ppxscal/embedding_network huggingface dataset:
Improving Data Prefetching Efficacy in Multimedia Applications
Authors: Rita Cucchiara, Andrea Prati, Massimo Piccardi
Venue: Multimedia Tools and Applications (2003)

The workload of multimedia applications has a strong impact on cache memory performance, since the locality of memory references embedded in multimedia programs differs from that of traditional programs. In many cases, standard cache memory organization achieves poorer performance when used for multimedia. A widely-explored approach to improve cache performance is hardware prefetching, which allows the pre-loading of data in the cache before they are referenced. However, existing hardware prefetching approaches are unable to exploit the potential improvement in performance, since they are not tailored to multimedia locality. In this paper we propose novel effective approaches to hardware prefetching to be used in image processing programs for multimedia. Experimental results are reported for a suite of multimedia image processing programs including MPEG-2 decoding and encoding, convolution, thresholding, and edge chain coding.
A topology-shape-metrics approach for the automatic layout of UML class diagrams
Authors: Markus Eiglsperger, Michael Kaufmann, Martin Siebenhaller
Venue: Proceedings of the 2003 ACM symposium on Software visualization (2003)

Class diagrams are among the most popular visualizations for object oriented software systems and have a broad range of applications. In many settings it is desirable that the placement of the diagram elements is determined automatically, especially when the diagrams are generated automatically which is usually the case in reverse engineering. For this reason the automatic layout of class diagram gained importance in the last years. Current approaches for the automatic layout of class diagrams are based on the hierarchic graph drawing paradigm. These algorithms produce good results for class diagrams with large and deep structural information, i.e., diagrams with a large and deep inheritance hierarchy. However, they do not perform satisfactorily in absence of this information. We propose in this work a new algorithm for automatic layout of class diagram which is based on the topology-shape-metrics approach. The algorithm is an adaption of sophisticated graph drawing algorithms which have proven their effectiveness in many applications. The algorithm works as well for class diagrams with rich structural information as for class diagrams with few or no structural information. It improves therefore the existing algorithms significantly. An implementation of the algorithm is used in the reverse engineering tool JarInspector.
Technology, organizational change and virtual libraries
Authors: Ardis Hanson, Bruce Lubotsky Levin, Susan Heron, Merilyn Burke
Venue: Building a virtual library (2003)

Change has become a way of life for most organizations in the 21st century. In order to withstand profound change, an organisation must be flexible and incorporate the ability to adapt and respond to its external environment and its many stakeholders (Kanter, Stein, & Tick, 1992). At the same time, in an era of increasing fiscal constraints, new technologies, and an explosion of information, informatics plays an increasingly important and prominent role in society, in knowledge exchange, in communication, and in commerce between organizations. Accordingly, the most remarkable opportunities and challenges have emerged within academic libraries with regard to the incorporation of technology into daily functioning. Academic libraries only achieve real change when every person, from staff to administrator, is willing to examine functions, strategies, goals, and processes and to participate in free discussions of the critical issues. This chapter examines such a landmark shift in an organization's operation and culture with the creation of a "virtual library" at an urban university. It will review the planning, development, and implementation process of the virtual library, It will also examine the barriers and successes within the organizational role of a multi-campus, autonomous university library system. The chapter will conclude with a discussion of future issues and opportunities for the role of technology in organizations and organizational change.
A unified approach to the analysis of Horton-Strahler parameters of binary tree structures
Authors: Markus E. Nebel
Venue: Random Structures Algorithms (2002)

The Horton-Strahler number naturally arose from problems in various fields, e.g., geology, molecular biology and computer science. Consequently, detailed investigations of related parameters for different classes of binary tree structures are of interest. This paper shows one possibility of how to perform a mathematical analysis for parameters related to the Horton-Strahler number in a unified way such that only a single analysis is needed to obtain results for many different classes of trees. The method is explained by the examples of the expected Horton-Strahler number and the related rth moments, the average number of critical nodes, and the expected distance between critical nodes.
A real-time Java server for real-time mach
Authors: Akihiko Miyoshi, Takuro Kitayama, Hideyuki Tokuda
Venue: Engineering of distributed control systems (2001)

We have developed a real-time Java1 server on the Real-Time Mach micro-kernel which is suitable for embedded systems and distributed real-time systems. By implementing it as a user-level server on Real-Time Mach, applications such as WWW browsers and embedded applications can both execute Java byte codes. In this paper, we describe the real-time issues in Java and the architecture of our Java server. The real-time extension of the Java server and Java threads using kernel-level threads was also evaluated.
The Performance Presumption
Authors: Steve Vinoski
Venue: IEEE Internet Computing (2003)

