ppxscal/embedding_network huggingface dataset:
Performance Evaluation in Computational Grid Environments
Authors: Liang Peng, Simon See, Yueqin Jiang, Jie Song, Appie Stoelwinder, Hoon Kang Neo
Venue: Proceedings of the High Performance Computing and Grid in Asia Pacific Region, Seventh International Conference (2004)

Grid computing has been developed extensive in recently years and is becoming an important platform for high performance computing in scientific areas. Grid performance evaluation is an important approach to improve the performance of Grid systems and applications. However, few work has been conducted in grid performance evaluation due to a lot of reasons like lack of appropriate grid performance metrics, complexity of the grids, etc. In this paper, we analyze the performance metrics like response time and system utilization in the computational grid environment. We argue that instead of calculating the system utilization in the traditional, a concept of relative grid utilization, which describes how close is a single grid application performance to the performance of the same application submitted without grid middleware. We also discuss the utilization for the grid systems processing a number of jobs. In our experiments, we use NPB/NGB to evaluate the APSTC cluster grid and NTU Campus Grid performance, especially the overhead of SGE and Globus. Our results show that the overhead of grid middleware turns to be ignorable when the job size grows, and the characteristics of the grid applications affect a lot on utilization of computational grids.
Large Cells in Poisson&#x2013;Delaunay Tessellations
Authors: Daniel Hug, Rolf Schneider
Venue: Discrete Computational Geometry (2004)

It is proved that the shape of the typical cell of a Delaunay tessellation, derived from a stationary Poisson point process in d-dimensional Euclidean space, tends to the shape of a regular simplex, given that the volume of the typical cell tends to infinity. This follows from an estimate for the probability that the typical cell deviates by a given amount from regularity, given that its volume is large. As a tool for the proof, a stability result for simplices is established.
Efficient scalable VLSI architecture for Montgomery inversion in GF(p)
Authors: Adnan Abdul-Aziz Gutub, Alexandre Ferreira Tenca
Venue: Integration, the VLSI Journal (2004)

The multiplicative inversion operation is a fundamental computation in several cryptographic applications. In this work, we propose a scalable VLSI hardware to compute the Montgomery modular inverse in GF(p). We suggest a new correction phase for a previously proposed almost Montgomery inverse algorithm to calculate the inversion in hardware. We also propose an efficient hardware algorithm to compute the inverse by multi-bit shifting method. The intended VLSI hardware is scalable, which means that a fixed-area module can handle operands of any size. The word-size, which the module operates, can be selected based on the area and performance requirements. The upper limit on the operand precision is dictated only by the available memory to store the operands and internal results. The scalable module is in principle capable of performing infinite-precision Montgomery inverse computation of an integer, modulo, a prime number. This scalable hardware is compared with a previously proposed fixed (fully parallel) design showing very attractive results.
Enhancing classroom lectures with digital sliding blackboards
Authors: Guido Röüling, Christoph Trompler, Max Mühlhäuser, Susanne Köbler, Susanne Wolf
Venue: Proceedings of the 9th annual SIGCSE conference on Innovation and technology in computer science education (2004)

Traditional blackboard-based lectures provide context on the sliding blackboards. Modern lectures incorporating video projectors typically do not provide this context. We describe a project that combines both approaches to provide context for "modern'' lectures. We also discuss the benefits for educators and students. The software is sufficiently versatile to incorporate practically any software for content display.
Customisation and Context for Expressive Behaviour in the Broadband World
Authors: M. Gillies
Venue: BT Technology Journal (2004)

The introduction of consumer broadband makes it possible to have an emotionally much richer experience of the Internet. One way of achieving this is the use of animated characters endowed with emotionally expressive behaviour. This paper describes Demeanour, a framework for generating expressive behaviour, developed collaboratively by University College London and BT. The focus of this paper will be on two important aspects &mdash; the customisation of expressive behaviour and how expressive behaviour can be made context dependent.
A novel analytical framework compounding statistical traffic modeling and aggregate-level service curve disciplines: network performance and efficiency implications
Authors: Alfio Lombardo, Giacomo Morabito, Giovanni Schembra
Venue: IEEE/ACM Transactions on Networking (TON) (2004)

