A device for performing an objective eye exam has been developed to automatically determine ophthalmic prescriptions. The closed loop fluidic auto-phoropter has been designed, modeled, fabricated and tested for the automatic measurement and correction of a patient's prescriptions. The adaptive phoropter is designed through the combination of a spherical-powered fluidic lens and two cylindrical fluidic lenses that are orientated 45° relative to each other. In addition, the system incorporates Shack-Hartmann wavefront sensing technology to identify the eye's wavefront error and corresponding prescription. Using the wavefront error information, the fluidic auto-phoropter nulls the eye's lower order wavefront error by applying the appropriate volumes to the fluidic lenses. The combination of the Shack-Hartmann wavefront sensor the fluidic auto-phoropter allows for the identification and control of spherical refractive error, as well as cylinder error and axis; thus, creating a truly automated refractometer and corrective system. The fluidic auto-phoropter is capable of correcting defocus error ranging from −20D to 20D and astigmatism from −10D to 10D. The transmissive see-through design allows for the observation of natural scenes through the system at varying object planes with no additional imaging optics in the patient's line of sight. In this research, two generations of the fluidic auto-phoropter are designed and tested; the first generation uses traditional glass optics for the measurement channel. The second generation of the fluidic auto-phoropter takes advantage of the progress in the development of holographic optical elements (HOEs) to replace all the traditional glass optics. The addition of the HOEs has enabled the development of a more compact, inexpensive and easily reproducible system without compromising its performance. Additionally, the fluidic lenses were tested during a National Aeronautics Space Administration (NASA) parabolic flight campaign, to determine the effect of varying gravitational acceleration on the performance and image quality of the fluidic lenses. Wavefront analysis has indicated that flight turbulence and the varying levels of gravitational acceleration ranging from zero-G (microgravity) to 2G (hypergravity) had minimal effect on the performance of the fluidic lenses, except for small changes in defocus; making them suitable for potential use in a portable space-based fluidic auto-phoropter.

Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / This thesis examines the internal and near external flow fields of a nozzle which produces a naturally precessing fluidic jet (FPJ). The internal flow is investigated by phas-eaveraged Laser-Doppler anemometry (LDA) using a total pressure probe as a phase sensor, while the external flow is investigated primarily by phase-averaged Particle Image Velocimetry (PIV) using a pair of hot-wire probes as the phase sensor, and LDA. The internal flow results partially confirm the flow structure proposed by earlier investigators and demonstrate the effect of the reversed axial flow on the internal jet within the FPI chamber. The results also support the presence of a driving vortex proposed in the literature. A plethora of experimental techniques progressively reveal the characteristics and features of the external precessing jet. The characteristics of the jet at the exit plane are found to be sensitive to inlet conditions and to inlet Reynolds number. The structure of the flow emerging from the FPJ exit is revealed, and found to contain several significant vortical features. Based on the evidence gathered from all the experiments, a new flow structure of the external precessing jet is proposed. Finally, the new experimental data are used to define Strouhal and Reynolds numbers based on the actual characteristics of the emerging jet. These allow the FPJ flow to be compared with other flows such as mechanical precessing jets. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1109306 / Thesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2004

Thesis (Ph.D.) - University of St Andrews, August 2007.

Thesis (M. Eng.(Mechanical))-University of Pretoria, 2005. / Includes bibliographical references. Available on the Internet via the World Wide Web.

Plasma-assisted processing and deposition of materials is an important component of modern industrial applications, with plasma reactors sharing 30% to 40% of manufacturing steps in microelectronics production [1]. Development of new flexible electronics increases demands for efficient high-throughput deposition methods and roll-to-roll processing of materials. The current work represents an attempt of practical design and numerical modeling of a plasma enhanced chemical vapor deposition system. The system utilizes plasma at standard pressure and temperature to activate a chemical precursor for protective coatings. A specially designed linear plasma head, that consists of two parallel plates with electrodes placed in the parallel arrangement, is used to resolve clogging issues of currently available commercial plasma heads, as well as to increase the flow-rate of the processed chemicals and to enhance the uniformity of the deposition. A test system is build and discussed in this work. In order to improve operating conditions of the setup and quality of the deposited material, we perform numerical modeling of the plasma system. The theoretical and numerical models presented in this work comprehensively describe plasma generation, recombination, and advection in a channel of arbitrary geometry. Number density of plasma species, their energy content, electric field, and rate parameters are accurately calculated and analyzed in this work. Some interesting engineering outcomes are discussed with a connection to the proposed setup. The numerical model is implemented with the help of high-performance parallel technique and evaluated at a cluster for parallel calculations. A typical performance increase, calculation speed-up, parallel fraction of the code and overall efficiency of the parallel implementation are discussed in details.

While 3D printing technologies first appeared in the 1980s, prohibitive costs, limited materials, and the relatively small number of commercially available printers confined applications mainly to prototyping for manufacturing purposes. As technologies, printer cost, materials, and accessibility continue to improve, 3D printing has found widespread implementation in research and development in many disciplines due to ease-of-use and relatively fast design-to-object workflow. Several 3D printing techniques have been used to prepare devices such as milli- and microfluidic flow cells for analyses of cells and biomolecules as well as interfaces that enable bioanalytical measurements using cellphones. This review focuses on preparation and applications of 3D-printed bioanalytical devices.

