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Full-Text Articles in Physics

Ultrafast Nonlinear Transparency Driven At A Telecom Wavelength In An Organic Semiconductor System, Joong-Mok Park, Di Cheng, Aaron Patz, Liang Luo, Fadzai Fungura, Ruth Shinar, Kai-Ming Ho, Joseph Shinar, Jigang Wang Feb 2019

Ultrafast Nonlinear Transparency Driven At A Telecom Wavelength In An Organic Semiconductor System, Joong-Mok Park, Di Cheng, Aaron Patz, Liang Luo, Fadzai Fungura, Ruth Shinar, Kai-Ming Ho, Joseph Shinar, Jigang Wang

Ames Laboratory Accepted Manuscripts

Ultrafast laser-induced transparency is demonstrated using femtosecond (fs) pump-probe experiments in the organic P3HT:PCBM (donor:acceptor) blend structure. For above band gap pumping, ultrafast transient signals strongly depend on the probe photon energy. Most intriguingly, for below band gap pumping at 0.95 eV, or 1.3 µm at a telecom wavelength, a huge transmission increase up to 30% only during the laser pulse ∼100 fs is observed as a pump-driven, quasi-instantaneous suppression of absorption for the high photon-energy energy probe beam. We attribute the observed laser-driven transparency to dynamic Franz-Keldysh effect, at least one order of magnitude stronger ...


Biodetection And Biointerface Based On Nanostructured Aluminum Oxide (Nao): From Fluorescence Enhancement To Ms Effect On Single Neural Cells, Xiangchen Che Jan 2018

Biodetection And Biointerface Based On Nanostructured Aluminum Oxide (Nao): From Fluorescence Enhancement To Ms Effect On Single Neural Cells, Xiangchen Che

Graduate Theses and Dissertations

Anodic aluminum oxide (AAO) has been investigated and utilized in numerous products for almost a century. But the rapidly increasing interest in nanoscale materials and their outstanding properties has propelled nanoporous AAO to be used as a substrate for sensors and biosensors. Fluorescence-based biosensors are one type of optical biosensors which are very popular for detecting a variety of targets (DNA, RNA, glucose, enzyme, bacteria, etc.). The recent discovery of AAO fluorescence enhancement effect makes AAO more attractive since it has the great potential to be used in biosensing field to improve the sensor sensitivity. However, the mechanism of the ...


Periodically Patterned Structures For Nanoplasmonic And Biomedical Applications, Akshit Peer Jan 2017

Periodically Patterned Structures For Nanoplasmonic And Biomedical Applications, Akshit Peer

Graduate Theses and Dissertations

Periodically patterned nanostructures have imparted profound impact on diverse scientific disciplines. In physics, chemistry, and materials science, artificially engineered photonic crystals have demonstrated an unprecedented ability to control the propagation of photons through light concentration and diffraction. The field of photonic crystals has led to many technical advances in fabricating periodically patterned nanostructures in dielectric/metallic materials and controlling the light-matter interactions at the nanoscale. In the field of biomaterials, it is of great interest to apply our knowledge base of photonic materials and explore how such periodically patterned structures control diverse biological functions by varying the available surface area ...


Novel Biomarker Assays Based On Photothermal Effects And Nanophotonics, Yunfei Zhao Jan 2017

Novel Biomarker Assays Based On Photothermal Effects And Nanophotonics, Yunfei Zhao

Graduate Theses and Dissertations

The early diagnosis of some chronic and severe diseases such as cancer, tuberculosis, etc. has been a long-sought goal of the medicine community. Traditional diagnostic tools such as X-ray and fecal blood tests cannot detect the disease before the focus or tumor have grown to an appreciable size or before the number of pathogens or tumor cells has reached a considerable amount in body fluids. These drawbacks could significantly delay the diagnosis. To detect and diagnose such diseases at an early stage, people have sought to detect the biomarkers related to certain physical conditions so that the anomalies caused by ...


