• Title/Summary/Keyword: Relative elevation

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Schentific analysis and interpretation of visual structure of feng-shui : Case study of Hahoi and Yangdong villages (풍수지리의 시각적 구조의 과학적 분석파 해석 -하회, 양동 마을의 사례 연구-)

  • 현중영;박찬용
    • Journal of the Korean Institute of Landscape Architecture
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    • v.25 no.1
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    • pp.124-134
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    • 1997
  • The primary purpose of this research is to scientifically investigate visual structure of Korean feng-shui at the level of village settlement. This study deals with Hahoi and Yangdong villages of which feng-shui is regarded highly fit to traditional feng-shui principles. Methodologically this research utilizes analytical tools of geographical information systems and statistical analysis methods, Visual structures of the villages'feng-shui are analyzed in terms of elevation, orientation, gradient of slope and relative dominance of visibility of major hills. A mathematical model is suggested to quantify facets of the villages'lung-shui with reference to slope trends. The quantitative analysis results indicate that both villages have good feng-shui. Hahoi village has an excellent feng-shui attributable to a near perfect harmony between water and terrain while Yangdong village has an effective feng-shui facet for conserving energy in terms of microclimate. Principles of fang-shui have potentials to be developed as a holistic planning and design language. Further in-depth research on feng-shui needed to accomplish this goal.

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Fading channel modeling for non-geostationary orbit mobile satellite communication systems (비정지궤도 이동위성통신시스템에서의 페이딩 채널 모델링)

  • You, Moon-Hee;Park, Se-Kyoung;Lee, Soo-In
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.11
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    • pp.12-18
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    • 1998
  • In non-geostationary orbit(NGSO) satellite communication links, satellite's elevation angle at terminal is changed continuously because of the satellite movement relative to earth surface. Therefore the characteristics of the fade-effected signal received by a terminal from a NGSO satellite is also varied continuously even if the terminal is operated at fixed location. In this paper, we determine a general statistic model for the fading characteristics over NGSO satellite communication links and set up the parameters of the fading model in terms of the elevation angle according to various propagation environment and find the parameter values using the data of fading margin for commercial NGSO mobile satellite communication systems. And the fading charateristics for each environment are analyzed using this model. These results can be applied to develop the compensation algorithm and to analyze the performance of the transmission schemes for NGSO mobile satellite communication systems.

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Assessment of Tissue Perfusion Following Conventional Liposuction of Perforator-Based Abdominal Flaps

  • Dogan, Zeynep Deniz Akdeniz;Sacak, Bulent;Yalcin, Dogus;Pilanci, Ozgur;Tuncer, Fatma Betul;Celebiler, Ozhan
    • Archives of Plastic Surgery
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    • v.44 no.2
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    • pp.109-116
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    • 2017
  • Background The effect of liposuction on the perforators of the lower abdominal wall has been investigated in several studies. There are controversial results in the literature that have primarily demonstrated the number and patency of the perforators. The aim of this study was to determine the effect of liposuction on the perfusion of perforator-based abdominal flaps using a combined laser-Doppler spectrophotometer (O2C, Oxygen to See, LEA Medizintechnik). Methods Nine female patients undergoing classical abdominoplasty were included in the study. Perforators and the perfusion zones of the deep inferior epigastric artery flap were marked on the patient's abdominal wall. Flap perfusion was quantitatively assessed by measuring blood flow, velocity, capillary oxygen saturation, and relative amount of hemoglobin for each zone preoperatively, after tumescent solution infiltration, following elevation of the flap on a single perforator, and after deep and superficial liposuction, respectively. Results The measurements taken after elevation of the flap were not significantly different than measurements taken after the liposuction procedures. Conclusions The liposuction procedure does not significantly alter the perfusion of perforator-based abdominal flaps in the early period. The abdominal tissue discarded in a classic abdominoplasty operation can be raised as a perforator flap and has been demonstrated to be a unique model for clinical research.

