matlab有限元网格划分程序 DistMesh is a simple MATLAB code for generation of unstructured triangular and tetrahedral meshes. It was developed by Per-Olof Persson (now at UC Berkeley) and Gilbert Strang in the Department of Mathematics at MIT. A detailed description of the program is provided in our SIAM Review paper, see documentation below. One reason that the code is short and simple is that the geometries are specified by Signed Distance Functions. These give the shortest distance from any point in space to the boundary of the domain. The sign is negative inside the region and positive outside. A simple example is the unit circle in 2-D, which has the distance function d=r-1, where r is the distance from the origin. For more complicated geometries the distance function can be computed by interpolation between values on a grid, a common representation for level set methods. For the actual mesh generation, DistMesh uses the Delaunay triangulation routine in MATLAB and tries to optimize the node locations by a force-based smoothing procedure. The topology is regularly updated by Delaunay. The boundary points are only allowed to move tangentially to the boundary by projections using the distance function. This iterative procedure typically results in very well-shaped meshes. Our aim with this code is simplicity, so that everyone can understand the code and modify it according to their needs. The code is not entirely robust (that is, it might not terminate and return a well-shaped mesh), and it is relatively slow. However, our current RESEARCH shows that these issues can be resolved in an optimized C++ code, and we believe our simple MATLAB code is important for demonstration of the underlying principles. To use the code, simply download it from below and run it from MATLAB. For a quick demonstration, type "meshdemo2d" or "meshdemond". For more details see the documentation.
标签： matlab有限元网格划分程序
上传时间： 2015-08-12
上传用户：凛风拂衣袖
Guided vehicles (GVs) are commonly used for the internal transportation of loads in warehouses, production plants and terminals. These guided vehicles can be routed with a variety of vehicle dispatching rules in an attempt to meet performance criteria such as minimizing the average load waiting times. In this RESEARCH, we use simulation models of three companies to evaluate the performance of several real-time vehicle dispatching rules, in part described in the literature. It appears that there is a clear difference in average load waiting time between the different dispatching rules in the different environments. Simple rules, based on load and vehicle proximity (distance-based) perform best for all cases. The penalty for this is a relatively high maximum load waiting time. A distance-based rule with time truncation, giving more priority to loads that have to wait longer than a time threshold, appears to yield the best possible overall performance. A rule that particularly considers load-waiting time performs poor overall. We also show that using little pre-arrival information of loads leads to a significant improvement in the performance of the dispatching rules without changing their performance ranking.
标签： Testing and classifying vehicle dispatching rules in three real-world settings
上传时间： 2016-04-01
上传用户：五块钱的油条
Computational models are commonly used in engineering design and scientific discovery activities for simulating complex physical systems in disciplines such as fluid mechanics, structural dynamics, heat transfer, nonlinear structural mechanics, shock physics, and many others. These simulators can be an enormous aid to engineers who want to develop an understanding and/or predictive capability for complex behaviors typically observed in the corresponding physical systems. Simulators often serve as virtual prototypes, where a set of predefined system parameters, such as size or location dimensions and material properties, are adjusted to improve the performance of a system, as defined by one or more system performance objectives. Such optimization or tuning of the virtual prototype requires executing the simulator, evaluating performance objective(s), and adjusting the system parameters in an iterative, automated, and directed way. System performance objectives can be formulated, for example, to minimize weight, cost, or defects; to limit a critical temperature, stress, or vibration response; or to maximize performance, reliability, throughput, agility, or design robustness. In addition, one would often like to design computer experiments, run parameter studies, or perform uncertainty quantification (UQ). These approaches reveal how system performance changes as a design or uncertain input variable changes. Sampling methods are often used in uncertainty quantification to calculate a distribution on system performance measures, and to understand which uncertain inputs contribute most to the variance of the outputs. A primary goal for Dakota development is to provide engineers and other disciplinary scientists with a systematic and rapid means to obtain improved or optimal designs or understand sensitivity or uncertainty using simulationbased models. These capabilities generally lead to improved designs and system performance in earlier design stages, alleviating dependence on physical prototypes and testing, shortening design cycles, and reducing product development costs. In addition to providing this practical environment for answering system performance questions, the Dakota toolkit provides an extensible platform for the RESEARCH and rapid prototyping of customized methods and meta-algorithms
标签： Optimization and Uncertainty Quantification
上传时间： 2016-04-08
上传用户：huhu123456
信息隐藏软件Outguess的源码 Outguess主要用于JPEg图象的steganography，本软件来自Outguess的作者Provos，欢迎大家下载研究-Information Hiding Outguess source software is mainly used Outguess JPEG image steganography, this software from Outguess author of Provos, welcomed everyone to download RESEARCH
标签： outguess
上传时间： 2017-03-07
上传用户：Liquor
shp 文件修复工具（Shape Checker），解决由于dbf文件和shp文件不一致导致打不开的问题.shape文件修复工具免费下载 由ESRI开发，一个ESRI（Environmental Systems RESEARCH Institute)的shape文件包括一个主文件，一个索引文件，和一个dBASE表，其中主文件的后缀就是.shp。
标签： shape文件修复工具
上传时间： 2020-03-19
上传用户：sun961920936
We review the current applications of photonic technologies to Smart Cities. Inspired by the future needs of Smart Cities, we then propose potential applications of advanced photonic technologies. We find that photonics already has a major impact on Smart Cities, in terms of smart lighting, sensing, and communication technologies. We further find that advanced photonic technologies could lead to vastly improved infrastructure, such as smart water‐supply systems. We conclude by proposing directions for future RESEARCH that will have the greatest impact on realizing Smart City initiatives.
上传时间： 2020-05-26
上传用户：shancjb
Smart City Networks: Through the Internet of Things is composed of RESEARCH results, analyses, and ideas, which focus on a diversity of interconnected factors relating with urbanization, its “smartness,” and overarching “internet of things (IoT).” The latter refers to interconnected objects and devices – through compu- tational operations – which can receive signals and actuate systems.
标签： Networks Internet Through Things Smart City
上传时间： 2020-05-26
上传用户：shancjb
This book provides technical information about all aspects of 3GPP LTE. The areas covered range from basic concepts to RESEARCH-grade material, including future directions. The book captures the current state of 3GPP LTE technology and serves as a source of comprehensive reference material on this subject. It has a total of 12 chapters authored by 50 experts from around the world. The targeted audi- ence includes professionals who are designers or planners for 3GPP LTE systems, RESEARCHers (faculty members and graduate students), and those who would like to learn about this field.
标签： Technology Cellular Radio 3GPP LTE and
上传时间： 2020-05-26
上传用户：shancjb
This book has grown out of my teaching and RESEARCH at the University of Surrey and out of my previous experiences in companies such as Philips, Ascom and Motorola. It is primarily intended for use by students in master’s level and enhanced final-year under- graduate courses who are specialising in communication systems and wish to understand the principles and current practices of the wireless communication channel, including both antenna and propagation aspects
标签： Propagation Antennas
上传时间： 2020-05-26
上传用户：shancjb
Evolutionary Computation (EC) deals with problem solving, optimization, and machine learning techniques inspired by principles of natural evolution and ge- netics. Just from this basic definition, it is clear that one of the main features of the RESEARCH community involved in the study of its theory and in its applications is multidisciplinarity. For this reason, EC has been able to draw the attention of an ever-increasing number of RESEARCHers and practitioners in several fields.
标签： Applications Evolutionary Computing of
上传时间： 2020-05-26
上传用户：shancjb
