ppxscal/embedding_network huggingface dataset:
Efficient execution of pure object-oriented programs by follow-up compilation
Authors: S. Baskiyar
Venue: Computing (2002)

Dynamic type checking and method binding slows pure object-oriented programs such as those written in Smalltalk. Dynamic method lookup is needed to support method overriding and type-method conformance. We have developed a platform independent technique that implements method overriding efficiently for pure object-oriented languages. The technique involves binding non-overridden method calls at compile time. The overridden method calls are also resolved (and bound) statically using simple inferences. Overridden method bindings are corrected dynamically using an Overridden Method Dictionary. Using simulations, we demonstrate that this technique offers 35%-70% reduction in the average method lookup delay over the Berkeley Smalltalk implementation. This technique has very low compile time overhead, memory overhead, does not need specialized hardware and allows shared code pages in concurrent programs. For programs which may be re-used, it is proper to have a follow-up compilation to generate efficient code after the program development is complete.
On the asymmetry of random regular graphs and random graphs
Authors: Jeong Han Kim, Benny Sudakov, Van H. Vu
Venue: Random Structures Algorithms (2002)

This paper studies the symmetry of random regular graphs and random graphs. Our main result shows that for all 3 ≤ d ≤ n - 4 the random d-regular graph on n vertices almost surely has no nontrivial automorphisms. This answers an open question of N. Wormald [13].
Head tracking using shapes and adaptive color histograms
Authors: Qingshan Liu, Songde Ma, Hanqing Lu
Venue: Journal of Computer Science and Technology (2002)

A new method is presented for tracking a person's head in real-time. The head is shaped as an ellipse, and the adaptively modified RGB color histogram is used to represent the tacked object (head). The method is composed of two parts. First, a robust nonparametrlc technique, called mean shift algorithm, is adopted for histogram matching to estimate the head's location in the current frame. Second, a local search is performed after histogram matching to maximize the normalized gradient magnitude around the boundary of the elliptical head, so that a more accurate location and the best scale size of the head can be obtained. The method is demonstrated to be a real-time tracker and robust to clutter, scale variation, occlusion, rotation and camera motion, for several test sequences.
Replacing Copies with Connections: Managing Software across the Virtual Organization
Authors: Tobias Murer, Michael L. Van De Vanter
Venue: Proceedings of the 8th Workshop on Enabling Technologies on Infrastructure for Collaborative Enterprises (1999)

The Internet, the World Wide Web, Java TM technology, and software components are changing the software business. Activities traditionally constrained by the need for intense information management increasingly involve cooperating organizations. Information management tools and techniques do not scale well in the face of this organizational complexity. Informal sharing, based largely on manual copying of information, cannot meet the demands of the task as size and complexity increase. Formal approaches to sharing information are based on groupware tools, but cooperating organizations do not always enjoy the trust or commonality of sophisticated infrastructure, methods, and skills that this approach requires. The application web is a simple, loosely coupled, highly flexible strategy for information sharing that bridges the gap. Extensive information relevant to different parts of the software life cycle is interconnected in a simple, easily described way; such connections permit selective information sharing by a variety of tools and in a variety of collaboration modes that vary in the amount of organizational coupling they require.
User recalled occurrences of usability errors: implications on the user experience
Authors: Helena Mentis, Geri Gay
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

Usability testing determines what problems thwart goal attainment, but what problems shape the user experience? This study gathered users recalled instances of frustration from using various technologies and categorized those frustrating incidents with the User Action Framework, an adaptation of Norman's seven stages of action for classifying usability problems. We found that many of the recalled frustrating incidents occurred while the user was in the Outcome phase and that most of those incidents were intrusive in the user's cognitive flow.
FantasyA and SenToy
Authors: Kristina Höök, Adrian Bullock, Ana Paiva, Marco Vala, Ricardo Chaves, Rui Prada
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

FantasyA is a role-playing game where emotions are part of the game logic. SenToy is a tangible interface device [2], used to influence emotional behaviour in FantasyA. Players in the game FantasyA have to master SenToy and exhibit a particular set of emotions and perform a set of actions in order to evolve in the game [3]. A study was undertaken to gauge the success of the overall gaming experience, as well as the individual components, the FantasyA game with its emotional content and the SenToy control device with its gestural input.
Sensitivity Analysis for Stochastic User Equilibrium Network Flows-- A Dual Approach
Authors: Jiang Qian Ying, Toshihiko Miyagi
Venue: Transportation Science (2001)

