Computer Engineering Commons^™

Load And Communications Balancing On Multiprocessor Logic Simulation Engines, Ken Wong, Mark A. Franklin

All Computer Science and Engineering Research

The problem considered in this paper is to find an assignment of logic components to processors which will achieve logic simulation speed-ups approaching the ideal for large processor populations. This problem becomes particularly important when a significant portion of the speed-up expected from logic simulation engines is attributed to load sharing (as opposed to obtaining speed-up by employing specialized hardware to carry out specific tasks associated with the simulation process such as event queue manipulation or function evaluation). Our research considers this problem for a particular multiprocessor simulation architecture for which a performance model has bene developed. The model is …

Transaction Network: A Parallel Computation Model Based On Consume/Produce Paradigm, Takayuki Dan Kimura

All Computer Science and Engineering Research

This report introduces a new parallel computation model that is suitable for pursuit of large scale concurrency. Our goal is to develop a semantically clean paradigm for distributed computation with fine-grained parallelism. Our approach is to demote the notion of process as the key concept in organizing large scale parallel computation. We promote, instead, the notion of transaction, an anonymous atomic action void of internal state, as the basic element of computation. We propose to organize a computation as a network, called a transaction net, of databases connected by transactions. A transaction, when it is fired, consumes data objects from …

Advanced Communications Systems, Jonathan S. Turner

All Computer Science and Engineering Research

The Advanced Communication Systems Project is concerned with new communication technologies that can support a wide range of different communication applications in the context of large public networks. Communications networks in common use today have been tailored to specific applications and while they perform their assigned functions well, they are difficult to adapt to new uses. There currently are no general purpose networks, rather there are telephone networks, low-speed data networks and cable television networks. As new communications applications proliferate, it becomes clear that in the long term, a more flexible communications infrastructure will be needed. The Integrated Services Digital …

Software Tools For Performance Evaluation Of Concurrent Processing, Rodrogo A. Obando

Electrical & Computer Engineering Theses & Dissertations

The development and use of software tools for performance evaluation of concurrent processing is presented in this thesis. The particular concurrent processing architecture proposed by Stoughton and Mielke is investigated. The modelling of this architecture is based on Petri net theory and it can be studied making use of circuit theory. Computation of lower bounds for Time Between Outputs (TBO) and Time Between Input and Output (TBIO) can be accomplished by using principles of circuit theory, among others. This new modelling needs to be deeply evaluated and studied. This evaluation and study is accomplished with the tools developed and presented …

Prodb: An Experimental Generalized Database System User's Manual, Guillermo R. Simari

All Computer Science and Engineering Research

The following notes document in a succinct manner the use of the system PRODB. The system is still evolving and several new features are in the process of being added. PRODB is a prototype system that is being used as an exploration vehicle of the possible extensions to the relational model through logic programming. The system consists of a relational database system having a relational algebra type language as a query language. It is written in Prolog and it extends the capabilities of Prolog predicates with the relational algebra operators for handling the database structure. The database system currently provides …

Belief Maintenance Systems: Initial Prototype Specification, Roseanne M. Fulcomer, William E. Ball, John P. Tadlock

All Computer Science and Engineering Research

A fundamental need in future information systems is an effective method of accurately representing and monitoring dynamic, real-world situations inside a computer. Information is represented using an Extended Open World Assumption (EOWA), in which the data are explicitly true or false. Reasoning within the EOWA is done through the use of a dynamic dependency net which only represents those beliefs and justifications that are both currently valid and in current use. In this paper, we present definitions and uses of the EOWA and dynamic dependency net in our current research of developing a database with which we can use deductive …

Impact Of Automation On Process Control Decision-Making, Steven M. Miller, Susan R. Bereiter

Research Collection School Of Computing and Information Systems

This paper investigates changes in the process control of a vehicle assembly plant which had been modernized from a principally manual procedure to one that uses programmable automation extensively. Process control is defined as the information flow and decision-making required to perform basic process operations. We investigate the effects of implementing a computer-integrated production system on the amount and types of process control decision-making and on the distribution of process control decision-making between humans and machines. After automation, the emphasis on decisions regarding product quality specifications increased and the emphasis on decisions related to flexibility in handling a variety of …

A Unified Approach To Mixed-Mode Simulation, Roger D. Chamberlain, Mark A. Franklin

All Computer Science and Engineering Research

This paper presents a unified approach to mixed-mode simulation. It investigates the algorithms for both logic and circuit simulation, considering their similarities and differences, and a general framework is presented for integrating the two algorithms in uniform manner. The time advance mechanisms and component functional evaluations of the algorithms are show to be similar in nature, and mechanisms for the translation of information represented uniquely in the two algorithms are given. The resulting integrated algorithms is capable of performing mixed-mode simulation, where a circuit is partitioned into discrete and continuous regions, and each region is simulated at the appropriate level. …

Centre For Computer Aided Management: An Overview, V B Kaujalagi

IIMB Management Review

No abstract provided.

