检索结果-内蒙古大学图书馆

A Boolean characterization of three-dimensional simple points

PATTERN RECOGNITION LETTERS 1996年第2期17卷 115-124页

作者： Bertrand, G Laboratoire PSI ESIEE Citi Descartes BP 99 93162 Noisy-le-Grand Cedex France

A simple point in a binary digital picture is a point belonging to the object whose removal does not change the basic connectivity features of the image. In this paper, we propose a Boolean characterization of three-dimensional simple points in cubic grids. This characterization requires the checking of 5 basic configurations in the neighborhood of the point considered.

关键词： simple points three-dimensional cubic grids thinning algorithms discrete topology

来源：评论

学校读者我要写书评

暂无评论

Residuals plus directional gaps equals skeletons

引用

PATTERN RECOGNITION LETTERS 1997年第4期18卷 343-353页

作者： Cardoner, R Thomas, F UPC CSIC INST ROBOT & INFORMAT IND BARCELONA 08034 SPAIN

Many thinning algorithms for 2D binary images, or modifications of existing ones, have been proposed in recent years. The one given herein is surprisingly simple compared to most of them, and still it has theoretically favorable properties. Actually, it provides a connected - single-pixel in width whenever possible - well-centered homototic skeleton that allows shapes to be nearly reconstructed. In addition to these properties, it is also very attractive because of its generalization to higher dimensions. The presented algorithm is based on the application of directional erosions, while retaining those pixels that introduce disconnections. It is shown how this strategy is specially well-suited for run-length encoded images, leading to a very fast and simple thinning algorithm. (C) 1997 Elsevier Science B.V.

关键词： thinning algorithms skeletons run-length encoding mathematical morphology

来源：评论

学校读者我要写书评

暂无评论

SIMPLE POINTS, TOPOLOGICAL NUMBERS AND GEODESIC NEIGHBORHOODS IN CUBIC GRIDS

引用

PATTERN RECOGNITION LETTERS 1994年第10期15卷 1003-1011页

作者： BERTRAND, G ESIEE Cit&eacute Descartes B.P. 99 93162 Noisy-Le-Grand Cedex France

We introduce the notion of geodesic neighborhood in order to define some topological numbers associated with a point in a three-dimensional cubic grid. For {6, 26} and {6, 18} connectivities, these numbers lead to a c... 详细信息

关键词： SIMPLE POINTS 3 DIMENSIONS DIGITAL TOPOLOGY thinning algorithms GEODESIC NEIGHBORHOODS CUBIC GRIDS

来源：评论

学校读者我要写书评

暂无评论

Recognition of Atomically-Resolved STM Images of Graphite

引用

JOURNAL OF COMPUTATIONAL AND THEORETICAL NANOSCIENCE 2010年第2期7卷 404-407页

作者： Wang, Maofa Zou, Xiaoping Cheng, Jin Zhu, Guang Su, Yi Yang, Gangqiang Lue, Xueming Beijing Informat Sci & Technol Univ Res Ctr Sensor Technol Beijing Key Lab Sensor Beijing 100101 Peoples R China Minist Educ Key Lab Modern Measurement & Control Technol Beijing 100101 Peoples R China

It is important and interesting thing to recognize the atomic structure of graphite by processing graphite STM images, which is useful to automatically give the hexagonal topology structure during in-situ STM scanning of graphite. In this paper, we report some digital image processing algorithm applications on the recognition of atomic structure of graphite. At last, we also write the software with c(++) codes, which applying the digital image processing algorithms. And from the result of processing a typical STM image of graphite, we can clearly see graphite hexagon structure.

关键词： Graphite STM Digital Image Processing thinning algorithms Mathematical Morphology

来源：评论

学校读者我要写书评

暂无评论

Estimating the volume of tephra deposits: A new simple strategy

引用

GEOLOGY 2012年第5期40卷 415-418页

作者： Bonadonna, C. Costa, A. Univ Geneva CH-1205 Geneva Switzerland Univ Reading Reading RG6 6AH Berks England Ist Nazl Geofis & Vulcanol I-80125 Naples Italy

