Membrane filtration process is an advanced water treatment technology that has excellently removes turbidity and microorganisms. However, it is known that it has problems such as low economic efficiency and the operating stability. Therefore, this study was to evaluate on the economical feasibility and operational stability comparison of membrane and sand filtration process in Im-sil drinking water treatment plant. For the economic analysis of each process, the electricity cost and chemical consumption were compared. In the case of electric power consumption, electricity cost is 68.67KRW/㎥ for sand filtration and 79.98KRW/㎥ for membrane filtration, respectively. Therefore, membrane filtration process was about 16% higher than sand filtration process of electricity cost. While, the coagulant usage in the membrane filtration process was 43% lower than the sand filtration process. Thus, comparing the operation costs of the two processes, there is no significant difference in the operating cost of the membrane filtration process and the sand filtration process as 85.94KRW/m3 and 79.71KRW/m3 respectively (the sum of electricity and chemical cost). As a result of operating the membrane filtration process for 3 years including the winter season and the high turbidity period, the filtrated water turbidity was stable to less than 0.025 NTU irrespective of changes in the turbidity of raw water. And the CIP(Clean In Place) cycle turned out to be more than 1 year. Based on the results of this study, the membrane filtration process showed high performance of water quality, and it was also determined to have the economics and operation stability.

본 연구는 파라과이에 대한 조림투자의 경제적 타당성을 분석하기 위하여 수행되었다. 한국은 목재자 급률이 낮아 90년대 초반부터 적극적인 해외조림투자에 나서고 있으나, 그 투자의 대부분이 동남아시아 에 집중되어 있다. 이러한 상황에서 조림목 생장이 우수하고 적극적인 조림 지원 정책을 추진하고 있는 파라과이는 한국의 해외조림투자 대상지로서 훌륭한 대안이 될 수 있다. 하지만 지구 반대편이라는 지 정학적 위치에 대한 거리감으로 인하여 한국기업은 파라과이 해외조림투자에 대하여 적극적으로 검토하 지 않고 있다. 파라과이 조림투자에 대한 정보가 부족한 것도 기업의 접근을 막는 하나의 요인이며, 우 선적으로 조림사업의 수익성에 대한 자료가 요구된다. 본 연구에서는 파라과이 해외조림투자를 파라과 이 내수 시장에서의 원목 판매와 현지 위탁가공 후 한국시장으로의 제재목 수출, 두 가지 경우에 대하 여 경제적 타당성을 분석하였다. 그 결과, 두 시나리오 모두 높은 경제적 타당성을 가지고 있는 것으로 분석되었다. 원목의 내수시장 판매의 경우, IRR 9.64%, NPV U$ 2,811,888로 나타났다. 제재목 한국 수출의 경우, IRR은 17.51%로 현지원목판매 대비 7.87%p 상승하였고, NPV는 U$ 38,260,086로 현지 원목판매 대비 U$ 35,448,198 상승하였다. 본 연구는 원거리라는 점으로 인해 외면 받아온 남미, 특히 파라과이 조림 진출에 대한 가능성을 새롭게 분석한 것에 큰 의의가 있다하겠다.

We are now currently facing serious climate changes such as super typhoon, flood, intense heat, severe cold, super hurricane, drought, desertification, destruction of ecosystem, marine pollution, reduction of food production, destruction of tropical forests, exhaustion of water resources, climate refugees, etc. All of the above mainly derive from greenhouse gas exhaustion. Such harmful consequence might directly affect mankind’s sustainable development. If we keep using resources that emits greenhouse gases, the global temperature will rise about 3.2℃ by year 2050. In case of 3℃ rise in temperature, it will result in abnormal climate which will bring about severe property damage. Moreover, 20~50% of the ecosystem will become extinct. As Korea’s economy increasingly expands, so do our energy consumption rises. And because of the consequences that can be driven by increasing rate of resource use, not just Korea itself, but also the whole world should seriously concern about greenhouse gases. Although agricultural division only takes up about 3.2% of total greenhouse gas emission, the ministry of Agriculture, Food and Rural Affairs are taking voluntary actions to gradually reduce CO2 and so does each and every related organizations. In order to reduce CO2, introduction of new and renewable energy in farm house warming is crucial. In other words, implementing wood-pellet boiler and geothermal heat boiler can largly reduce CO2 emission compared to diesel boiler. More importantly, not only wood-pellet and geothermal heat is pollution-free but they also have economic advantages somewhat. In this thesis, the economic advantage and sustainablity will be introduced and proved through comparing practical analysis of surveyed farm house under structure employing wood-pellet boiler and geothermal heat boiler with Agriculture-Economic Statistic of 2012 who uses diesel boiler.

In light of the growing traffic congestion problem and congestion cost, the container transport by railway has to be increased. The freight transport by railway can have decided advantages over trucks in terms of energy efficiency, emissions and cost for certain freight movements, just as transportation in the metropolitan region can have great advantages over driving truck. But the freight transport by truck should gain significant mobility benefits from a freight railway system. Thus, the DMT(Dual Mode Trailer) transport system which is coupled railway transport advantages with load transport advantages has been developed and used in the european countries. The DMT transport will therefore serve the areas required by transport organizers. The purpose of this paper is to estimate economical feasibility analysis for development of DMT transport system. Consequently, this study analyzed the characteristics of the DMT system. The horizontal load.unload system is being considered as an adoptable DMT system in consideration of the situation in Korea.