• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3983-3991
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• 2013

Census transform is one of the stereo vision methods which is robust to radiometric distortion and illuminance change. This paper proposes a hybrid census transform using the mini census transform and the generalized census transform concurrently. This method uses simplicity of mini census transform and noise feature of generalized census transform together. This paper performed stereo matching containing post processing to evaluate each methods. The result shows that hybrid census transform has similar performance to generalized census transform and mean value of calculation complexity between mini census transform and generalized census transform.

• The Korean Journal of Applied Statistics
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• v.15 no.1
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• pp.45-55
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• 2002

The 2-level rotation design based on 3 rotation groups is discussed in view of Monthly Retail Trade Survey conducted by the Bureau of Census in U.S., and composite estimators for population characteristics are concerned. The generalized composite estimators and the recursive composite estimators are presented at 2-level rotation design with design gap and variance formulas for the composite estimators are provided. Also under the response variability related with covariance structure and correlation structure from repeated response, relative efficiencies of the composite estimators are compared.

• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.781-790
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• 1999

In this paper we consider estimation of cancer incidence rates for local areas. The raw estimates usually are based on small sample sizes and hence are usually unreliable. A hierarchical Bayes generalized linear model is used which connects the local areas thereby enabling one to 'borrow strength' Random effects with pairwise difference priors model the spatial structure in the data. The methods are applied to cancer incidence estimation for census tracts in a certain region of the state of New York.

• Journal of Korea Port Economic Association
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• v.34 no.4
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• pp.53-68
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• 2018

This paper analyzes comparatively business performance indicators and determinants of small and medium sized shipping logistics companies in Korea, using 2015 economic census data. For this purpose, this study estimates various business performance indicators according to 2015 small and medium sized companies classification standards, including operating income to sales and gross value-added to sales. In addition, this study analyzes determinants of business performance using generalized least squares models. The results indicate that average sales, operating income and value-added, sales and operating income per worker, operating income to sales, and material cost to sales of large sized companies are higher than those of small and medium sized companies. The business performance indicators differ by industry and size. Moreover, the determinants of business performance are analyzed in terms of the unemployment rate (-), number of employees (-), sales (+), labor cost ratio (+), and labor cost per employee (-) and the impacts of the individual explanatory variables based on elasticity are different. Finally, this quantitative information could be used to improve the business performance of domestic shipping logistics companies.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.411-417
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• 2021

This study aims to estimate the production function and total factor productivity (TFP) of Vietnamese seafood processing firms. At the same time, the study analyses the impact of internal factors of firms and the quality of economic institutions on the TFP of the Vietnamese seafood processing industry. The study uses the Function Control (FC) approach in TFP estimation and the Feasible Generalized Least Squares (FGLS) regression model in the analysis of factors affecting TFP. The study was carried out on the census data of enterprises of the Vietnamese seafood processing industry collected by the Vietnamese General Statistics Office and Provincial Competitiveness Index data of Vietnam Chamber of Commerce and Industry in the period from 2013 to 2018. Estimated results from the models show that: i) Vietnamese seafood processing firms are, currently, mainly labor-intensive, the TFP contribution and output is only about 2.258. ii) Factors such as the firm's age, firm's size, and the firm's ownership affect TFP. In which, firms that have few numbers of years of operation, small and medium firms, and private firms have low TFP. iii) Institutional quality and the provincial business environment have a positive impact on the TFP of Vietnamese seafood processing firms in this period.

• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.891-908
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• 2010

In Korea, the small area estimation method is currently unpopular in generating o cial statistics. Because it may be difficult to determine the reliability for small area estimation, although small area estimation ha a sufficiently good advantage to generate small area statistics for Korea. This paper inspects the method of making small area unemployment through the small area estimation method. To estimate small area unemployment we used an EBLUP-type estimator based on a logistic linear mixed model. To evaluate the EBLUP-type estimator we accomplished the real data analysis and simulation experiment from the population and housing census data. In addition, small area estimates are compared to large sample survey estimates. We found the provided method in this paper is highly recommendable to generate small area unemployment as the official statistics.

• Journal of Wetlands Research
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• v.23 no.2
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• pp.122-132
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• 2021

We reviewed the methods employed in Korean tidal flat surveys to measure the local abundance of the endangered wildlife and marine protected species, the fiddler crab, Austruca lactea. A complete census for infinite population is impossible even in a limited habitat within a tidal flat, and density estimates from samples strongly vary due to diverse biological and ecological factors. The habitat boundaries and areas shift with periodicities or rhythmic activities of organisms as well as measurement errors. Hence the local abundance calculated from density and habitat areas should be regarded as transient. This conjecture was valid based on the spatio-temporal variations of the density averages, standard error ranges, and spatial distribution of the crab, A. lactea observed for 3 years (2015-2017) in Songdo tidal flat in Incheon. We proposed the potential habitat areas using the occurrence probability of 50% from logistic regression model, reflecting the importance of habitat conservation value as an alternative to local abundance. The spatial shape of potential habitat predicted from a generalized model would remain constant over time unless the species' critical environmental conditions change rapidly. The species-specific model is expected to be used for the introduction of desired species in future habitat restoration/creation projects.