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Accurate photovoltaic (PV) identification is critical for the effective and healthy development of PV industry. PV recognition is hampered by the complex background and variable shape and color of PV panels in high-resolution remote sensing images. This paper proposes a method for accurately extracting photovoltaic land from high-resolution remote sensing images. The encoder and decoder functions in this network combine multi-layer features to combine rich semantic data. Important spatial and channel properties are captured using the global convolution and the dual attention mechanism, while some lost channel data are recovered using the channel fusion module. The proposed method can effectively solve the problems of photovoltaic panel blurred edges and adhesion. Experiments on open PV datasets show that the IoU of the proposed method in PV01, PV03, and PV08 is 87.02%, 92.98%, and 88.43%, respectively, when compared to U-Net, SegNet, DeepLabv3, and DeepLabv3+. Experimental results show that the proposed method can achieve high accuracy segmentation of photovoltaic panels in high-resolution remote sensing images. [ABSTRACT FROM AUTHOR]

To improve the control accuracy of high power density drive units in supernumerary robotic limbs, a low-speed dead zone adaptive compensation method was proposed. Firstly, the drive unit model was established based on the least square system identification and damping identification methods. Then, a computed torque control method for the drive units was proposed. Finally, an adaptive compensation method for the low-speed dead zone of the drive units was proposed and verified. The experimental results show that compared with the traditional PID control method, the maximum angle tracking errors of the drive units are reduced by about 53 % and the average angle tracking errors are reduced by about 38% after the computed torque control method is utilized. Based on the computed torque control method, the maximum angle tracking errors of the drive units are reduced by about 45% and the average angle tracking errors are reduced by about 60% after the low-speed dead zone adaptive compensation method is adopted. The control accuracy of the drive units is significantly improved. [ABSTRACT FROM AUTHOR]

[Objective] Working at the maximum power point of photovoltaic cells can improve energy utilization efficiency and ensure sufficient power supply. However, most distributed photovoltaic power generation systems are located in natural environments, and the nonlinear changes in the environment in which photovoltaic panels operate make it very difficult to maintain their maximum power point. Traditional maximum power point tracking methods, such as perturbation observation, conductance increment, and particle swarm optimization, yield unsatisfactory results because of their different shortcomings. [Methods] To address the problem of maximum power point tracking in photovoltaics, this paper proposes a maximum power point tracking (MPPT) method for photovoltaics through research on neural network technology and is based on an extreme learning machine (ELM) neural network controller optimized using the sparrow search algorithm (SSA). Herein, a training database is established by analyzing and collecting data on the maximum power curve of photovoltaic cells at different temperatures and light intensities. The proposed neural network controller is trained to form a two-input and one-output controller. The voltage value corresponding to the maximum power point is calculated in real time based on the collected temperature and light intensity data and transmitted to the subsequent boost converter circuit controller. Further, a modulated wave is generated through PWM modulation, which controls the output voltage of the boost converter circuit to track the maximum power point voltage and builds a simulation experimental platform using MATLAB/Simulink. [Results] The simulation results show the following: 1 the proposed method has a high calculation speed and can rapidly track the reference voltage value, making the voltage value accurate. 2 The proposed method directly controls the voltage changes without oscillation or overshoot, resulting in a stable system. 3 The proposed method shows good search accuracy, convergence speed, and stability. The performance of the other three aforementioned mainstream tracking methods and the output voltage of the proposed method under sudden increase or decrease in light intensity are analyzed. [Conclusions] The results indicate that the proposed method can rapidly achieve maximum power point tracking without oscillation and overshoot issues. Compared with the traditional methods, the proposed method performs better in terms of search accuracy, convergence speed, and stability. [ABSTRACT FROM AUTHOR]

