ppxscal/embedding_network huggingface dataset:
Block-type-decodable encoders for constrained systems
Authors: Brian H. Marcus
Venue:  (2003)

In most recording channels, arbitrary user data is encoded into constrained sequences to improve the performance of storage systems. In this work, we focus on three classes of encoders: block, block-decodable, and deterministic. The decoders for block and block-decodable encoders decide the current input symbol based on only the current codeword; thus the error propagation is limited to one block. In contrast, deterministic encoders do not have this property. However, it is much more tractable to compute optimal code rates of deterministic encoders than block and block-decodable encoders. We call these encoders block-type-decodable encoders. For a constrained system presented by a deterministic graph, the problem of designing a block-type-decodable encoder can be solved by selecting a subset of states of the graph to be used as encoder states. Such a subset is known as a set of principal states. Our goal is to find an optimal set of principal states that yields the highest code rate. We study the relationship between optimal sets of principal states at a finite block length and asymptotically large block length. Specifically, we apply Perron-Frobenius theory to show that for a primitive constrained system and a large enough block length, any optimal set of principal states is also asymptotically optimal. Bounds on block length that guarantee this relationship are given. Characterization of asymptotically optimal sets of principal states is also presented. An important class of constraints for high-density disk drives is the class of maximum transition run (MTR) systems. Its structure allows us to compute optimal sets of principal states for all block lengths by enumeration. Finally, we extend our study to the class of bounded-delay-encodable block-decodable (BDB) encoders, which encode by using a look-ahead technique. In some circumstances, this encoder achieves a higher rate than any block-type-decodable encoder and still limits the error propagation to one block. We characterize asymptotically optimal BDB encoders for primitive constraints. For the classes of runlength-limited (RLL) and MTR systems, we investigate how the optimal code rate varies with look-ahead.
Representations of Regular Ideals in Finite Automata
Authors: I. K. Rystsov
Venue: Cybernetics and Systems Analysis (2003)

Regular ideals of a free monoid are shown to be characterized by weak (noninitial) representations in finite automata. The class of kernel ideals is also shown to be invariant under the action of several automata functors and to be equal to the class of zero ideals.
3/2-approximation for two-machine no-wait flowshop scheduling with availability constraints
Authors: T. C. Edwin Cheng, Zhaohui Liu
Venue: Information Processing Letters (2003)

We consider in this paper the two-machine no-wait flowshop problem in which each machine may have an unavailable interval. We present 3/2-approximation algorithms for the problem when the unavailable interval is imposed on only one machine, or the unavailable intervals on the two machines overlap. These algorithms improve on existing results.
Energy-Efficient Design for Highly Associative Instruction Caches in Next-Generation Embedded Processors
Authors: Juan Luis Aragon, Dan Nicolaescu, Alex Veidenbaum, Ana-Maria Badulescu
Venue: Proceedings of the conference on Design, automation and test in Europe - Volume 2 (2004)

This paper proposes a low-energy solution for CAM-based highly associative I-caches using a segmented wordline and a predictor-based instruction fetch mechanism. Not all instructions in a given I-cache fetch are used due to branches. The proposed predictor determines which instructions in a cache access will be used and does not fetch any other instructions. Results show an average I-cache energy savings of 44% over the baseline case and 6% over thesegmented case with no negative impact on performance.
Keyword-based queries over web databases
Authors: Altigran S. da Silva, Pável Calado, Rodrigo C. Vieira, Alberto H. F. Laender, Bertheir A. Ribeiro-Neto
Venue: Effective databases for text & document management (2003)

