ppxscal/embedding_network huggingface dataset:
Fixed point error analysis of CORDIC processor based on the variance propagation
Authors: A. Sheikholeslami
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

The effects of angle approximation and founding in the CORDIC processor have been intensively studied for the determination of design parameters. However, the conventional analyses provide only the error bound which results in large discrepancy between the analysis and the actual implementation. Moreover, some of the signal processing architectures require the specification in terms of the mean squared error (MSE) as in the design specification of FFT processor for OFDM. This paper proposes a fixed point MSE analysis based on the variance propagation for more accurate error expression of CORDIC processor. It is shown that the proposed analysis can also be applied to the modified CORDIC algorithms. As an example of application, an FFT processor for OFDM using the CORDIC processor is presented. The results show close match between the analysis and simulation. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
A semantic web approach to handling soft constraints in virtual organisations
Authors: Alun Preece, Stuart Chalmers, Craig McKenzie, Jeff Z. Pan, Peter Gray
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)

In this paper we present a proposal for representing soft constraint satisfaction problems (CSPs) within the Semantic Web architecture. The proposal is motivated by the need for a service-providing agent in a virtual organisation to reason about its commitments as soft constraints. The three essential requirements addressed are: (1) the need to have constraints express commitments in terms of Semantic Web services, (2) the need to associate utility values with constraints, to reflect the relative importance of satisfying them, and (3) the need to make statements about which constraints are satisfied and violated by a given solution. The proposal builds upon previous work in defining a Semantic Web Constraint Interchange Format (CIF), which itself builds on the proposed Semantic Web Rule Language (SWRL). The paper describes an ontology for representing soft CSPs and their solutions, allowing an agent's set of commitments to be expressed as a collection of soft constraints. The ontology is an open interchange format for soft CSPs, allowing commitment to be communicated and exchanged among the members of a virtual organisation.
Experimental characterization of the transition to phase synchronization of chaos
Authors: S. Boccaletti, E. Allaria, R. Meucci, F. T. Arecchi
Venue: Proceedings of the 2003 International Conference on Physics and Control - Volume 2 (2003)

"Summary form only given". We report experimental investigation on the transition route to phase synchronization in a chaotic laser with external modulation. Such a transition is characterized by the presence of a regime of periodic phase synchronization, in which phase slips occur with maximal coherence in the phase difference between output signal and external modulation. We provide the first experimental evidence of such a regime and demonstrate that it occurs at the crossover point between two different scaling laws of the intermittent-type behavior of phase slips.
A Survey of Web Information Extraction Systems
Authors: Chia-Hui Chang, Mohammed Kayed Moheb Ramzy Girgis
Venue: IEEE Transactions on Knowledge and Data Engineering (2006)

The Internet presents a huge amount of useful information which is usually formatted for its users, which makes it difficult to extract relevant data from various sources. Therefore, the availability of robust, flexible Information Extraction (IE) systems that transform the Web pages into program-friendly structures such as a relational database will become a great necessity. Although many approaches for data extraction from Web pages have been developed, there has been limited effort to compare such tools. Unfortunately, in only a few cases can the results generated by distinct tools be directly compared since the addressed extraction tasks are different. This paper surveys the major Web data extraction approaches and compares them in three dimensions: the task domain, the automation degree, and the techniques used. The criteria of the first dimension explain why an IE system fails to handle some Web sites of particular structures. The criteria of the second dimension classify IE systems based on the techniques used. The criteria of the third dimension measure the degree of automation for IE systems. We believe these criteria provide qualitatively measures to evaluate various IE approaches.
Supercomputing interconnects
Authors: Anand Ganti, Thomas Tarman, Jason Wertz
Venue: Proceedings of the 37th conference on Winter simulation (2005)

This case study describes efforts at Sandia National Laboratories to model and simulate the interconnection network for the Red Storm supercomputer. Red Storm is a Massively Parallel Processor (MPP) machine that uses commodity processors (10,368 AMD Opterons) combined with a very high performance 3-D mesh interconnect. We consider a processor (compute node) with its associated NIC (Network Interface Card) as an atomic unit. The interconnect is built by connecting the atomic unit as a 3-D mesh with a cut-through in the Z-Axis. We model the processor, the NIC and the interconnect. We model the NIC at a functional level. Since we are only interested in the communication aspect, we model the processor as an object that can generate and receive messages according to a tunable random process. We simulate the communication pattern and evaluate the throughput and delays of the interconnect. We present in detail our modeling methodology, design, initial results, and model validation criteria.
Orienting Attention to Locations in Internal Representations
Authors: Ivan C. Griffin, Anna C. Nobre
Venue: Journal of Cognitive Neuroscience (2003)

