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Understanding the potential distribution in liquids is critical due to its significant differences from general media. The main problem addressed in this research is the lack of clarity on how electrode polarization affects potential distribution in liquid electrolytes. To investigate this, we experimentally measured the potential distribution characteristics in liquids under DC and AC voltages, explaining the variability through electrode polarization theory. Our action included introducing electrode polarization potential correction in COMSOL software simulations, which showed strong agreement with our experimental results. Further, we investigated the potential distribution characteristics in Na2SO4 solutions with varying concentrations, using ionic potential to explain voltage formation inside the liquids. The results highlight the improved accuracy in modeling potential distributions in liquid electrolytes, which is significant for advancing various electrochemical processes.

Electrocardiogram (ECG) signals often encounter various types of noise interference, which annihilates their waveform characteristics and exhibits strong instability. To facilitate clinical diagnosis and analysis, it is necessary to perform denoising processing in advance. A denoising method for ECG signals based on variational mode decomposition (VMD) and recursive least square (RLS) has been proposed. VMD was used for the modal decomposition of noisy ECG signals, and the recursive least square (RLS) algorithm was used for adaptive filtering of various intrinsic mode functions (IMFs) components. The problem construction, solution, and decomposition characteristics of VMD were analyzed. The IMFs filtered by RLS were reconstructed. This achieved the elimination of interference noise in the ECG signal. The Sym8 wavelet basis, LMS, NLMS, RLS, and VMD-RLS denoising method were compared by using ECG signals including Gaussian white noise, baseband drift, electrode motion, electromyographic interference, and electrical interference noise. The experimental results showed that the VMD-RLS denoising method has significantly better denoising performance than the other four methods, achieving better values in the quantitative evaluation indicators. This algorithm improved convergence speed and signal estimation accuracy, and it has good effectiveness, superiority, and practicality. Therefore, the VMD-RLS denoising method can enable doctors and researchers to analyze and diagnose ECG signals of heart diseases more accurately.

This theoretical research is part of the educational and scientific project “Bioelectronic medicine or look at medicine differently” of research work of the Department of Internal Medicine and Emergency Medicine of Poltava State Medical University (23, Shevchenko St., 36011, Poltava, Ukraine) on “Development of algorithms and technologies for implementing a Healthy Lifestyle in patients with Non-Communicable Diseases (NCDs) based on the study of functional status” (state registration number 0121U108237: UDC 613 616-056-06: 616.1 / 9-03). The aim of this theoretical research was to create a systemic medical analysis of the nutrition of the scientific evidence of the Vega Test Method in the complex clinical treatment of patients with Non-Сommunicable Diseases, to determine the current state of health problems and prospects for using the method from the perspective of Complex Medicine. Conclusions: Vega Test Method is a promising modern science-intensive computerized instrumental technique that should be introduced into Clinical Medicine for the examination of patients with NCDs. Existing problems of introducing the Vega Test Method into Clinical Medicine are solved thanks to the progress of fundamental science and Quantum Physics, which leads to a paradigm shift in views on the functioning of the human body. The Vega Test Method has a modern scientific biophysical justification of validity mechanisms based on knowledge of the Magneto-Electrochemical Theory of Metabolism and Life, the Theory of the Electromagnetic Field, and the Concept of Biophoton Signaling. The use of the Vega Test Method in Clinical Medicine for the examination of patients with NCDs is important for the development of Complex Medicine.

Reducing the energy consumption of robot manufacturing systems has become one of the increasingly important issues in industry. However, for robot manufacturing systems, the traditional optimization method with energy consumption as the objective function always suffers from low efficiency. In view of this, a novel energy-saving optimization method is proposed for robot laser welding systems based on the multi-objective optimization in this paper. This method deconstructs the energy consumption objective into three computationally inexpensive feature objectives and uses these three feature objectives as the objective functions of optimization, thus significantly improving the optimization efficiency. And a comprehensive optimization model of robot laser welding systems, which simultaneously considers three factors: the layout pose of workpieces, the posture of laser tools, and the inverse kinematics solution of robots, is established by utilizing a task energy characteristic model based on the time-scaling method. Furthermore, an integrated optimization process based on the NSGA-II algorithm is presented. A case study is described in detail. The results of the case study demonstrate that the proposed optimization method leads to a remarkable increase of over 95 % in optimization efficiency, that three factors exhibit interdependence, and that the integrated optimization of these factors yields superior results compared to optimizing them individually. In the case study, at a 95 % confidence level, the optimization scheme reduces the energy consumption of idle motion by 34.91 % and the total energy consumption by 7.29 %, compared to the original scheme.

