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Tessellations in GIS:Part I—putting it all together

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Geo-Spatial Information Science 2016年第1期19卷 9-25页

作者： Christopher gold Faculty of Computing Engineering and ScienceUniversity of South WalesWalesUK Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing(LIESMARS)Wuhan UniversityWuhanChina

This article attempts to describe the role of tessellated models of space within the discipline of geographic information systems(GIS)—a speciality coming largely out of geography and land surveying,where there was a strong need to represent information about the land’s surface within a computer system rather than on the original paper *** look at some of the basic operations in GIS,including dynamic and kinetic *** examine issues of topology and data structures and produce a tessellation model that may be widely applied both to traditional“object”and“field”data *** on this framework,it can be argued that tessellation models are fundamental to our understanding and processing of geographical space,and provide a coherent framework for understanding the“space”in which we *** first article examines static structures,and a subsequent article looks at“change”—what happens when things move.

关键词： GIS tessellation model static structure topology data structure object and field Voronoi diagram

Fragmentation model for large L/D (Length over Diameter) explosive fragmentation warheads

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Defence Technology（防务技术） 2017年第4期13卷 300-309页

作者： Vladimir M. gold US Army RDECOM-ARDEC Attn: RDAR-MEE-F Picatinny Arsenal NJ 07806-5000 USA

New advanced numerical computer model enabling accurate simulation of fragmentation parameters of large Length over Diameter(L/D)explosively driven metal shells has been developed and *** newly developed large L/D multi-region model links three-dimensional axisymmetric high strain high strain-rate hydrocode analyses with the conventional set of Picatinny Arsenal FRAGmentation(PAFRAG)simulation *** standard PAFRAG modeling technique is based on the Mott's theory of break-up of idealized cylindrical"ring-bombs",in which the length of the average fragment is a function of the radius and velocity of the shell at the moment of break-up,and the mechanical properties of the *** the newly developed multi-region model,each of the shell region,the break-up is assumed to occur instantaneously,whereas the entire shell is modeled to fragment at multiple times,according to the number of the regions *** to PAFRAG methodology,the required input for both the natural and the controlled fragmentation models including the geometry and the velocity of the shell at moment of break-up had been provided from the hydrocode analyses and validated with available experimental *** newly developed large L/D multi-region PAFRAG model has been shown to accurately reproduce available experimental fragmentation data.

关键词： Explosive fragmentation modeling Natural fragmentation Mott model PAFRAG Fragmentation warhead lethality performance

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

The topological viewshed:embedding topological pointers into digital terrain models to improve GIS capability for visual landscape analysis

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International Journal of Digital Earth 2016年第12期9卷 1185-1205页

作者： N.Sang C.gold D.Miller Department of Landscape Architecture Planning and Management Swedish University of Agricultural ScienceAlnarpSweden AnserGIS AB LundSweden Department of Computing and Mathematics University of South WalesPontypriddUK The James Hutton Institute AberdeenUK

The effort to develop a Digital Earth has made dramatic progress in terms of visualisation and visual data integration for use-cases which demand semantically rich *** provide this analysis and ensure legitimate representations of the spatial data from which visualisation are derived,it is necessary to provide more comprehensive analytical capabilities of the *** of aesthetic valuation of landscape require a richer analytical response than simply‘whether and possibly how much of’an object or area of land can be *** requires interrogation of the scene as it appears and to distinguish between transient visual effects and those locally invariant to view point *** paper explores a data structure to support scene *** such,it first reviews the existing techniques from the fields of GIS and computer graphics as to their potential and limitations in providing a qualitatively more nuanced visual *** then introduces a new method of encoding visually apparent relationships into terrain models.A prototype implementation is presented based on the Quad-Edge Triangular Irregular Network,though it is believed that raster or vector implementation would be *** developed primarily with landscape analysis in mind,the method could have wider applicability.

关键词： Visibility analysis landscape topology viewshed

Nanoparticles for targeted cancer radiotherapy

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Nano Research 2020年第11期13卷 2887-2897页

作者： roger M.Pallares Rebecca J.Abergel Chemical Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Nuclear Engineering University of CaliforniaBerkeleyCA94720USA

Radiotherapy,where ionizing radiation is locally delivered either through an external beam or by surgically implanting radionuclide-based seeds in the tumor,is one of the gold standard treatments for *** to the non-selective nature of radiation,healthy tissue surrounding the cancerous region is usually affected by the ***,new strategies,including targeted alpha therapy,are being studied to improve the selectivity of the treatment and minimize side *** challenges,however,limit the current development of targeted radiotherapy,such as the functionalization of the therapeutic agent with targeting vectors and controlling the release of recoiling *** offer unique opportunities as drug delivery vehicles,since they are biocompatible,enhance the cellular uptake of drugs,and are easily functionalized with targeting *** this review,we examine how nanoparticles can be used for targeted radiotherapy,either as sensitizers of external beams or as delivery vehicles for therapeutic *** describe the clinical relevance of different types of nanoparticles,followed by an analysis of how these nanoconstructs can solve some of the main limitations of conventional ***,we critically discuss the current situation of nanoparticle-based radiotherapy in clinical settings and challenges that need to be overcome in the future for further development of the field.

