ppxscal/embedding_network huggingface dataset:
Efficient Termination Detection for Loosely Synchronous Applications in Multicomputers
Authors: Chengzhong Xu, Francis C. M. Lau
Venue: IEEE Transactions on Parallel and Distributed Systems (1996)

We propose a simple algorithm which is based on edge-coloring of system graphs for termination detection of loosely synchronous computations. The proposed algorithm is fully symmetric in that all processors run syntactically identical code and can detect global termination at the same time. Under the 1-port communication model, the algorithm is optimal in terms of termination delay, the difference between the time when a global termination occurs and the time it is detected, in a number of structures¿chain, ring of even number of nodes, k-ary n-cube and k-ary n-mesh of low degree, where k is even; and near-optimal for other cases. The optimality analysis is based on results from a related problem, periodic gossiping in edge-colored graphs. This algorithm has been applied to some practical cases in which the overhead due to its execution is found to be insignificant.
Index array flattening through program transformation
Authors: Raja Das, Paul Havlak, Joel Saltz, Ken Kennedy
Venue: Proceedings of the 1995 ACM/IEEE conference on Supercomputing (CDROM) (1995)

This paper presents techniques for compiling loops with complex, indirect array accesses into loops whose array references have at most one level of indirection. The transformation allows prefetching of array indices for more efficient structuring of communication on distributed-memory machines. It can also improve performance on other architectures by enabling prefetching of data between levels of the memory hierarchy or exploitation of hardware support for vectorized gather/scatter. Our techniques are implemented in a compiler for Fortran D and execution speed improvements are given for multiprocessor and vector machines.
AIRMAIL: a link-layer protocol for wireless networks
Authors: Ender Ayanoglu, Sanjoy Paul, Thomas F. LaPorta, Krishan K. Sabnani, Richard D. Gitlin
Venue: Wireless Networks (1995)

This paper describes the design and performance of a link-layer protocol for indoor and outdoor wireless networks. The protocol is asymmetric to reduce the processing load at the mobile, reliability is established by a combination of automatic repeat request and forward error correction, and link-layer packets are transferred appropriately during handoffs. The protocol is named AIRMAIL (AsymmetrIc Reliable Mobile Access In Link-layer). The asymmetry is needed in the design because the mobile terminals have limited power and smaller processing capability than the base stations. The key ideas in the asymmetric protocol design consist of placing bulk of the intelligence in the base station as opposed to placing it symmetrically, in requiring the mobile terminal to combine several acknowledgments into a single acknowledgment to conserve power, and in designing the base stations to send periodic status messages, while making the acknowledgment from the mobile terminal event-driven. The asymmetry in the protocol design results in a one-third reduction of compiled code. The forward error correction technique incorporates three levels of channel coding which interact adaptively. The motivation for using a combination of forward error correction and link-layer retransmissions is to obtain better performance in terms of end-to-end throughput and latency by correcting errors in an unreliable wireless channel in addition to end-to-end correction rather than by correcting errors only by end-to-end retransmissions. The coding overhead is changed adaptively so that bandwidth expansion due to forward error correction is minimized. Integrity of the link during handoffs (in the face of mobility) is handled by window management and state transfer. The protocol has been implemented. Experimental performance results based on the implementation are presented.
The role of information-communication technology in a new organizational design
Authors: Bob Travica
Venue: Proceedings of conference on Organizational computing systems (1995)

Can information-communication technology enable new organizational designs, such as the networked organization and the adhocracy? An exploratory study into the accounting industry was undertaken in order to improve our understanding of this problem. On the basis of the literature of new designs a non-traditional organization model was developed in which information-communication technology was juxtaposed to a number of structural and cultural dimensions. The model was tested on a set of offices in the accounting industry and corroborated for the most part.
Bayesian regularization and pruning using a Laplace prior
Authors: Peter M. Williams
Venue: Neural Computation (1995)

