ppxscal/embedding_network huggingface dataset:
Is simple sequencing simple adaptive hypermedia?
Authors: Nor Aniza Abdullah, Hugh Davis
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

In this paper, we explore the differences between the Adaptive Hypermedia and IMS Simple Sequencing approaches. Both approaches provide learning material tailored for the learner's current context. Understanding the difference between the approaches enables us to identify the best features of each, and thus to identify research agendas for the improvement of adaptive hypermedia and of Web-based Learning Management Systems.
Evolutionary computation for evolutionary theory
Authors: C. C. Maley
Venue: Advances in evolutionary computing: theory and applications (2003)

Evolutionary computation has developed primarily as an engineering tool for finding solutions to difficult problems. In the shadow of this success, a revolution has been building in evolutionary theory. Evolutionary models, often quite similar to genetic algorithms, are being used to extend our theoretical understanding of biology. Evolutionary models can represent details of the biology that makes analytical models mathematically intractable. Evolutionary models may thus be used as checks on the simplifications of analytical models, as well as formalisms for exploring the consequences of a particular representation of a biological system. In the best of cases, evolutionary models act as biological theories, accounting for previous experimental results and making predictions for future results. In this way, evolutionary models are serving to reunite theoretical biology with experimental biology.
Minimum Distance Error Correction
Authors: J. A. Dain
Venue:  (1987)

A method is presented for incorporating error correction using a minimum distance measure into LR parsers. The method is suitable for use by an automatic parser-generator. State information in the LR parser stack at the point of detection of error is used to generate a set of strings which are potential repairs to the input. A string with least minimum distance from the actual input is chosen and the parser is restarted. Practical methods for generating the set of repairs are discussed. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Interactive Situation Models for Systems Development
Authors: Meurig Beynon, Richard Cartwright, Jaratsri Rungrattanaubol, Pi Sun
Venue:  (1999)

Devising principles for systems representation and analysis that can cope with the complexity of the interactions between programmable components and human agents in modern computing applications is a challenging and fundamental problem. Understanding the role of human and inanimate components within a reactive system, for instance, involves not only input-output transformations, but also communication and stimulus-response issues. This paper proposes novel computer-based interactive situation models to assist systems development. Such models provide an environment within which the human interpreter can explore the relationships between observables and the patterns of behaviour associated with a system component with particular reference to its external real-world semantics. They are constructed using principles based upon observation, agency and dependency ("Empirical Modelling") that have been developed at the University of Warwick. This paper describes and illustrates ! the characteristics of interactive situation models in detail, and concludes with a brief discussion of their potential significance for systems development.
Conditioning of the Steady State Semiconductor Service Problem
Authors: Uri Ascher, P. A. Markowich, C. Schmeiser, H. Steinruck, R. Weiss
Venue:  (1986)

When solving numerically the steady state semiconductor device problem using appropriate discretizations, extremely large condition numbers are often encountered for the linearized discrete device problem. These condition numbers are so large that, if they represented a sharp bound on the amplification of input errors, or even of roundoff errors, then the obtained numerical solution would be meaningless. As it turns out, one major reason for these large numbers is due to poor row and column scaling, which is essentially harmless and/or can be fixed. But another reason could be an ill-conditioned device, which yields a true loss of significant digits in the numerical calculation. In this paper we carry out a conditioning analysis for the steady state device problem. We consider various quasilinearizations as well as Gummel-type iterations and obtain stability bounds which may indeed allow ill-conditioning in general. These bounds are exponential in the potential variation, and are sharp e.g. for a thyristor. But for devices where each smooth subdomain has an Ohmic contact, e.g. a pn-diode, moderate bounds guaranteeing well-conditioning are obtained. Moreover, the analysis suggests how various row and column scalings should be applied in order for the measured condition numbers to correspond more realistically to the true loss of significant digits in the calculations.
A network-enhanced volume renderer
Authors: Jeff LaPorte
Venue:  (1997)

Volume renedering is superior in many respects to conventional methods of medical visualization. Extending this ability into the realm of telemedicine provides the opportunity for health professionals to offer expertise not normally available to smaller communities, via computer networking of health centers. This report describes such a software system for collaboration, a network-enhanced version of an existing program called Volren. The methods used to provide network functionality in Volren can serve as a prototype for future multiuser applications. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
The influence of repaired slabs in coupled shear walls
Authors: A. Nadjai, D. Johnson
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

