Performance modeling of fault-tolerant circuit-switched communication networks

Circuit switching (CS) has been suggested as an efficient switching method for supporting simultaneous communications (such as data, voice, and images) across parallel systems due to its ability to preserve both communication performance and fault-tolerant demands in such systems. In this paper we present an efficient scheme to capture the mean message latency in 2D torus with CS in the presence of faulty components. We have also conducted extensive simulation experiments, the results of which are used to validate the analytical mode

Software-based fault-tolerant routing algorithm in multidimensional networks

Massively parallel computing systems are being built with hundreds or thousands of components such as nodes, links, memories, and connectors. The failure of a component in such systems will not only reduce the computational power but also alter the network's topology. The software-based fault-tolerant routing algorithm is a popular routing to achieve fault-tolerance capability in networks. This algorithm is initially proposed only for two dimensional networks (Suh et al., 2000). Since, higher dimensional networks have been widely employed in many contemporary massively parallel systems; this paper proposes an approach to extend this routing scheme to these indispensable higher dimensional networks. Deadlock and livelock freedom and the performance of presented algorithm, have been investigated for networks with different dimensionality and various fault regions. Furthermore, performance results have been presented through simulation experiments

On quantifying fault patterns of the mesh interconnect networks

One of the key issues in the design of Multiprocessors System-on-Chip (MP-SoCs), multicomputers, and peerto- peer networks is the development of an efficient communication network to provide high throughput and low latency and its ability to survive beyond the failure of individual components. Generally, the faulty components may be coalesced into fault regions, which are classified into convex and concave shapes. In this paper, we propose a mathematical solution for counting the number of common fault patterns in a 2-D mesh interconnect network including both convex (|-shape, | |-shape, ý-shape) and concave (L-shape, Ushape, T-shape, +-shape, H-shape) regions. The results presented in this paper which have been validated through simulation experiments can play a key role when studying, particularly, the performance analysis of fault-tolerant routing algorithms and measure of a network fault-tolerance expressed as the probability of a disconnection

An Empirical Method for Estimating Global Solar Radiation over Egypt

Global solar radiation has been estimated on the basis of measurements of sunshine duration for different selected sites in Egypt; (Marsa-Matruh, Cairo, Aswan, Al-Kharga, Abu-Simble and Halaib-Shalatin). The regression coefficients (a) and (b) of Angstrom type correlation are calculated for the selected sites. The values of the regression coefficients are found to vary from 0.219–0.611 and 0.107–0.576, respectively. These values have been calculated by three different approaches. The estimated values of the global solar radiation are compared with the measured values. Although the (a) and (b) values differ from one site to another; the summation (a+b) is almost the same for the selected sites. The difference between the estimated and measured values of the global solar radiation at the various sites varies from 4 % to 12 %

Learning With Imbalanced Data in Smart Manufacturing: A Comparative Analysis

The Internet of Things (IoT) paradigm is revolutionising the world of manufacturing into what is known as Smart Manufacturing or Industry 4.0. The main pillar in smart manufacturing looks at harnessing IoT data and leveraging machine learning (ML) to automate the prediction of faults, thus cutting maintenance time and cost and improving the product quality. However, faults in real industries are overwhelmingly outweighed by instances of good performance (faultless samples); this bias is reflected in the data captured by IoT devices. Imbalanced data limits the success of ML in predicting faults, thus presents a significant hindrance in the progress of smart manufacturing. Although various techniques have been proposed to tackle this challenge in general, this work is the first to present a framework for evaluating the effectiveness of these remedies in the context of manufacturing. We present a comprehensive comparative analysis in which we apply our proposed framework to benchmark the performance of different combinations of algorithm components using a real-world manufacturing dataset. We draw key insights into the effectiveness of each component and inter-relatedness between the dataset, the application context, and the design of the ML algorithm

Food composition and feeding ecology of the Red Fox Vulpes vulpes (Linnaeus, 1758) in Egypt

Food composition of the Red Fox Vulpes vulpes populations in different habitats in Egypt is investigated based on the analysis of stomach contents. The analysis of 70 stomach contents demonstrates that the food of Red Fox is highly diverse and includes rodents, birds, reptiles,fishes, insects and other arthropods, fruits and other vegetable material. Certain individuals seem to also feed on carrion. Diet composition shows seasonal and geographical variations that are apparently associated with changes in the availability of different food items. The results clearlyshow that the Red Fox is an opportunistic omnivore, capable of adapting to a great variety of dietary compositions

Color Portion of Solar Radiation in the Partial Annular Solar Eclipse, October 3rd, 2005, at Helwan, Egypt

Measurements were made of various solar radiation components, global, direct and diffuse and their fractions during the partial annular solar eclipse on October 3rd, 2005 at Helwan, Egypt (Lat. 29.866◦ N and Long. 31.20◦ E), and an analysis has been made. The duration of the solar eclipse was 3 h 17 min, and the maximum magnitude of the eclipse in this region was 0.65. The optical depth of the direct component and the relative humidity decreased, while both the transparency and the air temperature increased towards the maximum eclipse. The general trends of the global components are decreasing optical depth and increasing transparency between the first contact and the last contact. The prevailing color during the eclipse duration was diffused infrared (77 % of the total diffuse radiation level)

An analytical model of pipelined circuit switching in hypercubes in the presence of hot spot traffic

Several recent studies have revealed that PCS can provide superior performance characteristics over wormhole switching under uniform traffic. Analytical model of PCS for common networks (e.g., hypercube) under uniform traffic pattern have recently been reported in the literature. In this paper we propose an analytical model of PCS in the hypercube network augmented with virtual channel in the presence of hot spot traffic. The model has a good agreement with simulation experiments

Synthesis and Molluscicidal Activity of Some Newly Substituted Chromene and Pyrano[2,3-c]pyrazole Derivatives

The arylidene derivatives 3a-f react with 1,3-cyclohexanedioneand dimedone 4a,b to afford the 4-(2- or 3-pyridyl) or 4-pipronyl-chromene derivatives 6a-l. The arylidene derivatives 3a-c react with the pyrazolone derivatives 7a,b to afford the pyrano[2,3-c]pyrazole derivatives 9af.The molluscicidal activity of the synthesized compounds towards Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni, was investigated and most of them showed weak to moderate activity.

Heterocyclic synthesis with ω-bromoacetophenone: Synthesis of some new pyrazole, pyridazine and furan derivatives

p-Bromophenacylnitrile derivatives 3a,b react with hydrazinederivatives under different conditions to afford the diaminopyrazoles 4a,b, the pyridazine-6-imines 5a,b,and 5-aminopyrazoles 11a,b. Refluxing of 5a in ethanol/hydrochloric acid mixture furnished its transformation into the pyridazine-6-one 6 while 5b under the same reaction conditions, underwent ring contraction expelling phenyl hydrazine to afford the furan derivative 7.Compound 7 could also be obtained from 3a upon refluxin ethanol catalyzed by triethylamine. Ethyl  phenacylcyanoacetate 3b reacts with hydrazine hydrate and phenylhydrazine to afford the 4-phenacylpyrazole derivatives11a,b respectively. Compound 3b afforded a mixture ofthe two furan derivatives 12 and 13 upon reflux in ethanolcatalyzed by triethylamine. Compound 3b also undergoesthe coupling reaction with the aromatic diazoniumsalts 14a-d to afford the pyrazole derivatives 16a-d presumablyvia the hydrazo derivatives 15a-d respectively