bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acoustic emission properties of different mineral admixture concrete
Authors: Li Jiapeng , Qin Lei , Sha Pingping , Sun Shidong 
Published: October 2019

Abstract
To study the different mineral admixtures on the mechanical behavior of concrete, in this paper, three groups C20 concrete cubes made of different mineral admixtures were cast. The size of the cubes are all 150×150×150mm. Acoustic emission by uniaxial compressive test to study the different mineral admixtures on concrete mechanics performance and acoustic emission parameters (amplitude, energy, frequency) were studied. The results show that the addition of mineral powder to the concrete surface will increase the compressive strength of the early age (before 56d). Adding fly ash to the concrete will increase the compressive strength of the late age (after 90d). By combining fly ash and mineral powder, the compressive strength and durability can be better improved; and as the age goes by, the acoustic emission amplitude and dominant frequency of different mineral admixture concretes are increased. The dominant frequency of the compound concrete is greater than the dominant frequency of the single concrete.
Effect of pit detail morphology on fatigue characteristics of LD2CS aluminum alloy
Authors: Yan Guangyao , Liu Zhiguo , Mu Zhitao , Li Xudong , Liu Tao 
Published: October 2019

Abstract
LD2CS aluminum alloy is an important structural material for a certain type of aircraft in coastal service. In order to assess the fatigue mechanical properties of LD2CS aluminum alloy materials in the coastal airport environment, accelerated pre-corrosion fatigue test of LD2CS aluminum alloy specimens in the laboratory environment is required. Through the study of the surface morphology of LD2CS aluminum alloy specimen and fatigue fracture observation,it is found that with the increase of the number of year of the equivalent accelerated corrosion in advance, internal corrosion pit morphology is complicated, and the crack initiation corrosion pit roots are often more strident. the root radius depth ratio of corrosion pit η is defined, it is found that after equivalent accelerated pre-corrosion 7 years, when η ∈ (0,0.4], the corrosion pit is easy to become the key pit which could initiate the dominant crack. The equivalent crack for the key pit was quantified by η, and the fatigue life of the equivalent crack was predicted by the Forman formula, which was in good agreement with the life test value of LD2CS aluminum alloy specimen. It shows that the equivalent crack method considering the details of the pit root is of high engineering practical value and can provide more powerful data support for the aircraft damage tolerance analysis.
Solvent-Controlled Cascade Reaction of Ugi/Pd-Catalyzed Intramolecular Divergent C-H Functionalization for Regioselective Synthesis of Cyclopropanated N-Heterocycles
Authors: Shang Tianyi , Pan Yan , Chen Zhong , Yang Junjie , Guo Xinling , Guo Leilei , Liu Yan 
Published: October 2019

Abstract
A novel cascade reaction of Ugi/Pd-catalyzed intramolecular divergent C-H functionalization, which is controlled by solvent effect to achieve the regioselective synthesis of spiro- and fused-cyclopropanated indolines from the Ugi adduct of N-acylated 2-bromoarylamides.
Experimental Study on Optimization of Culture Medium and Culture Environment of Bacillus Megaterium
Authors: Ming Sui , Zhang Yang , Tao Ruixiao , Xiao Nianle , Zhou Wen , Rong Jiachao , Zhou Rongqing , Li Guoying 
Published: October 2019

Abstract
The medium components and culture conditions were investigated through orthogonal test. The experiment showed the optimum fermentation medium (g/L) was composed of peptone 10, beef paste 6, yeast extract 6, sodium chloride 7, agar 15,PH=8.0; The suitable culture conditions were as follows:culture temperature was 30 °C, rotating speed was 200r/min,liquid level was 60mL/250mL,inoculation volume was 5%. Bring up under the optimal conditions, using tablet coating method, the optimum fermentation time was 48h, the number of viable cells reached the peak 2.52×108cfu/mL, at this time.
Mathematical modeling and optimal operation condition analysis of heat pump two-effect direct contact membrane distillation system
Authors: Liu Ronghui , Chen Dong , Peng Yuelian , Xie Jihong , Jin Cheng 
Published: October 2019

