ppxscal/embedding_network huggingface dataset:
An Algebraic Substructuring Method for Large-Scale Eigenvalue Calculation
Authors: Chao Yang, Weiguo Gao, Zhaojun Bai, Xiaoye S. Li, Lie-Quan Lee, Parry Husbands, Esmond Ng
Venue: SIAM Journal on Scientific Computing (2005)

This paper is concerned with solving large-scale eigenvalue problems by algebraic substructuring. Algebraic substructuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. Through an algebraic analysis, we identify critical conditions under which a simple version of algebraic substructuring works well. This particular version of substructuring is identical to the component mode synthesis (CMS) method (see [R. R. Craig and M. C. C. Bampton, {\em Coupling of substructures for dynamic analysis}, AIAA J., 6 (1968), pp. 1313--1319] and [W. C. Hurty, {\em Vibrations of structure systems by component-mode synthesis}, J. Engrg. Mech., 86 (1960), pp. 51--69]) when the matrix reordering is based on a geometric partitioning of the computational domain. We observe an interesting connection between the accuracy of an approximate eigenpair obtained through substructuring and the distribution of the components of eigenvectors of a canonical matrix pencil congruent to the original problem. A priori error bounds for the smallest eigenpair approximation are developed. This development leads to a simple heuristic for choosing spectral components (modes) from each substructure. The effectiveness of such a heuristic is demonstrated with numerical examples. We show that algebraic substructuring can be effectively used to solve a generalized eigenvalue problem arising from the finite element analysis of an accelerator structure.
The processes of learning in a computer algebra system (cas) environment for college students learning calculus
Authors: Douglas T. Owens, Rick Voithofer
Venue:  (2005)

This study is a qualitative case study focusing on the question &ldquo;What are the processes of learning in a Computer Algebra System (CAS) environment for college students learning calculus?&rdquo; The study is designed to research the impact on student learning of new and revolutionary software available for mathematics education. Research in CAS has focused on outcome-based studies and more philosophical work on the curriculum and assessment implications of CAS. Missing are studies which look at what exactly happens when students try to learn mathematics in a CAS environment: What does CAS learning look like on a day-to-day basis? and What does CAS learning look like across the period of a ten-week course? The importance of investigating these processes lies in understanding the impact of CAS on learning so that an appropriate balance can be found in the integration of technology into teaching ensuring that the merits of traditional methods are not lost and that the merits and demerits of CAS use are fully understood. The primary data for the study consists of audio and video of tape of a group of students in a college course learning calculus using CAS software. This data was supplemented by interviews with the students as well as analysis of the students' homework and tests. Analysis of the data via Rotman Model of Mathematical Understanding provides a lens through which to view the place of technology in the CAS classroom and through which to view the journey of each student across the quarter. The Pirie-Kieren Model for the Growth of Mathematical Understanding is then mobilised as a lens through which to examine specific learning episodes as they occur in the classroom. As well as providing examples of student learning, the broader conclusions of the study are (i) that the framing and introduction of technology at the beginning of an instruction period impacts crucially on student behaviour and use of technology throughout that period and (ii) that while students will naturally experiment in a CAS environment intervention is probably required for them to develop sophistication in their experimental behaviour and strategies.
Orthogonal Transforms in Bases of Slant Step Functions. II. Methods of Generating Orthogonal Slant Transforms with Fast Algorithms for Image Coding and Compression
Authors: L. A. Gnativ
Venue: Cybernetics and Systems Analysis (2005)

Recurrent matrix methods and methods based on the Walsh transform and rotation matrices generating orthogonal slant transforms of high and low correlation are proposed. These methods are used to develop efficient fast slant-transform algorithms without multiplication and additional permutations of output data.
A comparison on two techniques for collecting statistics in simulation
Authors: Boo Ho Rho
Venue: ACM SIGSIM Simulation Digest (1977)

