bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Improved Vibe Algorithm to Detect Personnel Underground in Coal Mines
Authors: Hao Bonan , Zhang Liya , Peng Ran 
Published: September 2021

Abstract
Coal mine safety has always been the most important prerequisite for underground coal mine work. Mine personnel inspection is an effective means to ensure underground safety production. Therefore, the quality of inspection will play a decisive role in safety production. At present, due to the influence of the complex environment in coal mines, ghost images are prone to appear in the process of personnel detection, which has a certain impact on the accuracy of detection. Aiming at this phenomenon, a Vibe method for secondary detection based on ghost images is proposed. In the process of underground coal mine personnel detection, the minimum bounding rectangle of the personnel area is delineated, and each pixel of the personnel area and all the areas outside the rectangle are calculated separately. The process of judging whether it is a ghost image and eliminating the ghost image by the number of pixels whose similarity reaches the threshold. Through subjective and objective verification, the proposed improved algorithm has been effectively improved compared to the traditional Vibe algorithm and the Vibe+ algorithm, which is prone to ghosting problems. In terms of the accuracy, recall rate, F1 value and other objective evaluation indicators of the algorithm model, it is proposed Compared with the two algorithms, the improved Vibe algorithm improves by 2.71%, 4.79%, and 3.73% respectively. Experimental data shows that the improved Vibe algorithm effectively suppresses the appearance of ghosts in the process of underground coal mine personnel detection, improves the accuracy of foreground and background separation, enhances the ability to detect moving targets in coal mines, and provides technical support for safe production in coal mines.
DeepGCNs-Att for Point Cloud Semantic Segmentation
Authors: Wang Xinyu , Jiang Bin , Zhang Ziheng , Tong Cheng , Me Qing , Xiao Jian , Tong Yi 
Published: September 2021

Abstract
Compared with traditional CNNs, Graph Convolutional Networks (GCNs), with the graph’s neural network structure, can better characterize non-Euclidean space. Furthermore, with the number of the network layers increasing, deep GCNs demonstrate outstanding performance in mining the partial relationship between the point cloud’s local features. However, the current deep GCNs algorithm cannot sufficiently exploit the point cloud’s global characteristics for semantic segmentation. This paper proposes a novel network structure called DeepGCNs-Att to efficiently aggregate global context features. Moreover, to speed up the computation, we add an Attention layer after the GCN Backbone Block to mutually enhance the connection between the distant points of the non-Euclidean space. Our model is tested on the standard benchmark S3DIS. By comparing with other deep GCNs algorithms, our DeepGCNs-Att’s mIoU has at least two per cent higher than that of other models and even shows excellent results in space complexity and computational complexity under the same number of GCN layers.
HybridKV: An Efficient Key-Value Store with HybridTree Index Structure Based on Non-Volatile Memory
Authors: Ding Chen , Wan Jiguang , Yan Rui 
Published: September 2021

Abstract
Non-Volatile Memory (NVM) is a new type of storage media with non-volatile data, higher storage density, better performance and concurrency. Persistent key-value stores designed for earlier storage devices, using Log-Structured Merge Tree (LSM-Tree), have serious read-write amplification problem and do not take full advantage of these new devices. Existing works on NVM index structure are mostly based on Radix-Tree or B+-Tree, index structure based on Radix-Tree has better performance but takes up more space. In this paper, we present a new index structure named HybridTree on NVM. HybridTree combines the characteristics of Radix-Tree and B+-Tree. The upper layer is composed of prefix index nodes similar to Radix-Tree, which is indexed by the key prefix speed up data locating, and providing multi-thread support. The lower layer consists of variable-length adaptive B+-Tree nodes organizing key-value data to reduce space waste caused by node sparseness. We evaluate HybridTree on a real NVM devices (Inter Optane DC Persistent Memory). Evaluation results show that HybridTree’s random write performance is 1.2x to 1.62x compared to Fast & Fair and 1.11x to 1.52x compared to NV-Tree, with 54% space utilization reduced compared to WORT. We further integrate HybridTree into LevelDB to build a high performance key-value store HybridKV. By storing HybridTree directly on NVM, the problem of read and write amplification of LSM-Tree is avoided. We evaluate HybridKV on a hybrid DRAM/NVM systems, according to the results, HybridKV can improve random write performance by 7.5x compared to LevelDB and 3.23x compared to RocksDB. In addition, the random read performance of HybridKV is 7x compared to NoveLSM.
Simulation study on transformer inrush current and its suppression
Authors: Wang Lifang , Liu Ren , Huang Yue , Li Yangqing , wang Yan 
Published: September 2021

