bluuebunny/crossref_metadata_2025 huggingface dataset:
The Traveling Wave Protection of HVDC Based on HHT Conversion
Authors: Hou Yunhai , Zhang Shuhan , Sun Haoxin
Published: November 2020

It is significant to the whole system or its connected network and to run safely and steadily by detecting and cutting out faults fast and accurately. In this paper, a new transient signal analysis method is got based on the Hilbert-Huang Transform conversion. It’s original is that by making simulation on interior and external district of direct current through HVDC transmission model, and using MATLAB to analyze transient voltage signal on every fault, and then a protection project of high voltage direct transmission line is proposed based on HHT. The simulation results show that the scheme overcomes the inherent defects of the traditional algorithm, and makes up for the shortage that the protection is easily affected by the transition resistance and can not be accurately judged when the ground fault occurs, which effectively improves the detection accuracy and speed of the line protection.
A Signal Reconstruction Method Based on Quadratic Spline Interpolation Applied in Power Quality Analysis for SCM-TTU
Authors: Deng Siyang , Liu Zhu , Huang Lvchao
Published: November 2020

Aiming at the accurate and quick analysis of power quality especially of harmonic problem in power system, interpolation approaches should be applied if the samples collected by hardware are not matched with Fast Fourier Transform (FFT) calculation. A quadratic spline interpolation algorithm is proposed on Single Chip Micyoco-Transformer Terminal Unit (SCM-TTU) in this paper. This algorithm considers the continuous of interpolation function and also the first derivative in order to improve the accuracy. It could be applied before FFT calculation to avoid the mismatch of sampling rates. A simulation with mathematic example and also an application with SCM-TTU contains the harmonics from 2nd to 50th orders are experimented, results are presented to show the effectiveness.
Way to Protect Electrical Wires Against the Break under the Strong Wind
Authors: Kobelev Evgeniy , Voinov Kirill , Esbulatova Altyn , Andreev Jury
Published: November 2020

In many countries in the world the strong wind can break wires very easily. In this case many regions and very important objects will be without of the electrical energy and lighting. To find quickly the place where this situation had happened it takes many hours. It is a great problem. Everybody knows that it is rather difficult to reach this damaged place (maybe in the forest or among the high hills). Strictly any repair takes usually many hours too. That’s why it is needed to find the simplest method to defend any long wires against their break under the strong wind. In this situation if the strong rushes of the wind begin to swing wires intensively, they cannot sustain such overloads too long. Moreover, the resonance phenomenon in these oscillations will be without fail and breaks wires very quickly. In this article there is a new way how to protect any wires against the break using only several hard rods fixed firmly on the wires. How it can be done it is described in detail below and some of recommendations including the results of experiments are shown also.
Knowledge Extraction Method for Power Grid Fault Text Based on Ontology
Authors: Peng Bo , Lai Ji , Hao Yanru , Yuwen Mengke , Xiao Ding
Published: November 2020

The power industry usually records equipment failures, defects and other information in the form of text, which contains lots of regular patterns. Knowledge extraction in fault text is of great significance to improve efficiency and reduce the labor cost in the power industry. However, the research for knowledge extraction of text information in this field is rare, it is even more difficult to use machine learning algorithms to mine the deep patterns. To solve this problem, a method of knowledge extraction is proposed in this field. We use power equipment fault texts and relevant guidance as raw materials. Firstly, the knowledge base of this field is designed and constructed based on the ontology concepts, including ontology concept base, description base and regular expression base. Then, the knowledge extraction algorithm is designed according to the knowledge base. After that we conduct the knowledge merge operation to make the extraction results more accurate. Experiments on the real fault texts shows the feasibility and the high accuracy of our method when compared with artificial extraction.
Real Time Energy Efficiency Operational Indicator (EEOI): Simulation Research from the Perspective of Life Cycle Assessment
Authors: Sun Chao , Wang Haiyan , Liu Chao , Zhao Ye
Published: November 2020

In order to evaluate the effect of CO2 emissions during ship building, maintenance and scrapping on energy efficiency, a real time EEOI definition was put forward, a life cycle assessment calculation framework was established, and a ship propulsion model with main diesel engine was built. A bulker carrier YUMING was taken as the case ship. CO2 emissions during ship building, maintenance, and scrapping were calculated. Main engine revolution and real time EEOI value with other parameters were obtained by simulating in different ship draft. The results show that life cycle assessment result will explicitly increase the real time EEOI value especially in lower engine speed and lower ship draft. It means that slow steaming may bring less environmental benefit if the life cycle assessment result is involved.
Research on the Integrated Electronic Signature Service Platform of Energy and Power
Authors: Li Lili , Liao Huimin , Xuan Jiaxing , Wang Huinan
Published: November 2020

