ppxscal/embedding_network huggingface dataset:
Object-oriented classic data structures for CS 2 in visual basic .net
Authors: H. Paul Haiduk
Venue: Journal of Computing Sciences in Colleges (2002)

For many years there has been substantial agreement that the content of the CS2 course should be a study of the classic data structures including, but not limited to, stacks, queues, trees, and tables. In recent years we have observed a move to the object-oriented programming paradigm for the CS2 course. At this point there is significant divergence as to the "best" programming language to use - C++, Eiffel, Java, Oberon, Python, or Scheme, to name a few. Although many agree that to be truly object-oriented, a programming language must support (1) encapsulation of attributes and behavior in a user-defined class specification, (2) instantiation of objects of pre-defined and user-defined classes, (3) polymorphism, and (4) inheritance. From a survey of recent texts for the CS2 course, it appears that there is heavy emphasis on encapsulation and instantiation with some treatment of inheritance and little treatment of polymorphism. There is also significant treatment of generic container classes supported by template classes if the supporting language is C++. If the supporting language is Java, then the container typically manages objects of the type Object. This paper makes a case that Visual Basic .NET could be considered a viable candidate for the CS2 course since it supports user-defined class specifications with the encapsulation of attributes and behavior, instantiation of objects of pre-defined and user-defined classes, polymorphism and inheritance. Additionally, there is full support for exception handling using the now, well-known, try/catch/finally semantics. Further, there is support for dynamic memory allocation and deallocation. And finally, the student or developer has full support for visual, event-driven, net-centric programming paradigm.This paper is a follow-up to a series of papers several years ago by the same author. These papers made a case for the use of Visual Basic in CS2 even though, at the time, Visual Basic was not yet fully object-oriented. This paper will present an implementation of a stack container ADT that is fully generic, that is, it may manage a collection of arbitrary objects that demonstrate polymorphic behavior.
Languages, D0L-systems, sets of curves, and surface automorphisms
Authors: Luis-Miguel Lopez, Philippe Narbel
Venue: Information and Computation (2003)

We introduce, extend and apply some relationships between formal language theory and surface theory. First we show how boundaries of languages topologized with the Cantor metric can be mapped to sets of curves on surfaces, namely laminations. Second we present how and when endomorphisms of free monoids, i.e. substitutions, can be mapped to automorphisms of surfaces, so that D0L-systems correspond to iterations of these automorphisms. Third, we apply these ideas to construct sets of non-periodic irreducible automorphisms of surfaces following [14,35,43], so that the involved proofs do not use any differential or algebraic tools, but, accordingly, substitution and D0L-system theory of [11,12,31,32,37] - mainly the decidability for a D0L-language [12] to be strongly repetitive or not. This construction also yields effective symbolic descriptions of the stable sets of curves associated with these automorphisms.
Creating effective online narrated presentations
Authors: Roger Von Holzen, Darla Runyon
Venue: Journal of Computing Sciences in Colleges (2002)

In the move from an on campus teaching environment to an online learning environment, many instructors simply redeploy their classroom PowerPoint presentations. Though very useful in face-to-face settings, online students often find that these simple PowerPoint slides are ineffective learning tools. Either the presentations contain insufficient information or they are too difficult to access using a 28.8 modem.When planning to create effective online presentations using PowerPoint, instructors now have a powerful tool to assist them in their efforts. RealPresenter, by Real Networks, allows an instructor to enhance his or her PowerPoint presentations by being able to add audio to the slide shows. By incorporating voice-over narration into their online presentations, instructors may nowadd an audio component to complement their slides' visuals and the text. When completed, the file format of such presentations may then be compressed for delivery across an online setting.The purpose of this presentation is to provide an explanation of how to plan, develop and execute an effective online, narrated presentation using PowerPoint. The following major steps involved in planning such a slide presentation will be covered: 1. Selecting focused, learner-centered content suitable for the desired format; 2. Designing the layout of the specific slides to be incorporated into the presentation (font types and sizes, color scheme, graphics, clip art, etc.); 3. Incorporating voice-over narration; and 4. Compressing and delivering the final presentation product.Participants in this presentation will be provided with a wide variety of examples of effective online, narrated presentations; instructions on how to add voice-over narration to PowerPoint presentations and how to compress the file format for Web delivery; and insight as to how to incorporate these presentation into the learing process to complement other teaching techniques. In addition, a PowerPoint-based video and audio system called Tegrity will also be demonstrated.
Santa Fe Railway Uses An Operating-Plan Model to Improve its Service Design
Authors: A. Ben-Tal, A. Nemirovski, Michael F. Gorman
Venue: Interfaces (1998)

