ppxscal/embedding_network huggingface dataset:
Clocking strategies for networks-on-chip
Authors: Johnny Öberg
Venue: Networks on chip (2003)

One of the main problems when designing today's ASICs, is to distribute a skew-free synchronous clock over the whole chip. A large part of the power is also consumed in the clock-tree, in some cases as much as 50% of the total power consumption of the chip, because the large wires in the clock-tree are switched often. To attack these two problems, several methods have been discussed in the research literature over the years, from the more obvious solution of using asynchronous communication between locally clocked regions (Globally Asynchronous Locally Synchronous - GALS) to more fancy methods like distributing a standing wave on the clock-wires across the whole chip. In this chapter, we go through different clocking methods that has been proposed over the years and are suitable for the NoC scheme as well as presenting a new and clever way of distributing a Quasi-synchronous, i.e., a perfectly synchronous, but not skew-less, clock across an entire NoC-chip.
Verification of Benchmarks 17 and 22 of the IFIP WG10.5 Benchmark Circuit Suite
Authors: Scott Hazelhurst, Carl J. H. Seger
Venue:  (1995)

This paper reports on the verification of two of the IFIP WG10.5 benchmarks --- the multiplier and systolic matrix multiplier. The circuit implementations are timed, detailed gate-level descriptions, and the specification is given using the temporal logic TLn, a quaternary-valued temporal logic. A practical, integrated theorem-proving/model checking system based on the compositional theory for TLn and symbolic trajectory evaluation is used to verify the circuits. A 64-bit version of multiplier circuit (Benchmark 17) containing approximately 28~000 gates takes about 18 minutes of computation time to verify. A 4 by 4, 32-bit version of the matrix multiplier (Benchmark 22) containing over 110~000 gates take about 170 minutes of computation time to verify. A significant timing error was discovered in this benchmark. Keywords: symbolic trajectory evaluation, benchmarks, compositional verification, temporal logic, theorem proving.
Design and Implementation of a Ferry-based Protocol Test System
Authors: Samuel T. Chanson, B. P. Lee, N. J. Parakh
Venue:  (1988)

The Ferry Clip concept can be used to build a Test System for protocol testing. By structuring the system into a set of modules, it is possible to minimize the effort required in using such a system to test different protocol implementations. In this paper we describe a method for structuring and implementing a Ferry Clip based Test System. Implementation issues encountered in building such a system under different environments are also discussed.
UCSC JAVA NETWORK COMPUTER PROCEDURES
Authors: Bruce R. Montague, Elizabeth A. Baldwin, Mike R. Allen
Venue:  (1996)

This document describes how to work with the UCSC Java and JN source. Although intended primarily for developers, this document is of use to anyone interested in the UCSC Java system or JN. This document primarily discusses operational procedures, such as how to write a UCSC Java application, and how to compile and build the system. Code internals are not described.
AHA! meets Auld Linky: integrating designed and free-form hypertext systems
Authors: David Millard, Hugh Davis, Mark Weal, Koen Aben, Paul De Bra
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

In this paper we present our efforts to integrate two adaptive hypermedia systems that take very different approaches. The Adaptive Hypermedia Architecture (AHA!) aims to establish a consistently organized, strictly designed form of hypertext while Auld Linky takes an open and potentially sculptural approach, producing more freeform, less deterministic hypertexts.We describe the difficulties in reconciling the two approaches. This leads us to draw a number of conclusions about the benefits and disadvantages of both and the concessions that are required to combine them successfully.
BOUNDS ON THE SAMPLE COMPLEXITY OF BAYESIAN LEARNING USINGINFORMATION THEORY AND THE VC DIMENSION
Authors: David Haussler, Michael Kearns, Robert Schapire
Venue:  (1992)

