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A simple model for reconstructing geomagnetic field intensity with (10)~Be production rate and its application in Loess studies

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Science China Earth Sciences 2008年第6期51卷 855-861页

作者： j. warren BECK NSF-AMS Laboratory University of Arizona

A simple model for reconstructing the paleomagnetic field intensity with (10)~Be production rate was used for the first time in Loess (10)~Be studies of Luochuan profile. Using the LGM (Last Glacial Maxmium) method, the climatic effects and geomagnetic modulation effects on loess (10)~Be was separated and in turn the 80 ka geomagnetic excursion sequence reconstructed, of which the globally remarkable geomagnetic excursion events such as the Laschamp (42 ka), Mono Lake (32 ka) during the Last Glacial period were revealed and the paleo-geomagnetic intensity curve from Loess (10)~Be over the past 80 ka was quantitatively reconstructed. The reconstructed paleo-intensity fits well with the paleo-intensity curves (SINT200 and NAPIS75), which indicates the significance of global criterion of the (10)~Be paleo- intensity curve and the future direction of loess (10)~Be tracing studies. Results show the irregular vari-ability of the East Asian monsoon precipitation in Loess Plateau is the main cause that has resulted in the ambiguity of the geomagnetic modulation of the (10)~Be record in the loess, and the intrinsic source component of the loess (10)~Be and inherited fraction of magnetic susceptibility (SUS) are characterized by the 'quasi-homogeneous distribution' manner.

关键词： (10)~Be LGM geomagnetic excursion paleointensity quasi-homogeneous distribution

Irradiation uniformity at the Laser Megaj.ule facility in the context of the shock ignition scheme

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High Power Laser Science and Engineering 2014年第2期2卷 1-12页

作者： Mauro Temporal Benoit Canaud warren j. Garbett Rafael Ramis Stefan Weber Centre de Math'ematiques et de Leurs Applications ENS Cachan and CNRS 61 Av. du President Wilson Cachan Cedex France CEA DIF Arpajon Cedex France AWE plc Aldermaston Reading Berkshire United Kingdom ETSI Aeron'auticos Universidad Polit'ecnica de Madrid Madrid Spain ELI-Beamlines Institute of Physics Academy of Sciences of the Czech Republic Prague Czech Republic

The use of the Laser Megaj.ule facility within the shock ignition scheme has been considered. In the first part of the study, one-dimensional hydrodynamic calculations were performed for an inertial confinement fusion capsule in the context of the shock ignition scheme providing the energy gain and an estimation of the increase of the peak power due to the reduction of the photon penetration expected during the high-intensity spike pulse. In the second part, we considered a Laser Megaj.ule configuration consisting of 176 laser beams that have been grouped providing two different irradiation schemes. In this configuration the maximum available energy and power are 1.3 Mj.and 440 TW. Optimization of the laser–capsule parameters that minimize the irradiation non-uniformity during the first few ns of the foot pulse has been performed. The calculations take into account the specific elliptical laser intensity profile provided at the Laser Megaj.ule and the expected beam uncertainties. A significant improvement of the illumination uniformity provided by the polar direct drive technique has been demonstrated. Three-dimensional hydrodynamic calculations have been performed in order to analyse the magnitude of the azimuthal component of the irradiation that is neglected in twodimensional hydrodynamic simulations.

关键词： inertial confinement fusion shock ignition laser system

SOX A Comparison With the South African Status Quo

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j.urnal of Modern Accounting and Auditing 2012年第3期8卷 357-364页

作者： warren j. Maroun University of the Witwatersrand Johannesburg South Africa

Auditor independence provisions enshrined in the Sarbanes-Oxley Act （SOX） were promulgated in 2002 in response to the Errron-Anderson scandal leading to a diminution of trust in the audit profession. In seeking to regulate auditor independence in the name of investor protection, SOX has been heralded as ＂ground-breaking＂ public interest reform. Ironically, when one considers the substance of these reforms and contrasts them with the situation prevailing in South Africa, a different impression results. Despite the fact that South Africa is classified as a ＂developing＂ nation and one which has only recently transitioned to democracy, many of the auditor independence principles legislated under SOX have been part of generally accepted practice in South Africa since the 1950s. Accordingly, SOX may not be the progressive example of auditor regulation that it is generally perceived to be.

关键词： auditor independence auditing regulations independent regulators Auditing Profession Act (2005),Sarbanes-Oxley Act (2002) South Africa United States of America

Blind spots in climate finance for innovation Peter warren

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Advances in Climate Change Research 2020年第1期11卷 60-64页

作者： Peter warren School of Public Policy University College London(UCL)LondonWCIH 9QUUK

International climate finance is a sub-set of green finance and refers to investments specifically in climate change mitigation and adaptation activities,which primarily involve public finance and the leveraging of private finance in developing *** addition to continued international support for scaling low carbon solutions and facilitating replicability in developing countries,there remains an important need to increase the amount of climate finance provided to innovation,particularly demonstration(for technology innovation)and pilot implementation(for policy innovation),and to channel a greater proportion of Official Development Assistance(ODA)to‘hard-to-abate'areas,such as industrial decarbonisation,international transport and cross-sectoral issues like cooling and behavioural insights,to accelerate the commercialisation and implementation of technological,linancial and policy solutions to contribute to meeting the Paris Agreement's goal of limiting global warming to‘well-below'2℃ in these *** research,development and demonstration(RD&D)support with technical assistance is important in providing the route to obtain wider donor finance(concessional finance)and private finance to enable deployment through scalability and replicability.

