bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic behavior of a wheeled rocket launcher using transfer matrix method of multibody system
Authors: Eisa H , Ahmed M Y M , Khalil M , Saleh S
Published: August 2024

One of the most sophisticated causes of unguided rocket dispersion is the uncertainties in launch conditions. This arises due to the fact that a launcher, in reality, shows dynamic behavior as it is a multibody system. This paper investigates the dynamic behavior of a wheeled rocket launcher that is loaded on a vehicle. The launcher and vehicle system are modeled as a multibody system using the transfer matrix method of multibody system (TMM). TMM is chosen due to its suitability for linear systems and its ability to obtain the overall transfer matrix for the entire system by performing successive matrix multiplications of the individual body’s matrix, thereby avoiding the complexity of solving the overall dynamic equations of the system. The developed dynamic model is then validated by comparing its results with those in the open literature using the Lagrange approach. The study considers dynamic loads that result from the rocket motion on the launcher. A parametric study is conducted to address the impact of launcher structural aspects. By investigating the dynamic behavior of the wheeled rocket launcher, this study aims to enhance the understanding of its performance.
Capacity optimization of a large-scale photovoltaic power generation system coupled with hydrogen production and storage based on economic analysis
Authors: Zhang Sheng , Li Bo , Xu Dongjie , Zheng Jinyang
Published: August 2024

The renewable energy system coupled with hydrogen storage has proven to be a suitable method to reduce the variability of output power and meet stable hydrogen supply demand. However, the excessive cost of hydrogen through water electrolysis using renewable energy restricts its application, and the capacity configuration of electrolyzers and gaseous hydrogen storage tanks is affected by the immoderate reliance on engineering experience, leading to the unbalance of generation side and hydrogen demand side. In this study, a 300 MW photovoltaic power generation system has been proposed to fit the raw material demand of a synthetic ammonia plant, i.e., around 1000 kg/h hydrogen. A simplified mathematical model including an electrolyzer and a hydrogen tank is proposed to get the best capacity configuration. The levelized cost of hydrogen (LCOH) is chosen as an optimization function, and a particle swarm optimization algorithm is adopted to get the optimal results. The simulation results indicate that the optimal capacity configuration is 176.36 MW for the electrolyzer and 14644.2 Nm3 for the hydrogen tank, and the LCOH is 30.31 Yuan/kg. Compared with the empirical model, the LCOH based on the optimization model is 8.87% lower than that of the empirical model, indicating better economic benefits of the optimization model.
Design and optimization of zero-carbon integrated energy system for highway service area
Authors: Wu Simin , Gao Yanyu , Tang Ruoshi , Cai Liang , Du Yang , Guo Lingyu , Yang Zhongguang
Published: August 2024

The challenge of achieving dual-carbon targets arises from the issue of high carbon emissions in Chinese highway service areas. To address this, a comprehensive electric-thermal-hydrogen energy system is proposed, consisting of a new energy generation system, heat pumps, electrolyzers, hydrogen fuel cells, energy storage devices, and charging stations. A dispatch model for the integrated energy system is established, with the objective of minimizing the total operating cost while satisfying the constraints of each device and the electric-thermal-hydrogen balance. The model is implemented in MATLAB, and the ideal optimal solution for each decision variable is obtained using the Gurobi solver. The investment and operating costs, as well as the scheduling results for electricity, heat, and cooling, are analyzed. The results indicate that the electrolyzer-fuel cell system can improve the system’s operational stability and flexibility in dispatch optimization. Due to the instability of photovoltaic and wind power devices and the fluctuating nature of loads, energy storage devices are required for peak load shaving in the system. The zero-carbon integrated energy system model can calculate the most economical investment plan based on the load and meteorological conditions of different service areas.
Optimization of rural integrated energy system considering carbon emissions
Authors: Sun Ruonan , Su Juan , Du Songhuai
Published: August 2024

The country’s objective of achieving “carbon neutrality” has necessitated transforming and upgrading rural energy systems. Establishing a comprehensive rural energy system is crucial to accelerate the development of a clean energy system in rural areas. This paper addresses the context of China’s “carbon neutrality” goal and presents a model for a rural integrated energy system that incorporates electricity, biomass energy, and PV. The model aims to optimize the capacity of energy devices while considering economic and environmental factors. Practical case studies are conducted to validate the feasibility of the proposed model.
Research on the photoelectricity mismatch loss of photovoltaic and thermal (PV/T) units connected in series at different temperatures
Authors: Zhu Chao , Chen Ziyu , Quan Chen , Dong Le , Feng Haoliang
Published: August 2024

