Practical Distributed Control Synthesis

Classic distributed control problems have an interesting dichotomy: they are either trivial or undecidable. If we allow the controllers to fully synchronize, then synthesis is trivial. In this case, controllers can effectively act as a single controller with complete information, resulting in a trivial control problem. But when we eliminate communication and restrict the supervisors to locally available information, the problem becomes undecidable. In this paper we argue in favor of a middle way. Communication is, in most applications, expensive, and should hence be minimized. We therefore study a solution that tries to communicate only scarcely and, while allowing communication in order to make joint decision, favors local decisions over joint decisions that require communication.Comment: In Proceedings INFINITY 2011, arXiv:1111.267

System quality, user satisfaction, and perceived net benefits of mobile broadband services

The continued decline of voice revenues is pushing mobile operators in Taiwan turn into data and content services for exploring new revenue opportunities and raising ARPU. This study aims to discuss the critical determinants of the internet user's adoption of 3.5G mobile broadband services in Taiwan. The theoretical framework employed in the study is Information System Success Model (DeLone & McLean, 2003; Chae et al.,2002), which is operationally defined with mobile web-services measurement scales. The study attempts to identify how the system quality of 3.5G mobile broadband services affects the customer satisfaction and their perceived net benefit. With the affordable mobile broadband connectivity, 3.5 G access or HSDPA in Taiwan has played a major role in the burgeoning mobile Internet market. HSDPA (High Speed Downlink Packet Access) could be viewed as an advanced version of WCDMA wireless network. HSDPA ideally provides mobile data services up to 14.4 Mbps for the downlinks and up to 5.8 Mbps for the uplinks. According to TWNIC, the number of cell phone subscribers in Taiwan has grown up to 23 million by March 2009 with a 100% penetration rate Yet, among cell phone subscribers there were only 1.6 million users adopting mobile broadband services. --Mobile Broadband Services,IS Success Model,Customer Satisfaction,Net Benefits