• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.115-122
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• 2010

The importance of the life cycle cost (LCC) analysis for bridges has been recognized over the last decade. However, it is difficult to predict LCC precisely since the costs occurring throughout the service life of the bridge depend on various parameters such as design, construction, maintenance, and environmental conditions. This paper presents a methodology for the optimal life cycle cost design of a bridge. Total LCC for the service life is calculated as the sum of initial cost, damage cost, maintenance cost, repair and rehabilitation cost, user cost, and disposal cost. The optimization method is applied to design of a bridge structure with minimal cost, in which the objective function is set to LCC and constraints are formulated on the basis of Korean Bridge Design Code. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on damage probabilities to consider the uncertainty of load and resistance. Repair and rehabilitation cost is determined using load carrying capacity curves and user cost includes traffic operation costs and time delay costs. The optimal life cycle cost design of a bridge is performed and the effects of parameters are investigated.

• Journal of the Korean Society of Radiology
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• v.8 no.3
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• pp.97-103
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• 2014

Decommission of medical cyclotron give rise to a lot of low-level radioactive waste and costs. Decommissioning cost should be reasonably calculated according to the decommissioning activities and installed components of facilities. In this paper, we investigated the experience on the cyclotron relocation from SNUH(Seoul National University Hospital) to SKKU(Sungkyunkwan University) and analyzed radioactive waste management costs by applying the disposal scenarios. Also considerations for decommissioning cost estimation are reviewed. The results could be utilized as a basic data for establishment on the methodology of decommissioning cost estimation and evaluation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.129-132
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• 2003

Used cutting fluid from machining processes is harmful to both environment and human health. Chemical substances that provide the lubrication function in the machining process are toxtc to the environment if the cutting fluid is released to soil and water and caused serious health problems to workers who are exposed to the cutting fluid in both liquid and mist form. Recently. cost of using cutting fluid is increasing as the number and the extensiveness of environmental protection laws and regulations increase. Therefore, the use of cutting fluid in machining processes place an enormous burden on manufacturing companies to cover the additional costs associated with their use and protection of our environment. Current trends in manufacturing are focused on minimizing or eliminating the use of metalworking fluids in machining processes. And the increased costs for the disposal of waste products (swarf, coolants and lubricants), especially in industrially developed countries, has generated interest in dry machining. A variety of new techniques are testimony that new technology has rationalized further efforts to research and implement dry machining processes. This paper presents the developed equipment, the process optimization and the applications in the field of surface grinding for the new cryogenic dry machining using a compressed cooling air. The investigated new machining process method shows many advantages compared to conventional techniques with cutting fluid.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.1-18
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• 2013

Animal and crop production systems were integrated on a single farm. This integrated farming system recycled nutrients on the farm. The separation of animal and crop production with the introduction of cheap commercial fertilizers, farms were not used land-applied manure. The on-line manure matching is one of the emerging business in the achievement of recycling and resource recovery. The manure matching actively promotes the reuse and recycling of by-products and manure. This study constructs to manure matching information system to solve the exchange problems between herders and croppers. Manure matching web sites designed. This paper introduces a web-based animal manure matching system. A manure matching service, part of the manure transport, links farmers who produce excess manure with farmers who can use the manure. Farmers registered with the service have requested manure. The manure matching service supports the transport project by linking farmers with excess manure with those farmers who can utilize the manure safely as a nutrient source. The goal of the service is to protect water quality by fostering efficient land application. Benefits to those who use the manure network include reduced disposal costs, lower purchase costs and recycling of manure. The manure matching is based on the principle that 'one persons waste is another person's fertilizer.' It provides a free online matchmaking service for environmentally safe manure recycling management system.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.841-854
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• 2014

This study aimed to analyze the selection criteria and priority settings for solid culture medium used in hydroponic crop production in farm households. Expert brain storming was carried out to extract solid culture medium selection criteria for hydroponic farming. As a result, 3 criteria of economy (cost), productivity, and environment, and 9 factors were extracted. A questionnaire survey of hydroponic farm households was conducted in Gyeonggi, Gangwon, and Chooncheong provinces. AHP analysis of the hydroponic solid culture medium selection criteria identified productivity as the most important criterion, chosen by 58.7% of the respondents, followed by economy (28.4%) and environment (12.9%). The 9 factors were rated by the respondents in the following decreasing order of importance: 1, crop yield (28.3%); 2, pest occurrence (18.5%); 3, maintenance/management costs (12.0%); 4, convenience of maintenance/management (13.4%); 5, initial investment cost (11.6%); 6, material energy consumption (6.5%); 7, waste recyclability (4.0%); 8, waste disposal costs (3.4%); and 9 environmental emissions (1.81%). These results imply that hydroponic farm households consider cultivation-related quality factors more important than economic factors, such as price of culture medium or installation cost.

• Journal of the Korea Institute of Building Construction
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• v.18 no.5
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• pp.499-506
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• 2018

The number of demolition work is rapidly increasing because the middle- and high-rised buildings constructed over the rapid industrialization and urbanization have been deteriorated in social and structural aspects. However, theoretical approaches or studies related to the demolition cost prediction are still insufficient. Thus, this study derived and analyzed important factors affecting the fluctuation of the building demolition costs. 14 factors was derived through literature reviews and experts' interview, and the importance of each factor was analyzed to the each work(temporary work, structure demolition, and waste disposal) and the entire demolition work by using descriptive analysis. The survey results showed that the demolition costs was greatly influenced by environmental properties of the site. The results of this study can be used as a basis for estimating the approximate cost of the demolition work.

