This paper presents a new adaptive sliding mode control approach for the synchronization of the uncertain fractional-order chaotic systems. A self-structuring hierarchical type-2 fuzzy neural network ...(SHT2FNN) is proposed for estimation of uncertainties. Also the switching control action in the conventional sliding mode scheme is replaced by combination type-2 fuzzy neural network (T2FNN) with hyperbolic tangent function. In SHT2FNN, the number of rules is determined by a proposed algorithm. Adaptation laws of all trainable parameters of T2FNN and the consequent parameters of SHT2FNN, are derived based on Lyapunov stability analysis. The simulation results on two kind systems: Genio-Tesi and Coullet System and fractional-order hyper-chaotic Lorenz system, confirm the efficacy of the proposed scheme in synchronization of the uncertain fractional-order hyperchaotic and fractional-order chaotic systems.
The proposed controller is robust against the approximation error and external disturbance. The proposed self-structuring algorithm in this paper is simple and it can be applied in the high dimensional problems. Furthermore, the proposed algorithm can delete unimportant rules. Adjusting the structure of the T2FNN in the hierarchical form ensures that the estimation error is very small so it can be negligible. Furthermore, the proposed strategy guarantees the robustness of controller.
•A passive islanding detection method is presented for inverter-based DGs.•The proposed method has zero NDZ.•Islanding is detected in less than two cycles, even for zero power mismatch.•The method ...operates effectively in multi-DG systems for various conditions.
This paper presents a passive islanding detection method for inverter-based distributed generation based on empirical mode decomposition (EMD) technique. The voltage of point of common coupling (PCC) is measured and its intrinsic mode functions (IMFs) are obtained using EMD. The first IMF component of PCC per unit voltage is the parameter used for islanding detection. Performance of the proposed method is evaluated for single-DG and multi-DG cases. Simulation results performed in MATLAB/SIMULINK environment show that the islanding can be detected in less than two cycles, even for zero power mismatch. Moreover, the proposed method functions properly for various configurations of multi-DG systems, DGs switching events, various loadings of DGs and different DG interface controls.
Aims
The present study was conducted to investigate the effects of Thymus daenensis and Satureja hortensis essential oils (EOs) on the planktonic growth, biofilm formation and quorum sensing (QS) of ...some Staphylococcus aureus isolates (strong biofilm producers).
Methods and Results
Minimum inhibitory concentration (MIC) of the EOs, inhibition of biofilm formation as well as disruption of preformed Staph. aureus biofilms were assessed. The antibiofilm activity of the EOs was determined using microtitre plate test (MtP) and scanning electron microscope (SEM). The QS inhibitory activity was also examined on the pregrown biofilms by gene expression analysis using quantitative real‐time RT‐polymerase chain reaction (PCR) of hld gene (RNAIII transcript). Moreover, tetrazolium‐based colorimetric assay (MTT) was performed to detect cytotoxic effects of these EOs on the Vero cell line. Finally, the major components of the tested EOs were determined using Gas Chromatography‐Mass Spectrometry (GC‐MS). The MICs of T. daenensis and S. hortensis EOs against planktonic cells of the isolates were 0·0625 and 0·125 μl ml−1 respectively. The minimum bactericidal concentrations for both of the EOs was 0·125 μl ml−1. The MtP test showed a significant inhibitory effect of the EOs on the biofilm formation and disruption at sub‐MIC concentrations. These results were confirmed by SEM. Real‐time PCR revealed a significant down‐regulation of hld gene following treatment with MIC/2 concentration of S. hortensis EO. GC‐MS analysis showed that carvacrol, terpinene and thymol were the major components of the applied EOs.
Conclusions
As selected EOs did not show significant cytotoxic effects even up to tenfold of MIC concentration, the applied EOs seem to be good candidates for preventing of biofilm formation of Staph. aureus cells.
Significance and Impact of the Study
The present study introduced T. daenensis and S. hortensis EOs as new antibiofilm, and S. hortensis EO as anti‐QS herbal agents with natural origin against Staph. aureus.
Absorption of liquid or vapor water in paper designed for conversion processes is a critical phenomenon. In particular, the dimensional stability of the paper as the water content changes is crucial ...for the success of all the conversion processes, including copying and printing. Appropriate chemical treatments of the fibers can limit the phenomena of water absorption, allowing a better workability of the paper substrates. In the present study, moisture absorption tests were conducted under isothermal conditions on untreated papers and treated by coatings with silane, organo-siloxane and silicone agents, as well as with polyelectrolytes using layer-by-layer techniques. The treated and untreated papers were tested by changing the relative humidity between 0 and 80% relative humidity. The Guggenheim–Anderson–de Boer model was used to study moisture absorption isotherms, showing the increase in the dimensional stability of the papers after the chemical treatments of the fibers.
•Vibration of thick and FG circular plate with various boundary conditions is investigated.•Vibration of thick and FG circular plate in contact with fluid is investigated.•Vibration of circular plate ...in contact with fluid is investigated analytically.