In this chapter, we propose an approach to using keywords (as in a Web search engine) for querying databases over the Web. The approach is based on a Bayesian network model and provides a suitable alternative to the use of interfaces based on multiple forms with several fields. Two major steps are involved when querying a Web database using this approach. First, structured (database-like) queries are derived from a query composed only of the keywords specified by the user. Next, the structured queries are submitted to a Web database, and the retrieved results are presented to the user as ranked answers. To demonstrate the feasibility of the approach, a simple prototype Web search system based on the approach is presented. Experimental results obtained with this system indicate that the approach allows for accurately structuring the user queries and retrieving appropriate answers with minimum intervention from the user.
Fighting the spam wars: A remailer approach with restrictive aliasing
Authors: Pawel Gburzynski, Jacek Maitan
Venue: ACM Transactions on Internet Technology (TOIT) (2004)

We present an effective method of eliminating unsolicited electronic mail (so-called spam) and discuss its publicly accessible prototype implementation. A subscriber to our system is able to obtain an unlimited number of aliases of his/her permanent (protected) E-Mail address to be handed out to parties willing to communicate with the subscriber. It is also possible to set up publishable aliases, which can be used by human correspondents to contact the subscriber, while being useless to harvesting robots and spammers. The validity of an alias can be easily restricted to a specific duration in time, a specific number of received messages, a specific population of senders, and/or in other ways. The system is fully compatible with the existing E-Mail infrastructure and can be immediately accessed via any standard E-Mail client software (MUA). It can be easily deployed at any institution or organization running its private E-Mail server (MTA) with a trivial modification to that server. Our system offers a simple method to salvage the existing population of E-Mail addresses while eliminating all spam aimed at them.
Dynamic Noise Margin: Definitions and Model
Authors: Li Ding, Pinaki Mazumder
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

Dynamic noise analysis is greatly needed in place of traditionalstatic noise analysis due to the ever increasinglystringent design requirement for VLSI chips based on verydeep submicron process technology. In this paper, we proposecomplete and self-consistent dynamic noise margindefinitions to reduce the pessimism of conventional staticnoise margin based noise analysis. A simple and accuratedynamic noise margin model is then developed based on anew figure of merit, which is the ratio between the inputnoise duration and the sum of gate load capacitance andgate intrinsic capacitance. An efficient dynamic noise marginbased noise analysis method is presented.
The CMU Pose, Illumination, and Expression Database
Authors: Terence Sim, Simon Baker, Maan Bsat
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2003)

Abstract--In the Fall of 2000, we collected a database of more than 40,000 facial images of 68 people. Using the Carnegie Mellon University 3D Room, we imaged each person across 13 different poses, under 43 different illumination conditions, and with four different expressions. We call this the CMU Pose, Illumination, and Expression (PIE) database. We describe the imaging hardware, the collection procedure, the organization of the images, several possible uses, and how to obtain the database.
Real-time goal-mouth detection in MPEG soccer video
Authors: Kongwah Wan, Xin Yan, Xinguo Yu, Changsheng Xu
Venue: Proceedings of the eleventh ACM international conference on Multimedia (2003)

We report our work in real-time detection of goal-mouth appearances in MPEG soccer video. Processing on sub-optimal quality images after MPEG-decoding, the system constrains the Hough Transform-based line-mark detection to only the dominant green regions typically seen in soccer video. The vertical goal-posts and horizontal goal-bar are then isolated by color-based region (pole)-growing. We demonstrate its application for quick video browsing and virtual content insertion. Extensive test over a large data set of about 15 hours of MPEG-1 soccer video @1.15Mbps, CIF-resolution, shows the robustness of our method.
Computer science education for students training to be secondary teachers
Authors: Terry J. Frederick
Venue: ACM SIGCUE Outlook (1975)

This paper reports on some efforts to provide computer science training for potential teachers in the secondary schools. For those who wish to teach computing concepts, a program consisting of six courses (18 semester hours) of computer science that includes (1) computing concepts studied in the context of both high-level and assembly languages, (2) an exposure to the continuum of applications of computers to education and (3) pertinent electives relative to the students major discipline is outlined. Included are discussions of some relevant issues, rationale for directions taken and specific details about the program.
A Macromodelling Methodology for Efficient High-Level Simulation of Substrate Noise Generation
Authors: Luis Elvira, Ferran Martorell, Xavier Aragonés, José Luis González
Venue: Proceedings of the conference on Design, automation and test in Europe - Volume 2 (2004)

