bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear control of active power filter based on LQR control
Authors: Liu Yang , Yang Jian Feng , Qi Ren De , Meng Ning Ning 
Published: January 2021

Abstract
In order to improve the ability of real-time tracking and compensating harmonic of three-phase active power filter (APF), a nonlinear sliding mode control strategy of APF is proposed based on the state feedback linearization theory. In order to improve the dynamic performance and tracking ability of APF system, the affine nonlinear model of APF system is established, and the nonlinear control strategy of current inner loop is designed. The control parameters are adjusted by LQR method. In order to adjust and stabilize the DC voltage of the system, the slip mode control (SMC) is used to design the voltage outer loop. The simulation and experimental platform are built. The experimental results show that the method has good dynamic response, steady-state characteristics and robustness.
Utilizing GPGPUs for simulating quantum circuit
Authors: Xu Yuanfei , Zhang Lixing 
Published: January 2021

AbstractState vector describing the state of an n-qubit quantum system requires 2ncomplex numbers, which means the memory usage of simulating a quantum computer grows exponentially with respect to the number of qubits. For the memory of a single hardware is limited, distributed computation is necessary for simulating quantum systems with large number of qubits. In our proposal, we developed a multi-GPU solution. State vector is divided into several chunks and allocated to different GPU device. Making it possible to simulate quantum circuits of any size on appropriate GPU cluster. We analyse the theoretical computation resource and come to the conclusion that memory copy bandwidth between GPUs is the bottleneck of time consumption. Total execution time is O(logDN/DN) if peer-to-peer memory copy is supported, otherwise time elapsed is O(logDN) where DN is number of GPU devices. Memory consumption on one GPU is O(1/DN).
Research on economical sawing equipment for auto roll-forming frame part adapted to fast switching of multiple varieties
Authors: Peng Li-Ming , Qian Hua-Min 
Published: January 2021

Abstract
Precise angle sawing is an important process to ensure the auto roll-forming frame parts be assembled and welded accurately. Large enterprises can adopt special sawing machine and fixture to meet the requirements. However, this method is not suitable for small enterprises due to its large investment and insufficient flexibility of the manufacturing system. Considering the multi-varieties and small batches production characteristics, economical sawing equipment based on the general cutting machine platform equipped with quick change fixture is introduced. By changing the fixture position on the platform, and replacing a few necessary elements, this equipment can accomplish different angle precise sawing for various auto roll-forming frame parts. Finally the economical technology renovation purpose is realized.
Mechanized operation mode of the key link of Chinese stem and leaf vegetable production
Authors: Guo Qian 
Published: January 2021

Abstract
In China, the comprehensive mechanization level of stem and leaf vegetable production is only about 20%, and the labor cost accounts for about 65% of the total production cost, with high labor intensity and high cost. The mechanization production level of stem and leaf vegetables in China is low, and there are some problems, such as single function of machinery and tools, poor adaptability, low production efficiency, poor operation quality, various links of machinery and tools are not matching, and the planting and agronomy of leaf vegetables are not matching. In this paper, the key technologies and future development trend of the mechanization of stem and leaf vegetable production are put forward, and the direction of the research and development of stem and leaf vegetable production technology and equipment is pointed out.
A Task-Driven Applicable Theory of Autonomous Load Control
Authors: Liu Xinan , Ma Xiao , Yang Shuo , Zhou Na , Yang Xiaoyu , Liu Rui 
Published: January 2021

Abstract
Following manual manipulation to manual remote control, special vehicles are now developing towards task-oriented autonomous load control. Based on the original remote load control system, an autonomous control system architecture composed of “decision-making layer-planning layer-control layer-executive layer” was proposed in this paper, and the “task chain-action chain-instruction chain” autonomous task load control method was devised. This theory transforms the remote fire control system that receives operating instruction and controls units, into a task-driven load system that receives tasks to realize automatic/autonomous control. This provides theoretical support for the autonomous combat of unmanned equipment in the future.
Design of indoor unmanned airship propelled by ionic wind
Authors: He Zhongzheng , Li Pengfei , Wang Wei , Shao Liwei , Chen Xi 
Published: January 2021

