Introduction

This is the second issue on unsaturated soil mechanics and deep geological nuclear waste disposal, corresponding to the International Symposium UNSAT-WASTE 2009 which was organised by Tongji University, China Three Gorges University, State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, and Ecole des Ponts ParisTech. This Symposium was held under the supports of TC6 (unsaturated soils) of ISSMGE, Commission on Radioactive Waste Disposal of ISRM, Commission on Underground Waste Disposal of CSRME, the National Natural Science Foundation of China and Earth Products China (EPC) Limited. Different experiences gained by various countries such as China, France, Germany, Belgium and Spain were presented and exchanged at the Symposium.     

Introduction

A good formwork system enables speedy completion of the concrete structure, following which other subsequent trades can be started. However, the current intuitive judgment approach in the selection of formwork systems cannot assure an optimal and consistent result. Artificial neural networks may improve the selection process. Formwork represents a significant part of the cost of concrete structure construction. Most subsequent trades including internal finishing and external cladding depend on the completion of the building structure. A suitable formwork system is thus crucial for maintaining the smooth flow of the various trades and a proper working sequence of various work activities. Based on data collected from a previous study, it is clear that the key factors affecting the selection of a relevant formwork system include building height and structural system, concrete finish, site conditions, availability of equipment and building shape. Neural network models are developed for the selection of vertical formwork systems using the architecture of the probabilistic neural network (PNN) model. A case study verifies the validity of this approach.     

Introduction

This special supplement of the APA Journal deals with neighborhood revitalization and related planning issues. It is hoped that the articles contained herein will contribute to the ongoing debate on neighborhood planning and provide insights into some of the implications of a neighborhood-based urban policy. Although it is true that only a very small portion of federal housing, community development, and related resources are now allocated directly to neighborhoods or routed through neighborhood development organizations, the federal interest in neighborhoods is clearly on the rise.