ppxscal/embedding_network huggingface dataset:
Comparing the roles of representations in face-to-face and online computer supported collaborative learning
Authors: Daniel D. Suthers, Christopher D. Hundhausen, Laura E. Girardeau
Venue: Computers Education (2003)

This paper reports an empirical study comparing the role of discourse and knowledge representations (graphical evidence mapping) in face-to-face versus synchronous online collaborative learning. Prior work in face-to-face collaborative learning situations has shown that the features of representational notations can influence the focus of learners' discourse and collaborative activities. Two hypotheses were considered in the present study: (1) The influence of knowledge representations in the online condition could be weaker because of the lack of shared awareness and meaning that results from working together in front of a physically shared display, and because of the greater difficulty of utilizing the representations as a resource for conversation through gestural deixis, and (2) The influence of knowledge representations in the online study could be stronger because participants must rely more on them to compensate for the absence of face-to-face modes of communication. Quantitative results largely support the second hypothesis. There was greater consideration of certain coding categories supported by the knowledge representation software. However, essay quality and other observations provide indirect support for the first hypothesis. Explanations for these results and implications for the design of online collaborative learning environments are provided.
Intelligent metasearch engine for knowledge management
Authors: Eui-Hong Han, George Karypis, Doug Mewhort, Keith Hatchard
Venue: Proceedings of the twelfth international conference on Information and knowledge management (2003)

The explosive growth of available information sources and the resulting information overload pose several problems for users in many business organizations and educational institutions. First, searching through several information sources, one at a time, is a source of enormous frustration for users. Second, top-ranked documents in search results are frequently irrelevant to what users are interested in. To address these problems, we have developed ixmeta™, a powerful metasearch engine that gathers, evaluates, ranks, and reports the most relevant results from multiple information sources, including library catalogs, proprietary databases, intranets, and Web search engines. In addition to basic metasearch capabilities, ixmetafind uses personalization and clustering techniques to find the most relevant results for users. In this paper, we briefly describe technologies used in ixmetafind and present pinpoint™ from Sagebrush Corporation, the smart research tool™ in the kindergarten through twelfth grade (K-12) school environment. Pinpoint showcases ixmetafind in the knowledge management domain of the K-12 school environment.
The reciprocity relation of the Selberg function
Authors: Katsuhisa Mimachi, Masaaki Yoshida
Venue: Journal of Computational and Applied Mathematics (2003)

The reciprocity relation of the Beta function is reformulated, and that of the Selberg function is presented.
Interlingua-based English&ndash;Korean Two-way Speech Translation of Doctor&ndash;Patient Dialogues with CCLINC
Authors: Young-Suk Lee, Daniel J. Sinder, Clifford J. Weinstein
Venue: Machine Translation (2002)

Development of a robust two-way real-time speech translation system exposes researchers and system developers to various challenges of machine translation (MT) and spoken language dialogues. The need for communicating in at least two different languages poses problems not present for a monolingual spoken language dialogue system, where no MT engine is embedded within the process flow. Integration of various component modules for real-time operation poses challenges not present for text translation. In this paper, we present the CCLINC (Common Coalition Language System at Lincoln Laboratory) English&ndash;Korean two-way speech translation system prototype trained on doctor&ndash;patient dialogues, which integrates various techniques to tackle the challenges of automatic real-time speech translation. Key features of the system include (i) language&ndash;independent meaning representation which preserves the hierarchical predicate&ndash;argument structure of an input utterance, providing a powerful mechanism for discourse understanding of utterances originating from different languages, word-sense disambiguation and generation of various word orders of many languages, (ii) adoption of the DARPA Communicator architecture, a plug-and-play distributed system architecture which facilitates integration of component modules and system operation in real time, and (iii) automatic acquisition of grammar rules and lexicons for easy porting of the system to different languages and domains. We describe these features in detail and present experimental results.
Mining Semantic Networks for Knowledge Discovery
Authors: K. Rajaraman, Ah-Hwee Tan
Venue: Proceedings of the Third IEEE International Conference on Data Mining (2003)

This paper addresses the problem of mining a class ofsemantic networks, called Concept Frame Graphs (CFG's),for knowledge discovery from text. This new representationis motivated by the need to capture richer text content sothat non-trivial mining tasks can be performed. We firstdefine the CFG representation and then describe a rule-basedalgorithm for constructing a CFG from text documents.Treating the CFG as a networked knowledge base,we propose new methods for text mining. On a specific taskof discovering the top companies in an area, we observe thatour approach leads to simpler content mining algorithms,once the CFG has been constructed. Moreover, exploitingthe network structure of CFG results in significant improvementsin precision and recall.
Use of Online Systems in Clinical Medical Assessments: An Analysis of Physician Acceptance of Online Disability Evaluation Systems
Authors: Thomas A. Horan, Bengisu Tulu, Brian Hilton, Jacqueline Burton
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 6 - Volume 6 (2004)

