372 research outputs found

    Integration of biomolecular logic principles with electronic transducers on a chip

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    Boolean operations applied in biology and integrated with electronic transducers allow the development of a new class of digital biosensors for the detection of multiple input signals simultaneously and in real-time. With the help of Boolean functions (AND, OR, etc.), an electrical output signal will be directly delivered, representing a ”1” or “0” binary notation, corresponding to a “true” or “false” statement, respectively. Such digital biosensors have the future potential to create medical devices and systems for intelligent or smart diagnostics. The present thesis describes the realization of different enzyme-based biomolecular logic gates combined with electronic transducers for the possible application in medicine or food industry. In a first concept, a so called BioLogicChip is developed combining a “sense-act-treat” function integrated on one chip. The present system exemplarily mimics an “artificial pancreas” designed as a closed-loop drug-release system. A glucose sensor is constructed as enzyme-based AND logic gate, a temperature-depending hydrogel imitates the actuator function switching ON and OFF with its shrinking or swelling property, and an additional insulin sensor is developed to monitor and control the release of the drug (here: insulin) from the actuator. In this study, the results of the individual components such as the amperometric glucose sensor, the temperature-dependent hydrogel and the amperometric insulin sensor are presented, which are necessary to create such BioLogicChip. Moreover, a digital adrenaline biosensor is developed to proof the catheter position during adrenal vein sampling. The sensor consists of an oxygen electrode modified by a bi-enzyme system with the enzymes laccase and pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) to realize substrate-recycling principle to detect low adrenaline concentrations (in the nanomolar concentration range). The sensor`s behavior at different pH values and at different temperatures is studied. Measurements in Ringer`s solution are performed. In addition, the sensitivity of the biosensor to other catecholamines such as noradrenaline, dopamine and dobutamine is investigated. Furthermore, the adrenaline biosensor is successfully examined in human blood plasma. Finally, “proof-of-principle” experiments have been performed by combining the adrenaline biosensor with Boolean operations to get a rapid qualitative statement of the presence or absence of adrenaline, thus validating the correct position of the catheter in a YES/NO form. This adrenaline biosensor is further miniaturized as a thin-film platinum adrenaline biosensor. Here, the bioelectrocatalytical measurement principle is applied by immobilization of the enzyme PQQ-GDH to detect adrenaline in the nanomolar concentration range, too. The measurement conditions such as pH value, glucose concentration in the analyte solution and temperature are optimized with regard to a high sensitivity and low detection limit. Also, this sensor has been verified towards other catecholamines (noradrenaline, dopamine and dobutamine). The platinum thin-film adrenaline biosensor is successfully applied in blood plasma for the detection of different spiked adrenaline concentrations. Furthermore, the developed adrenalin biosensor is able to detect the concentration difference between adrenal blood and peripheral blood. In contrast to the above-mentioned amperometric biosensor examples for biomolecular gates, also a field-effect-based platform is given attention in this thesis. The field-effect electrolyte-insulator-semiconductor (EIS) sensor consists of a layer structure of Al/p-Si/SiO2/Ta2O5 and is used to create an acetoin biosensor for the first time to control different fermentation processes. The sensor chip is modified by the enzyme acetoin reductase from B. clausii DSM 8716T for the catalytical reaction of (R)-acetoin to (R,R)-butanediol and meso-butanediol, respectively, in the presence of NADH. The linear measurement range, the optimal immobilization strategy (cross-linking by using glutaraldehyde and adsorptive binding) as well as the optimal working pH value and long-term stability are investigated by means of constant-capacitance measurements. Finally, the acetoin sensor was successfully applied in wine probes to detect different spiked acetoin concentrations. The sensor shows opportunities to be further developed as digital acetoin biosensor

    The 1992 4th NASA SERC Symposium on VLSI Design

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    Papers from the fourth annual NASA Symposium on VLSI Design, co-sponsored by the IEEE, are presented. Each year this symposium is organized by the NASA Space Engineering Research Center (SERC) at the University of Idaho and is held in conjunction with a quarterly meeting of the NASA Data System Technology Working Group (DSTWG). One task of the DSTWG is to develop new electronic technologies that will meet next generation electronic data system needs. The symposium provides insights into developments in VLSI and digital systems which can be used to increase data systems performance. The NASA SERC is proud to offer, at its fourth symposium on VLSI design, presentations by an outstanding set of individuals from national laboratories, the electronics industry, and universities. These speakers share insights into next generation advances that will serve as a basis for future VLSI design

