ppxscal/embedding_network huggingface dataset:
Discovering Unrevealed Properties of Probability Estimation Trees: On Algorithm Selection and Performance Explanation
Authors: Kun Zhang, Wei Fan, Bill Buckles, Xiaojing Yuan, Zujia Xu
Venue: Proceedings of the Sixth International Conference on Data Mining (2006)

There has been increasing interest to design better probability estimation trees, or PETs, for ranking and probability estimation. Capable of generating class membership probabilities, PETs have been shown to be highly accurate and flexible for many difficult problems, such as cost-sensitive learning and matching skewed distributions. There are a large number of PET algorithms available, and about ten of them are well-known. This large number provides an advantage, but it also creates confusion in practice. One would ask "given a new dataset, which algorithm to choose and what performance to expect and not to expect? What are the reasons to explain either good or bad performance under different situations?" In this paper, we systematically, for the first time, answer these important questions by conducting a large-scale empirical comparison of five popular PETs by examining their AUC, MSE and error rate "learning curves" (instead of training-test split based cross-validation). Using the maximum AUC achieved by any of the evaluated probability estimation tree algorithms, we demonstrate that the preference of a probability estimation tree on different evaluation metrics can be accurately characterized by the "signal-noise separability" of the dataset, as well as some other observable statistics of the dataset explained further in the paper. Moreover, in order to understand their relative performance, many important and previously unrevealed properties of each PET's mechanism and heuristics are analyzed and evaluated. Importantly, a practical guide for choosing the most appropriate PET algorithm given a new data mining problem is provided.
Modelling the links between social commitments and individual intentions
Authors: Philippe Pasquier, Brahim Chaib-draa
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

Social commitments have been increasingly used to model inter-agent dependencies and normative aspects of multi-agent systems such as the semantics of agent communication. However, current cognitive agent architecture rest on a formalization of private mental states. In this paper, we propose a modelling of the links between private mental states resulting in individual intentions and social commitments.
Neural Mechanisms of Cognitive Control: An Integrative Model of Stroop Task Performance and fMRI Data
Authors: Seth A. Herd, Marie T. Banich, Randall C. O'reilly
Venue: Journal of Cognitive Neuroscience (2006)

We address the connection between conceptual knowledge and cognitive control using a neural network model. This model extends a widely held theory of cognitive control [Cohen, J. D., Dunbar, K., & McClelland, J. L. On the control of automatic processes: A parallel distributed processing model of the Stroop effect. Psychological Review, 97, 332&ndash;361, 1990] so that it can explain new empirical findings. Leveraging other computational modeling work, we hypothesize that representations used for task control are recruited from preexisting representations for categories, such as the concept of color relevant to the Stroop task we model here. This hypothesis allows the model to account for otherwise puzzling fMRI results, such as increased activity in brain regions processing to-be-ignored information. In addition, biologically motivated changes in the model's pattern of connectivity show how global competition can arise when inhibition is strictly local, as it seems to be in the cortex. We also discuss the potential for this theory to unify models of task control with other forms of attention.
Multiobjective simulation optimization using an enhanced genetic algorithm
Authors: Hamidreza Eskandari, Luis Rabelo, Mansooreh Mollaghasemi
Venue: Proceedings of the 37th conference on Winter simulation (2005)

This paper presents an improved genetic algorithm approach, based on new ranking strategy, to conduct multi-objective optimization of simulation modeling problems. This approach integrates a simulation model with stochastic nondomination-based multiobjective optimization technique and genetic algorithms. New genetic operators are introduced to enhance the algorithm performance of finding Pareto optimal solutions and its efficiency in terms of computational effort. An elitism operator is employed to ensure the propagation of the Pareto optimal set, and a dynamic expansion operator to increase the population size. An importation operator is adapted to explore some new regions of the search space. Moreover, new concepts of stochastic and significant dominance are introduced to improve the definition of dominance in stochastic environments.
What will we do with all that bandwidth?
Authors: Fred Maryanski
Venue: ACM SIGSMALL Newsletter (1982)

