bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of annealing temperature on the microstructure and optical properties of MoS2 films
Authors: Zhang Bianlian , Cheng Zhen , Meng Yu 
Published: August 2020

Abstract
In this paper, MoS2 films were prepared on silicon and glass substrates by RF magnetron sputtering. The surface morphology, structure and transmission and reflectivity of MoS2 films were characterized by SEM, XRD and spectrometer. The effect of annealing temperature on the properties of MoS2 films was analyzed. The results show that the annealing temperature has an obvious effect on the surface morphology of MoS2 thin films, and different annealing temperature can change the position of XRD diffraction peak of MoS2 thin films. The higher the annealing temperature, the better the growth quality and the higher the transmission and reflectivity of MoS2 film.
Preparation and characteristics of Co nanoporous magnetic materials synthesized by a template-free method
Authors: Kong Jing , Li Yan , Gao Hong , Wang Xiangke , Yu Xiangtian , Yao Ziyang , Wang Fenglong , Liu Jiurong 
Published: August 2020

Abstract
We report a template-free hydrogen reduction approach to prepare cobalt nanoporous magnetic materials with various morphologies employing Co3O4 as precursors, which were obtained by thermal-decomposing CoCO3 intermediates. The kinetic control of experimental parameters of synthetic CoCO3 intermediates by a facile solvent-thermal route can be an effective strategy to tune the morphology of Co nanoporous structures. The microstructures, crystal structures or thermal characteristics of products at different stages were investigated to reveal the formation mechanism of the Co nanoporous structures. Magnetic measurement showed that the Co nanoporous structures with rhomb-like and prism-like morphology exhibited saturation magnetization (Ms) of 149.2 emu/g and 141.8 emu/g, and coercivity (Hcj) of 508.4 Oe and 554.9 Oe, respectively. The as-prepared Co ferromagnetic materials exhibited remarkably high coercivity values mainly due to the three dimensional nanoporous structures.
Application of PVC-melamine-formaldehyde resin composite in drug adsorption
Authors: Qi Boyi , Yang Qinghao 
Published: August 2020

Abstract
A new technique for the synthesis of melamine-urea-formaldehyde (MUF) resins was explored in conditions of normothermia.The MUF and common UF resin were analyzed by FTIR.The effects of activation time,pH on the adsorption performance (expressed by the adsorption capacity of Norfloxacin hydrochloride(NOR)) were investigated. The adsorption process of nonresident for Norfloxacin hydrochloride using batch technique was optimized by different parameters including pH, stirring time.The optimum stirring time was 180 min,the adsorption process was favored in acidic medium rather than alkaline one. The equilibrium data were fitted by the Freundlich and Langmuir isotherm models and the adsorption process fitted well with the linear Langmuir isotherm and pseudo- second order kinetics.
Research on the preparation and properties of biodegradable wood-plastic composites
Authors: Ge Zhenghao , Li Xiaoqian , Si Dange 
Published: August 2020

Abstract
In this work, the PLA/PBS/straw powder wood-plastic composite were fabricated by injection molding process. Special attention was paid to the effects of different parameters of injection molding process on the mechanical properties of the wood-plastic composite. The optimum injection molding process parameters of wood - plastic composites were determined by orthogonal experiment. According to the optimal injection molding process parameters, biodegradable wood-plastic composites filled with different compatibilizers were produced. The effects of MAPLA, silane and combination treatment on the interface compatibility and mechanical properties of the wood-plastic composite were investigated by scanning electron microscope and mechanical properties test. The results showed that the combination of the two compatibilizer treatments can improve the interface compatibility of wood-plastic composites, but the improvement of it mechanical properties is not obvious. The mechanical properties of wood-plastic composites were optimiz when the content of MAPLA was less than 5%.
Experimental analysis of damage mechanism and shrinkage performance of recycled concrete
Authors: Liu Ying , Du Tianling 
Published: August 2020