Phenidone, a dual inhibitor of cyclooxygenase and lipoxygenase, inhibits carbon tetrachloride-induced acute liver injury in rats

  • Choi, Hyuop;Joeng, Donghwan;Jung, Bae-Dong;Shin, Taekyun;Wie, Myung-Bok
    • Korean Journal of Veterinary Research
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    • v.50 no.2
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    • pp.145-149
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    • 2010
  • This study was carried out to find whether phenidone (1-phenyl-3-pyrazolidinone), a cyclooxygenase as well as a lipoxygenase inhibitor, exhibits the preventive effect on carbon tetrachloride $(CCl_{4})-induced$ acute liver injury in rats. Rats were pretreated with phenidone at a dose of 50 or 200 mg/kg (p.o.) once daily for 3 consecutive days before $CCl_{4}$ administration. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Malondialdehyde (MDA) production was determined as an index of lipid peroxidation in the liver and serum. The histopathological changes in the liver were also examined in each group. The reduction in body weights was significantly inhibited in the phenidone-treated group than in the $CCl_{4}$ control group. Significant increase in the relative liver weights of the phenidone-treated groups was observed compared with either the vehicle or $CCl_{4}$ groups. Elevation of serum AST and ALT activities occurred after $CCl_{4}$ treatment was significantly attenuated by the pretreatment with phenidone. The elevation of MDA levels in liver and serum were completely inhibited in phenidone-treated groups. The protective effects on phenidone-treated groups were confirmed histopathologically. These results suggest that phenidone may be a useful protector through modulation of hepatic inflammation in $(CCl_{4})-induced$ acute liver injury.

Principal Component Analysis Based Ecosystem Differences between South and North Korea Using Multivariate Spatial Environmental Variables (다변량 환경 공간변수 주성분 분석을 통한 남·북 생태계 차이)

  • Yu, Jaeshim;Kim, Kyoungmin
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.4
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    • pp.15-27
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    • 2015
  • The objectives of this study are to analyze the quantitative ecological principal components of Korean Peninsula using the multivariate spatial environmental datasets and to compare the ecological difference between South and North Korea. Ecological maps with GIS(Geographical Information System) are constructed by PCA(Principal Component Analysis) based on seventeen raster(cell based) variables at 1km resolution. Ecological differences between South and North Korea are extracted by Factor Analysis using ecosystem maps masked from Korean ones. Spatial data include SRTM(Shuttle Radar Topography Mission), Temperature, Precipitation, SWC(Soil Water Content), fPAR(Fraction of Photosynthetically Active Radiation) representing for a productivity, and SR(Solar Radiation), which all cover Korean peninsula. When it performed PCA, the first three scores were assigned to red, green, and blue color. This color triplet indicates the relative mixture of the seventeen environmental conditions inside each ecological region. The first red one represents for 'physiographic conditions' worked by high elevation and solar radiation and low temperature. The second green one stands for 'seasonality' caused by seasonal variations of temperature, precipitation, and productivity. The third blue one means 'wetness condition' worked by high value such as precipitation and soil water contents. FA extraction shows that South Korea has relatively warm and humid ecosystem affected by high temperature, precipitation, and soil water contents whereas North Korea has relatively cold and dry ecosystem due to the high elevation, low temperature and precipitation. Results would be useful at environmental planning on inaccessible land of North Korea.

Molecular Characterization of Dissolved Organic Matter Unveils their Complexity, Origin, and Fate in Glacier and Glacial-Fed Streams and Lakes on the Tibetan Plateau

  • Kim, Min Sung;Zhou, Lei;Choi, Mira;Zhang, Yunlin;Zhou, Yongqiang;Jang, Kyoung-Soon
    • Mass Spectrometry Letters
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    • v.12 no.4
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    • pp.192-199
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    • 2021
  • Alpine glaciers harbor a large quantity of bio-labile dissolved organic matter (DOM), which plays a pivotal role in global carbon cycling as glacial-fed streams are headwaters of numerous large rivers. To understand the complexity, origin, and fate of DOM in glaciers and downstream-linked streams and lakes, we elucidated the molecular composition of DOM in two different Tibetan Plateau glaciers, eight glacial-fed streams and five lakes, using an ultrahigh-resolution 15 Tesla Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. The compositional changes of the DOM samples revealed that glacier DOM mostly exhibited sulfur-containing organic compounds (CHOS species). We also found that aliphatic formulae contributed more than 50% of the total abundance of assigned molecules in glacier samples, and those compounds were significantly related to CHOS species. The CHO proportions of glacial-fed streams and lakes samples increased with increasing distance from glacial terminals. The relative contribution of terrestrial-derived organics (i.e., lignins and tannins) declined while microbial-originated organics (aliphatics) increased with increasing elevation. This suggested the gradual input of allochthonous materials from non-glacial environment and the degradation of microbe-derived compounds along lower elevations. Alpine glaciers are retreating as a result of climate change and they nourished numerous streams, rivers, and downstream-linked lakes. Therefore, the interpretations of the detailed molecular changes in glacier ice, glacial-fed streams, and alpine lakes on the Tibetan Plateau could provide broad insights for understanding the biogeochemical cycling of glacial DOM and assessing how the nature of DOM impacts fluvial ecosystems.