This thesis presents the method of state diagram synthesis and the development of a computer program for designing fluidic sequential feedback • control circuits of the fundamental mode. A paper on state diagram synthesis was authored by Chen and Lee, presented in Detroit and published as ASME paper 73-WA/Flcs-2 in 1973. Hypothetical systems are illustrated by using series of events characterized by the piston positions of some double-acting pneumatic cylinders. In these systems , an action can only begin when the previous action has been completed. Every extension or retraction of a piston is memorized and manifested by a flip-flop element in the feedback circuit. If different combina- tions of control signals result from different combinations of feedback signals, the logic design is straightforward. Otherwise secondary variables are needed to differentiate between repeated appearances of some ambiguous input combinations. A secondary variable is obtained as the output of a fluidic flip-flop with set and reset inputs. When a sufficient number of secondary variables are obtained, they are combined with the feedback signals. Considerations of these variables and their associated logic complementary "don't-care" conditions leads to a set of simplified control equations. The complete process of the circuit design, using state diagram synthesis, has been programmed for a digital computer. After the control equations are obtained , one can take the signal transmission characteristics into account in order to build a hazard-free circuit.

This study was directed toward the development of a bistable wall attachment Flip-Flop device which was capable of directionally controlling particle flow. The particles were transported by a fluid stream which under the influence of wall attachment. The dominant criteria in the development of the device was the achievement of the highest recovery of particles at the active output, without destroying the wall attachment of the fluid stream The experiment was conducted in several distinct stages; each of which was concerned with at least one aspect of wa1l attachment or particle flow. Results derived from one test were used to develop the criteria for the next experimental arrangement. Two experimental models were constructed: one of plywood with only one attachment wall, and one of plexiglas which had two attachment walls and was bistable. The plywood model was used in testing wall attachment and particle recovery as a function of the attachment wall angle. From these tests it was concluded that the optimum wall angle was 18 degrees from the center line of the device. Observations of particle action in the plywood model led to the incorporation of additional features in the plexiglas model. They were: an extended nozzle, the elimination of the separation bubble, and the development of smooth transitions at the corners. The plexiglas model was used to investigate optimum splitter location, the effect of jet velocity on recovery efficiency, the effect of vents on the performance of the device, and the performance of the device using a water jet. In the last stages of testing, moving parts and additional output features were used in conjunction with the bistable device to improve the collection efficiency. Some observations resulting from the data gathered in the various tests include: 1. The higher the jet velocity, the greater the wall attachment. 2. The higher the density and viscosity of the fluid stream the greater the recovery of particles at the active output. 3. Particles with large inertial forces were controlled less by the attached jet stream. The addition 0f vents in the device may produce greater particle recovery. 5. The use of moving parts and variations in the output leg design can produce 100 percent particle recovery. This study indicated that it was possible to control the directional flow of particles with the bistable wall attachment device which was developed. However, the pure fluid bistable device could not achieve 100 percent recovery of particles. The addition of moving parts or variations in the output leg design can produce 100 percent recovery of the particles. The use of a bistable device could provide simplicity, reliability and adaptability in transporting materials for industrial processes.

Persons with transfemoral (above knee) and transtibial (below knee) prostheses experience changes in the volume of their residual limb during the course of the day. These changes in volume unavoidably lead to changes in quality of fit of the prosthesis, skin irritations, and soft tissue injuries. The associated pain and discomfort can become debilitating by reducing one's ability to perform daily activities. While significant advancements have been made in prostheses, the undesirable pain and discomfort that occurs due to the volume change is still a major challenge that needs to be solved. The overall goal of this research is to develop smart prosthetic sockets that can accommodate for volume fluctuations in the residual limb. In this research, fluidic flexible matrix composite wafers (f2mc) are integrated into the prosthetic socket for volume regulation. The f2mc's are flexible tubular elements embedded in a flexible matrix. These tubular elements are connected to a reservoir, and contain an internal fluid such as air or water. Fluid flow between the tubes and reservoir is controlled by valves. A linear finite element model has been created to better understand output response and stiffness of the f2mc wafers for different design variables. Results demonstrate that wind angle, latex thickness, and material selection can be used to tailor the wafers for different applications. Through experiments, f2mc's have been shown to achieve nearly 100% strain through the thickness when pressurized to about 482.6 kPa (70 psi). The displacement results shown through these tests show great promise in applications of socket integration to compensate for volume change. / Master of Science

Yes / Purpose: Dexibuprofen is an enantiomer of ibuprofen with low bioavailability which results from its hydrophobic nature. Nanosuspensions have developed a podium to solve the in vitro dissolution problem that frequently occurs in current research. Materials and methods: The drug and polymer solutions were mixed in a microchannel fluid reactor and the successive embryonic nanosuspension was decanted into a vial having the polymer solution. The impact of different process and formulation parameters including inlet angle, antisolvent and solvent flow rate(s), mixing time, drug concentration, polymer type and concentration was evaluated. Results and discussion: Stable dexibuprofen nanocrystals with a particle size of 45±3.0 nm and polydispersity index of 0.19±0.06 were obtained. Differential scanning calorimetry and powder X-ray diffraction confirmed the crystallinity. The key parameters observed were inlet angle 10°, antisolvent to solvent volume of 2.0/0.5 mL/min, 60 minutes mixing with 5 minutes sonication, Poloxamer-407 with a concentration of 0.5% w/v and drug concentration (5 mg/mm). The 60-day stability studies revealed that the nanocrystals were stable at 4°C and 25°C. The scanning electron microscopy and transmission electron microscopy images showed crystalline morphology with a homogeneous distribution. Conclusion: Stable dexibuprofen nanocrystals with retentive distinctive characteristics and having marked dissolution rate compared to raw and marketed formulations were efficiently fabricated. In future perspectives, these nanocrystals could be converted to solid dosage form and the process can be industrialized by chemical engineering approach