ppxscal/embedding_network huggingface dataset:
The ecology of mobile commerce: charting a course for success using value chain analysis
Authors: Andreas Rülke, Anand Iyer, Greg Chiasson
Venue: Mobile commerce: technology, theory, and applications (2003)

The convergence of the Internet with wireless telecommunications has profound and pressing implications for enterprises ranging from long-distance carriers to record labels to automakers. The fast-growing ability of wireless devices to handle a wealth of data content as well as voice transmission is opening the door to the creation of new products, services, markets, and revenue streams. But in what prevailing form will mobile commerce--the still-nascent effort to assemble and monetize the wireless Internet--emerge? How will the vast potential variety of data-based content be created, aggregated, and profitably delivered to both individual and business customers? The essential tool for approaching these still-open questions is value chain analysis, A value chain is a map of the entire set of competencies, investments, and activities required to produce, deliver, maintain, and reap the proceeds from a product or service. The profits and competitive advantages of participation in a given value chain reside dynamically within the chain, pooling at the positions of greatest value. (The returns to the different forms of participation in a value chain, particularly one as complex as mobile commerce, are anything but equal.) This chapter presents and analyzes an extended model of the unfolding m-commerce value chain. The goal is to provide an effective tool for planning and executing relevant business decisions in the face of such complicating factors as technology migration, the absence of market data, and inescapable constraints on organizational resources. The analysis and recommendations are supported by data from a survey with wide participation conducted by the authors.
Eliminating Exception Constraints of Java Programs for IA-64
Authors: Kazuaki Ishizaki, Tatsushi Inagaki, Hideaki Komatsu, Toshio Nakatani
Venue: Proceedings of the 2002 International Conference on Parallel Architectures and Compilation Techniques (2002)

Java exception checks are designed to ensure that any faulting instruction causing a hardware exception does not terminate the program abnormally. These checks, however, impose some constraints upon the execution order between an instruction potentially raising a Java exception and a faulting instruction causing a hardware exception. This reduces theeffectiveness of instruction reordering optimization. We propose a new framework to effectively perform speculation for the Java language using a direct acyclic graph representation based on the SSA form. Using this framework, we apply a well-known speculation technique to a faulting load instruction to eliminate such constraints. We use edges to represent exception constraints. This allows us to accurately estimate the potential reduction of the critical path length for applying speculation. We also propose an approach to avoid extra copy instructions and to generate efficient code with minimum register pressure. We have implemented the technique in the IBM Java Just-In-Time compiler, and observed performance improvements up to 25% for micro-benchmark programs, up to 10% for Java Grande Benchmark Suite, and up to 12% for SPECjvm98 on an Itanium processor.
The scaling hypothesis: simplifying the prediction of network performance using scaled-down simulations
Authors: Konstantinos Psounis, Rong Pan, Balaji Prabhakar, Damon Wischik
Venue: ACM SIGCOMM Computer Communication Review (2003)

As the Internet grows, so do the complexity and computational requirements of network simulations. This leads either to unrealistic, or to prohibitely expensive simulation experiments.We explore a way to side-step this problem, by combining simulation with sampling and analysis. Our hypothesis is this: if we take a sample of the traffic, and feed it into a suitably scaled version of the system, we can extrapolate from the performance of the scaled system to that of the original.We find that when we scale a network which is shared by TCP-like flows, and which is controlled by a variety of active queue management schemes, then performance measures such as queueing delay and the distribution of flow transfer times are left virtually unchanged. Hence, the computational requirements of network simulations and the cost of experiments can decrease dramatically.
A system for graph-based visualization of the evolution of software
Authors: Christian Collberg, Stephen Kobourov, Jasvir Nagra, Jacob Pitts, Kevin Wampler
Venue: Proceedings of the 2003 ACM symposium on Software visualization (2003)

We describe GEVOL, a system that visualizes the evolution of software using a novel graph drawing technique for visualization of large graphs with a temporal component. GEVOL extracts information about a Java program stored within a CVS version control system and displays it using a temporal graph visualizer. This information can be used by programmers to understand the evolution of a legacy program: Why is the program structured the way it is? Which programmers were responsible for which parts of the program during which time periods? Which parts of the program appear unstable over long periods of time and may need to be rewritten? This type of information will complement that produced by more static tools such as source code browsers, slicers, and static analyzers.
On increasing architecture awareness in program optimizations to bridge the gap between peak and sustained processor performance: matrix-multiply revisited
Authors: David Parello, Olivier Temam, Jean-Marie Verdun
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