• Health Policy and Management
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• v.22 no.1
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• pp.145-162
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• 2012

The purpose of this study is to understand magnitude and its related factors of user's cost-sharing for non-covered services in long-term care facilities. We corrected data for 1,016 subjects, based on the long-term care benefits cost specification. Eighteen subjects were excluded from the data analysis due to missing data on family care-givers characteristics. Finally, 998 subjects were included in the study. The average cost of non-covered services per month was 209,093 won and distributed from 0 to 1,011,490 won. There was a significant difference by the characteristics of family care-givers and long-term care facilities. The monthly average cost for meal materials per person was 199,181 won(0~558,000), average cost of additional charge caused by using private bed was 232,992 won (50,000~600,000), and costs for haircut and cosmetics were 8,599 won. For the rest, there were various programs costs(93,328 won), diaper and its disposal cost(109,628 won), purchase cost for daily necessaries(24,435 won) and etc. The related factors for the magnitude of non-covered services expenditures were education level of family care-givers, occupancy rate and location of LTC facilities, and the costs of using private bed, haircut and cosmetics, and various programs among non-covered services. These findings suggest that present level range of LTC facilities users' cost-sharing is wide and it is urgent to prepare the standard guideline for cost and level in non-covered services.

• Clean Technology
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• v.2 no.2
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• pp.51-59
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• 1996

Billions of tons of industrial waste are generated annually in industrialized countries. Managing and legally disposing of these wastes costs tens to hundreds of billions of dollars each year, and these costs have been increasing rapidly. The escalation is likely to continue as emission standards become even more stringent around the world. In the face of these rapidly rising costs and rapidly increasing performance standards, traditional end-of-pipe approaches to waste management have become less attractive. The most economical waste management alternatives in many cases have become recycling of the waste or the redesign of chemical processes and products so that wastes are prevented or put to productive use. These strategies of recycling or reducing waste at the source have collectively come to be known as pollution prevention. The engineering challenges associated with pollution prevention are substantial. This presentation will categorize the challenges in three levels. At the most macroscopic level, the flow of materials in our industrial economy, from natural resource extraction to consumer product disposal, can be redesigned. Currently, most of our raw materials are virgin natural resources that are used once, then discarded. Studies in what has come to be called industrial ecology examine the material efficiency of large-scale industrial systems and attempt to improve that efficiency. A second level of engineering challenges is found at the scale of individual industrial facilities, where chemical processes and products can be redesigned so that waste is reduced. Finally, on a molecular level, chemical synthesis pathways, combustion reaction pathways, and other material fabrication procedures can be redesigned to reduce emissions of pollution and unwanted by-products. All of these design activities, shown in Figure 1, have the potential to prevent pollution. All involve the tools of engineering, and in particular, chemical engineering.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.394-399
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• 2009

Since some decades ago, there has been a concern for resource depletion and environmental pollution associated with building properties. In addressing such impact of the built environment, there is a recognition of the existence of alternative building materials, fuels for energy supply as well as technologies for waste handling and disposal. Nevertheless, for long time, the choice between such alternatives was dictated by factors such as differences in prices and aesthetic values. A new important dimension in discriminating between different options is the environmental dimension. This aspect is important since buildings are one of the spatially big new additions to the natural environment that consume a lot of materials and energy during their long lifetime. Thus, with the environmental dimension kept in mind, a existing cost estimation needs to be changed. A new cost assessment method, Life Cycle Cost, should calculate overall costs with dimensional factors: investment and utility costs as well as maintenance costs over the lifetime of the building. Aiming to give an overview of the present status of Building Life Cycle Assessment(LCA) tools as a basis for further research and development including economic performance, this paper describes and compares 3 different tools for Life Cycle Assessment(LCA) and economic analysis of the green buildings. This paper compared these approaches based on various aspects. These include economic analysis method, evaluation duration, data of results(index). Use of the comparison analysis is to produce a better picture and indicate profits and shortcomings for the tools as a group; thus providing important direction improvement of LCA tool as well as further research and development of this group of tools.

• Nuclear Engineering and Technology
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• v.37 no.1
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• pp.91-100
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• 2005

Kyung-hee Thorium Fuel (KTF), a heterogeneous thorium-based seed and blanket design concept for pressurized light water reactors, is being studied as an alternative to enhance proliferation resistance and fuel cycle economics of PWRs. The proliferation resistance characteristics of the KTF assembly design were evaluated through parametric studies using neutronic performance indices such as Bare Critical Mass (BCM), Spontaneous Neutron Source rate (SNS), Thermal Generation rate (TG), and Radio-Toxicity. Also, Fissile Economic Index (FEI), a new index for gauging fuel cycle economy, was suggested and applied to optimize the KTF design. A core loaded with optimized KTF assemblies with a seed-to-blanket ratio of 1: 1 was tested at the Korea Next Generation Reactor (KNGR), ARP-1400. Core design characteristics for cycle length, power distribution, and power peaking were evaluated by HELIOS and MASTER code systems for nine reload cycles. The core calculation results show that the KTF assembly design has nearly the same neutronic performance as those of a conventional $UO_2$ fuel assembly. However, the power peaking factor is relatively higher than that of conventional PWRs as the maximum Fq is 2.69 at the M$9^{th}$ equilibrium cycle while the design limit is 2.58. In order to assess the economic potential of a heterogeneous thorium fuel core, the front-end fuel cycle costs as well as the spent fuel disposal costs were compared with those of a reference PWR fueled with $UO_2$. In the case of comprising back-end fuel cycle cost, the fuel cycle cost of APR-1400 with a KTF assembly is 4.99 mills/KWe-yr, which is lower than that (5.23 mills/KWe-yr) of a conventional PWR. Proliferation resistance potential, BCM, SNS, and TG of a heterogeneous thorium-fueled core are much higher than those of the $UO_2$ core. The once-through fuel cycle application of heterogeneous thorium fuel assemblies demonstrated good competitiveness relative to $UO_2$ in terms of economics.