• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.113-116
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• 2002

The rural population has been continuously decreased since the standards of living in rural communities is relatively lower than in urban. In other words, rural area has become less attractive for settlement. The concept of 'rural amenity' was introduced, to increase interests in the development of rural area. But, there has not been proper theories and methods to evaluate the amenity. In this study, rural amenity was classified and the elements of rural amenity was evaluated using statistical methods. The results of this study could be useful to assess the effects of the polices on improving rural amenities.

• Journal of the Korean Professional Engineers Association
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• v.42 no.4
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• pp.30-33
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• 2009

Great concerns on geotechnical risk & hazard assessment have increased due to human and economic damage by natural disasters with recent global climate changes. In this paper, geotechnical problems in particular, landslide which is interested in European countries and North America, were mainly discussed. For these, 18 key topics on geotechnical risk and hazards which had been discussed at the LARAM 2008 workshop in Italy were analyzed after grouping by subjects. Main topic contents consisted of applications such as field measurement, early warning systems, uncertainty analysis of parameters using radar, optical data and statistical theory and so on.

• The Korean Journal of Applied Statistics
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• v.7 no.1
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• pp.113-119
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• 1994

Logical and frequency probabilities are computed with discussion on their conceptual difference for the case of '14-faces dice' which was excavated in a Unified Silla period pond Anap-chi located at Kyung-ju City, Korea. This wooden dice has eight triangular and six square faces.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.277-278
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• 2006

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.93-96
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• 2001

Estimation of leaf wetness duration (LWD) facilitates assessment of the likelihood of outbreaks of many crop diseases. Models that estimate LWD may be more convenient and grower-friendly than measuring it with wetness sensors. Empirical models utilizing statistical procedures such as CART (Classification and Regression Tree; Gleason et al., 1994) have estimated LWD with accuracy comparable to that of electronic sensors.(omitted)

• Journal of the Korean Data and Information Science Society
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• v.18 no.3
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• pp.645-657
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• 2007

Several statistical procedures for assessment of bioequivalence of variabilities between two drug formulations in bioequivalence trials are reviewed and modified methods for assessing total variability are suggested. The problem of the current US FDA aggregate criterion for population bioequivalence and the necessity of disaggregate criterion are discussed with an illustrated example.

• The Korean Journal of Nuclear Medicine
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• v.35 no.3
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• pp.131-141
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• 2001

Purpose: We evaluated the sensitivity of the F-18 FDG PET by visual assessment and statistical parametric mapping (SPM) analysis for the localization of the epileptogenic zones in frontal lobe epilepsy. Materials and Methods: Twenty-four patients with frontal lobe epilepsy were examined. All patients exhibited improvements after surgical resection (Engel class I or II). Upon pathological examination, 18 patients revealed cortical dysplasia, 4 patients revealed tumor, and 2 patients revealed cortical scar. The hypometabolic lesions were found in F-18 FDG PET by visual assessment and SPM analysis. On SPM analysis, cutoff threshold was changed. Results: MRI showed structural lesions in 12 patients and normal results in the remaining 12. F-18 FDG PET correctly localized epileptogenic zones in 13 patients (54%) by visual assessment. Sensitivity of F-18 FDG PET in MR-negative patients (50%) was similar to that in MR-positive patients (67%). On SPM analysis, sensitivity decreased according to the decrease of p value. Using uncorrected p value of 0.05 as threshold, sensitivity of SPM analysis was 53%, which was not statistically different from that of visual assessment. Conclusion: F-18 FDG PET was sensitive in finding epileptogenic zones by revealing hypometabolic areas even in MR-negative patients with frontal lobe epilepsy as well as in MR-positive patients. SPM analysis showed comparable sensitivity to visual assessment and could be used as an aid in the diagnosis of epileptogenic zones in frontal lobe epilepsy.

• Tunnel and Underground Space
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• v.22 no.2
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• pp.86-92
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• 2012

Point estimate method has a less accuracy than Monte Carlo simulation that is usually considered as an exact probabilistic method, but this method still remains popular in probability-based reliability assessment in geotechnical and rock engineering, because it significantly reduce the number of sampling points and produces the statistical moments of a performance function in a reasonable accuracy. In the present study, we investigated the accuracy and applicability of point estimate methods proposed by Rosenblueth and Zhou & Nowak by comparing the results of these two methods with those of Monte Carlo simulations. The comparison was carried out for the problem of a lined circular tunnel in an elastic medium where an closed-form analytical solution is given. The comparison results showed that despite the non-linearity of the analytical solution, the statistical moments calculated by the point estimate methods and the Monte Carlo simulations agreed well with an average error of roughly 1-2%. This average error demonstrates the applicability of the two point estimate methods for the probabilistic reliability assessment of underground structures in combination with numerical analysis.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.241-251
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• 2014

This study was carried out to develop a simple, rapid and reliable assessment model to predict cold tolerance in Pittosporum tobira, a broad-leaved evergreen commonly used in the southern region of South Korea, which can minimize the possible experimental errors appeared in a electrolyte leakage test for cold tolerance assessment. The modeling procedure comprised of regrowth test and a electrolyte leakage test on the plants exposed to low temperature treatments. The lethal temperatures estimated from the methodological combinations of a electrolyte leakage test including tissue sampling, temperature treatment for potential electrical conductivity, and statistical analysis were compared to the results of the regrowth test. The highest temperature showing the survival rate lower than 50% obtained from the regrowth test was $-10^{\circ}C$ and the lethal was $-10^{\circ}C{\sim}-5^{\circ}C$. Based on the results of the regrowth test, several methodological combinations of electrolyte leakage tests were evaluated and the electrolyte leakage lethal temperatures estimated using leaf sample tissue and freeze-killing method were closest to the regrowth lethal temperature. Evaluating statistical analysis models, linear interpolation had a higher tendency to overestimate the cold tolerance than non-linear regression. Consequently, the optimal model for cold tolerance assessment of P. tobira is composed of evaluating electrolyte leakage from leaf sample tissue applying freeze-killing method for potential electrical conductivity and predicting lethal temperature through non-linear regression analysis.

• Journal of Environmental Health Sciences
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• v.46 no.2
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• pp.232-244
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• 2020

Objectives: The purpose of this study is to develop a management system for the safe handling of chemicals and related health management based on reporting under the Chemical Control Act (CCA). It is used to search handling information by constructing data linked to the name of companies, chemicals, products, etc. Methods: Due to the differences in submission periods for each reporting regulation of the Chemical Control Act, the data used is as follows: A statistical survey collected 26,222 companies in 2014 and 2016, Pollutant Release Transfer Registers (PRTR) collected 4,234 companies in 2015-2017, performance reports by handlers of hazardous chemical substances collected 14,658 companies in 2016-2018, and declarations for import of toxic chemicals collected 892 companies in 2016-2017. The total information on 36,080 companies is standardized based on company ID, name, business registration number, address, and more. The data were classified into information such as company, chemical, and product name and amounts handled and released, and then extracted according to criteria to establish relationships among classified information. Results: A search service was developed for handling information on chemical substances for reporting data by linking four reporting data: statistical survey, PRTR, performance report by handler of hazardous chemical substances, and declaration for import of toxic chemicals under the CCA. It was composed of five menus to search by regulation type, reporting regulation, companies and chemicals, and system management. Conclusion: It is necessary to use data linked by company, region, and chemical to respond and to prevent chemical accidents. In addition, these items can be utilized to perform handling and safety management of chemicals according to whether regulations under the CCA may be implemented.