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Sheet metal working processes find extensive applications in industries such as automobile and aerospace. However, the sharp edges of sheet metal pose a safety hazard to workers, potentially leading to injuries. In response to this concern, we have conceived and developed an automatic sheet metal cutting machine. Feeding mechanism is one of the important part of sheet metal shearing machine. In this paper, recent research papers are reviewed. This papers also reports recent development in feeding mechanism and its role for productivity improvement. Also, proposed innovative feeding mechanism represents a pivotal advancement in the field of mechanical workshops, aligning with industry demands for increased productivity and safety in sheet metal processing. Paper throws lights on benefits of automation into the sheet metal cutting process, which a significantly reduces in labour costs while ensuring precise and efficient cutting operations. Paper also focuses the various parameter such as cutting speed, material properties.

The interference of metal working surfaces on the electric field can lead to performance variations between the flush mounting and non-flush mounting of capacitive proximity sensors in industrial applications. Traditional active shielding circuit designs are complex, while grounding shields not only reduce the sensor sensitivity but are also unsuitable for grounded sensors. To address this issue, this paper proposes an innovative near-ground (NG) shielding structure. This structure effectively concentrates the electric field between the sensing electrode and ground by adding a common ground electrode around the sensing electrode, thereby reducing the electrical coupling between the metal working surface and the sensing electrode and achieving the desired shielding effect. Through finite element analysis and experimental verification, this study performed an in-depth investigation of the capacitance difference Cd and the rate of change of capacitance with the target distance of sensors under the two mounting methods. The proposed structure achieved a performance comparable with active shielding (17 fF Cd) while operating passively, which addressed a critical cost–adaptability trade-off in industrial CPS designs. The results show that although the performance of the NG shielding was slightly inferior to active shielding, it was significantly better than traditional grounding shielding, and its structure was simple and low cost, showing great potential in practical applications.

Background Hip osteoarthritis (HOA) is a disabling disease affecting around 33 million people worldwide. People of working age and the elderly are at increased risk of developing HOA and the disease is associated with high costs at individual and societal levels due to sick leaves, job loss, total hip replacements and disability pension. This systematic review evaluated the influence of physically demanding occupations on the development of HOA in men. Methods Cohort studies, case–control studies and cross-sectional studies with publications in English or German, which assessed the association between exposure to physically demanding occupations and development of HOA, were searched in electronic databases (Medline, Embase, HSE-Line, Cochrane Library) and conference abstracts from 1990 until May 2020. We assessed the methodological quality of selected studies, interpreted all relative effect estimators as relative risks (RRs) and meta-analytically reviewed the effects of occupations with high physical workloads. All steps are based on a study protocol published in PROSPERO (CRD42015016894). Results Seven cohort studies and six case–control studies were included. An elevated risk to develop HOA was shown for six physically demanding occupational groups. Working in agriculture including fishery and forestry and food production doubles the risk of HOA. Construction, metal working and sales as well as exposure to whole body vibration while driving vehicles increases the risk by roughly 50 to 60%. Unskilled or basic level workers, who were frequently exposed to repetitive heavy manual work, had nearly a doubled risk (RR 1.89 95%CI: 1.29 to 2.77) compared to workers with lower exposure. Conclusions Existing studies state an association between various occupations with high physical workload and an increased risk of developing HOA. High Physical workloads include including lifting and carrying heavy loads, demanding postures, repetitive activities, long standing and running, as well as exposure to body vibrations. Occupational prevention and early detection as well as individual health promotion strategies should place their focus on reducing the impact of high physical strain at work sites.

