ppxscal/embedding_network huggingface dataset:
Taming the underlying challenges of reliable multihop routing in sensor networks
Authors: Alec Woo, Terence Tong, David Culler
Venue: Proceedings of the 1st international conference on Embedded networked sensor systems (2003)

The dynamic and lossy nature of wireless communication poses major challenges to reliable, self-organizing multihop networks. These non-ideal characteristics are more problematic with the primitive, low-power radio transceivers found in sensor networks, and raise new issues that routing protocols must address. Link connectivity statistics should be captured dynamically through an efficient yet adaptive link estimator and routing decisions should exploit such connectivity statistics to achieve reliability. Link status and routing information must be maintained in a neighborhood table with constant space regardless of cell density. We study and evaluate link estimator, neighborhood table management, and reliable routing protocol techniques. We focus on a many-to-one, periodic data collection workload. We narrow the design space through evaluations on large-scale, high-level simulations to 50-node, in-depth empirical experiments. The most effective solution uses a simple time averaged EWMA estimator, frequency based table management, and cost-based routing.
Improved Wigner-Ville distribution performance by signal decomposition and modified group delay
Authors: S. V. Narasimhan, Malini B. Nayak
Venue: Signal Processing (2003)

A new approach has been proposed for improving the performance of the Wigner-Ville distribution. This approach is based on signal decomposition and modified magnitude group delay function. Signal decomposition achieved by perfect reconstruction filter bank reduces significantly the existence of crossterms. The Gibbs ripple effect is due to truncation of the Wigner-Ville distribution kernel. The modified magnitude group delay function overcomes this effect without applying any window. Compared to those of Pseudo Wigner-Ville distribution and its versions, the proposed method has significantly improved performance in both time and frequency resolution as there is no time and frequency smoothing. Further, this method obeys better the desirable properties of time-frequency representation and has a better noise immunity.
Crossing the divide
Authors: Jonathan Grudin
Venue: ACM Transactions on Computer-Human Interaction (TOCHI) (2004)

This essay summarizes the editor's views of publication in the field of human-computer interaction. Digital technologies have begun changing the way journal articles and conference papers are produced, reviewed, published, accessed, and used. This period of profound change presents challenges and opportunities for both new and existing channels of scientific and technical communication.
Concept mapping and appropriate instructional strategies in promoting programming skills of holistic learners
Authors: Maria Jakovljevic
Venue: Proceedings of the 2003 annual research conference of the South African institute of computer scientists and information technologists on Enablement through technology (2003)

The current methods for teaching programming skills fail to concentrate on the effective tools and strategies conducive to the creation of in-depth understanding of programming concepts and procedures. Mind tools such as concept mapping are not appropriately investigated in the present programming classrooms. Thus the needs of learners, particularly the holistic learners, are neglected.The aim of this paper is to explore concept mapping and instructional strategies applicable in promoting programming skills of holistic learners. The nature of this research required a qualitative research approach where individual interviewing was used to gather data. Ten students at the institution for higher education were identified as holistic learners with a pre-screening device.The findings of this study reveal the necessity for concept mapping and a peer-based collaborative environment in order to enhance a meaningful programming atmosphere. Holistic learners commented that concept mapping enhanced their learning, as it stimulated simultaneous, deductive or intuitive, concrete, and subjective processes relevant to their style of learning. Concept mapping enabled learners to focus on fine details, experiencing a structured step-by-step approach, representing their knowledge structures graphically and visualising programming concepts and procedures as a network of interrelated ideas. Findings indicated a need for concept mapping to be used in conjunction with practical and cognitive apprenticeship. This will enlarge and strengthen the insight into the programming process and set a climate for enhancing programming skills of holistic learners.
An Exploratory Study of Alignment Issues of IT Acceptance with Professionals in a Project Setting
Authors: Vernon Bachor, Mike Chiasson
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 8 - Volume 8 (2004)

