• The Korean Journal of Applied Statistics
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• v.13 no.2
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• pp.457-476
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• 2000

In this study, we have proposed a sampling method and an estimation method for efficiently estimating the mean of a population which has a linear trend. These methods involve drawing a sample by the so-called "centered balanced systematic sampling", which is an extension of systematic sampling, and then estimating the population mean with an adjusted estimator, not with the sample mean itself. We used the concept of interpolation in determining the adjusted estimator.\Ve compared the efficiency of the proposed estimator with those of the estimators from existing methods, under the expected mean square error criterion based on the infinite superpopulation model introduced by Cochran(1946). The proposed method is for use in the case when the sample size n(2 5) is an odd number and k(the reciprocal of the sampling fraction) is an even number. A good result was also obtained in an example using computer simulation. simulation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5061-5065
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• 2013

Background: Oral tongue squamous cell carcinoma (OTSCC) is the most common cancer diagnosed within the oral cavity worldwide. Many studies in India report OTSCC ranking among the top two most common subsites within the oral cavity. India is often labeled the oral cancer capital of the world. The incidence of tongue cancers in the population-based cancer registry (PBCR) of Chennai is showing an increasing trend. A majority of the oral cavity cancers (85%) in our cancer center present in advanced stages (III and IV). In contrast, early tongue cancers (stages I and II) constitute nearly 45% of all OTSCCs. Aim: The aim of this study was to analyze the clinical profile and epidemiological trends in our early stage tongue cancer patients with an emphasis on tobacco and alcohol habits. Materials and Methods: This retrospective analysis was based on a prospectively collected database of 458 consecutive early stage OTSCC in-patients at a tertiary care oncology centre in Chennai between 1995 and 2008. Results: Our study suggests that the earlier trends have clearly changed whereby nearly half of our patients are now never-tobacco users. The findings of the study indicate that a majority of the patients were never alcohol users (86.4%) and nearly half of them were never tobacco users (49.3%), and they had the best survival outcomes. This increasing trend of OTSCC among non-tobacco users is in contrast to our earlier experience of tongue cancer more than five decades ago.The median age of patients in our study was 53.3 years; the male to female ratio was approximately 2:1. The median follow up for the 458 patients was 53 months. Conclusions: Our study importantly as well as interestingly shows a conspicuous absence of association with the traditional risk factors, tobacco and alcohol.

• Journal of Environmental Impact Assessment
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• v.23 no.5
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• pp.364-378
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• 2014

Ecological Footprint (EF) in Korea has increased steeply over the past 50 years and, thus, the overshoot. It has been known that the main causes of the overshoot are population growth and the increase of the consumption intensity per person. In this study, the EF trend in Korea is analyzed for the past 50 years and it is found the major cause of the rapid increase of EF in Korea is the increase of the consumption intensity per person. Among the sectors of the consumption, Carbon Footprint (CF) from the energy consumption and Grazing Land Footprint and Fishing Grounds Footprint from the protein consumption are the major players for the increase. It is also found that if current trend of the EF per person would be maintained until 2060, EF in Korea would be expected to increase also continuously, despite of the decrease of the population from 2031. Therefore, the direction of the environmental management should be considered for inducing the change of the individual consumption patterns and the behavioral changes.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.56.1-56.1
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• 2013

Supernovae type Ia (SNe Ia) cosmology is providing the only direct evidence for the presence of dark energy. This result is based on the assumption that the look-back time evolution of SNe Ia luminosity, after light-curve shape correction, would be negligible. However, the most recent compilation of SNe Ia data shows systematic difference in the Hubble residual (HR) between the E and Sd/Irr galaxies, indicating that the light-curve fitters used by the SNe Ia community cannot quite correct for a large portion of the population age effect. In order to investigate this possibility more directly, we have obtained low-resolution spectra for 30 nearby early-type host galaxies. This data set is used to estimate the luminosity-weighted mean ages and metallicities of host galaxies by employing the population synthesis models. We found an interesting trend between the host galaxy age and HR, in the sense that younger galaxies have positive residuals (i.e., light-curve corrected SNe Ia luminosity is fainter). This result is rather independent of the choice of the population synthesis models employed. Taken at face value, this age (evolution) effect can mimic a large fraction of the HR used in the discovery of the dark energy. This result is significant at 1.4 - 3 sigma levels, depending on the light curve fitters adopted, and further observations and analyses are certainly required to confirm the trend reported here.

• Nutrition Research and Practice
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• v.10 no.2
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• pp.188-197
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• 2016

BACKGROUND/OBJECTIVES: The purpose of this study is to analyze daily kimchi, vegetable and fruit consumption by general characteristics and vegetable and fruit consumption from 1998 to 2012 by the Korean population based on the data of the KNHANES (Korea National Health and Nutrition Examination Survey). SUBJECTS/METHODS: This study is based on the 1998-2012 KNHNES. Analysis data on 54,700 subjects aged 19 years and older were obtained from health behavior interviews and the 24-hour dietary recall method. RESULTS: Daily kimchi consumption and portion size of kimchi decreased significantly from 1998 to 2012 (adjusted P for trend < 0.0001). Meanwhile, daily consumption of both non-salted vegetable and fruit with and without kimchi did not significantly change between 1998 and 2012. Reduced consumption of kimchi, non-salted vegetable, and fruit was observed for both genders as well as daily meal episodes and cooking locations. Male and female subjects with insufficient non-salted vegetable and fruit intake were increased 1.4 times and 1.3 times, respectively, in 2012 than 1998. All subjects consumed at least 400 g/day of non-salted vegetable, fruit, and kimchi in each survey year, although they consumed insufficient amounts (< 400 g/day) of non-salted vegetable and fruit without kimchi. CONCLUSIONS: Since Koreans generally consume high amounts of fermented vegetables, including kimchi, total vegetables and fruit. Consumption of these foods by the Korean adult population reached 400 g, which is the recommended intake of the WCRF/AICR. Based on this result, it is necessary to promote consumption of kimchi in the Korean population and research the development of low sodium kimchi in the future.

