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41.
Ibrahim M. Alwayle Badriyya B. Al-onazi Jaber S. Alzahrani Khaled M. Alalayah Khadija M. Alaidarous Ibrahim Abdulrab Ahmed Mahmoud Othman Abdelwahed Motwakel 《计算机系统科学与工程》2023,46(3):3423-3438
Arabic is one of the most spoken languages across the globe. However, there are fewer studies concerning Sentiment Analysis (SA) in Arabic. In recent years, the detected sentiments and emotions expressed in tweets have received significant interest. The substantial role played by the Arab region in international politics and the global economy has urged the need to examine the sentiments and emotions in the Arabic language. Two common models are available: Machine Learning and lexicon-based approaches to address emotion classification problems. With this motivation, the current research article develops a Teaching and Learning Optimization with Machine Learning Based Emotion Recognition and Classification (TLBOML-ERC) model for Sentiment Analysis on tweets made in the Arabic language. The presented TLBOML-ERC model focuses on recognising emotions and sentiments expressed in Arabic tweets. To attain this, the proposed TLBOML-ERC model initially carries out data pre-processing and a Continuous Bag Of Words (CBOW)-based word embedding process. In addition, Denoising Autoencoder (DAE) model is also exploited to categorise different emotions expressed in Arabic tweets. To improve the efficacy of the DAE model, the Teaching and Learning-based Optimization (TLBO) algorithm is utilized to optimize the parameters. The proposed TLBOML-ERC method was experimentally validated with the help of an Arabic tweets dataset. The obtained results show the promising performance of the proposed TLBOML-ERC model on Arabic emotion classification. 相似文献
42.
Discrete second‐order sliding mode control based on optimal sliding function vector for multivariable systems with input–output representation
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The technique of linear matrix inequalities is a powerful method for solving optimization problems. In this paper, a sliding function vector was calculated using linear matrix inequalities approach. This technique provided optimal values of the coefficients of the sliding function vector, which led to the reduction of the reachability phase. Then, a discrete second‐order sliding mode control for multivariable systems was developed using this optimal sliding function vector. Two examples were used in order to illustrate the effectiveness of the proposed strategy. Simulation results prove good performances in terms of reduction of the reachability phase. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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44.
In this article, a study of the aging of conducting Polyaniline–Polystyrene blends using X‐ray photoelectron spectroscopy (XPS) and UV‐visible‐near IR analysis is presented. The physicochemical results are compared to those obtained by electrical measurements. XPS results confirm the existence of an oxidation process also deduced by the electrical conductivity studies. The N1s and S2p core level spectra decomposition allows to show that a deprotonation process and cyclization of tertiary amine occur during aging. The absorption spectrum shows a decrease of delocalized charges and the apparition of localized polarons after a long aging time. All these mechanisms are responsible of the electrical conductivity decrease observed during aging at elevated temperature. The results are presented for films of PANI–CSA–PSt blends, but the conclusions can be extended to pure conducting PANI–CSA films. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3730–3736, 2003 相似文献
45.
Moza Al-Busaidi Waleed Al-Rabhi Khadija Al-Harthy Aaliah Al-Waili Nashwa Al-Mazrooei 《International Journal of Food Properties》2013,16(12):2764-2775
Fresh yellowfin tuna (n = 110) collected for a period of one year was analyzed for chemical composition, fatty acids, nutrients, and toxic metals. The mean values of investigated minerals were 892, 2834, 0.81, 6.61, 0.38, 11.0, 0.94, 0.59, 0.71, 0.53, and 0.29 mg kg–1 for Na, K, Cu, Zn, Mn, Fe, Ni, Co, Cr, Sr, and V, respectively. Average Cd, Pb and Hg levels were 0.016, 0.029 and 0.137 mg kg?1, respectively. The average concentrations of saturated, monounsaturated, and polyunsaturated fatty acids were 196.56, 84.8, and 218 mg 100g–1, respectively. Yellowfin tuna contained higher DHA (148.2 mg 100g–1) than EPA (29.3 mg 100 g–1). A meal with 100 g of this species provides 48.6 and 71.05% of the required daily level of protein and EPA+DHA, respectively. Yellowfin tuna showed low thrombogenic (0.27) and atherogenic (0.43) potential and the value obtained for h/H index (1.97) indicates that regular intake of yellowfin tuna may bring hypocholesterolemic effect. All contaminants in the studied fish were either undetectable or present at very low levels when compared to the United States Food and Drug Administration (USFDA), Food and Agriculture Organization/World Health Organization (FAO/WHO), and European Union regulatory standards and yellowfin tuna would be one of the best options for people who frequently consume tuna fish to get sufficient EPA+DHA and essential elements. 相似文献
46.
