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Urban storage heat flux variability explored using satellite, meteorological and geodata
The storage heat flux (ΔQS) is the net flow of heat stored within a volume that may include the air, trees, buildings and ground. Given the difficulty of measurement of this important and large flux in urban areas, we explore the use of Earth Observation (EO) data. EO surface temperatures are used with ground-based meteorological forcing, urban morphology, land cover and land use information to estimate spatial variations of ΔQS in urban areas using the Element Surface Temperature Method (ESTM). First, we evaluate ESTM for four “simpler” surfaces. These have good agreement with observed values. ESTM coupled to SUEWS (an urban land surface model) is applied to three European cities (Basel, Heraklion, London), allowing EO data to enhance the exploration of the spatial variability in ΔQS. The impervious surfaces (paved and buildings) contribute most to ΔQS. Building wall area seems to explain variation of ΔQS most consistently. As the paved fraction increases up to 0.4, there is a clear increase in ΔQS. With a larger paved fraction, the fraction of buildings and wall area is lower which reduces the high values of ΔQS
Supercurrent transferring through c-axis cuprate Josephson junctions with thick normal-metal-bridge
With simple but exactly solvable model, we investigate the supercurrent
transferring through the c-axis cuprate superconductor-normal
metal-superconductor junctions with the clean normal metal much thicker than
its coherence length. It is shown that the supercurrent as a function of
thickness of the normal metal decreases much slower than the exponential
decaying expected by the proximity effect. The present result may account for
the giant proximity effect observed in the c-axis cuprate SNS junctions.Comment: 6 pages, 4 figure
Ciguatera Poisoning: A Global Issue with Common Management Problems
Ciguatera poisoning, a toxinological syndrome comprising an enigmatic mixture of gastrointestinal, neurocutaneous and constitutional symptoms, is a common food-borne illness related to contaminated fish consumption. As many as 50 000 cases worldwide are reported annually, and the condition is endemic in tropical and subtropical regions of the Pacific Basin, Indian Ocean and Caribbean. Isolated outbreaks occur sporadically but with increasing frequency in temperate areas such as Europe and North America. Increase in travel between temperate countries and endemic areas and importation of susceptible fish has led to its encroachment into regions of the world where ciguatera has previously been rarely encountered. In the developed world, ciguatera poses a public health threat due to delayed or missed diagnosis. Ciguatera is frequently encountered in Australia. Sporadic cases are often misdiagnosed or not medically attended to, leading to persistent or recurrent debilitating symptoms lasting months to years. Without treatment, distinctive neurologic symptoms persist, occasionally being mistaken for multiple sclerosis. Constitutional symptoms may be misdiagnosed as chronic fatigue syndrome. A common source outbreak is easier to recognize and therefore notify to public health organizations. We present a case series of four adult tourists who developed ciguatera poisoning after consuming contaminated fish in Vanuatu. All responded well to intravenous mannitol. This is in contrast to a fifth patient who developed symptoms suggestive of ciguatoxicity in the same week as the index cases but actually had staphyloccoccal endocarditis with bacteraemia. In addition to a lack of response to mannitol, clinical and laboratory indices of sepsis were present in this patient. Apart from ciguatera, acute gastroenteritis followed by neurological symptoms may be due to paralytic or neurotoxic shellfish poisoning, scombroid and pufferfish toxicity, botulism, enterovirus 71, toxidromes and bacteraemia. Clinical aspects of ciguatera toxicity, its pathophysiology, diagnostic difficulties and epidemiology are discussed
Conductance Characteristics between a Normal Metal and a Superconductor Carrying a Supercurrent
The low-temperature conductance (G) characteristics between a normal metal
and a clean superconductor (S) carrying a supercurrent parallel to the
interface is theoretically investigated. Increasing causes lowering and
broadening of (1) coherence peaks of s-wave S, and d-wave S at (100) contact,
(2) midgap-states-induced zero-bias conductance peak for d-wave S at (110)
contact, and (3) Andreev-reflection-induced enhancement of within the gap
near the metallic-contact limit. Novel features found include a current-induced
central peak and a three-humped structure at intermediate barrier strength,
etc.Comment: 4 pages, 4 figure
