• Journal of the Korean GEO-environmental Society
• /
• v.13 no.1
• /
• pp.31-36
• /
• 2012

Recently, industrial by-products are exponentially growing because energy consumption is increasing due to rapid industrial development and improved living standards. The purpose of this study is to determine the proper mixing ratio to meet the liner conditions(must be less than $1{\times}10^{-7}$cm/sec), using pond ash and bentonite as liner. As the result of the compaction test, depending on the increase mixing ratio of bentonite, the maximum dry unit weight was decreased but the optimum moisture content was tended to be increased at the compaction curve. As the result of the permeability test, depending on the increase mixing ratio of bentonite, the coefficient of permeability showed tendency to be decreased in the form of index and the tendency was caused by the hydration reactions filling the void of the pond ash. When the mixing ratio of bentonite was approximately over 15%, it was satisfied with the land fill liner conditions. In other words, it is necessary to consider other mixtures containing the cement or another material in the economical aspect for application of the pond ash.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.229-229
• /
• 2010

본 실험에서는 $CuInSe_2$, 3원물질을 화학량론적 조성비가 되도록 박막을 제조하기 위해 각 단위원소를 원자비에 맞춰 전자선가열 진공증착기를 사용하여 Cu, In, Se 순으로 증착하였다. $10^{-3}$torr 이상의 진공석영관에서 열처리와 동시에 Selenization을 통해 제작된 $CuInSe_2$박막은 열처리온도 $250^{\circ}C$에서는 $Cu_xSe$, CuSe등의 2차상들이 나타나다가 $450^{\circ}C$이상의 고온에서 $CuInSe_2$ 단일상을 형성하였다. 이로부터 진공중에서 반응을 시켰을 때, 더 낮은 온도에서 반응이 일어나고 열역학적으로 보다 안정한 소수의 화합물들이 쉽게 형성됨을 확인할 수 있었다. 특히 $250^{\circ}C$에서는 Sphalerite 구조를 가지다가 $350^{\circ}C$이상의 온도에서 Selenization하였을 때 Chalcopyrite 구조를 가졌다. 박막이 두꺼워지면서 결정립의 크기가 커지고 응력이 작아지는 특성을 보였다. 에너지 밴드갭은($E_g$)은 Cu/In 성분비율이 클수록 작은값을 보였으며, 결절립크기가 증대되므로 결국 흡수계수가 낮아짐을 알 수 있다. 또한 두께가 증가할수록 전반적으로 흡수계수가 증가하였고 Cu/In의 성분비율이 0.97일 때 기초흡수파장은 1,169nm이고 에너지밴드갭은 1.06eV이었으며, 두께 $1.5{\mu}m$이상일 때 전반적으로 양호한 상태의 p-type $CuInSe_2$ 박막을 제작 하였다.

• Journal of Korean Society of Forest Science
• /
• v.87 no.2
• /
• pp.286-299
• /
• 1998

This study was conducted to do a comparative analysis of hunting system in 16 OECD(Organization for Economic Co-operation and Development) countries. Hunting is one of the most advanced types for developing natural resources, esp. wildlife, which is one of major products from forest. There are two types of hunting system ; Revier and/or License System, around most countries which have traditional advanced hunting and higher hunter population. Licence system, which is chosen in Korea, is less efficient ways of hunting for maximizing economical value and wildlife management than Revier system does. Adopting better system for much more efficient economical condition from hunting in Korea in a future is a ultimate goal in this study. The first step for the goal is an analysis of these two system among 16 OECD countries ; United State, Japan, Germany, France, etc. Comparative researches in hunting regulations such as number of hunters, hunter ratio to population, hunting bags, game species, seasons, ammunition and hunting permit are a next step for adopting developed hunting system in Korea. Korea has a smallest hunter ratio to population (1/2,463) among 16 OECD centuries and economical value lead by hunting is estimated still very low. Revier system is a popular one in most OECD countries except United State, Japan, etc, which is useful for wildlife management and maximizing economical value of hunting. And usually rifles are permitted for big game hunting. Hunting examination and/or insurance are compulsory for achieving hunting permit. Depend on game species, yearly hunting bag and season are constructed in most OECD countries.