Recently, extensive studies have been conducted on the computational methods of sensitivity analysis for the Wardropian equilibrium modeling of traffic networks and their applications. But the same problems in the context of the stochastic user equilibrium modeling seem not to have been addressed. In this paper, we present a method for sensitivity analysis for network flows at stochastic user equilibrium. Our method is developed from a dual formulation of the stochastic user equilibrium analysis. By adopting Dial's algorithm for stochastic traffic assignment, we are able to formulate a computationally efficient link-based algorithm for the sensitivity analysis. Since the Wardropian equilibrium in a traffic network is an extreme case of stochastic user equilibrium with ? ? 8, ? being a dispersion parameter in the expected utility function for stochastic route choice, the method presented here can also be used for sensitivity analysis of the Wardropian equilibrium by setting ? large enough.
Simple general recursion in type theory
Authors: Ana Bove
Venue: Nordic Journal of Computing (2001)

General recursive algorithms are such that the recursive calls are performed on arguments satisfying no condition that guarantees termination. Hence, there is no direct way of formalising them in type theory.The standard way of handling general recursion in type theory uses a well-founded recursion principle. Unfortunately, this way of formalising general recursive algorithms often produces unnecessarily long and complicated codes. On the other hand, functional programming languages like Haskell impose no restrictions on recursive programs, and then writing general recursive algorithms is straightforward. In addition, functional programs are usually short and self-explanatory. However, the existing frameworks for reasoning about the correctness of Haskell-like programs are weaker than the framework provided by type theory.The goal of this work is to present a method that combines the advantages of both programming styles when writing simple general recursive algorithms. The method introduced here separates the computational and logical parts of the definition of an algorithm, which has several advantages. First, the resulting type-theoretic algorithms are compact and easy to understand; they are as simple as their Haskell versions. Second, totality is now a separate task and hence, this method can also be used in the formalisation of partial functions. Third, the method presented here also simplifies the task of formal verification. Finally, it can easily be extended to treat nested and mutual recursion.The main feature of the method is the introduction of an inductive predicate, specially defined for the algorithm to be formalised. This predicate can be thought of as characterising the set of inputs for which the algorithm terminates. It contains an introduction rule for each of the cases that need to be considered and provides an easy syntactic condition that guarantees the termination of the algorithm.
From linear to nonlinear iterative methods
Authors: M. N. Vrahatis, G. D. Magoulas, V. P. Plagianakos
Venue: Applied Numerical Mathematics (2003)

This paper constitutes an effort towards the generalization of the most common classical iterative methods used for the solution of linear systems (like Gauss-Seidel, SOR, Jacobi, and others) to the solution of systems of nonlinear algebraic and/or transcendental equations, as well as to unconstrained optimization of nonlinear functions. Convergence and experimental results are presented. The proposed algorithms have also been implemented and tested on classical test problems and on real-life artificial neural network applications and the results to date appear to be very promising.
Bisimulation equivalences for graph grammars
Authors: Paolo Baldan, Andrea Corradini, Ugo Montanari
Venue: Formal and natural computing (2002)

Along the years the concurrent behaviour of graph grammars has been widely investigated, and, in particular, several classical approaches to the semantics of Petri nets have been extended to graph grammars. Most of the existing semantics for graph grammars provide a (possibly concurrent) operational model of computation, while little interest has been devoted to the definition of abstract observational semantics. The aim of this paper is to introduce and study a behavioural equivalence over graph grammars, inspired by the classical history preserving bisimulation. Several choices are conceivable according to the kind of concurrent observation one is interested in. We concentrate on the basic case where the concurrent nature of a graph grammar computation is described by means of a prime event structure. As it happens for Petri nets, history preserving bisimulation can be studied in the general framework of causal automata -- a variation of ordinary automata introduced to deal with history dependent formalisms. In particular, we prove that history preserving bisimulation is decidable for finite-state graph grammars, by showing how the problem can be reduced to deciding the equivalence of finite causal automata.
Scheduling with Finite Capacity Output Buffers
Authors: Nicholas G. Hall, Marc E. Posner, Chris N. Potts
Venue: Operations Research (1998)

In many scheduling problems, a job that completes processing may need to be held in an output buffer until the customer is ready to accept delivery. Buffer capacity is usually assumed to be infinite. We study a number of the best known single machine scheduling problems, under several alternative assumptions about the capacity of the output buffer. Specifically, we allow the buffer capacity to be either zero, fixed, or specified as part of problem input. We also consider situations in which all jobs have the same storage requirement in the buffer, and others where the storage requirement may vary. Further, we consider generalizations where there is a time interval within which a customer accepts delivery without cost to the producer. A classification scheme for these problems is provided. For each problem considered, we provide either an efficient algorithm or a proof that such an algorithm is unlikely to exist. Our results provide a mapping of the computational complexity of these problems which parallels those that are available for classical scheduling problems with infinite buffer capacity.
Investigating the relationship between strategic alignment and IT business value: the discovery of a paradox
Authors: Paul P. Tallon, Kenneth L. Kraemer
Venue: Creating business value with information technology: challenges and solutions (2003)

