Robotics and autonomous systems (RAS) have great potential to propel the world to future growth. Electroadhesion is a promising and potentially revolutionising material handling technology for manufacturing automation applications. There is, however, a lack of an in-depth understanding of this electrostatic adhesion phenomenon based on a confident electroadhesive pad design, manufacture, and testing platform and procedure. This Ph.D. research endeavours to obtain a more comprehensive understanding of electroadhesion based on an extensive literature review, theoretical modelling, electrostatic simulation, and experimental validation based on a repeatable pad design, manufacture, and testing platform and procedure.

In the theoretical analysis of high speed rotor bearing systems, it is common to use four displacement and four velocity based coefficients, which characterise the behaviour of the lubricating fluid film. Although a great deal of work has been published establishing theoretical models of all types of hydrodynamic journal bearings, the large amount of experimental work has centred on relatively low speed conditions. This work presents a contribution to the experimental study of the static and dynamic characteristics of oil films in journal bearings used in high-speed rotating machinery. The main objectives of the work are: • To devise new experimental techniques for the measurement of dynamic coefficients suitable for use at high rotational speeds • To design, manufacture, assemble and commission a test facility to measure the static and dynamic characteristics of journal bearings at speeds up to 30000 rpm • To determine the static and dynamic characteristics of a 5 Pad Tilting Pad Journal Bearing Unit of 80 mm diameter at speeds up to 25 000 rpm using the said test facility. New techniques are particularly necessary for the measurement of velocity coefficients because these invoke the necessity of imposing a velocity on to the bearing housing and previous techniques have utilised synchronous motion of the bearing. Consequently a new experimental procedure for measuring the four velocity or damping coefficients of an oil film journal bearing from imposed dynamic "orbits" has been devised called the "double pulse" technique. All four velocity coefficients are derived from one imposed journal centre dynamic orbit and, therefore may be regarded as being obtained at the same time. The method requires the production of a "cross- over" point similar to that of a "figure of eight" shaped orbit and utilises the "cross-over" point therein. Coefficients are initially evaluated in a co-ordinate system, which is chosen to align with the designated parts of the measured orbit. Each coefficient is then evaluated from single values of instantaneous imposed force and resulting journal centre velocity. Coefficients are them converted into any other desired axes system. The result is a simpler experimental procedure, with reduced uncertainty compared to hitherto existing methods. The use of non-sinusoidal excitation of the oil film was explored, in the form of applying a step-pulse train load pattern to produce a cross-over pattern in the journal displacement ·orbit'. Experimental tests were completed on a tilting pad bearing at speeds up to 15 000 rpm inclusive. At speeds above this, the bearing exhibited a vibrational response, which precluded the accurate measurement of journal centre displacement.

Esta tese estuda a emissão de ruído de alta frequência em freios automotivos, conhecida como squeal. Para tanto, uma série de ensaios foram executados em sistemas de freio em um dinamômetro inercial. Foram colocados acelerômetros na pastilha e no caliper em três direções ortogonais, e foram testados dois diferentes tipos de sistemas de freio comerciais. Os ensaios revelaram que, durante os períodos silenciosos, o movimento vibratório da pastilha acontece tanto na direção tangencial radial quanto na direção radial no plano definido pelo disco, além da direção axial. Estas vibrações ocorrem de modo independente, não mostrando acoplamento entre os movimentos. Durante os períodos de emissão sonora intensa, os valores de vibração aumentam significativamente e ocorre o acoplamento dos movimentos nas direções tangencial e radial, que passam a apresentar sincronismo de fase e de frequência. O movimento da pastilha na direção radial é explicado pelos modos de vibração do disco, e pastilha e disco são tratados como dois osciladores fracamente acoplados. Para o tratamento de osciladores, utiliza-se o modelo de Kuramoto. O sincronismo, neste modelo, ocorre devido ao acoplamento entre os osciladores e devido à proximidade das frequências naturais de pastilha e disco. A aplicação do modelo nos sistemas ensaiados mostrou boa aderência aos dados experimentais. Finalmente, é proposta a utilização de um coeficiente adimensional de maneira a incluir no estudo dinâmico do sistema variáveis puramente tribológicas. / This paper studies friction induced high frequency noise in automotive brakes, known as squeal. Aiming this purpose, a series of experiments were performed using brake systems in an inertial dynamometer. Accelerometers were installed on pad and caliper, measuring in three orthogonal directions, in two different commercial brake systems. The tests showed that, during the silent runs, pad vibration happens in tangential and radial directions, besides the axial direction, considering the coordinate reference frame on the plane defined by the brake disc. These vibrations happen in an independent fashion, indicating no coupling between motions in different directions. During the squeal periods, however, vibration amplitudes increase sharply and phase and frequency synchronization between tangential and radial vibrations is observed, indicating vibration coupling. Pad movement in radial direction is caused by disc in-phase vibration mode. Pad and disc are treated as two harmonic oscillators according to Kuramoto model. In this model, synchronization is caused by weak coupling between pad and disc natural frequencies, due to frequency proximity. A numerical simulation of Kuramoto model was able to emulate the experimental data. Finally, a new non-dimensional coefficient is proposed in order to include in this dynamic model the influence of pure tribological effects.

