Optical characteristics of aluminum surface are vital for several applications and high reflectivity is required for applications of solar devices and optical microscopes. Electrochemical polishing (EP) was used for enhancement of leveling of the surface and elimination of nano/micro asperities, cavities and scratches. Electrolytic solution was prepared using mixture H3PO4, H2SO4 and H2O, with concentrations 55%, 14%, 31%, respectively. Ethylene glycol (EG) was added with different concentration 10, 20, 30 and 40 ml/l. After EP process, the samples washed well and dried at 110 °C. Then, the surface was investigated by SEM, AFM to evaluate the roughness of the surface. Gloss value and reflectance of the surface were obviously increased after EP treatment. Hardness and thickness of the surface were measured after EP treatment, where hardness was increased from 49 to 53 Brennel HB and thickness was increased from 1 to 3 µm after EP with addition of 20ml EG/l. Addition of 10ml EG/l showed the increase of corrosion resistance of Al surface to 36.707 KO and decrease of corrosion rate to 0.01890 mm/year after EP more than other concentrations.

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Carbon nanotube powder is being used extensively as reinforcement with many of the alloys currently. Specifically, with aluminum 7075 alloy, the properties observed to be better with respect to mechanical behaviour. In the current work the multiwalled carbon nanotube in the powder form was reinforced in aluminum 7075 matrix in stir casting method. The specimens obtained during the process are tested for the microstructure and mechanical characters. Investigation of microstructure under scanning electron microscope images confirmed the extent of bonding between the matrix and the reinforcement. The chemical composition of aluminium and the CNT powder were analysed using XRD procedure. The casted structures were machined to get the samples for mechanical tests. From the experimental results it was found that 1.25% of CNT reinforcement with the matrix improved the wear resistance of the composite sample produced. The specimens were prepared for the different weight percentage like 0%, 0.5%, 1% and 1.25% CNT by weight. The machined samples were tested for wear behaviour under the ASTM G99 standard and found that addition of CNT as reinforcement with the aluminium material will have enhanced resistance for abrasive wear principle. Thus the aluminium7075 mixed with the graphene based reinforcement like carbon nanotubes possess improved characters.

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The thermodynamic characteristics of combustion processes of a gas-generating composition based on ammonium perchlorate have been investigated. Polyethylene was chosen as a fuel, the choice in favor of this component is due to the fact that ammonium perchlorate readily interacts with polyethylene, and this fuel contributes to the rapid decomposition of ammonium perchlorate. The optimal composition of the mixture was found. It has been established that the highest efficiency and specific gas production are observed in the area of stoichiometric ratio of the initial components of gas generator compositions. The influence of the oxidizing agent ammonium perchlorate on the energy release of composite energetic materials, the thermal decomposition of ammonium perchlorate and ammonium perchlorate with polyethylene was studied by thermogravimetry and differential scanning calorimetry. In research for simultaneous thermal analysis of the ammonium perchlorate samples and the mixture of ammonium perchlorate with polyethylene (the portion of mixture was 8.6 mg, pure ammonium perchlorate was 10 mg, and the heating rate was 10°C / min.) was found that at temperatures around 514 K, an endothermic peak is observed corresponding to a polymorphic transition in the crystal structure of ammonium perchlorate, in both cases the peaks coincide. At a temperature of about 645.3 K, an exothermic peak can be observed, at which the oxidation of polyethylene occurs with a large release of energy. The peak at 702.2 K corresponds to the decomposition of ammonium perchlorate. The developed gas generator composition based on ammonium perchlorate can be used for open pit mining for splitting block stone in a gentle mode or breaking hard mineral rocks. This composition is safe from an environmental point of view, there are no toxic gases such as carbon monoxide and nitrogen oxides in the products.

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The goal of this research was to apply the characteristics of a second-order chemical reaction to a constant flow of MHD Jeffrey fluid through an electrically conducting stratified porous media across an exponentially stretched sheet. The BVP4c approach and the sequential application of the associated similarity variables yield the PDE numerical solution that controls flow. The charts show exhaustively the results of impartial effects on energy, temperature, and liquid fixation. The coefficient of rubbing, pace of hotness move, and mass exchange coefficients are totally portrayed and measured. A benchmark comparison benchmark is used to assess the veracity of the generated findings.