Organic Solar Cells: Degradation Processes And Approaches To Enhance Performance, Fadzai Fungura Jan 2016

Organic Solar Cells: Degradation Processes And Approaches To Enhance Performance, Fadzai Fungura

Graduate Theses and Dissertations

Organic solar cells (OSCs) have attracted a lot of attention due to their potential as flexible, lightweight, and low-cost renewable energy sources. Significant improvements have been made in increasing the devices’ power conversion efficiency (PCE) and extensive efforts to understand degradation mechanisms and increase OSCs’ lifetimes are ongoing. OSCs with higher than 10% efficiency have been reported. Enhanced stability and efficiency of inverted poly(3-hexylthiophene) (P3HT) solar cells with Cesium (Cs) halides were achieved by spin-coating Bphen (4,7-di(phenyl)-1,10-phenanthroline) on the halide layer and adding an ~100nm polystyrene beads layer on the blank side of the OSC ...


Electric Potential And Electric Field Imaging With Applications, E. R. Generazio Jan 2016

Electric Potential And Electric Field Imaging With Applications, E. R. Generazio

Review of Progress in Quantitative Nondestructive Evaluation

The technology and techniques for remote quantitative imaging of electrostatic potentials and electrostatic fields in and around objects and in free space is presented. Electric field imaging (EFI) technology may be applied to characterize intrinsic or existing electric potentials and electric fields, or an externally generated electrostatic field may be used for “illuminating” volumes to be inspected with EFI. The baseline sensor technology, electric field sensor (e-sensor), and its construction, optional electric field generation (quasi-static generator), and current e-sensor enhancements (ephemeral e-sensor) are discussed. Demonstrations for structural, electronic, human, and memory applications are shown. This new EFI capability is demonstrated ...


Elastic Wave Fields Generated By Shear Horizontal Piezoelectric Fiber Patch (Sh-Pfp) Transducers: Parameter Study By Modelling And Laser Vibrometric Measurements, Bernd Köhler, Tobias Gaul, Frank Schubert, Uwe Lieske Jan 2016

Elastic Wave Fields Generated By Shear Horizontal Piezoelectric Fiber Patch (Sh-Pfp) Transducers: Parameter Study By Modelling And Laser Vibrometric Measurements, Bernd Köhler, Tobias Gaul, Frank Schubert, Uwe Lieske

Review of Progress in Quantitative Nondestructive Evaluation

Recently, a novel lightweight and thin piezoelectric transducer was proposed [1-3]. It generates in-plane surface tractions and thus shear horizontal elastic waves in both bulk materials and waveguides. The paper describes the principle of operation of this Shear Horizontal Piezoelectric Fiber Patch (SH-PFP). In continuation of the previous work, several variants of the SH-PFP are studied. The generated wavefield is characterized bywavefield snapshots and directivity functions. Both numerical simulation and measurements by 3D Laser Vibrometry are performed and the results are compared, showing a good agreement. We discuss possible further developments of the SH-PFP transducer to allow 1D directivity and ...


Understanding The Photostability Of Perovskite Solar Cell, Pranav Hemanta Joshi Jan 2016

Understanding The Photostability Of Perovskite Solar Cell, Pranav Hemanta Joshi

Graduate Theses and Dissertations

Global climate change and increasing energy demands have led to a greater focus on cheaper photovoltaic energy solutions. Perovskite solar cells and organic solar cells have emerged as promising technologies for alternative cheaper photovoltaics.

Perovskite solar cells have shown unprecedentedly rapid improvement in power conversion efficiency, from 3% in 2009 to more than 21% today. High absorption coefficient, long diffusion lengths, low exciton binding energy, low defect density and easy of fabrication has made perovskites near ideal material for economical and efficient photovoltaics.

However, stability of perovskite and organic solar cells, especially photostability is still not well understood. In this ...


Photonic Molecules For Subwavelength Light Confinement Design And Applications, Aditya Jain Jan 2016

Photonic Molecules For Subwavelength Light Confinement Design And Applications, Aditya Jain

Graduate Theses and Dissertations

Similar to the confinement of an electron in a potential well, photons can be spatially confined inside a high index resonator. This confinement can be used to create efficient strong light matter interaction, all optical logic, single photon generation among many other possibilities, provided the resonators possess a small physical volume and low photon decay rate simultaneously. In this thesis, we present two resonator designs, that are 30 times smaller than the wavelength of light in a single direction and exhibit large quality factors. Thereafter, we proceed with three different applications of these resonators.

First application is to slow down ...


