ppxscal/embedding_network huggingface dataset:
Openness in shared hypermedia workspaces: the case for collaborative open hypermedia systems
Authors: Jörg M. Haake, Uffe K. Wiil, Peter J. Nürnberg
Venue: ACM SIGWEB Newsletter (1999)

Group work requires much flexibility regarding both the organization of shared workspaces and the organization of collaborative work. Shared hypermedia workspaces can provide this flexibility. However, this requires the provision of openness with respect to both the hypermedia workspace and the collaboration support offered in such a collaborative open hypermedia system. In this paper we address the issue of how to identify key requirements of open collaborative hypermedia systems. We start with a scenario in order to come up with a preliminary set of requirements. We then apply a regular schema to generate a more comprehensive set of requirements for open collaborative hypermedia systems.
Near-optimal hardness results and approximation algorithms for edge-disjoint paths and related problems
Authors: Venkatesan Guruswami, Sanjeev Khanna, Rajmohan Rajaraman, Bruce Shepherd, Mihalis Yannakakis
Venue: Journal of Computer and System Sciences (2003)

We study the approximability of edge-disjoint paths and related problems. In the edge-disjoint paths (EDP) problem, we are given a network G with source-sink pairs (si, ti), 1 ≤i≤k, and the goal is to find a largest subset of source-sink pairs that can be simultaneously connected in an edge-disjoint manner. We show that in directed networks, for any ε>0, EDP is NP-hard to approximate within m1/2-ε. We also design simple approximation algorithms that achieve essentially matching approximation guarantees for some generalizations of EDP. Another related class of routing problems that we study concerns EDP with the additional constraint that the routing paths be of bounded length. We show that, for any ε > 0, bounded length EDP is hard to approximate within m1/2-ε even in undirected networks, and give an O(√m)-approximation algorithm for it. For directed networks, we show that even the single source-sink pair case (i.e. find the maximum number of paths of bounded length between a given source-sink pair) is hard to approximate within m1/2-ε, for any ε > 0.
Adaptive Wavelet Schemes for Nonlinear Variational Problems
Authors: Albert Cohen, Wolfgang Dahmen
Venue: SIAM Journal on Numerical Analysis (2003)

We develop and analyze wavelet based adaptive schemes for nonlinear variational problems. We derive estimates for convergence rates and corresponding work counts that turn out to be asymptotically optimal. Our approach is based on a new paradigm that has been put forward recently for a class of linear problems. The original problem is transformed first into an equivalent one which is well posed in the Euclidean metric $\ell_2$. Then conceptually one seeks iteration schemes for the infinite dimensional problem that exhibits at least a fixed error reduction per step. This iteration is then realized approximately through an adaptive application of the involved operators with suitable dynamically updated accuracy tolerances. The main conceptual ingredients center around nonlinear tree approximation and the sparse evaluation of nonlinear mappings of wavelet expansions. We prove asymptotically optimal complexity for adaptive realizations of first order iterations and of Newton's method.
JAM: A Jammed-Area Mapping Service for Sensor Networks
Authors: Anthony D. Wood, John A. Stankovic, Sang H. Son
Venue: Proceedings of the 24th IEEE International Real-Time Systems Symposium (2003)

Preventing denial-of-service attacks in wireless sensor networks is difficult primarily because of the limited resources available to network nodes and the easewith which attacks are perpetrated. Rather than jeopardize design requirements which call for simple, inexpensive, mass-producible devices, we propose a coping strategy that detects and maps jammed regions. We describea mapping protocol for nodes that surround a jammerwhich allows network applications to reason about the region as an entity, rather than as a collection of brokenlinks and congested nodes. This solution is enabled bya set of design principles: loose group semantics, eagereavesdropping, supremacy of local information, robustness to packet loss and failure, and early use of results.Performance results show that regions can be mapped in1 - 5 seconds, fast enough for real-time response. Witha moderately connected network, the protocol is robust tofailure rates as high as 25 percent.
MJoin: a metadata-aware stream join operator
Authors: Luping Ding, Elke A. Rundensteiner, George T. Heineman
Venue: Proceedings of the 2nd international workshop on Distributed event-based systems (2003)

