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Re-reading Chuncheon G5 International Design Competition from a Viewpoint of Landscape Urbanism (랜드스케이프 어바니즘의 관점으로 본 춘천 G5 국제설계경기 출품작 분석)

  • Kim Ah-Yeon;Koh Mi-Jin;Oh Hyung-Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.34 no.3 s.116
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    • pp.120-138
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    • 2006
  • A city evolves over time. It grows, transforms, and sometimes degrades. Chuncheon is at a turning point from a city souggling with regulations regarding clean water supply and a military encampment to a masterpiece city with a sustainable vision. The city is getting ready to restructure itself to become a world-famous culture and tourism complex expanding its physical boundary across the Camp Page site and absorbing Jungdo as a major tourist attraction. The landscape in the future blueprint of Chuncheon will play a great role in restructuring urban form. The regenerated in will have a new networked open space system as well as re-evaluated landscape resources. The hybrid theoretical practice called 'landscape urbanism' burgeoning in the fields between 'landscape architecture' and 'urbanism' can guide us in considering the terms of the relationship between a city and landscape when we design a future city Landscape urbanism is considered to be an effective framework by which we can diagnose the current status of a landscape in our contemporary urban design practice in Korea. This paper tries to provide a different perspective from the viewpoint of landscape urbanism to decipher the hidden implications of the social agreement on the role of landscape in urban structure by re-reading eight design proposals presented for the ChunCheon G5 international design competition based on the main principles of landscape urbanism. The G5 design competition is a great opportunity to test out new ideas on a city, demonstrating the relative values among various urban-design professional realms. First, this paper provides an overview of the main ideas of landscape urbanism based on the literature review and case studies. Second, framework categories are suggested in order to extract the explicit and implicit ideas on the landscape. Third, eight proposals are reviewed according to the suggested categories to situate the current landscape design of Korea within the mainstream of contemporary practice of landscape urbanism. Based on the review of eight proposals, the following diagnostic conclusions are made; first, the ideas of landscape urbanism have not been actively introduced in large-scaled urban landscape projects in Korea like Chuncheon G5. Second, it remains to be a big task for landscape professions to be able to participate in design consortiums on an equal footing. Third, In order to introduce and reify the ideas of landscape urbanism in Korea, it is inevitable and critical to test the ideas in both academic fields and professional practices to find the appropriately adjusted model of landscape urbanism.

Study on Conversion of Carbon Dioxide to Methyl Alcohol over Ceramic Monolith Supported CuO and ZnO Catalysts (세라믹 모노리스에 담지된 CuO와 ZnO계 촉매에 의한 이산화탄소의 메탄올로의 전환에 관한 연구)

  • Park, Chul-Min;Ahn, Won-Ju;Jo, Woong-Kyu;Song, Jin-Hun;Kim, Ki-Joong;Jeong, Woon-Jo;Sohn, Bo-Kyun;Ahn, Byeong Kwon;Chung, Min-Chul;Park, Kwon-Pil;Ahn, Ho-Geun
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.1
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    • pp.97-104
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    • 2013
  • Methyl alcohol is one of the basic intermediates in the chemical industry and is also being used as a fuel additive and as a clean burning fuel. In this study, conversion of carbon dioxide to methyl alcohol was investigated using catalytic chemical methods. Ceramic monoliths (M) with $400cell/in^2$ were used as catalyst supports. Monolith-supported CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using ICP analysis, TEM images and XRD patterns. The catalytic activity for carbon dioxide hydrogenation to methyl alcohol was investigated using a flow-type reactor under various reaction temperature, pressure and contact time. In the preparation of monolith-supported CuO-ZnO catalysts by wash-coat method, proper concentration of precursors solution was 25.7% (w/v). The mixed crystal of CuO and ZnO was well supported on monolith. And it was known that more CuO component may be supported than ZnO component. Conversion of carbon dioxide was increased with increasing reaction temperature, but methyl alcohol selectivity was decreased. Optimum reaction temperature was about $250^{\circ}C$ under 20 atm because of the reverse water gas shift reaction. Maximum yield of methyl alcohol over CuO-ZnO/M catalyst was 5.1 mol% at $250^{\circ}C$ and 20 atm.

