• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.147-154
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• 2004

The purpose of this paper is to improve the existing phase split algorithm considering the minimum green time in COSMOS. In the case of a signalized intersection where two wide and narrow streets intersect each other, the time required for the pedestrian crossing is frequently longer than the time alloted to the through traffic on a minor street. In order to meet the minimum green time requirement for the pedestrian less time in alloted automatically to the left-turn traffic, creating heavy congestion on the left-turn approach. To solve this problem, this study suggests a new algorithm which shares the barrier using minimum green time and shares the burden with signal phases alloted to the crossing street traffic on the basis of the equal ratio of the degree of saturation, while maintaining the minimum green time requirement. The new algorithm was compared with the existing algorithm by using a microscopic simulation model for COSMOS evaluation developed at Ajou University. The simulation results show that the new algorithm produces better performance than the existing one.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.5
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• pp.470-498
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• 2022

Recently, the world has been considering hydrogen energy as the primary energy transition means to achieve carbon neutrality by 2050. In order to achieve the goal of reducing greenhouse gas emissions, Korea is also promoting a clean hydrogen economy. However, it is necessary to introduce various clean hydrogen from overseas so that the projected demand can not meet the domestically produced. For this study, we conducted the policy comparison approach between countries other than the generally considered technical and economic approaches. The finding proposes the direction of bilateral cooperation for a strategy of securing overseas clean hydrogen from a geopolitical perspective. Germany was a target country for the policy comparison since it has a high proportion of manufacturing, like Korea, and is taking the lead in the renewable-based energy transition policy. According to the survey and analysis of the policy establishment status and new projects of the two countries, Germany is promoting bilateral international cooperation in the hydrogen area with about 33 countries based on 7 types of activities. In comparison, Korea is involved in bilateral cooperation with about 12 countries on relatively few activities. Among the types of bilateral cooperation, R&D cooperation with advanced countries for hydrogen technology was a common activity type. Germany preemptively promotes cooperation for demonstration and commercialization, considering geopolitical means and strengthening manpower training and assistance on policy and regulation to preoccupy the market for the future. Therefore, it is necessary to consider establishing a network of an entire life cycle of supply and demand network that links the future market with securing clean hydrogen considering the geopolitical distribution. To this end, Korea also needs to expand bilateral cooperation countries by activity type, and it seems necessary to seek various geopolitical-based bilateral cooperation and support measures for developing countries to diversify the supply sources of hydrogen.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.1-4
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• 1972

Since Kanda's paper on Korean scale insects in 1942, no work on scale insects has been done in Korea. The author has collected 8 species of scale insects in 5 green houses in Seoul and Suwon, of which 4 species, i.e., Chionaspis kentiae, Chrysomphalus aonidum, Planococcus kraunhiae and Aspidiotus hederae are new to Korea. Dominant species were Planococcus citri and Coccus hesperidum and common species to 4 green houses were Planococcus citri, Coccus hesperidum and Saissitia coffeae.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.256-258
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• 2011

Using the axial Green's function method for Steady Stokes flows, we introduce a new pressure correction formula to satisfy the incompressibility condition, in which the pressure is related to the integral of the second order derivatives of the velocity. Based on this formula, we propose the iterative method for solving the Stokes flows in complicated domains. Even if the domain is complex, this method maintains the second order of convergence for the velocity.

• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.167-178
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• 2007

This paper deals with the solutions of linear inhomogeneous time-fractional partial differential equations in applied mathematics and fluid mechanics. The fractional derivatives are described in the Caputo sense. The fractional Green function method is used to obtain solutions for time-fractional wave equation, linearized time-fractional Burgers equation, and linear time-fractional KdV equation. The new approach introduces a promising tool for solving fractional partial differential equations.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.568-571
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• 2011

A new poinsettia cultivar 'Green Dream' was bred by the National Institute of Horticultural and Herbal Science (NIHHS) in 2009. A cross was made between 'Lemon Snow', a variety with dark green leaves and light yellow-green bracts, and 'Freedom Rose', a variety with vigorously growing deep pink bracts in 2006. 'Green Dream' was finally selected in 2009 after the investigation of the growth and flowering characteristics from 2007 to 2009. 'Green Dream' has light yellow-green ovate bracts and medium intensity of rugosity between bract veins. Leaf blade is ovate and dark green. Petiole length is long, and stem color is greenish. 'Green Dream' has medium free-branching ability and long plant height. 'Green Dream's bracts and transitional leaves are fully colored 7 weeks after short day commencement.