The information technology (IT) literature has demonstrated a link with business performance and effectiveness when IT and business objectives are aligned. However, project settings and joint-venture projects in particular, challenge the way alignment has been conceptualized, exposing other sources of alignment. Projects require a quick diffusion of IT to many different stakeholders with different individual and group interests representing many professions with different professional affiliations. Coordinating the diverse groups of individual expertise that often have short stays and weak allegiance to the project is quite difficult. These factors lead to many types of incentive problems in learning and using new IT necessary for project success. This potentially leads to individuals rejecting or bypassing the use of mandated information technology when the individual's personal, group or professional interests do not coincide with project objectives. As a result, a joint venture project setting challenges the underlying assumptions of Diffusion of Innovation Theory and Technology Acceptance Model, thus providing an important contribution for theoretical development in the IT diffusion literature. Therefore, an important research question for IT diffusion, arising from project situations, is: How are individual professional and project incentives aligned in order to diffuse the necessary IT to achieve coordination and project success? The results of this exploratory study conclude that alignment issues affecting an individual's IT acceptance on joint venture projects originates from many unexplored sources. These five alignment issues include objectives, work output, work value, technology expectations, and peers and are required by the individual, their originating company, the project, and the owner company. Each of thesealignment issues reveals different aspects of a complex negotiated order to IT diffusion.
On the Modeling of Passive Motion of the Human Knee Joint by Means of Equivalent Planar and Spatial Parallel Mechanisms
Authors: Vincenzo Parenti-Castelli, Alberto Leardini, Raffaele Di Gregorio, John J. O'Connor
Venue: Autonomous Robots (2004)

Recent literature in biomechanics has demonstrated that motion of the human knee joint in virtually unloaded conditions is guided in a single and complex path by the passive structures of the joint alone. It has been deduced that the joint behaves as a single degree of freedom mechanism. Early models, dated on beginning of this century, showed this in the sagittal plane only. The three dimensional motion has been recently modelled by means of equivalent parallel mechanisms, based also on experimental observations on knee specimens of two separate frictionless contacts and three isometric ligament fibres.The model of the joint is a key tool for a deeper understanding of the knee motion and the design of reliable and efficient prostheses. It also provides useful information for the planning of surgical intervention on the basic structures of the knee.The progress of this modelling is reported in this paper. A medical and biomechanical rationale for these studies is provided, together with a number of relevant publications. The pioneering planar four-bar linkage has been initially advanced to a single degree of freedom equivalent spatial mechanism characterised by plane-to-sphere contacts. The closure equations for this mechanism have been progressively simplified. Extensions to more complex articular surfaces have been also performed. The results reported for all these models demonstrate that the original model assumptions were valid and that refinements in articular surface descriptions are justified to a certain extent.
Detection of Changes in the Properties of Time-Varying Random Processes
Authors: E. A. Grebenyuk
Venue: Automation and Remote Control (2003)

An approach to analyzing and predicting systems described by time-varying series is developed on the basis of identification of intervals in which time-varying processes do not change their parameters and construction of models for cointegration relations in these intervals and for tracking the changes both in the processes themselves and in the long-range cointegration relations formed by them. CUSUM-type detection algorithms are constructed for detecting the changes in time-varying processes and identifying stationary intervals. If the process parameters are known exactly, these algorithms are optimal by the quickest detection criterion. For the case studied in the paper, the process parameters are not known after the changes in properties, only certain assumptions concerning the type of parameter changes can be made. Therefore, property changes are detected with the help of modified CUSUM-algorithms, which are not optimal, but guarantee a reasonable detection quality.
On the number of hexagonal polyominoes
Authors: Markus Vöge, Anthony J. Guttmann
Venue: Theoretical Computer Science (2003)

A combination of the refined finite lattice method and transfer matrices allows a radical increase in the computer enumeration of polyominoes on the hexagonal lattice (equivalently, site clusters on the triangular lattice), pn with n hexagons. We obtain pn for n ≤ 35. We prove that pn=τn+o(n), obtain the bounds 4.8049 ≤ τ ≤ 5.9047, and estimate that τ=5.1831478(17). Finally, we provide compelling numerical evidence that the generating function Σ pnzn ≈ A(z)log(1-τz), for z → (1/τ)- with A(z) holomorphic in a cut plane, estimate A(1/τ) and predict the sub-leading asymptotic behaviour, identifying a non-analytic correction-to-scaling term with exponent Δ=3/2. On the basis of universality and previous numerical work we argue that the mean-square radius of gyration 〈Rg2〉n of polyominoes of size n grows as n2v, with v = 0.64115(5).
A Model for Multi-Stage Production Planning with Load Dependent Lead Times
Authors: David L. Woodruff, Stefan Voβ
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 3 - Volume 3 (2004)

As organizations move from creating plans for individual production lines to entire supply chains it is increasingly important to recognize that decisions concerning utilization ofproduction resources impact the lead times that will be experienced. In this paper we give some insights into why this is the case by looking at the queuing that results in delays. We have then used these insights to suggest an optimization model that takes into account load dependent lead times and routing alternatives.
Some thoughts on computers and greatness in teaching
Authors: Thomas A. Dwyer
Venue: ACM SIGCUE Outlook (1975)