Standard techniques for improved generalization from neural networks include weight decay and pruning. Weight decay has a Bayesian interpretation with the decay function corresponding to a prior over weights. The method of transformation groups and maximum entropy suggests a Laplace rather than a gaussian prior. After training, the weights then arrange themselves into two classes: (1) those with a common sensitivity to the data error and (2) those failing to achieve this sensitivity and that therefore vanish. Since the critical value is determined adaptively during training, pruning---in the sense of setting weights to exact zeros---becomes an automatic consequence of regularization alone. The count of free parameters is also reduced automatically as weights are pruned. A comparison is made with results of MacKay using the evidence framework and a gaussian regularizer.
Conjoining specifications
Authors: Martín Abadi, Leslie Lamport
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1995)

We show how to specify components of concurrent systems. The specification of a system is the conjunction of its components' specifications. Properties of the system are proved by reasoning about its components. We consider both the decomposition of a given system into parts, and the composition of given parts to form a system.
Developing special purpose simulators under Microsoft Windows
Authors: Kieran L. Coughlan, Paul J. Nolan
Venue: Proceedings of the 27th conference on Winter simulation (1995)

This paper discusses the benefits of using Microsoft Windows to construct special purpose simulators. Microsoft Windows has several features which makes the development of special purpose simulators easier than ever before. The development of a special purpose simulator for the Irish Electricity Supply Board (ESB) is described. This simulator models the network fault location and repair procedure and assists the ESB to find ways to reduce the length of power cuts. Visual Basic was used to design a user interface to a GPSS/H model and greatly assisted the development of the simulator.
Adaptable object migration: concept and implementation
Authors: Wolfgang Lux
Venue: ACM SIGOPS Operating Systems Review (1995)

Migration is one example of the insufficiently used potentials of distributed systems. Although migration can enhance the efficiency and the reliability of distributed systems, it is still rarely used. Two limitations contained in nearly all existing migration implementations prevent a widespread usage: migration is restricted to processes and the migration mechanism, i.e. the way state is transferred, is not adaptable to changing requirements.In our approach, migration is an operation provided by every object of any type. Triggered by higher level migration policies, the object migrates itself using an object-specific migration mechanism. Changing requirements are handled by higher level migration policies that adapt migration by exchanging the object's mechanisms.Adaptable migration was implemented within the BirliX operating system. Different migration mechanisms are accomplished by different meta objects, which can be attached to other objects. If an object has to be migrated, the meta object does the migration. Changing environmental requirements are handled by exchanging the meta object. As a result, each object has its own migration mechanism. The approach has been examined by implementing a couple of well-known migration mechanisms via meta objects. This paper describes the meta object implementation of the Charlotte migration mechanism.
Real-time multi-tasking in software synthesis for information processing systems
Authors: Filip Thoen, Marco Cornero, Gert Goossens, Hugo De Man
Venue: Proceedings of the 8th international symposium on System synthesis (1995)

Abstract: Software synthesis is a new approach which focuses on the support of embedded systems without the use of operating systems. Compared to traditional design practices, a better utilization of the available time and hardware resources can be achieved, because the static information provided by the system specification is fully exploited and an application-specific solution is automatically generated. On-going research on a software synthesis approach for real-time information processing systems is presented which starts from a concurrent process system specification and tries to automate the mapping of this description to a single processor. An internal representation model which is well-suited for the support of concurrency and timing constraints is proposed, together with flexible execution models for multi-tasking with real-time constraints. The method is illustrated on a personal terminal receiver demodulator for mobile satellite communication.
Advances in public-key certificate standards
Authors: Warwick Ford
Venue: ACM SIGSAC Review (1995)

