19,528 research outputs found
A systematic review of empirical methods for modelling sectoral carbon emissions in China
© 2019 Elsevier Ltd A number of empirical methods have been developed to study China's sectoral carbon emissions (CSCE). Measuring these emissions is important for climate change mitigation. While several articles have reviewed specific methods, few attempts conduct a systematic analysis of all the major research methods. In total 807 papers were published on CSCE research between 1997 and 2017. The primary source of literature for this analysis was taken from the Web of Science database. Based on a bibliometric analysis using knowledge mapping with the software CiteSpace, the review identified five common families of methods: 1) environmentally-extended input-output analysis (EE-IOA), 2) index decomposition analysis (IDA), 3) econometrics, 4) carbon emission control efficiency evaluation and 5) simulation. The research revealed the main trends in each family of methods and has visualized this research into ten research clusters. In addition, the paper provides a direct comparison of all methods. The research results can help scholars quickly identify and compare different methods for addressing specific research questions
Positive Semidefiniteness and Positive Definiteness of a Linear Parametric Interval Matrix
We consider a symmetric matrix, the entries of which depend linearly on some
parameters. The domains of the parameters are compact real intervals. We
investigate the problem of checking whether for each (or some) setting of the
parameters, the matrix is positive definite (or positive semidefinite). We
state a characterization in the form of equivalent conditions, and also propose
some computationally cheap sufficient\,/\,necessary conditions. Our results
extend the classical results on positive (semi-)definiteness of interval
matrices. They may be useful for checking convexity or non-convexity in global
optimization methods based on branch and bound framework and using interval
techniques
Doping dependent evolution of magnetism and superconductivity in Eu1-xKxFe2As2 (x = 0-1) and temperature dependence of lower critical field Hc1
We have synthesized the polycrystalline samples of Eu1-xKxFe2As2 (x = 0-1)
and carried out systematic characterization using x-ray diffraction, ac & dc
magnetic susceptibility, and electrical resistivity measurements. We have seen
a clear signature of the coexistence of superconducting transition (Tc = 5.5 K)
with SDW ordering in our under doped sample viz. x = 0.15. The spin density
wave transition observed in EuFe2As2 get completely suppressed at x = 0.3 and
superconductivity arises below 20 K. Superconducting transition temperature Tc
increases with increase in K content and a maximum Tc = 33 K is reached for x =
0.5, beyond which it decreases again. The doping dependent T(x) phase diagram
is extracted from the magnetic and electrical transport data. It is found that
magnetic ordering of Eu-moments coexists with superconductivity up to x = 0.6.
The isothermal magnetization data taken at 2 K for the doped samples suggest 2+
valence states of Eu ions. We also present the temperature dependence of the
lower critical field Hc1 of superconducting polycrystalline samples. The value
of Hc1(0) obtained for x = 0.3, 0.5, and 0.7 after taking the demagnetization
factor into account is 248, 385, and 250 Oe, respectively. The London
penetration depth {\lambda}(T) calculated from the lower critical field does
not show exponential behaviour at low temperature, as would be expected for a
fully gapped clean s-wave superconductor. In contrast, it shows a T2 power-law
feature down to T = 0.4 Tc, as observed in Ba1-xKxFe2As2 and BaFe2-xCoxAs2.Comment: 17 pages, 10 figure
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The ‘common sense’ memory belief system and its implications
Memory experts, the police, and the public, completed a memory questionnaire containing a series of statements about autobiographical memory. The statements covered issues such as the nature of memory, determinants of accuracy, the relation of emotion and trauma to memory, and respondents indicated their agreement/disagreement with each of the statements. The police and public were found to share a ‘common sense’ memory belief system (CSMBS) in which memories were like videos/photographs, and accuracy was determined by the number of details recalled and also by their vividness. In direct contrast the scientific memory belief system, held by memory researchers, largely based on scientific evidence, was the opposite of the CSMBS and memories were judged to be fragmentary, number of details and their nature did not predict accuracy, and memories and their details could be in error and even false. The problematic nature of the CSBMS, which is pervasive in society, in raising the probability of flawed judgments of memory evidence is considered and, by way of illustration, applied to the (very high) attrition rate in complaints of rape
Golden Rectangle Treemap
© Published under licence by IOP Publishing Ltd. Treemaps, a visualization method of representing hierarchical data sets, are becoming more and more popular for its efficient and compact displays. Several algorithms have been proposed to create more useful display by controlling the aspect ratios of the rectangles that make up a treemap. In this paper, we introduce a new treemap algorithm, generating layout in which the rectangles are easier to select and hierarchy information is easier to obtain. This algorithm generates rectangles which approximate golden rectangles. To prove the effectiveness of our algorithm, at the end of this paper several analyses on golden rectangle treemap have been done on disk file system
Searching for biosignatures by their rotational spectrum: global fit and methyl group internal rotation features of dimethylsulphoxide up to 116 GHz
The identification and quantification of molecules in interstellar space and atmospheres of planets in the solar systems and in exoplanets rely on spectroscopicmethods and laboratory work is essential to provide the community with the spectral features needed to analyse cosmological observations. Rotational spectroscopy in particular, with its intrinsic high resolution,
allows the unambiguous identification of biomolecular building blocks and biosignature gases which can be correlated with the origin of life or the identification of habitable planets.We report the extension of the measured rotational transition frequencies of dimethylsulphoxide and its 34S and 13C isotopologues in the millimetrewave range (59.6–78.4
GHz) by use of an absorption spectrometer based on the supersonic expansion technique. Hyperfine patterns related to the methyl group internal rotation were analysed in the microwave range region (6–18 GHz) with a Pulsed Jet Fourier Transform spectrometer at extremely high resolution (2 kHz) and reliable predictions up to 116 GHz are provided.
The focus on sulphur-bearing molecules is motivated by the fact that sulphur is largely involved in the intra- and
inter-molecular hydrogen bonds in proteins and although it is the 10th most abundant element in the known Universe, understanding its chemistry is still amatter of debate.Moreover, sulphur-bearingmolecules, in particular dimethylsulphoxide, have been indicated as possible biosignature gases to be monitored in the search of habitable exoplanets
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