This study investigates free vibration of a thick FG circular plate in contact with an inviscid, and incompressible fluid. Analysis of plate is based on First-order Shear Deformation Reissner–Mindlin Theory (FSDT) with consideration of rotational inertial effects and transverse shear stresses. Potential theory together Bernouli's equation are utilized to obtain the fluid pressure on the free surface of the plate. The governing equation of the oscillatory behavior of the fluid is obtained by solving Laplace equation and satisfying its boundary conditions. The natural frequencies and mode shapes of the plate are determined using Chebyshev polynomials. The effects of the geometrical parameters such as plate thickness to its radius ratio, boundary conditions, fluid density, volume fraction index, and height of the fluid on natural frequencies and mode shapes are investigated. Comparison of analytically outcome of this study is made with similar publications in the literature.
Repeat contrast-enhanced MR imaging exposes patients with relapsing-remitting MS to frequent administration of gadolinium-based contrast agents. We aimed to investigate the potential metabolite and ...neurochemical alterations of visible gadolinium deposition on unenhanced T1WI in the dentate nucleus using MRS.
This prospective study was conducted in a referral university hospital from January 2020 to July 2021. The inclusion criteria for case and control groups were as follows: 1) case: patients with relapsing-remitting MS, visible gadolinium deposition in the dentate nucleus (ribbon sign), >5 contrast-enhanced MR images obtained; 2) control 1: patients with relapsing-remitting MS without visible gadolinium deposition in the dentate nucleus, >5 contrast-enhanced MR images obtained; 3) control 2: patients with relapsing-remitting MS without visible gadolinium deposition in the dentate nucleus, <5 contrast-enhanced-MR images obtained; and 4) control 3: adult healthy individuals, with no contrast-enhanced MR imaging. Dentate nucleus and pontine single-voxel 12 × 12 × 12 MRS were analyzed using short TEs.
Forty participants (10 per group; 27 67.5% female; mean age, 35.6 SD, 9.6 years) were enrolled. We did not detect any significant alteration in the levels of NAA and choline between the studied groups. The mean concentrations of mIns were 2.7 (SD, 0.73) (case), 1.5 (SD, 0.8) (control 1), 2.4 (SD, 1.2) (control 2), and 1.7 (SD, 1.2) (control 3) (
= .04). The mean concentration of Cr and mIns (
= .04) and the relative metabolic concentration (dentate nucleus/pons) of lipid 1.3/Cr (
= .04) were significantly higher in the case-group than in healthy individuals (controls 1-3). Further analyses compared the case group with cumulative control 1 and 2 groups and showed a significant increase in lactate (
= .02), lactate/Cr (
= .04), and Cr (dentate nucleus/pons) (
= .03) in the case group.
Although elevated concentrations of Cr, lactate, mIns, and lipid in the dentate nucleus of the case group indicate a metabolic disturbance, NAA and choline levels were normal, implying no definite neuronal damage.
Tracking damaged roads and damage level assessment after earthquake is vital in finding optimal paths and conducting rescue missions. In this study, a new approach is proposed for the semi-automatic ...detection and assessment of damaged roads in urban areas using pre-event vector map and both pre and post-earthquake QuickBird images. In this research, damage is defined as debris of damaged buildings, presence of parked cars and collapsed limbs of trees on the road surface. Various texture and spectral features are considered and a genetic algorithm is used to find the optimal features. Subsequently, a support vector machine classification is applied to the optimal features to detect damages. The proposed method was tested on QuickBird pan-sharpened images from the Bam earthquake and the results indicate that an overall accuracy of 93% and a kappa coefficient of 0.91 were achieved for the damage detection step. Finally, an appropriate fuzzy inference system (FIS) and also an “Adaptive Neuro-Fuzzy Inference System” are proposed for the road damage level assessment. These results show that ANFIS has achieved overall accuracy of 94% in comparison with 88% of FIS. The obtained results indicate the efficiency and accuracy of the Neuro-Fuzzy systems for road damage assessment.
Background: Population aging leads to change of population structure and increase care needs. Lack of proper planning in this field will lead to occur increasing problems. In this paper, the review ...of the elderly care plans at various levels in some European and Asian countries, comparing these countries with Iran with the goal of using their experiences to enhance elderly plans have been done. Methods: This research was a review study of library documents and resources and systematic search. Data were collected using the resources, databases, scientific databases and websites of the Ministry of Health and Welfare of the studied countries. Results: Based on this research in the studied countries, the care services of the elderly is based on the important principle of coordination between different organs of the country, followed by the creation of LTC insurance and provision of health and social services for the elderly and mainly the type of home care. In Iran country, providing appropriate services and cares for the elderly with existing plans and policies is not possible and the need to provide appropriate service packages based on the different systems of successful countries and applying the experiences of these countries is essential. Conclusion: Given the current status of the Iranian elderly population in terms of policies and plans and the types and methods of providing services, quality, access and financial resources allocated to this age group, compared to the studied countries, there is a well and integrated plan is essential.