ppxscal/embedding_network huggingface dataset:
STREAM TAPPING: A SYSTEM FOR IMPROVING EFFICIENCY ON A VIDEO-ON-DEMAND SERVER
Authors: Steven W. Carter, Darrell D.E. Long
Venue:  (1997)

Video-on-Demand (VOD) allows clients to view selected videos at any time, and it is essential for VOD servers to be run as efficiently as possible. Conventional VOD servers are not efficient; they dedicate a disk stream for each client, and this strategy quickly uses up all available streams. Other systems, such as batching, interval caching, and pyramid broadcasting, have been studied. These systems make more efficient use of the VOD server''s disk streams. In this report we present a new VOD system called stream tapping. Stream tapping allows clients to aggressively "tap" into any disk streams on the VOD server that are reading data the client can use. This can be accomplished through the use of a small buffer -- as small as 115 MB for MPEG-1 encoding -- on the client''s set-top box, and it can save over 80% of the disk bandwidth used by a conventional system. This report includes a description and analysis of the stream tapping system, and comparisons between it and other efficiency-improving systems.
Propagation of Constants and Assertions
Authors: Alexander Sakharov
Venue: ACM SIGPLAN Notices (1994)

Constant propagation is a well-known data flow analysis time calculations and deletion of unreachable code. In this paper, constant propagation is generalized to allow propagation of a wider class of assertions. Along this class includes controlling expressions of assignments. The problem of propagating these assertions monotone data flow analysis frameworks. Propagation of the assertions enables additional deletion of assignments and redirection of control flow. 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
Successive Approximation in Parallel Graph Algorithms
Authors: Donald S. Fussell, Ramakrishna Thurimella
Venue:  (1988)

The notion of successive approximation is introduced in the context of parallel graph algorithms. The implementation of graph algorithms on Leighton''s mesh of trees network model is considered. The implementations that have appeared so far in the literature are relatively straightforward. A common characteristic of these algorithms is that, in each iteration, for each vertex v, at most one edge is selected from the edges incident on v. This selection is based purely on local information such as the weights of the edges incident v or the labels of the neighboring vertices of v etc. As this sort of information appears on the same row of a mesh, these algorithms lend themselves to a direct implementation. In this paper we present an implementation of the open ear decomposition algorithm of Maon, Schieber and Vishkin. Some applications of open ear decomposition include parallel planarity testing, triconnectivity and 4-connectivity testing. This algorithm is different from the other algorithms considered for implementation on a mesh of trees in that a direct implementation is ruled out due to the communication problems posed by the network. Our implementation uses a technique of successive approximation. The process starts by finding an open ear decomposition of a subgraph of at most 2n edges: the edges of two edge-disjoint forests of G. Each subsequent iteration uses the decomposition from the previous step to obtain an open ear decomposition of an enlarged subgraph. This enlarged subgraph consists of the edges that received an ear label in the previous step together with at least as many new ones. Therefore the process converges in O(logn) iterations. The decomposition algorithm for each iteration can be distributed on the network. The whole algorithm takes O(log839n) time using O(n/lognxn/logn) processors. Assuming adjacency matrix representation of the graph, the achieved speedup is O(logn) factor off the optimal, which is the best known.
TESTING FOR OPENS IN DIGITAL CMOS CIRCUITS (Ph.D. Thesis)
Authors: Haluk Konuk
Venue:  (1996)

Shorts and opens are the most common types of defects in today''s CMOS integrated circuits. This dissertation focuses on opens that occur in transistor drain/source connections and in the interconnect wiring. Compared to prior research, a very efficient and the most accurate, in terms of taking all test invalidation mechanisms into account, fault simulator for opens in drain/source connections is presented. Results show the individual contributions of different test invalidation mechanisms. How interconnect opens can cause oscillations and sequential behavior is demonstrated for the first time. Necessary conditions for such behavior are likely to occur in many interconnect opens. A fault simulation algorithm for interconnect opens, which takes into account all known factors that can affect the behavior of an interconnect open, is presented. The estimated run-time for this algorithm is a constant multiple of the run-time required for stuck-at-fault simulation. Empirical evidence from test chips, which contain various floating-gate transistor structures, shows for the first time that the die surface can become a factor in determining the behavior of a floating wire created by an interconnect open.
Financial benchmarking using self-organizing maps studying the international pulp and paper industry
Authors: Tomas Eklund, Barbro Back, Hannu Vanharanta, Ari Visa
Venue: Data mining: opportunities and challenges (2003)