Choosing the right middleware means first determining the qualities that matter most for your application, and then evaluating different types of middleware to see how well they meet your requirements. Because of the difficulties involved in thoroughly and accurately evaluating middleware, however, consumers routinely take shortcuts.
Phrase sets for evaluating text entry techniques
Authors: I. Scott MacKenzie, R. William Soukoreff
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

In evaluations of text entry methods, participants enter phrases of text using a technique of interest while performance data are collected. This paper describes and publishes (via the internet) a collection of 500 phrases for such evaluations. Utility programs are also provided to compute statistical properties of the phrase set, or any other phrase set. The merits of using a pre-defined phrase set are described as are methodological considerations, such as attaining results that are generalizable and the possible addition of punctuation and other characters.
Optimization based passive constrained fitting
Authors: Carlos P. Coelho, Joel R. Phillips, L. Miguel Silveira
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Verification of contemporary integrated circuits requires accurate modeling of high-frequency effects in all passive component sub-systems. Often, descriptions of those subsystems are only available in the frequency-domain. In this paper, we propose a simple, scalar, constrained-passive rational approximation scheme that incorporates a grid-based test for strict positive realness. In contrast to similar recent work based on convex optimization and the positive real lemma, the methodology is potentially more efficient, since it does not introduce a quadratic number of auxiliary variables, is potentially more accurate, since pole locations can be re-adjusted during the optimization, but possibly less reliable, since it relies on the solution of optimization problems that are not convex. There-fore, because of the use of local constrained non-convex optimization, the generation of feasible initial guesses is also considered.
Non-linear evolution using optimal fourth-order strong-stability-preserving Runge-Kutta methods
Authors: Raymond J. Spiteri, Steven J. Ruuth
Venue: Mathematics and Computers in Simulation (2003)

Strong-stability-preserving (SSP) time discretization methods (also known as total-variation-diminishing or TVD methods) are popular and effective algorithms for the simulation of partial differential equations having discontinuous or shock-like solutions. Optimal SSP Runge-Kutta (SSPRK) schemes have been previously found for methods with up to five stages and up to fourth order. In this paper, we present new optimal fourth-order SSPRK schemes with mild storage requirements and up to eight stages. We find that these schemes are ultimately more efficient than the known fourth-order SSPRK schemes because the increase in the allowable time-step more than offsets the added computational expense per step. We demonstrate these efficiencies on a pair of scalar conservation laws.
Analysis of a Least Recently Used Cache Management Policy for Web Browsers
Authors: Vijay S. Mookerjee, Yong Tan
Venue: Operations Research (2002)

Experience shows that document caching by a web browser is a cheap and effective way to improve the performance of the World Wide Web. This study analyzes a LRU (Least Recently Used) policy for cache management in a web browser. In this policy, the cache is filled with documents based upon a document's "age," defined as the time elapsed since the document was last accessed. The user's preference for a document is modeled as a general function that declines with the document's age. Two popular measures--the expected delay per document access, and the hit-ratio--are used to evaluate the LRU policy. Unlike many previous studies that evaluate caching policies using simulation methods, this study derives analytical expressions to evaluate performance. The study also presents an approximate, easy-to-compute method to evaluate performance. Numerical tests show this approximation to be extremely accurate. A variety of other numerical results are presented that help describe the behavior ofthe LRU policy under different situations (e.g., when the documents need to be updated periodically). We also compare the LRU policy with other caching policies (both static and dynamic) for small problems. Our comparison suggests that finding a good caching policy that is conscious of document size and delay may be difficult.
PCA-based branch and bound search algorithms for computing K nearest neighbors
Authors: Win D'haes, Dirk van Dyck, Xavier Rodet
Venue: Pattern Recognition Letters (2003)

In this paper, the efficiency of branch and bound search algorithms for the computation of K nearest neighbors is studied. The most important aspects that influence the efficiency of the search algorithm are: (1) the decomposition method, (2) the elimination rule, (3) the traversal order and (4) the level of decomposition. First, a theoretical derivation of an efficient decomposition method based on principal component analysis is given. Then, different elimination rules and traversal orders are combined resulting in ten different search algorithms. Since the efficiency is strongly dependent on the level of decomposition, this user specified parameter is optimized first. This optimization is realized by a probabilistic model that expresses the total computation time in function of the node traversal cost and the distance computation cost. All comparisons are based on the total computation time for the optimal level of decomposition.
Variety Seeking, Purchase Timing, and the "Lightning Bolt" Brand Choice Model
Authors: Roman Kapuscinski, Sridhar Tayur, Pradeep K. Chintagunta
Venue: Management Science (1999)

