Electrohydrodynamic focusing and light propagation in 2-dimensional microfluidic devices for preconcentration of low abundance bioanalytes

This thesis presents work on electrohydrodynamic focusing (EHDF) and photon transmission to aid the development of species preconcentration and identification. EHDF is an equilibrium focusing method, where a target ion becomes stationary under the influence of a hydrodynamic force opposed by an electromigration force. To achieve this one force must have a non-zero gradient. In this research a novel approach of using a 2-dimensional planar microfluidic device is presented with an open 2D-plane space instead of conventional microchannel system. Such devices can allow pre-concentration of large volume of species and are relatively simple to fabricate. Fluid flow in these systems is often very complex making computer modelling a very useful tool. In this research, results of newly developed simulations using COMSOL Multiphysics® 3.5a are presented. Results from these models were compared to experimental results to validate the determined flow geometries and regions of increased concentration. The developed numerical microfluidic models were compared with previously published experiments and presented high correspondence of the results. Based on these simulations a novel chip shapes were investigated to provide optimal conditions for EHDF. The experimental results using fabricated chip exceeded performance of the model. A novel mode, named lateral EHDF, when test substance was focused perpendicularly to the applied voltage was observed in the fabricated microfluidic chip. As detection and visualisation is a critical aspect of such species preconcentration and identification systems. Numerical models and experimental validation of light propagation and light intensity distribution in 2D microfluidic systems was examined. The developed numerical mode of light propagation was used to calculate the actual light path through the system and the light intensity distribution. The model was successfully verified experimentally in both aspects, giving results that are interesting for the optimisation of photopolymerisation as well as for the optical detection systems employing capillaries

Internet of Things. Information Processing in an Increasingly Connected World

This open access book constitutes the refereed post-conference proceedings of the First IFIP International Cross-Domain Conference on Internet of Things, IFIPIoT 2018, held at the 24th IFIP World Computer Congress, WCC 2018, in Poznan, Poland, in September 2018. The 12 full papers presented were carefully reviewed and selected from 24 submissions. Also included in this volume are 4 WCC 2018 plenary contributions, an invited talk and a position paper from the IFIP domain committee on IoT. The papers cover a wide range of topics from a technology to a business perspective and include among others hardware, software and management aspects, process innovation, privacy, power consumption, architecture, applications

THE DEVELOPMENT OF A NOVEL ELECTRO-MAGNETIC FORCE MICROSCOPE

This thesis describes the development of a new type of Magnetic Force Microscope (MFM) probe based on a unique electromagnetic design. In addition the design, construction and testing of a new MFM system, complete in both hardware and software, is also described. The MFM allowed initial tests on prototypes of the new probe, and is to provide a base for future new probe integration. The microscope uses standard MFM micro-cantilever probes in static modes of imaging. A new computer hosted DSP control system, software, and its various interfaces with the MFM have been integrated into the system. The system has been tested using standard probes with various specimens and satisfactory results have been produced. A novel probe has been designed to replace the standard MFM magnetic coated tip with a field generated about a sub-micron aperture in a conducting film. The field from the new probe is modelled and its imaging capability investigated, with iterative designs analysed in this way. The practical construction and potential problems therein, of the probe are also considered. Test apertures have been manufactured, and an image of the field produced when operating is provided as support to the theoretical designs. Future methods of using the new probe are also discussed, including the examination of the probe as a magnetic write mechanism. This probe, integrated into the MFM, can provide a new method of microscopic magnetic imaging, and in addition opens a new potential method of magnetic storage that will require further research

AI/ML Algorithms and Applications in VLSI Design and Technology

An evident challenge ahead for the integrated circuit (IC) industry in the nanometer regime is the investigation and development of methods that can reduce the design complexity ensuing from growing process variations and curtail the turnaround time of chip manufacturing. Conventional methodologies employed for such tasks are largely manual; thus, time-consuming and resource-intensive. In contrast, the unique learning strategies of artificial intelligence (AI) provide numerous exciting automated approaches for handling complex and data-intensive tasks in very-large-scale integration (VLSI) design and testing. Employing AI and machine learning (ML) algorithms in VLSI design and manufacturing reduces the time and effort for understanding and processing the data within and across different abstraction levels via automated learning algorithms. It, in turn, improves the IC yield and reduces the manufacturing turnaround time. This paper thoroughly reviews the AI/ML automated approaches introduced in the past towards VLSI design and manufacturing. Moreover, we discuss the scope of AI/ML applications in the future at various abstraction levels to revolutionize the field of VLSI design, aiming for high-speed, highly intelligent, and efficient implementations

Dependable Embedded Systems

This Open Access book introduces readers to many new techniques for enhancing and optimizing reliability in embedded systems, which have emerged particularly within the last five years. This book introduces the most prominent reliability concerns from today’s points of view and roughly recapitulates the progress in the community so far. Unlike other books that focus on a single abstraction level such circuit level or system level alone, the focus of this book is to deal with the different reliability challenges across different levels starting from the physical level all the way to the system level (cross-layer approaches). The book aims at demonstrating how new hardware/software co-design solution can be proposed to ef-fectively mitigate reliability degradation such as transistor aging, processor variation, temperature effects, soft errors, etc. Provides readers with latest insights into novel, cross-layer methods and models with respect to dependability of embedded systems; Describes cross-layer approaches that can leverage reliability through techniques that are pro-actively designed with respect to techniques at other layers; Explains run-time adaptation and concepts/means of self-organization, in order to achieve error resiliency in complex, future many core systems

The Conference on High Temperature Electronics

The status of and directions for high temperature electronics research and development were evaluated. Major objectives were to (1) identify common user needs; (2) put into perspective the directions for future work; and (3) address the problem of bringing to practical fruition the results of these efforts. More than half of the presentations dealt with materials and devices, rather than circuits and systems. Conference session titles and an example of a paper presented in each session are (1) User requirements: High temperature electronics applications in space explorations; (2) Devices: Passive components for high temperature operation; (3) Circuits and systems: Process characteristics and design methods for a 300 degree QUAD or AMP; and (4) Packaging: Presently available energy supply for high temperature environment

Characteristics of UHF transistors using autoregistered structures

The basis of a novel bipolar transistor structure was proposed by Dr R. Aubusson of Middlesex Polytechnic in 1977. The novelty lies in replacing the conventional overlay transistor's P+ base grid with a refractory metal grid, in order (a) to lower the base resistance and (b) to autoregister the emitter. It was claimed that the linearity of the transistor would also be improved. A number of questions raised by this idea have been investigated, the methods and conclusions of which are presented here. Plausible structures, using the metal base grid, are proposed and compared with conventional structures. Some advantages are seen to be possible. The current understanding of distortion analysis applied to transistors is reviewed. The main ideas are presented in a unified manner and are extended to higher order. A number of the transistor's second order effects are analysed in a novel fashion. The metal base grid transistor is analysed and compared with conventional transistors, with favourable results. Practical aspects of fabricating the metal base grid transistor were investigated. A procedure for deposition has been determined and is presented here along with the film physical and electrical characteristics. Analysis of the tungsten-silicon interface shows the suitability of the metallization as a base grid. Suitable means of delineating the tungsten film have been assessed and a working procedure determined. Subsequent deposition of various insulators has been investigated and the problems associated with the readily oxidized tungsten film have been overcome. Formation of the emitter, requiring further high temperature processing, has been assessed in view of the limitations imposed by the preformed base metallization. In summary, it has been shown that the novel structure can be constructed and that significant performance improvement is to be expected, although a full realization was not possible within the resource constraints of the project