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新西兰教育质量保障体系(Tony davies)

2006年

作者： by Colin davies.

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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学园(学者的精神家园) 2008年第1期 77-82页

作者： Tony davies 张建华新西兰教育部云南省昆明市第五中学

质量是高等教育生存的生命线,质量保障早已成为当今高等教育界的主流话题。本文系统阐述了新西兰高等教育质量保障体系的经验,重点阐述了现行的新西兰高等教育质量保障体系及新质量保障体系的特点和原则。这对我国高等教育评估事业的发... 详细信息

质量是高等教育生存的生命线,质量保障早已成为当今高等教育界的主流话题。本文系统阐述了新西兰高等教育质量保障体系的经验,重点阐述了现行的新西兰高等教育质量保障体系及新质量保障体系的特点和原则。这对我国高等教育评估事业的发展具有一定的参考意义。

关键词：新西兰外部质量保障自评

Minimising the spread of residence-time distribution for flat and heaped powders in a wedge-shaped planar hopper

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Particuology 2017年第1期15卷 102-110页

作者： Luke Fullard Clive davies Institute of Fundamental Sciences Massey University Palmerston North Campus Private Bag 11222 Palmerston North 4442 New Zealand School of Engineering and Advanced Technology Massey University Polmerston North Campus Private Bag 11222 Palmerston North 4442 New Zealand

A wedge-shaped planar mass-flow hopper system was modelled using stress-field theory as found in the literature, The authors present governing equations for stress and velocity fields under a radial- flow assumption in a converging hopper. The velocity in the silo above the hopper is modelled as plug flow, Two set-ups are modelled, one where powder layers in the hopper are assumed to be flat, and the second in which the layers are heaped at some characteristic angle, The ejection times and residence-time distributions are calculated and presented for a range of heap angles. For realistic heap angles, the spread of the residence-time distribution decreases with increasing heap angle; in one case, the spread is halved to a well-defined limit. At this limit （the critical heap angle） the geometry of the hopper can be optimised to minimise the spread of the residence-time distribution, and hence to minimise predicted mixing in the system. We present examples of curves for a variety of parameters that minimise the predicted mixing in the hopper-silo system.

关键词： Residence-time distribution Radial stress field Hopper Heaped layers Granular

Emerging and Innovative Materials for Hydropower Engineering Applications:Turbines,Bearings,Sealing,Dams and Waterways,and Ocean Power

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Engineering 2022年第1期8卷 148-158页

作者： Emanuele Quaranta Peter davies European Commission Joint Research Centre Ispra 21027Italy Marine Structures Laboratory IFREMER Centre BretagnePlouzané29280France

The hydropower sector is currently experiencing several technological *** technologies and practices are emerging to make hydropower more flexible and more *** materials have also been recently developed to increase performance,durability,and reliability;however,no systematic discussions can be found in the ***,in this paper,novel materials for hydropower applications are presented,and their performance,advantages,and limitations are *** example,composites can reduce the weight of steel equipment by 50%to 80%,polymers and superhydrophobic materials can reduce head losses by 4%to 20%,and novel bearing materials can reduce bearing wear by 6%.These improvements determine higher efficiencies,longer life span,waste reduction,and maintenance needs,although the initial cost of some materials is not yet competitive with respect to the costs of traditional *** novel materials are described here based on the following categories:novel materials for turbines,dams and waterways,bearings,seals,and ocean hydropower.

关键词： Bearing Composite Dam Hydropower Material Ocean Seal Turbine

Understanding the pathophysiology of postpartum psychosis: Challenges and new approaches

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World Journal of Psychiatry 2017年第2期7卷 77-88页

作者： William davies Medical Research Council Centre for Neuro-psychiatric Genetics and Genomics and Division of Psychological Medicine and Clinical Neurosciences School of Medicine Cardiff University School of Psychology Cardiff University Neuroscience and Mental Health Research Institute Cardiff University

Postpartum psychosis is a severe psychiatric condition which affects 1-2 of every 1000 mothers shortly after childbirth. Whilst there is convincing evidence that the condition is precipitated by a complex combination of biological and environmental factors, as yet the pathophysiological mechanisms remain extremely poorly defined. Here, I critically review approaches that have been, or are being, employed to identify and characterise such mechanisms; I also review a recent animal model approach, and describe a novel biological risk model that it suggests. Clarification of biological risk mechanisms underlying disorder risk should permit the identification of relevant predictive biomarkers which will ensure that "at risk" subjects receive prompt clinical intervention if required.