A simulation study was conducted on the mismatch loss caused by temperature differences between photovoltaic and thermal (PV/T) modules connected in series. A calculation method for the IV curve of PV/T modules connected in series was proposed, and an equivalent circuit model of PV/T units was established using Multisim software. Two different temperature zones, three different temperature zones, and four different temperature zones of PV/T units connected in series were separately established. A numerical calculation model based on the Lambert W function was used to study the series mismatch characteristics of PV/T cells at different temperature ranges. The series connection method of PV/T modules obtained through experimental comparison research: (1) The maximum temperature difference of PV/T modules in the series should be controlled within the range of 10-20°C as much as possible; (2) The temperature of adjacent PV/T modules in the string should achieve continuous distribution; (3) Considering that the maximum operating current of a concentrated PV/T system is greater than that of a regular photovoltaic system, it is necessary to reduce the system output current and increase the system output voltage as much as possible in engineering. A series connection should be the main connection method for a string connection.
Harmonic absorption method for cement kiln power supply system under clean energy integration
Authors: Chen Xiao , Hu Gaoping , Hu Quangan , Liu Mingtong , Chen Yunfei
Published: August 2024

To maintain the normal operation of the power supply system, a method for harmonic absorption in the cement kiln power supply system under clean energy access is proposed. We design a data acquisition structure for the cement kiln power supply system and extract the harmonic current signal of the power supply system through variational mode decomposition, harmonic compensation for the cement kiln power supply system under clean energy integration, and harmonic absorption of cement kiln power supply system through the current equivalent model. The experimental results show that the harmonic signal extraction accuracy of this method is high, and the difference between the consumed discharge power and the power demand is minimal. It can achieve a balance between power supply and demand through harmonic compensation, which is conducive to the stable operation of the power supply system.
The development characteristics and prospect of pumped storage power station as the main energy storage facility in China under the background of double Carbon
Authors: Zhao Kaili , Wang Jue , Qiu Liuchao , Wang Wei
Published: August 2024

Intending to reach the peak of carbon and carbon neutrality, to become a global consensus, and to achieve the goal of “reaching the peak of carbon emissions before 2023 and carbon neutrality before 2060”, China proposed in March 2021 to construct a new power system with new energy as its core. For the realization of the above goals, the construction of a pumped storage power station is quite important, and it is the key to the realization of green and low-carbon energy transformation and has a crucial impact on the achievement of China’s “double carbon” goal. This paper first introduces the related concepts of dual-carbon background and pumped storage power stations. Then the development dynamics of the station in a period are analyzed to obtain its characteristics, such as wide distribution, fast construction, and variety. Finally, this paper puts forward and summarizes the suggestions and prospects of pumped storage power stations for China’s new energy growth.
A study on long-term industrial electricity consumption and carbon emission forecasting methods based on TimesNet models
Authors: Feng Xiaowei , Fu Jiayu , Zhang Zhili , Li Jingjie , Li Tianyu , Zhao Minrui
Published: August 2024

Aiming at the prediction problem of industrial electricity consumption and carbon emission, a TimesNet model is established to improve the accuracy of industrial electricity consumption and carbon emission prediction. Five significant influencing factors were screened out by grey correlation analysis; based on the energy consumption dataset of an iron and steel enterprise in 2023, the dataset was preprocessed and inputted into the TimesNet model, the prediction results were integrated and summarized, and the prediction results of the DLinear, LightTS, PatchTST, and iTransformer time series prediction models were compared and analyzed. The results show that the predicted values of the TimesNet model fit the actual values, and its mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), and mean absolute percentage error (MAPE) are 0.31, 0.36, 0.6, and 1.12, respectively, which are better than those of the other models. It proves that the model can predict industrial electricity usage and release of carbon more accurately, providing a practical method for industrial electricity usage and release of carbon prediction.
Comprehensive benefit evaluation of Carbon reduction in power transmission and transformation projects by TOPSIS method based on combination weighting
Authors: Xin Cheng , Wang Shuo , Wang Yinan , Yao Fan , Xu Weimao , Chen Biao
Published: August 2024

With the continuous promotion of carbon peak carbon neutrality, the investment and construction of new power systems have accelerated, and the construction of a low-carbon economy has become an inevitable trend of the transformation and development of power transmission and transformation projects. In this paper, the FAHP and entropy methods are used to evaluate the economic, social, and social benefits of carbon reduction in power transmission and transformation projects and finally establish a set of comprehensive benefit evaluation systems for carbon reduction in power transmission and transformation projects. Under this evaluation system, the comprehensive benefit of 220 kV power transmission and transformation project in A province is sorted by entropy weight-TOPSIS method. The comprehensive benefit of power transmission and transformation project B >C >A project is finally obtained. At the same time, in the sub-criteria of economic benefits, the index of “enterprise asset-liability ratio” has the largest comprehensive weight. The “using distributed energy generation” index has the largest comprehensive weight in the sub-criteria layer of carbon reduction benefit. In the subsequent construction of power transmission and transformation projects, enterprises can prioritize improving the above indicators to improve carbon reduction efficiency and economy.
Enhanced vanadium redox reaction catalytic properties enabled by tunning oxygen vacancy in rutile tio2 coated graphite felt electrodes
Authors: Liu Yancai , Duan Xiaobo , Wang Haonan , Yu Jiaao , Zhou Jian , Lu Birou , Zhu Ming , Zheng Bin , Zhang Lei
Published: August 2024