Let's skip the business (except for a few items) and do something technical this time. You have all heard about the recent developments in local network technology that will permit to communicate between machines at rates of 10 Mega bits per second or higher. On first blush, these high speed interconnections might be viewed as THE breakthrough that will allow "true" distributed computing without painful delays. However, more careful consideration of the problem leads to a slight dampening of our fervor. First, we must realize tht a high speed interconnection will not make computers or disks run any faster than they do at the moment. Many small systems are simply not capable of utilizing a 10 Mbit link even if their entire capacity were devoted to reading or writing packets. With more powerful CPU's, it is possible to construct a system that will transfer data between machines at close to the speed of the disks. Several file transfer protocols have been implemented which operate close to disk speed, but which utilize only a small percentage of the communication bandwidth. Once the disk becomes the limiting factor, extra bandwith on the communications link can not improve performance.
An author tool based on SEM-HP for the creation and evolution of adaptive hypermedia systems
Authors: Fernando Molina-Ortiz, Nuria Medina-Medina, Lina García-Cabrera
Venue: Workshop proceedings of the sixth international conference on Web engineering (2006)

This paper presents JSEM-HP, an author tool for the development of semantic, adaptive and evolutionary hypermedia systems based on the model SEM-HP. The proposed development process has four iterative phases, associated to four interacting subsystems: memorization, in which the author creates a specific kind of semantic network that gives semantic coherence to the information offered to the user; presentation, which allows to select different subsets of the semantic net; navigation, which permits to define an order to navigate the items according to their semantic relations; and learning, which takes care of user modeling and adaptation. The tool supports the evolution of the systems created with it, assuring that changes made in a subsystem keep this subsystem and the whole system in a consistent state. The user adaptation supported by the tool allows the semantic net that is offered to the user to be dynamically adapted to the user knowledge, so he will not access the information he is not ready to understand, and he will have awareness of his process of learning.
Anonymity and independence in multiparty protocols
Authors: Daniele Micciancio
Venue:  (2006)

Electronic voting systems, chat rooms, and electronic auctions are well-known examples of systems that involve many people interacting at the same time in order to achieve a goal: cast a vote, discuss political ideas, and bid for an item. Yet, some security goals of these multi-party protocols have not been carefully examined as they should. For example, how different is protecting the anonymity of the sender---as in an electronic election---versus protecting the anonymity of both the sender and the receiver---as in a political chat room? Or, can online surveys guarantee that participants do not influence each other's answers? This dissertation studies two of these properties: anonymity and independence of inputs. We first revisit the problem of anonymous communication, in which users wish to send messages to each other without revealing their identities. We propose a novel framework to organize and compare anonymity definitions. In this framework, we present simple and practical definitions for anonymous channels in the context of computational indistinguishability. The notions capture the intuitive properties of several known types of anonymous channels, and also model practical scenarios where information is leaked in the system. We also compare these notions showing how stronger notions can be built from weaker ones in a provably optimal way. With these tools, we revisit the security of previous popular anonymous channels protocols. In applications where multiple senders can broadcast messages at the same time (like electronic auctions or elections), it is often important to enforce the simultaneous transmission of messages, so that no sender can decide its broadcast message based on the values broadcast by other players. In the second part of the dissertation, we study the definitions of independence (or Simultaneous Broadcast) proposed in the literature, obtaining a full characterization of their applicability and relative strength. In particular, we show that the latest definition, under which the most (round) efficient solution was proven secure, is strictly weaker than the previous definitions. We thus reopen the problem of either proving the efficient solution satisfies the strongest definition of security or finding an alternative efficient protocol that does so. We conclude by addressing this last problem. We present a definition of simultaneous broadcast under the Universally Composable framework, and show that this stronger notion can be achieved by a computationally efficient, constant-round construction. Our construction builds on an existent adaptive verifiable secret sharing scheme, and does not resort to generic zero-knowledge proofs or commitment schemes present in previous solutions.
A Magnetic Stimulation Examination of Orthographic Neighborhood Effects in Visual Word Recognition
Authors: Michal Lavidor, Vincent Walsh
Venue: Journal of Cognitive Neuroscience (2003)

The split-fovea theory proposes that visual word recognition is mediated by the splitting of the foveal image, with letters to the left of fixation projected to the right hemisphere (RH) and letters to the right of fixation projected to the left hemisphere (LH). We applied repetitive transcranial magnetic stimulation (rTMS) over the left and right occipital cortex during a lexical decision task to investigate the extent to which word recognition processes could be accounted for according to the split-fovea theory. Unilateral rTMS significantly impaired lexical decision latencies to centrally presented words, supporting the suggestion that foveal representation of words is split between the cerebral hemispheres rather than bilateral. Behaviorally, we showed that words that have many orthographic neighbors sharing the same initial letters ("lead neighbors") facilitated lexical decision more than words with few lead neighbors. This effect did not apply to end neighbors (orthographic neighbors sharing the same final letters). Crucially, rTMS over the RH impaired lead-, but not end-neighborhood facilitation. The results support the split-fovea theory, where the RH has primacy in representing lead neighbors of a written word.
Image Denoising with Shrinkage and Redundant Representations
Authors: Michael Elad, Boaz Matalon, Michael Zibulevsky
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 2 (2006)