Abstract
When no-load closing or the voltage recovers after external fault removal of transformer, the inrush current will be caused due to the saturation of iron core, which may lead to misoperation of relay protection device, overvoltage and damage of equipment insulation. It is necessary to find a method to restrain the inrush current harm of transformer. In this paper, Matlab / PSB is used to simulate the inrush current of three-phase transformer under the conditions of no-load switching on and external fault removal, and the simulation research is carried out by changing the switching angle method and changing the transformer connection group method to suppress the inrush current of transformer. The simulation results show that the simulation of inrush current and its suppression can be realized effectively by using Matlab / PSB, which provides the basis for the research of transformer protection algorithm.
Internal force – deformation and corresponding control measures of shield tunnel with a 5.8m diameter under lateral pressure loss conditions
Authors: Peng Hongxia , Zheng Qiang , Zhang Wenlong , Zhang Xiaohui 
Published: September 2021

Abstract
In consideration of the deformation reservation, treatment and repair of the shield tunnel structure in the 100-year service life, the designed inner diameter of the shield tunnel structure tends to increase. However, the increase in the diameter will reduce the overall stiffness of the structure and reduce the shield tunnel’s mechanical properties under load changing conditions. Taking the 5.8m-inner-diameter shield tunnel in Nanjing as an example, this paper establishes a refined three-dimensional numerical model of the shield tunnel and validates the model with the results from a full-scale experimental test. Mechanical responses of the shield tunnel under the influence of the surrounding engineering activities are analyzed, and the structural maintenance and deformation control strategy are also discussed. The research shows that as the lateral pressure coefficient decreases (i.e. when unloading occurs around the tunnel structure), the stress and deformation curves of the structure have a strong nonlinear characteristic: when the lateral earth pressure loss is about 0% to 21%, the structure is in a near-elastic state, and the deformation and internal force response are not sensitive to load-changing conditions; when the lateral earth pressure loss is 21%∼43%, the damage, stress and deformation of the tunnel structure will increase rapidly, indicating that the structure is in the stage of plasticity, which is the critical interval for structural maintenance; when the lateral pressure loss exceeds 43%, the structure reaches total yielding stage. Therefore, the corresponding maintenance and control measures of shield tunnel segment structure are proposed from the aspects of prevention at the source, control in the process and treatment at the end.
Research on optimization of power grid range and pre-control strategy of power flow in key areas under ty-phoon weather
Authors: Chen Jianfu , Qiu Guanxin , Gan Deshu , Zhang Yong , Wang Yaling , Wu Haixiong , Sun Diankun , Deng Changhong , Huang Wentao 
Published: September 2021

Abstract
Typhoons Typhoons are extremely destructive and the route trajectory is ex-tremely uncertain. The power grids in coastal areas are frequently attacked by typhoons, resulting in large-scale power outages. When a typhoon strikes, it is difficult to determine the trajectory, which may cause simultaneous fail-ures of multiple contact lines at the same time and the location of the failure is difficult to predict in advance. Based on the above background, this paper proposes a strategy for optimizing the power supply range of the power grid in key areas and pre-controlling the power flow under typhoon weather. First of all, this article will optimize the scope of key areas. The minimum overhead cable ratio, the optimal generator load capacity ratio and the minimum connection sec-tion power flow between the key area power grid and the external power grid are used as the optimization objective function, and the cuckoo search algo-rithm is used to supply power. Scope is optimized. Based on the above opti-mization results of the power supply range, a power flow pre-control strategy is proposed to ensure that the power flow of the connection section between the power grid in key areas and external power grids is zero by optimizing the output of generators, energy storage equipment, and load shedding, and finally ensure that the key areas under typhoon mode the grid can transition and operate stably.
The design of special energy conversion device of integrated self-powered brake system
Authors: Qiao Weizhi , Li Ding-bo , Gao Xiang , Liu Xiaochao , Zhang Hao , Li Renjie , Wang Xiyu , Hou Yanze , Chen Chong 
Published: September 2021

Abstract
In recent years, a novel electro-hydraulic integrated self-powered brake system for aircraft has been proposed. A modular “self-powered device” is installed near the wheel to recover the rotational kinetic energy when the wheel lands and convert it into hydraulic energy for braking. The energy conversion device is the compact high-power-weight ratio energy harvesting mechanism, which needs to be designed in the extremely narrow internal space of the wheel. At the same time to ensure high reliability, high strength, high power weight ratio, difficult, and wheel brake disc internal temperature reaches 600 °C above, this to the design of the can take institutions are challenges. In this paper, the high strength compact high power-weight ratio energy conversion device as the research goal, through new principles, new structure, new materials, new technology, new methods and other means of the energy taking mechanism design and development, and finally achieve the strength, stiffness, reliability, life of the energy conversion device to meet the requirements of the system.
PSO-PID control strategy for ship anti roll slider device under the influence of long peak wave seas
Authors: Liu Rui , Xiang ZuQuan , Wang YaBin , Li Fei 
Published: September 2021

