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Exact Computation of the Topology and Geometric Invariants of the Voronoi Diagram of Spheres in 3D

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Journal of Computer Science & Technology 2013年第2期28卷 255-266页

作者： Franois anton Darka Mioc Marcelo Santos Research Division of Geodesy National Space Institute Technical University of Denmark Department of Geodesy and Geomatics Engineering University of New Brunswick

In this paper, we are addressing the exact the Voronoi diagram of spheres using Wu＇s algorithm. computation of the Delaunay graph （or quasi-triangulation） and Our main contributions are first a methodology for automated derivation of invariants of the Delaunay empty circumsphere predicate for spheres and the Voronoi vertex of four spheres, then the application of this methodology to get all geometrical invariants that intervene in this problem and the exact computation of the Delaunay graph and the Voronoi diagram of spheres. To the best of our knowledge, there does not exist a comprehensive treatment of the exact computation with geometrical invariants of the Delaunay graph and the Voronoi diagram of spheres. Starting from the system of equations defining the zero-dimensional algebraic set of the problem, we are applying Wu＇s algorithm to transform the initial system into an equivalent Wu characteristic （triangular） set. In the corresponding system of algebraic equations, in each polynomial （except the first one）, the variable with higher order from the preceding polynomial has been eliminated （by pseudo-remainder computations） and the last polynomial we obtain is a polynomial of a single variable. By regrouping all the formal coefficients for each monomial in each polynomial, we get polynomials that are invariants for the given problem. We rewrite the original system by replacing the invariant polynomials by new formal coefficients. We repeat the process until all the algebraic relationships （syzygies） between the invariants have been found by applying Wu＇s algorithm on the invariants. Finally, we present an incremental algorithm for the construction of Voronoi diagrams and Delaunay graphs of spheres in 3D and its application to Geodesy.

关键词： Voronoi diagram of spheres Delaunay graph of spheres Wu's method invariant characteristic set

Phase preservation of orbital angular momentum of light in multiple scattering environment

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Light(Science & Applications) 2024年第10期13卷 2263-2275页

作者： Igor Meglinski Ivan Lopushenko anton Sdobnov Alexander Bykov College of Engineering and Physical Sciences Aston UniversityBirmingham B47ETUK Optoelectronics and Measurement Techniques University of OuluOulu FI-90014Finland

Recent advancements in wavefront shaping techniques have facilitated the study of complex structured light’s propagation with orbital angular momentum(OAM)within various *** introduction of spiral phase modulation to the Laguerre–Gaussian(LG)beam during its paraxial propagation is facilitated by the negative gradient of the medium’s refractive index change over time,leading to a notable increase in the rate of phase twist,effectively observed as phase retardation of the *** approach attains remarkable sensitivity to even the slightest variations in the medium’s refractive index(∼10−6).The phase memory of OAM is revealed as the ability of twisted light to preserve the initial helical phase even propagating through the turbid tissue-like multiple scattering *** results confirm fascinating opportunities for exploiting OAM light in biomedical applications,*** as non-invasive trans-cutaneous glucose diagnosis and optical communication through biological tissues and other optically dense media.

关键词： scattering momentum light

Lessons learnt from a deep excavation for future application of the observational method

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 468-485页

作者： Raul Fuentes anton Pillai Pedro Ferreira School of Civil Engineering University of LeedsLeedsLS2 9JTUK Ove Arup and Partners 13 Fitzroy StreetLondonW1T 4BQUK Department of Civil Environmental&Geomatic EngineeringUniversity College LondonChadwick BuildingGower StreetLondonWC1E 6BTUK

This paper draws lessons learnt from a comprehensive case study in overconsolidated clay. Apart from the introduction of the case study, including field measurements, the paper draws on the observations and a three-dimensional（3 D） numerical analysis to discuss the implications of observations in the application of the observational method（OM） in the context of the requirements of EUROCODE 7（EC7）.In particular, we focus on corner effects and time-dependent movements and provide initial guidance on how these could be considered. Additionally, we present the validation of a new set of parameters to check that it provides a satisfactory compliance with EC7 as a set of design parameters. All these findings and recommendations are particularly important for those who want to use the OM in similar future projects.