Analytical Method of Bentazone Residue in Agricultural Commodities Using HPLC-UVD/MS (HPLC-UVD/MS를 이용한 농산물 중 bentazone의 분석법 확립)

  • Kim, Young-Hak;Lee, Su-Jin;Song, Lee-Seul;Hwang, Young-Sun;Lee, Young-Deuk;Choung, Myoung-Gun
    • The Korean Journal of Pesticide Science
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    • v.15 no.2
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    • pp.149-159
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    • 2011
  • Bentazone is benzothiadiazole group herbicide, and used to foliage treatment. This herbicide have already been widely used for cereals and vegetables planting in worldwide. This experiment was conducted to establish a determination method for bentazone residue in crops using HPLC-UVD/MS. Bentazone residue was extracted with acetone (adjusted pH 1 with phosphoric acid) from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover bentazone from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The bentazone was quantitated by HPLC with UVD, using a YMC ODS AM 303 ($4.6{\times}250$ mm) column. The crops were fortified with bentazone at 3 levels per crop. Mean recovery ratio were ranged from 82.0% for a 0.2 mg/kg in apple to 97.9% for a 0.02 mg/kg in Chinese cabbage. The coefficients of variation were ranged from 0.5% for a 0.02 mg/kg in soybean to 9.7% for a 0.02 mg/kg in Chinese cabbage. Quantitative limit of bentazone was 0.02 mg/kg in representative five crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of bentazone in agricultural commodities.

Determination of Ametryn Residue in Agricultural Commodities Using HPLC-UVD/MS (HPLC-UVD/MS를 이용한 농산물 중 ametryn의 분석)

  • Lee, Su-Jin;Kim, Young-Hak;Song, Lee-Seul;Choung, Myoung-Gun
    • The Korean Journal of Pesticide Science
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    • v.15 no.2
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    • pp.125-133
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    • 2011
  • Ametryn is used in USA, China, and Japan, but not introduced in Korea yet. So, MRL (Maximum Residue Level), and analytical method of ametryn were not establishment in Korea. Therefore, this experiment was conducted to establish a determination method for ametryn residue in crops using HPLC-UVD/MS. Ametryn residue was extracted with acetone from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover ametryn from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The ametryn was quantitated by HPLC with UVD, using a Tosoh ODS 120T ($4.6{\times}250$ mm) column. The crops were fortified with ametryn at 2 levels per crop. Mean recovery ratio were ranged from 83.7% for a 0.2 mg/kg in soybean to 91.1% for a 1.0 mg/kg in hulled rice. The coefficients of variation were ranged from 1.2% for a 1.0 mg/kg in hulled rice to 3.6% for a 1.0 mg/kg in soybean. Quantitative limit of amatryn was 0.02 mg/kg in representative 5 crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of ametryne in agricultural commodities.

An Analysis on Applicability of Geophysical Exploration Methods to Monitoring Polymer-flooding (물리탐사 기법들의 화학공법 모니터링 적용성 분석)

  • Cheon, Seiwook;Park, Chanho;Ku, Bonjin;Nam, Myung Jin;Son, Jeong-Sul
    • Geophysics and Geophysical Exploration
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    • v.18 no.3
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    • pp.143-153
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    • 2015
  • Polymer flooding for enhancing hydrocarbon production injects into a reservoir polymer solution that is viscous. It is very important to monitor the behavior pattern of the polymer solution in order to evaluate the effectiveness of polymer flooding. To monitor the distribution of polymer solution and thus fluid substitution within the reservoir, we first construct seismic and resistivity rock physics models (RPMs), which are functions of reservoir parameters such as rocks and type of fluid, fluid saturation. For the seismic and resistivity RPMs, responses of seismic and electromagnetic (EM) tomography are numerically simulated as polymer injection, using two dimensional (2D) staggered-grid finite difference elastic modeling and 2.5D finite element EM modeling algorithms, respectively. In constructing RPM for EM tomography, three different reservoir rocks are considered: clean-sand, dispersed shale-sand, and sand-shale lamination rocks. The polymer solution is assumed to have 2 wt% of polymer as normally generated, while water is freshwater or saltwater. Further, neutron logging is also considered to check its sensitivity to polymer flooding. The techniques discussed in the paper are important in monitoring not only hydrocarbon but also geothermal reservoirs.

