bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated Design of Control System for Spaceborne Infrared Imaging Mechanism
Authors: Zhai Yunxuan , Jiu Yuanwei , Chang Xia , Wang Yu , Geng Zhenhua 
Published: May 2023

Abstract
The design method of “centralized acquisition, time-sharing operation and array drive” has been proposed for the integrated and coordinated control of the black-body calibration mechanism, black-body radiation calibration source, focusing mechanism, filter wheel mechanism and thermo-threshold mechanism in an aerospace infrared remote sensor. Compared with the decentralized control of traditional components, this method uses FPGA as the main control chip to effectively realize the integrated function of multi-component control of movable and radiating mechanisms through pulse-width modulation drive control of heater band and semiconductor and servo control of the stepping motor. The independence of the drive array and the stability of the temperature control are verified through experiments, and the feasibility of the design is confirmed. The design reduces the volume, weight and complexity of the product, improves the integration, reliability and versatility of the product, and provides a technical reserve for platform load integration.
MEMS-IMU automatic calibration system design and implementation
Authors: Wang Jingxiao , Liu Ning 
Published: May 2023

Abstract
Aiming at the problems of traditional calibration, long calibration cycles, and low efficiency of traditional error calibration methods for MEMS inertial devices, a MEMS IMU automatic calibration system is proposed. Firstly, the error mechanism of MEMS-IMU is analyzed, the error model is established, and the calibration scheme is designed. Then, the automatic control of the turntable and the automatic data acquisition of MEMS inertial devices are realized by designing the data interaction mechanism between the system equipment. Finally, the least square method is used to identify the model parameters. The experimental results show that this method can meet the requirements of multi-position and multi-rate calibration. After compensation, the relative errors of the MEMS gyroscope and accelerometer are 0.04% and 0.15%, respectively, and the cross-coupling error of the MEMS gyroscope is reduced to about 0.1 °/s. At the same time, the whole calibration process is easy to operate, which greatly shortens the calibration time and improves the calibration efficiency.
Structural design and mechanical analysis for space-borne electronic equipment
Authors: Yin Qifeng , Xue Fei , Shen Li 
Published: May 2023

Abstract
With the development of a new generation of radar performance requirements, the chip integration and module assembly density of onboard electronic equipment have been greatly improved. The integration of the system is becoming more complex. This paper designs a kind of electronic equipment with a superposition structure. Separate functional modules are strung together by a screw. Each module unit has the same sectional size. The conventional cabinet form structure is abandoned. The main contradiction of volume, weight, and reliability is solved well. The mechanical properties of electronic equipment are analyzed by the finite element method, and the structure of the fixed lug is optimized. The result shows that the electronic equipment meets the requirements of structural safety margin. The structural design is safe and reliable.
Kinematic modeling and motion characterization of an articulated mobile robot
Authors: Zhang Tan , Ding Chengjun , Li Xinbao , Zhang Jianing , Xu Yingjie 
Published: May 2023

Abstract
In response to the outstanding problems of poor motion flexibility and poor terrain adaptability of conventional mobile robots in unstructured environments, a multi-vehicle modular articulated mobile robot capable of adapting to complex and variable obstacle terrain was developed by designing and introducing a flexible articulation device. By constructing a kinematic model of the single body module of the robot, integrating the motion constraint relations among the modules, and establishing the overall robot attitude equations, we propose a robot soft motion control method. Based on the analysis of robot motion characteristics under special obstacle terrain, the relationship model between obstacle parameters and robot pose is constructed, and the correction strategy under unilateral unstable motion state is proposed through the analysis of robot motion state under unilateral unstable condition. Theoretical analysis and experimental results show that the robot has good motion flexibility and complex terrain adaptability.
A data-driven approach to fault modeling and diagnosis of brake-by-wire system
Authors: Mei Mingming 
Published: May 2023

