• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.201-205
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• 2010

Earthwork is an essential initial work discipline in construction projects and open to significant impacts of several factors such as weather, site conditions, soil conditions, underground installations and available construction machinery, calling for careful planning by managers. However, selection and combination of construction machinery and equipment for earthwork still depends on experience or intuition of managers in construction sites, with much room left for proper management in terms of cost, schedule and environmental load control. This research aims to analyze the performance of earthwork equipment and establish relations among various factors affecting a model for optimizing selection and combination of earthwork equipment as a precursor to the development of such model. We expect the conclusions herein to contribute to optimizing selection and combination of earthwork equipment and provide basic inputs for the development of applicable model that can save costs, reduce schedule and mitigate environmental load.

• Journal of information and communication convergence engineering
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• v.18 no.3
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• pp.167-175
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• 2020

The net income per unit area from crop production could be the most critical consideration for agricultural producers during cultivation planning. This paper proposes a scheme for predicting the net income per unit area based on machine learning and related calculations. This scheme predicts rice production and operation costs by applying climate and price index data. The rice price is also predicted by applying rice production and operation cost data. Finally, these predicted results are employed to calculate the predicted net income, which is compared with the actual net income. Consequently, the proposed scheme shows a meaningful degree of conformity, which indicates the potential of machine learning for predicting various aspects of agricultural production.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.127-129
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• 2002

This paper presents a fuzzy-GA method to resolve dispersed generator placement for distribution systems. The problem formulation considers an objective to reduce power loss costs of distribution systems and the constraints with the number or size of dispersed generators and the deviation of the bus voltage. The main idea of solving fuzzy nonlinear goal programming is to transform the original objective function and constraints into the equivalent multi-objectives functions with fuzzy sets to evaluate their imprecise nature and solve the problem using the proposed genetic algorithm, without any transformation for this nonlinear problem to a linear model or other methods. The method proposed is applied to the sample systems to demonstrate its effectiveness.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.369-374
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• 2003

Disassembly scheduling is the problem or determining the ordering and disassembly schedules or used or end-of-life products while satisfying the demand or their parts or components over a certain planning horizon. To represent and optimally solve the basic case. i e ., single product type without parts commonality, an Integer programming model is suggested for the objective or minimizing the sum or purchase, setup, inventory holding, and disassembly operation costs. Then, the basic model is offended to consider the cases or single and multiple product types with parts commonality. Computational experiments done on the examples obtained from the literature show that the integer programming approach suggested in this paper works well.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.311-316
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• 1995

Data on available feed resources, feeding practices and nutrient adequacy of rations under small farm conditions in Sri Lanka were obtained in a baseline survey involving 104 pig farms. The results showed that a wide range of non-conventional feedstuffs are used for pig feeding under typical small farm conditions and that dietary protein quality is a major factor limiting productivity. Following the survey, two on-farm trials were conducted to evaluate cheaper, alternative feeding strategies. In trial 1, a test diet was formulated using several non-conventional feedstuffs and compared with a commercial feed that is normally fed in the farms. In trial 2, the possibility of improving growth rates by amino acid supplementation was evaluated. The results demonstrated that feed costs can be considerably lowered through these packages. Some problems inherent to on-farm livestock trials are highlighted.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.63-66
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• 2002

Developers have, for some time now, recognised the benefits of acquiring "brownfields" sites for future urban development. The term “brownfield” generally refers to sites that have been previously occupied and in most cases this occupation has been for industrial usage. A key issue that developers face when considering the acquisition of a former industrial site is contamination and the costs associated with remediating the land to a level that renders the site suitable for its proposed use. Understanding all of the issues and implications associated with the remediation of contaminated land can be quite daunting. The process of remediation brings together a number of stakeholders that all have some influence on the outcome of the works. The stakeholders include the vendor, the purchaser, the regulatory authorities i.e. EPA and council, the Site Auditor and local residents. Careful planning and negotiation with the above stakeholders should be considered before committing to any remediation project.n project.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.90-96
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• 2013

During the cold forming, due to high working pressure acting on the die surface, failure mechanics must be considered before die design. One of the main reasons of die failure in industrial application of metal forming technologies is wear. Die wear affects the tolerances of formed parts, metal flow and costs of process etc. The only way to control these failures is to develop methods which allow prediction of die wear and which are suited to be used in the design state in order to optimize the process. In this paper, the wear experiments to obtain the wear coefficients and the upsetting processes was accomplished to observe the wear phenomenon during the cold forming process. The analysis of upsetting processes was accomplished by the rigid-plastic finite element method. The result from the deformation analysis was used to analyse the die wear during the processes and the predicted die wear profiles were compared with the measured die wear profiles.

• Management Science and Financial Engineering
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• v.11 no.1
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• pp.63-78
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• 2005

Disassembly scheduling is the problem of determining the ordering and disassembly schedules of used or end-of-life products while satisfying the demand of their parts or components over a certain planning horizon. This paper considers the case of the assembly product structure for the cost-based objective of minimizing the sum of purchase, setup, inventory holding, and disassembly operation costs. To represent and solve the problem optimally, this paper presents an integer programming model, which is a reversed form of the multi-level lot sizing formulation. Computational experiments on an example derived from the literature and a number of randomly generated test problems are done and the results are reported.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.65-76
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• 1990

A lot-sizing model for multi-stage MRP systems is proposed, in which known demands must be satisfied. In this model, an approach with considerations of initial inventory and limited production capacity is involved. Most of the studies on the lot-sizing techniques for multi-stage material requirement planning systems have been focused upon two basic approaches. One approach is to develope an algorithm yielding an optimal solution. Due to the computational complexity and sensitivity of the optimal solution to the problem of lot sizing, heuristic approaches are often employed. In this paper, the heuristic approach is used by sequential application of a single-stage algorithm with a set of modified cost by the concept of multi-echelon costs. The proposed method is compared with an lot-sizing method(Florian-Klein Model) to prove its effectiveness by numerical examples.

• Journal of Society of Preventive Korean Medicine
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• v.1 no.1
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• pp.42-47
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• 1997

Despite of increasing market share, oriental hospitals are now facing profit deterioration. In order to contribute to both better policy making of the Government Md corporate planning in the part of the individual hospitals this study attempted to identify the oriental hospital's financial characteristics. financial performance data for 1995, published by the Korea Institute of Health Services Management, were analysed from the structural perspective of patient composition, capital and resources input, medical revenue and costs, and financial efficiency and profitability. Some financial characteristics were drawn based on the results of the analysis. The areas that require corrective action and future study were also suggested.