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191.
Polymeric fibres are semicrystalline structures in which macromolecules are rarely oriented in their equilibrium state. Further instabilities are imparted when the fibres are converted into yarns and the yarns into fabrics. Heat setting is an important industrial process, as it reduces the fibre strain to an acceptable limit. Although this process provides dimensional stability to polyamide 6.6, yet it affects its dyeability. This paper investigates the effects of hot water setting treatment on the dyeing properties of grafted polyamide 6.6 microfibres dyed with a cationic dye. It reveals that the dye uptake of the hot water-set samples is inferior to those unset. A kinetic study showed a change in the build-up rate. In addition, an increase in the percentage of grafting improved the quantity of the dye fixed on both unset and hot water-set samples. Comparing the wash fastness of the unset samples, the hot water ones are found to be lower. The modelling of the adsorption isotherms using Langmuir, Freundlich and Jossen relations allows the determination of isotherm constants. The results obtained have been modelled using standard adsorption isotherms. 相似文献
192.
Power transformer fault diagnosis based on dissolved gas analysis by support vector machine 总被引:1,自引:0,他引:1
This paper presents an intelligent fault classification approach to power transformer dissolved gas analysis (DGA). Support vector machine (SVM) is powerful for the problem with small sampling (small amounts of training data), nonlinear and high dimension (large amounts of input data). The standard IEC 60599 proposes two DGA methods which are the ratios and graphical representation. According the experimental data, for the same input data, these two methods give two different faults diagnosis results, what brings us to a problem. This paper investigates a novel extension method which consists in elaborating an input vector establishes by the combination of ratios and graphical representation to resolve this problem. SVM is applied to establish the power transformers faults classification and to choose the most appropriate gas signature between the DGA traditional methods and a novel extension method. The experimental data from Tunisian Company of Electricity and Gas (STEG) is used to illustrate the performance of proposed SVM models. Then, the multi-layer SVM classifier is trained with the training samples. Finally, the normal state and the six fault types of transformers are identified by the trained classifier. In comparison to the results obtained from the SVM, the proposed DGA method has been shown to possess superior performance in identifying the transformer fault type. The SVM approach is compared with other AI techniques (fuzzy logic, MLP and RBF neural network); the proposed method gives a good performance for transformers fault diagnosis. The test results indicate that the novel extension method and the SVM approach can significantly improve the diagnosis accuracies for power transformer fault classification. 相似文献
193.
In this paper, we propose to analyze the binary integration of the cell-averaging constant false-alarm rate (CA-CFAR) and
order statistics constant false-alarm rate (OS-CFAR) detectors in the presence of non-Gaussian spiky clutter modeled as a
Pearson distribution. We derive new closed form expressions for false alarm and detection probabilities for the CA-CFAR detector
in the presence of Pearson-distributed clutter backgrounds. We first show that the use of binary integration improves the
detection probabilities of the detectors considered. Secondly, the maximum of detection probability occurs for an optimum
choice when the second threshold is set to be equal to M = (3/4) L. For this optimum M-out-of-L rule, the comparison analysis of the CA-CFAR and OS-CFAR binary integrators showed that the latter has better performance
in homogeneous Pearson- distributed clutter. 相似文献
194.
Wahid Herchi Faouzi Sakouhi Sebei Khaled Yeping Xiong Sadok Boukhchina Habib Kallel Jonathan M. Curtis 《Food chemistry》2011
A high-performance liquid chromatographic method coupled with mass spectrometry was used to characterise the natural phospholipid (PL) classes and molecular species in flaxseed oils. The PL fraction included phosphatidylethanolamine (PE) (27–40%), phosphatidylinositol (PI) (29–32%), phosphatidylcholine (PC) (7–18%), lysophosphatidylcholine (LPC) (8–21%), phosphatidylglycerol (PG) (1–4%) and phosphatidic acid (PA) (1–9%). The distribution of fatty acids was found to differ between phospholipids. Stearic acid was mainly present in the form of PC and LPC. Palmitic acid was present in the most abundant molecular species in PI, PG and PA whereas linoleic acid formed the most abundant molecular species in PE. 相似文献
195.
