450 research outputs found

    Impacts of the Information-technology Revolution on Japanese Manufacturer-supplier Relationships

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    'Vertical keiretsu', characterized by suppliers' willingness to make customized investments and their long-term relationships with manufacturers, had been recognized as an important source of strength in Japanese industries. Our model predicts that, in contrast to the recent popular argument, the information-technology revolution can strengthen 'vertical keiretsu'. This is because the efficiency of designing customized parts is significantly enhanced if suppliers undertake a substantial level of IT investments such as the introduction of 3D CAD systems, and the customized nature of such investments could reduce the number of potential suppliers. Our interviews with Japanese manufacturers provide a support to this prediction.Customized investment, Information technology, Japanese firm, Vertical Keiretsu, Subcontracting

    BLASTbus electronics: general-purpose readout and control for balloon-borne experiments

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    We present the second generation BLASTbus electronics. The primary purposes of this system are detector readout, attitude control, and cryogenic housekeeping, for balloon-borne telescopes. Readout of neutron transmutation doped germanium (NTD-Ge) bolometers requires low noise and parallel acquisition of hundreds of analog signals. Controlling a telescope's attitude requires the capability to interface to a wide variety of sensors and motors, and to use them together in a fast, closed loop. To achieve these different goals, the BLASTbus system employs a flexible motherboard-daughterboard architecture. The programmable motherboard features a digital signal processor (DSP) and field-programmable gate array (FPGA), as well as slots for three daughterboards. The daughterboards provide the interface to the outside world, with versions for analog to digital conversion, and optoisolated digital input/output. With the versatility afforded by this design, the BLASTbus also finds uses in cryogenic, thermometry, and power systems. For accurate timing control to tie everything together, the system operates in a fully synchronous manner. BLASTbus electronics have been successfully deployed to the South Pole, and own on stratospheric balloons

    Volume 2, Number 1 - May 1956

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    The Entropy (also published as the Providence College Journal of Physics and Chemistry) was an undergraduate scholarship journal published by the Phi Chi Club of Providence College. (Volume 2, Number 1 - May 1956 - 16 pages in total.

    BICEP3: a 95 GHz refracting telescope for degree-scale CMB polarization

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    BICEP3 is a 550 mm-aperture refracting telescope for polarimetry of radiation in the cosmic microwave background at 95 GHz. It adopts the methodology of BICEP1, BICEP2 and the Keck Array experiments - it possesses sufficient resolution to search for signatures of the inflation-induced cosmic gravitational-wave background while utilizing a compact design for ease of construction and to facilitate the characterization and mitigation of systematics. However, BICEP3 represents a significant breakthrough in per-receiver sensitivity, with a focal plane area 5×\times larger than a BICEP2/Keck Array receiver and faster optics (f/1.6f/1.6 vs. f/2.4f/2.4). Large-aperture infrared-reflective metal-mesh filters and infrared-absorptive cold alumina filters and lenses were developed and implemented for its optics. The camera consists of 1280 dual-polarization pixels; each is a pair of orthogonal antenna arrays coupled to transition-edge sensor bolometers and read out by multiplexed SQUIDs. Upon deployment at the South Pole during the 2014-15 season, BICEP3 will have survey speed comparable to Keck Array 150 GHz (2013), and will significantly enhance spectral separation of primordial B-mode power from that of possible galactic dust contamination in the BICEP2 observation patch.Comment: 12 pages, 5 figures. Presented at SPIE Astronomical Telescopes and Instrumentation 2014: Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VII. To be published in Proceedings of SPIE Volume 915

    Ceramics in gas turbine: Powder and process characterization

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    Some of the intrinsic properties of various forms of Si3N4 and SiC are listed and limitations of such materials' availability are pointed out. The essential features/parameters to characterize a batch of powder are discussed including the standard techniques for such characterization. In process characterization, parameters in sintering, reaction sintering, and hot pressing processes are discussed including the factors responsible for strength limitations in ceramic bodies. Significant improvements in material properties can be achieved by reducing or eliminating the strength limiting factors with consistent powder and process characterization along with process control

    A high voltage power supply for the AE-C and D low energy electron experiment

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    A description is given of the electrical and mechanical design and operation of high voltage power supplies for space flight use. The supply was used to generate the spiraltron high voltage for low energy electron experiment on AE-C and D. Two versions of the supply were designed and built; one design is referred to as the low power version (AE-C) and the other as the high power version (AE-D). Performance is discussed under all operating conditions

    Design and construction of a carbon fiber gondola for the SPIDER balloon-borne telescope

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    We introduce the light-weight carbon fiber and aluminum gondola designed for the SPIDER balloon-borne telescope. SPIDER is designed to measure the polarization of the Cosmic Microwave Background radiation with unprecedented sensitivity and control of systematics in search of the imprint of inflation: a period of exponential expansion in the early Universe. The requirements of this balloon-borne instrument put tight constrains on the mass budget of the payload. The SPIDER gondola is designed to house the experiment and guarantee its operational and structural integrity during its balloon-borne flight, while using less than 10% of the total mass of the payload. We present a construction method for the gondola based on carbon fiber reinforced polymer tubes with aluminum inserts and aluminum multi-tube joints. We describe the validation of the model through Finite Element Analysis and mechanical tests.Comment: 16 pages, 11 figures. Presented at SPIE Ground-based and Airborne Telescopes V, June 23, 2014. To be published in Proceedings of SPIE Volume 914

    Globalization of innovation activity by transnational corporations: and its importance in the present economic crisis

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    The research aims to investigate the process of globalizing innovation activity conducted by transnational corporations (TNCs), in a wider context of economic changes outside and inside companies. The process has been triggered by decentralization and internationalization of R&D, “creative transition†of foreign subsidiaries as well as implementing research networks and the open innovation model of TNCs’ innovation activity. Under the present economic crisis some slowdown and reorientation of innovation programs are implemented in order to reduce their costs and increase effectiveness. The globalization of corporate innovation activity can contribute to reaching some of TNCs’ goals both under the present crisis and the future revival of the world economy.Globalization, innovations, economic crisis, TNC., International Development, D21, F23, L22, O32,
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