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71.
Vitturi S. Carreras I. Miorandi D. Schenato L. Sona A. 《Industrial Informatics, IEEE Transactions on》2007,3(4):275-288
Several recent studies have addressed the suitability of current wireless technologies for industrial communications which, frequently, are requested to cope with severe timing constraints. Most of the analysis that have lately appeared in the literature have focused on the performance offered by the lower layers of the communication stack. However, in order to obtain a complete picture, it is important to analyze how this gets coupled with the features of higher layer protocols typically employed by industrial communication applications. In this paper, we investigate the performance obtained by an application layer protocol, derived from those currently employed by wired fieldbuses, running over COTS devices based on two popular wireless communication standards, namely, IEEE 802.15.4 and IEEE 802.11. In particular, we present a mapping of the application service elements onto the services offered by the mentioned wireless systems and discuss some possible design choices. A prototype of the application layer protocol is then implemented for each considered wireless technology and the performance figures evaluated by means of experimental measurements. 相似文献
72.
Methyl tert-butylether (MTBE) used as fuel oxygenate poses problems for water suppliers since it is persistent in the aquatic environment and the removal efficiency by conventional water treatment methods (aeration or activated carbon filtration) is rather low. Substitution by other ether compounds such as ethyl tert-butylether (ETBE), tert-amylmethylether (TAME) or di-isopropylether (DIPE) is discussed, however, their environmental behaviour is similar to that of MTBE. Experiments investigating the elimination efficiency of AOP were carried out in tap water and water from Lake Constance. The elimination efficiency for all treatment processes was found to follow the order: MTBE < TAME approximately equal ETBE < DIPE For all compounds under investigation, neither pure ozonation nor UV irradiation yield a considerable concentration decline. Only the formation of highly reactive OH radicals shows a potential for removing the ethers from water. Therefore the addition of H2O2 in equimolar ratio prior to ozone admixing proved to be quite efficient. The application of combined UV/H2O2 showed good results in all cases; the best concentration decline was achieved with UV/ozone. The rate of elimination of the three substitutes for MTBE (ETBE, TAME and DIPE) is higher in all processes; nevertheless, no complete removal could be achieved. Therefore, from the point of view of water suppliers, the use of other ethers as substitute for MTBE is posing the same problems as MTBE. 相似文献
73.
This paper propose a first approach to deal with contextual information in structured domains by recursive neural networks. The proposed model, i.e., contextual recursive cascade correlation (CRCC), a generalization of the recursive cascade correlation (RCC) model, is able to partially remove the causality assumption by exploiting contextual information stored in frozen units. We formally characterize the properties of CRCC showing that it is able to compute contextual transductions and also some causal supersource transductions that RCC cannot compute. Experimental results on controlled sequences and on a real-world task involving chemical structures confirm the computational limitations of RCC, while assessing the efficiency and efficacy of CRCC in dealing both with pure causal and contextual prediction tasks. Moreover, results obtained for the real-world task show the superiority of the proposed approach versus RCC when exploring a task for which it is not known whether the structural causality assumption holds. 相似文献
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75.
Gohar Tsakanova Nelly Babayan Elena Karalova Lina Hakobyan Liana Abroyan Aida Avetisyan Hranush Avagyan Sona Hakobyan Arpine Poghosyan Bagrat Baghdasaryan Elina Arakelova Violetta Ayvazyan Lusine Matevosyan Arpine Navasardyan Hakob Davtyan Lilit Apresyan Arsham Yeremyan Rouben Aroutiounian Andreyan N. Osipov Bagrat Grigoryan Zaven Karalyan 《International journal of molecular sciences》2021,22(21)
The development of new laser-driven electron linear accelerators, providing unique ultrashort pulsed electron beams (UPEBs) with low repetition rates, opens new opportunities for radiotherapy and new fronts for radiobiological research in general. Considering the growing interest in the application of UPEBs in radiation biology and medicine, the aim of this study was to reveal the changes in immune system in response to low-energy laser-driven UPEB whole-body irradiation in rodents. Forty male albino Wistar rats were exposed to laser-driven UPEB irradiation, after which different immunological parameters were studied on the 1st, 3rd, 7th, 14th, and 28th day after irradiation. According to the results, this type of irradiation induces alterations in the rat immune system, particularly by increasing the production of pro- and anti-inflammatory cytokines and elevating the DNA damage rate. Moreover, such an immune response reaches its maximal levels on the third day after laser-driven UPEB whole-body irradiation, showing partial recovery on subsequent days with a total recovery on the 28th day. The results of this study provide valuable insight into the effect of laser-driven UPEB whole-body irradiation on the immune system of the animals and support further animal experiments on the role of this novel type of irradiation. 相似文献
76.
