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Quick Response Disaster Research:Opportunities and Challenges for a New Funding Program

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International Journal of Disaster Risk Science 2020年第5期11卷 568-577页

作者： greg Oulahen Brennan Vogel Chris Gouett-Hanna Department of Geography and Environmental Studies Ryerson UniversityToronto.ON M5B 2K3.Canada Centre for Environment and Sustainability Western UniversityLondonON N6A 3K7Canada

Quick response research conducted by social scientists in the aftermath of a disaster can reveal important findings about hazards and their impacts on *** to collect perishable data,or data that will change or be lost over time,immediately following disaster has been supported for decades by two programs in the United States,amassing a collection of quick response studies and an associated research *** culture is currently being challenged to better address power imbalances between researchers and disaster-affected *** recently,Canada has not had a quick response grant *** order to survey the state of knowledge and draw from it in helping to shape the new program in Canada,this article systematically analyzes the body of research created by the two US *** results reveal a wide-ranging literature:the studies are theoretically,conceptually,topically,and methodologically quite unique to one *** diversity might appropriately reflect the nature of disasters,but the finding that many studies are not building on previous quick response research and other in sights indicate opportunities for how a new grant program in Canada can contribute to growing a robust subdiscipline of disaster research.

关键词： Canada Disaster research Hazards Quick response Social science

Fibonacci Type Semigroups

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Algebra Colloquium 2014年第4期21卷 647-652页

作者： Gerald williams Department of Mathematical Sciences University of Essex Colchester Essex C04 3SQ UK

We study “Fibonacci type” groups and semigroups. By establishing asphericity of their presentations we show that many of the groups are infinite. We combine this with Adjan graph techniques and the classification of the finite Fibonacci semigroups （in terms of the finite Fibonacci groups） to extend it to the Fibonacci type semigroups.

关键词： Fibonacci group Fibonacci semigroup cyclic presentation asphericity Adjangraph

Landmarks in the application of electrical tomography in particle science and technology

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Particuology 2010年第6期8卷 493-497页

作者： Richard A.williams Institute of Particle Science and Engineering School of ProcessEnvironmental and Materials EngineeringUniversity of LeedsLeedsWest YorkshireLS2 9JTUK

Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. The ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications. Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion.

关键词： Computational fluid dynamics Fault condition and maloperation Flow measurement Flow regime identification Particle concentration Process control Process safety

Conceptus elongation in ruminants: roles of progesterone, prostaglandin, interferon tau and cortisol

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Journal of Animal Science and Biotechnology 2015年第2期6卷 151-162页

作者： Kelsey Brooks greg Burns Thomas E Spencer Department of Animal Science and Center for Reproductive Biology Washington State University

The majority of pregnancy loss in ruminants occurs during the first three weeks after conception, particularly during the period of conceptus elongation that occurs prior to pregnancy recognition and implantation. This review integrates established and new information on the biological role of ovarian progesterone （P4）, prostaglandins （PGs）, interferon tau （IFNT） and cortisol in endometrial function and conceptus elongation. Progesterone is secreted by the ovarian corpus luteum （CL） and is the unequivocal hormone of pregnancy. Prostaglandins （PGs） and cortisol are produced by both the epithelial cells of the endometrium and the trophectoderm of the elongating conceptus. In contrast, IFNT is produced solely by the conceptus trophectoderm and is the maternal recognition of pregnancy signa that inhibits production of luteolytic pulses of PGF2α by the endometrium to maintain the CL and thus production of P4. Available results in sheep support the idea that the individual, interactive, and coordinated actions of P4, PGs, IFNT and cortisol regulate conceptus elongation and implantation by controlling expression of genes in the endometrium and/or trophectoderm. An increased knowledge of conceptus-endometrial interactions during early pregnancy in ruminants is necessary to understand and elucidate the causes of infertility and recurrent early pregnancy loss and provide new strategies to improve fertility and thus reproductive efficiency.

关键词： Conceptus Cortisol Endometrium Interferon Prostaqlandin Ruminant

Time-series prediction of shellfish farm closure: A comparison of alternatives

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Information Processing in Agriculture 2014年第1期1卷 42-50页

作者： Ashfaqur Rahman Md Sumon Shahriar Claire D’Este greg Smith John McCulloch greg Timms Autonomous Systems Program CSIRO Computational InformaticsHobartTAS 7000Australia

Shellfish farms are closed for harvest when microbial pollutants are *** pollutants are typically present in rainfall runoff from various land uses in *** currently use a number of observable parameters(river flow,rainfall,salinity)as proxies to determine when to close *** have proposed using the short term historical rainfall data as a time-series prediction problem where we aim to predict the closure of shellfish farms based only on ***-series event prediction consists of two steps:(i)feature extraction,and(ii)prediction.A number of data mining challenges exist for these scenarios:(i)which feature extraction method best captures the rainfall pattern over successive days that leads to opening or closure of the farms?,(ii)The farm closure events occur infrequently and this leads to a class imbalance problem;the question is what is the best way to deal with this problem?In this paper we have analysed and compared different combinations of balancing methods(under-sampling and over-sampling),feature extraction methods(cluster profile,curve fitting,Fourier Transform,Piecewise Aggregate Approximation,and Wavelet Transform)and learning algorithms(neural network,support vector machine,k-nearest neighbour,decision tree,and Bayesian Network)to predict closure events accurately considering the above data mining *** have identified the best combination of techniques to accurately predict shellfish farm closure from rainfall,given the above data mining challenges.

