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81.
ABSTRACTThis article examines equity concerns and inherent conflicts related to rural–urban water supply allocation and use, with focus on Metro Manila. Going beyond the much-discussed difficulty farmers experience from an allocation policy prioritizing urban water requirements, it shows that inequity in raw water allocation is linked to, and further exacerbated by, inequities in urban domestic water provision. Moreover, it highlights the need for broader equity reviews, using the concept of the rural–urban water equity nexus to draw attention to key equity considerations across space and scale that otherwise might remain invisible. 相似文献
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Aissaoui Ferhi Leila Sethom Kaouthar Choubani Fethi 《Wireless Personal Communications》2019,109(3):1769-1779
Wireless Personal Communications - With the attractive applications in e-Health, a booming interest is granted to wireless body area network (WBAN). Through WBAN, healthcare professionals can... 相似文献
85.
Leila Benarous Benamar Kadri Salim Bitam Abdelhamid Mellouk 《International Journal of Communication Systems》2020,33(10)
Privacy in Vehicular Ad Hoc Networks (VANET) is fundamental because the user's safety may be threatened by the identity and the real‐time spatiotemporal data exchanged on the network. This issue is commonly addressed by the use of certified temporal pseudonyms and their updating strategies to ensure the user's unlinkability and anonymity. IEEE 1609.2 Standard specified the process of certifying pseudonym along with certificates structure. However, the communication procedure between the certifying authority and the requesting vehicle was not defined. In this paper, a new privacy‐preserving solution for pseudonym on‐road on‐demand refilling is proposed where the vehicle anonymously authenticates itself to the regional authority subsidiary of the central trusted authority to request a new pseudonyms pool. The authentication method has two phases, the first one uses anonymous tickets, and the second one is a challenge‐based authentication. The anonymous tickets are certificates that do not include the identity of the user. Instead, it contains a reference number and the certifying authority signature. The challenge authentication is identity‐less to preserve the privacy, yet it is used to prevent the misuse of tickets and the impersonation of its owner. Our proposed scheme is analyzed by the use of Burrows, Abadi and Needham (BAN) logic to demonstrate its correctness. It is also specified and checked by using the Security Protocol ANimator (SPAN) and the Automated Validation of Internet Security Protocols and Applications (AVISPA) tools. The logical demonstration proved that this privacy‐preserving authentication is assured. The SPAN and AVISPA tools illustrated that it is resilient to security attacks. 相似文献
86.
Fabrication of Millimeter‐Long Carbon Tubular Nanostructures Using the Self‐Rolling Process Inherent in Elastic Protein Layers 下载免费PDF全文
Hyojin Ko Leila F. Deravi Sung‐Jin Park Jingon Jang Takhee Lee Cheong Kang Jin Seok Lee Kevin Kit Parker Kwanwoo Shin 《Advanced materials (Deerfield Beach, Fla.)》2017,29(31)
Millimeter‐long conducting fibers can be fabricated from carbon nanomaterials via a simple method involving the release of a prestrained protein layer. This study shows how a self‐rolling process initiated by polymerization of a micropatterned layer of fibronectin (FN) results in the production of carbon nanomaterial‐based microtubular fibers. The process begins with deposition of carbon nanotube (CNT) or graphene oxide (GO) particles on the FN layer. Before polymerization, particles are discrete and nonconducting, but after polymerization the carbon materials become entangled to form an interconnected conducting network clad by FN. Selective removal of FN using high‐temperature combustion yields freestanding CNT or reduced GO microtubular fibers. The properties of these fibers are characterized using atomic force microscopy and Raman spectroscopy. The data suggest that this method may provide a ready route to rapid design and fabrication of aligned biohybrid nanomaterials potentially useful for future electronic applications. 相似文献
87.
Scientometrics - This study provides a comprehensive analysis of patent family characteristics of triadic patents. We test specific features of triadic patent families to highlight common... 相似文献
88.
