ppxscal/embedding_network huggingface dataset:
RAMS: a RDMA-enabled I/O cache architecture for clustered network servers
Authors: Peng Gu, Jun Wang
Venue: Proceedings of the international workshop on Storage network architecture and parallel I/Os (2004)

Previous studies show that intra-cluster communication easily becomes a major performance bottleneck for a wide range of small write-sharing workloads especially read-only workloads in modern clustered network servers. A Remote Direct Memory Access (RDMA) technique has been recommended by many researchers to address the problem but how to well utilize RDMA is still in its infancy. This paper proposed a novel solution to boost intra-cluster communication performance by creatively developing a RDMA-enabled collaborative I/O cache Architecture called RAMS, which aims to smartly cache the most recently used RDMA-based intra-cluster data transfer processes for future reuse. RAMS makes two major contributions to facilitate the RDMA deployment: 1) design a novel RDMA-based user-level buffer cache architecture to cache both intra-cluster transferred data and data references; 2) develop three propagated update protocols to attack a RDMA read failure problem. Comprehensive experimental results show that three proposed new update protocols of RAMS can slash the RDMA read failure rate by 75%, and indirectly boost the system throughput by more than 50%, compared with a baseline system using Remote Procedure Call (RPC).
Contribution of the Primate Superior Colliculus to Inhibition of Return
Authors: Michael C. Dorris, Raymond M. Klein, Stefan Everling, Douglas P. Munoz
Venue: Journal of Cognitive Neuroscience (2002)

The phenomenon of inhibition of return (IOR) has generated considerable interest in cognitive neuroscience because of its putative functional role in visual search, that of placing inhibitory tags on objects that have been recently inspected so as to direct further search to novel items. Many behavioral parameters of this phenomenon have been clearly delineated, and based on indirect but converging evidence, the widely held consensus is that the midbrain superior colliculus (SC) is involved in the generation of IOR. We had previously trained monkeys on a saccadic IOR task and showed that they displayed IOR in a manner similar to that observed in humans. Here we recorded the activity of single neurons in the superficial and intermediate layers of the SC while the monkeys performed this IOR task. We found that when the target was presented at a previously cued location, the stimulus-related response was attenuated and the magnitude of this response was correlated with subsequent saccadic reaction times. Surprisingly, this observed attenuation of activity during IOR was not caused by active inhibition of these neurons because (a) they were, in fact, more active following the presentation of the cue in their response field, and (b) when we repeated the same experiment while using the saccadic response time induced by electrical micro-stimulation of the SC to judge the level of excitability of the SC circuitry during the IOR task, we found faster saccades were elicited from the cued location. Our findings demonstrate that the primate SC participates in the expression of IOR; however, the SC is not the site of the inhibition. Instead, the reduced activity in the SC reflects a signal reduction that has taken place upstream.
Reactive Speed Control in Temperature-Constrained Real-Time Systems
Authors: Shengquan Wang, Riccardo Bettati
Venue: Proceedings of the 18th Euromicro Conference on Real-Time Systems (2006)

In this paper, we study temperature-constrained realtime systems, where real-time guarantees must be met without exceeding safe temperature levels within the processor. We give a short review on temperature issues in processors and describe how speed control can be used to trade-off task delays against processor temperature. In this paper, we describe how traditional worst-case execution scenarios do not apply in temperature-constrained situations. As example, we adopt a simple reactive speed control technique. We show how this simple reactive scheme can improve the processor utilization compared with any constantspeed scheme.
A Declarative Approach for Specifying User-Centric Communication
Authors: Peter J. Clarke, Vagelis Hristidis, Yingbo Wang, Nagarajan Prabakar, Yi Deng
Venue: Proceedings of the International Symposium on Collaborative Technologies and Systems (2006)

The rapidly growing, reliable network infrastructure available today is enabling several classes of communication and collaborative applications. Already, a wide range of communication applications, tools and services (e.g., IP telephony, instant messaging, digital video conferencing, and multimedia collaboration), and many domain- or industry-specific communication applications (e.g., telemedicine, disaster management, and defense) have been developed and deployed. However, these communication applications have been conceived, designed and developed vertically and separately with little or no connection to each other. In addition, there has been little or no attention paid to how the end-user specifies his/her communication needs when using these applications. We propose a new paradigm to define user-centric communications, which is based on a simple and declarative Communication Modeling Language (CML) and a network abstraction middleware, which we call Communication Virtual Machine (CVM). To clarify this paradigm we draw a parallelism to the transformation that has taken place in the data management domain over the last two decades. In this paper we focus on CML and present two concrete and equivalent variants, an XML-based and a graphical. We argue that the proposed CML can facilitate the specification of a wide range of user-centric communication scenarios in several domains.
Modulation of Amygdalar Activity by the Conscious Regulation of Negative Emotion
Authors: Stacey M. Schaefer, Daren C. Jackson, Richard J. Davidson, Geoffrey K. Aguirre, Daniel Y. Kimberg, Sharon L. Thompson-schill
Venue: Journal of Cognitive Neuroscience (2002)