This paper is concerned with the response of repair strengthening of slabs used to effect the coupling of shear walls. An experimental investigation of 1/2 scale reinforced concrete shear wall slab model is described. Based on the results of the model, an analytical simulation is used to investigate the response of planar coupled shear walls before and after repair of joints slabs to shear walls at the elasto-plastic case. The elasto-plastic condition is restricted to the connecting slabs using a convenient perfectly elastic/perfectly plastic material model. In addition, the work presents results obtained with the discrete force method and discusses its applicability to some representative problems.
A QoS-Sensitive Approach for Timeliness and Freshness Guarantees in Real-Time Databases
Authors: K. Kang, S. H. Son, J. A. Stankovic, T. F. Abdelzaher
Venue:  (2001)

The demand for real-time database services has been increasing recently. Examples include sensor data fusion, decision support, web information services, e-commerce, online trading, and data-intensive smart spaces. A real-time database, a core component of many information systems for real-time applications, can be a main service bottleneck. To address this problem, we present a real-time database QoS management scheme that provides guarantees on deadline miss ratio and data freshness, which are considered two fundamental performance metrics for real-time database services. Using our approach, admitted user transactions can be processed in a timely manner and data freshness can be guaranteed even in the presence of unpredictable workloads and data access patterns. A simulation study shows that our QoS-sensitive approach can achieve a significant performance improvement, in terms of deadline miss ratio and data freshness, compared to several baseline approaches. Furthermore, our approach shows a comparable performance to the theoretical oracle that is privileged by the complete future knowledge of data accesses.
Worlds Before and Beyond Words
Authors: W. B. Beynon, P. E. Ness, S. B. Russ
Venue:  (1996)

The advent of computer-generated environments for simulating experience of the real world invites a reappraisal of the role of classical and neo-classical theories of computation (e.g. views of computation based on linguistic and logical frameworks.) To make more effective use of computers in connection with Virtual Reality requires a shift in emphasis towards computers as state representers rather than calculators, towards the construction and analysis of environments rather than documents and towards empirical rather than theoretical approaches to knowledge representation. This paper discusses the prospects for gaining new insights into empirical activity through the systematic construction of models (typically - but not necessarily - computer based) in which real world state, as perceived by a particular agent, is imitated directly through the use of suitable metaphors. Such activity is exemplified in the construction of engineering models and the development and calibration of scientific instruments. A characteristic ingredient of the modelling processes involved in these applications is correlation of the results of experiments and observations that are performed in parallel in a real world environment and in the associated physical (e.g. computer) model. Conventional computer programming paradigms are not well-suited for constructing models by empirical methods. Amongst widely used software tools, only spreadsheets are well adapted to imitating real world state as it is captured through observation and experiment. The philosophical ideas to be introduced in the paper have been developed in connection with practical case-studies and software tools that contribute to a long-term Empirical Modelling Project being pursued at the Computer Science Department at the University of Warwick. A key concept in this research programme is the development of agent-oriented models in which the dependencies between observables that are used for communication are specified using generalised spreadsheet principles.
Interaction of Virtual Machine with the Operating System
Authors: Kiran Tati, Geoffrey M. Voelker
Venue:  (2002)

As applications executing in virtual machine runtime environments such as the Java Virtual Machine and the .NET Common Language Runtime become more prevalent on desktop operating systems, this trend raises the interesting question of the best model for supporting multiple applications in virtual machine environments. A natural model is to execute each application in its own virtual machine process. However, multiple applications could also be executed in a single virtual machine process by leveraging the protection and security features of the programming languages used by the applications. Executing within a single virtual machine process makes it easier to share code and data and communicate among the processes. In this paper, we present an intermediate model for supporting multiple applications in virtual machine environments for desktop operating systems. We argue that applications should take advantage of the protection features and resource management provided by the operating system and execute each application in its own virtual machine process. However, to facilitate code reuse, reduce application initialization time, and facilitate interprocess communication among applications in different virtual machines, we propose extending virtual machine implementations with the use of a shared class cache and an efficient serialization implementation optimized for local machine interprocess communication. To demonstrate and evaluate our approach, we describe the design and implementation of a shared class cache and optimized class serialization in the Java virtual machine, and evaluate our implementation using a set of application and micro-benchmarks.
Optimum design of reinforced concrete continuous beams by genetic algorithms
Authors: M. N. S. Hadi
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