This paper demonstrates that higher network resource efficiency can be achieved by using resource management protocols which consider service disciplines based on service curves together with statistical traffic modeling. To this end, an appropriate analytical framework is introduced which allows calculation of the performance statistically guaranteed to any flow out of an aggregate. This feature enables the analytical framework to be applied to the elements of the core network where aggregates of traffic are considered instead of single flows in order to avoid scalability problems. Given that flows are modeled in the analytical framework through switched batch Bernoulli processes (SBBPs), the whole queueing system is denoted as SBBP/Sc/1/K. The performance is calculated in terms of loss probability and delay distribution. The proposed framework is applied in a significant multinode case study.
A k-Median Algorithm with Running Time Independent of Data Size
Authors: Adam Meyerson, Liadan O'Callaghan, Serge Plotkin
Venue: Machine Learning (2004)

We give a sampling-based algorithm for the k-Median problem, with running time O(k(\frac{k^2}{\epsilon} log k)2 log(\frac{k}{\epsilon} log k)), where k is the desired number of clusters and &epsi; is a confidence parameter. This is the first k-Median algorithm with fully polynomial running time that is independent of n, the size of the data set. It gives a solution that is, with high probability, an O(1)-approximation, if each cluster in some optimal solution has &Omega;(\frac{n\epsilon}{k}) points. We also give weakly-polynomial-time algorithms for this problem and a relaxed version of k-Median in which a small fraction of outliers can be excluded. We give near-matching lower bounds showing that this assumption about cluster size is necessary. We also present a related algorithm for finding a clustering that excludes a small number of outliers.
Session-Based Quality of Service
Authors: S. Rudkin
Venue: BT Technology Journal (2004)

A primary objective of a next generation network architecture is to develop a set of infrastructure capabilities that facilitate the creation and delivery of premium services. One of these capabilities, session-based quality of service (QoS), may be used by service providers or application service providers to assure the quality of delivery of their IP content/application sessions over broadband networks.This paper introduces session-based QoS and discusses a number of considerations arising in the design of this capability for broadband services in the next few years.
Development Works for Integrated-Study with Co-operations of Community
Authors: Noriko Morita, Kohei Yamamoto, Takeshi Nakatani, Masaki Shirai, Masami Ichihashi
Venue: Proceedings of the Second International Conference on Creating, Connecting and Collaborating through Computing (2004)

We reached a consensus that the main factorbehind the current decline in community power mightbe the rapid deterioration in the volume and quality ofcommunication within the community, as it sees itscommon conventions and goals being lost. Ourresearch revealed that "children, women and theaged", while thought generally to be the key players incommunity revitalization, were also unfortunatelyperceived as being on the isolated side of the digitaldivide. Based on these premises, we set a commongoal for the internal community as a whole, i.e., "toinculcate children with a sense of the community'sresponsibility". By assisting in the development ofeducational programs with which it was involved, thisbegan to lead to the establishment of commonagreement. For the following period of around a year,during the "Periods for Integrated Study" at amunicipal elementary school, we implemented "thedevelopment of curricula and environments to enhancechild creativity and problem-solving skills withoutrequiring special personal or financial resources"through the use of IT.
Weakening conflicting information for iterated revision and knowledge integration
Authors: Salem Benferhat, Souhila Kaci, Daniel Le Berre, Mary-Anne Williams
Venue: Artificial Intelligence (2004)

