ppxscal/embedding_network huggingface dataset:
Linear waste of best fit bin packing on skewed distributions
Authors: Claire Kenyon, Michael Mitzenmacher
Venue: Random Structures Algorithms (2002)

We prove that Best Fit bin packing has linear waste on the discrete distribution U{j, k} (where items are drawn uniformly from the set {1/k,2/k ..... j/k}) for sufficiently large k when j = αk and 0.66 ≥ α > 2/3. Our results extend to continuous skewed distributions, where items are drawn uniformly on [0, a], for 0.66 ≥ a > 2/3. This implies that the expected asymptotic performance ratio of Best Fit is strictly greater than 1 for these distributions.
Reconciling simplicity and realism in parallel disk modelsy
Authors: P. Sanders
Venue: Parallel Computing (2002)

For the design and analysis of algorithms that process huge data sets, a machine model is needed that handles parallel disks. There seems to be a dilemma between simple and flexible use of such a model and accurate modeling of details of the hardware. This paper explains how many aspects of this problem can be resolved. The programming model implements one large logical disk allowing concurrent access to arbitrary sets of variable size blocks. This model can be implemented efficiently on multiple independent disks even if zones with different speed, communication bottlenecks and failed disks are allowed. These results not only provide useful algorithmic tools but also imply a theoretical justification for studying external memory algorithms using simple abstract models.The algorithmic approach is random redundant placement of data and optimal scheduling of accesses. The analysis generalizes a previous analysis for simple abstract external memory models in several ways (higher efficiency, variable block sizes, more detailed disk model).
Finding Line Segments by Stick Growing
Authors: R. C. Nelson
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

A method is described for extracting lineal features from an image using extended local information to provide robustness and sensitivity. The method utilizes both gradient magnitude and direction information, and incorporates explicit lineal and end-stop terms. These terms are combined nonlinearly to produce an energy landscape in which local minima correspond to lineal features called sticks that can be represented as line segments. A hill climbing (stick-growing) process is used to find these minima. The method is compared to two others, and found to have improved gap-crossing characteristics.
Natural convection of fluid with variable viscosity from a heated vertical wavy surface
Authors: M. A. Hossain, S. Kabir, D. A. S. Rees
Venue: Zeitschrift f&uuml;r Angewandte Mathematik und Physik (ZAMP) (2002)

In the present paper, the effect of a temperature dependent viscosity on natural convection flow of viscous incompressible fluid from a vertical wavy surface has been investigated using an implicit finite difference method. Here we have focused our attention on the evaluation of the local skin-friction and the local Nusselt number. The governing parameters are the Prandtl number, Pr, ranging from 1 to 100, the amplitude of the waviness of the surface, α, ranging from 0.0 to 0.4 and the viscosity variation parameter, ε, ranging from 0.0 to 6.
The ECM Mark II: some observations on the rotor stepping
Authors: Geoff Sullivan
Venue: Cryptologia (2002)

The ECM Mark II has been described previously in Cryptologia [1]. An analysis of the motion of the rotors is presented here. A computer simulation of the ECM is available for download from the author's WWW Home Page.
Person Identification Using Multiple Cues
Authors: Roberto Brunelli, Daniele Falavigna
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1995)

This paper presents a person identification system based on acoustic and visual features. The system is organized as a set of non-homogeneous classifiers whose outputs are integrated after a normalization step. In particular, two classifiers based on acoustic features and three based on visual ones provide data for an integration module whose performance is evaluated. A novel technique for the integration of multiple classifiers at an hybrid rank/measurement level is introduced using HyperBF networks. Two different methods for the rejection of an unknown person are introduced. The performance of the integrated system is shown to be superior to that of the acoustic and visual subsystems. The resulting identification system can be used to log personal access and, with minor modifications, as an identity verification system.
3D Optical Interconnects for High-Speed Interchip and Interboard Communications
Authors: Ahmed Louri, Hongki Sung
Venue: Computer (1994)

Metal-based communications between subsystems and chips has become the limiting factor in high-speed computing. Maturing optics-based technologies offer advantages that may unplug this bottleneck. Optical interconnects offer high-speed computers key advantages over metal interconnects. These include (1) high spatial and temporal bandwidths, (2) high-speed transmission, (3) low crosstalk independent of data rates, and (4) high interconnect densities. Although faster device switching speeds will eventually be necessary for future massively parallel computing systems, the deciding factor in determining system performance and cost will be subsystem communications rather than device speed. Free-space optical interconnects, by virtue of their inherent parallelism, high data bandwidth, small size and power requirement, and relative freedom from mutual interference of signals, already show great promise in replacing metal interconnects to solve communication problems.
Fault-Tolerant Adaptive Scheduling for Embedded Real-Time Systems
Authors: Paul Richardson, Larry Sieh, Ali M. Elkateeb
Venue: IEEE Micro (2001)

