• Journal of Environmental Science International
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• v.14 no.9
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• pp.817-825
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• 2005

The purpose of this study was to research about salt marsh flora and vegetation in the Dongjin-river estuary area where has a project for Sea Man Geum Reclaimed Land so that we can foster foundation on restoration of an ecological habitat, development of applicable plant and establishment of a conservation policy after deceloping the reclaimed land for salt marsh vegetation which has great value ecologically. In conclusion, we was distributed that there are 7 families 21 genera, 25 species, 2 varieties of vascular plant at the Dongjin-river estuary area which have 27 taxa in total and are $0.64\%$ among 4,191 of korean vascular plant. There are also 2 family, 2 genus, 2 species of a naturalized plant which are $1.1\%$ of indicator of a naturalized plant salt marsh vegetation of the downstream are very much affected by the time of inundation, tidal water so that a low degree of salt marsh has frequent flooding by sea water and has a pure group of Suaeda japonica. A Phragmites communis, Carex scabrifolia are distributed mainly around a waterway of salt marsh and Zoysia sinica, Atriplex subcordata, Phragmites communis are living in stock as forming into patch around medium salt marsh. Suaeda asparagoides, Phacelurus latifolius are living around a little high ground and a Phragmites communis is a behind vegetation of Phacelurus latifolius and a part of the Phragmites communis are living along with waterway in a salt marsh as a community. By the 2-M method twelve plant communities were recognized ; Suaeda japonica. Carex scabrifolia, Zoysia sinica, Artemisia scoparia, Phacelurus latifolius, Phragmites communis, Suaeda maritima, Suaeda japonica-Atriplex gmelini, Phragmites communis-Suaeda japonica, Suaeda japonica-Salicornia herbacea, Salicornia herbacea-Suaeda aspar-agoides and Scirpus planiculmis community. The actual vegetation map was constructed on the grounds of the communities classified and other data.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.237-246
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• 2003

A mountain village is defined as that which is autogenously formed over at least 100 years and supported by agricultural yields and forest products and forest area portion of which is over 70% in Guidelines for the Comprehensive Development Planning of Mountain Village. Recently, concerns about management planning of the Green and Eco-Village causes researches related to the Mountain Village's economics, tourism attractiveness, experience programming and investigation of the ecosystem and environment based on the village area. This kind of eco-village project should be supported by ecological evaluation of its spatial structure. But there is rare research of the village spatial structure studied from the ecological viewpoint originally. The purpose of this study is to interpret the spatial structure of Korean mountain village on the landscape ecological paradigm. The paradigm components are patches, corridors, networks, and matrix which explain the land and spatial structure at landscape scale. For this purpose, we selected two case study areas- Sansu and Ajick villages in Gimje city, Jeonlabukdo. We interpreted and evaluated the spatial structure by three steps: (1) to clarify the existing land mosaic pattern by land use mapping (2) to estimate the pore size as development area in matrix (3) to investigate the funnel effect of patch shape. These landscape ecological steps and frameworks could be applied for the proper methodology as fundamentals of eco-village planning and design.

• The Korean Journal of Ecology
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• v.27 no.5
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• pp.257-261
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• 2004

Juniperus chinensis var. sargentii Henry is a short and creeping evergreen shrub which reaches about 50㎝ in height and occurs in the northeast Asia and in high mountains over the South Korea. Its distribution is restricted, and the number of individuals are gradually decreasing. This study was conducted to estimate spatial pattern, genetic diversity and spatial genetic structure of J. chinensis var. sargentii. A total of 131 clumps were studied in the study area (40m × 60m). The spatial pattern of this population was random (Aggregation index R=1.031). In spite of the small number and the limited distribution, the level of genetic diversity (Shannon's index 1=0.463) was relatively high as compared with those of other plant species with similar ecological characteristics. ISSR genotypes of all individuals were investigated to find the genetic relationship of clumps and genets. Fifteen clumps were composed to be clones, and a total of 116 unique genotypes were composed by separate genets. Spatial autocorrelation analysis using Tanimoto distance showed that the genetic patch was established within 8m. The effect of clonal reproduction on genetic structure was almost nothing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.7 s.110
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• pp.648-658
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• 2006

