Ultrasound imaging is considered one of the most powerful techniques for medical diagnosis and is often preferred over other medical imaging modalities because of noninvasive, portable, versatile and low-cost properties (Webb, 2002; Abd-Elmoniem, 2002; Porter, 2001; Shekhar, 2002). A fundamental problem in the field of ultrasound imaging is the speckle noise influence, which is a major limitation on image quality inultrasound imaging.
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Leupeptin reduces impulse noise induced hearing loss
Journal of Occupational Medicine and Toxicology 2011, 6:38 doi:10.1186/1745-6673-6-38
Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Impacts of impulsive noise from partial discharges on wireless systems performance: application to MIMO precoders
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Detail-Preserving Restoration of Impulse Noise Corrupted Images by a Switching Median Filter Guided by a Simple Neuro-Fuzzy Network
NOISE AND DISTORTION
2.1 Introduction 2.2 White Noise 2.3 Coloured Noise 2.4 Impulsive Noise 2.5 Transient Noise Pulses 2.6 2.7 2.8 2.9 2.10 Thermal Noise Shot Noise Electromagnetic Noise Channel Distortions Modelling Noise
oise can be defined as an unwanted signal that interferes with the communication or measurement of another signal. A noise itself is a signal that conveys information regarding the source of the noise. For example, the noise from a car engine conveys information regarding the state of the engine.
10.1 10.2 10.3 10.4 Introduction Polynomial Interpolation Model-Based Interpolation Summary
nterpolation is the estimation of the unknown, or the lost, samples of a signal using a weighted average of a number of known samples at the neighbourhood points. Interpolators are used in various forms in most signal processing and decision making systems.
12.1 12.2 12.3 12.4 12.5 12.6 12.7 Impulsive Noise Statistical Models for Impulsive Noise Median Filters Impulsive Noise Removal Using Linear Prediction Models Robust Parameter Estimation Restoration of Archived Gramophone Records Summary
mpulsive noise consists of relatively short duration “on/off” noise pulses, caused by a variety of sources, such as switching noise, adverse channel environments in a communication system, dropouts or surface degradation of audio recordings, clicks from computer keyboards, etc.
TRANSIENT NOISE PULSES
13.1 Transient Noise Waveforms 13.2 Transient Noise Pulse Models 13.3 Detection of Noise Pulses 13.4 Removal of Noise Pulse Distortions
ransient noise pulses differ from the short-duration impulsive noise studied in the previous chapter, in that they have a longer duration and a relatively higher proportion of low-frequency energy content, and usually occur less frequently than impulsive noise. The sources of transient noise pulses are varied, and may be electromagnetic, acoustic or due to physical defects in the recording medium.
LINEAR PREDICTION MODELS
Linear Prediction Coding Forward, Backward and Lattice Predictors Short-term and Long-Term Linear Predictors MAP Estimation of Predictor Coefficients Sub-Band Linear Prediction Signal Restoration Using Linear Prediction Models Summary
inear prediction modelling is used in a diverse area of applications, such as data forecasting, speech coding, video coding, speech recognition, model-based spectral analysis, model-based interpolation, signal restoration, and impulse/step event detection.
This book provides an insight for students, researchers and practitioners on the area of vehicular communications explaining and presenting solutions for some of the most critical issues in this field and, hopefully, inspiring new research directions. The book is organized in Sections, which respond to different layers and aspects of the vehicular technology: infrastructures, cells deployment and its integration with the V2V part, access procedures, advanced services and applications as localization, spectrum sensing, relay-based cooperative networks....
Voice channel occupies the band from 300 to 3400 Hz.
Some frequencies are attenuated more than others.
Velocity of propagation varies with frequency.
Filter: increase toward band center and decrease toward band edge.
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Channel Impulse Response Length and Noise Variance Estimation for OFDM Systems with Adaptive Guard Interval
Digital Image Processing: Image Restoration - Duong Anh Duc includes Image Restoration; Restoration vs. Enhancement; Degradation Model; Gaussian noise; Erlang(Gama) noise; Exponential noise; Impulse (salt-and-pepper) noise; Plot of density function of different noise models.
High data rate communications are limited not only by noise, --butespecially with increas(ISI) ing symbolrates -often more significantly by the Inter Symbol Interference due to the memory of the dispersive wireless communications channel . Explicitly, this channel memory is caused by the dispersive channel impulse response (CIR) due to the differentlength propagation paths between the transmitting and the receiving antennae. This dispersion effect could theoretically be measured by transmitting an infinitely short impulse and “receiving” the CIR itself....