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The article describes the process of using soft-beam microfocus radiography for processing hybrid seeds of black currant in order to determine their qualitative characteristics. The studies were carried out using the PRDU-02 X-ray unit. For a more thorough analysis of small seeds, an X-ray microscope RM-01 was used. Soft-beam microfocus radiography is a gentle procedure for seeds, since it does not destroy their structure, and they fully retain their viability and are suitable for further use. It was found that even visually completely developed seeds have internal hidden defects, such as seed rotting, detachment of the shell from the cotyledons and underdevelopment. In general, the viability of seeds of different black currant varieties was at a high level and amounted to 85.7-91.8% of the total number of seeds studied. The largest number of completely developed seeds was revealed for the Il’yaMuromets variety - 91.8%, the smallest for the Binar, Peterburzhenka and Yadryonaya varieties - 85.7%. Microfocus radiography of black currant seeds showed that their viability was within the same limits as revealed by germinating them in laboratory conditions. Thus, the method of soft-beam microfocus radiography in determining the quality of hybrid seeds of black currant can be successfully used in the breeding process.

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In the view of obtaining a small-scale palm oil mill in rural areas with probably no electrical energy, the major bottleneck in some small-scale palm oil processing industries is the stripping (separation) of palm fruits from bunches. Therefore, it is very important to have an efficient small threshing machine. This paper depict the design of a palm bunch threshing machine which requires less human effort and very efficient. We selected Functional analysis tools (to express our need, show the relationship between our machine and its environment, and to express the logical relationship between the functions of the machine), geometric dimensioning to determine the various sizes of each component of our threshing machine and CAD software in 3D computer modelling and simulation of our palm bunch threshing machine. At end we obtained a design plan of an efficient threshing which requires less human effort and adapted to the rural environment.

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The COVID19 pandemic has had a significant impact on people's social lives. Due to this pandemic, almost every office, institution, organization in the world suffered a great deal from being practically closed. The World Health Organization (W.H.O) recommended everyone wear a mask whenever they step outside or in a public place. Therefore, it is mandatory to cover your face with a mask at public places, social gatherings, etc. Facemask detection has recently become one of the most important tasks to help society. The advancement of technology has proven that deep learning has shown its effectiveness in recognition and classification through image processing. There are many face detection models created by using several algorithms and techniques. Find whether a person has put on a mask properly or not and identify that person who didn’t put on a mask properly employing their age and gender. The combination of the face mask detection module and age & gender detection module is used. In our paper, the Haar cascade classifier was implemented to detect faces from the input images in the face mask recognition module. We train this module using CNN. We can recognize faces in this model using the Voila Jones technique and Haar-like features. The face detection module and age & gender detection module is trained by using a Convolutional neural network. A model trained by Tal Hassner and Gil Levi is used to implement Age and Gender detection; an alert sound will be a part of the outcome if the person is not wearing a mask properly. For the facemask detection module, the dataset is taken from Kaggle; images of people wearing masks and not wearing masks are gathered from different sources and formed into a dataset to train the model. In this paper, we used the Adience dataset to train age & gender detection and a dataset from Kaggle containing pictures of people’s faces with and without a mask. The model attains an accuracy of 93.42 %for face mask detection and an accuracy of 91.23% for Age and Gender detection.

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In this work, the effect of self-absorption on the lamps' luminous flux measurements at the NIS-Egypt integrating sphere facility has been studied. With integrating sphere photometry comes errors from self-absorption. Industry standards recommend applying absorption correction techniques for situations where the physical configuration and characteristics of the lamp or LED under test differ from the reference lamp. Self-absorption correction is critical since the physical size and shape of SSL products and lamps under test are typically very different from the reference lamp size and shape. In our study, different groups of lamps under test are used to determine its luminous flux as well as the self-absorption factor; High-Pressure Sodium (HPS), High-Pressure Mercury (HPM), Metal Halide (MH), Double-Ended Halogen (DE), Compact (C1,C2,C3) and LED (W1,W2,W3). Results show that the self-absorption factor has a considerable effect that can reach up to 7% on the measurements of total luminous flux such as in (DE) lamps. This effect must be considered and added to the measured luminous flux as a correction. Unless the test lamps are the same type as the standard lamps, the self-absorption should be measured and corrected.