Santa Fe Railway's intermodal business unit has developed an innovative approach to designing its service offerings. The operating-plan model (OPM) minimizes the schedule-related costs of service subject to rail-operating capabilities while meeting customers' expectations for service. The algorithm produces a weekly train timetable and assigns traffic to trains. Because of the problem's size and complexity, a combination of genetic and tabu searches is used to search for successively better operating plans. The OPM shows the potential to improve global service by four percent while reducing costs by six percent over the existing operating plan. Santa Fe Intermodal has realized savings by applying the OPM to more narrowly focused problems.
A linear logical framework
Authors: Iliano Cervesato, Frank Pfenning
Venue: Information and Computation (2002)

We present the linear type theory λΠ-o&T as the formal basis for LLF, a conservative extension of the logical framework LF. LLF combines the expressive power of dependent types with linear logic to permit the natural and concise representation of a whole new class of deductive systems, namely those dealing with state. As an example we encode a version of Mini-ML with mutable references including its type system and its operational semantics and describe how to take practical advantage of the representation of its computations.
Effective timestamping in databases
Authors: Kristian Torp, Christian S. Jensen, Richard Thomas Snodgrass
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (2000)

Many existing database applications place various timestamps on their data, rendering temporal values such as dates and times prevalent in database tables. During the past two decades, several dozen temporal data models have appeared, all with timestamps being integral components. The models have used timestamps for encoding two specific temporal aspects of database facts, namely transaction time, when the facts are current in the database, and valid time, when the facts are true in the modeled reality. However, with few exceptions, the assignment of timestamp values has been considered only in the context of individual modification statements.This paper takes the next logical step: It considers the use of timestamping for capturing transaction and valid time in the context of transactions. The paper initially identifies and analyzes several problems with straightforward timestamping, then proceeds to propose a variety of techniques aimed at solving these problems. Timestamping the results of a transaction with the commit time of the transaction is a promising approach. The paper studies how this timestamping may be done using a spectrum of techniques. While many database facts are valid until now, the current time, this value is absent from the existing temporal types. Techniques that address this problem using different substitute values are presented. Using a stratum architecture, the performance of the different proposed techniques are studied. Although querying and modifying time-varying data is accompanied by a number of subtle problems, we present a comprehensive approach that provides application programmers with simple, consistent, and efficient support for modifying bitemporal databases in the context of user transactions.
The Circuit-Switched Network Design and Analysis Model: A Chronology of Its Development and Use
Authors: Harry G. Barker, David A. Calabrese, Martin J. Fischer, David A. Garbin, J. Edward Knepley, Gregor W. Swinsky
Venue: Operations Research (2002)

The Defense Information System Agency (DISA) has managerial and engineering responsibility for a circuit-switched network currently known as the Defense Information System Network--Voice. This network was originally implemented in the 1960s and was known as the Automatic Voice Network. Throughout this time, DISA has used a network design and analysis model to reconfigure the network. This model was developed in the early 1970s, has been continually enhanced, and is used on a weekly basis to engineer and manage the network. Since 1975, it has been used to save the United States (U.S.) government approximately $1,400,000,000.00. In this paper, we present a chronology of its development, enhancement, and use.
Limit Cycles for Multidimensional Vector Fields. The Elliptic Case
Authors: Marcin Bobieński, Henryk Żoładek
Venue: Journal of Dynamical and Control Systems (2003)

We consider polynomial vector fields of the form \.{x} = 2_y + zR(x,y), \.{y} = 3x^2 - 3 + zS(x,y), \.{z} = A_x,y)z, z \epsilon \Ropf^v, and their polynomial perturbations of degree &les;n. We present a sufficient condition that the perturbed system has an invariant surface close to the plane z = 0. We study limit cycles which appear on this surface. The linearized condition for limit cycles, bifurcating from the curves y2 &minus; x3 + 3x = h, leads to a certain 2- dimensional integral (which generalizes the elliptic integrals). We show that this integral has a representation R1(h)I1 + &sdot;&sdot;&sdot; + Re(h)Ie, where Rj(h) are rational functions with degrees of numerators and denominators bounded by O(n). In the case of constant and one-dimensional matrix A(x,y) we estimate the number of zeros of the integral by const &sdot;n.
Multi-objective optimization problems with fuzzy relation equation constraints
Authors: Jiranut Loetamonphong, Shu-Cherng Fang, Robert E. Young
Venue: Fuzzy Sets and Systems (2002)

