Modeling the process of accumulation of kinetic energy in the elastic elements of a dynamic tillage working part and changing its constructive parameters is an urgent issue, since it allows to develop new efficient tillage working parts endowed with the property of dynamism. The aim of the research is to develop mathematical models of the process of accumulation of kinetic energy and changes in the constructive parameters of dynamic tillage working parts. The object of research is a dynamic arrow-shaped tillage working part with a capture width of 330 mm for surface tillage to a depth of 14 cm. The subject of research is the regularities of the process of accumulating kinetic energy in elastic elements and changes in the constructive parameters of a dynamic tillage working part. The research was carried out using methods of mathematical modeling based on the study of physical laws that occur during soil cultivation; experimental research on energy assessment of tillage working parts, analysis and generalization of experimental data. The scientific novelty of the paper is represented by mathematical models of the process of accumulating kinetic energy and changing constructive parameters of a dynamic tillage working part. Mathematical models and graphic interpretation of the dependences of the axial force on the elastic element, the traction resistance of the dynamic working part, the average value of the width of capture on the speed of movement of the dynamic working part are presented in this paper. In particular, it was found that under the specific conditions of experiments with an increase in the speed of operation from 1.94 to 3.61 m / s, the average value of the width of capture of a dynamic tillage working part decreases from 306.90 to 300.50 mm. At rest, the dynamic soil tillage implement has a working width of 330 mm. The meaning of the swath width of a dynamic tillage working body, depending on the characteristics of the soil and the speed of movement, fluctuates within certain limits set by design parameters and is a random value. The statistical standard error of the sample mean value of the traction resistance and the speed of movement of the dynamic working body, respectively, varied in the range of 0.094 - 0.0167 kN and 0.012 - 0.032 m/s.

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Leachate is the product of biodegradation process in the landfill, which possesses various disadvantages to the environment. It needs proper treatment to avoid those negative impacts of the leachate. On-site treatment of leachate using leachate recirculation is one of the alternative technologies to reduce the hazard. This study evaluated the application of leachate recirculation as an alternative method of leachate treatment in landfills. Experiments were performed in a laboratory using a total of 60 lysimeters, with 1 L in volume for 365 days. The waste was placed on the top of a gravel to avoid any blockage and percolate the leachate to the bottom of lysimeter. The lysimeter was divided into two groups, with 10 reactors each group arranged in series and conducted in triplicate. Leachate recirculation will be given to second reactor until tenth reactor, using high concentration of leachate for the first group and low concentration of leachate for the second. The recirculation of leachate in both treatment groups significantly increased the organic content in the waste. In the reactor group with low-concentration leachate, the increase in organic content was lower than in reactors with high-concentration leachate. It was found that leachate recirculation accelerates reductions in the BOD and COD concentrations of leachate, compared to reactors without leachate recirculation. This condition applied to both treatment groups. In general, reactors with leachate recirculation had higher BOD and COD removal efficiencies than those without.

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The influence of the metachronal beating of cilia, heat transfer phenomenon, oblique magnetic field, and Hall currents on blood flowing inside an isotropically stenosed elastic artery were investigated analytically. All physical parameters associated with blood flow properties were studied and discussed graphically for both ciliated-free isotropic artery and ciliated-tethered artery. The results obtained in this study showed that the velocity, the distribution of wall shear stress, and the resistance are higher for free isotropic artery model than that for tethered artery model. The distribution of wall shear stress increases with the cilia position increasing and it decreases by increasing the eccentricity of the elliptic path whereas the resistance impedance has inverse trend. Furthermore, the streamlines patterns illustrating the features of the ciliary motion have been plotted for various imbedded flow parameters.

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The basic criterion of performance in a production system is response time and variability of process parameters, and it is reasonable if all of these are at their lowest value to demonstrate the rapid rate at which an anomaly can be detected by the system and appropriate action taken. With lean automation technique in the sugar industry, process variability and real time control can be monitored. Also, to note is the consistency of the response times where sharp variations will imply erroneous system operation. This technology is achievable through the different levels of automations that sugar industries adopt. Thus, an analysis of the different levels of automation was carried out at different stages of pre-milling process of sugarcane to determine the optimum automation level for adaptive control in a case sugar company. It was found that level 4 of automation had a slow response to anomaly with the longest mean response time of 3.33 minutes compared to levels 5 and 6 which depicted a rapid response to anomaly with the shortest response time of 0.54 min. Also, conventional automation (LoA 4) resulted to an average temperature variability of 2.75 °C. While the SCADA (LoA 5) and DCS (LoA 6) showed no temperature variability in the three process stages. Thus, adopting levels 5 or 6 the process parameters are controlled and maintained at the optimum levels and provide a steadfast real time monitoring, control and maintenance of process parameters that will enhance quality production.