To build effective public-key infrastructures, well-entrenched standards are essential because many different applications and different vendor products need to be supported and used. Standards for public-key certificate and certificate revocation list (CRL) formats are most important. The recognized standard in this area is ITU-T X.509, first published in 1988. In 1993, the Internet Privacy Enhanced Mail (PEM) proposals refined the use of X.509. However, more recently it has become apparent that there are several deficiencies in the X.509 formats and in the PEM refinements. Consequently, standards groups have undertaken an expedited activity to revise the X.509 formats by adding extensibility mechanisms and defining a set of standard extensions to satisfy a range of recognized needs. This paper outlines the status of this work as of mid-1995.
Missing the memory wall: the case for processor/memory integration
Authors: Ashley Saulsbury, Fong Pong, Andreas Nowatzyk
Venue: Proceedings of the 23rd annual international symposium on Computer architecture (1996)

Current high performance computer systems use complex, large superscalar CPUs that interface to the main memory through a hierarchy of caches and interconnect systems. These CPU-centric designs invest a lot of power and chip area to bridge the widening gap between CPU and main memory speeds. Yet, many large applications do not operate well on these systems and are limited by the memory subsystem performance.This paper argues for an integrated system approach that uses less-powerful CPUs that are tightly integrated with advanced memory technologies to build competitive systems with greatly reduced cost and complexity. Based on a design study using the next generation 0.25 micro;m, 256Mbit dynamic random-access memory (DRAM) process and on the analysis of existing machines, we show that processor memory integration can be used to build competitive, scalable and cost-effective MP systems.We present results from execution driven uni- and multi-processor simulations showing that the benefits of lower latency and higher bandwidth can compensate for the restrictions on the size and complexity of the integrated processor. In this system, small direct mapped instruction caches with long lines are very effective, as are column buffer data caches augmented with a victim cache.
Applications of inductive logic programming
Authors: Ivan Bratko, Stephen Muggleton
Venue: Communications of the ACM (1995)

Techniques of machine learning have been successfully applied to various problems [1, 12]. Most of these applications rely on attribute-based learning, exemplified by the induction of decision trees as in the program C4.5 [20]. Broadly speaking, attribute-based learning also includes such approaches to learning as neural networks and nearest neighbor techniques. The advantages of attribute-based learning are: relative simplicity, efficiency, and existence of effective techniques for handling noisy data. However, attribute-based learning is limited to non-relational descriptions of objects in the sense that the learned descriptions do not specify relations among the objects' parts. Attribute-based learning thus has two strong limitations: the background knowledge can be expressed in rather limited form, and the lack of relations makes the concept description language inappropriate for some domains.
An overview of hierarchical control flow graph models
Authors: Douglas G. Fritz, Robert G. Sargent
Venue: Proceedings of the 27th conference on Winter simulation (1995)

Hierarchical control flow graph models define a modeling paradigm for discrete event simulation modeling based upon hierarchical extensions to control flow graph models. Conceptually, models consist of a set of independent, encapsulated, concurrently operating model components where each component has its own thread of control and the components interact with each other solely via message passing. Two primary objectives for hierarchical control flow graph models are: (1) to facilitate model development by making it easier to develop, maintain, and reuse models and model elements and (2) to support the flexible and efficient execution of models. Hierarchical control flow graph models use two complementary types of hierarchical model specification structures, one to specify components and interconnections and the other to specify component behaviors.
An effective tool for learning the visual effects of rendering algorithms
Authors: Rosalee Wolfe, Andrew Sears
Venue: ACM SIGGRAPH Computer Graphics (1996)

Visual analysis is important to computer science students taking graphics courses. We created a tool called TERA to help students hone their visual analysis skills. We evaluated TERA's effectiveness by recording student performance on the visual identification portion of the midterm for two quarters. In the first class, students did not have access to TERA. In the second, they did. Students having access to TERA scored better on the visual identification portion of the midterm.
Object-oriented programming for embedded systems
Authors: Stuart Maclean, Sean Smith
Venue: ACM SIGPLAN Notices (1995)

