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Overall heat transfer coefficient (U) and fluid to particle heat transfer coefficient (h$ sb{ rm fp}$) in canned liquid/particle mixtures, subjected to end-over-end processing, were experimentally evaluated. A methodology was developed to measure heat transfer coefficients, while allowing the movement of the particle inside the can, by attaching it to a flexible fine wire thermocouple. Heat transfer coefficients were evaluated under two conditions: (1) with a single particle in the can, (2) with multiple particles in the can. / In the single particle experiments, a spherical particle was used to evaluate the influence of system parameters and product parameters on associated U and h$ sb{ rm fp}$. Increasing values of all four system variables improved the heat transfer coefficients. The effects of rotational speed and headspace were most significant. The particle density had no significant effect, but liquid viscosity and rotational speed had significant effects on U. The h$ sb{ rm fp}$ values were influenced by rotational speed, liquid viscosity and particle density, with particle density most significant. / With multiple particles (Nylon) in cans, the associated convective heat transfer coefficients (U and h$ sb{ rm fp}$) were evaluated. Heat transfer coefficients increased with decreasing particle diameter, increasing particle concentration and increasing sphericity. / Flow visualization studies were carried out. With a single particle, liquid viscosity, particle density and rotational speed influenced particle motion. With multiple particles, motion/mixing was influenced by particle concentration, size, and shape, liquid viscosity and rotational speed. / Dimensionless correlations were developed for the predictive modeling of convective heat transfer coefficients. For U with a single particle, Nusselt number (Nu) was correlated to Reynolds number (Re), Prandtl number (Pr) and relative can headspace while with multiple particles, Re, Pr, ratio of particle to liquid concentration, relative particle diameter and particle sphericity were found to be significant. For h$ sb{ rm fp}$ with a single particle in the can, three different correlations, one each for a sphere, a cylinder and a cube were developed and the Nu was correlated to Re, Pr, density simplex, relative can headspace and the ratio of the sum of the diameter of rotation and diameter of the can to the can diameter. With multiple particles Nu was correlated to Re or Peclet number, ratio of particle to liquid thermal conductivity, particle to liquid concentration and particle sphericity. / A multi-layer artificial neural network (ANN) was used to model heat transfer parameters under conduction and convection heating conditions. The network was found to predict optimal sterilization temperatures with an accuracy of $ pm$0.5$ sp circ$C, and other responses such as process time and integrated heating time for quality attribute with less than 5% associated errors. Multi-layer neural network models were trained based on the experimental values of U and h$ sb{ rm fp}$, was obtained. The trained network was found to predict U and h$ sb{ rm fp}$ with less than 3% and 5% errors, respectively. The neural network models were more accurate than the dimensionless number models, for predicting U and h$ sb{ rm fp}$. (Abstract shortened by UMI.)

Non-Uniform Rational B-Splines (NURBS) curve has acquired great significance in the field of Computer Aided Design and Machining due to their ability to draw a large variety of shapes in an interactive computer graphics environment. A biarc curve is a composition of two circular arcs such that they are tangent continuous at the point of join. Biarcs have replaced traditionally used line segments in approximating curves and surfaces for generating tool paths of Computerised cutting machines called CNC (Computerised Numerical Controlled) machines. This is due to their ability to be at a greater proximity to the original curve with fewer number of segments. Since most of the machining tools can move only in straight lines and circular arcs, it is desirable that the tool paths be composed of biarcs and/or straight line segments. Shape preserving interpolation is a technique of drawing a curve through a set of points such that the shape represented by the data points are preserved. Both NURBS and biarc curves are not essentially shape preserving curves; however, if certain constraints are imposed on them, they are able to preserve the shape represented by the data points. This work proposes a technique that incorporates both NURBS and biarcs to perform the interpolation. The advantages are twofold; it acts as a common platform for the two techniques to operate together, which is novel, and the fitted NURBS curve can be approximated by biarcs, which has applications in the machining industry.

Vehicle-to-grid (V2G) network, which provides electricity charging service to the electric vehicles (EVs), is an essential part of the smart grid (SG). It can not only effectively reduce the greenhouse gas emission but also significantly enhance the efficiency of the power grid. Due to the limitation of the local electricity resource, the quality of charging service can be hardly guaranteed for every EV in V2G network. To this end, the multi-quality charging is introduced to provide quality-guaranteed service (QGS) to the qualified EVs and best effort service (BES) to the other EVs. To perform the multi-quality charging, the evaluation on the EV's attributes is necessary to determine which level of charging service can be offered to the EV. However, the EV owner's privacy such as real identity, lifestyle, location, and sensitive information in the attributes may be violated during the evaluation and authentication. In this thesis, a privacy-preserving multi-quality charging (PMQC) scheme for V2G network is proposed to evaluate the EV's attributes, authenticate its service eligibility and generate its bill without revealing the EV's private information. Specifically, by adopting ciphertext-policy attribute based encryption (CP-ABE), the EV can be evaluated to have proper charging service without disclosing its attribute privacy. By utilizing group signature, the EV's real identity is kept confidential during the authentication and the bill generation. By hiding the EV's real identity, the EV owner's lifestyle privacy and location privacy are also preserved. Security analysis demonstrates that PMQC can achieve the EV's privacy preservation, fine-grained access control on the EVs for QGS, traceability of the EV's real identity and secure revocation on the EV's service eligibility. Performance evaluation result shows that PMQC can achieve higher efficiency in authentication and verification compared with other schemes in terms of computation overhead. Based on PMQC, the EV's computation overhead and storage overhead can be further reduced in the extended privacy-preserving multi-quality charging (ePMQC) scheme.

Non-Uniform Rational B-Splines (NURBS) curve has acquired great significance in the field of Computer Aided Design and Machining due to their ability to draw a large variety of shapes in an interactive computer graphics environment. A biarc curve is a composition of two circular arcs such that they are tangent continuous at the point of join. Biarcs have replaced traditionally used line segments in approximating curves and surfaces for generating tool paths of Computerised cutting machines called CNC (Computerised Numerical Controlled) machines. This is due to their ability to be at a greater proximity to the original curve with fewer number of segments. Since most of the machining tools can move only in straight lines and circular arcs, it is desirable that the tool paths be composed of biarcs and/or straight line segments. Shape preserving interpolation is a technique of drawing a curve through a set of points such that the shape represented by the data points are preserved. Both NURBS and biarc curves are not essentially shape preserving curves; however, if certain constraints are imposed on them, they are able to preserve the shape represented by the data points. This work proposes a technique that incorporates both NURBS and biarcs to perform the interpolation. The advantages are twofold; it acts as a common platform for the two techniques to operate together, which is novel, and the fitted NURBS curve can be approximated by biarcs, which has applications in the machining industry.

Graduation date: 1949

Graduation date: 1938

Graduation date: 1942

Graduation date: 1944

Graduation date: 1953