In this paper we study a Bayesian or average-case model of concept learning with a twofold goal: to provide more precise characterizations of learning curve (sample complexity) behavior that depend on properties of both the prior distribution over concepts and the sequence of instances seen by the learner, and to smoothly unite in a common framework the popular statistical physics and VC dimension theories of learning curves. To achieve this, we undertake a systematic investigation and comparison of two fundamental quantities in learning and information theory: the probability of an incorrect prediction for an optimal learning algorithm, and the Shannon information gain. This study leads to a new understanding of the sample complexity of learning in several existing models.
Terminating Parallel Simulations
Authors: Marc Abrams
Venue:  (1992)

This paper presents two different general solutions to the simulation termination problem for various simulation protocols and parallel architectures. Implementation of both solutions with conservative-synchronous, optimistic, and conservative-asynchronous simulation protocols as well as synchronous shared-memory, distributed, and asynchronous shared memory architectures is discussed.
Reflectance and Shape from a Rotating Object
Authors: Jiping Lu, Jim Little
Venue:  (1995)

In this paper we show that the reflectance function of a rotating object illuminated under a collinear light source (where the light source lies on or near the optical axis) can be estimated from the image sequence of the object and applied to surface recovery. We first calculate the 3D locations of some singular points from the image sequence, and extract the brightness values of these singular points during the object rotation to estimate the surface reflectance function. Then we use the estimated reflectance function for surface recovery from the images of the rotating object. Two subprocedures are used in surface recovery. The first subprocedure computes the depth around a point of known depth and surface orientation by using first-order Taylor series approximation. The other computes the surface orientation of a surface point from its image brightness values in the two different images by applying the estimated reflectance function. Starting from surface points of known depth values and surface orientations and iteratively applying the two subprocedures, the surface depth and orientation are recovered simultaneously over the whole object surface. The experimental results on real image sequences of both matte and specular surfaces show that the technique is feasible and robust.
HIERARCHICAL CLOCK ROUTING SCHEME FOR MULTI-CHIP MODULES BASED ON AREA PAD INTERCONNECTION
Authors: Qing Zhu, Wayne W Dai
Venue:  (1993)

The flip-chip technology for multi-chip modules provides area pads through solder bumps which are distributed over the entire chip surface. Clock skew has been identified as one of major limiting factors for high speed VLSI systems. We propose a two level clock routing scheme for a MCM-packaged VLSI system by making use of area pads and high connectivity of MCM substrate. The die is partitioned small isochronal regions with a area pad assigned for each bin. We implement the clock network of the MCM system in two levels. A global clock network with longer wires is routed on the MCM substrate which connects the clock source of the module to all clock area pads of dice. Inside every isochronous bin of a die, a delay-bounded clock tree is constructed from clock pad to clocked elements. Experimental results show this two level clock routing scheme dramatically reduces the clock wires and achieves high clocking performance of the whole MCM system.
Shrinkage of de Morgan Formulae under Restriction
Authors: M. S. Paterson, U. Zwick
Venue:  (1991)

It is shown that a random restriction leaving only a fraction epsilon of the input variables unassigned reduces the expected de Morgan formula size of the induced function by at least a factor of epsilon^((5-sqrt(3))/2)~=epsilon^1.63. (A de Morgan formula is a formula over the basis {/\, \/, ~}.) This improves a long-standing result of epsilon^1.5 by Subbotovskaya and a recent improvement to epsilon^((21-sqrt(73))/8)~=epsilon^1.55 by Nisan and Impagliazzo. The new exponent yields an increased lower bound of omega(n^((7-sqrt(3))/2-O(1)) for the de Morgan formula size of a function defined by Andreev. This is the largest lower bound known for a function in NP.
Relative to a Random Oracle, NP is not Small
Authors: S. Kautz, Per Bro Miltersen
Venue:  (1994)