Embedded systems are hard to program. Much of the effort is concentrated on processor-management code, effort totally unrelated to the application being built. Concurrent programming in embedded systems introduces even more problems --- mechanisms are needed to protect critical data areas. The application of object modeling to such mechanisms results in numerous benefits: fewer programming errors, enhanced portability and improved reuse. We present some simple in techniques for realising these benefits.
Flow-sensitive interprocedural constant propagation
Authors: Paul R. Carini, Michael Hind
Venue: ACM SIGPLAN Notices (1995)

We present a flow-sensitive interprocedural constant propagation algorithm, which supports recursion while only performing one flow-sensitive analysis of each procedure. We present experimental results which show that this method finds substantially more constants than previous methods and is efficient in practice. We introduce new metrics for evaluating interprocedural constant propagation algorithms which measure the number of interprocedural constant values that are propagated. We use these metrics to provide further experimental results for our algorithm.
The operating system kernel as a secure programmable machine
Authors: Dawson R. Engler, M. Frans Kaashoek, James W. O'Toole,  Jr.
Venue: ACM SIGOPS Operating Systems Review (1995)

To provide modularity and performance, operating system kernels should have only minimal embedded functionality. Today's operating systems are large, inefficient and, most importantly, inflexible. In our view, most operating system performance and flexibility problems can be eliminated simply by pushing the operating system interface lower. Our goal is to put abstractions traditionally implemented by the kernel out into user-space, where user-level libraries and servers abstract the exposed hardware resources. To achieve this goal, we have defined a new operating system structure, exokernel, that safely exports the resources defined by the underlying hardware. To enable applications to benefit from full hardware functionality and performance, they are allowed to download additions to the supervisor-mode execution environment. To guarantee that these extensions are safe, techniques such as code inspection, inlined cross-domain procedure calls, and secure languages are used. To test and evaluate exokernels and their customization techniques a prototype exokernel, Aegis, is being developed.
Object-oriented military simulation development and application
Authors: Ronald D. Painter
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The Department of Defense (DoD) is currently embracing object-oriented programming as a possible solution to problems that beset current simulation tools. The object paradigm, while extremely powerful, has associated costs that must be considered. To realize object-oriented programming benefits such as object reuse (sharing objects between simulations), data hiding (encapsulation), and code reuse and extension (polymorphism), the DoD modeling and simulation community must build objects to a set design standard. The immediate need facing the military simulation community is to agree on and build a framework for object-oriented simulations.
Trace and Eigenvalue Inequalities for Ordinary andHadamard Productsof Positive Semidefinite Hermitian Matrices
Authors: Bo-Ying Wang, Fuzhen Zhang
Venue: SIAM Journal on Matrix Analysis and Applications (1995)

Let $A$ and $B$ be $n\times n$ positive semidefinite Hermitian matrices, let $\alpha$ and $\beta$ be real numbers, let $\circ$ denote the Hadamard product of matrices, and let $A_{k}$ denote any $k\times k$ principal submatrix of $A.$ The following trace and eigenvalue inequalities are shown: $$ {\rm tr}(A\circ B)^\alpha \leq {\rm tr}(A^\alpha \circ B^\alpha ), \;\;\; \alpha \leq 0 \; \mbox{or} \; \alpha \geq 1,$$ $$ {\rm tr}(A\circ B)^\alpha \geq {\rm tr}(A^\alpha \circ B^\alpha ), \;\;\; 0\leq \alpha \leq 1,$$ $$ \lambda ^{1/\alpha }(A^\alpha \circ B^\alpha )\leq \lambda ^{1/\beta }(A^\beta \circ B^\beta ), \;\;\; \alpha \leq \beta , \alpha \beta \neq 0,$$ $$ \lambda ^{1/\alpha }[(A^\alpha )_{k}]\leq \lambda ^{1/\beta }[(A^\beta )_{k}], \;\;\; \alpha \leq \beta , \alpha \beta \neq 0.$$ The equalities corresponding to the inequalities above and the known inequalities $$ {\rm tr}(AB)^\alpha \leq {\rm tr}(A^\alpha B^\alpha ), \;\;\; |\alpha | \geq 1 ,$$ and $${\rm tr}(AB)^\alpha \geq {\rm tr}(A^\alpha B^\alpha ), \;\;\; |\alpha | \leq 1$$ are thoroughly discussed. Some applications are given.
Boundary Exact Controllability of Interface Problems with Singularities I: Addition of the Coefficients of Singularities
Authors: Serge Nicaise
Venue: SIAM Journal on Control and Optimization (1996)