关键词： Climate finance Climate policy Paris Agreement Official development assistance Industrial decarbonisation Sustainable cooling Behavioural insights International transport

Trait plasticity, not values, best corresponds with woodland plant success in novel and manipulated habitats

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j.urnal of Plant Ecology 2013年第3期6卷 201-210页

作者： Robert j.warren II j.ffrey K.Lake Department of Biology SUNY Buffalo State1300 Elmwood AvenueBuffaloNY 14222USA Department of Biology Adrian CollegeAdrianMI49221USA

Aims The clustering of plants with similar leaf traits along environmental gradients may arise from adaptation as well as acclimation to het-erogeneous habitat *** the forces that shape plant leaf traits requires both linking variation in trait morphology with abiotic gradients and linking that trait variation with plant per-formance under varying abiotic *** the spectrum of plant types,shade-tolerant evergreen herbs are relatively low in trait plasticity,compared to deciduous and sun-adapted *** plants employ stress-tolerant strategies for survival,which coincide with relatively static trait morphologies,slow growth and hence a lower ability to adj.st to changing environmental *** We investigate how the survival of two ecologically similar under-story evergreen species,Asarum arifolium and Hepatica nobilis,cor-responds with variation in six commonly measured functional traits(leaf area,specific leaf area,plant height,leaf number,leaf length and shoot mass)along natural and experimental abiotic *** examine temporal(the period 2007-9)and spatial(100 km)variations in these traits after(i)translocating 576 plants across a span from the southerm Appalachian Mountains in NC,USA,to the Piedmont,GA,USA,which includes north-and south-facing slope habitats and(ii)the experimental manipulation of diffuse light and soil *** findings We find that when translocated into a novel habitats,with novel environmental conditions that often are more extreme than the source habitat,both species appear capable of considerable mor-phological acclimation and generally converge to similar trait *** nobilis does not exhibit mean trait values particu-larly different from those of ***,but it demonstrates much greater phenotypic *** results indicate that relatively conservative plant species nonetheless acclimate and survive across heterogeneous environmental conditions.

关键词： Functional traits Asarum arifolium Hepatica nobilis niche specific leaf area understory

Applying molecular genetic tools to tiger conservation

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Integrative Zoology 2010年第4期5卷 351-362页

作者： Shu-j.n LUO warren E.j.HNSON Stephen j.O’BRIEN School of Life Sciences Peking UniversityBeijingChina Laboratory of Genomic Diversity National Cancer InstituteFrederickMDUSA

The utility of molecular genetic approaches in conservation of endangered taxa is now commonly *** the past decade,conservation genetic analyses based on mitochondrial DNA sequencing and microsatellite genotyping have provided powerful tools to resolve taxonomy uncertainty of tiger subspecies,to define conservation units,to reconstruct phylogeography and demographic history,to examine the genetic ancestry of extinct subspecies,to assess population genetic status non-invasively,and to verify genetic background of captive tigers *** genetic status of tiger subspecies and populations and implications for developing strategies for the survival of this charismatic species both in situ and ex situ are discussed.

关键词： conservation genetics mitochondrial DNA microsatellite subspecies tiger

A review of stochastic algorithms with continuous value function approximation and some new approximate policy iteration algorithms for multidimensional continuous applications

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控制理论与应用（英文版） 2011年第3期9卷 336-352页

作者： warren B.POWELL Department of Operations Research and Financial Engineering Princeton University

We review the literature on approximate dynamic programming,with the goal of better understanding the theory behind practical algorithms for solving dynamic programs with continuous and vector-valued states and actions and complex information *** build on the literature that has addressed the well-known problem of multidimensional(and possibly continuous) states,and the extensive literature on model-free dynamic programming,which also assumes that the expectation in Bellman’s equation cannot be ***,we point out complications that arise when the actions/controls are vector-valued and possibly *** then describe some recent research by the authors on approximate policy iteration algorithms that offer convergence guarantees(with technical assumptions) for both parametric and nonparametric architectures for the value function.

关键词： Approximate dynamic programming Reinforcement learning Optimal control Approximation algorithms

Modern Optical Engineering The Design of Optical Systems 3rd ed.

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Control design of an unmanned hovercraft for agricultural applications

2000年

作者： warren j. Smith

来源：畅想之星图书光盘版（南... 评论

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International j.urnal of Agricultural and Biological Engineering 2015年第2期8卷 72-79页

作者： Deyka I Garcia warren N White Department of Mechanical Engineering Universidad Tecnológica de PanamáPanamá0819-07289Panamá Department of Mechanical and Nuclear Engineering Kansas State UniversityManhattanKS 66506USA

The efficient and precise application of agricultural materials such as fertilizer or herbicide can be greatly facilitated by autonomous *** is especially important under difficult conditions at remote *** purpose of this work is to develop an accurate nonlinear controller using a direct Lyapunov approach to ensure stability of an unmanned hovercraft prototype used for the execution of these agricultural *** a craft constitutes an underactuated system which has fewer actuators than degrees of *** proposed closed loop system is simulated to demonstrate that a control law can stabilize both the actuated and unactuated degrees of freedom of the *** is shown that the position and orientation of the hovercraft achieve high dynamic and steady performance.

关键词： controller direct Lyapunov method nonholonomic constraint underactuated system unmanned hovercraft