ppxscal/embedding_network huggingface dataset:
Coexistence Mechanisms for Bluetooth SCO Link and IEEE 802.11 WLAN
Authors: Tsung-Chuan Huang, Shao-Hsien Chiang
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 02 (2006)

Wireless network systems, such as IEEE 802.11 wireless local area networks (WLANs) and Bluetooth, are increasingly constructed in our surrounding environment. Although devices running these two wireless systems operate with different technologies, they both work in the 2.4 GHz ISM (Industrial, Scientific, and Medical) band, and therefore lead to interference. The problem of Bluetooth interfering with a WLAN is particularly serious with a Bluetooth device located in an area with more than one overlapping WLAN. Interference is not a significant problem if it only degrades data throughput. However, it is unacceptable if it causes disconnection of the Bluetooth SCO link (i.e., voice connection). This study presents mechanisms to sustain the quality of Bluetooth SCO link, under the interference, with only at a minor cost of WLAN's data throughput.
Self-Organizing wireless sensor networks in action
Authors: John A. Stankovic
Venue: Proceedings of the 12th ACM SIGKDD international conference on Knowledge discovery and data mining (2006)

Wireless sensor networks (WSN) composed of large numbers of small devices that self-organize are being investigated for a wide variety of applications. Two key advantages of these networks over more traditional sensor networks are that they can be dynamically and quickly deployed, and that they can provide fine-grained sensing. Applications, such as emergency response to natural or manmade disasters, detection and tracking, and fine grained sensing of the environment are key examples of applications that can benefit from these types of WSN. Current research for these systems is widespread. However, many of the proposed solutions are developed with simplifying assumptions about wireless communication and the environment, even though the realities of wireless communication and environmental sensing are well known. Many of the solutions are evaluated only by simulation. In this talk I describe a fully implemented system consisting of a suite of more than 30 synthesized protocols. The system supports a power aware surveillance, tracking and classification application running on 203 XSM motes and evaluated in a realistic, large-area environment. Technical details and evaluations are presented. I end with a discussion of opportunities and problems for data mining related to WSN.
Position paper on: standard operating system interfaces
Authors: Jack Cowan
Venue: ACM SIGSMALL Newsletter (1981)

The computer industry in general, and the software portion of that industry specifically, has expended intense effort during the 1970's developing systems which are portable across hardware environments. The initial efforts were in the area of language standardization. It was found that the same language implemented across multiple hardware environments was not consistent. This diversity was in part created by software designers taking maximum advantage of a specific hardware environment. However, to a great extent the differences within a particular language implementation were generated by the fact that software designers were designing not for a specific piece of hardware but for a virtual machine environment which was defined by the operating system and the hardware in concert with each other.
Guest Editors' Introduction: Data Surveillance
Authors: Simson Garfinkel, Michael D. Smith
Venue: IEEE Security and Privacy (2006)

The guest editors discuss data surveillance. Proponents hope that data surveillance technology will be able to anticipate and prevent terrorist attacks, detect disease outbreaks, and allow for detailed social science research--all without the corresponding risks to personal privacy because machines, not people, perform the surveillance.
Learning a New Statistical Shape Prior Model for Object Detection by Geodesic Active Contours
Authors: Wen Fang, Kap Luk Chan
Venue: Proceedings of the IEEE International Conference on Video and Signal Based Surveillance (2006)

A new statistical shape prior model is proposed in this paper which is incorporated into geodesic active contours for robust object detection. The object shapes that undergo nonlinear deformable changes are assumed to lie in a low dimensional feature subspace and form clusters after a nonlinear mapping. They are approximated by a probabilistic density model to explore the structure of data distribution. The obtained probability is treated as a shape energy term and is incorporated into geodesic active contour equation to constrain the further curve evolution process. This shape prior model is based on a more sophisticated statistical learning of the training data distribution and thus is more robust in presence of occlusions and cluttered background. Experiments demonstrate its promising detection performance for the intended tasks.
Biases in Attentional Orientation and Magnitude Estimation Explain Crossover: Neglect is a Disorder of Both
Authors: Mark Mennemeier, Christopher A. Pierce, Anjan Chatterjee, Britt Anderson, George Jewell, Rachael Dowler, Adam J. Woods, Tannahill Glenn, Victor W. Mark
Venue: Journal of Cognitive Neuroscience (2005)

