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

Remineralization ability of two hydraulic calcium-silicate based dental pulp capping materials : cell-independent model

This study aimed to evaluate remineralizing ability of two hydraulic calcium-silicate cements (Biodentine and TheraCal LC). Artificial carious lesions were introduced into the pulpal floors (1-1.5 mm) and axial walls of occlusal prepared cavity halves through pH cycling. Cycling was made through demineralizing solution (pH 3), for 8 hours and remineralizing solution (pH 7) for 16 hours. The total period of pH cycling was 14 days. Prepared cavities with the tested materials seated directly on the pulpal floor and in contact with the axial walls were stored in phosphate buffer solutions (PBS) (pH 7.2?7.4). The changes in the weight percentages (wt%) of calcium (Ca) and phosphorus (P) were detected using SEM and energy dispersive X-ray spectroscopy with reference to sound dentin after three intervals (one week, 3 and 6 months). Data were statistically analyzed using two-way ANOVA and Tukey?s post hoc test. Demineralized dentin, next to Biodentine, showed statistically higher intensities of Ca and P wt% after the three periods of incubation (p< 0.05). Surface mapping of both tested cements and their adjacent demineralized dentin showed increase in overall distribution of previous ions. SEM of subsurface layer under both materials showed filling of most intra-tubular areas with rod-like mineralized structure without significant difference. Biodentine has a higher ability to enrich the artificial carious dentin with significantly higher mineral contents available for remineralization. Both pulp-capping materials have significantly induced remineralization of demineralized dentin beneath them after total period of incubation

INHIBITION OF TUMOUR NECROSIS FACTOR (TNF) ACTIVITY BY A NEW ERGOSTANE STEROID FROM CLEOME DROSERIFOLIA

Objective: To isolate steroidal compound from Cleome droserifolia and explore its activity against tumour necrosis factor (TNF) using molecular docking studies.Methods: Extraction of the plant material was carried using two successive solvents and three compounds were isolated using column chromatography. The isolated compounds were identified using different spectroscopic data such as 1D, 2D nuclear magnetic resonance (NMR), ultraviolet-visible spectroscopy (UV-Visible), fourier transform infrared spectroscopy (FT-IR) and electrospray ionization mass spectroscopy (ESI-MS). Molecular docking was carried in order to investigate the activity of the ergostane derivative as tumour necrosis factor inhibitor.Results: Two steroidal compounds were isolated and identified as ergost-5,7,9,24 (28)-tetraen-3-one (1) and β-sitosterol glucoside (3) by means of spectroscopic measurement. 1-dodecanol (2) was also isolated. The ergostane derivative showed several binding sites with TNF-αConclusion: The new ergostane derivative isolated from the aerial parts of Cleome droserifolia is introduced to serve as a potential tumour necrosis factor inhibitor and may be used as a lead compound for the treatment of rheumatoid arthritis

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

Implications of publication ban orders in Egypt on press journalists’ work and news dissemination

The issue of publication ban orders in Egypt, more commonly known as “gag orders”, has risen to public attention in recent years in Egypt. This attention has reflected in many reports emerging with rich data on the frequency and significance of publication ban orders. This thesis takes advantage of this recent availability of data to broach this topic on which there has been limited past academic research, particularly in Egypt. Such orders have barred the media from covering lawsuits that were mostly of a high public-opinion value, usually involving high and mid-ranking officials of government, security or judicial personnel. This qualitative thesis explores how these orders unfold in reality, and to what degree they affect journalist activity and news dissemination in Egypt. The findings of this study reveal a number of issues of direct practical impact on journalists’ activity, including legal dilemmas, an information blackout following such an order, and an increased sense of a limited media sphere. With regards to news disseminations, trends discussing the role of rumors and digital media in spreading news about a banned topic have also been detected

Reinvestigation of the Reaction of Phenacy lMalononitrile with Hydrazines under Solvent Conditions

Phenacylmalononitrile 3 reacts with hydrazine hydrate in refluxing dioxan to afford the iminopyridazine derivative 6 and the pyrazolo[3,4-c]pyridazine derivative 7.Compound 3 reacts also with phenylhydrazine in refluxing ethanol to afford the iminopyridazine derivative 11 along with the phenylhydrazone derivative 12. Compound 12 could be cyclized into the pyrazolo[3,4-c]pyridazine derivative 13 upon reflux with sodium ethoxide

Real-time Anomaly Detection and Localization in Crowded Scenes

In this paper, we propose a method for real-time anomaly detection and localization in crowded scenes. Each video is defined as a set of non-overlapping cubic patches, and is described using two local and global descriptors. These descriptors capture the video properties from different aspects. By incorporating simple and cost-effective Gaussian classifiers, we can distinguish normal activities and anomalies in videos. The local and global features are based on structure similarity between adjacent patches and the features learned in an unsupervised way, using a sparse autoencoder. Experimental results show that our algorithm is comparable to a state-of-the-art procedure on UCSD ped2 and UMN benchmarks, but even more time-efficient. The experiments confirm that our system can reliably detect and localize anomalies as soon as they happen in a video

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 %