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801.
Fuzzy Adaptive Control of a Fractional Order Chaotic System With Unknown Control Gain Sign Using a Fractional Order Nussbaum Gain
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Khatir Khettab Samir Ladaci Yassine Bensafia 《IEEE/CAA Journal of Automatica Sinica》2019,6(3):816-823
In this paper we propose an improved fuzzy adaptive control strategy, for a class of nonlinear chaotic fractional order (SISO) systems with unknown control gain sign. The online control algorithm uses fuzzy logic sets for the identification of the fractional order chaotic system, whereas the lack of a priori knowledge on the control directions is solved by introducing a fractional order Nussbaum gain. Based on Lyapunov stability theorem, stability analysis is performed for the proposed control method for an acceptable synchronization error level. In this work, the Grünwald-Letnikov method is used for numerical approximation of the fractional order systems. A simulation example is given to illustrate the effectiveness of the proposed control scheme. 相似文献
802.
Many previous research studies have demonstrated game strategies enabling virtual players to play and take actions mimicking humans. The Case-Based Reasoning (CBR) strategy tries to simulate human thinking regarding solving problems based on constructed knowledge. This paper suggests a new Action-Based Reasoning (ABR) strategy for a chess engine. This strategy mimics human experts’ approaches when playing chess, with the help of the CBR phases. This proposed engine consists of the following processes. Firstly, an action library compiled by parsing many grandmasters’ cases with their actions from different games is built. Secondly, this library reduces the search space by using two filtration steps based on the defined action-based and encoding-based similarity schemes. Thirdly, the minimax search tree is fed with a list extracted from the filtering stage using the alpha-beta algorithm to prune the search. The proposed evaluation function estimates the retrievably reactive moves. Finally, the best move will be selected, played on the board, and stored in the action library for future use. Many experiments were conducted to evaluate the performance of the proposed engine. Moreover, the engine played 200 games against Rybka 2.3.2a scoring 2500, 2300, 2100, and 1900 rating points. Moreover, they used the Bayeselo tool to estimate these rating points of the engine. The results illustrated that the proposed approach achieved high rating points, reaching as high as 2483 points. 相似文献
803.
Salsabeel N. El Gendy Amira K. Elmotayam Reham Samir Marwa I. Ezzat Aly M. El Sayed 《Journal of the American Oil Chemists' Society》2023,100(8):591-614
Simmondsia chinensis (Link) C.K. Schneider (Jojoba) is a valuable shrub that can bear harsh conditions and is cultivated in many countries globally. Its prominence originates from the unique oil that constitutes more than 50% of the seeds. The great economic value of jojoba oil is highlighted in many fields, especially the cosmetic industry. The remaining meal, which is rich in proteins, constitutes a good source for cattle feeding. However, the presence of antinutritional principles in the meal limited its use and encouraged the researchers to find different ways for its detoxification. The detoxification ways of jojoba meal included physical, biological, and chemical treatments. The phytochemical composition of the oil was deeply studied, but for the remaining plant, only few studies have reported its chemical composition. Jojoba oil composed of wax esters (97%), fatty acids, fatty alcohols, sterols, and small percentage of vitamin E. Jojoba possesses a long traditional history. It has been used in folklore for treatment of cold, dysuria, and obesity. Many recent studies reported its medicinal and pharmacological properties like antioxidant, anti-inflammatory, antimicrobial, anticancer, anti-acne, anti-psoriasis, wound healing, and hepatoprotective activities. Many of these biological activities have been attributed to the presence of several phytochemicals such as simmondsin and phenolic compounds. In this review, the authors will highlight the previous phytochemical studies, medicinal applications of jojoba oil and different plant parts, and the various ways of meal detoxification. 相似文献
804.
Biswajit Samir De Ram Ji Dixit Abhas Anand Vicky Rahul Dhongde Suddhasatwa Basu 《加拿大化工杂志》2023,101(6):3167-3179
Electrochemical conversion of biomass to value-added chemicals has gained impetus in recent years. Herein, we present a methodology for recovering biomass-derived 2-furoic acid from the dilute aqueous stream by reactive extraction. The reactive extraction was performed using a chemical extractant, trioctylamine (TOA), with diluents (octanol, chloroform, and diethyl ether). Equilibrium parameters influencing the recovery of 2-furoic acid were evaluated. Using TOA in various diluents, the 2-furoic acid was recovered with 85%–99% efficiency. A 1:1 complex of the 2-furoic acid—TOA was formed in the organic phase, and the experimental equilibrium complexation constant was compared with that obtained from the relative basicity and Langmuir models. The equilibrium parameters were used for column design to estimate the solvent to feed ratio (S/F) and the number of theoretical stages (NTS). The NTS required is 12 to attain 99% recovery of 2-furoic acid in counter-current extraction. The present study sheds light on the reactive extraction process adopted for process intensification with electrochemical conversion, paving the way for the commercialization of valuable products obtained from biomass. 相似文献
805.
Ria Ghosh Soumendra Singh Dipanjan Mukherjee Susmita Mondal Monojit Das Uttam Pal Aniruddha Adhikari Aman Bhushan Surajit Bose Siddharth Sankar Bhattacharyya Debasish Pal Tanusri Saha-Dasgupta Maitree Bhattacharyya Debasis Bhattacharyya Asim Kumar Mallick Ranjan Das Samir Kumar Pal 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200109
Drug delivery to a target without adverse effects is one of the major criteria for clinical use. Herein, we have made an attempt to explore the delivery efficacy of SDS surfactant in a monomer and micellar stage during the delivery of the model drug, Toluidine Blue (TB) from the micellar cavity to DNA. Molecular recognition of pre-micellar SDS encapsulated TB with DNA occurs at a rate constant of k1 ∼652 s−1. However, no significant release of encapsulated TB at micellar concentration was observed within the experimental time frame. This originated from the higher binding affinity of TB towards the nano-cavity of SDS at micellar concentration which does not allow the delivery of TB from the nano-cavity of SDS micelles to DNA. Thus, molecular recognition controls the extent of DNA recognition by TB which in turn modulates the rate of delivery of TB from SDS in a concentration-dependent manner. 相似文献
806.
