• Communications for Statistical Applications and Methods
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• v.22 no.2
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• pp.137-146
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• 2015

Singh (2013) considered the dual problem to the calibration of design weights to obtain a new generalized linear regression estimator (GREG) for the finite population total. In this work, we have made an attempt to suggest a way to use the dual calibration of the design weights in case of multi-auxiliary variables; in other words, we have made an attempt to give an answer to the concern in Remark 2 of Singh (2013) work. The same idea is also used to generalize the GREG estimator proposed by Deville and S$\ddot{a}$rndal (1992). It is not an easy task to find the optimum values of the parameters appear in our approach; therefore, few suggestions are mentioned to select values for such parameters based on a random sample. Based on real data set and under simple random sampling without replacement design, our approach is compared with other approaches mentioned in this paper and for different sample sizes. Simulation results show that all estimators have negligible relative bias, and the multivariate case of Singh (2013) estimator is more efficient than other estimators.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.311-316
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• 2013

In order to maximize an efficient management of human cell resource under the cryogenic environments, in this paper, a middleware is introduced to support the function for multiple-perceiving RFID tags of intelligent sample case which can share medical information between sensor network devices. Optimized user interface is also designed for that. On based of the designing, special tasks required of a genetic resource working process can be processed on Complex Machine.

• Journal of Astronomy and Space Sciences
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• v.14 no.1
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• pp.1-17
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• 1997

The results of a restricted numerical simulation for the color gradients within globular clusters have been presented. The standard luminosity function of M3 and Salperter's initial mass functions were used to generate model clusters as a fundamental population. Color gradients with the sample clusters for both King and power law cusp models of surface brightness distributions are discussed in the case of using the standard luminosity function. The dependence of color gradients on several parameters for the simulations with Salpter's initial mass functions, such as slope of initial mass functions, cluster ages, metallicities, concentration parameters of King model, and slopes of power law, are also discussed. No significant radial color gradients are shown to the sample clusters which are regenerated by a random number generation technique with various parameters in both of King and power law cusp models of surface brightness distributions. Dynamical mass segregation and stellar evolution of horizontal branch stars and blue stragglers should be included for the general case of model simulations to show the observed radial color gradients within globular clusters.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.199-200
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• 2019

The purpose of the research is assessing the possibility of strength recovery for mortar added with accidently high amount of fly ash. For compressive strength at 28 day, the sample painted with sodium hydroxide showed higher compressive strength than the sample painted with calcium hydroxide. Regarding the curing conditions, the curing temperature 65℃ provided better conditions than the curing temperature 20℃ in aspect of solution penetration depth and reactivity of fly ash. In the case of drying after saturation, the case painted with sodium hydroxid 65℃ showed the clearest engrossing mark.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.239-244
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• 2011

This study analyzes the behaviors on stress, fatigue and vibration about bulldozer in operation. Maximum equivalent stress is shown with the frequency of 100 Hz in case of the harmonic vibration analysis applied with force. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to -105MPa and the amplitude stress of 0 to $1.617{\times}105MPa$, the possibility of maximum damage becomes 3.23%. This stress state can be shown with 5 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the design of bulldozer by investigating prevention and durability against its damage.

• East Asian Economic Review
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• v.22 no.2
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• pp.141-176
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• 2018

The paper analyzes and compares the effects of domestic monetary policy using DSGE, DSGE-VAR, and VAR based on a two-country open economy model of Korea and the U.S. According to impulse response analysis, a domestic interest rate hike raises won value in the case of DSGE and DSGE-VAR models, while in the case of the unrestricted VAR model, it lowers won value. In the marginal data density standard, DSGE-VAR (${\mu}=1$) is superior to DSGE or Bayesian VAR over the sample period. Conversely, in the in-sample RMSE criterion, especially for the won/dollar exchange rate, VARs are superior to DSGE or DSGE-VAR. It is necessary to study further if these differences are caused by model misspecification or omitted variable bias.

