ppxscal/embedding_network huggingface dataset:
Impact of retransmission mechanisms on the performance of SCTP and TCP
Authors: Rumana Alamgir, Mohammed Atiquzzaman, William Ivancic
Venue: Proceedings of the 4th WSEAS International Conference on Applied Mathematics and Computer Science (2005)

The Stream Control Transmission Protocol (SCTP) has been developed as a reliable transport layer protocol for carrying PSTN signalling messages over IP networks. However, its advanced congestion control and fault tolerant features make it a strong competitor to the widely used TCP protocol. In this paper, we investigate the performance of SCTP in an error-prone network, and compared it with that of TCP. We have found that the performance of SCTP is higher than that of TCP for a range of wireless error probabilities. We have shown that differences in the retransmission mechanisms of the two protocols leads to the better performance of SCTP.
Randomness-Efficient Sampling within NC1
Authors: Alexander D. Healy
Venue: Computational Complexity (2008)

We construct a randomness-efficient averaging sampler that is computable by uniform constant-depth circuits with parity gates (i.e., in uniform AC 0[]). Our sampler matches the parameters achieved by random walks on constant-degree expander graphs, allowing us to apply a variety expander-based techniques within NC 1. For example, we obtain the following results: Randomness-efficient error-reduction for uniform probabilistic NC 1, TC 0, AC 0[] and AC 0: Any function computable by uniform probabilistic circuits with error 1/3 using r random bits is computable by circuits of the same type with error δ using r + O(log(1/δ)) random bits. An optimal bitwise biased generator in AC 0[]: There exists a 1/2Ω(n)-biased generator G : {0, 1} O(n) -> {0, 1}2n for which poly(n)-size uniform AC 0[] circuits can compute G(s) i given (s, i) {0, 1} O(n) x¿ {0, 1} n . This resolves question raised by Gutfreund and Viola (Random 2004). uniform BP . AC 0 uniform AC 0/O(n). Our sampler is based on the zig-zag graph product of Reingold, Vadhan Wigderson (Annals of Math 2002) and as part of our analysis we givean elementary proof of a generalization of Gillman's Chernoff Bound for Expander Walks (SIAM Journal on Computing 1998).
QoS as Means of Providing WSNs Security
Authors: Tamara Pazynyuk, JianZhong Li, George S. Oreku, LiQiang Pan
Venue: Proceedings of the Seventh International Conference on Networking (2008)

Wireless sensor networks are increasingly being used in applications where QoS and low cost are the overriding considerations. Conventional schemes of using sensor nodes and incorporating these three phenomenons (reliability, availability and serviceability) to attain QoS can effectively improve not only the reliability of the overall WSNs but security as well. We discuss the reverse look of QoS and hence present mathematically the three significant quality factors that should be currently taken into account in developing wireless sensor networks application services and security. We also discussed specific characteristics and constraints of wireless sensor networks, QoS factors required when developing security applications for such networks. To evaluated possibility of establishing secure wireless sensor network through QoS we have used Hawk nodes to demonstrate how security can be archived through QoS experimentally. The flow models show how the QoS can be integrated to increase the security and applications running in WSNs.
A model for high school computer science education: the four key elements that make it!
Authors: Orit Hazzan, Judith Gal-Ezer, Lenore Blum
Venue: Proceedings of the 39th SIGCSE technical symposium on Computer science education (2008)

This paper presents a model program for high school computer science education. It is based on an analysis of the structure of the Israeli high school computer science curriculum considered to be one of the leading curricula worldwide. The model consists of four key elements as well as interconnections between these elements. It is proposed that such a model be considered and/or adapted when a country wishes to implement a nation-wide program for high school computer science education.
Social recommendations at work
Authors: Tom Crecelius, Mouna Kacimi, Sebastian Michel, Thomas Neumann, Josiane X. Parreira, Ralf Schenkel, Gerhard Weikum
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

Online communities have become popular for publishing and searching content, and also for connecting to other users. User-generated content includes, for example, personal blogs, bookmarks, and digital photos. Items can be annotated and rated by different users, and users can connect to others that are usually friends and/or share common interests. We demonstrate a social recommendation system that takes advantages of users connections and tagging behavior to compute recommendations of items in such communities. The advantages can be verified via comparison to a standard IR technique.
User-Friendly Interface for the Smartphone-based Self Management of Pulmonary Rehabilitation
Authors: Oleg Medvedev, Alison Marshall, Alexey Antonov
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 01 (2008)