The purpose of the paper is to compare two techniques of collecting statistics: The method of batch means and the regenerative process method. The compairsons are in terms of accuracy and precision of sample performance measurements and exexution time.Two different queuing systems of M/M/1 and M/M/4 with traffic intensity factors of 0.1, 0.5, and 0.9 are designed for experimentation. The results indicate that the regenerative method in general shows better performance than the method of batch means.
L1-Optimal Nonparametric Frontier Estimation via Linear Programming
Authors: S. Girard, A. Iouditski, A. V. Nazin
Venue: Automation and Remote Control (2005)

A frontier estimation method for a set of points on a plane is proposed, being optimal in L 1-norm on a given class of β-Holder boundary functions under β ¿ (0, 1]. The estimator is defined as sufficiently regular linear combination of kernel functions centered in the sample points, which covers all these points and whose associated support is of minimal surface. The linear combination weights are calculated via solution of the related linear programming problem. The L 1-norm of the estimation error is demonstrated to be convergent to zero with probability one, with the optimal rate of convergence.
N&eacute;gociation entre agents au sein de r&eacute;seaux ad-hoc
Authors: Cosmin Carabelea, Michael Berger
Venue: Proceedings of the 2nd French-speaking conference on Mobility and ubiquity computing (2005)

In the last years the multi-agent paradigm has emerged as a suitable solution to the challenges of electronic commerce (e-commerce) applications. However, new problems arise in mobile-commerce scenarios, where agents negotiating on behalf of their users are deployed on mobile devices. Negotiation is a time-constraint process and it might be difficult to realize applications in ad-hoc networks. In this paper we investigate the means to deploy agents negotiating on handheld devices in ad-hoc networks. We implemented a test application called ADvertising on MObile Phones (ADOMO) where an agent executed on a handheld device negotiates and establishes contracts with commercial agents in its neighborhood. The objects of the negotiations and contracts are commercial advertisements (ads) to be displayed on the device's screen in exchange for a small fee / benefit. First, we describe an implementation of this application and obtained results. In the second part we show modifications to the system in order to enable the creation of contracts in a shorter time. The agents were deployed on both a PocketPC and a smart phone.
An Efficient and Secure Peer-to-Peer Overlay Network
Authors: Honghao Wang, Yingwu Zhu, Yiming Hu
Venue: Proceedings of the The IEEE Conference on Local Computer Networks 30th Anniversary (2005)

Most of structured P2P overlays exploit Distributed Hash Table (DHT) to achieve an administration-free, fault tolerant overlay network and guarantee to deliver a message to the destination within O(logN) hops.While elegant from a theoretical perspective, those systems face diffi- culties under an open environment. Not only frequently joining and leaving of nodes generate enormous maintenance overhead, but also various behaviors and resources of peers compromise overlay performance and security. Instead of building P2P overlay from the theoretical view, this paper builds the overlay network from the perspective of the physical network. By combining different network topology-aware techniques, a distinctive overlay network that closely matches the Internet topology is constructed. The P2P system based on this structure is not only highly efficient for routing, but also keeps maintenance overhead very low even under highly dynamic environment. Moreover, the system provides a new aspect to solve many security issues.
Range Nearest-Neighbor Query
Authors: Haibo Hu, Dik Lun Lee
Venue: IEEE Transactions on Knowledge and Data Engineering (2006)

A range nearest-neighbor (RNN) query retrieves the nearest neighbor (NN) for every point in a range. It is a natural generalization of point and continuous nearest-neighbor queries and has many applications. In this paper, we consider the ranges as (hyper)rectangles and propose efficient in-memory processing and secondary memory pruning techniques for RNN queries in both 2D and high-dimensional spaces. These techniques are generalized for kRNN queries, which return the k nearest neighbors for every point in the range. In addition, we devise an auxiliary solution-based index EXO-tree to speed up any type of NN query. EXO-tree is orthogonal to any existing NN processing algorithm and, thus, can be transparently integrated. An extensive empirical study was conducted to evaluate the CPU and I/O performance of these techniques, and the study showed that they are efficient and robust under various data sets, query ranges, numbers of nearest neighbors, dimensions, and cache sizes.
A Qualitative Treatment of Spatial Data
Authors: Takao Sumitomo, Kazuko Takahashi
Venue: Proceedings of the 17th IEEE International Conference on Tools with Artificial Intelligence (2005)

