• Advances in Computational Design
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• v.2 no.1
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• pp.1-13
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• 2017

This paper presents a variant of the Harmony Search Algorithm (HS) and its application to discrete optimization. The main proposed modifications regarding original HS are related to stopping criterion and reinitialization of population, called Harmony Memory. In order to investigate the efficiency of the algorithm, it was applied for obtaining optimal sections of reinforced concrete columns subjected to uniaxial flexural compression. To minimize the cost of the section, the amount and diameters of the reinforcement bars and the dimensions of the columns cross sections were considered as design variables. The obtained results were compared to those generated by other optimization methods. Since, to the examples, Harmony Search reached the same results achieved by Simulated Annealing, some additional analysis are presented in order to compare these methods regarding success rate and number of iterations to reach the optimum.

• Journal of Animal Environmental Science
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• v.4 no.1
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• pp.63-71
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• 1998

The dramatic increase in both swine and cattle production in Korea has presented problems related to protection of water resources. Animal wastes are a potentially valuable source of plant nutrients. Modern liquid waste management plans for a livestock housing need to focus on the slurry aeration and composting control methods and cost effective equipments. Recent developments in the animal manure liquid composting make it possible to improve the manure more easier to handle, reduce the odorous, labors and bedding materials, kill the weed seeds etc. However, there are some disadvantages, the aerator consumes much electrical power and initial cost is high. To solve these problems, this study is intended to develop a key points such as slurry aeration and dilution, liquid waste composting equipments.

• Journal of environmental and Sanitary engineering
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• v.16 no.2
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• pp.1-8
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• 2001

The water treatment by electrochemical method was performed to increase the yield of production. Continuous plug flow reactor was operated to treat poultry and domestic wastewaters. Experimental results were compared with experimental results of the wastewater treatment by chemical coagulation, they were increased over 10% in the removal efficiency of COD and the production rate of sludge was reduced by 30%. Ozone utilized to degrade or change the organic chemical structures, which removal efficiency increased to 20% in the electro-coagulation reactor. Economic evaluation was performed to estimate total cost of electro-coagulation reactor in comparison with that of chemical coagulation method. The total cost to treat 1000 ton/day of domestic wastewater was reduced by 50%.

• Health Policy and Management
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• v.13 no.2
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• pp.101-124
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• 2003

Performance of public hospitals is difficult to define and measure because not only their managerial or financial performance but also their role as a public entity is important. The purpose of this paper is to examine the internal and external factors that influence the performance of local government hospitals. A multiple regression was performed to analyze the effects of the environmental, organizational, operational, and cost-related factors on the return on total assets(ROA), operating margin(OM), and the ratio of Medicaid patients. Empirical results show that financial performance (ROA and OM) are more influenced by operational or cost-related factors, while the ratio of Medicaid patients is more affected by environmental or organizational characteristics. It is noteworthy that competition and the contract with private sector management have negative effects on the ratio of Medicaid patients that local government hospitals treat.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.5
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• pp.486-492
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• 2013

Energy cost has been increasing rapidly to comply with environmental regulations worldwide and the manufacturing industry who consumes more than half of the total energy needs to improve their cost competitiveness considering environmental costs. Machine tools are essential elements in manufacturing industry and efforts have been made recently to increase their energy efficiency mainly by German and Japanese machine tool builders. In this paper, trends in energy saving technology are described on the hardware and software sides of peripheral equipment of machine tools. In addition, the power consumption of a machining center is measured and analyzed to develop a software-based standby strategy for energy saving with peripheral equipment of machine tools.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.36-45
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• 2001

Natural disturbances and human development can cause habitat fragmentation. Plant and wildlife can become isolated, and habitat fragmentation and shrinkage have been recognized as a key issue facing the conservation of biological diversity. However, eco-corridors can alleviate the problem by providing linkages between isolated patches. The purpose of this study is to plan the eco-corridor for connecting urban forest via the urban stream with low cost and to restore the ecosystem. The results were as follows (1) Falco subbuteo, and Dryocopus martius inhabit in the study site. They are protected species designated by Korean Ministry of Environment. Thus the study site should be preserved as urban wildlife habitat species biodiversity (2) If the biodiversity of the study site is maintained properly, the eco-corridor can be constructed with low cost.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.83-90
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• 2004

Pulp mold is one of the famous environmental friendly materials, which made from re cycled materials such as old newsprints through the environmental friendly processes. Furthermore, the used pulp mold can be easily recycled and the pulp mold itself is biodegradable. However, the higher cost and some deficiency in physical properties of pulp mold have been considered as issues to be overcome for a substitute for polymeric packaging materials such as EPS (Expandable Polystyrene). The way for the optimization of a pulp mold mill was proposed in this report. The possible reduction of drying energy was calculated by using a computer simulation method, which could Provide the detailed information about mass balance of overall process. The simulated results showed a great possible curtailment of production cost by improving the forming systems, for example, increasing the temperature and the dryness of a wet pulp mold.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.6
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• pp.651-657
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• 2015

Recently, the need for asset management(AM) plan introduction to reduce increasing O&M cost with aging water facilities is on the rise. Therefore, asset inventory classification is necessary as the first step for AM plan construction. In this study, all assets of YW water treatment plant(WTP) were classified as 5 steps. In addition, specific code name was given to each asset which can increase compatibility in constructing the AM programs among WTPs. In the future, codes for attribute and status of asset will be allocated, which can facilitate proper AM operation.

• Journal of Agricultural Extension & Community Development
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• v.15 no.4
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• pp.577-597
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• 2008

The purpose of this study is to examine the effects of residents' perceptions of tourism impact and conflicts on residents' participation in rural tourism village. Method of analysis involves factor analysis and regression analysis in this study. In order to measure the level of perception, three factors(economic benefits, social benefits, social and environmental cost) are derived from the factor analysis. And also in order to measure the level of conflict, two factor(openness of information, leading of operation) are derive from the factor analysis. The result of regression analysis indicate that perceived economic benefits and social benefits are rather greater impacts on residents' participation than social and environmental cost, and also openness of information is rather greater impacts on residents' participation than leading of operation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.187-188
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• 2016

The purpose of this study is to develop a method of evaluating eco-efficiency of concrete based on environmental load emission, manufacturing cost, and durability in the concrete production process. Eco-efficiency is an advanced concept used to evaluate eco-friendliness of concrete. This technique intends to produce environment-friendly and highly durable concrete while minimizing environmental load on the ecosystem and manufacturing cost based on the results of service life assessment on concrete. This technique can be utilized to efficiently evaluate sustainability of concrete and find methods to improve it. Furthermore, the vision of this study is to contribute to implementation of environment-friendly concrete and construction industry.