• KIEAE Journal
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• v.15 no.2
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• pp.5-17
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• 2015

Purpose: The goal of this research is to identify the planning techniques of Smart Green City with Ubiquitous method and carbon-neutral city planning techniques and to induce the main planning techniques through the analysis of relative importance and practical adaptation. Method: First of all, eighteen planning techniques were derived and categorized into three organization systems and six sectors through literature review and FGI analysis considering the applicability of Ubiquitous service for carbon-neutral city planning techniques. Secondly, based on expert surveys and AHP analysis, the importance of Smart Green City planning techniques was evaluated. Thirdly, using case study, six cases related to Smart Green City were analyzed for the current status of application of planning techniques. Lastly, considering the importance of planning techniques and practical aspects, the characteristics of Smart Green City and its implication were estimated. Result: Energy, Resource and Waste and Transportation sector were identified as important sectors for Smart Green City. In addition, 'Construction of Smart Grid', 'System for Utilization of New & Renewable Energy', 'Smart Resource Circulation Management System', 'Establishment of Public Transportation Information System basis', 'Construction of Pedestrian / Bicycle oriented Road Environment' are essential planning techniques to create Smart Green City.

• The Journal of Natural Sciences
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• v.18 no.1
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• pp.65-76
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• 2007

The purpose of this study is to examine residents' consciousness for urban parks and green spaces in the city of Daejeon. This work enables us to find new implementation factors to increase resident's satisfaction of urban parks and green spaces. This study surveyed 1005 residents from 80dongs(neighborhoods), of 5 Gu(districts) districts in Daejeon. The survey was conducted with a structurally organized questionnaire and objective materials. The data collected from participants of the survey were summarized as follows. Daejeon residents want more natural parks and neighborhood parks than other urban facilities as recreation facilities. The favorite places in which Daejeon residents visit are Bomun Mountain, Gap River, Geajock Mountain, and Yudeon River, in order. In landscape scenery of Daejeon, residents prefer Daedeck research complex area than others and they felt that urban landscape scenery is more improved than 5 years ago. Also they want to increase the area of park and green space about 4times more than present. The result shows that the importance index of park and green space is 8.7 and the satisfaction index is 5.42. These results suggests that the demand by residents for urban park and green spaces will improve as the urban structure is improved.

• Korean Journal of Construction Engineering and Management
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• v.14 no.3
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• pp.97-106
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• 2013

The construction industry is now facing a new challenge of green construction. Based on a research question of "what motivates contractors to pursue green construction", the objective of this study is to identify and discuss key characteristics and implications of green construction motivators among major contractors. The Political Economy Approach was adpoted as a main research methodology. The study demonstrated that major contractors show a high level of expectation in the future of green construction and consider economic factors as higher motivators while paying attention to social trends towards green construction. In particular, internal economic motivators were highly considered and the commitment of senior management was viewed as a key motivator.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.5
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• pp.41-51
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• 2022

Carbon neutrality is emerging as a new paradigm for the international society by transiting from climate change to climate risk. This study proposes evaluation methods for the carbon reduction contribution of climate-related national R&D projects in order to introduce a green budget system in the agricultural sector. We considered the domestic and foreign green budget systems and classified national R&D projects into positive, negative, and neutral from the perspective of carbon reduction. The results of this study propose three methods to estimate the monetary costs and carbon benefits by adopting the framework for the economic evaluation of national R&D projects conducted by the Rural Development Administration. These methods support to evaluate the potential contribution to carbon reduction of national R&D projects in the agricultural sector. Finally, the proposed methods were tested and verified for the efficiency and validity of evaluating carbon reduction contribution. These evaluation methods of the carbon reduction contribution can be used as a basic methodology for the pre-budget calculations of national R&D projects and the contribution for the greenhouse gas reduction budget.