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201.
In this paper, we compare different policy incentives for overcoming investment uncertainties that are typical for low-carbon technologies prior to their commercialisation, some of which may be attributable to market failures. The paper focuses on the particular case of carbon capture and storage (CCS) technologies and conducts a qualitative multi-criteria analysis of different public policy support schemes for CCS demonstration to evaluate their suitability. The assessed schemes include mandatory CCS, emission performance standards and several different financial incentives (in addition to the European Union Emission Trading Scheme). Based on the available literature and on experience in the UK and Germany with promotion instruments for low-carbon technologies, the results of our analysis suggest that two alternative schemes, a CCS bonus incentive or a carbon dioxide (CO2) price guarantee, perform best in comparison with the other assessed instruments. While they reduce the uncertainty of CCS investments in the face of low European Union Allowance prices, they also avoid significant adverse impacts on operational and investment decisions in electricity markets. 相似文献
202.
J. Jiménez-Vicente C. Porcel M.L. Sánchez-Saavedra E. Battaner 《Astrophysics and Space Science》1997,253(2):225-235
We propose new parameters to describe the geometry of a warped disc when viewed edge-on, a global warp parameter w, and a
family of three parameters A, B and C that describe, independently, the shape of the warp. These parameters are useful to
detect some key effects in the understanding of warps. We have also developed software (WIG) which is able to calculate these
parameters for a given image of a galaxy in any wavelength and which is described here with some examples, namely ESO 235–53
in the optical, NGC 4013 in 21 cm and NGC 4565 in 1.2 mm continuum.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
203.
FIRST RESULTS FROM VIRGO,THE EXPERIMENT FOR HELIOSEISMOLOGY AND SOLAR IRRADIANCE MONITORING ON SOHO 总被引:1,自引:0,他引:1
Fröhlich Claus Andersen Bo N. Appourchaux Thierry Berthomieu Gabrielle Crommelynck Dominique A. Domingo Vicente Fichot Alain Finsterle Wolfgang Gómez Maria F. Gough Douglas Jiménez Antonio Leifsen Torben Lombaerts Marc Pap Judit M. Provost Janine Roca Cortés Teodoro Romero José Roth Hansjörg Sekii Takashi Telljohann Udo Toutain Thierry Wehrli Christoph 《Solar physics》1997,170(1):1-25
First results from the VIRGO experiment (Variability of solar IRradiance and Gravity Oscillations) on the ESA/NASA Mission SOHO (Solar and Heliospheric Observatory) are reported. The observations started mid-January 1996 for the radiometers and sunphotometers and near the end of March for the luminosity oscillation imager. The performance of all the instruments is very good, and the time series of the first 4–6 months are evaluated in terms of solar irradiance variability, solar background noise characteristics and p-mode oscillations. The solar irradiance is modulated by the passage of active regions across the disk, but not all of the modulation is straightforwardly explained in terms of sunspot flux blocking and facular enhancement. Helioseismic inversions of the observed p-mode frequencies are more-or-less in agreement with the latest standard solar models. The comparison of VIRGO results with earlier ones shows evidence that magnetic activity plays a significant role in the dynamics of the oscillations beyond its modulation of the resonant frequencies. Moreover, by comparing the amplitudes of different components ofp -mode multiplets, each of which are influenced differently by spatial inhomogeneity, we have found that activity enhances excitation. 相似文献
204.
The use of an Optec SSP/Lynxx (tradename) CCD imaging photometer for the recording of the Galilean satellite phenomena, with software supplied by Mallama (1992) is described. An example data set (for lo) and least squares reduction is presented. 相似文献
205.
206.
R.A. GarcÍa T. Corbard W.J. Chaplin S. Couvidat A. Eff-Darwich S.J. Jiménez-Reyes S.G. Korzennik J. Ballot P. Boumier E. Fossat C.J. Henney R. Howe M. Lazrek J. Lochard P.L. Pallé S. Turck-Chièze 《Solar physics》2004,220(2):269-285
In the modern era of helioseismology we have a wealth of high-quality data available, e.g., more than 6 years of data collected
by the various instruments on board the SOHO mission, and an even more extensive ground-based set of observations covering
a full solar cycle. Thanks to this effort a detailed picture of the internal rotation of the Sun has been constructed. In
this paper we present some of the actions that should be done to improve our knowledge of the inner rotation profile discussed
during the workshop organized at Saclay on June 2003 on this topic. In particular we will concentrate on the extraction of
the rotational frequency splittings of low- and medium-degree modes and their influence on the rotation of deeper layers.
Furthermore, for the first time a full set of individual |m|-component rotational splittings is computed for modes ℓ≤4 and 1<ν<2 mHz, opening new studies on the latitudinal dependence
of the rotation rate in the radiative interior. It will also be shown that these splittings have the footprints of the differential
rotation of the convective zone which can be extremely useful to study the differential rotation of other stars where only
these low-degree modes will be available. 相似文献
207.
Blanksma Derrick Hazzard Jim Damjanac Branko Lam Tom Kasani Hossein A. 《Journal of Seismology》2022,26(5):987-1002
Journal of Seismology - In this study, fault rupture and its effect on the deformation of the off-fault fractures are numerically simulated. The purpose of the analysis is to determine the distance... 相似文献
208.
