ppxscal/embedding_network huggingface dataset:
Jigsaw: solving the puzzle of enterprise 802.11 analysis
Authors: Yu-Chung Cheng, John Bellardo, Péter Benkö, Alex C. Snoeren, Geoffrey M. Voelker, Stefan Savage
Venue: ACM SIGCOMM Computer Communication Review (2006)

The combination of unlicensed spectrum, cheap wireless interfaces and the inherent convenience of untethered computing have made 802.11 based networks ubiquitous in the enterprise. Modern universities, corporate campuses and government offices routinely de-ploy scores of access points to blanket their sites with wireless Internet access. However, while the fine-grained behavior of the 802.11 protocol itself has been well studied, our understanding of how large 802.11 networks behave in their full empirical complex-ity is surprisingly limited. In this paper, we present a system called Jigsaw that uses multiple monitors to provide a single unified view of all physical, link, network and transport-layer activity on an 802.11 network. To drive this analysis, we have deployed an infrastructure of over 150 radio monitors that simultaneously capture all 802.11b and 802.11g activity in a large university building (1M+ cubic feet). We describe the challenges posed by both the scale and ambiguity inherent in such an architecture, and explain the algorithms and inference techniques we developed to address them. Finally, using a 24-hour distributed trace containing more than 1.5 billion events, we use Jigsaw's global cross-layer viewpoint to isolate performance artifacts, both explicit, such as management inefficiencies, and implicit, such as co-channel interference. We believe this is the first analysis combining this scale and level of detail for a production 802.11 network.
An efficient Bayes solution to AR signal modelling for short sequences
Authors: D. E. Johnston, P. M. Djuric
Venue: Proceedings of the Acoustics, Speech, and Signal Processing,1994. on IEEE International Conference - Volume 04 (1994)

A Bayesian approach to autoregressive (AR) signal modelling is proposed. In contrast to previous research, the exact posterior density of the model parameters is utilized and minimum mean square estimates (MMSE) are evaluated. To compute the estimates, a numerically efficient procedure is presented which can be viewed as an alternative to multidimensional optimization. Our approach can be used to investigate many signal characteristics such as the signal's spectrum, marginal densities for prediction or even model selection. Simulation results confirm our expectations and illustrate the improvement over the classic, maximum conditional likelihood (MCL) approach to AR signal modelling.
Interaction Comparison between Traditional Classroom and Cyber Classroom Using Transactional Distance
Authors: Nian-Shing Chen, Prof. Kinshuk, Sheng-Wen Hsieh, Stephen J. H. Yang
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

Blended learning (BL) is a hybrid of classroom learning and online learning that includes the conveniences of online courses without the complete loss of face-to-face (F2F) contact. Advancements in communication technologies now allow us to have synchronous distributed interactions that occur in realtime with close to the same levels of fidelity as in the F2F environment. Therefore, it is imperative that we understand how to create effective BL experiences that incorporate both traditional instruction and online instruction. This article uses mathematics model to formulate the transactional distance to compare the interaction distance of traditional centralized F2F and synchronous distributed F2F. Transactional distance is then used to know about the communication gap between learner and instructor, content, and other learners. Finally, the paper verifies the validity of the transactional distance calculated through the mathematical model with the help of survey that elicits students' perception towards those two environments.
An ultra low-power class-AB sinh integrator
Authors: Sandro A. P. Haddad, Wouter A. Serdijn
Venue: Proceedings of the 19th annual symposium on Integrated circuits and systems design (2006)

A new ultra low-power Class-AB Sinh integrator is proposed here. The translinear companding integrator is based on hyperbolic-sine transconductors and uses only one grounded capacitor to implement a Class-AB integrator, which saves considerable chip area. Furthermore, the proposed circuit presents excellent performance with respect to power efficiency. To validate the circuit principle, the integrator has been simulated in standard 35 μm CMOS technology and designed to operate from a 1.5-V (± 0.75V) supply voltage, with a current consumption of only 14nA. The THD is kept below 1%, with a modulation index as high as 20 and yields a 75-dB dynamic range at the 1-dB compression point.
Efficient heuristics for the simulation of population overflow in series and parallel queues
Authors: Victor F. Nicola, Tatiana S. Zaburnenko
Venue: Proceedings of the 1st international conference on Performance evaluation methodolgies and tools (2006)

