• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.125-134
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• 2012

This study is determined by tree vigor of analyzing of each object's growth condition in Locational Characteristics and compare the result with impediment extent rate in crown area to provide the management Study about the influence of man-made structures in numbers of protected trees. 68 places where are in the list of Kimpo protected trees were researched in Natural environments, vital degree of trees, number of trees. Crown area was calculated surveying it around the directions of North, East, South and West branching out. Impediment in the area was analyzed after classified into artificial impediment like paved surface(ascon, concrete, block, etc.), a building and a breast wall and natural impediment like soil, stonework and gravel and conclusions are as follow. In analyzing of natural environments, he ground where protected trees have located is consist of 72.05 of manmade structure and artificial in all. There are many protected trees which have less space than crown area for growth suggested by Woo-kyung Sim and Se-kyun Shin in 1992. And it was analyzed that making growth space for protected trees and management of impediment are urgently needed because of that the proportion of impediment covering the crown area has increased as cities are becoming more urbanized results in transforming of trees and weakness of tree vigor. This research shows that under 20% of in crown area is tree vigor determination 1-2 grade 21-50% under is 2-3 grade, higher than 50% is 3-5 grade. More impediment have more difficulty for growing, with the management of root system of protected trees need to be under 20% of rate of land is necessary was improved. As follows are suggested about the standard of management in artificial impediment which influence the number of trees. Firstly, impediment in crown area must be restricted under 20%, but in case outside of the area is not artificial the rate could be higher considerable. Secondly, protected trees growth space secured as much as crown area and impediment must be installed outside the crown area. Thirdly, to move the protected trees, condition of growth space secure must be considered. Fourthly, to develope land, the area around protected trees should be utilized in a park, the area of impediment installation in crown area should be limited as well. Fifthly, As many shown in previous research, for the improvement of old big trees and protected trees, need the tax favor of landowner and purchase of around land, to manage, it needs the budget of local government and advice of expert. Also the study on how various kind of impediment nearby protected trees influence on them has to be continued.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.317-330
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• 2009

Research was initiated to investigate germination vigor, number of leaves, plant height and turfgrass density. A total of 18 treatment combinations were used in the study. Treatments were made of soil organic amendment(SOA), sand, and water-absorbing polymer. Germination vigor, leaf number, plant height and turfgrass density were evaluated in Kentucky bluegrass(KB) grown under greenhouse conditions. Significant differences were observed in germination vigor, leaf number, plant height and turfgrass density among 18 mixtures of SOA and polymer. Highest germination rate was associated with mixture of SOA 20% + sand 80% + polymer 0%, resulting in 56.3% for KB. Number of leaves at 60 DAS(days after seeding) were greater with KB over PR, while plant height higher with PR over KB. Leaf number increased with SOA, being SOA 20% > SOA 100% > SOA 10% and with polymer from 0 to 12%. Plant height was greatest with SOA 20% and lowest with SOA 100%. Greater density was observed with PR rather than KB due to longer plant height. Turf density was best under SOA 10% and poorest under SOA 100% in KB. A further research would be required for investigating the individual effect of K-SAM, Ca, perlite on the turf growth characteristics.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.57-62
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• 2003

A general procedure of obtaining reliable one-step kinetics model for hydrocarbon mixture from the fully detailed chemistry is described iin this study. One-step theoretical formulation of the induction parameter model IPM uses a theoretical reconstruction of the induction time database obtained from a detailed kinetics library. Non-dimensional induction time calculations is compared with that of detailed kinetics. The IPM was latter implemented to fluid dynamics code and applied for the numerical simulation of detonation wave propagation. The numerical results including the numerical smoked-foil record show the all the details of the detonation wave propagation characteristics at the cost around 1/100 of the detailed kinetics calculation.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.2
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• pp.165-176
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• 2015