Shrinkage is a well known and appealing denoising technique. The use of shrinkage is known to be optimal for Gaussian white noise, provided that the sparsity on the signal's representation is enforced using a unitary transform. Still, shrinkage is also practiced successfully with nonunitary, and even redundant representations. In this paper we shed some light on this behavior. We show that simple shrinkage could be interpreted as the first iteration of an algorithm that solves the basis pursuit denoising (BPDN) problem. Thus, this work leads to a novel iterative shrinkage algorithm that can be considered as an effective pursuit method. We demonstrate this algorithm, both on synthetic data, and for the image denoising problem, where we learn the image prior parameters directly from the given image. The results in both cases are superior to several popular alternatives.
Clock-Gating in FPGAs: A Novel and Comparative Evaluation
Authors: Yan Zhang, Jussi Roivainen, Aarne Mammela
Venue: Proceedings of the 9th EUROMICRO Conference on Digital System Design (2006)

Clock-gating has been employed in low-power FPGA designs based on an emulated and compromised method. So far in literature the actual efficiency of savings in power consumption is not thoroughly studied for this method. In this paper we evaluated the clock-gating technique in FPGAs, based on a novel and comparative process. For a set of design cases, both the FPGA and ASIC clock-gating methods were implemented. Figures of power consumption were obtained using the corresponding FPGA/ASIC power estimation tools and devices. The results show that in FPGAs, the efficiency of savings in dynamic power consumption is about 50% to 80% of its ASIC counterparts. However, we also found that compared to ASICs, clock-gating for FPGAs in terms of the efficiency of savings in total average power consumption was only about 6% to 30% of its ASIC counterparts due to FPGA's large static power consumption.
Peer-to-Peer Secure and Private Community Based Multimedia Communications
Authors: Pantelis A. Frangoudis, George C. Polyzos
Venue: Proceedings of the Eighth IEEE International Symposium on Multimedia (2006)

We have designed and implemented P2PWNC, a fully distributed, open to all, autonomous WLAN roaming scheme that can be used in a community to provide various multimedia communication services. Here we discuss various security related issues and the support provided by P2PWNC for several aspects of communication and roaming privacy. We also report on aspects of its performance, focusing on the performance penalty of security-related operations. The core P2PWNC scheme assumes that community members are selfish and do not trust each other and uses a secure incentive technique to encourage their contribution. It protects the real-world identities of community providers and clients by relying only on disposable opaque identifiers and does not rely on any authority to resolve disputes or control membership. It could easily complement cellular networks for low-mobility users in metropolitan areas where some Wireless Community Networks provide wide coverage.
Virtual planning rooms (ViPR): a 3D visualisation environment for hierarchical information
Authors: Michael Broughton
Venue: Proceedings of the 7th Australasian User interface conference - Volume 50 (2006)

The Future Operations Centre Analysis Laboratory (FOCAL) at Australia's Defence Science and Technology Organisation (DSTO) is aimed at exploring new paradigms for situation awareness (SA) and command and control (C2) in military command centres, making use of new technologies developed for virtual reality and real-time 3D animation. Recent work includes the conceptual design and prototype development of the Virtual Planning Rooms (ViPR), an innovative visualisation environment that displays multi-media information on the walls of immersive virtual rooms. The operator is able to view and interact with relevant information within the octagonal rooms, and to explore different levels of abstraction or alternative data sets by navigating through doorways to adjoining rooms. Random accessibility throughout the environment is also possible via interaction with a 3D map representing a high level view of the data. Potential uses for ViPR include course-of-action visualisation, planning or display of other hierarchical data sets. This paper provides an overview of FOCAL, followed by a brief description of ViPR that includes its conceptual design and prototype development, together with future directions.
True But Not False Memories Produce a Sensory Signature in Human Lateralized Brain Potentials
Authors: Monica Fabiani, Michael A. Stadler, Peter M. Wessels
Venue: Journal of Cognitive Neuroscience (2000)

