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81.
Geoffrey I. Webb Janice R. Boughton Fei Zheng Kai Ming Ting Houssam Salem 《Machine Learning》2012,86(2):233-272
Averaged n-Dependence Estimators (AnDE) is an approach to probabilistic classification learning that learns by extrapolation from marginal to full-multivariate
probability distributions. It utilizes a single parameter that transforms the approach between a low-variance high-bias learner
(Naive Bayes) and a high-variance low-bias learner with Bayes optimal asymptotic error. It extends the underlying strategy
of Averaged One-Dependence Estimators (AODE), which relaxes the Naive Bayes independence assumption while retaining many of
Naive Bayes’ desirable computational and theoretical properties. AnDE further relaxes the independence assumption by generalizing AODE to higher-levels of dependence. Extensive experimental
evaluation shows that the bias-variance trade-off for Averaged 2-Dependence Estimators results in strong predictive accuracy
over a wide range of data sets. It has training time linear with respect to the number of examples, learns in a single pass
through the training data, supports incremental learning, handles directly missing values, and is robust in the face of noise.
Beyond the practical utility of its lower-dimensional variants, AnDE is of interest in that it demonstrates that it is possible to create low-bias high-variance generative learners and suggests
strategies for developing even more powerful classifiers. 相似文献
82.
Victoria Aragon Stephanie Gauthier Peter Warren Patrick A. B. James Ben Anderson 《Building Research & Information》2019,47(4):375-393
ABSTRACTOccupancy patterns are necessary to estimate energy demand and evaluate thermal comfort in households. Because of this, many European countries are developing representative domestic schedules to replace outdated criteria. This paper evaluates the state of knowledge of UK domestic occupancy patterns and develops new domestic occupancy profiles for England. The presented research (1) characterizes methods for collecting occupancy data and inferring patterns; (2) identifies and assesses the quality of categories of occupancy patterns used in building simulation; and (3) develops updated occupancy profiles. A systematic scoping review identified social and monitoring surveys as the most deployed data-collection methods. A systematic literature review also established that the occupancy categories most frequently used in UK building simulation are (a) a family with dependent children where the parents work full time; and (b) a retired elderly couple who spend most of their time indoors. The interview sample from the English Housing Survey 2014–15 was used to map household typologies. Results show that categories (a) and (b) combined amount to only 19% of England’s households, which suggest models are over-reliant on these groups. Considering this result, the paper develops occupancy patterns for England derived from 2015 UK Time Use Survey diaries for each household typology previously identified. 相似文献
83.
Single‐walled carbon nanotubes (SWCNTs) dispersed in N‐methylpyrrolidone (NMP) were functionalized by addition of polystyryl radicals from 2,2,6,6‐tetramethyl‐1‐piperidinyloxy‐ended polystyrene (SWCNT‐g‐PS). The amount of polystyrene grafted to the nanotubes was in the range 20‐25 wt% irrespective of polystyrene number‐average molecular weight ranging from 2270 to 49 500 g mol?1. In Raman spectra the ratios of D‐band to G‐band intensity were similar for all of the polystyrene‐grafted samples and for the starting SWCNTs. Numerous near‐infrared electronic transitions of the SWCNTs were retained after polymer grafting. Transmission electron microscopy images showed bundles of SWCNT‐g‐PS of various diameters with some of the polystyrene clumped on the bundle surfaces. Composites of SWCNT‐g‐PS in a commercial‐grade polystyrene were prepared by precipitation of mixtures of the components from NMP into water, i.e. the coagulation method of preparation. Electrical conductivities of the composites were about 10?15 S cm?1 and showed no percolation threshold with increasing SWCNT content. The glass transition temperature (Tg) of the composites increased at low filler loadings and remained constant with further nanotube addition irrespective of the length and number of grafted polystyrene chains. The change of heat capacity (ΔCp) at Tg decreased with increasing amount of SWCNT‐g‐PS of 2850 g mol?1, but ΔCp changed very little with the amount of SWCNT‐g‐PS of higher molecular weight. The expected monotonic decrease in ΔCp coupled with the plateau behavior of Tg suggests there is a limit to the amount that Tg of the matrix polymer can increase with increasing amount of nanotube filler. Copyright © 2012 Society of Chemical Industry 相似文献
84.
ARMA models provide a parsimonious and flexible mechanism for modeling the evolution of a time series. Some useful measures of these models (e.g., the autocorrelation function or the spectral density function) are tedious to compute by hand. This paper uses a computer algebra system, not simulation, to calculate measures of interest associated with ARMA models. 相似文献
85.
While emergency response actions are known to range from conventional to improvised, less is known about the thinking processes that underlie these actions. This paper presents a statistical analysis of cognition and behaviour reported by police personnel who responded to two significant US disasters: the 1995 bombing of the Murrah Building in Oklahoma City and the 2001 attack on the World Trade Center in New York City. The results suggest the prominence of conventional behaviour coupled with cognitive processes closely tied to recognition, and of improvised behaviours that are linked to more explicit reasoning processes. The results underscore the value of exploring cognitive foundations of both conventional and improvised behaviours to enrich understanding of human response to disaster. 相似文献
86.