Abstract
The indoor unmanned airship is a lighter-than-air aircraft that can hover in the air for a long time without consuming energy. Indoor unmanned airships are widely used in indoor inspections, special operations, commercial advertising, education and scientific research. In this paper, an indoor unmanned airship propelled by ionic wind is designed. The airship can complete motions such as forward and yaw, and almost no noise and vibration are generated during the working process.
Assist the elderly bathing machine
Authors: Chang WenQi , Liu HaoYan , Lu JingJia , Chen Yun 
Published: January 2021

Abstract
Data show that the degree of aging in my country is increasing year by year. Moreover, the elderly’s bathing problem still plagues families. Based on the above situation, the project team designed an auxiliary bathing machine for the elderly. The bathing machine can wash the head, back, limbs and other parts of the elderly that are not convenient for washing, and at the same time assist the elderly to lie down and get up, and monitor the vital signs of the elderly during the bath. The control mode of the bath machine is independent control of each module, and the elderly can activate each functional module by voice or manually. The coordination and cooperation between the various modules effectively deal with the problem of bathing for the elderly living alone, which has high practical value and promotion value.
Mechanical smart cleaning table
Authors: Duan Jinhong , Gan He , Yu Quanzhang , Chen Yun 
Published: January 2021

Abstract
Smart home is the inevitable development trend of future home furnishings. As an integral part of the home system, the dining table is bound to face a qualitative leap. As people yearn for a better, more comfortable and convenient life, the development of the dining table will become more intelligent and humanized. At present, people have a great demand for a variable dining area, and hope to avoid the tedious cleaning of the table after eating, and desire to be free from housework. Based on the above background, the team members designed a new type of self-cleaning dining table-mechanical intelligent cleaning dining table. The dining table has the characteristics of ingenious structure, diverse functions and stable performance, including three functional modules: folding and extending, table cleaning, and garbage collection. The ingenious cooperation between the various institutions can realize the folding and extension of the dining table, table cleaning and garbage collection functions. The mechanical intelligent cleaning table saves people’s time, facilitates people’s lives, and has high practical value and promotion value.
Cigarette end detection based on EfficientDet
Authors: Liao Jianhao , Zou Jiayu , Shen Ao , Liu Jinfu , Du Xiaofei 
Published: January 2021

Abstract
In the process of building a harmonious society in China, smoking in public places is difficult to curb. However, with the continuous development of computer vision, object detection algorithm plays a key role in the above video detection scene. However, if the detection process is not real-time, it can not be applied to smoking scenes in public places, giving people timely judgment. After analyzing a variety of target detection algorithms, this paper considers that EfficientDet can achieve high efficiency under a wide range of resource constraints, and can easily carry out multi-scale feature fusion, so that it has high speed and accuracy in the process of target detection. In this paper, Efficientnet is used as the backbone feature extraction network, and a set of fixed scaling coEfficients are used to scale the depth, width and resolution of the network for preliminary feature extraction, so as to obtain three effective feature layers. Then, in order to improve the prediction level and enhance the feature extraction, the three effective feature layers are transferred to bifpn with cross-scale connection optimization The prediction results can be used as the evaluation results of the model. The evaluation results show that EfficientDet has high mAP.
Design of Laser Cleaning System for Large-scale Plane Workpiece
Authors: Ma Qingzeng , Ren Yuan , Jin Shuo , Nan Leiguang , Ge Hailong , Cheng Wei 
Published: January 2021

