ppxscal/embedding_network huggingface dataset:
Overhead Analysis of a Dynamic Load Balancing Library for Cluster Computing
Authors: Ioana Banicescu, Ricolindo L. Carino, Jaderick P. Pabico, Mahadevan Balasubramaniam
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 1 - Volume 02 (2005)

This paper investigates the overhead of a dynamic load balancing library for large irregular data-parallel scientific applications on general-purpose clusters. The library is based on an integrated approach combining the advantages of novel dynamic loop scheduling strategies as data migration policies with the advances in resource management and task migration capabilities offered by a recently developed parallel runtime system. The paper focuses on the contribution of the runtime system software layer to the total overhead of the library. Experiments to compare the performance of two applications using the library, the Nbody simulations and the profiling of a quadrature routine, with the performance of the same applications using an MPI-only implementation of the dynamic scheduling techniques indicate only a slight decrease in performance due to the overhead of the runtime system software layer. The results validate the suitability of the runtime system as an implementation platform for dynamic load balancing schemes, and underscore the significance of using the integrated approach, as well as the benefits of using the library especially in cluster applications characterized by irregular and unpredictable behavior.
Some results on the minimal coverings of precomplete classes in partial k-valued logic functions
Authors: Ren-Ren Liu, Song-Qiao Chen, Jian-Er Chen, Shu Li
Venue: Journal of Computer Science and Technology (2004)

In completeness theories of multiple-valued logic, the characterization of Sheffer functions is an important issue. The solution can be reduced to determining the minimal coverings of precomplete classes. In this paper, some Full Symmetric Function Sets (m = 3) are proved to be components of the minimal covering of precomplete classes in Pk*.
Common knowledge and consistent simultaneous coordination
Authors: Gil Neiger, Mark R. Tuttle
Venue: Distributed Computing (1993)

There is a very close relationship between common knowledge and simultaneity in synchronous distributed systems. The analysis of several well-known problems in terms of common knowledge has led to round-optimal protocols for these problems, including Reliable Broadcast, Distributed Consensus, and the Distributed Firing Squad problem. These problems require that the correct processors coordinate their actions in some way but place no restrictions on the behaviour of the faulty processors. In systems with benign processor failures, however, it is reasonable to require that the actions of a faulty processor be consistent with those of the correct processors, assuming it performs any action at all. We consider problems requiring consistent, simultaneous coordination. We then analyze these problems in terms of common knowledge in several failure models. The analysis of these stronger problems requires a stronger definition of common knowledge, and we study the relationship between these two definitions. In many cases, the two definitions are actually equivalent, and simple modifications of previous solutions yield round-optimal solutions to these problems. When the definitions differ, however, we show that such problems cannot be solved, even in failure-free executions.
Security Design and Evaluation in a VoIP Secure Infrastracture: A Policy Based Approach
Authors: Valentina Casola, Massimiliano Rak, Antonino Mazzeo, Nicola Mazzoccca
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume I - Volume 01 (2005)

This paper aims at defining security levels of a Voice over IP infrastructure during its design phase. The proposed technique uses security policies to express the security statements that could be adopted, and the policy evaluation is based on security metrics to compare policies. The technique first step consists of policy structure definition; the proposed approach will be applied on the target VoIP infrastructure. In the second step of the technique, the policy will be used to define reference levels against which a security designer can evaluate his design choice or compare the adopted security solution with existing ones.
Design of an embedded cost model for mobile queries
Authors: Mohammad Hussein, Franck Morvan, Abdelkader Hameurlain
Venue: Proceedings of the 1st French-speaking conference on Mobility and ubiquity computing (2004)

In the context of heterogeneous and distributed data sources in large scale, the traditional optimizers generate execution plans can be sub-optimal because: the estimations are inaccurate, the unavailability of data and the execution environment is unstable. To deal with the sub-optimality of an execution plan, an approach consists to execute each relational operator of an execution plan by a mobile agent. This one can migrate from a site to the other one to comply. The information stored in the site, where the agent is situated, can be insufficient to calculate the site of migration of the agent. In this paper, we propose integrating into the mobile agent, executing an operator, a cost model. This last one allows the mobile agent to choose its site of migration the most appropriate.
Allocating Applications in Distributed Computing
Authors: Daniel A. Menasce
Venue: IEEE Internet Computing (2005)