关键词： CCN3 Immune system Steroid sulfatase Nephroblastoma-overexpressed Mouse Animal model Risk factor

Higgs boson searches at the Tevatron

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Frontiers of physics 2013年第3期8卷 270-284页

作者： Gavin J. davies Imperial College London London SW7 2AZ United Kingdom

This article reviews the Higgs searches at the Tevatron, as presented over the summer of 2012; both standard model （SM） and beyond the standard model （BSM） results are discussed as detailed （arXiv： 1207.0449; Phys. Rev. Lett., 2012, 109： 071804; Phys. Rev. D, 2012, 85： 032005）. We discuss the combination of searches by the CDF and DO Collaborations for the standard model Higgs boson in the mass range 100-200 GeV/c2 produced in the the gg →H, WH, ZH, tfH, and vector boson fusion production modes, and decaying in the H → bb, H → W＋W-, H → ZZ, H →π＋π-, and H →γγ modes. The data, collected at the Fermilab Tevatron collider in p/5 collisions at √s = 1.96 TeV, correspond to integrated luminosities of up to 10 fb^-1. In the absence of signal, we expect to exclude the regions 100 〈 mH 〈 120 GeV/c2 and 139 〈 mH 〈 184 GeV/c2. We exclude, at the 95% C.L., two regions： 100 〈 mH 〈 103 GeV/c2, and 147 〈 mH 〈 180 GeV/c2. We observe a significant excess of events in the mass range between 115 and 140 GeV/c2. The local significance corresponds to 3.0 standard deviations at mH = 120 GeV/ce; the global significance （incorporating the lookelsewhere effect） for such an excess anywhere in the full mass range investigated is approximately 2.5 standard deviations. Furthermore, we separately combine searches for H→ bb-, H → W＋W- and H →γγ. We find that the excess is concentrated in the H →bb channel, appearing in the searches over a broad range of raN; the maximum local significance of 3.3 standard deviations corresponds to a global significance of approximately 3.1 standard deviations. The observed signal strengths in all channels are consistent with the expectation for a standard model Higgs boson at mH = 125 GeV/c2. The production of neutral Higgs bosons in association with b-quarks can be significantly enhanced in various beyond the standard model scenarios, including Supersymmetry. The recent combination of such searches from the two collaborations is discussed.

关键词： Higgs Tevatron

Applications of cnoidal and snoidal wave solutions via optimal system of subalgebras for a generalized extended (2+1)-D quantum Zakharov-Kuznetsov equation with power-law nonlinearity in oceanography and ocean engineering

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Journal of Ocean Engineering and Science 2024年第2期9卷 126-153页

作者： Oke davies adeyemo International Institute for Symmetry Analysis and Mathematical Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusPrivate Bag X 2046Mmabatho 2735Republic of South Africa

The nonlinear evolution equations have a wide range of applications,more precisely in physics,biology,chemistry and engineering *** domain serves as a point of interest to a large extent in the world’s mathematical ***,this paper purveys an analytical study of a generalized extended(2+1)-dimensional quantum Zakharov-Kuznetsov equation with power-law nonlinearity in oceanography and ocean *** Lie group theory of differential equations is utilized to compute an optimal system of one dimension for the Lie algebra of the *** further reduce the equation using the subalgebras ***,more general solutions of the underlying equation are secured for some special cases of n with the use of extended Jacobi function expansion ***,we secure new bounded and unbounded solutions of interest for the equation in various solitonic structures including bright,dark,periodic(cnoidal and snoidal),compact-type as well as singular *** applications of cnoidal and snoidal waves of the model in oceanography and ocean engineering for the first time,are outlined with suitable *** can be of interest to oceanographers and ocean engineers for future ***,to visualize the dynamics of the results found,we present the graphic display of each of the ***,we construct conservation laws of the understudy equation via the application of Noether’s theorem.

