bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.