关键词： Deep excavation Basement Ground movements Wall movements Retaining wall Corner effects Time-dependent movements

Detecting patterns of climate change in long-term forecasts of marine environmental parameters

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International Journal of Digital Earth 2020年第5期13卷 567-585页

作者： Gianpaolo Coro Pasquale Pagano anton Ellenbroek Istituto di Scienza e Tecnologie dell’Informazione“A.Faedo”–CNR PisaItaly b Food and Agriculture Organization of the United Nations(FAO) RomeItaly

Forecasting environmental parameters in the distant future requires complex modelling and large computational *** to the sensitivity and complexity of forecast models,long-term parameter forecasts(*** to 2100)are uncommon and only produced by a few organisations,in heterogeneous formats and based on different assumptions of greenhouse gases ***,data mining techniques can be used to coerce the data to a uniform time and spatial representation,which facilitates their use in many *** this paper,streams of big data coming from AquaMaps and NASA collections of 126 long-term forecasts of nine types of environmental parameters are processed through a cloud computing platform in order to(i)standardise and harmonise the data representations,(ii)produce intermediate scenarios and new informative parameters,and(iii)align all sets on a common time and spatial *** series crosscorrelation applied to these aligned datasets reveals patterns of climate change and similarities between parameter trends in 10 marine *** results highlight that(i)the Mediterranean Sea may have a standalone‘response’to climate change with respect to other areas,(ii)the Poles are most representative of global forecasted change,and(iii)the trends are generally alarming for most oceans.

关键词： Climate change environmental parameters forecasting environmental parameters time series ecological modelling species distribution modelling AquaMaps NASA Earth Exchange

Functional inequalities on manifolds with non-convex boundary

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Science China Mathematics 2018年第8期61卷 1421-1436页

作者： Lijuan Cheng anton Thalmaier James Thompson Mathematics Research Unit University of Luxembourg Department of Applied Mathematics Zhejiang University of Technology

In this article, new curvature conditions are introduced to establish functional inequalities including gradient estimates, Harnack inequalities and transportation-cost inequalities on manifolds with non-convex boundary.

关键词： Ricci curvature gradient inequality log-Sobolev inequality geometric flow

Blockchain Energy: Blockchain in Future Energy Systems

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Journal of Electronic Science and Technology 2019年第4期17卷 317-331页

作者： Bernd Teufel anton Sentic Mathias Barmet international institute of management in technology University of Fribourg

The ongoing,in-depth transformation of the electricity sector towards increased use of alternative,renewable energy sources extends beyond a simple decentralisation drive in the electricity *** transformation process is characterised by the interplay of old and new technologies from the energy sector as well as structural coupling with other sectors,such as the information and communications technology(ICT),enabling the technology transfer as well as market entry by information technology(IT)***-based technologies have the potential to play a key role in this transition by offering decentralised interfaces and systems as well as an alternative approach to the current organisation form of the energy *** paper discusses the applicability and prospects for blockchain-based technologies in the energy sector,which are described using the term“blockchain energy”.For the purposes of this study,blockchain energy encompasses all socio-technical and organisational configurations in the energy sector based on the utilisation of the blockchain principle for energy trading,information storage,and/or increased transparency of energy flows and energy *** the following chapters,the authors present and discuss the current transformation in the electricity market,followed by a review of the different utilisation possibilities for blockchain technologies in the energy sector and a discussion of the barriers and potential for blockchain energy using a transition studies ***,the opportunities and risks of blockchain energy are discussed.

关键词： Blockchain energy management crowd energy transition research.