Numerical Study on the Performance Assessment for Defrost and De-Icing Modes (승용차의 제상 및 성에 제거 성능 평가를 위한 수치해석적 연구)

  • Kim, Yoon-Kee;Yang, Jang-Sik;Kim, Kyung-Chun;Ji, Ho-Seong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.2
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    • pp.161-168
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    • 2011
  • The heating, ventilating, air conditioning (HVAC) system is a very important part of an automotive vehicle: it controls the microclimate inside the passenger's compartment and removes the frost or mist that is produced in cold/rainy weather. In this study, the numerical analysis of the defrost duct in an HVAC system and the de-icing pattern is carried out using commercial CFX-code. The mass flow distribution and flow structure at the outlet of the defrost duct satisfied the duct design specification. For analyzing the de-icing pattern, additional grid generation of solid domain of ice and glass is pre-defined for conductive heat transfer. The flow structure near the windshield, streakline, and temperature fields clearly indicate that the de-icing capacity of the given defrost duct configuration is excellent and that it can be operated in a stable manner. In this paper, the unsteady changes in temperature, water volume fraction, and static enthalpy at four monitoring points are discussed.

Improvement of Takju Quality by a Ripening-Fermentation Process Using Honey and Extension of Shelf Life by Control of Takju Mash Sediment (벌꿀을 이용한 고액분리 숙성 탁주의 주질 향상과 고형분의 조절에 따른 품질유지기간 증대)

  • Jung, Seung-Jin;Shin, Tai-Sun;Kim, Jin-Man
    • Journal of Life Science
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    • v.22 no.1
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    • pp.80-86
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    • 2012
  • This study was conducted to improve quality of takju where natural honey is used to control the ripening fermentation and the amount of sediment derived from takju mash. A koji was prepared using rice starch and Aspergillus awamori var. kawachii. Takju mash was prepared by alcohol fermentation with Saccharomyces cerevisiae and a 3-step addition of steamed rice. The clean part of the mash (CPM) was separated from the sediment at $5^{\circ}C$ and 5% (w/v) of natural honey was added and then ripened for 23 days at 5, 10, or $15^{\circ}C$. Temperature, pH, acidity, and total sugar content showed no significant differences, but a 0.2 percent reduction in alcohol content occurred during storage. However, CPM ripened with honey had a comparatively higher score on sensory evaluation than did immature CPM with added honey added. Takju with 8% alcohol content was prepared by mixing the water from the mixed CPM ripened with honey together with 100, 50, and 25% of the frozen sediment. Several quality characteristics of the takju were checked over 37 days of fermentation at $10^{\circ}C$. The pH was sustained between 4.1 and 4.3, and changes in the number of viable yeast cells, acidity, total sugar amounts, and alcohol content showed similar patterns but differences in scale. Smaller amounts of sediment affected the stability of the takju. Mixing the CPM ripened with natural honey at low temperature moderately reduced the amount of sediment in the mash and resulted in a highly flavorful takju with an extended shelf life.

Effects of Supplementing Different Combinations of Nitrogen Supplements on Digestibility and Performance in Sheep Fed Wheat Straw Diets

  • Li, Yong;Li, Defa;Xing, Jianjun;Li, Shengli;Han, Yang;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.10
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    • pp.1428-1432
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    • 2002
  • Thirty-six (20 wethers and 16 rams) adult Gansu highland finewool sheep with an average liveweight of $19.42{\pm}1.83kg$ were used. The sheep were allocated to 4 treatments and confined in individual feeding stalls. The 80 day feeding trial was divided into 2 periods of 38 and 42 days. The sheep had access to clean water and were fed chopped wheat straw ad libitum. Daily supplemented diets of 150 g for the first period and 200 g for the later period were provided. The 4 types of supplements were: Wheat bran type (I), which is the traditional feeding practice in the area and the control group; Linseed cake type (II); Linseed cake+poultry litter type (III); Poultry litter+distiller grains type (IV). The digestibility trial was conducted using a total collection method at the end of the first period in the feeding trial. The results showed that the digestibilities of DM, OM, CP, CF, NDF and ADF in group II and III were increased to more than 50%. CP and NDF digestibility in group II were significantly increased by 23.6% and 25.5% respectively over group I (p<0.01) and by 10.1% and 13.1% respectively over group III (p<0.05). The digestibility of DM, OM, CP, CF, NDF and ADF in group IV was lower than group I by 4.4 to 8.4% (p>0.05). Compared to group I, group II and III increased straw intake by 17.6% (p<0.01) and 10.8% (p<0.05). The ADG increased from 16.2 g in group I to 45.3 g and 32.8 g (p<0.01) in group II and III respectively. The ratio of supplement intake to gain decreased from 10.7 in group I to 3.9 and 5.4 (p<0.01) in group II and III respectively. The ratio of supplement cost to gain also decreased by 60.0% and 64.3%, respectively. The wool growth rate and wool strength in these 2 groups were noticeably improved. This significantly enhanced the wool's textile value. The above parameters in group IV were lower than in group I, except the ratio of supplement cost to gain. This research indicates that local low quality nitrogen resources could be used effectively and economically to improve the utilization of wheat straw fed to sheep on smallholder farms under harsh loess plateau conditions in the winter.