Efficient prediction of the substrate noise generated by digital sections is currently a major challenge in System-on-a-Chip design. In this paper a macromodel to accurately and efficiently predict the substrate noise generated by digital standard cells is presented. The macromodel accuracy is demonstrated for some simple circuits.
What's going on?: discovering what children understand about handwriting recognition interfaces
Authors: Janet C. Read, Stuart MacFarlane, Chris Casey
Venue: Proceedings of the 2003 conference on Interaction design and children (2003)

When people use interactive technology, they construct a 'mental model' of the processes that are going on. This model assists the user in error repair and in task completion. The mental models that children have of computer systems are known to be brittle and incomplete. This paper describes how three different methods - structured interview, questionnaire, and talk back, were used with 7 and 8-year-old children to identify children's mental models of a handwriting-recognition based interface. The time taken by both the child and the researcher, the insights reported by the children, and the ease of use of each of the three methods is reported. The three methods are then compared, both in terms of cost/benefit and with relation to the influence of the researcher in the process. The paper concludes that the interview and questionnaire were both effective in this study, and that questionnaires can be surprisingly informative with children of this age.
Corrosion inhibition by self-assembled monolayers for enhanced wire bonding on Cu surfaces
Authors: Caroline M. Whelan, Michael Kinsella, Laureen Carbonell, Hong Meng Ho, Karen Maex
Venue: Microelectronic Engineering (2003)

Corrosion inhibition by thiol-derived self-assembled monolayers (SAMs) on Cu surfaces has been characterised using contact angle measurements, X-ray photoelectron spectroscopy, voltammetry, and thermal desorption spectroscopy. Factors influencing SAM formation were investigated to develop an optimised wafer level process. XPS confirms the formation of thiolate species bonded to a mixed metallic Cu and cuprous oxide surface. Stability studies as a function of temperature and electrochemical potential demonstrate promising passivation properties. The feasibility of exploiting SAMs in microelectronics applications was demonstrated by the enhancement of Cu wire bonding onto Cu bond pads.
Combinatorial properties of shifted complexes
Authors: Caroline J. Klivans
Venue:  (2003)

In this thesis we study the class of shifted simplicial complexes. A simplicial complex on n nodes is shifted if there exists a labelling of the nodes by 1 through n such that for any face, replacing any node of the face with a node of smaller label results in a collection which is also a face. A primary motivation for considering shifted complexes is a procedure called shifting. Shifting associates a shifted complex to any simplicial complex in a way which preserves meaningful information, while simplifying the structure of the complex. For example, shifting preserves the f-vector of a complex but always reduces the topology to a wedge of spheres. Shifting has proved to be a successful tool for answering questions regarding f-vectors. While most of the previous results on shifted complexes are algebraic or topological in nature, we explore the combinatorics of shifted complexes. We give intrinsic characterization theorems for shifted complexes and shifted matroid complexes. In addition, we show results on the enumeration of shifted complexes and connections to various combinatorial structures. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
The role of modeling in computational science education
Authors: W. Wiechert
Venue: Future Generation Computer Systems (2003)

Modeling and simulation skills are two core competences of computational science and thus should be a central part of any curriculum. While there is a well-founded methodology for the design of simulation algorithms today the teaching of modeling skills carries some intrinsic problems. The reason is that modeling is still partly an art and partly a science. As an important consequence for university education, the concepts for teaching modeling must be quite different from those for teaching simulation algorithms. Experiences made with the courses on 'Modeling and Simulation' at the University of Siegen are summarized and some general concepts for the teaching of modeling skills are presented. In particular, three practical approaches to modeling education are discussed with several examples.
Rigorous Shadowing of Numerical Solutions of Ordinary Differential Equations by Containment
Authors: Wayne B. Hayes, Kenneth R. Jackson
Venue: SIAM Journal on Numerical Analysis (2003)

