Introduction 1-2 Definition of a Fluid Fluid mechanics: the behavior of The solid object will no change fluids at rest and in motion inside the a closed container A fluid is a substance that deforms continuously under the application The liquid will change its shape of a shear(tangential) stress no to conform to that of the matter how small the shear stress container and will take on the may be

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Introduction The nervous tissue of animals responds to stimuli within and outside of the body. Incoming information is integrated and a response is made. The response is muscle contraction or secretion by a gland. The end hydra result is the maintenance of body functions or homeostasis

Introduction (chapter objectives) Power spectral density Matched filters Recall former Chapter that random signals are used to convey information. Noise is also described in terms of statistics. Thus, knowledge of random signals and noise is fundamental to an understanding of communication systems

Introduction (chapter objectives) Complex envelopes and modulated signals Spectra of bandpass signals Nonlinear distortion · Communication circuits(mixers, phase- locked loops, frequency synthesizers, and detectors) Transmitters and receivers · Software radios

Introduction Basic signal properties(dc, rms, dBm, and power) Fourier transform and spectra Linear systems and linear distortion Bandlimited signal and sampling Discrete Fourier transform Bandwidth of signal

Introduction Frequency-selective fading is a dominant impairment in mobile communications Fading reduces receive signal-to-noise ratio and degrades the bit-error-rate(BER) Frequency selectivity of the channel, i. e, delay spread, induces inter-symbol interference(ISI) To combat frequency-selective fading

概述(introduction): Factors cause diseases chemicals physical biologicalpsychological chemicals: occupational, non- occupational. physical: occupational, non- occupational

Upper respiratory tract Lower Respiratory tract Terminal respiratory Unite(anatomy of the Acinus) Circulation of the Lung www.zshospital.com

Lecture 1 Introduction and classification of geometric modeling forms 1.1 Motivation Geometric modeling deals with the mathematical representation of curves, surfaces, and solids necessary in the definition of complex physical or engineering objects. The associated field of computational geometry is concerned with the development, analysis, and computer implemen tation of algorithms encountered in geometric modeling. The objects we are concerned with in engineering range from the simple