• Journal of the Mineralogical Society of Korea
• /
• v.19 no.4 s.50
• /
• pp.347-353
• /
• 2006

The atomic-nano scale structures of multi-component aluminosilicate glasses have not been well understood in spite of its implications fur dynamics and generation of magma in the natural system due to lack of suitable spectroscopic and scattering experiments. Here, we report O-17 MAS and isotropic projection of 3QMAS NMR spectra for quaternary Na-Ca silicate glasses $[(CaO)_x(Na_2O)_{1-x}]\;(A1_2O_3)_{0.5}(SiO_2)_6,\;CNAS)$ at 14.1 Tesla where atomic configurations around bridging oxygen (Si-O-Si, Si-O-Al) and non bridging oxygen (Na-O-Si, Ca-O-Si, (Na, Ca)-O-Si) are partially resolved. With increasing Na content, the fraction of Na-O-Si increases while those for bridging oxygens remain constant. The Na/Ca ratio apparently affects the peak widths of bridging oxygen peaks (e.g., Si-O-Si)) and thus the topological entropy as well as chemical shifts of the bridging oxygen peaks, implying that both BOs and NBOs are strongly interacting with network modifying cations The effect of cation field strength on the degree of Al-avoidance was also discussed.

• Journal of Korean Society of Forest Science
• /
• v.104 no.2
• /
• pp.248-253
• /
• 2015

This study applied the portfolio approach as a means to provide decision-making information for the establishment of the optimal production plan for non-timber products. The target items of non-timber forest product were Chestnut, Jujube, Walnut and Astringent Persimmon. The data used in this study were the annual report of forestry production cost survey which contains the annual production, annual gross income, and annual product cost from 2008 to 2013. These data were used to calculate the expected return of non-timber forest product. The objective function in the portfolio models was to minimize the expected return volatility, called risk and the constrain was to achieve the minimum expected return rate. Results indicated that the production ratio of the nuts and fruits in 2013 was 7% for Chestnut, 20% for Jujube, 5% for Walnut and 68% for Astringent Persimmon. Furthermore, portfolio presented that the production ratio was 10% for Chestnut, 9% for Jujube, 3% for Walnut and 78% for Astringent Persimmon in the near future. The cause was analyzed due to maintain stable production and income of Astringent Persimmon and Chestnut. Meanwhile, the revenue of Walnuts and Jujube was in great variation with relatively higher revenues.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 1999.10a
• /
• pp.187-197
• /
• 1999