Abstract
This article analyzes the interface structural features and damage mechanism of recycled aggregate concrete. Recycled aggregates are divided into three types by particle shaping. Through the experiments, the shrinkage performance of recycled concrete is analyzed under the conditions of different cement content and the replacement rate of recycled coarse aggregate. The experimental results show that A is the worst, inferior to NA ordinary concrete; C is the best, superior to NA ordinary concrete.
Effect of different micro-texture shape on corrosion resistance of metal surface
Authors: Xu Rui , YongshengWang  , Wang Yipu , Wang Zhankui , Su Jianxiu 
Published: August 2020

Abstract
The 304 stainless steel is widely used in daily life. In this paper, the 304 stainless steel was taken as the substrate material and then the five different micro texture shapes were carved on them by nanosecond laser engraving machine under the same parameters. These shapes are the groove array, the square column array, the circular pit array, the regular hexagon column array and the trapezoid column array. Then these samples were immersed in 0.5mol/l perfluorodecyl trimethoxysilane ethanol solution at 45 °C for 5 hours. Five type super-hydrophobic surfaces were obtained. A series of corrosion experiments were conducted out and the influence of different micro texture on the corrosion resistance to the 304 stainless steel surface was analyzed. The results show that the square column array has the best corrosion resistance, and its corrosion rate is4.20mm.a−1, which is the lowest in all other micro texture shapes. It can be used as a reference for improving the corrosion resistance of metal surface.
Synthesis and fluorescence properties of dansyl labeled triazine dendrons
Authors: Li Long , Cheng Rong-chao , Ma Cha , Hao Hui-jun , Li Li-hua , Zhao Zhi-liang 
Published: August 2020

Abstract
A series of fluorescent dendrons with dansulfonyl group as a fluorophore attached at the focal point were synthesized by a convergent method. There was no need for tedious and lengthy protection/deprotection or chromatographic separation. The method provided simple operation and high yield. Their fluorescence characteristic in dichloromethane was investigated. The results indicated that the dendritic modification had positive effect on the emission of fluorescence, and the emission maximum of dansylated dendrons was enhanced up to 20-fold. Meanwhile, the fluorescent intensity of dansylated dendrons could be remarkably improved with the increase of dendron generation. These findings can contribute significantly to the general understanding of the dendron systems and also for potential applications in photochemical molecular devices and organic electroluminescent devices.
Coupled simulation for reentry ablative behavior of hypersonic vehicles
Authors: Mei Zongshu , Shi Chengying , Fan Xueling , Wang Xiaobin 
Published: August 2020

Abstract
Numerical analyses of hypersonic vehicles ablative behaviors focus on the accurate models of the thermochemical reaction flow field. The assumptions of chemical equilibrium and non-catalytic wall cannot meet the ablative behavior prediction requirements for high Mach number flights with multiphase materials. In this paper, the numerical analysis of hypersonic vehicle reentry involves the nonequilibrium thermochemical flow field and thermodynamic structure with moving boundary. Two surface models, finite rate catalysis model and Park finite rate surface interaction model were applied into the flow field simulation. And the reentry ablative behaviors of two hypersonic vehicles were simulated by the partitioning methods using the computational fluid dynamics code Fluent and the material thermal and structural response code Abaqus with user defined codes. And the two codes were loosely coupled in time to exchange the data. The structural temperature, surface shape change at the wall under different reentry altitudes and various angles of attack were obtained. The validity and reliability of frame work set up were validated with previous work.
Research on the effect of vibration of aerial cameras on imaging quality under flight conditions
Authors: Lin Jieqiong , Guo Xin , Gu Yan , Gao Minghui , Zhang Hanyuan 
Published: August 2020