In this paper we propose state-dependent importance sampling heuristics to estimate the probability of population overflow in Markovian networks of series and parallel queues. These heuristics capture state-dependence along the boundaries (when one or more queues are empty) which is critical for the asymptotic optimality of the change of measure. The approach does not require difficult (and often intractable) mathematical analysis or costly optimization involved in adaptive importance sampling methodologies. Experimental results on tandem and parallel networks with a moderate number of nodes yield asymptotically efficient estimates (often with bounded relative error) where no other state-independent importance sampling techniques are known to be efficient. Insight drawn from simulating basic networks in this paper promises the applicability of the proposed methodology to larger networks with more general topologies.
Effects of Syntactic Structure and Propositional Number on Patterns of Regional Cerebral Blood Flow
Authors: David Caplan, Nathaniel Alpert, Gloria Waters
Venue: Journal of Cognitive Neuroscience (1998)

Positron emission tomography (PET) was used to determine regional cerebral blood flow (rCBF) as a function of the syntactic form and propositional density of sentences. rCBF increased in the left pars opercularis, part of Broca's area, when subjects processed syntactically more complex sentences. There were no differences in rCBF in the perisylvian association cortex traditionally associated with language processing when subjects made plausibility judgments about sentences with two propositions as compared to sentences with one proposition, but rCBF increased in infero-posterior brain regions. These results suggest that there is a specialization of neural tissue in Broca's area for constructing aspects of the syntactic form of sentences to determine sentence meaning. They also suggest that this specialization is separate from the brain systems that are involved in utilizing the meaning of a sentence that has been understood to accomplish a task.
Approaches to multi-agent learning
Authors: Leslie Pack Kaelbling
Venue:  (2005)

Systems involving multiple autonomous entities are becoming more and more prominent. Sensor networks, teams of robotic vehicles, and software agents are just a few examples. In order to design these systems, we need methods that allow our agents to autonomously learn and adapt to the changing environments they find themselves in. This thesis explores ideas from game theory, online prediction, and reinforcement learning, tying them together to work on problems in multi-agent learning. We begin with the most basic framework for studying multi-agent learning: repeated matrix games. We quickly realize that there is no such thing as an opponent-independent, globally optimal learning algorithm. Some form of opponent assumptions must be necessary when designing multi-agent learning algorithms. We first show that we can exploit opponents that satisfy certain assumptions, and in a later chapter, we show how we can avoid being exploited ourselves. From this beginning, we branch out to study more complex sequential decision making problems in multi-agent systems, or stochastic games. We study environments in which there are large numbers of agents, and where environmental state may only be partially observable. In fully cooperative situations, where all the agents receive a single global reward signal for training, we devise a filtering method that allows each individual agent to learn using a personal training signal recovered from this global reward. For non-cooperative situations, we introduce the concept of hedged learning, a combination of regret-minimizing algorithms with learning techniques, which allows a more flexible and robust approach for behaving in competitive situations. We show various performance bounds that can be guaranteed with our hedged learning algorithm, thus preventing our agent from being exploited by its adversary. Finally, we apply some of these methods to problems involving routing and node movement in a mobilized ad-hoc networking domain. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Using simulation to select and evaluate potential Six Sigma projects
Authors: J. Bennett Foster
Venue: Proceedings of the 36th conference on Winter simulation (2004)

The DuPont Company has chosen the Six Sigma methodology as "the way we do business". Six Sigma's demand for quantifiable bottom line results is an excellent business discipline. At the same time, for many multi-stage production and supply chain operations, it is difficult to quantify the impact of a given project on overall earnings. Simulation is used in DuPont to help select projects which have high potential for increasing earnings. When the projects meet their immediate goals, simulation is used to quantify the contribution of that project to overall earnings improvement. A case study of a large multi-step chemical operation will be reviewed. 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
An optimization framework for joint sensor deployment, link scheduling and routing in underwater sensor networks
Authors: L. Badia, M. Mastrogiovanni, C. Petrioli, S. Stefanakos, M. Zorzi
Venue: Proceedings of the 1st ACM international workshop on Underwater networks (2006)

Underwater sensor networks are a very interesting case of wireless communication in extreme conditions. They exploit acoustic communication in sea water and are nowadays used in surveillance and monitoring applications. These networks present very challenging aspects, such as low data rates and large delays, as well as the special propagation characteristics of the underwater medium. We propose an integer-linear programming approach to jointly optimize routing, link-scheduling and node placement in such a scenario. Accounting for these special aspects of underwater wireless communications leads to re-thinking traditional approaches; this results in original solutions, which highlight novel directions for further research in this area.
Weakly Supervised Top-down Image Segmentation
Authors: Manuela Vasconcelos, Nuno Vasconcelos, Gustavo Carneiro
Venue: Proceedings of the 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition - Volume 1 (2006)