Although business executives remain skeptical about the extent of payoffs from investment in information technology (IT), strategic alignment or the alignment of information systems strategy with business strategy continues to be ranked as one of the most important issues facing corporations. In this paper, we report on the results of a process-level study to investigate the relationship between strategic alignment and IT payoffs. An analysis of survey data from 63 firms finds a positive and significant relationship between strategic alignment and IT payoffs, a relationship that holds for all firms, irrespective of their strategic intent or goals for IT. However, in exploring minor differences in strategic alignment between firms with different goals for IT, we uncovered evidence of an alignment paradox. This paradox shows that while strategic alignment can lead to increased payoffs from IT, this relationship is only valid up to a certainpoint beyond which, paradoxically, further increases in strategic alignment appear to lead to lower IT payoffs. Finally, we offer some suggestions for why this paradox might exist, specifically around issues of environmental uncertainty, industry clock-speed, and the need for organizational flexibility.
Information and Inventory Recourse for a Two-Market, Price-Setting Retailer
Authors: Nicholas C. Petruzzi, Maqbool Dada
Venue: Manufacturing Service Operations Management (2001)

We analyze the problem of determining inventory and pricing decisions in a two-period retail setting when an opportunity to refine information about uncertain demand is available. The model extends the newsvendor problem with pricing by allowing for multiple suppliers, the pooling of procurement resources, and more general informational dynamics. One contribution is the solution procedure: We show that all decisions (up to 7 in all, including recourse decisions) can be determined uniquely as a function of a surrogate first-period decision called the stocking factor. Hence, the two-period decision problem with recourse reduces to a search for one decision variable. A second contribution is the policy implications: We find that the cost of learning is (1) a consequence of censored information because, on the margin, learning is free if full information is guaranteed; (2) measured in the form of an increased stocking factor; and (3) shared with the consumer in the form of a higher selling price when demand uncertainty is additive. A third contribution is the application of the results to three motivating examples: a market research problem in which a product is introduced in a test market prior to a widespread launch; a global newsvendor problem in which a seasonal product is sold in two different countries with nonoverlapping selling seasons; and a minimum-quantity commitment problem in which procurement resources for multiple purchases may be pooled.
Sendmail, Third Edition, 3 edition
Authors: Bryan Costales, Eric Allman
Venue:  (2002)

:Reliable, flexible, and configurable enough to solve the mail routing needs of any site, sendmail has withstood the test of time, but has become no less daunting in its complexity. Even the most experienced system administrators have found it challenging to configure and difficult to understand. For help in unraveling its intricacies, sendmail administrators have turned unanimously to one reliable source -- the bat book -- or sendmail, by Bryan Costales and sendmail author Eric Allman. Now in its third edition, this bestselling reference will help you master the most demanding version of sendmail yet. The new edition of sendmail has been completely revised to cover sendmail 8.12 -- a version with more features and fundamental changes than any previous version of the Unix-based email routing program. Because the latest version of sendmail differs so significantly from earlier versions, a massive rewrite of this bestselling reference was called for. The book begins by guiding you through the building and installation of sendmail and its companion programs, such as vacation and makemap. These additional programs are pivotal to sendmail's daily operation. Next, we cover the day-to-day administration of sendmail. This section includes two entirely new chapters -- "Performance Tuning," to help you make mail delivery as efficient as possible, and "Handling Spam," to deal with sendmail's rich anti-spam features. The next section of the book tackles the sendmail configuration file and debugging. And finally, the book wraps up with five appendixes that provide more detail about sendmail than you may ever need. Altogether, versions 8.10 through 8.12 include dozens of new features, options, and macros, and this greatly expanded edition thoroughly addresses each. With sendmail, Third Edition, in hand, you will be able to configure this challenging but necessary utility for whatever your system requires. This much anticipated revision is essential reading for sendmail administrators.
Asymptotic distribution of negative eigenvalues for three dimensional Pauli operators with nonconstant magnetic fields
Authors: Akihiro Shimomura
Venue: Publications of the Research Institute for Mathematical Sciences (2002)