Lesion and neuroimaging studies suggest the amygdala is important in the perception and production of negative emotion; however, the effects of emotion regulation on the amygdalar response to negative stimuli remain unknown. Using event-related fMRI, we tested the hypothesis that voluntary modulation of negative emotion is associated with changes in neural activity within the amygdala. Negative and neutral pictures were presented with instructions to either "maintain" the emotional response or "passively view" the picture without regulating the emotion. Each picture presentation was followed by a delay, after which subjects indicated how they currently felt via a response keypad. Consistent with previous reports, greater signal change was observed in the amygdala during the presentation of negative compared to neutral pictures. No significant effect of instruction was found during the picture presentation component of the trial. However, a prolonged increase in signal change was observed in the amygdala when subjects maintained the negative emotional response during the delay following negative picture offset. This increase in amygdalar signal due to the active maintenance of negative emotion was significantly correlated with subjects' self-reported dispositional levels of negative affect. These results suggest that consciously evoked cognitive mechanisms that alter the emotional response of the subject operate, at least in part, by altering the degree of neural activity within the amygdala.
Designing a Ubiquitous Learning Workspace for Conducting Creative Thinking Exercise in Tertiary Design Education
Authors: Robert Kung-wong Lau
Venue: Proceedings of the Fourth IEEE International Workshop on Wireless, Mobile and Ubiquitous Technology in Education (2006)

This paper aims at exploring some major components of designing a ubiquitous learning workspace for conducting creative thinking exercise in tertiary design education. Discussed areas are including how (1) ICT can create surprise to students by unpredictable information; (2) to identify obstacles to creativity in designing ubiquitous workspace; (3) to understand the role of design lecturer in workspace; and (4) to use ICT in teaching and learning creative thinking exercise. This study is not going to give any solutions or models for designing ICT assisted learning platform, but to facilitate further discussions in adopting eLearning pedagogy in tertiary design education.
Online clustering of parallel data streams
Authors: Jürgen Beringer, Eyke Hüllermeier
Venue: Data Knowledge Engineering (2006)

In recent years, the management and processing of so-called data streams has become a topic of active research in several fields of computer science such as, e.g., distributed systems, database systems, and data mining. A data stream can roughly be thought of as a transient, continuously increasing sequence of time-stamped data. In this paper, we consider the problem of clustering parallel streams of real-valued data, that is to say, continuously evolving time series. In other words, we are interested in grouping data streams the evolution over time of which is similar in a specific sense. In order to maintain an up-to-date clustering structure, it is necessary to analyze the incoming data in an online manner, tolerating not more than a constant time delay. For this purpose, we develop an efficient online version of the classical K-means clustering algorithm. Our method's efficiency is mainly due to a scalable online transformation of the original data which allows for a fast computation of approximate distances between streams.
Risk and information in the estimation of hidden Markov models
Authors: Vahid R. Ramezani, Steven I. Marcus, Michael Fu
Venue: Proceedings of the 36th conference on Winter simulation (2004)

In this paper, we consider the relationship between risk-sensitivity and information. Product estimators are introduced as a generalization of Maximum A Posteriori Probability (MAP) estimator for Hidden Markov Models. We study the relationship between the inclusion of higher order moments, the underlying dynamics and the availability of information. Asymptotic periodicity of these estimators and the relationship between risk and information is studied via simulation.
α-Well-posedness for Nash Equilibria and For Optimization Problems with Nash Equilibrium Constraints
Authors: M. Beatrice. Lignola, Jacqueline Morgan
Venue: Journal of Global Optimization (2006)

We present the concepts of ¿-well-posedness for parametric noncooperative games and for optimization problems with constraints defined by parametric Nash equilibria. We investigate some classes of functions that ensure these types of well-posedness and the connections with ¿-well-posedness for variational inequalities and optimization problems with variational inequality constraints.
Adaptive agent negotiation via argumentation
Authors: Antonis Kakas, Pavlos Moraitis
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