There has recently been significant interest in top-down image segmentation methods, which incorporate the recognition of visual concepts as an intermediate step of segmentation. This work addresses the problem of top-down segmentation with weak supervision. Under this framework, learning does not require a set of manually segmented examples for each concept of interest, but simply a weakly labeled training set. This is a training set where images are annotated with a set of keywords describing their contents, but visual concepts are not explicitly segmented and no correspondence is specified between keywords and image regions. We demonstrate, both analytically and empirically, that weakly supervised segmentation is feasible when certain conditions hold. We also propose a simple weakly supervised segmentation algorithm that extends state-of-theart bottom-up segmentation methods in the direction of perceptually meaningful segmentation1.
Minimizing the total weighted completion time on unrelated parallel machines with stochastic times
Authors: Jean-Paul M. Arnaout, Ghaith Rabadi
Venue: Proceedings of the 37th conference on Winter simulation (2005)

This paper addresses the problem of batch scheduling in an unrelated parallel machine environment with sequence dependent setup times and an objective of minimizing the weighted mean completion time. Identical jobs are batched together and are available at time zero. Processing time of each job of a batch is determined according to both the machine it will be assigned to and the batch group to which the job belongs. The jobs' processing times and setup times are stochastic for better depiction of the real world. This is a NP-hard problem and in this paper, a solution heuristic is developed and compared to existing ones using simulation. The results and analysis obtained from the computational experiments proved the superiority of the proposed algorithm PMWP over the other algorithms presented.
A Five-Step Method for Value-Based Planning and Monitoring of Systems Engineering Projects
Authors: Karl W. Wagner, Walter Durr
Venue: Proceedings of the 32nd EUROMICRO Conference on Software Engineering and Advanced Applications (2006)

Main activities of project management for the development of complex software-intensive systems are currently (a) to plan the project by selecting processes, methods and resources, and (b) to control the project by monitoring mainly cost and schedule, the so-called "earned values". Concentrating solely on these values bears the disadvantage that other important measures are not under observation. These often neglected measures comprise e.g. requirements clarity, which also contributes to the "system value" as it will be recognized by its stakeholders. Therefore the meaning of the term "value" has to be extended, taking also into account less- and non-monetary values and their monitoring has to start at early project phases (e.g. during requirements engineering). This paper describes a fivestep method which enriches the "earned value" concept with other important value aspects. This shall support Project Managers in their value-based planning and monitoring of systems engineering projects, thus increasing the value for the addressed stakeholders.
Integrating a Real-Time Captured Object into Mixed Reality
Authors: Hua Chen, Peter F. Elzer, Odej Kao
Venue: Proceedings of the 2006 International Conference on Cyberworlds (2006)

Web-based Mixed Reality (MR) that combines remote real objects with a virtual environment to form a realistic 3D MR space has received much interest in Cyberworlds. This paper introduces a novel method of integrating a live video object that is taken by multiple fixed cameras in a remote natural environment into a MR space. Using the captured live video frames, the view of the remote object corresponding to the user's current viewpoint in the MR space is generated in realtime based on the proposed fast view morphing algorithm, which ensures a natural image transition without reconstructing the 3D model of the object. During the user's free navigation in the MR space, the real-time generated view of the object is presented in that space, which results in a convincing impression that the remote object exists in the local realistic 3D MR space. Experimental results in both a desktop MR system and a CAVE-like MR system have demonstrated the validity of the proposed approach.
Negotiating about shared knowledge in a cooperative learning environment
Authors: Hans-Rüdiger Pfister, Martin Wessner, Torsten Holmer, Ralf Steinmetz
Venue: Proceedings of the 1999 conference on Computer support for collaborative learning (1999)

A goal of cooperative learning is the construction of shared knowledge. Shared knowledge represents the common understanding of a group of individuals with respect to the content domain; the active construction of shared knowledge enhances acquisition and retention. Two requirements have to be met during the construction process: First, shared knowledge should be represented explicitely; second, the participants' multiple perspectives need to be integrated. We focus on the second aspect, called knowledge negotiation, by which the learners' common understanding is construed. However, common understanding comes in degrees. We provide a theoretical perspective for the negotiation process and propose a quantification of shared knowledge, called the degree of agreement (degreement). Finally, we discuss how a learning environment for distributed learners can support the process of cooperative knowledge construction.
Virtual Backbone Construction in MANETs Using Adjustable Transmission Ranges
Authors: Jie Wu, Fai Dai
Venue: IEEE Transactions on Mobile Computing (2006)

