the tumoricidal activity of the NK cells and the NO-iNOS regulation from splenocytes. The mass of body and the immune organs such as spleen and thymus were also studied. In OVX rats, body and thymus weights increased, however fucoidan supplementation did not change the body mass and organs weight compared to OVX group. Fucoidan supplementation increased NK cell activity and reduced NO-iNOS production in OVX rats. Ex vivo treatment of fucoidan increased NK cell activity in splenocytes from shame and OVX rats. Ex vivo, we confirmed that fucoidan partially reduced the NK cell activity in the presence of iNOS inhibitors in OVX-splenocytes. These results indicate fucoidan supplementation has a NK cell tumoricidal activity, which are regulated by the iNOS production in OVX rats. This suggests that fucoidan is useful for potential therapeutic strategies as a nutrient in regulating the NK cells in postmenopausal osteoporosis patients.
        8129.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The Korea Astronomy and Space Science Institute and the Department of Astronomy at the University of Texas at Austin are developing a near infrared wide-band high resolution spectrograph, immersion grating infrared spectrometer (IGRINS). The compact white-pupil design of the instrument optics uses seven cryogenic mirrors, including three aspherical off-axis collimators and four flat fold mirrors. In this study, we introduce the optomechanical mount designs of three off-axis collimating mirrors and one flat slit-viewer fold mirror. Two of the off-axis collimators are serving as H and K-band pupil transfer mirrors, and are designed as system alignment compensators in combination with the H2RG focal plane array detectors in each channel. For this reason, the mount designs include tip-tilt and parallel translation adjustment mechanisms to properly perform the precision alignment function. This means that the off-axis mirrors’ optomechanical mount designs are among the most sensitive tasks in all IGRINS system hardware. The other flat fold mirror is designed within its very limitedly allowed work space. This slit-viewer fold mirror is mounted with its own version of the six-point kinematic optics mount. The design work consists of a computer-aided 3D modeling and finite element analysis (FEA) technique to optimize the structural stability and the thermal behavior of the mount models. From the structural and thermal FEA studies, we conclude that the four IGRINS mirror mounts are well designed to meet all optical stability tolerances and system thermal requirements.
        8130.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The world’s first geostationary ocean color imager (GOCI) is a three-mirror anastigmat optical system 140 mm in diameter. Designed for 500 m ground sampling distance, this paper deals with on-orbit modulation transfer function (MTF)measurement and analysis for GOCI. First, the knife-edge and point source methods were applied to the 8th band (865 nm) image measured April 5th, 2011. The target details used are the coastlines of the Korean peninsula and of Japan, and an island 400 meters in diameter. The resulting MTFs are 0.35 and 0.34 for the Korean East Coastline and Japanese West Coastline edge targets, respectively, and 0.38 for the island target. The daily and seasonal MTF variations at the Nyquist frequency were also checked, and the result is 0.32 ± 0.04 on average. From these results, we confirm that the GOCI on-orbit MTF performance satisfies the design requirements of 0.32 for 865 nm wavelength.
        8131.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        We presented fundamental stellar parameters and evolutionary statuses of six solar type detached eclipsing binaries whose masses are in the range of 0.97-1.43 M⊙. EK Cep and FL Lyr belong to the zero age main sequence. HS Hya, IT Cas and CD Tau are on the main sequence. Their ages are 1.3, 1.9 and 2.2 Gyr, respectively. Both component stars of AI Phe evolved to sub giants and its age is 4.0 Gyr. Those ages of the detached binary systems show good agreement with the time scale for synchronization and circularization of the binary systems.