This paper aims at an efficient treatment of spatial data by qualitative representation. We propose a new framework called PLCA, which provides a symbolic representation for the figure in two-dimensional plane, that focuses on the connections between regions. It is based on the simple objects: points (P), lines (L), circuits (C) and areas (A). The entire figure is represented as a combination of these objects. Pairs of areas, circuits or lines never cross. The simple, clear data structure based on objects makes the system easy to implement and feasible. For a figure that consists of a set of regions in two-dimensional plane, there exists a corresponding consistent PLCA expression. For a consistent PLCA expression, there is a unique figure in two-dimensional plane in the sense of connection pattern, if there exists. Topological reasoning can be performed on a PLCA expression, such as judging the connection patterns of areas. We define the operations of area integration and area division on a PLCA expression. These operations preserve the consistency of the expression, and they correspond to the real actions on figures. We can add attributes to each object, such as the properties that hold on an area or that an object stands for, and make an attributed PLCA. The operations of area integration/divisionon an attributed PLCA corresponds to the alteration of the classification level of objects. Semantic spatial reasoning can be performed on an attributed PLCA.
Parallel Parameter Tuning for Applications with Performance Variability
Authors: Vahid Tabatabaee, Ananta Tiwari, Jeffrey K. Hollingsworth
Venue: Proceedings of the 2005 ACM/IEEE conference on Supercomputing (2005)

In this paper, we present parallel on-line optimization algorithms for parameter tuning of parallel programs. We employ direct search algorithms that update parameters based on real-time performance measurements. We discuss the impact of performance variability on the accuracy and efficiency of the optimization algorithms and proposed modified versions of the direct search algorithms to cope with it. The modified version uses multiple samples instead of single sample to estimate the performance more accurately.We present preliminary results that the performance variability of applications on clusters is heavy tailed. Finally, we studay and demonstrate the performance ofthe proposed algorithms for real scientific application.
A Fast Noniterative Scheduler for Input-Queued Switches with Unbuffered Crossbars
Authors: Kevin F. Chen, Edwin H. -M. Sha, S. Q. Zheng
Venue: Proceedings of the 8th International Symposium on Parallel Architectures,Algorithms and Networks (2005)

Most high-end switches use an input-queued or a combined input- and output-queued architecture. The switch fabrics of these architectures commonly use an iterative scheduling system such as iSLIP. Iterative schedulers are not very scalable and can be slow. We propose and study a new fabric scheduling scheme that is fast and scalable. This scheduler finds maximum matching in a single iteration. It provides full throughput and incurs very low delay. It is fair and of low complexity. It greatly outperforms traditional iterative schedulers. It also renders arbitration egress memory unnecessary. Its only drawback is that it requires the support of several reads to an input memory at the same time. But simulations show this drawback is immaterial as read multiplicity is very low in various traffic conditions.
LiXQuery: a formal foundation for XQuery research
Authors: Jan Hidders, Philippe Michiels, Jan Paredaens, Roel Vercammen
Venue: ACM SIGMOD Record (2005)

XQuery is considered to become the standard query language for XML documents. However, the complete XQuery syntax and semantics seem too complicated for research and educational purposes. By defining a concise backwards compatible subset of XQuery with a complete formal description, we provide a practical foundation for XQuery research. We pay special attention to usability by supporting the most typical XQuery expressions.
MultiSpace: Enabling Electronic Document Micro-mobility in Table-Centric, Multi-Device Environments
Authors: Katherine Everitt, Chia Shen, Kathy Ryall, Clifton Forlines
Venue: Proceedings of the First IEEE International Workshop on Horizontal Interactive Human-Computer Systems (2006)