In today's world of ever increasing amounts of information, hospitals and medical groups mustcontinually find ways to manage the myriad information that is gathered on patients. This realitymakes the field of medicine well suited to benefit from integrative and online information systems. However, research reveals that at times physicians resist the use of Information Technology (IT) in the clinical setting. This paper seeks to develop a conceptual model forphysician acceptance and test this socio-work structure model using a nationwide survey of physicians (n=141) conducted by the authors. The domain focus of this study is physician acceptance of an online disability evaluation system for generating and managing medical examination reports. The survey measured whether behavioral intention to use the new system varied as a function of IT infrastructure, organizational processes relating to IT, physician experience with computer use in clinical settings, and both specific and general attitudes toward IT use in clinical settings. Survey findings suggest that each of these factors affects behavioral intention to use online disability evaluation systems, and that these factors are more important than generalized attitudes toward online systems or socio-demographic predictors. These findings suggest that work-system variables are important when considering physicians use of online systems. This extends traditional use of TAM to consider organizational factors when analyzing the acceptance decision.
Mining Informative Rule Set for Prediction
Authors: Jiuyong Li, Hong Shen, Rodney Topor
Venue: Journal of Intelligent Information Systems (2004)

Mining transaction databases for association rules usually generates a large number of rules, most of which are unnecessary when used for subsequent prediction. In this paper we define a rule set for a given transaction database that is much smaller than the association rule set but makes the same predictions as the association rule set by the confidence priority. We call this rule set informative rule set. The informative rule set is not constrained to particular target items; and it is smaller than the non-redundant association rule set. We characterise relationships between the informative rule set and non-redundant association rule set. We present an algorithm to directly generate the informative rule set without generating all frequent itemsets first that accesses the database less frequently than other direct methods. We show experimentally that the informative rule set is much smaller and can be generated more efficiently than both the association rule set and non-redundant association rule set.
Monolingual Document Retrieval for European Languages
Authors: Vera Hollink, Jaap Kamps, Christof Monz, Maarten De Rijke
Venue: Information Retrieval (2004)

Recent years have witnessed considerable advances in information retrieval for European languages other than English. We give an overview of commonly used techniques and we analyze them with respect to their impact on retrieval effectiveness. The techniques considered range from linguistically motivated techniques, such as morphological normalization and compound splitting, to knowledge-free approaches, such as n-gram indexing. Evaluations are carried out against data from the CLEF campaign, covering eight European languages. Our results show that for many of these languages a modicum of linguistic techniques may lead to improvements in retrieval effectiveness, as can the use of language independent techniques.
?????: a first step
Authors: Timothy Davis, Robert Geist, Sarah Matzko, James Westall
Venue: Proceedings of the 35th SIGCSE technical symposium on Computer science education (2004)

A new approach to the design of the computing curriculum for a Bachelor of Arts degree is described. The approach relies extensively on problem-based instruction and computer graphics to teach key concepts in computer science. The novelty arises from the magnitude and origin of the problems to be integrated into the curriculum and the breadth of the impact across the curriculum. Results from a trial course, the first experiment with the new approach, are described. The course, Tools and Techniques for Software Development, is a sophomore-level course in programming methodology. Construction of a ray-tracing system (for generating synthetic images) was the vehicle chosen for the instruction.
A Class of Spectral Two-Level Preconditioners
Authors: B. Carpentieri, I. S. Duff, L. Giraud
Venue: SIAM Journal on Scientific Computing (2003)

It is well known that the convergence of Krylov methods for solving the linear system often depends to a large extent on the eigenvalue distribution. In many cases, it is observed that ``removing'' the smallest eigenvalues can greatly improve the convergence. Several techniques have been proposed in the past few years that attempt to tackle this problem. The proposed approaches can be split into two main families depending on whether the scheme enlarges the generated Krylov space or adaptively updates the preconditioner. In this paper, we follow the second approach and propose a class of preconditioners both for unsymmetric and for symmetric linear systems that can also be adapted for symmetric positive definite problems. We effectively solve the preconditioned system exactly in the low dimensional space associated with the smallest eigenvalues and use this to update the preconditioned residual. This update results in shifting eigenvalues from close to the origin to near to one for the new preconditioner. This is ideal when there are only a few eigenvalues near the origin while all the others are close to one because the updated preconditioned system becomes close to the identity. We illustrate the performance of our method through extensive numerical experiments on a set of general linear systems. Finally, we show the advantages of the preconditioners for solving dense linear systems arising in electromagnetism applications, which were the main motivation for this work.
Extensional normalisation and type-directed partial evaluation for typed lambda calculus with sums
Authors: Vincent Balat, Roberto Di Cosmo, Marcelo Fiore
Venue: ACM SIGPLAN Notices (2004)

