1,055 research outputs found

    Cometary particulate analyzer

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    A concept for determining the relative abundance of elements contained in cometary particulates was evaluated. The technique utilizes a short, high intensity burst of laser radiation to vaporize and ionize collected particulate material. Ions extracted from this laser produced plasma are analyzed in a time of flight mass spectrometer to yield an atomic mass spectrum representative of the relative abundance of elements in the particulates. Critical aspects of the development of this system are determining the ionization efficiencies for various atomic species and achieving adequate mass resolution. A technique called energy-time focus, which utilizes static electric fields to alter the length of the ion flight path in proportion to the ion initial energy, was used which results in a corresponding compression to the range of ion flight times which effectively improves the inherent resolution. Sufficient data were acquired to develop preliminary specifications for a flight experiment

    Nano-technology: a Disruptive Technology?

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    The term "disruptive technology" as coined by Christensen (1997) refers to a new technology having lower cost and performance measured by traditional criteria, but having higher ancillary performance. Christensen finds that disruptive technologies may enter and expand emerging market niches, improving with time and ultimately attacking established products in their traditional markets. This conception, while useful, is also limiting in several important ways. By emphasizing only "attack from below" Christensen ignores other discontinuous patterns of change which may be of equal or greater importance (Utterback, 1994; Acee, 2001). Further, the true importance of disruptive technology, even in Christensen's conception of it is not that it may displace established products. Rather, it is a powerful means for enlarging and broadening markets and providing new functionality. In this paper nano-technologies will be considered in their roles as both disruptive and more broadly discontinuous or radical innovation. Various impacts will be assessed with emphasis on enlarged and new markets that may be created

    Cardiothoracic surgery at a crossroads: The impact of disruptive technologic change

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    At the beginning of the twenty-first century, cardiothoracic surgery is arguably the most successful of all medical specialties. There are effective treatments including transplantation, for almost all cardiac and thoracic diseases that can be performed with low morbidity and mortality. Cardiothoracic surgeons have mastered technical difficulties through innovation, hard work, planning and skill. Yet in the past decade, the primacy of cardiothoracic surgery has been challenged by new technologies. This paper applies business school theories to examine how cardiothoracic surgeons might best respond to such "disruptive technologies". Otherwise well-managed business and industrial enterprises have had difficulty dealing with disruptive technological change because of well-recognized organizational impediments. Cardiothoracic surgeons must understand the characteristics of disruptive technologies and consider organizational changes that will allow the profession to better adapt to them

    Letter of Support from All Souls Congregational Church

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    Typewritten letter from the chair of the Board of Deacons of All Souls Congregational Church, Bangor, Maine. A vote by members of the Board of Deacons pertaining to the Wilde-Stein Club and the pending gay symposium addressing issues faced by homosexual people supported the action of UMaine Trustees and the right of the freedom of speech

    Geographical interdependence, international trade and economic dynamics: the Chinese and German solar energy industries

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    The trajectories of the German and Chinese photovoltaic industries differ significantly yet are strongly interdependent. Germany has seen a rapid growth in market demand and a strong increase in production, especially in the less developed eastern half of the country. Chinese growth has been export driven. These contrasting trajectories reflect the roles of market creation, investment and credit and the drivers of innovation and competitiveness. Consequent differences in competiveness have generated major trade disputes

    Exploration and exploitation in the presence of network externalities

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    This paper examines the conditions under which exploration of a new, incompatible technologyis conducive to firm growth in the presence of network externalities. In particular, this studyis motivated bythe divergent evolutions of the PC and the workstation markets in response to a new technology: reduced instruction set computing (RISC). In the PC market, Intel has developed new microprocessors bymaintaining compatibilitywith the established architecture, whereas it was radicallyr eplaced byRISC in the workstation market. History indicates that unlike the PC market, the workstation market consisted of a large number of power users, who are less sensitive to compatibilitythan ordinaryusers. Our numerical analysis indicates that the exploration of a new, incompatible technologyis more likelyto increase the chance of firm growth when there are a substantial number of power users or when a new technologyis introduced before an established technologytakes off. (; ; ;

    Churn, Baby, Churn: Strategic Dynamics Among Dominant and Fringe Firms in a Segmented Industry

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    This paper integrates and extends the literatures on industry evolution and dominant firms to develop a dynamic theory of dominant and fringe competitive interaction in a segmented industry. It argues that a dominant firm, seeing contraction of growth in its current segment(s), enters new segments in which it can exploit its technological strengths, but that are sufficiently distant to avoid cannibalization. The dominant firm acts as a low-cost Stackelberg leader, driving down prices and triggering a sales takeoff in the new segment. We identify a “churn” effect associated with dominant firm entry: fringe firms that precede the dominant firm into the segment tend to exit the segment, while new fringe firms enter, causing a net increase in the number of firms in the segment. As the segment matures and sales decline in the segment, the process repeats itself. We examine the predictions of the theory with a study of price, quantity, entry, and exit across 24 product classes in the desktop laser printer industry from 1984 to 1996. Using descriptive statistics, hazard rate models, and panel data methods, we find empirical support for the theoretical predictions

    Dust detection by the wave instrument on STEREO: nanoparticles picked up by the solar wind?

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    The STEREO/WAVES instrument has detected a very large number of intense voltage pulses. We suggest that these events are produced by impact ionisation of nanoparticles striking the spacecraft at a velocity of the order of magnitude of the solar wind speed. Nanoparticles, which are half-way between micron-sized dust and atomic ions, have such a large charge-to-mass ratio that the electric field induced by the solar wind magnetic field accelerates them very efficiently. Since the voltage produced by dust impacts increases very fast with speed, such nanoparticles produce signals as high as do much larger grains of smaller speeds. The flux of 10-nm radius grains inferred in this way is compatible with the interplanetary dust flux model. The present results may represent the first detection of fast nanoparticles in interplanetary space near Earth orbit.Comment: In press in Solar Physics, 13 pages, 5 figure
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