Performing financial benchmarks in today's information-rich society can be a daunting task. With the evolution of the Internet, access to massive amounts of financial data, typically in the form of financial statements, is widespread. Managers and stakeholders are in need of a tool that allows them to quickly and accurately analyze these data. An emerging technique that may be suited for this application is the self-organizing map. The purpose of this study was to evaluate the performance of self-organizing maps for the purpose of financial benchmarking of international pulp and paper companies. For the study, financial data in the form of seven financial ratios were collected, using the Internet as the primary source of information. A total of 77 companies and six regional averages were included in the study. The time frame of the study was the period 1995-2000. A number of benchmarks were performed, and the results were analyzed based on information contained in the annual reports. The results of the study indicate that self-organizing maps can be feasible tools for the financial benchmarking of large amounts of financial data.
HYPERCUTS: A Decision Tree Based Algorithm for Fast Packet Classification
Authors: Sumeet Singh, George Varghese, Florin Baboescu
Venue:  (2002)

A classifier consists of a set of rules for classifying packets based on header fields. Because core routers can have fairly large (e.g., 2000 rule) database and must use limited SRAM to meet OC-768 speeds, the best existing classification algorithms (RFC, HiCuts, ABV) are precluded because of the large amount of memory they need. Thus the general belief is that hardware solutions like CAMs are needed, despite the amount of board area and power they consume. In this paper we provide an algorithm based on a fast search structure capable of providing search results with a throughput closer to the speed of the line where speed of the line may be OC 192, i.e. a packet every 32 ns. It is based on a decision tree in which each node can be seen as a k-dimensional hypercube, in which each dimension of the hypercube is associated with a dimension in the rules of the classifier. In each node a decision is taken based on information from one or multiple fields. The fields chosen to be used in a decision process of a node are based on a set of heuristics that we develop. These heuristics take into account the overall memory that may be occupied by the whole search data structure as well as providing a maximal acceptable depth to the decision tree. The search structure also allows fast incremental updates, with an update time comparable with the time of the search. It can also be pipelined in which case the throughput may be increased to about one packet per 8 ns (limited by the speed of SRAM) in which case the packet classification operation may be applicable to OC 768 links.
ACL2 Workshop 2000 Proceedings, Part A, Lusk et al-Ruiz-Reina et al
Authors: Matt Kaufmann, J S Moore
Venue:  (2000)

The papers are listed in the order they were presented at the workshop. See http://www.cs.utexas.edu/users/moore/acl2/workshop-2000 for more information. Supporting scripts for many of the papers may be found at this site. This year we encouraged both long and short papers, the latter indended primarily to present work in progress.
Lower Bounds for Noisy Boolean Decision Trees
Authors: William Evans, Nicholas Pippernger
Venue:  (1996)

We present a new method for deriving lower bounds to the expected number of queries made by noisy decision trees computing Boolean functions. The new method has the feature that expectations are taken with respect to a uniformly distributed random input, as well as with respect to the random noise, thus yielding stronger lower bounds. It also applies to many more functions than do previous results. The method yields a simple proof of the result (previously established by Reischuk and Schmeltz) that almost all Boolean functions of n arguments require Omega(n log n) queries, and strengthens this bound from the worst-case over inputs to the average over inputs. The method also yields bounds for specific Boolean functions in terms of their spectra (their Fourier transforms). The simplest instance of this spectral bound yields the result (previously established by Feige, Peleg, Raghavan and Upfal) that the parity function of n arguments requires Omega(n log n) queries, and again strengthens this bound from the worst-case over inputs to the average over inputs. In its full generality, the spectral bound applies to the "highly resilient" functions introduced by Chor, Friedman, Goldreich, Hastad, Rudich and Smolensky, and it yields non-linear lower bounds whenever the resiliency is asymptotic to the number of arguments.
C++ CLASSES FOR THE EFFICIENT MANIPULATION AND STORAGE OF HIERARCHICAL OBJECTS
Authors: Dean R. E. Long
Venue:  (1993)

Many applications must efficiently store and manipulate complex objects. Often sub-objects or entire objects are identical. Memory use can be decreased by the use of object handles which point to shared objects in place of actual objects. If the objects are hierarchical, sub-objects can also be represented with handles, allowing many operations to manipulate handles instead of whole objects. The copy-on-write and object registration techniques presented here reduce the cost of storing, copying, modifying, and matching hierarchical objects. Using object registration, identical objects are detected and shared, allowing objects to be uniquely identified by their location in memory. Copy-on-write object semantics allows increased sharing and reduced copying, while hierarchical copy-on-write objects using handles allows copies to have deep-copy behavior but shallow-copy cost. 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
Scale-Based Descriptions of Planar Curves
Authors: Alan K. Mackworth, Farzin Mokhtarian
Venue:  (1984)

