bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructure evolution and residual stress changes of the GH4169 alloy by wet shot peening
Authors: Zhou P F , Zheng H Z , Guo S H , Cheng S P , Li G F
Published: August 2019

GH4169 alloy was shot-peened with processing durations of 3 min and 10 min. The effects of dry and wet shot peening on the microstructure and residual stress were investigated. The results demonstrated that a severely deformed layer manifests on the surface of the shot-peened GH4169 alloy samples. Compared with the dry-peening samples, the surface defects of wet-peening samples obviously decrease. With the shot peening treated for 10 min, the surface microhardness of the dry peening and the wet shot peening increased by 20% and 17% respectively compared with the original surface hardness. The deformation mechanisms of the GH4169 alloy could be attributed to dislocation and deformation twining, as detected by TEM observations. Compressive residual stress was introduced into the surface layer of the shot-peened GH4169 alloy. The maximum surface residual compressive stress (SRS) and maximum residual compressive stress (MRS) were -586 MPa and -795 MPa, respectively. The MRS and SRS were improved with increasing processing duration. The SRS of the wet-treated specimens was slightly higher than that of the dry-treated samples under the same processing parameters. However, the MRS of dry-treated samples was much larger than that of the wet-treated samples due to the higher shot intensity.
Plasma treated MXene/Ag-based humidity sensor with ultrahigh sensitivity for gesture tracking
Authors: Liu Hui’an , Li Ning , Jiang Yue , Wang Qiang , Peng Zhengchun
Published: August 2019

A novel humidity sensor based on MXene (Ti3C2) combined with Ag nanoparticles was prepared in this paper. Owing to high surface-to-volume ratio and outstanding hydrophilicity of sensing film, the humidity sensor shows ultrahigh sensitivity. Moreover, this kind of sensor exhibits fast response speed which can detect human breath. Meanwhile, with a 7×7 sensor array, hand gesture can be tracked without direct contact of these sensors by hand which provides an unique approach for human–machine interaction without using machine vision.
Novel Bromide Quaternary Ammonium Ligand for Synthesizing High Fluorescence Efficiency CsPbBn Perovskite Quantum Dots and Their Fabrication of White Light-Emitting Diodes with Wide Color Gamut
Authors: Xie Qifei , Li Yue , Min Xianhao , Ma Yanhong , Wang Xinzhong
Published: August 2019

We proposed a novel bromine quaternary ammonium ligand to synthesize high quantum yield (QY) CsPbBr3 quantum dots (QDs). The QY of CsPbBr3 QDs synthesized by this ligand reached 95% and the full width at half maximum (FWHM) was as narrow as 17nm. The peak wavelength of the prepared CsPbBr3 QDs was 530nm. And these QDs emitted high purity green light under ultraviolet light. The color coordinate of white LED (WLED) prepared with the CsPbBr3 QDs was (0.29, 0.31), which was very close to pure white light. The color gamut of the WLED covered 130% of the national television system committee (NTSC) color standard and 96% of the ITU-R Recommendation BT.2020 (Rec.2020) color standard.
A Robotic arm based automatic solar-tracking system
Authors: Ju Huimin , Xin Shubiao , Shen Yaoxin , Li Xianglong
Published: August 2019

The automatic sun-chasing panel can effectively improve the utilization of solar energy by adjusting the robotic arm that keep a right angle towards the sunlight. The new tracking system searches the position of the sun by analyzing the video stream captured by the camera and then binarization and edge detection methods are adopted to prevent the interference of other light sources. In the contemporary world with the shortage of energy resource, automatic sun-chasing panels can effectively improve the utilization of solar energy, so that the photoelectric conversion rate stays at the peak at every moment, effectively alleviating the problem of energy shortage.
Fault Diagnosis of Gear Pump Based on Sparse Representation
Authors: Zhiyin Han
Published: August 2019

A fault diagnosis algorithm of gear pump based on sparse representation is proposed in this study. The vibration signals of the faulty gear pumps are different from those of the normal ones. Therefore, by comparing the vibration signal of an unknown gear pump with the training signals form the normal gear pumps, its fault can be analysed and identified. The sparse representation is used in this study and the vibration signal of the test sample is linearly represented based on the dictionary formed by the normal signals. When the reconstruction error is large enough, the present gear pump is judged to be faulty. Otherwise, it is a normal one. Experiments are conducted based on some measured vibrations signals from both faulty and normal gear pumps. The results show the effectiveness of the proposed method.
Analysis of production decline factors of fracturing horizontal wells in tight reservoirs and study of decline law
Authors: Chong Zhang
Published: August 2019