• Journal of Applied Reliability
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• v.18 no.2
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• pp.122-129
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• 2018

Purpose: This article develops an optimal reliability acceptance sampling plan for the case where the degradation quantity of the performance characteristic follows Weibull distribution. Method: For developing reliability acceptance sampling plans, the sample size and the acceptance constant are determined based on the accelerated characteristic of the test condition and the product. Results: The sample size and the acceptance constant are provided such that the constraints of the producer and the consumer risks are satisfied. Conclusion: Reliability acceptance sampling plans based on the accelerated degradation test method can be used for the quality control within a resonable amount of cost and time. In this article. an optimal reliability sampling plans are newly developed for this purpose.

• IE interfaces
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• v.17 no.1
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• pp.1-12
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• 2004

In a modern semiconductor device manufacturing industry, statistical bin limits on wafer level test bin data are used for minimizing value added to defective product as well as protecting end customers from potential quality and reliability excursion. Most wafer level test bin data show skewed distributions. By Monte Carlo simulation, this paper evaluates methods and sample size effect regarding determination of statistical bin limits. In the simulation, it is assumed that wafer level test bin data follow the Poisson distribution. Hence, typical shapes of the data distribution can be specified in terms of the distribution's parameter. This study examines three different methods; 1) percentile based methodology; 2) data transformation; and 3) Poisson model fitting. The mean square error is adopted as a performance measure for each simulation scenario. Then, a case study is presented. Results show that the percentile and transformation based methods give more stable statistical bin limits associated with the real dataset. However, with highly skewed distributions, the transformation based method should be used with caution in determining statistical bin limits. When the data are well fitted to a certain probability distribution, the model fitting approach can be used in the determination. As for the sample size effect, the mean square error seems to reduce exponentially according to the sample size.

• The Journal of Fisheries Business Administration
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• v.40 no.3
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• pp.147-167
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• 2009

The objective of this study is to analyze the determinants of at-home laver consumption expenditures using the data from a survey of households implemented in 2009. It happened that non-response ratios of monthly expenditures on dry laver and flavored laver among sampled households are 18.8% and 25.6%. Accordingly, this study tries to analyze the determinants affecting at-home laver consumption expenditures by using type II tobit model, one of sample selection models, to deal with sample selection bias caused from non-response data. Analysis results show the age variable positively affects expenditures on dry laver but negatively contributes to expenditures on flavored laver. In addition, the household size, the household's income, the degree of preference for laver have positive relationships with both expenditures. Household size elasticity and income elasticity of the expenditure on dry laver are estimated as 0.220 and 0.251. In the case of flavored laver, these elasticities are estimated as 0.484 and 0.261. Such analysis results can provide information on division of the at-home laver consumption market into groups with high willingness to expense and implementation of detailed marketing strategies to increase at-home laver consumption. The methodology of this study can be applied to consumer preference analysis on other marine products and other analyses on sample with non-response data in the fishery research.

• Korean Journal of Agricultural Science
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• v.42 no.1
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• pp.7-13
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• 2015

Ninety genes randomly selected from tobacco whitefly (Bemisia tabaci) cDNA library was studied for selecting target gene in order to control of tobacco whitefly using TRV-VIGS vector (tobacco rattle virus-virus induced gene silencing vector) with RNAi. First of all, the occurrence of B. tabaci adult according to agro-infiltration of TRV was no significant difference. And that of TRV inserted tobacco whitefly cDNA showed a significant difference in each sample. P CV and N CV sample were more than 80% could be confirmed in 5 samples, for example, wh11, wh36, wh46, wh50 and wh71. Lastly, the occurrence of nymph and egg also showed a significant difference in each sample. That could be confirmed in 11 samples, for example, wh01, wh09, wh10, wh15, wh16, wh23, wh24, wh48, wh64 and wh66. In case of wh46, wh50 and wh71 sample could be confirmed that occurrence of B. tabaci adult was many, but occurrence of B. tabaci nymph and egg was a little. So sample showed a physioecological good effect to control of whitefly need to be investigated variation of gene expression in whitefly body using qRT-PCR through individual test.