Showing papers by "University of Wollongong published in 2010"
13 Jun 2010
TL;DR: An action graph is employed to model explicitly the dynamics of the actions and a bag of 3D points to characterize a set of salient postures that correspond to the nodes in the action graph to recognize human actions from sequences of depth maps.
Abstract: This paper presents a method to recognize human actions from sequences of depth maps. Specifically, we employ an action graph to model explicitly the dynamics of the actions and a bag of 3D points to characterize a set of salient postures that correspond to the nodes in the action graph. In addition, we propose a simple, but effective projection based sampling scheme to sample the bag of 3D points from the depth maps. Experimental results have shown that over 90% recognition accuracy were achieved by sampling only about 1% 3D points from the depth maps. Compared to the 2D silhouette based recognition, the recognition errors were halved. In addition, we demonstrate the potential of the bag of points posture model to deal with occlusions through simulation.
1,437 citations
TL;DR: Strong evidence for a positive association between FMS competency and physical activity in children and adolescents is found and more longitudinal and intervention research examining the relationship between F MS Competency and potential psychological, physiological and behavioural outcomes in children or adolescents is recommended.
Abstract: The mastery of fundamental movement skills (FMS) has been purported as contributing to children's physical, cognitive and social development and is thought to provide the foundation for an active lifestyle. Commonly developed in childhood and subsequently refined into context- and sport-specific skills, they include locomotor (e.g. running and hopping), manipulative or object control (e.g. catching and throwing) and stability (e.g. balancing and twisting) skills. The rationale for promoting the development of FMS in childhood relies on the existence of evidence on the current or future benefits associated with the acquisition of FMS proficiency. The objective of this systematic review was to examine the relationship between FMS competency and potential health benefits in children and adolescents. Benefits were defined in terms of psychological, physiological and behavioural outcomes that can impact public health. A systematic search of six electronic databases (EMBASE, OVID MEDLINE, PsycINFO, PubMed, Scopus and SportDiscus®) was conducted on 22 June 2009. Included studies were cross-sectional, longitudinal or experimental studies involving healthy children or adolescents (aged 3-18 years) that quantitatively analysed the relationship between FMS competency and potential benefits. The search identified 21 articles examining the relationship between FMS competency and eight potential benefits (i.e. global self-concept, perceived physical competence, cardio-respiratory fitness [CRF], muscular fitness, weight status, flexibility, physical activity and reduced sedentary behaviour). We found strong evidence for a positive association between FMS competency and physical activity in children and adolescents. There was also a positive relationship between FMS competency and CRF and an inverse association between FMS competency and weight status. Due to an inadequate number of studies, the relationship between FMS competency and the remaining benefits was classified as uncertain. More longitudinal and intervention research examining the relationship between FMS competency and potential psychological, physiological and behavioural outcomes in children and adolescents is recommended.
1,056 citations
TL;DR: This study affirms that pedagogically meaningful information can be extracted from LMS-generated student tracking data, and discusses how these findings are informing the development of a customizable dashboard-like reporting tool for educators that will extract and visualize real-time data on student engagement and likelihood of success.
Abstract: Earlier studies have suggested that higher education institutions could harness the predictive power of Learning Management System (LMS) data to develop reporting tools that identify at-risk students and allow for more timely pedagogical interventions. This paper confirms and extends this proposition by providing data from an international research project investigating which student online activities accurately predict academic achievement. Analysis of LMS tracking data from a Blackboard Vista-supported course identified 15 variables demonstrating a significant simple correlation with student final grade. Regression modelling generated a best-fit predictive model for this course which incorporates key variables such as total number of discussion messages posted, total number of mail messages sent, and total number of assessments completed and which explains more than 30% of the variation in student final grade. Logistic modelling demonstrated the predictive power of this model, which correctly identified 81% of students who achieved a failing grade. Moreover, network analysis of course discussion forums afforded insight into the development of the student learning community by identifying disconnected students, patterns of student-to-student communication, and instructor positioning within the network. This study affirms that pedagogically meaningful information can be extracted from LMS-generated student tracking data, and discusses how these findings are informing the development of a customizable dashboard-like reporting tool for educators that will extract and visualize real-time data on student engagement and likelihood of success.
910 citations
TL;DR: Key issues for educational researchers are identified, new ways of conceptualizing key ideas using theoretical constructs from Castells, Bourdieu and Bernstein are offered, and a case is made for how to develop the debate in order to advance understanding is made.