This paper presents an investigation into the nonlinear dynamic behaviors of the floating raft isolation system coupled with quasi-zero-stiffness isolators subject to multiple disturbance sources. First, the coupling effects between the excitation source and isolation system are considered. Also, the floating raft isolation model under multiple excitations and its motion equation are deduced, and then the dynamic responses are mainly investigated by using the techniques of time history diagram, spectrum diagram, phase diagram and Poincaré map, and the bifurcation diagram. Finally, the bifurcations of the mechanical isolation system with different parameters are analyzed through numerical methods, especially the effect of center distance and mass ratio. The result predicts that the floating raft shows an alternate phenomenon of periodic motion, quasi-periodic motion, and chaotic motion when the center distance and mass ratio vary. The motion state of the floating raft vibration isolation system is more sensitive to the mass ratio than to the center distance. The horizontal and rotational response of the system becomes very intense in the chaotic state, and the response amplitudes in the horizontal and vertical directions reach the same order of magnitude. Above all, the dynamic characteristics can provide the theoretic supporting for the dynamics, vibration control and its parametric optimization of the floating raft isolation system coupled with quasi-zero-stiffness isolators. This study will lay down the requirements for the engineering design and application of floating raft isolation equipment in large vessel.

The multi-degree-of-freedom engine mount system presents a coupling issue that significantly impacting its vibration isolation performance. Although the optimization theories for decoupling 6-degree-of-freedom (6-DOF) and 12-degree-of-freedom (12-DOF) engine mount systems are relatively well-developed, previous studies have predominantly focused on engine response and often overlook the impact of car body vibrations. To address this gap, this article conducts an in-depth investigation into how the elasticity of the car body affects the vibration isolation performance of the engine mount system. Initially, the dynamics of the engine mount system are modeled with 6 degrees of freedom, incorporating an elastic base with 9 and 12 degrees of freedom, respectively. The study then analyzes how body elasticity influences the natural frequencies and modal shapes of the engine mount system. Subsequently, the sensitivity of the engine mount system is assessed using Isight analysis to evaluate the three directional stiffnesses of the mount. Finally, the decoupling optimization of the 12-degree-of-freedom engine mount system is performed using the NLPQL (Sequential Quadratic Programming) method. The findings indicate that: (1) considering the car body’s influence directly affects the natural characteristics and decoupling efficiency of the engine mount system; (2) body elasticity in the Z-direction has the greatest impact on the system’s vertical natural frequency; and (3) the NLPQL method effectively enhances the decoupling rate of the engine mount system.

Continuous developments in the field of 3D printing techniques and equipment have enabled their usage in the field of electronics structures, circuits, and device fabrication in addition to many other fields. This advancement has enabled the potential fabrication of sensors using silicon-based micro or even Nanoelectronics. Currently, the manufacturing and packaging of such devices and structures are heavily reliant on lithography, which can be slow and can involve substantial processing requirements. In this paper, a temperature-sensing Interdigital Transducer (IDT) structure was designed and fabricated using Direct Laser Writing (DLW) based on Two-Photon Lithography (TPL), which is a high-resolution 3D printing technology. The TPL in a positive photoresist was combined with the physical vapor deposition method and the lift-off process to create gold IDT microstructures. The developed sensing structures were characterized using a network analyzer to determine the resonance frequency and its dependence on the temperature changes. The results showed that the IDT structures exhibit a linear response toward the changes in temperature with an average sensitivity of 0.123 MHz/°C. The most important advantage in producing the IDT structure with the additive manufacturing technique is that a very small-sized structure is produced error-free and efficiently.

In CCUS ZEN project one of value chains considered includes emission sources located in the region of northern Poland. The value chain is intertwined with the scope of ECO2CEE Project of Common Interest on CO2 terminal in Port of Gdańsk. The ECO2CEE project in its first stage is to include railway transport of CO2 captured in two of the installations of the studied value chain. Carbon dioxide delivered to the terminal is to be transported by ship and stored under North Sea. However, within the region and its immediate vicinity there is notable storage potential. About 120 km north of Gdańsk, offshore, there is saline aquifer in Cambrian sandstones of storage capacity likely sufficient to store emissions of all selected 16 emitters of the region. The main barrier to such approach is the interpretation of Article 11 of Helsinki Convention suggesting ban of CO2 storage under the Baltic Sea. In southern part of the region where also ECO2CEE emitters are located there are several saline aquifer structures in Lower Jurassic and Lower Cretaceous of estimated storage capacity significantly exceeding the possible demand of emitters of the local cluster. Hence, the work is to propose the further development of the PCI value chain in northern Poland, beyond the original concept.