Abstract
E-Booster plays an important role in braking safety as the pressure source for vehicle hydraulic systems. According to the design feature of its series controller, the signals on key nodes, which can be directly measured, can be used as the data source for fault diagnosis. In this paper, a deep learning technique of residual 1-D CNN equipped with parallel structure is proposed for fault recognition and classification in a dynamic process. With the help of wavelet transform and probabilistic heat map, it is found that the phase current fault feature is distinct in the frequency domain. In contrast, the uniform demagnetization fault and pressure recession fault are more obvious in the time domain. Therefore, the parallel network structure with a wide and narrow convolutional kernel is used, which can handle multiple complex fault features simultaneously. Simulation models based on both data-driven and mathematical formulations are also established to better fit the actual nonlinear conditions. Finally, the proposed network structure can reach 92.1% classification accuracy compared with the commonly used lightweight 2-D CNN model. It can be concluded that 1-D CNN achieves similar classification results as 2-D CNN with less computational resource consumption.
A search and rescue robot device realization based on ROS operating system combined with visual algorithm
Authors: Cui Jiaqi 
Published: May 2023

Abstract
Aiming at the problem of low accuracy of intelligent devices to find missing people, a search and rescue robot device based on ROS intelligent navigation system was proposed. SolidWorks was used to improve the new mechanical structure that can switch autonomously to different terrain and combined with Yolov5 deep learning algorithm to complete face recognition. Using the stm32 single-chip microcomputer, we adjusted the cascade PID parameters of the motor and simulation to realize the omnidirectional movement control of the robot. Through the analysis and verification of the experimental data, the adaptive ability of the improved robot platform to the terrain was significantly improved. The method can accurately complete the task of face recognition and autonomous navigation, which is practical and improves the accuracy of finding the missing people.
An attitude estimation algorithm for the telescopic arm of the boarding bridge based on YOLOv5 and EPnP
Authors: Chen Weizhuo , Zhang Lijie , Luo Fangrui 
Published: May 2023

Abstract
Aiming at the attitude estimation of the telescopic arm of the boarding bridge in the process of docking with the offshore wind turbine, an attitude estimation algorithm for the telescopic arm of the boarding bridge based on YOLOv5 and EPnP is proposed in this paper. YOLOv5 algorithm is used to detect four marks in the offshore wind turbine logo image, and then the EPnP algorithm is used to solve attitude angles of the telescopic arm relative to the landing port of the offshore wind turbine according to the 2D pixel coordinates of the center point of each mark. The experimental results show that the attitude estimation error of the proposed algorithm is less than 0.4° and the data update frequency of the algorithm implemented in NVIDIA Jetson AGX Xavier is 25Hz, which meets the real-time and accuracy requirements for the attitude detection of the boarding bridge telescopic arm.
Research on High-order Sliding Mode Control Strategy for High Voltage Transmission Line Strip Operation Robot
Authors: Guo Xiyi , Xu Boyu , Zhang Jianfeng , Li Muxuan , Long Jiulong 
Published: May 2023

Abstract
When performing robotic electrical work, the mechanical arm will come into contact with wires, bolts, and gold tools. In order to prevent the robot from being shocked or vibrating excessively during this process, as well as to accurately control the screwing bolt angle issue, the robot force control issue should be taken into account. Based on the theory of higher order sliding mode control for such non-linear systems, a differential observer-based higher order sliding mode control method is proposed in this study. In order to build a type of controller based on the differential observer, the differential observer is used to observe the information of the derivative of the angular velocity and the information of the derivative order sliding variables of the higher-order sliding mode. The outcomes demonstrate the control method’s applicability to powered robots, as well as its ability to successfully suppress the jitter issue associated with conventional sliding mode control and achieve good control performance.
Ripple Voltage Suppression of Dual Active Bridge Converter in Electric Locomotive Using H∞ Loop Shaping Control Method
Authors: He Weiyi , Ma Lei , Cheng Shaokun 
Published: May 2023