Introduction. In accordance with the Federal Law of the Russian Federation \"On the Safety of Hydraulic Structures\", it is necessary to ensure the long-term safety and reliability of operating structures at hydroelectric power plants (HPP). In a run-of-river HPP, the \"headwall-turbine hall floor slab\" system serves as the main load-bearing structure, absorbing a variety of external forces and loads during the operation of the turbine hall within the HPP. Over time, surveys have revealed the intensive cracking in reinforced concrete floor slabs, reducing their bearing capacity. To ensure safe operation and prolong the life cycle of the HPP, it is necessary to strengthen the reinforced concrete floor slabs of the turbine hall with external reinforcement, preferably with composite carbon tapes having high strength, low weight, dielectric qualities and other positive characteristics. At the same time, the method of installing carbon tapes should ensure that finely dispersed conductive dust does not form, since the reinforced concrete structures of the HPP turbine hall, saturated with electrical equipment that powers the HPP, are reinforced. It is also necessary to ensure that the operation of the strengthened reinforced concrete floor slab with an external reinforcement system with carbon tapes is monitored over time by means of embedded control and measuring equipment. The solution of the tasks set in the present experimental and computational studies made it possible to substantiate the effectiveness of strengthening the floor slab with external reinforcement based on the use of carbon tapes and to implement it in the HPP turbine hall. Materials and methods. The reinforced concrete floor slab in the HPP turbine hall, which has been subjected to both external and non-design loading during operation, is the object of this study. The cracking and deflections recorded by the surveys led to the need for experimental studies in field conditions, including using a load weighing 150 kN. The stresses in the working metal stretched reinforcement were determined before and after the external reinforcement device with FibArmTape-530/300 carbon tapes. The stress in the carbon tapes was also determined. The experiments of reinforced concrete floor slab models' fragments of the stretched zone were carried out in laboratory conditions in order to determine the effectiveness of the reinforcement using a new method of installing carbon tapes on a concrete surface. These experiments were carried out using a tensile breaking machine and confirmed the positive effect of using a new method of carbon tape device, preventing the formation of finely dispersed conductive dust in the operating electrical installations of the HPP turbine halls. At the same time, the necessary strength of reinforced structures is obtained. In order to determine the formed stress-strain state of the reinforced concrete floor slab of the turbine hall, computational studies were performed taking into account the revealed nature of cracking. Stresses in stretched working reinforcement under various loads before and after strengthening, as well as stresses in carbon tapes, were determined. Using the calculations performed, a schematic diagram of reinforced concrete floor slab strengthening is proposed - the pitch of the carbon tapes and the number of layers of the composite material. Results. From the results of the experimental studies of models fragments of the reinforced concrete floor slab stretched zone that have characteristics of hydraulic structures (concrete of class B15 and B25, low coefficient of reinforcement и, = 0.00445--0.00692, it follows that an increase in strength of 1.62-1.96 times was obtained for composite carbon tapes on a concrete surface strengthened by a new method (applied to HPP). As a result of the strengthening of the reinforced concrete floor slab with external reinforcement using a new method (applied to HPP) for the installation of carbon tapes, as a result of experimental studies in the turbine hall of the HPP, a stress redistribution was established between metal working reinforcement and carbon tapes, which were included in joint work with the floor slab with the formation of tensile stresses in the tapes. Under loading on a reinforced floor slab with 150 kN, the tensile stresses in the metal reinforcement decreased by 1.8-2.9 times (directions - along the flow and across the flow) with the formation of almost equivalent stresses in carbon tapes of the external reinforcement. In order to calculate the changes in the stress-strain state of the floor slab of the turbine hall of the HPP building (with cracking, with support that is not designed in some places under the influence of non-designed loads) strengthening with external reinforcement with carbon tapes, a spatial finite element model was developed and applied. The calculated studies have determined the necessary (from the point of view of ensuring the strength of the floor slab) the pitch of the carbon tapes and the number of layers of composite carbon material. The results of VAT calculations of the reinforced concrete floor slab of the HPP turbine hall, strengthened with external reinforcement with carbon tapes, showed good agreement with the results of the experimental studies. As a result of the comprehensive research carried out, the scope of strengthening of reinforced concrete structures with external reinforcement with carbon tapes has been expanded - use for HPP with a large volume of operating electrical equipment. Conclusion. The conducted studies have demonstrated the effectiveness of the reinforced concrete floor slab of the HPP turbine hall with an external reinforcement system using composite carbon tapes. This is confirmed by the joint work of the reinforcement and the carbon tape - the tensile stresses in both the working reinforcement and the carbon tape are similar in magnitude. At the same time, a new method of installing carbon tape on the concrete floor slab has been experimentally substantiated and applied, preventing the formation of finely dispersed conductive dust, and allowing reinforced concrete structures to be strengthened in operating conditions of HPP electrical installations. The results of the computational studies made it possible to determine the pitch of the carbon tapes and the number of reinforcement layers of the strengthened concrete floor slab, and also showed good agreement with the results of experimental studies. Research has determined the need to equip strengthened reinforced concrete structures with embedded control and measuring equipment in order to control reliable operation for the period of further maintenance. Thus, the complex of experimental and computational studies carried out made it possible to expand the scope of strengthening of reinforced concrete structures using an external reinforcement system based on carbon tapes, up to use in HPP structures, the operation of which is based on the operation of electrical installations.

