bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on Agricultural Production Efficiency of Lanzhou-Xi’ning Urban Agglomeration
Authors: Jun Luo , Xuebin Zhang 
Published: April 2020

Abstract
To clarify the efficiency and spatial-temporal characteristics of regional agricultural production is of great significance for adjusting the structure of agricultural production, improving the mode of agricultural production and coordinating the relationship between industries development. Based on the spatial constraints of the main function division, taking the counties providing agriculture products in Lanxi urban agglomeration as the basic research unit, using DEA model, we analyze the spatial-temporal characteristics, dynamic trends and the total factor productivity of the agricultural production efficiency from 2000 to 2015. The results showed that: 1. The overall agricultural efficiency of Lanxi urban agglomeration was very low and a few of regions were in the productive frontier, agricultural scale efficiency was greater than pure technical efficiency. 2. The spatial characteristics of the overall efficiency was “middle collapse”, while the pure technical efficiency and scale efficiency presented a gradient distribution pattern. The provincial differences showed that the overall agricultural efficiency and pure technical efficiency of Gansu Province were relatively high, while the opposite is true in Qinghai Province. 3. The overall TFP of agriculture was on the rise, and the overall efficiency improvement was shifted from the improvement of pure technical efficiency to the increase of scale efficiency. The TFP and its decomposition indicated that technological progress is the most important factor, which drives the rise of agricultural total factor productivity.
Swelling Behavior And Mechanical Properties In Filled Elastomeric Nano-Composites In Contact With Organic Solvents
Authors: Mdarhri A , Haouzi F El , Brosseau C , Aboudi I El , Bentoumi M , Azhari M EL 
Published: April 2020

Abstract
The effect of organic solvents on the transport process and mechanical properties in elastomeric nanocomposite materials is reported. The investigated samples are formed by a semicrystalline ethylene-co-butyl acrylate (EBA) polymer filled with hard spherical carbon black (CB) nanoparticles. The swelling behavior was studied at room temperature by immersion the dried samples in two selected solvents, i.e. toluene and xylene. The transport of the molecules of a given solvent in these filled elastomeric composites is found to follow a Fickian diffusion mechanism. Mechanically speaking, the stress-strain curves of uniaxial tensile tests pre-and post-swelling highlight a remarkably decrease of the Young’s modulus and strength of the swollen samples. This behavior can be attributed to the decrease of the load transfer density between the matrix and the CB in the presence of the solvent. The Mooney-Rivlin model is used to capture the physics of the stress-strain curves in both dry and swollen samples. The results reported in this experimental investigation can be useful for some demanding applications.
Non resonant Raman spectra of homogeneous and inhomogeneous individual dimers of Single-walled Carbon Nanotubes (SWNTs)
Authors: Boutahir M. , Abdelkader S.A. Ait , Fakrach B. , Rahmani AH. , Chadli H. , Rahmani A. 
Published: April 2020

Abstract
We study the effects of the coupling between single-walled carbon nanotubes (SWNTs) on the phonons in homogeneous (identical nanotubes) and inhomogeneous (different nanotubes) dimers of SWNTs. Bond polarization theory and the spectral moments method (SMM) are used to calculate the non-resonant Raman frequencies of the breathing-like modes (BLMs) and tangential-like ones (TLMs). The dependence of the phonons on different structural parameters such as diameter and chirality is investigated. We focus on the dependence of the so-called Breathing-Like Modes (BLMs) of dimers originating from the van der Waals coupling of the Radial Breathing Modes (RBMs) of each individual tube forming the dimer. On the other hand, the TLM of dimer is reported and discussed. Distinct behaviors of the TLM are evidenced. The calculated of spectra are compared with the few experimental Raman data obtained on individual dimers.
Wall thikness effects on the infrared spectra of multi-walled carbon nanotubes
Authors: Boutahir Mourad , Fakrach Brahim , Rahmani Abdelhai , Sbai Khalid , Chadli Hassan , Rahmani Abdelali 
Published: April 2020