Abstract
In order to make the structural design of the aerial camera meet the requirements of the imaging system, the influence of externally excited vibration interference on the imaging quality of the aerial camera optical system under the flying state of the UAV was studied. This paper adopts the optical-machine integrated analysis method (OIAM) to cause the vibration interference influence is studied. The MTF (modulation transfer function) is used as an evaluation index of imaging quality. The aerial camera dynamics simulation analysis is performed to extract the displacement of each node under vibration excitation. The lens deformation is fitted using the Fringe Zernike polynomial. The obtained data were used for optical performance evaluation. The analysis have showed that the optical system of the aerial camera has a 0.071% reduction in the MTF at a resolution of 91 lp / mm under the excitation of flight vibration, with little effect.
Application of tractor virtual test technology in product innovation design
Authors: Yan Xianghai , Zhou Zhili , Li Zhongli 
Published: August 2020

Abstract
As a necessary link for product development and evaluation, tractor testing covers new technologies in multidisciplinary fields and plays an important role in the research and development of product life cycle. This study discusses the research status of tractor test and evaluation technology and analyzes the new technology associated with the test and evaluation technology. Aiming at the problem of poor reusability, poor interoperability and weak expansion of the current tractor virtual test model, a virtual tractor-based test technology based on the architecture was proposed. The middleware technology, test data management technology, modeling technology and test environment construction technology in the tractor virtual test system were analyzed. Taking the tractor power shift transmission as an example, the application of the architecture-based virtual test system was verified, which pointed out the direction for the design verification of tractor innovative products.
Comparison and application of two time domain methods analysis to modal parameter identification of Songhuajiang River highway-railway bridge
Authors: Jin Bo , Zhu Chuankai , Yu Kunyang , Li Zhongwei , Bai Yu 
Published: August 2020

Abstract
In this paper, comparison and application of two time domain modal parameter identification methods of ERA and SSI in a steel truss bridge is discussed. Firstly, multidirectional comparison and analysis of structural modal parameter identification under environment excitation to the bridge are carried out. Then finite element model of the Songhuajiang River highway-railway bridge is established by MIDAS CIVIL, and the modal analysis of the structure is carried out. The first ten order modes of the structure are obtained, and some characteristics of the first ten order modes are analyzed and compared. And combining the partial trend of the finite element modal analysis, the vibration experiment of the Songhuajiang River highway-railway steel bridge under the environmental excitation is tested. Then the modal parameters of the structure are calculated, analyzed and compared through the ERA method and SSI method based on the state space model. Finally the accuracy of the two modal parameter identification methods is tested, and the feasibility of the two methods applied in the steel truss bridge structural analysis is verified.
Radius survey of crawler crane base on total station
Authors: Xu Haixiang , Qiu Jun , Wu Fengqi , Xue Jiai 
Published: August 2020

Abstract
The process of surveying crane parameters has been continually refined due to the competitive situation, modern surveying instruments and more powerful softwares. As the radius is the crucial parameter to determine the jib crane’s safety, a survey scheme is put forward to solve the problem that the rotary axis can’t be determined on-site in the paper, which measures the coordinate data of marked points by utilizing the total station, then the plane fitting method and the space analytic geometry method are adopted to determine the revolving centre axis. The proposed method is simple and easy to implement with acceptable accuracy in the field.
Study on the collaborative design architecture of tractor performance prototype
Authors: Wu Yiwei , Zhou Zhili 
Published: August 2020

Abstract
The tractor performance prototype characterizes the multidisciplinary performance properties of tractor and plays an important role in the iterative upgrade process of new product performance. In order to meet the needs of collaborative development for tractor new products, the functions of distributed design and remote interconnection, and the performance verification of product system-level design, this paper analyzes the tractor collaborative development organizations and functions from the tractor performance prototype collaborative design theory. The performance prototype collaborative design process model is established with UML, and the design supporting environment characteristics are extracted. On this basis, a collaborative design architecture is constructed, and the key technologies which include the collaborative modeling and simulation, tool integration, data management and resource platform construction are proposed and analyzed. Through the preliminary study on the collaborative design architecture of tractor performance prototype, this paper aims to provide the theory and technical mode for developing the tractor digital, networked and intelligent design system.
Research on train fingerprint positioning based on LTE-R signal strength
Authors: Luo Miao 
Published: August 2020