Abstract
Compared with traditional membrane distillation system, the heat pump two-effect direct contact membrane distillation system has an advantage of low energy consumption. However, affected by many kinds of parameters, such as materials, components and operation conditions as well as the complex coupling between these parameters, it is difficult to achieve the optimal operation conditions and high gained output ratio (GOR) by optimizing the parameters. Therefore, analyses of mathematical modeling and optimal operation conditions of heat pump two-effect direct contact membrane distillation system were carried out in this paper. According to the operating principle and physical characteristics of key components, such as membrane distillation system, heat pump system, intermediate heat exchanger and auxiliary cooler, the mathematical model of heat pump two-effect direct contact membrane distillation system was established, the process of system performance simulation was designed and system performance simulation software was compiled to analyze the effect of ten parameters on GOR and total water production(Wtot). The optimal operation conditions analysis method of heat pump two-effect direct contact membrane distillation system was proposed. Through the developed simulation software of the heat pump membrane distillation system, using the proposed optimal operation conditions analysis method, When Wtot was 10.0kg/h and heat pump compressor power was 688W, the GOR of the optimized system could reach 9.43
Research on The Whole Teaching Process Evaluation and Quality Assurance System of Higher Vocational Colleges
Authors: Hu Xiaoming , Su Yunfeng , Wang Ting 
Published: October 2019

Abstract
We study the whole process evaluation and quality assurance system of higher vocational education. This paper focuses on introduces the research of quality standard system in the whole process of teaching, the whole process evaluation of teaching, and the whole process of teaching TQM (Total Quality Management). Through research, we can find out the key issues affecting the quality of teaching, when “Total Quality Management” is applied in the field of higher vocational education, we must look at all the work of the school from the perspective of service, and the school should establish a “quality system” to continuously improve the quality of education. The whole teaching process monitoring and quality assurance process is a complex system. When there are problems in the whole process of Higher Vocational teaching, we can find out the solution to the problem or a permanent solution through research. In order to improve the quality of teaching in Higher Vocational schools, we must implement total quality management. We hope to establish and perfect the quality standard system of “school, enterprise and society” which covers the quality standards and work norms of all teaching links, Establish a quality monitoring mechanism for enterprises to participate in the whole process, strengthen the process monitoring of teaching quality management, absorb the employer’s participation in teaching quality evaluation, improve the teaching quality information feedback system, and build a perfect monitoring and evaluation system. Construct a set of teaching quality assurance system with the college as the core, the education administrative department to lead, and the society to participate.
Explicit Dynamics Simulation of High-Speed Railway Bearing Based On ANSYS/LS-DYNA
Authors: Wang Yongwu , Zhang Gang , Ma Canyang , Yang Kai , Zhang Zhenqiang , Ren Zhongming 
Published: October 2019

Abstract
A solid model of a high-speed train axle box bearing was built by using 3D modeling software. On the platform of ANSYS/LS-DYNA, the combined dynamic and finite element analysis method is used to apply the combined radial and axial loads to the high-speed rail bearing. In order to demonstrate the dynamic contact characteristics of the bearing during operation, two operating conditions were designed. One is running at a uniform speed in a straight line, the other is running at an assumed speed with a minimum turning radius. The results show that the stress distribution, velocity and acceleration of bearing components under two different working conditions are obviously different. The research can provide reference for the design, selection and optimization of domestic high-speed rail bearings.
Study of the Process Parameters of the Laser Stereo Forming on Forming Quality
Authors: Maa Wanli , Tao Fenghe , Jiab Changzhi 
Published: October 2019

