ppxscal/embedding_network huggingface dataset:
Properties of two&#x2019;s complement floating point notations
Authors: Sylvie Boldo, Marc Daumas
Venue: International Journal on Software Tools for Technology Transfer (STTT) (2004)

Few designs, mostly those of Texas Instruments, continue to use two&#x2019;s complement floating point units. Such units are simpler to build and to validate, but they do not comply to the dominant IEEE standard for floating point arithmetic. We compare some properties of the two systems in this text. Some features are lost, but others remain unchanged. One strong example is the case of Sterbenz&#x2019;s theorem and our recent extension. We show in the paper that the theorem and its extension hold for the two&#x2019;s complement architecture. Still, users should ensure that results are large enough on circuits that do not implement gradual underflow. Theorems have been proven and validated using the Coq automatic proof checker.
Teaching OOP: experimental studies
Authors: Richard Borge
Venue: ACM SIGCSE Bulletin (2004)

Last year, an experiment was conducted on six novice students, attempting to teach them OOP (Object Oriented Programming) in 2.5 days using Karel J. The students learnt making their own subclasses with methods after 8 hours. A follow-up experiment will be attempted, spanning over more days using children in elementary school.
Iterative Abstraction using SAT-based BMC with Proof Analysis
Authors: Aarti Gupta, Malay Ganai, Zijiang Yang, Pranav Ashar
Venue: Proceedings of the 2003 IEEE/ACM international conference on Computer-aided design (2003)

Resolution-based proof analysis techniques have been proposedrecently to identify a sufficient set of reasons for unsatisfiabilityderived by a CNF-based SAT solver. We have adapted thesetechniques to work with a hybrid SAT solver. We use the proofanalysis technique with SAT-based BMC, in order to generateuseful abstract models. Our abstraction procedure is usediteratively in a top-down framework, starting from the concretedesign, where we apply BMC on increasingly more abstractmodels. We apply various SAT-based and BDD-basedverification methods on these abstract models, in order to obtainproofs of correctness, or to perform deeper searches forcounterexamples. We demonstrate the effectiveness of ourprototype implementation on several large industry designs.
Shannon Information in Complete Genomes
Authors: Chang-Heng Chang, Li-Ching Hsieh, Ta-Yuan Chen, Hong-Da Chen, Liaofu Luo, Hoong-Chien Lee
Venue: Proceedings of the 2004 IEEE Computational Systems Bioinformatics Conference (2004)

Shannon information in the genomes of all completely sequenced prokaryotes and eukaryotes are measured in word lengths of two to ten letters. It is found that in a scale-dependent way, the Shannon information in complete genomes are much greater than that in matching random sequences - thousands of times greater in the case of short words. Furthermore, with the exception of the 14 chromosomes of Plasmodium falciparum, the Shannon information in all available complete genomes belong to a universality class given by an extremely simple formula. The data are consistent with a model for genome growth composed of two main ingredients: random segmental duplications that increase the Shannon information in a scale-independent way, and random point mutations that preferentially reduces the larger-scale Shannon information. The inference drawn from the present study is that the large-scale and coarse-grained growth of genomes was selectively neutral and this suggests an independent corroboration of Kimuraýs neutral theory of evolution.
A Markov Reward Model for Reliable Synchronous Dataflow System Design
Authors: Vinu Vijay Kumar, Rashi Verma, John Lach, Joanne Bechta Dugan
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

The design of quality digital systems depends on modelsthat accurately evaluate various options in the designspace against a set of prioritized metrics. Whileindividual models for evaluating area, performance,reliability, power, etc. are well established, modelscombining multiple metrics are less mature. This paperintroduces a formal methodology for comprehensivelyanalyzing performance, area and reliability in the designof synchronous dataflow systems using a novel MarkovReward Model. A Markov chain system reliability modelis constructed for various design options in the presenceof possible component failures, and high-level synthesistechniques are used to associate performance and arearewards with each state in the chain. The cumulativereward for a chain is then used to evaluate thecorresponding design option with respect to the metricsof interest. Application of the model to a benchmark DSPcircuit provides insights into reliable synchronousdataflow system design.
Skeleton " Easy Simulation System
Authors: Takashi Yamamiya
Venue: Proceedings of the Second International Conference on Creating, Connecting and Collaborating through Computing (2004)

