• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.3
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• pp.35-41
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• 1998

Cost estimate system Will be changed from the prime. cost calculation to the historical cost data because the present system has some problems. In this situation, each owner should prepare his own cost estimate system based on the historical cost data. In this study, the standard work items were classified and the criteria of their work amount computation were established for rural improvement projects. And also the historical cost data were collected in all range of rural improvement projects, and the database system, "HICOMS" (HIstorical COst data Management System) was built. In order to test the applicability of the HICOMS, standard work cost and contractor cost were compared. The results by HICOMS showed high significance and it was concluded that the HICOMS could be applicable for the cost estimate of the rural improvement projects. projects.

• Management Science and Financial Engineering
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• v.9 no.1
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• pp.4-10
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• 2003

We introduce a new estimator of the uncertainty of a jackknife estimate of standard error: the jack-knife-after-jackknife (JAJ). Using Monte Carlo simulation, we assess the accuracy of the JAJ in a variety of settings defined by statistic of interest, data distribution, and sample size. For comparison, we also assess the accuracy of the jackknife-after-bootstrap (JAB) estimate of the uncertainty of a bootstrap standard error. We conclude that the JAJ provides a useful new supplement to Tukey's jackknife, and the combination of jackknife and JAJ provides a useful alternative to the combination of bootstrap and JAB.

• Management Science and Financial Engineering
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• v.9 no.1
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• pp.1-10
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• 2003

We introduce a new estimator of the uncertainty of a jackknife estimate of standard error: the jack-knife-after-jackknife (JAJ). Using Monte Carlo simulation, we assess the accuracy of the JAJ in a variety of settings defined by statistic of interest, data distribution, and sample size. For comparison, we also assess the accuracy of the jackknife-after-bootstrap (JAB) estimate of the uncertainty of a bootstrap standard error. We conclude that the JAJ provides a useful new supplement to Tukey's jackknife, and the combination of jackknife and JAJ provides a useful alternative to the combination of bootstrap and JAB.

• Journal of the Korean Data and Information Science Society
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• v.20 no.5
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• pp.895-903
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• 2009

The penalized partial likelihood based on restricted maximum likelihood method has been widely used for the inference of frailty models. However, the standard-error estimate for frailty parameter estimator can be downwardly biased. In this paper we show that such underestimation can be corrected by using hierarchical likelihood. In particular, the hierarchical likelihood gives a statistically efficient procedure for various random-effect models including frailty models. The proposed method is illustrated via a numerical example and simulation study. The simulation results demonstrate that the corrected standard-error estimate largely improves such bias.

• The Korean Journal of Applied Statistics
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• v.25 no.4
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• pp.633-640
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• 2012

Biological methods are described for the assay of certain substances and preparations whose potency cannot be adequately assured by chemical or physical analysis. The principle applied through these assays is of a comparison with a standard preparation to determine how much of the examined substance produces the same biological effects as a given quantity (the Unit) of the standard preparation. In these dilution assays, to estimate the relative potencies of the unknown preparations to the standard preparations, it is necessary to compare dose-response relationships of standard and unknown preparations. The dose-response relationship in the dilution assay is non-linear and sigmoid when a wide range of doses is applied. The parallel line model (applied to the dose region with the steepest slope) is used to estimate the relative potency. In this paper, the statistical theory in the parallel line model is explained with an application to a dilution assay data. The parallel line method is implemented in a SAS program and is available at the author's homepage(http://cafe.daum.net/go.analysis).

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.6
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• pp.801-810
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• 2002

The purpose of this study is to suggest standard bodytype which offers criterion for the sizes and shapes to interpret various bodytypes, to estimate fitting, and to construct ready-made clothing. There were two ways of analyzing bodytypes of subjects from the viewpoint of statistic and beauty. We had carried on the analysis from the viewpoint of statistic in the Part(1) and we carried on the analysis from the viewpoint of beauty in this Part(2). Taken as a sample, the subjects were ninety-seven females who were between the aloes of 18 and 24 rears o1d. They were measured on November 1999. The data of seven hundred and four females,18∼24 year-old, from the National Somatometry Survey of 1997 were used for analysis, too. The first analysis from the viewpoint of beauty was executed to the front and side photographs of the subjects to analyze the general traits of the beautiful bodytype. The second analysis from the viewpoint of beauty was executed to subjects who were in both High-frequency proportion range and Beautiful bodytype group. As the result, four groups in Beautiful and High-frequency proportion range were selected. The standard proportion was analyzed with the size and shape of four groups. Based on the standard proportion, the size, shape and silhouette of the standard bodytype were analyzed. To verify the size, shape and silhouette of the standard bodytype, the location of the standard bodytype in the 1997 National Somatometry Survey group was analyzed. As the result, the standard bodytype was verified as proper criterion to interpret various bodytypes, to estimate fitting, and to construct ready-made clothing.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.679-682
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• 2004