Abstract
Based on the supply problem of the equipment spare parts in the poor timeliness and the low accuracy during the wartime, this paper studies applying the laser stereo forming technology in the weapon parts for the supply. The 316L stainless steel is selected as the printing material in the experiment. And based on the control variable method, it takes the three major parameters of the laser power, the scanning speed and the powder feeding rate as variables to study the influence on the rule and mechanism of the processing parameters on macro forming quality. The results show that the height decreases with the increase of the laser power and the scanning speed, and the height increases with the increase of the powder feeding rate. The width is basically unchanged, which is mainly affected by the size of the spot.
Analysis on The Assembly Technology of Manned Spacecraft and Unmanned Spacecraft
Authors: Du Ruizhao , liu Zhibin , Dai Hailin , Wang Pengfei 
Published: October 2019

Abstract
The aerospace machine contains manned spacecrafts and spacecrafts by whether carrying the person. As an important moment, there are several characteristics between manned spacecrafts and spacecrafts in assembly process. The general assembly process is of vital importance in a spacecraft R&D system. It is at the bottom of the technical system of spacecraft manufacturing, and covers quality assurance, integrated scheduling and logistic controlling. First of all, this paper recommends the concept of the spacecraft assembly technology. And then this text introduces six aspects such as system complicated degree, the microorganism control, how to select nonmetal material, craft methods, transport methods, assembly mode to analyze the difference from spacecraft.
Force and strength analysis of FSAE racing suspension based on spatial analytic geometry
Authors: Rui Ren , Gong Bian , Fang Zhigang 
Published: October 2019

Abstract
Based on spatial analytic geometry, the paper established a mechanical of suspension system, which is aimed at the structure of double transverse arm suspension of FSAE racing car. Combined with the typical driving conditions of the car, we have worked it out with the MATLAB. Based on that, we have made the finite element static checking analysis with ANSYS, which is aimed at providing effective basis for the design and optimization of racing car.
Optimal thermal process parameters of hot stamping AA 6061
Authors: Xu Zhenhai , Liu Xiaohui , Chen Ru , Shan Debin 
Published: October 2019

Abstract
Hot stamping is a new technology developed to address the formability challenge of aluminum alloy by applying plastic deformation to the heated blank at the solution heat treatment temperature. The stamped panels gain high strength via the subsequent ageing treatment. The present paper is focused on the effect of the thermal aspects of the hot stamping process on the mechanical properties of the final formed parts. It is concluded that for AA 6061 the optimal solution heat treatment parameters are a temperature of 560 °C and a soaking time of 40 minutes, and sequent ageing should be performed at 180 °C for 6 hours. The maximum transfer time of the heated blank into the press to ensure the strong age hardening is 10 s. The low temperature could suppress the natural ageing of alloy.
Polycrystalline BiFeO3 thin films prepared by magnetic controlling sputtering method
Authors: Liu X. F. , Wang W. G. , Yin J. Q. , Wu C. S. , Chen J. X. , Wang X. J. 
Published: October 2019

Abstract
Polycrystalline BiFeO3 films were fabricated by radio frequency magnetron sputtering using a Bi1.1FeO3 target onto the glass and Si/SiO2/Ti/Pt substrates respectively. The samples which were annealed with different annealing conditions are pure without impurities. Our results indicate that there are relatively wider growth conditions for pure polycrystalline BFO phases.
Hot stamping process simulation based on reliable heat boundary condition
Authors: Huang He , Wang Qing 
Published: October 2019

Abstract
The finite element analysis is an essential precondition for the process design of hot stamping processes. The quality and the significance of the simulation results are strongly dependent on the heat boundary condition used in FE models. In this work, the heat boundary condition in hot stamping simulation was determined by analyzing the characteristics of heat transfer in the interface between the blank and the tools. The numerical simulation to the hot stamping process was made by using LS-Dyna software. It is found that the temperature changes of the hot stamped part are inhomogeneous. This results in the inhomogeneous mechanical properties.
Reliability analysis of cooling system of CNC grinding machine based on FTA analysis
Authors: Zhang Yiling , Fan Jinwei , Li Zhongsheng , Wu Changjun , Tao Haohao , Zhao Yuanyuan , Lu Qiang 
Published: October 2019

