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Buildings and terrain unified-multidimensional dual data structure for GIS

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Geo-Spatial Information Science 2015年第4期18卷 151-158页

作者： Pawel BOGUSLAWSKI christopher GOLD Department of Architecture and the Built Environment University of the West of EnglandFrenchay Campus Coldharbour LaneBristolBS161QYUK School of Computing and Mathematics University of South WalesPontypriddUK Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduChina

3D city models are widely used in many disciplines and applications,such as urban planning,disaster management,and environmental ***,the terrain and embedded objects like buildings are taken into consideration.A consistent model integrating these elements is vital for GIS analysis,especially if the geometry is accompanied by the topological relations between neighboring *** a model allows for more efficient and errorless *** memory consumption is another crucial aspect when the wide area of a city is considered-light models are highly *** methods of the terrain representation using the geometrical-topological data structure-the dual half-edge-are proposed in this *** integration of buildings and other structures like bridges with the terrain is also presented.

关键词： multidimensional modeling GIS data structures

Is sympatric speciation in nature only possible with micro-parapatry? A new case study of glacial lake cyprinid fishes

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National Science Review 2022年第12期9卷 21-23页

作者： christopher H.Martin Department of Integrative Biology University of California Museum of Vertebrate Zoology University of California

Although numerous theoretical models of the feasibility and necessary conditions for sympatric speciation abound in the literature,clear-cut examples in nature remain ***,as always in speciation research,this statement strongly depends on your definition of sympatric speciation [1-3].If using the biogeographic definition of sympatric speciation as divergence between individuals in a population within’cruising range’of each other [4],

关键词： CLEAREST EXAMPLES GENE FLOW

Variations in Isochore Thickness of the Ecca Sediments in the Eastern Cape Province of South Africa,as Deduced from Gravity Models

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1699-1712页

作者： christopher BAIYEGUNHI Oswald GWAVAVA School of Computational Sciences Faculty of Science and AgricultureUniversity of Fort Hare

Gravity modelling was carried out along five profiles that traverse the Eastern Cape Province of South Africa in order to determine the depositional surface and isochore thickness of the Ecca *** models of the subsurface rock density reveal that the Ecca Group has a maximum vertical thickness of about 3215 ± 160 *** maximum depositional surface（elevation）above sea level for the Ecca sediments is about 500 m,whilst the depth below sea level reaches about10000 *** of the isochore thickness maps with the depositional surfaces shows that the sediments in the basement highs were subsided,deformed,eroded and deposited in the basement *** basement highs served as the source area（s） for the sediments in the basement lows,thus basement highs are characterized with thin sediment cover whilst the lows have thick sediment cover.

关键词： ediment isochore thickness depositional surface Ecca Group basement highs and lows

Signals and noise in the octavolateralis systems: What is the impact of human activities on fish sensory function?

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Integrative Zoology 2015年第1期10卷 4-14页

作者： christopher B.BRAUN Department of Psychology Hunter CollegeCity University of New YorkNew YorkNYUSA

The octavolateralis systems of fishes include the vestibular,auditory,lateral line and electrosensory *** are united by common developmental and neuro-computational features,including hair cell sensors and computations based on cross-neuron analyses of differential hair cell stimulation *** systems also all use both spectral and temporal filters to separate signals from each other and from noise,and the distributed senses(lateral line and electroreception)add spatial filters as *** all sensory systems,these sensors must provide the animal with guidance for adaptive behavior within a sensory scene composed of multiple stimuli and varying levels of ambient noise,including that created by human *** the extreme,anthropogenic activities impact the octavolateralis systems by destroying or degrading the habitats that provide ecological resources and sensory *** slightly lesser levels of effect,anthropogenic pollutants can be damaging to fish tissues,with sensory organs often the most *** exposed sensory cells of the lateral line and electrosensory systems are especially sensitive to aquatic *** still lesser levels of impact,anthropogenic activities can act as both acute and chronic stressors,activating hormonal changes that may affect behavioral and sensory ***,human activities are now a nearly ubiquitous presence in aquatic habitats,often with no obvious effects on the animals exposed to *** noise,indigenous and industrial fishing techniques,and all the ancillary noises of human civilization form a major part of the soundscape of *** fish use these new sources of information about their habitat is a new and burgeoning field of study.

关键词： audition,electrosense lateral line soundscape underwater noise

Endocasts-the direct evidence and recent advances in the study of human brain evolution

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Progress in Natural Science:Materials International 2007年第9期17卷 993-1002页

作者： christopher J.Norton 86011-4099 AZ Beijing 100044 China Flagstaff Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Laboratory of Quaternary Paleontology Northern Arizona University USA

Brain evolution is one of the most important aspects of human evolution,usually studied through *** of fossil hominid endocasts allows inferences on functional anatomy,physiology,and *** this paper,we describe the general features of endocast studies and review some of the major topics in *** are:absolute and relative brain size evolution;brain shape variation;brain asymmetry and lateralization;middle meningeal vessels and venous sinuses;application of computed tomography and virtual imaging;the history of Chinese brain endocast *** particular,this review emphasizes endocast studies on Chinese hominin fossils.

