ppxscal/embedding_network huggingface dataset:
Implementation of a diagnostic and troubleshooting multi-agent system for cellular networks
Authors: Mahamat Guiagoussou, Said Soulhi
Venue: International Journal of Network Management (1999)

This article presents the implementation of a maintenance application for cellular switching system using the multi-agent paradigm. The main philosophy behind the design of the multi-agent system is based on the TMN framework, where each agent can mapped with one or several TMN functional blocks. Copyright &copy; 1999 John Wiley Sons, Ltd.
Are Edges Incomplete?
Authors: James H. Elder
Venue: International Journal of Computer Vision (1999)

We address the problem of computing a general-purpose early visual representation that satisfies two criteria. 1) Explicitness: To be more useful than the original pixel array, the representation must take a significant step toward making important image structure explicit. 2) Completeness: To support a diverse set of high-level tasks, the representation must not discard information of potential perceptual relevance. The most prevalent representation in image processing and computer vision that satisfies the completeness criterion is the wavelet code. In this paper, we propose a very different code which represents the location of each edge and the magnitude and blur scale of the underlying intensity change. By making edge structure explicit, we argue that this representation better satisfies the first criterion than do wavelet codes. To address the second criterion, we study the question of how much visual information is lost in the representation. We report a novel method for inverting the edge code to reconstruct a perceptually accurate estimate of the original image, and thus demonstrate that the proposed representation embodies virtually all of the perceptually relevant information contained in a natural image. This result bears on recent claims that edge representations do not contain all of the information needed for higher level tasks.
HOPs and COPs: Room frames with partitionable transversals
Authors: J. H. Dinitz, E. R. Lamken
Venue: Designs, Codes and Cryptography (2000)

In this paper, we construct Room frames with partitionable transversals. Direct and recursive constructions are used to find sets of disjoint complete ordered partitionable (COP) transversals and sets of disjoint holey ordered partitionable (HOP) transversals for Room frames. Our main results include upper and lower bounds on the number of disjoint COP transversals and the number of disjoint HOP transversals for Room frames of type 2^n. This work is motivated by the large number of applications of these designs.
A BLAS-3 Version of the QR Factorization with Column Pivoting
Authors: Gregorio Quintana-Ortí, Xiaobai Sun, Christian H. Bischof
Venue: SIAM Journal on Scientific Computing (1998)

The QR factorization with column pivoting (QRP), originally suggested by Golub [Numer. Math., 7 (1965), 206--216], is a popular approach to computing rank-revealing factorizations. Using Level 1 BLAS, it was implemented in LINPACK, and, using Level 2 BLAS, in LAPACK. While the Level 2 BLAS version delivers superior performance in general, it may result in worse performance for large matrix sizes due to cache effects. We introduce a modification of the QRP algorithm which allows the use of Level 3 BLAS kernels while maintaining the numerical behavior of the LINPACK and LAPACK implementations. Experimental comparisons of this approach with the LINPACK and LAPACK implementations on IBM RS/6000, SGI R8000, and DEC AXP platforms show considerable performance improvements.
Quasi-Synchronous Checkpointing: Models, Characterization, and Classification
Authors: D. Manivannan, Mukesh Singhal
Venue: IEEE Transactions on Parallel and Distributed Systems (1999)

Checkpointing algorithms are classified as synchronous and asynchronous in the literature. In synchronous checkpointing, processes synchronize their checkpointing activities so that a globally consistent set of checkpoints is always maintained in the system. Synchronizing checkpointing activity involves message overhead and process execution may have to be suspended during the checkpointing coordination, resulting in performance degradation. In asynchronous checkpointing, processes take checkpoints without any coordination with others. Asynchronous checkpointing provides maximum autonomy for processes to take checkpoints; however, some of the checkpoints taken may not lie on any consistent global checkpoint, thus making the checkpointing efforts useless. Asynchronous checkpointing algorithms in the literature can reduce the number of useless checkpoints by making processes take communication induced checkpoints besides asynchronous checkpoints. We call such algorithms quasi-synchronous. In this paper, we present a theoretical framework for characterizing and classifying such algorithms. The theory not only helps to classify and characterize the quasi-synchronous checkpointing algorithms, but also helps to analyze the properties and limitations of the algorithms belonging to each class. It also provides guidelinesfor designing and evaluating such algorithms.
Finite Element Approximations to the System of Shallow Water Equations, Part II: Discrete-Time A Priori Error Estimates
Authors: S. Chippada, C. N. Dawson, M. L. Mart
Venue: SIAM Journal on Numerical Analysis (1998)