New Developments In Magneto-Optic Interferometric Switching, John William Pritchard Jan 2015

New Developments In Magneto-Optic Interferometric Switching, John William Pritchard

Graduate Theses and Dissertations

In the next few decades, it is likely that high bandwidth wireless and optical technologies will be placed in the spotlight as the dominant avenues for communication all over the world. It is arguable that this is currently the case, and that the expectation for higher data transfer speeds, more secure and reliable transmission, and longer communication range is on an exponential rise. Thus, much effort and emphasis is being put on these technologies to advance as quickly as possible.

For optical systems, the majority of research has been focused on the realization of all-optical transmission, that is, transmission such ...


Study Of Electronic Characteristics Of Heterojunction With Intrinsic Thin-Layer Devices And Defect Density Profile Of Nanocrystalline Silicon Germanium Devices, Watson Paul Mulder Jan 2015

Study Of Electronic Characteristics Of Heterojunction With Intrinsic Thin-Layer Devices And Defect Density Profile Of Nanocrystalline Silicon Germanium Devices, Watson Paul Mulder

Graduate Theses and Dissertations

Heterojunction with Intrinsic Thin-layer (HIT) solar cells are an important photovoltaic technology, recently reaching record power conversion efficiencies. HIT cells hold advantages over the conventional crystalline Si solar cells, such as their fabrication at lower temperatures and their shorter fabrication time. It is important to understand the electronic characteristics and transport properties of HIT cells to continue to improve their efficiencies. The fundamental measurements of a HIT solar cell with an innovative n+/p/p+ structure are presented. We also report on a series of these HIT cells fabricated on wafers with different doping concentrations, observing the relationship between doping ...


Studies Of Solution-Processed Organic Light-Emitting Diodes And Their Materials, Emily Hellerich Jan 2013

Studies Of Solution-Processed Organic Light-Emitting Diodes And Their Materials, Emily Hellerich

Graduate Theses and Dissertations

The wide use of organic light-emitting diodes (OLEDs) is materializing as devices exhibit enhanced performance. Attention has been placed on finding quality solution-processable organic semiconducting materials amenable to low cost processing via solution-based fabrication methods. The high solubility and good film formability intrinsic to polymers have led to their use in the majority of solution-processed devices. Recently, attention has shifted to the incorporation of small molecules into solution-processed devices. With this focus, we gain the high efficiency of small molecules as well as the ease of fabrication by solution-processing. Research has also been aimed at developing materials with efficient and ...


Non-Metallic Metamaterials: Modelling, Design, And Fabrication Tolerances Analysis, Yang Li Jan 2012

Non-Metallic Metamaterials: Modelling, Design, And Fabrication Tolerances Analysis, Yang Li

Graduate Theses and Dissertations

Metamaterials are artificial materials, consisting of sub-wavelength building blocks, which can show anomalous and exotic electromagnetic responses. Metal-based metamaterials, as the first experimentally implemented metamaterials, have achieved significant progress in theory, fabrication, and characterization over a broad frequency range from microwave to visible. To

alleviate the drawbacks of metal-based metamaterials, such as conductive loss and anisotropy, non-metallic metamaterials have been proposed and developed rapidly in the last decade. This thesis focuses on the analytical modeling and fabrication-tolerance analysis of non-metallic metamaterials consisting of an array of magnetodielectric spheres. Here, the term "magnetodielectric" refers, generally, to materials with relative permittivity and ...


Plasma Surface Interactions In Nanoscale Processing: Preservation Of Low-K Integrity And High-K Gate-Stack Etching With Si Selectivity, Juline Shoeb Jan 2012

Plasma Surface Interactions In Nanoscale Processing: Preservation Of Low-K Integrity And High-K Gate-Stack Etching With Si Selectivity, Juline Shoeb

Graduate Theses and Dissertations

Plasma-surface interactions are very important in the fabrication of the nm-sized features of integrated circuits. Plasma processes are employed to produce high-resolution patterns in many of the thin layers of silicon integrated circuits and to remove masking layers while maintaining high selectivity. Integrated plasma processes consisting of sequential steps such as etch, clean and surface modification, are used in semiconductor industries. The surface in contact with the process plasma is exposed to the fluxes of neutrals, ions, molecules, electrons and photons.

Modeling of surface reaction mechanisms requires the determination of the characterizations of fluxes (e.g. composition, magnitude, energy and ...


