As a non-parametric data mining method, decision tree classification has performed well in many applications. The complexity of the model increases as the decision tree algorithm proceeds to grow the decision tree as the rule of decision making. While the increase of the complexity enhances the accuracy, it degrades the generalization which predicts the unseen data. This phenomenon is called as overfitting. To avoid the overfitting, pruning has been introduced. Pruning enables to make the generalization better, reduces the complexity, and avoids the overfitting. Although various pruning methods have been proposed, selecting the best pruning methods or making balance between complexity and generalization with pruning is not a simple problem. In this paper, we explore the methods of pruning and analyze them to suggest the optimal approach for applications.

본 논문에서는 국내 162개 지반에 대한 전단파속도 주상도, 기반암 깊이 및 지반의 동적변형특성을 획득하여 등가선형해석을 수행한 후 미국 서부해안지역의 지반 특성과 비교 검토하였다. 검토 결과 국내의 일반적인 특성을 가지는 지반과 미국 서부해안지역의 지반은 기반암 깊이와 고유주기가 매우 다름을 확인하였다. 지진응답 해석 결과 단주기 증폭계수 F_a의 경우 1997 UBC 기준의 값보다 크게 산정되었고, 장주기 증폭계수 F_v는 작게 나타나 국내 지반특성에 적합한 증폭계수는 현재 국내 내진설계기준 값과는 매우 다른 경향을 보였다. 따라서, 증폭계수를 재산정하고 설계응답스펙트럼을 개선해야 할 필요성을 확인하였다. 본 논문에서는 현재 이용되고 있는 내진설계기준과 국내 지반특성과의 차이점 파악에 중점을 두었고, 개선방법에 대한 내용은 동반논문(II 지반분류 개선방법, III 설계응답스펙트럼 개선방법)에서 심도있게 논의하였다.

This study intends to classify and analyze the problem of rural villages on the basis of existing ecological and cultural resources. Based on the results of this study, rural villages in Korea can be divided into 4 types - (1) the village abundant in both ecological and cultural resources, (2) the village abundant in only ecological resources, (3) the village abundant in only cultural resources and (4) the village insufficient in two resources. And further, this study found that most ecological resources in rural villages are deteriorated or deteriorating. Even worse, the cultural resources are diminished or diminishing. It is suggested that the ecological and cultural resources need to be taken into account in the process of rural village planning.