An exact trajectory of a dynamical system lying close to a numerical trajectory is called a shadow. We present a general-purpose method for proving the existence of finite-time shadows of numerical ODE integrations of arbitrary dimension in which some measure of hyperbolicity is present and there are either 0 or 1 expanding modes, or 0 or 1 contracting modes. Much of the rigor is provided automatically by interval arithmetic and validated ODE integration software that is freely available. The method is a generalization of a previously published containment process that was applicable only to two-dimensional maps. We extend it to handle maps of arbitrary dimension with the above restrictions, and finally to ODEs. The method involves building n-cubes around each point of the discrete numerical trajectory through which the shadow is guaranteed to pass at appropriate times. The proof consists of two steps: first, the rigorous computational verification of a simple geometric property, which we call the inductive containment property, and second, a simple geometric argument showing that this property implies the existence of a shadow. The computational step is almost entirely automated and easily adaptable to any ODE problem. The method allows for the rescaling of time, which is a necessary ingredient for successfully shadowing ODEs. Finally, the method is local, in the sense that it builds the shadow inductively, requiring information only from the most recent integration step, rather than more global information typical of several other methods. The method produces shadows of comparable length and distance to all currently published results. Finally, we conjecture that the inductive containment property implies the existence of a shadow without restriction on the number of expanding and contracting modes, although proof currently eludes us.
Domain equations for probabilistic processes
Authors: Christel Baier, Marta Kwiatkowska
Venue: Mathematical Structures in Computer Science (2000)

In this paper we consider Milner's calculus CCS enriched by a probabilistic choice operator. The calculus is given operational semantics based on probabilistic transition systems. We define operational notions of preorder and equivalence as probabilistic extensions of the simulation preorder and the bisimulation equivalence respectively. We extend existing category-theoretic techniques for solving domain equations to the probabilistic case and give two denotational semantics for the calculus. The first, &lsquo;smooth&rsquo;, semantic model arises as a solution of a domain equation involving the probabilistic powerdomain and solved in the category CONT&bottom; of continuous domains. The second model also involves an appropriately restricted probabilistic powerdomain, but is constructed in the category CUM of complete ultra-metric spaces, and hence is necessarily &lsquo;discrete&rsquo;. We show that the domain-theoretic semantics is fully abstract with respect to the simulation preorder, and that the metric semantics is fully abstract with respect to bisimulation.
Quadratic spline wavelets with arbitrary simple knots on the sphere
Authors: El Bachir Ameur, Driss Sbibih
Venue: Journal of Computational and Applied Mathematics (2004)

In this paper, we extend the method for fitting functions on the sphere, described in Lyche and Schumaker (SIAM J. Sci. Comput. 22 (2) (2000) 724) to the case of nonuniform knots. We present a multiresolution method leading to -functions on the sphere, which is based on tensor products of quadratic polynomial splines and trigonometric splines of order three with arbitrary simple knot sequences. We determine the decomposition and reconstruction matrices corresponding to the polynomial and trigonometric spline spaces. We describe the tensor product decomposition and reconstruction algorithms in matrix forms which are convenient for the compression of surfaces. We give the different steps of computer implementation and finally we present a test example by using two knot sequences: a uniform one and a sequence of Chebyshev points.
Constructivist Learning with Participatory Examinations
Authors: Dezhi Wu, Michael Bieber, Starr Roxanne Hiltz, Hyo-Joo Han
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 1 - Volume 1 (2004)

