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1.
Thi Minh-Thuyen Radwan Amr Huynh Thong Hwang Won-Joo 《Wireless Personal Communications》2019,109(4):2289-2303
Wireless Personal Communications - In the formulating of power control for wireless networks, the radio channel is commonly formulated using static models of optimization or game theory. In these... 相似文献
2.
F. A. Kandil B. F. Dyson 《Fatigue & Fracture of Engineering Materials & Structures》1993,16(5):509-527
Abstract— A quantitative model has been proposed which predicts the extent of lifetime scatter in low-cycle fatigue due to the influence of bending caused by load misalignment. The main components of the model are the mechanism of bending, the type of extensometer used to control strain and the fatigue characteristics of the material being assessed. Three mechanisms of bending have been studied and it is argued that the most damaging one is a consequence of a lateral offset in the centre-lines of the load-train with respect to either a machine's frame or ram. Scatter in lifetime is a maximum when strain is controlled by a single extensometer (which is generally the case) and when fatigue behaviour is dictated by crack initiation at the largest surface defect. Two types of scatter have been examined, (i) repeatability scatter due to testing practice within a single laboratory, and (ii) reproducibility scatter between laboratories. An example of the magnitude of reproducibility scatter due to bending has been given by using an equation based on the universal slopes method due to Manson. 相似文献
3.
Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors. 相似文献
4.
F. A. Kandil B. F. Dyson 《Fatigue & Fracture of Engineering Materials & Structures》1993,16(5):529-537
Abstract— Models for predicting scatter bands due to bending have been applied to four alloys, namely AISI 316L, Nimonic 101, 9 Cr-1 Mo, and IN 718. The alloys were tested extensively by 26 laboratories in an international round robin exercise sponsored by the Community Bureau of Reference (BCR) of the EC. After initially selecting data for analysis on the basis of their confirmed conformance to the ASTM bending criterion, it has been shown that in all four materials a major fraction of the data scatter could be attributed to bending. Furthermore, at the lowest strain range the predicted bending component represents the highest proportion of the experimental interlaboratory scatter. Many laboratories did not report any measure of bending and so could not be used in the initial analysis. However, a further interesting deduction from the models is that the entire BCR data-set can be encompassed within a scatter band based upon a bending criterion that is twice the allowable ASTM limit. Differences in the extent of scatter between materials at a given total strain range can be attributed to the gradient of the logarithmic plot of total strain range as a function of lifetime. 相似文献
5.
Jan Haas Karen S. Frese Farbod Sedaghat-Hamedani Elham Kayvanpour Rewati Tappu Rouven Nietsch Oguz Firat Tugrul Michael Wisdom Carsten Dietrich Ali Amr Tanja Weis Torsten Niederdrnk Michael P. Murphy Thomas Krieg Marcus Drr Uwe Vlker Jens Fielitz Norbert Frey Stephan B. Felix Andreas Keller Hugo A. Katus Benjamin Meder 《International journal of molecular sciences》2021,22(4)
With more than 25 million people affected, heart failure (HF) is a global threat. As energy production pathways are known to play a pivotal role in HF, we sought here to identify key metabolic changes in ischemic- and non-ischemic HF by using a multi-OMICS approach. Serum metabolites and mRNAseq and epigenetic DNA methylation profiles were analyzed from blood and left ventricular heart biopsy specimens of the same individuals. In total we collected serum from n = 82 patients with Dilated Cardiomyopathy (DCM) and n = 51 controls in the screening stage. We identified several metabolites involved in glycolysis and citric acid cycle to be elevated up to 5.7-fold in DCM (p = 1.7 × 10−6). Interestingly, cardiac mRNA and epigenetic changes of genes encoding rate-limiting enzymes of these pathways could also be found and validated in our second stage of metabolite assessment in n = 52 DCM, n = 39 ischemic HF and n = 57 controls. In conclusion, we identified a new set of metabolomic biomarkers for HF. We were able to identify underlying biological cascades that potentially represent suitable intervention targets. 相似文献
6.