A novel tilting pad journal bearing model including pivot flexibility as well as temporal fluid inertia effects on the thin film fluid flow aims to accurately predict the bearing forced performance. The predictive model also accounts for the thermal energy transport effects in a TPJB. A Fortran program with an Excel GUI models TPJBs and delivers predictions of the bearing static and dynamic forced performance. The calculation algorithm uses a Newton-Raphson procedure for successful iterations on the equilibrium pad radial and transverse displacements and journal center displacements, even for bearings pads with very soft pivots. The predictive model accounts for the effect of film temperature on the operating bearing and pad clearances by calculating the thermal expansion of the journal and pad surfaces. The pad inlet thermal mixing coefficient (lambda) influences moderately the predicted fluid film temperature field. Pad pivot flexibility decreases significantly and dominates the bearing stiffness and damping coefficients when the pivot stiffness is lower than 10% of the fluid film stiffness coefficients (with rigid pivots). Pivot flexibility has a more pronounced effect on reducing the bearing damping coefficients than the stiffness coefficients. Pad pivot flexibility may still affect the bearing behavior at a light load condition for a bearing with a large pad preload. Pad pivot flexibility, as well as the fluid inertia and the pads’ mass and mass moment of inertia, could influence the bearing impedance coefficients, in particular at high whirl frequencies. The stiffness and damping coefficients of a TPJB increase with a reduction in the operating bearing and pad clearances. The work delivers a predictive tool benchmarked against a number of experimental results for test bearings available in the recent literature. The static and dynamic forced performance characteristics of actual TPJBs can not be accurately predicted unless their pad flexibility and pivot flexibility, fluid film temperature, pad inlet thermal mixing coefficient, operating bearing and pad clearances, among others are well known in advance. However, the extensive archival literature showcasing test procedures and experimental results for TPJBs does not report the above parameters. Thus, reasonable assumptions on the magnitude of certain elusive parameters for use in the predictive TPJB model are necessary.

The thesis is mainly focused on the investigation of optimal process operation, which is appropriate for new-type stacking package product to achieve the assembly products of two or more packages. By melting solder balls to form the stacking package products, the eventual goals of lightness, thinness and smallness will be accomplished. To increase and stabilize the production yield of stacking package products, different flux, different temperature setting with reflow oven, and different flux dipping method were used. With Taguchi design of experiment, the solder balls combined situations under varied conditions were observed. The best process character of new-type integration assembly products was achieved. The experimental results and mass production data prove that different flux type and temperature setting with reflow oven won¡¦t influence the solder balls connection between two package products. Only the flux dipping method will directly affect solder balls connection between two package products. The abnormal phenomenon is the so-called cold joint in assembly plants. With innovation, silicon gel head is used as a flux adhesive way to achieve the goal of flux transferred. This method can be used in integration process of new-type stacking package products. That will certainly assure that every solder ball on each package product can be helpful for adhesion of flux. The experiments proved that the yield rate of solder balls connection of two package products is 100% after the stacking package products through reflow oven. This proves that using flux with silicon gel head on new-type stacking package products is the best way of process operation. The innovation of this new process has been granted a patent by the Patent office, ROC. Although this is a simple invention, it will bring profit to ASE Co. as well and ensure the leadership of new-type stacking package products in related industries. Keywords: Stack¡BSolder Ball¡BCold Joint¡BSilicon Pad

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This dissertation presents a series of studies relating to pad-wafer and brush-wafer contact characterization in planarization and post-planarization processes. These are also evaluated with the purposes of minimizing environmental impact and reducting cost of ownership.Firstly, a new method using spectral analysis based on real-time raw friction data is developed to quantify the total amount of mechanical interaction in the brush-fluid-wafer interface in terms of stick-slip phenomena in post-planarization scrubbing. This new method is remarkable from the standpoint of its potential to eliminate having to perform a multitude of experiments needed for constructing and interpreting Stribeck curves, and its application to processes where Stribeck curves fail to yield any useful data. Moreover, this method is applied to investigate the effect of brush roller design on scrubbing process and to analyze behaviors of eccentric brushes.In order to study pad-wafer contact in planarization processes, a mechanical characterization method (incremental loading test) is developed and applied to analyze different types of pads and pad surfaces subjected to various treatments. Along with optical interferometry and theoretical analysis, flow resistance due to pad land area topography can be estimated.The greatest contribution of this dissertation involves development of real pad-wafer contact area measurement technique using confocal microscopy. The real pad-wafer contact area is a difficult property to measure in planarization, yet it is a key feature to further understand the process. A custom-made sample holder with a sapphire window and a miniature load cell is used to collect confocal images at controlled values of down force.At last, the two newly developed techniques (incremental loading test and real pad-wafer contact area measurement using confocal microscopy) together with dual emission UV enhanced fluorescence imaging are utilized to investigate conditioning effects in planarization process.