A numerical analysis was conducted to investigate the inlet buzz and combustion oscillation in an axisymmetric ramjet engine with wedge-type flame holders. The physical model of concern includes the entire engine flow path, extending from the leading edge of the inlet center-body through the exhaust nozzle. The theoretical formulation is based on the Farve-averaged conservation equations of mass, momentum, energy, and species concentration, and accommodates finite-rate chemical kinetics and variable thermo-physical properties. Turbulence closure is achieved using a combined scheme comprising of a low-Reynolds number k-${\varepsilon}$ two-equation model and Sarkar's compressible turbulence model. Detailed flow phenomena such as inlet flow aerodynamics, flame evolution, and acoustic excitation as well as their interactions, are investigated. Mechanisms responsible for driving the inlet buzz are identified and quantified for the engine operating at subcritical conditions.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.431-434
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• 2005

A series of numerical studies are carried out for the different regimes of the detonation phenomena to investigate the computational requirements for the simulation of the cell structure of detonation wave by varying the reaction constants and grid resolutions. The computational results are investigated by comparing the solution of steady ZND structure to draw out the minimum grid resolutions and the size of the computational domain for capturing cell structures of the different regimes of the detonation phenomena.

• Journal of Information Technology Applications and Management
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• v.14 no.1
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• pp.75-97
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• 2007

Recently, the growth of the Internet shopping malls around the world has been increasingly accelerated based on the great advances of IT. Nevertheless, in China the Internet shopping malls have not rewed up relatively. Therefore, this paper has a purpose to discover the factors influencing the vigor of the shopping malls in China and mechanisms on interrelationships among the factors, focusing on customers' trust. To analyze the Chinese Internet shopping mall market from a wider perspective, our research model includes the antecedents from the aspects of shopping mall quality, customer characteristics, environmental features through reorganizing comprehensively various factors considered in the previous studies, and uses customer trust as an intermediate factor and purchasing intention as a dependent factor. It is expected that the implications of this study can help Chinese government agencies related to Internet shopping malls and managers for them make decisions on their policies and strategies effectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.103-114
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• 1994

Pearl millet is a $C_4$ plant and summer crop originated from west Africa, and the sixth most important cereal in the world and the most widely cultivated millet in the semi-arid tropics as a major staple food crop. Its grain of higher quality protein is used to make unleavened bread chapatis and prepared as gruel, dumplings, couscous and beer. It is also used as animal feed and forage in both temperate and tropical regions because it has a capability to grow well not only in the fertile soil, but also in the poor and dry soil. Most of the current breeding procedures used in pearl millet are aimed at maximum exploitation of hybrid vigor for both grain and forage yields in Korea. Pearl millet is ideally suited for exploitation of heterosis using cytoplasmic male sterile lines as seed parent, and fertile inbred lines and open-pollinated cultivars as pollen parent. Pearl millet hybrids developed in Korea produced 3 to 7 tons of grain and 100 to 150 tons of green fodder per hectare.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.391-395
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• 1999

Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.1
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• pp.9-13
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• 1979

Dihaploid lines of tobacco (Nicotiana Tabacum L.) were developed from vitro anther culture of single cross F 1, "SC 72"X "Hicks". All genetic materials were evaluated for agronomic performance and chemical composition. Compared with midparent value, pollen derived dihaploid progenies showed reduced vigor in all measured features of plant growth, and increased total alkaloids as well as decreased reducing sugar content.

• 한국전산유체공학회:학술대회논문집
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• 2000.05a
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• pp.107-112
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• 2000

연소실 안으로 분출되는 스월 유동의 vortex breakdown mechanism 에 대한 연구를 하였다. 3 차원 유한 체적기법과 Runge-Kutta 시간 적분법이 적용되었으며, 난류모델은 dynamic large eddy simulation (DLES)이 적용되었다. 계산 시간의 효율성과 기억용량을 효과적으로 사용하기 위하여 message passing interface (MPI) 병렬계산 기법이 적용되었다. 스월 난류 유동에 있어서 vortex breakdown 거동을 가시적으로 표착 하였는데. 이는 스월 유동에 의한 난류 응력 증대, 난류 생성/소산율 증대 및 혼합율 증대에 대한 실험적 근거를 뒷받침하는 매우 중요한 결과이다. 또한 평균 속도와 레이놀스 응력에 대한 계산 결과도 실험 결과와 비교하였다.