As the complexity of processor architectures increases, there is a widening gap between peak processor performance and sustained processor performance so that programs now tend to exploit only a fraction of available performance. While there is a tremendous amount of literature on program optimizations, compiler optimizations lack efficiency because they are plagued by three flaws: (1) they often implicitly use simplified, if not simplistic, models of processor architecture, (2) they usually focus on a single processor component (e.g., cache) and ignore the interactions among multiple components, (3) the most heavily investigated components (e.g., caches) sometimes have only a small impact on overall performance. Through the in-depth analysis of a simple program kernel, we want to show that understanding the complex interactions between programs and the numerous processor architecture components is both feasible and critical to design efficient program optimizations.
Behavioural modelling of long-lived evolution processes: some issues and an example
Authors: M. M. Lehman, G. Kahen J. F. Ramil
Venue: Journal of Software Maintenance: Research and Practice (2002)

For reasons now well understood, application software that is regularly used for real-world problem solving must be continually adapted and enhanced to maintain its fitness to an ever-changing real world, its applications and application domains. This type of activity is termed progressive. As evolution continues, the complexity (functional, structural) of the evolving system is likely to increase unless work, termed antiregressive , is undertaken to control and even reduce it. However, with progressive and anti-regressive work naturally competing for the same pool of resources, management requires means to estimate the amount of work and resources to be applied to each of the two types. After providing a necessary background, the paper describes a systems dynamics model that can serve as the core of a tool to support decision making regarding the optimal personnel allocation over the system lifetime. The model is provided as an example of the use of formalisms in modelling the behaviour of the evolution process.
Evaluating the Impact of Dss, Cognitive Effort, and Incentives on Strategy Selection
Authors: Peter Todd, Izak Benbasat
Venue: Information Systems Research (1999)

Decision support system (DSS) researcher- have long debated whether or not the provision of a DSS would lead to greater decision-making effectiveness, efficiency, or both. The work described in thi- paper examine- how DSS designer- can guide user- toward- employing more normative decision strategies. Working from notion- of restrictiveness and decisional guid- ance (Silver 1990) supplemented by the cost-benefit framework of cognition, we explain how DSS capabilitie- influence decision behavior and performance through the manipulation of effort. The result- of thi- work should assist DSS developer- to devise directed or nondirected approache- to effect desired behaviors.
Design and Evaluation of Data Storage and Retrieval Strategies in a Distributed Memory Continuous Media Server
Authors: Chutimet Srinilta, Divyesh Jadav, Alok N. Choudhary
Venue: Proceedings of the 11th International Symposium on Parallel Processing (1997)

High performance servers and high-speed networks will form the backbone of the infra-structure required for distributed multimedia information systems. Given that the goal of such a server is to support hundreds of interactive data streams simultaneously, various tradeoffs are possible with respect to the storage of data on secondary memory, and its retrieval therefrom. In this paper we identify and evaluate these tradeoffs. We evaluate the effect of varying the stripe factor and also the performance of batched retrieval of disk--resident data. We develop a methodology to predict the stream capacity of such a server. The evaluation is done for both uniform and skewed access patterns. Experimental results on the Intel Paragon computer are presented.
Scheduling with Finite Capacity Input Buffers
Authors: Nicholas G. Hall, Marc E. Posner, Chris N. Potts
Venue: Operations Research (1998)

In many scheduling problems, a newly released job must be stored in an input buffer while it waits to begin processing. The lack of attention given to these buffers in the classical scheduling literature results from the implicit assumption that they have infinite capacity. In modern manufacturing environments, however, there are several important reasons for limiting buffer capacity. We study nonpreemptive single machine dynamic scheduling problems under the assumption that some jobs may be lost, either because of insufficient input buffer capacity, or because due dates cannot be met. The objective is to minimize the weighted or unweighted number of lost jobs. We study problems with zero, fixed or arbitrary buffer capacity, with unit or arbitrary processing times, and with unit or arbitrary buffer storage requirements. We present a complexity classification in which, for each problem, either an efficient algorithm is derived, or a proof is given that such an algorithm is unlikely to exist.
Manufacturability Analysis of Analog CMOS ICs through Examination of Multiple Layout Solutions
Authors: Pedram Khademsameni, Marek Syrzycki
Venue: Proceedings of the 17th IEEE International Symposium on Defect and Fault-Tolerance in VLSI Systems (2002)

This paper introduces a methodology for the manufacturability analysis of analog CMOS ICs. The methodology is based on examination of several layout solutions of a single circuit. Acritical area approach to evaluate a theoretical random-defect limited yield is applied for eachlayout solution. Users can choose the appropriate layout solution after comparing the theoretical yield values and considering results obtained from economical post-layout simulation tools. The theoretical yield has been proposed as one of possible quality factors inthe design for manufacturability. The multi-layout approach, which is presented here, has beenimplemented in a CAD tool (ALDAC). The use of this CAD tool for layout generation and analysis of circuit manufacturability will be presented here.
The MCMC and SML estimation of a self-selection model with two outcomes
Authors: Murat K. Munkin
Venue: Computational Statistics Data Analysis (2003)