Abstract
Surface cleaning is an essential procedure to improve quality and performance of workpiece in modern industrial manufacturing. Among surface cleaning technologies, laser cleaning has been regarded as the most promising green cleaning technology. Laser cleaning is a green cleaning technology that will not cause any environmental pollution. Laser cleaning has the ability of cleaning the area of the designated shape. A set of laser cleaning system that consists of two-dimensional galvanometer and 3-axis motion platform, was designed in this paper. The two-dimensional galvanometer was used to clean the area of the specified shape. The 3-axis motion platform expands the limited cleaning area of the two-dimensional galvanometer to a larger area. Laser displacement sensor is utilized to ameliorate the cleaning quality. To improve the cleaning accuracy of the system proposed in this article, a camera was adopted to recognize the origin of the workpiece and correct the pose of the workpiece. Experimental results demonstrate the performance of the proposed system for large-scale plane workpiece.
Influence of Circumferential Uneven Inlet Conditions on the Aerodynamic Performance of Turbine Stator
Authors: Ji Bing , Wang Zhiduo , Li Jun 
Published: January 2021

Abstract
The application of the combination of rotating detonation combustor and turbine to propulsion system is a recent research focus. This paper verifies the feasibility of this combined propulsion method through numerical simulation, and the flow law and flow loss mechanism in the turbine stator passage under complex inlet conditions are obtained. The results show that the flow field in the turbine stator has serious circumferential unevenness. The interaction between the rotating pulsating wave and the blade is the main cause of flow loss.
Design of a new type of deep hole boring device
Authors: Cai Hao , Dong Zhen , Zhang Zhi Bing , Cui Shuai 
Published: January 2021

Abstract
When boring deep holes, as the workpiece hole becomes deeper and deeper, the size of the boring bar is large, the overhang is large, the vibration of the boring bar is large, and it is easy to deform, which makes the ordinary deep hole boring tool unable to meet the actual complex working conditions. In order to reduce the vibration and deformation of the boring bar and further improve the machining accuracy of the workpiece, a deep hole boring device with auxiliary support is designed. The adjustable support provided by the device can play a role of fixing and guiding during processing, thereby effectively reducing processing vibration and deformation and improving processing accuracy. And completed the trial production and processing experiment of the device prototype. The results show that the machining accuracy of the new cylindrical deep hole boring device is very high and meets the design requirements.
Review of the Research on Augmented Reality Maintenance Assistant System of Mechanical System
Authors: Jia Wenze , Zhu Junyao , Xie Lizhong , Yu Cungui 
Published: January 2021

Abstract
In order to ensure the normal operation of mechanical system and solve the problems of complex structure and insufficient cognition caused by mechanical system updating, the advantages of applying augmented reality technology in the field of fault diagnosis and maintenance are analyzed. Firstly, this paper summarizes the application of augmented reality technology for maintenance assistance cases at home and abroad, analyzes its industry characteristics and application advantages, then summarizes the key technologies of augmented reality, and finally prospects the development trend of the system application.
Structure Design and Simulation of Portable Intelligent Gauge Calibrator Based On ANSYS
Authors: Liu Liang , Zou Wen Zhe , Liu Chuang , Shao Junyi , Liu Yunjia 
Published: January 2021

Abstract
Gauge industry is an indispensable part of China’s railway inspection industry. There are some problems in the traditional gauge industry, such as large volume and low intelligence. In view of the above key points, this paper designs a new portable intelligent gauge calibrator, which greatly reduces the volume of the device. Through the upper computer operating the internal control unit of the device, the automatic measurement of the instrument is carried out. The structure of the new gauge calibrator is analyzed and demonstrated by ANSYS simulation software.
Analysis of docking tolerance capability of underwater tool-switching device
Authors: Gong Haixia , Tang Wei , Tan Bowen , Wang Liquan 
Published: January 2021