Calculations of polarizabilities and hyperpolarizabilities for the Be ion
The polarizabilities and hyperpolarizabilities of the Be ion in the
state and the state are determined. Calculations are performed
using two independent methods: i) variationally determined wave functions using
Hylleraas basis set expansions and ii) single electron calculations utilizing a
frozen-core Hamiltonian. The first few parameters in the long-range interaction
potential between a Be ion and a H, He, or Li atom, and the leading
parameters of the effective potential for the high- Rydberg states of
beryllium were also computed. All the values reported are the results of
calculations close to convergence. Comparisons are made with published results
where available.Comment: 18 pp; added details to Sec. I
Taking Stock: A report from the UK Teacher Education Network for sustainable development (ESD) /global citizenship (GC) - survey on provision for ESD/GC in initial teacher education in the UK
In 2009-10, the UK Teacher Education (TE) Network for Education for Sustainable Development and Global Citizenship (ESDGC) developed and implemented anemail survey to explore how teacher educators approach ESDGC in their courseprovision. The survey aimed to establish the pattern of Teacher Educationprovision for sustainable development/global citizenship across the UK in primaryand secondary so as to work with colleagues to support and develop provision in amore consistent form. It was sent to all Heads of Education in all English highereducation providers and to named contacts in Scotland, Northern Ireland andWales. It was also sent to all School - Centred Initial Teacher Training (SCITTs).By June 2010, 32 responses had been received from 27 providers. Researchers atthe Development Education Research Centre (DERC) were commissioned to workwith the Network Management Team at the Centre for Cross Curricular Initiatives(CCCI) to analyse the data and produce this report
Hall Conductivity in a Spin-Triplet Superconductor
We calculate the Hall conductivity for a spin-triplet superconductor, using a
generalized pairing symmetry dependent on an arbitrary phase, \vphi. A
promising candidate for such an order parameter is SrRuO, whose
superconducting order parameter symmetry is still subject to investigation. The
value of this phase can be determined through Kerr rotation and DC Hall
conductivity measurements. Our calculations impose significant constraints on
\vphi.Comment: 4 pages, 4 figure
A survey of cost-sensitive decision tree induction algorithms
The past decade has seen a significant interest on the problem of inducing decision trees that take account of costs of misclassification and costs of acquiring the features used for decision making. This survey identifies over 50 algorithms including approaches that are direct adaptations of accuracy based methods, use genetic algorithms, use anytime methods and utilize boosting and bagging. The survey brings together these different studies and novel approaches to cost-sensitive decision tree learning, provides a useful taxonomy, a historical timeline of how the field has developed and should provide a useful reference point for future research in this field
CSNL: A cost-sensitive non-linear decision tree algorithm
This article presents a new decision tree learning algorithm called CSNL that induces Cost-Sensitive Non-Linear decision trees. The algorithm is based on the hypothesis that nonlinear decision nodes provide a better basis than axis-parallel decision nodes and utilizes discriminant analysis to construct nonlinear decision trees that take account of costs of misclassification.
The performance of the algorithm is evaluated by applying it to seventeen datasets and the results are compared with those obtained by two well known cost-sensitive algorithms, ICET and MetaCost, which generate multiple trees to obtain some of the best results to date. The results show that CSNL performs at least as well, if not better than these algorithms, in more than twelve of the datasets and is considerably faster. The use of bagging with CSNL further enhances its performance showing the significant benefits of using nonlinear decision nodes.
The performance of the algorithm is evaluated by applying it to seventeen data sets and the results are
compared with those obtained by two well known cost-sensitive algorithms, ICET and MetaCost, which generate multiple trees to obtain some of the best results to date.
The results show that CSNL performs at least as well, if not better than these algorithms, in more than twelve of the data sets and is considerably faster.
The use of bagging with CSNL further enhances its performance showing the significant benefits of using non-linear decision nodes
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