The "Lightning Bolt" (LB) model provides a comprehensive framework for accommodating the effects of habit persistence, unobserved heterogeneity, and state dependence on household brand choice behavior. This paper presents a discrete, dynamic brand-choice model that belongs to the LB class of models. We propose a method for incorporating the effects of variety seeking into the LB model formulation. The proposed formulation explicitly links brand choice and purchase timing behavior via the effect of state dependence. This state-dependence based linkage between brand choice and purchase timing comes about due to the attribute satiation notion associated with household variety seeking behavior. Empirical implementation of the model specification req uires recognizing that interpurchase times, like brand choices, also depend upon marketing variables and household characteristics. A hazard model is specified to capture this relationship. Empirical results are presented using household-level data for two different products. Our results reveal the following. (1) State dependence effects decline over time. Hence, households' brand switching and repeat purchase probabilities vary over time, independent of any variation in marketing mix activities. (2) Accounting for the effects of marketing variables on interpurchase times may be important when empirically estimating the proposed model. While the nature of substantive implications is largely unchanged, the magnitudes of the different effects are nevertheless affected. (3) We find evidence for purchase reinforcement (and its effects declining over time), but no evidence for attribute satiation based variety seeking behavior. (4) A comparison of the model's predictive ability with those from two extant specifications reveals that the proposed model outperforms rival specifications.
Self-Organized Public-Key Management for Mobile Ad Hoc Networks
Authors: Srdjan Čapkun, Levente Buttyán, Jean-Pierre Hubaux
Venue: IEEE Transactions on Mobile Computing (2003)

In contrast with conventional networks, mobile ad hoc networks usually do not provide online access to trusted authorities or to centralized servers, and they exhibit frequent partitioning due to link and node failures and to node mobility. For these reasons, traditional security solutions that require online trusted authorities or certificate repositories are not well-suited for securing ad hoc networks. In this paper, we propose a fully self-organized public-key management system that allows users to generate their public-private key pairs, to issue certificates, and to perform authentication regardless of the network partitions and without any centralized services. Furthermore, our approach does not require any trusted authority, not even in the system initialization phase.
Temporal concurrent constraint programming: applications and behavior
Authors: Mogens Nielsen, Frank D. Valencia
Venue: Formal and natural computing (2002)

The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied reflect the reactive interactions between concurrent constraint processes and their environment, as well as internal interactions between individual processes. Relationships between the suggested notions are studied, and they are all proved to be decidable for a substantial fragment of the calculus. Furthermore, the expressive power of this fragment is illustrated by examples.
On the tool-path optimization of a milling robot
Authors: S. S. Makhanov, D. Batanov, E. Bohez, K. Sonthipaumpoon, W. Anotaipaiboon, M. Tabucanon
Venue: Computers and Industrial Engineering (2002)

We present a new approach to tool-path optimization of milling robots based on a global interpolation of the required surface by a virtual surface composed from tool trajectories. The procedure combines inverse kinematics techniques and a variational gridding method endowed with constraints related to the required scallop height. We demonstrate the capability of the proposed technique to generate a tool-path for workpieces with complex geometries comprising 'islands' or boundaries with sharp edges requiring a combined spiral-zigzag pattern.Our technique provides a significant increase in the accuracy of milling.
Dynamic frequency and voltage control for a multiple clock domain microarchitecture
Authors: Greg Semeraro, David H. Albonesi, Steven G. Dropsho, Grigorios Magklis, Sandhya Dwarkadas, Michael L. Scott
Venue: Proceedings of the 35th annual ACM/IEEE international symposium on Microarchitecture (2002)

We describe the design, analysis, and performance of an on--line algorithm to dynamically control the frequency/voltage of a Multiple Clock Domain (MCD) microarchitecture. The MCD microarchitecture allows the frequency/voltage of microprocessor regions to be adjusted independently and dynamically, allowing energy savings when the frequency of some regions can be reduced without significantly impacting performance.Our algorithm achieves on average a 19.0% reduction in Energy Per Instruction (EPI), a 3.2% increase in Cycles Per Instruction (CPI), a 16.7% improvement in Energy--Delay Product, and a Power Savings to Performance Degradation ratio of 4.6. Traditional frequency/voltage scaling techniques which apply reductions globally to a fully synchronous processor achieve a Power Savings to Performance Degradation ratio of only 2--3. Our Energy--Delay Product improvement is 85.5% of what has been achieved using an off--line algorithm. These results were achieved using a broad range of applications from the MediaBench, Olden, and Spec2000 benchmark suites using an algorithm we show to require minimal hardware resources.
A Survey of Optimization Models for Train Routing and Scheduling
Authors: Jean-Francois Cordeau, Paolo Toth, Daniele Vigo
Venue: Transportation Science (1998)