Abstract
Being aimed at improving the low accuracy when using WKNN location fingerprint based on LTE-R signal strength value, CPSO algorithm, for its advantage, is applied to optimize the weight. CPSO_WKNN location fingerprint positioning algorithm is proposed to solve the train position coordinates.Through verification by cases, WKNN weight optimized by CPSO algorithm and PSO algorithm are separately analyzed and compared, which proves that CPSO optimizes the weight of WKNN algorithm with faster convergence speed. By fingerprint spacing every 25m, 50m, and 100m, the positions of the train in tunnel environment are solved separately by CPSO_WKNN location fingerprint positioning, PSO_WKNN location fingerprint positioning and WKNN location fingerprint positioning. The simulation results show that the positioning accuracy increases with the decrease of the fingerprint spacing for any of the three positioning methods. Under the same fingerprint spacing and the same accuracy demand, the accuracy level of CPSO_WKNN location fingerprint positioning is the highest. When fingerprint spacing is 25m and CPSO_WKNN location fingerprint is applied, the probability of positioning error less than 10m is 87.8%, and the probability of positioning error less than 25m is 96%, which can meet the demand of high-precision positioning in tunnel environment.
Research on intelligent vehicle trajectory tracking based on model predictive control
Authors: Fang Yongshou , Cheng Jin , Lv Minyu 
Published: August 2020

Abstract
Intelligent vehicle trajectory tracking lateral control is the key technology to realize intelligent driving. Aiming at the problems that the existing control methods have a small effective control area and poor control effect under cornering conditions or small road adhesion coefficients, a model predictive control (MPC) algorithm is proposed for trajectory tracking control. Based on the two-degree-of-freedom vehicle model, a state space equation is established and discretized to obtain a predictive model that meets the conditions. Then, the corresponding objective function is designed based on the ideal yaw angular velocity under the optimal preview control theory, and the input-output constraints and side-slip angle constraints are designed according to the control and state quantities. The controller model is established in MATLAB / Simulink, and the road model is built in CarSim for joint simulation. Compared with CarSim’s own algorithm, the changes in side acceleration and steering wheel angle are smoother and less oscillating. The maximum lateral deviation and lateral acceleration are also smaller, and the lateral stability of the car is improved. It has better adaptability on pavement with lower adhesion coefficient, and can also maintain control stability. The real vehicle test results are consistent with the simulation results, with a maximum lateral error of 0.44m and a maximum heading angle deviation of 1.43 °. Therefore, the trajectory tracking control algorithm based on model predictive control designed in this paper has significantly improved control accuracy and stability, and can maintain control stability even when the road surface adhesion coefficient is low.
A HMM-based and multi-indicator driven network model for complex electromechanical system reliability analysis with considering reliability fluctuation
Authors: Li Jiwu , Gao Zhiyong , Wang Rongxi 
Published: August 2020

Abstract
In this paper, a new network model is developed for better expression of the interaction of a complex electromechanical system. The developed model can reflect the current reliability fluctuation followed by system state disturbances. The Failure Mode and Effect Analysis (FMEA) data and indicator data from detection and monitoring is collected and processed for the structure and parameters of this network model. Hidden Markov Model (HMM) is used for transforming indicators into the probability of fault causes. The recorded fault statistic data is considered as the prior knowledge, and the current indicator data can be used to renew the prior probability of component failure and system malfunction. With this model, the current component failure probability and system malfunction probability can be obtained.
Pole assignment PID controller based on parameter identification and its application
Authors: Lu Tong , Wu Ruliang , Zhang Jun , Liu Shouwen , Hu Fang , Guo Jiacheng 
Published: August 2020