Join algorithms must be re-designed when processing stream data instead of persistently stored data. Data streams are potentially infinite and the query result is expected to be generated incrementally instead of once only. Data arrival patterns are often unpredictable and the statistics of the data and other relevant metadata often are only known at runtime. In some cases they are supplied interleaved with the actual data in the form of stream markers. Recently, stream join algorithms, like Symmetric Hash Join and XJoin, have been designed to perform in a pipelined fashion to cope with the latent delivery of data. However, none of them to date takes metadata, especially runtime metadata, into consideration. Hence, the join execution logic defined statically before runtime may not be well suited to deal with varying types of dynamic runtime scenarios. Also the potentially unbounded state needs to be maintained by the join operator to guarantee the precision of the result. In this paper, we propose a metadata-aware stream join operator called MJoin which is able to exploit metadata to (1) detect and purge useless materialized data to save computation resources and (2) optimize the execution logic to target diferent optimization goals. We have implemented the MJoin operator. The experimental results validate our metadata-driven join optimization strategies.
A high-speed energy-efficient 64-bit reconfigurable binary adder
Authors: Stefania Perri, Pasquale Corsonello, Giuseppe Cocorullo
Venue: IEEE Transactions on Very Large Scale Integration (VLSI) Systems (2003)

Datapaths for media signal processing are typically built using programmable computational elements such as adders and multipliers, which can be run-time reconfigured to operate on simple integers with 8, 16, or 32 bits of precision. In this brief, a new high-speed energy-efficient reconfigurable adder for media signal processing is presented. The proposed circuit is based on carry-propagation schemes and can be partitioned to perform one 64-, two 32-, four 16-, and eight 8-bit additions. When the Austria Mikro System (AMS) 0.35 µm 2-poly 3-metal 3.3 V CMOS (CSD) process is used to produce layout, a worst propagation delay of about 4.9 ns and an average energy dissipation of about 181 µW/MHz are obtained.
Development of Evidence-Based Medicine Resources: Bridging Clinical Research to Medical Practice
Authors: Paul Fontelo, Michael Ackerman, George Kim
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 6 - Volume 6 (2004)

We are developing resources for continuous and ubiquitous access to National Library of Medicine (NLM) information sources (MEDLINE, PubMed, and Clinical Trials) for the mobile physician and healthcare provider to support the practice of evidence-based medicine. We established wireless networks (802.11b, Infrared, Bluetooth) and created applications to search these databases. We also developed a content server with the main purpose of providing content to PDAs and handheld devices. We present our yearlong experience and evaluation of handheld devices, wireless access capabilities and analysis of log access data from servers. Interaction with users and online feedback will be discussed.
Synthesis of Low Power High Performance Dual-VT PTL Circuits
Authors: Debasis Samanta, Ajit Pal
Venue: Proceedings of the 17th International Conference on VLSI Design (2004)

Although major portion of power dissipation in presentgeneration CMOS circuits (250nm - 180nm) is due tocharging and discharging of various node capacitors, knownas switching power, the leakage power is becoming moreand more predominant in ultra-deep submicron (UDSM)technologies. In pass-transistor logic (PTL) circuits, theoutput of each PTL cell is provided with a buffer to reducedelay and restore voltage level. These buffers, in turn, arethe primary source of leakage power in PTL circuits. In thispaper we have proposed, for the first time, the use oftransistors of two threshold voltages (dual-VT) to minimizeleakage power. We have extended our existing algorithm forlogic synthesis of dual-VT PTL circuits. The extendedalgorithm has been tested for a large number of ISCASbenchmark circuits. Experimental results show that the useof dual-VT leads to a reduction in leakage power of about45% in active mode and 76% in standby mode compared totheir single-VT realization. Moreover, total powerdissipation reduces by 18% with respect to single-VTrealizations.
Rational approximation schemes for rotation-minimizing frames on Pythagorean-hodograph curves
Authors: Rida T. Farouki, Chang Yong Han
Venue: Computer Aided Geometric Design (2003)

An adapted frame (t, u, v) on a space curve r(ξ) is a right-handed set of three orthonormal vectors, where t is the unit tangent and u, v span the curve normal plane. For such frames to have a rational dependence on the curve parameter, r(ξ) must be a Pythagorean-hodograph (PH) curve, since only PH curves have rational unit tangent vectors. Among all possible adapted frames, the rotation-minimizing frame (RMF) is the most attractive for applications such as animation, swept surface constructions, and motion planning. The PH curves admit exact RMF descriptions, but they involve transcendental (logarithmic) functions. Since rational forms are generally preferred, the problem of rational approximation of RMFs for PH curves is considered herein. This is accomplished by employing the Euler-Rodrigues frame (ERF) as a reference (the ERF is rational and, unlike the Frenet frame, does not suffer indeterminacies at inflections). The function that describes the angular deviation between the RMF and ERF is derived in closed form, and is approximated by Padé (rational Hermite) interpolation. In typical cases, these interpolants furnish compact approximations of excellent accuracy, amenable to use in a variety of applications.
How Effective is Stemming and Decompounding for German Text Retrieval?
Authors: Martin Braschler, Bärbel Ripplinger
Venue: Information Retrieval (2004)

