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951.
CONFORMING     
  相似文献   
952.
The scope of manufacturing research and development (R&D) in the intermetropolitan region of Limburg, Belgium, is analyzed within the context of the spatial, organizational, and size-theoretical attributes of R&D and of the core-periphery model. In spite of its peripheral location, Limburg exhibits vivid R&D activity associated with the trickled-down manufacturing from neighboring West European industrial cores. R&D in Limburg is mostly centered in multinational/locational branch plants, but also in a few modernizing, old sector establishments engaged in high and medium-level “off the shelf” technology processes. R&D was significant in terms of spending, number of newly developed prototypes, and number of patents registered. It revealed strong sector concentration with relatively dispersed spatial patterns. R&D departments and spending disclosed a positive correlation with plant size, but showed particularly high concentration coefficients when medium-size high- and medium-level technology plants were considered.  相似文献   
953.
We present light curve solutions for the W UMa-type eclipsing binaries EP, EQ, ER, ES, and V369 Cep in the old open cluster NGC 188. Using light curve solution parameters combined with reasonable mass estimates, we determine the distance modulusV-M vof the cluster. Our aim is to examine if current uncertainties in the cluster's distance and age can be resolved. Three binaries yield distance moduli close to 10 . m 80 (±0 . m 08), two others give values around 11 . m 40(±0 . m 09). Depending on the amount of reddening, we find a weighted mean distance modulus for all five binaries between 11 . m 01 and 11 . m 05 (±0 . m 06), which lends modest support for the lower distance (1.65 kpc) and older age (10 Gyr) of the cluster.Participants in the Research Experience for Undergraduates (REU) program at Florida International University, sponsored by the National Science Foundation.  相似文献   
954.
955.
On the Antarctic plateau, a joint project of French and Italian polar programmes is nearing completion: the Concordia station will be open for winter-over operation in 2005. The high altitude and high latitude of this site, the exceptionally cold, clear and stable atmosphere, its incredible astronomical seeing, the almost indefinitely flat snow surface and the not-so-difficult access make this site the most promising on Earth for future ground-based astronomical projects in various fields, including long term photometry, infrared high sensitivity imaging and high angular resolution and high contrast imaging.  相似文献   
956.
957.
In this paper we report on further observations of the third and fourth kilohertz quasi-periodic oscillations (QPOs) in the power spectrum of the low-mass X-ray binary (LMXB) 4U 1636−53. These kilohertz QPOs are sidebands to the lower kilohertz QPO. The upper sideband has a frequency  55.5 ± 1.7 Hz  larger than that of the contemporaneously measured lower kilohertz QPO. Such a sideband has now been measured at a significance  >6σ  in the power spectra of three neutron-star LMXBs (4U 1636−53, 1728−34 and 1608−52). We also confirm the presence of a sideband at a frequency ∼55 Hz less than the frequency of the lower kilohertz QPO. The lower sideband is detected at a 3.5σ level only when the lower kilohertz QPO frequency is between 800 and 850 Hz. In that frequency interval, the sidebands are consistent with being symmetric around the lower kilohertz QPO frequency. The upper limit to the rms amplitude of the lower sideband is significantly lower than that of the upper sideband for lower kilohertz QPO frequencies >850 Hz. Symmetric sidebands are unique to 4U 1636−53. This might be explained by the fact that lower kilohertz QPO frequencies as high as 800–850 Hz are rare for 4U 1728−34 and 1608−52. Finally, we also measured a low-frequency QPO at a frequency of ∼43 Hz when the lower kilohertz QPO frequency is between 700 and 850 Hz. A similar low-frequency QPO is present in the power spectra of the other two systems for which a sideband has been observed. We briefly discuss the possibility that the sideband is caused by Lense–Thirring precession.  相似文献   
958.
Cordierite — (Mg,Fe)2Al4Si5O18 — occurs as porphyroclasts within metapelitic and metavolcanic rocks from the Kemiö-Orijärvi belt, SW Finland. After crystallisation the cordierites have been deformed at temperatures between 550–825° C and pressures of 3–5 kbar. Optical microscopy reveals the following deformation-induced microstructures: a bimodal size distribution between host, 0.3 to 4.0 mm, and recrystallised (new) grains, 0.1 to 0.5 mm; the intracrystalline defect-structures of host grains yield undulatory extinction, subgrains and some twinning. Recrystallised grains are optically strain free. Grain and subgrain boundaries are generally straight and parallel to crystallographic low-index planes. Orientation distribution diagrams for host and recrystallised grains yield similar fabric diagrams, i.e. [010] perpendicular to foliation -S-, [001] and [100] parallel to S and [001] parallel to lineation -L-. The fabric diagrams indicate that [001] (010) is the dominant slip system. Transmission electron microscopy reveals straight free dislocations, glide and climb loops, minor {130} and {110} microtwins, isolated nodal points and dislocation walls. Contrast analyses yield Burgers vector b = [001] being dominant and b = [100] subordinate. Climb loops consist of 〈c〉-dislocations that are dissociated in (001) planes, glide loops are defined by [100] [010] and [001] (100). The cordierite microstructures have been interpreted to be generated by dislocation creep. The dominant recrystallisation mechanism is thought to be subgrain rotation subsequently followed by minor grain or twin-band boundary migration.  相似文献   
959.
Although the Green Climate Fund (GCF) is widely commendable in several ways, access to the Fund has been very challenging for many African countries. Using GCF published statistics, we identify possible challenges likely to be responsible for this. First, we present an assessment of the GCF’s Readiness Support Programme with respect to how the programme’s performance may have affected achievement of African countries’ readiness outcomes. Second, a critical evaluation of the status of African GCF portfolio (pipeline and approved projects) provides a means by which to assess how well Africa’s current portfolio aligns with GCF strategic impact areas, results areas and investment priorities. We then discuss GCF access modalities and the implications of relying on International Accredited Entities (IAEs) to indirectly access the Fund. The readiness support assessment indicates that the distribution of support requests and funding approvals is nearly equal across the regions of Africa, Asia Pacific and Latin America and the Caribbean. However, when the regions are considered individually, Africa demonstrates lower approvals with respect to requests and securing funding. Results from the GCF portfolio evaluation reveal that little or no attention has been devoted to GCF critical result areas such as forests and land use or transport, where great potentials for low-carbon development transitions exist. With respect to access modalities, the IAE financing mechanism currently provides access to the Fund for the majority of projects in both the global and African GCF portfolios. The implications of these findings are extensively discussed.