A Compiler For A Two-Dimensional Programming Language, Julie Wing Kam Choi

All Computer Science and Engineering Research

A visual programming language is presented. This language uses interactive graphics to convey notion such as subroutine, recursion, block structure, parallel and serial processing to school children. Currently the system is interpreter based. To overcome the inefficiency of the interpreter based system, a compiler is implemented for this language. This report gives an overview of the compiler and the details about the parser, semantic analyzer and the code generator. Finally, a performance comparison between the interpreter based system and the compiler based system is given.

Progressive Coding And Transmission Of Digital Diagnostic Pictures, Sharaf E. Elnahas, Kou-Hu Tsou, Jerome R. Cox, Rexford L. Hill, R. Gilbert Jost

All Computer Science and Engineering Research

In radiology, as a result if the increased utilization of digital imaging modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI), over a third of the images produced in a typical radiology department are currently in digital form, and this percentage is steadily increasing, Image compression provides a means for the economical storage and efficient transmission of these diagnostic pictures. The level of coding distortion than can be accepted for clinical diagnosis purposes is not yet well-defined. In this paper we introduce some constraints on the design of existing transform codes in order to achieve progressive image transmission …

Deterministic Linear Predictors For Bit Rate Improvement, Dhanvant H. Goradia

Electrical & Computer Engineering Theses & Dissertations

This thesis addresses the application of deterministic linear predictor s for telemetry based systems. Deterministic linear predictors are considered as a viable alternative to block transform coding in order to achieve bit rate reduction. A method of calculating the predictor coefficients of a deterministic linear predictor is presented. The system model is developed parametrically with respect to the bandwidth, polynomial order, signal class and predictor length. Two classes of signals, deterministic and random are analyzed and bounds on the performance of the deterministic linear predictor are established. A family of six pole Butterworth filters are used as presample filters in …

Show And Tell User's Manual, Peter Mclain, Takayuki Dan Kimura

All Computer Science and Engineering Research

The purpose of this report is to introduce essential features of the Show and Tell Language system to those computer users who are already familiar with some high-level programming language such as FORTRAN, BASIC or PASCAL. This manual is not intended for school children. Some familiarity with the Macintosh user interface and the MacPaint application program is assumed. It is also assumed that the Show and Tell application program disk and the Sample program are available to the reader. The basic programming concepts in Show and Tell are introduced in Chapter Three. The reader may find it easer to start …

A Systolic Parsing Algorithm For A Visual Programming Language, Adam W. Bojanczyk, Takayuki Dan Kimura

All Computer Science and Engineering Research

In this paper we consider a problem of parsing a two-dimensional visual programming language Show and Tell on a two-dimensional array of processors. A program in Show and Tell is a bit-mapped, two-dimensional pattern satisfying a certain set of grammatical rules. The pattern consists of partially ordered set of rectilinear boxes and arrows distributed over the space of nxn pixel area. The corresponding directed graph, the box graph, where boxes are nodes and arrows are directed edges, may not have a cycle in a Show and Tell program. The cycle detection is the most computationally intensive stage of the parsing …

An Exact Analysis For Efficient Computation Of Random-Pattern Testability In Combinational Circuits, Sharad C. Seth, Bhargab B. Bhattacharya, Vishwani Agrawal

School of Computing: Conference and Workshop Papers

Experimental evidence shows that low testability in a typical circuit is much more likely due to poor observability than poor controllability. Thus, from theoretical and practical standpoints, it is important to develop an accurate model for observability computation. One such model, in terms of supergates, is proposed in the first part of this paper thus complimenting our earlier work. It is now possible to obtain exact random-pattern testability for each line in a circuit.