Abstract
In this theoretical work, we investigate the infrared vibrational features of multi-walled carbon nanotubes (MCNTs). We calculate the polarized infrared spectra of multi-walled carbon nanotubes using the spectral moment’s method. This original approach allows us to consider MCNTs with a large number of walls. We discuss the evolution of the low, intermediate and high wavenumber regions of these spectra as a function of the inner diameter and the size of MCNTs. Both the XX and ZZ polarisations are considered. Our results provide benchmark theoretical data for understanding the experimental infrared spectra of MCNTs.
Investigation into Innovative Fabrication of Fiber Metal Laminated Pipe and Application
Authors: Zijian Lang , Meng Zhang , Xiaoxing Li 
Published: April 2020

Abstract
Fiber reinforced metal laminated tube (FMLT) is a kind of multi-layer super-hybrid material which is cured at a fixed pressure and temperature after alternately laying metal laminated tube and fiber composite material. The development of GLARE composite pipe hydroforming technology and performance testing is of great significance to the development of aviation industry and automotive industry in terms of lightweight and safety.
Numerical simulation of mesoscopic bubble defect and optimization of process parameters in fiber wetting process of high voltage post insulator resin
Authors: Yan B Y , Zhang Z , Yang W , Chu W , Yin L , Wang K , Dai X Y 
Published: April 2020

Abstract
Based on the method of fluid volume function, the two-phase flow model of mesoscopic resin and air between unit cell fiber bundles was established. The causes of mesoscopic bubble defects were discussed and the controllable process parameters were analyzed. A near-real mono-cell mesoscopic geometry model of strut insulator was constructed and meshed. The solution of the resin and air two-phase flow model was completed by adopting the finite volume method and using the Fluent software. The numerical simulation of the mesoscopic resin air two-phase flow and the air bubble defect was applied. The relationship between process parameters and air bubble defect was studied, and process parameters were optimized. Through the contrastive analysis of the capillary number, the correctness of the numerical simulation and parameter optimization was theoretically verified. Further, the effectiveness of the method in this paper was verified through the experiment.
Effect of Sputtering Conditions on Transmittance and Wear Resistance of Diamond-Like Carbon Film
Authors: Lai L F , Xu Z Y , Xu J 
Published: April 2020

Abstract
Diamond-like carbon (DLC) film was prepared by magnetron sputtering method on glass substrate. The microstructure, transmittance, and wear resistance of the diamond-like carbon film were investigated and analyzed. This study clearly showed the significance of sputtering power, Ar pressure and substrate temperature in controlling the transmittance and wear resistance of DLC film. The sp3 bond in the film had a greater impact on the transmittance and wear resistance of DLC film. The optimized deposition parameters obtained through experiments were: Ar pressure of 0.7 Pa, sputtering power of 100 W, and substrate temperature of 150 °C.
Research on tool path generation for integrated off-axis four-mirror group in single point diamond turning
Authors: Ning Peixing , Zhao Ji , Ji Shijun , Li Jingjin , Dai Handa 
Published: April 2020

Abstract
Multi-free-surface mirror integrated system is the development trend of optical system, but its ultra-precision machining is very difficult, this paper mainly studies the tool path generation problem of multi-free-surface reflector integrated system. In this paper, two tool path generation methods for the off-axis four-mirror group machining with SPDT are presented, one tool path generation method is separate machining and the other is integrated machining. Both methods are based on cylindrical spiral and generate tool path by projecting points onto surfaces. For the tool path generation method of integrated machining, the linear transition is used to realize the smooth transition of the mirror surfaces. By comparing the simulation machining of two kinds of tool path generating methods, it is found that the integrated tool path generating method is more suitable for off-axis four-mirror group machining and has higher machining efficiency.
The study on Reliability Design of Knotter Cam Gear of D-knotter
Authors: Cen Hai-Tang , Song Yu-Wei , Wei Rui-Tao , Li Ling , Qin Jian-Guo 
Published: April 2020