Resource-bounded measure as originated by Lutz is an extension of classical measure theory which provides a probabilistic means of describing the relative sizes of complexity classes. Lutz has proposed the hypothesis that NP does not have measure zero in the class E2 = DTIME (2polynomial), meaning loosely that NP contains a non-negligible subset of exponential time. This hypothesis implies a strong separation of P from NP and is supported by a growing body of plausible consequences which are not known to follow from the weaker assertion P - NP. It is shown in this paper that relative to a random oracle, NP does not have measure zero in E2, improving the earlier result of Bennett and Gill that P - NP relative to a random oracle. Several new techniques are introduced; in particular the proof exploits the independence properties of algorithmically random sequences, and a strong independence result is shown: if A is an algorithmically random sequence and a subsequence A0 is chosen by means of a bounded Kolmogorov-Loveland place selection, then the sequence A1 of unselected bits is random relative to A0, i.e., A0 and A1 are independent. A bounded Kolmogorov-Loveland place selection is a very general type of recursive selection rule which may be interpreted as the sequence of oracle queries of a time-bounded Turing machine, so the methods used may be applicable to other questions involving random oracles.
Interactive Tools: Making UIMS Usable
Authors: Roger W. Ehrich, Deborah Hix, H. R Hartson
Venue:  (1986)

The earliest UIMS provided primarily run-time facilities for interface management and a set of programming tools for the development of application from the implementation requirements with which many tool designers have approached UIMS design, there are also methodological requirements that have been seriously neglected. One reason is that interface design methodology is poorly understood and rarely axiomatic. Nevertheless, it is important that we formulate methodological theories and provide UIMS with tools that support them. This paper proposes a storyboard metaphor for the conceptual design of human-computer interfaces.
Co-clustering Documents and Words Using Bipartite Spectral GraphPartitioning
Authors: Inderjit S. Dhillion
Venue:  (2001)

Both document clustering and word clustering are important and well-studied problems. By using the vector space model, a document collection may be represented as a word-document matrix. In this paper, we present the novel idea of modeling the document collection as a bipartite graph between documents and words. Using this model, we pose the clustering problem as a graph partitioning problein and give a new spectral algorithm that simultaneously yields a clustering of documents and words. This co-clustering algorithm uses the second left and right singular vectors of an appropriately scaled word-document matrix to yield good bipartitionings. In fact, it can be shown that these singular vectors give a real relaxation to the optimal solution of the graph bipartitioning problem. We present several experimental results to verify that the resulting co-clustering algorithm works well in practice and is robust in the presence of noise.
Numerical modeling of nailed soil walls in vertical excavation
Authors: Y. S. Hong, R. H. Chen, C. S. Wu
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

Among the methods for designing a nailed soil retaining wall, the most commonly used is the limit equilibrium method. However, procedures based on the limit equilibrium method remain some differences in considering the tensile force, the shear force, and the moment mobilized in the nails. A numerical analysis method for investigating the behavior of a nailed soil wall during and after excavation is presented in this paper. The analytical model consists of a nonlinear constitutive model for the soil, and constitutive models for the nails and shotcrete. The validity of the model is verified through comparison between the analytical results and the experimental observations for a full-scale nailed soil wall built in France. From this study, the analytical results indicate that the tensile force mobilized in the nail contributes the most important reinforcing effect, while the shear force developed in the nail is negligible. Results from parametric studies regarding the inclination and the stiffness of the nails are also presented.
Availability and Utility of Idle Memory in Workstation Clusters
Authors: Anurag Acharya, Sanjeev Setia
Venue:  (1998)

In this paper, we examine the availability and utility of idle memory in workstation clusters. We attempt to answer the following questions. First, how much of the total memory in a workstation cluster can be expected to be idle? This provides an estimate of the opportunity for hosting guest data. Second, how much memory can be expected to be idle on individual workstations? This helps determine the recruitment policy -- how much memory should be recruited on individual hosts? Third, what is the distribution of memory idle-times? This indicates how long guest data can be expected to survive; applications that access their data-sets frequently within the expected life-time of guest data are more likely to benefit from exploiting idle memory. Fourth, how much performance improvement can be achieved for off-the-shelf clusters without customizing the operating system and/or the processor firmware? Finally, how long and how frequently might a user have to wait to reclaim her machine if she volunteers to host guest pages on her machine? This helps answer the question of social acceptability. To answer the questions relating to the availability of idle memory, we have analyzed two-week long traces from two workstation pools with different sizes, locations, and patterns of use. To evaluate the expected benefits and costs, we have simulated five data-intensive applications (0.5 GB-5 GB) on these workstation pools.
Proofs on Safety for Untrusted Code
Authors: Grigore Rosu, Nathan Segerlind
Venue:  (1999)