Grid computing and virtualization can help distribute computing applications on the Internet, letting a collection of interconnected servers host a set of applications to balance the processing load and improveperformance. An important question is which applications to assign to which servers to meet the applications quality of service (QoS) goals, given the servers' bandwidth and capacity constraints.
Using Peer-to-Peer Communication to Improve the Performance of Distributed Computing on the Internet
Authors: Kasame Tritrakan, Veera Muangsin
Venue: Proceedings of the 19th International Conference on Advanced Information Networking and Applications - Volume 2 (2005)

This paper presents the design and evaluation of a distributed computing platform on the Internet that employs peer-to-peer communication for transferring data directly among participants without consuming schedulerýs bandwidth. The aim is to reduce network congestion at the scheduler by utilizing available peer-to-peer bandwidth. The peer-to-peer model is evaluated and compared to the client/server model in different system settings. The impacts of various factors, including the dynamic nature of a peer-to-peer system, on the performance and scalability are studied. The experimental results show that when peer-to-peer communication is applied, even partially, the bandwidth demands on the scheduler significantly reduced. This results in improved systemýs performance and scalability, and better support for data-intensive applications.
Spectral efficiency of distributed MIMO code division multiple access systems over multipath fading channels: Research Articles
Authors: Zhi Ni, Daoben Li
Venue: Wireless Communications Mobile Computing (2005)

Distributed multiple-input multiple-output (MIMO) system is a new architecture for next generation wireless communication systems with distributed multiple antennas. In this paper, an uplink model for multiuser distributed MIMO systems with wideband code-division multiple-access (CDMA) technology is presented. We focus on the case where there is no channel state information at the transmitter, but channel state information is assumed at the receiver. The spectral efficiency of the uplink system with single-user detectors at the base stations under multipath fading channels is investigated carefully. Two cases with different assumptions of interference knowledge are studied in detail. The spreading sequences of the CDMA systems are assumed to employ loosely synchronized (LS) spreading sequences and random spreading sequences respectively. LS spreading sequences exhibit a so-called interference free window (IFW), where both the auto-correlation and cross-correlation of the codes become zero. Therefore LS sequences have the promise of mitigating the effects of inter symbol interference (ISI) and multiple access interference (MAI) in multipath fading channels. It is shown by numerical results that the uplink spectral efficiency of the distributed MIMO-CDMA system using LS sequences can significantly outperform that of the system using random spreading sequences. Copyright &copy; 2005 John Wiley & Sons, Ltd.
Convexification and Concavification for a General Class of Global Optimization Problems
Authors: Z. Y. Wu, F. S. Bai, L. S. Zhang
Venue: Journal of Global Optimization (2005)

A kind of general convexification and concavification methods is proposed for solving some classes of global optimization problems with certain monotone properties. It is shown that these minimization problems can be transformed into equivalent concave minimization problem or reverse convex programming problem or canonical D.C. programming problem by using the proposed convexification and concavification schemes. The existing algorithms then can be used to find the global solutions of the transformed problems.
Performance evaluation of a random-walk-based algorithm for embedding dynamically evolving trees in hypercubic networks: Research Articles
Authors: Keqin Li
Venue: Concurrency and Computation: Practice Experience (2004)

In many tree-structured parallel computations, the size and structure of a tree that represents a parallel computation is unpredictable at compile-time; the tree evolves gradually during the course of the computation. When such a computation is performed on a static network, the dynamic tree embedding problem is to distribute the tree nodes to the processors of the network such that all the processors receive roughly the same amount of load and that communicating nodes are assigned to neighboring processors. Furthermore, when a new tree node is generated, it should be immediately assigned to a processor for execution without any information on the further evolving of the tree; and load distribution is performed by all processors in a totally distributed fashion.We study the problem of embedding dynamically evolving trees in hypercubic networks, including shuffle-exchange, de Bruijn, cube-connected cycles, wrapped butterfly, and hypercube networks. The performance of a random-walk-based randomized tree embedding algorithm is evaluated. Several random tree models are considered. We develop recurrence relations for analyzing the performance of embedding of complete-tree-based random trees and randomized complete trees, and linear systems of equations for reproduction trees. We present more efficient recurrence relations and linear systems of equations for symmetric networks. We also demonstrate extensive numerical data of the performance ratio and make a number of interesting observations of randomized tree embedding in the five hypercubic networks. Copyright &copy; 2004 John Wiley & Sons, Ltd.
Intranet Portal Model and Metrics: A Strategic Management Perspective
Authors: Grant A. Jacoby, Luqi
Venue: IT Professional (2005)

By linking metrics and conversion ratios to key business processes, the intranet efficiency and effectiveness model helps corporations design better software for intranet portals.
Emotions and heart rate while sitting on a chair
Authors: Jenni Anttonen, Veikko Surakka
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2005)

