990 resultados para 187-1164
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Hoy en día la información sufre una evolución y transformación constantes, y para cualquier análisis o estudio hay que tener muy en cuenta las fuentes de información existentes en internet. El objetivo de este artículo es hacer un recorrido por la red centrando el interés en la selección de fuentes de información económica y empresarial. A la hora de seleccionar las fuentes electrónicas disponibles hay que tener en cuenta la diversa tipología documental existente: publicaciones periódicas, monografías, workingpapers, tesis, informes, actas de congresos, normas, patentes, etc.
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Volume 187 n. 1
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本书阐明了板壳断裂理论的基础。论证了Reissner型板壳断裂理论的科学性、经典板壳断裂理论的缺陷及在一定范围内仍具有的实用价值;介绍了作者所创意的研究Reissner型板壳断裂纹尖端场的方法等。
目录
- §1.1 板壳弯曲断裂问题
- §1.2 Kirchhoff经典板壳弯曲断裂理论
- §1.3 Reissner型板壳弯曲断裂理论
- §1.4 Kirchhoff与Reissner型板壳弯曲断裂理论的比较
- §1.5 含裂纹有限尺寸板壳断裂分析的局部-整体法
- §1.6 含表面裂纹板壳
- §2.1 Kirchhoff板的基本概念和基本假定
- §2.2 基本公式与弹性曲面微分方程
- §2.3 边界条件
- §2.4 弹性薄板的应变能
- §2.5 极坐标下的挠曲面微分方程与内力公式
- §2.6 裂纹尖端场特征展开式通项公式
- §2.7 Kirchhoff板弯曲应力强度因子
- §3.1 基本方程和公式的复变函数表示
- §3.2 所引入函数的确定程度与一般形式
- §3.3 坐标变换与边界条件
- §3.4 运用保角变换方法求解孔口问题
- §3.5 应力强度因子与函数Φ(z)的关系
- §3.6 复变-主部分析法之应用简例
- §3.7 共直线裂纹问题的一般解答
- §3.8 典型弯曲裂纹问题的解答及弯曲应力强度因子公式
- §3.9 共圆曲线裂纹问题的解答及弯曲应力强度因子公式
- §4.1 裂纹尖端奇异元的位移模式与弯曲应力强度因子
- §4.2 裂纹尖端奇异元的刚度矩阵
- §4.3 裂纹尖端奇异元与常规单元的连接
- §4.4 解析法与数值法的结果比较与讨论
- §4.5 两共线半无限裂纹问题的定解条件及解的实用价值
- §5.1 Reissner型板的基本假定
- §5.2 Reissner型板的基本公式与平衡微分方程
- §5.3 基本方程的简化
- §5.4 边界条件
- §5.5 极坐标下的基本公式与平衡微分方程
- §5.6 两种平板理论用于无裂纹板时的比较
- §5.7 两种乎板理论用于含裂纹板时的比较
- §6.1 基本方程和一般求解方法
- §9.1 局部-整体法与其它解析和数值法的结果比较
- §9.2 边界对应力强度因子的影响
- §9.3 板的支承条件及长宽比的影响
- §9.5 计算Reissner型板应力强度因子的一组近似方程与近似解法
- §9.4 Reissner型板理论与Kirchhoff板理论所得应力强度因子的比较
- §9.6 关于数值计算的几点讨论
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Table of Contents
1 | Introduction | 1 |
1.1 | What is an Adiabatic Shear Band? | 1 |
1.2 | The Importance of Adiabatic Shear Bands | 6 |
1.3 | Where Adiabatic Shear Bands Occur | 10 |
1.4 | Historical Aspects of Shear Bands | 11 |
1.5 | Adiabatic Shear Bands and Fracture Maps | 14 |
1.6 | Scope of the Book | 20 |
2 | Characteristic Aspects of Adiabatic Shear Bands | 24 |
2.1 | General Features | 24 |
2.2 | Deformed Bands | 27 |
2.3 | Transformed Bands | 28 |
2.4 | Variables Relevant to Adiabatic Shear Banding | 35 |
2.5 | Adiabatic Shear Bands in Non-Metals | 44 |
3 | Fracture and Damage Related to Adiabatic Shear Bands | 54 |
3.1 | Adiabatic Shear Band Induced Fracture | 54 |
3.2 | Microscopic Damage in Adiabatic Shear Bands | 57 |
3.3 | Metallurgical Implications | 69 |
3.4 | Effects of Stress State | 73 |
4 | Testing Methods | 76 |
4.1 | General Requirements and Remarks | 76 |
4.2 | Dynamic Torsion Tests | 80 |
4.3 | Dynamic Compression Tests | 91 |
4.4 | Contained Cylinder Tests | 95 |
4.5 | Transient Measurements | 98 |
5 | Constitutive Equations | 104 |
5.1 | Effect of Strain Rate on Stress-Strain Behaviour | 104 |
5.2 | Strain-Rate History Effects | 110 |
5.3 | Effect of Temperature on Stress-Strain Behaviour | 114 |
5.4 | Constitutive Equations for Non-Metals | 124 |
6 | Occurrence of Adiabatic Shear Bands | 125 |
6.1 | Empirical Criteria | 125 |
6.2 | One-Dimensional Equations and Linear Instability Analysis | 134 |
6.3 | Localization Analysis | 140 |
6.4 | Experimental Verification | 146 |
7 | Formation and Evolution of Shear Bands | 155 |
7.1 | Post-Instability Phenomena | 156 |
7.2 | Scaling and Approximations | 162 |
7.3 | Wave Trapping and Viscous Dissipation | 167 |
7.4 | The Intermediate Stage and the Formation of Adiabatic Shear Bands | 171 |
7.5 | Late Stage Behaviour and Post-Mortem Morphology | 179 |
7.6 | Adiabatic Shear Bands in Multi-Dimensional Stress States | 187 |
8 | Numerical Studies of Adiabatic Shear Bands | 194 |
8.1 | Objects, Problems and Techniques Involved in Numerical Simulations | 194 |
