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Journal of Computational Mathematics 2008年第1期26卷 76-97页

作者： Igor Boglaev matthew Hardy Institute of Fundamental Sciences Massey UniversityPrivate Bag 11-222Palmerston NorthNew Zealand Mathematical Sciences Institute Australian National UniversityCanberraAustralia 0200

This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite difference scheme for the partial differential equation, we construct a monotone domain decomposition algorithm based on a Schwarz alternating method and a box-domain decomposition. This algorithm needs only to solve linear discrete systems at each iterative step and converges monotonically to the exact solution of the nonlinear discrete problem. domain decomposition algorithm is estimated The rate of convergence of the monotone Numerical experiments are presented.

关键词： Parabolic reaction-diffusion problem Boundary layers O-method Monotone domain decomposition algorithm Uniform convergence

Signaling events during initiation of arbuscular mycorrhizal symbiosis

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Journal of Integrative Plant Biology 2014年第3期56卷 250-261页

作者： Alexa M.Schmitz Maria J.harrison Boyce Thompson Institute for Plant Research Plant Pathology and Plant-Microbe Biology Cornell University

Under nutrient-limiting conditions, plants will enter into symbiosis with arbuscular mycorrhizal （AM） fungi for the enhancement of mineral nutrient acquisition from the surrounding soil. AM fungi live in close, intracellular association with plant roots where they transfer phosphate and nitrogen to the plant in exchange for carbon. They are obligate fungi, relying on their host as their only carbon source. Much has been discovered in the last decade concerning the signaling events during initiation of the AM symbiosis, including the identification of signaling molecules generated by both partners. This signaling occurs through symbiosis-specific gene products in the host plant, which are indispensable for normal AM development. At the same time, plants have adapted complex mechanisms for avoiding infection by pathogenic fungi, including an innate immune response to general microbial molecules, such as chitin present in fungal cell walls. How it is that AM fungal colonization is maintained without eliciting a defensive response from the host is still uncertain. In this review, we present a summary of the molecular signals and their elicited responses during initiation of the AM symbiosis, including plant immune responses and their suppression.

关键词： Arbuscular mycorrhizal fungi chitin chitooligosaccharide cutin LysM MAMP-triggered immunity Myc-LCO Nod factor strigolactones symbiosis

Glial kon/NG2 gene network for central nervous system repair

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Neural Regeneration Research 2017年第1期12卷 31-34页

作者： Maria Losada-Perez Neale harrison Alicia Hidalgo School of Biosciences University of BirminghamBirminghamEnglandUK Universidad Autonoma de Madrid MadridSpain

The glial regenerative response to central nervous system（CNS） injury,although limited,can be harnessed to promote regeneration and *** provokes the proliferation of ensheathing glial cells,which can differentiate to remyelinate axons,and partially restore *** response is evolutionarily conserved,strongly implying an underlying genetic *** mammals,it is elicited by NG2 glia,but most often newly generated cells fail to *** an important goal had been to find out how to promote glial differentiation following the proliferative response.A gene network involving Notch and prospero（pros） controls the balance between glial proliferation and differentiation in flies and mice,and promotes CNS repair at least in fruit-flies.A key missing link had been how to relate the function of NG2 to this gene *** findings by Losada-Perez et al.,published in JCB,demonstrated that the Drosophila NG2 homologue kon-tiki（kon） is functionally linked to Notch and pros in *** engaging in two feedback loops with Notch and Pros,in response to injury,Kon can regulate both glial cell number and glial shape homeostasis,essential for *** offers powerful genetics to unravel the control of stem and progenitor cells for regeneration and repair.

