• Journal of Korean Society of Transportation
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• v.19 no.1
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• pp.29-52
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• 2001

The purpose of this paper is to pursue a case study of urban land use and transportation linkage policies based on a British city of Cardiff, Wales. To this end, the paper combines a review and synthesis of available land use and transportation planning sources, and a series of interviews with planners and a extensive survey of planning policy documents to assess the effectiveness of policy instruments in the city context. Considerable emphasis is placed on the analysis of the British land use and transportation planning in terms of the Policy guidance notes 11, 12 and 13 as well as the local transport policy guidance. The paper highlights the fact that the Cardiff unitary development plan and the local transport plan form a policy framework of integrating land use and transportation planning process, employing travel demand management schemes and implementing the various strategy components on the overall aim of achieving and maintaining a sustainable city.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.497-503
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• 1983

This study was conducted to define the effects of light intensity on the amount of saponin and free sugar and the ratio of triol group saponin and diol group saponin (PT/PD) in the leaf of Panax ginseng C.A. Meyer. 4-Year-old ginseng plants were grown under the shadings of different light transmittance rate(LTR) of 5%, 10%, 20% and 30% for 5 months and the leafiets were sampled from 2nd low at late August to determine the amount of saponin and free sugar.-Rd was main ginseuoside in the diol group saponin but in triol group saponin, ginsenoside-Re showed highest value and next was ginsenoside-$Rg_1$ and $Rg_2$ respectively. Up to 20% of light transmittance rate (LTR), the ginseng leaves grown under high light intensity showed an increase in the amount of total saponin and the ratio of PT/PD but the amount of total saponin and the ratio of PT/PD but the amount of total saponin and the ratio of PT/PD was decreased at the ginseng leaves grown under the shading of 30% LTR. The ginseng leaves grown under the shading of 20% LTR showed a significant increase in the amount of glucose and fructose but a significant decrease of sucrose content. A significant positive correlation ($r=0.992$^{**}$) was recognized between the of amount of total saponin and glucose.

• Particle and aerosol research
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• v.11 no.3
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• pp.63-75
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• 2015

Atmospheric environment in Korea is influenced by outside, especially China. The concentrations of air pollutants in China have showed decreasing trends since 2000. However, these concentration levels in China are still higher than other developed countries. The Chinese Government has tried several measures to control the air pollution. In this study, the details of the amendments and smog reduction strategies in China, especially for Beijing are reviewed and the strategies for Korean side to promote cooperation in Northeast Asia are suggested and discussed. The Chinese State Council amended the Environmental Protection Provisions and Clean Air Act and announced The Action Plan for Air Pollution Control (2013-2017), focusing on three key regions, Beijing-Tianjin-Hebei area (Jing-Jin-Ji), Yangtze River Delta (YRD) and Pearl River Delta (PRD). These policy actions and plan are mainly for the reducing coal usage and emissions from vehicles. It is suggested that, Korea should actively promote multi-national cooperation in the region to take an initiative role in environmental areas.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.1-2
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• 2011

Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.