We study the asymptotic distribution of negative eigenvalues of three dimensional Pauli operators with a two dimensional magnetic field and a three dimensional potential which decay to zero at infinity. For λ > 0 sufficiently small, we estimate the number of eigenvalues less than -λ of such Pauli operators.
Formal methods in practice: the missing links. a perspective from the security area
Authors: Dominique Bolignano, Daniel Le Métayer, Claire Loiseaux
Venue: Modeling and verification of parallel processes (2001)

Our goal in this paper is not to enrich the literature with yet another defence of formal methods, but rather to build on our experience of using and studying formal methods in security to provide an industrial point of view, with a strong emphasis on practicality. We also hope that, even if we take our inspiration mainly in the security area, most of our observations on formal methods are relevant to other application domains as well. The term "security" itself can be used in various contexts with different meanings. We use it here in the sense of security of information, as defined by the standard triptych: confidentiality, integrity and availability.
Analysis of K-Transmit Dual-Receive Diversity withCochannel Interferers over a Rayleigh Fading Channel
Authors: Parag A. Dighe, Ranjan K. Mallik, Sudhanshu S. Jamuar
Venue: Wireless Personal Communications: An International Journal (2003)

The need to combat the severe effects of fading and interference in the rapidly increasing number of communication systems providing wireless services has motivated the study of diversity in the presence of interference. Hence the analysis of wireless systems with both transmit and receive diversity and subject to cochannel interference is an important tool for system design. We consider here a K-transmit dual-receive diversity communication system employing K antennas for transmission and two antennas for reception. The desired signal is corrupted by N interfering sources apart from additive white Gaussian noise. The channel is Rayleigh fading. As a result, the channel matrix for the desired signal and the propagation vectors of the interferers have zero-mean complex Gaussian entries; the entries are assumed to be independent and identically distributed. The complex receive weight vector used for combining the received signals is chosen so as to maximize the output signal-to-interference-plus-noise ratio (SINR). From the statistics of the channel matrix and the propagation vectors of the interferers, we derive a closed-form expression for the probability density function (p.d.f.) of the maximum output SINR. This p.d.f. can be used to obtain the symbol error probability for different digital modulation schemes.
Case study of a patient data management system: a complex implementation in an intensive care unit
Authors: Nathalie Mitev, Sharon Kerkham
Venue: Advanced topics in end user computing (2002)

Since the National Health Service reforms were introduced, the NHS has moved towards a greater emphasis on accountability and efficiency of healthcare. These changes rely on the swift delivery of IT systems, implemented into the NHS because of the urgency to collect data to support these measures. The case study details the events surrounding the introduction of a patient data management system into an intensive care unit in a UK hospital. It shows that its implementation was complex and involved organizational issues related to the costing of healthcare, legal and purchasing requirements, systems integration, training and staff expertise, and relationships with suppliers. It is suggested that the NHS is providing an R&D environment which others are benefiting from. The NHS is supporting software development activities that are not recognized, and the true costs of this task are difficult to estimate. It is also argued that introducing PDMS crystallizes many different expectations making them unmanageably complex. This could also be due to PDMS being a higher order innovation that attempts to integrate information systems products and services with the core business.
A quantitative framework for automated pre-execution thread selection
Authors: Amir Roth, Gurindar S. Sohi
Venue: Proceedings of the 35th annual ACM/IEEE international symposium on Microarchitecture (2002)

Pre-execution attacks cache misses for which address prediction driven prefetching fails. In pre-execution, copies of cache miss computations are isolated from the main program and launched as separate threads called p-threads whenever the processor anticipates an upcoming miss. P-thread selection is the task of deciding what computations should execute as p-threads and when they should be launched such that total execution time is minimized. It is central to the success of pre-execution.We introduce a framework for automated static p-thread selection, a static p-thread being one whose dynamic instances are repeatedly launched during course of program execution. Our approach is to formalize the problem quantitatively and then apply standard techniques to solve it analytically. The framework has two novel components. The slice tree is a data structure that compactly represents a set of static p-threads and the relationships among them. Aggregate advantage is a formula that uses raw program statistics and computation structure to assign each candidate static p-thread a numeric score based on estimated latency tolerance and overhead aggregated over its expected dynamic executions.We use the framework to select p-threads that cover L2 misses and study its effectiveness under different conditions via detailed simulation. We measure the effect of constraining p-thread length, locally optimizing p-threads, using different program samples as a statistical basis selection, and varying several machine parameters. Our framework responds to these changes in an intuitive way. We also validate that aggregate advantage correctly models actual pre-execution.