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Chlorophyll sustains plants as it is one of the vital components in the photosynthesis process. Chlorophyll content in the leaf indicates the health of the plants and it can be used as an indicator for fertilizer requirement, in particular for Nitrogen management, in the growing cycle of certain crops. Chlorophyll measurement is required for the growers to monitor and make decision for fertilization schedule. The measurement is also needed for plant scientists. Chlorophyll meters are used to measure the relative chlorophyll content index in the leaf either by chemical process, image processing, or spectroscopy technique. In general, chlorophyll meters are expensive. This work proposes a low-cost meter to measure the chlorophyll index by exploiting the newly-developed near-infrared spectrometer. The NIR spectrometer is an optical MEMS sensor having 6 channels spanning from 610nm to 860nm. The simple prototype was built by using the common Raspberry Pi to collect data from the spectrometer. Fifteen leaf samples from various tree types were measured and data were analyzed. The results were compared with the commercial hand-held device, the SPAD-502. An average error of 7.84% was obtained using the designed meter. Off-the-shelf components provide a fraction of the cost of the high-end meters for an acceptable chlorophyll content index reading.

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The report presents the results of research at the engineering design of a turbomachine combustion chamber running on supercritical carbon dioxide at an ambient pressure of 300 bar. The research method is a numerical simulation of turbulent-kinetic processes in the Ansys Fluent software package using the reduced methane combustion mechanism. Two key features characterize the combustion of methane in CO2 diluent. Firstly, combustion occurs with a significantly smaller excess of oxidizing agent than in the combustion chamber of traditional gas turbines. Secondly, the normal flame propagation velocity in CO2 at ultrahigh pressure is much lower than with N2 diluent. In order to ensure stable and complete burning of fuel, various ways to increase the real burning rate were reviewed - swirling the mixture of fuel and oxidizer, controlling the distribution of diluent over the volume of the combustion chamber, changing the main structural dimensions of the combustion chamber.

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Extracting text information from a web intelligence page is a difficult task as a great piece of the E-News substance is given assistance from the backend Content supervision method. Web content extraction is a vital innovation for empowering a variety of utilizations pointed toward accepting the network. While mechanized web harvesting has been concentrated widely, they regularly center around separating organized information that shows up multiple times on a solitary website page, similar to item indexes In this Work, we present a customized news internet searcher that centers around constructing a storehouse of reporting stories by relating proficient mining of content data from a network information sheet from shifted e-information entrances. Our approach characterizes text blocks utilizing a combination of visual and language autonomous highlights. The framework depends on the idea of the Document Object Model (DOM) hierarchy control for separating content and changing the site page configuration to prohibit unessential substance like advertisements and client remarks. We additionally utilize WordNet, a vocabulary of the English speech dependent on psycho bilingual person reads for coordinating the separated substance equivalent to heading of website page. TF-IDF (Term Frequency Inverse Document Frequency) is utilized to recognize the sheet block conveying data pertinent to the page's designation. Notwithstanding the pulling out of data, working to accumulate associated data from various web information documents & sum up the assembled data dependent on client inclinations which have additionally incorporated. Furthermore, a pipeline is devised to naturally name data points through bunching where each group is scored dependent on its importance to the site page depiction extricated from the Meta labels, and data-points in the best group are chosen as certain preparation models.

