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Quantitative Evaluation Of Diffusion-Weighted Imaging Techniques For The Purposes Of Radiotherapy Planning In The Prostate, Gary P. Liney, Lois C. Holloway, T M. Al Harthi, Mark Sidhom, D Moses, E Juresic, Roshika Rai, David J. Manton
Quantitative Evaluation Of Diffusion-Weighted Imaging Techniques For The Purposes Of Radiotherapy Planning In The Prostate, Gary P. Liney, Lois C. Holloway, T M. Al Harthi, Mark Sidhom, D Moses, E Juresic, Roshika Rai, David J. Manton
Faculty of Engineering and Information Sciences - Papers: Part A
Objective: Diffusion-weighted imaging (DWI) is an important technique for the localization of prostate cancer, and its response assessment during treatment with radiotherapy (RT). However, it has known limitations in terms of distortions and artefacts using standard acquisition techniques. This study evaluates two alternative methods that offer the promise of improved image quality and the potential for more reliable and consistent diffusion data. Methods: Three DWI techniques were investigated; singleshot echoplanar imaging (EPI), EPI combined with reduced volume excitation (ZOOMit; Siemens Healthcare, Erlangen, Germany) and read-out segmentation with navigator-echo correction (RESOLVE; Siemens Healthcare). Daily measurements of apparent diffusion coefficient (ADC) value …
Mixed Quadratic-Cubic Autocatalytic Reaction-Diffusion Equations: Semi-Analytical Solutions, Muteb Alharthi, Timothy Marchant, Mark Nelson
Mixed Quadratic-Cubic Autocatalytic Reaction-Diffusion Equations: Semi-Analytical Solutions, Muteb Alharthi, Timothy Marchant, Mark Nelson
Faculty of Engineering and Information Sciences - Papers: Part A
Semi-analytical solutions for autocatalytic reactions with mixed quadratic and cubic terms are considered. The kinetic model is combined with diffusion and considered in a onedimensional reactor. The spatial structure of the reactant and autocatalyst concentrations are approximated by trial functions and averaging is used to obtain a lower-order ordinary differential equation model, as an approximation to the governing partial differential equations. This allows semi-analytical results to be obtained for the reaction–diffusion cell, using theoretical methods developed for ordinary differential equations. Singularity theory is used to investigate the static multiplicity of the system and obtain a parameter map, in which the …
Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong
Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong
Faculty of Engineering and Information Sciences - Papers: Part A
The objective of this study is to develop a hot diffusion-compression bonding process for cladding low carbon steel (LCS) to high chromium cast iron (HCCI) in solid-state. The influence of temperature (950-1150 degrees C) and strain rate (0.001-1 s (1)) on microstructure, hardness and bond strength of the HCCI/LCS bimetal were investigated. The interface microstructure reveals that the unbonded region can only be found for 950 degrees C due to lack of diffusion, while the intergrowth between the constituent metals occurred at and above 1100 degrees C. When bonding temperature increases to 1150 degrees C, a carbide-free zone was observed …
Espi Filtering Method Based On Anisotropic Coherence Diffusion And Perona-Malik Diffusion, Zhitao Xiao, Zhenbei Xu, Fang Zhang, Lei Geng, Jun Wu, Quan Yuan, Jiangtao Xi
Espi Filtering Method Based On Anisotropic Coherence Diffusion And Perona-Malik Diffusion, Zhitao Xiao, Zhenbei Xu, Fang Zhang, Lei Geng, Jun Wu, Quan Yuan, Jiangtao Xi
Faculty of Engineering and Information Sciences - Papers: Part A
Noise reduction is one of the most important concerns in electronic speckle pattern interferometry (ESPI). According to partial differential equation (PDE) filtering theory, we present an anisotropic PDE noise- reduction model based on fringe structure information for interferometric fringe patterns. This model is based on coherence diffusion and Perona-Malik (P-M) diffusion. The former can protect the structure information of fringe pattern, while the latter can effectively filter off the noise inside the fringes. The proposed model generated by the two diffusion methods helps to obtain good effects of denoising and fidelity. ESPI fringes and the phase pattern are tested. Experimental …
On The Curve Diffusion Flow Of Closed Plane Curves, Glen Wheeler
On The Curve Diffusion Flow Of Closed Plane Curves, Glen Wheeler