This paper studies a new class of optimization problems which have multiple objective functions subject to a set of fuzzy relation equations. Since the feasible domain of such a problem is in general non-convex and the objective functions are not necessarily linear, traditional optimization methods may become ineffective and inefficient. Taking advantage of the special structure of the solution set, a reduction procedure is developed to simplify a given problem. Moreover, a genetic-based algorithm is proposed to find the "Pareto optimal solutions". The major components of the proposed algorithm together with some encouraging test results are reported.
Decision Support Systems Support the Search for Win-Win Solutions in Railway Network Design
Authors: Jurjen S. Hooghiemstra, Leo G. Kroon, Michiel A. Odijk, Marc Salomon, Peter J. Zwaneveld
Venue: Interfaces (1999)

Railned is an independent organization that advises the Dutch government on investments in future railway infrastructure. It generates and evaluates infrastructural scenarios that stem from the government's objectives and those of the operators of the railway network, the Dutch railway company Nederlandse Spoorwegen (NS) being by far the largest. The government and the railway operators often have different objectives, which may conflict sometimes. The government finances and manages the infrastructure, and wants to meet certain social and environmental priorities, thereby not exceeding budget limits. The operators exploit the infrastructure and wish to have a dependable infrastructure that guarantees long-term profitability. Railned uses various decision support systems (DSS) to develop and analyze infrastructural scenarios that yield win-win solutions for both the Dutch government andthe railway operators.
Performance issues and error analysis in an open-domain question answering system
Authors: Dan Moldovan, Marius Paşca, Sanda Harabagiu, Mihai Surdeanu
Venue: ACM Transactions on Information Systems (TOIS) (2003)

This paper presents an in-depth analysis of a state-of-the-art Question Answering system. Several scenarios are examined: (1) the performance of each module in a serial baseline system, (2) the impact of feedbacks and the insertion of a logic prover, and (3) the impact of various retrieval strategies and lexical resources. The main conclusion is that the overall performance depends on the depth of natural language processing resources and the tools used for answer finding.
Optimal Routing of Customers to Two Parallel Heterogeneous Servers: the Case of Ihr Service Times
Authors: Esther Frostig, Benny Levikson
Venue: Operations Research (1999)

We consider here the optimal routing of customers, arriving to a system consisting of two heterogeneous parallel servers. The service times of the two servers have an increasing hazard rate. The arrival process is a general renewal process. The cost of holding x customers in the system per time unit is a nondecreasing and convex function. The objective is to minimize the expected discounted holding cost. We show some monotonicity properties of the optimal policy. Then we show that the optimal policy routes an arriving customer to the fastest server whenever this server has the lowest workload.
A numerical comparison of partial solutions in the decomposition method for linear and nonlinear partial differential equations
Authors: Dogan Kaya, Asif Yokus
Venue: Mathematics and Computers in Simulation (2002)

In this study, the decomposition method for solving the linear heat equation and nonlinear Burgers equation is implemented with appropriate initial conditions. The application of the method demonstrated that the partial solution in the x-direction requires more computational work when compared with the partial solution developed in the t-direction but the numerical solution in the x-direction are performed extremely well in terms of accuracy and efficiency.
Perspectives on the Evolution of Simulation
Authors: Richard E. Nance, Robert G. Sargent
Venue: Operations Research (2002)

Simulation is introduced in terms of its different forms and uses, but the focus on discrete event modeling for systems analysis is dominant as it has been during the evolution of the technique within operations research and the management sciences. This evolutionary trace of over almost fifty years notes the importance of bidirectional influences with computer science, probability and statistics, and mathematics. No area within the scope of operations research and the management sciences has been affected more by advances in computing technology than simulation. This assertion is affirmed in the review of progress in those technical areas that collectively define the art and science of simulation. A holistic description of the field must include the roles of professional societies, conferences and symposia, and publications. The closing citation of a scientific value judgment from over 30 years in the past hopefully provides a stimulus for contemplating what lies ahead in the next 50 years.
Fifteen consecutive integers with exactly four prime factors
Authors: Tony Forbes
Venue: Mathematics of Computation (2002)

We describe a successful search for a sequence of fifteen consecutive integers, each the product of exactly four prime factors. Fifteen is best possible.
Distributed modelling of Lake Tonle Sap catchment
Authors: H. Lauri, M. Virtanen
Venue: Development and application of computer techniques to environmental studies (2002)

A distributed hydrological model system with a graphical user interface will be applied to Lake Tonle Sap catchment. The main goal of the modelling project is to estimate the quantity and quality of water ending to the lake from nearby catchment areas, and thus provide input to a hydrodynamic lake model. The Lake Ton Le Sap has interesting hydrodynamics, as it is filled during monsoon time by the waters from the Mekong River, and has natural annual surface water level variation of about 7 meters. The final hydrological model system will consist of a distributed hydrological model, a graphical user interface, connections to databases, and GIS functionality. The user interface component provides model experts full access to model properties, but also enables nonexpert users to apply the system for standard computations.
The equation A &#x2297; x = B &#x2297; y over (max, +)
Authors: R. A. Cuninghame-Green, P. Butkovic
Venue: Theoretical Computer Science (2003)