Catalyzing vanadium redox reactions in VRFBs with transition metal oxides is an effective and affordable approach. In this study, the surface electron distribution of TiO2 was regulated by introducing oxygen vacancies into its lattice, enabling the electrode to exhibit outstanding catalytic efficacy in VO2
+/VO2+ and V3+/V2+ redox transformations and suppress the detrimental side reaction (HER and OER) simultaneously. Benefiting from the enhanced catalytic activity and selectivity, the 1000-TiO2-GF electrode sustained a stable operation for 100 cycles at 120 mA cm−2 with no discernible efficiency degradation. The DFT results indicate that oxygen vacancy in TiO2 provides more extra electrons to its neighboring titanium, further strengthening the interaction between the electron-rich titanium and oxygen in VO2
+/VO2+, thus enhancing its catalytic performance. The enhanced catalytic activity for V3+/V2+ on oxygen vacancy-rich TiO2 coating can be attributed to the effective suppression of hydrogen evolution reaction, which can occupy active sites exclusively and produce detrimental H2 bubbles. This insight provides valuable guidance for the innovative design of catalysts in vanadium redox flow batteries.
Study on photovoltaic combined air source heat pump heating system under typical meteorological conditions
Authors: Wang Litao , Wang Shuaijie
Published: August 2024

This paper proposes a photovoltaic (PV) combined air source heat pump heating system for rural areas in severe cold regions of northern China, where the current clean heating methods have high costs and low efficiency. The paper uses meteonorm8 and TRNSYS software to derive the typical meteorological parameters and simulate the system performance in a guard room in Shenyang city. The paper analyzes the heat pump power consumption, PV cell power generation, and economic and environmental benefits of the system under different outdoor temperatures in the heating season. The results show that the system can meet the heating demand and maintain a comfortable indoor temperature, with an annual cost of 1603 RMB, which is 61.33% lower than a single heat pump system. The system can also reduce the emissions of carbon dioxide, sulfur dioxide, and dust by 2619.43 kg, 10.78 kg, and 6.91 kg per year, respectively, demonstrating its economic feasibility and environmental contribution.
Research on the coupling mechanism of transient overvoltage in large-scale new energy station grid connection
Authors: Hou Kaiyun , Ren Bixing , Zhang Ziao , Li Qiang , Li Yansong , Liu Jun
Published: August 2024

The large-scale new energy station transmission system is relatively weak, and long-distance transmission is prone to transient overvoltage. The hysteresis of the control loop of the Static Var Generator (SVG) can also contribute to the increase of transient overvoltage. Therefore, this article first establishes a photovoltaic power generation model, SVG model, and photovoltaic grid-connected system. Secondly, the transient overvoltage coupling mechanism of photovoltaic grid-connected systems under various faults such as commutation failure, DC blocking, and DC restart was analyzed through PSCAD simulation. At the same time, the changes in transient overvoltage before and after the installation of SVG were compared, and SVG’s reactive power dynamic behavior was analyzed. Finally, the mechanism of SVG assisting in increasing transient overvoltage was summarized.
An automatic recognition method for power quality disturbances based on CAB-Net
Authors: Wang Minghao , Wang Liqiang
Published: August 2024

The accurate identification of power quality disturbances (PQDs) is crucial for maintaining the stability and reliability of power systems. In this paper, an automatic identification method for PQDs based on CNN-BiGRU-Attention Network (CAB-Net) is proposed. To handle the temporal characteristics and complexity of composite PQDs signals, the proposed model leverages the bidirectional information transmission of the BiGRU model to efficiently extract temporal features. Furthermore, to boost recognition accuracy, an attention mechanism is incorporated, the key information can be intelligently locked in the feature extraction stage, and the information can be efficiently screened and utilized, thereby enhancing its ability to identify power quality disturbance signals. To confirm the validity of the method, we use the simulation data for experimental proof. Experimental results demonstrate that compared to traditional power quality disturbance identification methods, the method has excellent recognition ability and stronger robustness.
A Low voltage AC fault arc detection method based on multi-feature fusion
Authors: Li Zhaoqiang , Liu Yang , Liang Zhihua , Huang Ying
Published: August 2024

The complex electrical environment makes it difficult for most arc detectors on the market to accurately detect faulty arcs. A universal fault arc detection method based on machine learning (ML) algorithms is proposed in this paper. To address the potential hazards of fault arcs in the power system, firstly, the causes, time-domain, and frequency-domain characteristics of fault arcs were analyzed. Then, an arc experiment platform was built according to national standards, and current data was collected under various load conditions. Finally, the arc detection model was trained based on ML. The main contribution of this study is to explore a feature combination that is not affected by load type interference and has strong generalization ability for identifying fault arcs, clarify the key factors and feature extraction methods for identifying fault arcs, and develop a set of high-precision arc detection methods, providing strong guarantees for the stable operation of the power system.
Comparative study of electric power structure of hydrogen fuel cell electric propulsion ship system
Authors: Cai Huiyin , Sui Huiran , Li Zhenyu , Wu Wenbin
Published: August 2024