In this article, a study of the thermal behavior of polyaniline films and polyaniline–polystyrene blends is presented. Transport measurements (electrical conductivity and thermoelectric power) at high temperature and thermogravimetric analysis show that an irreversible degradation is observed near 450 K for films doped with DiOHP and near 500 K for films doped with CSA. In both cases, the thermoelectric power is the most sensitive parameter to electrical degradation during the heating of conducting films. Electrical conductivity measurements during heating–cooling cycles show a diminution of the room temperature conductivity after evaporation of the solvent (water, m‐cresol). A model of cluster with a variable diameter allows interpreting this phenomenon by assuming the existence of a sensitive frontier to the solvent at the periphery of conducting clusters. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1848–1855, 2002; DOI 10.1002/app.10468 相似文献
47.
A. Amara W. Rezaiki A. Ferdi A. Hendaoui A. Drici M. Guerioune J.C. Bernde M. Morsli 《Solar Energy Materials & Solar Cells》2007,91(20):1916-1921
Single crystals CuInS2 were grown by iodine vapour transport method, whereas polycrystalline thin films were obtained by coevaporation technique from three sources. The temperature dependence of the hole mobility in valence band is analysed by taking into account contributions from several scattering mechanisms of the charge carriers. To account for the temperature dependant conductivity of polycrystalline CuInS2 thin films, grainboundary conduction process was suggested. In the low temperature region, we interpret the data in terms of the Mott law and the analysis is very consistent with the variable range hopping. However, thermionic emission is predominant at high temperatures. Photoluminescence measurements have been performed on CuInS2 crystals and the analysis has revealed that the emission is mainly due to free-to-bound and donor–acceptor pair transitions. The band gap of that compound is derived from the excitonic emission line at 1.53 eV. 相似文献
48.
Tarrass F Benjelloun M Medkouri G Hachim K Benghanem MG Ramdani B 《Hemodialysis international. International Symposium on Home Hemodialysis》2006,10(4):356-359
Pulmonary hypertension (PH) has been reported in hemodialysis (HD) patients, but data regarding its incidence and mechanisms are scarce. The aims of this study was to evaluate the prevalence of unexplained PH in long-term HD patients, and to examine some possible etiologic factors for its occurrence. The prevalence of PH was estimated by Doppler echocardiography in a cohort of 86 stable patients on HD via arteriovenous access for more than 12 months. All the patients underwent full clinical evaluation, chest radiography, and a standard 12-lead echocardiograph. Laboratory investigation included a mean of 12 months (serum calcium, phosphorus, parathormone (PTH), alkaline phosphatase, lipids, and hemoglobin). Pulmonary hypertension was defined as pulmonary artery systolic pressure >35 mmHg as determined by Doppler echocardiography using the modified Bernoulli equation. Pulmonary hypertension was detected in 23 patients (26.74%). Of those with PH, left ventricular hypertrophy was seen in 13 patients (56.52%), and valvular calcifications in 6 patients (26.08%). There were no significant differences between both groups with regard to age, sex, duration of dialysis, shunt location, and all the biological parameters of the study. The presence of PH was not related to the level of PTH, or the severity of other metabolic abnormalities. This study demonstrates a high prevalence of PH among patients with ESRD receiving long-term HD via surgical arteriovenous access. The role of the vascular access, anemia, or secondary hyperparathyroidism as the etiology of PH in HD patients did not hold in this study. 相似文献
49.
Potter RB Darmame K Nortcliff S 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2010,368(1931):5299-5313
Over the last two decades, Jordan has suffered a chronic water crisis, and is the tenth most water-scarce nation on Earth. Such water stress has been well illustrated in the case of Greater Amman, the capital, which has grown dramatically from a population of around 2000 in the 1920s, to 2.17 million today. One of the distinctive characteristics of the water supply regime of Greater Amman is that since 1987 it has been based on a system of rationing, with households receiving water once a week for various durations. Amman is highly polarized socio-economically, and by means of household surveys, both quantitative and qualitative, conducted in high- and low-income divisions of the city, a detailed empirical evaluation of the storage and use of water, the strategies used by households to manage water and overall satisfaction with water supply issues is provided in this paper, looking specifically at issues of social equity. The analysis demonstrates the social and economic costs of water rationing and consequent management to be high, as well as emphasizing that issues of water quality are of central importance to all consumers regardless of their socio-economic status within the city. 相似文献
50.
Lubna Naheed Miriam Koppel Maarja Paalo Khadija Alsabawi Krystina E. Lamb Evan MacA. Gray Alar Jänes Colin J. Webb 《International Journal of Hydrogen Energy》2021,46(29):15761-15772
Properties of the adsorbed hydrogen phase have been studied for hydrogen adsorption in three carbide derived carbons: SiC-CDC, steam/CO2 activated SiC-CDC and TiC-CDC. Using the excess hydrogen uptake isotherm at hydrogen pressures above 120 MPa where adsorption has finished, the adsorbate volume has been determined and the adsorbate density has been calculated at ambient temperatures. Absolute adsorption isotherms have been constructed by assuming the adsorbate volume is equivalent to the pore volume and is therefore constant. This study indicates that all three CDCs had the same maximum adsorbate density, with the adsorption proportional to the total pore volume. 相似文献