156 research outputs found

    Long life testing of spare Mariner Venus '67 hardware

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    The faultless performance of the Mariner Venus '67 Power Conditioning Electronics (PCE) throughout six years of continuous operation in a simulated space environment is reported. Weekly functional tests supplemented by daily monitoring verified that the PCE equipment can perform to its intended functions for at least six years without apparent performance degradation. Performance throughout the test period was very stable, there are no circuit or redundancy improvements to be considered. When the equipment was examined after the test was completed, there was no evidence of any physical damage nor any difficulty in disconnecting the wiring connectors

    AC Electrokinetic Effect of V-Electrode Pattern on Microfluids

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    Electrokinetics has been used for guiding, pumping, and manipulating microfluidic particles for many years in the field of Biomedical, Microbiology, Chemistry, Medicine, and other fields of research, which makes it a ubiquitous tool for the multidisciplinary research on microfluidics. Between these two Alternating Current (AC) Electrokinetics have been proven to be more feasible for the researcher than the other one. In this research, we have investigated AC Electrokinetics and s effect on a new electrode configuration called V-electrode pattern. The V-electrode has been inspired and modified from the previous research work on the Orthogonal Electrode Pattern. In this research, this new electrode configuration has been analyzed using different types of setups, fabrication methods, and different fluidic conditions

    An investigation of model-based techniques for automotive electronic system development

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    Over the past decades, the adoption of electronic systems for the manufacturing of automotive vehicles has been exponentially popularized. This growth has been driven by the premium automobile sector where, presently, diverse electronic systems are used. These electronic systems include systems that control the engine, transmission, suspension and handling of a vehicle; air bag and other advanced restraint systems; comfort systems; security systems; entertainment and information (infotainment) systems. In systems terms, automotive embedded electronic systems can now be classified as a System of Systems (SoS). Automotive systems engineering requires a sustainable integration of new methods, development processes, and tools that are specifically adapted to the automotive domain. Model-based design is one potential methodology to carry out design, implement and manage such complex distributed systems, and their integration into one cohesive and reliable SoS to meet the challenges for the automotive industry. This research was conducted to investigate the model-based design of a 4Ă—4 Information System, within an automotive electronic SoS. Two distinct model-based approaches to the development of an automotive electronic system are discussed in this study. The first approach involves the use of the Systems Modelling Language (SysML) based tool ARTiSAN Studio for structural modelling, functional modelling and code generation. The second approach involves the use of the MATLAB based tools Simulink and Stateflow for functional modelling, and code generation. The results show that building the model in SysML by using ARTiSAN Studio provides a clearly structured visualization of the 4Ă—4 Information System from both structural and behavioural viewpoints of the system with relevant objects. SysML model facilitates a more comprehensive understanding of the system than the model built in Simulink/Stateflow. The Simulink/Stateflow model demonstrates its superior performance in producing high quality and better efficiency of C code for the automotive software delivery compared with the model built in ARTiSAN Studio. Furthermore, this Thesis also gets insight into an advanced function development approach based on the real-time simulation and animation for the 4Ă—4 Information System. Finally, the Thesis draws conclusions about how to make use of model-based design for the development of an automotive electronic SoS

    High Voltage and Nanoscale CMOS Integrated Circuits for Particle Physics and Quantum Computing

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    experimental studies in non-equilibrium physics