New methods for unobtrusive monitoring of computer users' emotion psychophysiology are very much needed in human-computer interaction research. The present aim was to study heart rate changes during emotionally provocative stimulation. Six-second long auditory, visual, and audiovisual emotionally negative, neutral, and positive stimuli were presented to 24 participants. Heart rate responses were measured with a regular office chair embedded with electromechanical film (the EMFi chair) and with traditional earlobe photoplethysmography (PPG). Ratings of the stimuli were also collected. The results showed that the two heart rate measurements were significantly correlated, r = 0.99. In line with other studies the results showed that, in general, heart rate decelerated in response to emotional stimulation and it decelerated the most in response to negative stimuli as compared with responses to positive and neutral stimuli. Especially, emotional stimulation caused significant changes in heart rate at the 6th second from the stimulus onset. We suggest that the EMFi chair could be used in human-computer interaction for unobtrusive measurement of the user's emotional reactions.
Livenotes: a system for cooperative and augmented note-taking in lectures
Authors: Matthew Kam, Jingtao Wang, Alastair Iles, Eric Tse, Jane Chiu, Daniel Glaser, Orna Tarshish, John Canny
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2005)

We describe Livenotes, a shared whiteboard system and educational practice that uses wireless communication and tablet computing to support real-time conversations within small groups of students during lectures, independent of class size. We present an interface design that enables group members to interact with one another by taking lecture notes cooperatively, as well as to augment student note-taking by providing instructor slides in the background to annotate over. Livenotes was designed to facilitate more efficient, stimulating modes of learning that other collaborative approaches do not. We report how the system impacts cooperative learning in an undergraduate class and how students interacted with background slides in the workspace. We conclude with directions for improving the system and learning practice.
MicroRouting: A Scalable and Robust Communication Paradigm for Sparse Ad Hoc Networks
Authors: Saumitra M. Das, Himabindu Pucha, Y. Charlie Hu
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 12 - Volume 13 (2005)

Mobile ad hoc networks (MANETs) are selforganizing networks that provide rapid network connectivity in infrastructureless environments. Most routing protocols designed for MANETs assume connected networks. Such a restriction directly limits the application domains of MANETs. In this paper, we study the problem of providing time-critical data delivery in sparse ad hoc networks where network partitions can last for long periods, without imposing any restrictions on the node mobility. Supporting real-time communication with unconstrainedmobility is important to many mission-critical applications such as battle-fields and search and rescuein large-scale disaster areas. In this paper, we propose microrouting networks consisting of tiny nodes similar to sensors but without transducers (called microrouters) as a substrate for time-critical data delivery in sparse MANETs. We describe the microrouting protocol for the resulting hybrid network which exploits the fact that microrouters are stationary, but are constrained by energy and memory. We demonstrate the viability of the microrouting network architecture via detailed simulation evaluation. Our results show that microrouting networks running the microrouting protocol efficiently extend the connectivity of sparse MANETs and provide high packet delivery ratios.
Configurable Security Protocols for Multi-party Data Analysis with Malicious Participants
Authors: Bradley Malin, Edoardo Airoldi, Samuel Edoho-Eket, Yiheng Li
Venue: Proceedings of the 21st International Conference on Data Engineering (2005)

Standard multi-party computation models assume semi-honest behavior, where the majority of participants implement protocols according to specification, an assumption not always plausible. In this paper we introduce a multi-party protocol for collaborative data analysis when participants are malicious and fail to follow specification. The protocol incorporates a semi-trusted third party, which analyzes encrypted data and provides honest responses that only intended recipients can successfully decrypt. The protocol incorporates data confidentiality by enabling participants to receive encrypted responses tailored to their own encrypted data submissions without revealing plaintext to other participants, including the third party. As opposed to previous models, trust need only be placed on a single participant with no data at stake. Additionally, the proposed protocol is configurable in a way that security features are controlled by independent subprotocols. Various combinations of subprotocols allow for a flexible security system, appropriate for a number of distributed data applications, such as secure list comparison.
Re-engineering software architecture of home service robots: a case study
Authors: Moonzoo Kim, Jaejoon Lee, Kyo Chul Kang, Youngjin Hong, Seokwon Bang
Venue: Proceedings of the 27th international conference on Software engineering (2005)

