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961.
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C. Zeitlin D. M. Hassler R. F. Wimmer-Schweingruber B. Ehresmann J. Appel T. Berger E. Böhm S. Böttcher D. E. Brinza S. Burmeister J. Guo J. Köhler H. Lohf C. Martin D. Matthiä A. Posner S. Rafkin G. Reitz Y. D. Tyler M. Vincent G. Weigle Y. Iwata H. Kitamura T. Murakami 《Space Science Reviews》2016,201(1-4):201-233
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The energy-saving and environmental protection industry has vast development space and huge market increment in China. Selecting appropriate energy-saving and environmental protection enterprises is one of the important decisions of venture capital investment. In the paper,a fuzzy bilateral boundary data envelopment analysis(DEA)model with optimistic coefficient is proposed to select those companies with high financing efficiencies. Based on the characteristics of enterprise financing,undesirable outputs and dual-role factors are considered in the proposed model. The results show that the fifth enterprise has high comprehensive financing efficiencies and always ranks the first when the optimistic coefficients are 0.2,0.5 and 0.8,respectively. In addition,most energy-saving and environmental protection enterprises have not efficient financing efficiencies. There is still much space for improvement. 相似文献
966.
K. Abe H. Fuke S. Haino T. Hams M. Hasegawa A. Horikoshi A. Itazaki K.C. Kim T. Kumazawa A. Kusumoto M.H. Lee Y. Makida S. Matsuda Y. Matsukawa K. Matsumoto J.W. Mitchell A.A. Moiseev J. Nishimura M. Nozaki R. Orito J.F. Ormes N. Picot-Clémente K. Sakai M. Sasaki E.S. Seo Y. Shikaze R. Shinoda R.E. Streitmatter J. Suzuki Y. Takasugi K. Takeuchi K. Tanaka N. Thakur T. Yamagami A. Yamamoto T. Yoshida K. Yoshimura 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) is configured with a solenoidal superconducting magnet and a suite of precision particle detectors, including time-of-flight hodoscopes based on plastic scintillators, a silica-aerogel Cherenkov detector, and a high resolution tracking system with a central jet-type drift chamber. The charges of incident particles are determined from energy losses in the scintillators. Their magnetic rigidities (momentum/charge) are measured by reconstructing each particle trajectory in the magnetic field, and their velocities are obtained by using the time-of-flight system. Together, these measurements can accurately identify helium isotopes among the incoming cosmic-ray helium nuclei up to energies in the GeV per nucleon region. The BESS-Polar I instrument flew for 8.5 days over Antarctica from December 13th to December 21st, 2004. Its long-duration flight and large geometric acceptance allow the time variations of isotopic fluxes to be studied for the first time. The time variations of helium isotope fluxes are presented here for rigidities from 1.2 to 2.5 GV and results are compared to previously reported proton data and neutron monitor data. 相似文献
967.
We estimate the statistic characteristics and extreme deviations of the state vector components for the Ilyushin Il 96–300 systems at automatic landing. 相似文献
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E.G. Cordaro P. Venegas-Aravena D. Laroze 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(7):2290-2299
We report the existence of rapid variations in (effective) geomagnetic cutoff rigidity (Rc) between the equatorial and Antarctic zones adjacent to the Andes Mountains, revealed by the variation rate of geomagnetic cutoff rigidity (VRc) in the period 1975–2010. Our analysis is based on empirical records and theoretical models of the variations in cosmic rays and on the structure of geomagnetic fields. These have given us a different view of variations in Rc in time and space along the 70°W meridian, where secular variations in the geomagnetic field are strongly influenced by the proximity of the South Atlantic Magnetic Anomaly (SAMA), one of the most important characteristics of the terrestrial magnetic field that affects our planet, close from the equator to the 50°S parallel and from South America to South Africa. The VRc presents rapid changes in mid-latitudes where SAMA exerts its influence despite the existence of smooth changes in the geomagnetic field. This shows that these changes occur mainly in the spatial configuration, rather than in the temporal evolution of Rc. The analysis was performed using measurements from the Chilean Network of Cosmic Rays and Geomagnetism Observatories, equipped with BF-3 and latest generation He-3 neutron monitors, Fluxgate magnetometers, geomagnetic reference field (IGRF) and Tsyganenko 2001 model (just for completeness). 相似文献
970.
We investigate the relation between nontrivial spatial concepts such as holes and string loops from a qualitative spatial reasoning perspective. In particular, we concentrate on a family of puzzles dealing with this kind of objects and explain how a loop formed in a string shows a similar behavior to a hole in an object, at least regarding the qualitative constraints it imposes on the solution of the puzzle. Unlike regular holes, however, we describe how string loops can be dynamically created and destroyed depending on the actions on the string. Furthermore, under a Knowledge Representation point of view, we provide a formalization that allows the different puzzle states to be described in terms of string crossings and loops, together with the actions that can be executed for a state transition and the complex effects they cause on the state representation. This implies the consideration of a formal representation of the side effects of actions that create or destroy string loops and the soundness of this representation with respect to the more general representation of string states in knot theory. 相似文献