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This thesis is missing page 95, copies of this thesis do not have the page. -Digitization Centre / A new high-level, high-order computer programming language designed to complement multi-processor, parallel computing systems is presented, These systems permit a high-order of operation by performing many instructions simultaneously, thus producing significant increases in computing The proposed language is so constructed as to give the user a free and natural format, to express problems which exhibit natural or inherent parallelism® In order to demonstrate some of the main features, a small subset of the language has been written, and implemented as a sequential simulation. In order to relate the language to hardware schemes, a parallel processing array computer is briefly examined. A core language to communicate with parallel computing systems may be constructed from the concepts developed. / Thesis / Master of Engineering (ME)

Traditional parallel methods for structural design do not scale well. This thesis discusses the application of massively scalable cellular automata (CA) techniques to structural design. There are two sets of CA rules, one used to propagate stresses and strains, and one to perform design analysis. These rules can be applied serially, periodically, or concurrently, and Jacobi or Gauss-Seidel style updating can be done. These options are compared with respect to convergence, speed, and stability. / Master of Science

Natural attenuation and biotransformation are processes that can potentially control the transport and enhance the remediation of contaminants in groundwater. It is necessary to develop computer simulations that not only model the physical transport (advection and dispersion) of contaminants, but that can also accurately depict chemical reactions and some of these more complex processes, in order to determine the type and extent of contaminant plumes and to analyze potential remediation strategies. Modeling these systems effectively is becoming possible with a growing understanding of the chemical and biological processes that occur in groundwater. However, more accurate and more involved models come with much higher memory and computational requirements. Parallel processing provides the computational resources needed to employ reactive transport simulations effectively and more efficiently. N2D-H2 is a FORTRAN code that simulates two-dimensional reactive solute transport in groundwater. More specifically, it simulates the biotransformation of nitrate into the end products of denitrification. A parallel version of the N2D-H2 code is developed using the Message-Passing Interface (MPI), a library of sequences and routines that can be called from FORTRAN programs. Using MPI to develop the parallel version of the code involves decomposing the computational domain among processors, defining the computational roles of each processor, and implementing the required communication between processors by using the message-passing procedures that allow the processors to exchange data. Several test problems are developed to analyze the performance of the parallel code. The test problems are used in the benchmarking procedure to demonstrate that the parallel code returns results identical to the sequential code. The CPU time required and the speedup achieved by running the simulation on parallel processors is presented for multiple test problems with varying physical processes and computational grid sizes. For a two-dimensional plume simulation of five solutes, with a finite difference grid of 490 nodes x 99 nodes, the total CPU time is decreased from 410 seconds on one processor to 220 seconds on two processors, and 75 seconds on ten processors. The speedup achieved gets closer to the ideal speedup as the problem size increases. Although the speedup observed with the parallel version of N2D-H2 is not 100% of the ideal speedup because of communication requirements, the parallel simulation demonstrates the benefits of parallel processing and the possibility of expansion that it provides for modeling reactive transport in groundwater. / Master of Science

The physical limitations of uniprocessors and the real-time requirements of numerous practical applications have made parallel processing an essential technology in military, industry and scientific research. In this dissertation, we investigate parallelizations of three practical applications using three parallel machine models. The algorithms are: Finitely inductive (FI) sequence processing is a pattern recognition technique used in many fields. We first propose four parallel FI algorithms on the EREW PRAM. The time complexity of the parallel factoring and following by bucket packing is O(sk^2 n/p), and they are optimal under some conditions. The parallel factoring and following by hashing requires O(sk^2 n/p) time when uniform hash functions are used and log(p) ≤ k n/p and pm ≈ n. Their speedup is proportional to the number processors used. For these results, s is the number of levels, k is the size of the antecedents and n is the length of the input sequence and p is the number of processors. We also describe algorithms for raster/vector conversion based on the scan model to handle block-like connected components of arbitrary geometrical shapes with multi-level nested dough nuts for the IES (image exploitation system). Both the parallel raster-to-vector algorithm and parallel vector-to-raster algorithm require O(log(n2)) or O(log2(n2)) time (depending on the sorting algorithms used) for images of size n2 using p = n2 processors. Not only is the DWT (discrete wavelet transforms) useful in data compression, but also has it potentials in signal processing, image processing, and graphics. Therefore, it is of great importance to investigate efficient parallelizations of the wavelet transforms. The time complexity of the parallel forward DWT on the parallel virtual machine with linear processor organization is O(((so+s1)mn)/p), where s0 and s1 are the lengths of the filters and p is the number of processors used. The time complexity of the inverse DWT is also O(((so+s1)mn)/p). If the processors are organized as a 2D array with PrawPcol processors, both the interleaved parallel DWT and IDWT have the time complexity of O(((so+s1)mn)/ProwPcol). We have parallelized three applications and achieved optimality or best-possible performances for each of the three applications over each of the chosen machine models. Future research will involve continued examination of parallel architectures for implementation of practical problems.

Thesis (M.S.)--Mississippi State University. Department of Computer Science. / Title from title screen. Includes bibliographical references.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / For research purposes on helicopter rotor acoustics a large data acquisition system called TEDAS (Transputer based Expandable Data Acquisition System) has been developed. The key features of this system are: unlimited expandability and sum data rate, local storage of data during operation, very simple analog anti aliasing filtering due to extensive digital filtering, and integrated computational power which scales with the number of channels. The sample rate is up to 50 kHz/channel, the resolution is 16 bit, 360 channels are realized now. TEDAS consists of blocks with 8 A/D converters which are controlled by one transputer T800. The size of the local memory is 4 Mbyte. Any number of blocks (IDAM = Intelligent Data Acquisition Module) can be combined to a complete system. Data preprocessing is done in parallel inside the IDAMs. As for 16 bit systems the analog antialiasing filtering becomes a dominant factor of the costs, delta sigma ADCs with oversampling and internal digital filtering are used. This produces an exact linear phase and a stop band rejection of -90 dB.