The problem posed in this paper is the description of planar curves at varying levels of detail. Five necessary conditiong are imposed on any candidate solution method. Two candidate methods are rejected. A new method that uses well-known Gaussian smoothing techniques but applies them in a path-based coordinate system is described. By smoothing with respect to a path-length parameter the difficulties of other methods are overcome. An example shows how the method extracts the major features of a curve, at varying levels of detail, based on segmentation at zeroes of the curvature, $\kappa$. The method satisfies the five necessary criteria.
Time-Parallel Simulation Using Partial State Matching for Queueing Systems
Authors: Jain J. Wang, Marc Abrams
Venue:  (1992)

This paper describes partial state matching for approximate time-parallel simulation. The notion of degree of freedom in time-parallel simulation is introduced. Two partial state matching algorithms are proposed to simulate acyclic networks of FCFS G/G/1/K queues in which arriving customers that find the queue full are lost. The algorithms are suitable for SIMD as well as MIMD architectures. The performance of the algorithms is studied. Experiment results with M/M/1/K and M/D/1/K queueing networks show that the potential speedup and simulation accuracy of the algorithms are good. The worst performance of both algorithms occurs when traffic intensity is one. Arguments are made to explain this phenomenon.
Implementation of Microcomputers in Elementary Schools: A Survey and Evaluation --- don''t reprint
Authors: Christine Chan
Venue:  (1986)

The objective of this thesis is to investigate the uses of computer aided learning (CAL) at the elementary level. Some recent publications on CAL are summarized and discussed. A questionnaire was used and interviews uere conducted with elementary teachers in four chosen school districts in Vancouver and Toronto. From this field research, information was collected on teachers'' perceptions on the use or CAL in the elementary classroom. This data is compared with observations presented in the relevant literature, and the comparison discussed within Robert Taylor''s framework or using the computer as tutor, tool, and tutee. Included are the results from the questionnaire. The thesis concludes with a discussion on the role of the teacher in the use or computers in the classroom, a flexible approach to adopting CAL, and possible areas for future research. 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
Efficient Parallel Algorithms for the Extraction of Image Features withadjustable Invariance Properties
Authors: Michael Nolle, Gerald Schreiber, Hanns Schulz-Mirbach
Venue:  (1995)

The paper presents algorithms for the extraction of image features which are invariant with respect to the action of a transformation group on the image data. We focus on the parallelization of these algorithms. The occuring data dependencies are typical for a whole class of algorithms. The resulting communication demands can be characterized by a set of parameters. According to the values of these parameters it is possible to find well suited topologies for the communication network. We analyze embeddings of these topologies into a fixed network structure and devise suitable data distributions.
Efficient support for pipelining in software distributed shared memory systems
Authors: Karthik Balasubramanian, David K. Lowenthal
Venue: Real-time system security (2003)

Though more difficult to program, distributed-memory parallel machines provide greater scalability than their shared-memory counterparts. Software Distributed Shared Memory (SDSM) systems provide the abstraction of shared memory on a distributed machine. While SDSMs provide an attractive programming model, they currently can not efficiently support all classes of scientific applications. One such class are those with recurrences that cause dependencies across processors or nodes. A popular solution to such problems is to use pipelining, which breaks the computation into blocks; each processor performs the computation of a block, which enables the next processor in the pipeline to compute its corresponding block. Once the pipeline is filled, the computation of blocks proceeds in parallel. While pipelining is useful, it is not efficiently supported by current SDSM systems.This paper presents an approach to integrating pipelining into SDSM systems. We describe our design and implementation of one-way pipelining in a SDSM. The key idea is to retain the shared-memory model, but design the extensions such that the execution will mimic what would be done in an explicit message-passing program. We show that one-way pipelining is superior to the two most common ways to program pipelined applications, which are distributed locks and explicit matrix transposition. Finally, we show that one-way pipelining is competitive with a hand-coded, explicit message-passing program.
The Design \& Control of Visual Routines for the Computation of Simple Geometric Properties \& Relations
Authors: Marc H. J. Romanycia
Venue:  (1987)