Crossover refers to a pattern of performance on the line bisection test in which short lines are bisected on the side opposite the true center of long lines. Although most patients with spatial neglect demonstrate crossover, contemporary theories of neglect cannot explain it. In contrast, we show that blending the psychophysical construct of magnitude estimation with neglect theory not only explains crossover, but also addresses a quantitative feature of neglect that is independent of spatial deficits. We report a prospective validation study of the orientation/estimation hypothesis of crossover. Forty subjects (17 patients with and without neglect following unilateral brain injury and 23 normal controls) completed four experiments that examined crossover using line bisection, line bisection with cueing, and reproducing line lengths from both memory and a standard. Replicating earlier findings, all except one subject group exhibited crossover on the standard line bisection test, all groups showed a spontaneous preference to orient attention to one end of the lines, and all groups overestimated the length of short lines and underestimated long lines. Biases in attentional orientation and magnitude estimation are exaggerated in patients with neglect. The truly novel finding of this study occurred when, after removing the line from the bisection task, the direction of crossover was completely reversed in all subject groups depending on where attention was oriented. These findings are consistent with our hypothesis of crossover: (1) crossover is a normal component of performance on line bisection; (2) crossover results from the interplay of biases in attentional orientation and magnitude estimation; and (3) attentional orientation predicts the direction of crossover, whereas a disorder of magnitude estimation, not previously emphasized in neglect, accounts for the quantitative changes in length estimation that make crossover more obvious in neglect subjects. Paradoxically, we observed that the traditional line bisection test is suboptimal for exploring crossover because lines elicit spontaneous orientation responses from subjects that confound experimental manipulations of attention. We conclude that attentional orientation and magnitude estimation are necessary and sufficient to explain crossover and that bias in magnitude estimation is a core component of neglect.
Passive verification of the strategyproofness of mechanisms in open environments
Authors: Laura Kang, David C. Parkes
Venue: Proceedings of the 8th international conference on Electronic commerce: The new e-commerce: innovations for conquering current barriers, obstacles and limitations to conducting successful business on the internet (2006)

Consider an open infrastructure in which anyone can deploy mechanisms to support automated decision making and coordination amongst self-interested computational agents. Strategyproofness is a central property in the design of such mechanisms, allowing participants to maximize their individual benefit by reporting truthful private information about preferences and capabilities and without modeling or reasoning about the behavior of other agents. But, why should participants trust that a mechanism is strategyproof? We address this problem, proposing and describing a passive verifier, able to monitor the inputs and outputs of mechanisms and verify the strategyproofness, or not, of a mechanism. Useful guarantees are available to participants before the behavior of the mechanism is completely known, and metrics are introduced to provide a measure of partial verification. Experimental results demonstrate the effectiveness of our method.
Balancing bias and variance in the optimization of simulation models
Authors: Christine S. M. Currie, Russell C. H. Cheng
Venue: Proceedings of the 37th conference on Winter simulation (2005)

We consider the problem of identifying the optimal point of an objective in simulation experiments where the objective is measured with error. The best stochastic approximation algorithms exhibit a convergence rate of n&minus;1/6 which is somewhat different from the n&minus;1/2 rate more usually encountered in statistical estimation. We describe some simple simulation experimental designs that emphasize the statistical aspects of the process. When the objective can be represented by a Taylor series near the optimum, we show that the best rate of convergence of the mean square error is when the variance and bias components balance each other. More specifically, when the objective can be approximated by a quadratic with a cubic bias, then the fastest decline in the mean square error achievable is n&minus;2/3. Some elementary theory as well as numerical examples will be presented.
Diagnosis of TCP overlay connection failures using bayesian networks
Authors: George J. Lee, Lindsey Poole
Venue: Proceedings of the 2006 SIGCOMM workshop on Mining network data (2006)

When failures occur in Internet overlay connections today, it is difficult for users to determine the root cause of failure. An overlay connection may require TCP connections between a series of overlay nodes to succeed, but accurately determining which of these connections has failed is difficult for users without access to the internal workings of the overlay. Diagnosis using active probing is costly and may be inaccurate if probe packets are filtered or blocked. To address this problem, we develop a passive diagnosis approach that infers the most likely cause of failure using a Bayesian network modeling the conditional probability of TCP failures given the IP addresses of the hosts along the overlay path. We collect TCP failure data for 28.3 million TCP connections using data from the new Planetseer overlay monitoring system and train a Bayesian network for the diagnosis of overlay connection failures. We evaluate the accuracy of diagnosis using this Bayesian network on a set of overlay connections generated from observations of CoDeeN traffic patterns and find that our approach can accurately diagnose failures.
Generation of problems, answers, grade, and feedback---case study of a fully automated tutor
Authors: Amruth N. Kumar
Venue: Journal on Educational Resources in Computing (JERIC) (2005)