In view of the many problems faced by the electronic signature service in the power industry, such as the increase of the media and types of storing digital certificates, the diversity of service modes of electronic signature, and the comprehensive support of the national secret algorithm, this paper proposes a scheme of the integrated electronic signature service platform. The platform adopts SDK interface to call its signature and verify signature, middleware and certificate service provide the interaction between application and digital certificate, realize the coexistence of multiple signature modes, meet the diversified electronic signature services of power users, improve the security of signature, and better serve the development of power business.
Analyzing the Limit Loading of Transmission Tower by Means of Finite Element Model
Authors: Jiang Ruixuan
Published: November 2020

The truss structure has been widely used in the area of high-voltage electric power transmission due to its limited mass and great stiffness. The carrying capacity should be known in advance before the practical usage of transmission tower. As a result, analyzing the limit loading of transmission tower can be significantly useful. In this research, a model of transmission tower structure has been established by a software named Abaqus 6.14. By imposing different loading forces to the finite element model, the locations of limit stress and displacement were figured out. It has shown that the truss structure in this article can bear no more than 198 kN of loading. Stresses meanly distribute in the two side of the tower body, decreasing with the increasing height. The limit stress shows up at the bottom and is at same side of loading force. Stress and displacement responses fit Hooke’s law perfectly, in other words, the proposed finite element model can be used in the design of transmission tower in practice.
Research on 3D Location Method of Underground Cable
Authors: Li Zhe , Nie Yixiong , Lin Xiuyue
Published: November 2020

Power cable is one of the most widely used electrical equipment in distribution system. Due to some historical reasons, the accidents such as cut or damage cables during construction often occur. In this paper, the calculation model of power cable power frequency magnetic field under different laying conditions is established. Based on the analysis of magnetic flux density around power cable, a positioning method of underground cable based on electromagnetic method is proposed. Three horizontal magnetic field sensors are used to locate the path of the cable,two vertical magnetic field sensors are used to locate the depth of the cable, so as to realize the three-dimensional positioning of the power cable. The simulation results of MATLAB show that the average absolute error of the method is about 0.03 m when the sensor array is 0.35 m around the cable in path positioning, and it can accurately locate the location of underground cable in depth location.
Research of Non-contact Compensation AC Voltage Regulator Based on Fuzzy Strategy
Authors: Li Weibo , Li Qi , Gao Jiajun , Zhao Xueting , Pan Junfeng
Published: November 2020

The non-contact compensation type AC voltage regulator possesses the advantages of small size, high efficiency, low cost, etc. due to its simple structure and convenient control, and is widely used in the field of AC voltage regulation technology field. However, the non-contact compensation type AC voltage regulator belongs to the class of voltage regulation. And the characteristics of the discontinuous system has the disadvantages of low control precision and weak system reliability. Fuzzy control strategy, through fuzzification and approximate reasoning, can solve the problem of such discontinuous control systems. Some research work shows that using the fuzzy membership strategy to optimize the switching rules of the control system can greatly improve the control precision of the voltage regulation, that is, can improve the regulation accuracy of the AC voltage regulator. The experiment results verify that the regulation accuracy of the system after optimizing the switching rule is 5-10 times pre-set, which proves the effectiveness of the improvement.
Research on Fault Monitoring Technology of Distribution Network Based on Fuzzy Association Rules Mining
Authors: Zhang Wei , Liu Yumin , Liu Zhu , Wang Shilin , Zhen Zijing , Li Yixin
Published: November 2020

In order to monitor the operation status of distribution network in real time and ensure the security and stability of distribution internet of things, a fault monitoring method based on fuzzy association rule mining was proposed. Fuzzy association rules mining was used to build the normal state parameter model of distribution network. The degree of interest index replaced the traditional index, aiming to improve the association degree between the rule parameters and form an effective expert knowledge base. According to the rules in the expert knowledge base, the normal state data of distribution network were obtained by fuzzy reasoning. Further, the state similarity function between the monitoring states and the normal states was used as the state judgement index. When the similarity is lower than the threshold, the fault alert should be triggered. Taking the single-phase ground fault data of distribution network simulated by MATLAB Simulink as an example, it was verified that the proposed method can effectively monitor the single-phase ground fault.
Torque Control of DC Torque Motor Based on Expert PID
Authors: Xu Xinyu , Li Dazhai
Published: November 2020

Torque motor is a kind of special motor with a large number of poles, which can continue to operate at low speed or even when the rotor cannot rotate (that is, the rotor cannot rotate) without causing damage to the motor. In most cases, in order to meet the needs of industrial production and life, we need to torque motor for high-precision torque control. In this paper, we applied the expert PID control method to torque control. MATLAB simulation and experimental results show that the expert PID control has achieved good results in torque control of torque motor.
Wireless Control System Design for Coal Transportation Plant Based on Two-part Tariff System
Authors: Xue Qing , Du Xinhui , Qiao Zuojiang , Wang Ze
Published: November 2020