关键词： Aquaculture Shellfish farm closure Data mining Time series data

A model-based approximate λ-policy iteration approach to online evasive path planning and the video game ***-Man

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控制理论与应用（英文版） 2011年第3期9卷 391-399页

作者： greg FODERARO Vikram RAJU Silvia FERRARI Department of Mechanical Engineering and Materials Science Duke University

This paper presents a model-based approximate λ-policy iteration approach using temporal differences for optimizing paths online for a pursuit-evasion problem,where an agent must visit several target positions within a region of interest while simultaneously avoiding one or more actively pursuing *** method is relevant to applications,such as robotic path planning,mobile-sensor applications,and path *** methodology described utilizes cell decomposition to construct a decision tree and implements a temporal difference-based approximate λ-policy iteration to combine online learning with prior knowledge through modeling to achieve the objectives of minimizing the risk of being caught by an adversary and maximizing a reward associated with visiting target *** learning and frequent decision tree updates allow the algorithm to quickly adapt to unexpected movements by the adversaries or dynamic *** approach is illustrated through a modified version of the video game ***-Man,which is shown to be a benchmark example of the pursuit-evasion *** results show that the approach presented in this paper outperforms several other methods as well as most human players.

关键词： Approximate dynamic programming Reinforcement learning Path planning Pursuit evasion games

Osteopontin: a leading candidate adhesion molecule for implantation in pigs and sheep

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Journal of Animal Science and Biotechnology 2015年第2期6卷 177-190页

作者： greg A Johnson Robert C Burghardt Fuller W Bazer Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege Station Department of Animal Science Texas A&M UniversityCollege Station

Osteopontin （OPN; also known as Secreted Phosphoprotein 1, SPP1） is a secreted extra-cellular matrix （ECM） protein that binds to a variety of cell surface integrins to stimulate cell-cell and cell-ECM adhesion and communication. It is generally accepted that OPN interacts with apically expressed integrin receptors on the uterine luminal epithelium （LE） and conceptus trophectoderm to attach the conceptus to the uterus for implantation. Research conducted with pigs and sheep has significantly advanced understanding of the role（s） of OPN during implantation through exploitation of the prolonged peri-implantation period of pregnancy when elongating conceptuses are free within the uterine lumen requiring extensive paracrine signaling between conceptus and endometrium. This is followed by a protracted and incremental attachment cascade of trophectoderm to uterine LE during implantation, and development of a true epitheliochorial or synepitheliochorial placenta exhibited by pigs and sheep, respectively. In pigs, implanting conceptuses secrete estrogens which induce the synthesis and secretion of OPN in adjacent uterine LE. OPN then binds to αvβ6 integrin receptors on trophectoderm, and the αvβ3 integrin receptors on uterine LE to bridge conceptus attachment to uterine LE for implantation. In sheep, implanting conceptuses secrete interferon tau that prolongs the lifespan of CL. Progesterone released by CL then induces OPN synthesis and secretion from the endometrial GE into the uterine lumen where OPN binds integrins expressed on trophectoderm （αvβ3） and uterine LE （identity of specific integrins unknown） to adhere the conceptus to the uterus for implantation. OPN binding to the αvβ3 integrin receptor on ovine trophectoderm cells induces in vitro focal adhesion assembly, a prerequisite for adhesion and migration of trophectoderm, through activation of： 1） P70S6K via crosstalk between FRAP1/MTOR and MAPK pathways; 2） MTOR, PI3K, MAPK3/MAPK1 （Erk1/2） and MAPK14 （p38） signalin

关键词： Implantation Integrins Psteoponti Pigs Sheep

Evaluation of Summer Monsoon Clouds over the Tibetan Plateau Simulated in the ACCESS Model Using Satellite Products

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Advances in Atmospheric Sciences 2019年第3期36卷 326-338,341页

作者： Liang HU Zhian SUN Difei DENG greg ROFF State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences School of Physical Environmental and Mathematical Sciences The University of New South Wales Science to Services Australian Bureau of Meteorology Institute of Atmospheric Physics Chinese Academy of Sciences

Cloud distribution characteristics over the Tibetan Plateau in the summer monsoon period simulated by the Australian Community Climate and Earth System Simulator(ACCESS) model are evaluated using COSP [the CFMIP(Cloud Feedback Model Intercomparison Project) Observation Simulator Package]. The results show that the ACCESS model simulates less cumulus cloud at atmospheric middle levels when compared with observations from CALIPSO and CloudSat, but more ice cloud at high levels and drizzle drops at low levels. The model also has seasonal biases after the onset of the summer monsoon in May. While observations show that the prevalent high cloud at 9–10 km in spring shifts downward to 7–9 km,the modeled maximum cloud fractions move upward to 12–15 km. The reason for this model deficiency is investigated by comparing model dynamical and thermodynamical fields with those of ERA-Interim. It is found that the lifting effect of the Tibetan Plateau in the ACCESS model is stronger than in ERA-Interim, which means that the vertical velocity in the ACCESS model is stronger and more water vapor is transported to the upper levels of the atmosphere, resulting in more high-level ice clouds and less middle-level cumulus cloud over the Tibetan Plateau. The modeled radiation fields and precipitation are also evaluated against the relevant satellite observations.

关键词： Tibetan Plateau cloud fraction ACCESS model COSP

Anosov and expanding attractors

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Science China Mathematics 2020年第9期63卷 1929-1934页

作者： Robert F.williams Department of Mathematics University of Texas at AustinAustinTX 78705USA Institute for Advanced Study PrincetonNJ 08540USA

An earlier conjecture is settled with an immersion of a 2-dimensional branched *** obstructions in linear algebra and tiling theory are studied rst.

关键词： Anosov expanding attractor Cantor set ber bundle