6,738 research outputs found

    Transitioning from analog to digital communications: An information security perspective

    Get PDF
    A summary is given of the government's perspective on evolving digital communications as they affect secure voice users and approaches for operating during a transition period to an all digital world. An integrated architecture and a mobile satellite interface are discussed

    Toward a North American Standard for Mobile Data Services

    Get PDF
    The rapid introduction of digital mobile communications systems is an important part of the emerging digital communications scene. These developments pose both a potential problem and a challenge. On one hand, these separate market driven developments can result in an uncontrolled mixture of analog and digital links which inhibit data modem services across the mobile/Public Switched network (PSTN). On the other hand, the near coincidence of schedules for development of some of these systems, i.e., Digital Cellular, Mobile Satellite, Land Mobile Radio, and ISDN, provides an opportunity to address interoperability problems by defining interfaces, control, and service standards that are compatible among these new services. In this paper we address the problem of providing data services interoperation between mobile terminals and data devices on the PSTN. The expected data services include G3 Fax, asynchronous data, and the government's STU-3 secure voice system, and future data services such as ISDN. We address a common architecture and a limited set of issues that are key to interoperable mobile data services. We believe that common mobile data standards will both improve the quality of data service and simplify the systems for manufacturers, data users, and service providers

    The Contribution and Potential of Data Harmonization for Cross-National Comparative Research

    Get PDF
    The promise of empirical evidence to inform policy makers about their population's health, wealth, employment and economic well being has propelled governments to invest in the harmonization of country specific micro data over the last 25 years. We review the major data harmonization projects launched over this period. These projects include the Luxembourg Income Study (LIS), the Cross-National Equivalent File (CNEF), the Consortium of Household Panels for European Socio-Economic Research (CHER), the European Community Household Panel (ECHP), the European Union Statistics on Income and Living Conditions (EU-SILC), and the Survey of Health, Aging and Retirement in Europe (SHARE). We discuss their success in providing reliable data for policy analysis and how they are being used to answer policy questions. While there have been some notable failures, on the whole these harmonization efforts have proven to be of major value to the research community and to policy makers.

    Locally Complete Path Independent Choice Functions and Their Lattices

    Get PDF
    The concept of path independence (PI) was first introduced by Arrow (1963) as a defense of his requirement that collective choices be rationalized by a weak ordering. Plott (1973) highlighted the dynamic aspects of PI implicit in Arrow's initial discussion. Throughout these investigations two questions, both initially raised by Plott, remained unanswered. What are the precise mathematical foundations for path independence? How can PI choice functions be constructed? We give complete answers to both these questions for finite domains and provide necessary conditions for infinite domains. We introduce a lattice associated with each PI function. For finite domains these lattices coincide with locally lower distributive or meet-distributive lattices and uniquely characterize PI functions. We also present an algorithm, effective and exhaustive for finite domains, for the construction of PI choice functions and hence for all finite locally lower distributive lattices. For finite domains, a PI function is rationalizable if and only if the lattice is distributive. The lattices associated with PI functions that satisfy the stronger condition of the weak axiom of revealed preference are chains of Boolean algebras and conversely. Those that satisfy the strong axiom of revealed preference are chains and conversely.

    Defining interoperability standards: A case study of public health observatory websites

    Get PDF
    The Association of Public Health Observatories (APHO) is a group of region-based health-information providers. Each PHO publishes health-related data for their specific region. Each observatory has taken a national lead in one or more key health area - such as 'cancer' or Obesity'. In 2003, a project was initiated to develop 'interoperability' between public health observatory websites, so the national resources published by one lead observatory could be found on the websites for each other PHO. The APHO interoperability project defined a set of requirements for each PHO - websites should comply with the current government data standards and provide webservices to allow data to be searched in real-time between different PHOs. This thesis describes the production of an interoperable website for the North East Public Health Observatory (NEPHO) and the problems faced during implementation to comply with the APHO interoperability requirements. The areas of interoperability, e-Government and metadata were investigated specifically in suitability for NEPHO and an action list of tasks necessary to achieve the project aims was drawn up. This project has resulted in the successful introduction of a new NEPHO website that complies with the APHO and e-Govemment requirements, however interoperability with other organisations has been difficult to achieve. This thesis describes how other organisations approached the same APHO interoperability criteria and questions whether the national project governance could be improved

    On Setting Near-term Climate Policy while the Dust Begins to Settle: The Legacy of the Stern Review

    Get PDF
    We review the explosion of commentary that has followed the release of the Stern Review: The Economics of Climate Change, and agree with most of what has been written. The Review is right when it argues on economic grounds for immediate intervention to reduce emissions of greenhouse gases, but we feel that it is right for the wrong reasons. A persuasive case can be made that climate risks are real and increasingly threatening. If follows that some sort of policy will be required, and the least cost approach necessarily involves starting now. Since policy implemented in 2007 will not “solve” the climate problem, near term interventions can be designed to begin the process by working to avoid locking in high carbon investments and providing adequate incentives for carbon sequestration. We argue that both objectives can be achieved without undue economic harm in the near term by pricing carbon at something on the order of $15 per ton as long as it is understood that the price will increase persistently and predictably at something like the rate of interest; and we express support for a tax alternative to the usual cap-and-trade approach.Stern Review, climate change, climate policy, social discount rate; risk and equity aversion

    Growth of entire functions

    Get PDF
    corecore