        8132.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspot data obtained in 1,965 days. The correction factor Kb for the entire observing period is 0.9519, which is calculated using the linear least square method to the relationship between the daily sunspot number, RB, and the daily international relative sunspot number, Ri. The yearly correction factor calculated for each year varies slightly from year to year and shows a trend to change along the solar cycle. The correction factor is larger during the solar maxima and smaller during the solar minima in general. This implies that the discrepancy between a relative sunspot number, R, and the daily international relative sunspot number, Ri, can be reduced by using a yearly correction factor. From 2002 to 2008 in solar cycle 23, 35.4% and 64.6% of sunspot groups and 35.1% and 64.9% of isolated sunspots in average occurred in the northern hemisphere and in the southern hemisphere, respectively, and from 2008 to 2011 in solar cycle 24, 61.3% and 38.7% of sunspot groups and 65.0% and 35.0% of isolated sunspots were observed, respectively. This result shows that the occurrence frequency for each type of sunspot group changes along the solar cycle development, which can be interpreted as the emerging and decaying process of sunspot groups is different depending on the phase of solar cycle. Therefore, it is considered that a following study would contribute to the efforts to understand the dependence of the dynamo mechanism on the phase of solar cycle.
        8133.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Monitoring sunspots consistently is the most basic step required to study various aspects of solar activity. To achieve this goal, the observers must regularly calculate their own correction factor k and keep it stable. Relatively recently, two observing teams in South Korea have presented interesting papers which claim that revisions that take the yearly-basis k into account lead to a better agreement with the international relative sunspot number Ri, and that yearly k apparently varies with the solar cycle. In this paper, using artificial data sets we have modeled the sunspot numbers as a superposition of random noise and a slowly varying background function, and attempted to investigate whether the variation in the correction factor is coupled with the solar cycle. Regardless of the statistical distributions of the random noise, we have found the correction factor increases as sunspot numbers increase, as claimed in the reports mentioned above. The degree of dependence of correction factor k on the sunspot number is subject to the signal-to-noise ratio. Therefore, we conclude that apparent dependence of the value of the correction factor k on the phase of the solar cycle is not due to a physical property, but a statistical property of the data.
        8134.
        2012.05 KCI 등재 서비스 종료(열람 제한)
        This study deals with the design of a spring backboned soft arm, which will be employed for generation of human gesture as an effective means of Human‐Robot interaction. The special features of the proposed mechanism are the light weight and the flexibility of the whole mechanism by using a spring backbone. Thus, even in the case of collision with human, this device is able to absorb the impact structurally. The kinematics and the design for the soft arm are introduced. The performance of this mechanism was shown through experiment emulating several human gestures expressing human emotion and some service contents. Finally, this soft arm was implemented as the wing mechanism of a penguin robot.
        8135.
        2012.04 KCI 등재 서비스 종료(열람 제한)
        Effects of nitrogen (N), phosphorous (P) and potassium (K) on the shoot and bulb growth of wild garlic (Allium victorialis var. platyphyllum) were studied by adopting in vitro culture. These macronutrients influenced the growth of both the shoot and bulb of garlic depending upon their application doses. A minimum of 3% potassium nitrate (KNO3) as a source of nitrogen was found to be critical for shoot elongation while higher concentrations were inhibitory. Garlic bulb growth was profuse on the usual KNO3 strength and sucrose (7%), followed by KNO3 (9.4 mM) supplement. On providing 41.22 mM ammonium nitrate (NH4NO3) as nitrogen source highest shoot growth was observed while 82.45 mM NH4NO3 as a source of nitrogen supported high bulb growth. With regard to potassium a good shoot growth was observed in medium that contained 0.31 mM KH2PO4 and 3% sucrose, while bulb growth was high on 2.5 mM KH2PO4 and 7% sucrose. These experiments may thus direct the development of excellent growth conditions for the commercial production of edible wild garlic.
        8136.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        In order to improve the existing S-57 standard, International Hydrographic Organization(IHO) has developed S-100 standard, a Universal Hydrographic Data Model(UHDM) expanded from ISO 19100 series standard to hydrographic area, and is in the process of its implementation. International Maritime Organization(IMO) has established CMDS based on e-Navigation strategy data standard as International Association of Lighthouse Authorities(IALA) established IHDM based on aids to navigation data standard and each data standard is linked with the S-100 standard. Fundamental concept and core principles of S-100 standard is suitable not only for the development of a wide range of hydrographic data and service production standard, including the next generation ENC, but also the development of product specification of non-hydrographic area. This study has examined the operation principle of S-100 standard and analyzed its implementation process as e-Navigation data in relation with ENC. It also noted the utilization of S-100 standard based e-Navigation and its potential effect via examining the development cases of S-100 standard-based product specification, such as nautical publication, ship reporting and pilot request, digital routing guide, tide and water level transmission and other important data cases of e-Navigation field.