Abstract
In view of the lack of relevant research on CNC grinders in the field of reliability research of CNC machine tools at present, This research collected reliability data based on 19 MSK series grinder machine tools of a machine tool factory., found out the crucial subsystem which is the most important component to the whole, and analyzed the reliability of the subsystem adopting FTA (Fault Tree Analysis) . Statistical researched on 438 reliability data collected, combining with the actual production situation, the results shows that cooling system is the key to the reliability of the whole grinder machine tool. The 29 minimum cut sets obtained by FTA can be adjusted to improve the reliability of the cooling system, what is more, the reliability of grinder machine tool would be improved as well.
A threshold research for de-noising operation to the vibration signals based on wavelet package
Authors: Mi Wenpeng , Dong Weiwei , Li Liang , Kong Lingjian , Sun Yanglin , Chen Chao 
Published: October 2019

Abstract
Vibration signals are often interfered by salt and pepper noise, impulse noise, Gaussian noise, and other high-frequency noise, affecting the effect of vibration control research. Therefore, de-noising operation is significant for vibration signal in the practical engineering. In order to resolve this problem, wavelet package is used to remove noises from vibration signal. We provide the principle of de-noising method based on wavelet package at first. And then, the threshold selection of the method is analyzed by a vibration signal with noises. As the result shown, the noise can be effectively eliminated. This reflects that the de-noising method based on wavelet package with the hard threshold is effective.
Calibration Error Analysis of Shadowgraph Station for Large Caliber Projectile Motion Attitude Measurement
Authors: Lin Zhaodong , Gao Hongju , Sun Zhonghui , Qiao Zhiwang , Di Changan 
Published: October 2019

Abstract
The calibration principle and working process of shadowgraph station for large caliber projectile motion attitude measurement is studied. The main error factors affecting the calibration accuracy of the system are analysed, and the various errors in the calibration process are statistically analysed. The calibration error of the measurement system is calculated to be 0.062 mm. The error analysis process shows that the coincidence error between the laser optical axis and the central axis of double square nets is the main error of calibration. Among these errors, the installation error of optical window and the centering error of filtering target (Angle deviation between parallel light source beam axis and double square nets axis caused by coincidence error of reflected facula and incident facula) are the main sources of errors.
Price Forecast of Building Materials Based on GM (1,1) Model
Authors: Wu Chunfeng , Zhang Zhuai , Zhang Sheng 
Published: October 2019

Abstract
With the development of the national building materials industry, people’s energy consumption of building materials production and its own performance have also been paid more and more attention. The prediction of building material prices is a very important part of the building price management system. Based on the gray model theory, the main analysis is based on the gray prediction model to predict the price of the main building energy-saving materials required in the project, and the actual engineering case is used to verify the prediction accuracy of the gray model. The effect is hoped to provide some reference and thinking for related building energy conservation research.
Dynamic modeling and practical verification of a photovoltaic and thermal composite module system
Authors: Li Jiyong , Chen Min , Wang Jigang 
Published: October 2019

Abstract
In order to further improve the prediction accuracy of PV/T module temperature, this paper conducts dynamic modeling of PV/T module heat transfer mechanism based on lumped parameter method. The accuracy of the dynamic model was verified by experiments on typical sunny and cloudy days. The experimental results show that the maximum relative errors of the predicted values in sunny and cloudy weather are 7.8% and 7.6% respectively. The average relative errors were 4.31% and 4.37% respectively. The average absolute error is 2.04°C, 1.94°C. Compared with the existing neural network prediction methods, the mathematical model has higher prediction accuracy and shorter prediction period. This model can be used for PV/T system to formulate accurate control strategy in advance according to the temperature change situation, so as to optimize the energy saving during system operation. It can also be used for establishing the overall energy transfer model of PV/T system, realizing the coordinated control of thermal energy and electric energy and the cascade utilization of solar energy.
Application of Image Processing Technology in Building Surface Crack Detection
Authors: Xiong Xin , Huang Li , Tian Jinrong 
Published: October 2019

