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排序方式: 共有406条查询结果,搜索用时 31 毫秒
61.
Khaleel Mershad Qutaibah M. Malluhi Mourad Ouzzani Mingjie Tang Michael Gribskov Walid G. Aref Deo Prakash 《Distributed and Parallel Databases》2018,36(1):121-151
Data curation activities in collaborative databases mandate that collaborators interact until they converge and agree on the content of their data. In a previous work, we presented a cloud-based collaborative database system that promotes and enables collaboration and data curation scenarios. Our system classifies different versions of a data item to either pending, approved, or rejected. The approval or rejection of a certain version is done by the database Principle Investigators (or PIs) based on its value. Our system also allows collaborators to view the status of each version and help PIs take decisions by providing feedback based on their experiments and/or opinions. Most importantly, our system provided mechanisms for history tracking of different versions to trace the modifications and approval/rejection done by both collaborators and PIs on different versions of a data item. We labeled our system as Update-Pending-Approval model (or UPA). In this paper, we describe a high level SQL query interface language for PIs and collaborators to interact with the UPA framework. We define a set of UPA keywords that are used as a part of the history tracking mechanism to select specific versions of a data item, and a set of UPA options that select specific versions based on possible future decisions of PIs. We implemented our query interface mechanism on top of Apache Phoenix, taking into consideration that the UPA system was implemented on top of Apache HBase. We test the performance of the UPA query language by executing several queries that contain different complexity levels and discuss their results. 相似文献
62.
Sassi Abdessamed Bachir Abdelmalik Bechkit Walid 《Wireless Personal Communications》2021,116(3):2169-2186
Wireless Personal Communications - The ability to predict the arrival and residence time of mobile users at a particular place is essential for the development of a wealth of new applications and... 相似文献
63.
Anatase nanocrystalline titania coatings were produced on cotton fabrics from alkoxide solutions using a low-temperature sol–gel process under ambient pressure. Titania coatings of the anatase form were obtained via a classical hydrolysis and condensation reaction of titanium isopropoxide that was followed by a boiling water treatment for 180 min. Spectroscopic and microscopic characterizations of the titania thin films showed that the anatase form is predominant throughout the film after the boiling water treatment and that the size of the grains is about 20 nm. The titania coating on fabrics is a promising process for use as an antibacterial photocatalyst in the textile industry. 相似文献
64.
Walid A. Daoud John H. Xin Xiaoming Tao 《Journal of the American Ceramic Society》2004,87(9):1782-1784
We successfully prepared transparent and durable superhydrophobic silica-coating films on cotton substrates at low temperatures. The coatings were produced via cohydrolysis and polycondensation of a hexadecyltrimethoxysilane (HDTMS), tetraethoxyorthosilcate (TEOS), and 3-glycidyloxypropyltrimethoxysilane (GPTMS) mixture. The hydrophobic properties of the nanocomposite coatings were determined using contact-angle and water-gain measurements. The water contact angle for the coated substrates was 141°, whereas, before coating, the contact angle was 0° because of the superhydrophilic nature of cotton. The nanocomposite coating has new applications in daily used materials, especially those with low heat resistance, such as textiles and plastics, and as an environmentally friendly water-repellent substitute for fluorine compounds. 相似文献
65.
66.
Walid Daniel Dib 《生活用纸》2017,(11):50-51
Enka Hijyen公司是土耳其一家新进入婴儿纸尿裤行业的生产商,其业务预计将在近期加速增长,目标是在未来几年能够满足本地和区域市场的需求。Enka Hijyen的母公司Imam Kayali控股集团成立于1928年。开始是一家出售汽车零件的小型父子商店,如今已实现指数式增长,扩大为拥有700多名员工的集团公司。ImamKayali控股集团在评估了不断变化的婴儿纸尿裤市场的复杂性和盈利空间后,于2016年第1季度开始涉足纸尿裤行业。 相似文献
67.
The influence of surface roughness on the efficiency of a cyclic potentiodynamic passivation (CPP) method employed to increase the general and pitting corrosion resistance of 316LVM stainless steel was investigated. The results show that a decrease in surface roughness of both the surface on which the passive film was formed naturally and by the CPP method, results in an increase in general corrosion resistance of the material, while for the CPP-modified surface, a notable increase in pitting corrosion resistance was also observed. It was further demonstrated that the CPP method is highly effective in increasing the general and pitting corrosion resistance of 316LVM, and that its efficiency does not depend on the surface roughness. 相似文献
68.
Triboelectric and Piezoelectric Effects in a Combined Tribo‐Piezoelectric Nanogenerator Based on an Interfacial ZnO Nanostructure
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In this contribution, combined triboelectric and piezoelectric generators (TPEG) with a sandwich structure of aluminum‐polydimethylsiloxane/polyvinylidene fluoride composite‐carbon (Al‐PPCF‐Carbon) are fabricated for the purpose of mechanical energy harvesting. Improved by the surface modification of PPCF with zinc oxide (ZnO) nanorods through a hydrothermal method, the TPEG generates an open‐circuit voltage (Voc) of ≈40 V, a short‐circuit current (Isc) of 0.28 μA with maximum power density of ≈70 mWm?2, and maximum conversion efficiency of 34.56%. Subsequently, in order to understand the transduction mechanism of the triboelectric and piezoelectric effects, analyses focusing on the potential composition ratio in the final output and the impact of ZnO interfacial nanostructure are carried out. The observed potential ratio between triboelectric and piezoelectric effects is 12.75:1 and the highest potential improvement by ZnO nanorods of 21.8 V is achieved by the TPEG fabricated with spacer. Finally, the relationships between the voltage, power density, conversion efficiency, and the external load resistances are also discussed. Overall, the fabricated TPEG is proved to be a simple and effective nanogenerator in mechanical energy conversion with enhanced output potential and conversion efficiency. 相似文献
69.
Walid Ibrahim 《Journal of Electronic Testing》2007,23(5):421-434
In today’s semiconductor industry, where time-to-profit is a critical factor to remain competitive, missing the tight market
window might have serious implications including the risk of product cancellation. This places severe pressure on every aspect
related to the design and the verification of semiconductor chips to get the design ready for manufacturing in the shortest
time possible. To avoid the need for costly corrective steps and silicon re-spins during post-silicon verification, thorough
pre-silicon verification is essential to catch any design fault and estimate the design overall reliability before the design
is manufactured. This paper presents a novel EDA tool that helps the verification team improve the verification process in
several ways. It can be used to generate useful statistics regarding the complexity and the coverage of the created test vectors.
Experimental results prove that the verification team can successfully use the proposed tool to set their target coverage
and intelligently select the set of test vectors that achieves that target using the minimum number of computing cycles.
相似文献
Walid IbrahimEmail: |
70.