Abstract
The next-generation electric locomotive drive system has the problem of double grid frequency ripple voltage in the DC side of a single-phase PWM rectifier. In this paper, the intermediate stage dual-active-bridge DC-DC converter is studied, and an H∞ loop shaping ripple voltage suppression control strategy is proposed to restrain the harmonic voltage and optimize the dynamic and robust performance of the closed-loop system. Firstly, the mathematical model of the DAB closed-loop control system with fluctuating input voltage is established. Then, based on the H∞ loop shaping control theory, the dynamic performance, the ability of ripple voltage suppression, and the robust performance of the system are analyzed in the frequency domain. According to the results, a reasonable compensator is selected to reconstruct the magnitude frequency characteristic curve of the nominal system. After reconstruction, the solution of the robust stability margin of the corrected object is transformed into the H∞ robust control problem under the coprime factor uncertainty. The suboptimal H∞ robust controller is solved to obtain the best robustness boundary of the constructed system. Finally, the H∞ loop shaping ripple voltage suppression controller is obtained by combining the H∞ controller with the compensator. The experimental environment is set up in MATLAB-Simulink software. Compared with the traditional voltage loop control method and the input voltage feedforward control method, the dynamic performance of the proposed control strategy is slightly improved, and while within the allowable robust boundaries of the system, it has better ripple voltage suppression performance. When the system magnitude frequency curve is outside the tolerant robust stability margin, the ripple voltage suppression performance fails, but the harmonic content of output voltage is still far less than the other two control methods. The experiment results also prove the correctness of the theoretical analysis and that the proposed control method is effective and proper.
Impact of leaf phenology on estimates of aboveground biomass density in a deciduous broadleaf forest from simulated GEDI lidar
Authors: Cushman K C , Armston John , Dubayah Ralph , Duncanson Laura , Hancock Steven , Janík David , Král Kamil , Krůček Martin , Minor David M , Tang Hao , Kellner James R 
Published: May 2023

Abstract
The Global Ecosystem Dynamics Investigation (GEDI) is a waveform lidar instrument on the International Space Station used to estimate aboveground biomass density (AGBD) in temperate and tropical forests. Algorithms to predict footprint AGBD from GEDI relative height (RH) metrics were developed from simulated waveforms with leaf-on (growing season) conditions. Leaf-off GEDI data with lower canopy cover are expected to have shorter RH metrics, and are therefore excluded from GEDI’s gridded AGBD products. However, the effects of leaf phenology on RH metric heights, and implications for GEDI footprint AGBD models that can include multiple nonlinear RH predictors, have not been quantified. Here, we test the sensitivity of GEDI data and AGBD predictions to leaf phenology. We simulated GEDI data using high-density drone lidar collected in a temperate mountain forest in the Czech Republic under leaf-off and leaf-on conditions, 51 d apart. We compared simulated GEDI RH metrics and footprint-level AGBD predictions from GEDI Level 4 A models from leaf-off and leaf-on datasets. Mean canopy cover increased by 31% from leaf-off to leaf-on conditions, from 57% to 88%. RH metrics < RH50 were more sensitive to changes in leaf phenology than RH metrics ⩾ RH50. Candidate AGBD models for the deciduous-broadleaf-trees prediction stratum in Europe that were trained using leaf-on measurements exhibited a systematic prediction difference of 0.6%–19% when applied to leaf-off data, as compared to leaf-on predictions. Models with the least systematic prediction difference contained only the highest RH metrics, or contained multiple predictor terms that contained both positive and negative coefficients, such that the difference from systematically shorter leaf-off RH metrics was partially offset among the multiple terms. These results suggest that, with consideration of model choice, leaf-off GEDI data can be suitable for AGBD prediction, which could increase data availability and reduce sampling error in some forests.
The relative role of soil moisture and vapor pressure deficit in affecting the Indian vegetation productivity
Authors: Dubey Nivedita , Ghosh Subimal 
Published: May 2023