This fault-tolerant algorithm uses a time-value scheduling approach to detect faults, sustain high processor utilization, and ensure timely execution of critical tasks.
New Directions at NASA Ames Research Center
Authors: Daniel Cooke, Scott Hamilton
Venue: Computer (2000)

Few people in the scientific community would dispute the role NASA has played in the advancement of aerospace and aerodynamic research in the 20th century. But to fulfill next-century goals of a manned mission to Mars and deep space exploration, NASA must drive the state of the art in computer science in the 21st century the way it has pushed advances in aerospace, rocketry, and aerodynamic research in the 20th century. However, NASA faces a wide array of difficult problems that-in order to be solved--require fundamental breakthroughs in virtually every area of computer science. During the past three years, NASA Ames Research Center (ARC) has led an effort to understand NASA's future Information Technology requirements and the concomitant research investments necessary to meet them. This study process has converged on three IT research cornerstones upon which NASA can build its future: automated reasoning for autonomous systems, human-centered computing, and high-performance computing and networking. This article focuses on several projects that embody these three research cornerstones.
Piecewise Self-Similar Solutions and a Numerical Scheme for Scalar Conservation Laws
Authors: Yong-Jung Kim
Venue: SIAM Journal on Numerical Analysis (2002)

The solution of the Riemann problem was a building block for general Cauchy problems in conservation laws. A Cauchy problem is approximated by a series of Riemann problems in many numerical schemes. But, since the structure of the Riemann solution holds locally in time only, and, furthermore, a Riemann solution is not piecewise constant in general, there are several fundamental issues in this approach such as the stability and the complexity of computation.In this article we introduce a new approach which is based on piecewise self-similar solutions. The scheme proposed in this article solves the problem without the time marching process. The approximation error enters in the step for the initial discretization only, which is given as a similarity summation of base functions. The complexity of the scheme is linear. Convergence to the entropy solution and the error estimate are shown. The mechanism of the scheme is introduced in detail together with several interesting properties of the scheme.
Existence of efficient points in vector optimization and generalized Bishop---Phelps theorem
Authors: K. F. Ng, X. Y. Zheng
Venue: Journal of Optimization Theory and Applications (2002)

In a set without linear structure equipped with a preorder, we give a general existence result for efficient points. In a topological vector space equipped with a partial order induced by a closed convex cone with a bounded base, we prove another kind of existence result for efficient points; this result does not depend on the Zorn lemma. As applications, we study a solution problem in vector optimization and generalize the Bishop--Phelps theorem to a topological vector space setting by showing that the B-support points of any sequentially complete closed subset A of a topological vector space E is dense in ∂A, where B is any bounded convex subset of E.
Dynamic Query-Based Debugging of Object-Oriented Programs
Authors: Raimondas Lencevicius, Urs Hölzle, Ambuj K. Singh
Venue: Automated Software Engineering (2003)

Program errors are hard to find because of the cause-effect gap between the instant when an error occurs and when the error becomes apparent to the programmer. Although debugging techniques such as conditional and data breakpoints help in finding errors in simple cases, they fail to effectively bridge the cause-effect gap in many situations. This paper proposes two debuggers that provide programmers with an instant error alert by continuously checking inter-object relationships while the debugged program is running. We call such tool a dynamic query-based debugger. To speed up dynamic query evaluation, our debugger implemented in portable Java uses a combination of program instrumentation, load-time code generation, query optimization, and incremental reevaluation. Experiments and a query cost model show that selection queries are efficient in most cases, while more costly join queries are practical when query evaluations are infrequent or query domains are small. To enable query-based debugging in the middle of program execution in a portable way, our debugger performs efficient Java class file instrumentation. We call such debugger an on-the-fly debugger. Though the on-the-fly debugger has a higher overhead than a dynamic query-based debugger, it offers additional interactive power and flexibility while maintaining complete portability.
On the Hierarchical Bayesian Approach to Image Restoration: Applications to Astronomical Images
Authors: R. Molina
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

In an image restoration problem one usually has two different kinds of information. In the first stage, one has knowledge about the structural form of the noise and local characteristics of the restoration. These noise and image models normally depend on unknown hyperparameters. The hierarchical Bayesian approach adds a second stage by putting a hyperprior on the hyperparameters, where information about those hyperparameters is included. In this work the author applies the hierarchical Bayesian approach to image restoration problems and compares it with other approaches in handling the estimation of the hyperparameters.
Comments on "An Optimal Shortest-Path Routing Policy for Network Computers with Regular Mesh-Connected Topologies"
Authors: T. Weller, B. Hajek
Venue: IEEE Transactions on Computers (1994)

