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Hybrid Deep VGG-NET Convolutional Classifier for Video Smoke Detection
No full textReal-time wild smoke detection utilizing machine based identification method is not produced proper accuracy, and it is not suitable for accurate prediction. However, various video smoke detection approaches involve minimum lighting, and it is required for the cameras to identify the existence of smoke particles in a scene. To overcome such challenges, our proposed work introduces a novel concept like deep VGG-Net Convolutional Neural Network (CNN) for the classification of smoke particles. This Deep Feature Synthesis algorithm automatically generated the characteristics for relational datasets. Also hybrid ABC optimization rectifies the problem related to the slow convergence since complexity is reduced. The proposed real-time algorithm uses some pre-processing for the image enhancement and next to the image enhancement processing; foreground and background regions are separated with Otsu thresholding. Here, to regulate the linear combination of foreground and background components alpha channel is applied to the image components. Here, Farneback optical flow evaluation technique diminishes the false finding rate and finally smoke particles are classified with the VGG-Net CNN classifier. In the end, the investigational outcome shows better statistical stability and performance regarding classification accuracy. The algorithm has better smoke detection performance among various video scenes
Evaluation of Antioxidants, Total Phenolics and Antimicrobial Activities of Ethyl Acetate Extracts From Fungi Grown on Rice Straw
No full textRice straw (RS) collected from Egyptian agricultural environment (Al-Masied village-Alsharqia Governorate-Egypt) was used as substrate for three fungal isolates namely: 4b, 1Asp, Pleurotus ostreatus NRRL 3501 and mixed culture of (4b, 1Asp). Isolates number 4b and 1Asp were identified using the molecular technique (18S rRNA). Isolate 4b and 1Asp, were identified as Trichoderma saturnisporum MN1-EGY and Aspergillus niger MN2-EGY, respectively. Trichoderma saturnisporum MN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal extracts. Total phenolic, antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these fungi. The antioxidant scavenging concentration(SC50) values of the tested samples were 88.84, 91.45, 94.65 and 100.0μg/ml, respectively for Pleurotus sp., Aspergiluus niger, Aspergiluus niger + Trichoderma sp., and Trichoderma sp., after 15 days incubation, compared to ascorbic acid as positive control with SC50 value equal to 8.0 μg/ml. Total phenolic contents (TPCs) were maximum in Pleurotus sp. extract and found to be the most polyphenolic enriched sample (380.64 mg GAE/g dry extract) compared to extracts of Aspergiluusniger, Aspergiluus niger + Trichoderma sp., and Trichoderma sp. (261.89, 198.52, and 119.80 mg GAE/g dry extract), respectively. The GC-MS analysis has been also performed for the promising extracts
Studies on Epoxidised Castor Oil as Co-Plasticizer with Epoxidised Soyabean Oil for PVC Processing
No full textAn acidic cation exchange resin has been used to prepare epoxidised castor oil (ECO) which was used as a co-plasticizer with epoxidised soyabean oil (ESBO) for processing polyvinyl chloride (PVC). The structure of ECO was confirmed and its physico chemical properties were evaluated. PVC/ (ESBO&ECO) blends were prepared by melt mixing and compression molded into sheets. The specimens were evaluated for tensile properties, impact strength and hardness. While the tensile strength did not vary much, the elongation reduced with the replacement of ESBO with ECO. Dynamic mechanical studies revealed that the glass transition temperature increased with incorporation of ECO, however, the storage modulus was not altered much. Replacing 20% of ESBO with ECO resulted in blends with desired thermal and mechanical properties without affecting the processability of PVC
The Effect of the Process on Mechanical Properties of Polylactic Acid-Date Palm Leaf Fibers Composite Films Produced By Extrusion Blowing
No full textBiocomposite films prepared with melt compounding and film blowing have become a new trend in plastic research to deliver more eco-friendly packages. Polylactic acid (PLA) was melt compounded with minimally processed date palm leaf fiber (DPLF) and converted into films by blown film extrusion. The compounding was done in order to enhance the film mechanical properties in one hand, and to decrease the film production cost in the other hand. In this present study, a reference PLA film and films with 1%, 2%, and 5% of DPLF (weight %) were produced with different process parameters. The spatial variations in films thickness and lay flat width indicate that the addition of DPLF up to 2% enhances the bubble stability for the tested process parameters. However, the composite with 5% DPLF shows nearly the same processability window as the neat PLA. The structural and mechanical characterizations of films suggest a reinforcing effect of the PLA matrix up to 2% of fiber (with an optimum at 1%). Larger DPLF loading leads to depressed and more anisotropic mechanical properties, related to an increased density of defects at the fiber-PLA fragile interface and to a DPLF-induced enhanced PLA thermal degradation and amorphous phase orientation
Zinc Oxide Nano Particles Integrated Kenaf/Unsaturated Polyester BioComposite
No full textIncreasing need for materials with special features have brought various new inventions, one of the most promising hope for new material with special features and functionalities is composites materials. Thus, this study report an integration of zinc nanoparticles into kenaf/polyester polymer composite to introduce new behavior to the composite. The composite behaviors were compared for mechanical, thermal, moisture absorption and biodegradability properties. Prepared Zinc Oxide nanoparticles entrenched in the kenaf/polyestaer composites net structure through chemical bonds between kenaf/ZnO/polyester resin, existence of ZnO significantly influence the mechanical and thermals properties of composites. Thermal analysis based on (TGA) response revealed the integration of ZnO nanoparticles improved the thermal stability when thermal decomposition temperature beyond 3650 C. The thermal cracking decreased with present of ZnO and increase with kenaf content (layers). The modulus, Tensile strength, break at elongation, flexural modulus, flexural strength and impact strength of the composites with higher content kenaf/ZnO nanoparticle are 560 MPa, 58MPa, 1.8%, 1300 PMa, 68 MPa and 31 MPa, respectively. Thus, addition of kenaf layers and ZnO results in larger mechanical properties enhancement, the results of the contact angle show improvement in wetting of the fibres with addition of ZnO nanoparticles
