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1.
The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem.  相似文献   
2.
Distributed uplink scheduling in OFDMA systems is considered. In the proposed model, mobile terminals have the responsibility of making their own transmission decisions. The proposed scheme is based on two dimensional reservation in time and frequency. Terminals use channel state information in order to favor transmissions over certain subchannels, and transmission is done in a probabilistic manner. The proposed approach provides more autonomy to mobile devices in making transmission decisions. Furthermore, it allows avoiding collisions during transmission since it leads to collision detection during the resource reservation phase. The proposed approach is compared to other random access methods and shown to be superior in terms of increasing sum-rate, reducing the number of users in outage, and reducing the collision probability in the reservation phase.  相似文献   
3.
In light of the coronavirus disease 2019 (COVID-19) outbreak caused by the novel coronavirus, companies and institutions have instructed their employees to work from home as a precautionary measure to reduce the risk of contagion. Employees, however, have been exposed to different security risks because of working from home. Moreover, the rapid global spread of COVID-19 has increased the volume of data generated from various sources. Working from home depends mainly on cloud computing (CC) applications that help employees to efficiently accomplish their tasks. The cloud computing environment (CCE) is an unsung hero in the COVID-19 pandemic crisis. It consists of the fast-paced practices for services that reflect the trend of rapidly deployable applications for maintaining data. Despite the increase in the use of CC applications, there is an ongoing research challenge in the domains of CCE concerning data, guaranteeing security, and the availability of CC applications. This paper, to the best of our knowledge, is the first paper that thoroughly explains the impact of the COVID-19 pandemic on CCE. Additionally, this paper also highlights the security risks of working from home during the COVID-19 pandemic.  相似文献   
4.
Several million tonnes of oil sands coke are generated each year in Alberta, Canada as a by-product of bitumen upgrading. Due to its high carbon content, oil sands coke can be a suitable precursor for the preparation of activated carbon. In this study, delayed and fluid oil sands coke were physically activated in a muffle furnace under select conditions of activation time (2–6 h), temperature (800–900 °C), steam rate (0.3–0.5 mL/min), and activation atmosphere (CO2, CO2 + steam, and N2 + steam). The activated products were characterized using thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, nitrogen adsorption, iodine and methylene blue tests. An increase in activation time and temperature resulted in higher surface areas in both delayed and fluid coke due to an enhanced etching of pores. An increase in steam rate led to the production of the highest specific surface area (577 m2/g) and iodine number (670 mg/g) within delayed coke; whereas, a lower steam rate resulted in the production of the highest specific surface area (533 m2/g) and iodine number (530 mg/g) in activated fluid coke samples.  相似文献   
5.
Wool fabrics were exposed to ultraviolet (UV)–ozone treatment for different periods. After exposure, the fabrics were analyzed by Fourior transform infrared spectroscopy (FTIR). Also, the crystallinity and amorphousity regions were followed by an X‐ray diffraction technique. The results were correlated by mechanical properties measurements. After a certain period of exposure, the dyeability and printability were improved because these abilities are strongly related to the percentage ratio of crystallinity regions to amorphousity regions in wool fabrics. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1469–1476, 2002  相似文献   
6.
A systematic dielectric study over the frequency range from 0.1 to 10 MHz has been carried out on pure and doped poly(methyl methacrylate) (PMMA) with tetracyanoquinodimethane (TCNQ) as an acceptor and rhodamine-6G (Rh-6G) and rhodamine-B (Rh-B) as donors before and after being exposed to γ-irradiation. The results indicate that the addition of TCNQ to PMMA increases its ability to withstand γ-irradiation and improves its insulation properties.  相似文献   
7.
This article presents a method to precipitate zinc (lignin/silica/fatty acids) complex (Zn LSF complex) from the black liquor of pulped rice straw and studying the efficiency of it as green activator and antioxidant in natural rubber composites. The results obtained revealed that the investigated zinc complex has dual function as activator and antioxidant in natural rubber composites. This evaluation was supported by physico‐mechanical properties of the vulcanizates which showed a considerable improvement of rheometric characteristics, tensile strength, strain at break, hardness, Young's modulus, thermal oxidative aging, and thermal stability of NR composites. The composite loaded with 7 phr of Zn LSF complex as activator exhibited the best mechanical properties in comparison with the same concentrations of control activator zinc stearate. Also, results revealed that Zn LSF complex is efficient as antioxidant in NR vulcanizates compared conventional antioxidants, namely polymerized 2,2,4‐trimethyl‐1,2‐dihydroquinoline. POLYM. ENG. SCI., 59:E196–E205, 2019. © 2018 Society of Plastics Engineers  相似文献   
8.
Indexing sequences containing multiple moving objects by all features of these objects captured at every clock tick results in huge index structures due to the large number of extracted features in all sampled instances. Thus, the main problems with current systems that index sequences containing multiple moving objects are: huge storage requirements for index structures, slow search time and low accuracy due to lack of representation of the time-varying features of objects. In this paper, a technique called cTraj to address these problems is proposed. For each object in a sequence, cTraj captures the features at sampled instances. Then, it maps the object??s features at each sampled instance from high-dimensional feature space into a point in low-dimensional distance space. The sequence of points of an object in low-dimensional space is considered the time-varying feature trajectory of the object. To reduce storage requirements of an index structure, the sequence of points in each trajectory is represented by a minimum bounding box (MBB). cTraj indexes a sequence by the MBBs of its objects using a spatial access method (SAM), such as an R?tree; thus, greatly reducing storage requirements of the index and speeding up the search time. The cTraj technique does not result in any false dismissal, but the result might contain a few false alarms, which are removed by a two-step refinement process. The experiments show that the proposed cTraj technique produces effective results comparable to those of a sequential method, however much more efficient.  相似文献   
9.
Distributed uplink scheduling and rate control in CDMA networks are considered in the case of adaptive antenna arrays present at the base station. The system model with omnidirectional antennas is generalized to the case where adaptive antenna arrays are deployed. Rate control in a probabilistic manner is investigated. Long-term control by the base station through token bucket constraints is incorporated in the system. Monte Carlo simulation results show considerable improvement when adaptive antenna arrays are used. Optimization of the rate transition probabilities is treated in the special case of on–off scheduling.  相似文献   
10.
Fully autotrophic nitrogen removal processes, such as the combined SHARON-Anammox process, help to improve the sustainability of wastewater treatment. Successful operation of such a completely autotrophic system is, among others, based on the strict control of the SHARON reactor in order to produce an Anammox-suited influent with a 1:1 ammonium:nitrite ratio. The high quality and high frequency measurements provided by a titrimetric set-up measuring the total ammonium (TAN) and total nitrite (TNO2) concentrations facilitate this control considerably. In this study, the use of a titrimetric set-up for monitoring the combined SHARON-Anammox process is investigated. The technique that interprets on-line collected titration curves was applied to a lab-scale system. Comparison with classic colorimetric results gave statistically indistinguishable results for TAN and TNO2 concentrations in the SHARON reactor. In the Anammox reactor, only TAN could be determined by the investigated method due to the very low TNO2 concentrations. Phosphate, a potential inhibitor of the Anammox process, is available as an additional measurement in the effluent of the SHARON reactor. Three measurements are thus combined in one single instrument. The proposed measuring technique holds different advantages over the other TAN and TNO2 measurement techniques such as on-site availability, easy automation, the absence of the need for high dilutions and cost reduction.  相似文献   
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