Under the current tariff policy, large industrial users, such as coal transportation companies, are typically charged a two-part tariff. This tariff policy limits the maximum value of the average load every fifteen minutes for a month, with an additional charge for electricity consumption when the threshold is exceeded. The article proposes a wireless monitoring and control system for coal transportation plants in response to this policy. First of all, the backup power supply and control circuit were added to the electric equipment of the coal transportation plant. Then build a ZigBee wireless sensor network, terminal and relay connected, coordinator and PLC connected. Finally, when the sensor monitors the actual electricity consumption is about to reach the maximum value set in the PLC, PLC sends a command through the ZigBee to control the relay action and switch to the backup power supply. The experimental results show that the wireless control system has a clear structure and effective strategy, which can reduce the basic electricity cost of the coal transportation plant.
Research and Implementation of Constant Pressure Control with Electro-pneumatic Proportional Valve
Authors: Zhao Tangchun , Huang Dunhua
Published: November 2020

In this paper, the implementation method of “constant pressure control” in industrial production is proposed. Through experiments, the feasibility of using pneumatic proportional and open-loop control technology is proved. The control system has the characteristics of high precision, convenient debugging and good economy, and has high practicability.
A Backstepping Control of Plant Protection Boom System Considering Input Constraints
Authors: Li Shujiang , Wu Yue
Published: November 2020

Aiming at the plant protection machine boom system with input constraints, uncertain disturbances and various nonlinear factors, a backstepping controller considering input saturation uncertain interference is proposed. The method introduces an auxiliary system, realizes the compensation of control saturation by designing new error variables, and solves the amplitude constraint problem of the control input. By constructing the appropriate Lyapunov function, the stability of the planter boom system is guaranteed. The simulation results show that the designed controller has good tracking performance and robustness.
Application of Remote Control Technology in Gas Drainage Drilling Rig in Coal Mine
Authors: Wang Qingfeng , Xin Dezhong , Chen Hang
Published: November 2020

In view of the potential safety hazards such as gas-shot, gas-outburst and personal injury in the construction of gas drainage and drilling in coal mine, the technology and equipment of controlling drilling rig far away from the drilling field are studied to improve the automation level[1]. This technology can realize the “one-key” mode to control the drilling machine to automatically up and down the drill pipe, automatically drill and back out, reduce the number of field operators, and play a positive role in ensuring the safety of gas extraction drilling personnel and reducing personnel and increasing efficiency.
Modeling and Simulation of K2x8 Five Axis Machine Tool Based on VERICUT 8.0
Authors: Ye Xuanlin , Yin Jingjie , Cai Jin , Xu Lianjiang
Published: November 2020

Taking the VERICUT 8.0 software as the platform and k2x8 five axis machine as an example, this paper expounds the method and steps of constructing non orthogonal five axis machine simulation machine. The key technologies such as the modeling of machine tool, the construction of machine tool kinematic chain, collision detection and stroke setting, the configuration of control system and simulation are introduced in detail. And the impeller is used as a sample for numerical control simulation processing, which verifies the correctness and effectiveness of the simulation platform, and provides a useful reference for other five axis machine simulation platform configuration.
Automatic Detection of the Underwater Stationary Artificial Torpedo-shaped Target Based on SAS Image
Authors: Li Ke , Wang Xichen , Dai Yating , Zhou Jincong , tong Yishuo , Jiang Wei
Published: November 2020

Aiming at the problems of speckle noise, seafloor background scattering interference and lack of texture feature in SAS images, an underwater torpedo-shaped artificial target detection algorithm based on Meanshift filtering and Ostu algorithm was proposed. Firstly, based on the image characteristics, the Meanshift filtering algorithm is used to confirm a appropriate threshold to achieve a smoothing effect, and eliminate the strong background speckle noise. Secondly, Ostu algorithm is used to perform binarization according to the histogram statistical information after image gray-scale. Finally, the Region growth method is used to find and eliminate the large and unrelated white areas, meanwhile, fill the holes in the target to obtain a relatively complete target contour. The experimental results show that the algorithm is simple, has a strong ability to overcome the background noise. The automatic detection of the target is accurate. The algorithm is stable with a strong engineering value.
Study on a Fast and Accurate Control Loading Device
Authors: Di Jianhui , Xie Xianming , Zhou Yu , Zhou Jiangang
Published: November 2020

A fast accurate control loading device is studied, which is mainly used by the metrological department for calibration and verification of motor vehicle weighing instrument and overload system. By way of control algorithm and the servo motor that drives lifting mechanism, the device is employed to perform a fast and accurate calibration and verification of weighing equipments, such as motor vehicle axle (wheel) weighing instrument and curb weight tester, resulting in higher working efficiency and lesser labor intensity.
A Power De-coupling Control Strategy for MMC-HVDC System
Authors: Zhang Mingguang , Chang Jianhua , Yang Chengming , Liu Zilin
Published: November 2020