This paper presents the application of genetic algorithms (GA) for the design of continuous reinforced concrete T and L beams based on the recommendations of the current Australian design standards. GA have been used for solving many engineering problems and have proved to be efficient in achieving the optimum solution very rapidly. In this study, the problem of the optimum design of T and L beams is formulated based on the requirements of the Australian design standard for concrete structures, AS3600. This optimisation problem was implemented by writing a computer program using Matlab. In order to evaluate the developed system, a number of examples were analysed and designed using the developed code. The evaluation proved that the produced design is economical, also it proved that developed program is efficient and versatile.
Link analysis for collaborative knowledge building
Authors: Harris Wu, Michael D. Gordon, Kurt DeMaagd, Nathan Bos
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

We present an ongoing research project utilizing navigation and hyperlink data to aid collaborative knowledge building. We allow collaborators to personally organize documents and other research resources and make references to them. We combine their personal organizations and references to develop a unified, hierarchical categorization of these resources. We analyze collaborators' navigations to identify prominent research activities as well as the key documents related to these activities. We examine prominence over time to identify research trends.
On the Modality of Convex Polygons
Authors: Karl Abrahamson
Venue:  (1987)

Under two reasonable definitions of random convex polygons, the expected modality of a random convex polygon grows without bound as the number of vertices grows. This refutes a conjecture of Aggarwall and Melville.
Pitfalls in the Numerical Solution of Linear Ill-Posed Problems
Authors: James M. Varah
Venue:  (1981)

Very special computational difficulties arise when attempting to solve linear systems arising from integral equations of the first kind. We examine here existence and uniqueness questions associated with so-called \underline{reasonable} solutions for such problems, and present results using the best- known methods on inverse Laplace transform problems. We also discuss the choice of free parameters occurring in these methods, from the same point of view.
Structure and behavior awareness in themis
Authors: Kenneth M. Anderson, Susanne A. Sherba, William V. Lepthien
Venue: Proceedings of the fourteenth ACM conference on Hypertext and hypermedia (2003)

Structural computing provides techniques and tools to ease the task of developing application infrastructure; infrastructure that provides common services such as persistence, naming, distribution, navigational hypermedia, etc., over a set of application-specific or domain-specific structures. Within structural computing, "structure" refers to a combination of data together with relationships pertaining to that data. Structure servers support the specification and manipulation of structures. One important aspect of structural computing is the power and flexibility it provides application developers constructing new applications. A large part of this power is due to structural computing's ability to provide awareness services for both structure and behavior. We define this concept and describe the awareness services provided by the Themis structural computing environment. The utility of these services are demonstrated by presenting the impact they have had on the InfiniTe information integration environment. In particular, these services help to increase the efficiency and reduce the size of domain-specific applications built using structural computing technology. We conclude by discussing how these services might influence the open hypermedia field and the development of new hypermedia services.
DISTRIBUTED DEGREE-CONSTRAINED MULTICASTING IN POINT-TO-POINT NETWORKS
Authors: Fred Bauer, Anujan Varma
Venue:  (1995)