We propose a thin frequency selective surface(FSS) superstrate etched on a substrate for dual-band directivity enhancement, and present a design method of the superstrate. In the proposed new design, two FSS arrays with the same periodicity, but with different alignments are placed above and below a thin dielectric layer to overcome the problem of conventional superstrates for dual band directivity enhancements. Based on the unit-cell simulation, several important parameters that characterize the thin FSS superstrate are investigated, and the procedure for designing such a superstrate is described. We compare the resonant frequencies and the qualify factors of the unit cell with those of three FSS antenna composites with different quality factors, and identify the quality factors which support similar directivity enhancement at the dual-band directivity enhancement. It was found that there is an optimum FSS array size of a superstrate to enhance the directivity most efficiently. Measured results for a fabricated superstrate show a good agreement with the simulated ones.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.8
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• pp.615-623
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• 2018

The probability density function(PDF) for the amplitude of the reflectivity of low-grazing-angle sea clutter has generally been modeled by a compound-Gaussian distribution, rather than by the Rayleigh distribution, owing to the intensity variation of each clutter patch over time. The texture component forming the reflectivity has been simulated by combining Gamma distribution and memory-less nonlinear transformation(MNLT). On the other hand, there is no typical method available that can be used to simulate the speckle component. We first review Watt's method, wherein the speckle is simulated starting from the Doppler spectrum of the received echoes that is modeled as having a Gaussian shape. Then, we introduce a newly proposed method. The proposed method simulates the speckle by manipulating a clutter covariance matrix through the Cholesky decomposition after minimizing the effect of adjacent clutter patches using an equalizer. The feasibility of the proposed method is validated through simulation, wherein the results from two methods are compared in terms of the Doppler spectrum and the correlation function.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.145-156
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• 2020

In 2000 and 2018, phytosociological surveys were carried out in the forest vegetation of Mt. Yeompo, a representative isolated urban forest in Ulsan city. The trends of change in forest structure, composition, and spatial distribution were compared between years. Total percent coverage per 100 squaremeters of forest vegetation was similar, but natural vegetation showed a 9% increase. The importance of constituent species changed slightly. Specifically, Lindera erythrocarpa and Styrax japonicus showed very high growth rates of 835% and 269%, respectively. Species richness (S) and diversity (H') decreased by about 22% and 8%, respectively. Both S and H' showed slightly higher rates of decrease in artificial compared with natural vegetation. The constituent species life form spectrums were the same in 2000 and 2018 as 'MM-R5-D4-e'. The similarity (Jaccard coefficient) in the species composition of the forest vegetation was almost homogeneous at approximately 75%. The number of indicator species decreased from 16 species in 2000 to 7 species in 2018. This decrease was mostly due to a decline in herbaceous plants, such as Hemicryptophytes, Geophytes, and Therophytes, which are sensitive to disturbances. The spatial distribution of forest vegetation did not change significantly. The number of forest landscape elements (patches) increased by approximately 25% from 537 in 2000 to 721 in 2018, while the average size decreased by about 20% from 1.28 ha in 2000 to 1.03 ha in 2018.

• Progress in Medical Physics
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• v.8 no.1
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• pp.3-15
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• 1997