Modular multilevel converter (MMC) has a wide range of applications in the field of HVDC. However, some of the electricity in MMC is coupled, which makes the design of control system more difficult and have a negative impact on the stable operation of the system. This paper puts forward a strategy to eliminate the coupling control, this method compensates the current cross-coupling terms of the d-axis and the q-axis in the dq coordinate system, SOGI(Second Order Generalized Integrator) and Q-PR(Quasi-PR) controller are used to accurately control the double frequency circulation in the internal unbalanced current, the coupling caused by the internal unbalance current and the sub-capacitor module voltage is compensated in the three-phase coordinate system. Finally, the simulation verification is carried out in PSCAD, which is compared with the traditional control method to verify that the proposed method can achieve complete power decoupling.
Virtual Reality Combat Trainer
Authors: Zhuang Changkuan , Zhuang Yuxin , Yang Liu Sindy
Published: November 2020

This research reveals a system that can support combat training and games, in order to enable the combat enthusiasts who have not been trained professionally to carry out actual combat training and experience. On the basis of ensuring the safety, this study describes the virtual combat trainer from the perspective of enhancing the actual combat experience. It also describes the meaning, function, technical principle, technical characteristics and innovation of the product. This research is mainly used in martial arts fighting training, competition and other aspects.
Integrated Disturbance Observer Attitude Controller for a Satellite with Rotating Solar Array
Authors: Wang Haoguang , Wu Guoqiang , Bai Tao
Published: November 2020

In this paper, the response of on-orbit satellite attitude under the influence of flexible satellite’s solar array rotation is analysed, and a robust attitude control method based on disturbance observer is proposed. The disturbance torque is estimated and compensated feedforward. The simulation results show that the proposed control method can effectively estimate the external disturbance, and significantly improve the attitude control accuracy and stability.
Design Method of Local Control System Centred on IOT Technology
Authors: Liu Jianbao , Zhou Feng , Qin Xinxin
Published: November 2020

For realizing the comprehensive monitoring of the ships and warships, the internet of things (i.e., IOT) technology is adopted by the local control system, which consists of the sensing layer, the transmission layer and the whole ship monitoring layer. First, state data is collected by various high-precision sensors of the sensing layer, and then transmitted to the entire ship monitoring layer via the entire ship transport layer based on Modbus TCP/IP design. The local control system is based on the STM32 MCU. It integrates functions such as signal acquisition, Ethernet, CAN bus communication, interactive display, and fault diagnosis. The effectiveness, practicability and flexibility of the on-site control system were verified by a ship propulsion experimental system. The on-site results can provide and verify big data technical support for different regions, regulatory agencies and equipment maintenance of the whole ship.
Fixed-time Adaptive Control for A New Three-dimensional Nonlinear System with Circular Equilibrium
Authors: Wang Yaoyu , Liu Ling , Cai Xinshan , Liu Chongxin , Wang Yan
Published: November 2020

In this paper, we proposed a new nonlinear chaotic oscillator. The model of the system is given through a predefined form. Its unique property lies in the circle-shaped equilibrium. Both analysis and simulations are presented. In particular, the stability of the neighbourhood of the equilibrium point is analysed in terms of theoretical derivation and dynamic behaviour. Moreover than that, a robust control method of a category of three-dimensional chaotic systems is designed. And the final simulation results proved the effectiveness of the controllers.
A Classification Algorithm of Fish Feeding Behavior for Automatic Bait Feeding Control
Authors: Zhang Jialin , Cen Feng , Xu Lihong
Published: November 2020

In aquaculture, automatic feeding control of fish can effectively improve production efficiency. However, most automatic feeding devices are open-loop control because of lack of information on fish feeding behavior, which could lead to a large amount of bait waste. To address this problem a novel video classification algorithm based on an inter-frame relationship Bayesian estimation network(IRBEN) is proposed in this paper, which provided prior knowledge for automatic feeding control of fish. The IRBEN first employs a VAE encoder to convert the frames of a video clip into multivariate Gaussian distributions(MGDs). Then, two fully connected networks, one is trained on the MGDs associated with the fish eating video clips and the other on the MGDs associated with the fish noneating video clips, are employed to predict the MGDs of the frame after an interval from the MGD of the current frame. The classification is conducted by finding the fully connected network achieving smaller KL distance between the predicted MGD and the actual MGD. The experimental results show that the IRBEN achieves the classification accuracy of 97.5%.
Experimental Study on Braking Performance of an AT Integrated Hydraulic Retarder of HPT Series
Authors: Song Zhenchuan , Li Huiyuan , Xu Ming
Published: November 2020

In this paper, the hydraulic working principle of an AT integrated hydraulic retarder of HPT series is introduced, and the braking performance is tested on a bench. The braking characteristics under different solenoid valve currents and different retarder rotational speeds are obtained and analyzed. According to the test results, the optimization method of braking characteristics in high speed section is studied.
Instantaneous Dynamic Deformation Monitoring on Jiaozhou Bay Cross-sea Bridge with LVR-GPS Technology
Authors: Zhao Yongqian , Yu Chengxin
Published: November 2020