This article discusses issues related to optimizing the state of East Kazakhstan environment. It is emphasized that along with the industrial progress observed in recent years in the East Kazakhstan region in such sectors of the economy as machinery and metal working, heat and power, woodworking, timber, light and food industries, production of building materials, the level of environmental pollution has increased. The article gives examples of how the activities of the enterprises of metallurgical industry, heat power engineering and motor transport cause a real threat of the environmental crisis in the region. It is concluded that the solution of the environmental problem is possible through comprehensive measures, including the issues of increasing the efficiency of use and protection of water resources, reducing the chemical load on the soil, creating infrastructure for waste processing, improving the health and quality of life of the residents of the region. These measures together can contribute to overcoming the current environmental crisis of the East Kazakhstan region and radically improving the environment as well become the key to optimizing the region’s environment. The methodological basis of the study is the principle of scientific objectivity, which allows analyzing the subject under study taking into account the realities of economic changes in theregion.

Introduction. In accordance with the Federal Law of the Russian Federation \"On the Safety of Hydraulic Structures\", it is necessary to ensure the long-term safety and reliability of operating structures at hydroelectric power plants (HPPs). In a run-of-river HPP, the \"headwall-turbine hall floor slab\" system serves as the main load-bearing structure, absorbing a variety of external forces and loads during the operation of the turbine hall within the HPP. Over time, surveys have revealed the intensive cracking in reinforced concrete floor slabs, reducing their bearing capacity. To ensure safe operation and prolong the life cycle of the HPP, it is necessary to strengthen the reinforced concrete floor slabs of the turbine hall with external reinforcement, preferably with composite carbon tapes having high strength, low weight, dielectric qualities and other positive characteristics. At the same time, the method of installing carbon tapes should ensure that finely dispersed conductive dust does not form, since the reinforced concrete structures of the HPP turbine hall, saturated with electrical equipment that powers the HPP, are reinforced. It is also necessary to ensure that the operation of the strengthened reinforced concrete floor slab with an external reinforcement system with carbon tapes is monitored over time by means of embedded control and measuring equipment. The solution of the tasks set in the present experimental and computational studies made it possible to substantiate the effectiveness of strengthening the floor slab with external reinforcement based on the use of carbon tapes and to implement it in the HPP turbine hall. Materials and methods. The reinforced concrete floor slab in the HPP turbine hall, which has been subjected to both external and non-design loading during operation, is the object of this study. The cracking and deflections recorded by the surveys led to the need for experimental studies in field conditions, including using a load weighing 150 kN. The stresses in the working metal stretched reinforcement were determined before and after the external reinforcement device with FibArmTape-530/300 carbon tapes. The stress in the carbon tapes was also determined. The experiments of reinforced concrete floor slab models' fragments of the stretched zone were carried out in laboratory conditions in order to determine the effectiveness of the reinforcement using a new method of installing carbon tapes on a concrete surface. These experiments were carried out using a tensile breaking machine and confirmed the positive effect of using a new method of carbon tape device, preventing the formation of finely dispersed conductive dust in the operating electrical installations of the HPP turbine halls. At the same time, the necessary strength of reinforced structures is obtained. In order to determine the formed stress-strain state of the reinforced concrete floor slab of the turbine hall, computational studies were performed taking into account the revealed nature of cracking. Stresses in stretched working reinforcement under various loads before and after strengthening, as well as stresses in carbon tapes, were determined. Using the calculations performed, a schematic diagram of reinforced concrete floor slab strengthening is proposed - the pitch of the carbon tapes and the number of layers of the composite material. Results. From the results of the experimental studies of models fragments of the reinforced concrete floor slab stretched zone that have characteristics of hydraulic structures (concrete of class B15 and B25, low coefficient of reinforcement μs = 0.00445÷0.00692, it follows that an increase in strength of 1.62-1.96 times