Evaluation of Non-infarct-Related Arteries Using C-11 Acetate PET in STEMI With Multivessel Disease

  • Sang-Geon Cho;Minchul Kim;Seung Hun Lee;Ki Seong Park;Jahae Kim;Jang Bae Moon;Ho-Chun Song
    • Journal of Cardiovascular Imaging
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    • v.30 no.3
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    • pp.169-180
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    • 2022
  • BACKGROUND: We analyzed whether C-11 acetate positron emission tomography (PET) can be used for the evaluation of non-infarct-related artery (NIRA) in patients with ST-elevation myocardial infarction (STEMI) and multivessel disease. METHODS: We prospectively enrolled 31 patients with STEMI and at least one NIRA stenosis (diameter stenosis [DS] ≥ 50%). C-11 acetate PET was performed after successful revascularization for the infarct-related artery (IRA). Myocardial blood flow (MBF) and oxidative metabolism (kmono) were measured and compared between NIRA vs. IRA, stenotic (DS ≥ 50%) vs. non-stenotic (DS < 50%) NIRAs, and NIRAs with significant stenosis (DS ≥ 70% or fractional flow reserve [FFR] ≤ 0.80) vs. those without (neither DS ≥ 70% nor FFR ≤ 0.80). The correlations between PET and angiographic parameters were also analyzed. RESULTS: MBF and kmono were significantly higher in NIRAs than those in IRAs. Stenotic NIRAs showed significantly reduced stress MBF, myocardial flow reserve (MFR), relative flow reserve (RFR) (0.72 ± 0.12 vs. 0.82 ± 0.14; p = 0.001), and stress kmono, as compared to those in non-stenotic NIRAs. NIRAs with significant stenosis had significantly lower stress MBF, MFR, and RFR (0.70 ± 0.10 vs. 0.80 ± 0.14; p = 0.001). RFR showed the best, but modest linear correlation with DS of NIRA stenosis (r = -0.429, p = 0.001). RFR > 0.81 could effectively exclude the presence of significant NIRA stenosis. CONCLUSIONS: C-11 acetate PET could be a feasible alternative noninvasive modality in patients with STEMI and multivessel disease, by excluding the presence of significant NIRA stenosis.

Relative importance of climatic and habitat factors on plant richness along elevation gradients on the Mt. Baekhwa, South Korea (백화산 고도별 식물 종풍부도에 대한 기후 및 서식지 인자의 상대적 중요성)

  • Lee, Chang-Bae;Chun, Jung-Hwa
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.3
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    • pp.233-242
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    • 2018
  • This study explored the richness patterns of vascular plant species and evaluated the effects of the climatic and habitat variables on the observed patterns along elevational gradients on the Mt. Baekhwa, South Korea. Plant data were recorded from 70 plots and a total of 187 plant species with 78 woody and 109 herbaceous species were recorded along two study transects, the Banyasa and Bohyunsa transects, on the Mt. Baekhwa. A total of 154 plant species with 66 woody and 88 herbaceous species and 131 plant species with 58 woody and 73 herbaceous species were recorded along the Banyasa and Bohyunsa transects, respectively. We used simple ordinary least squares regression model, multi-model inference and variation partitioning to analyze the relative contribution of climatic and habitat variables on the elevational richness patterns. Species richness pattern for vascular plants along the Banyasa transect monotonically decreased with elevation, whereas plant species richness showed reversed hump-shaped pattern along the Bohyunsa transect. Although the elevational patterns of species richness for vascular plants were different between the both transects, habitat variables are more important predictors than climatic variables for the elevational patterns of plant species richness along our study transects on the Mt. Baekhwa. These results indicate that elevational diversity patterns of vascular plants may be different even between nearby elevational transects in a mountain ecosystem but the diversity patterns may be controlled by same drivers.

