ppxscal/embedding_network huggingface dataset:
ISL: An Interval Logic for the Specification of Real-time Programs
Authors: A. Goswami, M. Bell, M. Joseph
Venue:  (1991)

ISL is a linear-time temporal logic for specifying properties of programs in execution intervals which are sequences of states. The end points of intervals are specified using instances of state predicates (or assertions) or time values. Abstract intervals, delimited by formulae over states in a computation, are used as the first step in constructing a timed specification. This is then transformed to incorporate timing, first by logical formulae and then using concrete time domains. Refinements are introduced to define time domains and timing properties and include refinement to programming constructs. We outline a way to specify resource limitations along with the functional and timing properties of programs. The specification method is illustrated with some examples. To be presented at the Symposium on Real-time and Fault-tolerant Systems, Nijmegen, The Netherlands, 8-10 January 1992.
Implementation of the Legion Library
Authors: Adam J. Ferrari, Michael J. Lewis, Charles L. Viles, Anh Nguyen-Tuong, Andrew Grimshaw
Venue:  (1996)

Legion is a multi-year effort to design and build scalable meta-computer software. Legion provides the software "glue" for seamless integration of distributed, heterogeneous hardware and software components. Much of this "glue" is provided in Legion''s run-time library. In this document we provide a detailed description of the implementation of the Legion run-time library. The library is designed and implemented as a layered, configurable software protocol stack. This design, coupled with an event-based mechanism for inter-layer communication, enables considerable flexibility and extensibility. In this document, we first present the library interface and show how the library can be used "as is", without internal modification. We then show how to modify or add functionality to the library. Finally, we provide qualitative descriptions of how the library could be extended to encompass programming styles and methods besides the object-oriented, macro data-flow style that is Legion''s initial target.
Visualizing and Modeling Categorical Time Series Data
Authors: Randy Ribler, Anup Mathur, Marc Abrams
Venue:  (1995)

Categorical time series data can not be effectively visualized and modeled using methods developed for ordinary data. The arbitrary mapping of categorical data to ordinal values can have a number of undesirable consequences. New techniques for visualizing and modeling categorical time series data are described, and examples are presented using computer and communications network traces.
Spirale Reversi: Reverse decoding of the Edgebreaker encoding
Authors: Martin Isenburg, Jack Snoeyink
Venue:  (1999)

We present a simple linear time algorithm for decoding Edgebreaker encoded triangle meshes in a single traversal. The Edgebreaker compression technique , introduced by Rossignac, encodes the topology of meshes homeomorphic to a sphere with a guaranteed 2 bits per triangle or less. The encoding algorithm visits every triangle of the mesh in a depth-first order. The original decoding algorithm recreates the triangles in the same order they have been visited by the encoding algorithm and exhibits a worst case time complexity of O(n^2). More recent work by Szymczak and Rossignac uses the same traversal order and improves the worst case to O(n). However, for meshes with handles multiple traversals are needed during both encoding and decoding. We introduce here a simpler decompression technique that performs a single traversal and recreates the triangles in reverse order.
A FIELD-PROGRAMMABLE PROTOTYPING BOARD: XC4000 BORG USER''S GUIDE
Authors: Pak K. Chan
Venue:  (1994)

The XC4000 BORG board is a PC-based prototyping board with two "user" FPGAs, two "routing" FPGAs, and a fifth FPGA which implements the glue logic for the PC bus. The BORG board is a reusable educational tool intended for a variety of classes; the BORG board, its toolset, and the reprogrammability of the FPGAs further reduce the time/cost of constructing prototypes using FPGAs. This report documents the design, implementation, and the use of BORG: A Field-Programmable Protyping Board.
Link Models for Networks with Dynamic Topologies
Authors: Robert L. Moose, Richard E. Nance
Venue:  (1987)