关键词： radiotherapy targeted cancer radiotherapy nanoparticles cancer targeted alpha therapy external beam

Color characteristics of Cu-Zn-Al alloys

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中国有色金属学会会刊：英文版 1994年第3期4卷 89-92页

作者： Li, Baomian Zhang, Xiuhua(Shenyang Institute of gold Technology, Shenyang 110015)

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关键词： Cu-Zn-Al alloys color chromaticity parameters color difference

Assessing keloid recurrence following surgical excision and radiation

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Burns & Trauma 2020年第1期8卷 34-40页

作者： Michael H.gold Mark S.Nestor Brian Berman David goldberg gold Skin Care Center 2000 Richard Jones RoadSuite 220NashvilleTN 37215 Center for Clinical and Cosmetic Research 2925 NE 199th StSuite 205AventuraFL 33180 Department of Dermatology and Cutaneous Surgery University of Miami Miller School of MedicineMiamiFL Skin Laser&Surgery Specialists of NY/NJ 110 E.55th Street13th floorNew YorkNY 10022

Keloids are a fibroproliferative disorder that can result from a cutaneous injury to the reticular *** rates as high as 100%have been reported following surgical excision ***,a variety of post-surgical techniques have been employed to prevent keloid recurrence,including the use of *** numerous studies have shown post-excisional X-rays,electron beam,lasers and brachytherapy can reduce the rate of keloid recurrence,numerous inconsistencies,including a wide range of definitions for keloid recurrence,make it difficult to compare study *** review aims to examine the various means for defining keloid recurrence in clinical trials involving the use of radiation *** of the Cochrane Library and PubMed were performed to identify the available information for post-surgical keloid recurrence following radiation *** identified study was reviewed for patient followup and criteria used to define keloid *** search results included clinical studies with external beam radiation,brachytherapy and superficial radiation *** studies did not include a definition of keloid recurrence,or defined recurrence only as the return of scar *** studies defined keloid recurrence based on patient self-assessment questionnaires,symptoms and scar elevation and changes in Kyoto Scar Scale,Japan Scar Workshop Scale and Vancouver Scar Scale *** results of this review indicate keloidectomy followed by radiation therapy provide satisfactory recurrence rates;however,clinical studies evaluating these treatments do not describe treatment outcomes or use different definitions of keloid ***,recurrence rates vary widely,making comparisons across studies *** recurrence should be clearly defined using both objective and subjective measures.

关键词： Keloid Keloid scar Recurrence External beam radiation Brachytherapy Superficial radiation therapy

Pulsation Solution to the Equation of Earth's Gravitational Field (Main Outcome)

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 297-300页

作者： JIANG Zhi gold Headquarters, P.O.Box 9902, Beijing 100102 gold Headquarters Beijing 100102 Peoples R China

Using d'Alembert equation as the approximation of Einstein's equation, a solution is given in this paper to the time-dependent gravitational equation of the Earth in consideration of the Earth's features, which describes the characteristics of pulsation of the Earth and the structures of spherical layers of its interior, thus providing a theoretical basis for establishing the idea of mantle pulsation.

关键词： d'Alembert equation formula of gravitational field spherical layers density model mantle pulsation

IMPROVING 9-INTERSECTION MODEL BY REPLACING THE COMPLEMENT WITH VORONOI REGION

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Geo-Spatial Information Science 2000年第1期3卷 1-10页

作者： CHEN Jun LI Chengming LI Zhilin gold C M National Geomatics Center of China Beijling China

9-intersection model is the most popular framework used for formalizing the spatial relations between two spatial objectsA andB. It transforms the topological relationships between two simple spatial objectsA andB into point-set topology problem in terms of the intersections ofA’s boundary (?A), interior (A 0) and (A ?) withB’s boundary (?B), interior (B 0) and exterior (B ?). It is shown in this paper that there exist some limitations of the original 9-intersection model due to its definition of an object’s exterior as its complement, and it is difficult to distinguish different disjoint relations and relations between complex objects with holes, difficult or even impossible to compute the intersections with the two object’s complements (?A∩B ?,A 0∩?B ?,A ?∩?B,A ?∩B 0 andA ?∩B ?)since the complements are infinitive. The authors suggest to re-define the exterior of spatial object by replacing the complement with its Voronoi region. A new Voronoi-based 9-intersection (VNI) is proposed and used for formalizing topological relations between spatial bojects. By improving the 9-intersection model, it is now possible to distinguish disjoint relations and to deal with objects with holes. Also it is possible to compute the exterior-based intersections and manipulate spatial relations with the VNI.

关键词： 9-intersection model Voronoi region topological relationship