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When the photovoltaic module is partially shaded, the problems of false tracking, slow tracking speed and low output power usually appear in the process of maximum power point tracking (MPPT). To make the maximum power output process of photovoltaic modules fast, stable and accurate under partial shading condition, a composite MPPT algorithm (INC-GCA) was proposed based on incremental conductivity algorithm (INC) and global comparison algorithm (GCA). To verify the algorithm, a Simulink simulation model was built, and a photovoltaic experimental platform was designed. The results show that when the photovoltaic module is partially shaded, the composite algorithm based on INC algorithm and GCA can accurately track the maximum power with fast tracking speed and high reliability, and the problem of false tracking is completely avoided. Compared with the incremental conductance method, the proposed algorithm can effectively improve the power generation efficiency of the photovoltaic system and improve the economic benefits of the photovoltaic power station. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the vibration control effects of floating rail fasteners on the metro depot and its over-track buildings, a metro depot and its over-track buildings are selected for field test and the track-stratum-operation depot-platform coupling finite element calculation model is established and verified by the measured vibration response data. The track-stratum-operation depot-platform-buildings coupling large-scale dynamic finite element analysis model is established based on the extension of the former, and the reaction forces of ordinary fasteners and floating rail fasteners are input into the model respectively to solve the vibration responses of the over-track buildings and analyze the insertion loss of vibration level varying with frequency and maximum Z vibration level in order that the effects of floating rail fasteners on the vibration control of the over-track buildings are evaluated. The research shows that for the building forms studied in this paper, the significant vibration frequency of building floor is 31. 5 Hz when the vibration propagates to the over-track buildings through the depot and the over-track platform. The floating rail fastener has few obvious effects on vibration control at the vibration significant frequency 31. 5 Hz of this over-track buildings, mainly because its stable vibration reduction frequency band occurs above 31.5 Hz. The control effects are optimal near 63 Hz, and the maximum vibration reduction of 15 dB can be achieved. With the floating rail fasteners, the maximum Z vibration level of the over-track building floor generally decreases by 2-5 dB. The research results of this paper can provide reference and basis for the selection and design of damping track for the vibration control of the depot and over-track buildings. [ABSTRACT FROM AUTHOR]

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Road marking is an indispensable part of road traffic safety. In order to clarify the performance attenuation law of the water-borne road marking, indoor simulated aging conditions and substantial project tracking monitoring were conducted to analyze the influence of different aging cycles and different loads on the abrasion value of water-borne markings, and the coefficient of retroreflected luminance were fitted to study the performance attenuation behavior of water-borne road marking abrasion resistance and coefficient of retroreflected luminance. The result showed that oxidation and water damage mainly occurred in water-borne road marking under ultraviolet aging. When the aging cycle was from 0 to 20 cycles, the abrasion value of the water-borne marking changed little, ranging from 0. 9 to 5. 8 mg. After 20 cycles, with the increase of the aging cycle, the increase of the abrasion value of the water-borne marking gradually became faster, and the abrasion value reached 21. 5 mg at 40 cycles. The coefficient of retroreflected luminance of the water-borne marking decreased continuously with the extension of service time. The decrease rate of the coefficient of retroreflected luminance was slow in the initial stage and became faster with the extension of service time, and it was consistent with the decay law of abrasion resistance in indoor simulated aging process. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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: Solar tracking technology has been widely used in large power stations, photovoltaic agriculture, and green building industry. Among them, hybrid tracking can be expected to consider both photoelectric and solar trajectory tracking. However, it is still lacking in the accurate evaluation of different weather conditions, due to the excessively broad control criterion in the solar hybrid tracking using light intensity, and the vague conditions for the weather identification. In this research, a solar hybrid tracking system was designed under complex weather conditions. Moreover, a multi-threshold control criterion was proposed to divide the weather conditions. The tracking characteristics of the system were analyzed under different tracking strategies in the concentrated and non-concentrated environments, combined with the weather conditions. The control criterion was classified into irradiance fluctuation, high irradiance, low and extremely low irradiance weather. As such, the photoelectric and solar trajectory tracking automatically adjusted, or fixed the inclination angle, according to the external weather changes. Firstly, the prototype of a hybrid tracking system was developed for solar power generation. Specifically, the Raspberry Pi 4B controlled by Node-RED was used as the control core, and the signal was divided by the analog switch of CD4052. At the same time, the photoelectric tracking signal and the fixed inclination angle placement signal were outputted by Arduino, whereas, the tracking signal of the solar trajectory was outputted by STM32F407. Three-way parallel control was adopted to avoid interference with each other in the different control strategies. Secondly, a series of tracking tests were carried out to determine the foundation for the switching of the tracking system under concentrated and non-concentrated light conditions. The switching criteria were summarized for the hybrid tracking system since the tracking performance of the system varied depending on the weather and the tracking mode. The irradiance and power generation curves were also determined that the system received under various tracking strategies. A hybrid tracking scheme was developed to investigate the influence of weather on irradiance characteristics, in order to keep tracking the temperature change of battery panels. The irradiance and temperature curves demonstrated that the irradiance was the primary determinant of the variance in PV cell output, while the temperature remained constant. As a result, the hybrid tracking system can be expected to track the high irradiance for higher power production. Finally, the tracking prototype was tested to verify the impact of the criterion program on the hybrid tracking system. The test results showed that the average power generation of a no-concentrated hybrid tracking system on a sunny day was 0.03 and 0.16 W higher than that of photoelectric and solar trajectory tracking. Additionally, the average power generation of the concentrated hybrid tracking system on a sunny day was 0.81, which was 0.03 and 0.55 W higher than that of photoelectric and solar trajectory tracking. Anyway, the experiment verified the feasibility of the developed device. The new criterion can also provide a promising idea for hybrid tracking technology under complex weather. [ABSTRACT FROM AUTHOR]

