ppxscal/embedding_network huggingface dataset:
Performance Analysis of a Preemptive and Priority Reservation Handoff Scheme for Integrated Service-Based Wireless Mobile Networks
Authors: Jingao Wang, Qing-An Zeng, Dharma P. Agrawal
Venue: IEEE Transactions on Mobile Computing (2003)

In this paper, we propose an analytical model for integrated real-time and non-real-time service in a wireless mobile network with priority reservation and preemptive priority handoff schemes. We categorize the service calls into four different types, namely, real-time and non-real-time service originating calls, and real-time and non real-time handoff service request calls. Accordingly, the channels in each cell are divided into three parts: one is for real-time service calls only, the second is for non-real-time service calls only, and the last one is for overflow of handoff requests that cannot be served in the first two parts. In the third group, several channels are reserved exclusively for real-time service handoffs so that higher priority can be given to them. In addition, a real-time service handoff request has the right to preempt non-real-time service in the preemptive priority handoff scheme if no free channels are available, while the interrupted non-real-time service call returns to its handoff request queue. The system is modeled using a multidimensional Markov chain and a numerical analysis is presented to estimate blocking probabilities of originating calls, forced termination probability, and average transmission delay. This scheme is also simulated under different call holding time and cell dwell time distributions. It is observed that the simulation results closely match the analytical model. Our scheme significantly reduces the forced termination probability of real-time service calls. The probability of packet loss of non-real-time transmission is shown to be negligibly small, as a non-real-time service handoff request in waiting can be transferred from the queue of the current base station to another one.
Dynamic Scheduling of a Two-Class Queue with Setups
Authors: Martin I. Reiman, Lawrence M. Wein
Venue: Operations Research (1998)

We analyze two scheduling problems for a queueing system with a single server and two customer classes. Each class has its own renewal arrival process, general service time distribution, and holding cost rate. In the first problem, a setup cost is incurred when the server switches from one class to the other, and the objective is to minimize the long-run expected average cost of holding customers and incurring setups. The setup cost is replaced by a setup time in the second problem, where the objective is to minimize the average holding cost. By assuming that a recently derived heavy traffic principle holds not only for the exhaustive policy but for nonexhaustive policies, we approximate (under standard heavy traffic conditions) the dynamic scheduling problems by diffusion control problems. The diffusion control problem for the setup cost problem is solved exactly, and asymptotics are used to analyze the corresponding setup time problem. Computational results show that the proposed scheduling policies are within several percent of optimal over a broad range of problem parameters.
Inverting back the inversion of control or, continuations versus page-centric programming
Authors: Christian Queinnec
Venue: ACM SIGPLAN Notices (2003)

Our thesis is that programming web applications with continuations is superior to the current page-centric technology. A continuation is a program-level manageable value representing the rest of the computation of the program. "What to do next" is precisely what has to be explicitly encoded in order to program non trivial web interactions. Continuations allow web applications to be written in direct style that is, as a single program that displays forms and reads form submission since continuations automatically capture everything (control point, lexical bindings, etc.) that is needed to resume the computation. Programming is therefore safer, easier and more re-usable.
On ratio asymptotics for general polynomials
Authors: Ying Guang Shi
Venue: Journal of Approximation Theory (2003)

In this paper some characterizations of the ratio asymptotics for general polynomials are given. These results are extensions and improvements of the ratio asymptotics for orthogonal polynomials and are applicable to the ratio asymptotics for polynomials with disturbed nodes.
A small college response to the mathematics recommendations of curriculum 2001
Authors: Blayne Carroll, Kris Powers
Venue: Journal of Computing Sciences in Colleges (2002)

Recent curricula recommendations by the ACM/IEEE Curriculum 2001 [3] have focused new attention to the role of mathematics in computer science programs. The challenge presented to small colleges is to address these recommendations while working with the limited resources typical of our institutions. In this paper we describe recent efforts to update our mathematics requirements for our computer science major and the ripple effect that lead to changes both in our discrete mathematics course offerings and in the course requirements for our mathematical and computational degree programs.
Black box checking
Authors: Doron Peled, Moshe Y. Vardi, Mihalis Yannakakis
Venue: Journal of Automata, Languages and Combinatorics (2001)

Two main approaches are used for increasing the quality of systems: in model checking , one checks properties of a known design of a system; in testing, one usually checks whether a given implementation, whose internal structure is often unknown, conforms with an abstract design. We are interested in the combination of these techniques. Namely, we would like to be able to test whether an implementation with unknown structure satisfies some given properties. We propose and formalize this problem of black box checking and suggest several algorithms. Since the input to black box checking is not given initially, as is the case in the classical model of computation, but is learned through experiments, we propose a computational model based on games with incomplete information. We use this model to analyze the complexity of the problem. We also address the more practical question of finding an approach that can detect errors in the implementation before completing an exhaustive search.
Multiairport Ground Holding Problem: a Computational Evaluation of Exact Algorithms
Authors: Giovanni Andreatta, Lorenzo Brunetta
Venue: Operations Research (1998)