Horizontal well fracturing technology has been applied in tight oil reservoirs, and most horizontal wells show decline after high production period. In order to define the change law of horizontal well production based on the geological and engineering factors on the influence of the horizontal well production change, the paper uses Daqing region A block of the horizontal well production data in view of the analysis of the regressive method. Based on the analysis of each decline method, it is considered that the horizontal well production in this block is the exponential decline, which lays a foundation for the prediction of horizontal well production and the adjustment of the later development system.
Investigation on the Thermal-Mechanical Treatment of 2A12 Al-Alloy during Spinning Process
Authors: Dongpo Wang , Wenlong Zhao , Shicheng Ma , Yuyi Wang , Yueqian Zhang , Ang Sun
Published: August 2019

Combined with the spinning process of cylindrical parts, the thermal-mechanical treatment of 2A12 Al-alloy was discussed in detail in this paper. Effects of deformation amount and aging temperature on the mechanical properties of 2A12 Al-alloy were analyzed based on extensive experimental results, which further provided an optimized choice of thermal-mechanical treatment parameters for practical production, and served as reference in spinning similar products.
Structure design of InGaAs quantum well laser with mode expansion layer Lei
Authors: Gu Lei , Yuan Huibo , Li Lin , Zhang Jing , Li Zaijin , Zeng Lina , Qu Yi , Ma Xiaohui , Liu Guojun
Published: August 2019

InGaAs quantum well (QW) is grown on GaAs substrates by metal-organic chemical vapor deposition (MOCVD). The effects of growth temperature and V/III ratio on the optical properties are discussed by analyzing the photoluminescence(PL) measurement at room temperature. It is found that the PL intensity of the QWs grown at low temperature is stronger, and the luminescence intensity of the samples can be increased by increasing the V/III ratio of the QW. Crosslight software is used to simulate the laser structure with mode expansion layers. Compared with conventional lasers, it’s demonstrated that inducing the mode expansion layer would expand the near-field, reduce the confinement factor, improve the catastrophic optical damage (COD) threshold of the laser, and reduce the vertical divergence angle of the far-field.
The Practice and Safety Security of the whole Marine Diesel Engine on Maritime Transportation
Authors: Cheng Zhaoxi , Zhang Tianyu , Fan Yaotian
Published: August 2019

In order to effectively mitigate risks and improve the safety of whole machine transportation at sea, it is necessary to study the safety of the maritime transport of the whole machine. The safety of marine diesel engine transportation is discussed in this paper, with company management, ship type selection, ship management and actual operation.
High conversion efficiency and extra-cavity sum frequency 355nm UV laser output
Authors: Wang L , Jin G Y
Published: August 2019

Currently, the common method to obtain ultraviolet laser is an all-solid-state laser combined with nonlinear frequency conversion technology, which generates three, four or five harmonics outside or inside the resonator cavity through the frequency conversion of near-infrared light waves around 1.0μm. Ultraviolet light sources are mainly obtained in two bands of 355mm and 266nm. Ultraviolet laser is characterized by high photon energy, short wavelength, cold treatment and good focusing performance, be widely used in the fields of medicine and biology, industrial microprocessing, atomic/analytical spectroscopy and chemical dynamics, environmental detection and atmospheric detection. In this article, we put forward with two sum frequency crystals to obtain UV laser, based on the method of theoretical analysis and experiment validation, Nd:YAG crystal was used as a gain medium to generate 1064 nm laser, double frequency generated 532 nm green laser by KTP crystal, 1064 nm and 532 nm throughed two sum frequency crystals and frequency conversion outside the cavity. The High conversion efficiency and high peak power 355nm ultraviolet light output is realized.
Research Status and Engineering Application of Magnetorheological Elastomers
Authors: Ren Zhong , Zhang Tieshan
Published: August 2019

Magneto-rheological elastomer is a new type of magneto-rheological material characterized by controllable reversibility of rheological properties and very short response time. Moreover, the stability is good and the structure design is simple, so it has broad application prospects in the fields of intelligent vibration reduction and noise reduction, electromagnetic sensors and active control. The research status of magneto-rheological elastomers at home and abroad is introduced systematically, including the mechanical model of magneto-rheological elastomers, magneto-mechanical properties, influencing factors and engineering applications, and several problems that should be further studied in the future are proposed.
Research on Small Size Thread Torque Coefficient with Assembly Pressure
Authors: Zhang Zhijing , Cui Can , Jin Xin , Wang Zifu
Published: August 2019

Threaded connection is one of the most commonly used methods in product assembly. The stability of the joint quality has a great impact on the performance of the product. At present, research on threaded connection rarely considers the influence of assembly pressure. This paper proposes a method about small size thread torque coefficient test that takes into account the assembly pressure. The small size threaded connection test device was developed by our lab. The law of dynamic torque coefficient under different assembly pressures can be got to guide the quantitative control of small-size thread pre-tightening force.
High precision and fast solution method for linearized assembly contact point of geometric error surface
Authors: Liu Zhihua , Zhang Zhijing , Jing Xin , Zhang Weiming , Wang Zifu , Shang Ke
Published: August 2019

