Recent years have witnessed the explosion of online social networks (OSNs). They provide powerful IT-innovations for online social activities such as organizing contacts, publishing contents, and sharing interests between friends who may never meet before. As more and more people become the active users of online social networks, one may ponder questions such as: (1) Do OSNs indeed improve our ...

We illustrate the use of functional system speci cations and their re nement in the development of system components by a simple case study The development includes the modular speci cation re nement and veri cation of system components We start the development with an informal description of the tasks of the case study and then step by step carry out the tasks formally The informal requirement...

Studies of human spatial behavior and life spaces are useful because they allow a better understanding of the relationship between people and environment. In an era when there is growing public pressure to understand this relationship, studies of life spaces may provide insight into the environmental sensitivity of different groups of people. In this article, we propose a method for characteriz...

This paper is the sequel of the paper [4], in which we established the arithmetic volume function of C-hermitian Q-invertible sheaves and proved its continuity. The continuity of the volume function has a lot of applications as treated in [4]. In this paper, we would like to consider its continuous extension over R. CONTENTS Introduction 1 1. A multi-indexed version of the fundamental estimatio...