• Journal of the Korean Statistical Society
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• v.32 no.4
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• pp.385-399
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• 2003

We first introduce the quasi-score estimating function and applied the quasi-score estimating function to nonlinear time series models. We proposed the M quasi-score estimating functions bounded functions for the quasi-score estimating functions. Also, we investigated the asymptotic properties of quasi-likelihood estimators and M quasi-likelihood estimators. Simulation results show that the M quasi-likelihood estimators work better than the least squares estimators under the heavy-tailed distributions

• International conference on construction engineering and project management
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• 2015.10a
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• pp.600-601
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• 2015

Both the importance and process of estimating Nuclear-power plant construction time and cost have increased in significance as energy user costs themselves have become more significant. In estimating construction time, few parameters are more significant than work item production rates and factors significantly affecting the rates. A standardized data collection tool was used to acquire a total of 401 data points from a S Nuclear-power plant project, for selected critical works: form-work, rebar-work, and concrete-pouring. With the data, several hypothesized drivers of the man-hour production rates and crew-day production rates were also analyzed. Findings from this study will enable industry professionals to enhance accuracy of time and cost estimation for nuclear power plant construction.

• Industrial Engineering and Management Systems
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• v.7 no.1
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• pp.9-22
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• 2008

As an extension of a previous work by the authors (Song and Esogbue, 2006), a new algorithm for automated modeling of nonstationary seasonal time series is presented in this paper. Issues relative to the methodology for building automatically seasonal time series models and periodic time series models are addressed. This is achieved by inspecting the trend, estimating the seasonality, determining the orders of the model, and estimating the parameters. As in our previous work, the major instruments used in the model identification process are correlograms of the modeling errors while the least square method is used for parameter estimation. We provide numerical illustrations of the performance of the new algorithms with respect to building both seasonal time series and periodic time series models. Additionally, we consider forecasting and exercise the models on some sample time series problems found in the literature as well as real life problems drawn from the retail industry. In each instance, the models are built automatically avoiding the necessity of any human intervention.

• Journal of the Korean Home Economics Association
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• v.40 no.8
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• pp.23-36
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• 2002

The purpose of this study is to analyze the actual condition of labor during the marriage by estimating the total labor-time of husband and wife and to prove the contribution of labor-time to household. The statistical life-time research data of Bureau of Statistics were used to prove the overwork of wives compared with husbands during the marriage. The result of the study can help to prove the wife's contribution of labor-time to household.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.169-171
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• 2012

Although work-efficiency of construction machinery is a critical factor for estimating its workable-quantity per unit time, the coefficient figure table presented in the Poom-Sam that is used for Construction Cost Estimation of public sectors in Korea is very subjective for practical usage. In order to suggest objective work-coefficient table for a Tub Grinder, domestic and overseas documentary records were investigated and on-going construction sites were also visited. The research found that the table can be revised by means of detailing down by several factors. The research will be the foundation for applying the rapid development of Construction Equipment and technology to the appropriate cost estimations and the ground work of related studies.

• Journal of the Society of Disaster Information
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• v.8 no.4
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• pp.328-335
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• 2012

The resource-based estimating based on standard unit price of construction work was estimated by multiplying the price per standard unit of work on the amount of labor, material, equipment use time. However, limitation of the resource-based estimating way does not adequately reflect the actual transactions prices. On the subject of water tunnel excavation as a new attempt to overcome these limitations, this study analyzed productivity by work type into cutter inspection/ exchange, TBM maintenance, TBM inspection/refueling, subsequent installations, tramcar, operating change, a cave-underground reinforcement / rock reinforcement, safety / meetings and analyzed actual cost estimating and the net advance rate based on this analysis result. Actual cost estimating calculation approach presented in this study can be utilized as a useful tool to predict the actual cost estimating in the TBM water tunnels field.

• Journal of the Korean Home Economics Association
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• v.28 no.2
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• pp.73-89
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• 1990

The aim of the present study is to estimates the economic value of household work done by fulltime home makers, using alternative methods of valuation household work in Pusan Korea. Eight findings, five different methods -Self Estimation by Home Makers, Reservation Wage, Opportunity Cost, Individual function Cost, Replacement Cost(Visiting Housekeeper, Housekeeper, General Managemet, Housekeeper & General Management)- are tried for the estimation of economic value of household work. The results of this study can be outlined as follows : 1) The economic value of household work varies substantially by the methods of estimating. The averages are : 2) The economic value of household work varies with the level of education, ages, the number of children, the stage of FLC in all method of estimation, and the level of income in self estimation by home makers, Reservation wage. Specially, FLC revealed good explanation variable in method of estimation as input household work time. 3) The gap between two-day survey and three-day survey in household work time questionaire didn't so much.

• Journal of Families and Better Life
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• v.14 no.3
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• pp.21-32
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• 1996

The purpose of this study is to suggest the solutions for policy related to estimating the household work to be set up. In this study the damages to housewife are compared in the viewpoints of the insurance company and the victim. And this study criticizes the unfairness in judging wife's contribution to matrimonial property in case of divorce. So for the future studies decisions to the concept of housewife the survey method for time-use data and the substitute wage are needed. And for setting up the policy continuous and objective discussion about the matter interest of the parties concerned and consensus of public opinion and the reform of image about the family nd household work are needed.

• Journal of the Korea Institute of Building Construction
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• v.4 no.4
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• pp.117-126
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• 2004

Construction industry is faced with the problems such as the quickly changeable circumstance and increasing construction companies due to regulation mollification of company registration. In order to overcome these problems, new estimation system based on historical estimation cost is ready to introduce by government step by step. But the time of transition for estimation system causes another problems such as chaos addition to simultaneity of a standard of estimation system and new estimation system, lack of related regulation, accumulation of historical extensive cost data, and adjustment methodology when historical estimation data is applied to next projects. The purpose of this study is to suggest the change factors by activities for estimating historical cost for apartment housing projects. New estimation system is based on historical construction data. For application of this system, the standard adjustment methodology system is necessary. and extensive cost data should be accumulated under an unified construction work classification system. Therefore in this study, according to the construction work classification system, every apartment housing project was classified to 16 work classifications, and 7 major composed items which occupy more than 85% of construction costs are analyzed by detailed activities and by average ratio and maximum ratio each of them. In the result of the study, furniture work, foundation work and masonry work are the works which have big gap of costs between average ration and maximum ratio. In addition to suggestion of change factor by work species, 5 qualified construction specialists are interviewed and change factors in 7 major works are analyzed.

• Journal of Software Assessment and Valuation
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• v.16 no.1
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• pp.21-26
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• 2020

The completeness appraisal of software is performed in various forms, such as assessing the completion level in the development process, calculating the defect rate, estimating the development cost, and calculating the redevelopment cost. Along with this, the problem that is often dealt with is estimation of the development time. Even in a dispute over completeness due to delays in software development, issues of calculating an appropriate development time required to develop a delivery software or a development time required for change requests are often included in the appraisal request. In this paper, we introduce the procedure and method for estimating the appropriate project time of software development so that the appraiser can be applied to the appraisal work for determining the completeness. The method is based on the manual for calculating the appropriate project period of software development project.