Recently, the use of a virtual backbone in various applications in mobile ad hoc networks (MANETs) has become popular. These applications include topology management, point and area coverage, and routing protocol design. In a MANET, one challenging issue is to construct a virtual backbone in a distributed and localized way while balancing several conflicting objectives: small approximation ratio, fast convergence, and low computation cost. Many existing distributed and localized algorithms select a virtual backbone without resorting to global or geographical information. However, these algorithms incur a high computation cost in a dense network. In this paper, we propose a distributed solution based on reducing the density of the network using two mechanisms: clustering and adjustable transmission range. By using adjustable transmission range, we also achieve another objective, energy-efficient design, as a by-product. As an application, we show an efficient broadcast scheme where nodes (and only nodes) in a virtual backbone are used to forward the broadcast message. The virtual backbone is constructed using Wu and Li's marking process [37] and the proposed density reduction process. The application of the density reduction process to other localized algorithms is also discussed. The efficiency of our approach is confirmed through both analytical and simulation study.
Multi-dimensional Histograms with Tight Bounds for the Error
Authors: Linas Baltrunas, Arturas Mazeika, Michael Bohlen
Venue: Proceedings of the 10th International Database Engineering and Applications Symposium (2006)

Histograms are being used as non-parametric selectivity estimators for one-dimensional data. For highdimensional data it is common to either compute onedimensional histograms for each attribute or to compute a multi-dimensional equi-width histogram for a set of attributes. This either yields small low-quality or large highquality histograms. In this paper we introduce HIRED (HIgh-dimensional histograms with dimensionality REDuction): small highquality histograms for multi-dimensional data. HIRED histograms are adaptive, and they are based on the shape error and directional splits. The shape error permits a precise control of the estimation error of the histogram and, together with directional splits, yields a memory complexity that does not depend on the number of uniform attributes in the dataset. We provide extensive experimental results with synthetic and real world datasets. The experiments confirm that our method is as precise as state-of-the-art techniques and uses orders of magnitude less memory.
Distributed Construction and Maintenance of Bandwidth and Energy Efficient Bluetooth Scatternets
Authors: Metin Tekkalmaz Hasan Sozer Ibrahim Korpeoglu
Venue: IEEE Transactions on Parallel and Distributed Systems (2006)

Bluetooth networks can be constructed as piconets or scatternets depending on the number of nodes in the network. Although piconet construction is a well-defined process specified in Bluetooth standards, scatternet formation policies and algorithms are not well specified. Among many solution proposals for this problem, only a few of them focus on efficient usage of bandwidth in the resulting scatternets. In this paper, we propose a distributed algorithm for the scatternet formation problem that dynamically constructs and maintains a scatternet based on estimated traffic flow rates between nodes. The algorithm is adaptive to changes and maintains a constructed scatternet for bandwidth-efficiency when nodes come and go or when traffic flow rates change. Based on simulations, the paper also presents the improvements in bandwidth-efficiency and reduction in energy consumption provided by the proposed algorithm.
On a generalized k-out-of-n system and its reliability
Authors: Lirong Cui, Min Xie
Venue: International Journal of Systems Science (2005)

A consecutive-k-out-of-n system is a system with n components arranged either linearly or circularly, which fails if and only if at least k consecutive components fail. An (n,f,k) system further requires that the total number of failed components is less than f for the system to be working. Here we consider a more general system consisting of N modules with the ith module-composed of ni components in parallel: the system fails if find only if there exist at least f failed components or at least k consecutive failed modules. In this paper, some formulae for the reliability of such a generalized k-out-of-n system are derived for both the linear and the circular cases. The recursive formulae established here can be easily computed. Many existing results are also shown to be special cases of the results obtained in this paper. Furthermore, we investigate some component importance properties.
VIML: Toward Future Video Visualization and Interaction
Authors: Jesse Jin
Venue: Proceedings of the International Conference on Computer Graphics, Imaging and Visualisation (2006)

There is an increasing demand for the interaction between users and video streams. One example is the digital TV which will be popular in two years time. The advantage of digital TV is the interactivity it can do, not merely for a good picture. Users have a need to bring up theview in a special way. Another example is watching video in distance education scenario. There is a need to collect feedback from users and restructure the video presentation based on different responses. Video contains rich information. However, due to the organization of digital video streams, it is difficult to use hyperlinks similar to HTML links in Web pages. Video does not have the same hierarchical structure and organization as text.