• Journal of Environmental Science International
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• v.5 no.3
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• pp.337-346
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• 1996

The purpose of this study was to provide basic data of the growth characteristics of the landscape trees for better landscape planting design, construction and maintenance through the prediction of landscape change as time passes fly the analysis of survival rate, distribution patterns & increment percent of tree height, width, stem diameter (breast or surface) of widely used six tree species in Seongnam-si Eunhang-jugong apartment housing areas (8 years have passed after landsape alanting work). The main results can be summarized as followed. The tree survival rate of Pinus parviflora was the highest rate 89.2% than any other species, but Acer buergerianum showed the lowest survival rate at that of it 35.0%, & that of Picea abies 70.5 %, Metasequoia glyptostroboides 71.6%, Maknolia denudata 38.9%, Acer paimatum was 71.7%, As a whole, the tree survival rate of coniferous trees were relatively high. The tree height increment percent of the deciduous species wert relatively high. And that of Metasequoia glyptostroboides was the highest rate 11.61% than any other species, but that of Magnolia denudata was the lowest rate 5.59% than any other species. According to this results, the increment percent of trees in this apartment areas were comparatively lower than that of each related species planted in nursery area. And this results would be considered when landscape experts do landscape planting design, construction & maintenance. The distribution patterns of present tree size showed a Normal Distribution like any other biological features.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.1
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• pp.94-106
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• 2024

In this study, we conducted a survival analysis on battalion-level commanders(leaders), focusing on infantry battalion defensive operations using the big data of brigade-level KCTC(Korea Combat Training Center) training results. Unlike previous studies, we utilized the brigade-level KCTC training results data for the first time to conduct a survival analysis, and the research subjects were battalion-level commanders(leaders), which can affect the battle. At this time, the battle results were defined, and through cluster analysis, infantry battalions were divided into excellent, average, and insufficient units, and the difference in the survival rate of the commanders was analyzed through the Kaplan-Meier survival analysis. This provided an opportunity to objectively compare the differences between excellent and insufficient units. Subsequently, factors affecting the survival of commanders were derived using the Cox proportional hazard model, and it was possible to confirm the influencing factors from various angles by also using the survival tree model. Significance and limitations confirmed in the research process were presented as policy suggestions and future research directions.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.655-662
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• 2010

Desertification has been expanding with a remarkable speed across the Northeast Asia. Desertification in Northeast Asia significantly influences Korea's economy and environmental health conditions in recent years. For these reasons, a number of non-governmental organizations (NGOs) in Korea have carried out the reforestation projects to combat desertification in China and Mongolia. Several tree plantation projects were implemented in Mongolia and China. The objective of this study was to analyze and evaluate the performance of tree plantation aid projects carried out by Korean NGOs in Mongolia. The performance of tree plantation projects was examined through effectiveness, efficiency, equity and responsiveness of those projects. The performance was analyzed with the survival rate of planted trees and planting cost, the recognitions of Mongolian people. The analysis of the performance showed that the tree plantation cooperation projects carried out by Korean NGOs in Mongolia had comparatively high performance from a larger point of view. Especially, effectiveness and responsiveness of their projects were highly marked in spite of all the difficulties of carrying out the tree plantation. Such a high effectiveness represented the relatively higher survival rates of trees and Mongolian's positive recognition of plantation projects. Furthermore, the responsiveness also turned out to be high with a great satisfaction of the Mongolian people for plantation projects conducted by the Korean NGOs. Survey results indicated that the efficiency and equity of the projects would be increased by promoting the cooperation projects for tree planting throughout Mongolia with reinforcing infrastructures. By comparison between Korean NGOs and Mongolian Government plantation projects, confirmed the importance of sustained financial support and maintenance activities in the plantation sites.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.2
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• pp.129-137
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• 2016

A colonoscopy is important because it detects the presence of polyps in the colon that can lead to colon cancer. How often one needs to repeat a colonoscopy may depend on various factors. The main purpose of this study is to determine personalized surveillance interval of colonoscopy based on characteristics of patients including their clinical information. The clustering analysis using a partitioning around medoids algorithm was conducted on 625 patients who had a medical examination at Korea University Anam Hospital and found several subgroups of patients. For each cluster, we then performed survival analysis that provides the probability of having polyps according to the number of days until next visit. The results of survival analysis indicated that different survival distributions exist among different patients' groups. We believe that the procedure proposed in this study can provide the patients with personalized medical information about how often they need to repeat a colonoscopy.

• Communications for Statistical Applications and Methods
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• v.7 no.2
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• pp.605-616
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• 2000

Three primary interests frequently raised by mortgage companies are introduced and the corresponding statistical approaches for the default probability in mortgage companies are examined. Statistical models considered in this paper are time series, logistic regression, decision tree, neural network, and discrete time models. Usage of the models is illustrated using an artificially modified data set and the corresponding models are evaluated in appropriate manners.