Key policy insights

  • For Africa, limited readiness support and a reliance on International Accredited Entities constrains capacity building, thereby reinforcing a lack of both readiness and direct access to the GCF.

  • There are opportunities for Africa to diversify its GCF portfolios, adhere to international commitments, and address its adaptation and development needs by identifying and capitalizing on linkages between GCF funding priorities, mitigation, and adaptation.

  • There are leverage points within existing climate finance and governance systems that could catalyse a shift in Africa’s engagement with the GCF and generate positive, cascading effects on institutional strengthening, direct access accreditation and securing funding.

  相似文献   
960.
The reduction in visibility that accompanies fog events presents a hazard to human safety and navigation. However, accurate fog prediction remains elusive, with numerical methods often unable to capture the conditions of fog formation, and observational methods having high false-alarm rates in order to obtain high hit rates of prediction. In this work, 5 years of observations from the Cabauw Experimental Site for Atmospheric Research are used to further investigate how false alarms may be reduced using the statistical method for diagnosing radiation-fog events from observations developed by Menut et al. (Boundary-Layer Meteorol 150:277–297, 2014). The method is assessed for forecast lead times of 1–6 h and implementing four optimization schemes to tune the prediction for different needs, compromising between confidence and risk. Prediction scores improve significantly with decreased lead time, with the possibility of achieving a hit rate of over 90% and a false-alarm rate of just 13%. In total, a further 31 combinations of predictive variables beyond the original combination are explored (including mostly, e.g., variables related to moisture and static stability of the boundary layer). Little change to the prediction scores indicates any appropriate combination of variables that measure saturation, turbulence, and near-surface cooling can be used. The remaining false-alarm periods are manually assessed, identifying the lack of spatio–temporal information (such as the temporal evolution of the local conditions and the advective history of the airmass) as the ultimate limiting factor in the methodology’s predictive capabilities. Future observational studies are recommended that investigate the near-surface evolution of fog and the role of non-local heterogeneity on fog formation.  相似文献   
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