We obtain the wave velocities and quality factors of clay-bearing sandstones as a function of por... more We obtain the wave velocities and quality factors of clay-bearing sandstones as a function of pore pressure, frequency and partial saturation. The model is based on a Biot-type three-phase theory that considers the coexistence of two solids (sand grains and clay particles) and a fluid mixture. Additional attenuation is described with the constant-Q model and viscodynamic functions to model the high-frequency behaviour. We apply a uniform gas/fluid mixing law that satisfies the Wood and Voigt averages at low and high frequencies, respectively. Pressure effects are accounted for by using an effective stress law. By fitting a permeability model of the Kozeny– Carman type to core data, the model is able to predict wave velocity and attenuation from seismic to ultrasonic frequencies, including the effects of partial saturation. Testing of the model with laboratory data shows good agreement between predictions and measurements.
In this paper 6.25Gbps and 5Gbps digital data transmission over copper cables up to 15m is invest... more In this paper 6.25Gbps and 5Gbps digital data transmission over copper cables up to 15m is investigated on a high-speed test board. Transmitter and receiver equalization techniques to compensate the non-ideal channel characteristic are evaluated. Signal integrity design and measurement implications of receiver side equalization are discussed.
This paper discusses an efficient statistical analysis methodology for system-level signal integr... more This paper discusses an efficient statistical analysis methodology for system-level signal integrity analysis. In the proposed method, statistical variations of the design and operational parameters are mapped to system performance through simulations based on orthogonal Taguchi arrays. Using the sensitivity functions derived from these simulations, statistical distributions of the performance measures are computed. The sensitivity functions and probability distributions of the design parameters are utilized as a diagnosis tool to estimate the design parameters of a system for a given measured performance. The statistical methodology is applied for design space exploration to improve system performance. For demonstrating the concept, a source synchronous memory bus and a peripheral input-output (I/O) bus have been analyzed under design and operational variations.
This paper describes the use of a genetic algorithm to optimize short bitstream inputs to produce... more This paper describes the use of a genetic algorithm to optimize short bitstream inputs to produce approximately worst case jitter in package simulation. Theory behind the algorithm and its applicability to a server memory subsystem simulation is summarized. Custom software utilizing this algorithm and an example of its use are presented.
The ever increasing power requirements of processors and application specific integrated circuits... more The ever increasing power requirements of processors and application specific integrated circuits (ASICs) impose stringent requirements on the design of power distribution networks (PDNs). This paper highlights a power analysis methodology and discusses the decoupling requirements of high performance components. The advantages of embedded package capacitors in core and I/O decoupling will be highlighted
We obtain the wave velocities and quality factors of clay-bearing sandstones as a function of por... more We obtain the wave velocities and quality factors of clay-bearing sandstones as a function of pore pressure, frequency and partial saturation. The model is based on a Biot-type three-phase theory that considers the coexistence of two solids (sand grains and clay particles) and a fluid mixture. Additional attenuation is described with the constant-Q model and viscodynamic functions to model the high-frequency behaviour. We apply a uniform gas/fluid mixing law that satisfies the Wood and Voigt averages at low and high frequencies, respectively. Pressure effects are accounted for by using an effective stress law. By fitting a permeability model of the Kozeny– Carman type to core data, the model is able to predict wave velocity and attenuation from seismic to ultrasonic frequencies, including the effects of partial saturation. Testing of the model with laboratory data shows good agreement between predictions and measurements.
In this paper 6.25Gbps and 5Gbps digital data transmission over copper cables up to 15m is invest... more In this paper 6.25Gbps and 5Gbps digital data transmission over copper cables up to 15m is investigated on a high-speed test board. Transmitter and receiver equalization techniques to compensate the non-ideal channel characteristic are evaluated. Signal integrity design and measurement implications of receiver side equalization are discussed.
This paper discusses an efficient statistical analysis methodology for system-level signal integr... more This paper discusses an efficient statistical analysis methodology for system-level signal integrity analysis. In the proposed method, statistical variations of the design and operational parameters are mapped to system performance through simulations based on orthogonal Taguchi arrays. Using the sensitivity functions derived from these simulations, statistical distributions of the performance measures are computed. The sensitivity functions and probability distributions of the design parameters are utilized as a diagnosis tool to estimate the design parameters of a system for a given measured performance. The statistical methodology is applied for design space exploration to improve system performance. For demonstrating the concept, a source synchronous memory bus and a peripheral input-output (I/O) bus have been analyzed under design and operational variations.
This paper describes the use of a genetic algorithm to optimize short bitstream inputs to produce... more This paper describes the use of a genetic algorithm to optimize short bitstream inputs to produce approximately worst case jitter in package simulation. Theory behind the algorithm and its applicability to a server memory subsystem simulation is summarized. Custom software utilizing this algorithm and an example of its use are presented.
The ever increasing power requirements of processors and application specific integrated circuits... more The ever increasing power requirements of processors and application specific integrated circuits (ASICs) impose stringent requirements on the design of power distribution networks (PDNs). This paper highlights a power analysis methodology and discusses the decoupling requirements of high performance components. The advantages of embedded package capacitors in core and I/O decoupling will be highlighted
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