Abstract
The ship will produce various swaying motions after being affected by wind, waves and other disturbing factors when sailing. among which the transverse swaying motion is the most violent. By the effective control of transverse swaying motion it can improve the safety of ship sailing and the comfort of crew. Thus, in the present study, ship anti roll slider device is chosen as the research subject, and a theoretical analysis on the principle of rocking reduction of ship anti roll slider device is performed. For the problem that the PID controller parameters do not have self-tuning capability, the PID controller parameters are optimized by introducing the PSO algorithm, and the PSO-PID controller is designed on this basis. The PID controller and PSO-PID controller are used to simulate the ship anti roll slider device on Matlab. and the simulation results show that the PSO-PID controller has good rocking reduction effect under different sea conditions, which verifies the effectiveness and superiority of the PSO-PID controller.
Identification Method of Moment of Inertia with the Observed Angular Velocity Containing Gauss White Noise
Authors: Zhao Guangjiu , Zhou Heng , Sheng Tao 
Published: September 2021

Abstract
The identification of the mass characteristic parameters of the spacecraft plays a vital role in improving the accuracy of the spacecraft control system. Due to the limit of sensor accuracy, there exists so much noise in the measurement angular velocity data, which causes great challenge of parameter identification. In order to solve the problem of identification of the spacecraft’s moment of inertia, a new filter-identification method is proposed, which combines the square root volume Kalman filter and the recursive least square. Firstly, the filter method is used to remove the Gaussian white noise in the measurement equation and then the recursive least square method is used to calculate inertia of moment to deal with filtered data. The above steps continue to iterate until the results converge. The simulation results show that, compared with the identification result directly calculated by the recursive least square method, the identification accuracy of filter-identification method is improved by a half, which means this method is of great significance for enhancing the control accuracy and robustness of the spacecraft control system.
Design of Intelligent Sonar Array Placement System Based on MCU
Authors: Zhang J.Y. 
Published: September 2021

Abstract
Aiming at the problem that the existing sonar array placement methods are not intelligent and rely heavily on human resources, a remote Array Placement System Based on ATmega2560 microcontroller is designed to place the array remotely and accurately through the remote controller. This design can promote the Unmanned degree and accurate operation of Sonar array placement.
Research on the Planning Method of Robot Terminal Speed Based on Task Characteristics
Authors: Jiang Benchi , Zhan Qingrong , Li Jiankang , Duan Pengfei , Du Xin 
Published: September 2021

Abstract
In order to study the speed planning of the industrial robots trajectory end under different tasks, the three speed planning methods of the third degree polynomial, the fifth degree polynomial and the five-segment S-curve are compared and studied. Analyze the stability and positioning accuracy of the robot’s end motion process in different occasions, and combine the speed and acceleration changes of the three speed planning methods, and recommend the end speed planning method for common tasks such as palletizing, loading and unloading, and grinding. Taking specific tasks as an example, the simulation results verify the rationality of the recommended method.
Construction and analysis of assembly 3D deviation model considering part tolerance and deformation
Authors: Wang Yunlong , Yuan Bo , Zhang Chao , Mu Xiaokai , Sun Qingchao , Sun Wei , Liu Chong 
Published: September 2021

Abstract
The existing assembly precision design mainly uses the tolerance and fit to control the geometric accuracy, and does not accurately grasp the influence of part deformation on assembly performance. In this study, a design theory and method for flexible body assembly is proposed, which considers the factors of tolerance and deformation. Firstly, based on the spatial multi-body kinematics, a reasonable modeling method of 3D tolerance of part surface suitable for product design process are given; Secondly, the deformation geometric features are calculated, and the 3D tolerance mathematical model including the part deformation is obtained by combining with the 3D tolerance modeling method; Finally, taking an engineering example as the research object, a 3D assembly deviation mathematical model including part deformation is constructed. The analysis results show that the cumulative deviation at the end of the system has a great influence on the z-direction precision in the system space, and the error is -0.028 mm. Therefore, the influence of part deformation deviation on assembly performance should be fully considered in the process of mechanical system assembly design. This research provides a theoretical basis for further research on precision prediction, simulation and control methods of mechanical system.
Numerical simulation of supercritical CO2 characteristics in a double-pipe microchannel gas cooler
Authors: Yang D , Wang N , Xie J 
Published: September 2021