Dekkera and the closely related Brettanomyces are important yeasts in food and beverage production in part due to the metabolism of hydroxycinnamic acids (HCAs). There is a dearth of information concerning the role Brettanomyces spp. play in the food or beverage from which they are isolated and although Dekkera spp. have been investigated further there are discrepancies and questions yet to be answered. Representatives of both genera were examined to define growth and metabolism of individual HCAs in synthetic media. In addition, growth with combinations of HCAs was investigated for the first time. The results provide a comprehensive overview of HCA metabolism and volatile product formation for these genera. Furthermore, results have been confirmed in a semidefined wine medium that more closely resembled the physio-chemical parameters found in the typical wine environment. The enzymes responsible for the metabolism of HCAs were examined in Dekkera and Brettanomyces. Dekkera yeasts are known to enzymatically convert HCAs into vinylphenols (VPs) and ethylphenols (EPs). These products are indicative of Dekkera contamination. The first enzyme in the two-step HCA ─ VP ─ EP biochemical pathway is a hydroxycinnamic acid decarboxylase (HCD). This enzyme has been previously characterised from a single Dekkera strain. The second enzyme, vinylphenol reductase (VPR) has never been isolated or characterised from any microorganism. In order to further elucidate the HCA ─ VP ─ EP pathway, cell extracts were prepared from all five Dekkera and Brettanomyces spp. to evaluate activity against HCAs and VPs. Brettanomyces spp. were unable to metabolise HCAs indicating that these yeast do not have a functional HCD enzyme. Both Dekkera spp. have substrate inducible HCD activity. Temperature and pH optima were 40ºC and 5.75-6.00, respectively. The active protein was purified from cell extracts of D. anomala CBS 77 and a partial sequence was obtained. 3’RACE PCR was performed and a near complete gene sequence determined. This sequence does not have homology to HCA decarboxylase enzymes previously characterised from yeasts and bacteria and thus may represent a novel enzyme not previously described. Biochemical characterisation of the vinylphenol reductase (VPR) enzyme was also undertaken. VPR activity was found for all 5 Dekkera and Brettanomyces spp. Activity was greatest at pH 6 and between 40-50ºC and was induced by both VPs and HCAs. Data obtained during growth experiments indicated that HCAs, and in particular ferulic acid, inhibited the growth of Dekkera and Brettanomyces spp. On this basis a more detailed study was carried out to determine the concentrations required to prevent growth in various media. In a modified red wine a concentration 0.1 mM ferulic acid inhibited growth and 2 mM prevented cultures of both D. anomala and D. bruxellensis from becoming established even when re-inoculated into to a fresh HCA-free medium. Scanning electron micrographs revealed that ferulic acid caused physical damage to Dekkera cells upon exposure. This work could lead to the development of an alternative method for the control of Dekkera in wine or other food products. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1454852 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2010

Despite many research pieces on brake systems, there is still research to be done on brake pad geometry and the dissipation of heat during brake engagements using the finite element analysis method. Brake application is a process in which the kinetic energy of the vehicle is mostly converted into thermal energy and then dissipated in the form of heat. Based on dynamometer test results it was seen that brake pad temperatures could reach up to 600° C [23]. Preliminary research using computer modeling software has shown that heat dissipation in brake pads with wavy geometries and air channels from the top to bottom is much better compared to pads that do not have those specific features. Brake pads that dissipate heat faster are prone to brake fade and other braking issues that may arise due to overheating [15]. For this research, two readily available brake pads and two designs of brake pads with new geometry were modeled using CAE software. Finite element analysis was then performed to test how well each brake pad dissipated heat after reaching brake fade temperatures. The readily available brake pads were from Power Stop and Wagner [26]. ANSYS Space Claim [25] was used to design and model the brake pads, ANSYS 18.2 [24] was used to perform the finite element analysis on the pads. After performing the analysis, results indicate that a brake pad with a design that had zones for turbulent air at ambient conditions and convection slots from the top to the bottom decreased in temperature by about 90° C more in the same time compared to the conventional design. By studying the changing values of the convection heat transfer coefficient with velocity, the placing of the turbulence zones can be more precise in order attain greater airflow to remove heat from the brake pad quicker.

The diploma thesis deals with the study of the process of grinding aggregates of particles of a mixture of powdered lanthanide oxides in the dowanol solvent. The formed dispersions were characterised and used for the preparation of printing inks and subsequently for the printing of labels with chemical codes readable by XRF spectrometry. The aim was to study the milling process, to verify the reliability of reading and recognition of marks with the appropriate codes and to monitor the influence of the additive of the up-conversion powder on the resulting relative intensities of the elements in the chemical code. The statistical significance of the differences in the averages of relative intensities was assessed based on the Student's t test.