Study Of Left-Handed Materials, Jiangfeng Zhou Jan 2008

Study Of Left-Handed Materials, Jiangfeng Zhou

Retrospective Theses and Dissertations

Left handed materials (LHMs) are artificial materials that have negative electrical permittivity, negative magnetic permeability, and negative index of refraction across a common frequency band. They possess electromagnetic (EM) properties not found in nature. LHMs have attracted tremendous attention because of their potential applications to build the perfect lens and cloaking devices. In the past few years there has been ample proof for the existence of LHMs in the microwave frequency range. Recently, researchers are trying hard to push the operating frequency of LHMs into terahertz and the optical regime.;In this thesis, we start with the theoretical prediction of ...


Electromagnetic Materials Characterization Of Ferromagnetic Composites At Microwave Frequencies, Eric Ryan Abram Jan 2007

Electromagnetic Materials Characterization Of Ferromagnetic Composites At Microwave Frequencies, Eric Ryan Abram

Retrospective Theses and Dissertations

No abstract provided.


Theoretical And Experimental Explorations In Atomic Force Microscopy , Anil Gannepalli Jan 2004

Theoretical And Experimental Explorations In Atomic Force Microscopy , Anil Gannepalli

Retrospective Theses and Dissertations

Nanotechnology is the capability to build by controlling the arrangement of individual atoms and molecules. Such a technology would be founded on the ability to control, manipulate and investigate matter at the atomic scale. The invention of atomic force microscope (AFM) and the advances in micro-cantilever based scanning probe technology have significantly enhanced the experimental capability to probe and modify matter at the nanoscale. However, it is still severely limited in achieving the necessary bandwidth, sensitivity and resolution. To further the advances in this field an in-depth understanding of the nature and effects of the tip-sample interactions is imperative. A ...


Using Microwave Doppler Radar In Automated Manufacturing Applications , Gregory C. Smith Jan 2004

Using Microwave Doppler Radar In Automated Manufacturing Applications , Gregory C. Smith

Retrospective Theses and Dissertations

Since the beginning of the Industrial Revolution, manufacturers worldwide have used automation to improve productivity, gain market share, and meet growing or changing consumer demand for manufactured products. To stimulate further industrial productivity, manufacturers need more advanced automation technologies: "smart" part handling systems, automated assembly machines, CNC machine tools, and industrial robots that use new sensor technologies, advanced control systems, and intelligent decision-making algorithms to "see," "hear," "feel," and "think" at the levels needed to handle complex manufacturing tasks without human intervention.;The investigator's dissertation offers three methods that could help make "smart" CNC machine tools and industrial robots ...


Electromechanical Characterization Of Ultrasonic Nde Systems , Changjiu Dang Jan 2001

Electromechanical Characterization Of Ultrasonic Nde Systems , Changjiu Dang

Retrospective Theses and Dissertations

An ultrasonic nondestructive evaluation (NDE) measurement system is a complex collection of many elements such as the pulser/receiver, the cabling, the transducers, and the material configuration being tested. To completely model an ultrasonic measurement system, a system model, called the electroacoustic measurement (EAM) model , was developed. This model allows one to analyze the measurement system at many different levels, ranging from individual details to the entire system itself. The EAM model has been implemented in software using the MATLAB development environment such that one has control over the specification of the detailed system components. On the other hand, the ...


Photonic Bandgap Materials: Design, Fabrication, And Characterization , Ganapathi S. Subramania Jan 2000

Photonic Bandgap Materials: Design, Fabrication, And Characterization , Ganapathi S. Subramania

Retrospective Theses and Dissertations

The last few decades have seen a tremendous explosion in the area of new synthetic materials. As we begin to better understand the nature of the atomic and molecular bonds it has been possible to systematically search for materials with specific properties thanks to the availability of powerful supercomputers. Due to significant advances in materials synthesis a rich variety of artificial materials whose mechanical, chemical, electronic and optical properties can be suitably tailored can now be produced. Some of the materials (plastics, synthetic fibers, ceramics, alloys etc.) can replace or substitute traditional materials; some others have managed to create new ...