The geometric error modeling method for assembly[1] proposes a feasible basis for the assembly process considering manufacturing error. However, contacting two mounting surfaces with geometric error and finding their actual contact points are two main difficulties in the study of real three-dimensional parts assembly methods. A high-precision and fast solution method for linearized assembly contact points considering geometric errors is proposed by calculating the point cloud spatial pose of the actual contact surface. This method is suitable for spatial pose calculation in high precision plane assembly of rigid parts, which enables fast, accurate and quantitative solution of the positional relationship of components during assembly and measurement, and improves the accuracy and efficiency of spatial pose prediction and control.
Feasibility and structure analysis of gas/electric dual power vehicle power system
Authors: Liu Haiyan , Dai Peng , Li Xuewei
Published: August 2019

In this paper, based on the design requirements of gas/electric dual power vehicles on the basis of the completion of the experimental car power matching, including the prime movers selection and check, including: focus on the analysis of compressed air power as a gas/electric dual power vehicle power source feasibility, and the experimental vehicle power system design and selection; In this paper, the layout of two power sources of the vehicle is analyzed, and the characteristics of several forms are discussed in the test vehicle. Under this research scheme, the control strategy of the vehicle in starting, light load, heavy load, climbing and other working conditions is discussed and compared.
Research on Automatic Processing Code Generation System Technology of Micro-Turning and milling combined Machine
Authors: Jin Xin , Liu Biao , Zhang Zhijing , Zheng Zhongpeng
Published: August 2019

Turn-milling machine tools have significant advantages in the machining of high-precision small-size parts. Currently, due to the small size and complex structure of the parts used in the turning and milling machine, manually programmed processing code is inefficient and some automatic generation of processing code software steps are complex and lacking in specificity. Based on a self-developed turning and milling machine, this paper establishes a software framework for such CNC machine tools with automatic generation of NC code as the main function line. We simultaneously design and analysis of specific interface development to provid the software part support for the processing code generation of intelligent processing equipment.
Simulation Study on Regenerative Braking System of Pure Electric Vehicle with Compound Power Supply
Authors: Gang Li , Hao Lin , Rongxia Xu
Published: August 2019

In order to enhance the recovery rate of regenerative braking energy on the premise of ensuring braking safety and stability, an improved braking force distribution scheme for front and rear wheels is proposed in combination with ECE regulations, ideal braking force distribution curve (I) and f lines. Meanwhile, a kind of fuzzy controller is designed, which takes the braking strength, vehicle speed and super-capacitor SOC as input and the ratio of regenerative braking force to total braking force of front wheels as output. The forward and backward simulation module is established in MATLAB and embedded into ADVISOR. In addition, combined with the secondary development of the top layer model of the compound power supply for pure electric vehicle to complete simulation and analysis under the CYC_UDDS driving cycle condition. The results show that the regenerative braking control strategy can improve the recovery rate of braking energy and increase the driving mileage of pure electric vehicle.
The ADAMS kinematics optimization simulation of the twin-motor spiral pair direct-driven press
Authors: Jia Xian , Zhao Yi , Lei HongChun , Zhao Lu
Published: August 2019

With rapid development of global manufacturing industry, the demand for stamping parts has increased greatly. In order to meet the requirements of high precision and low cost, famous manufacturers have adopted direct-driven presses as the focus of technology development. In this paper, the drive system’s mechanical structure of the twin-motor spiral servo direct-driven press based on the principle of the electric spindle is designed, and the kinematics model of the press is established. Using ADAMS software to simulate the stamping and engraving functions of the press, the motor is simulated at the rated conditions, the motion curve of the slider is simulated, and the electronic rated power and rated speed of the press are checked; The work process of stamping and engraving is optimized, and the optimized slider motion curve is calculated and compared, which provides a good foundation for the development and promotion of the twin-motor spiral pair direct-driven press.
Analysis of Anti-jet Penetration Characteristics of Axial Single-cell / Multi-cell Closed Structure
Authors: Changxing Zhao , Fucheng Yin
Published: August 2019

To analyze the mechanical properties of jet penetration on a single-cell / multi-cell liquid composite closed structure, the motion equation of jet penetrating a metal target is established, and the energy equation of the penetration system is derived. The simulation results show the radial convergence effect of the liquid in the single-cell increases with the increase of the height of the inner cavity of the closed structure. The radial convergence effect of liquid in multi-cell also has the same phenomenon, but the phenomenon of liquid disjunction appears, which leads to the convergence of liquid into segments. The pressure in the single-cell liquid appears at the bottom of the cell, but the multi-cell liquid appears in the last cell. The pressure distribution of the single-cell is concentrated on the bottom of the cell, and the pressure distribution is circular. The pressure distribution of multi-cell is more uniform, and there is no obvious concentrated distribution phenomenon. The energy of the closed cell structure increases with the increase of the height and the number of the cell.
The effect of inner assisted gas length on the gas-assisted extrusion forming of plastic micro-tube
Authors: Ren Zhong , Huang Xingyuan
Published: August 2019