Researchers and educators have been developing tutors to help students learn by solving problems. The tutors vary in their ability to generate problems, generate answers, grade student answers, and provide feedback. At one end of the spectrum are tutors that depend on hand-coded problems, answers, and feedback. These tutors can be expected to be pedagogically effective, since all the problem-solving content is carefully hand-crafted by a teacher. However, their repertoire is limited. At the other end of the spectrum are tutors that can automatically generate problems, answers, and feedback. They have an unlimited repertoire, but it is not clear that they are effective in helping students learn. Most extant tutors lie somewhere along this spectrum.In this article we examine the feasibility of developing a tutor that can automatically generate problems, generate answers, grade student answers, and provide feedback. We investigate whether such a tutor can help students learn. For our study, we considered a tutor for our Programming Languages course, which covers static and dynamic scope (i.e., static scope of variables and procedures, dynamic scope of variables, and static and dynamic referencing environment of procedures in the context of a language that permits nested procedure definitions). The tutor generates simple and complex problems on each of these five topics, solves the problems, grades the students' answers, and provides feedback about incorrect and missed answers. Our evaluation over two semesters shows that the feedback provided by the tutor helps improve student learning.
Reliability - Security Model
Authors: Norman F. Schneidewind
Venue: Proceedings of the 11th IEEE International Conference on Engineering of Complex Computer Systems (2006)

This paper includes the conditional probability of security failures given the occurrence of reliability failures. To our knowledge, this is the first research to perform this type of integration of reliability and security. It was necessary for us to use hypothetical but realistic probability distributions and parameters because, unfortunately, cyber attack data is not publicly available. In our model, we calculate error rates between predicted and actual values of reliability and security quantities. We provide a discussion of the policy implications for mitigating reliability and security problems based on model results. Our approach is most applicable to critical infrastructure systems.
Linear Regression Methods to Predict Interval-Valued Data
Authors: Eufrasio A. Lima Neto, Francisco de A. T. de Carvalho, Lucas X. T. Bezerra
Venue: Proceedings of the Ninth Brazilian Symposium on Neural Networks (2006)

This paper introduce a new criterion and two new linear regression methods to predict interval-valued data. The proposed approaches consist in a new point of view to study the relationship between the midpoints and the ranges of the interval-valued variables. The evaluation of the proposed prediction methods is based on the average behaviour of the root mean squared error and the square of the correlation coefficient in the framework of a Monte Carlo experiment in comparison with the method proposed by [3].
An Application of Semantic Annotations to Design Errors
Authors: Injae Shin, Sanghee Kim, Jerry Busby, Ralph E. Hibberd, Chris A. McMahon
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 01 (2006)

As current engineered systems (e.g. aviation systems) have been equipped with automated and computer-based artefacts, human-system interaction (e.g. human computer interaction) has been an important issue. Design errors that are attributable to human-system interaction failures are not pure engineering design issues, but a multidisciplinary subject with related other areas such as management, psychology, physiology or ergonomics. To identify such design errors (called design-induced errors) in accident reports is important for designing more reliable systems. However, the lack of precise definitions of the concept of design-induced error and the diversity of expression of such failures make it difficult to retrieve relevant documents from accident reports. This paper describes how an ontology and annotation scheme can help to overcome such limitations. Engineering designers can be assisted by the developed ontology and annotation scheme to reason on the issues of design induced error.
A numerical scheme for the integration of the Vlasov-Poisson system of equations, in the magnetized case
Authors: Francesco Valentini, Pierluigi Veltri, André Mangeney
Venue: Journal of Computational Physics (2005)

We present a numerical algorithm for the solution of the Vlasov-Poisson system of equations, in the magnetized case. The numerical integration is performed using the well-known ''splitting'' method in the electrostatic approximation, coupled with a finite difference upwind scheme; finally the algorithm provides second order accuracy in space and time. The cylindrical geometry is used in the velocity space, in order to describe the rotation of the particles around the direction of the external uniform magnetic field. Using polar coordinates, the integration of the Vlasov equation is very simplified in the velocity space with respect to the cartesian geometry, because the rotation in the velocity cartesian space corresponds to a translation along the azimuthal angle in the cylindrical reference frame. The scheme is intrinsically symplectic and significatively simpler to implement, with respect to a cartesian one. The numerical integration is shown in detail and several conservation tests are presented, in order to control the numerical accuracy of the code and the time evolution of the entropy, strictly related to the filamentation problem for a kinetic model, is discussed.
On the Maximization of (not necessarily) Convex Functions on Convex Sets
Authors: C. Zălinescu
Venue: Journal of Global Optimization (2006)

The global solutions of the problem of maximizing a convex function on a convex set were characterized by several authors using the Fenchel (approximate) subdifferential. When the objective function is quasiconvex it was considered the differentiable case or used the Clarke subdifferential. The aim of the present paper is to give necessary and sufficient optimality conditions using several subdifferentials adequate for quasiconvex functions. In this way we recover almost all the previous results related to such global maximization problems with simple proofs.
Combined Lesk-Based Method for Words Senses Disambiguation
Authors: Yoel Ledo-Mezquita, Grigori Sidorov, Vicente Cubells
Venue: Proceedings of the 15th International Conference on Computing (2006)