Mechanical Properties of Polypropylene Composites Reinforced with Macadamia Nutshell Fibers
No full textThe use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries, for its low cost, mechanical properties, biodegradability and lightness. However, the hydrophilic nature of the fiber makes polymer compatibility difficult. Fiber surface treatments can be used to enhance the fiber/matrix interface. In the present work, polypropylene (PP) composites reinforced with fibers from macadamia nutshell were obtained and characterized. Macadamia nutshell fibers were treated by an alkaline treatment with sodium hydroxide (NaOH 4%) to improve adhesion between fibers and matrix. Fibers were characterized by techniques of Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The PP was mixed with the macadamia fibers (treated and untreated), in proportions of 5 and 10% (wt/wt) using a thermokinetic mixer. Furthermore tensile, flexural and impact specimens (Pure PP and composites) were prepared by an injection molding process and tested for evaluation of mechanical properties. The results showed that the insertion of treated fibers in the PP matrix increased the stiffness of the composites. However, the composites reinforced with untreated fibers presented higher impact energy absorption when compared to composites reinforced with treated fibers
Ensemble Recurrent Neural Network-Based Residual Useful Life Prognostics of Aircraft Engines
No full textResidual useful life (RUL) prediction is a key issue for improving efficiency of aircraft engines and reducing their maintenance cost. Owing to various failure mechanism and operating environment, the application of classical models in RUL prediction of aircraft engines is fairly difficult. In this study, a novel RUL prognostics method based on using ensemble recurrent neural network to process massive sensor data is proposed. First of all, sensor data obtained from the aircraft engines are preprocessed to eliminate singular values, reduce random fluctuation and preserve degradation trend of the raw sensor data. Secondly, three kinds of recurrent neural networks (RNN), including ordinary RNN, long short-term memory (LSTM), and gated recurrent unit (GRU), are individually constructed. Thirdly, ensemble learning mechanism is designed to merge the above RNNs for producing a more accurate RUL prediction. The effectiveness of the proposed method is validated using two characteristically different turbofan engine datasets. Experimental results show a competitive performance of the proposed method in comparison with typical methods reported in literatures
LiToTac: An Interactive-Interface Software for Finite Element Analysis of Multiple Contact Dynamics
No full textIn order to investigate the mechanical behavior of systems with complex architecture and a large number of contacting bodies, a finite element software, named LiToTac, has been developed by using the object-oriented programming technique. This software, with an interactive graphical user interface, is able to handle highly non-linear problems including multiple contacts and large deformation. More importantly, the contact detection based on a hybrid three-stages methodology can be performed automatically, which is more efficient than the common strategies of pre-defining contact zones in commercial FEM software like ANSYS, ABAQUS, etc. In addition, the contact solver in LiToTac is portable between dynamic and quasi-static codes and can accurately solve contact coupled with friction in a reduced system. Several numerical examples are carried out to illustrate the functionality and capacity of the software package
Solving the Nonlinear Variable Order Fractional Differential Equations by Using Euler Wavelets
No full textAn Euler wavelets method is proposed to solve a class of nonlinear variable order fractional differential equations in this paper. The properties of Euler wavelets and their operational matrix together with a family of piecewise functions are first presented. Then they are utilized to reduce the problem to the solution of a nonlinear system of algebraic equations. And the convergence of the Euler wavelets basis is given. The method is computationally attractive and some numerical examples are provided to illustrate its high accuracy
Gene expression profile of Sox1, Sox2, p53, Bax and Nestin in neural stem cells and adult mouse brain tissues
No full textHistone deacetylation is a key modulator involved in cell proliferation, apoptosis, and mRNA transcription.
However, the effects of histone deacetylation on C17.2 neural stem cells (NSCs) remain unclear. Here, the histone
deacetylase inhibitors nicotinamide and trichostatin A (TSA) were used to determine the role of histone deacetylation
on gene transcription in NSCs. The results showed that the mRNA expression of p53, Sox1, Sox2, and Bax were
significantly higher in E14.5 NSCs than in C17.2 NSCs. Nestin, a marker gene of neuronal differentiation, did not differ
significantly between E14.5 NSCs and C17.2 NSCs. The transcription levels of p53 and Nestin were significantly higher
in C17.2 NSCs than in differentiated brain tissues, and the expression of Bax, Sox1, and Sox2 was higher in the olfactory
bulb than in other brain tissues. Nicotinamide and TSA treatment decreased the transcription of Sox2, p53, Nestin, and
Bax in C17.2 NSCs, although the difference was statistically significant only for Sox2 and Nestin, Sox1 transcription
was not detected. These results demonstrated that mRNA expression profiles differ between C17.2 NSCs, E14.5 NSCs,
and adult mouse brain tissues, and HDAC inhibitors regulate gene expression by modulating histone acetylation