Three experiments investigated whether it is possible to orient selective spatial attention to internal representations held in working memory in a similar fashion to orienting to perceptual stimuli. In the first experiment, subjects were either cued to orient to a spatial location before a stimulus array was presented (pre-cue), cued to orient to a spatial location in working memory after the array was presented (retro-cue), or given no cueing information (neutral cue). The stimulus array consisted of four differently colored crosses, one in each quadrant. At the end of a trial, a colored cross (probe) was presented centrally, and subjects responded according to whether it had occurred in the array. There were equivalent patterns of behavioral costs and benefits of cueing for both pre-cues and retro-cues. A follow-up experiment used a peripheral probe stimulus requiring a decision about whether its color matched that of the item presented at the same location in the array. Replication of the behavioral costs and benefits of pre-cues and retro-cues in this experiment ruled out changes in response criteria as the only explanation for the effects. The third experiment used event-related potentials (ERPs) to compare the neural processes involved in orienting attention to a spatial location in an external versus an internal spatial representation. In this task, subjects responded according to whether a central probe stimulus occurred at the cued location in the array. There were both similarities and differences between ERPs to spatial cues toward a perception versus an internal spatial representation. Lateralized early posterior and later frontal negativities were observed for both pre- and retro-cues. Retro-cues also showed additional neural processes to be involved in orienting to an internal representation, including early effects over frontal electrodes.
Support vector machines for region-based image retrieval
Authors: Feng Jing, Mingjing Li, Hong-Jiang Zhang
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

In this paper, the application of support vector machines (SVM) in relevance feedback for region-based image retrieval is investigated. Both the one class SVM as a class distribution estimator and two classes SVM as a classifier are taken into account. For the latter, two representative display strategies are studied. Since the common kernels often rely on inner product or L/sub p/ norm in the input space, they are infeasible in the region-based image retrieval systems that use variable-length representations. To resolve the issue, a new kind of kernel that is a generalization of Gaussian kernel is proposed. Experimental results on a database of 10,000 general-purpose images demonstrate the effectiveness and robustness of the proposed approach.
Evaluation of SEU and crosstalk effects in network-on-chip switches
Authors: Arthur Pereira Frantz, Fernanda Lima Kastensmidt, Luigi Carro, Érika Cota
Venue: Proceedings of the 19th annual symposium on Integrated circuits and systems design (2006)

As the complexity of designs increases and the technology scales down into the deep sub-micron domain, devices and interconnections are subject to new types of malfunctions and failures. This work intends to evaluate the effect of Single Event Upsets (SEUs) and crosstalk faults in a Network-on-Chip switch by performing fault injection simulations, allowing an accurate analysis of the impact of these faults over the switch service. The results show that such faults might affect the switch behavior, with errors ranging from simple loss of packets up to the permanent interruption of the switch service.
Computing Horn Strong Backdoor Sets Thanks to Local Search
Authors: Lionel Paris, Richard Ostrowski, Pierre Siegel, Lakhdar Sais
Venue: Proceedings of the 18th IEEE International Conference on Tools with Artificial Intelligence (2006)

In this paper a new approach for computing Strong Backdoor sets of boolean formula in conjunctive normal form (CNF) is proposed. It makes an original use of local search techniques for finding an assignment leading to a largest renamable Horn sub-formula of a given CNF. More precisely, at each step, preference is given to variables such that when assigned to the opposite value lead to the smallest number of remaining non- Horn clauses. Consequently, if no positive or non Horn clauses remain in the formula, our approach answer the satisfiability of the original formula; otherwise, a smallest non-Horn sub-formula is used to extract the set of variables (Strong Backdoor) such that when assigned leads to a tractable sub-formula. Branching on the variables of the Strong Backdoor set leads to significant improvements of Zchaff SAT solver with respect to many real worlds SAT instances.
Distributed and Learner Adaptive e-Learning Environment with Use of Web Services
Authors: Yasuhisa Tamura, Takeshi Yamamuro, Toshio Okamoto
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

Web Services based e-learning architecture is proposed, in which various types of functionally distributed servers communicate each other and share learning-related information. These servers are assigned functions of archiving information directory, learning contents, learner information, and learning sequence of contents. On this architecture, the authors designed a function to modify sequence of learning materials automatically due to learner's learning style. This function provides learner-adapted contents, which is incapable of conventional e-learning architecture.
Detection and Tracking of Multiple Metallic Objects in Millimetre-Wave Images
Authors: C. D. Haworth, Y. Saint-Pern, D. Clark, E. Trucco, Y. R. Petillot
Venue: International Journal of Computer Vision (2007)