was obtained for composite carbon tapes on a concrete surface strengthened by a new method (applied to HPP). As a result of the strengthening of the reinforced concrete floor slab with external reinforcement using a new method (applied to HPP) for the installation of carbon tapes, as a result of experimental studies in the turbine hall of the HPP, a stress redistribution was established between metal working reinforcement and carbon tapes, which were included in joint work with the floor slab with the formation of tensile stresses in the tapes. Under loading on a reinforced floor slab with 150 kN, the tensile stresses in the metal reinforcement decreased by 1.8-2.9 times (directions - along the flow and across the flow) with the formation of almost equivalent stresses in carbon tapes of the external reinforcement. In order to calculate the changes in the stress-strain state of the floor slab of the turbine hall of the HPP building (with cracking, with support that is not designed in some places under the influence of non-designed loads) strengthening with external reinforcement with carbon tapes, a spatial finite element model was developed and applied. The calculated studies have determined the necessary (from the point of view of ensuring the strength of the floor slab) the pitch of the carbon tapes and the number of layers of composite carbon material. The results of VAT calculations of the reinforced concrete floor slab of the HPP turbine hall, strengthened with external reinforcement with carbon tapes, showed good agreement with the results of the experimental studies. As a result of the comprehensive research carried out, the scope of strengthening of reinforced concrete structures with external reinforcement with carbon tapes has been expanded - use for HPP with a large volume of operating electrical equipment. Conclusion. The conducted studies have demonstrated the effectiveness of the reinforced concrete floor slab of the HPP turbine hall with an external reinforcement system using composite carbon tapes. This is confirmed by the joint work of the reinforcement and the carbon tape - the tensile stresses in both the working reinforcement and the carbon tape are similar in magnitude. At the same time, a new method of installing carbon tape on the concrete floor slab has been experimentally substantiated and applied, preventing the formation of finely dispersed conductive dust, and allowing reinforced concrete structures to be strengthened in operating conditions of HPP electrical installations. The results of the computational studies made it possible to determine the pitch of the carbon tapes and the number of reinforcement layers of the strengthened concrete floor slab, and also showed good agreement with the results of experimental studies. Research has determined the need to equip strengthened reinforced concrete structures with embedded control and measuring equipment in order to control reliable operation for the period of further maintenance. Thus, the complex of experimental and computational studies carried out made it possible to expand the scope of strengthening of reinforced concrete structures using an external reinforcement system based on carbon tapes, up to use in HPP structures, the operation of which is based on the operation of electrical installations.

Metal additive manufacturing (AM) enables the production of high value and high performance components 1 with applications from aerospace 2 to biomedical 3 fields. Layer-by-layer fabrication circumvents the geometric limitations of traditional metalworking techniques, allowing topologically optimized parts to be made rapidly and efficiently 4 , 5 . Existing AM techniques rely on thermally initiated melting or sintering for part shaping, a costly and material-limited process 6 , 7 – 8 . We report an AM technique that produces metals and alloys with microscale resolution via vat photopolymerization (VP). Three-dimensional-architected hydrogels are infused with metal precursors, then calcined and reduced to convert the hydrogel scaffolds into miniaturized metal replicas. This approach represents a paradigm shift in VP; the material is selected only after the structure is fabricated. Unlike existing VP strategies, which incorporate target materials or precursors into the photoresin during printing 9 , 10 – 11 , our method does not require reoptimization of resins and curing parameters for different materials, enabling quick iteration, compositional tuning and the ability to fabricate multimaterials. We demonstrate AM of metals with critical dimensions of approximately 40 µm that are challenging to fabricate by using conventional processes. Such hydrogel-derived metals have highly twinned microstructures and unusually high hardness, providing a pathway to create advanced metallic micromaterials. An additive manufacturing technique that infuses 3D printed hydrogels with metallic precursors leads to metallic micromaterials, providing new opportunities for the fabrication of energy materials, micro-electromechanical systems and biomedical devices.