The present work is based on the Visual Routine theory of Shimon Ullman. This theory holds that efficient visual perception is managed by first applying spatially parallel methods to an initial input image in order to construct the basic representation-maps of features within the image. Then, this phase is followed by the application of serial methods --- visual routines --- which are applied to the most salient items in these and other subsequently created maps. Recent work in the visual routine tradition is reviewed, as well as relevant psychological work on preattentive and attentive vision. An analysis is made of the problem of devising a visual routine language for computing geometric properties and relations. The most useful basic representations to compute directly from a world of 2-D geometric shapes are determined. An argument is made for the case that an experimental program is required to establish which basic operations and which methods for controlling them will lead to the efficient computation of geometric properties and relations. A description is given of an implemented computer system which can correctly compute, in images of simple 2-D geometric shapes, the properties {\em vertical}, {\em horizontal}, {\em closed}, and {\em convex}, and the relations {\em inside}, {\em outside}, {\em touching}, {\em centred-in}, {\em connected}, {\em parallel}, and {\em being-part-of}. The visual routines which compute these, the basic operations out of which the visual routines are composed, and the important logic which controls the goal-directed application of the routines to the image are all described in detail. The entire system is embedded in a Question-and-Answer system which is capable of answering questions of an image, such as ``Find all the squares inside triangles'''' or ``Find all the vertical bars outside of closed convex shapes.'''' By asking many such questions about various test images, the effectiveness of the visual routines and their controlling logic is demonstrated.
How Fast Will The Flip Flop?
Authors: Mark R. Greenstreet, Peter Cahoon
Venue:  (1994)

This report describes an experimental investigation of the application of dynamical systems theory to the verification of digital VLSI circuits. We analyze the behavior of a nine-transistor toggle element using a simple, SPICE-like model. We show how such properties as minimum and maximum clock frequency can be identified from topological features of solutions to the corresponding system of differential equations. This dynamical systems perspective also gives a clear, continuous-model interpretations of such phenomena as dynamic storage and timing hazards.
The Ant Colony Optimization paradigm for combinatorial optimization
Authors: Antonella Carbonaro, Vittorio Maniezzo
Venue: Advances in evolutionary computing: theory and applications (2003)

Ant Colony Optimization is a paradigm for designing combinatorial optimization metaheuristic algorithms, which construct a solution on the basis of information provided both by some standard constructive heuristic and by previously obtained solutions. In this chapter, we present current results obtained by ACO algorithms on several hard combinatorial optimization problems. Furthermore, we describe in more detail a particular ACO algorithm, the ANTS metaheuristic, presenting its general structure and reporting results obtained on the quadratic and on the frequency assignment problems.
A Quantitative Assured Forwarding Service
Authors: Nicolas Christin, Jorg Liebeherr, Tarek F. Abdelzaher
Venue:  (2001)

The Assured Forwarding (AF) service of the IETF DiffServ architecture provides a qualitative service differentiation between classes of traffic, in the sense that a low-priority class experiences higher loss rates and higher delays than a high-priority class. However, the AF service does not quantify the difference in the service given to classes. In an effort to strengthen the service guarantees of the AF service, we propose a Quantitative Assured Forwarding service with absolute and proportional differentiation of loss, service rates, and packet delays. We present a feedback-based algorithm which enforces the desired class-level differentiation on a per-hop basis, without the need for admission control or signaling. Measurement results from a testbed of FreeBSD PC-routers on a 100 Mbps Ethernet network show the effectiveness of the proposed service, and indicate that our implementation is suitable for networks with high data rates.
REGULARIZERS FOR ESTIMATING DISTRIBUTIONS OF AMINO ACIDS FROM SMALL SAMPLES
Authors: Kevin Karplus
Venue:  (1995)

This paper examines several different methods for estimating the distribution of amino acids in a specific context, given a very small sample of amino acids from that distribution. These distribution estimators, sometimes called regularizers, are frequently used when aligning sequences to each other or to models such as profiles or hidden Markov models. The distribution estimators considered here are zero-offsets, pseudocounts, substitution matrices (with several variants), feature alphabets, and Dirichlet mixture regularizers. A new method is presented for setting the parameters of the regularizers to minimize the encoding cost (also called the entropy) of the training data, for all possible samples from the training data. The optimal parameter settings depend on the size of the sample, but the optimization method can also be used to get good performance over a range of sample sizes. The optimal settings with this method are not the same as the traditional values used for the parameters. The regularizers are evaluated based on how well they estimate the distributions of the columns of a multiple alignment---specifically, the expected encoding cost per amino acid using the regularizer method and all possible samples from each column. The differences between the regularizers are fairly small (less than 0.2 bits per column), but large enough to make a significant difference when many columns are combined as is done in an an alignment. In general, the pseudocounts have the lowest encoding costs for samples of size zero, substitution matrices have the lowest encoding costs for samples of size one, and Dirichlet mixtures have the lowest for larger samples. One of the substitution matrix variants, which added pseudocounts and scaled counts, does almost as well as the best Dirichlet mixtures, but with a lower computation cost.