The effect of inner assisted gas length on the gas-assisted extrusion forming of plastic micro-tube was numerically studied in this paper. The 2D geometric models with different lengths of inner assisted gas were established. Under the same boundary conditions and material parameters, the profile changes of extruded plastic micro-tubes were obtained. To ascertain the reasons of profile changes induced by different lengths of inner assisted gas, the radial and axial flow velocities, shear stress and the first normal stress differences of melt were all obtained. Numerical results show that the diameter swell or shrinkage phenomenon occurs when the inner assisted gas length mismatches the outer assisted gas length. The deformations are generated by the unbalance axial flow velocity of melt induced by the mismatch of two assisted gases lengths, especially at the outlet of assisted gases. At the same time, the shear stress focus and first normal stress difference focus of melt are also existed at the outlet of assisted gases. In practice, the lengths of two assisted gases should be equal in the gas-assisted extrusion of plastic micro-tube.
Theoretical analysis and experimental study of a perforated piezoelectric cantilever
Authors: Su Huaiwei , Sui Li , Song Ping , Lu Yousong
Published: August 2019

Piezoelectric energy harvesters have been studied extensively because they show considerable promise for use in both military and commercial applications. In order to improve the output capability of the piezoelectric energy harvester, the perforated piezoelectric cantilevers were designed in this work. To study how the hole on the cantilever affected the output characteristics, this paper analysed the position and size of the hole separately. The results show that, perforating the cantilever can cause stress concentration of the piezoelectric cantilever, and improve the output capacity.
A Flexible Connection System for Manipulator
Authors: Hao Yongxin , Li Jianxiang , Wang Haipeng , He Feng , Hu Xuran
Published: August 2019

At present, the intelligent inspection robot of substation can carry infrared thermal imager, visible camera and other related detection devices of power plant equipment, relying on magnetic navigation or laser navigation, along the established route of substation to achieve the detection of outdoor equipment. With the continuous deepening of the application of substation inspection robots, some higher requirements are put forward for the application of robots. How to complete the detection of indoor switchgear in substation by robots has become a key research direction in the industry.
Study on Application of New Kinetic Energy Theorem of Rigid Body Fixed-Axis Rotation
Authors: Yang Yong
Published: August 2019

The classical kinetic energy theorem of rigid body fixed-axis rotation cannot correctly reflect non-conservative force doing dissipative work, non-conservative reacting force doing equivalent dissipative work at the same time, instead convert the system’s mechanical energy into the non-mechanical energy of the bearer. Now these defects are overcome by the new kinetic energy theorem of rigid body fixed-axis rotation.The meaning of new kinetic energy theorem of rigid body fixed-axis rotation is interpreted, the procedures to solve practical problems on new kinetic energy theorem of rigid body fixed-axis rotation and computing methods of the terms in the new kinetic energy theorem of rigid body fixed-axis rotation are studied, as well as the physical significance of the results is described.
Experimental Study of Cortical Bone Microstructure and Its Toughening Mechanism
Authors: Wang Xiaohan , Li Dongxu , Hao Rui
Published: August 2019

With the increasingly severe mechanical environment of the planetary detectors, fracture and failure are more likely to occur at their load-bearing structures. Therefore, it is urgent to improve the toughness of load-bearing structures. Because of the unique microstructures, goat tibia has remarkable toughness. In this investigation, firstly, the cortical bone of goat tibia was observed by SEM, and the characteristic microstructures were identified. Secondly, the cross section of cortical bone was loaded by long-term inplane stress, then the toughness of cortical bone in different regions were obtained based on the orientation and distribution of cracks after the load. Finally, the toughening mechanisms of cortical bone were discussed. This study of the cortical bone toughening mechanism can be helpful for the biomimetic design of high-toughness materials.
Intelligent Assessment of 95598 Speech Transcription Text Quality Based on Topic Model
Authors: Song Bochuan , Wu Peng , Zhang Qiang , Chai Bo , Gao Yuanbo , Yang He
Published: August 2019

The quality of speech transcripts is of great significance to power system management and is an important basis for supporting subsequent data analysis. In this paper, based on the characteristics of speech transcription texts of customer service, this paper proposes an analysis method combining manual processing and latent Dirichlet allocation topic model, analyzing the transcribed texts. First, data preprocessing is performed on the State Grid’s work order data, and then the text topic distribution calculation is performed by the LDA topic model, and the topic parameter is set to a total of 100 topics. Next, the unsupervised clustering of the documents is performed by the k-means method, and the similarity between the files is obtained. Finally, the quality of the data is analyzed by combining manual labeling and manual evaluation. For the first time, this paper marks and identifies the State Grid’s work order analysis data, which is a pioneering work for natural language processing technology in the field of power grid.
Design and implementation of three-dimensional model for medical image of bone defect
Authors: Feng B H , Cai W W , Zhou P E , Luo J X , He H F , Peng L F
Published: August 2019