Skeleton is a visual scripting environment as anextension of Squeak etoy [1] with Connectors [2] systemto make mathematical and physical simulation for nonprofessional computer user. Squeak etoy system is aunique attempt to provide effective way of programmingfor children in learning environment. Skeleton makeslogical relationships among graphical objects in the etoysystem with spreadsheets-style interface, and users candescribe objectýs behavior in declarative representation.Concreteness is one of the key words of end userscripting. Direct manipulation with objects on the screen ishelpful to understand what is happened in your computer.Skeletonýs spreadsheets style interface realizes thisconcreteness to show any input and output data same time.Sometime user scripting system like etoy has aproblem of modularity. This aspect is important as a basisof reusing, thus Skeleton has some features for reusing.Tree structured naming system like ECMAScipt [3] is usedto access to Skeleton object by name. And modularity isrealized by sheet-card mechanism that is possible to reusea behavior of objects in another context in Skeleton.
Stable, high-order discretization for evolution of the wave equation in 1 + 1 dimensions
Authors: John Visher, Stephen Wandzura, Amanda White
Venue: Journal of Computational Physics (2004)

We carry forward the approach of Alpert, Greengard, and Hagstrom to construct stable high-order explicit discretizations for the wave equation in one space and one time dimension. They presented their scheme as an integral form of the Lax-Wendroff method. Our perspective is somewhat different from theirs; our focus is on the discretization of the evolution formula rather than on its form (integral, differential, etc.). A key feature of our approach is the independent computation of three discretizations, one for bulk (away from boundaries) propagation, one for propagation near boundaries, and a projection operator to enforce boundary conditions. This is done in a way that is straightforward to extend to more space dimensions.
Sumsets Containing Powers of an Integer
Authors: Tetsuya Abe
Venue: Combinatorica (2004)

Let n&#x2265;1, and let m be an integer with m&#x2265;2. We show that if a subset A of the interval [0,n] satisfies that 0&#x2208;A and |A|>1+n/2, then mA, the set of the sum of m (not necessarily distinct) elements in A, has a power of m. This result is best possible in the case that m is odd.
The Recursive NanoBox Processor Grid: A Reliable System Architecture for Unreliable Nanotechnology Devices
Authors: A. J. KleinOsowski, Kevin KleinOsowski, Vijay Rangarajan, Priyadarshini Ranganath, David J. Lilja
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

Advanced molecular nanotechnology devices are expectedto have exceedingly high transient fault rates and largenumbers of inherent device defects compared to conventionalCMOS devices. We introduce the Recursive NanoBoxProcessor Grid as an application specific, fault-tolerant,parallel computing system designed for fabrication with unreliablenanotechnology devices. In this initial study weconstruct VHDL models of the NanoBox Processor cellALU and evaluate the effectiveness of our recursive faultmasking approach in the presence of random transient errors.Our analysis shows that the ALU can calculate correctly100 percent of the time with raw FIT (failures in time)rates as high as 10{23}. We achieve this error correction withan area overhead on the order of 9x, which is quite reasonablegiven the high integration densities expected with nanodevices.
A New Interpolation Free Method for X-ray CT Image Reconstruction
Authors: Abhishek Mitra, Swapna Banerjee
Venue: Proceedings of the 17th IEEE Symposium on Computer-Based Medical Systems (2004)

The New Fast Radon Transform (NFRT) algorithm proposed by the authors is applied here toreconstruct the X-ray CT image. Satisfactory agreement between the original andreconstructed images was obtained. The algorithm does not require computation intensivedata interpolation and convert directly between a raster scan grid and the rectangular/polargrid in one step as compared to the back-projection method. Most importantly the compatibility of this algorithm for the X-ray CT system is also verified here.
From Surface to Intensive Matching of Semantic Web Ontologies
Authors: S. Castano, A. Ferrara, S. Montanelli, G. Racca
Venue: Proceedings of the Database and Expert Systems Applications, 15th International Workshop (2004)

