• Journal of the Korea Institute of Building Construction
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• v.11 no.1
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• pp.91-99
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• 2011

Bayesian network is a form of probabilistic graphical model. It incorporates human reasoning to deal with sparse data availability and to determine the probabilities of uncertain cases. In this research, bayesian network is adopted to model the problem of construction project cost. General information, time, cost, and material, the four main factors dominating the characteristic of construction costs, are incorporated into the model. This research presents verify a model that were conducted to illustrate the functionality and application of a decision support system for predicting the costs. The Markov Chain Monte Carlo (MCMC) method is applied to estimate parameter distributions. Furthermore, it is shown that not all the parameters are normally distributed. In addition, cost estimates based on the Gibbs output is performed. It can enhance the decision the decision-making process.

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.4
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• pp.93-113
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• 1997

In studying an EOQ-like inventory model for a manufacturing process, a number of findings were made. The system can "go out of control" resulting in a relatively minor problem state or "break-down". When the production system is in the minor problem statei produces a number of defective items. It is assumed that each defective piece requires rework cost and related operations. Once the machine breakdown takes place, the production system produces severely defective items that are completely unusable. Each completely unusuable item is immediately discarded and incurs handling cost, scrapped raw material cost and related operations. Two investment options in improving the production process are introduced : (1) reducing the probability of machine breakdown, breakdowns, and (2) simultaneously reducing the probability of machine breakdowns and setup costs. By assuming specific forms of investment cost function, the optimal investment policies are obtained explicitly. Finally, to better understand the model in this paper, the sensitivity of these solutions to changes in parameter values and numerical examples are provided.amples are provided.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.509-514
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• 2010

The purpose of this study is to analyze the technical efficiency and its determinants for Korean Apiculture farming by using from door to door and e-mail inquiry data. The analysis was implemented through the Cobb-Douglas stochastic frontier production function (SFPF) model including the technical inefficiency effect model for cross-sectional data. To measure the SFPF model, honey production was used for a dependent variable, and for input variables labor cost, preventive cost, material cost, feeding cost, depreciation cost were used. Farmer's age, farmer's career, farming scale, full-time or half-time firm and movement or fixed firm variables were used to measure the inefficiency effect model. The average technical efficiency on apiculture farming in Korea is estimated to be 0.8112. It means that there were technical inefficiency of about 18.88% in Korea apiculture farming. In this study there are some suggestions which could increase the technical efficiency of Korean apiculture farming.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.773-776
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• 2004

The so-called Life Cycle Cost (LCC) analysis on reinforced concrete bridge can provide useful information for initial design and maintenance plan of the RC bridge. This paper proposes an LCC prediction equation and a sensitivity analysis method for RC bridges. An LCC equation for the RC bridge which includes initial investment cost, maintenance cost, and demolition cost was derived and verified from the data for design and construction of an RC slab bridge. In order to solve uncertainty problem on actual discount rate and material characteristics in the analysis of LCC of concrete bridges, a sensitivity analysis method on the LCC using the Monte Carlo simulation technique was suggested.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.171-174
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• 2009

The standard estimation system, used to estimate the predetermined cost of construction work, is measured by the standard and typical construction methods and field conditions. And the standard estimation system is applied to basic data for the measuring of construction cost, such as the consumed quantity of material, labor hours, and machinery cost. However it does not reflect sufficiently for the diversity and reality of constructions work Therefore, this study is recognized the necessity of new cost estimation models for the rational construction cost estimation. To improve estimation technique and construction ability, it was analyzed labor hours, production volume based on the work crew in construction work.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.52-59
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• 2021

In this paper, we propose a system that allows small business owners focusing on the restaurant business to easily understand the management situation, and to manage the operation and management centering on the cost of food materials and profits and losses. In general, the metadata structure is different depending on the POS system, so it is necessary to first develop a standardized metadata model for a food material cost management system for small business owners in various industries. For that reason, the system proposed in this paper was applied to the cost management app by referring to the development of a data model using the metadata standard. In addition, in order to implement a cost profit/loss management system for small business owners in the restaurant industry, it was designed to support standardized metadata models from various types of POS systems, and is a hybrid app that can support a smart environment. Interface) was configured.

• Composites Research
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• v.19 no.1
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• pp.43-48
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• 2006

High performance fiber reinforced cement composites have better performances than traditional cement based materials, therefore, have been expected as new construction applications such as the materials for construction & bridge structure, repair and rehabilitation applications, anti-collapse applications, anti-noise applications etc. However, they have lots of the problems such as material design, fabrication method and structural analysis. Also, the most serious problems of High performance fiber reinforced cement composites have been expensive initial cost, lack of long-term exposure data. As a result, it is needed that the efforts for lowering the initial cost and accumulation of long-term exposure. There has been hardly assessment results of life cycle cost for HPFRCC in construction field, but some papers showed that total life cycle cost could be profitable if the initial cost could be reduced.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.16.2-16.2
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• 2009

Developing a low cost printing material that can replace silver for the formation of a conducting pattern is an important issue in printed electronics. We report a novel approach using a non-oxidized copper material during the printing and sintering process under ambient conditions, which was previously considered unachievable. An attempt was made to understand the conversion process of cuprous oxide nanoparticle aggregates on metallic copper crystals through chemical reduction in the solution phase. The detailed mechanism for this conversion, including the role of the surfactant and crystal growth, was examined.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.256-260
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• 2004

As a large portion of defence budget are alloted for military facility construction, reasonable budget estimation in the planning stage has been officers' main concerns. However the proper estimation of construction cost is difficult to be carried out due to the absence of systematic criteria. To improve the budget estimation for military facility construction, this study proposes a cost index model which can convert historical cost to current cost. Thus the developed cost index would enhance effectiveness of budget estimation process 3nd support reasonable decision making. This cost index model is developed by analyzing historical cost data with statistical methodology The study is executed by following process. First, factors which affect construction cost for the most are selected by analyzing historical cost data. second, the selected factors are categorized material cost, labor cost and equipment cost, and weights of those factors are calculated by dividing the cost of each factor by total item costs. Last, cost index is developed by using weighted average method.

• Journal of the Korean Geosynthetics Society
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• v.14 no.3
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• pp.13-20
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• 2015

Inappropriate backfill material and poor compaction cause the damage to sewer and ground settlement. To deal with such problem, flowable backfill material has attracted attention recently. A basic study was conducted in a bid to obtain optimum mixing ratio of backfill material with the characteristics of rapid hardening, pseudo-plasticity, flowability and anti washout ability and enhance the cost efficiency of backfill material. Through the test of optimal mixing ratio of rapid hardening, evaluation of optimal mixing ratio of backfill material was conducted. As a result, required performance as well as cost efficiency could be achieved by adjusting plasticizer even in case of increasing W/M of the paste of rapid hardening to 100%.