Bone defect caused by trauma and tumors is an important problem to be solved in orthopaedic clinic. Bone defects caused by various reasons have different shapes. In this paper a model of bone defect was created by 3D printing technology, which was tailor-made for doctors to simulate the bone defect before operation. Firstly, CT files of bone defect were imported into the Mimics medical image control system, then the pathological model was formed by image processing and three-dimensional reconstruction. Secondly, the 3-matic forward engineering software was ultilized to realize the design model of bone defect repair by describing, mirror image and bone repair. Thirdly, after processing the design model with Cura chip software, the PLA macromolecule material was used to make the physical object by 3D printer. By researching the design method, forming quality, printing speed, structure and performance parameters, researchers explored the manufacturing technology of 3D printing products for bone defect.
Dynamic Guidance Sign Design for Passenger Transfer in City Railway Hubs
Authors: Wang Bo , Zhang Wenbin
Published: August 2019

The congestion state models are established for three traffic modes of city railway hubs. According to visual and psychological characteristics of passengers, a new dynamic guidance sign system is designed to release transfer information. The identification and continuity level of information on guidance signs are evaluated to make the design more reasonable. The research would provide a new design and evaluation method for transfer information guidance system in city railway hubs.
Research on the Difficulty Points Marking System of Online Learning Process
Authors: Daxiong Luo , Zhujun Ye , Yi Yu , Xiaoli Zhao
Published: August 2019

There exists a notable problem in MOOCs that teachers can’t find the difficulties during the learners’ learning process because of their inefficiency of supervising the learners’ real learning status. To solve this problem, we model the learning behavior of online learners based on facial expression information and mouse track data, and propose a method for marking learner’s difficulties in online learning process based on machine learning. At same time, we design and implement a prototype system for marking difficulties based on our method. Experiments show that our method can improve the efficiency and quality of marking learner’s difficulties effectively.
Construction safety education system based on virtual reality
Authors: Bin Feng , Xi Zhao , Yi Chen , Ping Wang Gui
Published: August 2019

In view of the shortage of traditional construction safety education in China, this paper introduces virtual reality technology into the field of safety education. The virtual reality construction safety training system designed allows multiple experiencers to be physically, visually and tactfully present at the same time. In the virtual scene of construction accident safety hazard, the experiencer completes the consciousness migration that corresponds the virtual scene to the real scene, thereby avoiding the safety accident in the real construction and maximizing the safety education effect. The overall architecture of this work includes the virtual reality system and the vibration system. The scene model in the virtual reality system is mainly 3D modeling with 3Dmax, and the Unity game engine is used for animation and interaction design. Because the system is mainly for traffic construction and construction units, the design scene mainly includes three major parts: bridge construction scene, road construction scene and tunnel construction scene. The vibrating system is designed to enhance the virtual experience. The system communicates with the host to acquire the corresponding vibration signal and drive six low-frequency vibrating horns, so that the experiencer have a strong sense of vibration.
A Study of the Chinese spam Classification with Doc2vec and CNN
Authors: Gong Hechen , You Fucheng , Wang Shaomei
Published: August 2019

Convolution neural network is a kind of neural network, which has been proved to be very effective in image recognition and classification. In recent years, convolution neural networks have gradually shifted to the field of natural language processing and become one of the research hotspots. For the construction of word vector text using convolution neural network, only considering the relationship between word granularity level, not considering the relationship between words, nor considering the relationship between semantics, affecting the classification results. In this paper, a method based on Doc2vec and CNN is proposed to classify spam. Firstly, the spam is preprocessed, then the sentence vectors and word vectors of Chinese text are trained by Doc2vec, and finally the trained text vectors are classified by convolution neural network.
Design of Marine Automatic Leakage Stoppage System Based on Artificial Eddy Current
Authors: Xin Guipeng , Cheng Zhaoxi , Gao Chengfeng
Published: August 2019

This paper analyses the problems existing in the traditional methods of blocking leakage of ships, breaking through the ideological framework of “blocking” only. The design of ship automatic leak stoppage equipment based on artificial eddy current is put forward, and the experimental verification is carried out. The whole leak stoppage system is designed from the idea of automatic control. The experimental results show that the method can greatly reduce the pressure of seawater on the break and the water inflow per unit time by artificially forming local high-speed eddy flow field at the appropriate position outside the break, thus creating favorable conditions for the plugging of the break in the cabin. The research conclusion can enrich and perfect the method of blocking leakage for ships.
Promoting the Leadership of Grass-roots Party Organizations in the Strategy of Rural Revitalization in the Big Data Era
Authors: Liao Xiaodong , Liu Xiaoping , Feng Feng
Published: August 2019

