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121.
The development and transfer of clean energy technologies to achieve universal energy access is challenging due to the inherent complexities of the energy sector, and the energy governance and financial systems in developing economies. Innovation is an essential part of successfully addressing these difficulties. Duplicating the energy infrastructure models of developed countries will not be sufficient to meet the needs of poor consumers. To the extent that innovation can accelerate energy access, it is important to understand the specific types of innovations that are necessary and how they might be facilitated. The general features of existing international clean energy innovation systems, which are predominantly driven by the markets and emissions reduction mechanisms of developed and rapidly growing emerging economies, are reviewed and the alignment of these systems to the innovation processes required to extend energy access globally is evaluated. Drawing on the innovation policy literature, the attributes of effective international and domestic energy innovation systems that are pro-poor and the associated policy approaches are identified.  相似文献   
122.
Pulkovo astrometric observations began in the 1840s using the Repsold transit instrument in the prime vertical and Ertel vertical circle. The first observers on these instruments were W.I. Struve, 1840–1856, and Kh.I. Peters, 1842–1849. In the present work, we collected and analyzed different series of latitude variations from observations made by M.O. Nuren, B. Wanach, A.A. Ivanov, I.N. Bonsdorf, and A.Ya. Orlov. In addition, results are given of investigations of a specific behavior of the Chandler polar motion in this interval, obtained by C. Chandler, Ivanov, Kh. Kimura, Orlov, and N. Sekiguchi. The aim of this paper is to search for and analyze the earliest series of Pulkovo latitudes, in order to evaluate the possibility of their use to study the motion of the pole at the maximum available range of observations. Different methods were used to isolate and analyze the sum of Chandler and annual latitude variations. The annex provides a series of Pulkovo latitude variations for 1840–1848, which may be used to extend latitude variation back to 1840.  相似文献   
123.
We describe the design, integration, and operation of the infrared test cameras for the commissioning of the Large Binocular Telescope. The design and construction phase lasted slightly more than one year from February 2007 to April 2008 and was the result of a joint collaboration among INAF Osservatorio Astronomico di Bologna, Università di Bologna Dipartimento di Astronomia (Italy) and the Max-Planck-Institut für Astronomie (Heidelberg, Germany). Thereafter, the camera was delivered to the LBT Observatory (USA) for commissioning of the telescope active optics and, more recently, for commissioning of the first light adaptive optics.  相似文献   
124.
The Laverton region, located in the eastern Yilgarn Craton (EYC) Western Australia, is second only to the Kalgoorlie region for gold endowment. The integration of high-density, potential-field data, regional- and camp-scale seismic reflection data, regional- and mine-scale structural analysis, and geochronologically-constrained stratigraphy, provided new insights into the 4D architecture and tectonic evolution of Laverton region.  相似文献   
125.
Site assessment and monitoring data were analyzed for 26 stream restoration projects in North Carolina where the channel was reconfigured. Post-project changes in channel capacity were highly variable from site to site, but more than 60% of the projects underwent, on average at a given site, at least a 20% change in channel capacity. An analysis of site and basin geomorphology revealed that large post-construction adjustments were associated with highly dynamic stream channels characterized by a combination of high sediment transport capacity, large sediment supply, and/or easily eroded bank materials. In-stream structures along dynamic, reconfigured channels also exhibited high incidences of damage. Thus, the design and construction of channels in a state of equilibrium, which do not exhibit excessive erosion or deposition along highly dynamic rivers is currently problematic. In light of these findings, a conceptual framework based on geomorphic parameters is put forth to assess the likelihood of project success early in the design process to (1) eliminate high risk sites from consideration of channel reconfiguration and (2) improve upon the implemented management strategies that are ultimately used. It is also argued that where space permits an enhanced natural channel, adjustment approach is likely to be more effective than projects based on natural channel design.  相似文献   
126.
Journal of Geographical Systems - The widespread availability of high spatial and temporal resolution public transit data is improving the measurement and analysis of public transit-based...  相似文献   
127.