Polychlorinated biphenyls (PCBs) is one of the most persistent organic pollutants that exist in the atmosphere and can be concentrated in lithosphere and hydrosphere. Because of low biodegradability and lipophilicity, PCBs accumulate in fatty tissues and through oxidative stress could lead to cancers and central nervous system disorders. Currently, degradation of these synthetic pollutants is one of the environmental issues. The aim of this study is to provide a sensor for detection of PCB-153 (PCB-153). Nano boron nitride compounds (BnNm) are magic materials with high stability that can be used as a sensor for detection of chlorinated aromatic compounds. In this study, sensitivity of B80N80 as a form of single-walled boron nitride nanotubes (SW-B80N80 nanotube (8,8)) to PCB-153 has been investigated. The PCB-153 is closed to the SW-B80N80 nanotube and electron exchanges between them have been evaluated using density functional calculations by B3LYP/6–31G* method. The calculation of the electronic properties has shown that SW-B80N80 nanotube is very sensitive to the presence of PCB-153 molecules. The HOMO/LUMO and gap energy (Eg) changes were considerable. Gap energy decreased from 4.214 eV to 2.022 eV during the formation of complex PCB-153-SW-B80N80 nanotube that leads to conversion of PCB-153 into the other products. According to thermodynamic parameter calculation through the IR-DFT method, it is expected that SW-B80N80 nanotube will be a suitable candidate in the elimination of PCB-153, as well as a gas sensor. 相似文献
89.
Seyed Hamid Reza Pasandideh Seyed Taghi Akhavan Niaki Leila Maleki 《The International Journal of Advanced Manufacturing Technology》2014,73(9-12):1373-1385
In this research, a manufacturing facility with independent workstations to remanufacture nonconforming products is investigated. Each workstation is first modeled as an M/M/m queuing system with m being a decision variable. Then, a tri-objective integer nonlinear programming models is developed to formulate the problem. The first objective tries to minimize the waiting times of products, while the second one tries to maximize the minimum reliability of machines at the workstations. Since minimization of the waiting times results in using a large number of machines with higher idle times, the third objective is considered to minimize the mean idle time of the machines. The aim is to determine optimal number of machines at each workstation. Since the problem belongs to the class of NP-hard problems, the non-dominated sorting genetic algorithm-II (NSGA-II) is utilized to find Pareto fronts. Because there is no benchmark available in the literature to validate the results obtained, the non-dominated ranked genetic algorithm (NRGA) is used as well. In both algorithms, not only the best operators are selected but also all of their important parameters are calibrated using statistical analysis. The performances of the algorithms are statistically compared using the t test. Besides, the multiple attribute decision-making method of TOPSIS is used to determine the better algorithm. The applicability of the proposed model and the solution algorithms is demonstrated via some illustrative examples. 相似文献
90.
Maghraoui S Ayadi A Audinot JN Ben Ammar A Jaafoura MH El Hili A Migeon HN Tekaya L 《Microscopy research and technique》2012,75(2):182-188
The subcellular behavior of aluminum and indium, used in medical and industrial fields, was studied in the gastric mucosa and the liver after their intragastric administration to rats, using, two of the most sensitive methods of observation and microanalysis, the transmission electron microscopy, and the secondary ion mass spectrometry. The ultrastructural study showed the presence of electron dense deposits, in the lysosomes of parietal and principal gastric mucosa cells but no loaded lysosomes were observed in the different studied hepatic territories. The microanalytical study allowed the identification of the chemical species present in those deposits as aluminum or indium isotopes and the cartography of their distribution. No modification was observed in control rats tissues. In comparison to previous studies describing the mechanism of aluminum concentration in the gastric mucosa and showing that this element was concentrated in the lysosomes of fundic and antral human gastric mucosa, our study provided additional informations about the types of cells involved in the phenomenon of concentration of aluminum and indium, which are the parietal and the principal cells of the gastric mucosa. Our study demonstrated that these cells have the ability to concentrate selectively aluminum and indium in their lysosomes, as a defensive reaction against intoxication by foreign elements. 相似文献