关键词： A generalized extended(2+1)-dimensional quantum Zakharov-Kuznetsov equation Lie point symmetries Optimal system of subalgebras Cnoidal and snoidal waves Extended Jacobi function expansion technique Conservation laws

Soliton solutions,travelling wave solutions and conserved quantities for a three-dimensional soliton equation in plasma physics

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Communications in Theoretical Physics 2021年第12期73卷 25-57页

作者： Chaudry Masood Khalique Oke davies adeyemo International Institute for Symmetry Analysis and Mathematical Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusPrivate Bag X 2046Mmabatho 2735South Africa

Many physical systems can be successfully modelled using equations that admit the soliton *** addition,equations with soliton solutions have a significant mathematical *** this paper,we study and analyze a three-dimensional soliton equation,which has applications in plasma physics and other nonlinear sciences such as fluid mechanics,atomic physics,biophysics,nonlinear optics,classical and quantum fields ***,solitons and solitary waves have been observed in numerous situations and often dominate long-time *** perform symmetry reductions of the equation via the use of Lie group theory and then obtain analytic solutions through this technique for the very first *** integration of the resulting ordinary differential equation is done which gives new analytic travelling wave solutions that consist of rational function,elliptic functions,elementary trigonometric and hyperbolic functions solutions of the ***,various solitonic solutions are secured with the use of a polynomial complete discriminant system and elementary integral *** solutions comprise dark soliton,doubly-periodic soliton,trigonometric soliton,explosive/blowup and singular *** further exhibit the dynamics of the solutions with pictorial representations and discuss *** conclusion,we contemplate conserved quantities for the equation under study via the standard multiplier approach in conjunction with the homotopy integral *** state here categorically and emphatically that all results found in this study as far as we know have not been earlier obtained and so are new.

关键词： three-dimensional soliton equation Lie group theory conserved quantities soliton and exact travelling wave solutions physics

Large-Scale Weather Systems: A Future Research Priority

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Advances in Atmospheric Sciences 2006年第6期23卷 832-841页

作者： Huw C.davies Institute for Atmospheric and Climate Science ETHZurichSwitzerland

A brief assessment is provided of both the case against and the case for assigning priority to research on large-scale weather systems （LSWS）. The three-fold case against is based upon： the emergence of new overarching themes in environmental science; the fresh emphasis upon other sub-disciplines of the atmospheric science; and the mature state of research and prediction of LSWS. The case for is also supported by three arguments. First is the assertion that LSWS research should not merely be an integral but a major component of future research related to both the new overarching themes and the other sub-disciplines. Second recent major developments in LSWS research, as epitomized by the paradigm shifts in the prediction strategy for LSWS and the emergence of the potential vorticity perspective, testify to the theme＇s on-going vibrancy. Third the field＇s future development, as exemplified by the new international THORPEX （The Observing System Research and Predictability Experiment） programme, embodies a perceptive dovetailing of intellectually challenging fundamental research with directed application（s） of societal and economic benefit. It is thus inferred that LSWS research, far from being in demise, will feature at the forefront of the new relationship between science and society.

关键词： research priorities atmospheric dynamics weather systems THORPEX

A case for mantle plumes

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Chinese Science Bulletin 2005年第15期50卷 1541-1554页

作者： Geoffrey F. davies Research School of Earth Sciences Australian National University Canberra ACT 0200 Australia

The existence of at least several plumes in the Earth’s mantle can be inferred with few assumptions from well-established observations. As well, thermal mantle plumes can be predicted from well-established and quanti-fied fluid dynamics and a plausible assumption about the Earth’s early thermal state. Some additional important ob-servations, especially of flood basalts and rift-related mag-matism, have been shown to be plausibly consistent with the physical theory. Recent claims to have detected plumes using seismic tomography may comprise the most direct evidence for plumes, but plume tails are likely to be difficult to resolve definitively and the claims need to be well tested. Although significant questions remain about its viability, the plume hypothesis thus seems to be well worth continued investiga-tion. Nevertheless there are many non-plate-related mag-matic phenomena whose association with plumes is unclear or unlikely. Compositional buoyancy has recently been shown potentially to substantially complicate the dynamics of plumes, and this may lead to explanations for a wider range of phenomena, including “headless” hotspot tracks, than purely thermal plumes.

关键词：地球覆盖物羽毛流体动力学热量对流火山