ppxscal/embedding_network huggingface dataset:
Coverage issues in wireless sensor networks
Authors: Sesh Commuri
Venue:  (2006)

A fundamental issue in the deployment of a large scale Wireless Sensor Network (WSN) is the ability of the network to cover the region of interest. While it is important to know if the region is covered by the deployed sensor nodes, it is of even greater importance to determine the minimum number of these deployed sensors that will still guarantee coverage of the region. This issue takes on added importance as the sensor nodes have limited battery power. Redundant sensors affect the communications between nodes and cause increased energy expenditure due to packet collisions. While scheduling the activity of the nodes and designing efficient communication protocols help alleviate this problem, the key to energy efficiency and longevity of the wireless sensor network is the design of efficient techniques to determine the minimum set of sensor nodes for coverage. Currently available techniques in the literature address the problem of determining coverage by modeling the region of interest as a planar surface. Algorithms are then developed for determining point coverage, area coverage, and barrier coverage. The analysis in this thesis shows that modeling the region as a two dimensional surface is inadequate as most applications in the real world are in a three dimensional space. The extension of existing results to three dimensional regions is not a trivial task and results in inefficient deployments of the sensor networks. Further, the type of coverage desired is specific to the application and the algorithms developed must be able to address the selection of sensor nodes not only for the coverage, but also for covering the border of a region, detecting intrusion, patrolling a given border, or tracking a phenomenon in a given three dimensional space. These are very important issues facing the research community and the solution to these problems is of paramount importance to the future of wireless sensor networks. In this thesis, the coverage problem in a three dimensional space is rigorously analyzed and the minimum number of sensor nodes and their placement for complete coverage is determined. Also, given a random distribution of sensor nodes, the problem of selecting a minimum subset of sensor nodes for complete coverage is addressed. A computationally efficient algorithm is developed and implemented in a distributed fashion. Numerical simulations show that the optimized sensor network has better energy efficiency compared to the standard random deployment of sensor nodes. It is demonstrated that the optimized WSN continues to offer better coverage of the region even when the sensor nodes start to fail over time. (Abstract shortened by UMI.)
Efficient Dynamic Multikeys in Enterprise JavaBeans
Authors: Reinhard Klemm
Venue: Proceedings of the 11th IEEE International Conference on Engineering of Complex Computer Systems (2006)

The J2EE platform allows the rapid development of a large class of complex and robust server-side applications. However, some J2EE constraints pose serious challenges to the development of J2EE applications that interact with legacy systems outside the originally targeted J2EE domain. One such constraint is the static nature of identities of entity Enterprise JavaBeans (EJBs). We present a case study that motivates the introduction of dynamic sets of identities of entity EJBs, which we call dynamic multikeys, and describe five different ways of implementing dynamic multikeys based on static EJB identities. We compare the characteristics of our dynamic multikey solutions and demonstrate through performance tests that one of them is superior from a performance point of view. However, each one of the slower solutions offers distinct advantages that may make it attractive to some developers and for applications where the performance of dynamic multikeys is not a critical factor.
Multi-item dynamic production-distribution planning in process industries with divergent finishing stages
Authors: Nafee Rizk, Alain Martel, Sophie D'Amours
Venue: Computers and Operations Research (2006)

This paper examines a multi-item dynamic production-distribution planning problem between a manufacturing location and a distribution center. Transportation costs between the manufacturing location and the distribution center offer economies of scale and can be represented by general piecewise linear functions. The production system at the manufacturing location is a serial process with a multiple parallel machines bottleneck stage and divergent finishing stages. A predetermined production sequence must be maintained on the bottleneck machines. A tight mixed-integer programming model of the production process is proposed, as well as three different formulations to represent general piecewise linear functions. These formulations are then used to develop three equivalent mathematical programming models of the manufacturer-distributor flow planning problem. Valid inequalities to strengthen these formulations are proposed and the strategy of adding extra 0-1 variables to improve the branching process is examined. Tests are performed to compare the computational efficiency of these models. Finally, it is shown that by adding valid inequalities and extra 0-1 variables, major computational improvements can be achieved.
LIME: A coordination model and middleware supporting mobility of hosts and agents
Authors: Amy L. Murphy, Gian Pietro Picco, Gruia-Catalin Roman
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (2006)