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The development of the Digital Twin of an exoskeleton for upper limb rehabilitation task for hemiplegic patients, and its Virtual Commissioning prior to its manufacture is presented in this work. In these context biomechanical and clinical design criteria are integrated into Digital Twin concept. The power actuators, the development of 4 freedoms degree's mechanisms for shoulder and elbow flexion/extension, external and internal rotation and abduction of the upper limb, and prone/supination of wrist, the control system and user interface as well as its integration with the mechanical system is carried out. The mechatronic concept design is done using NX MCD software. Automation takes place in the TIA Portal software. A PLC which can be virtually simulated with the use of PLCSIM Advanced software and a Human-Machine Interface (HMI) for the control of the exoskeleton are included in the hardware configuration. The Real Commissioning of the designed prototype has been successful and its operation has been validated in pilot tests carried out at the Santiago de Cuba Surgical Clinical Hospital in hemiplegic patients with painful shoulder syndrome.

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The objective of this study to evaluate the performance efficiency of wastewater treatment plant in Aqaba governorate in Jordan. One hundred twenty samples of wastewater were collected from both influent and effluent of Aqaba Wastewater Treatment Plant (AWWTP). Samples are analyzed for biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS) to evaluate efficiency of (AWWTP). BOD was nearly decreased to extremely low level and the decrease rate is 98.9 % while COD 97.3 % and TSS is 98.7 %. These rates of decrease of BOD, COD and TSS clarified the satisfying in general effectiveness of the plant. Regression equations for BOD, COD and TSS removal percentages were proposed which can be utilized to evaluate rapid effluent assessment after the treatment processes or optimal process control to improve the performance of (WWTP). The average Biodegradability index (BI) was found to be 0.46. The percentage removal of influent BOD, influent COD and influent TSS were found with high determination coefficient (R2) 0.97, 0.97 and 0.89 respectively.

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An educational computer program was developed for the matrix analysis of plane frames aimed at engineering students. Unlike commercial programs, the application has a plus since it is designed to assist in the step-by-step calculation of matrix analysis of plane frames subject to point loads and uniformly distributed loads perpendicular to the elements. This topic is fundamental in the teaching of the structural analysis course in engineering careers. The conceptual and mathematical model, the pseudo code of the computational model in FORTRAN, the verification of the application with SAP2000 using a classic problem from the literature are shown, concluding that the tool developed is an alternative for assisting the teaching-learning process in the classroom and for the autonomous work of engineering students in studying of the plane-frame matrix analysis method. This educational program is part of an educational-toolkit project developing to improve students’ autonomous work and teacher-student communication [1].

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Improving the physical and mechanical properties of castings from alloyed steels and alloys is achieved in various ways, such as: increasing the purity of metal by non-metallic inclusions, creating favorable crystallization conditions that affect the formation of macro and microstructure, reducing the development of liquation processes, etc. Currently, high-energy processes, including electroslag technologies, are widely used. Application of this technology makes it possible to significantly improve quality of steels due to reduction of content of harmful impurities as a result of refining action of slag in process of electrode remelting, besides, it performs protective function in process of metal remelting and pouring into mold. After overflowing the metal from the crucible into the shape, the flux accumulates in the upper part of the casting and acts as a thermal extension, which has a favorable effect on the crystallization process. The purpose of this work is to study the physical and chemical processes that occur during the interaction of harmful impurities - sulfur, phosphorus and oxygen, with components that are part of slag and with rare earth metals, which are modifiers, as well as to study the effect of the amount, morphology and distribution of non-metallic inclusions on the mechanical properties of castings from steel H11 when using electric slag coke casting. In the course of the work, based on the calculated reactions, the influence of Ca and Al on the desulfurization, dephosphorization and deoxidation of steel, as well as the effect of rare earth metals on the formation of sulfide, oxysulfide and phosphide compounds, which are prone to the formation of large conglomerates, which contributed to their accelerated surfacing in the upper part of the casting and, as a result, to a decrease in the total number of non-metallic inclusions in steel. The number of non-metallic inclusions in the modified steel decreases by more than 4 times compared to the non-modified steel, and the toughness increases from 0,20 to 0,32–0,30 MDzh/m2.

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This work is aimed at studying the colour rendering parameter in telecommunication paths. The authors present an analysis of the existing problem, which may occur when introducing machine vision and artificial intelligence training systems. An important feature that is discussed in this paper is the influence of the light source and the parameters of the final equipment. The authors also discuss a comparative analysis of the influence of various light sources, and those differing from the reference spectral characteristics of the camera. Conclusions are made about the possibility of eliminating colour rendering errors in telecommunication paths. Recommendations are presented to show how to reduce the impact on colour rendering quality.

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