This paper argues that computers are the first form of educational technology that can be honestly described as "revolutionary". It also argues that this is because the real forte of computers is to support person-to-person educational influence, not replace it. This suggests that it is timely to reexamine the goal of "great teaching" in a system dedicated to mass education, but for very different reasons from those implied by early work in computer-assisted instruction. The consequences of such a viewpoint for both teacher education and in-school practice are discussed.
Modeling and Verifying a Lego Car Using Hybrid I/O Automata
Authors: Ansgar Fehnker, Frits Vaandrager, Miaomiao Zhang
Venue: Proceedings of the Third International Conference on Quality Software (2003)

We illustrate the application of the hybrid I/O automataframework of Lynch, Segala & Vaandrager by using it tomodel and analyze the behavior of a simple Lego car withcaterpillar treads. We derive constraints on the values ofthe parameters that occur in our hybrid model that guaranteethat the car will always move forward along a blacktape, and will never get off the tape or move backward. Inorder to simplify the correctness proof, we introduce a transitionsystems that abstracts from the hybrid automaton in arather drastic manner, but still preserves validity of the correctnessproperties in which we are interested. Even thoughour original model does not involve any disturbances, thegeneral parametric analysis of the system allows us to extendour results in a trivial manner to a hybrid model inwhich several disturbances are allowed (mistakes in measurementsof lengths, drift and jitter of the hardware clock,velocity, and distance between the two caterpillar treads).
An accurate model of squirrel cage induction machines under stator faults
Authors: V. Devanneaux, B. Dagues, J. Faucher, G. Barakat
Venue: Mathematics and Computers in Simulation (2003)

A substantial portion of squirrel cage induction motor faults are stator related. An accurate transient model of squirrel cage induction machines under stator faults is presented here. A coupled magnetic circuits approach is used and very few restrictive assumptions are made. All parameters are calculated from the actual geometry and winding layout of the machines rather than from transformed or equivalent variables. The detailed depiction of the procedure needed to implement such an accurate model with simulation results is the subject of this paper.
2D Z-string: a new spatial knowledge representation for image databases
Authors: Anthony J. T. Lee, Han-Pang Chiu
Venue: Pattern Recognition Letters (2003)

The knowledge structure called the 2D C+-string, proposed by Huang et al., to represent symbolic pictures allows a natural way to construct iconic indexes for images. According to the cutting mechanism of the 2D C+-string, an object may be partitioned into several subparts The number of partitioned subparts is bounded to O(n2), where n is the number of objects in the image. Hence, the string length is also bounded to O(n2). In this paper, we propose a new spatial knowledge representation called the 2D Z-string. Since there are no cuttings between objects in the 2D Z-string, the integrity of objects is preserved and the string length is bounded to O(n). Finally, some experiments are conducted to compare the performance of both approaches.
Multiple query optimization support for data analysis applications
Authors: Henrique C. M. Andrade
Venue:  (2003)

The efficient storage, management, and manipulation of large datasets is important in many fields of science, engineering and business. Simulations and experimental measurements are the main sources of data in these fields and the amount of data available for analyzing is increasing at a very high pace due both to the increased capability to collect and store data, as well as to the capability for processing it. We broadly define these applications as data analysis applications. Their main characteristic is that they usually access a subset of all the data available&mdash;the hot spots&mdash;which are the data points of highest interest in generating data products. In many cases, data analysis is employed in a collaborative environment, where multiple clients access the same datasets and perform similar processing on the data. For instance, in medical training, a large group of students may want to simultaneously explore a similar set of digitized microscopy slides, or visualize the same high resolution Magnetic Resonance Imaging (MRI) results. In this case, the data server needs to process multiple queries simultaneously to minimize latency to the clients. Previously investigated multi-query optimization (MQO) techniques do not account for user-defined processing of data and user-defined aggregation methods which are typical of data analysis queries. Therefore, the problem we investigate in this dissertation is multiple query optimization for data analysis applications. It can be broadly defined as a set of techniques aimed at minimizing the total cost of processing a series of queries by creating an optimized access plan for the entire set of queries and for reusing previously computed aggregates. The main goal of our work is to provide a generic optimization framework that can be used as a common platform to deploy data analysis applications that are able to efficiently handle multiple simultaneous queries and can leverage previously computed results to partially or fully compute new queries. In this work, we show significant improvements in data management issues. These include the integration of an active semantic cache approach coupled with a data transformation model for reusing data and computation, a functional decomposition frame work for exposing reuse sites, query scheduling policies, and cache replacement policies. Finally, we show how all these techniques can be adequately implemented over new computation and execution model paradigms such as clusters of PCs and highly distributed, heterogeneous data grid environments.
Are European IS journals under-rated? an answer based on citation analysis
Authors: Pairin Katerattanakul, Bernard Han
Venue: European Journal of Information Systems (2003)