Dynamic hierarchical networks represent an architectural strategy for employing adaptive behavior in applications sensitive to highly variable external demands or uncertain internal conditions. The characteristics of such architectures are described, and the significance of adaptive capability is discussed. The necessity for assessing the tradeoffs between performance improvements (reduced and bounded message transmission time, increased throughput) and the added costs (reconfiguration delays, redundant links, etc.) leads to the use of complex queueing models. The assumptions underlying the general model are stated, and a class of applicable models (queues in random environments or RE-queues) is introduced. Matrix-geometric methods are reviewed in terms of their suitability for addressing several variations of a subclass of RE-queue models. Matrix-geometric techniques are considered to offer the greatest promise for obtaining usable results for assessing the cost/benefit tradeoffs.
DYNAMICS OF AN EXPLICIT RATE ALLOCATION ALGORITHM FOR AVAILABLE BIT-RATE (ABR) SERVICE IN ATM NETWORKS
Authors: Lampros Kalampoukas, Anujan Varma, K. K. Ramakrishnan
Venue:  (1995)

In this paper we study the performance of an explicit rate allocation algorithm for ATM Networks using the available bit-rate (ABR) class of service. We examine the behavior of ABR traffic with simple cell sources, and demonstrate that the allocation algorithm is fair and maintains network efficiency in a variety of network configurations. We also study the behavior of TCP/IP sources using ABR service in a network of switches employing the rate allocation algorithm; the results show substantial improvements in fairness and efficiency in comparison with the performance of TCP on an underlying datagram-based network. Even in a dynamic network configuration with frequent opening and closing of ABR connections, TCP connections were able to make sustained progress with a switch buffer size as small as 1 Kbyte, providing an average link utilization of approximately 60% of the attainable maximum. We also study the performance of ABR traffic in the presence of higher- priority variable bit-rate (VBR) video traffic and show that the overall system achieves high utilization with modest queue sizes in the switches, and the ABR flows adapt to the available rate in a fairly short interval. Scalability of the ABR service is an important criterion. We demonstrate the scalability of the rate allocation algorithm with respect to the number of connections by increasing the number of active connections with very long round-trip times by a factor of 13; this caused only a three times increase in the switch queue size, while still maintaining maximal link utilization.
A Robust Variable Order Facet Model for Image Data
Authors: Y. Mainguy, J. B. Birch, Layne T. Watson
Venue:  (1991)

It is a common practice in computer vision and image processing to convolve rectangular constant coefficient windows with digital images to perform local smoothing and derivative estimation for edge detection and other purposes. If all data points in each image window belong to the same statistical population, this practice is reasonable and fast. But, as is well known, constant coefficient window operators produce incorrect results if more than one statistical population is present within a window, e.g., if a gray level or gradient discontinuity is present. This paper shows one way to apply the theory of robust statistics to the data smoothing and derivative estimation problem. A robust window operator is demonstrated that preserves gray level and gradient discontinuities in digital images as it smooths and estimates derivatives.
TMM Lecture Materials
Authors: Kevin A. Mayo
Venue:  (1994)

TMM (Task Mapping Model) is a user-centered task analysis technique that uses situational evaluation to synthesize new user interface design requirements. This is a sample set of lecture materials for teaching TMM.
On Fitting Exponentials by Nonlinear Least Squares
Authors: James M. Varah
Venue:  (1982)

This paper is concerned with the problem of fitting discrete data, or a continuous function, by least squares using exponential functions. We examine the questions of uniqueness and sensitivity of the best least squares solution, and provide analytic and numerical examples showing the possible non-uniqueness, and extreme sensitivity of these solutions.
On Real-time Distributed Geographical Database Systems
Authors: Manhoi Choy, Mei Kwan, Hong V Leong
Venue:  (1993)

