9,377 research outputs found

    The Collapse of Interwar Vienna: Oskar Morgenstern’s Community, 1925 - 1950

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    From the perspective of science, art and intellectual life in general, Interwar Vienna was one of the most vibrant communities in modern European history. Within the field of economics, it was home to, amongst others, Ludwig von Mises, Friedrich von Hayek, Hans Mayer, Gottfried Haberler, Fritz Machlup, Oskar Morgenstern, Karl Menger and Abraham Wald. The community flourished after the end of World War I, and then began to suffer in the early 1930’s as a result of growing political instability and rising anti-semitism. With the Anschluss of Austria by the Third Reich in March 1938, it collapsed completely, never to recover. Drawing on the personal papers of two key participants, Oskar Morgenstern and Karl Menger, and also on the archives of the Rockefeller Foundation, this paper provides a portrait of that community, chronicling its evolution and dramatic collapse. Particular attention is paid to the milieu surrounding Morgenstern, both as director of the Rockefeller-funded Austrian Institute for Business Cycle Research and as philosophical “dissident”. In collaborating with mathematicians Menger, Wald and, later, John von Neumann, he gradually forsook his Austrian theoretical legacy. The account detailed here shows conflict and tension to have been central to both the life and death of this fabled community.

    Auroral zone absorption of radio waves transmitted via the ionosphere

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    A discussion of the design for a new antenna system for the transmitter stations is presented together with the measurements and power computation made on the old and new antennas. In the 12 mc back-scatter program at College, the technique used to measure the amplitude of each individual echo and reanalysis of the range distribution previously reported are discussed. Revisions in the techniques of observation of visual auroras and the methods of recording the data for analysis are described in detail.Section I Purposes – Section II Abstract – Section III Publications, Lectures, Reports and Conferences – Section IV Factual Data : Task A ; Task B – Section V Conclusions and Recommendations – Section VI Plans for Next Quarter – Section VII Personnel – Section VIII Appendix : Visual Observations of Aurora in Alaska 1953-1954 / C.T. Elvey ; References ; Figures 1 to 17Ye

    Electro-expulsive separation system

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    An electro-expulsive system has one or more overlapped conductors, each comprising a flexible ribbon conductor, which is folded back on itself. The conductors are embedded in an elastomeric material. Large current pulses are fed to the conductors from power storage units. As a result of the antiparallel currents, the opposed segments of a conductor are forcefully separated and the elastomeric material is distended. Voids in the elastomer aid the separation of the conductor segments. The distention is almost instantaneous when a current pulse reaches the conductor and the distention tends to remove any solid body on the surface of the elastomeric material

    Scalar meson spectroscopy: achievements and traps

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    Interactions in three coupled channels: pi-pi, K-anti K and sigma-sigma have been investigated in a wide two-pion effective mass region from the pi-pi threshold up to 1600 MeV. Analytical structure of amplitudes in all channels has been studied. It was shown that its knowledge is necessary to understand spectrum of scalar mesons and their nature.Comment: 6 pages, Invited talk at YITP Workshop on Possible Existence of the sigma meson and it Implications to Hadron Physics (sigma-meson 2000), Kyoto, Japan, 12-14 Jun 200

    Microwave integrated circuits for space applications

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    Monolithic microwave integrated circuits (MMIC), which incorporate all the elements of a microwave circuit on a single semiconductor substrate, offer the potential for drastic reductions in circuit weight and volume and increased reliability, all of which make many new concepts in electronic circuitry for space applications feasible, including phased array antennas. NASA has undertaken an extensive program aimed at development of MMICs for space applications. The first such circuits targeted for development were an extension of work in hybrid (discrete component) technology in support of the Advanced Communication Technology Satellite (ACTS). It focused on power amplifiers, receivers, and switches at ACTS frequencies. More recent work, however, focused on frequencies appropriate for other NASA programs and emphasizes advanced materials in an effort to enhance efficiency, power handling capability, and frequency of operation or noise figure to meet the requirements of space systems

    The Democratization of U.S. Research and Development after 1980

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    Using Compustat data, we document that prior to 1980, large R&D per-forming firms had higher R&D intensity (R&D/Sales) than small firms in the same industries. Over the course of the next two decades, in these same in-dustries, small firms came to rival and even surpass large firms in terms of R&D intensity. During this period, corporate R&D intensity nearly doubled and most of the aggregate increase is due to the substantial increase in R&D intensity among small firms. Little of the change in composition is explained by changes in the industrial distribution of R&D. Why did small firms increase their R&D after 1980 and not before? We argue that, after 1980, small firms were able to compete on better terms in industries already dominated by large firms. We show that the patterns we observe in the data are consistent with a straightforward dynamic model of R&D with falling barriers to entry. But what barriers fell? We argue the shift in R&D intensity by small firms was largely due to the electronics revolution. Prior to the 1980s, a large corporate sales and clerical force was an essential factor for the rapid and widespread distribution of new products. This technology clearly favored large, established firms. But the electronics revolution obviated the need for these factors, making entry easier.R&D, barriers to entry, innovation
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