The ability to handle exceptions, to perform iterated belief revision and to integrate information from multiple sources is essential for a commonsense reasoning agent. These important skills are related in the sense that they all rely on resolving inconsistent information. In this paper we develop a novel and useful strategy for conflict resolution, and compare and contrast it with existing strategies. Ideally the process of conflict resolution should conform with the principle of Minimal Change and should result in the minimal loss of information. Our approach to minimizing the loss of information is to weaken information involved in conflicts rather than completely discarding it. We implemented and tested the relative performance of our new strategy in three different ways. Surprisingly, we are able to demonstrate that it provides a computationally effective compilation of the lexicographical strategy; a strategy which is known to have desirable theoretical properties.
Cluster-Based Failure Detection Service for Large-Scale Ad Hoc Wireless Network Applications
Authors: Ann T. Tai, Kam S. Tso, William H. Sanders
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

The growing interest in ad hoc wireless network applicationsthat are made of large and dense populations oflightweight system resources calls for scalable approachesto fault tolerance. Moreover, the nature of these systemscreates significant challenges for the development of failuredetection services (FDSs), because their quality often dependsheavily on reliable communication. In particular, adhoc wireless networks are notoriously vulnerable to messageloss, which precludes deterministic guarantees for thecompleteness and accuracy properties of FDSs. To meetthe challenges, we propose an FDS based on the notion ofclustering. Specifically, we use a cluster-based communicationarchitecture to permit the FDS to be implementedin a distributed manner via intra-cluster heartbeat diffusionand to allow a failure report to be forwarded across clustersthrough the upper layer of the communication hierarchy.In doing so, we extensively exploit the message redundancythat is inherent in ad hoc wireless settings to mitigate theeffects of message loss on the accuracy and completenessproperties of failure detection. As shown by our mathematicalanalysis, the resulting FDS is able to provide satisfactoryprobabilistic guarantees for the desired properties.
Tolerating Hard Faults in Microprocessor Array Structures
Authors: Fred A. Bower, Paul G. Shealy, Sule Ozev, Daniel J. Sorin
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

In this paper, we present a hardware technique, calledSelf-Repairing Array Structures (SRAS), for maskinghard faults in microprocessor array structures, such asthe reorder buffer and branch history table. SRAS maskserrors that could otherwise lead to slow system recoveries.To detect row errors, every write to a row is mirroredto a dedicated "check row." We then read out boththe written row and check row and compare theirresults. To correct errors, SRAS maps out faulty arrayrows with a level of indirection.
The Extreme Points of Subsets of s-Concave Probabilities and a Geometric Localization Theorem
Authors: Matthieu Fradelizi, Olivier Gu&#x00e9;don
Venue: Discrete Computational Geometry (2004)

We prove that the extreme points of the set of s-concave probability measures satisfying a linear constraint are some Dirac measures and some s-affine probabilities supported by a segment. From this we deduce that the constrained maximization of a convex functional on the s-concave probability measures is reduced to this small set of extreme points. This gives a new approach to a localization theorem due to Kannan, Lov&#x00e1;sz and Simonovits which happens to be very useful in geometry to obtain inequalities for integrals like concentration and isoperimetric inequalities. Roughly speaking, the study of such inequalities is reduced to these extreme points.
Cuts, Trees and &#x2113;1-Embeddings of Graphs*
Authors: Anupam Gupta, Ilan Newman, Yuri Rabinovich, Alistair Sinclair
Venue: Combinatorica (2004)

Motivated by many recent algorithmic applications, this paper aims to promote a systematic study of the relationship between the topology of a graph and the metric distortion incurred when the graph is embedded into &#x2113;1 space. The main results are:1. Explicit constant-distortion embeddings of all series-parallel graphs, and all graphs with bounded Euler number. These are the first natural families known to have constant distortion (strictly greater than 1). Using the above embeddings, algorithms are obtained which approximate the sparsest cut in such graphs to within a constant factor.2. A constant-distortion embedding of outerplanar graphs into the restricted class of &#x2113;1-metrics known as &#x201c;dominating tree metrics&#x201d;. A lower bound of &#x03a9;(log n) on the distortion for embeddings of series-parallel graphs into (distributions over) dominating tree metrics is also presented. This shows, surprisingly, that such metrics approximate distances very poorly even for families of graphs with low treewidth, and excludes the possibility of using them to explore the finer structure of &#x2113;1-embeddability.
Super wide viewer using catadioptrical optics
Authors: Hajime Nagahara, Yasushi Yagi, Masahiko Yachida
Venue: Proceedings of the ACM symposium on Virtual reality software and technology (2003)