Advanced Traveler Information Systems (ATIS) under the Intelligent Vehicle Highway Systems (IVHS) context require efficient information retrieval and updating in a dynamic environment and at different geographical scales. Some problems in ATIS can be solved base on the functionalities provided by GIS systems. However, extra requirements such as real-time response are not readily met in existing GIS systems. We investigate the use of GIS-based systems for applications in ATIS and we propose a new system architecture based on existing GIS technology and distributed computing technology. Issues on data modeling, data representations, storage and retrieval, data aggregation, and parallel processing of on-line queries in the proposed GIS-based systems are discussed.
Large Deformations of a Whirling Elastic Cable
Authors: C. Y. Wang, Layne T. Watson
Venue:  (1990)

The large deformations of a whirling elastic cable is studied. The ends of the cable are hinged but otherwise free to translate along the rotational axis. The nonlinear governing equations depend on a rotation-elasticity parameter J. Bifurcation about the straight, axially rotating case occurs when J is greater than or equal to n(pi). Perturbation solutions about the bifurcation points and matched asymptotic solutions for large J are found to second order. Exact numerical solutions are obtained using quasi-Newton and homotopy methods.
Super-criticality revisited.
Authors: Paul F. Reynolds,  Jr.
Venue:  (1993)

Critical path analysis has been suggested as a technique for establishing a lower bound on the completion times of all parallel discrete event simulations (PDES). A protocol is super-critical if there is at least one simulation that can complete in less than the critical path time using that protocol. Previous studies have shown that several practical protocols are super-critical while others are not. We present a sufficient condition to demonstrate that a protocol is super-critical. Also, we show that a condition used in a previous study is not sufficient but necessary for super-criticality. It has been claimed that super-criticality requires independence of one or more messages (or states) on events in the logical past of those messages (states). We present an example which contradicts this claim and examine the implications of this contradiction on lower bounds.
On the Shape of a Set of Points in the Plane
Authors: H. Edelsbrunner, David G. Kirkpatrick, Raimund Seidel
Venue:  (1981)

A generalization of the convex hull of a finite set of points in the plane is introduced and analyzed. This generalization leads to a family of straight-line graphs, called ``shapes'''', which seem to capture the intuitive notion of ``fine shape'''' and ``crude shape'''' of point sets. .br Additionally, close relationships with Delaunay triangulations are revealed and, relying on these results, an optimal algorithm that constructs ``shapes'''' is developed.
Synchronization of Temporal Constructs in Distributed Multimedia Systems with Controlled Accuracy
Authors: Sang H. Son, Nipun Agarwal
Venue:  (1993)

With the inception of technology in communication networks such as ATM it will be pos- sible to run multimedia applications on future integrated networks. Synchronization of the related media data is one of the key characteristics of a multimedia system. In this paper we present a scheme for synchronization of multimedia data across a network where the accuracy of detecting asynchronization and predicting the future asynchrony is variable and can be tailored to the intended application. The protocol has been designed keeping in mind characteristics of ATM networks such as the absence of global synchronized clocks and utilizing features as the QOS promised by them. The multimedia data when sent across the network may also be stored at an intermediate node and later retrieved for dis- play. We extend the scheme and present a mechanism wherein synchronization of all the possible temporal constructs is supported and not restricted to the "in-parallel" construct which is only one of the thirteen possible temporal relations.
Strata: A Software Dynamic Translation Infrastructure
Authors: Kevin Scott, Jack Davidson
Venue:  (2001)

Software dynamic translation is the alteration of a running program to achieve a specific objective. For example, a dynamic optimizer uses software dynamic translation to modify a running program with the objective of making the program run faster. In addition to its demonstrated utility in dynamic optimizers, software dynamic translation also shows promise for producing applications that are adaptable, secure, and robust. In this paper, we describe the design and implementation of an extensible, retargetable infrastructure to facilitate research in applications of software dynamic translation technology. The infrastructure, called Strata, provides the software dynamic translator implementor with a virtual machine model that can be extended to implement specific software dynamic translation functionality. To illustrate the use of Strata to build client applications, the paper describes the Strata implementation of a two dynamic safety checkers and a dynamic instruction scheduler.
A Generic and Portable Image Processing Environment for Computer Vision
Authors: William S. Havens
Venue:  (1985)