For the two-sided homogeneous linear equation system A ⊗ x = B ⊗ y over (max, +), with no infinite rows or columns in A or B, an algorithm is presented which converges to a finite solution from any finite starting point whenever a finite solution exists. If the finite elements of A, B are all integers, convergence is in a finite number of steps, for which a precise bound can be calculated if moreover one of A, B has only finite elements. The algorithm is thus pseudopolynomial in complexity.
Temporal correlations in stochastic networks of spiking neurons
Authors: Carsten Meyer, Carl van Vreeswijk
Venue: Neural Computation (2002)

The determination of temporal and spatial correlations in neuronal activity is one of the most important neurophysiological tools to gain insight into the mechanisms of information processing in the brain. Its interpretation is complicated by the difficulty of disambiguating the effects of architecture, single-neuron properties, and network dynamics. We present a theory that describes the contribution of the network dynamics in a network of "spiking" neurons. For a simple neuron model including refractory properties, we calculate the temporal cross-correlations in a completely homogeneous, excitatory, fully connected network in a stable, stationary state, for stochastic dynamics in both discrete and continuous time. We show that even for this simple network architecture, the crosscorrelations exhibit a large variety of qualitatively different properties, strongly dependent on the level of noise, the decay constant of the refractory function, and the network activity. At the critical point, the crosscorrelations oscillate with a frequency that depends on the refractory properties or decay exponentially with a diverging damping constant (for "weak" refractory properties). We also investigate the effect of the synaptic time constants. It is shown that these time constants may, apart from their influence on the asymmetric peak arising from the direct synaptic connection, also affect the long-term properties of the cross-correlations.
LMR, DTA: adaptive communication algorithms for asynchronous real-time distributed systems using token-ring networks
Authors: Binoy Ravindran
Venue: Journal of Systems and Software (2003)

We present two adaptive communication algorithms called LMR and DTA, for asynchronous real-time distributed systems that use IEEE 802.5 token-ring networks and FDDI networks, respectively. The objective of the algorithms is to minimize end-to-end missed-deadline ratio of application tasks. While LMR adapts application tasks to workload fluctuations by reprioritizing transnode application messages, DTA performs adaptation by dynamically changing token holding times of host machines, respectively. We study the performance of the algorithms through benchmark-driven experimental studies. The performance of the algorithms is compared with an adaptive resource allocation algorithm that performs adaptation by dynamically replicating application processes for load sharing. The experimental results indicate that LMR and DTA outperform the process replication algorithm for load patterns that cause communication latencies to grow faster than execution latencies. Furthermore, we observe that LMR and DTA perform as "good" as the process replication algorithm for load patterns that cause execution latencies to grow faster than communication latencies.
Direct constructions of universal extended H systems
Authors: Pierluigi Frisco
Venue: Theoretical Computer Science (2003)

A direct universal extended H system receives as input the coding of an extended H system with a particular control mechanism and simulates it. We present a direct construction for five kinds of control for the extended H systems under consideration. It is the first time that a direct construction is described: universal results obtained until now were based on the simulation of universal type-0 grammars or Turing machine.
Hierarchical ordering of sequential processes
Authors: Edsger W. Dijkstra
Venue: The origin of concurrent programming: from semaphores to remote procedure calls (2002)

One of the primary functions of an operating system is to rebuild a machine that must be regarded as non-deterministic (on account of cycle stealing and interrupts) into a more or less deterministic automaton. Taming the degree of indeterminacy in steps will lead to a layered operating system. A bottom layer will be discussed and so will the adequacy of the interface it presents. An analysis of the requirements of the correctness proofs will give us an insight into the logical issues at hand. A "director-secretary" relationship will be introduced to reflect a possible discipline in the use of sequencing primitives.
Pomsets for local trace languages
Authors: Dietrich Kuske, Rémi Morin
Venue: Journal of Automata, Languages and Combinatorics (2001)

Mazurkiewicz traces can be seen as equivalence classes of words or as pomsets. Their generalization by local traces was formalized by HOOGERS, KLEIJN and THIAGARAJAN as equivalence classes of step firing sequences. First we introduce a pomset representation for local traces. Extending Büchi's Theorem and a previous generalization to Mazurkiewicz traces, we show then that a local trace language is recognized by a finite step transition system if and only if its class of pomsets is bounded and definable in Monadic Second Order logic.