8.2 | One-Dimensional Simulation of Adiabatic Shear Banding | 199 |
8.3 | Simulation with Adaptive Finite Element Methods | 213 |
8.4 | Adiabatic Shear Bands in the Plane Strain Stress State | 218 |
9 | Selected Topics in Impact Dynamics | 229 |
9.1 | Planar Impact | 230 |
9.2 | Fragmentation | 237 |
9.3 | Penetration | 244 |
9.4 | Erosion | 255 |
9.5 | Ignition of Explosives | 261 |
9.6 | Explosive Welding | 268 |
10 | Selected Topics in Metalworking | 273 |
10.1 | Classification of Processes | 273 |
10.2 | Upsetting | 276 |
10.3 | Metalcutting | 286 |
10.4 | Blanking | 293 |
Appendices | 297 | |
A | Quick Reference | 298 |
B | Specific Heat and Thermal Conductivity | 301 |
C | Thermal Softening and Related Temperature Dependence | 312 |
D | Materials Showing Adiabatic Shear Bands | 335 |
E | Specification of Selected Materials Showing Adiabatic Shear Bands | 341 |
F | Conversion Factors | 357 |
References | 358 | |
Author Index | 369 | |
Subject Index | 375 |
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目录
- 1.1 化合物的生成焓,反应焓及燃烧热
- 1.2 热化学定律
- 1.3 热力学平衡与自由能,化学平衡与反应自由能
- 1.4 质量作用定律及可逆反应的平衡常数
- 1.5 平衡常数和标准反应自由能的关系
- 1.6 温度和压力对平衡常数的影响
- 1.7 绝热火焰温度计算
- 1.8 化学动力学中采用的几个基本概念和定义
- 1.9 反应的分类
- 1.10 阿累尼乌斯(Arrhenius)定律
- 1.11 双分子反应碰撞理论
- 1.12 反应分子数及反应级数
- 1.13 影响化学反应的因素
- 1.14 链锁反应
- 5.1 燃烧波的两种形式――缓燃(或火焰正常传播)及爆震
- 5.3 马兰特和利-恰及利耶的简化分析法
- 5.4 层流火焰传播速度的无量纲分析法
- 5.5 泽尔多维奇和弗朗克-卡门涅茨基的分区近似解
- 5.6 分区近似解的改进
- 5.7 精确解
- 5.8 物理化学参数对S1的影响及对火焰厚度的影响
- 5.9 火焰传播界限
- 5.10 用层流火焰传播速度计算化学动力参数的方法
- 5.11 火焰的基本性质及火焰的几何学
- 5.12 本生灯火焰稳定的条件
- 5.13 层流火焰传播速度的实验测定
- 5.14 单组元燃料滴燃烧
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This dissertation is an assessment of the status of odontocetes in Hawaiian waters focussing on O´ahu. The work builds on available literature, and on data collected by the author and by others in Hawaiian waters. Abundance and distribution patterns of odontocetes were derived from stranding and aerial survey data. A stranding network operated by the National Marine Fisheries Service, Pacific Area Office collected 187 stranding reports throughout the main Hawaiian Islands between 1937 and 2002. These reports included 16 odontocete species. Number of stranding reports increased over time and was highest on O´ahu. Strandings occurred throughout the year. The difference in number of strandings per month was not significant. Fifteen of the 16 species reported in the stranding record for the main Hawaiian Islands were also reported by aerial survey studies of the area between 1993 and 1998. Only 7 of the species reported were detected during aerial transects around O′ahu between 1998 and 2000. Based on the stranding record, Kogia sp., melon-headed whales, striped dolphins and dwarf killer whale appear to be more common than suggested by aerial surveys. Conversely, pilot whales and bottlenose dolphins were more common, according to aerial surveys, than predicted by the stranding data. Aerial surveys of waters between 0 and 500m around the Island of O′ahu showed that the most abundant species by frequency of occurrence was the pilot whale (30% of sightings), followed by the spinner (16%) and bottlenose dolphin (14%). Because of small sample size, abundance estimates for odontocetes have a high level of uncertainty. The unavailability of a correction factor for g(0)<1, and the reduced visibility below the aircraft further reduced accuracy and increased the inherent underestimation in the data. The most abundant species according to distance sampling estimates were spotted dolphins, pilot whales, false killer whales and spinner dolphins. A natural factor shaping the ecology of odontocete populations is predation pressure both by other odontocetes and, more frequently, by sharks. An account of predation by a tiger shark on a spotted dolphin near Penguin Banks is used as an example of the potential mechanisms of predation by sharks on odontocetes.