Adrenal chromaffin cells secrete catecholamine in response to acetylcholine. The secretory response has absolute requirement for extracellular calcium, indication that $Ca^{2+}$ influx through voltage dependent $Ca^{2+}$ channel (VDCC) is the primary trigger of the secretion cascade. Although the existence of various types of $Ca^{2+}$ channels has been explored using patch clamp technique in adrenal chromaffin cells, the contribution of different types of $Ca^{2+}$ channels to catecholamine secretion remains to be established. To investigate the quantative contribution of different types of $Ca^{2+}$ channels to cate-cholamine secretion, $Ca^{2+}$ current($I_{Ca}$) and the resultant membrane capacitance increment($\Delta{C}_{m}$) were simultaneoulsy measured. Software based phasor detector technique was used to monitor $\Delta{C}_{m}$. After blockade of L type VDCC with nicardipine (1$\mu$M), $I_{ca}$ was blocked to 43.85$\pm$6.72%(mean$\pm$SEM) of control and the resultant ㅿC$_{m}$ was reduced ot 30.10$\pm$16.44% of control. In the presence of nicardipine and $\omega$-conotoxin in GVIA(l$\mu$M), an N type VDCC antagonist, $I_{ca}$ was blocked to 11.62$\pm$2.96% of control and the resultant $\Delta{C}_{m}$ was reduced to 26.13$\pm$8.25% of control. Finally, in the presence of L, N, and P type $Ca^{2\pm}$ channel antagonists(nicardipine, $\omega$-Conotoxin GVIA, and $\omega$-agatoxin IVA, respectively), $I_{ca}$ and resultant $\Delta{C}_{m}$ were almost completely blocked. From the observation of parallel effects of $Ca^{2+}$ channel antagonists on $I_{ca}$ and $\Delta{C}_{m}$, it was concluded that L, N, and also P type $Ca^{2+}$ channels served and $Ca^{2+}$ source for exocytosis and no difference was observed in their efficiency to evoke exocytosis amost L, N, and P type $Ca^{2+}$ channels.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1348-1358
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• 2017

To enhance the physiological activity of the Rhynchosia volubilis (RV), R. volubilis (RVHE-A) and R. volubilis-added herbal powder (RVHE-B) were fermented with a solid state culture of Hericium erinaceum mycelia (HE). The total isoflavone contents of the non-fermented RV-A ($489.9{\mu}g/g$) and RV-B ($571.1{\mu}g/g$) were remarkably increased in fermented RVHE-A ($1,836.4{\mu}g/g$) and RVHE-B ($1,276.7{\mu}g/g$). In particular, aglycone isoflavones such as daidzein and genistein were significantly higher in the RVHE-A than any other sample. When hot-water (HW) and EtOH extracts (E) were fractionated from the RV and RVHE, both extracts from the RVHE-A were higher than those from the RV-A in total polyphenol and flavonoid contents. However, the RVHE-B-HW showed a lower polyphenol and flavonoid content level than did RV-B-HW. RVHE-A-HW and -E also had more potent ABTS radical scavenging activity than any extract from the non-fermented RV and other ferments (RVHE-B). In the meanwhile, RVHE-A-HW potently stimulated the production of macrophage activation-related cytokines such as $TNF-{\alpha}$, IL-6 and IL-12 ($841.7{\pm}71.3pg/mL$, $3.9{\pm}0.1ng/mL$, $179.3{\pm}30.2pg/mL$) from peritoneal macrophage more than RV-A-HW ($92.5{\pm}1.5pg/mL$, $0.1{\pm}0.0ng/mL$, $37.4{\pm}5.4pg/mL$) as well as RVHE-B-HW ($557.0{\pm}21.3pg/mL$, $1.8{\pm}0.0ng/mL$, $90.0{\pm}10.0pg/mL$). However, all the EtOH extracts did not show significant activity. In addition, the RVHE-A-HW showed a significantly higher intestinal immune system modulating activity through Peyer's patch and GM-CSF production than did any other extract from RV and RVHE-B. In conclusion, these results suggest that the fermented R. volubilis with H. erinaceum mycelia possesses a possible use as an industrial application as functional food or material.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.485-495
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• 2001