A self-selection model with discrete and continuous outcomes and a treatment variable is considered. The treatment variable is endogenous to the two outcome variables. Two estimation procedures are proposed and compared. The first estimation approach is Bayesian and uses the Markov Chain Monte Carlo (MCMC) methods. It constructs stationary Markov chains that converge to the posterior distribution of the parameters of the mode. The second one is a full information maximum likelihood approach, using the simulated maximum likelihood (SML). estimator. Both methods are tested on a numerical example.
Capacity Expansion and Equipment Replacement: a Unified Approach
Authors: Jonathan P. Caulkins, Edward H. Kaplan, Peter Lurie, Thomas O'Connor, Sung-Ho Ahn, Kenneth Chelst, S. Rajagopalan
Venue: Operations Research (1998)

Businesses frequently have to decide which of their existing equipment to replace, taking into account future changes in capacity requirements. The significance of this decision becomes clear when one notes that expenditure on new plant and equipment is a significant proportion of the GDP in the United States. The equipment replacement literature has focused on the replacement issue, usually ignoring aspects such as future demand changes and economies of scale. On the other hand, the capacity expansion literature has focused on the expansion of equipment capacity to meet demand growth, considering economies of scale but ignoring the replacement aspect. This paper attempts to unify the two streams of research by developing a general model that considers replacement of capacity as well as expansion and disposal, together with scale economy effects. Even special cases of the problems discussed here, such as the parallel machine replacement problem, have been considered difficult so far. However, we show that the problem can be solved efficiently by formulating it in a novel, disaggregate manner and using a dual-based solution procedure that exploits the structure of the problem. We also provide computational results to affirm that optimal or near-optimal solutions to large, realistic problems can be determined efficiently. We demonstrate the robustness of this approach by showing how other realistic features such as quantity discounts in purchases, alternative technology types or suppliers, and multiple equipment types can be incorporated.
Techniques for Estimation of Design Diversity for Combinational Logic Circuits
Authors: Subhasish Mitra, Nirmal R. Saxena, Edward J. McCluskey
Venue: Proceedings of the 2001 International Conference on Dependable Systems and Networks (formerly: FTCS) (2001)

Abstract: Design diversity has long been used to protect redundant systems against common-mode failures. The conventional notion of diversity relies on "independent" generation of "different" implementations of the same logic function. This concept is qualitative and does not provide a basis to compare the reliabilities of two diverse systems. In a recent paper, we presented a metric to quantify diversity among several designs. The problem of calculating the diversity metric is NP-complete and can be of exponential complexity. In this paper, we present techniques to estimate the value of the design diversity metric. For datapath designs, we have formulated very fast techniques to calculate the value of the metric by exploiting the regularity in the datapath structures. For general combinational logic circuits, we present an adaptive Monte-Carlo simulation technique for estimating bounds on the value of the metric. The adaptive Monte-Carlo simulation technique provides accurate estimates of the design diversity metric; the number of simulations used to reach this estimate is polynomial (instead of exponential) in the number of circuit inputs. Moreover, the number of simulations can be tuned depending on the desired accuracy.
Scheduling and constraint propagation
Authors: Peter Brucker
Venue: Discrete Applied Mathematics (2002)

The resource-constrained project-scheduling problem (RCPSP) and some of its generalizations are defined. Furthermore, constraint propagation techniques for these problems and related machine scheduling problems are introduced and possible applications of these techniques in connection with lower bound calculations, branch-and-bound methods, and heuristics are discussed.
A boundary element analysis of the linear elasto-static axisymmetric contact problem of an infinite layered medium with a homogeneous body
Authors: Wenqing Wang, Haruo Ishikawa
Venue: Advances in Engineering Software (2003)

A boundary element method for analyzing the linear elasto-static frictionless axisymmetric contact problem of a multi-layered medium with a homogeneous body is presented in this work. In the present method, the boundary element method using Kelvin's fundamental solution is employed to deal with the homogeneous body, while a newly developed boundary integral approach for linear elastostatic axisymmetric problems is utilized to evaluate the distributions of the stresses and displacements of the multi-layered medium in contact status. With the newly developed boundary integral approach for the multi-layered problems, the element discretization is only needed in the contact area of the multi-layered medium regardless of the variations of layer thickness, and the singularities that occur in the common boundary element are thoroughly avoided. Some numerical tests are carried out to show the efficiency of the present method.
A Tabu Search Heuristic for the Capacitated Arc Routing Problem
Authors: Alain Hertz, Gilbert Laporte, Michel Mittaz
Venue: Operations Research (2000)

The Capacitated Arc Routing Problem arises in several contexts where streets or roads must be traversed for maintenance purposes or for the delivery of services. A tabu search is proposed for this difficult problem. On benchmark instances, it outperforms all known heuristics and often produces a proven optimum.
A proposal for introducing model checking into an undergraduate software engineering curriculum
Authors: Hong Liu, David P. Gluch
Venue: Journal of Computing Sciences in Colleges (2002)