In this paper, we describe the application of the H-MATCH algorithm to OWL Semantic Web ontology matching. H-MATCH dynamically performs ontology matching at different levels of depth, with different degrees of flexibility and accuracy. Some experimental results are reported.
PM/InfiniBand-FJ: A High Performance Communication Facility Using InfiniBand for Large Scale PC Clusters
Authors: Shinji Sumimoto, Akira Naruse, Kouichi Kumon, Kouji Hosoe, Toshiyuki Shimizu
Venue: Proceedings of the High Performance Computing and Grid in Asia Pacific Region, Seventh International Conference (2004)

This paper describes a design of high performance communication facility called the PM/InfiniBand-FJ using InfiniBand interconnect for large scale PC clusters. The PM/InfiniBand-FJ has developed to realize higher application performance than commercial supercomputers and comparable availability to them. Since the specification of InfiniBand interconnect is designed for communication among servers and I/Os, there are some issues to use InfiniBand for high performance computation on over 1000 node PC clusters. Therefore, the PM/InfiniBand-FJ solves the issues by expanding the original specification of InfiniBand. We have implemented the PM/InfiniBand-FJ on SCore cluster system software, and evaluated the communication and application performance. The performance results show that a 913.2 MB/s of bandwidth and 15.6 ¿s round trip time have been achieved on Xeon 2.8GHz PC with ServerWorks GC LE chipset. The result of NAS parallel benchmark shows that the 128 node result of IS Class B on PM/InfiniBand-FJ is 1.52 times faster than that of PM/MyrinetXP using Fujitsu PRIMERGY RX200 PC cluster (Xeon 3.06GHz).
A posteriori error analysis for elliptic pdes on domains with complicated structures
Authors: Carsten Carstensen, Stefan A. Sauter
Venue: Numerische Mathematik (2004)

The discretisation of boundary value problems on complicated domains cannot resolve all geometric details such as small holes or pores. The model problem of this paper consists of a triangulated polygonal domain with holes of a size of the mesh-width at most and mixed boundary conditions for the Poisson equation. Reliable and efficient a posteriori error estimates are presented for a fully numerical discretisation with conforming piecewise affine finite elements. Emphasis is on technical difficulties with the numerical approximation of the domain and their influence on the constants in the reliability and efficiency estimates.
A Formal Foundation for XrML
Authors: Joseph Y. Halpern, Vicky Weissman
Venue: Proceedings of the 17th IEEE workshop on Computer Security Foundations (2004)

XrML is becoming a popular language in industry forwriting software licenses. The semantics for XrML is implicitlygiven by an algorithm that determines if a permissionfollows from a set of licenses. We focus on a representativefragment of the language and use it to highlightsome problematic aspects of the algorithm. We then correctthe problems, introduce formal semantics, and showthat our semantics matches the (corrected) algorithm. Finally,we consider the complexity of determining if a permissionis implied by a set of XrML licenses. We show thatthe general problem is NP-hard, but it is polynomial-timecomputable for an expressive fragment of the language.
A compressed accessibility map for XML
Authors: Ting Yu, Divesh Srivastava, Laks V. S. Lakshmanan, H. V. Jagadish
Venue: ACM Transactions on Database Systems (TODS) (2004)

XML is the undisputed standard for data representation and exchange. As companies transact business over the Internet, letting authorized customers directly access, and even modify, XML data offers many advantages in terms of cost, accuracy, and timeliness. Given the complex business relationships between companies, and the sensitive nature of information, access must be provided selectively, using sophisticated access control specifications. Using the specification directly to determine if a user has access to an XML data item can be extremely inefficient. The alternative of fully materializing, for each data item, the users authorized to access it can be space-inefficient. In this article, we introduce a compressed accessibility map (CAM) as a space- and time-efficient solution to the access control problem for XML data. A CAM compactly identifies the XML data items to which a user has access, by exploiting structural locality of accessibility in tree-structured data. We present a CAM lookup algorithm for determining if a user has access to a data item that takes time proportional to the product of the depth of the item in the XML data and logarithm of the CAM size. We develop an algorithm for building an optimal size CAM that takes time linear in the size of the XML data set. While optimality cannot be preserved incrementally under data item updates, we provide an algorithm for incrementally maintaining near-optimality. Finally, we experimentally demonstrate the effectiveness of the CAM for multiple users on a variety of real and synthetic data sets.
Synthesising Facial Emotions
Venue: Proceedings of the Theory and Practice of Computer Graphics 2004 (TPCG'04) (2004)