해양수산부가 개발 .운영 중인 항만운영정보시스템(PORT-MIS)은 선박입출항 관련 업무, 수출입 화물 반출입에 관한 업무, 항만시설물관리에 관한 업무, 의사결정지원시스템에 관한 업무 등 크게 4개 업무오 구성되어 있으며, 총 19개의 전자문서와 1,500여개의 단위 프로그램으로 구성되어 있다. 그동안 PORT-MIS를 권역별로 확대 운영하면서 발생한 여러 가지 문제점들을 보완하기 위해 해양수산부와 정보통신부(한국전산원)가 공동으로 $\ulcorner$수출입화물 일괄처리시스템 구축$\lrcorner$ 용역 사업을 현재 진행 중에 있다. 본 연구는 용역과업 내용에 포함되어 있지 않으면서 개선이 필요한 외항선(국전선.외국전선 포함) 선박입항보고서(최초.변경.최종)와 선박출항보고서(최초.변경.최종), 내항선입.출항신고서, 예선사용허가신청서 및 지정서, 도선사용허가신청서 및 지정서 등의 민원업무를, 사용자로 하여금 최소한의 노력으로 처리할 수 있도록 제출방법을 개선(EDI방식에서 온라인방식으로)하여 행정소요시간을 단축함으로써 PORT-MIS의 효율성을 높일 수 있는 방안을 제시하고자 한다. 이러한 노력을 통해 PORT-MIS EDI업무가 개선되어 선박입.출항보고를 1회롤 처리할 수 있다면 연간 29만9천건의 서류절감으로 약 1억3천7백만원의 물류비를 줄일 수 있으며, 시간 단축에 따른 간접비용을 계산하면 보다 많은 효과가 있다고 판단된다. 그리고 내항선입.출항신고서 및 예.도선업무를 EDI방식에서 온라인방식으로 전환함으로써 선사와 예선업체 및 도선사협회가 대화형식으로 업무처리가 이루어져 분쟁을 최소화 할 수 있다면, 전자문서 31만6천건/년 절감으로 1억3백만원/년의 예산이 절감될 것으로 예상된다.rr로 변화시켰고 inductive power는 200~800watt, bias voltage는 0~-200voltage로 변화시켰으며 식각마스크로는 SiO2를 patterning 하여 사용하였다. n-GaN, p-GaN 층 이외에 광소자 제조시 필수적인 InGaN 층을 100% Cl2로 식각한 경우에 InGaN의 식각속도가 GaN에 비해 매우 낮은 식각속도를 보였다. Cl2 gas에 소량의 CH4나 Ar gas를 첨가하는 경우와 공정압력을 감소시키는 경우 식각속도는 증가하였고, Cl2/10%Ar 플라즈마에서 공정 압력을 감소시키는 경우 식각속도는 증가하였고, Cl2/10%CHF3 와 Cl2/10%Ar 플라즈마에서 공정압력을 15mTorr로 감소시키는 경우 InGaN과 GaNrks의 선택적인 식각이 가능하였다. InGaN의 식각속도는 Cl2/Ar 플라즈마의 이온에 의한 Cl2/CHF3(CH4) 플라즈마에서의 CHx radical 형성에 의하여 증가하는 것으로 사료되어 진다.$ 이상을 나타내었다. 박막의 Sn/In atomic ratio는 0.12, O/In의 비율은 In2O3의 화학양론적 비율인 1.5보다 작은 1.3을 나타내었다.로 보인다.하면 수평축과 수직축의 분산 장벽의 비에 따라 cluster의 두께비가 달라지는 성장을 볼 수 있었고, 한 축 방향으로의 팔 넓이는 fcc(100) 표면의 경우 동일한 Ed+Ep값에 대응하는 팔 넓이와 거의 동일한 결과가 나타나는 것을 볼 수 있다. 따라서 이러한 비대칭적인 모양을 가지는 성장의 경우도 cluster 밀도, cluster 모양, cluster의 양 축 방향 길이 비, 양 축 방향의 평균 팔 넓이로부터 각 축 방향의 분산 장벽을 얻어낼 수 있을 것으로 보인다. 기대할 수 있는 여러

• Journal of the Korean GEO-environmental Society
• /
• v.25 no.8
• /
• pp.13-19
• /
• 2024

In this study, to reinforce the surface layer of weathered soil slopes where erosion and collapse of surface layer occur, compression strength tests were conducted by mixing carbon fiber and eco-friendly stabilizer (E.S.B.) To determine the optimal mixing ratio of E.S.B. and carbon fiber, E.S.B. was set at conditions of 10%, 20%, and 30%, and carbon fiber at 0.3%, 0.6%, 0.9%, and 1.2%. Additionally, to analyze the changes in compressive strength according to dry density and curing period, 85% and 95% of the maximum dry unit weight were applied, and curing periods were set to 3 days, 7 days, and 28 days. The standard strength for surface layer reinforcement of slopes is proposed as 4 MPa at 7 days and 6 MPa at 28 days according to ACI 230.1R-09 (2009). The compression test results showed that the unconfined compressive strength of E.S.B. reinforced soil met the standard strength at an E.S.B. mixing ratio of 10% or more for 95% compaction. Moreover, when carbon fiber was mixed with E.S.B. reinforced soil, a ductile fracture pattern was observed after the yield point due to compressive strength, indicating that the mixture could compensate for post-yield failure. It was analyzed that the maximum strength is exhibited at a carbon fiber mixing ratio of 0.6%. The unconfined compressive strength of carbon fiber reinforced soil increases by approximately 54-70% compared to the condition without carbon fiber.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.64 no.3
• /
• pp.225-233
• /
• 2019