Abstract: The idea of the ‘digital natives’, a generation of tech-savvy young people immersed in digital technologies for which current education systems cannot cater, has gained widespread popularity on the basis of claims rather than evidence. Recent research has shown flaws in the argument that there is an identifiable generation or even a single type of highly adept technology user. For educators, the diversity revealed by these studies provides valuable insights into students’ experiences of technology inside and outside formal education. While this body of work provides a preliminary understanding, it also highlights subtleties and complexities that require further investigation. It suggests, for example, that we must go beyond simple dichotomies evident in the digital natives debate to develop a more sophisticated understanding of our students’ experiences of technology. Using a review of recent research findings as a starting point, this paper identifies some key issues for educational researchers, offers new ways of conceptualizing key ideas using theoretical constructs from Castells, Bourdieu and Bernstein, and makes a case for how we need to develop the debate in order to advance our understanding.
614 citations
TL;DR: It is shown for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes.
Abstract: Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components.
582 citations
TL;DR: Restacked MoS(2) with enlarged c lattice parameter and surface area was prepared by exfoliation and restacking process, exhibiting high reversible lithium storage capacity and superior rate capability as anode material for lithium ion batteries.
529 citations
TL;DR: In this paper, the integration of lean principles with Six Sigma methodology as a coherent approach to continuous improvement is examined, and a conceptual model for their successful integration is provided. But, although research has been undertaken on the implementation of lean within various industries, the many tools and techniques that form the “tool box”, and its integration with six Sigma (mainly through case studies and action research), there has been little written on the journey towards integration of the two approaches.
Abstract: Purpose – Although research has been undertaken on the implementation of lean within various industries, the many tools and techniques that form the “tool box”, and its integration with Six Sigma (mainly through case studies and action research), there has been little written on the journey towards the integration of the two approaches. This paper aims to examine the integration of lean principles with Six Sigma methodology as a coherent approach to continuous improvement, and provides a conceptual model for their successful integration.Design/methodology/approach – Desk research and a literature review of each separate approach is provided, followed by a view of the literature of the integrated approach.Findings – No standard framework for lean Six Sigma or its implementation exists. A systematic approach needs to be adopted, which optimises systems as a whole, focusing the right strategies in the correct places.Originality/value – This paper contributes to knowledge by providing an insight into the evol...
500 citations
TL;DR: In this paper, the authors present a control strategy for the generator-side converter with maximum power extraction, where the potential excess of power is dissipated in the dump-load resistor with the chopper control, and the dc-link voltage is maintained.
Abstract: This paper presents a novel control strategy for the operation of a direct-drive permanent-magnet synchronous-generator-based stand-alone variable-speed wind turbine. The control strategy for the generator-side converter with maximum power extraction is presented. The stand-alone control is featured with output voltage and frequency controller that is capable of handling variable load. The potential excess of power is dissipated in the dump-load resistor with the chopper control, and the dc-link voltage is maintained. Dynamic representation of dc bus and small-signal analysis are presented. Simulation results show that the controllers can extract maximum power and regulate the voltage and frequency under varying wind and load conditions. The controller shows very good dynamic and steady-state performance.
460 citations
TL;DR: A research agenda is defined to maximise the rate of learning in this difficult field of fire management, including measuring responses at a species level, building capacity to implement natural experiments, undertaking simulation modelling, and judicious application of experimental approaches.
417 citations
TL;DR: Si/graphene composite was prepared by simply mixing of commercially available nanosize Si and graphene Electrochemical tests show that the Si/glamphene composite maintains a capacity of 1168mµg −1 and an average coulombic efficiency of 93% up to 30 cycles as mentioned in this paper.
412 citations
TL;DR: Thermocells are demonstrated, in practical configurations, that harvest low-grade thermal energy using relatively inexpensive carbon multiwalled nanotube (MWNT) electrodes that provide high electrochemically accessible surface areas and fast redox-mediated electron transfer, which significantly enhances thermocell current generation capacity and overall efficiency.
