• 한국환경복원기술학회지
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• 제19권1호
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• pp.73-83
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• 2016

Forest degradation reduces ecosystem services provided by forest and could lead to change in composition of species. In North Korea, there has been significant forest degradation due to conversion of forest into terrace fields for food production and cut-down of forest for fuel woods. This study analyzed the phenological changes in North Korea, in terms of vegetation and moisture in soil and vegetation, from March to Octorber 2013, using MODIS (MODerate resolution Imaging Spectroradiometer) images and indexes including NDVI (Normalized Difference Vegetation Index), NDSI (Normalized Difference Soil Index), and NDWI (Normalized Difference Water Index). In addition, marginal farmland was derived using elevation data. Lastly, degraded terrace fields of 16 degree was analyzed using NDVI, NDSI, and NDWI indexes, and marginal farmland characteristics with slope variable. The accuracy value of land cover classification, which shows the difference between the observation and analyzed value, was 84.9% and Kappa value was 0.82. The highest accuracy value was from agricultural (paddy, field) and forest area. Terrace fields were easily identified using slope data form agricultural field. Use of NDVI, NDSI, and NDWI is more effective in distinguishing deforested terrace field from agricultural area. NDVI only shows vegetation difference whereas NDSI classifies soil moisture values and NDWI classifies abandoned agricultural fields based on moisture values. The method used in this study allowed more effective identification of deforested terrace fields, which visually illustrates forest degradation problem in North Korea.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.123-132
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• 2002

A numerical study was conducted to investigate the combustion phenomena of normal start and unstart processes based on ISL's RAMAC 30 experiments with different diluent amounts and fill pressures in a ram accelerator. The initial projectile launching speed was 1.8 km/s which corresponded to the superdetonative speed of the stoichiometric $H_2/O_2$ mixture diluted with 5 $CO_2$ or 4 $CO_2$. Experiments with same condition except for projectile surface material demonstrated that ignition was successful with an aluminum projectile, but no combustion was observed in case of a steel projectile. In this study, it was found that neither shock nor viscous heating was sufficient to ignite the mixture at a low speed of 1.8 km/s, as was found in the experiments using a steel projectile. However, we could succeed in igniting the mixtures by imposing a minimal amount of additional heat to the combustor section and simulate the normal start and unstart processes found in the experiments with an aluminum projectile. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations coupled with a Baldwin-Lomax turbulence model and detailed chemistry reaction equations of $H_2/O_2/CO_2$ suitable for high-pressure gaseous combustion were considered. The governing equations were discretized by a high order accurate upwind scheme and solved in a fully coupled manner with a fully implicit, time accurate integration method. The numerical results matched almost exactly to the experimental results. As a result, it was found that the normal start and unstart processes depended on the strength of gas mixture, development of shock-induced combustion wave stabilized by the first separation bubble, and its size and location.

• 한국조경학회지
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• 제30권2호
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• pp.88-94
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• 2002

This study was conducted to select suitable turfarasses for use at 2002 world cup soccer fields in Korea. A 1/1000 scale Inchon worldcup soccer dome was constructed for this research. Species and seeding rates of cool-season grasses used inside and outside the dome were Kentuck bleugrass 10g/$m^2$ (KB), Kentucky bleugrass 10g/$m^2$+ perennial ryegrass 10g/$m^2$ mixture (KB+PR) and Kentucky bleugrass 6g/$m^2$+tall fescue 14g/$m^2$+ perennial ryegrass 4g/$m^2$ mixture (KB+TF+PR). Warm-season grasses also used in this study were Zoysia japonica 'Anyangjungzii' (ZA) and Zoysia japonica 'Zenith'(ZZ) which were layed as sod. So, total 5 types of grasses were used inside and outside the dome. The rootzone was constructed by the multi-layer method(United States Golf Association method). The plots were designed by randomized block design. Cool-season grasses(KB, KB+PR, KB+TF+PR) were found to be better performers for visual rating and visual color than the zoysiagrasses(ZA, ZZ). There were no significant differences in turf performance within cool-season grasses, while ZA showed better turf performances than ZZ within zoysiagrasses. The green color was maintained for about 10 months in the col-season grasses(KB, KB+PR, KB+TF+PR) compared to about 5~6 months in the zoysiagrasses. Root length and density data revealed higher values for KB, KB+PR and KB+TF+PR compared to ZA and ZZ. Root performance of 22 was better than ZA within zoysiagrasses which was the opposite result of turf performances. There was also no significant difference between U performance inside and outside the dome. However, the decreasing tendency of turf quality inside the dome at the end of the study showed that more proper maintenance technology was needed inside the d[me. It could be concluded by this study that cool-season grasses(KB, KB+PR, KB+TF+PR) were more suitable turfgrasses than waits-season zoysiagrasses(ZA, ZZ) for use at 2002 world cup soccer fields in Korea.