    A survey on personal computer applications in industrial design process

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    Thesis (Master)--Izmir Institute of Technology, Industrial Design, Izmir, 1999Includes bibliographical references (leaves: 157-162)Text in English, Abstract: Turkish and Englishxii, 194 leavesIn this thesis, computer aided design systems are studied from the industrial designer's point of view. The study includes industrial design processes, computer aided design systems and the integration aspects.The technical issues are priorly studied, including current hardware and software technologies. The pure technical concepts are tried to be supported with real-world examples and graphics. Several important design software are examined, whether by personal practice or by literature research, depending on the availability of the software.Finally, the thesis include a case study, a 17" LCD computer monitor designed with a set of graphic programs including two-dimensional and three-dimensional packages.Keywords: Computers, industrial design methods, design software, computer aided design

    The Fifth NASA Symposium on VLSI Design

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    The fifth annual NASA Symposium on VLSI Design had 13 sessions including Radiation Effects, Architectures, Mixed Signal, Design Techniques, Fault Testing, Synthesis, Signal Processing, and other Featured Presentations. The symposium provides insights into developments in VLSI and digital systems which can be used to increase data systems performance. The presentations share insights into next generation advances that will serve as a basis for future VLSI design

    Techniques for the realization of ultra- reliable spaceborne computer Final report

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    Bibliography and new techniques for use of error correction and redundancy to improve reliability of spaceborne computer

    All-optical routing functionalities

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    Doutoramento em Engenharia EletrotécnicaAll-optical solutions for switching and routing packet-based traffic are crucial for realizing a truly transparent network. To meet the increasing requirements for higher bandwidth, such optical packet switched networks may require the implementation of digital functions in the physical layer. This scenario stimulated us to research and develop innovative high-speed all-optical storage memories, focusing mainly on bistables whose state switching is triggered by a pulsed clock signal. In clocked devices, a synchronization signal is responsible for controlling the enabling of the bistable. This thesis also presents novel solutions to implement optical logic gates, which are basic building blocks of any processing system and a fundamental element for the development of complex processing functionalities. Most of the proposed schemes developed in this work are based on SOA-MZI structures due to their inherent characteristics such as, high extinction ratio, high operation speed, high integration capability and compactness. We addressed the experimental implementation of an all-optical packet routing scheme, with contention resolution capability, using interconnected SOAMZIs. The impact on the system performance of the reminiscent power of the blocked packets, from the non ideal switching performed by the SOA-MZIs, was also assessed.As soluções totalmente óticas para a comutação e encaminhamento de pacotes de tráfego são cruciais para a realização de uma rede verdadeiramente transparente. Para atender às exigências crescentes de maior largura de banda, tais redes de comutação de pacotes óticos exigem a implementação de funções digitais na camada física. Este cenário estimulou-nos a investigar e a desenvolver memórias totalmente óticas, focando-nos principalmente na implementação de flip-flops óticos síncronos, cujo estado de comutação é accionado por um sinal de relógio. Esta tese também apresenta novas soluções para implementar portas lógicas óticas, visto estas serem um elemento fundamental para o desenvolvimento de funcionalidades complexas de processamento. A maioria dos esquemas propostos neste trabalho são baseados em estruturas interferométricas activas Mach-Zehnder (SOA-MZI) devido às suas características intrínsecas, nomeadamente, razão de extinção elevada bem como elevada capacidade de integração. A implementação experimental de um sistema de encaminhamento de pacotes totalmente ótico foi realizada usando cascatas de SOA-MZIs. O impacto da potência residual, devido à comutação não ideal dos SOA-MZIs, foi também analisado

    Intelligent autoreclosing for systems of high penetration of wind generation with real time modelling, development and deployment

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    COPYRIGHT Attention is drawn to the fact that copyright of this thesis rests with its author. A copy of this thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and they must not copy it or use material from it except as permitted by law or with the consent of the author. This thesis may be made available for consultation within the University Library and may be photocopied or lent to other libraries for the purposes of consultation. ii This thesis presents investigations into the effect of modern wind farms on grid side short circuits using extensive real time digital simulation. Particular reference is made to adaptive autoreclosing algorithms using artificial neural networks. A section of 132kV transmission grid in Scotland, including DFIG wind farms, is modelled on a real time digital simulator. An algorithm is then developed and tested using this model to show that this autoreclosing technique is feasible in systems with high penetration of wind generation. Although based on an existing technique, an important innovation is the use of two neural networks for the separate tasks of arc presence and extinction. The thesis also describes a low-cost, real time, relay development platform. Executive summary of key achievements- The effect of wind turbines on transmission line short circuit transients, with a comparison of the other significant parameters- Treatment of unbalanced faults and realistic arc modelling in this context- Feasibility studies on RTDS development of AdTAR using primary arcing and inter-circuit coupling- Development of robust AdSPAR autoreclosing algorithm using twin neural networks- A critical discussion of the use of AI in power system protection- A low cost, IEC 61850 compliant, real time relay development platfor
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