In this paper we present a system for the automatic detection and tracking of metallic objects concealed on moving people in sequences of millimetre-wave (MMW) images. The millimetre-wave sensor employed has been demonstrated for use in covert detection because of its ability to see through clothing, plastics and fabrics.The system employs two distinct stages: detection and tracking. In this paper a single detector, for metallic objects, is presented which utilises a statistical model also developed in this paper. The second stage tracks the target locations of the objects using a Probability Hypothesis Density filter. The advantage of this filter is that it has the ability to track a variable number of targets, estimating both the number of targets and their locations. This avoids the need for data association techniques as the identities of the individual targets are not required. Results are presented for both simulations and real millimetre-wave image test sequences demonstrating the benefits of our system for the automatic detection and tracking of metallic objects.
Neural Evidence for Representation-Specific Response Selection
Authors: Eric H. Schumacher, Puni A. Elston, Mark D'esposito
Venue: Journal of Cognitive Neuroscience (2003)

Response selection is the mental process of choosing representations for appropriate motor behaviors given particular environmental stimuli and one's current task situation and goals. Many cognitive theories of response selection postulate a unitary process. That is, one central response-selection mechanism chooses appropriate responses in most, if not all, task situations. However, neuroscience research shows that neural processing is often localized based on the type of information processed. Our current experiments investigate whether response selection is unitary or stimulus specific by manipulating response-selection difficulty in two functional magnetic resonance imaging experiments using spatial and nonspatial stimuli. The same participants were used in both experiments. We found spatial response selection involves the right prefrontal cortex, the bilateral premotor cortex, and the dorsal parietal cortical regions (precuneus and superior parietal lobule). Nonspatial response selection, conversely, involves the left prefrontal cortex and the more ventral posterior cortical regions (left middle temporal gyrus, left inferior parietal lobule, and right extrastriate cortex). Our brain activation data suggest a cognitive model for response selection in which different brain networks mediate the choice of appropriate responses for different types of stimuli. This model is consistent with behavioral research suggesting that response-selection processing may be more flexible and adaptive than originally proposed.
Fast Block Center Weighted Hadamard Transform
Authors: Moon Ho Lee, Xiao-Dong Zhang
Venue: Proceedings of the International Conference on Systems and Networks Communication (2006)

Motivated by the Hadamard transforms and center weighted Hadamard transforms, a new class of block center weighted Hadamard transforms (BCWHT) are proposed, which weights the region of mid-spatial frequencies of the signal more than the Hadamard transform. Based on the Kronecker product, directed sum operations, the identity matrix and recursive relations, the proposed one and two dimensions fast block center weighted Hadamard transforms algorithms through sparse matrix factorization are simply obtained.
Minerals: using data mining to detect router misconfigurations
Authors: Franck Le, Sihyung Lee, Tina Wong, Hyong S. Kim, Darrell Newcomb
Venue: Proceedings of the 2006 SIGCOMM workshop on Mining network data (2006)

Recent studies have shown that router misconfigurations are common and have dramatic consequences for the operations of networks. Not only can misconfigurations compromise the security of a single network, they can even cause global disruptions in Internet connectivity. Several solutions have been proposed that can detect a number of problems in real configuration files. However, these solutions share a common limitation: they are rule-based. Rules are assumed to be known beforehand, and violations of these rules are deemed misconfigurations. As policies typically differ among networks, rule-based approaches are limited in the scope of mistakes they can detect. In this paper, we address the problem of router misconfigurations using data mining. We apply association rules mining to the configuration files of routers across an administrative domain to discover local, network-specific policies. Deviations from these local policies are potential misconfigurations. We have evaluated our scheme on configuration files from a large state-wide network provider, a large university campus and a high-performance research network, and found promising results. We discovered a number of errors that were confirmed and later corrected by the network engineers. These errors would have been difficult to detect with current rule-based approaches.
A Pattern for Adaptive Behavior in Safety-Critical, Real-Time Middleware
Authors: Tanya L. Crenshaw, C. L. Robinson, Hui Ding, P. R. Kumar, Lui Sha
Venue: Proceedings of the 27th IEEE International Real-Time Systems Symposium (2006)

