• Title/Summary/Keyword: central series

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Dynamic Response of Plate Structure Subject to the Characteristics of Explosion Load Profiles - Part A: Analysis for the Explosion Load Characteristics and the Effect of Explosion Loading Rate on Structural Response - (폭발하중 이력 특성에 따른 판 구조물의 동적응답 평가 - Part A: 폭발하중 특징 및 재하속도의 영향 분석 -)

  • Kang, Ki-Yeob;Choi, Kwang-Ho;Ryu, YongHee;Choi, JaeWoong;Lee, Jae-Myung
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.28 no.2
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    • pp.187-195
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    • 2015
  • The gas explosions in offshore installations are known to be very severe according to its geometry and environmental conditions such as leak locations and wind directions, and a dynamic response of structures due to blast loads depends on the load profile. Therefore, a parametric study has to be conducted to investigate the effects of the dynamic response of structural members subjected to various types of load shapes. To do so, a series of CFD analyses was performed using a full-scale FPSO topside model including detail parts of pipes and equipments, and the time history data of the blast loads at monitor points and panels were obtained by the analyses. In this paper, we focus on a structural dynamic response subjected to blast loads changing the magnitude of positive/negative phase pressure and time duration. From the results of linear/nonlinear transient analyses using single degree of freedom(SDOF) and multi-degree-of freedom(MDOF) systems, it was observed that dynamic responses of structures were significantly influenced by the magnitude of positive and negative phase pressures and negative time duration.

The Effects of Ginseng Saponin on Animal Behavior (인삼(人蔘)사포닌의 동물행동(動物行動)에 대(對)한 작용(作用))

  • Hong, S.A.;Park, C.W.;Kim, J.H.;Hong, S.K.;Chang, H.K.;Kim, M.S.
    • The Korean Journal of Pharmacology
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    • v.10 no.2
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    • pp.1-11
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    • 1974
  • Results of an experiment on the behavior of rats and mice in order to explore the possible pharmacological actions of Panax ginseng upon the central nervous system can be summarized as follows: 1. Spontaneous motor activity. In the case of mice, those groups who were administered 2.5 mg and 5.0mg of ginseng saponin per kilogram of body weight were observed to have increased their activity compared with the control group, while the 50.0 mg and 100.0 mg per kilogram body weight groups demonstrated lower levels of activity, with the peak of activity appearing at 30 minutes after administration of drugs. In the case of rats, those groups of animals who were given injections in the dosage of 2.5 mg, 5.0 mg and 50.0 mg per kilogram body weight demonstrated higher activity than the control group, while the 100.0 mg per kilogram group appeared to have decreased in their activity, with the peak action appearing 30 minutes after the administration of ginseng saponin. The 50.0 mg per kilogram group demonstrated no significant differential. 2. General behavior analysis. In the case of mice, decrease in sleeping component of behavior and increase in the walking and roaring components, compared those with the control group, turned out to be a common phenomenon among the groups who were administered 2.5 mg, 5.0 mg and 50.0 mg of ginseng saponin per kilogram body weight, with the 5.0 mg per kilogram group standing out of all the other groups in terms of their reactions. In the case of rats, ginseng saponin appeared to reduce sleeping component with 2.5 mg, 5.0 mg and 50.0 mg per kilogram body weight groups, while increased the walking and rearing components. It was observed that administratoin of ginseng saponin in a dose of 2.5 mg per kilogram appeared to markedly increase the lying and grooming components of animal behavior. 3. Open-field exploratory behavior. Adminstration of ginseng saponin to mice in doses of 5.0 mg, 50.0 mg and 100.0 mg per kilogram body weight decreased activity, but increased their exploratory behavior. In the case of rats, however, administration of ginseng saponin in the doses of 2.5 mg and 5.0 mg per kilogram body weight markedly increased their activities, while decreased activities with the 50.0 mg per kilogram and 100.0 mg per kilogram groups. The exploratory behavior of rats appeared to have decreased, while grooming increased ramarkably. 4. The above findings from a series of experiment appear to suggest a stimulating effect on the central nervous system when ginseng saponin is administered in small doses, but that larger doses might result in an inhibitory effect, though differential results can be anticipated with modification of experimental conditions.