We present a notion of η-long β-normal term for the typed lambda calculus with sums and prove, using Grothendieck logical relations, that every term is equivalent to one in normal form. Based on this development we give the first type-directed partial evaluator that constructs %able to construct normal forms of terms in this calculus.
A note on the greedy algorithm for the unsplittable flow problem
Authors: Petr Kolman
Venue: Information Processing Letters (2003)

In a recent paper Chekuri and Khanna improved the analysis of the greedy algorithm for the edge disjoint paths problem and proved the same bounds also for the related uniform capacity unsplittable flow problem. Here we show that their ideas can be used to get the same approximation ratio even for the more general Unsplittable Flow Problem with nonuniform edge capacities.
Bipartite Coverings of Graphs
Authors: Vojtech Rödl, Andrzej Ruciński
Venue: Combinatorics, Probability and Computing (1997)

In this note we give a probabilistic proof of the existence of an n-vertex graph Gn, n=1, 2, ..., such that, for some constant c>0, the edges of Gn cannot be covered by n&minus;c log n complete bipartite subgraphs of Gn. This result improves a previous bound due to F. R. K. Chung and is the best possible up to a constant.
Computer literacy for disadvantaged adults using computer-based training
Authors: Jesse Chou
Venue:  (2003)

This study explored the use and effectiveness of teaching computer literacy skills to disadvantaged adults using off-the-shelf multimedia computer-based training (CBT). A case study was conducted in a rural county of east Texas using referrals from two local organizations providing free computer literacy training to disadvantaged adults. This case study was an attempt to teach disadvantaged individuals using CBT at a particular location at a particular time. The case study included a statistical analysis (t tests using matched pairs) of data from the CBT pretests and posttests to determine the effectiveness of the training in increasing computer literacy skills within the target population. As measured by this study, CBT is an effective method for training disadvantaged groups in basic computer skills when augmented with lab assistants. CBT may be a viable alternative to traditional classroom instruction to help reach such populations not only in the location of the study but wherever traditional classes are not sufficient to reach everyone in need. The ability to offer the exact training needed by an individual at a convenient time and the ability to repeat the training make this an especially good alternative.
3D modeling of trees from freehand sketches
Authors: Makoto Okabe, Takeo Igarashi
Venue: ACM SIGGRAPH 2003 Sketches Applications (2003)

We will present a user interface for quickly and easily modeling three-dimensional (3D) botanical trees from freehand sketches. The system generates 3D geometry from a two-dimensional (2D) sketch based on the assumption that trees spread their branches uniformly. Several editing operations are implemented, such as adding, cutting, and erasing branches. Our system also predicts, and generates, branches automatically. The user can continue editing a 3D tree by selecting the predicted branches. The interface of our system allows novices to design reasonably natural-looking trees quickly and interactively as compared with the interfaces of rule-based systems designed for expert users (e.g., L-systems).
A Branching Process Approximation to Cascading Load-Dependent System Failure
Authors: Ian Dobson, Benjamin A. Carreras, David E. Newman
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 2 - Volume 2 (2004)

Networked infrastructures operated under highly loaded conditions are vulnerable to catastrophic cascading failures. For example, electric power transmission systems must be designed and operated to reduce the risk of widespread blackouts caused by cascading failure. There is a need for analytically tractable models to understand and quantify the risks of cascading failure. We study a probabilistic model of loading dependent cascading failure by approximating the propagation of failures as a Poisson branching process. This leads to a criticality condition for the failure propagation. At criticality there are power tails in the probability distribution of cascade sizes and consequently considerable risks of widespread catastrophic failure. Avoiding criticality or supercriticality is a key approach to reduce this risk. This approach of minimizing the propagation of failure after the cascade has started is complementary to the usual approach of minimizing the risk of the .rst few cascading failures. The analysis introduces a saturating form of the generalized Poisson distribution so that supercritical systems with a high probability of total failure can be considered.
Managing digital memories with the FXPAL photo application
Authors: John Adcock, Matthew Cooper, John Doherty, Jonathan Foote, Andreas Girgensohn, Lynn Wilcox
Venue: Proceedings of the eleventh ACM international conference on Multimedia (2003)

The FXPAL Photo Application is designed to faciliate the organization of digital images from digital cameras and other sources through automated organization and intuitive user interfaces.
A Nonnegatively Constrained Convex Programming Method for Image Reconstruction
Authors: Johnathan M. Bardsley, Curtis R. Vogel
Venue: SIAM Journal on Scientific Computing (2003)

