ppxscal/embedding_network huggingface dataset:
Action graphs and coverings
Authors: Aleksander Malnic
Venue: Discrete Mathematics (2002)

An action graph is a combinatorial representation of a group acting on a set. Comparing two group actions by an epimorphism of actions induces a covering projection of the respective graphs. This simple observation generalizes and unifies many well-known results in graph theory, with applications ranging from the theory of maps on surfaces and group presentations to theoretical computer science, among others. Reconstruction of action graphs from smaller ones is considered, some results on lifting and projecting the equivariant group of automorphisms are proved, and a special case of the split-extension structure of lifted groups is studied. Action digraphs in connection with group presentations are also discussed.
Guest Editors' Introduction: Reliability and Safety of Real-Time Systems
Authors: William W. Everett, Shinichi Honiden
Venue: IEEE Software (1995)

Not a day goes by that the general public does not come intocontact with a real¿time system. As their numbers andimportance grow, so do the implications for software developers.
A Software Engineering Methodology for Rule-Based Systems
Authors: R. J. K. Jacob, J. N. Froscher
Venue: IEEE Transactions on Knowledge and Data Engineering (1990)

Current expert systems are typically difficult to change once they are built. The authors introduce a method for developing more easily maintainable rule-based expert systems, which is based on dividing the rules into groups and focusing attention on those facts that carry information between rules in different groups. They describe a new algorithm for grouping the rules of a knowledge base automatically and a notation set of software tools for the proposed method. The approach is supported by a study of the connectivity of rules and facts in rule-based systems; it is found that they indeed have the latent structure necessary for the programming methodology. Recent experimental results also support the approach. In contrast to the homogeneous way in which the facts of a rule-based system are usually viewed, this approach shows that certain facts are more important than others with regard to future modifications of the rules.
The essence of XML
Authors: Jérôme Siméon, Philip Wadler
Venue: ACM SIGPLAN Notices (2003)

The World-Wide Web Consortium (W3C) promotes XML and related standards, including XML Schema, XQuery, and XPath. This paper describes a formalization of XML Schema. A formal semantics based on these ideas is part of the official XQuery and XPath specification, one of the first uses of formal methods by a standards body. XML Schema features both named and structural types, with structure based on tree grammars. While structural types and matching have been studied in other work (notably XDuce, Relax NG, and a previous formalization of XML Schema), this is the first work to study the relation between named types and structural types, and the relation between matching and validation.
Design of an Adaptive Cache Coherence Protocol for Large Scale Multiprocessors
Authors: Q. Yang, G. Thangadurai, L. M. Bhuyan
Venue: IEEE Transactions on Parallel and Distributed Systems (1992)

A large scale, cache-based multiprocessor that is interconnected by a hierarchical network such as hierarchical buses or a multistage interconnection network (MIN) is considered. An adaptive cache coherence scheme for the system is proposed based on a hardware approach that handles multiple shared reads efficiently. The new protocol allows multiple copies of a shared data block in the hierarchical network, but minimizes the cache coherence overhead by dynamically partitioning the network into sharing and nonsharing regions based on program behavior. The new cache coherence scheme effectively utilizes the bandwidth of the hierarchical networks and exploits the locality properties of parallel algorithms. Simulation experiments have been carried out to analyze the performance of the new protocol. The simulation results show that the new protocol gives 15% to 30% performance improvement over some existing cache coherence schemes on similar systems for a wide range of workload parameters.
Multi-path continuous media streaming: what are the benefits?
Authors: L. Golubchik, J. C. S. Lui, T. F. Tung, A. L. H. Chow, W.-J. Lee, G. Franceschinis, C. Anglano
Venue: Performance Evaluation (2002)

Quality of service (QoS) in delivery of continuous media (CM) over the Internet is still relatively poor and inconsistent. Although many such applications can tolerate some degree of missing information, significant losses degrade an application's QoS. In this paper, we investigate the potential benefits of mitigating this problem through the exploitation of multiple paths existing in the network between a set of senders and a receiver of CM. Our focus in this work is on providing a fundamental understanding of the benefits of using multiple paths to deliver CM over best-effort wide-area networks. Specifically, we consider pre-recorded CM applications and use the following metrics in evaluating the performance of multi-path streaming as compared to single-path streaming: (a) data loss rate, (b) conditional error burst length distribution, and (c) lag1-autocorrelation. The results of this work can be used in guiding the design of multi-path CM systems streaming data over best-effort wide-area networks.
A Family of Parallel Prefix Algorithms Embedded in Networks
Authors: M. Takesue
Venue: IEEE Transactions on Parallel and Distributed Systems (1993)

