Industrial facilities that plan the shutdown of equipment for service have large financial savings compared to those managing unplanned shutdowns. To this end, a variety of algorithms have been developed and published in the literature that can monitor a machine's health and indicate when the machine starts to develop a fault. In order for such algorithms to be effective, they require raw data collected from machines. Often this involves the placement of accelerometers and other sensory devices for measurements of mechanical behavior. It is possible to extract much of the required information from the electrical signals of the equipment. This is normally a less expensive installation since one only needs access to the lines supplying electric power to the equipment. If these data acqusistion modules are accessible wirelessly, then one can monitor all the interfaced equipment from a central location. To successfully monitor such electrical equipment, a data acquisition unit is required that can sample on five or six channels simultaneously, depending on the switch gear configuration. This thesis details the development of an "endpoint" device that samples the required number of channels to monitor the electrical signals of industrial equipment, and interfaces to a wireless network. The hardware and software design of the "endpoint" is discussed in detail. Also, the software design of the server that receives the data from the "endpoint" is presented. The designed "endpoint" samples up to six channels simultaneously, at a rate of at least 8 kHz per channel, and a data resolution of 16 bits. The data are then transmitted wirelessly to a central server for processing. The system has been tested both in a laboratory environment and at an industrial environment. The desired specifications of the "endpoint" have been verified in both environments. Several "endpoints" have been assembled to form a network and have been tested in a laboratory setting. This work has resulted in the demonstration that an "endpoint" can be constructed using of the shelf components that is suitable for the continuous health monitoring of multi-phase electric machines through a wireless network.

Continuous multi-phase feeding of broiler chickens was evaluated to optimize broiler nutrition and minimize environmental impact related to excess nitrogen in poultry manure. Four experiments were conducted. Experiments 1 and 2 studied effects of continuous multi-phase feeding during a 3-week starting period using battery brooders while experiments 3 and 4 evaluated multi-phase feeding during a traditional 7-week growing period using both battery brooders and floor pens. In the first and second experiments, the nutrient content of the multi-phase diets was changed every 24 hours in comparison to single-phase feeding. Results indicated that during the starter period, continuous multi-phase feeding had no significant influence on feed consumption, daily gain, feed to gain ratio or fecal nitrogen. In the third and fourth experiments, a four phase industry type broiler feeding program was compared to intensive multi-phase feeding programs created by linearly blending three different diets based on typical industry nutrient values and a commercial nutrient modeling computer program (EFG Natal®). In both intensive multi-phase feeding programs, the diets were changed every three days over a 7-week growth period. Broilers in experiment 3 were raised in Petersime battery brooders to primarily access nitrogen balance while birds in experiment 4 were raised in a floor pen on pine shaving litter to resemble commercial broiler production. The results indicated that intensive multi-phase feeding improved body weight gain and feed to gain ratio only in weeks 5 and 6 but not during the overall 7-week period. Nitrogen excretion and nitrogen retention were unaffected by the intensive multi-phase feeding systems. Economic analysis indicated that intensive multi-phase feeding programs could potentially lower feed costs per kilogram of gain. However, the high cost of implementing a continuous multi-phase feeding system may not justify the relatively small gain in lower feed cost per kilogram of gain. In conclusion, continuous multi-phase feeding of broiler chickens using corn-soy diets does not appear to be justified by either increased performance or reduced nitrogen excretion.

This study entails an investigation of a novel moment closure, originally constructed for rarefied-gas prediction, to the modelling of inert, dilute, disperse, particle flows. Such flows are important in many engineering situations. As one example, in internal-combustion engines, fuel is often injected as a spray of tiny droplets and, during combustion, a cloud of tiny soot particles can be formed. These particle phases are often difficult to model, especially when particles display a range of velocities at each location in space. Lagrangian methods are often too costly and many Eulerian field-based methods suffer from model deficiencies and mathematical artifacts. Often, Eulerian formulations assume that all particles at a location and time have the same velocity. This assumption leads to nonphysical results, including an inability to predict particle paths crossing and a limited number of boundary conditions that can be applied. The typical multi-phase situation of many particles is, in many ways, similar to that of a gas compressed of a huge number of atoms or molecules. It is therefore expected that powerful techniques from the kinetic theory of gases could be applied. This work explores the advantages of using a modern fourteen-moment model, originally derived for rarefied gases, to predict multi-phase flows. Details regarding the derivation, the mathematical structure, and physical behaviour of the resulting model are explained. Finally, a numerical implementation is presented and results for several flow problems that are designed to demonstrate the fundamental behaviour of the models are presented. Comparisons are made with other classical models.

A new high-resolution spatial discretization scheme is presented for use within the volume-ofluid (VOF) method. This scheme is an adaptation of the previously published boundary gradient maximization (BGM) scheme, with an extension for time-dependent solutions. The scheme does not explicitly reconstruct the interface, but rather resolves the values of the volume fraction in the area of the interface. The scheme is upwind biased to provide numerical stability, and the face values are limited to meet boundedness criteria and prevent variable overshoot. Unlike most other high-resolution schemes found in the literature, the proposed scheme does not use upwind-biased and downwind-biased “switching” to maintain stability. This thesis presents a number of test cases including 2-D and 3-D cases on both structured and unstructured grids. The results display the method’s ability to predict good shape of the volume fraction interface and resolve the volume fraction discontinuity.