• Journal of Korea Water Resources Association
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• v.42 no.10
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• pp.795-807
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• 2009

In this study, homogeneity analysis was performed between rainfall observation data set of Chukwooki (CWK) and rainfall observation data set of modern rain gage (MRG) using Bootstrap method. Since traditional statistical homogeneity test method are validated only when distribution of their population is known, meteorological data which their statistical distributions of population are complicated were difficult to verify the homogeneity and there were plenty of room for doubt for their statistical significance using historical method. In this reason, in this study homogeneity test was evaluated between two data sets using bootstrap method which is not necessary to infer distribution of population. The test results show that there was an statistical homogeneity between CWK and MRG except for slight impact of climatical trend.

• Convergence Security Journal
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• v.15 no.1
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• pp.11-18
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• 2015

Our country is a nation accomplished the economic growth and democracy at the same time on the bases of human capitals. However, the laborers as human capitals are aging as well due to the population aging. These aging phenomena are impacting on our country's economy, society, and through the culture. It seems to increase the proportion of the elderly in the labor market of private security caused by continuously increasing the number of elderly employees in long-term trend and their preferences for the security services. These changes of labor market trend may result various problems including relevant laws and systems, the changes of laborers' ability, increase of crimes and so on. To prevent such potential problems, firstly the limits of maximum working hours of elderly private guards have to be set up, and the rest times for them must be secured. Furthermore, the declines of elderly laborers' abilities have to be reduced through the systematic educations relevant to their jobs to cover the rapidly declining elderly laborers' physical abilities. Lastly, the increase of crimes should be reduced through the education contents to be able to arouse their attentions by extending the time of job training and informing of criminal cases.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5567-5577
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• 2013

The prevalence of oral cancers (OC) is high in Asian countries, especially in South and Southeast Asia. Asian distinct cultural practices such as betel-quid chewing, and varying patterns of tobacco and alcohol use are important risk factors that predispose to cancer of the oral cavity. The aim of this review is to provide an update on epidemiology of OC between 2000 and 2012. A literature search for this review was conducted on Medline for articles on OC from Asian countries. Some of the articles were also hand searched using Google. High incidence rates were reported from developing nations like India, Pakistan, Bangladesh, Taiwan and Sri Lanka. While an increasing trend has been observed in Pakistan, Taiwan and Thailand, a decreasing trend is seen in Philippines and Sri Lanka. The mean age of occurrence of cancer in different parts of oral cavity is usually between 51-55 years in most countries. The tongue is the leading site among oral cancers in India. The next most common sites in Asian countries include the buccal mucosa and gingiva. The 5 year survival rate has been low for OC, despite improvements in diagnosis and treatment. Tobacco chewing, smoking and alcohol are the main reasons for the increasing incidence rates. Low socioeconomic status and diet low in nutritional value lacking vegetables and fruits contribute towards the risk. In addition, viral infections, such as HPV and poor oral hygiene, are other important risk factors. Hence, it is important to control OC by screening for early diagnosis and controlling tobacco and alcohol use. It is also necessary to have cancer surveillance at the national-level to collect and utilise data for cancer prevention and control programs.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.1
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• pp.129-134
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• 2010

Low-carbon Green Growth is highlighted as the main political issue from in and outof Korea. Recently Korean government announced the vision for low-carbon green growth. Considering this as a starting point the carbon emission estimation has become an important factor in the city planning. In order to realize the carbon reduction planning, this research was focused on the trend analyzes between the carbon exhaust estimation as well as the land use change for the past 40 years in Jinju. The image processing data of past aerial photography and the land suitability assessment databases were used to collect the useful information's for the land trend analysis for 40 years. As the results, the land use changes by new residential developments have led to increase the carbon emissions and population concentration rapidly. The urban management planning for low carbon and green growth should consider carbon emissions by population growth derived from land use change. Further research need to estimate the accurate carbon exhaust using relationship model with fuel consumption, carbon estimation, and land use.

• Journal of the Korea Convergence Society
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• v.10 no.5
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• pp.51-61
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• 2019

The purpose of this study was to investigate the association between socioeconomic status and blood heavy metal concentration in Korean adult population using the Korea National Health and Nutritional Examination Survey(KNHANES 2013-2015). Multiple logistic regression analysis was used to determine the association between socioeconomic status and the blood heavy metal concentration. Positive association was found between education and income level and blood concentration of mercury while those of lead and cadmium were negatively associated education and income level in Korean adult population (P for trend <0.001). At the point of an increase in the prevalence of heavy metal concentrations in the blood, a national public health policy will be needed to address the inequity of health due to socioeconomic factors.