Sona Chavoshizadeh Sajad Pirsa Forough Mohtarami 《European Journal of Lipid Science and Technology》2020,122(3)
In this study, a smart biodegradable film based on wheat gluten modified with chlorophyll (WG/Ch) is presented. The effect of chlorophyll on the antioxidant activity and mechanical properties of WG/Ch film is studied. Scanning electron microscopy and Fourier‐transform infrared spectroscopy (FT‐IR) analyses are used to study the structure and chemical composition of gluten‐based films. The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on increasing the shelf life and detecting expiration time of oil is studied. FT‐IR results show that weak interactions are created between gluten and chlorophyll. The antioxidant activity of the WG film is 60% and it increases to 85% by the addition of chlorophyll. The results show that with the increasing storage time of oil samples, oxidative indices are increased, but the WG/Ch film decreases the sesame oil oxidation significantly (almost in the all oxidative indices 50% decrease is observed). Practical Applications: The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on the increasing of shelf life and detecting expiration time of oil is studied. By increasing storage time and oxidant, acidity, acid number, PA, and oil color change are increased, but the WG/Ch active film decreases the sesame oil oxidation significantly. Also, by examining the color properties of the active film, it is observed that with increasing storage time and oxidant percent, the color of the film is changed (from green to yellow), which can be used to estimate the oil expiration time. It should be mentioned that the film's color changes are visible to the naked eye. 相似文献
77.
Young-Min Kong Sona Kim Hyoun-Ee Kim In-Seop Lee 《Journal of the American Ceramic Society》1999,82(11):2963-2968
The mechanical properties of hydroxyapatite (HAp) bioceramic material were improved significantly by adding tetragonal-zirconia-polycrystalline (TZP) powder coated with Al2 O3 . The coating was done by dispersing the TZP powder in a boehmite suspension and adjusting the pH to cause heterocoagulation. The coating effectively reduced the deleterious reaction between the HAp and the TZP that tended to form tricalcium phosphate (TCP) and fully stabilized cubic zirconia. When 15 vol% zirconia and 30 vol% alumina were added to the HAp by the coating method, the strength and the fracture toughness of the composite were 300 MPa and 3 MPa·m1/2 , respectively, which are about 3 times higher than those of pure HAp. 相似文献
78.
Bertocco M. Sona A. Zanchetta P. 《IEEE transactions on instrumentation and measurement》2007,56(4):1165-1170
This paper discusses issues in the uncertainty of power measurement performed with a superheterodyne spectrum analyzer. In particular, the channel power technique is considered, and an original and effective method is proposed based on the "Guide to the Expression of Uncertainty in Measurement" for the uncertainty evaluation of channel power measurement. The method is based on the measurement of some suitable parameters associated to the input signal's spectrum and the use of a proper postprocessing formula. It allows a user to greatly simplify the computation of measurement uncertainty without loss of accuracy. The effectiveness of the method is verified experimentally. In particular, experiments are performed involving both laboratory- generated signals and some typical real-world digital communication signals. Helpful information and hints for the optimization of the spectrum analyzer setup and the reduction of uncertainty are Anally provided. 相似文献
79.
Atkins David C.; Dimidjian Sona; Bedics Jamie D.; Christensen Andrew 《Canadian Metallurgical Quarterly》2009,77(6):1089
The association between depression and relationship distress as well as the impact of treatment for the one on the other was examined across 2 treatment-seeking samples: individuals seeking treatment for depression (N = 120) and couples seeking marital therapy (N = 134 couples). Although there was a baseline association between depression and distress across the 2 samples, relationship distress was far more prevalent among those being treated for depression than was depression for those seeking marital therapy. There was a reliable association between changes in the primary problem (e.g., relationship distress in the couple therapy study) and changes in the secondary problem (e.g., depression in the couple therapy study). However, overall effects on secondary problems were quite small. Neuroticism played a complex, moderating role across the 2 samples, strengthening and weakening the association between depression and relationship distress depending on the sample and gender, replicating previous findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.