关键词： NG2 kon-tiki glia Drosophila injury regeneration repair CNS

Asymptotically efficient parameter estimation for ordinary differential equations

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Science China Mathematics 2017年第11期60卷 2263-2286页

作者： PANG TianXiao YAN PeiSi ZHOU harrison H. School of Mathematical Sciences Zhejiang University Center for Computing and Visualization Brown University Department of Statistics and Data Science Yale University

Parameter estimation for ordinary differential equations arises in many fields of science and engineering. To be the best of our knowledge, traditional methods are often either computationally intensive or inaccurate for statistical inference. Ramsay et al.(2007) proposed a generalized profiling procedure. It is easily implementable and has been demonstrated to have encouraging numerical performance. However, little is known about statistical properties of this procedure. In this paper, we provide a theoretical justification of the generalized profiling procedure. Under some regularity conditions, the procedure is shown to be consistent for a broad range of tuning parameters. When the tuning parameters are sufficiently large, the procedure can be further shown to be asymptotically normal and efficient.

关键词： asymptotic efficiency consistency generalized profiling procedure ordinary differential equations splines

Transfer Strategy for Power Output Estimation of Wind Farm at Planning Stage Based on a SVR Model

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1460-1471页

作者： Zihao Li Wei Sun Yue Xiang Gareth P.harrison the School of Engineering University of EdinburghEdinburghEH93DWUK College of Electrical Engineering Sichuan UniversityChengdu 610065China

The conventional wind farm(WF)power generation modelling method highly relies on wind hindcast produced by record time-series data or numerical weather ***,estimating production at future sites is challenging in the absence of local wind *** address this,a data-driven WF modelling and model transfer strategy is proposed in this *** considers the challenge of how to transpose metered data from existing operational WFs to sites that might feature as a prospective site for a new *** modelling 14 WFs distributed across Scotland using a machine learning(ML)approach,this study proved it was possible to effectively model metered production at a site using modelled wind speed and *** addition,this study also found when the latitude difference between two WFs is less than 0.2 degrees and the distance is less than 5o km,two WFs in non-mountainous areas can share an ML *** results of the shared ML model remain superior to the results of the given power curve from manufacturers,after adjusting the results by the ratio of the power curve in these two *** WF model transfer strategy investigated in this work offered a novel approach to transposing WF production estimates to new sites and appeared to offer better value than simple power curves,which is of importance at the early planning stage for site selection,although it would likely not fully replace detailed micro-siting modelling which are well established in the *** Terms-Machine learning,model transfer strategy,power curve,power output estimation,wind farm.

关键词： Machine learning model transfer strategy power curve power output estimation wind farm.

A review of the formulation and application of the spatial equilibrium models to analyze policy

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Journal of Forestry Research 2011年第4期22卷 671-679页

作者： Phan Sy Hieu Steve harrison The Centre for Informatics and Statistics Ministry of Agriculture and Rural Development in Vietnam No. 2 Ngoc Ha Street Ba Dinh district Hanoi Vietnam Associate Professor the School of Economics the University of Queensland Australia.

This paper reviews alternative market equilibrium models for policy analysis. The origin of spatial equilibrium models and their application to wood and wood-processing industries are described. Three mathematical programming models commonly applied to solve spatial problems - namely linear programming, non-linear programming and mixed complementary programming - are reviewed in terms of forms of objective functions and constraint equalities and inequalities. These programming are illustrated with numerical examples. Linear programming is only applied in transportation problems to solve quantities trans, ported between regions when quantities supplied and demanded in each region are already known. It is argued that linear programming can be applied in broader context to transportation problems where supply and demand quantities are unknown and are linear. In this context, linear programming is seen as a more convenient method for modelers because it has a simpler objective function and does not require as strict conditions, for instance the equal numbers of variables and equations required in mixed complementary programming. Finally, some critical insights are provided on the interpretation of optimal solutions generated by solving spatial equilibrium models.

关键词： simplex method reduced-gradient linear programming non-linear programming mixed complementary programming

Schreibersite on the early Earth:Scenarios for prebiotic phosphorylation

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Geoscience Frontiers 2017年第2期8卷 329-335页

作者： matthew A.Pasek School of Ceoscience University of South FloridaTampaFL 33620USA

The mineral schreibersite,（Fe,Ni）_3P,provides a reactive source of phosphorus capable of forming phosphorylated *** molecules may have been an important component of prebiotic chemistry,allowing their build-up and eventual commencement of *** here are potential geochemical routes to providing schreibersite,as a potentially important prebiotic mineral,to the Hadean *** routes are identified：delivery of phosphides by meteoritic material and the reduction of phosphates to phosphides by high-temperature,low-redox *** 1-10% of all crustal phosphorus is estimated to have been in schreibersite during the Hadean,making the long-term reaction of this mineral with organic-laden water plausible for many ***,such conditions would have been conducive to the formation of life as we know it today.