Aiming at the problem of the applicability of active and semi-active structures of hybrid energy storage units to the complex working conditions of ships in the hydrogen fuel cell electric propulsion system of ships, a comparative study of such structures is carried out in terms of the control strategy, capacity design and optimization effect, respectively. The hybrid energy storage unit in the active structure, supercapacitor and battery, are both connected to the DC bus through the converter. In the hybrid energy storage unit in the semi-active structure, the battery is connected to the low-voltage DC bus through the converter flow in parallel with the supercapacitor, and then connected to the DC bus through the converter. Two kinds of hydrogen fuel cell electric propulsion ship system topology simulation models were established by MATLAB/Simulink respectively, and simulation verification was carried out. The simulation results show that the hybrid energy storage unit with an active structure has stronger adaptability in complex working conditions during ship operation.
Research on characteristics of radio interference of MMC-HVDC lines
Authors: Wang An
Published: August 2024

Previous research on radio interference in DC lines has focused on radio interference caused by corona discharge. But with the development of Modular Multilevel Converter Based High Voltage Direct Current (MMC-HVDC) systems, high frequency signals generated by fast switching of Insulate-Gate Bipolar Transistor (IGBT) are transmitted to Direct Current (DC) lines and radiate radio interference outward. On the one hand, the radio interference formula recommended by the dual-level DC transmission line recommended by International Special Committee on Radio Interference (CISPR) is calculated by the radio interference generated by the line corona discharge; On the other hand, by establishing a MMC-HVDC line model, analyse the high frequency signal transmission generated by the fast switching of IGBT in the Modular Multilevel Converter (MMC) to the radio interference generated by radiating outside the DC line. The results of the study show that the radio interference generated by high -frequency signals of IGBT fast switching will decrease with the length of the line. The radio interference value generated by corona discharge is 47.43 dB(μV/m), the radio interference generated by the high-frequency signal of IGBT fast switching is 40.83 dB(μV/m), which is too small than the radio interference of corona discharge.
Simulation study on acoustic performance of Tonpilz piezoelectric transducers
Authors: Wang Ying
Published: August 2024

The Tonpilz configuration of transducers is recognized for its capability to generate high-power acoustic emissions at relatively lower frequencies, which is a prevalent setup in sonar systems. Comprising a frontal radiating element, a rear casing, and a piezoelectric ceramic ring sandwiched between them and affixed by a central bolt, this study delineates the inclusion of bolt pretension impact. The investigation assesses the structural and acoustic ramifications of the transducer’s frequency response. These findings indicate the commendable acoustic performance of the transducer.
Research and application of composite insulator overheat identification method based on improved case segmentation
Authors: Rao Chengcheng , Liu Gao , Li Changyu
Published: August 2024

How to quickly and accurately locate the heat of power components is one of the problems that need to be discussed frequently in the power field. At the same time, due to the diverse types of equipment in the power industry and the complex environment, if the heating position of the components cannot be located in time and further safety measures are taken, it will greatly affect whether the line can run stably. Based on infrared images, the device can be detected at a distance, and the problem can be found without interrupting its working state, which is more efficient in the process of equipment inspection. At present, some algorithms are based on infrared image research, but the positioning is not accurate, and some problems such as the temperature extracted by the algorithm and the temperature deviation between the actual parts caused by environmental factors, have not been a perfect solution. With regard to these problems, this paper presents a new method for overheating identification of composite insulators. First, the external profile of composite insulators is identified in infrared images through the YOLOV5 instance segmentation algorithm, and the rod core position of composite insulators is located based on this external profile. Then, the temperature matrix of the rod core position is obtained through the original heat matrix in infrared images. By comparing the temperature of the temperature matrix, we can determine whether the temperature is abnormal. In the actual production environment, the accuracy rate of the proposed method is 0.84, the error detection ratio is 0.2, and the total time of the algorithm is 216 ms. The results show that the proposed method has a good component positioning effect and can filter most of the temperature identification errors caused by environmental factors. It provides a new solution to solve the problem of temperature anomaly identification of overhead line power equipment in different scenarios.
Life prediction of lithium battery based on particle filter and BP neural network
Authors: Zhou Jixiang , Huang Weijian , Li Yuhan , Wang Zhiyun
Published: August 2024

This paper focuses on using Particle Filter (PF) and Back Propagation (BP) neural networks for RUL prediction. This fusion strategy uses particle filtering (PF) for battery system state estimation and prediction while considering various types of noise and uncertainties to assess the system state comprehensively. Furthermore, the strategy employs a BP neural network to learn and combine historical data patterns with particle filtering estimation, improving prediction accuracy and reliability. This study validates the proposed fusion method by comparing it with the original PF and BP prediction methods using Toyota Motor Corporation and Stanford University datasets. The experimental results demonstrate its superior performance and higher prediction accuracy.
Modeling simulation and output characteristic analysis of PEMFC
Authors: Wang Jieyu , Zhang Kaige
Published: August 2024