Abstract: Low efficiencies and costly electrode materials have limited harvesting of thermal energy as electrical energy using thermo- electrochemical cells (or "thermocells"). We demonstrate thermocells, in practical configurations (from coin cells to cells that can be wrapped around exhaust pipes), that harvest low-grade thermal energy using relatively inexpensive carbon multiwalled nanotube (MWNT) electrodes. These electrodes provide high electrochemically accessible surface areas and fast redox-mediated electron transfer, which significantly enhances thermocell current generation capacity and overall efficiency. Thermocell efficiency is further improved by directly synthesizing MWNTs as vertical forests that reduce electrical and thermal resistance at electrode/substrate junctions. The efficiency of thermocells with MWNT electrodes is shown to be as high as 1.4% of Carnot efficiency, which is 3-fold higher than for previously demonstrated thermocells. With the cost of MWNTs decreasing, MWNT-based thermocells may become commercially viable for harvesting low-grade thermal energy.
TL;DR: Variational approximations facilitate approximate inference for the parameters in complex statistical models and provide fast, deterministic alternatives to Monte Carlo methods as discussed by the authors, however, much of the contemporary literature on variational approximation is in Computer Science rather than Statistics, and uses terminology, notation, and examples from the former field.
Abstract: Variational approximations facilitate approximate inference for the parameters in complex statistical models and provide fast, deterministic alternatives to Monte Carlo methods. However, much of the contemporary literature on variational approximations is in Computer Science rather than Statistics, and uses terminology, notation, and examples from the former field. In this article we explain variational approximation in statistical terms. In particular, we illustrate the ideas of variational approximation using examples that are familiar to statisticians.
TL;DR: A photoelectrochemical cell was designed that catalyzes the photooxidation of water using visible light as the sole energy source and a molecular catalyst synthesized from earth-abundant elements.
Abstract: A photoelectrochemical cell was designed that catalyzes the photooxidation of water using visible light as the sole energy source and a molecular catalyst, [Mn4O4L6]+ (1+, L = bis(methoxyphenyl)phosphinate), synthesized from earth-abundant elements. The essential features include a photochemical charge separation system, [RuII(bipy)2(bipy(COO)2)], adhered to titania-coated FTO conductive glass, and 1+ embedded within a proton-conducting membrane (Nafion). The complete photoanode represents a functional analogue of the water-oxidizing center of natural photosynthesis.
TL;DR: GO, an oxygenated graphene molecule, is an inexpensive precursor currently used for large-scale production of chemically converted graphene, and is illustrated that the chemical and electrical synergies between two graphene derivatives, graphene oxide (GO) and CNTs, can indeed offer an amazingly simple strategy for processing graphene/CNT nanohybrids.
Abstract: (Figure Presented) Synergistic graphenes: The chemical and electrical synergies between graphene derivatives enable a simple, cost-effective and environmentally friendly strategy for solution-phase processing of graphene oxide (GO) and carbon nanotubes (CNTs). The new nanohybrid exhibits high performance when used as electrodes for supercapacitors (see figure; ER=electrochemically reduced, CCG = chemically converted graphene). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
California Institute of Technology1, Harvard University2, National Center for Atmospheric Research3, Lawrence Berkeley National Laboratory4, Goddard Space Flight Center5, University of York6, University of Waterloo7, Texas A&M University8, Langley Research Center9, University of Wollongong10, Princeton University11, National Oceanic and Atmospheric Administration12, Max Planck Society13, Cooperative Institute for Research in Environmental Sciences14, National University of Colombia15, National Institute of Water and Atmospheric Research16
TL;DR: In this paper, the authors present a calibration of TCCON data using WMO-scale in-strumentation aboard aircraft that measured profiles over four Total Carbon Column Observing Network (TCCON) stations.
Abstract: The Total Carbon Column Observing Network (TCCON) produces precise measurements of the column av- erage dry-air mole fractions of CO2, CO, CH4, N2O and H2O at a variety of sites worldwide. These observations rely on spectroscopic parameters that are not known with suffi- cient accuracy to compute total columns that can be used in combination with in situ measurements. The TCCON must therefore be calibrated to World Meteorological Orga- nization (WMO) in situ trace gas measurement scales. We present a calibration of TCCON data using WMO-scale in- strumentation aboard aircraft that measured profiles over four TCCON stations during 2008 and 2009. These calibrations are compared with similar observations made in 2004 and 2006. The results indicate that a single, global calibration factor for each gas accurately captures the TCCON total col- umn data within error.
TL;DR: These findings show that for a broad range of risk factors, two studies of the same population with varying response rate, sampling frame and mode of questionnaire administration yielded consistent estimates of exposure-outcome relationships, however, ORs varied between the studies where they did not use identical questionnaire items.