The aim of this paper is to present a survey of recent optimization models for the most commonly studied rail transportation problems. For each group of problems, we propose a classification of models and describe their important characteristics by focusing on model structure and algorithmic aspects. The review mainly concentrates on routing and scheduling problems since they represent the most important portion of the planning activities performed by railways. Routing models surveyed concern the operating policies for freight transportation and railcar fleet management, whereas scheduling models address the dispatching of trains and the assignment of locomotives and cars. A brief discussion of analytical yard and line models is also presented. The emphasis is on recent contributions, but several older yet important works are also cited.
A Note on the Single Leg, Multifare Seat Allocation Problem
Authors: Michael Z. F. Li, Tae H. Oum
Venue: Transportation Science (2002)

In this note, we attempt to prove the equivalence of the optimality conditions from three well-known existing models that deal with the seat allocation problem for a single leg, multifare flight with independent fare class demands.
The complex spline approximation of singular integral operators over an open arc
Authors: Yong Jia Xu
Venue: Journal of Approximation Theory (2002)

This paper mainly considers the smooth complex spline approximation of Cauchy-type integral operators over an open arc. First, the smoothness of the operators is investigated, then some properties of complex splines are discussed, and finally the error estimates of the approximation are given.
An Approximation Algorithm for Minimum Convex Cover with Logarithmic Performance Guarantee
Authors: Stephan J. Eidenbenz, Peter Widmayer
Venue: SIAM Journal on Computing (2003)

The problem MINIMUM CONVEX COVER of covering a given polygon with a minimum number of (possibly overlapping) convex polygons is known to be NP-hard, even for polygons without holes [J. C. Culberson and R. A. Reckhow, J. Algorithms, 17 (1994), pp. 2--44]. We propose a polynomial-time approximation algorithm for this problem for polygons with or without holes that achieves an approximation ratio of O(log n), where n is the number of vertices in the input polygon. To obtain this result, we first show that an optimum solution of a restricted version of this problem, where the vertices of the convex polygons may lie only on a certain grid, contains at most three times as many convex polygons as the optimum solution of the unrestricted problem. As a second step, we use dynamic programming to obtain a convex polygon which is maximum with respect to the number of "basic triangles" that are not yet covered by another convex polygon. We obtain a solution that is at most a logarithmic factor off the optimum by iteratively applying our dynamic programming algorithm. Furthermore, we show that MINIMUM CONVEX COVER is APX-hard; i.e., there exists a constant $\delta >0$ such that no polynomial-time algorithm can achieve an approximation ratio of $1+\delta$. We obtain this result by analyzing and slightly modifying an already existing reduction [J. C. Culberson and R. A. Reckhow, J. Algorithms, 17 (1994), pp. 2--44].
The interfacing of Mathematica with a variety of computing environments
Authors: Mufid Abudiab
Venue: Journal of Computing Sciences in Colleges (2002)

It has been an exciting experience introducing major changes to the teaching of the Ordinary Differential Equations (ODE) class at my school. The recommended teaching methodology was enhanced by the use of technology in a lab setting (Mathematica) in conjunction with cooperative learning [1]. Working with Mathematica has given me the opportunity to put its unique potential to practice while exploring other avenues that increase its capabilities in interfacing with other environments. In this paper, I share with my colleagues my experience in working with Mathematica and some information regarding how it communicates (using MathLink and other tools) with certain well-established computing environments like C++ and FORTRAN.
Scale continuum approach in biomechanics: a simple simulation of a microstructural control of tissues' stiffness
Authors: Miroslav Holeček, Olga Červená, Fanny Poirier
Venue: Mathematics and Computers in Simulation (2003)

We construct a simple model of an elastic material whose stiffness can be effectively controlled by an appropriately chosen set of microstructural parameters. The model is based on ideas of the scale-dependent continuum description and might play an important role in modelling of muscle tissues in biomechanics.
Image enhancement and minutiae matching in fingerprint verification
Authors: Yuliang He, Jie Tian, Xiping Luo, Tanghui Zhang
Venue: Pattern Recognition Letters (2003)

Fingerprint image enhancement and minutiae matching are two key steps in an automatic fingerprint identification system. In this paper, we develop a fingerprint image enhancement algorithm based on orientation fields; According to the principles of Jain et al.'s matching algorithm, we also introduce ideas along the following three aspects: introduction of ridge information into the minutiae matching process in a simple but effective way, which solves the problem of reference point pair selection with low computational cost; use of a variable sized bounding box to make our algorithm more robust to non-linear deformation between fingerprint images; use of a simpler alignment method in our algorithm. Experiments using the Fingerprint Verification Competition 2000 (FVC2000) databases with the FVC2000 performance evaluation show that these ideas are effective.