Numerical simulation of gasification of coal-water slurry for production of synthesis gas in a two stage entrained gasifier (2단 분류층 가스화기에서 합성가스 생성을 위한 석탄 슬러리 가스화에 대한 수치 해석적 연구)

  • Seo, Dong-Kyun;Lee, Sun-Ki;Song, Soon-Ho;Hwang, Jung-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.417-423
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    • 2007
  • Oxy-gasification or oxygen-blown gasification, enables a clean and efficient use of coal and opens a promising way to CO2 capture. The coal gasification process of a slurry feed type, entrained-flow coal gasifier was numerically predicted in this paper. The purposes of this study are to develop an evaluation technique for design and performance optimization of coal gasifiers using a numerical simulation technique, and to confirm the validity of the model. By dividing the complicated coal gasification process into several simplified stages such as slurry evaporation, coal devolatilization, mixture fraction model and two-phase reactions coupled with turbulent flow and two-phase heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. The influence of turbulence on the gas properties was taken into account by the PDF (Probability Density Function) model. A numerical simulation with the coal gasification model is performed on the Conoco-Philips type gasifier for IGCC plant. Gas temperature distribution and product gas composition are also presented. Numerical computations were performed to assess the effect of variation in oxygen to coal ratio and steam to coal ratio on reactive flow field. The concentration of major products, CO and H2 were calculated with varying oxygen to coal ratio (0.2-1.5) and steam to coal ratio(0.3-0.7). To verify the validity of predictions, predicted values of CO and H2 concentrations at the exit of the gasifier were compared with previous work of the same geometry and operating points. Predictions showed that the CO and H2 concentration increased gradually to its maximum value with increasing oxygen-coal and hydrogen-coal ratio and decreased. When the oxygen-coal ratio was between 0.8 and 1.2, and the steam-coal ratio was between 0.4 and 0.5, high values of CO and H2 were obtained. This study also deals with the comparison of CFD (Computational Flow Dynamics) and STATNJAN results which consider the objective gasifier as chemical equilibrium to know the effect of flow on objective gasifier compared to equilibrium. This study makes objective gasifier divided into a few ranges to study the evolution of the gasification locally. By this method, we can find that there are characteristics in the each scope divided.

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Study on Fish Diversity by Impervious Cover of Gyeongan-Stream Watershed (경안천 유역의 불투수면에 따른 어류다양성 연구)

  • Choi, Sun Hee;Kwon, Sun Soon;Lee, Sang Don
    • Journal of Wetlands Research
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    • v.14 no.4
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    • pp.561-569
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    • 2012
  • This study estimates landscape indices of the Gyeongan-stream watershed from 1975 to 2000 by classifying the land cover into impervious cover and pervious cover depending on its state using a landscape analysis program. For the indicator of biodiversity this study uses Total Core Area(TCA) among landscape indices. The estimated TCA is then used along with an Impervious Cover Model(ICM) to compare the number of fish species that appear in the Gyeongan-stream watershed. In the relations between TCA and the impervious cover ratio, it has been found that as the impervious cover ratio increases, TCA decreases accordingly. It shows that as the ratio of impervious cover in the landscape increases due to urbanization and development, the critical area that individual species need for isolation from outside has decreased. Also, the monitoring of the number of fish species that appear in the Gyeongan-stream watershed shows that in the areas with low impervious cover ratio there are more fish species appearing that inhabit in clean, uncontaminated water. It has been identified that the Gyeongan-stream watershed falls into the category of Impacted Stream and that its state is worsening, and since the watershed in this area responds to the impervious cover ratio very sensitively, its fish diversity it is required to improve the state of the basin through its proper and careful management.