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[EN] This article investigates the question of the licensing of null arguments in the so-called pro-drop languages. By focusing on the licensing of null subjects in the different types of -T(Z)E nominalizations in Basque, it aims at defining in a precise way the crucial feature that makes pro-drop possible in a clause. The central claim is that what licenses subject-drop is the assignment of structural Case. That is, it is argued that a subject can be null if and only if it is assigned structural Case. Different aspects of T(Z)E nominalizations are also explored, which show that even if these clauses are similar in the surface, they can be syntactically very different and furthermore, that infinitive clauses marked with the same nominalizing morpheme can also have diverging structures.
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Uno de los objetivos de este artículo ha sido identificar el modo en que las nuevas formas organizativas suponen una transformación drástica con respecto a los modelos tradicionales. Los nuevos modelos y, en particular, el de organización virtual supone la aparición de un nuevo marco conceptual. La innovación no reside tanto en que se abordan nuevas soluciones para los problemas, como en la transformación de los propios problemas y cuestiones clave.
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El objetivo de este artículo es diseñar una estrategia de búsqueda que nos ayude a localizar información sobre un tema concreto: Ética, economía y empresa. El punto de partida será una estrategia de búsqueda determinada que servirá como excusa para consultar una selección de diversas fuentes de información: catálogo de la biblioteca, bases de datos y revistas electrónicas. Para finalizar el articulo se propone como instrumento para seleccionar resultados el factor de impacto JCR y como medio mara gestionar las referencias bibliográficas el gestor Reference Manager
Influencia de la edad y la menopausia en el origen de la Dehiscencia del Canal Semicircular Superior
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145 p. : il., col.
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Começou a ser distribuído hoje o parecer do relator Bernardo Cabral às duas mil emendas apresentadas ao projeto de Constituição. O relator deu parecer a favor de 30% das emendas, rejeitando a maioria. As emendas com 280 assinaturas nem sempre receberam parecer favorável, mas foram todas acolhidas. De acordo com o novo Regimento, o parecer do Relator tem importância secundária, porque todos os artigos terão que ser votados no Plenário. Caso a emenda não tenha sido aprovada pelo relator, o constituinte pode apresentar um destaque para que o assunto volte a análise de todos os constituintes. Constituintes fazem um gráfico em que evidencia os assuntos consensuais. A partir de amanhã começa a faze do pedido de destaque. Os constituintes terão até a segunda feira, às 6 da tarde para apresentar os seus pedidos. Cada constituinte tem direito a 6 destaques. O destaque para votação em separado precisa de 187 assinaturas. As matérias da Ordem econômica e da Ordem social, receberá atenção especial. Constituintes encontram dificuldades diante das restrições do Regimento.
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Analisa o debate em torno da atividade dos grupos de pressão, especialmente a sua regulamentação, prática essa também conhecida como lobby. Para isso, dividiu-se a análise em quatro partes, incluindo conceitos, teorias consagradas, formas e mecanismos de atuação e as possibilidades de regulamentação da atividade no Brasil.
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The aim of this study was to examine areas in which fishermen cooperatives can become involved and then suggest operational guidelines in order to increase fishermen income and also to make the Green Revolution Programme a success through increased production of fish. The paper enumerated different areas in which fishermen cooperatives can participate. These include: thrift and credits, thrift and savings, consumers and building cooperative societies. It is the belief of the author that the expansion of fishermen cooperatives into the areas mentioned in this paper can enable members to process and market their products more economically, buy supplies and equipment in large quantities and obtain lower cost credit