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Temperature Changes of Climatic Solar Terms and Their Spatiotemporal Characteristics in South Korea (우리나라 기후 절기별 기온 변화의 시공간적 특성 분석)

  • Jin, Mi Jeong;Park, Sunyurp
    • Journal of the Korean Geographical Society
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    • v.50 no.1
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    • pp.23-36
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    • 2015
  • The temperature change patterns of climatic solar terms and their climatic fitness were analyzed. Harmonic analysis based on thirty-year(1981-2010) time-series data from sixty one weather stations across South Korea showed that the central peaks of the extreme heat had shifted toward start of autumn with increasing mean temperature. The overall climatic fitness of solar terms, such as major heat, frost descent, major snow, and major cold, was low, and it showed significant regional variations. The actual meteorological phenomenon representing each climatic solar term was observed much later than the day of the solar term at most weather stations. The number of observations, where an actual meteorological condition for each climatic solar term was recorded within ${\pm}1$ week from the day of that solar term, ranged only from 7.7% to 40.4% of the entire data. Study results also showed that the climatic fitness of major heat, frost descent, and major snow gradually changed in the east-west direction. Major cold, a solar term with higher climatic fitness, was influenced more strongly by latitude than longitude. Considering geographically uneven magnitude and trends in temperature changes, rearrangement and adjustment of time intervals between the solar terms may help us improve their applicability as realistic indicators of seasonal changes.

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THE CIRCULATION IN CHINJU BAY 2. Results of Drift Bottle Experiments (진주만의 해수 유동에 관하여 2. 해류병 표류 실험 결과)

  • CHANG Sun-duck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.2
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    • pp.137-147
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    • 1970
  • From November 1968 to March 1970, a series of drift bottle experiments were carried out in waters adjacent to and in Chinju Bay with the following results. Of the bottles released, $50\~69$ per cent were recovered. 1. The circulation of Chinju Bay is usually caused by the tidal current except during the winter season when the northwest monsoon prevails to cause a wind-drift current. 2. Sea water in the southern part of Chinju Bay flows northward at ebb tide. The ebb current east of the central submarine bank in Chinju Bay flows northeastward toward Samchonpo Channel through the eastern depression of the bank contributing to form a cyclonic eddy. The ebb current west of the bank, however, flows northward toward Noryang Channel through the western depression of the bank. 3. The ebb current nea. the southernmost part of Chinju Bay flows eastward toward Chijok Channel. 4. At flood tide, the main stream of the tidal current in Noryang Channel flows eastward. Turning smoothly to the right, the southern branch of the flood current flows southward through the depression and along the isobaths at the western margin of the central submarine bank, while the northern branch, turning to the left, flows into the Chin-gyo Bay of Hadong. 5. flood current in the eastern area of Kwang-yang Inlet runs northeastward toward Noryang Channel. A small eddy develops near Kwanumpo of Namhae Island. 6. The results suggest that such a drift bottle experiment can be recommended for the attestation of currents, although it is not suitable for a quantitative study of coastal currents.

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Analysis of GPS signal environment at DGNSS stations (DGNSS 기준국 관측환경 분석)

  • Sohn, Dong-Hyo;Park, Kwan-Dong;Won, Ji-Hye;Choi, Yong-Kwon;Kee, Chang-Don
    • Journal of Navigation and Port Research
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    • v.35 no.8
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    • pp.625-629
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    • 2011
  • In this study, we analyzed the signal environment of 17 DGNSS stations operated by DGPS Central Office through TEQC quality checking, visibility analysis and site visits. With TEQC, we produced times series of four indices of TEQC quality checking: observation ratio, L1 pseudorange multipath, L2 pseudorange multipath, and the frequency of cycle slip events. From visibility analysis, the directions where missing observations are happening were identified and the result was verified through onsite investigation. Without considering TEQC indices at the six sites(Palmido, Eochungdo, Geomundo, Pyeongchang, Seongju, and Chungju), the average TEQC indices were: 98% observation ratio, 0.19m of L1 pseudorange multipath, 0.71m of L2 pseudorange multipath, and 1.3 cycle slips per 1000 observations. The observation ratios at Palmido and Eochungdo were low. It was found that receiver settings were incorrect so that they could track the P2 signal of GPS satellites with L2C capability. No signal-blocking obstacles were found around the Geomundo station except the lighthouse. Thus, we guess that the poor TEQC indices at the site are believed to be caused by problems in the GPS hardware or cables. The low observation ratio at Pyeongchang is being caused by the surrounding hills blocking the satellite view from the south to the northwest directions. Even though all of four TEQC indices were bad at Seongju and Chungju stations, we found that the signal reception environment at the two sites is in good condition. We think that the quality indices got poor probably because of malfunctioning equipment. So, further investigation is needed for the Seongju and Chungju sites.