Patterns are a valuable method for communicating software engineering expertise about proven solutions for common problems. This paper evaluates the use of domainindependent patterns in a case study of Etherware, a middleware for networked control with a real-time, safety-critical applications model. The case study illustrates the positive and negative impact that four existing patterns have on availability, reliability, and robustness for real-time, safety-critical systems. In particular, we observe Etherware's specialized usage of the Filter pattern, confirm this usage among other middleware technologies, and subsequently present the Adaptive Control Filter, a design pattern for real-time, safety-critical middleware which can mitigate timing dependencies in networked control.
A simple and intuitive simulation tool for analyzing emergency department operations
Authors: David Sinreich, Yariv N. Marmor
Venue: Proceedings of the 36th conference on Winter simulation (2004)

In recent years hospitals have been vigorously searching for ways to reduce costs and improve productivity. One tool, simulation, is now widely accepted as an effective method for assisting management in evaluating different operational alternatives. It can help improve existing Emergency Departments (EDs) and assist in planning and designing new EDs. In order to increase the acceptance of simulation in healthcare systems in general and EDs in particular, hospital management should be directly involved in the development of these projects. Such involvement will also bolster the model's credibility. In addition, it is important to simplify simulation processes as much as is reasonably possible and use visual aids or animation that will heighten users' confidence in the model's ability. This study lays the foundation for the development of a simulation tool which is general, flexible, intuitive, simple to use and contains default values for most of the system's parameters.
Control of an Industrial Robot using Acceleration Feedback
Authors: Eric Dumetz, Jean-Yves Dieulot, Pierre-Jean Barre, Frédéric Colas, Thomas Delplace
Venue: Journal of Intelligent and Robotic Systems (2006)

A controller using acceleration feedback has been applied to a flexible robot for which the position and velocity of the load are not measured. It is shown that acceleration feedback allows an exact tracking of the motor position, irrespective of the non-linear flexibilities of the axes and of the measurement disturbances. This easy-to-tune algorithm whose main control parameters are the modal masses of the motor and load part, and only consists of a positive acceleration feedback plus a PD controller, has been validated on an industrial robot with orthogonal axes.
A robust statistic method for classifying color polarity of video text
Authors: Jiqiang Song, Min Cai, M. R. Lyu
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

Video text extraction and recognition are prerequisite tasks for video indexing and retrieval. Color polarity classification of video text is very important to these tasks. Most existing text extraction methods assume that the text color is always light (or dark). Obviously, this assumption restricts the application of these methods to some specific domains. Only a few methods can detect the color polarity on condition that the background is clear. However, many real video texts have various appearances and complex backgrounds that existing methods cannot handle. This paper proposes a statistic color polarity classification method that is robust to various background complexities, font styles, stroke widths, and languages. We discover the intrinsic relationships between text edges and background edges, and then develop an efficient measurement to detect the color polarity. The experimental results show that the proposed method achieves a much higher accuracy, 98.5%, than existing methods.
Nonparametric Priors on the Space of Joint Intensity Distributions for Non-Rigid Multi-Modal Image Registration
Authors: Daniel Cremers, Christoph Guetter, Chenyang Xu
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 2 (2006)

The introduction of prior knowledge has greatly enhanced numerous purely low-level driven image processing algorithms. In this work, we focus on the problem of nonrigid image registration. A number of powerful registration criteria have been developed in the last decade, most prominently the criterion of maximum mutual information. Although this criterion provides for good registration results in many applications, it remains a purely low-level criterion. As a consequence, registration results will deteriorate once this low-level information is corrupted, due to noise, partial occlusions or missing image structure. In this paper, we will develop a Bayesian framework that allows to impose statistically learned prior knowledge about the joint intensity distribution into image registration methods. The prior is given by a kernel density estimate on the space of joint intensity distributions computed from a representative set of pre-registered image pairs. This nonparametric prior accurately models previously learned intensity relations between various image modalities and slice locations. Experimental results demonstrate that the resulting registration process is more robust to missing low-level information as it favors intensity correspondences statistically consistent with the learned intensity distributions.
The Integration and Interoperability Issues of Legacy and Distributed Systems
Authors: S. Kami Makki
Venue: Proceedings of the Seventh International Conference on Web-Age Information Management Workshops (2006)

An important issue of distributed systems is interoperability. Lack of interoperability between distributed systems is a common problem with current and legacy applications. Since the legacy applications represent a major investment and for the most part can not be abandoned. Enterprises are looking for solutions that enable the integration of the legacy environments with the new breed of distributed applications, as well as the integration between their existing applications caused either by mergers and acquisitions, or a company's desire to move into a new and uncharted business activity. This paper provides an in depth analysis of legacy systems integration. It presents an analysis of distributed systems concepts and design as seen from the perspective of the integration of a monolithic legacy systems into a distributed systems, and it concludes that distributed systems protocols and architecture must be tailored to various levels within the legacy systems in order for an integration project to succeed.