Intend to get and process the monitoring data of the instantaneous dynamic deformation of Jiaozhou bay cross-sea bridge sufficiently, the paper makes application of the long visual range and the global positioning system (LVR-GPS) monitoring model in the experiment. The deformation monitoring experiment is conducted with horizontal distance exceed more than 2.2 kilometers. With the LVR-GPS model we can monitor multiple points, draw real-time curve image, and obtain the synchronous results. Thus, we can provide a creative deformation monitoring technology on the similar large-scale bridges.
Gesture Recognition Method with Illumination Robustness for Wheelchairs
Authors: Zhang Bin , Luo Xianyun , Gao Qiang
Published: November 2020

Disabled elderly people have to rely on wheelchair life. And the wheelchairs are used in daily life with different illumination conditions. This paper proposes a hand gesture recognition method to control wheelchairs based on dynamic colour clustering. As dynamic clustering skin detection algorithm is used, the gesture recognition accuracy is improved. Using skin detection, arm removal and polygon fitting methods, the gesture images collected by a Kinect V2, are recognized as control commands to drive the wheelchair. Experiments show that the proposed method can be applied to different illumination conditions with better recognition accuracy.
Automatic Target Recognition Technology of SAR Images Based on 2DPCA+PNN
Authors: Xu Ruiming , Li Dong
Published: November 2020

In this paper, the SAR image in MSTAR data is used as the research object. The target recognition algorithm based on probabilistic neural network (PNN) is mainly studied. It includes three parts: SAR image preprocessing, feature extraction, classification and recognition. Lee filtering and adaptive threshold method are used to filter the speckle noise effectively, and the 2DPCA principal component analysis method is used to reduce the dimension of the image and obtain the 10 dimensional image features. The recognition part is input to the PNN training test with the acquired feature vectors, and the 85.17% correct recognition rate is obtained, and the target classification and recognition of the SAR image is completed.
Numerical Simulation of Fluid Carrying Pollutant Particles Erosion in Elbow Pipe Is Carried out by COMSOL
Authors: Yang Shuren , Zhang Min , Wang Xingang , Wang Hongxi
Published: November 2020

With the development of Marine energy to the deep and ultra-deep-water field, the severe environment of high temperature and high pressure in the engineering background makes the problem of flow security in oil and gas transportation system more serious and prominent. For this part of the underwater production and processing system, more stringent requirements are put forward. In order to study the erosion of fluid pipelines such as oil and natural gas, the COMSOL (A large-scale advanced numerical simulation software) finite element model was used. Under the condition of different flow parameters, the erosion trajectory of solid particles in the pipeline and the erosion failure rule of the bend are obtained. In this paper, the erosion wear rate of 90° pipe elbow is calculated, and three different erosion models are compared.
Roadside Unit Deployment of Cooperative Vehicle-Infrastructure System Based on Digital Measurable Image Method
Authors: Liu Jianping , Cai Lei , Wang Xinke , Lyu Chenyang , Zhang Li
Published: November 2020

As the trend of the new generation of intelligent transportation systems, the application of the cooperative vehicle-infrastructure system (CVIS) is important to reduce traffic congestion and accidents. For the cooperative vehicle-infrastructure system, the roadside unit (RSU) is a new application without enough deployment experience. Meanwhile the deployment of traditional mechanical and electrical infrastructure is generally based on experience and is easy to change the design. This paper analyzes the key technical parameters of RSU and the Digital Measurable Image (DMI) method in context of the CVIS. After collecting field data from a smart highway pilot project (the Deqing-Fuyang expanded Huzhou section in Chang-Shen Highway) and matching the DMI method with highway mileage pile numbers, an RSU deployment scheme based on DMI data was completed. It provides significant support for smart highway demonstration projects with cooperative vehicle-infrastructure intelligent management and control applications.
Development of Parametric Design Software for Shearer Spiral Drum
Authors: Huang Qiulai , Tang Qi , Jia Tengfei , Liu Changli
Published: November 2020

In order to improve the design efficiency of the shearer drum and achieve rapid optimization, it is proposed to establish a parametric design system for the shearer spiral drum centered on design, optimization system and parametric modeling technology. The overall idea of implementing the system, the function and design analysis of each module are expounded, and the key technologies are discussed. Using Solidworks as the platform, the parametric design of the shearer spiral drum was developed with VB.Net, including the modification of the drum size, the automatic drawing of the cutting diagram, the load calculation of the pick and the automatic generation of the loading blade parts and their unfolding engineering drawings. Finally, it was verified with a 1800x630 roller. Tests prove that the system can quickly optimize the shearer drum, improve the speed and accuracy of drum development, and reduce costs.
Study on Evaluation Method of System Efficiency of Pumping Wells
Authors: Xie Wei , Chen Lei , Wang Fang , Li Yun , Yang Mengshi , Wang Lin , Xia Zhixue , Wei Haiyan , Gao Hongchao , Wang Bin
Published: November 2020

For a long time, there is no unified method and standard for efficiency analysis and evaluation index of pumping well system. Therefore, this paper studies the theoretical extreme value of pumping well system efficiency. Based on the model of system efficiency evaluation method, the single factor analysis and comprehensive impact analysis are carried out, and a set of simple and convenient evaluation method of pumping well system efficiency is found out by using examples. It provides strong technical support for relevant technical departments and different oil production units to reasonably formulate measures and plans.
Research on the Health Intelligent Management System of Large Wind Tunnel
Authors: Zhang Hao , Liu Zongzheng , Liao Wenlin , Chen Xiaoguang , Chen Zhenhua
Published: November 2020