Volume determination of tephra deposits is necessary for the assessment of the dynamics and hazards of explosive volcanoes. Several methods have been proposed during the past 40 years that include the analysis of crystal concentration of large pumices, integrations of various thinning relationships, and the inversion of field observations using analytical and computational models. Regardless of their strong dependence on tephra-deposit exposure and distribution of isomass/isopach contours, empirical integrations of deposit thinning trends still represent the most widely adopted strategy due to their practical and fast application. The most recent methods involve the best fitting of thinning data using various exponential segments or a power-law curve on semilog plots of thickness (or mass/area) versus square root of isopach area. The exponential method is mainly sensitive to the number and the choice of straight segments, whereas the power-law method can better reproduce the natural thinning of tephra deposits but is strongly sensitive to the proximal or distal extreme of integration. We analyze a large data set of tephra deposits and propose a new empirical method for the determination of tephra-deposit volumes that is based on the integration of the Weibull function. The new method shows a better agreement with observed data, reconciling the debate on the use of the exponential versus power-law method. In fact, the Weibull best fitting only depends on three free parameters, can well reproduce the gradual thinning of tephra deposits, and does not depend on the choice of arbitrary segments or of arbitrary extremes of integration.

关键词： PUMICE EMPIRICAL research VOLCANIC eruptions WEIBULL distribution thinning algorithms

来源：评论

学校读者我要写书评

暂无评论

Extraction of strokes in handwritten characters

引用

PATTERN RECOGNITION 2000年第7期33卷 1147-1160页

作者： L'Homer, E ENS Cachan CMLA DIAM F-94235 Cachan France

Among the many handwritten character recognition algorithms that have been proposed in the past few years, few of them use models which are able to simulate handwriting. This can be explained by the fact that simulation models require the estimation of strokes starting from statistic images of letters, while crossing and overlapping strokes make this estimation difficult. The approach we suggest is to efficiently deal with crossing areas and overlaps using parametric representations of lines and thickness of stroke: a probabilistic model of strokes is described to extract non-overlapping strokes of the image. A bayesian approach using a statistical study and a model of stroke crossing is described that optimizes the reconstruction of crossings and permits to characterize image of letters by robust graphs of curves. (C) 2000 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved.

关键词： handwritten character recognition thinning algorithms graphs of strokes stroke crossing stroke path detection

来源：评论

学校读者我要写书评

暂无评论

On the economics of Norway spruce stands and carbon storage

引用

CANADIAN JOURNAL OF FOREST RESEARCH 2013年第7期43卷 637-648页

作者： Niinimaki, Sami Tahvonen, Olli Makela, Annikki Linkosalo, Tapio Univ Helsinki Dept Forest Sci FI-00014 Helsinki Finland Finnish Forest Res Inst Metla FI-01301 Vantaa Finland

We combine a process-based growth model for even-aged Norway spruce (Picea abies (L.) Karst.) with economics and optimization. Carbon storage is subsidized based on stand growth and product decay. We include detailed optimized thinnings and timber quality features and present cost functions for stand-level CO2 storage. In contrast to earlier studies, our results suggest that changing thinning strategies and postponing thinnings are at least as important as lengthening the rotation period when considering economically efficient carbon storage. The role of thinning is most important in less fertile sites. Contrary to the generic Faustmann model, a higher interest rate increases rotation length on our fertile site. Including carbon release from decaying timber products as reductions from carbon subsidies only has minor effects on optimal solutions. The fertile site stores more discounted carbon. However, with a 1% interest rate, the less fertile site is cost-efficient up to 13 CO2 ***(-1), and with a 3% interest rate, it is cost-efficient up to 14 CO2 ***(-1). After these points, carbon storage on the fertile site becomes cheaper. The economic costs of carbon storage suggest that it is optimal to apply carbon storage in Norway spruce forests to meet greenhouse gas reduction commitments.

关键词： NORWAY spruce RESEARCH ECONOMIC development -- Mathematical models COST functions (Optimization) thinning algorithms FORESTS & forestry GREENHOUSE gas mitigation NORWAY

来源：评论

学校读者我要写书评

暂无评论

A NEW CHARACTERIZATION OF 3-DIMENSIONAL SIMPLE POINTS

引用

PATTERN RECOGNITION LETTERS 1994年第2期15卷 169-175页

作者： BERTRAND, G MALANDAIN, G INRIA F-06902 SOPHIA ANTIPOLISFRANCE

A new characterization of three-dimensional simple points is presented. Unlike previous characterizations, it does not need the calculation of the genus or the number of holes. It only needs the computation of two numbers of connected components in the neighborhood of the considered point. The proof of the validity of the characterization is given.