This study was conduct to investigate the effect of mixed seed sowing and flour blending on the uniformity of flour quality of Korean domestic wheat. Two wheat varieties (Keumkang and Baegjoong) were selected for sowing mixed seeds, and their growth characteristics and flour quality were analyzed. Quality of flour blending with the same varieties was also evaluated. The ratios for mixed seed sowing and flour blending were from 0 to 100% with a 10% increase of interval for each treatment. On increasing the portion of Baegjoong in mixed seed sowing, the heading time was a little delayed, however, yield increased. The results of the flour quality showed lower damaged starch content and sodium carbonate SRC (solvent retention capacity) value for Keumkang than for Baegjoong. Protein quantity by protein content and quality by SDSS (Sodium Dodecyle Sulfate-Sedimentation) volume, lactic acid SRC, and mixograph pattern of Keumkang were superior to those of Baegjoong. Compared with mixed seed sowing, overall quality characteristics of flours with different ratios showed predictable and proportional change by flour blending. This demonstrated the successful application of flour blending, compared with mixed seed sowing, for improving the uniformity of flour quality.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.11 no.2
• /
• pp.233-247
• /
• 2016

Local food industry has been spreading all over the world. Korea is also actively applying and developing local food industry. However, relatively high distribution cost in Korean agricultural market is hindering its further growth. Distribution cost has close relation with shipping distance. Raised distribution cost brings major impacts not only on quality and price of products but also on greenhouse gas(carbon dioxide) emissions. Therefore, it is necessary to find a solution for inefficient distribution system of the local food industry to reduce overall cost and greenhouse gas. In this study, we present a location selection model for local food regional center using Analytic Hierarchy Process. The location of local food regional hub center is decided based on expert opinions on five factors: accessibility, quality, population, size of area, and shipping distance. The relative importance of the five factors has been concluded as follows: quality (0.430) ${\gg}$ population (0.262) ${\gg}$ travel distance (0.201) ${\gg}$ accessibility (0.075) ${\gg}$ and area (0.033). We apply and analyze the environmental management system model for Local food industry to develop the regional hub center site selection criteria and to analyze the effects of greenhouse gas emissions in the local food industry. This study, by applying and analyzing the environmental management system of the local food industry, is believed to be a valuable asset for managing greenhouse gas emission in the local food industry. Also, the data will be used for the autonomous local food industry's direct sales stall management. Eventually, this study will contribute so greatly to the local food industry's competitiveness that even large distribution companies will give way for the local food industry.

• Journal of Korean Society of Transportation
• /
• v.27 no.2
• /
• pp.95-105
• /
• 2009

Traffic accidents on highways are likely to happen when there is an imbalance in the complex relationships among key elements such as road geometries, driver related factors, and mechanical performances. The Demand-Effort Model (DEM), which evaluates highway safety, can be explained by the imbalance, which occurs when the level of demand of the driver's attention to the road environment exceeds that of the response from the driver. This study suggests a new model that improves the reliability of the current DEM through the reinterpretation on the physiological signals with the help of the Neural Network Model (NNM). The data were collected from 149 subjects, who drove a test vehicle on the Yongdong, Honam, and Seohaean Expressways in Korea. Three important results could be drawn from the recursive tests as follows; (1) Only 5 out of 10 parameters on the physiological signals which are currently used were proven to be meaningful through the Normality Test, Cluster Analysis, and Mann-Whitney Analysis. (2) The revised DEM, which internally uses the NNM, showed more reliable results than existing DEM. Group 1, which is based on the new DEM showed 80.0% of accuracy in measuring the level of driver's efforts, however, that of Group 2 based on the current DEM was 74.3%. (3) Field tests on the Honam Expressway showed lower 'type II error' with the new DEM (40.5%) than the old DEM (58.8%). The DEM is designed as a quick and easy way to determine highway safety prior to the minute road safety audit (RSA) by a professional audit team. Then a new DEM, which is based on the NNM, needs to be considered since it showed higher reliability and lower error.