LIME (Linda in a mobile environment) is a model and middleware supporting the development of applications that exhibit the physical mobility of hosts, logical mobility of agents, or both. LIME adopts a coordination perspective inspired by work on the Linda model. The context for computation, represented in Linda by a globally accessible persistent tuple space, is refined in LIME to transient sharing of the identically named tuple spaces carried by individual mobile units. Tuple spaces are also extended with a notion of location and programs are given the ability to react to specified states. The resulting model provides a minimalist set of abstractions that facilitates the rapid and dependable development of mobile applications. In this article we illustrate the model underlying LIME, provide a formal semantic characterization for the operations it makes available to the application developer, present its current design and implementation, and discuss lessons learned in developing applications that involve physical mobility.
Fuzzy data mining for customer loyalty analysis
Authors: Jay B. Simha, S. S. Iyengar
Venue: Proceedings of the 9th International Conference on Information Technology (2006)

One of the major conceptual analyses in analytical CRM is customer loyalty. Current methods use user defined and statistical methods for loyalty analysis. One of the major limitations of these methods is that they assign every customer into exactly one segment, which may be counter intuitive. In this paper a novel approach using fuzzy logic has been discussed. The proposed method uses fuzzy context model to extract the customer membership to a segment of interest. A real life case study shows promising results for the proposed approach.
Visualizing the Demand for Various Resources as a Function of the Master Surgery Schedule: A Case Study
Authors: Jeroen Beliën, Erik Demeulemeester, Brecht Cardoen
Venue: Journal of Medical Systems (2006)

This paper presents a software system that visualizes the impact of the master surgery schedule on the demand for various resources throughout the rest of the hospital. The master surgery schedule can be seen as the engine that drives the hospital. Therefore, it is very important for decision makers to have a clear image on how the demand for resources is linked to the surgery schedule. The software presented in this paper enables schedulers to instantaneously view the impact of, e.g., an exchange of two block assignments in the master surgery schedule on the expected resource consumption pattern. A case study entailing a large Belgian surgery unit illustrates how the software can be used to assist in building better surgery schedules.
Behavioral and Electrophysiological Study of Phonological Priming between Bisyllabic Spoken Words
Authors: Nicolas Dumay, Abdelrhani Benraïss, Brian Barriol, Cécile Colin, Monique Radeau, Mireille Besson
Venue: Journal of Cognitive Neuroscience (2001)

Phonological priming between bisyllabic (CV.CVC) spoken items was examined using both behavioral (reaction times, RTs) and electrophysiological (event-related potentials, ERPs) measures. Word and pseudoword targets were preceded by pseudoword primes. Different types of final phonological overlap between prime and target were compared. Critical pairs shared the last syllable, the rime or the coda, while unrelated pairs were used as controls. Participants performed a target shadowing task in Experiment 1 and a delayed lexical decision task in Experiment 2. RTs were measured in the first experiment and ERPs were recorded in the second experiment. The RT experiment was carried out under two presentation conditions. In Condition 1 both primes and targets were presented auditorily, while in Condition 2 the primes were presented visually and the targets auditorily. Priming effects were found in the unimodal condition only. RTs were fastest for syllable overlap, intermediate for rime overlap, and slowest for coda overlap and controls that did not differ from one another. ERPs were recorded under unimodal auditory presentation. ERP results showed that the amplitude of the auditory N400 component was smallest for syllable overlap, intermediate for rime overlap, and largest for coda overlap and controls that did not differ from one another. In both experiments, the priming effects were larger for word than for pseudoword targets. These results are best explained by the combined influences of nonlexical and lexical processes, and a comparison of the reported effects with those found in monosyllables suggests the involvement of rime and syllable representations.
2-dimensional recursive orthogonal wavelet transformation
Authors: H. Yasuoka, M. Ikehara
Venue: Proceedings of the Acoustics, Speech, and Signal Processing,1994. on IEEE International Conference - Volume 04 (1994)

The design of a 2-dimensional (2-D) recursive orthogonal wavelet based on iterated filter banks is investigated. To obtain the orthogonal wavelet, we use the parallel connection of some delays and a 2-D allpass filter. In this case, a pair of digital filters with orthogonality is obtained structurally and digital filters with arbitrarily orders can be designed. Furthermore a maximum number of zeros is put at aliasing frequencies in the lowpass filter to obtain the regularity of the wavelet. Design examples of discrete scaling and wavelet functions are presented.
Performance Enhancement Technique for TCP over Mobile Ad Hoc Networks
Authors: Sung Jae Jung, Mun Gi Kim, Byung Ho Rhee
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 01 (2006)