No description available.

No description available.

The laser-induced holographic grating technique was employed to study the dynamic of the intensity grating formation in the azo-dye doped liquid crystals. The liquid crystal material in this study has several mesomorphic phases: Smectic C, Smectic A, Nematic and Isotropic. The first order of diffraction in the mesomorphic phases have been investigated by changing the polarizations of the probe beam.

Disulfide bond information can help the prediction of protein secondary structure, tertiary structure and all-atom coordinates. Most of previous works focused on either state classification or connectivity prediction with some assumption that some constraints were added to make the problem solvable in reality. In this thesis, we propose a multi-phase approach to solve the problem. Our method can export the number of bonds and achieve 90.7% accuracy in the state classification. For the connectivity prediction problem, we use the number of bonds we predict as a base to decide bond pairs. For overcoming the ratio imbalance of samples, we propose a down-sampling method to reducing processing time. Finally, we perform the weighted graph matching algorithm to obtain the bonding pattern, which achieves 63.5% accuracy. We also achieve 48% accuracy for the thorough prediction. Our method is validated by the datasets derived from SWISS-PROT and PDB. The results are better than the previous works.

The transport of multi-phase flow in pipelines can be met in a wide range of industrial applications, including the oil and gas industry, showing great savings in developments. In addition, as the exploration of new fields in oil and gas expands to harsh environments, such as ocean or polar, the multi-phase flow transport sometimes becomes the only feasible option. The important features of such multi-phase flow applications include flow regimes, pressure drop and liquid holdup. The precise estimation of these parameters has significant technical and economical impacts on the design and operation of an oil and gas pipelines. Many prediction correlations and methods have been developed; computational fluid dynamics (CFD) being one of them. This type of modelling approach has many advantages over the conventional approaches such as its ability to solve 3D transient problems; offering access to a wealth of information which with conventional techniques is extremely difficult to obtain. Therefore, interest in applying CFD for multi-phase flow transport in pipelines has been on the rise. This thesis is aimed at presenting CFD simulations based on the use of the Volume of Fluid model (VOF) approach for various conditions of gas-liquid turbulent flow in a horizontal circular pipe. In the current VOF formulation in addition to the secondary phase transport equation, a geometric reconstruction technique based on a piecewise-linear interface construction approach is used for reconstructing the interface. A number of multi-phase studies using different turbulence models to the current one have recently appeared in the open literature for simple flow geometries such as rectangular channels. However, most of them assume specific boundary conditions (such as fully-separated phases for stratified flows, the use of square wave at the inlet to represent slug flow or imposing an interfacial disturbance to initiate slugging). These require case-by-case empirical information such as, interfacial roughness for stratified- or slug frequency for intermittent-flow. However, most of them have not presented any detailed validation of their results. The former two points are very crucial for the design of transport pipelines as a pre-knowledge of the operative flow regime and empirical information are not available at the design stage. The predictive accuracy of the present simulations is tested against most common mechanistic approaches and detailed measurements of stratified two-phase flow in a horizontal pipe of Strand (1993) and have been found to be in reasonable quantitative agreement. For the intermittent flow type cases, the numerical results are qualitatively compared against experiments in a horizontal pipe of Al-alweet (2008). The computed flow data of intermittent flow type are further tested against some empirical and mechanistic correlations; the numerical results are qualitatively in a reasonable agreement. Gas compressibility effects on the simulations of slug flow are also explored and are found to bring about some positive benefit. Overall, the predictive accuracy of the present approach is reasonable and promising, demonstrating the ability of the model to predict different types of flow regimes found in two-phase pipe flows. Furthermore, the proposed model shows potential for general applicability to the design of two-phase pipeline systems as it does not require pre-knowledge of the flow regime or any case-by-case empirical information.

ESR has been used to study multi-phase food systems, including ice cream and chocolate, using both spin probes and spin labels. Chemical and physical methodologies were developed and applied to study the behaviour of 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO), the 5-pentyl derivative (PTMIO) and the water-soluble 5-sulphonate (NaTMIOS) spin probes in hydrophilic and hydrophobic phases over a range of temperatures. Linewidths and hyperfine coupling constants (aN) were derived using fitting and simulating computer software, from which rotational correlation times (tauc) and enthalpies of activation of molecular rotation were calculated. These give an indication of the local environment of the probe. In the hydrophilic phase of ice cream there was a sharp reduction in probe mobility at -18°C, which did not occur in the hydrophobic phase. In chocolate, an essentially hydrophobic system, no sudden changes in mobility were detected although at around 60°C there was a change in the enthalpy of activation. Spectral deconvolution techniques enabled the simultaneous study of NaTMIOS and TMIO in the hydrophilic and hydrophobic phases of ice cream and enabled the study of TMIO spectra in the presence of the underlying spectrum of the radical present in chocolate. Guar gum and xanthan gum are used as stabilisers in ice cream and were spin-labelled using 5-carboxy-TMIO (CTMIO) and 5-amino-TEMPO respectively. The ESR spectra showed that the mobilities of the nitroxide moieties were comparable with the free spin probes. The addition of the gums to a sucrose solution, a model hydrophilic system, had no appreciable effect on the mobility of the NaTMIOS spin probe.