Abstract: There is little empirical evidence regarding the generalisability of relative risk estimates from studies which have relatively low response rates or are of limited representativeness. The aim of this study was to investigate variation in exposure-outcome relationships in studies of the same population with different response rates and designs by comparing estimates from the 45 and Up Study, a population-based cohort study (self-administered postal questionnaire, response rate 18%), and the New South Wales Population Health Survey (PHS) (computer-assisted telephone interview, response rate ~60%). Logistic regression analysis of questionnaire data from 45 and Up Study participants (n = 101,812) and 2006/2007 PHS participants (n = 14,796) was used to calculate prevalence estimates and odds ratios (ORs) for comparable variables, adjusting for age, sex and remoteness. ORs were compared using Wald tests modelling each study separately, with and without sampling weights. Prevalence of some outcomes (smoking, private health insurance, diabetes, hypertension, asthma) varied between the two studies. For highly comparable questionnaire items, exposure-outcome relationship patterns were almost identical between the studies and ORs for eight of the ten relationships examined did not differ significantly. For questionnaire items that were only moderately comparable, the nature of the observed relationships did not differ materially between the two studies, although many ORs differed significantly. These findings show that for a broad range of risk factors, two studies of the same population with varying response rate, sampling frame and mode of questionnaire administration yielded consistent estimates of exposure-outcome relationships. However, ORs varied between the studies where they did not use identical questionnaire items.
TL;DR: Qualitative findings from a study that investigated Australian university staff and students' perceptions and use of current and emerging technologies both in their daily lives and in teaching and learning contexts suggest a more sophisticated understanding about the role technologies play in the lives of both students and staff is needed.
Abstract: This paper reports qualitative findings from a study that investigated Australian university staff and students' perceptions and use of current and emerging technologies both in their daily lives and in teaching and learning contexts. Forty-six first-year students and 31 teaching and support staff from three Australian universities took part in interviews and focus groups. This paper examines how students and staff reported on their use of new technologies in their daily lives, their stated reasons for using those technologies, and their beliefs about the benefits and limitations of using technologies as teaching and learning tools. The findings question assumptions that have been made about a ''digital divide'' between ''digital native'' students and their ''digital immigrant'' teachers in higher education today, suggesting we need to develop a more sophisticated understanding about the role technologies play in the lives of both students and staff. A better understanding of student and staff perspectives will allow for more informed decisions about the implementation of educational technologies in today's higher education institutions.
TL;DR: This paper surveys, classifies, and compares state-of-the-art tag reading protocols, and presents research directions for existing and future tags reading protocols.
Abstract: RFID technologies have revolutionized the asset tracking industry, with applications ranging from automated checkout to monitoring the medication intakes of elderlies. In all these applications, fast, and in some cases energy efficient, tag reading is desirable, especially with increasing tag numbers. In practice, tag reading protocols face many problems. A key one being tag collision, which occurs when multiple tags reply simultaneously to a reader. As a result, an RFID reader experiences low tag reading performance, and wastes valuable energy. Therefore, it is important that RFID application developers are aware of current tag reading protocols. To this end, this paper surveys, classifies, and compares state-of-the-art tag reading protocols. Moreover, it presents research directions for existing and future tag reading protocols.
University of Bordeaux1, Centre national de la recherche scientifique2, Simón Bolívar University3, University of Wollongong4, Metz5, Institut de radioprotection et de sûreté nucléaire6, Hampton University7, Karolinska Institutet8, European Space Research and Technology Centre9, Niels Bohr Institute10
TL;DR: An overview of the whole on-going Geant4-DNA project is presented, including its most recent developments that are available in the Geant 4 toolkit since December 2009, as well as an illustration example simulating the direct irradiation of a biological chromatin fiber.
Abstract: The Geant4-DNA project proposes to develop an open-source simulation software based and fully included in the general-purpose Geant4 Monte-Carlo simulation toolkit. The main objective of this software is to simulate biological damages induced by ionizing radiations at the cellular and sub-cellular scale. This project was originally initiated by the European Space Agency for the prediction of the deleterious effects of radiations that may affect astronauts during future long duration space exploration missions. In this paper, the Geant4-DNA collaboration presents an overview of the whole on-going project, including its most recent developments that are available in the Geant4 toolkit since December 2009 (release 9.3), as well as an illustration example simulating the direct irradiation of a biological chromatin fiber. Expected extensions involving several research domains, such as particle physics, chemistry and cellular and molecular biology, within a fully interdisciplinary activity of the Geant4 collaboration are also discussed.