关键词： SIMPLE POINTS 3 DIMENSIONS DIGITAL TOPOLOGY thinning algorithms

来源：评论

学校读者我要写书评

暂无评论

Silvicultural prescriptions for mixed-species forest stands. A European review and perspective

引用

EUROPEAN JOURNAL OF FOREST RESEARCH 2021年第5期140卷 1267-1294页

作者： Pretzsch, Hans Poschenrieder, Werner Uhl, Enno Brazaitis, Gediminas Makrickiene, Ekaterina Calama, Rafael Tech Univ Munich Sch Life Sci Chair Forest Growth & Yield Sci Hans Carl von Carlowitz Pl 2 D-85354 Freising Weihenstephan Germany Bavarian Inst Forestry Hans Carl von Carlowitz Pl 1 D-85354 Freising Weihenstephan Germany Vytautas Magnus Univ Studentu Inst Forest Biol & Silviculture Str 11 Akad Mstl LT-53361 Kaunas Dist Lithuania INIA iuFOR UVa Forest Res Ctr Dept Forest Dynam & Management Ctra Coruna Km 7-5 Madrid 28040 Spain

Compared with far-developed measures and methods for mono-specific forest stands, the silvicultural prescriptions for mixed-species stands are at their early beginning. However, they are essential for the well-conceived establishment, design, and control of mixed-species stands, currently promoted in many countries worldwide. Here, we review the state of the art and we further develop silvicultural prescriptions for mixed-species stands for steering of experiments, stand modeling, and silviculture. We review which aspects of tree species mixing are most relevant for management goal achievement. We found the maintenance of species diversity and structural heterogeneity for ecological purpose, stabilizing productivity, and social-economic performance as main objectives. We give an overview of quantitatively formulated silvicultural prescriptions for steering mixed-species stands for forest practice, long-term experiments, forest stand models. Compared with the sophisticated guidelines for mono-specific stands, prescriptions for mixed stand are often mainly qualitative and vague. Then, we introduce methodological approaches in development for steering mixture: measures for spatial and temporal separation, species-specific growing space requirements for crop trees, coefficients for equivalence and density modification, and basic relationships for steering tree number and area-based mixing proportions. Finally, we draw conclusions for further development of methodological approaches for silvicultural steering of experiments, implementation in stand simulators, and for silvicultural operations. We see the need for improving the quantitative spatially explicit rules based at tree or cohort level, for substantiating the knowledge on species-specific allometry, growing area, tree-to-tree distances, and position-dependent competition indices for steering tree removal. We discuss the prospects and limitations of establishing silvicultural prescriptions for mixed-species stands

关键词： Species-mixing experiments thinning algorithms Temporal and spatial separation Equivalence coefficients Silvicultural steering Individual tree models Scenario analyses

来源：评论

学校读者我要写书评

暂无评论

CONDITION FOR DIGITAL POINTS REMOVAL

引用

SIGNAL PROCESSING 1979年第4期1卷 283-285页

作者： ARCELLI, C Laboratorio di Cibernetica C.N.R. via Toiano 2 Arco Felice Napoli Italia

Removal operations play a crucial role in most algorithms which transform digital figures into stick-like ones. In this note, digital points that are candidates to deletion are examined and a necessary and sufficient condition for their removal is given. Operationen zur Tilgung von Bildpunkten spielen eine wichtige Rolle in den meisten Algorithmen, die Digitalbilder auf ihr Skelett reduzieren. In dieser werden Kriterien zur Tilgung von Bildpunkten untersucht. Eine notwendige und hinreichende Bedingung für ihre Tilgung wird vorgestellt. Les opérations d'éffacement sont trés importantes dans les algorithmes qui réduisent les images numérisées à leurs squelettes. Dans cette communication, nous examinons les points qui peuvent être effacés et nous presentons une condition necessaire et suffisante qui permet de faire des simples opérations d'éffacement.

关键词： Picture processing binary pictures thinning algorithms removal operations

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：