Abstract
As part of the Underwater Mechanical hand and Tool Box System, the underwater tool-switching device can carry variety kinds of tools that have general interfaces during one-time underwater operation, like polisher, driller, cutting saw, torque wrench. By operating the underwater ROV Mechanical hand using the remote control system on the land, the workers are able to switch all kinds of tools quickly so that they can enhance the work ability and improve the efficiency of the Underwater Mechanical hand. In this paper, the geometric conditions required for the docking of the mobile end and the fixed end of the docking device are analyzed. Through the projection method, the three-dimensional docking process is transformed into the two-dimensional position equation on the main docking plane, and the mathematical model is established to obtain the docking tolerance range. Then, the simulation experiment is carried out by Adams to verify the correctness of the tolerance theoretical calculation.
Experimental Study on the Performance of Ship Pipeline Coated Vibration Isolator
Authors: Lao Xingsheng , Liu Yong , Dai Chunhui 
Published: January 2021

Abstract
In order to improve the efficiency of ship pipeline vibration isolation, an optimized design scheme of coated rubber vibration isolator was proposed. The natural frequency was calculated and a test bench was established for vibration isolation performance test. The results show that the dynamic and static stiffness of the optimized vibration isolator is significantly lower than the traditional design value at the natural frequency. The natural frequency of the vibration isolator is reduced from about 35Hz to about 9.7Hz from the initial design scheme, and the vibration isolation efficiency is increased from about 20dB to about 33dB as well.
Conversion from Free-Form Surface to Ruled Surface of Centrifugal Compressor Impellers
Authors: Guo Feng , Chen Hua , Li Xiangjun 
Published: January 2021

Abstract
At present, there are several conversion methods exist, which are based on cutter fixing at a point on the blade surface to swing around the blade surface, searching for a position where the error between the cutter and the free-form surface is the smallest. They rarely take into account the benefit from searching cutter position along the blade’s tangential direction, and ignore the possible optimal cutter position from such search. In this paper, we propose a new cutter search method that allows this tangential swing in additional to meridional plane swing of the cutter in searching for the optimal position of the cutter. The mathematics of the method is described, and two different centrifugal compressor impellers with free-form blade surfaces are employed as test cases. The results show that this method can well convert the free-form surfaces of the impeller blades into ruled surfaces.
Research on Damping Mechanism with Resetting Capability for Axial Vibration Control of Satellite Antenna
Authors: Wang Min , Liu Jiaxing , Liu Qinda , Zhao Tingting , Zhang Yunfei 
Published: January 2021

Abstract
With the development of space technology, the large scale space deployable antennas gradually become one of the key research themes of research. The basic requirements for large scale satellite antennas are the characteristics of light in weight and high in profile accuracy. The low-frequency and large-amplitude vibration of the large scale antennas is easily excited when working in an environment with zero gravity. In order to suppress the vibration of large scale deployable satellite antenna, a new type of damping mechanism with resetting capability is presented to improve the ability of vibration energy consumption and ensure the dynamic characteristics of the radial rib structure containing the presented profile accuracy of the antenna. The rod making up the deployment mechanism of the antennas is divided into two parts which connected by using the shape memory alloy (SMA) wires through guiding mechanism. Meanwhile, a metal rubber is fixed and pressed between two parts of the rod by SMA wires. The ability of the friction energy dissipation of the metal rubber is utilized to suppress the axial vibration of the rods. The super elasticity of the SMA wires is used to provide the restoring force for ensuring the dimensional stability of the rod. In this paper, the design principle of the axial self-resetting damping structure is introduced in detail. And, the dynamic characteristics of the radial rib structure containing the presented damping mechanism are investigated by using the software ANSYS. The simulation results show that the vibration amplitude of the radial rib of antennas has been reduced significantly.
A damage-coupled viscoplastic model for compressed asphalt concrete
Authors: Zeng Guowei , Liu Lei , Bai Fan 
Published: January 2021

Abstract
The damage theory is employed to investigate the mechanical strength deterioration caused by micro defects. Introducing the effective stress, this paper presents a damage-coupled viscoplastic model by applying the Schwartz model with an elastic component. The model is calibrated and validated by asphalt concrete creep test under various stresses. With the help of recursive numerical method, the model parameters include viscoplastic and damage functions for different stresses are determined. The result shows the model not only characterize the three stage creep deformation behaviour at a range of stress, but also can predict the damage evolution during the increased creep strain.
Matching and Analysis of Ethanol Engine and Transmission System of Light Passenger Car
Authors: Sun Shuguang , Wang Meng , Zhang Desheng 
Published: January 2021