• KIEAE Journal
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• 제12권2호
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• pp.93-101
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• 2012

In this study, we measured the Index of Greeness(I.O.G) and analyzed factors that affect in downtown street of Seoul. The aim of this article is to provide an ways of improving I.O.G, with an emphasis on accuracy of measurement. We utilized the autimatic measurment techniques proposed by Tonosaki to solve the problem of accuracy in measurement. The result is as follows : Firstly, the average I.O.G of Gwanghwamun Plaza is 15.76%, Jongno is 11.48% and Dasanro(from Yaksu station to Beotigogae station) is 6.36%. According to the comprehensive analysis in three reseach areas, it shows that I.O.G is intimately linked with planting method, species of trees and the presence of wall planting. Secondly, it was analyzed that grass and ground-cover planting promote I.O.G better than other method. The I.O.G of photo which contains grass is 45.47%. According to the comparative analysis between tree planting and multi-planting method, the presence of lower planting showed a difference about 8.77% of I.O.G.. From the persipective of I.O.G, tree planting with two lines is more effective than one. The difference of two ways is about 3.24%. Thirdly, it is an efficint way to use the wall planting or vertical planting in order to promote I.O.G.. In Dasanro, The I.O.G of photo which contains wall planting or vertical planting is 45.47% in contrast to the average of I.O.G. is 6.36%. Fourthly, the difference of I.O.G between broadleaf tree and needleleaf tree was larger than we thought. If look closely confined to this study, the I.O.G of street planted by Pine is 3.61% and Eastern Sycamore Family Bottonwood is 12.55%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.368-368
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• 2008

Ion implantation has been widely developed during the past decades to become a standard industrial tool. To comply with the growing needs in ion implantation, innovative technology for the control of ion beam parameters is required. Beam current, beam profile, ion fractions are of great interest when uniformity of the implant is an issue. Especially, it is important to measure the spatial distribution of beam power and also the energy distribution of accelerated ions. This energy distribution is influenced by the proportion of mass for ion in the plasma generator(ion source) and by charge exchange and dissociation within the accelerator structure and also by possible collective effects in the neutralizer which may affect the energy and divergence of ions. Hydrogen atom has been the object of a good study to investigate the energy distribution. Hydrogen ion sources typically produce multi-momentum beams consisting of atomic ion ($H^+$) and molecular ion ($H_2^+$ and $H_3^+$). In the beam injector, the molecular ions pass through a charge-exchanges gas cell and break up into atomic with one-half (from $H_2^+$) or one-third (from $H_3^+$) according to their accelerated energy. Burrell et al. have observed the Doppler shifted lines from incident $H^+$, $H_2^+$, and $H_3^+$ using a Doppler shift spectroscopy. Several authors have measured the proportion of mass for hydrogen ion and deuterium using an ion source equipped with a magnetic dipole filter. We developed an ion implanter with 50-KeV and 20-mA ion source and 100-keV accelerator tube, aiming at commercial uses. In order to measure the proportion of mass for ions, we designed a filter system which can be used to measure the ion fraction in any type of ion source. The hydrogen and helium ion species compositions are used a filter system with the two magnets configurations.

• 한국수산과학회지
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• 제40권3호
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• pp.133-140
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• 2007

In 2006, we studied herbivore consumption rate and preference for algal species using laboratory experiments. In the no-choice feeding experiment, three herbivores (two sea urchins, Stronglyocentrotus nudus and Stronglyocentrotus intermedius and an abalone, Haliotis discus hannai) showed significantly (P<0.05) distinct preferences for four algae (Laminaria japonica, Undaria pinnatifida, Costaria costata and Ecklonia stolonifera). The alga preferred by S. nudus was L. japonica followed by U. pinnatifida, C. costata and E. stolonifera with respective daily feeding rates of $5.7{\pm}:0.85\;g,\;4.4{\pm}0.89\;g,\;3.1{\pm}0.39\;g\;and\;2.1{\pm}0.32\;g(mean{\pm}SE)$. A similar trend was found for S. intermedius. Interestingly, the herbivore consumption rates for the algae differed with or without competition. The competition stimulated the feeding activity for S. nudus, but lowered the activity for S. intermedius. The multi-choice feeding experiment confirmed that L. japonica was significantly preferred by two herbivores: S. nudus and H. discus hannai (Duncan's multiple range test, ANOVA, p<0.05).