Proof-carrying code is a technique that can be used to execute untrusted code safely. A code consumer specifies requirements and safety rules which define the safe behavior of a system, and a code producer packages each program with a formal proof that the program satisfies the requirements. The consumer uses a fast proof validator to check that the proof is correct, and hence the program is safe. In this report, we discuss applications for which proof-carrying code is appropriate, explain the mechanics of proof-carrying code, compare it with other security techniques and propose research directions for the method.
Topological Stochastic Grammars
Authors: Mike Alder, Christopher J.S. deSilva, Robert A. McLaughlin
Venue:  (1993)

This paper extends the paper Inference of Syntax for Point Sets and develops further the theory of topological grammars for syntactic pattern recognition.
A Redundant Arithmetic CORDIC System with a Unit Scale Factor
Authors: C. Clarke, Graham R. Nudd
Venue:  (1992)

The CORDIC algorithm for the calculation of trigonometric functions has traditionally suffered from two problems; speed, and the necessity to pre-scale the inputs. The speed problem is overcome to a large extent by the introduction of redundant number systems which have been shown by others. Here we show a new CORDIC system which has a unit scale factor that can be ignored. The unit scale factor is achieved by rotating the vector in 3 dimensional space in a manner which scales itUs projection onto the X-Y plane by the reciprocal of the overall scale factor. This new technique takes the same number of cycles as the standard CORDIC algorithm, with only marginally slower cycle times than the redundant system of Takagi [8]. The system is shown to be entirely compatible with redundant number system implementations of the CORDIC algorithm.
Evolution Properties of Space Curves
Authors: Farzin Mokhtarian
Venue:  (1988)

The Curvature Scale Space and Torsion Scale Space Images of a space curve are a multi-scale representation for that curve which satisfies several criteria for shape representation and is therefore a preferred representation method for space curves. \n The torsion scale space image of a space curve is computed by convolving a path-based parametric representation of the curve with Gaussian functions of varying widths, extracting the torsion zero-crossings of the convolved curves and combining them in a torsion scale space image of the curve. The curvature scale space image of the curve is computed similarly but curvature level-crossings are extracted instead. An evolved version of a space curve $\Gamma $ is obtained by convolving a parametric representation of that curve with a Gaussian function of variance $\sigma ^{2}$ and denoted by $\Gamma _{\sigma }$. The process of generating the ordered sequence of curves $ \{ \Gamma _{\sigma }\mid \sigma \geq 0\} $ is referred to as the {\it evolution} of $\Gamma $. \n A number of evolution properties of space curves are investigated in this paper. It is shown that the evolution of space curves is invariant under rotation, uniform scaling and translation of those curves. This property makes the representation suitable for recognition purposes. It is also shown that properties such as connectedness and closedness of a space curve are preserved during evolution of the curve and that the center of mass of a space curve remains the same as the curve evolves. Among other results is the fact that a space curve contained inside a simple, convex object, remains inside that object during evolution. \n The two main theorems of the paper examine a space curve during its evolution just before and just after the formation of a cusp point. It is shown that strong constraints on the shape of the curve in the neighborhood of the cusp point exist just before and just after the formation of that point.
Syntactic Pattern Classification of Moving Objects in a Domestic Environment
Authors: Sok G Lim, Christopher J.S. deSilva, Mike Alder
Venue:  (1993)

In this paper, we present a syntactic approach to classifying moving objects in a domestic environment such as human beings and curtains blown by the wind and external events such as moving tree branches. We use quadratic forms as our simple pattern primitives and the description of the objects (or patterns) is based on the relationships between the forms, which we call the UpWrite. The UpWrite process can be applied any number of times, to extract high level information such as strokes, and express them in a compact way suitable for classification.
Magnetohydrodynamic Flow Between a Solid Rotating Disk and a Porous Stationary Disk
Authors: Kishore S. Kumar, William I. Thacker, Layne T. Watson
Venue:  (1987)