Abstract
The outer gear of knotter cam gear of D-knotter and pinion of knotter hook to achieve coordination and cooperation is important guarantee for the movement of “winding rope - biting rope”. This paper analyzes the damage mechanism of the outer gear of knotter cam gear. By application the probability theory for equal effect accuracy synthesis, the outer gear of knotter cam gear and pinion of knotter hook selected from 8 grade precision, and modification of teeth top along the normal direction of the measurement of 50.04 μm for pinion of knotter hook, can control the additional impact dynamic load less than 0.085 times of the calculated load. Two methods of traditional fatigue strength calculation and finite element analysis are used to check the strength of the incomplete outer teeth. And the results obtained by the finite element simulation described in this paper are closer to the real value. This study is of practical value in improving the reliability of the knotter cam gear and promoting the localization of D-knotter.
Stress State Measurement and Result Analysis of Car Wheels
Authors: Cheng Liu , Nianzu Ren , Qingsong Yang , Chao Chen , Cheng Tian , Zhengguo Liu 
Published: April 2020

Abstract
The stress state of the car wheel is one of the guiding design indicators for the wheel structure. This paper uses the combination of finite element method and bench test to study the stress state of the wheel when driving straight. Through the finite element simulation of bending fatigue and radial fatigue, the position of dangerous points during the use of the wheel is obtained. The location of the dangerous point is used as the strain measuring point, and the test bench is built. The strain gauge is used to measure the strain of these points in the straight running condition, and the test results are analyzed. The results show that when the vehicle is traveling straight, the tire will have a greater impact on the load of the wheel. The squeezing deformation between the tire and the wheel, as well as the positive and negative rotation, will have an effect on the stress state of the wheel. The maximum strain of the wheel appears on the inside of the wheel rim, the rim is in contact with the tire and along the circumference of the wheel. The strain near the center of the wheel is small. Different loads have no effect on the variation of wheel strain, but have an effect on the maximum and minimum peaks.
Static Simulation of Electric Tilting Tricycle Frame Structure Using The Finite Element Analysis
Authors: Muiz Mutqin Abdul , Jati Muhammad Kusuma , Cahyono Farras Prasrtyo , Sumarsono Danardono Agus 
Published: April 2020

Abstract
Electric Tilting Tricycle is a three-wheeled vehicle that has tadpole configuration driven by two sources of motion, that motion by a manual pedal and power from an electric motor. The three-wheeled vehicle has better stability and the tilting system improves ergonomics at curves. This research aims to design and analyze the strengths frame with three different materials using the Autodesk inventor software. By using the Stress Analysis feature that comes with the method of finite element analysis (FEA), we can know the result of von misses stress, displacement, strain, and safety factor. The main consideration of structural strength was seen from the distribution of static loads using three types of materials (Aluminium 6061, Steel Mild and CFRP). The minimum factor of safety resulting from the design simulation was estimated to be 1.83 using steel mild material.
Mechanical System Design and Simulation Research of a Demonstration Assembly Line
Authors: Ke MA , Yu Chen , Yi Sun 
Published: April 2020

Abstract
Most assembly lines use a bottom-up mechanical system design approach. In view of the problems of poor system interchangeability and low product versatility, a battery assembly line was designed based on the modular design method. The linear modules, cylinders and linear guides were used as the basic elements to build the production line modules. Different assembly requirements have improved the performance of the entire production line. The discrete-event system simulation method is used to simulate the quasi-running process of the production line, analyze the bottleneck of the production line, and improve the production efficiency of each module of the production line by changing the optimization method of the loading link and the production sequencing.
Research on water vapor measurement and removal methods for the spacecraft sealed cabin
Authors: Wu Yue , Guo Qingling , Yuan Weifeng , Xie Zheng , Wei Xi , Wang Jing 
Published: April 2020