A prototype system has been developed, based on a mobile Smartphone linked via Bluetooth to a range of monitoring devices (pulse oximeter, blood pressure monitor, ECG monitor), with a facility to integrate to clinical information systems, to enable individuals to self manage their own healthcare. The system has been developed to be used in specific chronic disease applications. The research study described outlines three specific applications of chronic disease self management - nutrition and exercise monitor for weight reduction; - pulse oximeter and exercise monitor for pulmonary rehabilitation: - blood pressure monitor for coronary heart disease patients. The objectives of the work are to design the system around the clinical application, based on existing health service protocols. The key principles in design are to make the system accessible to and usable by both the medical professional and a lay user. The pulmonary rehabilitation application is explored in more detail, to demonstrate progress towards this end.
Efficient mining of salinity and temperature association rules from ARGO data
Authors: Yo-Ping Huang, Li-Jen Kao, Frode-Eika Sandnes
Venue: Expert Systems with Applications: An International Journal (2008)

This paper presents an efficient technique for analyzing ARGO ocean data comprising time series of salinity/temperature measurements where informative salinity/temperature patterns are extracted. Most traditional mining techniques focus on finding associations among items within one transaction and are therefore unable to discover rich contextual patterns related to location and time. In order to show the associated salinity/temperature variations among different locations and time intervals, for example, ''if the salinity rose from 0.15psu to 0.25psu in the area that is in the east-northeast direction and is near Taiwan, then the temperature will rise from 0^oC to 1.2^oC in the area that is in the east-northeast direction and is far away from Taiwan next month'', a quantitative inter-transaction association rules mining algorithm is proposed. The FITI and the PrefixSpan algorithms are adopted to maximize the mining efficiency. The strategy is applied to ocean salinity measurements obtained from the waters surrounding Taiwan. These experimental evaluations show that the proposed algorithm achieves better performance than other inter-transaction association rule mining algorithms.
Simplified bluetooth scatternet formation using maximal independent sets
Authors: Nejib Zaguia, Yassine Daadaa, Ivan Stojmenovic
Venue: Integrated Computer-Aided Engineering (2008)

Bluetooth standard allows the creation of piconets, with one node serving as its master and up to seven nodes serving as slaves. A Bluetooth ad hoc network can also be formed by interconnecting several piconets into a scatternet. Given a set of Bluetooth nodes which are positioned so that their unit disk graph is connected, the Bluetooth scatternet formation (BSF) problem is to select piconets, and assign master and slave roles in each piconet, so that the obtained scatternet is connected, has some desirable properties and good performance with respect to some metrics. In this article we propose BlueMis, a new BSF protocol based on maximal independent sets. BlueMis is a two phase protocol, in which the first phase is discovery and the second phase, is scatternet formation. In the discovery process, two hop neighbors are discovered. The second phase of BlueMis uses two iterations. In the first iteration a piconet containing a maximal independent set is constructed for every device, while the second iteration attempts to simplify the scatternet structure and to delete piconets not essential for the connectivity. This novel protocol is an attempt to simplify the BlueMesh procedure. Simulation results show that the average number of iterations in BlueMesh ranges from 2.7 to 4.5, compared to only 2 for BlueMis. The reduced overhead is a major gain and it represents our primary contribution in this paper. BlueMis is implemented and compared with BlueMesh, in terms of various characteristics. Experiments show that BlueMesh performs slightly better, in terms of the number of piconets and the number of slaves per piconet.
An Analytical Performance Model for Multistage Interconnection Networks with Blocking
Authors: John Garofalakis, Eleftherios Stergiou
Venue: Proceedings of the Communication Networks and Services Research Conference (2008)

Multistage Interconnection Networks (MINs) allow efficient communication between network components and also among the components of parallel systems. This paper presents an approximate performance model for self routing multistage interconnection networks, applied for 2x2 switches which are subject to blocking situations when the packets compete for a full output port of a next stage switch. We apply our model to variable network size MINs and we study the performance under different traffic conditions. In our approximation the bulk of packets that arrive in each cycle to the MIN inputs, follow a Bernoulli distribution. We derive an approximate formula for the utilization of each queue and based on this, we approximate the blocking behavior (probabilities) and the steady-state distributions of populations for each queue of the MIN. This novel analytical model is validated by extensive simulations. Our analytical method gives more accurate results than previous existing analytical models and converges very fast.
Optimal Routing in Sensor Networks for In-home Health Monitoring with Multi-factor Considerations
Authors: Xiaoling Wu, Brian J. d'Auriol, Jinsung Cho, Sungyoung Lee
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

Recent technological advances in wireless sensor networking have opened up new opportunities in healthcare systems. Future medical systems are expected to benefit the most in such areas as in-home assistance, smart nursing homes, and clinical trial. However the network system including body sensor networks and environmental sensor networks are normally comprised of energy constrained nodes. Furthermore, communication interference between multi mode nodes in such a dynamic system is also a challenge. This limitation has led to the crucial need for energy and mobility aware protocols to produce an efficient network. In this paper, we propose an energy and mobility aware multipath routing scheme for sensor networks in a smart homecare application. The remaining battery capacity, distance to the gateway, mobility and queue size of candidate sensor nodes in the local communication range are taken into consideration for next hop relay node selection, and Analytical Hierarchy Process (AHP) is applied for decision making. Simulation results show that this scheme can extend the network lifetime and reduce the packet loss rate and link failure rate since the mobility and buffer capacity is considered.
MAISE: An Interconnect Simulation Engine for Timing and Noise Analysis
Authors: Frank Liu, Peter Feldmann
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