• 한국콘텐츠학회논문지
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• 제8권4호
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• pp.108-116
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• 2008

최근 경영환경 변화의 중대한 흐름인 웹2.0 시대의 도래는 이용자의 적극적 참여와 공유, 개방을 의미하는 것으로, '인터넷의 생활화'를 진전시키며 사회 전반의 다양한 변화를 유발하고 있다. 웹2.0은 사회경제적 측면에서 다음과 같은 변화를 일으키고 있다: 1) 다품종 소량생산 경제 체제로의 전환 가속 2) 온라인 채널/정보의 소비자에 대한 영향력 증대 3) 경제사회 분야에서 다양한 소수의 힘 확대. 웹2.0은 기업 경영에 있어 다음과 같은 네 가지 주요 변화를 유발하고 있다: 1) 조직 내부가 아닌 외부로부터의 개방형 혁신 추구 2) 인터넷을 경유한 입소문 마케팅의 적극 활용 3) 기존 사업의 변신 추구 4) 개방적인 의사교환을 통한 고객과의 커뮤니케이션 강화. 기업들은 웹2.0으로 인한 사회경제적 변화를 직시하고, 기업 경영에 웹2.0을 적극 활용하여 사업 기회로 활용하여야 할 것이다.

• 대한의생명과학회지
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• 제16권4호
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• pp.213-220
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• 2010

Although an adequete intake of calcium (Ca) is recommended for the treatment and prevention of osteoporosis, the intake of Ca should be restricted because of its low rate of intestinal absorption. The purpose of this experiment was to identity the effect of the combined administration of Aquamin F (AQF) (a calcium agent) and lactic acid bacteria (LAB) on osteoporosis. Thirty ovariectomized (OVX) rats and six control rats were assigned to the following six groups, with six animals per group: sham Ca-deficient diet (Ca-D), OVX, LAB, AQF, and LAB-AQF. During the experiment, the body weight was measured; and after the experiment was completed, the serum biochemical analysis, the alkaline phosphatase, calcium, and inorganic phosphorus leves were measured. The tissue of the femur was stained and then scanned via CT. The body weight of the OVX group increased more significantly than that of the control group. The results of the bone mineral content (BMC), Bone mineral density (BMD), serum biochemical analysis and histological test on the femur epiphysis showed no difference between the OVX group and the LAB group, whereas the results of the AQF group were more significant than those of the OVX group. In particular, the LAB+AQF group showed more significant increases in the aforementioned results than the AQF group. This experiment showed that the combined administration of AQF and LAB in ovariectomized rats more significantly increased bone density than did a single administration of either AQF or LAB.

• Natural Product Sciences
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• 제20권4호
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• pp.251-257
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• 2014

Chungsimyeonja-tang (CSYJT) is an herbal decoction that consists with 12 herbal medicines. CSYJT has been shown to have anti-stress, anti-allergic and anti-oxidant effects. The aim of this study was to determine flavonoid contents in CSYJT and evaluate its protective effect against cisplatin induced nephrotoxicity using both in vitro (porcine renal epithelial cell; PK15 cell) and in vivo (Sprague Dawley rat) experiments. In the present study, thee mean contents of baicalin, wogonoside and baicalein in CSYJT were 14.65, 5.27 and 0.02 mg/g, respectively. The CSYJT extract treatment attenuated the following alteration in porcine renal epithelial (PK15) cell: the increase in reactive oxygen species (ROS), the glutathione depletion and the increase in p53 expression induced by cisplatin treatment. In the in vivo study, rats were orally treated with CSYJT extract once a day for 28 days. Five days before the last treatment, cisplatin (5 mg/kg) was intraperitoneally injected to induce acute renal failure. Increased blood urea nitrogen (BUN) and creatinine (CRE) levels after cisplatin treatment were ameliorated by pretreatment of CSYJT extract. In addition, lipid peroxidation was decreased and antioxidant enzyme (glutathione) was recovered in CSYJT pretreated kidney tissue. In histopathological examination, CSYJT pretreated group showed ameliorated pathological alteration after cisplatin injection with decreased apoptosis. Taken together, pretreatment of CSYJT could ameliorate cisplatin-induced nephrotoxicity.

• 한국환경복원기술학회지
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• 제21권5호
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• pp.81-96
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• 2018

The purpose of this study is to analyze the characteristics of vegetation changes and structures in the buffer green zone of Sihwa Industrial Complex and propose environmental, ecological and multi-functional vegetation management directions. The density of the Pinus thunbergii decreased from $23.1trees/100m^2$ in 2006 to $9.6trees/100m^2$ in 2017 due to the influence of thinning works. Its green volume increased from $0.97m^3/m^2$ to $2.02m^3/m^2$, contributing to the improvement of the atmospheric environment and promotion of biodiversity. The density of deciduous broad-leaved trees at the top maintained at $18{\sim}21trees/100m^2$. In the areas where the understory vegetation was removed, Pueraria lobata spread as an invasive plant and disturbed the forest. In the areas where the understory vegetation was not removed, various native plant species including the Rhus javanica and Celtis sinensis were introduced and contributed to the development of a forest in a multiple structure. There was a concern with the spread of Robinia pseudoacacia which developed into understory vegetation in Pinus thunbergii forest and some canopy forest. The study proposed vegetation management directions for the back, top and front side according to the physical structure of large-scale buffer green zone formed in a long linear form and the usage characteristics of adjacent land.