• Survey Research
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• v.11 no.1
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• pp.123-144
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• 2010

In new sample design for Korea Housing Survey to research about housing policy, total strata are forty five because individual results of sixteen regions are estimated. The sample size is determined by sample errors of several variables which are the living area, family income, householder income, and living expenses. The sample size of each region is determined by relative standard error of existing result, and the strata sample size is to use the square root proportion allocation. Enumeration districts are sampled by the probability proportion to size systematic sampling in proportion to the enumeration district size, and the systemic sampling to use assortment characteristics. We considered a new apartment complex because of variation reflections which are rebuilder and redevelopment of houses. To get estimators of mean and variance, we used the design weighting, non-response adjusting, and post-stratification. In order to consider estimation efficiency, we calculate the design effect using estimators of variance.

• The Korean Journal of Applied Statistics
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• v.10 no.2
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• pp.215-226
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• 1997

The purpose of the labor statistics survey is to collect materials on employment, wages and the working time and to analyze the trend of the labor situation. in this research, the stratification variables are industry and the size of establishment. The sample are selected by stratified one stage sampling method in order to produce the reliable estimates of labor statistics. For local labor statistics, we design the sample survey using the city and province as sub-population. So we are able to produce the local area estimates of labor statistics with respect to industry and the size of establishment.

• Journal of the Korean Data and Information Science Society
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• v.15 no.1
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• pp.1-10
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• 2004

In the Korean Economically Active Population Survey(EAPS), the sample sizes for small areas are typically too small to provide reliable estimators because the EAPS has been designed to produce unemployment statistics for large areas such as Metropolitan Cities and Province. In this study, we consider the synthetic and composite estimators for the unemployment rate of small areas, and apply them to real data on Choongbook province which is from the Korean EAPS of December 2000. The mean square errors of these estimators were estimated by the Jackknife method, and the efficiencies of small area estimators were evaluated in terms of the relative standard errors and the relative root mean square errors. As a result, the composite estimator is much more efficient than other estimators and it turns out that the composite estimator can produce the reliable estimates of the unemployment rate of small areas under the current EAPS system.

• Journal of Soil and Groundwater Environment
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• v.20 no.7
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• pp.53-60
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• 2015

This study suggested the new site classification system according to land use, type of contamination and contaminants. Because the present site classification system can not cover all the areas, we changed the concept of land use to more detail one and enlarged the concept of other areas to cover all the areas not defined as certain land use. In case of the present industrial area, it was merged as other areas to avoid the confusion with oil and toxic material storage tank farm area. Accident area was separated from other areas and defined as only accident area caused by the mobile storage facility. In addition to classify the sites according to the basic land use, we classify the sites again in lower level according to the type of contamination and contaminants. With this classification system, we proposed different soil sampling strategy with the consideration of the origin of contamination and the interactions between soil and contaminants. We removed the surface soil sample (0~15 cm depth) around above storage tank because it was not a effective sample to assess whether that area contaminated or not. We also proposed to take the deeper soil samples at minimum three sampling points to confirm the depth of contamination in exploratory soil survey. We also proposed to remove the one point of 15 m depth sampling because it is not effective to confirm contaminated soil depth and needs the exhausted labor and cost. Instead of doing this, we added the continuous sampling to uncontaminated subsoil. Soil sampling points and depth in detailed soil survey is determined based on the results of exploratory soil survey. Therefore, effectiveness and reinforcements of exploratory soil survey would play an important role in improving the reliability of detailed soil survey.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.523-534
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• 2010

This paper aims to develop a revitalized strategy for Daecheongdong district located on surrounding area of Daecheong dam, which general development projects are restricted by the acts of Green-belt area and Water supply protection zone. The study area consists of 13 villages in Donggu, Daejeon city. This study performed not only survey of amenity and human resources in the whole study area, but also development of new strategy integrating $1^{st}$, $2^{nd}$, and $3^{rd}$ industries for agriculture with potential. In the sample survey to 11% of village people, the new strategy was accepted positively with 88% of Understanding and 65% of Agreement in answer. The composition plans of farming association and total brand in the study area were agreed by 30% of residents with strong opinion. Representative groups of people living in Donggu, outside of the study area, have also positive opinion of 86% for Purchasing of agricultural products, 89% of Experience tourism, and 61% of Corporation for the study area, which the answering rate was 11% among 326 people. Finally, this study also investigated the corresponding Acts on performing of the new projects extracted in this study.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.4
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• pp.1-14
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• 2019

