As modern technologies, such as credit cards, social networking, and online user accounts, become part of the consumer lifestyle, information about an individual s purchasing habits, associations, or other information has become increasingly less private. As a result, the details of consumers lives can now be accessed and shared among third party entities whose motivations lie beyond the grasp, and even understanding, of the original owners. Anonymous Security Systems and Applications: Requirements and Solutions outlines the benefits and drawbacks of anonymous security technologies designed to obscure the identities of users. These technologies may help solve various privacy issues and encourage more people to make full use of information and communication technologies, and may help to establish more secure, convenient, efficient, and environmentally-friendly societies.

The Asia Simulation Conference 2006 (JSST 2006) was aimed at exploring challenges in methodologies for modeling, control and computation in simu lation, and their applications in social, economic, and financial fields as well as established scientific and engineering solutions. The conference was held in Tokyo from October 30 to November 1, 2006, and included keynote speeches presented by technology and industry leaders, technical sessions, organized sessions, poster sessions, and vendor exhibits. It was the seventh annual inter national conference on system simulation and scientific computing, which is organized by the Japan Society for Simulation Technology (JSST), the Chi nese Association for System Simulation (CASS), and the Korea Society for Simulation (KSS). For the conference, all submitted papers were refereed by the international technical program committee, each paper receiving at least two independent reviews. After careful reviews by the committee, 65 papers from 143 submis sions were selected for oral presentation. This volume includes the keynote speakers' papers along with the papers presented at the oral sessions and the organized sessions. As a result, we are publishing 87 papers for the conference in this volume. In addition to the scientific tracts presented, the conference featured keynote presentations by five invited speakers. We are grateful to them for accepting our invitation and for their presentations. We also would like to express our gratitude to all contributors, reviewers, technical program conmiittee members, and organizing committee members who made the conference very successful."