Computer Vision research is flourishing although its growth has been hindered by the lack of good image processing systems. Existing systems are neither general nor portable despite various attempts at establishing standard image representations and software. Issues of hardware architecture and processing efficiency have frequently dominated system design. Often standard representations are primarily data formats for exchanging data among researchers working at affiliated laboratories using similar equipment. We argue that generality, portability and extensibility are the important criteria for developing image processing systems. The system described here, called {\em PIPS}, is based on these principles. An abstract image datatype is defined which is capable of representing a wide variety of imagery. The representation makes few assumptions about the spatial resolution, intensity resolution, or type of information contained in the image. A simple set of primitive operations are defined for direct and sequential access of images. These primitives are based on a bit stream access method that considers files and devices to be a long contiguous stream of bits that can be randomly read and written. Bit streams allow the word boundaries and file system architecture of the host computer system to be completely ignored and require only standard byte-wide direct-access I/O support. The standard image representation has encouraged the development of a library of portable generic image operators. These operators support interactive experimentation and make it easy to combine existing functions into new more complex operations. Finally, graphics device interfaces are defined in order to isolate graphics hardware from image processing algorithms. The system has been implemented under the Unix operating system. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
DETECTION OF MULTIPLE FAULTS IN TWO-DIMENSIONAL ILAs
Authors: Martine Schlag, F. J Ferguson
Venue:  (1995)

Two-dimensional arrays are suitable for VLSI implementation because of their regular structure and relative ease of test. We provide test sets proportional to the sum of the two dimensions of the array for a large class of cells, which allow us to test rows (or columns) of cells of the array independently. Previous research has found constant length test sets for array multipliers under the single faulty cell model if the array is modified and otherwise test sets are proportional to the number of cells. We can verify the full adder array of a combinational n X m multiplier in O(n+m) tests under the Multiple Faulty Cell (MFC) model. We show that no constant length test set exists for this array under the MFC model. The entire multiplier, including the AND gates which generate the summands, can be verified after applying the same modifications which make the multiplier C-testable under the single faulty cell model. Finally we show an error in the proof of a commonly accepted theorem involving testing two-dimensional arrays for multiple faults.(Supersedes ucsc-crl-90-69)
XTP Application Programming Interface
Authors: Rol Mechler, Author:
Venue:  (1995)

The Xpress Transport Protocol (XTP) is a lightweight transport protocol intended for high-speed networks. High-speed networks provide bandwidths of 100 Mbps and beyond, enabling a new class of applications (e.g., multimedia). So as not to be a bottleneck in the delivery of data, a transport protocol must provide high performance. Features of XTP which enhance performance include implicit connection setup, sender driven acknowledgement, selective retransmission, fixed format word aligned packet structures and suitability for parallel implementation. Since the new generation of applications may require a variety of services from the transport layer, a transport protocol designed for high-speed networks should also be flexible enough to provide these services. XTP provides the mechanisms to allow applications to tailor the functionality of the protocol to their individual needs. In particular, XTP provides flow control, rate control and error control, the use of each being optional and orthogonal to the others. This report describes an Application Programming Interface designedfor a multi-threaded implementation of XTP. The API allows all XTP parameters to be set from the application level, and addresses the issue of performance by providing a mechanism for zero copy transmission and reception of data.
AN IMPLEMENTATION MODEL FOR CONTEXTS AND NEGATION IN CONCEPTUAL GRAPHS
Authors: John Esch, Robert Levinson
Venue:  (1995)