In this paper we examine the flow of a conducting fluid between a solid rotating disk and a stationary porous disk with uniform section of fluid through the porous disk in the presence of a magnetic fiels. The equations of motion are solved using least change secant update quasi-Newton and modern root finding techniques. The fluid motion depends on the cross-flow Reynolds number, rotation Reynolds number and Hartmann number. The effects of the parameters on the flow field are presented graphically.
THE APPLICATION OF STOCHASTIC CONTEXT-FREE GRAMMARS TO FOLDING, ALIGNING AND MODELING HOMOLOGOUS RNA SEQUENCES
Authors: Y. Sakakibara, M. Brown, R. Hughey, I. S. Mian, K. Sjolander, R. Underwood, D. Haussler
Venue:  (1993)

Stochastic context-free grammars (SCFGs) are applied to the problems of folding, aligning and modeling families of homologous RNA sequences. SCFGs capture the sequences'' common primary and secondary structure and generalize the hidden Markov models (HMMs) used in related work on protein and DNA. The novel aspect of this work is that SCFG parameters are learned automatically from unaligned, unfolded training sequences. A generalization of the HMM forward-backward algorithm is introduced to do this. The new algorithm, Tree-Grammar EM, based on tree grammars and faster than the previously proposed SCFG inside-outside training algorithm, produced a model that we tested on the transfer RNA (tRNA) family. Results show that after having been trained on as few as 20 tRNA sequences from only two tRNA subfamilies (mitochondrial and cytoplasmic), the model can discern general tRNA from similar-length RNA sequences of other kinds, can find secondary structure of new tRNA sequences, and can produce multiple alignments of large sets of tRNA sequences. Our results suggest potential improvements in the alignments of the D- and T-domains in some mitochdondrial tRNAs that cannot be fitted into the canonical secondary structure.
Parallel Implementations of the Polynomial Preconditioned Conjugate GradientMethod
Authors: S. Thomas
Venue:  (1996)

This paper presents performance results for parallel implementations of the polynomial preconditioned conjugate gradient method on a Parsytec GC/PowerPlus-128 distributed memory parallel computer. The reduction in the number of iterations, total runtime and speedups to solve linear systems resulting from three-dimensional finite difference discretizations of Poisson''s equation with up to n=98,000 grid-points are investigated. With polynomial preconditioning the number of iterations and thus global inner products is reduced substantially at the expense of additional matrix by vector products. Global communication can be traded for local communication, which results in a superior scaling of the preconditioned algorithm on larger processor numbers. 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
Link Capacity Assignment in Dynamic Hierarchical Networks
Authors: Richard E. Nance, Robert L. Moose
Venue:  (1987)

The dynamic hierarchy, which is a generalization of the centralized, tree structured network, is introduced in this paper. First, a queueing network model of the dynamic hierarchy is formulated. Following the derivation of a network performance measure, probabilistic and heuristic assignment strategies are created. These strategies are compared through the use of analysis of variance procedures and preferred strategies are selected. It is found that a relatively simple heuristic strategy produces capacity assignments whose quality is comparable to that of the preferred probabilistic strategy.
Buckling behaviour of FRP thin-walled lipped channel members
Authors: N. Silvestre, D. Camotim
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

An extension of the "Generalised Beam Theory" (GBT) is employed to investigate the buckling behaviour of thin-walled lipped channel FRP columns, beams and beam-columns, fabricated by pultrusion and displaying a special kind of orthotropy. The GBT equations are used to identify the relevant (local and global) buckling modes and determine the corresponding bifurcation stress values. The influence of loading, material and geometrical parameters on the member buckling behaviour is assessed by means of a number of parametric studies. Special attention is paid to aspects related to the occurrence of local plate, distortional and flexural-distortional buckling modes.