The report of the Nineteenth National Congress of the Communist Party of China emphasizes the role of grass-roots Party organizations as fortresses. In the era of big data, when implementing the strategy of rural revitalization, new requirements are put forward for grass-roots Party organizations in underdeveloped areas. Grass-roots Party organizations are also facing the dilemma of weak political leadership, inadequate capacity of Party members and cadres and dilute Party-masses Relations. In order to solve these difficulties, we need to strengthen the political function of grass-roots party organizations, strengthen the construction of Party members’ talent team, and increase the mass line education practice activities to enhance the leadership of grass-roots party organizations.
Distributed Topology Identification Information Model of Distribution Network Based on IEC61850
Authors: Zheng Ganyun , Xu Qifeng , Wang Dujing , Xie Nan
Published: August 2019

This paper proposes a distributed topology information model based on IEC61850 to support the distributed topology processing function of the distribution network automation system. The information model expands the new logical nodes and common data classes for storing local topology information of local subgraphs and communication information of adjacent intelligent electronic devices. By using the distributed adaptation of graph connectivity algorithm and the extended IEC61850 information model, the dynamic topology identification function of the distribution network structure is realized. The extended information model and topology recognition algorithm are verified by the cyber-physical simulation system.
Parametric Sensitivity Analysis of Automobile Radiator Performance
Authors: Bargal Mohamed H.S. , A. Abdelkareem Mohamed A. , Wang Yiping
Published: August 2019

The automotive radiator is an important part for automotive engines regarding its direct influence on the thermal performance of the engine. This paper presents a theoretical parametrical sensitivity analysis of an automotive radiator based on the effectiveness-NTU method. In this manner, the paper firstly focuses on the influence of operating conditions of both the water and air including inlet temperatures and Reynolds numbers on the radiator effectiveness, heat transfer rate, and the pressure drop. Furthermore, the sensitivity of the radiator responses versus these operating conditions is provided. Given the obtained results, it is concludingly reported that the radiator effectiveness correlates significantly to the water Reynolds number and the water inlet temperature rather than its correlation to the air Reynolds number and air inlet temperature. While the heat transfer rate correlates strongly to the inlet temperatures of the water and air, respectively, while the heat transfer rate weakly responded to the Reynolds numbers of the water and air. On the third hand, the water pressure drop presented higher sensitivity change at lower water temperatures.
Study on Dimension of Landing Gear Bogie for Civil Aircraft
Authors: Li Zhongjian , Mu Tengfei
Published: August 2019

In order to study the method on rapid design of bogie dimension for aircraft landing gear, the paper firstly clarifies the dimension definitions of landing gear bogie, then proposes four kinds of constraints which have influence on determination of landing gear bogie dimension: expanded-tire dimension limit, clearance requirement, flotation characteristics requirement and bogie accessories dimension requirement. These four kinds of constraints form an area where can be selected to define the bogie dimension during aircraft initial design phase.
Compilation technique of outside fillet macro program
Authors: Wang Shuai , Zhao Xueqing
Published: August 2019

With the popularization of software automatic programming, the application of macro program has become the greatest advantage of manual programming. In fact, macro programs have irreplaceable advantages in the processing of specific geometric shapes. Combining with the most common Siemens subsystem in the world, this paper expounds the programming skills of the outside fillet macro program. Three layers of nesting, i.e. main program nesting subroutine and re-nesting subroutine, are used to compile the outside fillet macro program. It has been widely applied in practical machining.
Impact Path on the Development of Railway Freight Transportation Services by Informatization Based on Sector Perspective
Authors: Jin Zongzhen , Cao Lili , Cheng Yonghong
Published: August 2019

The effect of informatization and standardization on civil aviation, waterway transport and highway transport is analyzed respectively, which finds the informatization is embedded the freight standard. Information has played the important role in the improvement of the freight efficiency and service quality in three transport sectors. Learning from the above experience, some suggestions on informatization-driven quality improvement in railway freight transportation services are given below to promote the transformation of railways into a modern logistics system, to develop the mechanisms and systems that meet the requirements of market economy for railway transportation management, and to establish modern logistics enterprises.
Design, Simulation and Fabrication of a Time-Delay Device Based on Micro-Channel
Authors: Zhao Qiaoran , Sui Li , Song Ping
Published: August 2019

With the development of micro-machining technology, the application of microchannel is becoming more and more popular. In this paper, we design a set of time-delay device based on micro-channel and micro-fluidics technology. This paper describes the time-delay device’s working principle and analyses the micro-channel’s flow characteristics by simulation method based on Coventerware. From studies on the micro-channel’s cross section, geometry and dimension parameters, the micro-channel’s optimal form and dimension can be obtained. Finally, this paper chooses ultra-machining process to fabricate the time-delay device.
Intelligent Analysis Method of Assembly Process Based on Semantic Elements
Authors: Du Zenghui , Liu Jianhua , He Yongxi
Published: August 2019

