• Economic and Environmental Geology
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• v.28 no.3
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• pp.259-269
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• 1995

Column leaching tests were conducted using fresh and weathered pulverised fuel ash of some 17 and 40 years old from two major British power plants, with deionised water and simulated synthetic industrial leachate. The former was to see the leaching behaviour of weathered ash and the latter was to see if the formation of secondary products from water and PFA interaction and ameliorating effect in removing metals from industrial leachates. Fresh PFA liberates elevated concentrations of surface-enriched inorganics, including Ca, Na, K, B, $Cr_{total}$, Li Mo, Se and $SO^{2-}_4$. This might indicate their association with the surface of PFA particles. In the column leaching tests using weathered ash and deionised water, elements are not readily leached but are released more slowly, showing relatively constant concentrations. For the case of weathered ash, some readily soluble surface-enriched elements appears to have been liberated in their early stage of leaching and the liberation of glass associated elements are thought to be more important function in controlling the element concentration. The result from column leaching tests exceed for a number of elements when compared with various Water Standards and suggests the leachate from PFA disposal mound needs dilution to achieve target concentrations. PF A shows element retention effect for many elements, including B, Fe, Zn, Hg, Ni, Li and Mo, in the order of fresh Drax ash > weathered Drax ash > Weathered Meaford ash in retaining capacity. Geochemical modelling using a computer program WATEQ4F reveals some solubility controlling secondary solid products. These include $CaSO_4{\cdot}2H_2O$ for Ca, $Al(OH)_3$ for Al and $Fe(OH)_3$ for Fe.

• Proceedings of the Korean Society of Community Living Science Conference
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• 2009.09a
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• pp.99-99
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• 2009

지명(地名)은 그 지역의 역사와 전설, 문화, 풍속은 물론 독특한 자연환경이나 생활 모습을 담고 있어 농업농촌의 지역적 특성을 나타낸다. 본 연구는 지명유래의 활용성 증진의 한 방편으로 브랜드 및 문화관광상품 개발을 위해 서천군의 자연마을 지명유래, 이미지, 관광자원 등을 조사하였다. 서천군의 자연마을 유래 516건에 대한 자료는 국토지리정보원, 문화원자료집, 서천군홈페이지에서, 산, 강, 골, 고적, 못 등 그 외 지명자료는 한글학회 지명총람에서 2,000건을 수집하였다. 자연마을지명의 유래 516건을 8개 유형으로 구분하면 자연지리 122건, 인문지리 114건, 생태환경 51건, 산업경제 25건, 역사 34건, 유적유물 28건, 민속 37건, 종교 19건이며, 지형(80건), 생물(33건), 고사(19건)관련 유래가 많았다. 서천군 지역브랜드 개발을 위한 요구도 조사는 지역민 154명과 방문객 152명 총 306명을 조사하여 SPSS WIN 12.0 프로그램을 이용 분석하였다. 응답자의 일반적 특성은 여성이 55.6%, 대졸자 54.2%, 연령은 40대(29.1%), 1500만원-3000만원 미만의 연소득자 32.0%가 가장 많았다. 서천군의 형용사적 이미지를 기술통계량으로 살펴보면 지역민은 평화로운, 정감있는, 순수한, 전통적인, 믿을수 있는 순으로, 방문객은 순수한, 평화로운, 정감있는, 따뜻한, 친절한 순으로 평균간이 높게 나타났고, 요인분석에 의한 지역민과 방문객의 인지적 형용사 도출결과는 정열적, 평화적, 보수적인 3가지 요인이다. 또한 서천군의 대표적 상징자원은 지역민의 경우 춘장대해수욕장(32.5%), 희리산 자연휴양림(16.9%), 금강하구둑 철새도래지(16.9%)순이며, 방문객은 춘장대해수욕장(43.4%), 희리산 자연휴양림(23.0%), 한산모시축제(23.0%)순으로 높게 나타났고, 지명 호감도는 지역민의 경우 꽃뫼(29.2%), 솔리(20.8%). 소야(17.5%)순이며, 방문객은 꽃뫼(30.9%), 솔리 (19.7%), 무닛골(16.4%)순으로 높았다. 향후 본 연구에서 제시된 연구를 통하여 서천군의 지명을 활용한 브랜드개성을 측정할 수 있어 마케팅 관점에서 서천군의 브랜드를 도출하는데 기여할 수 있을 것이다.

• Fire Science and Engineering
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• v.28 no.6
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• pp.52-57
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• 2014

The present study suggests the fundamental method for the prediction time of the fire origin by analyzing the combustion phenomenon of inflammable material in the building structure. The heat release rate (HRR) with time variant is evaluated for the interphone as a inflammable material, which is opted from the fire incidents in the stairwell. the fire dynamics simulator (FDS ver. 6.1) is applied in order to analyze the difference of the smoke inflow time to the downstair from the fire event area with various fire pattern. The results show that the maximum inflow time difference for the case of the interphone made from ABS materials is about 4.93 times with the input conditions of heat flux values and the environment in the FDS for the fixed stairwell which composed of total volume $291.3m^3$, floorage $23.3m^2$ and the height of each floor 2.5 m. This research can be practical information for the application method of simulation scheme with experimental data to the fire Identification.