        8137.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        Overtopping Wave Energy Convertor (OWEC) is an offshore wave energy convertor, which comprises the circular ramp and reservoir. It collects the overtopped waves and converting water pressure head into electric power through the hydro-turbines installed in the vertical duct, which is fixed in the sea bed. The performance of OWEC can be represented by the operating water heads of the device, which depends on the amount of the wave water overtopping into the reservoir. In the present paper, the reservoir with the duct connecting to the sea water are studied in the 3D numerical wave tank, which has been developed based on the computational fluid dynamics software Fluent 6.3. Both the overtopping motion and the discharges of the reservoir are investigated together, and several shape parameters and incident wave conditions are varied to demonstrate their effects on the performance of OWEC.
        8138.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        In order to get information on tocopherol content and composition in fifty-six soybean germplasms were evaluated by HPLC. From the principle component analysis, the first three components accounted for 71.6% of the total variance of tocopherol content in the germplasms. Principal component 1 showed significant correlations with all the morphological markers except 100-seed weight. Soybean germplasms were divided into three groups by the first two principal components. The highest content of α -tocopherol was 38.6~mug per g in Tanner, while that of ~gamma -tocopherol was 195.6~mug in PI 91073. In case of δ -tocopherol, IT 105622 showed the highest value as 29.8~mug . The contents of tocopherol were gradually increased from the late August to late September, which was 10 days before maturity, in Alchankong and PI 96322. The tocopherol content was higher in seeds from the plants sown early than those sown late. Total tocopherol contents of PI 96188, Geomjeongkong 2, and Suwon 183 grown in Gimje were higher than those grown in Iksan, but the difference was not observed in PI 96322. These results suggest that the contents of tocopherol in soybean were affected not only by the genotypes but also by environment.
        8139.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        The objective of this study is to develop the gene based sequence tagged site (STS) markers in wheat. The euchromatin enriched genomic library was constructed and the STS primer sets were designed using gene based DNA sequence. The euchromatin enriched genomic (EEG) DNA library in wheat was constructed using the Mcr A and Mcr BC system in DH5α cell. The 2,166 EEG colonies have been constructed by methylated DNA exclusion. Among the colonies, 606 colonies with the size between 400 and 1200 bp of PCR products were selected for sequencing. In order to develop the gene based STS primers, blast analysis comparing between wheat genetic information and rice genome sequence was employed. The 227 STS primers mainly matched on Triticum aestivum (hexaploid), Triticum turgidum (tetraploid), Aegilops (diploid), and other plants. The polymorphisms were detected in PCR products after digestion with restriction enzymes. The eight STS markers that showed 32 polymorphisms in twelve wheat genotypes were developed using 227 STS primers. The STS primers analysis will be useful for generation of informative molecular markers in wheat. Development of gene based STS marker is to identify the genetic function through cloning of target gene and find the new allele of target trait.
        8140.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to develop a functional feed additive for pig with spent Lycium chinense Mill fruit. We investigated the optimum conditions for the extraction of polyphenol from spent Lycium chinense Mill using methanol. Methanol concentration as a solvent for extraction, extraction time and the volume of solvent per a gram of solid (ground spent Lyceum chinense Mill) were selected as parameters. Three levels of parameters were configured according to Box Behnken experiment design, a fractional factorial design, and total 15 trials were employed. Total polyphenol concentration from each trial was used as response from experiment system and effects of parameters on total polyphenol extraction efficiency were determined using response surface model. As a result, all terms in analysis of variance, regression (p = 0.001), linear (p = 0.002), square (p = 0.017) and interaction (p = 0.047) was significant and adjusted determination coefficient (R2) was 94.7%. Total polyphenol extraction efficiency was elevated along increased methanol content and decreased solvent to solid ratio. However extraction time did not affect the efficiency. This study provides a primary information for the optimum extraction conditions to maximize total polyphenol recovery from spent Lycium chinens Mill fruit and this result could be applied to re-use of argo-industrial by-products and to develop of functional feed additives in organic farming.