TL;DR: The state of the art in lipid mass spectrometry is discussed and several areas in which current approaches are deficient and further innovation is required are highlighted.
Abstract: Recent expansion in research in the field of lipidomics has been driven by the development of new mass spectrometric tools and protocols for the identification and quantification of molecular lipids in complex matrices. Although there are similarities between the field of lipidomics and the allied field of mass spectrometry (e.g., proteomics), lipids present some unique advantages and challenges for mass spectrometric analysis. The application of electrospray ionization to crude lipid extracts without prior fractionation-the so-called shotgun approach-is one such example, as it has perhaps been more successfully applied in lipidomics than in any other discipline. Conversely, the diverse molecular structure of lipids means that collision-induced dissociation alone may be limited in providing unique descriptions of complex lipid structures, and the development of additional, complementary tools for ion activation and analysis is required to overcome these challenges. In this article, we discuss the state of the art in lipid mass spectrometry and highlight several areas in which current approaches are deficient and further innovation is required.
TL;DR: This paper showed that prefibrillar aggregates of E22G (arctic) variant of the Aβ1−42 peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity.
Abstract: Oligomeric assemblies formed from a variety of disease-associated peptides and proteins have been strongly associated with toxicity in many neurodegenerative conditions, such as Alzheimer’s disease. The precise nature of the toxic agents, however, remains still to be established. We show that prefibrillar aggregates of E22G (arctic) variant of the Aβ1−42 peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity. Moreover, we show that this phenomenon is common to other amyloid systems, such as wild-type Aβ1–42, the I59T variant of human lysozyme and an SH3 domain. These findings are consistent with a model in which the exposure of hydrophobic surfaces as a result of the aggregation of misfolded species is a crucial and common feature of these pathogenic species.
01 Jan 2010
TL;DR: It is shown that prefibrillar aggregates of E22G (arctic) variant of the Abeta(1-42) peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity.
Abstract: Oligomeric assemblies formed from a variety of disease-associated peptides and proteins have been strongly associated with toxicity in many neurodegenerative conditions, such as Alzheimer’s disease. The precise nature of the toxic agents, however, remains still to be established. We show that prefibrillar aggregates of E22G (arctic) variant of the Aβ1−42 peptide bind strongly to 1-anilinonaphthalene 8-sulfonate and that changes in this property correlate significantly with changes in its cytotoxicity. Moreover, we show that this phenomenon is common to other amyloid systems, such as wild-type Aβ1–42, the I59T variant of human lysozyme and an SH3 domain. These findings are consistent with a model in which the exposure of hydrophobic surfaces as a result of the aggregation of misfolded species is a crucial and common feature of these pathogenic species.
TL;DR: The relationship between social, business and technical dimensions and a provisional framework for making sense of social innovation are examined, which are the main driver in the development and application of new ideas to solving problems and improving social conditions.
Abstract: This article examines what we understand by the concept of social innovation. Historically, the emphasis has been on how to translate innovations in science and technology into commercial applications. Typically, company survival is explained in terms of an 'innovation imperative' in the pursuit of profits and competitive advantage. In contrast, social innovations are triggered by an interest in improving the well-being of people in society. Social rather than economic concerns are the main driver in the development and application of new ideas to solving problems and improving social conditions. We examine the relationship between social, business and technical dimensions and develop a provisional framework for making sense of social innovation.
TL;DR: This study of the effects of ocean warming and CO2 driven acidification on development and calcification of marine invertebrate larvae reared in experimental conditions from the outset of development shows the positive and negative effects of these stressors.