Abstract
The phenomenon of cracks on the surface of buildings is widespread. The existence of cracks affects the normal use of buildings, shortening the service life, seriously damaging the structure of buildings, resulting in safety accidents. Therefore, regular detection and reinforcement of cracks on the surface of buildings is a necessary link to ensure safety. At present, the detection of building surface cracks is mainly carried out by manpower with means of equipment assisted. However, there are some problems in manpower detection, such as high manpower consumption, low efficiency.This paper presents a method of detecting and inspecting cracks on building surface based on image processing technology in machine vision, which includes image gray transformation, image denoising etc. Curve fitting and least square method are used to obtain crack parameters, so as to improve the inspecting efficiency and realize the automation of building surface inspection.
Research on Optimization of Environmental Protection Scheme of Retirement Housing from the Concept of Ecological Design
Authors: Jiang Juncheng , Gao Dianbo , Chen Xianyou , He Jiajun , Lu Yuanjia 
Published: October 2019

Abstract
With the tide of aging sweeping the world, home-based care for the aged due to its unique advantages was replacing hospitals and institutions as the main and realistic choice for the elderly. For the increasing requirements of old-age care life, the concept of ecological design adhered to the characteristics of “removable, maintained, recycled and repeated”, which was rising to the basic principle of environmental protection design for residential old-age care and also an important measure to solve the problem of old-age care. This article would reflect the ecological design concept from environmental protection decoration, sound, light, water, garbage, heat and other environmental aspects to optimize the environmental protection scheme for the elderly housing, which helped enhance the “sense of acquisition” of the elderly.
Research on New Leakage Detection Technology for Converter Valve Cooling System
Authors: Yu Rongxing , Chen Chaoquan , Liu Chongqiang , Liu Keyang , Wu Jianchao , Lv Chuang 
Published: October 2019

Abstract
In order to solve the problem that the traditional leakage detection device of converter valve cannot accurately locate the leakage point, a leakage detection and location device of converter valve with two functions of leakage detection and leakage location is designed based on the leakage detection principle of sensor cable and through software programming. On this basis, an experimental platform is built, and the test results show that the short distance positioning error is within (±15 cm), which confirms the effectiveness of the device and the accuracy of positioning.
Optimization for springs of electronic brake pedal simulator
Authors: Miao Jiayu , Yao Ming , Wen Pengjing , Chai Hongjie 
Published: October 2019

Abstract
Brake pedal feedback is important for drivers to judge the braking time. Electric vehicles replace hydraulic brake pedal with electronic brake pedal simulator. Such a simulator transmits brake signal with cables. Therefore, a new electronic brake pedal simulator is designed in this paper, which can allow the implementation of an arbitrary nonlinear pedal force characteristic with electromagnet and different combinations of spring. The brake pedal feedback generated by the pedal simulator was emulated with matlab/Simulink. Furthermore, the springs were optimized to determine the combination to make the feedback meet requirements suitable for drivers. The simulated results prove the excellent brake pedal characteristic with the optimal groups of springs.
Experimental Design and Spray Technology Research of Ship Paint Spraying Robot
Authors: Xu Peng , He Jiajian , Liao Liangchuang , Gong Junjun , Zhao Shufan , Xu Kai 
Published: October 2019

Abstract
A wall climbing robot for ship painting is designed. The robot is the separation of the paint output device and the main machine of the painting equipment to realize the painting operation of the wall climbing robot. The test environment and test method design of the robot are introduced in detail, and the painting process of the robot is verified. On this basis, the thickness of paint film and the related aspects of spraying process are studied, so as to eliminate the random error caused by experience and technical techniques, and to achieve the established film thickness and the stability of paint film coating. Improve automatic spraying process and labor productivity.