Although electronic media has changed how people interact with documents, today's electronic documents and the environments in which they are used are still impoverished relative to traditional paper documents when used by groups of people and across multiple computing devices. Vertical interfaces (e.g., walls and monitors) afford a less democratic style of interaction than generally observed when people are working around a table. In this paper, we introduce MultiSpace, a research effort which explores the role of the table as a central hub to support ad hoc collaboration in a multi-device environment. The table-centric approach offers new interaction techniques to provide egalitarian access and shared transport of data, supporting mobility and micromobility [11] of electronic content between tables and other devices. Our observations show how people use these techniques, and how tabletop technology can support and augment collaborative tasks.
Groovy Service: On-Demand Web Service by Script Language
Authors: Zhen Chun, Chuan He
Venue: Proceedings of the IEEE International Workshop (2005)

The improvement of web service is eager for the design and implementation of on-demand service with high performance and low overhead. In this paper, the implementation strategies of On- Demand Service are listed and analyzed first. Then, the architecture of on-demand service is purposed, and the Groovy script language that is intelligent and powerful is chosen for the service specification language. Furthermore, the Groovy based on-demand service, which is named Groovy service, is designed and implemented based on Java language and the famous open source service container Tomcat/Axis. At last, the test shows that Groovy can make the service architecture more flexible and powerful without heavy overhead.
Strategy hubs: Domain portals to help find comprehensive information
Authors: Suresh K. Bhavnani, Christopher K. Bichakjian, Timothy M. Johnson, Roderick J. Little, Frederick A. Peck, Jennifer L. Schwartz, Victor J. Strecher
Venue: Journal of the American Society for Information Science and Technology (2006)

Recent studies suggest that the wide variability in type, detail, and reliability of online information motivate expert searchers to develop procedural search knowledge. In contrast to prior research that has focused on finding relevant sources, procedural search knowledge focuses on how to order multiple relevant sources with the goal of retrieving comprehensive information. Because such procedural search knowledge is neither spontaneously inferred from the results of search engines, nor from the categories provided by domain-specific portals, the lack of such knowledge leads most novice searchers to retrieve incomplete information. In domains like healthcare, such incomplete information can lead to dangerous consequences. To address the above problem, a new kind of domain portal called a Strategy Hub was developed and tested. Strategy Hubs provide critical search procedures and associated high-quality links to enable users to find comprehensive and accurate information. We begin by describing how we collaborated with physicians to systematically identify generalizable search procedures to find comprehensive information about a disease, and how these search procedures were made available through the Strategy Hub. A controlled experiment suggests that this approach can improve the ability of novice searchers in finding comprehensive and accurate information, when compared to general-purpose search engines and domain-specific portals. We conclude with insights on how to refine and automate the Strategy Hub design, with the ultimate goal of helping users find more comprehensive information when searching in unfamiliar domains. &copy; 2006 Wiley Periodicals, Inc.
Fast Approximate Search in Large Dictionaries
Authors: Stoyan Mihov, Klaus U. Schulz
Venue: Computational Linguistics (2004)

The need to correct garbled strings arises in many areas of natural language processing. If a dictionary is available that covers all possible input tokens, a natural set of candidates for correcting an erroneous input P is the set of all words in the dictionary for which the Levenshtein distance to P does not exceed a given (small) bound k. In this article we describe methods for efficiently selecting such candidate sets. After introducing as a starting point a basic correction method based on the concept of a "universal Levenshtein automaton," we show how two filtering methods known from the field of approximate text search can be used to improve the basic procedure in a significant way. The first method, which uses standard dictionaries plus dictionaries with reversed words, leads to very short correction times for most classes of input strings. Our evaluation results demonstrate that correction times for fixed-distance bounds depend on the expected number of correction candidates, which decreases for longer input words. Similarly the choice of an optimal filtering method depends on the length of the input words.
Incorporating Error Detection and Online Reconfiguration into a Regular Architecture for the Advanced Encryption Standard
Authors: L. Breveglieri, I. Koren, P. Maistri
Venue: Proceedings of the 20th IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems (2005)

