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Abstract State Machines, Alloy, B, TLA, VDM, and Z - - Bog - Springer International Publishing AG - Plusbog.dk

Humanizing AI with Personality - Gulnara Z. Karimova - Bog - Springer International Publishing AG - Plusbog.dk

Systems, Functions and Safety - Milan Z. Bjelica - Bog - Springer International Publishing AG - Plusbog.dk

Understanding and Preventing Falls - Stephen Z. Fadem - Bog - Springer International Publishing AG - Plusbog.dk

Understanding and Preventing Falls - Stephen Z. Fadem - Bog - Springer International Publishing AG - Plusbog.dk

Despite the fact that elderly persons have a 33-35% chance of falling and becoming injured, most are ill-prepared. According to the World Health Organization, falls cause over 50% of accidental injuries and 39% of fatal injuries in the elderly. They are the fifth leading cause of death in the general population. Falls can be either non-mechanical, related to underlying illness or debilitation, or they can be mechanical, related to accidental trips and slips and caused by environmental factors such as poor lighting, surprise steps, lack of grab bars, and slippery bathroom floors. Non-mechanical falls can be related to cognitive disorders, such as stroke or dementia, or to frailty. They can also be related to over-medicating with sedatives, diabetic medications, or blood pressure therapy. Falls can be the consequence of aging or chronic diseases such as heart disease, diabetes, kidney disease, or cancer. Patients with any of these disorders may have poor muscle tone, walking disorders, or a loss of equilibrium. Mechanical falls may be completely avoided by fall-proofing the home environment. This book outlines several practical tips for eliminating potential home hazards and reviews each of the major causes of falls to help the patient and his or her caregiver, as well as the health provider, prevent falling by adapting one''s lifestyle. The book also covers exercise programs and community programs that can be established and used to minimize the risk of falling in the elderly. Given that falls are common and that the majority of persons who fall are ill-prepared, this book will raise awareness of fall-prevention measures that can help reduce falls and fall-related injuries.

DKK 301.00
1

Analysis and Design of Transmitarray Antennas - Atef Z. Elsherbeni - Bog - Springer International Publishing AG - Plusbog.dk

Analysis and Design of Transmitarray Antennas - Atef Z. Elsherbeni - Bog - Springer International Publishing AG - Plusbog.dk

In recent years, transmitarray antennas have attracted growing interest with many antenna researchers. Transmitarrays combines both optical and antenna array theory, leading to a low profile design with high gain, high radiation efficiency, and versatile radiation performance for many wireless communication systems. In this book, comprehensive analysis, new methodologies, and novel designs of transmitarray antennas are presented. Detailed analysis for the design of planar space-fed array antennas is presented. The basics of aperture field distribution and the analysis of the array elements are described. The radiation performances (directivity and gain) are discussed using array theory approach, and the impacts of element phase errors are demonstrated. The performance of transmitarray design using multilayer frequency selective surfaces (M-FSS) approach is carefully studied, and the transmission phase limit which are generally independent from the selection ofa specific element shape is revealed. The maximum transmission phase range is determined based on the number of layers, substrate permittivity, and the separations between layers. In order to reduce the transmitarray design complexity and cost, three different methods have been investigated. As a result, one design is performed using quad-layer cross-slot elements with no dielectric material and another using triple-layer spiral dipole elements. Both designs were fabricated and tested at X-Band for deep space communications. Furthermore, the radiation pattern characteristics were studied under different feed polarization conditions and oblique angles of incident field from the feed. New design methodologies are proposed to improve the bandwidth of transmitarray antennas through the control of the transmission phase range of the elements. These design techniques are validated through the fabrication and testing of two quad-layer transmitarray antennas at Ku-band. A single-feed quad-beam transmitarray antenna with 50 degrees elevation separation between the beams is investigated, designed, fabricated, and tested at Ku-band. In summary, various challenges in the analysis and design of transmitarray antennas are addressed in this book. New methodologies to improve the bandwidth of transmitarray antennas have been demonstrated. Several prototypes have been fabricated and tested, demonstrating the desirable features and potential new applications of transmitarray antennas.

DKK 426.00
1

Multi-Modal Face Presentation Attack Detection - Stan Z. Li - Bog - Springer International Publishing AG - Plusbog.dk

Multi-Modal Face Presentation Attack Detection - Stan Z. Li - Bog - Springer International Publishing AG - Plusbog.dk

For the last ten years, face biometric research has been intensively studied by the computer vision community. Face recognition systems have been used in mobile, banking, and surveillance systems. For face recognition systems, face spoofing attack detection is a crucial stage that could cause severe security issues in government sectors. Although effective methods for face presentation attack detection have been proposed so far, the problem is still unsolved due to the difficulty in the design of features and methods that can work for new spoofing attacks. In addition, existing datasets for studying the problem are relatively small which hinders the progress in this relevant domain. In order to attract researchers to this important field and push the boundaries of the state of the art on face anti-spoofing detection, we organized the Face Spoofing Attack Workshop and Competition at CVPR 2019, an event part of the ChaLearn Looking at People Series. As part of this event, we released the largest multi-modal face anti-spoofing dataset so far, the CASIA-SURF benchmark. The workshop reunited many researchers from around the world and the challenge attracted more than 300 teams. Some of the novel methodologies proposed in the context of the challenge achieved state-of-the-art performance. In this manuscript, we provide a comprehensive review on face anti-spoofing techniques presented in this joint event and point out directions for future research on the face anti-spoofing field.