Congestion in the air traffic network is becoming an increasingly serious problem that causes inconvenience to passengers, losses to airlines and, last but not least, threats to airspace safety. One way of reducing the amount of congestion is to use Ground Holding policies, i.e., to impose on selected aircraft a ground holding prior to their departure so that congestion during peak periods of time may be smoothed away. In this paper we restrict our attention to the Multiairport Ground Holding problem, where congestion may arise only at the airports due to limited arrival capacity. There are a few algorithms that, under suitable hypotheses, find an "optimal" policy for the Multiairport Ground Holding problem. In this paper we evaluate and compare comput ationally three of them, namely, the one recently proposed by Vranas, Bertsimas and Odoni, the one suggested by Andreatta and Tidona and that due to Bertsimas and Stock. The computational evaluation is based on two sets of test problems. The first set consists of seven problems taken from the literature. The second set consists of 32 "realistic" test problems. The results indicate the superiority of the Bertsimas and Stock approach among the three models considered.
A Fast Scaling Algorithm for Minimizing Separable Convex Functions Subject to Chain Constraints
Authors: Ravindra K. Ahuja, James B. Orlin
Venue: Operations Research (2001)

We consider the problem of minimizing ? j?NC j(x j), subject to the following chain constraints x 1 =x 2 = x 3 = Â·Â·Â· = x n, where C j(x j) is a convex function of x j for each j ? N={1,2, ... ,n}. This problem is a generalization of theisotonic regression problems with complete order, an important class of problems in regression analysis that has been examined extensively in the literature. We refer to this problem as thegeneralized isotonic regression problem. In this paper, we focus on developing a fast-scaling algorithm to obtain an integer solution of the generalized isotonic regression problem. LetU denote the difference between an upper bound on an optimal value of x n and a lower bound on an optimal value of x 1. Under the assumption that the evaluation of any function C j (x j) takesO(1) time, we show that the generalized isotonic regression problem can be solved inO(n logU) time. This improves by a factor of n the previous best running time ofO(n 2 logU) to solve the same problem. In addition, when our algorithm is specialized to theisotonic median regression problem (where C j(x j)=c j|x j-a jI) for specified values ofc js anda js, the algorithm obtains a real-valued optimal solution inO(n logn) time. This time bound matches the best available time bound to solve the isotonic median regression problem, but our algorithm uses simpler data structures and may be easier to implement.
Self-stabilization with path algebra
Authors: Bertrand Ducourthial, Sébastien Tixeuil
Venue: Theoretical Computer Science (2003)

Self-stabilizing protocols can resist transient failures and guarantee system recovery in a finite time. We highlight the connexion between the formalism of self-stabilizing distributed systems and the formalism of generalized path algebra and asynchronous iterations with delay. We use the later to prove that a local condition on locally executed algorithm (being a strictly idempotent r-operator) ensures self-stabilization of the global system. As a result, a parametrized distributed algorithm applicable to any directed graph topology is proposed, and the function parameter of our algorithm is instantiated to produce distributed algorithms for both fundamental and high-level applications. Due to fault resilience properties of our algorithm, the resulting protocols are self-stabilizing at no additional cost.
Efficient finite element analysis using mesh superposition technique
Authors: Jin Woo Park, Jae Woong Hwang, Yong Hyup Kim
Venue: Finite Elements in Analysis and Design (2003)

A mesh superposition technique is presented for an efficient finite element analysis. The formulation of the method is given for both single-field assumed displacement finite element models and two-field assumed strain finite element models. Refined local mesh is superimposed on global mesh for the region of interest. It is an adaptive mesh refinement method, which allows local refinement of the mesh without introducing transition region or multi-point constraints. By applying appropriate boundary conditions on the local superimposed mesh, singularity in the global stiffness matrix can be avoided and inter-element compatibility conditions can be satisfied. Effectiveness of the present technique is demonstrated by means of numerical examples of linear static, dynamic and buckling problems of elasticity. Moreover, effectiveness of the present procedure is tested for problems with curved geometries and with distorted grids. Also, various solutions schemes are investigated for effective analysis using the present method.
Performance Bounds and Pathwise Stability for Generalized Vacation and Polling Systems
Authors: Eitan Altman, Serguei Foss, Eric Riehl, Shaler Stidham,  Jr.
Venue: Operations Research (1998)