Various sophisticated finite element models for surface water flow exist in the literature. Gray, Kolar, Luettich, Lynch, and Westerink have developed a hydrodynamic model based on the generalized wave continuity equation (GWCE) formulation and have formulated a Galerkin finite element procedure based on combining the GWCE with the nonconservative momentum equations. Numerical experiments suggest that this method is robust and accurate and suppresses spurious oscillations which plague other models. In this paper, we analyze a closely related Galerkin method which uses the conservative momentum equations (CME). For this GWCE--CME system of equations, we present, for discrete time, an a priori error estimate based on an ${\cal L}^{2}$ projection.
Confessions of a gardener: a review of information ecologies
Authors: William Hart-Davidson
Venue: ACM Journal of Computer Documentation (JCD) (2000)

This review of Information Ecologies places the text in the mediating tradition that seeks a middle ground between rigid technological determinism and indifferent value neutrality. The biological metaphors for situated technology use make interesting reading,but the stories may not be compelling evidence that users really can shape technological change from the local level.
Modeling mobile IP in mobile UNITY
Authors: Peter J. McCann, Gruia-Catalin Roman
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (1999)

With recent advances in wireless communication technology, mobile computing is an increasingly important area of research. A mobile system is one where independently executing components may migrate through some space during the course of the computation, and where the pattern of connectivity among the components changes as they move in and out of proximity. Mobile UNITY is a notation and proof logic for specifying and reasoning about mobile systems. In this article it is argued that Mobile UNITY contributes to the modular development of system specifications because of the declarative fashion in which coordination among components is specified. The packet-fowarding mechanism at the core of the Mobile IP protocol for routing to mobile hosts is taken as an example. A Mobile UNITY model of packet forwarding and the mobile system in which it must operate is developed. Proofs of correctness properties, including important real-time properties, are outlined, and the role of formal verification in the development of protocols such as Mobile IP is discussed.
Locating Corruptions in a Replicated File in a Distributed Environment
Authors: Ada Waichee Fu, Siu-Cheung Chau
Venue: The Journal of Supercomputing (1999)

When a data file is replicated at more than one site, it is of interest to detect corruption by comparing the multiple copies. In order to reduce the amount of messaging for large files, techniques based on page signatures and combined signatures have been explored. However, for 3 or more sites, the known methods assume that the number of corrupted page copies is at most &lfloor;M/2&rfloor; &minus; 1, where M is the number of sites. This is a pessimistic assumption which is unrealistic. In this paper, this assumption is replaced by another assumption which is shown to be reasonable. Based on this assumption, and based on a finer model of the system, three distributed algorithms are derived, which can either improve the performance or provide more tolerance to corruptions compared to previous methods. As in some previous work, the amount of signature transmission in the algorithms varies according to the number and patterns of page copy corruptions that actually occur, and two of the algorithms achieve the optimal amount of signature transmission when no failure occurs.
Management of international networks
Authors: Floris van den Broek, Maarten Looijen
Venue: International Journal of Network Management (1997)

This article outlines particularities which must be addressed when building, controlling and maintaining international networks. &copy; 1997 John Wiley & Sons, Ltd.
A fast and accurate iterative solution of a multi-class threshold-based queueing system with hysteresis
Authors: Leana Golubchik, John C. S. Lui
Venue: ACM SIGMETRICS Performance Evaluation Review (2000)

Our main goal in this work is to develop an efficient method for solving such models and computing the corresponding performance measures of interest, which can subsequently be used in evaluating designs of threshold-based systems.
Fixed-point query languages for linear constraint databases
Authors: Stephan Kreutzer
Venue: Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2000)

We introduce a family of query languages for linear constraint databases over the reals. The languages are defined over two-sorted structures, the first sort being the real numbers and the second sort consisting of a decomposition of the input relation into regions. The languages are defined as extensions of first-order logic by transitive closure or fixed-point operators, where the fixed-point operators are defined over the set of regions only. It is shown that the query languages capture precisely the queries definable in various standard complexity classes including PTIME.
Synthesis of Application Specific Instructions for Embedded DSP Software
Authors: Hoon Choi, Jong-Sun Kim, Chi-Won Yoon, In-Cheol Park, Seung Ho Hwang, Chong-Min Kyung
Venue: IEEE Transactions on Computers (1999)

Application specific instructions play an important role in reducing the required code size and increasing performance in embedded DSP systems. This paper describes a new approach to generate application specific instructions for DSP applications. The proposed approach is based on a modified subset-sum problem and supports multicycle complex instructions, as well as single-cycle instructions, while the previous state-of-the-art approaches generate only the single-cycle instructions or just select instructions from the fixed super-set of possible instructions. In addition, the proposed approach can also be applied to the case that instructions are predefined. Experimental results on real applications show that various given constraints can be met by the generated set of application specific instructions without attaching special hardware accelerators.
A survey of components for intelligent tutoring pedagogical aspects of GET-BITS model
Authors: Ljubomir Jerinic, Vladan Devedzic
Venue: ACM SIGCUE Outlook (1999)

