• 한국환경복원기술학회지
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• 제12권6호
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• pp.51-62
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• 2009

The purpose of this study is to analyze the profitability by selecting Pinus densiflora S. et Z. worthy of ornamental tree from among the cutting timber in the urban development project, and then presents the improvements. The study site is the whole area of Oedong-eup Gyeongju city Gyeongsangbuk-do and subject trees numbers are 2,180 trees. Analysis method is cost analysis because it is used generously pubic land development. In results, at first, in case of forest development currently cutting tree costs 7.3 million Won/ha. and no profit is occurred at all. Secondly, the forward direction order of tree treatments expenses are in sawdust production, selling lumber, selling ornamental tree, and selling ornamental tree, sawdust production, selling lumbered on the aspect of profits by the selling stumpage. Especially, selling trees as ornamental tree costs 127 million Won/ha. which shows the highest profits. Third, the management of ornamental tree pine tree after transplantation from development site costs 5 times less than purchasing the same quality trees. Hence, it is recommended to re-utilize the trees from the development sites to produce a high standard gardens and it also provides the basis for the low carbon green growth society.

• Membrane and Water Treatment
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• 제6권1호
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• pp.53-75
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• 2015

This paper provides an overview of the role of membranes in bioelectrochemical systems (BESs). Bioelectrochemical systems harvest clean energy from waste organic sources by employing indigenous exoelectrogenic bacteria. This energy is extracted in the form of bioelectricity or valuable biofuels such as ethanol, methane, hydrogen, and hydrogen peroxide. Various types of membranes were applied in these systems, the most common membrane being the cation exchange membrane. In this paper, we discuss three major bioelectrochemical technology research areas namely microbial fuel cells (MFCs), microbial electrolysis cells (MECs) and microbial desalination cells (MDCs). The operation principles of these BESs, role of membranes in these systems and various factors that affect their performance and economics are discussed in detail. Among the three technologies, the MFCs may be functional with or without membranes as separators while the MECs and MDCs require membrane separators. The preliminary economic analysis shows that the capital and operational costs for BESs will significantly decrease in the future due mainly to differences in membrane costs. Currently, MECs appear to be cost-competitive and energy-yielding technology followed by MFCs. Future research endeavors should focus on maximizing the process benefits while simultaneously minimizing the membrane costs related to fouling, maintenance and replacement.

• 한국산학기술학회논문지
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• 제14권3호
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• pp.1474-1480
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• 2013

본 연구는 TBM 공법의 구경별 자원기반 적산(원가 계산) 방식에 의한 공사비 적산을 수행하여 직접공사비와 총공사비를 분석하고, 이를 근거로 회귀분석을 수행하여 TBM 공법 구경별 직접공사비 및 총공사비를 추정할 수 있는 개산 공사비(개략 공사비) 예측 식 모델을 제시하였다. 본 연구에서 제시한 TBM 공법의 구경별 개산 공사비 예측 식 모델은 향후 TBM 공법 적용 현장의 사업기획, 예비조사, 타당성조사, 기본설계 단계에서 개산 공사비를 추정하는데 효과적으로 적용할 수 있을 것이다.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.952-959
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• 2022

Active construction work zones will result in longer travel time and/or longer travel distances for road users because of reduced speed limits and/or detours. This results in increased fuel consumption and increased emissions of harmful gases such as Carbon Monoxide (CO), Nitrogen Oxides (NOx), and Sulfur Oxides (SOx), which causes discomfort to the environment and road users around the work zone. The impact of such emissions should be considered while designing work zones or determining the number of days the roadway will be allowed to be closed partially or fully. This study develops a methodology to compute additional road user costs associated with such work zones. To achieve this goal, a) an extensive literature review is conducted, b) a framework to compute emission cost is developed, c) emission rates are computed for all counties (95) of the state of Tennessee, and d) a case study is conducted to demonstrate the use of the framework to estimate the additional impact of emission because of the work zone. For the case study conducted, the emission cost was computed to be $10,653.60 for the duration of the project. State DOTs can account for such road user costs while selecting contractors using A+B bidding. Accounting for such impact of emission will also indicate the agency's willingness to consider sustainability as a part of the business practices.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.616-623
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• 2013