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Peanut harvesting has posed a great promise for the sustainable development in modern agriculture. This study aims to improve the path-tracking accuracy of an unmanned crawler-mounted peanut harvester on sandy land. 4HBL-2 self-propelled peanut combine harvester was taken as the research object. A systematic investigation was also carried out on the unmanned path-tracking control of the crawler-mounted harvester. The optimal relationship was established between the kinematic model of the crawler-mounted harvester and the virtual steering angle function. The course deviation was used as the observation value, whereas, the angular velocity calculated by the Ackerman model was used as the measurement value. Kalman Fusion Algorithm was also designed to obtain the virtual steering angle using the Ackerman model. The PID path tracking was improved significantly, according to the virtual steering angle. A double PID path tracking control was proposed using preview tracking. A pulse width controller was then selected to realize the accurate path-tracking control of the crawler-mounted peanut harvester. The simulation results show that a control stage of 4° was used to more smoothly perform the steering action in the control system. There was no change in the signal period and waveform distortion. A series of field experiments show that the average absolute error and the maximum deviation of the linear tracking were 2.23, and 4.14 cm, respectively, when the peanut harvester was operated at a speed of 0.6 m/s in the sand. The performance of the improved system was enhanced by 56.12%, and 66.07%, respectively, compared with the PID path tracking controller. The path tracking experiments showed that the response duration values of the control system were 11.00, 12.92, and 13.78 s, respectively, while the corresponding distances were 6.60, 7.75, and 8.26 m, respectively, when the initial deviation was 0.5, 1.0, and 1.5 m, respectively. Specifically, the maximum overshoot was 5.68, 5.84, and 6.09cm, respectively. The tracking path distance was reduced by 1.92%, 4.43%, and 8.71%, respectively, whereas, the overshoot was reduced by 8.45%, 17.56%, and 5.17%, respectively, compared with the wheeled harvesters. The maximum deviation and average absolute error of the peanut harvester were 5.87 and 2.72 cm, respectively. The ratios of deviation within ±5 cm and ±10 cm were 97.11%, and 100%, respectively. The general technical conditions were also compared for the post-installation of the satellite navigation automatic driving system of agricultural machinery in the industry standard. The connection performance of the crawler peanut harvester can be expected to meet the high requirements of the connection performance. The path tracking control accuracy of the crawler-mounted peanut harvester can also fully meet the harsh requirements of unmanned operation in sandy land. [ABSTRACT FROM AUTHOR]

SiC MOSFET devices have the characteristics of high switching frequency, low loss, and high temperature resistance, which can significantly improve the power density and efficiency when used in wireless charging. However, in the control of the wireless charging converter, hard turn-on and hard turn-off are easy to occur, which will generate additional switching losses. At the same time, under the influence of the electromagnetic environment and parasitic parameters, the gate stage of the switch tube is prone to accelerated aging or damage due to voltage overshoot and oscillation. Based on the above reasons, the switching characteristics, switching losses and factors affecting the reliability of the switch in the bidirectional wireless charging system were analyzed and verified by simulation. Finally, through the comparison experiment of different driving parameters at the full power and half power point of the built bidirectional wireless system, prototype the change trend of driving parameters on system transmission efficiency and gate-level waveform was obtained, which has a certain reference for the application and efficiency optimization of SiCMOSFET in bidirectional wireless charging system. [ABSTRACT FROM AUTHOR]