Sulfur is an important electrode material in metal−sulfur batteries. It is usually coupled with metal anodes and undergoes electrochemical reduction to form metal sulfides. Herein, we demonstrate, for the first time, the reversible sulfur oxidation process in AlCl 3 /carbamide ionic liquid, where sulfur is electrochemically oxidized by AlCl 4 − to form AlSCl 7 . The sulfur oxidation is: 1) highly reversible with an efficiency of ~94%; and 2) workable within a wide range of high potentials. As a result, the Al−S battery based on sulfur oxidation can be cycled steadily around ~1.8 V, which is the highest operation voltage in Al−S batteries. The study of sulfur oxidation process benefits the understanding of sulfur chemistry and provides a valuable inspiration for the design of other high-voltage metal−sulfur batteries, not limited to Al−S configurations. The sulfur cathode in metal-sulfur batteries normally undergoes electrochemical reduction to form metal sulfides. Here, the authors demonstrate the electrochemical oxidation of sulfur in ionic liquid for high-voltage aluminium-sulfur batteries.

Oxygen release and irreversible cation migration are the main causes of voltage fade in Li-rich transition metal oxide cathode. But their correlation is not very clear and voltage decay is still a bottleneck. Herein, we modulate the oxygen anionic redox chemistry by constructing Li 2 ZrO 3 slabs into Li 2 MnO 3 domain in Li 1.21 Ni 0.28 Mn 0.51 O 2 , which induces the lattice strain, tunes the chemical environment for redox-active oxygen and enlarges the gap between metallic and anionic bands. This modulation expands the region in which lattice oxygen contributes capacity by oxidation to oxygen holes and relieves the charge transfer from anionic band to antibonding metal–oxygen band under a deep delithiation. This restrains cation reduction, metal–oxygen bond fracture, and the formation of localized O 2 molecule, which fundamentally inhibits lattice oxygen escape and cation migration. The modulated cathode demonstrates a low voltage decay rate (0.45 millivolt per cycle) and a long cyclic stability. Voltage fade is a critical issue for Li-rich transition metal oxide cathode. Here, the authors modulate the oxygen anionic redox chemistry and enlarges the gap between metallic and anionic states by constructing Li 2 ZrO 3 slabs into Li 2 MnO 3 domain in Li 1.21 Ni 0.28 Mn 0.51 O 2 which fundamentally suppresses the voltage decay.

An extensive range of metals can be dissolved and re-deposited in liquid solvents using electrochemistry. We harness this concept for additive manufacturing, demonstrating the focused electrohydrodynamic ejection of metal ions dissolved from sacrificial anodes and their subsequent reduction to elemental metals on the substrate. This technique, termed electrohydrodynamic redox printing (EHD-RP), enables the direct, ink-free fabrication of polycrystalline multi-metal 3D structures without the need for post-print processing. On-the-fly switching and mixing of two metals printed from a single multichannel nozzle facilitates a chemical feature size of <400 nm with a spatial resolution of 250 nm at printing speeds of up to 10 voxels per second. As shown, the additive control of the chemical architecture of materials provided by EHD-RP unlocks the synthesis of 3D bi-metal structures with programmed local properties and opens new avenues for the direct fabrication of chemically architected materials and devices. Inkfree multi-material printing is a common challenge in 3D printing. Here, the authors introduce electrohydrodynamic redox printing, a method that enables the deposition of multiple metals and their alloys with nanoscale resolution and thus the synthesis of materials with locally tuned properties.