This paper presents a family of algorithms for producing, from ( upsilon /sub 0/, upsilon/sub 1/, ..., upsilon /sub n-1/), all initial prefixes x/sub i/= upsilon /sub 0/ theta upsilon/sub 1/ theta ... theta upsilon /sub i/ (i=0, 1, ..., n-1) in parallel in interconnectionnetworks such as the omega network and the hypercube, where theta is an associativebinary operator. Each algorithm can be embedded in the switches and interconnections ofthe network, and can be executed in O((log/sub 2/ r+1) log/sub r/ n) time steps providedthat the network connecting n processors is constructed by using an r*r switch, and thatparallelism within as well as among individual switches is exploited. The objective of these algorithms is to attain a communication pattern that fits the topology of the network. One type of network can be made equivalent to, or can be embedded in, another type of network, so a family of algorithms can be derived from one basic algorithm. In the basic algorithm, every processor p/sub i/ upward multicasts upsilon /sub i/ to processors p/sub k/ (k=i+1, i+2, ..., n - 1). En route to p/sub i/, upsilon /sub j/ (j=0, 1, ..., i - 1) are combined in the switches to produce the (i - 1)th initial prefix x/sub i-1/ that is received by p/sub i/, which can then compute the ith initial prefix x/sub i/=x/sub i-1/ theta upsilon /sub i/.
Healthcare Data Warehousing and Quality Assurance
Authors: Donald J. Berndt, John W. Fisher, Alan R. Hevner, James Studnicki
Venue: Computer (2001)

Healthcare data warehousing presents unique challenges. The industry is rife with often incompatible medical standards and coding schemes that require careful translation. Healthcare data comes from many sources and is delivered in many forms, including published books, individual spreadsheets, and several tape or data formats. Results derived from a healthcare data warehouse must be delivered in accessible form to diverse stakeholders, including healthcare regulators, physicians, hospital administrators, consumers, community activists, and members of the popular press. The industry's widely decentralized and largely autonomous data collection efforts make data quality a significant challenge. Finally, the sensitivity of healthcare data makes privacy and security issues paramount. Healthcare data warehousing will make rigorous, quantitative information available to healthcare decision makers. The authors describe a fully functional healthcare data warehouse used to produce several reports for communities throughout Florida. Building on this work, they're actively pursuing a research agenda to enhance technical data warehousing capabilities while investigating innovative community and clinical healthcare applications.
Modelling fish behaviour
Authors: Kingsley Stephens, Binh Pham, Aster Wardhani
Venue: Proceedings of the 1st international conference on Computer graphics and interactive techniques in Australasia and South East Asia (2003)

This paper studies the problem of creating artificial fish for real-time interactive virtual worlds aimed at desktop environments with hardware 3D support. The artificial fish developed have the ability to move, sense, and think. Each fish is modelled with a Keyframed skeletal animated body, semi-physics based movement model, sensory abilities, internal motivations, a set of behaviour routines, and a behavioural selection mechanism. These features allow the fish to act autonomously using behavioural rules in response to sensory input from the environment and other fish. This autonomous ability enables definite behaviours to be described and observed in the fish that are not simply random, cyclic, or scripted.Excellent work has been previously done on modelling sophisticated artificial fish. The contribution of this paper is to focus on the practical modelling of fish for game production.
An integrated model for facility location and technology acquisition
Authors: Vedat Verter
Venue: Computers and Operations Research (2002)

This paper presents an analytical approach for simultaneous optimization of the facility location, capacity acquisition and technology selection decisions. The proposed approach can be useful when there is considerable interaction between these structural decisions, e.g., in global manufacturing companies. In these cases, a sequential optimization approach is bound to produce sub-optimal facility designs, and hence an integrated model is needed. We present a formal definition of the facility location and technology acquisition problem, and provide a basic model. We describe the analytical properties of the model, which led to the development of a solution procedure. We report on a set of experiments, and conclude that the computational performance of the proposed algorithm is quite satisfactory.
Survey of Low-Power Testing of VLSI Circuits
Authors: Patrick Girard
Venue: IEEE Design Test (2002)

The author reviews low-power testing techniques for VLSI circuits. He prefaces this with a discussion of power consumption that gives reasons for and consequences of increased power during test. The article ends with a discussion of the opportunity to use such techniques in varying situations.
OO-VHDL: Object-Oriented Extensions to VHDL
Authors: Sowmitri Swamy, Arthur Molin, Burt Covnot
Venue: Computer (1995)