Effects of Micro-topography on Vegetation Pattern in Dunchon-dong Wetland (둔촌동 습지에서 미지형이 식물 군락 구성에 미치는 영향)

  • Nam, Jong Min;Jeon, Seung-Hye;Choi, Ho;Kim, Jae Geun
    • Journal of Wetlands Research
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    • v.16 no.4
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    • pp.353-362
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    • 2014
  • The purpose of this study is to investigate the effect of micro-topography to vegetation pattern in Dunchon-dong wetland. To characterize the effect of micro-topography, changes in water level and vegetation pattern were monitored from 2007 to 2008. Depending on the relative elevation, the study site was divided into 4 sectors. The relative areas of sectors in ascending order were 11%, 10%, 18% and 24%, respectively. During investigation period, average water pH was 6.10 (${\pm}0.13$), electron conductivity was $51.5({\pm}6.0){\mu}s/cm$, $PO_4$-P, $NO_3$-N and $NH_4$-N concentration were $0.04({\pm}0.02)mg/L$, $0.14({\pm}0.07)mg/L$, and lower than 0.01mg/L, respectively. Water level was very changeable in low-water season because the area of lowest sector was small. This characteristic increased the effect of difference of accumulated precipitation from March to April in 2007 and 2008 to plant community composition in lower sectors. Different plant guilds dominated respective sectors and annual plants were major dominant species in the study site. This study suggested that the elevation gradients are necessary to create the habitats for various plant guilds in wetland.

Hepatoprotective effect of fermented Schizandrae Fructus Pomace extract and Hoveniae Semen Cum Fructus extract combination mixtures against carbon tetrachloride-induced acute liver injured mice (사염화탄소 유발 급성 간 손상에 대한 발효 오미자박 및 헛개과병 추출물의 혼합 비율에 따른 간 보호효능)

  • Hye-Rim, Park;Kyung Hwan, Jegal;Beom-Rak, Choi;Jae Kwang, Kim;Sae Kwang, Ku
    • Herbal Formula Science
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    • v.31 no.1
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    • pp.53-65
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    • 2023
  • Objectives : Present study investigated the hepatoprotective effects and the optimal mixing ratio of fermented Schizandrae Fructus Pomace (fSFP) and Hoveniae Semen Cum Fructus (HSCF) extract combination in carbon tetrachloride (CCl4)-induced acute liver injury mice. Methods : ICR mice were orally administered with 200 mg/kg of fSFP, HSCF and mixtures of fSFP and HSCF [MSH (w:w); 1:1, 1:2, 1:4, 1:6, 2:1, 4:1, 6:1, and 8:1] for 7 consecutive days. Silymarin (100 mg/kg) was administered as a reference drug. 0.5 mL/kg of CCl4 was injected intraperitoneally to induce acute liver injury. Body weight gain, relative liver weight, serum chemistry, histopathological analysis, and hepatic endogenous antioxidants capacities were observed. Results : All diverse combinations of MSH significantly reduced relative liver weight increase by CCl4. In addition, MSH administrations significantly decreased the elevation of serum alanine aminotransferase and aspartate aminotransferase activities by CCl4. Histopathological observation indicated that all MSH treatments significantly reduced the increase of degenerated hepatocytes, inflammatory cell infiltration, and histological activity index score by CCl4. Moreover, all MSH administrations reduced the elevation of malondialdehyde contents, and ameliorated the reduction of hepatic glutathione contents, superoxide dismutase activity, and catalase activity. Among the various mixing ratio of MSH combinations, MSH 1:1 and 2:1 showed the most potent anti-oxidative stress, and hepatoprotective effect. Conclusion : Present results suggest that 1:1 and 2:1 combinations of MSH is promising herbal formulation with the hepatoprotective effect against oxidative stress.