The no-idle flow shop problem (NIFSP) is a typical NP-hard problem with constraints in the flowshop problem. In most real-world scenarios, the no-idle constraint is the basic requirement for the machine. However, the current proposed algorithms on the NIFSP problem have poor flexibility in comprehensive performance and parameter adjustment, for large-scale instances. To this end, this paper proposed an variable block internal iteration algorithm named VIIA with the goal of minimizing the maximum make span. In the initialization phase of VIIA, used the improved FRB5 produced the initial solutions, which improved the efficiency of FRB5, and greatly reduced the CPU consumption time while ensuring the algorithm performance. In the destruction reconstruction phase, it increased the internal iteration of the number of removed variable blocks, thus flexibly adjusted the parameter values. VIIA increased the neigh borhood search to adapted to different size of instances. In order to verify the performance of VIIA, the algorithm was compared with several algorithms that perform well in the flowshop scheduling problem. The experimental results demonstrate the superiority of VIIA in solving the NIFSP problem, and the performance of VIIA is obviously better than that of the comparison algorithms in the search of the optimal solution. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A large number of photovoltaic grid-connected operation will cause the decline of system frequency response performance, and the identification of system time-varying inertia is helpful for photovoltaic to participate in the setting of frequency regulation parameters. In view of this, an optimization strategy of photovoltaic frequency regulation control parameters was proposed by identifying the equivalent inertia and damping. Firstly, based on the equivalent model of photovoltaic grid connected system, the prediction error method (PEM） was used to identify the equivalent inertia and damping of the system. Then, the state space prediction model of frequency response of photovoltaic grid connected system was further established, and the parameters of primary frequency modulation coefficient and virtual inertia coefficient of photovoltaic frequency modulation control were optimized to ensure that the equivalent inertia and damping of the system meet the requirements of system frequency modulation. Finallly, the simulation model of three machines and nine nodes standard system was built based on Matlab/Simulink. The simulation results show that the proposed method can effectively improve the frequency characteristics of photovoltaic grid-connected system and improve the flexibility of photovoltaic frequency regulation, so that the lowest frequency and the maximum frequency change rate increase by 0.1 Hz and decrease by about 50% compared with the traditional primary frequency regulation [ABSTRACT FROM AUTHOR]

In traditional VSG control, the introduction of the inertia moment and damping coefficient of the synchronous generator into the photovoltaic inverter will result in poor dynamic adjustment capabilities of the photovoltaic grid-connected system. In view of this problem, this study proposes an improved VSG control strategy. The relationship between power angle and active power and the transient process of the rotor angular frequency oscillation period are discussed through the mathematical model of the converter. The principles for selecting moment of inertia and damping coefficient are given, and the rate of change of moment of inertia and angular frequency as well as damping coefficient and angular frequency are analyzed. The relationship between the changes leads to the improvement strategy of photovoltaic grid-connected under the control of adaptive VSG. The simulation results show that the photovoltaic grid-connected system based on the adaptive VSG control strategy has a good dynamic response, which proves the effectiveness and superiority of the improved strategy. [ABSTRACT FROM AUTHOR]

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The pore size controllable mesoporous activated carbon was prepared by an environmentally friendly water vapor activation method using agricultural solid waste hemp stem as raw material, and it was used as an adsorbent to remove the dye methyl orange (MO) from simulated wastewater・ The effects of activation temperature, initial concentration of MO, initial pH value and reaction time on the structure and the adsorption of the hemp stem-based mesoporous activated carbon were investigated・ The results showed that the hemp stem-based mesoporous activated carbon HMAC800 prepared at 800 °C had a specific surface area of 1 436 ・ 5 m2/g, rich and homogeneous mesopores (〜3 nm) and a mesopore volume of 1 ・ 71 cm3/g, and its surface was rich in oxygen-containing functional groups, which was helpful for the adsorption of the large molecule dye MO; The equilibrium adsorption capacity could reach 487 mg/g under the optimal adsorption cond让ions of 25 °C, initial concentration of 100 mg/L of MO, HMAC800 dosage of 10 mg, pH 7, adsorption time of 120 min, and the removal efficiency was close to 100%, and the adsorption process of HMAC800 on MO was in accordance w让h the pseudo・second-order model; the maximum adsorption capacity of HMAC800 was up to 769 ・ 2 mg/g, and the adsorption isotherm was in accordance with the Langmuir model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: The airborne laser bathymetry system transmitted laser pulse through the complex channel which consisted of atmosphere, air⁃sea interface and water channel. The signal power decreased exponential with the increment of the water depth, and the pulse waveform was stretched and distorted at the same time. These two types of transmission characteristics would limit the maximum detection depth and the measurement accuracy of depth, respectively.Methods: The purpose of the proposed algorithm is to improve the measurement accuracy of laser bathymetry system on the premise of ensuring the maximum detection depth performance. First, the water quality and Monte Carlo simulation method are used to study the different depth of echo signal characteristics. It reveals the propagation properties of laser signal and establishes a new parameter design method for laser bathymetry system, which can meet the requirment of inter⁃ national airborne laser depth bathymetry system. Then, the waveform distortion of echo signals at different depths are simulated under the specific system parameters. The adaptive matching filter algorithm is de⁃ signed to improve the measurement precision.Results: The simulation results revealed that the designed system parameters and the adaptive matched filtering algorithm can achieve the performance with the maximum detection depth of 50 m with measurement accuracy of 166 mm in the daytime and with the maximum detection depth of 70 m with measurement accuracy of 172 mm at night for laser bathymetry system. Conclusions:The results show that the adaptive matched filtering algorithm can improve the measurement accuracy and serve the marine surveying and mapping of China. [ABSTRACT FROM AUTHOR]