Ad hoc networks are wireless networks of mobile nodes, self-organizing systems formed by co-operating nodes within communication range of each other that form temporary networks in which the topology rapidly changes result from the movement of mobile nodes. This frequent topology may lead to sudden packet losses and delays. So, the current implementation of TCP for the Internet is not efficient when used for mobile ad hoc networks. This is because TCP dose not show a satisfactory performance in mobile ad hoc networks due to a high BER (Bit Error Rate) and node mobility. Base TCP-Vegas does not recognize the distinction between congestion and packet losses because of transmission errors, which are current in mobile ad hoc networks. In particular, when a route is re-established it requires to be set CWND in accordance with the new route characteristic. In this paper, we propose a method to improve the TCP performance over mobile ad hoc network using new additional new module to TCP-Vegas. With this module sender node distinguishes between congestion and transmission errors it effectively adjusts the TCP's CWND and transmission rate. Simulation results using OPNET show that the proposed scheme increase TCP throughput compared with those of general TCP1
Robust Content-Dependent Photometric Projector Compensation
Authors: Mark Ashdown, Takahiro Okabe, Imari Sato, Yoichi Sato
Venue: Proceedings of the 2006 Conference on Computer Vision and Pattern Recognition Workshop (2006)

We wish to compensate for irregularities in the output of digital projectors that occur when they are used in non-ideal situations, such as those with varying surface reflectance and ambient light. We transform the image to be displayed into a compensation image that will produce the desired appearance. In contrast to previous methods, the transformation is based on both a radiometric model of the system and the content of the image. We present a five-stage framework for performing content-dependent photometric compensation, and the details of a specific implementation. The original image is converted to a perceptually-uniform space, the desired chrominance is fitted to the gamut of the projector, a luminance range is calculated within which the fitted chrominance values can be produced, the original luminance is fitted to that range, and finally the fitted values are converted to a compensation image. Our method balances strict compensation against dynamic range in the final output, so we can produce a good result even when removal of all visible spatial variation is not possible.
Multi-dimensional, paraunitary principal component filter banks
Authors: Bo Xuan, R. H. Bamberger
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1995. on International Conference - Volume 02 (1995)

This paper presents a generalization of the one-dimensional principal component filter bank (PCFB) derived by Tsatsanis (see Univ. of Virginia, Ph.D. Thesis, Sept. 1992.) to higher dimensions. Previously, the results of Tsatsanis were extended to two-dimensional signals, but this was limited to 2D signals and separable resampling operators. The filter bank discussed results in minimizing the mean squared error when only Q out of P subbands are retained. Furthermore, it is shown that the filter bank maximizes the theoretical coding gain (TCG). Simulations are presented, showing the results for reconstructing an image from only the first subband signal, demonstrating the potential of the PCFB.
A systematic approach to connecting standalone theorem provers to formal development environments
Authors: David Hemer
Venue: Proceedings of the XIII Asia Pacific Software Engineering Conference (2006)

In this paper we describe a framework that allows users of Formal Development Environments (FDEs) to prove veri-fication conditions using stand-alone theorem provers. Veri fication conditions from a given FDE are translated into an intermediate representation, then in turn translated into a form that is readable by the target theorem prover. In this paper we describe a systematic approach to the development of translators from the intermediate representation to a target theorem prover representation. The approach involves the development of a generic translator, which is instantiated for a particular target theorem prover by defining a variety of translation rules. In this paper we describe the different kinds of translation rules and illustrate their use with an example.
An Event Service Supporting Autonomic Management of Ubiquitous Systems for e-Health
Authors: Stephen Strowes, Nagwa Badr, Steven Heeps, Emil Lupu, Morris Sloman
Venue: Proceedings of the 26th IEEE International ConferenceWorkshops on Distributed Computing Systems (2006)

An event system suitable for very simple devices corresponding to a body area network for monitoring patients is presented. Event systems can be used both for self-management of the components as well as indicating alarms relating to patient health state. Traditional event systems emphasise scalability and complex event dissemination for internet based systems, whereas we are considering ubiquitous systems with wireless communication and mobile nodes which may join or leave the system over time intervals of minutes. Issues such as persistent delivery are also important. We describe the design, prototype implementation, and performance characteristics of an event system architecture targeted at this application domain.
Möbius functions and semigroup representation theory
Authors: Benjamin Steinberg
Venue: Journal of Combinatorial Theory Series A (2006)

This paper explores several applications of Möbius functions to the representation theory of finite semigroups. We extend Solomon's approach to the semigroup algebra of a finite semilattice via Möbius functions to arbitrary finite inverse semigroups. This allows us to explicitly calculate the orthogonal central idempotents decomposing an inverse semigroup algebra into a direct product of matrix algebras over group rings. We also extend work of Bidigare, Hanlon, Rockmore and Brown on calculating eigenvalues of random walks associated to certain classes of finite semigroups; again Möbius functions play an important role.
Invisibility Considered Harmful: Revisiting Traditional Principles of Ubiquitous Computing in the Context of Education
Authors: Michael Eisenberg, Ann Eisenberg, Leah Buechley, Nwanua Elumeze
Venue: Proceedings of the Fourth IEEE International Workshop on Wireless, Mobile and Ubiquitous Technology in Education (2006)