关键词： endocast human fossil brain evolution cranial capacity human evolution

Spherical Tropical Geometry:a Survey of Recent Developments

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Acta Mathematica Sinica,English Series 2018年第3期34卷 454-465页

作者： Kiumars KAVEH christopher MANON Department of Mathematics University of PittsburghPittsburghPAUSA Department of Mathematics Univcrsity of KentuckyLexingtonKYUSA

This is a survey of some recent results on spherical tropical geometry.

关键词： Tropical geometry reductive group action spherical variety Grbner theory

FINITE ELEMENT EXTERIOR CALCULUS FOR PARABOLIC EVOLUTION PROBLEMS ON RIEMANNIAN HYPERSURFACES

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Journal of Computational Mathematics 2018年第6期36卷 792-832页

作者： Michael Hoist christopher Tiee Department of Mathematics University of California San Diego La Jolla CA 92093 USA

Over the last ten years, Finite Element Exterior Calculus （FEEC） has been developed as a general framework for linear mixed variational problems, their numerical approximation by mixed methods, and their error analysis. The basic approach in FEEC, pioneered by Arnold, Falk, and Winther in two seminal articles in 2006 and 2010, interprets these problems in the setting of Hilbert complexes, leading to a more general and complete understanding. Over the last five years, the FEEC framework has been extended to a broader set of problems. One such extension, due to Hoist and Stern in 2012, was to problems with variational crimes, allowing for the analysis and numerical approximation of linear and geometric elliptic partial differential equations oil Riemannian manifolds of arbitrary spatial dimension. Their results substantially generalize the existing surface finite element approximation theory in several respects. In 2014, Gillette, Hoist, and Zhu extended FEEC in another direction, namely to parabolic and hyperbolic evolution systems by combining the FEEC framework for elliptic operators with classical approaches for parabolic and hyperbolic operators, by viewing solutions to the evolution problem as lying in Bochner spaces （spaces of Banach-space valued parametrized curves）. Related work on developing an FEEC theory for parabolic evolution problems has also been done independently by Arnold and Chen. In this article, we extend the work of Gillette-Holst- Zhu and Arnold-Chen to evolution problems on Riemannian manifolds, through tile use of framework developed by Holst and Stern for analyzing variational crimes. We establish a priori error estimates that reduce to the results from earlier work in tile flat （non-criminal） setting. Some numerical examples are also presented.

关键词： FEEC Elliptic equations Evolution equations Approximation theory Inf-supconditions A priori estimates Variational crimes Equations on manifolds

Using agent-based simulation to assess diseaseprevention measures during pandemics

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Chinese Physics B 2021年第9期30卷 643-651页

作者： Yunhe Tong christopher King Yanghui Hu Department of Engineering Mathematics University of BristolBristol BS81UBUK State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China

Despite the growing interest in macroscopic epidemiological models to deal with threats posed by pandemics such as COVID-19,little has been done regarding the assessment of disease spread in day-to-day life,especially within buildings such as supermarkets where people must obtain necessities at the risk of exposure to ***,we propose an integrated customer shopping simulator including both shopper movement and choice behavior,using a force-based and discrete choice model,*** a simple extension to the force-based model,we implement the following preventive measures currently taken by supermarkets;social distancing and one-way systems,and different customer habits,assessing them based on the average individual disease exposure and the time taken to complete shopping(shopping efficiency).Results show that maintaining social distance is an effective way to reduce exposure,but at the cost of shopping *** find that the one-way system is the optimal strategy for reducing exposure while minimizing the impact on shopping *** should also visit supermarkets less frequently,but buy more when they do,if they wish to minimize their *** hope that this work demonstrates the potential of pedestrian dynamics simulations in assessing preventative measures during pandemics,particularly if it is validated using empirical data.

关键词： pedestrian dynamics occupant exposure COVID-19 simulation study

Development of a new algorithm for implementing the edge effect offset for subsidence calculations

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International Journal of Mining Science and Technology 2018年第1期28卷 61-66页

作者： Joshua Hescock christopher Newman Zach Agioutantis Department of Mining Engineering University of Kentucky

The surface deformation prediction system(SDPS) program has been developed as an engineering tool for the calculation of subsidence deformation indices through the implementation of various prediction *** basic user-defined input parameters, SDPS can determine subsidence indices, such as mining induced displacements, strains, tilt, etc., at any elevation between the seam and the horizontal or varying surface topography.A fundamental parameter in obtaining reliable ground deformation results is the determination of the edge effect *** value assigned to the edge effect offset corresponds to a virtual offsetting of boundary lines delineating the extracted panel to allow for roof cantilevering over the mined-out *** objective of this paper is to describe the methods implemented in updating the edge effect offset algorithm within *** proven geometric equations, the newly developed algorithm provides a more robust calculation of the offset boundary of the extracted panel for simplistic as well as more complex mining *** that an extracted panel is represented by a closed polyline, the new edge offset algorithm calculates a polyline offset into the extracted panel with respect to the user defined edge effect offset *** deformations are then calculated using this adjusted panel *** Matlab program was utilized for development and testing of the new edge effect offset *** completing rigorous testing regimes, the new offset algorithm will be integrated into SDPS further increasing the speed and reliability of the program resulting in a retrospective increase in capability and flexibility.

关键词： Subsidence Coal mining Influence function Edge effect