Polypeptide Brushes Grown via Surface-initiated Ring-opening Polymerization of α-Amino Acid N-Carboxyanhydrides

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Chinese Journal of Polymer Science 2015年第7期33卷 931-931,932-946页

作者： Yong Shen 李志波 Harm-anton Klok Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences School of Polymer Science and Engineering Qingdao University of Science and Technology cole Polytechnique Fédérale de Lausanne (EPFL) Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques Laboratoire des Polymères Batiment MXD Station 12 CH-1015 Lausanne Switzerland

Polypeptide brushes are attractive platforms to generate functional and responsive interfaces that are of potential interest due to their possible biodegradability, biocompatibility and tunable secondary structures. Surface-initiated ringopening polymerization（SI-ROP） of α-amino acid N-carboxyanhydrides represents a powerful and versatile strategy to generate polypeptide brushes. This review is an attempt to capture the state-of-the-art in this field and highlights the latest developments in several selected areas. In addition to presenting an overview of the synthetic methods that have been used to generate polypeptide brushes via SI-ROP, this article will discuss the preparation of patterned polypeptide brushes, the conformational properties of surface-tethered polypeptides, ways to control chain orientation at surfaces as well as properties and applications of these thin polymer films.

关键词： Polypeptide brushes Surface α-Amino acid N-carboxyanhydrides Ring-opening polymerization Secondary structure

Surgery for obstructed defecation syndrome-is there an ideal technique

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World Journal of Gastroenterology 2015年第1期21卷 1-5页

作者： Stefan Riss anton Stift Department of General Surgery Medical University of ViennaA-1090 ViennaAustria

Obstructive defecation syndrome(ODS) is a common disorder with a considerable impact on the quality of life of affected *** for ODS remains a challenging *** exists a great variety of operative techniques to treat patients with *** to the surgeon's preference the approach can be transanal,transvaginal,transperineal or *** techniques have its advantages and ***,high evidence based studies are significantly lacking in literature,thus making accurate assessments *** patient's selection is crucial to achieveoptimal functional *** is mandatory to assess not only defecation disorders but also evaluate overall pelvic floor symptoms,such as fecal incontinence and urinary disorders for choosing an appropriate and tailored *** investigation is essential but may not explain complaints of every patient.

关键词： Obstructive defecation syndrome Defecatory disorde

Genetic link between saline and carbonatitic mantle fluids:The system NaCl-CaCO_(3)-MgCO_(3)±H_(2)O±Fe^(0) at 6 GPa

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Geoscience Frontiers 2022年第6期13卷 59-74页

作者： anton Shatskiy Ivan V.Podborodnikov anton V.Arefiev Altyna Bekhtenova Konstantin D.Litasov Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Science Moscow 119991Russia Vereshchagin Institute for High Pressure Physics of the Russian Academy of Science TroitskMoscow108840Russia

Melt inclusions in kimberlitic minerals and diamonds indicate that chlorides are important constituents of mantle carbonatite ***,alkaline chlorides are important constituents of saline high-density fluids(HDFs)found in diamonds from kimberlites and placers around the *** compositional variations suggest that saline and carbonatitic HDFs could be genetically ***,the essence of this link remains unclear owing to the lack of data on phase relations in the chloridecarbonate systems under *** we studied subsolidus and melting phase relations in the system NaCl–CaCO_(3)–MgCO_(3)at 6 GPa and 1000–1600℃using a Kawai-type multianvil *** found that at 1000℃,subsolidus assemblage consists of halite,magnesite,and *** higher temperatures,the stabilization of dolomite splits the subsolidus area into two partial ternary fields:halite+magnesite+dolomite and halite+dolomite+*** minimum on the liquidus surface corresponds to the halite-dolomite-aragonite ternary eutectic,situated at 1100℃.The eutectic melt has Ca#89 and contains 30 wt.%Na Cl(26 mol%2NaCl).The system has two ternary peritectics:halite+dolomite=magnesite+liquid located near the ternary eutectic and magnesite+dolomite=Mg-dolomite+liquid situated between 1300 and 1400℃.Although under dry conditions incipient melting yields carbonatedominated melt,the addition of water facilitates the fusion of Na Cl and expands the liquid field to Na Cl-rich compositions with up to 70 wt.%Na *** obtained results favor the idea that hydrous saline melts/fluids(brines)found as inclusions in diamonds could be a lower temperature derivative of mantle carbonatite melts and disagree with the hypothesis on chloride melt generation owing to the chloridecarbonate liquid immiscibility since no such immiscibility was *** also studied the interaction of the NaCl–CaCO_(3)–MgCO_(3)system with iron metal and found that carbonate reduction produces Cbearing species(Fe^(0)

关键词： Chloride Carbonate Halite Melting T-X diagram Earth’s mantle