We present two approaches for the generation of novelvideo textures which portray a human expressing differentemotions. Here training data is provided by video sequencesof an actress expressing specific emotions such asangry, happy and sad. The main challenge of modellingthese video texture sequences is the high variance in headposition and facial expression. Principal Components Analysis(PCA) is used to generate so called ýmotion signaturesýwhich are shown to be complex and have non-Gaussian distributions.The first method uses a combined appearancemodel to transform the video data into a lower dimensionalGaussian space. This can then be modelled using a standardautoregressive process. The second technique presented extractssub-samples from the original data using short temporalwindows, some of which have Gaussian distributionsand can be modelled by an autoregressive process (ARP).We find that the combined appearance technique producesmore aesthetically pleasing clips but does not maintain themotion characteristics as well as the temporal window approach.
Autonomic 802.11 Wireless LAN Security Auditing
Authors: Joel W. Branch, Nick L. Petroni Jr., Leendert Van Doorn, David Safford
Venue: IEEE Security and Privacy (2004)

The authors describe their Distributed Wireless Security Auditor (DWSA), which works toward finding unauthorized wireless access points in large-scale wireless environments while providing an autonomic and unobtrusive layer of network protection.
A Survey of Secure Wireless Ad Hoc Routing
Authors: Yih-Chun Hu, Adrian Perrig
Venue: IEEE Security and Privacy (2004)

Ad hoc networks use mobile nodes to enable communication outside wireless transmission range. Attacks on ad hoc network routing protocols disrupt network performance and reliability. The authors survey the state of research and its challenges in this field.
Flexible tooling for localized electrochemical deposition with wire-electrodischarge grinding
Authors: J. H. Choo, S. H. Yeo, F. F. Tan
Venue: Microsystem Technologies (2004)

This paper describes the application of electrodes with varying diameters made by wire-electrodischarge grinding (WEDG) in the localized electrochemical deposition (LECD) of nickel micro-columns. WEDG has been widely used in the fabrication of extremely fine cylindrical pins mainly used as tool electrodes for micro-electrodischarge machining of fine holes or as contoured cores in the electroforming of micropipes. Similar to electrolysis, LECD is a new deposition technique which uses conductive tips as anode electrodes to focus the electric field that drives the process such that deposition is largely localized on the smooth cathode surface beneath the anode tip. The degree of localization depends mainly on the anode diameter, the anode-to-cathode separation, the insulation or non-insulation of the anode, and the computer-controlled motion of the anode tip during the deposition process. Considering the parameter of anode tip diameter alone, the ability to fabricate tips of differing diameters will allow a wide range in resolution of structures deposited via LECD. WEDG provides this flexible tooling for LECD at the micro to meso-scale. Experiments were carried out on a custom-built LECD rig on which nickel columns were deposited from a nickel sulphamate plating solution, using stationary and rotating WEDG-ed tips with diameters ranging from 25 to 120 &#x03bc;m. Aspect ratios of up to 9:1 were achieved and deposited column diameters were found to display a linear relationship with the WEDG-ed anode tip diameters. Electrode rotation was also found to improve column cross-sectional roundness and overall dimensional control for fabrication with LECD.
Dominant parameter selection in the marginally identifiable case
Authors: Ilya Ioslovich, Per-Olof Gutman, Ido Seginer
Venue: Mathematics and Computers in Simulation (2004)

Often a rather limited set of experimental data is available for the identification of a dynamic model, which contains many parameters. This is, e.g. the usual case for crop growth models. In this situation, only some parameter values can be estimated. Based on an analysis of the Fisher information matrix, a method for a reasonable selection of parameters is suggested here. The method chooses the most sensitive parameters, i.e. those to which the model under the considered experimental conditions is most sensitive, and excludes both coupled parameters and those that exhibit multiplecorrelation. A comparison with different ridge regression methods is made. The methodology is illustrated with a simple lettuce growth model.
An Effectiveness Measure for Software Clustering Algorithms
Venue: Proceedings of the 12th IEEE International Workshop on Program Comprehension (2004)