We consider a generalized vacation or polling system, modeled as an input-output process operating over successive "cycles," in which the service mechanism can be in an "up" mode (processing) or "down" mode (e.g., vacation, walking). Our primary motivation is polling systems, in which there are several queues and the server moves cyclically between them providing some service in each. Our basic assumption is that the amount of work that leaves the system in a "cycle" is no less than the amount present at the beginning of the cycle. This includes the standard gated and exhaustive policies for polling systems in which a cycle begins whenever the server arrives at some prespecified queue. The input and output processes satisfy model-dependent conditions: pathwise bounds on the average rate and the burstiness (Cruz bounds); existence of long-run average rates; a pathwise generalized Law of the Iterated Logarithm; or exponentially or polynomially bounded tail probabilities of burstiness. In each model we show that these properties are inherited by performance measures such as the workload and output processes, and that the system is stable (in a model-dependent sense) if the input rate is smaller than the up-mode processing rate.
Maximizing handler thermal throughput with a rib-roughened test tray
Authors: Andreas C. Pfahnl, John H. Lienhard V., Alexander H. Slocum
Venue: Proceedings of the 1998 IEEE International Test Conference (1998)

A new design feature of an integrated circuit (IC) testhandler tray is described that significantly improves theconvective heat transfer to the tray and the IC devices inthe tray. The improved tray incorporates verticallyprotruding ribs which breakup thermal boundary layersand enhance mixing. High-speed, tray-based handlers canconsequently warm or cool trays of devices at substantiallyfaster rates. Design equations for the tray ribs are verifiedthrough experimental testing and provide a means topredict the warm-up or cool-down times of the tray anddevices.
Statements of core values and corporate codes of ethics for IT related firms
Authors: James Harris, Maeve Cummings, Christine Fogliasso
Venue: Journal of Computing Sciences in Colleges (2002)

The ethical use of information technology is an increasing concern for all organizations. This is especially true for information technology organizations. In this paper we review a simple model of the ethical decision making process with emphasis on the role that statements of core values and corporate codes of ethics can fulfill in helping create an ethical decision making environment within an organization. We review the web sites of fifty Information technology firms to observe the extent to which corporate web sites are used to communicate the code of ethics. Also, the components of the statements of core values for eleven IT firms are discussed and an overview of the corporate codes of ethics for five IT firms is provided.
Long-term stability of variable stepsize approximations of semigroups
Authors: Nikolai Bakaev, Alexander Ostermann
Venue: Mathematics of Computation (2002)

This paper is concerned with the stability of rational one-step approximations of C0 semigroups. Particular emphasis is laid on long-term stability bounds. The analysis is based on a general Banach space framework and allows variable stepsize sequences. Under reasonable assumptions on the stepsize sequence, asymptotic stability bounds for general Co semigroups are derived. The bounds are typical in the sense that they contain, in general, a factor that grows with the number of steps. Under additional hypotheses on the approximation, more favorable stability bounds are obtained for the subclass of holomorphic semigroups.
A Web-Based Peer-to-Peer Architecture for Collaborative Nomadic Working
Authors: Gerald Reif, Engin Kirda, Harald Gall, Pascal Fenkam, Gian Pietro Picco, Gianpaolo Cugola
Venue: Proceedings of the 10th IEEE International Workshops on Enabling Technologies: Infrastructure for Collaborative Enterprises (2001)

With the recent advances in mobile computing, distributed organizations are facing a growing need for advanced Information and Communication Technologies (ICT) that support mobile working. The ability to use information effectively anywhere and anytime has become a key business success factor. Although many Computer Supported Collaborative Work (CSCW) systems have been introduced to date, technologies and architectures that support the collaboration of nomadic workers on a wide range of mobile devices, notebooks and personal computers is still a challenge. The MObile Teamwork Infrastructure for Organizations Networking (MOTION)1 project is aiming to design a highly flexible, open and scalable ICT architecture for mobile collaboration. In this paper, we present the mobile collaboration requirements of two MOTION industry case studies, and highlight the advantages of a Web-based peer-to-peer architecture and for nomadic working.
Agility---: the key to survival of the fittest in the software market
Authors: Julie Smith David, William E. McCarthy, Brian S. Sommer
Venue: Communications of the ACM (2003)

The ideas of Darwinian evolution can illuminate the niches in which systems can flourish in today's tumultuous IT environment---and help identify the inevitable evolutionary changes.
Complexity of Memory-Efficient Kronecker Operations with Applications to the Solution of Markov Models
Authors: Peter Buchholz, Gianfranco Ciardo, Susanna Donatelli, Peter Kemper
Venue: INFORMS Journal on Computing (2000)

We present new algorithms for the solution of large structured Markov models whose infinitesimal generator can be expressed as a Kronecker expression of sparse matrices. We then compare them with the shuffle-based method commonly used in this context and show how our new algorithms can be advantageous in dealing with very sparse matrices and in supporting both Jacobi-style and Gauss-Seidel-style methods with appropriate multiplication algorithms. Our main contribution is to show how solution algorithms based on Kronecker expression can be modified to consider probability vectors of size equal to the "actual" state space instead of the "potential" state space, thus providing space and time savings. The complexity of our algorithms is compared under different sparsity assumptions. A nontrivial example is studied to illustrate the complexity of the implemented algorithms.
Toward New Metrics for Net-Enhanced Organizations
Authors: Detmar W. Straub, Donna L. Hoffman, Bruce W. Weber, Charles Steinfield
Venue: Information Systems Research (2002)

