Film blowing process is a flexible mass production technology used for manufacturing thin polymeric films. Its flexibility in using an existing die to produce films of different width and thickness, just by controlling process conditions such as, extrudate velocity, excess pressure, and line speed, makes it an attractive process with less capital investment. Controlling the process conditions to obtain a stable bubble, however, is not a trivial task. It is a costly trial and error procedure, which could result is a large wastage of material and other resources. Hence, it is necessary to develop methods to simulate the process and design it using numerical experiments. This important need of the industry defines the objective of this work. In this dissertation, a transient, axisymmetric, nonisothermal, viscoelastic model is developed to simulate the process, and it is solved using finite element method. Material behavior of polymer melt is described using a modified Phan-Thien-Tanner model in the liquid??like region, and anisotropic Kelvin??Voight model in the solid zone, and the transition is modeled using a simple mixture theory. Crystallization kinetics is described using a modified Avrami model with factors to account for the influence of temperature and strain. Results obtained are compared with available experimental results and the model is used to explore stability issues and the role of different parameters. Software developed using this model comes with a GUI based pre- and post-processor, and it can be easily adapted to use other constitutive models.

The proposed work provides a new definition of the pressure derivative function [that is the β-derivative function, Δp βd(t)], which is defined as the derivative of the logarithm of pressure drop data with respect to the logarithm of time This formulation is based on the "power-law" concept. This is not a trivial definition, but rather a definition that provides a unique characterization of "power-law" flow regimes which are uniquely defined by the Δp βd(t) function [that is a constant Δp βd(t) behavior]. The Δp βd(t) function represents a new application of the traditional pressure derivative function, the "power-law" differentiation method (that is computing the dln(Δp)/dln(t) derivative) provides an accurate and consistent mechanism for computing the primary pressure derivative (that is the Cartesian derivative, dΔp/dt) as well as the "Bourdet" well testing derivative [that is the "semilog" derivative, Δpd(t)=dΔp/dln(t)]. The Cartesian and semilog derivatives can be extracted directly from the power-law derivative (and vice-versa) using the definition given above.

In general the automotive electromagnetic environment is severe because of the presence of DC motors and ignition. In this thesis, electromagnetic interference and electromagnetic susceptibility are studied. This thesis is divided intro three parts. In Part I we introduce the specification of digital TV (DVB-T) in Taiwan. In Part 2 the reception of digital TV in vehicle and in laboratory is compared. The measurement in vehicle is conducted in order to understand the source of interference and how the disturbance occurs. The standard test in laboratory has to do with the transient susceptibility which is based on ISO 7637. We then analyze the implication of different pulses mandated in ISO 7637. The results are compared with those obtained in vehicular measurement. In Part 3 remedy is proposed to reduce the interference to digital TV.

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A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice. Challenges and difficulties have been to obtain parameter values for components that are relevant for the high frequencies produced by the short rise time in lightning surges. The main conclusions are: the maximum current in the lightning discharge has the largest impact on the system voltages and surges in the external grid can produce standing waves in the system, causing significant overvoltages even in low voltage systems. The simulations produced larger overvoltages than would occur in a real system, which also would dampen the high frequency signals to a larger extent. Further work to obtain models better suited for high frequency simulation is suggested.

This document explores and questions notions of place, identity, and transformation caused by displacement.

Vector Fitting is employed to approximate the Frequency Response Analysis (FRA) measurement data of a 13.8 kV/136.8 kV, 50-MVA single phase transformer. The frequency response of the primary and secondary coils as well the coupling between the coils have been measured in the frequency range of up to 2 MHz. The measured data includes the stray capacitances that exist between the coils. A circuit synthesis model is used to represent the measured data in the form of a two-port passive RLC network. The derived network is implemented in a commonly used power system transient simulator (PSCAD/EMTDC). The proposed RLC model is passive to ensure the stability of the network. The model can be used to investigate transient response of the transformer including the simulation of switching and lightning overvoltage transients. The results are compared with those derived from existing simple models.

The current project is to develop a transient expression system for Chinese Hamster Ovary (CHO) cells based on autonomous replication and retention of plasmid DNA. The expression system, named Epi-CHO comprises (1) a recombinant CHO-K1 cell line encoding the Polyoma (Py) virus large T-Antigen (PyLT-Ag), and (2) a DNA expression vector, pPy/EBV encoding the Py Origin (PyOri) for autonomous replication and encoding the Epstein-Barr virus (EBV), Nuclear Antigen-1 (EBNA-1) and EBV Origin of replication (OriP) for plasmid retention. The CHO-K1 cell line expressing PyLT-Ag, named CHO-T was adapted to suspension growth in serum-free media (EXCELL-302) to facilitate large scale transient transfection and recombinant (r) protein production. PyLT-Ag-expressed in CHO-T supported replication of PyOri-containing plasmids and enhanced growth and r- protein production. A scalable cationic lipid based transfection was optimised for CHO-T cells using LipofectAMINE-2000??. Destabilised Enhanced Green Fluorescence Protein (D2EGFP) and Human Growth Hormone (HGH) were used as reporter proteins to demonstrate transgene expression and productivity. Transfection of CHO-T cells with the vector pPy/EBV encoding D2EGFP showed prolonged and enhanced EGFP expression, and transfection with pPy/EBV encoding HGH resulted in a final concentration of 75 mg/L of HGH in culture supernatant 11 days following transfection.

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A number of mathematical models are used nowadays to describe behaviour of the reallife water distribution system (WDS). It is a well known fact that, to have any meaningful use, any WDS mathematical model must be calibrated first. Here, calibration is defined as process in which a number of WDS model parameters are adjusted until the model mimics behaviour of the real WDS as closely as possible. In this thesis, WDS mathematical models that are used to model water quantity aspect only are analysed. Three hydraulic models considered here are: (1) steady-state flow model, (2) quasi-steady flow (extended period simulation) model and (3) unsteady flow model. The calibration problem analysed here is formulated as a constrained optimisation problem of weighted least square type with the objective defined in a way that enables effective incorporation of prior information on calibration parameters. WDS calibration problem is then analysed in detail, including special issues of identifiability, uniqueness and stability of the problem solution. A list of diagnostic and other statistics and analysis is presented to improve existing calibration approaches by providing partial insight into the calibration process. Calibration of WDS hydraulic models is further improved by the development of new hybrid optimisation method. Being closely related to calibration, the problem of sampling design for calibration of WDS hydraulic models is also addressed here. First, sampling design is formulated as a constrained two-objective optimisation problem. Then, two novel models are developed to solve it. The first model is based on standard, single-objective Genetic Algorithms (SOGA). The second model is based on multi-objective Genetic Algorithms (MOGA). Finally, all novel methodologies presented here are verified successfully on multiple case studies that involve both artificial and real-life WDS. At the end, relevant conclusions are drawn and suggestions for further research work are made.