Abstract
In order to ensure spacecraft qualification before the delivery, thermal tests should be performed with regard to its performance specification. The aim of thermal tests is to examine the function and performance under extreme thermal and vacuum conditions, and also to detect possible manufacturing defects or check the rationality of theoretical thermal models[1]. Temperature control of spacecraft products is one of the critical tasks in the thermal test, which has the characteristics of large thermal inertia and time-delay. Ordinary single control method often leads to poor performance or even out of control[2]. In this paper, the model of control object is identified by the least squares recursive algorithm (LSRA). According to the identified parameters and the expected pole position, three parameters of the PID controller are obtained. In order to test the control effect of this control method, representative test data is selected for simulation analysis, and the simulation effect is satisfactory. Then this control method is applied to temperature control of satellite solar array of Chang’E-1. The results show that pole assignment and the self-tuning PID controller based on parameter identification has the advantages of strong adaptability and high control precision.
Fully-digital tension control system with PID algorithm for winding ultra-fine enameled wires
Authors: Gu Zhewei , Zeng Sheng , Zhao Kaijie , Song Chenliang 
Published: August 2020

Abstract
An active fully-digital tension control system with PID algorithm is proposed. Only digital signals are involved and processed throughout the closed-loop control system, which employs the micro-controller unit (MCU) dsPIC33EV256GM102 as the main controller with PID algorithm, incremental photoelectric encoder as the angular sensor and AC servo motor as the actuator. A rod-spring mechanism is indispensably constructed to convert the change of tension to the variation of rod’s swing angle. Characteristics of the controlled object are tested and analyzed, from results of which the mathematical model is theoretically deduced. The PID coefficient set is determined by Ziegler and Nichols method. Its practicability is initially validated in simulation using SIMULINK/MATLAB. The prototype is also fabricated and experimented on with ultra-fine enameled wires (0.08mm). In order to enhance the practical performance, PID coefficients are further adjusted in experiments. The results show that the proposed system performs well both in transient process and steady stage. Meanwhile, it has good anti-interference capability as well.
Numerical control press design based on quantitative evaluation of appearance area features
Authors: Yuan Hao , Wu Tong , Li Mingzhu , Liang Boke , Zhang Qinglin 
Published: August 2020

Abstract
The appearance characteristics of numerical control presses were quantitatively evaluated using eye-tracking technology, and a numerical control press design method was proposed to provide guidance for the design of such mechanical products. By investigating and analyzing the appearance of numerical control presses locally and abroad, the modeling characteristics of these products are summarized. The interest areas of the press are divided using the hot zone map data of the eye movement experiment, and people’s knowledge of each area of the press is quantitatively analyzed. Data generated by multiple eye movement experiments are combined with a subjective questionnaire to identify the mechanics of the press. The front and work areas are the main features of the press design. Based on the experiment result, the press design is conducted based on color and modeling elements. We used the Jiangsu CPTEK numerical control press as the actual case. We also re-matched the color, optimized the details, and developed an improved design scheme, thus verifying the proposed design method.
Fault diagnosis method of rolling bearing based on the multiple features of LMD and random forest
Authors: Liu Ning , Liu Bing , Xi Cungen 
Published: August 2020

Abstract
The occurrence of rolling bearing fault not only affects the operation efficiency of mechanical equipment, but also leads to the safety accidents. The research on fault diagnosis of rolling bearing is of great practical significance to improve the reliability of mechanical equipment, avoid unexpected faults and ensure safety in production. In this paper, a fault diagnosis method of rolling bearing based on the multiple features of local mean decomposition (LMD) and random forest is proposed. It is suitable for processing non-stationary vibration signals generated by rolling bearings and adaptively decomposing the characteristic information excited by faults into a series of product function (PF). Then, the mixed feature vectors of each PF are constructed from different angles to realize the extraction and quantification of the rolling bearing fault feature information. Finally, combined with the random forest algorithm, accurate identification of the type of rolling bearing failure is achieved. The overall recognition rate reached 94.4%. It proves that the method proposed in this paper is effective.