S. Badr and P. Podar (1989) introduced a zig-zag routing policy and showed its optimality for shortest-path routing on square or infinite grid networks with independent link failures. This paper shows that, contrary to the claim of Badr and Podar, a zig-zag policy is not optimal for shortest-path routing on torus networks.
Acquiring 3-D Models from Sequences of Contours
Authors: J. Y. Zheng
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

This paper explores shape from contour for acquiring 3-D graphics models. In this method, a continuous sequence of images is taken as an object rotates. A smooth convex shape can be estimated instantaneously from its contour and by the first derivative of contour movement (trace of contour, or contour distribution with time). We also analyze shapes that do not satisfy the conditions of smoothness and visibility, which are indispensable for modeling an object. A region that does not expose as contour yields a nonsmoothness in the tracked contour movement. We can thus detect such a region by contour distribution filtering and extract its accurate location by computing the left and right derivatives of the distribution. This has not been studied previously. These unknown regions are obtained for further investigation using other visual cues. A general approach for building a geometrical object model using contours is then described. The entire process from silhouettes to a 3-D model is based local computation; this is promising for producing shapes in real time. Our direct goal is to establish 3-D graphics models of human faces for the growing needs of visual communications. We have obtained some good results.
A semi-implicit method for resolution of acoustic waves in low Mach number flows
Authors: Clifton Wall, Charles D. Pierce, Parviz Moin
Venue: Journal of Computational Physics (2002)

A semi-implicit numerical method for time accurate simulation of compressible flow is presented. By extending the low Mach number pressure correction method, a Helmholtz equation for pressure is obtained in the case of compressible flow. The method avoids the acoustic CFL limitation, allowing a time step restricted only by the convective velocity, resulting in significant efficiency gains. Use of a discretization that is centered in both time and space results in zero artificial damping of acoustic waves. The method is attractive for problems in which Mach numbers are low, and the acoustic waves of most interest are those having low frequency, such as acoustic combustion instabilities. Both of these characteristics suggest the use of time steps larger than those allowable by an acoustic CFL limitation. In some cases it may be desirable to include a small amount of numerical dissipation to eliminate oscillations due to small-wavelength, high-frequency, acoustic modes, which are not of interest; therefore, a provision for doing this in a controlled manner is included in the method. Results of the method for several model problems are presented, and the performance of the method in a large eddy simulation is examined.
Future Trends in Database Systems
Authors: M. Stonebraker
Venue: IEEE Transactions on Knowledge and Data Engineering (1989)

The author discusses the likely evolution of commercial data managers over the next several years. Topics to be covered include the following: why SQL (structured query language) has become a universal standard; who can benefit from SQL standardization; why the current SQL standard has no chance of lasting; why all database systems can be distributed soon; what new technologies are likely to be commercialized; and why vendor independence may be achievable.
A Model-Based Expert System for Digital System Design
Authors: Jung-Gen Wu, Yu Hen Hu, William P. -C. Ho, David Y. Y. Yun
Venue: IEEE Design Test (1990)

An expert system that generates digital system design from high-level specifications is described. It is called MBESDSD, short for model-based expert system for automated digital systems. The system is based on a three-phase model of digital system design. First, the high-level behavioral specifications are translated into a sequence of primitive behavioral operations. Next, these primitive operations are grouped to form intermediate-level behavioral functions. Finally, structural function modules are selected to implement these functions. The advantages of this model-based reasoning technique is that more design solutions are possible and the design is easier to optimize. The design of a popular peripheral device, the ART asynchronous receiver/transmitter, is used to demonstrate the proposed design process using MBESDSD.
On-The-Fly Reading of Entire Databases
Authors: Paul Ammann, Sushil Jajodia, Padmaja Mavuluri
Venue: IEEE Transactions on Knowledge and Data Engineering (1995)

A common database need is to obtain a global-read, which is a consistent read of an entire database. To avoid terminating normal system activity, and thus improve availability, we propose an on-the-fly algorithm that reads database entities incrementally and allows normal transactions to proceed concurrently. The algorithm assigns each entity a color based on whether the entity has been globally read, and a shade based on how normal transactions have accessed the entity. Serializability of execution histories is ensured by requiring normal transactions to pass both a color test and a shade test before being allowed to commit. Our algorithm improves on a color-only-based scheme from the literature; the color-only scheme does not guarantee serializability.
Mining a web citation database for author co-citation analysis
Authors: Yulan He, Siu Cheung Hui
Venue: Information Processing and Management: an International Journal (2002)

Author co-citation analysis (ACA) has been widely used in bibliometrics as an analytical method in analyzing the intellectual structure of science studies. It can be used to identify authors from the same or similar research fields. However, such analysis method relies heavily on statistical tools to perform the analysis and requires human interpretation. Web Citation Database is a data warehouse used for storing citation indices of Web publications.In this paper,we propose a mining process to automate the ACA based on the Web Citation Database. The mining process uses agglomerative hierarchical clustering (AHC) as the mining technique for author clustering and multidimensional scaling (MDS) for displaying author cluster maps. The clustering results and author cluster map have been incorporated into a citation-based retrieval system known as PubSearch to support author retrieval of Web publications.
Fuzzy-Logic-Based Analog Design Tools
Authors: Antonio J. Torralba, Jorge Chávez, L. g. Franquelo
Venue: IEEE Micro (1996)

