15,154 research outputs found

    Social Dilemmas

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    A near-earth optical communications terminal with a corevolving planetary sun shield

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    The umbra of a planet may serve as a sun shield for a space based optical communications terminal or for a space based astronomical observatory. An orbit that keeps the terminal or observatory within the umbra is desirable. There is a corevolution point behind every planet. A small body stabilized at the planet corevolution point will revolve about the sun at the same angular velocity as the planet, always keeping the planet between itself and the sun. This corevolution point is within the umbra of Mars but beyond the end of the umbra for Mercury, Venus, and earth. The Mars corevolution point is an ideal location for an astronomical observatory. There Mars obstruct less than 0.00024 percent of the sky at any time, and it shades the observatory completely from the sun. At the earth corevolution point, between 51 and 84 percent of the solar disk area is blocked, as is up to 92 percent of the sunlight. This provides a reduction from 3 dB to 11 dB in sunlight that could interfere with optical communications if scattered directly into the detectors. The variations is caused by revolution of the earth about the earth-moon barycenter

    Fraunhofer filters to reduce solar background for optical communications

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    A wavelength that lies within a spectral interval of reduced solar emission (a Fraunhofer line) can carry optical communications with reduced interference from direct or reflected background sunlight. Suitable Fraunhofer lines are located within the tuning range of good candidate lasers. The laser should be tunable dynamically to track Doppler shifts in the sunlight incident on any solar system body that may appear in the background as viewed by the receiver. A Fraunhofer filter used with a direct-detection receiver should be tuned to match the Doppler shifts of the source and background. The required tuning calculated here for various situations is also required if, instead, one uses a heterodyne receiver with limited post-detection bandwidth

    Methods of small group research

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    Developing an inter-university partnership: The importance of relationally-connected leaders

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    We have been involved in an inter-university partnership that supports, contributes to, and influences our own and others’ thinking and actions. As we have collaborated on teaching, learning, and research in the field of educational leadership, we recognise that we have developed our own leadership practice and created opportunities for others to do so. The partnership in which academics and students from the University of Central Oklahoma and the University of Waikato have been participating has evolved as a flexible and innovative endeavor over an eighteen month period. In this relatively brief time, we have discovered there are considerable possibilities for the partnership to be developed in a number of ways that will benefit academics, students, and our respective institutions. In this paper, we examine and discuss the findings generated by our initial inquiry as we seek to make sense of our inter university partnership in order to sustain and progress it. Our leadership during the initial phases of the partnership appears to have been a key element in its success. We have found that the presence of a relational connectedness has influenced and enhanced our own leadership practice and subsequently the quality of the partnership. It has enabled us to facilitate the growth of a community of practice and generate academic collaboration

    Challenging US Country of Origin Labelling at the World Trade Organization: The Law, The Issues and The Evidence

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    Canada and Mexico are formally challenging US country of origin (COOL) legislation at the World Trade Organization. The industries most affected by COOL are beef and pork. The effect of COOL on North American cross border supply chains is outlined. The areas of international trade law upon which a challenge could be mounted are explained and the key issues that a disputes panel would have to determine indicated. The nature of the evidence that may be required to bolster Canada’s case is outlined.country of origin, marks of origin, protectionism, Technical Barriers to Trade, supply chains, WTO, Agribusiness, Agricultural and Food Policy, Demand and Price Analysis, International Relations/Trade, Marketing,

    Challenging US Country of Origin Labelling at the WTO: The Law, the Issues and the Evidence

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    COOL, WTO, labelling, despite, Agricultural and Food Policy, International Relations/Trade,

    Local Industrial Conditions and Entrepreneurship: How Much of the Spatial Distribution Can We Explain?

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    Why are some places more entrepreneurial than others? We use Census Bureau data to study local determinants of manufacturing startups across cities and industries. Demographics have limited explanatory power. Overall levels of local customers and suppliers are only modestly important, but new entrants seem particularly drawn to areas with many smaller suppliers, as suggested by Chinitz (1961). Abundant workers in relevant occupations also strongly predict entry. These forces plus city and industry fixed effects explain between sixty and eighty percent of manufacturing entry. We use spatial distributions of natural cost advantages to address partially endogeneity concerns.Entrepreneurship, Industrial Organization, Agglomeration, Labor Markets, Input-Output Flows, Innovation, Research and Development, Patents.
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