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    This work is a collection of three experiments aimed at studyingdifferent facets of non-equilibrium dynamics. Chapter I concernsstrongly compressible turbulence, which turns out to be verydifferent from incompressible turbulence. The focus is on thedispersion of contaminants in such a flow. This type of turbulencecan be studied, at very low mach number, by measuring the velocityfields of particles that float on a turbulently stirred body ofwater. It turns out that in the absence of incompressibility, theturbulence causes particles to cluster rather than to disperse.The implications of the observations are far reaching and includethe transport of pollutants on the oceans surface, phytoplanktongrowth, as well as industrial applications.Chapter II deals with the effects of polymer additives on dragreduction and turbulent suppression, a well-known phenomenon thatis not yet understood. In an attempt to simplify the problem, theeffects of a polymer additive were investigated in a vortex streetformed in a flowing soap film. Measurements suggest that anincrease in elongational viscosity is responsible for asubstantial reduction in periodic velocity fluctuations. Thisstudy also helps to illuminate the mechanism responsible forvortex separation in the wake of a bluff body.Chapter III describes an experiment designed to test a theoreticalapproach aimed at generalizing the classical fluctuationdissipation theorem (FDT). This theorem applies to systems drivenonly slightly away from thermal equilibrium, whereas ours, aliquid crystal undergoing electroconvection, is so stronglydriven, that the FDT does not apply. Both theory and experimentfocus on the flux in global power fluctuations. Physicallimitations did not permit a direct test of the theory, however itwas possible to establish several interesting characteristics ofthe system: the source of the fluctuations is the transient defectstructures that are generated when the system is driven hard. Itis found that the power fluctuations are spatially uncorrelated,but strongly correlated in time and even quasi-periodic

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 37)

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    Abstracts are provided for 76 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1990 through June 1990. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

    Applications for FPGA's on Nanosatellites

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    This thesis examines the feasibility of using a Field Programmable Gate Array (FPGA) based design on-board a CubeSat-sized nanosatellite. FPGAs are programmable logic devices that allow for the implementation of custom digital hardware on a single Integrated Circuit (IC). By using these FPGAs in spacecraft, more efficient processing can be done by moving the design onto hardware. A variety of different FPGA-based designs are looked at, including a Watchdog Timer (WDT), a Global Positioning System (GPS) receiver, and a camera interface

    Nd:YAG development for spaceborne laser ranging system

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    The results of the development of a unique modelocked laser device to be utilized in future NASA space-based, ultraprecision laser ranger systems are summarized. The engineering breadboard constructed proved the feasibility of the pump-pulsed, actively modelocked, PTM Q-switched Nd:YAG laser concept for the generation of subnanosecond pulses suitable for ultra-precision ranging. The laser breadboard also included a double-pass Nd:YAG amplifier and provision for a Type II KD*P frequency doubler. The specific technical accomplishment was the generation of single 150 psec, 20-mJ pulses at 10 pps at a wavelength of 1.064 micrometers with 25 dB suppression of pre-and post-pulses

    An investigation of model-based techniques for automotive electronic system development

    Get PDF
    Over the past decades, the adoption of electronic systems for the manufacturing of automotive vehicles has been exponentially popularized. This growth has been driven by the premium automobile sector where, presently, diverse electronic systems are used. These electronic systems include systems that control the engine, transmission, suspension and handling of a vehicle; air bag and other advanced restraint systems; comfort systems; security systems; entertainment and information (infotainment) systems. In systems terms, automotive embedded electronic systems can now be classified as a System of Systems (SoS). Automotive systems engineering requires a sustainable integration of new methods, development processes, and tools that are specifically adapted to the automotive domain. Model-based design is one potential methodology to carry out design, implement and manage such complex distributed systems, and their integration into one cohesive and reliable SoS to meet the challenges for the automotive industry. This research was conducted to investigate the model-based design of a 4Ă—4 Information System, within an automotive electronic SoS. Two distinct model-based approaches to the development of an automotive electronic system are discussed in this study. The first approach involves the use of the Systems Modelling Language (SysML) based tool ARTiSAN Studio for structural modelling, functional modelling and code generation. The second approach involves the use of the MATLAB based tools Simulink and Stateflow for functional modelling, and code generation. The results show that building the model in SysML by using ARTiSAN Studio provides a clearly structured visualization of the 4Ă—4 Information System from both structural and behavioural viewpoints of the system with relevant objects. SysML model facilitates a more comprehensive understanding of the system than the model built in Simulink/Stateflow. The Simulink/Stateflow model demonstrates its superior performance in producing high quality and better efficiency of C code for the automotive software delivery compared with the model built in ARTiSAN Studio. Furthermore, this Thesis also gets insight into an advanced function development approach based on the real-time simulation and animation for the 4Ă—4 Information System. Finally, the Thesis draws conclusions about how to make use of model-based design for the development of an automotive electronic SoS.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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