A system for the acquisition and processing of seismic data for refraction studies of the earths crust

The use of arrays of seismometers for seismic refraction measurements of crustal structure using explosions is reviewed, and the general factors to be considered in the design of equipment for the acquisition and processing of such data are discussed. The design and construction of a particular system using digital magnetic tape recording are described in detail. The three main modes of operation are the recording of ten channels of seismic information in the field, the replay in the laboratory of these ten channels to a multi-channel galvanometer oscillograph, and the transfer of the digital information to punched paper tape for input to a general purpose digital computer. The programmes that have been developed for handling this data on an Elliott 803 computer are described. The system was used during a crustal experiment using depth charges in September, 1%$. The performance during this test is evaluated. II - Stress systems in an inhomogeneous crust. The plane strain stress in an elastic half-space in which there are discrete variations in density over rectangular areas of the cross section is calculated by the double integration of .the result for a point force acting within an homogeneous elastic half-space. The resulting stress system is shown to be a valid solution of the equations of elasticity, and analytical results are derived for several special cases. The application of the theory of elasticity to crustal processes is reviewed, and numerical results are used to discuss the stress systems associated with isostatic compensation and with a crust of varying density

Reduction of perceptual redundancy for data compression of television signals

Imperial Users onl

Bandwidth compression of sonar displays

A major problem affecting the design of data compression systems is that of employing a buffer of limited size and at the same time prevent uncontrollable loss of data due to overflow. One method of alleviating this problem is to employ an adaptive compression algorithm. With this design approach when overflow is imminent the compression algorithm is degraded which effectively reduces the input rate to the buffer. A method is proposed here, where by using a recirculating register as the buffer the recirculating data controls the input rate and hence the performance of the system. The system has been analysed for a Poisson input process, and simulated using synthetic patterns similar to that encountered on sonar displays. The results indicate that this form of storage is quantitatively similar to random-access storage but qualitatively superior due to the random nature of the losses. An experimental system has been built using dynamic MOS shift registers for the store and a simple run-length coding procedure

Digital System Design - Use of Microcontroller

Embedded systems are today, widely deployed in just about every piece of machinery from toasters to spacecraft. Embedded system designers face many challenges. They are asked to produce increasingly complex systems using the latest technologies, but these technologies are changing faster than ever. They are asked to produce better quality designs with a shorter time-to-market. They are asked to implement increasingly complex functionality but more importantly to satisfy numerous other constraints. To achieve the current goals of design, the designer must be aware with such design constraints and more importantly, the factors that have a direct effect on them.One of the challenges facing embedded system designers is the selection of the optimum processor for the application in hand; single-purpose, general-purpose or application specific. Microcontrollers are one member of the family of the application specific processors.The book concentrates on the use of microcontroller as the embedded system?s processor, and how to use it in many embedded system applications. The book covers both the hardware and software aspects needed to design using microcontroller.The book is ideal for undergraduate students and also the engineers that are working in the field of digital system design.Contents• Preface;• Process design metrics;• A systems approach to digital system design;• Introduction to microcontrollers and microprocessors;• Instructions and Instruction sets;• Machine language and assembly language;• System memory; Timers, counters and watchdog timer;• Interfacing to local devices / peripherals;• Analogue data and the analogue I/O subsystem;• Multiprocessor communications;• Serial Communications and Network-based interfaces

Digital System Design - Use of Microcontroller

Embedded systems are today, widely deployed in just about every piece of machinery from toasters to spacecraft. Embedded system designers face many challenges. They are asked to produce increasingly complex systems using the latest technologies, but these technologies are changing faster than ever. They are asked to produce better quality designs with a shorter time-to-market. They are asked to implement increasingly complex functionality but more importantly to satisfy numerous other constraints. To achieve the current goals of design, the designer must be aware with such design constraints and more importantly, the factors that have a direct effect on them.One of the challenges facing embedded system designers is the selection of the optimum processor for the application in hand; single-purpose, general-purpose or application specific. Microcontrollers are one member of the family of the application specific processors.The book concentrates on the use of microcontroller as the embedded system?s processor, and how to use it in many embedded system applications. The book covers both the hardware and software aspects needed to design using microcontroller.The book is ideal for undergraduate students and also the engineers that are working in the field of digital system design.Contents• Preface;• Process design metrics;• A systems approach to digital system design;• Introduction to microcontrollers and microprocessors;• Instructions and Instruction sets;• Machine language and assembly language;• System memory; Timers, counters and watchdog timer;• Interfacing to local devices / peripherals;• Analogue data and the analogue I/O subsystem;• Multiprocessor communications;• Serial Communications and Network-based interfaces

A computer-aided design for digital filter implementation

Imperial Users onl

Analysis and correction of the helium speech effect by autoregressive signal processing

SIGLELD:D48902/84 / BLDSC - British Library Document Supply CentreGBUnited Kingdo