Many applications have used a Head-Mounted Display (HMD), such as in virtual and mixed realities, and tele-presence. The advantage of HMD systems is the ease of feeling a 3D world in the display of animation or movies. However, the field of view (FOV) of commercial HMD systems is too narrow for feeling immersion. The horizontal FOV of many commercial HMDs is around 60 degrees, significantly narrower than that of humans. In this paper, we propose a super wide field of view head-mounted display consisting of an ellipsoidal and a hyperboloidal curved mirror. The horizontal FOV of the proposed HMD is 180 degrees and includes the peripheral view of humans. It increases reality and immersion of users. As well, the central region (60 degrees) of the FOV can measure 3D distances using stereoscopics.
Convergence conundrums
Authors: Dennis Fowler
Venue: netWorker (2002)

"Convergence" is one of those buzz-words that refuses to die. And why should it? On the face of it, the coalescing of computers and networks and communications and electronic and electrical appliances is, well "doh," as Homer Simpson might say.
Content-based Image Retrieval Using Approximate Shape of Objects
Authors: Agma J. M. Traina, Andre G. R. Balan, Luis M. Bortolotti, Caetano Traina Jr.
Venue: Proceedings of the 17th IEEE Symposium on Computer-Based Medical Systems (2004)

This paper presents a new approach to retrieve images by content using a composition of relevant features regarding texture, shape and brightness distribution. The first step of the method is a segmentation process based on Markov Random Fields, which can be done automatically, having as parameter the number of desired classes. The regions obtained in the segmentation guide the extraction of measures from the original image producing a 30-dimensional feature vector used in the image retrieval. The experiments showed that the feature vector has high discrimination power and the time for retrieval operations are only fractions of seconds.
Implementation of a Storage Mechanism for Untrusted DBMSs
Venue: Proceedings of the Second IEEE International Security in Storage Workshop (2003)

Several architectures have been recently proposed thatstore relational data in encrypted form on untrusted relationaldatabases. Such architectures permit the creation ofnovel Internet services and also offer an opportunity for abetter construction of ASP solutions. Environments wherethere are limited resources that do not permit an efficientmanagement of databases or where it is critical to offer arobust Internet access to private data may all benefit fromthe above architectures. In this paper we analyze the impactthat this architecture has on the typical services of adatabase. The analysis is based on the experience gainedin the construction of a prototype of a complete architecturefor the management of encrypted databases. Specifically,we illustrate the impact on query translation and optimization,and the main components of the software architectureof the prototype.
Binary Space Partitions for Axis-Parallel Segments, Rectangles, and Hyperrectangles
Authors: Adrian Dumitrescu, Joseph S. B. Mitchell, Micha Sharir
Venue: Discrete Computational Geometry (2004)

We provide a variety of new upper and lower bounds and simpler proof techniques for the efficient construction of binary space partitions (BSPs) of axis-parallel rectangles of various dimensions. (a) We construct a set of $n$ disjoint axis-parallel segments in the plane such that any binary space auto-partition has size at least $2n-o(n)$, almost matching an upper bound of d&#x2019;Amore and Franciosa. (b) We establish a similar lower bound of $7n/3-o(n)$ for disjoint rectangles in the plane. (c) We simplify and improve BSP constructions of Paterson and Yao for disjoint segments in $\reals^d$ and disjoint rectangles in $\reals^3$. (d) We derive a worst-case bound of $\Theta(n^{5/3})$ for the size of BSPs of disjoint $2$-rectangles in $4$-space. (e) For disjoint $k$-rectangles in $d$-space, we prove the worst-case bound $\Theta(n^{d/(d-k)})$, for any $k<d/2$; this bound holds for all $k<d$ if the rectangles are allowed to intersect.
In Advance Activation of Backup Channels for Real-Time Transmission
Authors: Enrique Hernandez Orallo, Joan Vila Carbo
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