M. Mehendale B. Bosacchi E. Gatzogiannis A. Dogariu W. S. Warren M. O. Scully 《Journal of Modern Optics》2013,60(16-18):2645-2653
Abstract We present experimental evidence of a resonant coherent anti-Stokes Raman spectroscopy (CARS) signal from dipicolinic acid, a marker molecule in anthrax spores. We also show some evidence of resonant CARS signal associated with the 1000 cm?1 resonance from Bacillus Globigii spores which are similar to anthrax spores. These results constitute a first step towards developing a rapid identification technique for bacterial spores. 相似文献
87.
The remote West Australian town of Broome has a unique photography heritage that sheds new light on the complexities of photography and intercultural relations. During the early twentieth century thriving Japanese communities were established in this region around the lucrative pearling industry. These Japanese communities also helped to develop a fascinating photography culture in Broome. Photography was not simply a business opportunity for the Japanese or a means of documenting people and events; it was a medium through which hierarchised social relations were produced, redefined, and challenged. This article examines photographs by these Japanese residents as an important site of cross-cultural communication and interpretation. These photographs of Anglo-Australian, Japanese, and Aboriginal residents of Broome enrich the study of cross-cultural photographic encounters, and emphasise the dynamic and dispersed qualities of Australian photographic practice and history. Here national histories of photography are usefully conceptualised as the products of imbricated social, economic, and cultural relations that operate across regional, national, and international realms. 相似文献
88.
Condensed tannins derived from Pinus radiata bark have been esterified and added to biodegradable plastics as extrusion compounded functional plastic additives. The presence of longer alkyl chain hexanoate esters promoted tannin miscibility in the commercial polyesters Bionolle? and Biopol? whereas short chain acetate esters tended to remain as discrete domains, acting as fillers in the processed plastics. In the aliphatic polyester Bionolle the presence of tannin esters at typical plastic additive loadings did not alter plastic mechanical properties whereas at 5% content in Biopol the tannin‐additives reduced both flexural and tensile properties. Similarly tannin esters do not alter the melt or glass transition temperatures of the polyesters, but tannin hexanoate at 5% can influence the crystallization temperatures. Artificially aging plastics realized the functionality these plant extracts can impart to plastics in acting to reduce ultraviolet (UV)‐induced plastic degradation. Results indicate the tannin‐additives likely provide a stabilising role through inhibiting UV penetration into the plastic, with color analysis suggesting the tannin moiety itself was sacrificial and preferentially degrading. The imparted UV stability was linked to the dissolution of tannin esters in the plastic with longer chain esters providing greater protection against UV degradation. Tannin esters showed potential as functional additives for biodegradable polymers enhancing the UV stability of the plastic. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41626. 相似文献
89.
Shelley Burgin Cesidio Parissi Tony Webb 《The International journal of environmental studies》2013,70(2):154-166
Sport is important internationally; but in Australia, it is part of the national identity. The enjoyment of public open space for sport is, therefore, an assumed community right. We interviewed key staff from inner Sydney councils about management issues associated with public open space. The greatest concern was sporting fields – formal and informal – which were considered to have exceeded carrying capacity mainly because of the unintended outcomes of government programmes/policies spanning; (1) ‘healthy lifestyles’ which increased public open space use; (2) ‘urban consolidation’ increased inner-city population density with associated increased usage and loss of open space; (3) ‘temporal water restriction’ during drought (not ‘water budgets’) which intensify management issues; and (4) ‘building the education revolution’, meaning that public open space lost from schools results in increased pressure on public open space. Consequences have increased human pressure on public open space without commensurate consideration for the management and/or expansion of these areas. 相似文献
90.
Synthesis and Biopharmaceutical Evaluation of Imatinib Analogues Featuring Unusual Structural Motifs 下载免费PDF全文
Prof. Kyriacos C. Nicolaou Dr. Dionisios Vourloumis Dr. Sotirios Totokotsopoulos Dr. Athanasios Papakyriakou Dr. Holger Karsunky Hanan Fernando Dr. Julia Gavrilyuk Dr. Damien Webb Dr. Antonia F. Stepan 《ChemMedChem》2016,11(1):31-37
A convenient synthesis of imatinib, a potent inhibitor of ABL1 kinase and widely prescribed drug for the treatment of a variety of leukemias, was devised and applied to the construction of a series of novel imatinib analogues featuring a number of non‐aromatic structural motifs in place of the parent molecule's phenyl moiety. These analogues were subsequently evaluated for their biopharmaceutical properties (e.g., ABL1 kinase inhibitory activity, cytotoxicity). The bicyclo[1.1.1]pentane‐ and cubane‐containing analogues were found to possess higher themodynamic solubility, whereas cubane‐ and cyclohexyl‐containing analogues exhibited the highest inhibitory activity against ABL1 kinase and the most potent cytotoxicity values against cancer cell lines K562 and SUP‐B15. Molecular modeling was employed to rationalize the weak activity of the compounds against ABL1 kinase, and it is likely that the observed cytotoxicity of these agents arises through off‐target effects. 相似文献