Abstract
In order to develop a water vapor measurement and dewatering device suitable for ground test of spacecraft sealed cabin. A moisture measuring device suitable for the sealed cabin was designed. The existing moisture content measuring sensors were equipped with auxiliary devices to protect the electrical circuit of the sensor, and then the sensor was calibrated and analyzed. After calibration, it can meet the requirement of moisture measurement in vacuum environment. A small chamber was built to study water change rule in the pumping process. In the water removal system, the cabin was connected to the vacuum pump system through a two-way sealing flange, which can complete the water removal outside the vacuum chamber by pumping. When the pressure of the sealed cabin reached 100 Pa, high purity nitrogen gas was added to 97 kPa, then pumped in again. The results show that the water removal method can ensure that the dew point temperature of the sealed chamber is lower than 0°C during the vacuum thermal test. After protected, the dew point sensor can measure moisture at low pressure. The water removal system can effectively remove the moisture in the sealed cabin, thus ensuring the completion of the vacuum thermal test.
Design and Numerical Simulation of a High Speed Centrifugal Compressor
Authors: Yu Qingyang , Wu Peng , Deng Yelin 
Published: April 2020

Abstract
The issue of energy consumption has attracted worldwide attention, therefore the performance requirements of rotating machinery are getting higher and higher in modern commercial run. Active magnetic bearings have the advantages of high speed and low friction, so they are widely used in high-speed rotating machines such as high-speed centrifugal compressors. A stage of impeller and diffuser was designed. Numerical simulations of the flow field were performed using CFX. The pressure and velocity field in the model stage (impeller and diffuser) were obtained and analyzed. The results show that the model stage has uniform velocity field distribution and regular flow field, and the performance parameters can well meet the industrial requirements.
Analysis of manhole structure Safety of draft tubes in hydropower plant
Authors: Li Wenbo , Zhang Jun , Liu Lanlan , Li Xiaokai , Wang Jun , Zhou Hengyi , Xie Yi 
Published: April 2020

Abstract
The fault of the manhole on draft tube in a hydropower plant was investigated and analyzed. The results showed that the main reason for the cracking and leakage of the manhole on draft tube was that: the four corners of the manhole were not rounded, so fatigue cracks appeared under the effect of long-term alternating loads, which caused the leakage at the four corners of the manhole on draft tube during unit operation.
Case analysis of mechanical maintenance supply scheme based on NSGA-II algorithm
Authors: Xia Wei , Shi Quan , Wang YaDong 
Published: April 2020

Abstract
Based on the maintenance strategy of mechanical equipment, the mechanical maintenance supply scheme is designed and studied. Combined with a specific case, the intelligent optimization algorithm is used to solve the model, and a series of Pareto optimal scheme sets are obtained. Compared with other classical intelligent algorithms, the effectiveness and robustness of the algorithm are verified.
Numerical analysis of the effect of turbulence on particle agglomeration
Authors: Zhang Weikuo , Liu Guanqing , Zou Chongen 
Published: April 2020

Abstract
The turbulent agglomeration characteristics of a mechanical elements were investigated by numerical simulation using the SST k-ω model. The vorticity field, turbulent dissipation rate and pressure drop in the flow field were obtained. The results show the bluff body flow phenomenon occurs when the incoming flow passes through the spoiler element. On the back of the element, a periodic vortex similar to Karman vortex street is formed. After the airflow passes through the turbulence element, the turbulent dissipation rate in the main flow area is higher, and the particle agglomeration effect is significant. In the vortex street period, due to the viscous dissipation, the dissipation rate decreases exponentially with the increase of the propagation distance, and the agglomeration effect decreases. Due to the resistance of the turbulence element, the pressure drop between the inlet and outlet is up to 143pa, resulting in a large pressure loss.
Study on Prediction of Binder Distribution in the Drying Process of the Coated Web of Positive Electrode for Lithium ion Battery
Authors: Su Yongjian , Zhou Kai , Yuan Yingchun , Liu Weiwei , Deng Yelin 
Published: April 2020

Abstract
The slow and high energy consumption of drying process of the coated web of positive electrode for automotive lithium ion battery have become the bottleneck in the manufacturing process of cathode coating. However, high drying rate of solvent (commonly N-Methyl-2-pyrrolidone (NMP)) result in higher concentration of binder (commonly polyvinylidene fluoride (PVDF)) at the evaporating surface than at the bottom. The uneven distribution of binder between coating layers will lead to the decrease of adhesion between active layer and substrate, and even an increase in internal resistance and the associated deteriorated rate capability, thus seriously damaging the mechanical and electrochemical properties of the electrode. In order to improve the drying efficiency of the coated web, and regulate the concentration distribution of binder, this study mainly calculate the evaporation rate under different drying parameters. and determine the binder distribution at the different evaporation rates.
Application of High-Speed Photography in Amplitude Measurement of a Satellite Antenna
Authors: Liu Zhibin , Sun Gang , Wang Yu , Du Ruizhao , Liu Zhe 
Published: April 2020