The second part of the paper analyzes the supegate structure of a circuit from a graph theoretic viewpoint. Finding a supergate is related to determining the …

Lsim User Manual, Roger D. Chamberlain

All Computer Science and Engineering Research

Lsim is a gate/switch level digital logic similar. It enables users to model digital circuits both at the gate and switch level and incorporates features that support investigation of the simulation task itself. This user's manual describes the procedures used to specify a circuit to lsim and control the simulation of the circuit (i.e., specifying inputs vectors, running the simulation, and monitoring output signals).

Statistics On Logic Simulation, K. F. Wong, Mark A. Franklin, Roger D. Chamberlain, B. L. Shing

All Computer Science and Engineering Research

The high costs associated with logic simulation of large VLSI based systems have led to the need for new computer architectures tailored to the simulation task. Such architecture have the potential for significant speedups over standard software based logic simulators. Several commercial simulation engines have been produced to satisfy need in this area. To properly explore the space of alternative simulation architectures, data is required on the simulation process itself. This paper presents a framework for such data gathering activity by first examining possible sources of speedup in the logic simulation task, examining the sort of data needed in the …

Randomized Routing On Fat-Trees, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

Fat-trees are a class of routing networks for hardware-efficient parallel computation. This paper presents a randomized algorithm for routing messages on a fat-tree. The quality of the algorithm is measured in terms of the load factor of a set of messages to be routed, which is a lower bound on the time required to deliver the messages. We show that if a set of messages has load factor lambda on a fat-tree with n processors, the number of delivery cycles (routing attempts) that the algorithm requires is O(lambda+lgnlglgn) with probability 1-O(1/ …

Analog Computer Simulation With Automatic Scaling By Digital Computer, Mark Anthony Motter

Electrical & Computer Engineering Theses & Dissertations

A computer-aided design approach for the simplification of analog computer simulation is presented. The simulation configuration consists of an EAI 2000 analog computer with serial communications link to a PDP — 11/24 digital computer. Under control of the PDP-11, the analog simulations are realized with appropriate time and magnitude scaling which adjusts the range of the simulation coefficients and prevents overloads of the analog components. The analog computer hardware configuration accommodates both stable plants up to eighth order and closed-loop systems up to tenth order. Cascade compensation is provided for the closed-loop systems.

The plant may be described by either …

On The Probable Performance Of Graph Coloring Algorithms, Jonathan S. Turner

All Computer Science and Engineering Research

We define a natural probability distribution over the set of k-colorable graphs on n vertices and study the probable performance of several algorithms on graphs selected from this distribution. The main results are listed below. • We describe an algorithm to determine if a given n vertex graph is k-colorable, which runs in time O(n + m log k), where m is the number of edges. We show that this algorithm can successfully identify almost all random k-colorable graphs for constant or slowly growing values of k. • We show that an algorithm proposed by Brelas, and justified on experimental …

Collecting Data About Logic Simulation, Roger D. Chamberlain, Mark A. Franklin

All Computer Science and Engineering Research

Design of high performance hardware and software based gate-switch level logic simulators requires knowledge about the logic simulation process itself. Unfortunately, little data is publically available concerning key aspects of this process. An example of this is the lack of published empirical measurements relating to the time distribution of events generated by such simulators. This paper presents a gate-switch level logic simulator lsim which is oriented towards the collection of data about the simulation process. The basic components of lsim are reviewed, and its relevant data gathering facilities are discussed. An example is presented which illustrates the use of lsim …

Impacts Of Robotics And Flexible Manufacturing Technologies On Manufacturing Costs And Employment, Steven M. Miller

Research Collection School Of Computing and Information Systems

The issues analyzed in this paper are the extent to which unit costs and production labor requirements might be reduced in manufacturing industries if there is more widespread use of industrial robots and flexible systems. The analysis is reported in detail in Miller (1983). These issues are analyzed from two different perspectives. The technological focus of the first perspective is narrowly confined to the use of robotic manipulators. It is assumed that robotic manipulators will be “retrofitted” into existing production facilities without making major changes in the organization of production within the factory, other than modifying individual work stations so …

Block Encoding Of Speech Spectral Principal Components, James R. Holland Jr.