The concept of software components has received relatively little attention so far by the researchers in the field of Artificial Intelligence in Education (AIED). This paper is an attempt to bring more light on this important concept and to describe the benefits that component-based Intelligent Tutoring Systems (ITSs) can bring to the field. Surprisingly enough, there is still no consensus on the notion of component among AIED researchers. There are many open questions and unclear issues. By carefully structuring the description of software components in general, as well as by showing some examples of components for ITSs design, the paper presents several important related issues, like functionality of components, their granularity, generality, interoperability, and reusability. Special attention is given to the architectural and communication considerations, as well as to the relation between components and ontology's for ITSs design. The paper describes pedagogical aspects and the control knowledge of the component based model of intelligent tutoring systems, called GET-BITS. The focus is on class hierarchies and design of classes for representing the pedagogical and the control knowledge in the GET-BITS model. Distinction has been made between different modes of operation of the pedagogical module in an intelligent tutoring system (teaching, examination, and consulting), resulting in the necessity for the class hierarchies to reflect specific pedagogical knowledge structure.
The Compactness of Interval Routing
Authors: Cyril Gavoille, David Peleg
Venue: SIAM Journal on Discrete Mathematics (1999)

The compactness of a graph measures the space complexity of its shortest path routing tables. Each outgoing edge of a node x is assigned a (pairwise disjoint) set of addresses, such that the unique outgoing edge containing the address of a node y is the first edge of a shortest path from x to y. The complexity measure used in the context of interval routing is the minimum number of intervals of consecutive addresses needed to represent each such set, minimized over all possible choices of addresses and all choices of shortest paths. This paper establishes asymptotically tight bounds of n/4 on the compactness of an n-node graph. More specifically, it is shown that every n-node graph has compactness at most n/4+o(n), and conversely, there exists an n-node graph whose compactness is n/4 - o(n). Both bounds improve upon known results. (A preliminary version of the lower bound has been partially published in Proceedings of the 22nd International Symposium on Mathematical Foundations of Computer Science, Lecture Notes in Comput. Sci. 1300, pp. 259--268, 1997.)
curlybot: designing a new class of computational toys
Authors: Phil Frei, Victor Su, Bakhtiar Mikhak, Hiroshi Ishii
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2000)

We introduce an educational toy, called curlybot, as the basis for a new class of toys aimed at children in their early stages of development &mdash; ages four and up. curlybot is an autonomous two-wheeled vehicle with embedded electronics that can record how it has been moved on any flat surface and then play back that motion accurately and repeatedly. Children can use curlybot to develop intuitions for advanced mathematical and computational concepts, like differential geometry, through play away from a traditional computer. In our preliminary studies, we found that children learn to use curlybot quickly. They readily establish an affective and body syntonic connection with curlybot, because of its ability to remember all of the intricacies of their original gesture; every pause, acceleration, and even the shaking in their hand is recorded. Programming by example in this context makes the educational ideas implicit in the design of curlybot accessible to young children.
An empirical validation of a contingency model for information require-ments determination
Authors: Mohammed El Louadi, Dennis F. Galletta, Jeffrey L. Sampler
Venue: ACM SIGMIS Database (1998)

A contingency model for system development was subjected to several conceptual and operational adjustments and empirical tests. According to the model, there should be a degree of fit between development project uncertainty and the strategy for determining information requirements, ranging from accepting initial requirements statements to experimenting with prototypes to discover requirements. This study introduced a new IRD strategy construct that focused on the extent of interaction between users and developers. The study also differentiated between perceptual and evidential outcomes, between process and product outcomes, and between users' and developers' points of view. The hypotheses predicted that the degree of fit between project uncertainty and the IRD strategy would account for perceptual and evidential project outcomes from both the user's and developer's points of view. Results indicated that only by relying on the new extent of interaction construct, was support found. From the developers' standpoint, the degree of fit appeared to be related to perceptual assessments of the process and product. From the user's standpoint, the degree of fit was only related to perceptual assessments of the process. There was no support for the hypothesized impact of fit on evidential outcomes.
Problem Based Learning as a Curricular Strategy for Medical Undergraduates: A Tutor's Experience
Authors: Kalpana Luthra, Nibhriti Das
Venue: Journal of Medical Systems (1998)