Type and Evolution of the Myeonbongsan Caldera in Southern Cheongsong, Korea (청송남부 면봉산 칼데라의 유형과 진화)

  • 황상구;김성규
    • The Journal of the Petrological Society of Korea
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    • v.8 no.3
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    • pp.171-182
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    • 1999
  • The Myeonbongsan caldera, 10.2X8.0 km, developed within older sequences of sedimentary formations and intermediate composition volcanis in the southern Cheongsong area. Volcanic rocks in the caldera block include lower intermediate volcanics, middle tuffaceous sequences and upper silicic ones. The silicic volcanics, which is named Myeonbongsan Tuff, are composed of crystal-rich ash-flow tuff(300 m) , bedded tuff(30 m) and pumice-rich ash-flow tuff(700 m) in ascending order. Several intrusions dominate the early sequences within the caldera. The caldera collapsed in a trapdoor type when silicic ash-flow tuffs erupted fro major vent area in the caldera. Normal faulting along a ring fault system except the southwestern part dropped the tuffs down to the northrase with a maximum displacement of about 820 m. The Myeonbongsan Tuff is just about 1,030 m thick inside the northeastern caldera, with its base not exposed, and southwestward thinning down. Rhyolitic plug and ring dikes are emplaced along the central vent and the caldera margins, and the ring dikes are cut by plutonic stocks in the southeastern and northwestern parts. The caldera volcanism eviscerated the magma chamber by a series of explosive eruptions during which silicic magma was erupted to form the Myeonbongsan Tuff. Following the last ash-flow eruption, collapse of the chamber roof resulted in the formation of the Myeonbongsan caldera, a subcircular trapdoor-type depression subsiding about 820 m deep. After the collapse, stony to flow-banded rhyolites were emplaced as circular plugs and ring dikes along the central vent and the caldera margins respectively. Finally after the intrusions, another plutons were emplaced as stocks outside the caldera.

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Monosaccharide as a Central Scaffold Toward the Construction of Salicylate-Based Bidentate PTP1B Inhibitors via Click Chemistry

  • Tang, Yan-Hui;Hu, Min;He, Xiao-Peng;Fahnbulleh, Sando;Li, Cui;Gao, Li-Xin;Sheng, Li;Tang, Yun;Li, Jia;Chen, Guo-Rong
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.1000-1006
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    • 2011
  • The discovery of carbohydrate-based bioactive compounds has recently received considerable interest in the drug development. This paper stresses on the application of 1-methoxy-O-glucoside as the central scaffold, whereas salicylic pharmacophores were introduced with diverse spatial orientations probing into the structural preference of an enzymatic target, i.e. protein tyrosine phosphatase 1B (PTP1B). By employing regioselective protection and deprotection strategy, 2,6-, 3,4-, 4,6- and 2,3-di-O-propynyl 1-methoxy-O-glucosides were previously synthesized and then coupled with azido salicylate via click chemistry in forming the desired bidentate salicylic glucosides with high yields. The inhibitory assay of the obtained triazolyl derivatives leads to the identification of the 2,3-disubstituted salicylic 1-methoxy-O-glucoside as the structurally privileged PTP1B inhibitor among this bidentate compound series with micromole-ranged $IC_{50}$ value and reasonable selectivity over other homologous PTPs tested. In addition, docking simulation was conducted to propose a plausible binding mode of this authorized inhibitor with PTP1B. This research might furnish new insight toward the construction of structurally different bioactive compounds based on the monosaccharide scaffold.

The Formation and Development of the Archival System in the Primorskii Krai of the Russian Federation (러시아 연해변강주(沿海邊疆州)에서의 기록관리업무의 성립과 발전)

  • Cho, Ho-yeon
    • The Korean Journal of Archival Studies
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    • no.12
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    • pp.237-272
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    • 2005
  • This paper aims to research the historical development of the archival systems in the Primorskii Krai of the Russian Federation. The history of the archives in this region might be divided into the three periods. The first period extended from the territorial acquisition of the Far East to 1938, when the international situation reached the crisis. From then to the end of the Second World War the history of the archives of the Primorskii Krai underwent the second period. The third period has ranged from 1945 to the present day. As the imperialistic countries, including England, Germany and Russia, claimed and conquered the lands in China in the last decade of the nineteenth century, the Russian government was forced to produce a lot of records, which resulted in the establishment of the several archival institutions in the Far East region. Although the Soviet government issued "Decree On the Reorganization and Centralization of Archival Affairs in the Russian Socialist Federated Soviet Republic" in 1918, the political turmoils prevented the Primorskii region from constructing the archival system. However, A. P. Georgievskii and his colleagues made desperate efforts to arrange the archival administration. Thanks to their struggles, the Far Eastern Republic, a buffer state, which existed from April 6, 1920 to November 14, 1922, passed the autonomous regulation, which defined the organization of the committee for the archival administration in the Primorskii region. The Primorskii Krai Archive originated from the committee. As the international situation became aggravated in the East Asia, the Soviet government made a decision to evacuate the records from the Far East region to the western Siberian cities like Tomsk, Omsk and Minusinsk. It was on August 1943 that the Central National Archive of the Far East of RSFSR was established in Tomsk. After the end of the Second World War, the main archival institutions of the Primorskii Krai, that is, the Central National Archive of the Far East of RSFSR and the Primoskii Krai Archive have played an important role in the archival administration in this region. The archivists have not only prepared the catalogues, but also proceeded the descriptions of the archival collections. Furthermore, the archival institutions of the Primorskii Krai have published a series of archives and contributed to the development of the archival system in the Far East of the Russian Federation. It might be concluded that the archives of the Primorskii Krai, reaching were the products of the desperate efforts which the archivists of this region made from the 19th century to the present day, regardless of the political changes.