Cindy Quik Ype van der Velde Tom Harkema Hans van der Plicht Jim Quik Roy van Beek Jakob Wallinga 《地球表面变化过程与地形》2021,46(13):2607-2631
There is a growing interest in the rescue and reuse of data from past studies (so-called legacy data). Data loss is alarming, especially where natural archives are under threat, such as peat deposits. Here we develop a workflow for reuse of legacy radiocarbon dates in peatland studies, including a rigorous quality assessment that can be tailored to specific research questions and study regions. A penalty is assigned to each date based on criteria that consider taphonomic quality (i.e., sample provenance) and dating quality (i.e., sample material and method used). The weights of quality criteria may be adjusted based on the research focus, and resulting confidence levels may be used in further analyses to ensure robustness of conclusions. We apply the proposed approach to a case study of a (former) peat landscape in the Netherlands, aiming to reconstruct the timing of peat initiation spatially. Our search yielded 313 radiocarbon dates from the 1950s to 2019. Based on the quality assessment, the dates—of highly diverse quality—were assigned to four confidence levels. Results indicate that peat initiation for the study area first peaked in the Late Glacial (~14,000 cal years BP), dropped during the Boreal (~9,500 cal years BP) and showed a second peak in the Subboreal (~4,500 cal years BP). We tentatively conclude that the earliest peak was mostly driven by climate (Bølling–Allerød interstadial), whereas the second was probably the result of Holocene sea level rise and related groundwater level rise in combination with climatic conditions (hypsithermal). Our study highlights the potential of legacy data for palaeogeographic reconstructions, as it is cost-efficient and provides access to information no longer available in the field. However, data retrieval may be challenging, and reuse of data requires that basic information on location, elevation, stratigraphy, sample and laboratory analysis are documented irrespective of the original research aims. 相似文献
209.
This Commentary introduces a Special Issue of Earth Surface Processes and Landforms dedicated to the memory of Stephen Coleman (1966–2012) who sadly passed away on July 23, 2012. Stephen was an incredible enthusiast for the study of bedforms and made seminal contributions to our knowledge and understanding of flow, sediment transport and bedform dynamics. Stephen presented a keynote address at MARID 3, which has led to this Special Issue (see Coleman SE, Nikora VI. 2011. Fluvial dunes: initiation, characterization, flow structure. Earth Surface Processes and Landforms 36 : 39–57. DOI. 10.1002/esp.2096) and was always keen to discuss research, from theory to techniques to experiments. He was always generous with his time and touched many with the influence of his thoughts and intellect. Our community has lost an outstanding scientist and Stephen will be greatly missed by us all. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
210.
The Imaging Magnetograph eXperiment (IMaX) for?the?Sunrise Balloon-Borne Solar Observatory 总被引:1,自引:0,他引:1
V. Mart��nez?Pillet J. C. del Toro Iniesta A. ��lvarez-Herrero V. Domingo J. A. Bonet L. Gonz��lez?Fern��ndez A. L��pez?Jim��nez C. Pastor J. L. Gasent?Blesa P. Mellado J. Piqueras B. Aparicio M. Balaguer E. Ballesteros T. Belenguer L. R. Bellot?Rubio T. Berkefeld M. Collados W. Deutsch A. Feller F. Girela B. Grauf R. L. Heredero M. Herranz J. M. Jer��nimo H. Laguna R. Meller M. Men��ndez R. Morales D. Orozco?Su��rez G. Ramos M. Reina J. L. Ramos P. Rodr��guez A. S��nchez N. Uribe-Patarroyo P. Barthol A. Gandorfer M. Knoelker W. Schmidt S. K. Solanki S. Vargas?Dom��nguez 《Solar physics》2011,268(1):57-102
The Imaging Magnetograph eXperiment (IMaX) is a spectropolarimeter built by four institutions in Spain that flew on board the Sunrise balloon-borne solar observatory in June 2009 for almost six days over the Arctic Circle. As a polarimeter, IMaX uses fast polarization modulation (based on the use of two liquid crystal retarders), real-time image accumulation, and dual-beam polarimetry to reach polarization sensitivities of 0.1%. As a spectrograph, the instrument uses a LiNbO3 etalon in double pass and a narrow band pre-filter to achieve a spectral resolution of 85 mÅ. IMaX uses the high-Zeeman-sensitive line of Fe i at 5250.2 Å and observes all four Stokes parameters at various points inside the spectral line. This allows vector magnetograms, Dopplergrams, and intensity frames to be produced that, after reconstruction, reach spatial resolutions in the 0.15??C?0.18 arcsec range over a 50×50 arcsec field of view. Time cadences vary between 10 and 33 s, although the shortest one only includes longitudinal polarimetry. The spectral line is sampled in various ways depending on the applied observing mode, from just two points inside the line to 11 of them. All observing modes include one extra wavelength point in the nearby continuum. Gauss equivalent sensitivities are 4 G for longitudinal fields and 80 G for transverse fields per wavelength sample. The line-of-sight velocities are estimated with statistical errors of the order of 5??C?40 m?s?1. The design, calibration, and integration phases of the instrument, together with the implemented data reduction scheme, are described in some detail. 相似文献