The 1st Forest Health Management survey was conducted to examine the health of the forests in Korea. However, in order to understand the health of the forests, which account for 63.7% of the total land area in South Korea, it is necessary to comprehensively spatialize the results of the survey beyond the sampling points. In this regard, out of the sample points of the 1st Forest Health Management survey in Gyeongbuk area, 78 spots were selected. For these spots, the species diversity index was selected from the survey sections, and the spatial interpolation method was applied. Inverse distance weighted (IDW), Ordinary Kriging and Ordinary Cokriging were applied as spatial interpolation methods. Ordinary Cokriging was performed by selecting vegetation indices which are highly correlated with species diversity index as a secondary variable. The vegetation indices - Normalized Differential Vegetation Index(NDVI), Leaf Area Index(LAI), Sample Ratio(SR) and Soil Adjusted Vegetation Index(SAVI) - were extracted from Landsat 8 OLI. Verification was performed by the spatial interpolation method with Mean Error(ME) and Root Mean Square Error(RMSE). As a result, Ordinary Cokriging using SR showed the most accurate result with ME value of 0.0000218 and RMSE value of 0.63983. Ordinary Cokriging using SR was proven to be more accurate than Ordinary Kriging, IDW, using one variable. This indicates that the spatial interpolation method using the vegetation indices is more suitable for spatialization of the biodiversity index sample points of 1st Forest Health Management survey.

• International Journal of Railway
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• v.5 no.4
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• pp.139-143
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• 2012

In Korea, almost 700 industrial parks are under operation. Generally, industrial parks consist of national industrial parks and local industrial parks which are managed by a central government and by local governments respectively. The developing countries such as Korea, China and Vietnam etc. have constructed many industrial parks, which result in the change of land use pattern and also affect future trip demands. Therefore, in estimating traffic demands, it is very important to consider the industrial park development. This study aims to improve the methodology in estimating a freight trip generation rate with the data based on a nationwide commodity freight survey. The result showed that it is desirable to apply freight trip generation rate by the industry sector in estimating freight trip generations and using the production area of firm as an indicator. Specially, the reliability of the rates through a survey could be made sure because a sample rate based on firms in industrial parks was over 25% and the response rate was over 67%. The sample rate and response rate are very superior as compared to surveys conducted in many other countries. Because industrial parks have significant effects on forecasting transportation demand in pre-feasibility studies of transport and logistics projects, it is expected that the accuracy of freight trip demands would be improved through the results of this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.7
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• pp.1005-1014
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• 2002

The purpose of this study was to examine the effects of retail area image and shopping mall image on consumer behaviors in the retail area and in the shopping ma]1. Data were obtained from a survey to a stratified sample selected at the exits of five different malls. A total of 740 questionnaires were distributed, and 661 responses were analyzed. Stepwise regression analysis revealed that two retail area image factors of variety of stores and atmosphere significantly affected all three consumer behaviors (shopping, service facility visits, social activities). Stepwise logistic regression showed that facility and atmosphere of the retail area image and product & service and convenience of the fashion shopping mall image affected seven consumer behaviors in the shopping mall. The results indicate that the retail area image as well as the shopping mall image affects a variety of consumer behaviors in the shopping mall though no shopping mal1 image affects behaviors in the retail area.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.19-23
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• 2001

This study was conducted to monitor the residue of the herbicide butachlor in major crops. The residue monitoring covered 106 samples of rice, barley, garlic, onion, and strawberry colledted from markets of intensive cultivation area including Kwangju, Daegu, and Pusan. The residue levels in 27 sample of polished rice produced by applying the herbicide were below the detection limits adopted analytical method. The residue levels in 21 sample of garlic, 18 sample of onion, and 18 sample of strawberry which were succeeding crops after paddy rice were also below the detection limits. In consequent, all the samples resulted safe status in terms of the butachlor residue level in agricultural produce.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.215-218
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• 2007

Recently, information-oriented whole domain and scientific management method for nation-wide territory is widly being used due to the remarkable development such as GIS and RS. In addition to this, request for analyzing forest spatial information has been increasing to manage forest resources efficiently. Although forest information using satellite image and GIS has been built to analyze a large amount of forest information scientifically, there are many difficulties to gather information because normally forest area is large and difficult to access.. This research uses high resolution satellite and digital aerial photograph around Kyungju city area to classify forest area, and stratifies forest area through a spot survey and a comparison of sample area. It will be possible for us to draw a more detailed map of forest area than 1/25000 map of forest area through these works.