• Proceedings of the KSRS Conference
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• v.2
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• pp.706-709
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• 2006

Cancer is one of the major causes of death; however, the survival rate can be increased if discovered at an early stage for timely treatment. According to the statistics of the World Health Organization of 2002, breast cancer was the most prevalent cancer for all cancers occurring in women worldwide, and it account for 16.8% of entire cancers inflicting Korean women today. In order to classify the type of breast cancer whether it is benign or malignant, this study was conducted with the use of the discriminant analysis and the decision tree of data mining with the breast cancer data disclosed on the web. The discriminant analysis is a statistical method to seek certain discriminant criteria and discriminant function to separate the population groups on the basis of observation values obtained from two or more population groups, and use the values obtained to allow the existing observation value to the population group thereto. The decision tree analyzes the record of data collected in the part to show it with the pattern existing in between them, namely, the combination of attribute for the characteristics of each class and make the classification model tree. Through this type of analysis, it may obtain the systematic information on the factors that cause the breast cancer in advance and prevent the risk of recurrence after the surgery.

• The Korean Journal of Emergency Medical Services
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• v.15 no.3
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• pp.57-70
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• 2011

Purpose : The purpose of this study was to reveal some factors of ROSC & survival for cardiac arrests from sport & leisure activities(CASLs). Methods : A retrospective study of the 1,341 out of hospital cardiac arrests(OHCAs) treated by EMS in Gyeonggi Provincial Fire and Disaster Headquarters from January to December in 2008 was conducted. The primary end-point was admission to emergency room. To clarify the factors through comparison of CASLs(n=58) with ROSCs & survivals(n=58), Answer Tree analysis for data mining with the CHAID algorithm was performed and alpha was set at .05. Mean, median, and percentile of time intervals, distances, and age on the 58 CASLs, 75 ROSCs, and 27 survivals(patients admitted to emergency room) were analysed. Results : Fourteen CASLs(24.1%), 41 ROSCs(54.7%), 16 survivals(59.3%) were treated with CPR within 5 min., and only 2 CASLs(3.4%), 11 ROSCs(14.7%), 10 survivals(37.0%) were treated with defilbrillation within 10 min. from arrest. If time recording from arrest to defilbrillation, the patients were classified 81.0%($X^2=9.83$, p=.005) into ROSCs & survivals. And the patients with no history, 100.0%($X^2=5.44$, p=.020). The other patients with no intention, 87.5%($X^2=7.00$, p=.024). Whereas the other patients with intention, treated with CPR after 4 min. from arrest were classified 67.2%($X^2=3.99$, p=.046) into CASLs. Conclusion : CPR within 4 minutes was the most important factor that discriminates between CASLs and ROSCs & survivals to record cardiac arrests-defilbrillation time. CPR within 4 min. from arrest, no history, and no intention were factors for improved ROSC & survival.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Korean Journal of Environment and Ecology
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• v.36 no.5
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• pp.496-506
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• 2022

The growth of trees planted through transplantation rapidly decreases immediately after planting due to extreme disturbances such as root cutting and crown damage. Although the growth rate is recovered as time elapses, the time required to restore the original growth varies by species. Therefore, it is necessary to set an appropriate tree management period for survival after transplantation by analyzing each species' annual growth change. In this study, we analyzed the growth amount of deciduous broad-leaf species planted in the area where the riparian ecological belt was formed and proposed the management period based on the results. Slowed growth immediately after planting is a common phenomenon due to root cutting and pruning, the pre-works performed to increase tree survival rate during the transplantation process. Afterward, the original growth rate is recovered as time passes, but the time required may vary depending on the species and planting environment. Most of the trees showed a rapid decrease in growth immediately after transplantation. After that, although it is different for each species, most of them showed a gradual recovery from 2 years onwards. The analysis of the growth rate by tree species confirmed that it took 2 to 4 years, depending on the tree species, to recover the growth level before transplantation after a rapid decrease in growth immediately after transplantation. The results suggest that improving the defect rate of planted trees is necessary to meet the project objectives: ecological restoration and pollutant reduction. It requires setting a tree management period of at least two years and creating an appropriate base environment.

• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.1095-1106
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• 2014

Symbolic data analysis extends the data mining and exploratory data analysis to the knowledge mining, we can suggest the SDA tree model on clinical and genomic data with new knowledge mining SDA approach. Using SDA application for huge genomic SNP data, we can get the correlation the availability of understanding of hidden structure of HCC data could be proved. We can confirm validity of application of SDA to the tree structured progression model and to quantify the clinical lab data and SNP data for early diagnosis of HCC. Our proposed model constructs the representative model for HCC survival time and causal association with their SNP gene data. To fit the simple and easy interpretation tree structured survival model which could reduced from huge clinical and genomic data under the new statistical theory of knowledge mining with SDA.