With the advances of robotics, computer science, and other related areas, home service robots attract much attention from both academia and industry. Home service robots present interesting technical challenges to the community in that they have a wide range of potential applications, such as home security, patient caring, cleaning, etc., and that the services provided by the robots in each application area are being defined as markets are formed and, therefore, they change constantly.Without architectural considerations to address these challenges, robot manufacturers often focus on developing technical components (e.g., vision recognizer, speech processor, and actuator) and then attempt to develop service robots by integrating these components. When prototypes are developed for a new application, or when services are added, modified, or removed from existing robots, unexpected, undesirable, and often dangerous side-effects, which are known as feature interaction problem, happen frequently. Reengineering of such robots can make a serious impact in delivery time and development cost.In this paper, we present our experience of re-engineering a prototype of a home service robot developed by Samsung Advanced Institute of Technology. First, we designed a modular and hierarchical software architecture that makes interaction among the components visible. With the visibility of interactions, we could assign functional responsibilities to each component clearly. Then, we re-engineered existing codes to conform to the new architecture using a reactive language Esterel. As a result, we could detect and solve feature interaction problems and alleviate the dificulty of adding or updating components.
Towards a more realistic comparative analysis of multicomputer networks: Research Articles
Authors: H. Sarbazi-Azad, M. Ould-Khaoua, L. M. Mackenzie
Venue: Concurrency and Computation: Practice Experience (2004)

Several studies have examined the relative performance merits of the torus and hypercube taking into account the channel bandwidth constraints imposed by implementation technology. While the torus has been shown to outperform the hypercube under the constant wiring density constraint, the opposite conclusion has been reached when the constant pin-out constraint is considered. However, these studies have assumed a pure uniform traffic pattern and deterministic routing. The &lsquo;uniform traffic&rsquo; assumption is not always justifiable in practice as there are many real-world parallel applications that exhibit non-uniform traffic patterns, which can create unbalanced traffic such as hotspots in the network. This paper re-examines the performance merits of the torus and hypercube in the presence of hotspot traffic. The comparative analysis is based on fully adaptive routing as this has been gaining popularity in recent practical multicomputers. Moreover, it uses a new cost model that takes into account the implementation cost of the network and its routers. The results reveal that for moderate and large system sizes, lower dimensional k-ary n-cubes (e.g. 2D torus) always outperform their higher dimensional counterparts even under the pin-out constraint. Copyright &copy; 2004 John Wiley & Sons, Ltd.
Node Localization Using Mobile Robots in Delay-Tolerant Sensor Networks
Authors: Pubudu N. Pathirana Nirupama Bulusu, Andrey V. Savkin, Sanjay Jha
Venue: IEEE Transactions on Mobile Computing (2005)

We present a novel scheme for node localization in a Delay-Tolerant Sensor Network (DTN). In a DTN, sensor devices are often organized in network clusters that may be mutually disconnected. Some mobile robots may be used to collect data from the network clusters. The key idea in our scheme is to use this robot to perform location estimation for the sensor nodes it passes based on the signal strength of the radio messages received from them. Thus, we eliminate the processing constraints of static sensor nodes and the need for static reference beacons. Our mathematical contribution is the use of a Robust Extended Kalman Filter (REKF)-based state estimator to solve the localization. Compared to the standard extended Kalman filter, REKF is computationally efficient and also more robust. Finally, we have implemented our localization scheme on a hybrid sensor network test bed and show that it can achieve node localization accuracy within 1m in a large indoor setting.
Performing tasks on synchronous restartable message-passing processors
Authors: Bogdan S. Chlebus, Roberto De Prisco, Alex A. Shvartsman
Venue: Distributed Computing (2001)

This work considers the problem of performing t tasks in a distributed system of p fault-prone processors. This problem, called DO-ALL herein, was introduced by Dwork, Halpern and Waarts. The solutions presented here are for the model of computation that abstracts a synchronous message-passing distributed system with processor stop-failures and restarts. We present two new algorithms based on a new aggressive coordination paradigm by which multiple coordinators may be active as the result of failures. The first algorithm is tolerant of f < p stop-failures and does not allow restarts. Its available processor steps (work) complexity is S = O((t+ p logp/log log p) ċ log f) and its message complexity is M = O(t + plogp/ log logp +fp). Unlike prior solutions, our algorithm uses redundant broadcasts when encountering failures and, for p = t and large f, it achieves better work complexity. This algorithm is used as the basis for another algorithm that tolerates stop-failures and restarts. This new algorithm is the first solution for the DO-ALL problem that efficiently deals with processor restarts. Its available processor steps is S = O((t + plogp + f. min{log p, logf}), and its message complexity is M = O(t + plogp + fp), where f is the total number of failures.