The assembly process file is a direct expression of the product assembly design intent. In order to improve the quality and efficiency of the assembly, the 3D model of the product and resources needs to be introduced into the virtual assembly environment. However, the assembly process is verified and optimized by assembly simulation. In order to realize the intelligent analysis of assembly process files and the automation of assembly simulation, an intelligent analysis method of assembly process based on semantic elements is proposed. This article takes the assembly process documentation of complex products as the research object. An improved TF-IDF algorithm is proposed to automatically extract key semantic elements in the assembly process file. We quickly resolve previous assembly process data by building assembly key semantic corpora. An assembly semantic dependency tree algorithm based on maximum entropy is proposed to automatically reason the logical relationship of each assembly phrase in the assembly process statement. According to the above algorithm, the assembly semantic intelligent analysis system is developed. The assembly process of a certain type of ground weapon system is taken as an example to verify the system. And the intelligent analysis of the product process file is realized which lays a foundation for realizing the semantic driving of product assembly simulation.
Design of a reciprocating freight ropeway in mountain orchard
Authors: Guiju Fan , Fu Qin , Tiantao Feng , Hao Zhang , Zhao Li
Published: August 2019

Aiming at the problem of high labor intensity in field transportation of fruit in mountain orchards, a single-span reciprocating ropeway transportation system was put forward according to the topographic characteristics of mountain areas and the income of fruit farmers. The ropeway transport system consists of an electric winch, two pillars on the left and right, a circulating traction wirerope, a track rope, wind cables, a sports car, and tensioning mechanisms. Through analysis and calculation, steel wire ropes with diameters of 12mm and 6mm are used as track rope and traction rope; electric winch machines with power of 1.5kW and reduction ratio of 15 are selected, and the friction reel diameter is 200mm. Finally a single-wheeled sports car is designed to ensure the normal transportation of the ropeway.
Research and Application of Laser Ranging Method in Form and Position Tolerance of Precision Machining Products
Authors: Ouyang Hongmei , Zhou Mingyao , Gao Lei , Wu Yu , Yang Li , Li Jieji
Published: August 2019

Precision measurement of shape and position tolerance plays an important role and significance in manufacturing industry. It is an important link to measure and guarantee the quality of manufacturi ng. Especially for large-scale precision parts, the repeated use of measuring tools easily leads to measurement errors. Aiming at the problems of low detection efficiency, complex process and high cost of high precision three-coordinate measuring instrument for large-size parts, the characteristics of contact measurement and non-contact measurement for large-size parts are studied based on the characteristics of large-size parts. A measurement method combining laser ranging with reflective target is proposed, and a rotating shaft for fixing laser launcher is designed. A complete spherical coordinate measuring system is constructed, which is applied to the measurement of straightness, flatness, parallelism, verticality and height difference of large-scale precision machined parts. The corresponding measurement results are obtained in a constant greenhouse. On this basis, under the same temperature conditions, the same shape and position tolerance dimensions of the same part are measured by a three-coordinate measuring instrument. Comparing the results of measurement, it can be seen that the measurement results obtained by the two methods are the same in the range of 0.001 mm, and the measurement efficiency and cost of the laser ranging method have obvious advantages. This paper also gives the method of measuring the shape and position tolerance of large-scale precision parts.
Design and application of robot welding station for BTE
Authors: Yang Qinglong , Qi Baoyun , Mao Qinjian , Wang Ten
Published: August 2019

The battery tray enclosure (BTE) is an important part of new energy vehicles, and has high requirements on quality, strength and heat dissipation. Considering the function of the BTE, the characteristics of the welding process and the specialty of the tooling system, a BTE robot welding workstation was developed by integrating the fusion welding technology, weld seam tracking technology, sensor technology and machine electrical integration engineering technology. The one-time fully automatic welding of the frame tray improves the working environment, reduces labor intensity and the welding skill requirements, and avoids poor quality such as less welding, leakage welding, and poor consistency due to manual welding.
Design and experimental performances of a piezoelectric stick-slip actuator for rotary motion
Authors: Ding Zhaochen , Dong Jingshi , Yin Haojie , Wang Zhe , Zhou Xiaoqin , Xu Zhi
Published: August 2019

In order to reduce the regression phenomenon of the piezoelectric stick-slip actuator, and improve the output performance, a piezoelectric stick-slip actuator with regular octagonal flexible hinge mechanism is proposed in this paper. The pseudo-rigid body method is used to analyze the regular octagonal flexible hinge mechanism and the flexible driving foot respectively.A prototype is fabricated to test the working performance and the results demonstrate that the minimum step is 0.01μm, the maximum speed is 145251μrad/s, and the maximum load carrying capacity is 500g. The experimental results show that the parasitic motion suppresses the regression of the actuator and improves the output stability.
Research on counter-roller spinning force based on finite element simulation and experiment
Authors: Guo Yaming , Li Mingzhe , Huang Tao , Wang Dali , Zheng Hongwei , Luo Wei , Li Yinan , Gao Wulin , Zhao Xing
Published: August 2019