In the national major projects, health management of key infrastructure has been paid more and more attention. Wind tunnel is a national strategic infrastructure. The health management system is of great significance to promote the safe, efficient and reliable operation of large-scale wind tunnel. In order to establish a wind tunnel health intelligent management system, it is necessary to realize the dynamic state monitoring, intelligent fault diagnosis, intelligent fault prediction, independent maintenance support and integrated equipment management. Facing the great demand of designing and constructing the world’s top wind tunnels, this paper makes an exploratory research on the health intelligent management system of large wind tunnel. By means of data mining, machine learning and virtual reality, the health management system can have the ability of self-study and self-improvement. So as to realize the development of the health management of wind tunnel to the depth intelligent.
Experimental Study on Local Heat Transfer during Quenching Process by Slot Nozzles
Authors: Jiang Peng , Wu Licheng
Published: November 2020

Quenching is widely used in industrial applications. The heat is transferred from the ingots by spray or jet cooling at the secondary cooling zone. In this research work, the effort is focused on the influence of jet inclination on heat transfer in the boiling process, as well as the influence of heat transfer rate by changing the jet velocity through experimental work using Nicrofer sample under 850 ˚C. Different angles of the jet (25°, 45°, 65°, 90°) and flow velocities (3.5 m/s, 4.8 m/s, 7.8 m/s, 12.0 m/s) were arranged in these experiments respectively. The results indicated that due to the strong cooling effect of jet quenching the Leidenfrost point was not captured. Both the jet angle and jet velocity played important roles in promoting the cooling process. The smaller the jet angle, the faster the quenching rate. The angle of 25° presented the most optimum cooling effect. The higher the jet velocity, the shorter the cooling time. For the maximum jet velocity in this experiment v=12.0m/s, DNB-temperature even was not identified.
Experimental Performance Research of Vertical Axis Wind Turbine with Expandable Airfoil
Authors: Shen Junjie , Tang Zhipeng , Yan Wuseng , Chen Peng , Zhao Xingyu , Dong Hongkai , Li Wuhao , Zhang Changcun
Published: November 2020

In order to improve the wind energy utilization of the vertical axis wind turbine (VAWT), a new type of VAWT with expandable NACA0012 airfoil is proposed in this paper. The airfoil has opening and folding state. The airfoil is open in windward which is similar with curved blade in Savonius tubine. And it is folded in leeward which is similar with airfoil in H-type turbine. In this paper, a wind tunnel test system is designed to measure the aerodynamic performance of the new turbine and three main structural parameters of the turbine are analyzed. The structural parameters contain the maximum unilateral open angle which influence the flatten of the blade and the sweep wind area. The revolution angle of the rotor corresponding to the self-rotation open angle which influence the effective working time and the airfoil self-rotation effect on the turbine rotation. And the revolution angle of the rotor corresponding to the self-rotation folded angle of the airfoil which influence the wind resistance and impact on the turbine in rapid folding process. The results show that the maximum wind energy utilization of new turbine with appropriate airfoil structural parameters and tip speed ratio corresponding maximum wind energy utilization is higher than Savonius turbine which means the performance of the new turbine capturing wind power is better than Savonius turbine and can be more suitably used in areas with relatively barren wind resource.
Research on Verifying the Accuracy of Finite Element Analysis on the Steel Strips of Boneless Wipers
Authors: Han Bin , Xia Jianrong , Li Jun , Hu Qianjin , Chen Hongyan
Published: November 2020

In order to verify the accuracy of finite element method for detecting the strain distribution trend on steel strips of boneless wipers, a series of measures were taken. The strain values of eight points evenly distributed on the upper surface of a steel strip were measured experimentally. A finite element analysis of the model of a steel strip was performed using ANSYS 18.0 to obtain the strain values of these eight points. Comparing the simulated strain values with the experimental measurements, it is found that the distribution trends of two is consistent, but the simulated strain value of each point is much smaller than the experimental measurement. The reason for this error is that the influence of the self-gravity of a steel strip in the experiment was not eliminated. In future research, the experimental method should be improved to eliminate the influence of the self-gravity of steel strips on the experiment.
Mechanism and Optimization of Pilling Propensity of Wool Fabric Drying in Dryer
Authors: Wei Yuhui , Su Zhaowei , Wang Zongqian , Yuan Huifen , Li Changlong
Published: November 2020

In order to explore the pilling mechanism of fabrics drying in domestic dryers, the pilling propensity and surface morphology of wool fabrics after drying were intensively investigated and compared under different rotating-drying models with help of pilling box and Scanning Electron Microscope (SEM). Results showed the pilling mechanism of wool fabric drying in dryer is not temperature mechanism but rotating-drying models (mechanical movement models of drum) mechanisms. Therefore, the model of alternating clockwise and counterclockwise rotating-drying in dryer should be regarded as appealing rotating-drying model for the wool fabrics drying in dryer.
Research on Coordinate Conversion and Error Analysis of BLSS-PE
Authors: Yu Lewen , Zhan Kai , Zhang Da
Published: November 2020