Word sense disambiguation (WSD) is a linguistically-based mechanism for defining automatically the correct sense of a word in the context. Lesk-based methods use context information for WDS. In this paper, we propose a method of word sense disambiguation based on the combination of the original Lesk method and the simplified one with additional application of large lexical resources, like synonym dictionaries, ontologies, etc., for calculations of sense plausibility. We present experimental results that show that our method has better precision than the baseline Lesk-based methods.
Make-to-stock systems with backorders: IPA gradients
Authors: Yao Zhao, Benjamin Melamed
Venue: Proceedings of the 36th conference on Winter simulation (2004)

We consider single-stage, single-product Make-to-Stock systems with random demand and random service (production) rate, where demand shortages at the inventory facility are backordered. The Make-to-Stock system is modeled as a stochastic fluid model (SFM), in which the traditional discrete arrival, service and departure stochastic processes are replaced by corresponding stochastic fluid-flow rate processes. IPA (Infinitesimal Perturbation Analysis) gradients of various performance metrics are derived with respect to parameters of interest (here, base-stock level and production rate), and are showed to be unbiased and easy to compute. The (random) IPA gradients are obtained via sample path analysis under very mild assumptions, and are inherently nonparametric in the sense that no specific probability law need be postulated. The formulas derived can be used in simulation, as well as in real-life systems.
Spatiospectral Concentration on a Sphere
Authors: Frederik J. Simons, F. A. Dahlen, Mark A. Wieczorek
Venue: SIAM Review (2006)

We pose and solve the analogue of Slepian&apos;s time-frequency concentration problem on the surface of the unit sphere to determine an orthogonal family of strictly bandlimited functions that are optimally concentrated within a closed region of the sphere or, alternatively, of strictly spacelimited functions that are optimally concentrated in the spherical harmonic domain. Such a basis of simultaneously spatially and spectrally concentrated functions should be a useful data analysis and representation tool in a variety of geophysical and planetary applications, as well as in medical imaging, computer science, cosmology, and numerical analysis. The spherical Slepian functions can be found by solving either an algebraic eigenvalue problem in the spectral domain or a Fredholm integral equation in the spatial domain. The associated eigenvalues are a measure of the spatiospectral concentration. When the concentration region is an axisymmetric polar cap, the spatiospectral projection operator commutes with a Sturm--Liouville operator; this enables the eigenfunctions to be computed extremely accurately and efficiently, even when their area-bandwidth product, or Shannon number, is large. In the asymptotic limit of a small spatial region and a large spherical harmonic bandwidth, the spherical concentration problem reduces to its planar equivalent, which exhibits self-similarity when the Shannon number is kept invariant.
Collaborative Change Detection of DDoS Attacks on Community and ISP Networks
Authors: Yu Chen, Kai Hwang
Venue: Proceedings of the International Symposium on Collaborative Technologies and Systems (2006)

A community network often operates within the same ISP (Internet Service Provider) domain or the network is administered by a virtual organization spanning across multiple network domains with an established trust relationship. To counter DDoS (distributed denial-of-service) attacks in such a federated network environment, the routers can work cooperatively to raise early warning to avoid catastrophic damages. This paper proposes a collaborative architecture to detect DDoS flooding attacks. The scheme appeals, in particular, to protect networked resource centers that work as a collaboration Grid. By monitoring the distribution of suspicious traffic changes over a number of attack-transit routers, we developed a new Change-Aggregation Tree (CAT) mechanism to enable early detection of DDoS attacks on community networks. We want to detect flooding attacks as early as possible. Here, we report preliminary NS-2 simulation results on a singledomain ISP core network to prove the effectiveness of the new collaborative CAT architecture for DDoS defense. The simulated system achieved a detection rate as high as 95% with less than 1% of false positive alarms. Extensions of this architecture to cross-domain DDoS defense are discussed with further research challenges identified.
The Role of MPEG-7 in semantic Annotation and the Cross-Media Publishing Process
Authors: Tobias Burger, Georg Guntner, Erich Gams
Venue: Proceedings of the Second International Conference on Automated Production of Cross Media Content for Multi-Channel Distribution (2006)

During the development of a knowledge-based audio- visual information system the authors of this article defined a conceptual system architecture based on MPEG-7 as the general description scheme for the media assets in the middleware. This concept was not only used to achieve a high abstraction and independence of the underlying media asset management system, it was also and primarily used as the basis of a semantic indexing process. Based on lightweight ontologies the descriptions of the media assets were associated with semantic concepts. Semantically annotated MPEG-7 assets were then propagated to the presentation layer, thus allowing the implementation of a variety of publication scenarios, including crossmedia scenarios for the creation of concise video summaries.