Information retrieval systems operating on free text face difficulties when word forms used in the query and documents do not match. The usual solution is the use of a &ldquo;stemming component&rdquo; that reduces related word forms to a common stem. Extensive studies of such components exist for English, but considerably less is known for other languages. Previously, it has been claimed that stemming is essential for highly declensional languages. We report on our experiments on stemming for German, where an additional issue is the handling of compounds, which are formed by concatenating several words. The major contribution of our work that goes beyond its focus on German lies in the investigation of a complete spectrum of approaches, ranging from language-independent to elaborate linguistic methods. The main findings are that stemming is beneficial even when using a simple approach, and that carefully designed decompounding, the splitting of compound words, remarkably boosts performance. All findings are based on a thorough analysis using a large reliable test collection.
A Novel Bag Generator for Image Database Retrieval With Multi-Instance Learning Techniques
Authors: Zhi-Hua Zhou, Min-Ling Zhang, Ke-Jia Chen
Venue: Proceedings of the 15th IEEE International Conference on Tools with Artificial Intelligence (2003)

In multi-instance learning, the training examples are bags composed of instances without labels and the task is to predict the labels of unseen bags through analyzing the training bags with known labels. In content-based image retrieval (CBIR), the query is ambiguous because it is hard to ask the user precisely specify what he or she wants. Such kind of ambiguity can be gracefully dealt with by multi-instance learning techniques, and previous research shows that bag generators can significantly in.uence the performance of a CBIR system. In this paper, a novel bag generator named ImaBag is presented, where the pixels of each image are first clustered based on their color and spatial features and then the clustered blocks are merged and converted into a specific number of instances. Experiments show that ImaBag achieves comparable results to some existing bag generators but is more efficient in retrieving images from databases.
Facilitating Knowledge Creation by Knowledge Assets
Authors: Shih-Wei Chou, Mong-Young He
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 8 - Volume 8 (2004)

A comprehensive and feasible model that delineates the interrelationships between knowledge assets and knowledge creation processes is absent. This study aims to fill this void. Unlike previous research, this study investigates the interrelations among four categories of knowledge assets and four knowledge creation processes -- socialization, externalization, combination, and internalization (SECI). In our framework, we argued that different types of knowledge assets may have differing influences on knowledge creation. In order to test the feasibility of this framework, we conducted an empirical research. This study employed a survey instrument to collect data from a wide variety of organizations in manufacturing, trade, transportation and service industries, computer industries, finance, and academic institution. A total of 204 usable responses were analyzed. We identified four inter-relationships from this study. (1) Compared to other knowledge assets, conceptual knowledge assets have a greater effect on externalization of knowledge creation process; (2) Compared to other knowledge assets, routine knowledge assets have a greater effect on socialization of knowledge creation process; (3) Compared to other knowledge assets, experiential knowledge assets do not have a greater effect on internalization of knowledgecreation process; and (4) Compared to other knowledge assets, systemic knowledge assets do not have a greater effect on combination of knowledge creation process. The implications of the study are discussed, and further research directions are proposed.
Architectures and algorithms for control and diagnostics of coupled-bunch instabilities in circular accelerators
Authors: John D. Fox
Venue:  (2003)

Modern light sources and circular colliders employ large numbers of high-intensity particle bunches in order to achieve high luminosity. The electromagnetic coupling of bunches via resonant structures causes coherent instabilities at high beam currents. Achieving high luminosity requires the control of such unstable motion. Feedback control is challenging due to wideband nature of the problem with up to 250 MHz bandwidths required. This thesis presents digital signal processing architectures and diagnostic techniques for control of longitudinal and transverse coupled-bunch instabilities. Diagnostic capabilities integrated into the feedback system allow one to perform fast transient measurements of unstable dynamics by perturbing the beam from the controlled state via feedback and recording the time-domain response. Such measurements enable one to thoroughly characterize plant (beam) dynamics as well as performance of the feedback system. Beam dynamics can change significantly over the operating range of accelerator currents and energies. Here we present several methods for design of robust stabilizing feedback controllers. Experimental results from several accelerators are presented. A new baseband architecture for transverse feedback is described that compactly implements the digital processing functions using field-programmable gate array devices. The architecture is designed to be software configurable so that the same hardware can be used for instability control in different accelerators.
An expert system for pneumatic design
Authors: Heung-Yeoul Shin, Jae-Won Lee
Venue: Artificial Intelligence for Engineering Design, Analysis and Manufacturing (1998)