关键词： Phosphorus Hadean Meteorites Thermodynamics Origin of life Prebiotic chemistry

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巨石阵建成之谜

环球科学 2024年第16期 64-67页

作者：马修·西蒙兹不详

大约4500年前,一群人聚集在如今英格兰西南部威尔特郡的一处墓地里。四周环绕的圆形土堆内,是再往前数400年就已经火化并安葬了的遗骨。但这群人聚在这里并不是为了举行葬礼。相反,他们准备开展一项工程,把这里改造成一个建筑奇迹。如今... 详细信息

大约4500年前,一群人聚集在如今英格兰西南部威尔特郡的一处墓地里。四周环绕的圆形土堆内,是再往前数400年就已经火化并安葬了的遗骨。但这群人聚在这里并不是为了举行葬礼。相反,他们准备开展一项工程,把这里改造成一个建筑奇迹。如今,他们的作品成了英国最著名且最神秘的遗迹——巨石阵。不过遗憾的是,由于这项工程开始于英国出现文字之前,他们建造巨石阵的动机无从知晓,部分建造技术也因此失传。

关键词：巨石阵建筑奇迹英格兰英国建造

Acoustic Velocities and Elastic Properties of Pyrite (FeS2) to 9.6 GPa

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Journal of Earth Science 2010年第5期21卷 792-800页

作者： matthew L Whitaker Mineral Physics Institute Stony Brook University Geodynamics Research Center Ehime University

Ultrasonic interferometry was utilized in conjunction with synchrotron-based X-ray diffraction and X-radiographic imaging to determine the compressional and shear wave velocities and unlt-cdl volumes of pyrite （FeS2） at room temperature and pressures up to 9.6 GPa. Fitting all of the experimental volume and velocity data to third-order finite-strain equations yielded the adiabatic zero-pressure bulk and shear moduli and their first pressure derivatives： Ks0=138.9（7） GPa, Go=U2.3（3） GPa, （δKS0/δP）T=KS0＇=6.0（1）, （δG0/δP）T=G0＇=3.0（〈1）, where the numbers in parentheses represent the 1δ uncertainty in the last significant digit. These results are in good agreement with several previous static compression studies on this material but differ quite strongly from the results obtained via first principles calculations. This study presents the first direct measurement of the bulk shear properties of this material.

关键词： mineral physics ultrasonic interferometry high pressure iron sulfide elastic property equation of state.

Parametric computational study on butterfly-shaped hysteretic dampers

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1214-1226页

作者： Alireza FARZAMPOUR matthew Roy EATHERTON Department of Civil and Environmental Engineering Virginia TechBlacksburgVA 24060USA

A parametric computational study is conducted to investigate the shear yielding, flexural yielding, and lateral torsional buckling limit states for butterfly-shaped links. After validating the accuracy of the finite element modeling approach against previous experiments, 112 computational models with different geometrical properties were constructed and analyzed including consideration of initial imperfections. The resulting yielding moment, corresponding critical shear force, the accumulation of plastic strains through the length of links as well as the amount of energy dissipated are investigated. The results indicate that as the shape of the butterfly-shaped links become too straight or conversely too narrow in the middle, peak accumulated plastic strains increase. The significant effect of plate thickness on the buckling limit state is examined in this study. Results show that overstrength for these links (peak force divided by yield force) is between 1.2 and 4.5, with straight links producing larger overstrength. Additionally, proportioning the links to delay buckling, and designing the links to yield in the flexural mode are shown to improve energy dissipation.

关键词： structural fuse hystcretic damper finite element analysis energy dissipation initial imperfection butterfly-shaped links