Analog design is quite more difficult than digital design. As a consequence, most of the effort in analog design still relies on designer's experience. New ideas and methodologies are required to make a progress towards automating the analog design. Computational intelligence techniques, such as those based on fuzzy logic, have provided excellent results in those fields traditionally reserved to human experts. This article presents a collection of fuzzy logic-based tools which find an application in the three main design phases of the analog design: topology selection, modeling and optimization, and testing.
Integrating Linguistic Primitives in Learning Context-Dependent Representation
Authors: Samuel W. K. Chan
Venue: IEEE Transactions on Knowledge and Data Engineering (2001)

This paper presents an explicit connectionist-inspired, language learning model in which the process of settling on a particular interpretation for a sentence emerges from the interaction of a set of ¿soft¿ lexical, semantic, and syntactic primitives. We address how these distinct linguistic primitives can be encoded from different modular knowledge sources but strongly involved in an interactive processing in such a way as to make implicit linguistic information explicit. The learning of a quasi-logical form, called context-dependent representation, is inherently incremental and dynamical in such a way that every semantic interpretation will be related to what has already been presented in the context created by prior utterances. With the aid of the context-dependent representation, the capability of the language learning model in text understanding is strengthened. This approach also shows how the recursive and compositional role of a sentence as conveyed in the syntactic structure can be modeled in a neurobiologically motivated linguistics based on dynamical systems rather on combinatorial symbolic architecture. Experiments with more than 2,000 sentences in different languages illustrating the influences of the context-dependent representation on semantic interpretation, among other issues, are included.
Mapping and Repairing Embedded-Memory Defects
Authors: Lynn Youngs, Siva Paramanandam
Venue: IEEE Design Test (1997)

Yield is perhaps the single most important measure of manufacturing efficiency for large integrated circuits. To reduce product time-to-volume and accelerate continuous yield improvement, we have integrated memory test, defect mapping, and repair into the UltraSPARC microprocessor manufacturing flow.We use the UltraSPARC memory test port, together with standard memory test equipment and integrated software to detect, locate, and repair defects in the larger memory arrays. Pattern-recognized memory defect maps are collected for every chip manufactured, accelerating the understanding of defects and their causes. As part of the manufacturing process, we also program a unique identity into each chip that can be read electrically. In this article, we present the memory defect-mapping system that has been established and our use of that system to accelerate yield learning.
Some progress on the Aharoni-Korman conjecture
Authors: D. Duffs, T. Goddard
Venue: Discrete Mathematics (2002)

Aharoni and Korman (Order 9 (1992) 245) have conjectured that every ordered set without infinite antichains possesses a chain and a partition into antichains so that each part intersects the chain. Related to both Aharoni's extension of the König duality theorem and Dilworth's theorem, this is an important conjecture in the theory of infinite orders. It is verified for ordered sets of the form C × P, where C is a chain and P is finite, and for ordered sets with no infinite antichains and no infinite intervals.
A Unified Formalization of Four Shared-Memory Models
Authors: S. V. Adve, J. K. Aggarwal
Venue: IEEE Transactions on Parallel and Distributed Systems (1993)

The authors present a data-race-free-1, shared-memory model that unifies four earliermodels: weak ordering, release consistency (with sequentially consistent specialoperations), the VAX memory model, and data-race-free-0. Data-race-free-1 unifies themodels of weak ordering, release consistency, the VAX, and data-race-free-0 byformalizing the intuition that if programs synchronize explicitly and correctly, thensequential consistency can be guaranteed with high performance in a manner that retainsthe advantages of each of the four models. Data-race-free-1 expresses the programmer'sinterface more explicitly and formally than weak ordering and the VAX, and allows animplementation not allowed by weak ordering, release consistency, or data-race-free-0.The implementation proposal for data-race-free-1 differs from earlier implementations bypermitting the execution of all synchronization operations of a processor even whileprevious data operations of the processor are in progress. To ensure sequentialconsistency, two sychronizing processors exchange information to delay later operationsof the second processor that conflict with an incomplete data operation of the firstprocessor.
Performance Tradeoffs in Rings of Data-Driven Elements
Authors: A. Spray, S. Jones
Venue: IEEE Transactions on Computers (1993)

A method for maintaining causality within medium grained cellular based architectures is discussed. The strategy combines the benefits of data-driven communication with a hardware simplicity, latency and throughput rate approaching that of globally checked systolic arrays. It is shown that with this strategy higher throughput rates and lower latencies can be achieved by using slower processing elements.