One of the biggest problems in pneumatic system design is over design. Thus, the results are excessive in costs of the initial investment and it requires too much energy. This article describes the development of expert system based pneumatic design system, PNEUDES (PNEUmatic Design Expert System), prototype that enables the user the optimal design of pneumatic system. Once the design requirements such as cylinder type and work load, etc. are input to the system, optimal cylinder specifications with standardized order-based size, valves types, and necessary accessories are all determined. Also the configuration information such as the connectivity among components and cylinder image data are supplied to the user. It can also help the novice of pneumatic design. The rule-based reasoning approach is used as a reasoning strategy with Intelligent Rule Element shell.
Selecting the best valid scopes for wireless dissemination of location-dependent data
Authors: Baihua Zheng, Wang-Chien Lee, Dik Lun Lee
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

Mobility of user poses new challenges to research on spatial data access. Spatial data cached in the mobile client may become invalid because of the movement of the client. To increase the reusability of the cached data, we can identify the valid scope of the spatial data (i.e., the spatial area within which the data is known to be valid) and save the valid scope as well as the data in the cache. In this paper, we study issues on the dissemination of spatial data and valid scopes in a wireless environment. We investigate methods for representing valid scopes and their impacts on system performance. A generic representation method, called the invalidation-efficiency-based (IEB) method, is proposed. Simulation experiments are conducted to compare the performance of IEB with other representation methods. Result shows that IEB is superior to the other methods because it tries to balance the precision and overhead of valid scopes.
Kinetic solution of the Boltzmann-Peierls equation
Authors: Matthias Kunik, Shamsul Qamar, Gerald Warnecke
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

This paper is concerned with the solutions of initial value problems of the Boltzmann-Peierls equation (BPE). This integro-differential equation describes the evolution of heat in crystalline solids at very low temperatures. The BPE describes the evolution of the phase density of a phonon gas. The corresponding entropy density is given by the entropy density of a Bose-gas. We derive a reduced three-dimensional kinetic equation which has a much simpler structure than the original BPE. Using special coordinates in the one-dimensional case, we can perform a further reduction of the kinetic equation. Making a one-dimensionality assumption on the initial phase density one can show that this property is preserved for all later times. We derive kinetic schemes for the kinetic equation as well as for the derived moment systems. Several numerical test cases are shown in order to validate the theory.
A Comparative Evaluation of Length Estimators of Digital Curves
Authors: David Coeurjolly, Reinhard Klette
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2004)

Abstract--This paper compares previously published length estimators in image analysis having digitized curves as input. The evaluation uses multigrid convergence (theoretical results and measured speed of convergence) and further measures as criteria. This paper also suggests a new gradient-based method for length estimation, and combines a previously proposed length estimator for straight segments with a polygonalization method.
Characterizing Overlay Multicast Networks
Authors: Sonia Fahmy, Minseok Kwon
Venue: Proceedings of the 11th IEEE International Conference on Network Protocols (2003)

Overlay networks among cooperating hosts have recently emerged as a viable solution to several challenging problems, including multicasting, routing, content distribution, and peer-to-peer services. Application-level overlays, however, incur a performance penalty over router-level solutions. This paper characterizes this performance penalty for overlay multicast trees via experimental data, simulations, and theoretical models. Experimental data and simulations illustrate that (i) the average delay and the number of hops between parent and child hosts in overlay trees generally decrease, and (ii) the degree of hosts generally decreases, as the level of the host in the overlay tree increases. Overlay multicast routing strategies, together with power-law and small-world Internet topology characteristics, are causes of the observed phenomena.We compare three overlay multicast protocols with respect to latency, bandwidth, router degrees, and host degrees. We also quantify the overlaytree cost. Results reveal that \frac{{L(n)}}{{U(n)}}\alpha n^{0.9} for small n, where L(n) is the total number of hops in all overlay links, U(n) is the average number of hops on the source to receiver unicast paths, and n is the number of members in the overlay multicast session.
Rapid Verification of Embedded Systems Using Patterns
Authors: W. T. Tsai, L. Yu, F. Zhu, R. Paul
Venue: Proceedings of the 27th Annual International Conference on Computer Software and Applications (2003)

Verification pattern (VP) is a new technique to testembedded systems rapidly, and it has been used to testindustrial safety-critical embedded systems successfully.The key concept of this approach is to classify systemscenarios into patterns, and use the same code templateto test all the scenarios of the same pattern. In this way,testing effort can be greatly reduced. This paper extendsVPs so that they can fully interoperate with a formalizedscenario model ACDATE. In this way, various static anddynamic analyses can be performed on system scenariosas well as on system patterns. Furthermore, this paperprovides a mapping from system scenarios into temporallogic expressions. In this way, a practitioner can specifysystem constraints in scenarios, and follow the mappingto obtain the temporal logic expressions easily to performformal model checking. This paper also provides an OOframework to support automated test script developmentfrom VPs. In this way, VPs can be used in an integratedprocess where both semi-formal analyses and formaltechniques can be used together to develop mission-criticalembedded applications.