This article focuses on the experiences and role of a tutor while conducting a problem based learning (PBL) exercise to facilitate the learning of biochemistry and molecular biology. A case presentation of sickle cell anemia was used to frame a module. The objective of this experimental exercise was to assess the suitability and effectiveness of problem based learning in the first year of undergraduate medical course and to practice self-assessment by tutors in this new role of a facilitator of learning through small group discussion. A tutor during such a learning session encouraged the students to apply their reasoning to analyze the problem and to develop self-directed learning skills in acquiring the knowledge appropriate to their perceived needs to work on a problem. The tutors ensured that they apply this knowledge in their work with other similar problems that they would encounter later in life.
On bounding time and space for multiprocessor garbage collection
Authors: Guy E. Blelloch, Perry Cheng
Venue: ACM SIGPLAN Notices (1999)

This paper presents the first multiprocessor garbage collection algorithm with provable bounds on time and space. The algorithm is a real-time shared-memory copying collector. We prove that the algorithm requires at most 2(R(l + 2/k) + N + 5PD) memory locations, where P is the number of processors, R is the maximum reachable space during a computation (number of locations accessible from the root set), N is the maximum number of reachable objects, D is the maximum depth of any data object, and k is a parameter specifying how many locations are copied each time a location is allocated. Furthermore we show that client threads are never stopped for more than time proportional to k non-blocking machine instructions. The bounds are guaranteed even with arbitrary length arrays. The collector only requires write-barriers (reads are unaffected by the collector), makes few assumptions about the threads that are generating the garbage, and allows them to run mostly asynchronously.
A Fast Poisson Solver for the Finite Difference Solution of the Incompressible Navier--Stokes Equations
Authors: Gene H. Golub, Lan Chieh Huang, Horst Simon, Wei-Pai Tang
Venue: SIAM Journal on Scientific Computing (1998)

In this paper, a fast direct solver for the Poisson equation on the half-staggered grid is presented. The Poisson equation results from the projection method of the finite difference solution of the incompressible Navier--Stokes equations. To achieve our goal, new algorithms for diagonalizing a semidefinite pair are developed. The fast solver can also be extended to the three-dimensional case. The motivation and related issues in using this half-staggered grid are also discussed.
Configuring a Network Management System for Efficient Operation
Authors: Kohei Haj Ohta, Nei Haj Kato, Glenn Haj Mansfield, Yoshiaki Haj Nemoto
Venue: International Journal of Network Management (1996)

Configuring a network management system involves the delicate art of balancing the requirements of the management system with the available network resources.
Writing and editing complexity theory: tales and tools
Authors: Lane A. Hemaspaandra, Alan L. Selman
Venue: ACM SIGACT News (1998)

Each researcher should have a full shelf---physical or virtual---of books on writing and editing prose. Though we make no claim to any special degree of expertise, we recently edited a book of complexity theory surveys [HS97], and in doing so we were brought into particularly close contact with the subject of this article, and with a number of the excellent resources available to writers and editors. In this article, we list some of these resources, and we also relate some of the adventures we had as our book moved from concept to reality.
Efficient wavelength rerouting in WDM single-fiber and multi-fiber networks with and without wavelength conversion
Authors: G. Mohan, C. Siva Ram Murphy
Venue: Journal of High Speed Networks (2000)

In this paper, we consider wavelength rerouting in circuit switched wavelength-routing Wavelength-Division Multiplexed (WDM) networks. We address the rerouting issue and propose rerouting algorithms for single-fiber and multi-fiber networks with and without wavelength conversion. The wavelength continuity constraint imposed by WDM networks leads to poor blocking performance. The blocking performance can be improved by wavelength rerouting and by providing wavelength conversion capability at the routing nodes. Wavelength rerouting rearranges certain existing lightpaths to accommodate a new connection request. The wavelength continuity constraint is relaxed at the routing nodes having wavelength conversion capability. Since the number of technologically feasible wavelength channels per fiber is very few (up to 16), multi-fiber networks have become an attractive alternative which can support increased traffic with improved performance [3]. Recently, in [1], a rerouting scheme called Parallel Move-To-Vacant-Wavelength Retuning (MTV-WR) with many attractive features such as shorter disruption period and simple switching control, and a rerouting algorithm, for this scheme, to minimize the weighted number of rerouted lightpaths have been proposed. The algorithm runs in polynomial time, but is not time optimal. We present here a time optimal rerouting algorithm to minimize the weighted number of rerouted lightpaths. We also present a rerouting strategy with the same computational complexity for the networks with sparse wavelength conversion. We discuss, how the parallel MTV-WR scheme can be extended to the networks with sparse wavelength conversion for rerouting sub-lightpaths. We also discuss how this scheme can be modified for multi-fiber networks, wherein a lightpath can be moved to a vacant wavelength on any vacant fiber in the bundle of fibers, while maintaining the route. We extend the rerouting algorithm for the single-fiber networks to the multi-fiber networks with the above modified rerouting scheme. The performance of the proposed algorithms are evaluated through extensive simulation. The results show that the proposed algorithms improve the blocking performance significantly.