Sayed M. Hegazi Mohamed S. Foda Sayed A. Salem Samir M. Badr Eldin 《Starch - St?rke》1973,25(3):92-94
Precipitates containing 47.7% and 30.5% protein were isolated from rice starch steep and sorter liquors respectively by pH adjustment of these liquors. The pH for protein precipitation from the steep liquor was 7.0 and from the sorter liquor was 5.0. The acid hydrolysates of both precipitates contained at least seventeen amino acids, Glutamic acid and arginine constitute the largest proportions of these acids. Nine essential amino acids were found to be present in variable amounts. The industrial application of this method for the preparation of protein precipitates is discussed. 相似文献
807.
Silicon - The purpose of this work is to predict the existence of novel equiatomic SiCN based on tetragonal C6 structure the elementary building unit being the 1,4 cyclohexadiene molecule... 相似文献
808.
Dyhia Sadou Nadia Amessis-Ouchemoukh Salim Ouchemoukh Rabha Ayad Nawel Guenaoui Amar Otmani Mostapha Bachir-bey Samir Hadjal Khodir Madani 《European Journal of Lipid Science and Technology》2023,125(11):2300081
This study focused on the use of lentisk oil and honey as natural sources to formulate margarine with ameliorated quality and oxidative stability. For this, five margarines were formulated with honey and different concentrations of lentisk oil. Analyses were performed on oil and honey used, and then physicochemical characterization and several oxidative stability tests were applied to assess margarine quality. The results showed a significant richness of lentisk oil and honey in total phenolics and total flavonoids and expressed good antioxidant activities. As well as the evaluation of oxidative stability of enriched margarines during 3 months of storage demonstrated that margarine added with 2% lentisk oil (M1) had the best resistance properties and longer Rancimat induction time (22.26 h), better than the control and margarines added with 5% (M2), 10% (M3), and 15% (M4) lentisk oil. Globally, margarines prepared with high concentrations of lentisk oil (M2–M4) were not different from the control, whereas only M1 was permitted to ameliorate the stability of margarine with a slight influence on physicochemical parameters. The elaboration of margarine supplemented with 2% lentisk oil improves the properties of the product, which could then be applied to margarine manufacturing. 相似文献
809.
Samir A.A. El-Gendy Mohamed A.M. Alsafy Catrin S. Rutland Samar M. Ez Elarab Hanan H. Abd-Elhafeez Basma M. Kamal 《Microscopy research and technique》2023,86(1):53-62
The present study describes the morphological characteristics of the camel heart Ossa cordis, and os aorta using computed tomography soft tissue window (CT) alongside 3D render volume reconstructions and light microscopy. The current study techniques demonstrated the Ossa cordis and os aorta in the cardiac window with more precision than the black and white (ghost), and angiography images. Transverse and sagittal CT images additionally demonstrated the presence of Ossa cordis and os aorta. This study is the first to record two small Ossa cordis sinistrum and one os aorta in the camel heart, in addition to the more commonly observed singular, large, os cordis dextrum. The os cordis dextrum was always located in the upper part of the interventricular septum, near to its junction with the atrium, forming an elongated rectangular shape when observed transversally. The wider cranial part was composed from bone, whereas the caudal aspect was narrow and contained both bone and cartilage. Light microscopy identified that the os cordis dextrum consisted of trabecular bone, marrow spaces, and hyaline cartilage. Two Ossa cordis sinistrum were detected on the left side of the heart, one in the right fibrous ring and another in the interventricular septum, microscopy showed that both contained only trabecular bone with osteocytes, osteoblasts, and osteoclasts. At the level of ascending aorta, there was also trabecular bone containing osteocytes, an os aorta. 相似文献
810.
Glass fiber reinforced polymer composite (GFRP) encounter many practical situations during its application, exposed to different temperature fluctuation. Absorption of moisture and the fluctuated thermal environment cause mechanical degradation of GFRP. The current plan is to explore the mechanical and chemical behavior of pristine multiwall carbon nanotubes(pMWCNTs)-glass fiber strengthens epoxy composites during thermal shock (TS). The laminates were prepared by the hand-lay-up process followed by compression molding. The thermal shock was performed at the temperature for the required samples was 135°C for 24 h, followed by −135°C for 24 h. A flexural test has been carried out at 1 mm/min loading speed. 0.2 wt% pMWCNTs filled nanocomposite appeared to have the highest flexural strength and modulus compared to ambient samples. The thermomechanical behavior of nanocomposites has been accomplished by analyzing the dynamic mechanical thermal analysis graph (DMTA). Field emission scanning electron microscope (FESEM) analyzed the fracture surface of in-situ mechanical failure samples to find out the primary failure modes for strengthening and weakening mechanisms. The glass transition temperature (Tg) of the nanocomposite observed decreased due to homogeneous dispersion of pMWCNTs, imparting some effect on crosslink density and reinforcement up to 0.2 wt%. This study reveals that the uniform distribution of pMWCNTs and thermal shock treatment enhances the matrix stiffness and improves the mechanical properties. 相似文献