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91.
Griliches’ knowledge production function has been increasingly adopted at the regional level where location-specific conditions drive the spatial differences in knowledge creation dynamics. However, the large majority of such studies rely on a traditional regression approach that assumes spatially homogenous marginal effects of knowledge input factors. This paper extends the authors’ previous work (Kang and Dall’erba in Int Reg Sci Rev, 2015. doi: 10.1177/0160017615572888) to investigate the spatial heterogeneity in the marginal effects by using nonparametric local modeling approaches such as geographically weighted regression (GWR) and mixed GWR with two distinct samples of the US Metropolitan Statistical Area (MSA) and non-MSA counties. The results indicate a high degree of spatial heterogeneity in the marginal effects of the knowledge input variables, more specifically for the local and distant spillovers of private knowledge measured across MSA counties. On the other hand, local academic knowledge spillovers are found to display spatially homogenous elasticities in both MSA and non-MSA counties. Our results highlight the strengths and weaknesses of each county’s innovation capacity and suggest policy implications for regional innovation strategies. 相似文献
92.
93.
A short survey prepared by the Russian Commission on Atmospheric Radiation contains the most significant results of work in the field of atmospheric-radiation studies performed in 2011–2014. It is part of the Russian National Report on Meteorology and Atmospheric Sciences prepared for the International Association on Meteorology and Atmospheric Sciences (IAMAS)1. During this period, the Russian Commission on Atmospheric Radiation, jointly with the concerned departments and organizations, organized two International Symposiums on Radiation and Dynamics (ISARD-2011 and ISARD-2013). At these conferences, the central problems in modern atmospheric physics were discussed: radiative transfer (RT) and atmospheric optics; greenhouse gases, clouds, and aerosols; remote methods of measurements; and new measurement data. This survey presents six directions covering the whole spectrum of investigations performed in the field of atmospheric radiation. 相似文献
94.
M. A. Zel’dovich Yu. I. Logachev G. M. Surova K. Kecskemety I. S. Veselovskii 《Astronomy Reports》2016,60(7):687-693
The energy spectra and relative abundances of 3He, 4He, C, O, and Fe ions with energies of ~0.04–2 MeV/nucleon are studied using data from the ULEIS instrument on board the ACE spacecraft obtained during quiescent periods in 2006–2012. During the unique, prolonged minimum between cycles 23 and 24, 35 quiescent periods were distnguished, during which solar-wind flows from near-equatorial coronal holes (CHs) were detected. It is shown that the C/O and Fe/O ratios for suprathermal ions correspond to the relative abundances of the corresponding thermal ions in the fast and slow (Maxwellian) solar wind (SWICS/ACE), while the 4He/O ratio exceeds the corresponding ratio in the solar wind by a factor of two. The intensities of the 3He, 4He, C, O, and Fe suprathermal ions in outflows from CHs grow with the speed of the solar wind. This indicates that, in periods ofminimumsolar activity, suprathermal ions from CHs represent a high-temperature “tail” of the solar wind. An additional flux of suprathermal helium ions may also be contributed by other external sources. 相似文献
95.
M. Yu. Piotrovich N. A. Silant’ev Yu. N. Gnedin T. M. Natsvlishvili S. D. Buliga 《Astronomy Reports》2016,60(5):486-497
The magnetic-field structure in regions of stationary, planar accretion disks around active galactic nuclei where general-relativistic effects can be neglected (from 10 to 200 gravitational radii) is considered. It is assumed that the magnetic field in the outer edges of the disk, which forms in the magnetosphere of the central black hole during the creation of the relativisitic jets, corresponds to the field of a magnetic dipole perpendicular to the plane of the disk. In this case, the azimuthal field component Bφ in the disk arises due to the presence of the radial field Bρ and the azimuthal velocity component Uφ. The value of the magnetic field at the inner radius of the disk is taken to correspond to the solution of the induction equation in a diffusion approximation. Numerical solutions of the induction equation are given for a number of cases. 相似文献
96.
The mineral chemistry and crystal morphology of kimberlite pyropes from the Billyakh River placer in the northeastern Siberian craton are characterised in terms of the placer history. The pyropes bear signatures of chemical weathering (dissolution), presumably in a Middle Paleozoic laterite profile, and therefore were originally hosted by Middle Paleozoic kimberlites. The broad occurrence of placer pyropes with lateritic dissolution signatures points to the presence of Middle Paleozoic diamond-bearing kimberlites in the study area. 相似文献
97.
A. V. Pynzar’ 《Astronomy Reports》2016,60(3):332-343
The dependence of the emission measure on the dispersion measure due to the Galactic background has been derived for 120 directions in the Galaxy. This analysis has yielded the mean electron density, effective thickness of the electron layer, and the volume filling factor of the clouds of ionized gas along the line of sight. The pulsar J1745?2900, which lies in a direction close to the direction toward the center of the Galaxy, is located at least 100 pc closer to the observer than the source Sgr A* along the line of sight. The scatter-broadened angular size of J1745?2900 is determined by the turbulent medium in the Sagittarius Arm. 相似文献
98.
The formation of the penumbra of the leading spot of the active region NOAA 11117 has been studied using data fromthe Solar DynamicObservatory (SDO). HMI data on longitudinal magnetic fields, line-of-sight velocities, and continuum images were used. The appearance of localized upflows between the umbra and undisturbed photosphere precedes the penumbra formation. The sizes of them reach 1.5″–2″ and the velocity increases to 1 km/s over several minutes. These localized upflows change themselves to a region of material flowing horizontally from the penumbra (the Evershed effect). The formation of individual spine namely fine radial element of the penumbra magnetic field with higher strength and lower inclination than in the surrounding is traced for the first time. The formation of the spine manifests itself as appearance of region of 2″–3″ in size with enhanced upflow near the sunspot umbra, protrusion in longitudinal-field contours on one side of the upwelling center, and the subsequent appearance of magnetic pole of opposite polarity on the other side of the upwelling. This process is accompanied by a bending of the contour marking the boundary of the undisturbed photosphere, which puts the upwelling center in a zone of higher brightness. One possible explanation for this is the emergence of hot magnetic tube. The appearance and growth of the sunspot spines results in the formation of the penumbra. 相似文献
99.
100.
M. V. Goroshko B. F. Shevchenko V. A. Guryanov G. Z. Gil’manova 《Russian Journal of Pacific Geology》2016,10(1):13-27
The tectonics and metallogeny of the junction zone between the North Asian craton and Pacific tectonic belt are considered. This zone is characterized by a wide variety of structures superposed on the metamorphic basement, which was formed in the course of a multistage geologic development of the craton from the Precambrian to the Cenozoic. They are related to the craton evolution and its response to the collision and subduction processes in the adjacent orogenic belt, processes in the passive and active continental margins, and plume magmatism. The geological structure of the region includes blocks of metamorphic rocks of the Aldan–Stanovoi shield, Paleoproterozoic volcanogenic troughs, Mesoproterozoic–Neoproterozoic and Early Paleozoic structures of the platform cover, Late Paleozoic volcanic and terrigenous troughs, structures of the Late Mesozoic Okhotsk–Chukotka volcanic belt of the active continental margin, and Late Cretaceous riftogenic structures formed in response to plume magmatism. In total, six metallogenic epochs are recognized in the development of ore mineralization: Archean–Early Paleoproterozoic, Late Paleoproterozoic, Mesoproterozoic, Neoproterozoic, Late Paleozoic, and Late Mesozoic. The minerageny of the junction zone between the craton and Pacific belt is highly diversified, being characterized by distinct evolution in time and space. Each development stage features its own set of mineral resources. 相似文献