Electrical & Computer Engineering Theses & Dissertations

A Karhunen-Loeve series expansion was used to block encode speech spectral principal components as a function of time. Each of ten principal components was first obtained as a linear combination of 2© speech spectral band energies. Using a fixed block length of 10 frames (0.128 s), the K-L basis vectors were computed separately for various speakers for each principal component. In all cases the resulting basis vectors were essentially a set of discrete cosine basis vectors. Synthesis of speech from the block encoded parameters showed that very little information is lost with up to 70% data reduction. The block encoding …

Suboptimal Algorithms For Improvement Of Pipeline Through Insertion Of Delays, Sukhamoy Som

Electrical & Computer Engineering Theses & Dissertations

Pipelining is now widely used in the design of high speed processors in order to overcome the intrinsic speed limitations imposed by the technology. For a good performance and avoidance of internal conflicts, the concurrent operations within different subunits of a pipeline architecture should be properly scheduled This scheduling problem is known to be intrinsically difficult" and a member of the "NP complete class of problems. The aim of this thesis is to develop heuristic suboptimal algorithms whose execution time is a polynomial function of the number of items to be scheduled. Insertion of delay is used as a basic …

Ads Formal Semantics, Takayuki Kimura

All Computer Science and Engineering Research

Abstract Database System (ADS) is a data model developed for an enduring medical information system where frequent changes in the conceptual schema are anticipated and multi-level abstraction is required. The mechanism of abstraction in ADS is based on the abstraction operator of the lamba calculus. The formal semantics of a subset of the ADS model is presented using the denotational specification method.

Robotic Realities: Near Term Prospects And Problems, Robert U. Ayres, Steven M. Miller

Research Collection School Of Computing and Information Systems

Industrial robots are automation, but with a difference. Other machine tools are extensions of human capabilities, while robots are seen mainly as substitutes for human workers. Robots will find most of their industrial applications during the next decade or two in the metal-working sectors, where they will begin to displace semiskilled machine operatives in medium to large batch production operations. They cannot substitute for skilled machinists or other workers doing nonroutine jobs, or specialized, dedicated hard automation used in mass production. The current generation of robots, lacking sensory data processing and interpretation capabilities, can potentially replace up to 1.3 million …

Some Design Considerations For Picture Archiving And Communication Systems, J. R. Cox, G. J. Blaine, R. L. Hill, R. G. Jost, C. D. Shum

All Computer Science and Engineering Research

Design considerations for picture archiving and communication systems are reviewed with special emphasis on those issues that differ from conventional network architectures. Design equations for three layers of a picture network are developed and discussed in the context of preliminary estimates of the flow of digital images between a multiplicity of picture sources, picture archives and picture viewing stations. Discussions of differences from conventional networks focuses on the local nature of the net, the availability of a wide-band transmission media with low error rates, the relative costliness of network equipment capable of taking advantage of the wide-band transmission media and …

Interfacing The Sdk-85 With Common Laboratory Equipment, Thomas A. Boerjan

Graduate Research Papers

The-SDK-85 is a low-cost microcomputer trainer well-suited for entry and intermediate level programming and also interfacing. From it the fundamentals of digital electronics and computer programming can be taught at the high school and college level. The objectives of this paper are to learn:

1. The basic hardware required for a simple computer trainer.

2. The software necessary to do simple tasks.

3. How to interface the SDK-85 to common laboratory equipment.

4. How industry is using digital electronics.

5. Basic hardware and software troubleshooting • techniques.

6. Instructional methodology to be used with the SDK-85.

Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt

Chemistry & Biochemistry Theses & Dissertations

The PDP-11/10 minicomputer was interfaced to the Beckman 25 ultraviolet/visible spectrophotometer and this on-line computer system was applied to enzyme kinetics studies. This interface involved hardware equipment to locate, amplify, and transmit the analog signal to an analog-to-digital converter, and software to acquire and store the digital data. Data processing programs were used to calculate kinetic parameters and statistical information from the acquired data.

The Varian Cary 219 ultraviolet/visible spectrophotometer can be readily interfaced to the Apple II Plus microcomputer by hardware equipment which can be purchased from the manufacturer. Various software may also be purchased for use in enzyme …

Octal-Tree Spatial Sorting And Its Applications, Jeffrey L. Posdamer

All Computer Science and Engineering Research

An octal tree subdivision recursively divides a bounded three-dimensional volume into octanta about an internal division point. This scheme has been used to represent cellular or enumerated voxel models of solid objects. Given one or more sets of points sampled from the surface of a solid, an octal tree may be generated in which each leaf node contains m or less points. By specifying the tree traversal rule, the points are accessed in a sorted order. By defining m=3, a divide-and-conquer surface triangulation algorithm may be developed which does not require special sampling conditions (such as co-planarity) on subsets of …