Facing the dual problems of environmental pollution and energy shortage, PEMFC has become a research hotspot because of its high energy conversion efficiency and non-pollution. In this paper, theoretical voltage and various loss voltages of PEMFC were analyzed in detail, and PEMFC was modeled in Simulink using an empirical formula. The influence of temperature, gas pressure, and film water content on output characteristics of PEMFC was explored by using the control variable method, and it was concluded that the parameter values of the three could be improved within a certain range. Both can improve the output characteristics of PEMFC, which provides certain reference significance for the control of PEMFC.
Investigation methods for enhancing the energy consumption capacity of novel PV access distribution networks
Authors: Tian Shiji , Wang Hongkun , Gong Jianfeng , Zheng Wei , Han Yiming , Zhang Bin
Published: August 2024

This paper presents a method for reconstructing distribution networks using soft open point (SOP) and demand response (DR) energy storage, which can effectively solve the problems of voltage overruns, line overcurrent, and bidirectional flow currents caused by the photovoltaic (PV) getting into the distribution network. First, the model for the rebuilding of the distribution network is created by using the energy storage method of DR and SOP. Then, MISOCP, which stands for mixed-integer second-order cone programming, is the model that is used to change the distribution network reconfiguration, and the transformed model is solved by the MOSEK algorithm package in MATLAB. Finally, the strategy suggested in this research may successfully enhance the distribution grid’s consumption capacity after PV access, as shown by the verification in the IEEE33 node distribution grid system.
An adversarial network reinforcement method for power data time series generation based on knowledge transfer and Rayleigh differential privacy
Authors: Zhai Feng , Li Baofeng , Liang Xiaobing , Qin Yu , Ji Wen
Published: August 2024

In order to solve the problem of sensitive information leakage of power data in machine learning and artificial intelligence processing, this paper proposes a method of civic-text data reinforcement based on time series generation adversarial network, which combines knowledge transfer and Rényi differential privacy protection framework to balance privacy and availability, while improving the accuracy of the model. First, the generative adversarial network generates training data that is similar to the real data but secure through adversarial learning, ensuring that even if the data is stolen, the original information cannot be inferred. Secondly, through the integration of recurrent neural network training and autoencoder, the dynamic and static characteristics of the power load data can be effectively captured, and the high dimension of the learning space can be reduced. In addition, knowledge distillation technology is used to guide the generator of training student models through a powerful teacher network of knowledge transfer, improving the diversity and quality of the generated data. Finally, from the four aspects of privacy, data similarity and diversity, and practicability, the practical application value and potential of the framework for electricity consumption data are comprehensively evaluated.
A wide area backup protection algorithm based on fault current comparison and evidence theory fusion
Authors: Hu Ting , Jia Ke , Bi Tianshu , Dong Xuezheng
Published: August 2024

Wide-area backup protection using information in the area to determine the fault location comprehensively requires a high fault tolerance ability. However, the traditional wide area backup protection algorithm based on evidence theory assigns a separate value to each adjacent line for its fault probability, and the performance of the algorithm degrades in the condition of more information loss or errors. To solve these problems, this paper proposed a wide area backup protection algorithm based on fault current comparison and improved evidence theory fusion. The proposed method first selects the suspected fault lines by sequence voltage sorting. Then, the information on the fault current sequence component and traditional protection action is collected and preprocessed to form the evidence set, and its basic probability assignment is calculated. Finally, the improved evidence theory is used for fusion to identify fault lines. Simulation results show that the algorithm can accurately identify fault lines under complex operating conditions, multiple information loss and errors, and has high fault tolerance.
Virtual inertia control of distribution grids under automobile charging and discharging load uncertainty
Authors: Huang Zhifeng , Huang Peng , Ge Jing , Qiu Xi , Fang Ying
Published: August 2024

Automobiles with unstable charging and discharging loads usually have unstable power, frequency, and other parameters of the distribution network. Therefore, a virtual inertia control strategy is proposed to enhance the distribution network’s stability and improve the grid’s voltage quality. This method can enhance the inertia control capability of the grid by incorporating the sag coefficient and SOC control, which in turn achieves the purpose of improving the grid’s reliability. The results show that changing the sag coefficient can enhance the voltage stability to reduce the impact of the battery while incorporating the SOC inertia coefficient control, the distribution grid operation will be more stable, and the power quality will be higher. The new method enhances the stability of voltage load to a certain extent and lays the foundation for the subsequent virtual inertia control technology.
Research on virtual inertia of energy storage systems under different grid-forming control strategies
Authors: Lv Junzhang , Yang Li , Yue Chao , Han Mingliang , Chen Jingyi
Published: August 2024