Faouzi Zarrouki Sbastien Goutal Ophlie Vacca Luis Garcia Nicolas Tournier Aurlie Goyenvalle Cyrille Vaillend 《International journal of molecular sciences》2022,23(20)
Duchenne muscular dystrophy (DMD) is a neurodevelopmental disorder primarily caused by the loss of the full-length Dp427 dystrophin in both muscle and brain. The basis of the central comorbidities in DMD is unclear. Brain dystrophin plays a role in the clustering of central gamma-aminobutyric acid A receptors (GABAARs), and its loss in the mdx mouse alters the clustering of some synaptic subunits in central inhibitory synapses. However, the diversity of GABAergic alterations in this model is still fragmentary. In this study, the analysis of in vivo PET imaging of a benzodiazepine-binding site radioligand revealed that the global density of central GABAARs is unaffected in mdx compared with WT mice. In contrast, semi-quantitative immunoblots and immunofluorescence confocal imaging in tissue sections revealed complex and differential patterns of alterations of the expression levels and/or clustered distribution of a variety of synaptic and extrasynaptic GABAAR subunits in the hippocampus, cerebellum, cortex, and spinal cord. Hence, dystrophin loss not only affects the stabilization of synaptic GABAARs but also influences the subunit composition of GABAARs subtypes at both synaptic and extrasynaptic sites. This study provides new molecular outcome measures and new routes to evaluate the impact of treatments aimed at compensating alterations of the nervous system in DMD. 相似文献
196.
Nikos Passas Sarantis Paskalis Alexandros Kaloxylos Faouzi Bader Renato Narcisi Evangelos Tsontsis Adil S. Jahan Hamid Aghvami Mirtín O'Droma Ivan Ganchev 《Wireless Communications and Mobile Computing》2006,6(4):523-540
‘Always Best Connected’ (ABC) is considered one of the main requirements for next generation networks. The ABC concept allows a person to have access to applications using the devices and network technologies that best suits his or her needs or profile at any time. Clearly, this requires the combination of a set of existing and new technologies, at all levels of the protocol stack, into one integrated system. In this paper, a considerable set of the technologies, that are expected to play a key role towards the ABC vision, are presented. Starting from a reference architecture, the paper describes the required enhancements at certain levels of a traditional protocol stack, as well as technologies for mobility and end‐to‐end Quality of Service (QoS) support. The paper concludes with a case study that reveals the advantages of the ABC concept. This article replaces a previously published version (Wireless Communications and Mobile Computing; 5 (2): 175‐191. [DOI: 10.1002/wcm.207]). Retraction notice DOI: 10.1002/wcm.426 . Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
197.
Faouzi Sakouhi Ammar Chérif Chaima Saadi Sadok Boukhchina 《European Journal of Lipid Science and Technology》2023,125(12):2300013
Bioactive compounds are components extracted from biological matrices that may offer physiological health benefits and have nutritive value. The present study characterized bioactive lipid components such as fatty acids, phytosterols, policosanol, and triterpenes from table olives. The table olives were processed according to the green Spanish-style method. The obtained results indicate that phytosterol fraction constitutes the major portion of the total unsaponifiable matter. The analysis of phytosterols showed the presence of 11 compounds, β-sitosterol the predominant one. The policosanol composition indicated that hexacosanol, tetracosanol, octacosanol, and docosanol were the main compounds, accounting for over 85% of total policosanols. Pentacyclic triterpenes (cycloartenol and 24-methylene cycloartenol) were found at a higher level (over 85%) compared to tetracyclic triterpenes (β-amyrin, δ-amyrin). These findings reveal that processed table olives contain an interesting amount of various bioactive compounds compared to marine and other floral biological matrices. Thus, processed table olives represent an interesting natural functional food that presents high stability and bioavailability of their natural bioactive ingredients. Practical Applications: Nowadays, with health food gaining popularity among consumers, the demand for natural bioactive compounds and functional food is expanding considerably all over the world. This study focuses on analyzing bioactive lipid components from processed table olives. Fruits were processed according to the green Spanish-style method. The salt content of the brine was adjusted to the minimum sodium chloride value required by the Codex Alimentarius Comission, which is 5%, taking into consideration people suffering from hypertension. This concentration is considered the minimum amount of salt necessary to exhibit antibacterial activities. Considering the results obtained, processed table olives present one of the most valuable potential resources for bioactive lipid compounds and have a considerable ability to preserve the stability of their lipid components. Thus, the food industry in Mediterranean countries can promote processed table olives as conventional functional food with no need for any enrichment or fortification. 相似文献
198.
Farhat Saida Abdelkader Manel Meddeb-Makhlouf Amel Zarai Faouzi 《International Journal of Information Security》2023,22(6):1989-2013
International Journal of Information Security - With the increasing adoption of cloud computing, securing cloud-based systems and applications has become a critical concern for almost every... 相似文献