In this paper, we study how argumentation can be used as a basis for negotiation between autonomous agents, where negotiation strategies of the different parties are represented as argumentation theories within their knowledge. We propose an argumentation based negotiation protocol in which offers by the negotiating parties are linked to different arguments that they can build according to their individual negotiation strategy. This protocol is able to take into account the different roles of agents and context of interaction, where the strength of the arguments supporting an offer can depend on these factors. The agents can adapt their negotiation strategies and offers, as their environment changes, in particular during the course of the negotiation as they exchange information. In addition, using abduction alongside with argumentation, agents can find negotiating conditions to support an argument for an offer, thus extending the negotiation object in order to help find an agreement. To illustrate further the advantages of the approach we also study how we can capture and extend negotiation strategies within another negotiation mechanism, in particular the well-known mechanism of bargaining with multiple parties. This exposes further the main advantages of modularity and flexibility of our argumentation based representation of negotiation strategies and the adaptability that this offers in a changing environment of negotiation.
A link weight assignment algorithm for traffic-engineered networks
Authors: E. Atteo, S. Avallone, S. P. Romano
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2006)

In this paper we address issues related to the definition of effective metrics for the application of load-balancing techniques inside providers' core networks. We will present an original approach to the problem of assigning appropriate weights to the network links. The main contribution of our work resides in having devised a solution relying on a cost function which depends on link utilization in a non-linear fashion. The paper discusses the rationale behind the choice of such a cost function and provides some experimental results and preliminary performance analysis.
On the duality of quantum filtering and optimal feedback control in quantum open linear dynamical systems
Authors: S. C. Edwards, V. P. Belavkin
Venue: Proceedings of the 2003 International Conference on Physics and Control - Volume 3 (2003)

The multi-dimensional quality open linear dynamical system with observation and feedback along a quantum linear transmission line is studied in discrete time. The linear least squares filtering and optimal control strategies are obtained as quantum analogies of the Kalman filter and Bellman dynamical programming. The duality of quantum filtering and optimal feedback control is observed for this particular case.
SMC process management dynamic model
Authors: Moiz Baig
Venue: Proceedings of the 36th conference on Winter simulation (2004)

The vision of the Space and Missile Center (SMC) of the Air Force is to achieve excellence in space system acquisitions by evolving as a process-centric operation. A team of experts from The Aerospace, SAIC, Sparta, and Northrup-Grumman are working under the SMC Directorate of System Acquisitions and the SMC Chief Engineer's Office to help develop the concept of operation, strategic plans and the infrastructure required to implement managed processes. The dynamic model example presented in this simulation case study attempts to provide a quantitative perspective of the process management CONOPS and paradigm change by taking processes through their life cycle. In the near future, the model will be populated with all SMC processes. The model uses Extend v6 with operations research module as platform. The author of the model and the demonstration movie is a member of the SMC process team and a senior principal investigator at Sparta Inc. 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
Defining and implementing domains with multiple types using mesodata modelling techniques
Authors: Sally Rice, John F. Roddick, Denise de Vries
Venue: Proceedings of the 3rd Asia-Pacific conference on Conceptual modelling - Volume 53 (2006)

The integration of data from different sources often leads to the adoption of schemata that entail a loss of information in respect of one or more of the data sets being combined. The coercion of data to conform to the type of the unified attribute is one of the major reasons for this information loss. We argue that for maximal information retention it would be useful to be able to define attributes over domains capable of accommodating multiple types, that is, domains that potentially allow an attribute to take its values from more than one base type.Mesodata is a concept that provides an intermediate conceptual layer between the definition of a relational structure and that of attribute definition to aid the specification of complex domain structures within the database. Mesodata modelling techniques involve the use of data types and operations for common data structures defined in the mesodata layer to facilitate accurate modelling of complex data domains, so that any commonality between similar domains used for different purposes can be exploited.This paper shows how the mesodata concept can be extended to facilitate the creation of domains defined over multiple base types, and also allow the same set of base values to be used for domains with different semantics. Using an example domain containing values representing three different types of incomplete knowledge about the data item (coarse granularity, vague terms, or intervals) we show how operations and data structures for types already existing within the mesodata can simplify the task of developing a new intelligent domain.
Advanced 3D signal processing for Virtual Team User Environments
Authors: O. Schreer, N. Atzpadin, S. Askar, P. Kauff
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