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The present study proposes and explores a food chain model to study about the dynamical behavior of two preys and a predator ecosystem where the preys having competitive interaction among themselves. A Holling type-II functional response has been adopted for first prey and a predator of the proposed model. The boundedness, stability, existence condition of equilibrium of the model is investigated both from analytical and numerical point of view. Hopf bifurcation analysis is also discussed at the positive equilibrium point and a global property of dynamical system is one of the parts of the study. Here, the presented work also utilized to calculate the instability of the population throughout the co-existence’s state of steady because of the white noise. At last, the study is hold up by performing the numerical illustrations.

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In this paper, URDE® software is introduced for the unpaved road distress evaluation using the VIZIRET method. This software is written in Hypertext Preprocessor and Php programming language, which allows multiplatform running, and since this is a Web application, it works on all operating systems. URDE® software helps estimate the viability index, road condition, and possible rehabilitation method on 100 m. URDE® is suitable for reducing the rehabilitation method’s decision-times in situ, which is essential for government public dependencies who admin the unpaved roads. Besides, this software allows interaction with software DACE® and SDDRoads® to design unpaved roads and side drainage design for roads; the above, in case of count on the answer of reloading or rebuilding of roads. Finally, URDE® was demonstrated to be an interesting application for calculation road distress evaluation anywhere in the world with similar or equal criteria to the VIZIRET method.

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Basically many of researchers and guide lines were defined as Self-compacting concrete is a highly flowable and it can totally fill the form work under the action its own weight, even with a high congestion of steel reinforcement, it can compact totally without segregation and bleeding. Since from earlier 1983, durability of concrete structures was major problem of interest in Japan, for making concrete durable structures, cementitious materials replaced partly with pozzolanic materials like GGBS and SF. This study aims to focus on the possibility of using industrial by-products like Ground Granulated Blast Furnace Slag (GGBS) and Silica fume in preparation of SCC. Eight numbers of SCC mixtures and one number of control concrete mix were prepared for this investigation. The quantity of the cementitious materials and water cementitious ratio was maintained constant i.e. cementitious materials (500 kg/m3), while the water cementitious ratio ranged from 0.35 to 040. The self-compacted concrete mix has prepared with a cement replacement of 30%, 50% and 70% by GGBS and Silica fume (by 2% weight of GGBS) in addition Auromix 300 plus is used as Chemical admixture to achieve the required flow ability, Compressive tests and flexural Tests were done on hardened properties and T50, Slump flow, L-Box, V-Box, and U-Box tests were done on fresh properties of self compacted concretes. The test results show that an economical self-compacting concrete could be successfully developed by incorporating high-volumes of GGBS, and also it proves that making of self-compacting concrete more affordable and low cost for the construction market by replacing high volumes of Portland cement by GGBS. The Cube and beam specimens were casted and cured in to NaCl solution (3.5% by weight of water) after normal 28days curing. Durable Studies have been carried out, such as Chloride penetration by chemical analysis, Corrosion of reinforcement by RPS system and Micro analysis of SCC by XRD,EDX and SEM tests for exposure ages of 28, 56, 84 and 98days.

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This work presents an application’s design based on Matlab for the relative biomass measurement through the NDVI (Normalized Differential Vegetation Index) using a drone or unmanned aircraft. This application allows farmers to view the crops’ topsoil state in real-time to determine corrective or improvement actions. The NDVI calculation response is evaluated through the percentage referenced in the number of pixels with specific image characteristics, which must be a value greater than or equal to 0.2 of NDVI. The results are compared with commercial software. As a result, it’s shown the pixel saturation correction stage through the reflectance correction system allows to obtain 10% of pixels lower than the NDVI threshold, at the same time improves the vegetation cover state visualization since by eliminating in this stage, several areas of the culture show overexposure (low color contrast) in the NDVI values.

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