In this paper, a 3D laser scanner for mining named BLSS-PE is proposed, based on a commercial rangefinder with two servo motors. The coordinate transformation model in different coordinate systems is put forward and the model solving strategy is given. By establishing the error model of BLSS-PE and comparing the measurement data, the results show that the accuracy of BLSS-PE data can be improved after the external factors are included in the system error model, which verifies the feasibility and correctness of the optimization model.
Research on the Simulation Process for the CFETR Divertor Assembly in Delmia
Authors: Dai Huaichu , Lv Gang , Huang Wenjin , Qin Qiang
Published: November 2020

Divertor is an important inner component for Tokamak. In the conceptual design stage, the divertor should be assembled according to the design process in order to guide the work in site. Inner and outer targets, Dome, cassette body are studied in terms of their assemble process to validate the assembly process. Besides, Inner and outer targets and Dome are connected to the cassette body to form the whole divertor model in Delmia. Therefore, it is feasible to do assembly simulation in the virtual environment.
A Design of Lightweight Walking-Assisted Skeletal Robot
Authors: Zhang Lin , Liu Xingchen , Xia Haishan
Published: November 2020

At present, the robot is in a full swing state in various industries, and intelligent equipment can be seen everywhere. With the development of science and technology, the intelligence, reliability and functional extensibility of the exoskeleton robot have to be further improved. Most of the robots sold in the existing market are service robots, domestic robots, and so on, while walking-assisted robots are few. Taking into account the above mentioned, this project is committed to the design and improvement of a lightweight walking-assisted skeletal robot which is composed of STM32 controller, sensor detection, feedback module, action module, mobile APP client and other units. It can identify the step width and pace to the STM32 data, through the gait and stability analysis, real-time adjustment of transmission device to drive the bone mechanical body, help the old man and the security of the disabled to walk. The system could be used for different operating modes of the pressure, acceleration, the heart rate and other non electrical parameter detection and processing.
Simulation Optimization Design of Set Parts Supply System for Automobile Assembly Line
Authors: Chen Xuehong , Zhu Haiping , Guan Hui
Published: November 2020

This article studies material distribution system of mixed-model assembly line. A new material distribution model, set parts supply (SPS) system, is applied to a practical automobile assembly line (S Company) with a takt time of 80s. Firstly, Plant Simulation is used to build the material assembly system simulation model. For the distribution area subsystem, to maximize picking efficiency, material layout and task allocation plan of distribution area are obtained through simulation combined with genetic algorithm with two-chromosome expansion coding mode. As for material transporting subsystem, Design of Experiment (DOE) method based on simulation model is used to achieve the optimization of system parameters such as number of AGVs, capacity of buffer and so on.
Research on Key Strategies of Green Design and Manufacturing Based on Valve
Authors: Xu Yong
Published: November 2020

The paper analyzes the existing problems about low design efficiency and reliability, poor interchangeability and high resource consumption in the design and manufacture of valve industry, designed a set of green planning,green design and manufacturing scheme based on the key technology of green design and manufacturing, such as network and big data platform,provides the maneuverable idea of sustainable development for valve industry.
Research and Application of “Rhythm and Rhyme” in the Modelling Design on Agricultural Machinery Product
Authors: Chen Wei
Published: November 2020

Nature gives rhythm and rhythm to farmland and crops. Then, as agricultural machinery products serving agriculture, its modelling design should also adapt to the nature of nature, fully embodies the “rhythm and rhyme” aesthetic feeling, harmonious in nature. In the modelling design of agricultural machinery products, rhythm and rhyme are often used to obtain the aesthetic feeling of machine modelling. Due to the structure and function of agricultural products, design often emphasizes the rhythm and rhyme of the repeated side
A Study on Fault Diagnosis of Rotating Machinery Combined Wavelet Transform with VMD
Authors: Zhou Huan , Wang Hao
Published: November 2020

Effective diagnosis of rotating machinery is difficult in view of the complex structure, weak early fault signals, non-stationary and non-linear vibration signals, and low signal-to-noise ratio. In this paper, a fault diagnosis method is proposed based on particle swarm optimization (PSO) and variational modal decomposition (VMD). Firstly, wavelet packet threshold is denoised on the signal, VMD is decomposed on the reconstructed signal, and PSO is optimized on the inherent mode function (IMF) obtained from decomposition so as to determine the best IMF function. Then Hilbert transform and envelope spectrum analysis are carried out on the IMF function, and the envelope spectrum analysis result is compared with theoretical calculation frequency to finally determine the fault type. The results indicate that this method can effectively reduce noise components in signals, extract weak fault information and realize fault diagnosis.
The Development Trend of Internal Combustion Engine
Authors: Wang Zhibin , Pan Xiaobing , Zhang Wei , Zhao Yu , Li Haiming , Liu Peng
Published: November 2020

