5,254 research outputs found

    Unified clustering and communication protocol for wireless sensor networks

    Get PDF
    In this paper we present an energy-efficient cross layer protocol for providing application specific reservations in wireless senor networks called the “Unified Clustering and Communication Protocol ” (UCCP). Our modular cross layered framework satisfies three wireless sensor network requirements, namely, the QoS requirement of heterogeneous applications, energy aware clustering and data forwarding by relay sensor nodes. Our unified design approach is motivated by providing an integrated and viable solution for self organization and end-to-end communication is wireless sensor networks. Dynamic QoS based reservation guarantees are provided using a reservation-based TDMA approach. Our novel energy-efficient clustering approach employs a multi-objective optimization technique based on OR (operations research) practices. We adopt a simple hierarchy in which relay nodes forward data messages from cluster head to the sink, thus eliminating the overheads needed to maintain a routing protocol. Simulation results demonstrate that UCCP provides an energy-efficient and scalable solution to meet the application specific QoS demands in resource constrained sensor nodes. Index Terms — wireless sensor networks, unified communication, optimization, clustering and quality of service

    The Democratization of Invention in the American South: Antebellum and Post Bellum Technology Markets in the United States

    Get PDF
    Patenting expanded rapidly across the post bellum South as its transportation network filled in and city growth extended markets. This was consistent with Sokoloff and Khan (1990), who demonstrated the elastic supply of patentable ideas in early America. Successful innovation required that inventors could or did sell their property rights through "assignment" to those who commercialized new technology. The assignment characteristics of 1912 southern patents were examined. Southern "border" state patents had a higher rate of marketable assignments than those issued to residents in the Deep South. Greater commercialization of patents in border state cities accounted for most of this difference.post-bellum South, invention, patents

    Major Factors Influencing the Competitiveness of the California Strawberry Subsector

    Get PDF
    With its nearly year-round supply and 83% market share, the California strawberry subsector dominates production and distribution of fresh strawberries in North America. The subsector has achieved its leading position among competitive production regions (e.g., Florida and Oregon) through the development and interaction of several factors. These factors include the following: superior agro-ecological conditions, economies of size, technological innovation, favorable demand conditions, marketing flexibility, and support infrastructure.Industrial Organization,

    The Impact of Income and Family Structure on Delinquency

    Get PDF
    There is no more important issue in the economics of the family than the impact of parents on the behavior of their children. By providing rewards and imposing constraints, parents seek to affect their children’s behavior. The explanation of these actions is that the child’s conduct directly enters into the parent’s utility function. In this paper, we use that framework to explore the role of parental control over his or her child’s delinquent behavior. Using data from the National Longitudinal Survey of Youth, we estimate the impact of family income and various dimensions of family structure on a youth’s contact with the criminal justice system between the ages of 14 and 22. From this analysis, we conclude that the single most important factor affecting these measures of delinquency is the presence of his father in the home. All other factors, including family income, are much less important.family structure; delinquency; role of fathers; role of mothers

    Energy-aware peering routing protocol for indoor hospital body area network communication

    Get PDF
    The recent research in Body Area Networks (BAN) is focused on making its communication more reliable, energy efficient, secure, and to better utilize system resources. In this paper we propose a novel BAN network architecture for indoor hospital environments, and a new mechanism of peer discovery with routing table construction that helps to reduce network traffic load, energy consumption, and improves BAN reliability. We have performed extensive simulations in the Castalia simulation environment to show that our proposed protocol has better performance in terms of reduced BAN traffic load, increased number of successful packets received by nodes, reduced number of packets forwarded by intermediate nodes, and overall lower energy consumption compared to other protocols
    corecore