In this work, modelling and simulation of a vacuum swing adsorption unit has been carried out using Aspen Adsorption simulator. The major chemical components involved in the development of the model were carbon dioxide and nitrogen. Peng-Robinson equation of state was chosen as the fluid package. The model of the system was developed by inserting the necessary blocks and streams into the flowsheet, connecting the blocks with the streams, inputting the stream parameters and specifying the kinetic models as well as the mass transfer coefficients required for the simulation. In the simulation environment,0.09-0.1kmol/s of dry flue gas was passed through a 2-bed adsorption system in a six-step cycle and the adsorbent used was Acticarb GC1200, which was activated carbon derived from coconut shells. The adsorbent beds used were designed to have values that would give maximum efficiency of the system. The model developed for the system was run for 10 cycles. The results obtained showed that the unit could be operated with two adsorber beds each having a diameter of 1.76479 m and a height of 3.53568 m with an isentropic vacuum pump. It was also discovered that the adsorbent employed for the simulation was able to capture CO2 from flue gas under the established performance criteria. The results obtained were found to compare well with those of other researches. It is recommended that the process should be subjected to optimisation for the purpose of improvement in the design and operation.

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Mobility robot is mostly used by blind and partially sighted people as a mode of transport, leading to more people becoming vulnerable to invisible harm caused by vibration propagated along with the mobility robot structure. Random vibration from different sources propagated along with mobility robot to members of rider body, commonly known as Whole-body Vibration (WBV). Riders commonly experience WBV due to the propagation of vigorous vibration along with the mobility robot footrest. Therefore, vibration analysis is conducted onto the footrest of mobility robot to study its dynamic characteristics corresponding to the excitation frequency induced from the power train of mobility robot. Simulation analysis approach is selected as the method to conduct Finite Element Analysis (FEA). Computer-Aided Drawing (CAD) drafts of the footrest are prepared using CATIA and import the CAD footrest models to ANSYS Workbench to conduct FEA. Two set CAD drafts of footrests are prepared consist of the original and proposed footrest. As a result, it is found that increasing the mass of footrest can reduce the vibration level by more than 93% for X-axis, 70% for Y-axis and 90% for Z-axis. Furthermore, increasing the stiffness of footrest also increased the natural frequencies with the highest increment percentage in the second natural frequency of the proposed footrest, up to 70.12%. In a nutshell, with the increase of mass and designing an appropriate geometry of footrest able to reduce the vibration level significantly.

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At oil and gas production facilities and other industries, special transport and technological machines of foreign production are often used. One of the tasks of the technical department of organizations is to provide cars with spare parts and consumables. Many spare parts may not be manufactured in a particular country. In this regard, a rather long supply chain of spare parts with a large number of intermediate links is being formed. This increases the delivery time and the already high cost of spare parts. The article proposes a solution to the problems of long terms and cost of supplying spare parts by introducing additive manufacturing technologies for spare parts in organizations that manage the fleet of vehicles.

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The aim of this study is to highlights the importance to shift from the use of traditional fossil fuels to biodiesel as a clean energy source. A simulation study has been conducted using ASPEN HYSIS software for the biodiesel production form castor oil. The simulation was run and the properties of the produced biodiesel were highlighted. The optimum conditions resulted in 88 % conversion.

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The article presents the results of a numerical study examining load-bearing capacity for cross sectional elements of a bus (in particular side window struts\posts). The author offers the implementation of the finite-elemental method analysis of the stress-strain state, using the ANSYS application package for a bus window post when bent where chemical corrosion of the material was taken into consideration. The numerical study of the load-bearing was carried out for a console fixed rack during bending in the plane which is perpendicular to the axis of the bus, taking into account the geometric and physical nonlinearity of the material in combination with a decrease in the thickness of the structure due to the corrosion of the metal, and for a truncated post with force applied at an angle to the loading site under the same conditions. A series of computational experiments was provided for an integral rack with localised corrosion. The conditions and boundaries for the subsequent finite-element modeling of cross sectional elements of a bus were considered constant for the purpose of this article.

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The article discusses the processes of metrological support in the field of labor protection and safety at food industry enterprises, in terms of verification and repair of measuring instruments in operation and used to control hazardous and harmful production factors to create new methods and algorithms for solving problems of organizing and planning metrological support combining modern mathematical approaches and software tools into a single whole, taking into account the needs in metrological services of industrial enterprises.