False memories (e.g., recognition of events that did not occur) are considered behaviorally and subjectively indistinguishable from true memories. We report that brain activity differs when true and false memories are retrieved. Strongly associated lists of words were presented to one or the other cerebral hemisphere at study. This led to lateralized brain activity for these words during a centrally presented recognition test, reflecting their lateralized encoding. This activity was absent for nonstudied but strongly associated words falsely recognized as studied items. These results indicate that studied words leave sensory signatures of study experiences that are absent for false memories. In addition, hemifield effects emerged, including a slower reaction time (RT) for false recognition of nonstudied words whose associated lists were presented to the left hemifield (i.e., right hemisphere). These false recognition responses were accompanied by frontal slow wave activity, which may reflect a differential ability of the two hemispheres with respect to semantic processing.
Cycling Through a Dangerous Network: A Simple Efficient Strategy for Black Hole Search
Authors: Stefan Dobrev, Paola Flocchini, Nicola Santoro
Venue: Proceedings of the 26th IEEE International Conference on Distributed Computing Systems (2006)

In this paper we consider a dangerous process located at a node of a network (called Black Hole ) and a team of mobile agents deployed to locate that node. The nature of the danger is such that when an agent enters the dangerous node, it is trapped there leaving no trace of its destruction. The goal is to deploy as few agents as possible and to locate the black hole in as few moves as possible. We present a simple algorithm that works on any topology (a-priori known by the agents). Our algorithm, based on the pre-computation of an open vertex cover by cycles of the network, uses the optimal number of agents (two); its cost (number of moves) depends on the choice of the cover and it is optimal for several classes of networks.
4GHz continuous-time bandpass delta-sigma modulator for directly high IF A/D conversion
Authors: A. A. Mariano, D. Dallet, Y. Deval, J-B. Begueret
Venue: Proceedings of the 19th annual symposium on Integrated circuits and systems design (2006)

We present in this article a fourth-order integrated LC bandpass Delta-Sigma modulator for direct conversion of high intermediate frequencies. It is designed in a 0.25 μm BiCMOS SiGe:C process from STMicroelectronics. The modulator is able to direct digitize a 1GHz IF signal in a 20MHz bandwidth. The continuous-time loop filter employs two integrated LC resonators with active Q?enhancement circuits. A multi-feedback architecture is used to achieve higher order noise-shaping, while maintaining the modulator stability. A multibit quantizer was implemented to reduce quantization noise and improve stability.
Towards intelligent string matching in query-by-humming systems
Authors: C. Parker
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

In the past 5-10 years, there have been several attempts at the creation of a musical database that can be queried acoustically. The main problem hindering such efforts so far has been scalability, with limits of the frequently used three-character representation for melodic contour becoming apparent even at relatively small database sizes. Extending the contour representation to 24 semi-tone resolutions would go a long way towards solving such problems, but applying current string matching methods to a 24 character alphabet would prove difficult at best, and human errors would be far more prevalent. Here we show that the vast majority of errors at this resolution, although more numerous, are quite predictable using current methods of probabilistic modeling. This is evidence which we hope opens the door to more intelligent forms of note matching.
From MOO to MEOW: domesticating technology for online communities
Authors: Patricia Schank, Jamie Fenton, Mark Schlager, Judi Fusco
Venue: Proceedings of the 1999 conference on Computer support for collaborative learning (1999)

TAPPED IN is an on-line teacher professional development (TPD) research testbed designed to meet the needs of a large and diverse community of education professionals. The MOO technology that supports the testbed has demonstrated sustainability, usability, desirability, and utility across a wide-rage of activities and users. However, we are quickly coming up against technology scaling and integration issues as our community grows and demands new collaborative capabilities emerging on the Internet. Informed by our experience with TAPPED IN and reviews of related work, we are developing a new online "community-ware" technology called MEOW (Multi-user Educational Online Workspace) which can scale to handle large virtual communities. Under development in Java and related frameworks, MEOW introduces the concepts of persons, places, and things in a way intended to bind together many existing and emerging Internet services (e.g., web, email, ftp, search, recommendation) that are useful to a virtual community. Our goal is for MEOW to become a flexible, powerful, yet inexpensive platform for all forms of educational research and practice on the Internet. We invite others to join TAPPED IN and help us design the social spaces and technology to address the implications of online communities.
Experimental performance evaluation of histogram approximation for simulation output analysis
Authors: E. Jack Chen, W. David Kelton
Venue: Proceedings of the 36th conference on Winter simulation (2004)

We summarize the results of an experimental performance evaluation of using an empirical histogram to approximate the steady-state distribution of the underlying stochastic process. We use a runs test to determine the required sample size for simulation output analysis and construct a histogram by computing sample quantiles at certain grid points. The algorithm dynamically increases the sample size so that histogram estimates are asymptotically unbiased. Characteristics of the steady-state distribution, such as the mean and variance, can then be estimated through the empirical histogram. The preliminary experimental results indicate that the natural estimators obtained based on the empirical distribution are fairly accurate.