Selecting an appropriate software clustering algorithmthat can help the process of understanding a large softwaresystem is a challenging issue. The effectiveness of a particularalgorithm may be influenced by a number of differentfactors, such as the types of decompositions produced, orthe way clusters are named.In this paper, we introduce an effectiveness measure forsoftware clustering algorithms based on MoJo distance,and describe an algorithm that calculates its value. We alsopresent experiments that demonstrate its improved performanceover previous measures, and show how it can be usedto assess the effectiveness of software clustering algorithms.
On the feasibility of computing discrete logarithms using Adleman's subexponential algorithm
Authors: Tore Herlestam
Venue: ACM SIGACT News (1983)

Some public key distribution systems, based on the difficulties in computing logarithms modulo a large prime, have been alleged to be insecure because of a statement that any logarithm modulo a 200 bit prime can be computed within a reasonable time by means of a subexponential algorithm due to Adleman.In this commentary said algorithm is examined from an algebraic and number-theoretical point of view. The scrutiny shows that the algebraic model for the algorithm contains several traps which seem to be hard to circumvent, and also, not least, that the presupposed abundance of so called round numbers will not be at hand in the computationally interesting cases.Hence it is concluded that the algorithm cannot be a serious threat to the mentioned public key distribution systems.
High Throughput Byzantine Fault Tolerance
Authors: Ramakrishna Kotla, Mike Dahlin
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

This paper argues for a simple change to Byzantine FaultTolerant (BFT) state machine replication libraries. TraditionalBFT state machine replication techniques providehigh availability and security but fail to provide highthroughput. This limitation stems from the fundamentalassumption of generalized state machine replicationtechniques that all replicas execute requests sequentiallyin the same total order to ensure consistency acrossreplicas. We propose a high throughput Byzantine fault tolerantarchitecture that uses application-specific informationto identify and concurrently execute independentrequests. Our architecture thus provides a generalway to exploit application parallelism in order toprovide high throughput without compromising correctness.Although this approach is extremely simple, it yieldsdramatic practical benefits. When sufficient applicationconcurrency and hardware resources exist, CBASE,our system prototype, provides orders of magnitude improvementsin throughput over BASE, a traditional BFTarchitecture. CBASE-FS, a Byzantine fault tolerant file systemthat uses CBASE, achieves twice the throughput ofBASE-FS for the IOZone micro-benchmarks even in a configurationwith modest available hardware parallelism.
Teachers' perceptions of the effectiveness of ICT-competence training
Authors: Despina Galanouli, Colette Murphy, John Gardner
Venue: Computers Education (2004)

Over several decades the major thrust in the school sector of countries across the world has been the search for ways in which teachers can be convinced that ICT should be an integral part of their teaching strategy. Various approaches have been tried including the dissemination of good practice and the investment in infrastructure and equipment. Prominent among the strategies are training programmes designed to raise skill levels and foster positive attitudes to computers among teachers. This paper takes the latter of these and considers teachers' perceptions of computers and one specific national initiative, i.e., the New Opportunities Fund (NOF) training for all UK teachers. This initiative, costing £230 million overall, provided training in all four countries of the UK. In the research reported here, a sample of 900 teachers from primary (5-11 years) and secondary (11-16/18years) schools in Northern Ireland was surveyed and yielded over 450 responses. The survey sought their views on a number of educational technology-related issues and this paper deals specifically with their responses on items relating to NOF training. The data included narrative commentaries from the teachers on their experiences with an attitude scale that allowed comparisons of the different types of respondents, e.g., male/female and secondary/primary. A selection of the results is presented in this paper along with a discussion of their implications for policy and practice. In summary, the results suggest that NOF training has had a measure of success in increasing teachers' confidence in using computers in their teaching but that this has been tempered by a considerable degree of negative reaction to form and content of the training.