This paper describes MAISE, an embedded linear circuit simulator for use mainly within timing and noise analysis tools. MAISE achieves the fastest possible analysis performance over a wide range of circuit sizes and topologies by an adaptive architecture that allows applying the most efficient combination of model reduction algorithms and linear solvers for each class of circuits. The main pillar of adaptability in MAISE is a novel nodal-analysis formulation (PNA) which permits the use of symmetric, positive-definite Cholesky solvers for all circuittopologies. Moreover, frequently occurring special cases, e.g., inductor-resistor tree structures result in particular types of matrices that are solved by an even faster linear time algorithm. Model order reduction algorithms employed in MAISE exploit symmetry and positive-definiteness whenever available and use symmetric-Lanczos iteration and nonstandard inner-products for generating the Krylov subspace basis. The efficiency of the new simulator is supported by a wide range of industrial examples.
Integrating recommendation models for improved web page prediction accuracy
Authors: Faten Khalil, Jiuyong Li, Hua Wang
Venue: Proceedings of the thirty-first Australasian conference on Computer science - Volume 74 (2008)

Recent research initiatives have addressed the need for improved performance of Web page prediction accuracy that would profit many applications, e-business in particular. Different Web usage mining frameworks have been implemented for this purpose specifically Association rules, clustering, and Markov model. Each of these frameworks has its own strengths and weaknesses and it has been proved that using each of these frameworks individually does not provide a suitable solution that answers today's Web page prediction needs. This paper endeavors to provide an improved Web page prediction accuracy by using a novel approach that involves integrating clustering, association rules and Markov models according to some constraints. Experimental results prove that this integration provides better prediction accuracy than using each technique individually.
An efficient parallel algorithm for the minimal elimination ordering (MEO) of an arbitrary graph
Authors: E. Dahlhaus
Venue: Proceedings of the 30th Annual Symposium on Foundations of Computer Science (1989)

The first efficient parallel algorithm for computing minimal elimination ordering (MEO) of an arbitrary graph is designed. The algorithm works in O(log/sup 3/n) parallel time and O(nm) processors on a concurrent-read-concurrent-write parallel random-access machine (CRCW PRAM) for an n-vertex, m-edge graph and is optimal up to polylogarithmic factor with respect to the best sequential algorithm of D. Rose et. al. (SIAM J. Comput., vol.5, p.266-83, 1976). As an application, the first efficient parallel solution to the problem of minimal fill-in for arbitrary graphs is given. The method of solution involves the development of new techniques for solving the connected minimal set system problem and combining them with some new divide-and-conquer methods.
Throughput Fairness Round Robin Scheduler for Non-Continuous Flows
Authors: Lijie Sheng, Haoyu Wen, BaoBao Wang
Venue: Proceedings of the Fourth International Conference on Networking and Services (2008)

A queue scheduling algorithm TFRR (Throughput Fairness Round Robin) is proposed and studied. TFRR provides better long-term fairness in case of the existence of non-continuous packet flows. Merit and deficiency of the classical fair queue algorithm DRR are studied. The phenomenon that there always exist some non-continuous flows is disclosed. TFRR is constructed based on DRR. Firstly TFRR guarantee the basic bandwidth need of all flows just like DRR. Then the surplus bandwidth is distributed to the flows that have lost bandwidth in the early non-continuous periods, to provide better long-term fairness with complexity of O(1). The improvement of the long-term fairness of TFRR, compared with DRR, is proved by inference and simulation.
Realising emergent image preprocessing tasks in cellular-automaton-alike massively parallel hardware
Authors: Marcus Komann, Dietmar Fey
Venue: International Journal of Parallel, Emergent and Distributed Systems (2007)

In this paper, we present an emergent computing architecture scheme, denoted as marching pixels (MPs), which is well-suited for massively-parallel embedded systems based realising smart optical sensors. Smart in this context refers to sensors in which signal capturing and signal processing is combined either in one chip or in a compact 3D chip stack. MPs are life-like agents, which are crawling within a pixel field in such a chip in order to find centre points and other attributes of objects in binary images. MPs fulfill these tasks only by utilising local interaction and stigmertic communication. Principal ideas, the architecture and first results are described in this paper along with a comparison to both conventional and other unconventional computing approaches.
Applications for IT-Risk Management - Requirements and Practical Evaluation
Authors: Heinz Lothar Grob, Gereon Strauch, Christian Buddendick
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