Abstract
Atmospheric aridity (vapor pressure deficit, VPD) and soil moisture (SM) deficit limit plant photosynthesis and, thus, affect vegetation carbon uptake. The strong correlation between SM and VPD makes it challenging to delineate their relative contributions to regional vegetation productivity. Addressing this gap is vital to understand the future trajectory of plant productivity in India—the second-highest contributor to global greening. Here, we separate the controls of SM and VPD on the Indian vegetation using statistical and causal analysis. We found that vegetation productivity in India is primarily controlled by SM limitation (87.66% of grids) than VPD limitation (12.34% of grids). Vegetation has a varying association with SM and VPD across different agroecological regions in India. The negative impact of VPD on vegetation carbon uptake is not visible in high-rainfall areas of India. These findings advance our understanding of vegetation dynamics under regional dryness stress and can enhance dynamic vegetation model estimates for India under changing climate scenarios.
Enamel cutting mechanism and performance of different dental burs: an in vitro study
Authors: Zhao Jing , Wu Di , Liu Sinan , Gong Kun , Zhang Zhijun , Zhao Jian 
Published: May 2023

AbstractTooth enamel machining is a common procedure in dental surgery, yet the cutting mechanisms and performance of different dental burs remain unclear. In the dental field, this poses challenges for dentists in selecting appropriate dental burs for specific operations. In the engineering field, this creates difficulties in understanding the cutting mechanisms of tooth enamel and designing new high-performance dental burs. Therefore, the objective of this study is to bridge the gap between medicine and engineering by comprehending the cutting mechanisms and performance of different dental burs for tooth enamel machining. This study established an enamel machining experimental system and utilized the fissure bur, diamond bur, and round bur to conduct enamel drilling and milling experiments on the occlusal, buccal/lingual, and mesial/distal surfaces of the tooth. The results indicate that, compared to the buccal/lingual and mesial/distal surfaces, the milling force is lower (p< 0.05) but the milling temperature is higher (p< 0.05) on the occlusal surface. Furthermore, the fissure bur generated the lowest drilling and milling temperatures (p< 0.05) and the best milling quality. The diamond bur generated the best drilling quality but lacked drilling precision (p< 0.05). The round bur generated the smallest drilling force (p< 0.05) but the largest milling force (p< 0.05). The analysis of the structure and cutting mechanisms of different dental burs on various tooth surfaces explains the aforementioned phenomena. Different dental burs have distinct advantages based on their structures. This study enhances the understanding of tooth enamel cutting mechanisms and dental bur machining performance in the field of medicine and engineering, which can improve the quality of dental surgery and facilitate the development of high-performance dental burs.
Study on plasticized Poly (vinylidene chloride- co- acrylonitrile) polymer electrolytes for battery applications
Authors: Vijaya B , Rani M Usha , Babu Ravi Shanker 
Published: May 2023

AbstractPlasticized Poly (vinylidene chloride- co- acrylonitrile) [P(VdC-co-AN)] polymer electrolytes comprising of Lithium Perchloride (LiClO4) as complexing salt and plasticizers such as Propylene carbonate (PC) andβ-butyrolactone (βbl) is prepared by solution casting technique. Polymer electrolytes were prepared in the ratio [(x)PVdC-co-PAN+(100-x-z) Plasticizer+(z) LiClO4] and were subjected to various characterizations. X-ray Diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were carried out to study the structural and functional groups present in the material. Impedance spectroscopy to find the ionic conductivity of the material. The maximum ionic conductivity at room temperature was exhibited by the samples containing 68% PC (9.237 × 10−4S cm−1) and 66% ofβbl (2.284 × 10−4S cm−1). Samples exhibiting higher ionic conductivity (68% PC and 66% ofβbl) are subjected to Linear sweep voltammetry and transference number measurements. The electrochemical stability is 4.5 v for the both films, whereas transference number is 0.955 and 0.94, respectively. Thermogravimetry/Differential Thermal analysis (TG/DTA) shows the prepared films doesn’t not undergo any weight loss till 220 °C (thermally stable). The surface morphology of the polymer membrane was explored through Atomic force microscopy (AFM).
NCIRF: an organ dose calculator for patients undergoing radiography and fluoroscopy
Authors: Lee Choonsik , Yeom Yeon Soo , Shin Jungwook , Streitmatter Seth W , Kitahara Cari M 
Published: May 2023