Model checking is a new pragmatic technology in formal methods. This paper presents a rationale and proposal for introducing model checking into an undergraduate software engineering curriculum. Supported by experiences in teaching model checking in a graduate program, we discuss a specific course design and solutions to potential problems in its implementation.
Asymptotic enumeration of sparse graphs with a minimum degree constraint
Authors: Boris Pittel, Nicholas C. Wormald
Venue: Journal of Combinatorial Theory Series A (2003)

We derive an asymptotic formula for the number of graphs with n vertices all of degree at least k, and m edges, with k fixed. This is done by summing the asymptotic formula for the number of graphs with a given degree sequence, all degrees at least k. This approach requires analysis of a set of independent truncated Poisson variables, which approximate the degree sequence of a random graph chosen uniformly at random among all graphs with n vertices, m edges, and a minimum degree at least k. Our main result generalizes a result of Bender, Canfield and McKay and of Korshunov, who treated the case k = 1 using different methods.
Design and simulation of structure-variable control systems based on multi-valued Lyapunov functions
Authors: F. Niewels, H. Kiendl
Venue: Systems Analysis Modelling Simulation (2002)

In this paper we consider the design of time continuous controllers for linear plants. A universal design concept for structure-variable controllers is summarized. The potential of multi-valued Lyapunov functions within this concept, in general, is highlighted and the concept is extended to make use of these functions. The key point of these extensions is a stability lemma that is based on multi-valued Lyapunov functions. The extended design concept supplies a better performance while still guaranteeing the stability of the resulting control system. The results are used in combination with a special version of the design concept, which is also summarized. Specific attention is paid to simulation aspects and the requirements arising from the multi-valued nature of the Lyapunov functions used. Finally, an example of an application is given.
Railway Timetabling Using Lagrangian Relaxation
Authors: U. Brannlund, P. O. Lindberg, A. Nou, J. E. Nilsson
Venue: Transportation Science (1998)

We present a novel optimization approach for the timetabling problem of a railway company, i.e., scheduling of a set of trains to obtain a profit maximizing timetable, while not violating track capacity constraints. The scheduling decisions are based on estimates of the value of running different types of service at specified times. We model the problem as a very large integer programming problem. The model is flexible in that it allows for general cost functions. We have used a Lagrangian relaxation solution approach, in which the track capacity constraints are relaxed and assigned prices, so that the problem separates into one dynamic program for each physical train. The number of dual variables is very large. However, it turns out that only a sm all fraction of these are nonzero, which one may take advantage of in the dual updating schemes. The approach has been tested on a realistic example suggested by the Swedish National Railway Administration. This example contains 18 passenger trains and 8 freight trains to be scheduled during a day on a stretch of single track, consisting of 17 stations. The computation times are rather modest and the obtained timetables are within a few percent of optimality.
Structure of weakly invertible semi-input-memory finite automata with delay 2
Authors: Renji Tao, Shihua Chen
Venue: Journal of Computer Science and Technology (2002)

Semi-input-memory finite automata, a kind of finite automata introduced by the author of this paper for studying error propagation, are a generalization of input-memory finite automata by appending an autonomous finite automaton component. This paper gives a characterization on the structure of weakly invertible semi-input-memory finite automata with delay 2 in which input alphabets and output alphabets have two elements and autonomous finite automata are cyclic. For the structure of feedforward inverse finite automata with delay 2, Zhu first gave a characterization; from a result on mutual invertibility of finite automata, the result mentioned above also leads to a different characterization on the structure of feedforward inverse finite automata with delay 2.
Efficient formalism-only parsing of XML/HTML using the §-calculus
Authors: Quinn Tyler Jackson
Venue: ACM SIGPLAN Notices (2003)

Traditionally, correct parsing of XML and HTML has been littered with semantic hacks in the parsing code to deal with the oddities of these languages, since HTML accepts unbalanced tags and tags that do not match in case, but XML is less forgiving. The detection of well-formedness of XML documents has, to date, required semantic analysis outside of the grammar specification. We present a grammar-only (HT\X)ML parser which, upon detecting that it is parsing XML, modifies itself dynamically in order to insure that the document conforms to XML'S stricter rules. Our grammar detects unbalanced tags in XML, as well as mismatched case in otherwise balanced tags, while, at the same time, requiring XML document tag's attribute values to be in quotes, but accepting the looser attribute syntax when in an HTML document. On a 733 MHz Windows 2000 machine, our parser did a wellformedness detecting parse on XML documents such as the KJV Old Testament at a rate of 92 Kb/second, the Austin's Pride and Prejudice at a rate of 108 Kb/second, and Wolfgang May 's Mondial 3.0 database at a rate of 149 Kb/second.