Discussing embedded systems in general is difficult, because each embedded system is unique. Rather than presenting a list of general Principles for handling embedded development issues, this book presents examples of problems encountered and solutions to those problems using real hardware and software. In that sense, it is a “cookbook” for developers that offers design “recipes” that can be elaborated on or modified as needed to solve other design problems.
The book consists of three sections. The first, foundations, provides a tutorial overview of the Principles underlying data mining algorithms and their application. The presentation emphasizes intuition rather than rigor. The second section, data mining algorithms, shows how algorithms are constructed to solve specific problems in a principled manner. The algorithms covered include trees and rules for classification and regression, association rules, belief networks, classical statistical models, nonlinear models such as neural networks, and local memory-based models. The third section shows how all of the preceding analysis fits together when applied to real-world data mining problems. Topics include the role of metadata, how to handle missing data, and data preprocessing.
matlab有限元網格劃分程序
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.
This report presents a tutorial of fundamental array processing and beamforming theory relevant to microphone array speech processing. A microphone array consists of multiple microphones placed at different spatial locations. Built upon a knowledge of sound propagation Principles, the multiple inputs can be manipulated to enhance or attenuate signals emanating from particular directions. In this way, microphone arrays provide a means of enhancing a desired signal in the presence of corrupting noise sources. Moreover, this enhancement is based purely on knowledge of the source location, and so microphone array techniques are applicable to a wide variety of noise types. Microphone arrays have great potential in practical applications of speech processing, due to their ability to provide both noise robustness and hands-free signal acquisition.
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
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.
The new digital radio system DAB (Digital Audio Broadcasting, nowadays often called
Digital Radio) is a very innovative and universal multimedia broadcast system which will
replace the existing AM and FM audio broadcast services in many parts of the world in
the future. It was developed in the 1990s by the Eureka 147/DAB project. DAB is very
well suited for mobile reception and provides very high robustness against multipath
reception. It allows use of single frequency networks (SFNs) for high frequency
efficiency.
This book is an entry-level text on the technology of telecommunications. It has been
crafted with the newcomer in mind. The twenty-one chapters of text have been prepared
for high-school graduates who understand algebra, logarithms, and the basic Principles of
electricity such as Ohm’s law. However, it is appreciated that many readers require support
in these areas. Appendices A and B review the essentials of electricity and mathematics
up through logarithms. This material was placed in the appendices so as not to distract
from the main theme, the technology of telecommunication systems. Another topic that
many in the industry find difficult is the use of decibels and derived units. Appendix C
provides the reader a basic understanding of decibels and their applications. The only
mathematics necessary is an understanding of the powers of ten
This book is intended for RF planners, to serve as a practical tool in their daily work
designing indoor radio distribution systems.
Based on feedback from readers of the first edition it was clear to me that I needed to add
more material and in depth description of the basics of indoor systems based on using
repeaters; this has grown into a new Section 4.7.
There was also a strong demand to add more detail and dedicate a full chapter to radio
planning in tunnels, for both rail and road tunnels; and redundancy Principles in the design
focus for solving the challenge of handover zones. An entire Chapter 11 is now dedicated to
tunnel radio planning.