Drawing upon theory from the field of urban political ecology, we analyse a major strategic water plan for Melbourne, Australia—the Sustainable water strategy for the Central Region, published in 2006. We assess the extent to which the strategy identified and addressed ecological sustainability in terms of: cultural frames; ecological context; social equity; and engagement processes. We identify that the strategy's framing of water was largely separate from its social and ecological context. This framing resulted in the importance of issues such as environmental flows, social equity and cultural values being diminished, thus avoiding the inevitable confrontation with environmental limits needed to ensure long-term ecological sustainability. Our analysis shows that the discursive dominance of economics limited the response to persuasive scientific arguments for greater ecological consideration in the strategy. Our findings suggest that broadening engagement with the diverse ways in which water is valued is likely to contribute to more equitable and ecologically sustainable water futures.  相似文献   
128.
In this paper, the material point method (MPM) is presented as a tool for simulating large deformation, gravity-driven landslides. The primary goal is to assess the interaction of these flow-like events with the built environment. This includes an evaluation of earthen mounds when energy dissipating devices are placed in the path of a snow avalanche. The effectiveness of the embankments is characterized using displacement, velocity, mass, and energy measures. A second example quantifies the force interaction between a landslide and a square rigid column. Multiple slide approach angles are considered, and various aspects of the impact force are discussed.  相似文献   
129.
The effectiveness of larval behavior in regulating transport between well-mixed, low-inflow estuaries and coastal waters in seasonally arid climates is poorly known. We determined the flux of an assemblage of benthic crustacean larvae relative to physical conditions between a shallow estuary and coastal waters on the upwelling coast of northern California (38°18′N, 123°03′W) from 29 to 31 March 2006. We detected larval behaviors that regulate transport in adjacent coastal waters and other estuaries for only two taxa in the low-inflow estuary, but they were apparent for taxa outside the estuary. Vertical mixing in the shallow estuary may have overwhelmed larvae of some species, or salinity fluctuations may have been too slight to cue tidal vertical migrations. Nevertheless, all larval stages of species that complete development in nearshore coastal waters were present in the estuary, because they remained low in the water column reducing seaward advection or they were readily exchanged between the estuary and open coast by tidal flows. Weak tidal flows and gravitational circulation at the head of the estuary reduced seaward transport during development for species that completed development nearshore, whereas larval release during nocturnal ebb tides enhanced seaward transport for species that develop offshore. Thus, nonselective tidal processes dominated larval transport for most species back and forth between the low-inflow estuary and open coastal waters, whereas in adjacent open coastal waters, larval behavior in the presence of wind-induced shear was more important in regulating migrations between adult and larval habitats along this upwelling coast.  相似文献   
130.
The Silver Creek caldera (southern Black Mountains, western Arizona) is the source of the 18.8 Ma, >700 km3 Peach Spring Tuff (PST) supereruption, the largest eruption generated in the Colorado River Extensional Corridor (CREC) of the southwestern United States. Within and immediately surrounding the caldera is a sequence of volcanics and intrusions ranging in age from ~19 to 17 Ma. These units offer a record of magmatic processes prior to, during, and immediately following the PST eruption. To investigate the thermal evolution of the magmatic center that produced the PST, we applied a combination of Ti-in-zircon thermometry, zircon saturation thermometry, and high-precision U–Pb CA–TIMS zircon dating to representative pre- and post-supereruption volcanic and intrusive units from the caldera and its environs. Similar to intracaldera PST zircons, zircons from a pre-PST trachytic lava (19 Ma) and a post-PST caldera intrusion (18.8 Ma) yield exceptionally high-Ti concentrations (most >20 ppm, some up to nearly 60 ppm), corresponding to calculated temperatures that exceed 900 °C. In these units, Ti-in-zircon temperatures typically surpass zircon saturation temperatures (ZSTs), suggesting the entrainment of zircon that had grown in hotter environments within the magmatic system. Titanium concentrations in younger volcanic and intrusive units (~18.7–17.5 Ma) decline through time, corresponding to an average cooling rate of 10?3.5 °C/year. The ~200 k.y. thermal peak evident at Silver Creek caldera is spatially limited: elsewhere in the Miocene record of the northern CREC, Ti-in-zircon concentrations and ZSTs are much lower, suggesting that felsic magmas were generally substantially cooler.  相似文献   
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