In order to improve manufacturing quality and ensure public safety, components and structures are commonly inspected for early detection of defects or faults which may reduce their structural integrity. Non Destructive Testing (NDT) and Evaluation (NDE) techniques present the advantages of leaving the specimens undamaged after the inspection. NDT involves treating defect detection and character...

algorithms, the geometrical properties such as size, shape, and orientation, of objects can also be investigated by ultrasonic imaging methods. An inherent problem with ultrasonic detection is the conflict between signal-to-noise ratio and resolution. If good resolution is to be obtained, the transmitted pulse cannot be long in duration. If short ultrasonic pulses are used, their energy is smal...

Feature extraction is a collection of the necessary detailed information from given source, which holds for further analysis. The quality fused image depends on many parameters, particularly its directional selectivity and shift-invariance. On other hand, traditional wavelet-based transforms produce ringing distortions artifacts due to poor directionality shift invariance. Dual-Tree Complex Wav...

Recent wavelet research has primarily focused on real-valued wavelet bases. However, the complex filterbanks provide much convenience for complex signal processing. For example, in radar and sonar signal processing, the complex signals from the receiver can be efficiently processed with complex filterbanks rather than real filterbanks. Specifically, the positive and negative Doppler frequencies...

The propagation of optical pulses in a single mode fiber is analyzed by solving nonlinear Schrödinger (NLS) equation numerically. The propagation is modeled using a split-step wavelet method, analogous to the split-step Fourier method, while retaining the advantages of the wavelet transform. Pulses and pulse sequences are accommodated with equal ease, as is frequency chirping of the light sourc...

Applications, which need to store large database and/or transmit digital images requiring high bit-rates over channels with limited bandwidth, have demanded improved image compression techniques. This paper describes practical and effective image compression system based on neuro-fuzzy model which combines the advantages of fuzzy vector quantization with neural network and wavelet transform. Th...

Polymer Bonded Explosives (PBX) are well-known explosives for the weapons, especially for the parts of some important weapon. Generally, they first are modelled in cylinder. One of the most important issues in PBX cylinder properties is the detection of its flaw. Each PBX cylinder may have flaws that influence the security, machine-performance and other important physical or chemical performanc...