In this paper we present an advanced 3D signal processing for an extended architecture of 'Virtual Team User Environments (VIRTUE)' - a proposed concept on immersive 3D videoconferencing. Due to certain reasons the current VIRTUE architecture is restricted to a connection between three single user terminals. To overcome these shortcomings, a flexible multi-user concept is currently under investigation. One key challenge of such a multi-user concept is a robust 3D video processing including tracking, segmentation and depth analysis, which can be applied to a couple of participants sitting in front of the extended VIRTUE terminal. Against this background this paper presents a joint segmentation and disparity estimation approach which allows an accurate and robust 3D analysis providing the required input for an arbitrary synthesis of virtual views at the remote stations.
Multiplexing two information sources over fading channels: a cross-layer design perspective
Authors: Zhiyu Yang, Lang Tong
Venue: Signal Processing (2006)

We consider the transmission over an unknown frequency-selective channel of two independent sources with different application-layer characteristics: one source (such as voice) has a low information rate with a strict delay constraint; the other (such as data) has a high rate but without any delay constraints. We propose a system structure that jointly considers the different decoding requirements of the application layer and the unknown fading nature of the physical channel. In the proposed communication system, pilot symbols are not present and the low-rate information is decoded noncoherently first. The decoded low-rate codewords are then used for channel estimation to facilitate coherent decoding of the high-rate source. For a fixed detection error probability of the low-rate source, we derive achievable rate expressions for the high-rate source. We demonstrate a convergence behavior of the achievable rate of the high-rate source as the decision error probability of the low-rate source goes to zero. Numerical results show that the achievable rate of the high-rate source converges to that achievable by a training-based scheme at moderate decision error levels.
Shadows in the Brain
Authors: Umberto Castiello, Dean Lusher, Carol Burton, Peter Disler
Venue: Journal of Cognitive Neuroscience (2003)

The aims of the present study were to investigate whether the processing of an object shadow occurs implicitly, that is without conscious awareness, and where physically within the human brain shadows are processed. Here we present neurological evidence, obtained from studies of brain-injured patients with visual neglect, that shadows are implicitly processed and that this processing may take place within the temporal lobe. Neglect patients with lesions that do not involve the right temporal lobe were still able to process shadows to optimize object shape perception. In contrast, shadow processing was not found to be as efficient in neglect patients with lesions that involve the right temporal lobe.
A characterization of cocircuit graphs of uniform oriented matroids
Authors: Juan José Montellano-Ballesteros, Ricardo Strausz
Venue: Journal of Combinatorial Theory Series B (2006)

The cocircuit graph of an oriented matroid is the 1-skeleton of the cellular decomposition induced by the Topological Representation Theorem due to Folkman and Lawrence (1978) [J. Folkman, J. Lawrence, Oriented matroids, J. Combin. Theory Ser. B 25 (1978) 199-236]. In this paper we exhibit a characterization of such graphs (for the uniform case) via their natural embedding into Qnk-the 1-skeleton of the n-cube's k-skeleton's dual complex. The main theorem reads, basically, as follows: A graph G is the cocircuit graph of a d-dimensional uniform oriented matroid on n elements if and only if its order is 2(n d+2), and it can be embedded antipodally and "metrically" into Qn n-d-2.
Network-adaptive video streaming using multiple description coding and path diversity
Authors: Joohee Kim, R. M. Mersereau, Y. Altunbasak
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

This paper presents a TCP-friendly rate allocation algorithm for multiple description coding combined with path diversity. A 3-D SPIHT-based multiple description coding is used to generate two independent substreams and each substream is protected with an FEC-based unequal error protection algorithm. In the proposed video streaming framework, two senders simultaneously stream complementary substreams to the receiver over different paths. The proposed rate allocation algorithm coordinates distributed video streaming from multiple senders to a single receiver to minimize the overall distortion. Simulation results show that the proposed algorithm increases tolerance to packet loss due to network congestion and achieves higher visual quality compared to non-adaptive methods.
Synthetic humans in emergency response drills
Authors: Daniel Massaguer, Vidhya Balasubramanian, Sharad Mehrotra, Nalini Venkatasubramanian
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

Being able to realistically simulate humans in emergency response activities is a key challenge for advancing the field of information technology for emergency response. Building good human models enables testing information technology solutions in any emergency response simulated scenario. This paper presents an agent behavior model for mimicking peoples's behavior on emergency response activities. The accompanying demo demonstrates a concrete model for evacuations integrated with an emergency drill simulation environment.