Abstract
Spacecraft antenna is an antenna loaded on the spacecraft and an indispensable part of the spacecraft system. It is particularly important to measure the assembly accuracy of the antenna. A certain type of satellite needs to test the amplitude of antenna A and B in sinusoidal vibration test. Because the distance between antenna A and antenna B is very close to the fairing, it is necessary to measure the amplitude of antenna A to verify the spatial compatibility of antenna A with carrier fairing and antenna B in the test process. By comparing four kinds of antenna measurement technology, this paper chooses high-speed photography technology to measure the amplitude of the antenna, uses recognition processing computing technology to binarize the image, changes the image into calculable coordinate value, obtains the amplitude data of X-direction and Y-direction, and verifies the space composite compatibility requirements between antenna A, carrier fairing and antenna B under vibration conditions. There will be interference and collision.
Wall-climbing obstacle-avoiding full-automatic lampblack cleaning device
Authors: Qin Jiarui , Wei Qian 
Published: April 2020

Abstract
With the development of Chinese society and the progress of productive forces, dust and oil stains are easily produced in kitchens and ceilings when living at home. Dirt deposition in many places cannot be carried out well due to the limitation of space location and cleaning methods, which brings great inconvenience to people’s life. At the same time, the existing cleaning robots in the market need to work on a single wall surface, and when encountering obstacles, the positions of the robots need to be adjusted manually to further realize the work and cannot solve the cleaning problems of ceilings and the like. The existing cleaning robots mostly use centrifugal fans to fix on vertical wall surfaces in an adsorption way, thus causing obstacles to be avoided, the connection between different wall surfaces cannot be realized, and the defect that intelligence works on a single wall surface requires manual wall surface replacement, thus reducing automation, intelligence and intelligence. Based on the above background, the members of this group have designed a wall-climbing cleaning machine. The device mainly comprises a walking module, a wall turnover module and a cleaning module [1].
Optimization of extended range electric vehicle energy management strategy via driving cycle identification
Authors: Chen Yong , Zhang Yue , Wei Changyin , Li Guangxin , Li Congcong 
Published: April 2020

Abstract
There are ambitious fuel consumption targets for the manufacturers of heavy-duty vehicles. For this reason, extended range electric vehicle (EREV) is a promising powertrain technology. However, the energy management strategy (EMS) is still an obstacle to the improvement of fuel economy. This paper introduces an energy management strategy for driving cycle identification. Twenty-two typical driving cycles are divided into five categories through Q-type clustering. Euclidean distance is used to identify the driving cycle. For each type of driving cycle, the energy management strategy parameters are optimized through genetic algorithms with fuel consumption and emissions as the goals. The results show that the EMS via driving cycle identification is more effective than a strategy that does not identify it. For comprehensive test cycles, the former’s fuel consumption is optimized by 6%, SOC consumption is optimized by 1%, and there is a slight improvement in emissions.
A momentum-based method for the mass concentration measurement of pneumatically conveyed solid: design optimization
Authors: Liu Guanqing 
Published: April 2020

Abstract
Mass concentration measurement of pneumatically conveyed solid is still challeging in industry. In our previous work (Liu G.Q., The 5th International Conference on Advances in Energy Resources and Environment Engineering, December 6-8, 2019, Chongqing, China.), a novel momentum-based method with more reliable measurement mechanism and simpler structure was developed and computationally validated with a one-end closed straight tube. In this paper, optimization on the structure of the metering tube is conducted to improve the measurement sensitivity represented by the conversion factor k. Tubes with a conical inlet are found to possess higher k than that of the straight tube. Computational fluid dynamics (CFD) computations show that k generally increases with decreasing half-cone angle at fixed radius and decreases with decreasing restitution coefficient of collision between particles and the tube walls.