Abstract

Background. It is critical to monitor the radiation dose delivered to patients undergoing radiography and fluoroscopy to prevent both acute and potential long-term adverse health effects. Accurate estimation of organ doses is essential to ensuring that radiation dose is maintained As Low As Reasonably Achievable. We developed a graphical user interface-based organ dose calculation tool for pediatric and adult patients undergoing radiography and fluoroscopy examinations. Methods. Our dose calculator follows the four sequential steps. First, the calculator obtains input parameters related to patient age and gender, and x-ray source data. Second, the program creates an input file describing the anatomy and material composition of a phantom, x-ray source, and organ dose scorers for Monte Carlo radiation transport using the user input parameters. Third, a built-in Geant4 module was developed to import the input file and to calculate organ absorbed doses and skeletal fluences through Monte Carlo radiation transport. Lastly, active marrow and endosteum doses are derived from the skeletal fluences and effective dose is calculated from the organ and tissue doses. Following benchmarking with MCNP6, we conducted some benchmarking calculations calculated organ doses for an illustrative cardeiac interventional fluoroscopy and compared the results with those from an existing dose calculator, PCXMC. Results. The graphical user interface-based program was entitled National Cancer Institute dosimetry system for Radiography and Fluoroscopy (NCIRF). Organ doses calculated from NCIRF showed an excellent agreement with those from MCNP6 in the simulation of an illustrative fluoroscopy exam. In the cardiac interventional fluoroscopy exam of the adult male and female phantoms, the lungs received relatively greater doses than any other organs. PCXMC based on stylistic phantoms overall overestimated major organ doses calculated from NCIRF by up to 3.7-fold (active bone marrow). Conclusion. We developed an organ dose calculation tool for pediatric and adult patients undergoing radiography and fluoroscopy examinations. NCIRF could substantially increase the accuracy and efficiency of organ dose estimation in radiography and fluoroscopy exams.
Atomic protein structure refinement using all-atom graph representations and SE(3)-equivariant graph transformer
Authors: Wu Tianqi , Guo Zhiye , Cheng Jianlin 
Published: May 2023

Abstract

Motivation
The state-of-art protein structure prediction methods such as AlphaFold are being widely used to predict structures of uncharacterized proteins in biomedical research. There is a significant need to further improve the quality and nativeness of the predicted structures to enhance their usability. In this work, we develop ATOMRefine, a deep learning-based, end-to-end, all-atom protein structural model refinement method. It uses a SE(3)-equivariant graph transformer network to directly refine protein atomic coordinates in a predicted tertiary structure represented as a molecular graph.

Results
The method is first trained and tested on the structural models in AlphaFoldDB whose experimental structures are known, and then blindly tested on 69 CASP14 regular targets and 7 CASP14 refinement targets. ATOMRefine improves the quality of both backbone atoms and all-atom conformation of the initial structural models generated by AlphaFold. It also performs better than two state-of-the-art refinement methods in multiple evaluation metrics including an all-atom model quality score—the MolProbity score based on the analysis of all-atom contacts, bond length, atom clashes, torsion angles, and side-chain rotamers. As ATOMRefine can refine a protein structure quickly, it provides a viable, fast solution for improving protein geometry and fixing structural errors of predicted structures through direct coordinate refinement.

Availability and implementation
The source code of ATOMRefine is available in the GitHub repository (https://github.com/BioinfoMachineLearning/ATOMRefine). All the required data for training and testing are available at https://doi.org/10.5281/zenodo.6944368.