We prove the exact controllability by boundary action of hyperbolic interface problems with singularities. The idea is to replace the classical space of controls with the space of their regular parts, which is augmented with the coefficents of singularities. This leads to a classical boundary control but with an internal control, which is a distribution with a support equal to the singular vertices.
Economical high performance parallel simulations of wind instruments
Authors: Panayotis A. Skordos
Venue: Proceedings of the 1995 ACM/IEEE conference on Supercomputing (CDROM) (1995)

A performance-price ratio of 2.2 Gflops per million dollars is demonstrated in simulations of wind instruments using a cluster of 20 non-dedicated Hewlett-Packard workstations and a shared-bus Ethernet network (the performance-price ratio is calculated assuming that the workstations were dedicated). The present simulations of wind instruments are based on the compressible Navier Stokes equations, and have only recently become possible through the use of parallel computing and through developments in numerical methods. The distributed simulation system has been built directly on top of UNIX and TCP/IP, and includes automatic process migration from busy workstations to free workstations.
PathFinder: a negotiation-based performance-driven router for FPGAs
Authors: Larry McMurchie, Carl Ebeling
Venue: Proceedings of the 1995 ACM third international symposium on Field-programmable gate arrays (1995)

Routing FPGAs is a challenging problem because of the relative scarcity of routing resources, both wires and connection points. This can lead either to slow implementations caused by long wiring paths that avoid congestion or a failure to route all signals. This paper presents PathFinder, a router that balances the goals of performance and routability. PathFinder uses an iterative algorithm that converges to a solution in which all signals are routed while achieving close to the optimal performance allowed by the placement. Routability is achieved by forcing signals to negotiate for a resource and thereby determine which signal needs the resource most. Delay is minimized by allowing the more critical signals a greater say in this negotiation. Because PathFinder requires only a directed graph to describe the architecture of routing resources, it adapts readily to a wide variety of FPGA architectures such as Triptych, Xilinx 3000 and mesh-connected arrays of FPGAs. The results of routing ISCAS benchmarks on the Triptych FPGA architecture show an average increase of only 4.5% in critical path delay over the optimum delay for a placement. Routes of ISCAS benchmarks on the Xilinx 3000 architecture show a greater completion rate than commercial tools, as well as 11% faster implementations.
Business process reengineering: emergence of a new research field
Authors: Thomas Barothy, Markus Peterhans, Kurt Bauknecht
Venue: ACM SIGOIS Bulletin (1995)

This paper provides an overview of published articles on Business Process Reengineering (BPR). Therefore it reports on an extensive literature review which identified BPR articles published in respected MIS outlets and/or written by three key proponents in the field. Besides manual examination of leading MIS journals and proceedings, the study incorporated a query in the ABI Inform Global reference database locating 552 items. The resulting 17 BPR articles are analyzed according to research approach and content. The analysis gives first insights into the development and state of BPR as a new research field. Based on this analysis we assess BPR and propose suggestions for further research.
Establishing a web site: some managerial issues
Authors: Merrill E. Warkentin, Lutfus Sayeed
Venue: ACM SIGICE Bulletin (1995)

The World Wide Web may become an important business tool to thousands of firms this year as it grows in size and capabilities. Many other firms wish to enter the age of cyberbusiness, but are unsure how to proceed. This paper addresses managerial and technical considerations when initiating a WWW project, with a focus on issues related to cost and control considerations, technical factors, security, web page design guidelines, standards, and trademark. This paper may serve as a guide to managers who choose to set up shop along the information superhighway.