• Journal of the Korean Institute of Gas
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• v.19 no.2
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• pp.29-36
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• 2015

This study is an 1-D numerical study prior to modification of diesel engine for power plants to natural gas/diesel dual fuel engine using GT-Power with 1.5MW diesel engine for power generation. Natural gas injector was installed to intake manifold for dual fuel engine model. Effects on engine performance and characteristics were investigated when dual fuel is used in unmodified diesel engine. The analysis was done under 5 conditions from 0% to 40% of mixing rate on 720RPM engine speed. As a result of research, the engine performance was decreased as increasing ratio of natural gas. Engine brake power was decreased by 18.4% under 40% mixing rate condition. To clarify the reason, effects of injection timing and period were evaluated with DOE method. Considering this result, optimization was done for these parameters. Also, comparison between performances of dual fueled engine and diesel engine was made after optimizing the timing of injection by DOE method. As a result, engine brake power was decreased by 8.55% under mixing rate 40% condition showing 12.5% improvement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.725-731
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• 2016

This study numerically investigates the thermal performance of a 2.0-kW butane-based combustion heating system for an electric vehicle under cold conditions. The system is used for cabin space heating and coolant-based battery thermal management. ANSYS CFX 17 software was used for parametric analysis. The mass flow rates of cold air and coolant were varied, and their effects were compared. The numerical results were validated with theoretical studies, which showed an error of 0.15%. As the outside air mass flow rates were increased to 0.005, 0.01, and 0.015 kg/s, the cabin supply air temperature decreased continuously while the coolant outlet temperature increased. When the coolant mass flow rates were increased to 0.005, 0.01 and 0.015 kg/s, the air temperature increased while the coolant outlet temperatures decreased. The optimal mass flow rates are discussed in a consideration of the requirements for high cabin heating capacity and efficient battery thermal management.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.37-43
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• 2019

This research studied production of lightweight filling production for sink hole restoration utilizing various industrial by-products(2kinds of fly ash, petro-cokes CFBC ash, blast furnace slag fine particle). For this purpose, the mixed raw material properties(compressive strength) behaviors according to the blending ratio of industrial by-products were examined by applying the experimental design method and statistical analysis was performed using the commercial program MINITAB. Compressive strengths of industrial by-products were strongly dependent on blast furnace slag powder. Compressive strength(3days aging) was 3~11MPa depending on the amount of blast furnace slag powder used. The use of CFBC fly ash was evaluated to have the least effect on compressive strength. In addition, the compressive strength and the coefficient of permeability were measured by preparing foamed concrete for the experimental batch 1 condition in the mixture experimental design. In this case, the bulk density is 0.9 to 1.0, the apparent porosity is 30 to 50%, the compressive strength(3days old) is 1 to 2MPa, and the permeability coefficient is $10^{-2}$ to $10^{-3}cm/sec$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.705-715
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• 2010

The adoption of carbon foot print system is being activated mostly in the developed countries as one of the long-term response towards tightened up regulations and standards on carbon emission in the agricultural sector. The Korean Ministry of Environment excluded the primary agricultural products from the carbon foot print system due to lack of LCI (life cycle inventory) database in agriculture. Therefore, the research on and establishment of LCI database in the agriculture for adoption of carbon foot print system is urgent. Development of LCA (life cycle assessment) methodology for application of LCA to agricultural environment in Korea is also very important. Application of LCA methodology to agricultural environment in Korea is an early stage. Therefore, this study was carried out to find out the effect of lettuce cultivation on agricultural environment by establishing LCA methodology. Data collection of agricultural input and output for establishing LCI was carried out by collecting statistical data and documents on income from agro and livestock products prepared by RDA. LCA methodology for agriculture was reviewed by investigating LCA methodology and LCA applications of foreign countries. Results based on 1 kg of lettuce production showed that inputs including N, P, organic fertilizers, compound fertilizers and crop protectants were the main sources of major emission factor during lettuce cropping process. The amount of inputs considering the amount of active ingredients was required to estimate the actual quantity of the inputs used. Major emissions due to agricultural activities were $N_2O$ (emission to air) and ${NO_3}^-$/${PO_4}^-$ (emission to water) from fertilizers, organic compounds from pesticides and air pollutants from fossil fuel combustion in using agricultural machines. The softwares for LCIA (life cycle impact assessment) and LCA used in Korea are 'PASS' and 'TOTAL' which have been developed by the Ministry of Knowledge Economy and the Ministry of Environment. However, the models used for the softwares are the ones developed in foreign countries. In the future, development of models and optimization of factors for characterization, normalization and weighting suitable to Korean agricultural environment need to be done for more precise LCA analysis in the agricultural area.