With the development of internal combustion engine technology, internal combustion engine has been widely used in automobile, ship, electric power and other industries due to its advantages of high power density, high heat utilization rate and good economic performance. This paper analysed the advantages, the development process and current situation of internal combustion engine technology, while the development trend of internal combustion engine technology is prospected. Internal combustion engine technology will get greater development in the future.
The Design of Receiver with Low Complexity for PDMA System
Authors: Tang Wanwei , Fu Xueqian , Kang Shaoli , Zhao Jinlong , Ma Zhuang , Wang Lixia , Zhang Xiurong
Published: November 2020

As one of promising non-orthogonal multiple access scheme, pattern division multiple access (PDMA) scheme is considered to be one competitive multiple access technology for the fifth generation (5G) communications. The detection algorithm is the key technology to improve the system performance. Due to the PDMA patterns sparse nature, belief propagation (BP) become one effective receiver algorithm to achieve close to maximum likelihood (ML) detection performance with lower complexity. However, the complexity order is still exponential with the row weight of the PDMA pattern and the modulation index. A novel receiver based on expectation propagation (EP) algorithm is proposed in this paper to reduce the complexity order from exponential to linear. This paper makes a comparison on the two algorithms above in terms of system performance and complexity. Link-level simulation results show that the proposed EP receiver achieves nearly the same performance as the BP receiver with orders less complexity.
Design of A GIS Pipeline Robot for 220KV Substation
Authors: Li Wensheng , Jiang Zhipeng , Zhong Liqiang
Published: November 2020

As an important development direction of substation equipment, a large number of GIS equipment are installed in the power system. Once the GIS equipment has internal faults, it is very inconvenient to find and deal with. This article designs a miniature maintenance robot for GIS equipment, which can be put into the busbar be through the GIS equipment maintenance hand hole cover; the robot has the ability to walk in the GIS equipment busbar tube; the robot carries a small camera device, which can check internal problems and return images; The robot is equipped with a manipulator, with vacuuming and grasping functions, which can complete simple cleaning and bolt tightening operations.
Design of a H∞ Robust Controller for a Small UAV
Authors: Chen Xiaoyan , Dong Chaoyi
Published: November 2020

For Small Unmanned Aerial Vehicles (SUAV), because of its wide flight envelope and its own flight control system has many uncertainties, the aircraft itself is also vulnerable to strong interference such as atmospheric turbulence, so a robust controller is required to meet the specific performance requirements. In this work, a H∞ algorithm, based on a Linear Matrix Inequality (LMI), is used to the design of multivariable flight control system for the longitudinal motion mathematical model of a SUAV in a key laboratory. The simulation result demonstrated that the control system cannot only guarantee the stability of the closed-loop, but also has good robustness for internal and external disturbances.
Dynamics Analysis of Carrier-based UAVs with Ski-jump Launch
Authors: Li Jixin , Liu Tao , Guo Hengguang
Published: November 2020

Sinking has a direct influence on launch safety of carrier-based UAVs, occurred just while leaving carrier board caused of disappearance of ground effect. A dynamics model of an UAV was developed and some mechanical and dynamics analysis were given out to build its dynamics simulation model of ski-jump launch. Based on the simulation results, some important parameters were analyzed, such as trace, velocity and loadings of landing gears. By changing the values of engine thrust and mass of the UAV, it was validated that decreasing the mass properly or increasing thrust would reduce the sinking and improve launch trace to make it safer.
Research on Development of Vehicle Chassis Dynamometer
Authors: Zhang Xiaorui , Zhou Zhili
Published: November 2020

Vehicle chassis dynamometer, as an important part of vehicle test equipment, plays an important role in the research and development of the vehicle’s entire life cycle. The development history of vehicle chassis dynamometer from hydraulic dynamometer to AC dynamometer was reviewed, and it was proposed that AC chassis dynamometer has become the mainstream trend. The vehicle chassis dynamometer was further discussed from the aspects of measurement and control system and road simulation system. On the basis of the current research status of dynamometers, based on the virtual test technology, network, intelligence and function expansion, the development direction and research focus of vehicle chassis dynamometers are given to provide reference for the further development of vehicle chassis dynamometers.
Bridge Damage Detection and Recognition Based on Deep Learning
Authors: Chen Xiuxin , Ye Yang , Zhang Xue , Yu Chongchong
Published: November 2020

Bridge damage detection is of vital importance to bridge safety. Nowadays the damage detection is mainly performed by human which is inefficient. We pro-posed a bridge damage detection and recognition method based on deep learning which is named DT-YOLOv3 in this paper. Our method is based on YOLOv3 object detection method and several improvements were made. First, deformable convolution was used to extract more accurate features, and transfer learning was introduced to improve the detection accuracy. Then, the model was compressed using group convolution and pruning. The test results show that our method is more effective than state-of-the-art methods and costs less time.