Ubiquitous computing, as a subfield of computer science, has traditionally been associated with a set of principles expressed (loosely but tellingly) with terms like transparency, invisibility, and the like: essentially, the idea is that people should be able to use ubiquitous computing artifacts while hardly being conscious that they are doing so. We argue that, as a design principle, "invisibility" has advantages in some domains; but that it has powerful, and ultimately counterproductive, connotations for educational design. We present an alternative set of potential design principles for educational ubiquitous computing, stressing values such as expressiveness, creative control, and aesthetics; and we illustrate these principles with several projects undertaken in our lab.
Using Semantic Networks for Assessment of Learners' Answers
Authors: Rainer Lutticke
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

In this paper we present a new approach for the assessment of free-text answers. We use semantic networks, based on the MultiNet paradigm, as core for the computer-based analysis of short answers given by learners. In our assessment an answer is automatically transformed in MultiNet, then compared to a reference answer, and finally the results of this analysis are reformulated in natural language. Depending on this analysis and the user model a detailed feedback is presented to the learner for the improvement of his solution. We also describe the first use, advantages, limits, and perspective of our approach.
A Mean Field EM-algorithm for Coherent Occlusion Handling in MAP-Estimation Prob
Authors: Rik Fransens, Christoph Strecha, Luc Van Gool
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 1 (2006)

This paper presents a generative model based approach to deal with occlusions in vision problems which can be formulated as MAP-estimation problems. The approach is generic and targets applications in diverse domains like model-based object recognition, depth-from-stereo and image registration. It relies on a probabilistic imaging model, in which visible regions and occlusions are generated by two separate processes. The partitioning into visible and occluded regions is made explicit by the introduction of an hidden binary visibility map, which, to account for the coherent nature of occlusions, is modelled as a Markov Random Field. Inference is made tractable by a mean field EMalgorithm, which alternates between estimation of visibility and optimisation of model parameters. We demonstrate the effectiveness of the approach with two examples. First, in a N-view stereo experiment, we compute a dense depth map of a scene which is contaminated by multiple occluding objects. Finally, in a 2D-face recognition experiment, we try to identify people from partially occluded facial images.
Improvements of space-optimized tree for visualizing and manipulating very large hierarchies
Authors: Quang Vinh Nguyen, Mao Lin Huang
Venue: Selected papers from the 2002 Pan-Sydney workshop on Visualisation - Volume 22 (2003)

This paper describes some improvements over the original Space-Optimized Tree technique for the visualization and manipulation of very large hierarchies. The new system uses an improved algorithm to calculate geometrical layouts and it also provides better navigation capability. We introduce our new layout algorithm that can make more consistence of the display than the original layout technique made. We also combine Dual View (a new focus+context technique) with the current modified semantic zooming in order to interactively navigate through the large and very large hierarchies.
Factoring based proxy signature schemes
Authors: Qingshui Xue, Zhenfu Cao
Venue: Journal of Computational and Applied Mathematics (2006)

In proxy signature schemes, original signers delegate proxy signers to sign messages on behalf of original signers. Currently, most proxy signature schemes are based on the difficulty of discrete logarithms over finite field or ellipse curve addition group. Based on the difficulty of factorings of large integers, one normal proxy signature scheme and one multi-proxy signature scheme are proposed. The security properties of strong unforgeability, verifiability, strong nonrepudiation, strong identifiability, distinguishability and prevention of misuse of proxy signing power can be fulfilled by the proposed schemes. In addition, the performance of the proposed schemes is analysed as well.
An Adaptive Caching Mechanism for Web Services
Authors: Lei Li, Chunlei Niu, Haoran Zheng, Jun Wei
Venue: Proceedings of the Sixth International Conference on Quality Software (2006)

Web services, with an emphasis on open standards and flexibility, can provide benefits over existing capital markets integration practices. However, Web services must first meet certain technical requirements including performance, security and so on. SOAP, based on Extensible Markup Language (XML), inherits not only the advantages of XML, but its relatively poor performance. This makes SOAP a poor choice for many high-performance applications. Cache is effective approach for improving the round-trip time for request-response exchanges. At present, there are lots of researches on server side cache implementation for Web Services have been presented, however, each of these studies has its own limitations and no one is the best in all situations. Focusing on these issues, this paper proposed a novel adaptive cache mechanism, which can choose an optimized cache implementation dynamically in the runtime. Moreover, this paper presented a fine-grained cache approach to obtain the further performance gain and design a cache key associated method to decrease the usage of memory. Through our experiments in this paper, we observed that our approach obtained a huge performance gain by incorporating the adaptive cache mechanism into the SOAP engine.