Abstract
In this paper, numerical simulation is considered as a method to explore the heat transfer characteristics of sCO2 under different pressures, CO2 mass flow and CO2 inlet temperature in the double-pipe microchannel heat exchanger. 0.89 mm was adopted as the microchannel diameter. No matter it is under different pressures, different CO2 mass fluxes or different inlet temperatures. The heat transfer coefficient of supercritical CO2 rises sharply to the highest point and then falls slowly. The maximum value of the heat transfer coefficient of CO2 always appears at the position where Tb<Tpc with all working conditions. Lower pressure, CO2 mass flux and CO2 inlet temperature lead to higher heat transfer coefficient. No matter what kind of working conditions, CO2 has not been cooled to water temperature.
Research and Development of Energy Consumption Monitoring and Operation System for Campus Training Equipment
Authors: Chen Shuaihua 
Published: September 2021

Abstract
With the vigorous development of education in China, the energy consumption of campus training equipment, as a microcosm of social energy consumption, has attracted more and more social attention. The traditional energy consumption meter reading measurement method has been difficult to meet the requirements of energy-saving campus construction in colleges and universities because of its low efficiency and poor accuracy. Taking the energy consumption monitoring construction project of training equipment in a school as an example, this paper studies the system architecture and scheme design of energy consumption monitoring platform construction based on Internet of things technology and cloud platform technology. The scheme realizes the functions of real-time monitoring, statistical analysis, energy consumption early warning, quota management and so on, so as to realize the cloud management of electrical safety hazards.
Underwater Target Detection Based on Deep Neural Network and Image Enhancement
Authors: Zheng Yunliang , Yu Mengxue , Ma Zi’ao , Liu Rong , Liu Yang 
Published: September 2021

Abstract
Underwater target detection tasks refer to the detection of targets contained in underwater images. Unlike traditional target detection tasks, for underwater targets, due to factors such as illumination, camera shake, complex background interference, and diversification of target types, the effect of target detection will be affected. In this paper, we propose a target detection algorithm based on image enhancement and deep network. The algorithm first enhances the image data to obtain a better contrast, and then uses a deep learning algorithm to separate the target and the background to improve the detection performance of the target. Experimental results show that the algorithm can achieve better detection performance.
Study on the film-forming ability of water in oil emulsion with water concentration
Authors: Zhang Lu , Chen Lu , Wang Wen 
Published: September 2021

Abstract
This paper mainly explores the influence of different loads on the lubrication performance of point contact under pure rolling conditions and the abrasion phenomenon of water-containing emulsion on the contact area under pure sliding condition. The laboratory apparatus is point contact lubrication friction test equipment and the lubricant is water-containing emulsion.
Plasma treatment for enhancement of the sorption capacity of carbon fabric
Authors: ZADIRIEV Ilya , KRALKINA Elena , SAMOILOV Vladimir , ELCHANINOVA Victoria , GORINA Valentina , IVANENKO Ilya , VAVILIN Konstantin , NIKONOV Alexander 
Published: September 2021

Abstract
In this work we carried out an experimental investigation into enhancement of the sorption capacity of carbon fabric using plasma treatment methods. Carbon fabric is based on viscose fiber and is hydrophobic by nature. Enhancement of the fabric sorption capacity is required for its application in medicine. For this purpose, two plasma treatment methods were considered, i.e. atmospheric nonequilibrium radiofrequency (RF) discharge and a vacuum RF plasma source with an external magnetic field. Samples treated by atmospheric discharge demonstrated aging effects during the first week after treatment. The sorption capacity of samples treated by the RF plasma source was stable over the same period and reached values as high as 0.95. Parameters of the beam created by the vacuum RF plasma source were analyzed and dependences of the fabric sorption capacity and specific surface area on plasma treatment time were investigated. We found that sorption capacity reached its maximum value after 30 min of treatment and did not change significantly if processing was continued, while the specific surface area reached its maximum after 3 min of treatment and quickly decreased after that. It was found that the micropore structure of the fabric remained almost the same during plasma treatment. The volume of mesopores in a unit of the fabric mass (specific volume) doubled during the first 5 min of treatment and returned to initial values after 30 min of treatment. The sorption capacity continued to increase even when the specific surface area decreased after reaching its peak value. This indicates the important role of surface functional groups formed on carbon fibers during plasma treatment. This is consistent with the results of x-ray photoelectron spectroscopy analysis showing changes in surface oxidation during plasma treatment.