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we consider the steepest descent H−1-gradient flow of the length functional for immersed plane curves, known as the curve diffusion flow. It is known that under this flow there exist both initially immersed curves that develop at least one singularity in finite time and initially embedded curves that self-intersect in finite time. We prove that under the flow closed curves with initial data close to a round circle in the sense of normalised L2 oscillation of curvature exist for all time and converge exponentially fast to a round circle. This implies that for a sufficiently large ‘waiting …
A Novel Method Of Embedding Additional Information Into Tensor Diffusion Filtering As An Application For Multi-Modal Reconstruction In Et, D Kazantsev, Sebastien Ourselin, Brian F. Hutton, W. R B. Lionheart, Simon Arridge
A Novel Method Of Embedding Additional Information Into Tensor Diffusion Filtering As An Application For Multi-Modal Reconstruction In Et, D Kazantsev, Sebastien Ourselin, Brian F. Hutton, W. R B. Lionheart, Simon Arridge
Faculty of Engineering and Information Sciences - Papers: Part A
The fast development of hybrid imaging modalities in tomography, such as SPECT (single photon emission computed tomography)/CT (computed tomography), PET (positron emission tomography)/MRI (magnetic resonance imaging) and PET/CT, have increased an interest for reconstruction algorithms which are able to utilize a functional and anatomical information at the same time. In this paper a new method proposed for iterative reconstruction with anatomical prior in emission tomography (ET). The introduced regularization term is a modified anisotropic tensor diffusion filter which has shape-adapted smoothing properties. The filter accommodates available anatomical information which results in enhanced position and image dependent spatial resolution of emission …
Semi-Analytical Solutions For Cubic Autocatalytic Reaction-Diffusion Equations; The Effect Of A Precursor Chemical, Muteb Alharthi, Timothy Marchant, Mark Nelson
Semi-Analytical Solutions For Cubic Autocatalytic Reaction-Diffusion Equations; The Effect Of A Precursor Chemical, Muteb Alharthi, Timothy Marchant, Mark Nelson
Faculty of Engineering and Information Sciences - Papers: Part A
Semi-analytical solutions for a cubic autocatalytic reaction, with linear decay and a precursor chemical, are considered. The model is coupled with diffusion and considered in a one-dimensional reactor. In this model the reactant is supplied by two mechanisms, diffusion via the cell boundaries and decay of an abundant precursor chemical present in the reactor. The Galerkin method is used to approximate the spatial structure of the reactant and autocatalyst concentrations in the reactor. Ordinary differential equations are then obtained as an approximation to the governing partial differential equations and analyzed to obtain semi-analytical results for the reaction-diffusion cell. Singularity theory …
The Diffusion Of Rfid Implants For Access Control And Epayments: A Case Study On Baja Beach Club In Barcelona, Katina Michael, M G. Michael
The Diffusion Of Rfid Implants For Access Control And Epayments: A Case Study On Baja Beach Club In Barcelona, Katina Michael, M G. Michael
Faculty of Engineering and Information Sciences - Papers: Part A
RFID implants for humans have been used in a variety of contexts since their commercial inception in 2003. The VeriChip product which typically carries a 16 digit number was first marketed as an identification device in the ehealth space (e.g. for emergency response), then as an access control mechanism (e.g. security), and finally as an epayment solution (e.g. the purchase of drinks at clubs). This paper investigates the story behind RFID implants for club patronage access control and epayment. The study uses a two-fold qualitative approach in the collection of data for the single case study of the Baja Beach …
Estimation Of Diffusion Coefficients, Lateral Shear Stress, And Velocity In Open Channels With Complex Geometry, Shu-Qing Yang, Jian-Xing Yu, Yuan-Zhan Wang
Estimation Of Diffusion Coefficients, Lateral Shear Stress, And Velocity In Open Channels With Complex Geometry, Shu-Qing Yang, Jian-Xing Yu, Yuan-Zhan Wang
Faculty of Engineering and Information Sciences - Papers: Part A
The lateral distributions of depth-averaged apparent shear stress, depth mean velocity, and diffusion coefficients are essential in certain quantitative analysis for sediment transport and environmental studies. An analytical method for the computation of these parameters is presented. A mathematical relationship between these parameters, based on the concept of surplus energy transport through a minimum relative distance developed by Yang and Lim [1997], is established, the depth-averaged apparent shear stress is determined from the boundary shear stress, depth mean velocity is obtained by considering the influence of nonuniform shear velocity and the free surface in 3-D channels, and the diffusion coefficients …