Fault injection based attacks on cryptographic devices aim at recovering the secret keys by inducing an error in the computation process. They are now considered a real threat and countermeasures against them must be taken. In this paper, we describe an extension to an existing AES architecture proposed by Mangard et al. [13], which provides error detection and fault tolerance by exploiting the high regularity of the architecture. The proposed design is capable of performing online error detection and reconfiguring internal data paths to protect against faults occurring in the computation process. We also describe how different redundancy levels provide protection against different numbers of errors. The presented design incorporating fault detection and tolerance has the same throughput as the base architecture but incurs a non-negligible area overhead. This overhead is about 40% for the fault detection circuitry and 134% for the entire fault detection and tolerance (through reconfiguration). Although quite high, this overhead is still lower than for reference solutions such as duplication (providing detection) and triple modular redundancy (providing fault masking).
Core Points - A Framework For Structural Parameterization
Authors: Jakob Sternby, Anders Ericsson
Venue: Proceedings of the Eighth International Conference on Document Analysis and Recognition (2005)

Most implementations of single character recognition use standard arclength parameterization of the handwritten samples. A problem with the arclength approach is that points on curves of different samples from one character class may then actually correspond to parts of different structural significance. Many methods such as DTW and HMMhave been successful partly because they are less sensitive to parameterizational differences. Given a sufficiently fine decomposition of a character sample into smaller segments, the complex non-linear variations of handwritten data can be viewed as a set of local linear transformations of the segments. In this paper we present a parameterization technique that implicitly defines such a structural decomposition. Experiments reveal that recognition rates for kNN template matching increase for reparameterized samples thus proving that the new parameterization removes redundance in a way that is genuinely beneficial for discrimination purposes. In addition to these quantitive results, visual inspection of the modes of singular value decomposition of reparameterized samples show that the new parameterization reduces the impact of parameterizational differences in shape variations of character samples.
A Strategy of Load Balancing in Object Storage System
Authors: Lingfang Zeng, Dan Feng, Fang Wang, Ke Zhou
Venue: Proceedings of the The Fifth International Conference on Computer and Information Technology (2005)

Most of traditional load balancing strategies are based on servers or applications architecture. Storage subsystem, as the back tier, provides file or block interface to server or application tier, is often ignored when the bottleneck of service is studied. Our load balancing strategy is based on storage object which provides object interface for the up tier. We concentrate on storage objects with massive dynamic processing. The characteristics of storage object in object storage system (OSS) enable us to apply our load balancing strategy at the back end of servers or applications in order to deal with bottlenecks at the storage tier in data-intensive applications.
On the need for humane rationing of interactive service
Authors: Francis M. Sim, Roscoe T. Miller, Glen D. Kreider
Venue: ACM SIGSOC Bulletin (1982)

In a sense, our text for the next few pages is that "the meek <u>should</u> inherit . . . "; or, at least, if they don't get the whole earth, they deserve a fair shake in computing. Hopefully, the title we've chosen is self-explanatory; but if there were to be a subtitle, perhaps we'd choose, "A Funny Thing Happened on the Way to Interactive Computing."
Relational Learning techniques for Document Image Understanding: Comparing Statistical and Logical approaches
Authors: Michelangelo Ceci, Margherita Berardi, Donato Malerba
Venue: Proceedings of the Eighth International Conference on Document Analysis and Recognition (2005)

In this paper, we evaluate and systematically compare two different (multi-)relational learning methods based on a statistical approach and a logical approach for the task of document image understanding. For a fair comparison, both methods are tested on the same real world dataset consisting of multipage articles published in an international journal. An analysis of pros and cons of both approaches is reported.