Nowadays the importance of a dedicated information security management (ISM) is undisputedly. One essential task in realizing a company's ISM is to implement a compulsory operational risk management (ORM) aiming also at ensuring the compliance with certain standards. The risks addressed by ORM prevalently result from information systems. A promising approach is to focus on business processes to combine the technical system focused perspective of security management with the more centralized perspective of operational risk management. Within this paper first we will deliver an introduction an integrated IT risk management and its corresponding decisions. Afterwards we will derive requirements for application systems in order to supporting decisions in IT-Risk Management. For this purpose a catalogue of requirements will be developed. Based on this catalogue software systems for IT security management and operational risk management were examined with regard to their adequacy for decision support in IT-Risk Management.
Retinex method based on adaptive smoothing for illumination invariant face recognition
Authors: Young Kyung Park, Seok Lai Park, Joong Kyu Kim
Venue: Signal Processing (2008)

In this paper, we propose the Retinex method for illumination invariant face recognition developed on the basis of adaptive smoothing technology. By the well-known Retinex theory, illumination is generally estimated and normalized by smoothing the input image first and then dividing the estimate into the original input image. Therefore, performance mainly depends on how good the estimated illumination is. The proposed method estimates illumination by iteratively convolving the input image with a 3x3 smoothing mask weighted by a coefficient via combining two measures of the illumination discontinuity at each pixel. We address a couple of additional concepts, which are designed to be suitable especially for face images. One is the new conduction function for adaptive smoothing, and the other is the smoothing constraint for more accurate description of real environments. In this way, we can achieve an efficient illumination normalization in which face images with even strong shadows are normalized efficiently. The proposed method is evaluated based on Yale face database B, CMU PIE database and AR face database by applying PCA. The comparative results indicate that the proposed method present consistent and promising results even when images under harsh illumination conditions are used as a training set.
Exploiting semantic web services in achieving flexible application integration in the microelectronics field
Authors: S. Izza, L. Vincent, P. Burlat
Venue: Computers in Industry (2008)

Nowadays, semantic integration constitutes an important approach to deal with heterogeneity within large and dynamic enterprises. Currently, the existing solutions are mainly based on the use of some standards and also middlewares in order to overcome the integration problem. These solutions generally fail as they do not scale to large number of applications and also fail as they do not provide more flexibility and agility. Here, solutions based on semantic web services are promising and they are being actively researched. The paper outlines the potential role that these technologies can offer in solving some key challenges such as semantic mediation and interoperation. In particular, the paper proposes a flexible approach called ODSOI (Ontology-Driven Service-Oriented Integration) that combines both service-oriented architectures and ontologies and that aims to deal correctly with some application integration issues.
Formal Techniques for the Analysis of Wireless Networks
Authors: A. K. McIver, A. Fehnker
Venue: Proceedings of the Second International Symposium on Leveraging Applications of Formal Methods, Verification and Validation (2006)

Wireless networks consist of small (possibly) portable devices which combine battery-operated computing power and wireless communications. There are a number of technical challenges associated with their operation. These are addressed in part by emerging protocols which attempt to make trade-offs between the various network phenomena in order to optimise overall performance relative to an intended application. Central to the protocol design process is the availability of rigorous tools and techniques for quantifying any putative performance advantage gained by a particular protocol, and the degree to which its use degrades overall network functionality. The tools performing this important task today are simulators but the results from them are often not realistic as they have not been validated against empirical data. In this paper we explore the benefits of a formal approach to the analysis of wireless networks; in particular we investigate how a careful mix of model checking and proof may be used both to validate design decisions, and to provide a full profile of quantitative performance-style behaviours. Moreover the counter example facility of model checking can illustrate clearly the limitations of some standard protocols. We demonstrate the methods on flooding and communications protocols.
Effects of varying Smagorinsky constant on simulating post-flashover fires
Authors: Gao-Wan Zou, He-Ping Tan, Wan-Ki Chow, Ye Gao
Venue: International Journal of Computational Fluid Dynamics (2007)

Air flow post-flashover room fire is weakly compressible. In this paper, Navier-Stokes equations in an appropriate form will be applied to simulate such motion. Large eddy simulation (LES) is used with the Smagorinsky sub-grid scale model. A pool fire was described by the combustion model based on simple and fast chemical reaction. Three-dimensional simulations were carried out by using different values of Smagorinsky sub-grid scale constant. Predicted results on air temperatures and radiative heat fluxes were compared with the experimental values. Results illustrated that the value of the Smagorinsky constant would affect the simulations for strong buoyant plume. Value of the Smagorinsky constant from 0.20 to 0.21 appears to be reasonable in simulating flashover with a filter width of 0.1 m.