Object-oriented approaches to software development have gained widespread acceptance as a way to manage design complexity and increase software reuse. These same needs are driving efforts to add object-oriented capabilities to hardware description languages (HDLs). VHDL (VHSIC hardware description language) was developed under the auspices of the US Department of Defense's Very High Speed Integrated Circuits (VHSIC) program in the 1980s. The current DoD effort, called RASSP (Rapid Prototyping of Application-Specific Signal Processors), is an ambitious undertaking to reduce, by a factor of four, the cost and time needed to design, upgrade, and replace embedded digital signal processors. To reach this goal, VHDL and its extensions must be used throughout the design process and at all levels from system to gate. VHDL has a number of constructs that have direct correlations in digital hardware; the most important are the component, which encapsulates a "black box" view of a piece of hardware, and the signal, which models a wire. Such constructs make VHDL suitable for developing detailed low-level models, but they make it difficult to write abstract high-level models. For system-level descriptions of behavior, a computation model more in line with software systems seems suitable. In this model, individual modules are reactive; that is, they respond only to a command/instruction or stimulus, communication is point-to-point, and the individual addressability of modules allows for temporary implicit communication pathways without the specificity of ports and interconnections. OO-VHDL, the object-oriented extension language of VHDL described in this article, supports both the VHDL computation model and the reactive computation model. The authors have implemented a preprocessor that translates OO-VHDL to VHDL and a debugging tool that maps VHDL statements into the OO-VHDL statements from which they were derived. Thus, modelers will be able to use OO-VHDL in current VHDL environments.
Automatic Programming for End Users: The TOAD System
Authors: F. Gomez, V. Wingate
Venue: IEEE Transactions on Knowledge and Data Engineering (1989)

An automatic programming system must embody not only a methodology for program synthesis, but also a formalism whereby problems can be specified by the user. The authors have designed TQ as a language for specifying programming problems and built a problem solver based on the methodology of classification problem solving. TQ is an informal specification language that allows a problem description to be written in nonprocedural terms by users who have no knowledge of programming. TOAD, the prototype system, demonstrates the feasibility and potential of the proposed approach and its suitability for end users. The authors compare their approach to those of other researchers in automatic programming and to the fourth generation languages.
Document Image Decoding Using Markov Source Models
Authors: G. E. Kopec, P. A. Chou
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

Document image decoding (DID) is a communication theory approach to document image recognition. In DID, a document recognition problem is viewed as consisting of three elements: an image generator, a noisy channel and an image decoder. A document image generator is a Markov source (stochastic finite-state automaton) that combines a message source with an imager. The message source produces a string of symbols, or text, that contains the information to be transmitted. The imager is modeled as a finite-state transducer that converts the 1D message string into an ideal 2D bitmap. The channel transforms the ideal image into a noisy observed image. The decoder estimates the message, given the observed image, by finding the a posteriori most probable path through the combined source and channel models using a Viterbi-like dynamic programming algorithm. The proposed approach is illustrated on the problem of decoding scanned telephone yellow pages to extract names and numbers from the listings. A finite-state model for yellow page columns was constructed and used to decode a database of scanned column images containing about 1100 individual listings.
Order Structure of Symbolic Assertion Objects
Authors: P. Brito
Venue: IEEE Transactions on Knowledge and Data Engineering (1994)

We study assertion objects that constitute a particular class of symbolic objects. Symbolic objects constitute a data analysis driven formalism, which can be compared to propositional calculus, but which is oriented toward the duality intension (characteristic properties) versus extension (set of all individuals verifying a given set of properties). The set of assertion objects is endowed with a partial order and a quasi-order. We focus on the property of completeness, which precisely expresses the duality intension-extension. The order structure of complete assertion objects is studied, using notions of lattice theory and Galois connection, and extending R. Wille's work (1982) to multiple-valued data. Two results are then obtained for particular cases.
A Source-to-Source Transformation for Increasing Rule-Based System Parallelism
Authors: A. J. Pasik
Venue: IEEE Transactions on Knowledge and Data Engineering (1992)

Rule-based systems have been hypothesized to contain only minimal parallelism. However, techniques to extract more parallelism from existing systems are being investigated. Among these methods, it is desirable to find those which balance the work being performed in parallel evenly among the rules, while decreasing the amount of work being performed sequentially in each cycle. The automatic transformation of creating constrained copies of culprit rules accomplishes both of the above goals. Rule-based systems are plagued by occasional rules which slow slow down the entire execution. These culprit rules require much more processing than others, causing other processors to idle while they continue to match. By creating constrained copies of culprit rules and distributing them to their own processors, more parallelism is achieved, as evidenced by increased speed up. This effect is shown to be specific to rule-based systems with certain characteristics. These characteristics are identified as being common within an important class of rule-based systems: expert database systems.
On the signal bounding problem in timing analysis
Authors: Jin Fuw Lee, D. L. Ostapko, Jeffery Soreff, C. K. Wong
Venue: Proceedings of the 2001 IEEE/ACM international conference on Computer-aided design (2001)