Establishing a multicast tree in a point-to-point network of switch nodes, such as a wide-area ATM network, is often modeled as the NP-complete Steiner problem in networks. In this paper, we present distributed algorithms for finding efficient multicast trees in the presence of constraints on the copying ability of the individual switch nodes in the network. We refer to this problem as the degree-constrained multicast tree problem and model it as the degree-constrained Steiner problem (DCSP) in networks. We consider two distinct approaches to the design of distributed DCPS heuristics. The first approach involves design of distributed versions of centralized DCSP algorithms. We introduce distributed versions of two DCSP heuristics, SPH and K-SPH. The second approach is to modify the solution obtained from an unconstrained heuristic to satisfy the degree constraints using a distributed post-processing algorithm. We compare the algorithms by simulation based on three criteria: quality of solution, convergence time, and the number of unsolved networks. Our results show that each of the heuristics generated degree-constrained multicast trees within 10% of the best solution found. Surprisingly few test networks were unsolvable. The distributed post-processing heuristic presented is of particular interest since it may be used with any Steiner heuristic. When paired with a good unconstrained distributed Steiner heuristic, it gave away little quality of solution while converging rapidly.
Cooperative Learning in the Classroom: The Importance of a Collaborative Environment for Computer-Based Education
Authors: Kori Inkpen, Kellogg S. Booth, Maria Klawe, Rena Upitis
Venue:  (1994)

Cooperative Learning in the Classroom: The Importance of a Collaborative Envi ronment for Computer-Based Education Cooperative behavior of students playing an educational computer game was investigated. The combination of gender and whether one or two computers were present significantly affected the level of achievement as measured by the number of puzzles completed in the game. Female/Female pairs playing on two computers, on average, completed less puzzles than any other pairs in any other condition. Differences were also observed for gender pairs sharing control of the mouse while playing on a single computer. Male/Male pairs had a higher number and percentage of refusals to give up control of the mouse.
Management Indicators: Assessing Product Reliability and Maintainability
Authors: Constance V. Rosson
Venue:  (1988)

This report discusses the role of Management Indicators in validating the predictive capability of the bottom-up evaluation process, which is defined by the Procedural Approach to the Evaluation of Software Development Methodologies. The bottom-up evaluation process provides a framework for determining the extent to which software engineering objectives, e.g., reliability and maintainability, are present in a software product from a design perspective of the code and supporting documentation. The bottom-up evaluation process is observed to be a predictor of the extent to which the objectives are realized in the post-developed product. Employment of the bottom-up evaluation process to determine the extent to which the objectives are present in the product is accomplished by the utilization of Design Indicators. Management Indicators are proposed as a counterpart to Design Indicators and enable one to measure the extent to which the objectives are realized in a developed product. While Design Indicators focus on design structure characteristics of the product, Management Indicators focus on the acquisitional, behavioral, and maintenance characteristics. To accomplish the validation of the predictive capability, the correlation between the values obtained by utilizing Design Indicators and those obtained by utilizing Management Indicators must be investigated. The author has chosen to study and present the software engineering objectives of reliability and maintainability as they related to a future validation effort. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Derandomization, Witnesses for Boolean Matrix Multiplication and Construction of Perfect Hash Functions
Authors: N. Alon, M. Naor
Venue:  (1994)

Small sample spaces with almost independent random variables are applied to design efficient sequential deterministic algorithms for two problems. The first algorithm, motivated by the attempt to design efficient algorithms for the All Pairs Shortest Path problem using fast matrix multiplication, solves the problem of computing witnesses for the Boolean product of two matrices. That is, if A and B are two n by n matrices, and C = AB is their Boolean product, the algorithm finds for every entry C>sub<ij>/sub< = 1 a witness: an index k so that A>sub<ik>/sub< = B>sub<kj>/sub< = 1. Its running time exceeds that of computing the product of two n by n matrices with small integer entries by a polylogarithmic factor. The second algorithm is a nearly linear time deterministic procedure for constructing a perfect hash function for a given n-subset of {1,?,m}.
Device Independent Perspective Volume Rendering Using Octrees
Authors: Timothy L Ryan, Clifford A. Shaffer
Venue:  (1992)

This paper describes a reasonably fast, space efficient algorithm for volume rendering. The algorithm is device independent since it is written as an X Windows client. It makes no graphics calls to dedicated graphics hardware, but allows the X server to take advantage of such hardware when it exists. It can be run on any machine that supports X windows, from an IBM-PC to a high-end graphics workstation. It produces a perspective projection of the volume, since perspective projections are generally easier to interpret than parallel projections. The algorithm uses progressive refinement to give the user a quick view of the dataset and how it is oriented. If a different orientation or dataset is desired, the user may interrupt the rendering process. Once the desired dataset and position have been determined, the progressive refinement process continues and the image improves in quality until the greatest level of detail is displayed.