OBJECTIVE To examine whether greater state-level spending on social and public health services such as income, education and public safety is associated with lower rates of teenage births in USA. DESIGN Ecological study. SETTING USA. PARTICIPANTS 50 states. PRIMARY OUTCOME MEASURE Our primary outcome measure was teenage birth rates. For analyses, we constructed marginal models using rep...

We study the problem of preventing double spending in electronic payment schemes in a distributed fashion. This problem occurs, for instance, when the spending of electronic coins needs to be controlled by a large collection of nodes (e.g., in a peer-to-peer (P2P) system) instead of one central bank. Contrary to the commonly held belief that this is fundamentally impossible, we propose several ...

Recently, Fan et al. proposed a user efficient recoverable off-line e-cash scheme with fast anonymity revoking. They claimed that their scheme could achieve security requirements of an e-cash system such as, anonymity, unlinkability, double spending checking, anonymity control, and rapid anonymity revoking on double spending. They further formally prove the unlinkability and the un-forgeability...

abstract the main purpose of this paper is to obtain the optimal amount of expenses of government relating to the protection of property rights (pprs). to achieve these purposes we have introduced concept of social intelligence with respect to pprs and then developed different growth model from existing literature. in the second step the optimal share of government spending on the pprs is calcu...

IntroductIon The spending for RFID (radio frequency identification) BLOCKINhas BLOCKINbeen BLOCKINincreasing BLOCKINrapidly BLOCKINin BLOCKINrecent years. According to Gartner, global spending on RFID is likely to reach US$3 billion by 2010 (CNET, 2005). In addition, interests continue to grow for the adoption of this mobile computing and commerce device in many different types of applications ...