To reasonably evaluate the support capability of grid-forming energy storage in power systems characterized by “double high” characteristics, it is essential to investigate the factors influencing the virtual inertia of grid-forming energy storage. This paper delves into the relationship between two control strategies of grid-forming energy storage and virtual inertia from an energy perspective. Initially, the operational principle and technological advantages of grid-forming energy storage are analyzed. Subsequently, based on the principles of two grid-forming control strategies, mathematical models for both types of grid-forming energy storage are established, elucidating the physical significance of virtual inertia in grid-forming inverters and revealing the adjustability of virtual inertia. Finally, a microgrid simulation system is constructed in PSCAD to validate the theoretical analysis.
Cascaded H-bridge power carrier communication method based on harmonic injection
Authors: Liu Fang , Liu Jianzhao , Bian Yuanyuan , Geng Qing
Published: August 2024

Scaded H-bridge inverter systems are widely used, but there are complex communication problems between multiple module communications. In this paper, a power carrier communication method injecting the third harmonic is proposed for a single-phase cascaded H-bridge system. The third harmonic is superimposed on the SPWM sinusoidal waveform as a modulating signal and demodulated from the acquired current signals by means of DQ conversion. The baseband input signals are directly observed from the Id and Iq signals. There is no need to add additional communication lines. The method is simple and reduces costs.
Multiple sliding contact of viscoelastic solids: Modelling and experiments
Authors: Torskaya E V , Morozov A V , Stepanov F I
Published: August 2024

The paper presents the results of friction tests of paving slabs in contact with rubber. The roughness of the slabs surface is formed by shot blasting. Some of the samples were slightly polished to simulate wear. The results of roughness measurement were adopted for modeling and used to calculate the effect of surface treatment on the deformation component in sliding friction. The results of modeling and experiments at room temperature have shown that a change in surface roughness affects the deformation mechanism of sliding friction. Static friction of slabs in contact with rubber was also studied in experiments. It is shown that the deformation mechanism of friction in the contact of paving slabs with rubber increases with an increase in the height (Sa, Ssk, Sku) and hybrid (Sdq) roughness parameters. A comparative analysis of friction maps at temperatures from −25 to +60°C was made for samples differing in surface treatment.
On two contact problems for a half-plane with static friction
Authors: Hakobyan V , Hakobyan L , Dashtoyan L
Published: August 2024

Exact solutions of two contact problems are constructed for a half-plane, when a finite number of absolutely rigid flat punches with friction are pressed into the half-plane under the influence of different concentrated loads, and when a periodic system of absolutely rigid flat punches with friction is pressed into the half-plane. It is assumed that friction in contact zones is associated with normal contact pressure by the generalized law of dry friction, in which the coefficient of friction depends on the coordinates of the contacting points of the contacting bodies and is directly proportional to the difference between the coordinates of these points and the coordinates of the middle points of the contact zones. The governing equations of the posed problems were obtained in the form of singular integral equations with variable coefficients relative to the contact pressure and their closed solutions were constructed.
On flexural vibrations of orthotropic strips of variable thickness taken into account of transverse effects with elasticaly built in edges in the presence of axial force
Authors: Gevorgyan G Z , Darbinyan A Z
Published: August 2024

The problem of bending vibrations of orthotropic strips of variable thickness is considered, taking into account transverse effects elastically built in edges in the presence of axial force. The problem was solved using the numerical collocation method. A numerical analysis of the problem was carried out. The problem of Euler stability of orthotropic plate-strips of variable thickness under plane strain conditions is considered, taking into account transverse shear and rotational inertia. The resulting equations make it possible to determine both the frequencies of natural vibrations and the critical values of the axial force at which the plate-strip loses stability. The problems are solved using a modified collocation method under various boundary conditions at the ends and values of geometric and physical parameters characterizing a plate-strip of variable thickness.
Interaction of a bush with a complex internal profile and a coated viscoelastic pipe worn on a rigid cylinder
Authors: Kazakov K E , Parshin D A
Published: August 2024

The present study is devoted to obtaining an analytical solution to the contact problem for a rigid bush and a viscoelastic aging cylindrical coated tube mounted on a rigid shaft or cylinder. A feature of the formulation is the fact that the inner profile of the bush is described by a complex function, which introduces certain difficulties in numerical calculations. The article demonstrates how it is possible to simultaneously take into account both the rheological properties of the layers and the geometric features of the contacting bodies, so that the obtained analytical solution turns out to be effective in real numerical calculations. In the resulting analytical solution, the function describing the inner profile of the bush is included in a separate term. This makes it possible to use a small number of terms of an infinite functional series and at the same time obtain results with high accuracy.
Mechanical properties of aluminum matrix composite reinforced with titanium carbide
Authors: Zemtsova E G , Morozov N F , Semenov B N , Smirnov V M , Venatovskaya L A
Published: August 2024

An original method for the production of metal matrix nanocomposites has been proposed, which consists of depositing carbide structures 4–12 nm thick onto the surface of particles of aluminum powder by molecular layering, mixing the resulting dispersed particles with particles of pure metal in the required concentration, then pressing and sintering the resulting mixture. The resulting workpieces are subjected to intense plastic deformation by high-pressure torsion, which not only significantly reduces porosity, ensures a uniform distribution of reinforcing particles throughout the volume, and destroys carbide shells on the surface of dispersed particles, but also grinds aluminum particles.