DKK 290.00
1

The A-Z of the PhD Trajectory - Eva O. L. Lantsoght - Bog - Springer International Publishing AG - Plusbog.dk

Potential Functions of Random Walks in Z with Infinite Variance - Kohei Uchiyama - Bog - Springer International Publishing AG - Plusbog.dk

Potential Functions of Random Walks in Z with Infinite Variance - Kohei Uchiyama - Bog - Springer International Publishing AG - Plusbog.dk

This book studies the potential functions of one-dimensional recurrent random walks on the lattice of integers with step distribution of infinite variance. The central focus is on obtaining reasonably nice estimates of the potential function. These estimates are then applied to various situations, yielding precise asymptotic results on, among other things, hitting probabilities of finite sets, overshoot distributions, Green functions on long finite intervals and the half-line, and absorption probabilities of two-sided exit problems. The potential function of a random walk is a central object in fluctuation theory. If the variance of the step distribution is finite, the potential function has a simple asymptotic form, which enables the theory of recurrent random walks to be described in a unified way with rather explicit formulae. On the other hand, if the variance is infinite, the potential function behaves in a wide range of ways depending on the step distribution, which the asymptotic behaviour of many functionals of the random walk closely reflects. In the case when the step distribution is attracted to a strictly stable law, aspects of the random walk have been intensively studied and remarkable results have been established by many authors. However, these results generally do not involve the potential function, and important questions still need to be answered. In the case where the random walk is relatively stable, or if one tail of the step distribution is negligible in comparison to the other on average, there has been much less work. Some of these unsettled problems have scarcely been addressed in the last half-century. As revealed in this treatise, the potential function often turns out to play a significant role in their resolution. Aimed at advanced graduate students specialising in probability theory, this book will also be of interest to researchers and engineers working with random walks and stochastic systems.

DKK 519.00
1

International Conference on Applied Technologies - - Bog - Springer International Publishing AG - Plusbog.dk

International Conference on Applied Technologies - - Bog - Springer International Publishing AG - Plusbog.dk

International Conference on Applied Technologies - - Bog - Springer International Publishing AG - Plusbog.dk

Inverters and AC Drives - Narayanaswamy P.r. Iyer - Bog - Springer International Publishing AG - Plusbog.dk

Principles of Signals and Systems - Orhan Gazi - Bog - Springer International Publishing AG - Plusbog.dk

Applied Multivariate Statistical Analysis - Wolfgang Karl Hardle - Bog - Springer International Publishing AG - Plusbog.dk

DSP for MATLAB and LabVIEW III - Forester W. Isen - Bog - Springer International Publishing AG - Plusbog.dk

DSP for MATLAB and LabVIEW III - Forester W. Isen - Bog - Springer International Publishing AG - Plusbog.dk

This book is Volume III of the series DSP for MATLAB™ and LabVIEW™. Volume III covers digital filter design, including the specific topics of FIR design via windowed-ideal-lowpass filter, FIR highpass, bandpass, and bandstop filter design from windowed-ideal lowpass filters, FIR design using the transition-band-optimized Frequency Sampling technique (implemented by Inverse-DFT or Cosine/Sine Summation Formulas), design of equiripple FIRs of all standard types including Hilbert Transformers and Differentiators via the Remez Exchange Algorithm, design of Butterworth, Chebyshev (Types I and II), and Elliptic analog prototype lowpass filters, conversion of analog lowpass prototype filters to highpass, bandpass, and bandstop filters, and conversion of analog filters to digital filters using the Impulse Invariance and Bilinear Transform techniques. Certain filter topologies specific to FIRs are also discussed, as are two simple FIR types, the Comb and Moving Average filters. The entire series consists of four volumes that collectively cover basic digital signal processing in a practical and accessible manner, but which nonetheless include all essential foundation mathematics. As the series title implies, the scripts (of which there are more than 200) described in the text and supplied in code form here will run on both MATLAB™ and LabVIEW™. The text for all volumes contains many examples, and many useful computational scripts, augmented by demonstration scripts and LabVIEW™ Virtual Instruments (VIs) that can be run to illustrate various signal processing concepts graphically on the user's computer screen. Volume I consists of four chapters that collectively set forth a brief overview of the field of digital signal processing, useful signals and concepts (including convolution, recursion, difference equations, LTI systems, etc), conversion from the continuous to discrete domain and back (i.e., analog-to-digital and digital-to-analog conversion), aliasing, the Nyquist rate, normalized frequency, sample rate conversion and Mu-law compression, and signal processing principles including correlation, the correlation sequence, the Real DFT, correlation by convolution, matched filtering, simple FIR filters, and simple IIR filters. Chapter four of Volume I, in particular, provides an intuitive or ""first principle"" understanding of how digital filtering and frequency transforms work. Volume II provides detailed coverage of discrete frequency transforms, including a brief overview of common frequency transforms, both discrete and continuous, followed by detailed treatments of the Discrete Time Fourier Transform (DTFT), the z-Transform (including definition and properties, the inverse z-transform, frequency response via z-transform, and alternate filter realization topologies including Direct Form, Direct Form Transposed, Cascade Form, Parallel Form, and Lattice Form), and the Discrete Fourier Transform (DFT) (including Discrete Fourier Series, the DFT-IDFT pair, DFT of common signals, bin width, sampling duration, and sample rate, the FFT, the Goertzel Algorithm, Linear, Periodic, and Circular convolution, DFT Leakage, and computation of the Inverse DFT). Volume IV, the culmination of the series, is an introductory treatment of LMS Adaptive Filtering and applications, and covers cost functions, performance surfaces, coefficient perturbation to estimate the gradient, the LMS algorithm, response of the LMS algorithm to narrow-band signals, and various topologies such as ANC (Active Noise Cancelling) or system modeling, Periodic Signal Removal/Prediction/Adaptive Line Enhancement (ALE), Interference Cancellation, Echo Cancellation (with single- and dual-H topologies), and Inverse Filtering/Deconvolution/Equalization. Table of Contents: Principles

DKK 426.00
1