Can we improve the examination process, making it more enjoyable and increasing perceived learning? The participatory exam process provides opportunities for students to learn from creating, reading, answering and grading exam questions. An on-line asynchronous learning network system facilitates the process. This paper presents the process framework, our research model and experimental results. A majority of students preferred the participatory exam and believed that it increased their learning.
Towards a Grid Management System for HLA-Based Interactive Simulations
Authors: Katarzyna Zajac, Marian Bubak, Maciej Malawski, Peter Sloot
Venue: Proceedings of the Seventh IEEE International Symposium on Distributed Simulation and Real-Time Applications (2003)

This paper presents the design of a system that supports execution of HLA distributed interactive simulations in an unreliable Grid environment. The design of the architecture is based on the OGSA concept that allows for modularity and compatibility with Grid Services already being developed. First of all, we focus on the part of the system which is responsible for migration of a HLA-connected component or components of the distributed application in the Grid environment. We present a runtime support library for easily plugging HLA simulations into the Grid Services Framework. We also present the impact of execution management (namely migration) on overall system performance.
Building knowledge discovery into a geo-spatial decision support system
Authors: Sherri K. Harms, Jitender Deogun, Steve Goddard
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

The emergence of remote sensing, scientific simulation, telescope scanning, and other survey technologies has dramatically enhanced our capabilities to collect spatio-temporal data. However, the explosive growth in data makes the management, analysis, and use of data difficult and expensive. In decision support applications with spatio-temporal data, it is important to study the temporal relationships of the parameters that influence the decision. Because multiple spatio-temporal data sets contain volumes of data, and often there is a delay between the occurrence of an event and its influence on the dependent variables, finding interesting patterns can be difficult.This paper presents a layered architecture for a distributed GDSS that uses temporal rule discovery to aid the decision-making process. Data mining algorithms are used to identify temporal relationships between multiple spatio-temporal data sets where time lags may exist between the related events. These algorithms allow the user to specify target events, to prune rules that are not of interest to the current decision-making problem. A geo-spatial decision support system for drought risk management is used to demonstrate the effectiveness of building knowledge discovery into a GDSS.
Incompressible limits of lattice Boltzmann equations using multiple relaxation times
Authors: Paul J. Dellar
Venue: Journal of Computational Physics (2003)

Lattice Boltzmann equations using multiple relaxation times are intended to be more stable than those using a single relaxation time. The additional relaxation times may be adjusted to suppress non-hydrodynamic modes that do not appear directly in the continuum equations, but may contribute to instabilities on the grid scale. If these relaxation times are fixed in lattice units, as in previous work, solutions computed on a given lattice are found to diverge in the incompressible (small Mach number) limit. This non-existence of an incompressible limit is analysed for an inclined one dimensional jet. An incompressible limit does exist if the non-hydrodynamic relaxation times are not fixed, but scaled by the Mach number in the same way as the hydrodynamic relaxation time that determines the viscosity.
Electrical properties of W/Si interfaces with embedded Ge/Si islands
Authors: A. Hattab, F. Meyer, Vy Yam, D. Bouchier, R. Meyer, O. Schneegans, C. Clerc
Venue: Microelectronic Engineering (2003)

In this work, we investigated electrical and morphological properties of W/p-type Si Schottky diodes with intentional inhomogeneities introduced by macroscopic Ge-islands embedded beneath the interface. The Si-cap layer thickness (or the island-distance to the interface) was progressively reduced by successive chemical etching cycles. Electrical characterizations were achieved through reverse current-voltage (I-V) at room temperature and forward I-V measurements as a function of the temperature. In parallel, Rutherford backscattering spectroscopy analyses were performed to follow the Si-cap/Ge islands chemical thinning down with increasing the number of etching cycles. In addition, the comparison of topographical and electrical properties of the etched silicon-cap layer was carried out by conductive atomic force microscopy analyses with a nanometer-scale resolution. Our results indicate that the areas on the top of islands exhibit lower resistance than those which covered the wetting layer. This lateral variation of resistance at the surface of the semiconductor may correspond to Schottky barrier height inhomogeneities observed on broad area I-V characteristics of Schottky contacts.