In this paper, we study the propagation of slew dependent bounding signals and the corresponding slew problem in static timing analysis. The selection of slew from the latest arriving signal, a commonly used strategy, may violate the rule of monotonic delay. Several methods for generating bounding signals to overcome this difficulty are described. The accuracy and monotonicity of each method is analyzed. These methods can be easily implemented in a static timer to improve the accuracy.
Declustering: A New Multiprocessor Scheduling Technique
Authors: G. C. Sih, E. A. Lee
Venue: IEEE Transactions on Parallel and Distributed Systems (1993)

The authors present a new compile-time scheduling heuristic called declustering, whichschedules acyclic precedence graphs that fit the synchronous data flow (SDF) modelonto multiprocessor architectures. This technique accounts for interprocessorcommunication (IPC) overheads and considers interconnection constraints in thearchitecture so that shared resource contention can be avoided. The algorithm initiallyinvokes a new clustering method that uses graph-analysis techniques to isolateparallelism instances. When constructing an initial set of clusters, this procedure explicitly addresses the tradeoff between exploiting parallelism and incurring communication cost. By hierarchically combining these clusters and then systematically decomposing this hierarchy, the declustering method exposes parallelism instances in order of importance and attains a cluster granularity that fits the characteristics of the architecture. It is shown that declustering retains the clustering advantage of avoiding IPC, yet overcomes the inflexibility associated with traditional clustering approaches.
Conformance Testing of VMEbus and Multibus II Products
Authors: Marcus Adams, Yi Qian, Jacek Tomaszunas, Josef Burtscheidt, Edgar Kaiser, Csaba Juhasz
Venue: IEEE Micro (1992)

A system for testing VMEbus and Multibus II products is described. The system is mainly automated to reduce costs and ensure impartiality. A test campaign is explained in the sense of a walk through the test system, in the way of a customer-such as a manufacturer, reseller, or original equipment manufacturer-would see it. The focus is on testing bus interfaces because it is more complex than testing backplanes.
A fast Algorithm for Optimum Syndrome Space Compression
Authors: C. -H. Tung, J. P. Robinson
Venue: IEEE Transactions on Computers (1988)

A procedure for multiple-output combinational circuits is presented that yields the optimum space compressor while using counting for time compression. The procedure is intended for the built-in selftest environment where output response data compression is appropriate. Optimum is defined as the minimum number of error patterns missed by the combination of space and time compression. The procedure uses the fast Walsh transform to determine the number of errors missed by each linear combination for all possible space-compression combinations. A illustrative example is included to show the effectiveness of the algorithm. A comparison between cases with and without space compression is included.
Control-Flow Speculation through Value Prediction
Authors: J. González, A. González
Venue: IEEE Transactions on Computers (2001)

In this paper, we introduce a new branch predictor that predicts the outcome of branches by predicting the value of their inputs and performing an early computation of their results according to the predicted values. The design of a hybrid predictor comprising the above branch predictor and a correlating branch predictor is presented. We also propose a new selector that chooses the most reliable prediction for each branch. This selector is based on the path followed to reach the branch. Results for immediate updates show significant misprediction rate reductions with respect to a conventional hybrid predictor for different size configurations. In addition, the proposed hybrid predictor with a size of 8 KB achieves the same accuracy as a conventional one of 64 KB. Performance evaluation for a dynamically scheduled superscalar processor, with realistic updates, shows a speed up of 8 percent despite its higher latency (up to four cycles).
Heterogeneous Transformation of Uncertainties of Propositions Among Inexact Reasoning Models
Authors: C. Zhang
Venue: IEEE Transactions on Knowledge and Data Engineering (1994)

Cooperation between different expert systems within a heterogeneous distributed expert system is essentially based on the transformations between the reasoning models built into the structures of the involved systems. The general criteria for a transformation between heterogeneous inexact reasoning models have been formulated. Using an algebraic structure of semigroup (with individual unit elements) of inexact reasoning models, the criteria are natural and easily satisfied by homomorphic mapping as an implementation. The criteria presented are too weak to ensure the existence of a unique mapping between the models concerned, but they are strong enough to guarantee reasonable transformations. These general considerations are illustrated using the example of three inexact reasoning models used by EMYCIN, PROSPECTOR, and MYCIN, where the homomorphic transformations among them are constructed and discussed.