An implementation model for a retrieval and inference system based on the theory of conceptual graphs is presented. Several hard issues related to the full implementation of the theory are taken up and solutions presented. The solutions attempt to exploit existing but not fully recognized symmetries in CG theory. These symmetries include those between formation and inference rules, AND and OR, positive and negative, copy and restrict, general and specific, etc. Topics taken up include the implementation of Sowa''s formation rules, the storage of a conceptual graph hierarchy involving contexts and negation as a conjunctive normal form (CNF) lattice, the extension of existing retrieval algorithms, such as Levinson''s Method III and UDS, to handle complex referents and nested contexts, the checking of consistency, and the definition of Peirce''s inference rules in terms of formation rules. A distinction is made between syntactic implication and semantic implication. The issues tackled in the paper lay the foundation for a full scale graph-based first-order logic theorem prover.
FLUTE: A Flexible Real-Time Data Management Architecture for Performance Guarantees
Authors: K. D. Kang, S. H. Son, J. A. Stankovic, T. F. Abdelzaher
Venue:  (2002)

Efficient real-time data management has become increasingly important as real-time applications become more sophisticated and data-intensive. In data-intensive real-time applications, e.g., online stock trading, agile manufacturing, sensor data fusion, and telecommunication network management, it is essential to execute transactions within their deadlines using fresh (temporally consistent) sensor data, which reflect the current real-world states. However, it is very challenging to meet this fundamental requirement due to potentially time-varying workloads and data access patterns in these applications. Also, user service requests and sensor updates can compete for system resources, thereby making it difficult to achieve guaranteed real-time database services in terms of both deadline miss ratio and data freshness. In this paper, we present a novel real-time data management architecture, which includes feedback control, admission control, and flexible update schemes, to enforce the deadline miss ratio of admitted user transactions to be below a certain threshold, e.g., 1%. At the same time, we maintain data freshness even in the presence of unpredictable workloads and access patterns. In a simulation study, we illustrate the applicability of our approach by showing that stringent performance specifications can be satisfied over a wide range of workloads and access patterns. We also show that our approach can significantly improve performance compared to baselines.
Probabilistic Solitude Detection on Rings of Known Size
Authors: Karl Abrahamson, Andrew Adler, Lisa Higham, David G. Kirkpatrick
Venue:  (1986)

Upper and lower bounds that match to within a constant factor are found for the expected bit complexity of a problem on asynchronous unidirectional rings of known size $n$, for algorithms that must reach a correct conclusion with probability at least $1 - \epsilon$ for some small preassigned $\epsilon \geq 0$. The problem is for a nonempty set of contenders to determine whether there is precisely one contender. If distributive termination is required, the expected bit complexity is \( \Theta (n \min ( \log \nu (n) + \sqrt{ \log \log (1 / \epsilon)}, \sqrt{ \log n}, \log \log (1 / \epsilon))) \), where $ \nu (n) $ is the least nondivisor of $n$. For nondistributive termination, $ \sqrt{\log \log (1 / \epsilon)} $ and $ \sqrt{\log n}$ are replaced by $\log \log \log (l/ \epsilon)$ and $\log \log n$ respectively. The lower bounds hold even for probabilistic algorithms that exhibit some nondeterministic features.
Data Distribution Concepts for Parallel Image Processing
Authors: Michael Nolle, Gerald Schreiber
Venue:  (1996)

Data distributions gained a considerable interest in the field of data parallel programming. In most cases they are key factors for the efficiency of the implementation. In this paper we analyze data distributions suited for parallel image processing and those defined by some of todays more popular parallel languages (HPF, Vienna Fortran, pC++) and libraries (ScaLAPACK). The majority of them belong to the class of bit permutations. These permutations can efficiently be realized on networks that are based on shuffle permutations. As a result we propose to widen the scope of data distributions tolerated by parallel languages and libraries towards classes of distributions. For the large class of the so called normal algorithms we demonstrate that it is possible to implement library functions that can handle a large subclass of distributions thereby avoiding redistributions. At the application level of programming data distributions are to be handled analogously to data types. The concepts introduced are implemented in the parallel image processing system PIPS, which is presented briefly.