We consider a large-scale convex minimization problem with nonnegativity constraints that arises in astronomical imaging. We develop a cost functional which incorporates the statistics of the noise in the image data and Tikhonov regularization to induce stability. We introduce an efficient hybrid gradient projection-reduced Newton (active set) method. By "reduced Newton" we mean taking Newton steps only in the inactive variables. Due to the large size of our problem, we compute approximate reduced Newton steps using conjugate gradient (CG) iteration. We also introduce a highly effective sparse preconditioner that dramatically speeds up CG convergence. A numerical comparison between our method and other standard large-scale constrained minimization algorithms is presented.
On the solvability of the Birkhoff interpolation problem
Authors: J. Rubió, J. L. Díaz-Barrero, P. Rubió
Venue: Journal of Approximation Theory (2003)

A univariate Birkhoff interpolation problem is considered and the smallest N, namely oN, for which the Birkhoff interpolation problem is always solvable is given. In particular, for Pólya matrices E with n ones we obtain oN ≤ n + p, where p is the number of odd supported sequences in E, and show that the preceding bound is the best possible.
Parallelization of divide-and-conquer by translation to nested loops
Authors: Christoph A. Herrmann, Christian Lengauer
Venue: Journal of Functional Programming (1999)

We present a hierarchical classification of specializations of the divide-and-conquer paradigm. The aim is to identify a subclass of divide-and-conquer algorithms with an efficient parallel implementation which can be viewed as a static space-time mapping. The specializations impose a balanced call tree, a fixed degree of the problem division, and elementwise operations. The correctness of our compile-time transformations is proved by equational reasoning in Haskell; recursion and iteration are handled by induction. We demonstrate the practicality of the skeleton by some examples, one of which is Strassen's matrix multiplication.
Fresnel zone and reflectarray antennas for space missions: concepts, computational techniques and characterizations
Authors: Behrouz Khayatian
Venue:  (2003)

Reflector antennas generally employ parabolic shaped main reflectors and have found a wide range of applications for both earth stations and satellite systems. Increasingly, one may find many advantages in minimizing antenna shaping requirement and weight as well as more compact designs by employing flat reflectors (either on the main reflector or on the subreflector) which can achieve a desired set of criteria for antenna performance. Two electrically large antennas which use flat min reflectors are Fresnel Zone (FZ) and reflectarray antennas which are being addressed in this dissertation. Analytical techniques are proposed, implemented, and verified to analyze these reflector geometries. A two dimensional (2-D) multi-scatterer analysis is formulated and implemented using various electromagnetic scattering techniques such as Physical Optics (PO), Method of Moments (MoM), and Geometrical Theory of Diffraction (GTD). The capability of the 2-D technique is further extended for dual reflector analysis with flat subreflector panels as well as design and analysis of FZ antennas with a proposed space missions application in solar sailing. FZ antenna design is based on establishing regions of quasi-uniform phases according to the PO current on the reflector face. The concepts extracted from the 2-D analysis of FZ reflectors is carried to the three dimensional (3-D) cases and incorporated into a multi reflector code, which has been widely used in variety of reflector applications. Like FZ antennas, reflectarrays work according to a similar set of principals by achieving a uniform phase current on the flat reflectarray surface. Accordingly, an analytical methodology is proposed and implemented within the structure of the multi-reflector code to analyze and give design criteria for both single and dual reflectarray configurations. This technique is compared to measured results published for single reflectarrays and is investigated for near-field Gregorian reflectarrays with beam scanning capabilities.
Low-k dielectrics: a non-destructive characterization by infrared spectroscopic ellipsometry
Authors: P. Boher, C. Defranoux, M. Bucchia, C. Guillotin
Venue: Microelectronic Engineering (2003)

An infrared spectroscopic ellipsometer devoted to the characterization of silicon microelectronics has recently been developed at SOPRA. Its main feature is the ability to measure on a small spot (80×200 µm) with a high signal/noise ratio. An original patented optical design suppresses back face reflection and ensures good-quality spectral measurements in the 600-7000 cm-1 range. The excellent signal/noise ratio allows the performance of measurements in less than 30 s. Automation and real-time analysis are included to offer an operator-orientated metrology tool. Details of the instrument are presented, and its use for the characterization of different kinds of low-k dielectrics.
An approach to secure information flow on Object Oriented Role-based Access Control model
Authors: Cungang Yang, Chang N. Zhang
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

In this paper, we conclude that confinement problem may occur on the Object Oriented Role-based Access Control model (ORBAC). In order to solve the problem, a technique called information flow analysis is proposed. Moreover, based on the information flow technique and the principle of mandatory access control principles, a message filtering algorithm and a role set assignment method are developed to deal with the confinement problem on ORBAC.