It was investigated whether $Ca^{2+}$ and $K^+$ channels were involved in the inhibitory action of nitric oxide (NO) on the contractile and slow wave activity of guinea pig gastric antral circular muscle. The gastric antral circular muscle showed spontaneous phasic contraction and slow wave. NO donors, 3-morpholinosydnonimine hydrochloride (SIN-1, $0.01{\sim}100{\mu}M$) and S-nitroso-L-cysteine (CysNO, $0.001{\sim}10{\mu}M$), reduced not only the amplitude of phasic contraction but also that of slow wave in a concentration-dependent manner. Both the perfusion of $Ca^{2+}$-free solution and the administration of $Ni^{2+}$, a nonselective $Ca^{2+}$ channel blocker, reduced the phasic contraction as well as the amplitude and frequency of the slow wave. The effects of these treatments were similar to those of NO donors. Nifedipine ($10{\mu}M$), a specific L-type $Ca^{2+}$ channel blocker, abolished the phasic contraction and remarkably reduced the plateau of slow wave but had no profound effect on the upstroke of slow wave. In the whole-cell patch clamp mode, CysNO shifted the steady-state activation curve for L-type $Ca^{2+}$ current to the right and the steady-state inactivation curve to the left. Pretreatment of various $K^+$ channel blockers such as tetraethylammonium (1 mM), 4-aminopyridine (0.5 mM), glibenclamide (10 mM), apamin ($0.1{\mu}M$), and iberiotoxin ($0.1{\mu}M$) did not affect the inhibitory action of SIN-1. These results suggest that NO donors suppress mechanical and electrical activity of guinea pig gastric antral circular muscle by inhibition of L-type $Ca^{2+}$ channel rather than by activation of $K^+$ channels.

• Journal of Chest Surgery
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• v.10 no.2
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• pp.241-249
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• 1977

Atrial septal defect is one of the most frequently encountered congenital heart disease. Up to December 31, 1976, 1682 cardiac patients received cardiac catheterization in the cardiac department of Yonsei university medical college. Out of the 1682 cardiac patients 723 cases had congenital heart disease and only 116 cases had congetial atrial septal defect. This amounted to 16.04% of all those with congenital heart disease. 58 cases of congenital atrial septal defect operated in the chest surgery department were presented. Of these 58 cases of atrial septal defect, 27 cases were male and 31 cases were female. Their ages ranged from 5 years to 54 years. The systolic pressure of the main pulmonary artery of 40 out of the 58 cases of atrial septal defect was below 40% of that of the systemic blood pressure: in 6 cases, the range of the systolic pressure of the main pulmonary artery was 50-90mmHg; in 12 cases, the range of the systolic pressure of the main pulmonary artery was 40-50mmHg. Average age of these was 30. 1 years. This study tends to show that Korean patients with atrial septal defect even though younger have a slight higher systolic pressure of the main pulmonary artery than Western patients have. The pulmonary blood is 1.5-2.5 times of systemic blood flow in 52 cases out of 58 cases of atrial septal defect.In only one of the 58 cases of atrial septal defect, the Rp was found to be as high as 45% of Rs. All other cases were below this level.51 cases had ostium secundum defect, 4 out of these cases had ostium secundum defect combined with mitral incompetence and 6 out of them had double ostium secundum defect. The remaining 7 cases had ostium primum defect. Their atrial defects were repaired under direct vision utilizing extracorporeal circulation, by hemodilution technic combined with moderate hypothermia. 44 cases [2nd atrial septal defect] were repaired by direct sutures while 14 cases, including the 7 cases ostium primum defects needed patches [1 pericardium and 13 teflon patch]. In 4 cases there were single defects while showed two defects. However the associated septal defect was so small that it could be closed by direct sutures. The size of the defect ranged between 6.0cm2and 10.0cm2 in 19 cases[33.7%]: the smallest being 0. 5cm2 and the largest 24cm2. The surgical mortality was 2 cases [3.4%]. These one case with ostium primum defect, could not be resuscitated on operation table. The cause of death in this case was myocardial failure and MI. The other, a case of ostium primum defect had a second operation on the first operative day due to massive bleeding from LV vent-line insertion site.The patient died on 26th post-operative day due to sepsis.