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81.
David L. McCollum Volker Krey Keywan Riahi Peter Kolp Arnulf Grubler Marek Makowski Nebojsa Nakicenovic 《Climatic change》2013,119(2):479-494
This paper assesses three key energy sustainability objectives: energy security improvement, climate change mitigation, and the reduction of air pollution and its human health impacts. We explain how the common practice of narrowly focusing on singular issues ignores potentially enormous synergies, highlighting the need for a paradigm shift toward more holistic policy approaches. Our analysis of a large ensemble of alternate energy-climate futures, developed using MESSAGE, an integrated assessment model, shows that stringent climate change policy offers a strategic entry point along the path to energy sustainability in several dimensions. Concerted decarbonization efforts can lead to improved air quality, thereby reducing energy-related health impacts worldwide: upwards of 2–32 million fewer disability-adjusted life years in 2030, depending on the aggressiveness of the air pollution policies foreseen in the baseline. At the same time, low-carbon technologies and energy-efficiency improvements can help to further the energy security goals of individual countries and regions by promoting a more dependable, resilient, and diversified energy portfolio. The cost savings of these climate policy synergies are potentially enormous: $100–600 billion annually by 2030 in reduced pollution control and energy security expenditures (0.1–0.7 % of GDP). Novel aspects of this paper include an explicit quantification of the health-related co-benefits of present and future air pollution control policies; an analysis of how future constraints on regional trade could influence energy security; a detailed assessment of energy expenditures showing where financing needs to flow in order to achieve the multiple energy sustainability objectives; and a quantification of the relationships between different fulfillment levels for energy security and air pollution goals and the probability of reaching the 2 °C climate target. 相似文献
82.
83.
Nonstandard theories of fundamental interactions typically predict the existence of new kinds of weakly interacting particles.
These can escape freely from stellar interiors and act as additional source of cooling. Considerable agreement of a variety
of astrophysical observations with standard physics can serve as a source of constraints on non-standard ideas. In this paper
we consider G117-B15A pulsating white dwarf for which the secular rate, at which the period of its fundamental mode increases,
has been accurately measured. This star has been claimed the most stable oscillator ever recorded in the optical band. Because
an additional channel of energy loss would speedup the cooling rate, one is able to use this stability to derive a bound on
axion mass and on theories with large extra dimensions. We also point to the possibility of using similar arguments to constrain
supersymmetric paticles.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
M. Siarkowski J. Sylwester G. Bromboszcs V. V. Korneev S. L. Mandelshtam S. N. Oparin A. M. Urnov I. A. Zhitnik 《Solar physics》1982,81(1):63-68
In part III of the paper containing the analysis of the INTERCOSMOS 16 ADP spectra, it is shown that by assuming the existence of a small admixture (1%) of non-thermal electrons in the active-region plasma it is possible to improve the agreement between measured and calculated fluxes for some spectra. The analysis follows the suggestion contained in the paper by Karev et al. (1980). 相似文献
85.
Pavel Mayer Marek Wolf P. G. Niarchos K. D. Gazeas V. N. Manimanis Drahomír Chochol 《Astrophysics and Space Science》2006,304(1-4):39-41
New precise times of minimum light for several early-type eclipsing binaries were obtained at three observatories. The changes of period of the following measured binaries are discussed: V1182 Aql, LY Aur, SZ Cam, FZ CMa, QZ Car, LZ Cen, V606 Cen, AH Cep and TU~Mus. 相似文献
86.
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89.
For perfectly aligned heliostats and coelostats tracking at the solar rate and half the solar rate, respectively, the solar beam has no translational motion. But, particularly in the field at eclipses, it is not possible to align heliostats and coelostats with infinite precision. We derive the effect of small misalignments on the translational motion of the beam, and give tables to allow the calculation of the accuracy to which the instruments must be mounted and adjusted to attain a desired accuracy over a given duration. Further, we show how to derive the necessary adjustments to improve alignment, given measurements of the tracking error. 相似文献
90.