Abstract: Background: As the oceans simultaneously warm, acidify and increase in PCO2, prospects for marine biota are of concern. Calcifying species may find it difficult to produce their skeleton because ocean acidification decreases calcium carbonate saturation and accompanying hypercapnia suppresses metabolism. However, this may be buffered by enhanced growth and metabolism due to warming. Methodology/Principal Findings: We examined the interactive effects of near-future ocean warming and increased acidification/PCO2 on larval development in the tropical sea urchin Tripneustes gratilla. Larvae were reared in multifactorial experiments in flow-through conditions in all combinations of three temperature and three pH/PCO2 treatments. Experiments were placed in the setting of projected near future conditions for SE Australia, a global change hot spot. Increased acidity/PCO2 and decreased carbonate mineral saturation significantly reduced larval growth resulting in decreased skeletal length. Increased temperature (+3uC) stimulated growth, producing significantly bigger larvae across all pH/PCO2 treatments up to a thermal threshold (+6uC). Increased acidity (-0.3-0.5 pH units) and hypercapnia significantly reduced larval calcification. A +3uC warming diminished the negative effects of acidification and hypercapnia on larval growth. Conclusions and Significance: This study of the effects of ocean warming and CO2 driven acidification on development and calcification of marine invertebrate larvae reared in experimental conditions from the outset of development (fertilization) shows the positive and negative effects of these stressors. In simultaneous exposure to stressors the dwarfing effects of acidification were dominant. Reduction in size of sea urchin larvae in a high PCO2 ocean would likely impair their performance with negative consequent effects for benthic adult populations.
13 Apr 2010
TL;DR: Two efficient ABS constructions supporting flexible threshold predicate are proposed by exploring a new technique for signature signing and are provably secure in the random oracle model, while the second construction does not rely on therandom oracle assumption.
Abstract: In an attribute-based signature (ABS), users sign messages with any predicate of their attributes issued from an attribute authority. Under this notion, a signature attests not to the identity of the individual who signed a message, but a claim regarding the attributes the underlying signer possesses. In ABS, users cannot forge signatures with attributes they do not possess even through colluding. On the other hand, a legitimate signer remains anonymous without the fear of revocation and is indistinguishable among all the users whose attributes satisfying the predicate specified in the signature. ABS is useful in many important applications such as anonymous authentication and attribute-based messaging systems.In this paper, we propose two efficient ABS constructions supporting flexible threshold predicate by exploring a new technique for signature signing. Compared with existed schemes, the new constructions provide better efficiency in terms of both the computational cost and signature size. The first new construction is provably secure in the random oracle model, while the second construction does not rely on the random oracle assumption. To further reduce the trust on attribute authority, we also show an ABS construction with multiple attribute authorities. It is worth noting that the security of all the proposed constructions is not relying on generic group. As an illustrative application, we construct an efficient non-transferable access control system from ABS.
TL;DR: In this article, the effects of weather, terrain, fuels on fire severity were compared using remote sensing of two large fires in south-eastern Australian forests, and the probability of contrasting levels of fire severity (fire confined to the understorey vs. tree canopies consumed) was analysed using logistic regression.
Abstract: The effects of weather, terrain, fuels on fire severity were compared using remote sensing of the severity of two large fires in south-eastern Australian forests. The probability of contrasting levels of fire severity (fire confined to the understorey vs. tree canopies consumed) was analysed using logistic regression. These severities equate to extremes of fire intensity ( 10,000 kW m−1), consequent suppression potential (high vs. nil) and potential adverse ecological impacts on vertebrate fauna and soils (low vs. high). Weather was the major influence on fire severity. Crown fire was absent under non-extreme weather and but more likely under extreme weather, particularly on ridges in vegetation unburnt for >10 years. Crown fire probability was very low in recently burnt vegetation (1–5 years) and increased at higher fuel ages. In all cases, fire severity was lower in valleys, probably due to effects of wind protection and higher fuel moisture in moderating fire behaviour. Under non-extreme weather, fires are likely to be suppressible and burn heterogeneously, due to the influence of topographic position, slope and fuel load. Under extreme weather, fires are influenced only by fuel and topographic position, and probability of suppression on accessible ridges will be low except in recently burnt (i.e. 1–5 year old) fuels. Topographically imposed variation may mitigate adverse ecological effects on arboreal fauna and soil erosion potential.
TL;DR: It is shown that trapdoor indistinguishability is a sufficient condition for thwarting keyword-guessing attacks and answers the open problem of how to construct PEKS (dPEKS) schemes that are provably secure against keyword-Guessing attacks.
TL;DR: A review of the current knowledge relevant to the removal of boron by reverse osmosis (RO) and to a lesser extent by nanofiltration (NF) membranes is provided in this paper.
TL;DR: In this article, a flexible, free-standing, paper-like, graphene-silicon composite materials have been synthesized by a simple, one-step, in-situ filtration method.
TL;DR: In this article, it was shown that though different oxides experience distinct phase transition processes in the initial discharge, metallic Mn and Li(2)O are the end products of discharge, while MnO is the end product of recharge for all these oxides between 0.0 and 3.0 V vs. Li(+)/Li.