Counter-roller spinning is an effective method for forming large metal cylindrical parts. In this paper, the radial, axial and tangential counter-roller spinning forces were analyzed. The simulation analysis model was established and the counter-roller spinning was simulated based on the commercial FEA software, SIMUFACT-FORMING. The influence of different thinning ratio, feed rate and forming angle of roller on spinning force was analyzed. It can be seen that the deviation between the simulation average radial spinning force and the experiment average radial spinning force was less than 12%, and that of the axial spinning force is less than 10.5%, which can effectively guide the spinning process test.
Bonding Heating Control Based on PID
Authors: Yu Ye
Published: August 2019

In the process of chip production, the bonding machine, as the post-process of chip manufacturing, is a key process to determine the chip productivity and quality. The process of wafer bonding usually involves heating silicon wafer, glass backing and other materials to a certain temperature in a vacuum environment, applying a certain pressure, and bonding for a certain period of time. In the bonding process, the time to heat the material to the specified temperature accounts for about 20% of the whole bonding process. Therefore, shortening the heating time has a great effect on improving the yield. In addition, in the process of heating and pressure, improving the heating stability, reducing the temperature oscillation, can reduce the material deformation and improve the bonding accuracy. In this paper, the intelligent temperature control system based on PID is adopted to control and adjust the bonding heating in real time, so as to shorten the heating time, reduce heating control oscillation, improve the heating effect, and improve the yield and yield.
Status evaluation of smart substation measurement and control device
Authors: Min Zhang , Jian Shen , Li Chen , Bin Zhou , Liang Zhou Shao , Zhe Hou
Published: August 2019

In power system, measurement and control device plays an important role in maintaining an ideal level of reliability. Therefore, the reliability of the measurement and control device should be evaluated to fully understand the cause of its failure. A new evaluation model is proposed, which relates the fault of measurement and control system with the four main reasons of device hardware fault, software fault, auxiliary equipment fault and human fault. In addition, the model can also comprehensively consider other aspects of the measurement and control system, such as human error in testing and software upgrade, effectiveness of daily operation monitoring, degree of dependence on self-inspection, local backup and misoperation. These studies have a lot of significance to the reliability of the control system, and also can effectively improve the stability of the system.
An Observer-Backstepping Robust Controller Design Method
Authors: Li Zhen , Chen Xin
Published: August 2019

Unmodeled dynamics and external disturbances are the main factors affecting system performance. In this paper, a robust design method based on backstepping control and observer is proposed to overcome the problem of the system unmodeled parts and external disturbances. To improve the performance, the controller uses adaptive function to eliminate the effect of the unmodeled dynamics. For the external disturbances, this paper using observer to accurately estimated and effectively compensated. The simulation results show that the controller designed in this paper has good performance and can accurately response the input commands in the case of the unmodeled part of the system and the external disturbance.
Research and Design of Theme Image Crawler Based on Difference Hash Algorithm
Authors: Wang De-zhi , Liang Jun-yan
Published: August 2019

For the problem of high repetition rate of image resources collected by general theme crawler, a theme image crawler system is designed to reduce image similarity. The main contents of the design include the main function modules of the crawler, the workflow of the system and the implementation method of the key modules. The difference hash algorithm is used to solve the problem of image similarity effectively. Combined with Web text cosine correlation algorithm and link PageRank algorithm, the paper comprehensively evaluates the relevance between Web resources and topics. The experimental results show that the subject image crawler can effectively reduce the similarity of the collected images and improve the efficiency of crawler image resources acquisition.
Prediction of Building Power Consumption Based on GAWNN
Authors: Yaqing Tian
Published: August 2019

With the continuous development of urban modernization, the power consumption of building is increasing rapidly. In the context of the basic national policy of sustainable development, energy conservation and emission reduction of building energy consumption is imperative. In this paper, the relevant influencing factors of building electricity consumption are considered comprehensively. The wavelet neural network combined with genetic algorithm is (GA-WNN) used to predict the power consumption of buildings. The experimental results show that the prediction effect and relative error of GA-WNN algorithm are better than other prediction methods. The unique advantages of the algorithm in the field of building power consumption prediction can provide a scientific basis for energy saving and consumption reduction. It can facilitate managers to formulate efficient energy management solutions to optimize resource allocation.
Design of Belt Conveyor Speed Control System of “Internet+”
Authors: Li Zhiqiang , Zeng Fei , Yan Cheng , Wang Junjie , Tang Ling
Published: August 2019

In this paper, a belt conveyor speed control system based on “Internet +” is designed by using the embedded web and single-chip microcomputer. By monitoring the running state of the belt conveyor, adjusting the speed between the two stages of the belt conveyor, real-time monitoring of the speed between the two stages of the belt conveyor, and two levels of the difference between the speeds is used as the input parameter of the speed control PID algorithm to achieve a smooth transition between the two stages of the belt conveyor. The system has the advantages of strong expandability, strong portability, high efficiency and environmental protection.