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排序方式: 共有302条查询结果,搜索用时 15 毫秒
1.
Journal of Materials Science: Materials in Electronics - The huge applications of red-light-emitting materials paying the research attention to reduce the cost of production and raw materials.... 相似文献
2.
Abdelmoty M. Ahmed Reda Abo Alez Gamal Tharwat Muhammad Taha B. Belgacem Ahmad M. J. Al Moustafa 《成像科学杂志》2020,68(1):11-23
ABSTRACTArabic sign language (ArSL) is method of communication between deaf communities in Arab countries; therefore, the development of systemsthat can recognize the gestures provides a means for the Deaf to easily integrate into society. In this research we implemented a computational structurefor an intelligent interpreter that automatically recognizes the isolated dynamic gestures. The proposed system recognizes and translates gesturesperformed with one or both hands. It comprises five subsystems, building dataset, video processing, feature extraction, mapping between ArSL and Arabictext, and text generation. To apply the system, 100-signs of ArSL was used, which was applied on 1500 video files. It's were divided into five classes:alphabet, numbers, "prepositions, pronouns and question words", Arabic life expressions, and "nouns and verbs". The evaluation indicated that thesystem automatically recognizes and translates isolated dynamic ArSL gestures by highly accurate manner. The results showed that the system accuracy is 95.8%. 相似文献
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4.
Moustafa M. S. Sanad Mohamed M. Rashad El‐Sayed A. Abdel‐Aal Mohamed F. El‐Shahat Kevin W. Powers 《International Journal of Applied Ceramic Technology》2014,11(5):864-871
Molybdenum‐doped cordierite ceramics have been fabricated through facile combined techniques, coprecipitation followed by solid state. XRD results revealed that α‐cordierite phase is predominated with increasing Mo6+ ion content. The density measurements showed that the bulk density reduced to the minimum value of 0.61 g/cm3, which corresponds to the maximum porosity of about 76.8% at 5% Mo6+ ion. The dielectric permittivity (ε) of pure cordierite is decreased with increasing Mo6+ ion content. The minimum dielectric loss of Mo‐doped cordierite at 1 MHz was equal 0.008 with 10% Mo6+, while at 1 GHz was equal 0.03 with 5% Mo6+. 相似文献
5.
Abouhaswa A. S. Badr M. H. Nasr M. H. Elkholy M. M. El-Deen L. M. S. Turky Gamal M. Moustafa M. EL-Hamalawy A. A. 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(2):486-498
Journal of Inorganic and Organometallic Polymers and Materials - Cd1 ? xMnxFe2O4 (x?=?0, 0.25, 0.5, 0.75, 1) spinel ferrite nanoparticle samples were synthesized... 相似文献
6.
研究铁对粉末冶金法制备铝基复合材料微观组织、力学性能及磁学性能的影响。利用机械混合制备含0,5%,10%和15%Fe(质量分数)的铝基复合材料。Al-Fe混合粉末经压制后在真空炉中600°C烧结1 h。XRD结果表明:在含有5%和10%Fe的试样中只有Fe和Al的衍射峰,而含有15%Fe的试样中则存在Al和Al13Fe4的衍射峰。实验结果表明:随着Fe含量的增加,材料的致密度和导热性变差。复合材料中的Fe可以提高其强度和硬度。材料的强化机制包括基体的晶粒细化,Fe颗粒的均匀分布以及Al13Fe4金属间化合物的形成。含有5%Fe试样的磁化强度为0.3816×10-3A·m2/g,对于含有10%Fe的试样,其磁化强度增加至0.6597×10-3A·m2/g,而对于含有15%Fe试样,其磁化强度降低至0.0702×10-3A·m2/g。这是由于在高铁试样中形成了反磁性的Al13Fe4金属间化合物导致磁化强度降低。 相似文献
7.
Khaled Moustafa 《Scientometrics》2016,108(3):1649-1650
8.
H. A. Essawy A. B. Moustafa M. E. Abd El-Aziz A. I. Hussein 《Polymer-Plastics Technology and Engineering》2016,55(11):1124-1130
Solid particles can stabilize emulsions instead of conventional surfactants. Emulsion polymerization of styrene, as an example of polymerizable oil, was processed in the present work after ultrasonication of styrene in water in the presence of silica nanoparticles as stabilizer. Field emission scanning electron microscopy, equipped with energy-dispersive X-ray unit, and transmission electron microscopy confirmed the formation of polystyrene particles covered by a sheath of self-assembled silica. Addition of these hybrids in different loadings (2–14 wt%) to polypropylene and ethylene vinyl acetate copolymer could improve their tensile strength and hardness. The mechanical enrichment could be attributed to the action of the silica shell layer to delay the phase separation process encountered between the polystyrene from one side and polypropylene/ethylene vinyl acetate from other side, which translates into different extents of reinforcements. 相似文献
9.
MCNPX code has been used for modeling and simulation of a supercell of CANDU Fuel, the supercell consists of two fuel bundle and adjuster rod. The fuel bundle are burnt in normal operation conditions of CANDU reactors. Natural uranium fuel is used in the model. The multiplication factor of the bundle is calculated during fuel burnup. The concentration of both uranium and plutonium isotopes are analysed in the bundle. The worth of the adjuster rod is calculated. Comparison of multiplication factor and worth of the adjuster rod with the previous published references showed good agreement. 相似文献
10.
The explosive increase in data demand coupled with the rapid deployment of various wireless access technologies have led to the increase of number of multi-homed or multi-interface enabled devices. Fully exploiting these interfaces has motivated researchers to propose numerous solutions that aggregate their available bandwidths to increase overall throughput and satisfy the end-user’s growing data demand. These solutions, however, do not utilize their interfaces to the maximum without network support, and more importantly, have faced a steep deployment barrier. In this paper, we propose an optimal deployable bandwidth aggregation system (DBAS) for multi-interface enabled devices. We present the DBAS architecture that does not introduce any intermediate hardware, modify current operating systems, modify socket implementations, nor require changes to current applications or legacy servers. The DBAS architecture is designed to automatically estimate the characteristics of applications and dynamically schedule various connections and/or packets to different interfaces. We also formulate our optimal scheduler as a mixed integer programming problem yielding an efficient solution. We evaluate DBAS via implementation on the Windows OS and further verify our results with simulations on NS2. Our evaluation shows that, with current Internet characteristics, DBAS reaches the throughput upper bound with no modifications to legacy servers. It also highlights the significant enhancements in the response time introduced by DBAS, which directly enhances the user experience. 相似文献