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Neighborhood Pattern Sensitive Fault (NPSF) is the typical fault which occurs due to the coupling action among neighbouring cells in the memory. Other faults like stuck at faults, address decoder faults can be detected using March Algorithms, but Neighborhood pattern sensitive faults can’t be detected easily. So, there is a need for the improvisation of fault detection in memories for NPS Faults. This paper proposes a new approach for testing of passive NPSF (PNPSF) in memories. This approach comprises of a Hamiltonian and Gray sequences for non-optimized and optimized techniques used for PNPSF detection with Linear Cellular Automata (LCA) and Linear Feedback Shift Register (LFSR) as address generators. A 3-cell neighborhood approach is considered for the testing of PNPSF, which has one base cell and corresponding neighborhood left cell and right cell. The complete test setup using this approach will configure the PNPSF impact on base cell due to transitions in the corresponding neighborhood cells. The comparison of the timing and fault insertion analysis of all four PNPSF testing approaches are tabulated, also the optimized sequence gives better fault coverage than non-optimized Hamiltonian and Gray sequence. The proposed methods of PNPSF architecture for memory testing is synthesized and implemented using Xilinx 14.7.

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A conventional three phase gas protected substation comprises of every one of its segments encased in sulphur hexafluoride gas. The dielectric quality of SF6 is too high when contrasted with that of air and subsequently makes it electrically better than customary air protection. In any case, SF6 is thought to be a green house gas and subsequently its use is to be constrained. This can be accomplished by utilizing selective gases like Nitrogen (N2), Carbon dioxide (CO2). On the other hand , for better after effects of getting both high dielectric properties and decreasing green house impacts, blends of these gases alongside SF6 can be utilized for agreeable activity of GIS. The significant issue with the GIS is the presence of electric contaminants which for the most part begin from the inside parts of the enclosures. The movement of these metallic contaminants is to be limited to enhance the proficient activity of GIS. The present work manages investigation of the movement of generally experienced aluminium and copper metallic particle contaminants in the Gas insulated Substations. The blends of SF6+CO2, SF6+N2 and SF6+air have been utilized as options for unadulterated SF6 gas. The developments of metallic particles are investigated for various extents of gas mixtures and 550kV power frequency ac voltage, the details of which are discussed.

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The volume of raw materials in Kazakhstan is growing rapidly every year. The level of reliability of the use of technical systems in the chemical technology industry is directly related to increasing production efficiency, directly related to the reduction of production costs, for energy resources and repair work, etc. This work depends on the correct implementation of activities related to the technical condition of industrial equipment, i.e. the reliability of the installations and technical diagnostics.

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Nickel doped Fe3O4 nanoparticles were prepared using ball milling method by varying the different wt.% of nickel. The influence of nickel content on physical properties including structural, magnetic, morphological properties and elemental content of Fe3O4 nanopareticles were studied using X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM) and X-ray fluorescence (XRF) spectroscopy, respectively. XRD patterns of prepared samples were indexed to cubic structure and confirmed that undoped sample consists only Fe3O4 (magnetite) phase, while the nickel doped samples show two phases including Fe3O4 and nickel phase. Moreover, XRD peaks of nickel doped samples shift to slightly lower angles as compared to that of undoped sample resulting increase of crystallite size (29 to 32 nm). These results together with SEM measurements show that the size of the nanoparticles increases with increasing nickel content. Magnetic studies indicated that, in comparison to undoped sample, the saturation magnetization (Ms) of nickel doped samples increases with increasing nickel content. Comparison of elemental composition from raw material to undoped and nickel doped samples shows that the Fe and Ti content increase after being milled, while some impurities such as Al, Si, Ca and others decrease. Hence, based on the observed values of physical properties of the nickel doped Fe3O4 nanoparticles makes them applicable as an efficient material for wastewater remediation.

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The solution of the problems of the direct and inverse problem of the kinematics of the modules of intelligent electromechanical systems is considered. A description is given of the kinematic model of the system, as well as variants of solving optimization tasks for controlling trajectories of motion.

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Increased demand for technology-driven and automated infrastructure that can address critical issues like passenger safety and traffic congestion has led to an exciting research and application area - Vehicular Adhoc Network (VANET). VANET enables vehicles to talk among them and also with fixed roadside infrastructure to support a myriad of potential life changing applications. The excitement surrounding VANET is not due to their application support or potential benefits but also because of the challenges like scarce spectrum, varied QoS requirements, poor connectivity, security issues etc., Cognitive Radio (CR), a technology that ensures efficient spectrum usage can be employed in VANET to address spectrum scarcity issue. Though several spectrum sensing algorithms have already been proposed, there is a need for an effective algorithm that has a significant impact on various sensing parameters like accuracy, delay and efficiency. Our focus in this paper is to provide a machine learning based sensing algorithm for CR VANETs implemented at physical layer that maximizes the spectral efficiency.

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