One of the oldest, most common engineering problems is measuring the dimensions of different objects and the distances between locations. In AEC/FM, related uses vary from large-scale applications such as measuring distances between cities to small-scale applications such as measuring the depth of a crack or the width of a welded joint. Within the last few years, advances in applying new technologies have prompted the development of new measuring devices such as ultrasound and laser-based measurers. Because of wide varieties in type, associated costs, and levels of accuracy, the selection of an optimal measuring technology is challenging for construction engineers and facility managers. To tackle this issue, we present an overview of various measuring technologies adopted by experts in the area of AEC/FM. As the next step, to evaluate the performance of these technologies, we select one indoor and one outdoor case and measure several dimensions using six categories of technologies: tapes, total stations, laser measurers, ultrasound devices, laser scanners, and image-based technologies. Then we evaluate the results according to various metrics such as accuracy, ease of use, operation time, associated costs, compare these results, and recommend optimal technologies for specific applications. The results also revealed that in most applications, computer vision-based technologies outperform traditional devices in terms of ease of use, associated costs, and accuracy.

• 자원환경지질
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• 제45권4호
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• pp.447-454
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• 2012

• 에너지공학
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• 제8권2호
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• pp.317-324
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• 1999

This study suggests the effectiveness of an "extended" power system evaluation methodology based on LCA and energy input-output analysis techniques. This "extended" evaluation methodology is designed to incorporate total energy system costs through fuel cycle and external costs, including CO$_2$abatement cost. As an empirical test, we applied the methodology to orimulsion-fired power generation technology and found that orimulsion could be considered as in attractive base-load power generation fuel in terms of economic and environmental aspects, compared to conventional coal-fired power plant.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2000년도 학술발표논문집
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• pp.3-16
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• 2000

Protection agriculture is the essential choice for human to increase the efficiency of limited crop production area under harsh and changeable weather boundary conditions, extend growing season, maximize the crop yields, and then increase the sustainable income of the grower. The investment costs far greenhouses as well as labor and energy costs are much higher than for conventional plant production systems, so these can only be balanced by better crop yields, higher labor productivity, and higher energy efficiency. (omitted)

• Journal of Multimedia Information System
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• 제3권3호
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• pp.63-68
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• 2016

Environmental downtime produces a significant cost to organizations and makes them unable to do business because what happens in the data center affects everyone. In addition, the amount of electrical energy consumed by data centers increases with the amount of computing power installed. Installation of physical Information Technology and facilities related to environmental concerns, such as monitoring temperature, humidity, power, flood, smoke, air flow, and room entry, is the most proactive way to reduce the unnecessary costs of expensive hardware replacement or unplanned downtime and decrease energy consumed by servers. In this paper, we present remote system for monitoring datacenter implementing using open-source hardware platforms; Arduino, Raspberry Pi, and the Gobetwino. The sensed data displayed through Arduino are transferred using Gobetwino to the nearest host server such as temperature, humidity and distance every time an object hitting another object or a person coming in entrance. The raspberry Pi records the sensed data at the remote location. The objective of collecting temperature and humidity data allows monitoring of the server's health and getting alerts if things start to go wrong. When the temperature hits $50^{\circ}C$, the supervisor at remote headquarters would get a SMS, and then they would take appropriate actions to reduce electrical costs and preserve functionality of servers in data centers.

• 환경영향평가
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• 제11권2호
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• pp.93-107
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• 2002

The choice of big public investment project needs an appropriate feasibility analysis before it is implemented, bemuse a rot wisely chosen one would bring about big and longrun societal costs. But the feasibility analysis for the big public investment project in Korea has been done without linking the economic benefits and environmental damages. Consequently social conflicts arose frequently during and after project implementation, owing to such concerns asincreasing costs and serious ecological damages. The recent social conflict over the Saemangeum Project is a typical case. This reclamation project began in 1991 and finished 60% of the whole process in 1999, when its feasibility was again assessed under the public pressure by the joint assessment team consisting of both citizen's and government's professionals. Even the assessment report by this joint team could not show the convincing results owing to the improper assessment procedure and failure to set proper feasibility criteria. This paper pointed out the limitations of our current procedure of feasibility assessment and identified the concrete problems that atosee during the recent reassessment process of the Saemangeum reclamation project by the joint team. In order to improve the current problem-ridden practices, it is concluded by the policy recommendation for establishing a right feasibility assessment procedure for the public investment projects.