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11.
The effect of pressure on transition displacement between trickle and pulsed regimes (TPR: trickle-pulsed transition) in catalytic trickle bed reactors (CTBR) is not properly predicted by existing theoretical models and empirical correlations. Based on high pressure TPR data available to date, a modified Charpentier diagram is proposed to quantify directly the effect of pressure in non-foaming systems. 相似文献
12.
The influence of chloride-ion concentration on the pitting behaviour of steel in saturated Ca(OH)2 solution was studied using the D.C. polarization technique. Results seem to indicate a threshold chloride level for the on-set of severe pitting around 3000 ppm, the pitting potential Ep exhibits dramatic drop and large hysteresis loops develop. The results provide insight into the pitting performance of steel in concrete and highlight the poor repassivation of this metal/environment system. 相似文献
13.
Lentils, rice and their blend (Koshary) were cooked by traditional Egyptian methods. Cooking resulted in slight changes in the total nitrogen, as well as in the non-protein nitrogen (NPN), ether extract and crude fibre of the three products, compared with raw grains. In contrast, significant decreases were found in the mineral elements, indicating losses through leaching, on washing and cooking. The mineral composition of lentils' cooking liquor confirmed this. 相似文献
14.
Mohammed Nurul Afsar Hua Chi 《Journal of Infrared, Millimeter and Terahertz Waves》1994,15(7):1161-1179
The room temperature application of sapphire as window material at higher frequencies is not feasible since its absorption coefficient increases almost linearly with increasing frequency in the millimeter wavelength region. At cryogenic temperature the absorption coefficient value decreases only by a few factors (factor of 2 to 3) in the 90 – 200 GHz region. The earlier reported temperature squared dependence (decrease) in the absorption coefficient or the loss tangent value is totally absent in our broad band continuous wave data we are reporting here (at 6.5 K, 35K, 77K and 300K) and one we reported at conferences earlier. Our results are verified by another technique. We utilize our precision millimeter wave dispersive Fourier transform spectroscopic techniques at room temperature and at cryogenic temperatures The extra high resistivity single crystal compensated silicon is no doubt the lowest loss material available at room temperature in the entire millimeter wavelength region At higher millimeter wave frequencies an extra high resistivity silicon window or an window made with extra high resistivity silicon coated with diamond film would certainly make a better candidate in the future. A single free standing synthetic diamond window seems to have higher absorption coefficient values at millimeter wavelength region at this time although it is claimed that it possesses good mechanical strength and higher thermal conductivity characteristics. It certainly does not rule out the use of diamond film on a single crystal high resistivity silicon to improve its mechanical strength and thermal conductivity 相似文献
15.
Alireza Montazeri Behzad Akbari Mohammed Ghanbari 《Peer-to-Peer Networking and Applications》2012,5(3):257-278
P2P video streaming networks are found as a scalable solution and an alternative for traditional client–server based video
streaming over the Internet. One of the significant issues affecting the success of any P2P streaming network is cooperation
between peers. Practical observations have proved the prevalence of free riders in P2P networks that degrade their performance.
To solve this problem, using incentive mechanisms, which encourage peers to contribute more in the network, is necessary.
In this paper, we designed and proposed a distributed and scalable incentive mechanism for mesh based P2P video streaming
networks. In the proposed approach the contribution of the peers is measured and maintained in a distributed fashion. Furthermore,
we proposed an incentive sending side scheduler in which peers are served based on their contribution in the network. Our
simulation evaluations show the efficiency of the proposed approach in improving the overall perceived video quality by the
non-free rider nodes and consequently in the whole network. 相似文献
16.
Mohammed Hawa Jamal S. Rahhal Dia I. Abu-Al-Nadi 《Peer-to-Peer Networking and Applications》2012,5(3):279-291
Peer-to-Peer (P2P) traffic has increased rapidly over the past few years, with file sharing providing the main drive behind
such traffic. In this work we perform a measurement study of the content shared over the popular BitTorrent P2P file sharing
network. We mathematically model the file size distributions of shared files after categorizing them into Audio, Video, Archive
and CD image classes. For each of these categories we look into the most popular shared file formats and investigate their
file size statistics. This provides an important milestone to building a realistic simulation framework for P2P systems, and
for future analytical modeling of P2P networks. 相似文献
17.
Fahd A. Alhaidari Saleh A. Al-Dossary Ilyas A. Salih Abdlrhman M. Salem Ahmed S. Bokir Mahmoud O. Fares Mohammed I. Ahmed Mohammed S. Ahmed 《计算机系统科学与工程》2021,36(1):57-67
Geologists interpret seismic data to understand subsurface properties and subsequently to locate underground hydrocarbon resources. Channels are among the most important geological features interpreters analyze to locate petroleum reservoirs. However, manual channel picking is both time consuming and tedious. Moreover, similar to any other process dependent on human intervention, manual channel picking is error prone and inconsistent. To address these issues, automatic channel detection is both necessary and important for efficient and accurate seismic interpretation. Modern systems make use of real-time image processing techniques for different tasks. Automatic channel detection is a combination of different mathematical methods in digital image processing that can identify streaks within the images called channels that are important to the oil companies. In this paper, we propose an innovative automatic channel detection algorithm based on machine learning techniques. The new algorithm can identify channels in seismic data/images fully automatically and tremendously increases the efficiency and accuracy of the interpretation process. The algorithm uses deep neural network to train the classifier with both the channel and non-channel patches. We provide a field data example to demonstrate the performance of the new algorithm. The training phase gave a maximum accuracy of 84.6% for the classifier and it performed even better in the testing phase, giving a maximum accuracy of 90%. 相似文献
18.
The bivariate distributions are useful in simultaneous modeling of two random variables. These distributions provide a way to model models. The bivariate families of distributions are not much widely explored and in this article a new family of bivariate distributions is proposed. The new family will extend the univariate transmuted family of distributions and will be helpful in modeling complex joint phenomenon. Statistical properties of the new family of distributions are explored which include marginal and conditional distributions, conditional moments, product and ratio moments, bivariate reliability and bivariate hazard rate functions. The maximum likelihood estimation (MLE) for parameters of the family is also carried out. The proposed bivariate family of distributions is studied for the Weibull baseline distributions giving rise to bivariate transmuted Weibull (BTW) distribution. The new bivariate transmuted Weibull distribution is explored in detail. Statistical properties of the new BTW distribution are studied which include the marginal and conditional distributions, product, ratio and conditional momenst. The hazard rate function of the BTW distribution is obtained. Parameter estimation of the BTW distribution is also done. Finally, real data application of the BTW distribution is given. It is observed that the proposed BTW distribution is a suitable fit for the data used. 相似文献
19.
Abbass Mohammed Y. Kwon Ki-Chul Kim Nam Abdelwahab Safey A. El-Samie Fathi E. Abd Khalaf Ashraf A. M. 《Artificial Intelligence Review》2021,54(5):3349-3360
Artificial Intelligence Review - Visual object tracking has become one of the most active research topics in computer vision, and it has been applied in several commercial... 相似文献
20.
Obiora Valentine Saha Chitta Bazi Ammar Al Guha Koushik 《Microsystem Technologies》2021,27(8):3161-3169
Microsystem Technologies - This paper presents a critical analysis of the meta-heuristic techniques used in various researches on the optimisation of photovoltaic (PV) parameters, which involves... 相似文献