The Roles of Dietary Polyphenols in Brain Neuromodulation (뇌 신경조절에서의 식이 폴리페놀 화합물의 역할)

  • Lee, Hyeyoung;Lee, Heeseob
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1386-1395
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    • 2018
  • Over recent years, it has become evident that the central nervous system bidirectionally interacts with the gastrointestinal tract along the gut-brain axis. A series of preclinical studies indicate that the gut microbiota can modulate central nervous system function through a multitude of physiological functions. Polyphenols are ubiquitous plant chemicals included in foods such as fruits, vegetables, tea, coffee and wine, and their consumption is directly responsible for beneficial health effects due to antioxidant, anti-inflammatory, antimicrobial, immunomodulatory, anticancer, vasodilating, and prebiotic-like effects. There is increasing evidence that dietary polyphenol can contribute to beneficial effects in neuronal protection acting against oxidative stress and inflammatory injury as well as in cognitive functions. In this paper, we overview the neuroprotective role of dietary polyphenols especially focusing on the neuroinflammation and neurovascular function by interaction with the gut microbiome. Polyphenol metabolites could directly act as neurotransmitters crossing the blood-brain barrier and modulating the cerebrovascular system or indirectly modulating gut microbiota. In addition, evidence suggests that dietary polyphenols are effective in preventing and managing neurological disorders, such as age-related cognitive decline and neurodegeneration, through a multitude of physiological functions. Dietary polyphenols are increasingly envisaged as a potential nutraceuticals in the prevention and treatment of neurological disorders, because they possess the ability to reduce neuroinflammation, to improve memory and cognitive function and to modulate the gut microbiota.

Effects of fermented soybean meal with Bacillus velezensis, Lactobacillus spp. or their combination on broiler performance, gut antioxidant activity and microflora

  • Tsai, C.F.;Lin, L.J.;Wang, C.H.;Tsai, C.S.;Chang, S.C.;Lee, T.T.
    • Animal Bioscience
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    • v.35 no.12
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    • pp.1892-1903
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    • 2022
  • Objective: A series of experiment were conducted to evaluate the effects of replacing a part of soybean meal (SBM) at 6% of broiler diets with fermented soybean meal (FSBM) obtained by single or two-stage fermentation by measuring growth performance, antioxidant activity in the jejunum and distal intestinal microflora. Methods: Soybean meal samples were prepared by single-stage fermentation using Bacillus velezensis (Bv) (FSBMB), or Lactobacillus spp. (as commercial control) (FSBML). Additional SBM sample was prepared by two-stage fermentation using Bv and subsequently using Lactobacillus brevis ATCC 367 (Lb) (FSBMB+L). Enzyme activity, chemical composition, trichloroethanoic acid-nitrogen solubility index (TCA-NSI) and antioxidant activity were measured. Then, in an in vivo study, 320 Ross308 broilers were divided into four groups with ad libitum supply of feed and water. Four groups were fed either a corn-soybean meal diet (SBM), or one of fermented SBM diets (FSBMB+L, FSBMB, and FSBML). Growth, serum characteristics, microflora, and the mRNA expression of selected genes were measured. Results: Compared to SBM, FSBMB+L contained lower galacto-oligosaccharide, allergic protein, and trypsin inhibitor, and higher TCA-NSI by about three times (p<0.05). Reducing power and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging ability correlated positively with the TCA-NSI content in FSBM. Growth performances were not significantly different among four groups. In jejunum of 35-day-old broilers, partial replacement of SBM by FSBMB+L increased the activity of superoxide dismutase and catalase (CAT), and the FSBMB group had the highest catalase activity (p<0.05). Partial replacement of SBM by FSBM increased relative mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and peptide transporter 1 (PepT1) (p<0.05); however, FSBMB+L increased CAT mRNA level to 5 times of the control (p<0.05). Conclusion: Using Bv- and Lb-processed SBM through two-stage fermentation to partially replace 6% of diets will improve the gut's antioxidant activity under commercial breeding in broilers.