Air void systems in hardened concrete has an important influence on concrete durability such as freeze-thaw resistance, water permeability, surface scaling resistance. Linear traverse method and point count method described at ASTM is the routine analysis of the air void system that have been widely used to estimate the spacing factor in hardened concrete. Recently, many concretes often have a spacing factor higher than the generally accepted $200-250{\mu}m$ limit for the usual range of air contents. This study is proposed to estimate the matrix spacing factor by calculation of simplicity. The matrix spacing factor needs two parameters that are air content and numbers of air voids in the hardened concrete. Those are obtained from the standard air-void system analysis of the ASTM C 457. The equation is valid for all values of paste-to-air ratio because the estimation of paste content is unnecessary at the using ASTM C 457. The matrix spacing factor yields a similar estimate of the standard spacing factor.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.232-233
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• 2019

The plater work in the standard of estimate presents a variety of construction types. However, there is a part that does not fit the change of specification standards and on-site construction status, and it was revised in 2019's standard of estimate. In this study, we analyzed in detail the factors affecting the changes in estimating standards in the plater work. There were changes in the specification standards previously presented as primary coat, secondary coat, and formal coat as well as changes in on-site construction status such as thickness according to the number of plastering. Therefore, it is analyzed that the estimating standards can be classified by the number of finishes according to the site conditions by reflecting the analysis of the specification standards and site application status, and suggesting the finishing standards according to the number of plastering.

• Animal Bioscience
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• v.35 no.8
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• pp.1151-1161
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• 2022

Objective: This study was conducted to estimate the association of age at first calving (AFC) with first lactation traits as well as lifetime performance traits in Murrah buffaloes. Methods: Data on first lactation and life time performance of Murrah buffaloes (n = 679), maintained at Indian Council of Agricultural Research-Central Institute for Research on Buffaloes, Hisar, India during the period 1983 through 2017, were deduced to calculate heritability estimates, genetic and phenotypic correlation of different first lactation and lifetime traits. The univariate animal model was fitted to estimate variance components and heritability separately for each trait, while bivariate animal models were set to estimate genetic and phenotypic correlations between traits under study. Results: The heritability was high for first peak milk yield (FPY, 0.64±0.08), moderate for AFC (0.48±0.07) and breeding efficiency (BE 0.39±0.09). High genetic correlations of first lactation total milk yield (FLTMY) with first lactation standard milk yield (FLSMY, 305 days or less), FPY, and first lactation length (FLL) was seen. Likewise, genetic correlation of AFC was positive with FLTMY, FLL, first dry period (FDP), first service period (FSP), first calving interval (FCI), herd life (HL) and productive days (PD). Significant phenotypic correlation of FLTMY was observed with HL, productive life (PL), PD, total lifetime milk yield (LTMY), standard lifetime milk yield (standard LTMY). Moreover, positive genetic and phenotypic correlation of FPY was observed with HL, PL, PD, total LTMY and standard LTMY. Conclusion: This study reports that AFC had positive genetic correlation with FDP, FSP, FCI, and unproductive days while, negative association of AFC was observed with FLSMY, PL, total LTMY, standard LTMY, and BE. This suggests that reduction of AFC would results in improvement of lifetime performance traits.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.6 no.9
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• pp.1-5
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• 1983

This study takes over the application of survey sampling theory to activity sampling and the application of activity sampling to time standard estimation. Cluster, stratified, and multistage sampling are studied in conjunction with random and systematic sampling. Estimation procedures that will maximize the information obtained per cost expended on the study and specification of the procedure to be used to estimate the accuracy of the estimates for the adopted procedure are considered. The use of multiple regression md linear programming to estimate standard element performance time from typical job lot production data is also considered.