Experimental stress-strain curves of the synthesized composites were constructed and the contribution of various hardening mechanisms to the final hardening of the metal matrix composite was assessed.

In metal matrix composites synthesized by this method, with small fractions of the volume content of reinforcing titanium carbide particles (less than 0.1%), almost twofold hardening and a threefold increase in the yield strength are observed with a slight reduction in plastic deformation before failure.
Experimental study of solute diffusion in oscillating flow in a rectangular cell
Authors: Bushueva A , Dyakova V , Polezhaev D
Published: August 2024

The mass transfer of a passive substance dissolved in a fluid in a rectangular Hele–Shaw cell is experimentally studied. We consider mass transfer when the fluid is (i) at rest and (ii) oscillates. In the first case, mass transfer is carried out due to molecular diffusion. The results of measuring the molecular diffusion coefficient of the fluorescent dye Rhodamine B in water are in good agreement with the data obtained by other methods. In the presence of oscillations, the mass transfer rate increases. The comparison of the obtained experimental results with theoretical predictions reveals that the mass transfer is enhanced due to the Taylor dispersion.
Asymptotics of solutions to systems of (pseudo)differential equations with localized right-hand sides
Authors: Dobrokhotov S Yu , Klevin A I , Nazaikinskii V E , Tolchennikov A A
Published: August 2024

The article describes a method for constructing semiclassical asymptotic solutions of multidimensional (pseudo)differential partial differential equations with localized right-hand sides. The method is based on the asymptotic reduction of vector problems (under certain additional conditions) to scalar (pseudo)differential problems, for which efficient asymptotic formulas have recently been constructed. The method is based on the Feynman–Maslov operator calculus. Even if the original problems are stated for differential equations, the operators in reduced problems, as a rule, turn out to be pseudodifferential. Further, nontrivial problems of calculating operator symbols in the reduced scalar problems arise in the reduction process. We discuss approaches to the transformation of these symbols so as to enable their effective use when solving real problems. The method is illustrated by several physical examples.
Peculiarities of icing in a flow with supercooled droplets and ice crystals
Authors: Amelyushkin I A , Kudrov M A , Kuleshov P S
Published: August 2024

New results of aircraft icing are obtained. New mathematical models of physical phenomena are formulated. Original construction of adaptive wing was invented, developed and prototypes were built. New algorithm of aircrafts’ surface with nanorelief are developed. Parametric studies of aircraft icing peculiarities were carried out.
Mathematical modeling of insulating coating of thermal conductivity including body’s own radiation and non-local spatial effects
Authors: Kuvyrkin G N , Savelyeva I Y , Safronov Y A , Sokolov A A
Published: August 2024

In this paper thermal conductivity analysis of insulating coating is discussed. The general partial differential thermal conductivity equation is used with consideration to nonlocal boundary effects. We relying on the Eringen’s approach involves heat-flow vector transformation using nonlocal influence function and weight coefficients. Also presented model includes own surface radiation of the coating.
Mineralogy and Hydrothermal Fluids Characteristics of the Mekarbakti Low Sulfidation Epithermal Gold Prospect at Garut Regency, West Java, Indonesia
Authors: Imawan L , Titisari A D , Setiawan I
Published: August 2024

Mekarbakti prospect is situated in the western sector of Java Island which tectonically lies within the W-E trending Sunda-Banda magmatic arc. This arc hosts numerous prospects for ore mineralization with various types of mineral deposits, one of which is epithermal that found in the study area. The Mekarbakti prospect is located close to the Arinem prospect, about 8 km to the east, which is confirmed as a low sulfidation epithermal deposit type. Arinem is proven to be economical to mine, thus it becomes interesting to conduct study on the Mekarbakti prospect, to elucidate its mineralization model. This paper is dealing with the characteristics of hydrothermal alteration using petrographic and X-Ray Diffraction (XRD) to identify the alteration minerals, using ore microscopy analysis to identify the type of ore minerals, and fluid inclusion to reveal the hydrothermal fluid characteristics. The geological condition of the study area is composed of andesite lava, andesite breccia, tuff, lapilli, and andesite intrusion. The distribution of silicification alteration is controlled by geological structures with an NW-SE pattern, while argillic and propylitic alterations tend to have a gradient trend towards silicification alteration. Propylitic alteration is characterized by chlorite+illite+smectite±epidote. Argilic alteration is marked by the presence of clay minerals such as kaolinite+illite+smectite+quartz. Silicification alteration typified by quartz+kaolinite+diaspore+illite. Ore mineralization in the study area is associated with massive, brecciated, comb, cockade and, stockwork vein textures. Ore and metalliferous minerals are found as pyrite, hematite, goethite, chalcopyrite, sphalerite, galena, pyrrhotite, covellite, chalcocite, acanthite, native gold, and native silver. Generally, the mean homogenization temperature in the research area ranged from 248.05 – 266.12 °C, with salinity ranged from 1.01 – 1.68 wt.% NaCl eq. The epithermal deposit in the study area is classified as deep low sulfidation epithermal deposit specifically in transition between base metal and precious metal interval.
Distribution of Manganese Ore Deposit in Sukaagung Village, Tanggamus Regency, Lampung
Authors: Christin Natalia Happy , Widiyawati  , Jati Widiatama Angga , Naufan Hendrawan Rezki , Ananda Gita Christi Dea , Tri Kemala Arini , Nur Faqih An Nahar Rikza
Published: August 2024