Real-time transmission implies guaranteeing a givenQuality of Service (QoS), requiring large use of networkresources. Backup Channels introduce the notion ofavailability to real-time transmission at the cost ofincreasing the use of network resources. However, thisover-provisioning of resources is potentially wasted, sincefault rate is very low. This paper introduces a new failuredetection scheme for Real-time Transmission calledProactive Backup Channel. This scheme is based onactivating the backup channel before a fail is produced.As proven in the paper, this scheme reduces the use ofnetwork resources and is suitable for Integrated andDifferentiated services.
Deterministic Polynomial Identity Testing in Non-Commutative Models
Authors: Ran Raz, Amir Shpilka
Venue: Proceedings of the 19th IEEE Annual Conference on Computational Complexity (2004)

We give a deterministic polynomial time algorithm forpolynomial identity testing in the following two cases:1. Non Commutative Arithmetic Formulas: The algorithmgets as an input an arithmetic formula in thenon-commuting variables x1, ..., xn and determineswhether or not the output of the formula is identically0 (as a formal expression).2. Pure Arithmetic Circuits: The algorithm gets as aninput a pure arithmetic circuit (as defined by Nisanand Wigderson [3]) in the variables x1, ..., xn and determineswhether or not the output of the circuitidentically 0 (as a formal expression).We also give a deterministic polynomial time identity testingalgorithm for non commutative algebraic branching programsas defined by Nisan [2]. One application is a deterministicpolynomial time identity testing for multilineararithmetic circuits of depth 3.Finally, we observe an exponential lower bound for thesize of pure arithmetic circuits for the permanent and for thedeterminant. (Only lower bounds for the depth of pure circuitswere previously known [3]).
Using eternity variables to specify and prove a serializable database interface
Authors: Wim H. Hesselink
Venue: Science of Computer Programming (2004)

Eternity variables are introduced to specify and verify serializability of transactions of a distributed database. Eternity variables are a new kind of auxiliary variables. They do not occur in the implementation but are used in specification and verification. Elsewhere it has been proved that eternity variables in combination with history variables are semantically complete for proving refinement relations.An eternity variable can be thought of as an unknown constant that is determined by the behaviour (execution sequence). In the specification of the database, one eternity variable is used to enforce serialization. In the verification, an additional eternity variable is needed for the connection of the local data with the shared database.The formalism is based on linear-time temporal logic, but the analysis of behaviours is completely reduced to the next-state relation together with progress arguments using variant functions. Forward invariants (inductive predicates) are complemented with other, so-called backward, invariants. The proof has been verified with the first-order theorem prover NQTHM to give additional confidence in the result and in the feasibility of the approach.
SaIL: A Library for Efficient Application Integration of Spatial Indices
Authors: Marios Hadjieleftheriou, Erik G. Hoel, Vassilis J. Tsotras
Venue: Proceedings of the 16th International Conference on Scientific and Statistical Database Management (2004)

Many scientific applications deal with spatial, spatiotemporaland other multidimensional indexing structures, typicallymanaging millions of objects with arbitrary and complexfeatures. Choosing the appropriate method to indexsuch data becomes rather difficult. Having an index librarythat can combine different indices under the same programminginterface is thus very valuable. In this paper we presentSaIL (SpAtial Index Library), a robust and extensible librarythat enables simple integration of spatial index structures inexisting applications. We mainly focus on design issues andelaborate on techniques for making the framework genericenough, so that it can support user defined data types, customizablespatial queries, and a broad range of spatial (andspatio-temporal) index structures. The library is publiclyavailable and has already been successfully utilized for researchand commercial applications.