Metrics aresine qua non for solid research, and scientific metrics have now been advanced with new approaches in the arena of Net-enablement (NE), otherwise known as e-commerce. Questions that likely require additional attention include: (1) Where/what is the real value in substituting information for physical processes?, (2) which NE systems effectively support end-to-end fulfillment?, and (3) when should a Net-enabled organization share information? With respect to extant studies in Net-enhancement, the field has been advanced in three methodological dimensions. Multiple methods have been used to validate measures. Approaches to metrics using archival/secondary data have also been initiated. Finally, strong external validity has been established through large scale data gathering.
Managing static leakage energy in microprocessor functional units
Authors: Steven Dropsho, Volkan Kursun, David H. Albonesi, Sandhya Dwarkadas, Eby G. Friedman
Venue: Proceedings of the 35th annual ACM/IEEE international symposium on Microarchitecture (2002)

Static energy due to subthreshold leakage current is projected to become a major component of the total energy in high performance microprocessors. Many studies so far have examined and proposed techniques to reduce leakage in on-chip storage structures. In this study, static energy is reduced in the integer functional units by leveraging the unique qualities of dual threshold voltage domino logic.Domino logic has desirable properties that greatly reduce leakage current while providing fast propagation times. However, due to the energy cost of entering the low leakage current state (sleep mode), domino logic has thus far been used only for leakage reduction in the longterm standby mode. We examine the utility of the sleep mode (while considering the aforementioned costs) when idle times are relatively short, one to a few hundred cycles, as is often the case for functional units.Using an analytical energy model suitable for architecture-level analysis, we explore the interaction of the application and technology, and the effect on energy and performance as the underlying parameters are varied, on a set of benchmarks. Our results show that if the leakage approaches the magnitude as projected in the literature, even for short idle intervals as few as ten cycles, an aggressive policy of activating the sleep mode at every idle period performs well and a more complex control strategy may not be warranted. We also propose a simple design, called Gradual Sleep, to reduce the energy impact of using the sleep mode for smaller idle periods.
An efficient algorithm for enumeration of triangulations
Authors: Sergei Bespamyatnikh
Venue: Computational Geometry: Theory and Applications (2002)

We consider the problem of enumerating triangulations of n points in the plane in general position. We introduce a tree of triangulations and present an algorithm for enumerating triangulations in O(loglog n) time per triangulation. It improves the previous bound by almost linear factor.
Hop-by-hop routing algorithms for premium traffic
Authors: Jun Wang, Klara Nahrstedt
Venue: ACM SIGCOMM Computer Communication Review (2002)

In Differentiated Service (DiffServ) networks, the routing algorithms used by the premium class traffic, due to the high priority afforded to that traffic, may have a significant impact not only on the premium class traffic itself, but on all other classes of traffic as well. The shortest hop-count routing scheme, used in current Internet, turns out to be no longer sufficient in DiffServ networks. This paper studies the problem of finding optimal routes for the premium-class traffic in a DiffServ domain, such that (1) no forwarding loop exists in the entire network in the context of hop-by-hop routing; and (2) the residual bandwidth on bottleneck links is maximized. This problem is called the Optimal Premium-class Routing (OPR) problem. We prove in this paper that the OPR problem is NP-hard.To handle the OPR problem, first, we analyze the strength and weaknesses of two existing algorithms (Widest-Shortest-Path algorithm and Bandwidth-inversion Shortest-Path algorithm). Second, we propose a novel heuristic algorithm, called the Enhanced Bandwidth-inversion Shortest-Path (EBSP) algorithm. We prove theoretically the correctness of the EBSP algorithm, i.e., we show that it is consistent and loop-free. Our extensive simulations in different network environments show clearly that the EBSP algorithm performs better when routing the premium traffic in complex, heterogeneous networks.
From Revenue Management Concepts to Software Systems
Authors: Nicola Secomandi, Kirk Abbott, Tankut Atan, E. Andrew Boyd
Venue: Interfaces (2002)

In 1999, after developing and installing over 170 revenue management (RM) systems for more than 70 airlines, PROS Revenue Management, Inc. had the opportunity to develop RM systems for three companies in nonairline industries. PROS research and design department designed the opportunity analysis study (OAS), a mix of OR/MS, consulting, and software development practices to determine the applicability of RM in new business situations. PROS executed OASs with the three companies. In all three cases, the OAS supported the value of RM and led to contracts for implementation of RM systems.