A concern that the quality of European IS journals has been under-rated by existing studies was recently addressed in the IS community. In this study, an objective method based on a Citation Analysis was employed to re-examine the quality of four established European IS journals as compared to 11 other well-recognized IS journals. Extensive citation data were collected to derive eight indices as the measures of journal quality. Our research results indicate that the quality of the four leading European IS journals is quite comparable to that of other well-known IS journals reported in prior studies.
Finding All Maximal Cliques in Dynamic Graphs
Authors: Volker Stix
Venue: Computational Optimization and Applications (2004)

Clustering applications dealing with perception based or biased data lead to models with non-disjunct clusters. There, objects to be clustered are allowed to belong to several clusters at the same time which results in a fuzzy clustering. It can be shown that this is equivalent to searching all maximal cliques in dynamic graphs like Gt &equals; (V,Et), where Et &minus; 1 &sub; Et, t &equals; 1,&hellip;,T; E0 &equals; &phis;. In this article algorithms are provided to track all maximal cliques in a fully dynamic graph.
Establishing Pairwise Keys for Secure Communication in Ad Hoc Networks: A Probabilistic Approach
Authors: Sencun Zhu, Shouhuai Xu, Sanjeev Setia, Sushil Jajodia
Venue: Proceedings of the 11th IEEE International Conference on Network Protocols (2003)

A prerequisite for secure communication between two nodes in an ad hoc network is that the nodes share a key to bootstrap their trust relationship. In this paper, we present a scalable and distributed protocol that enables two nodes to establish a pairwise shared key on the fly, without requiring the use of any on-line key distribution center. The design of our protocol is based on a novel combination of two techniques ¿ probabilistic key sharing and threshold secret sharing. Our protocol is scalable since every node only needs to possess a small number of keys, independent of the network size, and it is computationally efficient because it only relies on symmetric key cryptography based operations. We show that a pairwise key established between two nodes using our protocol is secure against a collusion attack by up to a certain number of compromised nodes. We also show through a set of simulations that our protocol can be parameterized to meet the desired levels of performance, security and storage for the application under consideration.
Elucidative Programming in open integrated development environments for Java
Authors: Thomas Vestdam
Venue: Proceedings of the 2nd international conference on Principles and practice of programming in Java (2003)

In this paper we present an integration of tool support for internal documentation in the modern IDE Together J. The specific kind of internal documentation stems from the Elucidative Programming tradition where documentation and source code are separate entities tied together using hyperlinks. The tool supports the programmer in creating and managing internal documentation of Java source code. The hypertext-based documentation is presented in the IDE where a range of navigational features helps the programmer with finding relevant documentation for a given part of the source code. It is concluded that integration of such a tool is indeed possible as well as easy to do in an open IDE like TogetherJ. We expect that we can obtain similar results using other open IDEs.
Roles of computing in P5BL: Problem-, project-, product-, process-, and people-based learning
Authors: Renate Fruchter
Venue: Artificial Intelligence for Engineering Design, Analysis and Manufacturing (1998)

This position paper proposes the P5BL initiative and vision, that is, Problem-, Project-, Product-, Process-, People-Based Learning. A definition is proposed for the P5BL teaching and learning approach. The discussion identifies key pedagogical issues and innovative roles of computing for each of the five critical Ps in a multisite, cross-disciplinary, project-centered, and team-oriented Architecture/Engineering/Construction environment.
Automation of a Robotic Arm by Analysing the CAN Protocol
Authors: Heriberto I. Hernández Martínez, Carlos A. Chamú Morales, Oswaldo Arias Martínez
Venue: Proceedings of the 14th International Conference on Electronics, Communications and Computers (2004)

The CAN bus has had great acceptance in severalareas such as industrial automation processes. Differentsolutions and profiles for standardising the communicationbetween devices and systems have beenwell accepted. This paper presents a general introductionbased on different areas in which the CAN protocolhas been applied. In addition, a definition of theprotocol's architecture and a description of the toolsand devices of the system are presented. Finally, adevelopment of methodology in the application to theautomation and the results obtained in this work areshown.Thus, based on earlier experiences in the developmentof applications using the CAN protocol, principallywith academic purposes, the authors present astudy of the analysis of the CAN protocol applied to areal application like the robotic arm automation.The importance of this work increases due to thelimited knowledge of the protocol implemented and thedifficulty that the analysis carried out has into this realapplication.
A special identity between three 2F1(a,b;c;4) hypergeometric series
Authors: G. Vanden Berghe, H. De Meyer
Venue: Journal of Computational and Applied Mathematics (2003)

As a by-product of the calculation of eigenvalues of a particular SO(3) invariant operator in the enveloping algebra of SO(5), a three terms relation between three hypergeometric series emerges.