Design, Fabrication And Analysis Of A Terfenol-D Based Magnetostrictive External Cavity Diode Laser Sensor With An Advanced Signal Processing Capability , Wing Chiu Chung Jan 1999

Design, Fabrication And Analysis Of A Terfenol-D Based Magnetostrictive External Cavity Diode Laser Sensor With An Advanced Signal Processing Capability , Wing Chiu Chung

Retrospective Theses and Dissertations

Miniature magnetometer is desired in many applications, such as undersea surveillance, buried landmine detection, vehicle tracking and guidance and personal dosimetry. This dissertation reports the fabrication, and characterization of a miniature magnetometer, which utilizes the highly magnetostrictive material, Terfenol-D and an ultra-short external cavity diode laser sensor. A thin slice of the magneto strictive material, biased by an open magnetic circuit, is configured as an external reflector modulating the effective modal reflectivity of the diode laser cavity in response to an ac magnetic field. The detection limit of the sensor are being investigated and the principle of the device is ...


Measurements And Modeling Of The Effects Of An Orthogonal Bias Field On Properties Of Isotropic Magnetic Materials , Ying Bi Jan 1998

Measurements And Modeling Of The Effects Of An Orthogonal Bias Field On Properties Of Isotropic Magnetic Materials , Ying Bi

Retrospective Theses and Dissertations

The effects of the orthogonal bias field were investigated systematically in this study. The measurements on various magnetic materials under different experimental conditions showed that the orthogonal bias field rotated the hysteresis loop reducing permeability and reduced its enclosed area. As a result, permeability, hysteresis loss, coercivity and remanence decreased with increasing orthogonal bias field. The experimental results indicated that the orthogonal field reduced hysteresis loss by increasing the component of reversible domain rotation magnetization;In the present study, the Jiles-Atherton model has been expanded to include the effect of an orthogonal bias field. Based on the experimental observation, a ...


Metallic Photonic Band Gap Structures On Flexible Substrates , Sandhya Gupta Jan 1998

Metallic Photonic Band Gap Structures On Flexible Substrates , Sandhya Gupta

Retrospective Theses and Dissertations

Periodic dielectric and metallic structures have recently generated great interest because they can exhibit a forbidden range of frequency, or a photonic band gap (PBG) where the electromagnetic waves cannot propagate. Since their theoretical prediction in 1987, several applications at frequencies ranging from microwave to optical region have been proposed using these novel structures. This presentation demonstrates the first successful fabrication of flexible metallic PBG structures that show frequency filtering properties at far-infrared frequencies;The metallic PBG filters described here are multi-layered metallic meshes imbedded in a flexible polyimide dielectric. They have a simple, microfabrication-based construction that use alternating dielectric ...


Stability And Electronic Properties Of Amorphous Silicon P-I-N Devices Fabricated Using Ecr Plasma Enhanced Chemical Deposition , Sanjeev Kumar Kaushal Jan 1997

Stability And Electronic Properties Of Amorphous Silicon P-I-N Devices Fabricated Using Ecr Plasma Enhanced Chemical Deposition , Sanjeev Kumar Kaushal

Retrospective Theses and Dissertations

The prime objective of the research was to investigate the fabrication, stability and electronic properties of a-Si:H devices deposited using electron cyclotron resonance (ECR) plasma deposition technique. Both reactive (hydrogen) and non-reactive (helium) gases were used as the primary plasma gas. The reactants generated by the ECR plasma from these gases were allowed to flow towards the substrate, where they reacted with silane to give rise to growth of a-Si:H. In general, we used a high dilution ratio of plasma gas (H2 or He) to silane, about 15:1 to 20:1; for growing a-Si:H. Very high ...


Signal Processing And Image Restoration Techniques For Two-Dimensional Eddy Current Nondestructive Evaluation , Bing Wang Jan 1997

Signal Processing And Image Restoration Techniques For Two-Dimensional Eddy Current Nondestructive Evaluation , Bing Wang

Retrospective Theses and Dissertations

This dissertation presents a comprehensive study on the forward modeling methods, signal processing techniques, and image restoration techniques for two-dimensional eddy current nondestructive evaluation. The basic physical forward method adopted in this study is the volume integral method. We have applied this model to the eddy current modeling problem for half space geometry and thin plate geometry. To reduce the computational complexity of the volume integral method, we have developed a wavelet expansion method which utilizes the multiresolution compression capability of the wavelet basis to greatly reduce the amount of computation with small loss in accuracy. To further improve the ...