Abstract
In the process of the matching of ethanol engine and transmission system with a new light passenger car, it is found that the traditional theory formula is complex, and with long time of debugging process and low accuracy. By using Cruise software, the performance simulation model of passenger car is built, simulation tasks are established. Different matching scheme is set up and the simulation calculation of power performance and fuel economy are carried on. The comprehensive evaluation system of index weight is established by analyzing the simulation results. According to the index weight and the simulation result, a better set of combining scheme for vehicle with comprehensive performance indicators can be obtained.
The vibration reduction optimization of the body tube fastening of EM rail launcher
Authors: Lian Zhongmou , Feng Gang , Li Tengda , Liu Shaowei 
Published: January 2021

Abstract
In order to further optimize the vibration reduction effect of the body tube fastening of the electromagnetic rail launcher, the vibration reduction optimization scheme of the body tube fastening is determined by the modal superposition method. The electromagnetic rail launcher is simplified to Bernoulli-Euler beam, the vibration equation of the rail is established, and the inherent characteristics of the rail are analyzed. The multi-field coupled finite element model of the electromagnetic rail launcher is established and the complete transient launching process of the launcher is simulated. Based on the modal analysis of the system stiffness at the critical velocity, the optimal position of the tube fastening is determined, and the influence of different fastening positions on the damping effect is analyzed. The results show that the fastening of the body tube can effectively improve the structural stiffness of the electromagnetic rail launcher, and the damping effect of the fastening is affected by the vibration characteristics of the fastening position. The addition of fastening leads to the stress concentration in the adjacent part of the rail, which increases the requirement of rail strength. When the fastening is set in the front part of the rail, the vibration reduction effect is obvious. When it is set in the back part, the resonance range of the critical velocity should be avoided and the priority should be given to the position before the critical velocity.
Study on the optimization of on-line drilling parameters of slim cigarette to the stability of total ventilation rate
Authors: Qiao Xiaohui , Zhao Jian , Hu Qun , Zhang Tao , Yang Lei , Wu Jiacan , He Xufeng , Xu Yanqun , Pu Qian , Zhao Meiwei , Qiu Ye , Feng Hongtao 
Published: January 2021

Abstract
In order to explore the influence of the number of holes and laser pulse durations on the mean and standard deviation of the total ventilation rate of the slim cigarettes, the optimal range of on-line drilling parameters for different products under the allowable range of the total ventilation rate was determined. In this study, three cigarette products were used, 40 holes (before improvement), and 30 holes (after improvement) were drilled by on-line laser, and the laser pulse durations were adjusted to make the mean of total ventilation rate reach the standard value for comparative analysis. The results show that when the optimal number of holes is 30, the standard deviation of the total ventilation rate of each brand decreases by 24.79%, which increases the stability of the total ventilation rate.
Simulation analysis of gear contact stress in reduction gearbox
Authors: Yang Feng , Fu ZhongYuan , Tian ZhaoDan 
Published: January 2021

Abstract
In this paper, the contact stress of reducer gears is simulated and analyzed, and the assembly error is considered. Application of three-dimensional modeling software SolidWorks helical gear model is set up, and carried out in accordance with the working condition of two kinds of error assembly, including the backlash error and axis parallelism error, and the finite element analysis software ANSYS, the contact surface and tooth root, the contact stress of the online statics and dynamics analysis, it is concluded that the stress under two kinds of error and change situation, the size of the summary analysis of the influence on gear transmission, in the future has reference and guiding significance to the actual production of gear assembly. Combining the powerful modeling function of CAD software with CAE, it embodies the integration of CAD and CAE technology.