Manganese ore deposits are one of the most widely used metal alloys in everyday life. Generally, manganese ore deposits are present as residual deposits along with iron ore at certain pH and Eh conditions. These deposits can come from the chemical weathering of crystalline schist, limestone, and dolomite rocks or earlier manganese deposits. In Lampung, the presence of manganese ore can be found in Sukaagung Village, Tanggamus Regency, but little research has been done to determine the distribution and potential of manganese ore in this area. Therefore, this study aims to determine manganese ore distribution and enrichment process in the study area using field data and petrography. In general, manganese ore deposits in Sukaagung Village are present as veins that fill fractures and nodules. Manganese ore deposits that were present as fracture fillers were found intersecting marble, quartzite, and mica schist of the Complex of Gunungkasih Tak Terpisahkan, tuffaceous siltstone from Menanga Formation, and the lapilli tuff and andesite of the Hulusimpang Formation. These deposits are present in manganese as botryoidal and dendritic forms in rock fractures. Meanwhile, manganese ore deposits in the form of nodules are present in submarine volcanic sedimentary rocks in the Menanga Formation. The presence of manganese ore deposits in the study area is thought to be the result of the leaching of manganese elements from the banded iron formation which is associated with the Permian-Cretaceous magmatism, hydrothermal submarine, and rift basin. The acidic fluid dissolves other elements and leaves manganese ore as an economical mineral. Manganese ore is then carried by subsurface fluids, filling fractures in Paleozoic-Tertiary rocks. Even though the distribution of manganese ore in Sukaagung Village is quite wide, further research is needed to determine the potential and reserves of manganese ore in the study area.
Preliminary Study of the Graphite Phyllite Rock from the Luk Ulo Melange Complex, Central Java, Indonesia
Authors: Isyqi  , Imam Setiawan Nugroho , Anggara Ferian
Published: August 2024

Phyllite rocks containing graphite minerals are exposed at the Luk Ulo Melange Complex (LUMC), Central Java, Indonesia. This study aims to determine the occurrence, petrographic, and geochemical characteristics of the LUMC phyllite rocks. The method used in this research consists of field observation and laboratory analysis, including petrographic and geochemical analysis using ICP AES/MS. Field observations were carried out in six locations, namely in the Karangsambung, Totogan, Duren, Kebondalem, Kebutuhjurang, and Pesangkalan villages. The phyllites are present as blocks in LUMC with 2 to >10 m in dimension and are associated with other metamorphic rocks such as greenschist, quartzite, and marble. LUMC phyllite rock has a fresh grey-black color, phyllitic foliated structure, and lepidoblastic texture. The main minerals are graphite, muscovite, quartz, and chlorite. Whole rock geochemical analysis was carried out on a phyllite sample from the Karangsambung area and showed that the major elements that dominated were SiO2 (69 wt%), Al2O3 (13 wt%), and Fe2O3 (5.78 wt%) that typical of metapelite rocks.
Effectiveness of silicomanganese smelting utilizing high-ash coal
Authors: Makhambetov Yerbolat , Akhmetov Amankeldy , Myngzhassar Yesmurat , Toleukadyr Ruslan , Burumbayev Azamat , Zhakan Armat , Kutzhanov Magzhan
Published: August 2024

This study investigates the utilization of high-ash coal as an alternative reductant in the smelting of silicomanganese, aiming to reduce the carbon footprint of traditional coke-based processes. Experiments were conducted using an ore-thermal furnace with a transformer power of 200 kVA to simulate industrial conditions. The charge consisted of manganese ore (Mn - 36%), slag from refined ferromanganese production (MnO - 25%), and high-ash coal (ash content 40%–50%). Chemical analysis of the produced alloy showed a composition of Mn–70%, Si–20%, C–1.28%, P–0.06%, and S–0.05%, meeting the standards for silicomanganese. The results demonstrate that high-ash coal can replace coke without compromising the quality of the alloy. This approach not only indirect CO2 emissions but also leverages the abundant availability of high-ash coal, which is often discarded as waste. The study highlights the potential for significant environmental benefits and cost savings, making this method a viable alternative for sustainable industrial practices. The findings support the industrial application of high-ash coal in silicomanganese production, contributing to more eco-friendly and economically feasible metallurgical processes.