Modeling, Characterization And Integration Of Thin Film Resonator Microsensors , Jie Xia Jan 1996

Modeling, Characterization And Integration Of Thin Film Resonator Microsensors , Jie Xia

Retrospective Theses and Dissertations

There is an increasing demand by using smart and miniaturized microsensors and microtransducers in the areas of automobile, environment Science and analytical chemistry. Thin film microresonators (TFRs), meriting from their small size, higher sensitivity and compatibility with VLSI process, have being investigated as microsensors. Gas or vapor absorbed species, or contacted liquids may perturb resonator mechanical, electrical and piezoelectric properties. In this dissertation, a coupled wave theory is presented and applied to analyze acoustic wave propagation phenomena both in TFR-solid and TFR-liquid phases. A two-dimensional analysis is implemented to compare with a one-dimensional model and experimental results. The analysis and ...


Increasing The Efficiency Of A Piezoelectric Aluminum Nitride Microstrip Resonator By Utilizing High Temperature Superconductors , Edward David Goff Jan 1995

Increasing The Efficiency Of A Piezoelectric Aluminum Nitride Microstrip Resonator By Utilizing High Temperature Superconductors , Edward David Goff

Retrospective Theses and Dissertations

High temperature superconductors have potential applications in the field of microwave devices and circuits. To utilize these materials in such a way as to increase the efficiency of these microwave devices would be beneficial for high efficiency/low noise applications. This dissertation accomplishes the following goals: (1) The design and fabrication of an initial device that increases the quality factor, Q, and therefore the efficiency of a high frequency thin film resonator which uses superconducting metal as the device's electrode, (2) the measurement and characterization of this device, (3) the theoretical calculation and predicted performance of this device, and ...


Electronic And Photonic Devices: Experimental Investigations Of Hydrogenated Amorphous Silicon Substrate N+/I/P+ Solar Cell And Fundamental Properties Of Quantum Wells With Cylindrical Geometry And Applications To Electronics And Photonics , Er-Xuan Ping Jan 1995

Electronic And Photonic Devices: Experimental Investigations Of Hydrogenated Amorphous Silicon Substrate N+/I/P+ Solar Cell And Fundamental Properties Of Quantum Wells With Cylindrical Geometry And Applications To Electronics And Photonics , Er-Xuan Ping

Retrospective Theses and Dissertations

This thesis consists of two different parts: (I) experimental investigations of hydrogenated amorphous silicon substrate n[superscript]+/i/p[superscript]+ solar cells and, (II) fundamental properties of quantum wells with cylindrical geometry and applications to electronics and photonics;Part I. The substrate structural n[superscript]+/i/p[superscript]+ solar cells based on a-Si:H materials are fabricated by a radio frequency (RF) triode geometric plasma enhanced chemical vapor deposition (PECVD) system. The solar cells have been electrically and optically tested. Two different substrates, tin-oxide coated glass and stainless steel foil, are used. An RF magnetron sputtering system is used to ...


A Closed-Form Integration Method For State-Space Time-Domain Analysis Of Electronic Circuits And Systems , Bruce Alan Alspaugh Jan 1994

A Closed-Form Integration Method For State-Space Time-Domain Analysis Of Electronic Circuits And Systems , Bruce Alan Alspaugh

Retrospective Theses and Dissertations

While most traditional circuit simulation programs such as SPICE rely upon numerical integration techniques to perform transient analysis, this dissertation presents an alternative approach that relies on closed-form integration. Traditional numerical approaches offer no hope of finding an analytical solution, even if it is known that the solutions will be in a simple functional form. By using closed-form methods, the computer can find the exact analytical solution to the network and completely avoid problems associated with numerical approximations, determining appropriate integration step sizes, stiff systems of differential equations, or accumulated global error. Computer run time is independent of the amount ...


General Automated Flaw Detection Scheme For Nde X-Ray Images, Karl Ulmer, John P. Basart Jan 1993

General Automated Flaw Detection Scheme For Nde X-Ray Images, Karl Ulmer, John P. Basart

Review of Progress in Quantitative Nondestructive Evaluation

This paper presents an approach to automated flaw detection (AFD) in an arbitrary X-ray image. The intensities in the digitized radiographic image are modeled as piecewise-smooth surface functions corrupted by noise and flaws. It has been observed that radiographs generated for NDE purposes containing flaws also have a combination of three unwanted features; background trends, geometrical structures, and noise. These features inhibit the performance of automated flaw detection algorithms. The proposed general processing scheme reduces the unwanted features in such a way that candidate flaws within the image can be identified. The proposed scheme is robust and is applicable to ...