Amr Fouda Mohamed A. Awad Ahmed M. Eid Ebrahim Saied Mohammed G. Barghoth Mohammed F. Hamza Mohamed F. Awad Salah Abdelbary Saad El-Din Hassan 《International journal of molecular sciences》2021,22(10)
The discovery of eco-friendly, rapid, and cost-effective compounds to control diseases caused by microbes and insects are the main challenges. Herein, the magnesium oxide nanoparticles (MgO-NPs) are successfully fabricated by harnessing the metabolites secreted by Penicillium chrysogenum. The fabricated MgO-NPs were characterized using UV-Vis, XRD, TEM, DLS, EDX, FT-IR, and XPS analyses. Data showed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with sizes of 7–40 nm at a maximum wavelength of 250 nm. The EDX analysis confirms the presence of Mg and O ions as the main components with weight percentages of 13.62% and 7.76%, respectively. The activity of MgO-NPs as an antimicrobial agent was investigated against pathogens Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans, and exhibited zone of inhibitions of 12.0 ± 0.0, 12.7 ± 0.9, 23.3 ± 0.8, 17.7 ± 1.6, and 14.7 ± 0.6 mm respectively, at 200 µg mL−1. The activity is decreased by decreasing the MgO-NPs concentration. The biogenic MgO-NPs exhibit high efficacy against different larvae instar and pupa of Anopheles stephensi, with LC50 values of 12.5–15.5 ppm for I–IV larvae instar and 16.5 ppm for the pupa. Additionally, 5 mg/cm2 of MgO-NPs showed the highest protection percentages against adults of Anopheles stephensi, with values of 100% for 150 min and 67.6% ± 1.4% for 210 min. 相似文献
7.
Amr Almaddah Sadi Vural Yasushi Mae Kenichi Ohara Tatsuo Arai 《Machine Vision and Applications》2014,25(4):845-857
As part of the face recognition task in a robust security system, we propose a novel approach for the illumination recovery of faces with cast shadows and specularities. Given a single 2D face image, we relight the face object by extracting the nine spherical harmonic bases and the face spherical illumination coefficients by using the face spherical spaces properties. First, an illumination training database is generated by computing the properties of the spherical spaces out of face albedo and normal values estimated from 2D training images. The training database is then discriminately divided into two directions in terms of the illumination quality and light direction of each image. Based on the generated multi-level illumination discriminative training space, we analyze the target face pixels and compare them with the appropriate training subspace using pre-generated tiles. When designing the framework, practical real-time processing speed and small image size were considered. In contrast to other approaches, our technique requires neither 3D face models nor restricted illumination conditions for the training process. Furthermore, the proposed approach uses one single face image to estimate the face albedo and face spherical spaces. In this work, we also provide the results of a series of experiments performed on publicly available databases to show the significant improvements in the face recognition rates. 相似文献
8.
Gelatin is a natural macromolecular protein. It contains a wide variety of amino acids in its polymer structure, and it is colorless to yellowish, water‐soluble, and tasteless. It is used as a dispersing agent, sizing medium, and coating for photographic films and in pharmaceutical formulations. In this study, biodegradable mulching, based on waste gelatin from pharmaceutical gelatin scraps (derived from pharmaceutical soft gelatin capsule production), was formulated via the casting of water solutions or suspensions into flexible and consistent films. Gelatin was blended with synthetic materials such as poly(vinyl alcohol) and other natural wastes such as sugar cane bagasse and sawdust. To all formulations, 2,4‐dichlorophenoxy acetic acid (2,4‐D) was added as a herbicide. The morphology and mechanical properties of the samples were investigated with scanning electron microscopy and tensile testing, respectively. The results showed that the produced films had controlled‐release properties. The effects of various additives and crosslinking on the films and the release of the herbicide 2,4‐D from the films were also investigated. The introduction of synthetic and natural additives reduced the release rate of 2,4‐D. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2313–2319, 2004 相似文献
9.
The solubility of CO2 in triethylene glycol monomethyl ether (TEGMME) has been measured at 40, 70 and 100°C at pressures up to 8.8 MPa. The results were correlated with the Peng-Robinson (1976) equation of state. The interaction parameters and Henry's constants were derived. 相似文献
10.
We present two algorithms that are near optimal with respect to the number of inversions present in the input. One of the
algorithms is a variation of insertion sort, and the other is a variation of merge sort. The number of comparisons performed
by our algorithms, on an input sequence of length n that has I inversions, is at most . Moreover, both algorithms have implementations that run in time . All previously published algorithms require at least comparisons for some c > 1.
M. L. Fredman was supported in part by NSF grant CCR-9732689. 相似文献