• 한국환경과학회지
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• 제5권3호
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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.

• 한국군사과학기술학회지
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• 제27권1호
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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.

• 한국산림과학회지
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• 제99권5호
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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.

• 대한산업공학회지
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• 제42권2호
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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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• 제7권2호
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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.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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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.

• 한국응급구조학회지
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• 제15권3호
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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.

• 한국산림과학회지
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• 제108권4호
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• pp.513-521
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• 2019

본 연구는 전국 난대상록활엽수종의 조림지에 대한 생육환경 및 입지환경 특성과 활착률간의 관계특성으로부터 조림적지 의사결정 기초자료를 제공하고자 하였다. 1997년부터 후박나무(Machilus thunbergii), 구실잣밤나무(Castanopsis sieboldii) 등 난대상록활엽수 10종의 신규 조림지 180ha의 148개 조사구에 대한 활착률을 모니터링 한 결과 평균 활착률은 67.0±26.9%이었다. 활착률 편차가 크게 나타난 원인은 조림 적지에 관한 실증적 현지 검증이 부족한 상황에서 다양한 입지를 대상으로 시험 조림이 이루어진 결과로 판단된다. 각 조사구별 11개 생육환경 및 입지환경 특성, 조림전후 강수 등의 정성적 설명요인과 활착률의 정량적 요인 간의 관계특성으로부터 수량화 이론 I에 따른 활착률에 대한 기여도를 분석한 결과, 조림지 상층임분 울폐도, 풍노출도, 조림 전 누적 강수량, 경사도 등의 순으로 높게 나타났다.

• 한국환경생태학회지
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• 제36권5호
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• pp.496-506
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• 2022

이식 과정을 통해 식재된 수목은 뿌리 절단, 수관 훼손과 같은 극단적인 교란으로 인해 식재 직후 생장량은 급격히 감소한다. 이후 시간이 경과하면서 원래의 생장량을 회복하는데 이때 소요되는 시간은 수종별로 차이가 있다. 따라서 이식 후 활착을 위한 수목관리를 위해 수종별 연간생장량의 변화를 분석하여 적정 관리 기간을 설정할 필요가 있다고 판단하였다. 이에 본 연구에서는 수변생태벨트 조성 지역에 식재된 낙엽활엽수를 대상으로 생장량을 분석하고 그 결과를 바탕으로 적정 관리 기간을 제안하고자 하였다. 이식과정에서 수목 활착율을 높이기 위해 시행하는 사전 작업인 뿌리돌림, 단근, 가지치기 등으로 인해 식재 직후의 생장량 둔화는 일반적인 현상이다. 이후 시간이 경과하면서 원래의 생장량을 회복하게 되는데, 소요되는 시간은 수종별, 식재 환경 등에 따라 차이가 존재할 수 있다. 연구결과 대부분의 수목은 이식 직후 급격한 생장량 감소를 보이는 것으로 나타났으며. 이후 수종별로 상이하긴 하나 대부분 2년 이후부터 서서히 생장량을 회복하는 것으로 나타났다. 수종별 생장량을 분석한 결과 공통적으로 이식 직후 급격한 생장량 감소를 보인 후, 이식전의 생장 수준을 회복하기 까지는 수종에 따라 2~4년 정도의 시간이 필요한 것으로 확인되었다. 결과적으로, 생태복원 및 오염물질 저감이라는 본 사업의 목적에 부합하기 위해서는 식재한 수목의 하자율 개선이 필요하며, 이를 위해서는 적정한 기반환경을 조성하는 것 외에 최소 2년간의 수목 관리기간을 설정하는 것이 필요하다.

• Journal of the Korean Data and Information Science Society
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• 제25권5호
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• pp.1095-1106
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• 2014

본 연구에서는 악성간암환자의 생존기간에 영향을 주는 인자를 찾기 위하여 반응변수를 악성간암 환자의 생존을 임상변수의 정보와 SNP유전인자를 통합한 자료를 대상으로 이해하기 쉬운 나무구조 생존모형과 심볼릭자료분석을 실시하여 영향을 주는 유의한 인자 뿐 아니라 그 임계치를 구하여 임상적으로 유용한 결과를 찾아 임상에 적용하는 것이 목적이다. 악성간암환자의 임상자료를 계량화하여 통계적 예후진단 모형을 구함으로써 임상변수 간 숨겨진 변수간의 관계를 규명하고 생존기간 군에 따른 예측 분류모형을 구하여 현시적으로 진단후 예후에 영향을 주는 중요 임상변수와 유전체변수 그 임계치를 구하여 임상에서의 치료계획에 중요한 근거를 제시했다. 심볼릭데이터 분석 결과 정상, 만성 간염, 간염, 악성간염 등의 4개 군으로 구성된 1840명의 대상자를 분석 5 유전체의 20개 SNP가 밝혀진 바 있다. 즉 IL10-ht2가 악성간암의 발병에 매위 강한 관련이 있고 TGFB L10P-Prosms가 만성 간염 환자 중 악성간암 발생 위험을 줄여주는 유전체로 밝혀졌다. SNP변수와 질병군의 컴셉트 변수에 따라 상관정도를 원의 반지름 길이로 상대적으로 나타내 줌으로써 가장 판별력 있는 심볼릭변수를 상대적으로 비교할 수 있었다. 임상자료와 유전체자료를 통합하여 심볼릭 나무구조 생존모형을 구하여 생존기간을 군으로 한 나무구조모형을 유의한 변수와 기준치와 함께 구할 수 있었다.