bluuebunny/crossref_metadata_2025_split huggingface dataset:
An overview of impact resistance of auxetic lattice structure
Authors: Huang Xiufeng , Zhang Zhenhua , Wu Jihang 
Published: June 2020

Abstract
Auxetic materials have many advantages in strength and energy absorption, which have become a research focus of scholars at home and abroad. It’s of great significance to ship protection structure design that researching deeply on auxetic lattice structures. According to the unique properties of auxetic lattice structures, this paper mainly introduces the research status of the impact resistance mechanical properties of the new structure. The research status of low-speed impact, high-speed projectile impact, and explosion impact in the auxetic lattice structures is described from three aspects: theoretical, experimental and simulation studies. The research status of in-plane impact at medium and low velocities, explosive impact and projectile penetration is expounded. The effects of geometric parameters and impact velocity on deformation modes and energy absorption of structures are also analyzed. Finally, summarize the article and point out the contents in the future.
Application of Visual Simulation Technology Based on the Virtools Method in Equipment Virtual Maintenance
Authors: Wang Xin , Wang Yibo , Meng Xianggang 
Published: June 2020

Abstract
In this paper, 3dsmax is used to build three-dimensional model of scene and virtual equipment. Virtools is used to edit various maintenance scenes and build a virtual maintenance system consistent with the actual environment. According to the operator’s action instructions, the system shows the real-time human-computer interaction process, the state change of the model, the scene response process after the operation, which makes the virtual environment and the real installation operation consistent, and realizes the virtual maintenance training of the equipment. The virtual maintenance training system can be applied to the maintenance training in Colleges and universities, so as to reduce the loss of real equipment and improve the efficiency of equipment use.
Anti-school Bullying System Based on Voiceprint Recognition
Authors: Yu Hao 
Published: June 2020

Abstract
The article is devoted to the study of an Anti-school Bullying system based on Voiceprint Recognition. Through the introduction of the social background of the phenomenon of bullying and the existing relevant technological background, the design of an Anti-school Bullying system based on Voiceprint Recognition technology is introduced, and the analysis of the system is made.
Analysis of Damage and Crack Propagation in Unidirectional Composite Laminates with a Peridynamic Model
Authors: Shen Rulin , Xiong Rui , Gong Yanling 
Published: June 2020

Abstract
A continuous function was applied to establish a peridynamics model to study the damage of unidirectional composite laminate, a kind of transverse isotropic material with three-dimensional (3D) structure. To express the interaction of nonadjacent layers and the influence of thickness on elastic deformation and damage, this paper employed a spherical material horizon. The spherical harmonics function was applied to express the relationship of the micro-elastic modulus and the bond-fiber angle, as well as critical bond stretch and the bond-fiber angle, respectively. Spatial stress or strain conditions were employed to calculate the strain energy density and solve the bond stiffness constant. The model was verified with unidirectional multilayer composite laminate with orifice. The damage mode and the crack propagation process of laminates with orifice were also consistent with that of experimental.
Study on Surface Flashover Characteristics in SF6/CF4 Mixture
Authors: Zhai Zhixuan , Hua Yue , Xue Yuchen , Yang Songhan , Zhang Lei , Li Bo , Lin Yuan , Su Yang , Hao Wenfeng , Hu Yang , Wang Qinghao 
Published: June 2020

Abstract
Surface flashover characteristic of epoxy resin composite material in SF6/CF4 mix gas were studied through experimental method, and the influence of several key parameters were analyzed, such as gas pressure, SF6 mix ratio and voltage polarity. It is shown that, when the mix ratio of SF6 in the mixed gas is 40%, the flashover voltage of epoxy resin insulator can reach over 60% of the flashover voltage in SF6 with the same pressure. The synergistic effects in the needle-plate electrodes system have significant difference between positive and negative polarity. The synergistic effect for negative polarity is weaker than that in negative polarity. Comprehensive environmental requirements and surface flashover characteristics, the results provide a potential SF6 alternative for GIS equipment.
Simulation of Hot Stamping Process Based on Deform Software
Authors: Huang He , Lu Yuansan 
Published: June 2020

AbstractTaking the U-shaped part of 22MnB5 ultra-high-strength steel as an example, a finite element model of hot stamping was established. The DEFORMV11.0 software was used to simulate the deformation process and the temperature field distribution of the sheet during hot forming. The results show that the temperature of the sheet varies with the different locations in the hot stamping process. The side wall of the sheet cools faster. Meanwhile, the temperature changes in the different positions of the concave mold and the convex mold are not uniform. The temperature change of the punch with the largest contact with the sheet is more obvious.
Research on the Application and Development Trend of Automation in Mechanical Manufacturing
Authors: Yin Jiankai , Yang Jianan , Huang Jingru 
Published: June 2020

Abstract
With the development of science and technology, automation is increasingly used in industrial production, which has greatly improved production efficiency. Based on this, this article studies the application and development trend of automation in mechanical manufacturing. First of all, automation was summarized, its concept, basic characteristics and development status were introduced, and then the application of automation technology in machinery manufacturing was analyzed, including application principles and practical applications. Next, we explained the development trend of automation in the field of machinery manufacturing, and then several problems in the current development were explained, and finally we put forward corresponding suggestions based on the above analysis. The application of automation technology has great advantages in cost control and improving the core competitiveness of the market. To ensure its long-term development, we must attach importance to the introduction of new technologies and the optimization of production quality.
Preparation and Characterization of a New Composite Adsorption Materials Composed of Two Activated Alumina and Microporous Molecular Sieve and Its Adsorption Property to Water
Authors: Zhang Haoyue , Wang Yongquan , Zhang Zhongbin , Niu Baolian 
Published: June 2020

Abstract
In order to improve the comprehensive performance of solid adsorption desiccant for compressed air adsorption dryer and reduce the loss rate of adsorption dryer, a new type of binary composite solid adsorption material suitable for compressed air drying is put forward. This material is composed of activated alumina (matrix) and 4A molecular sieve and 13X molecular sieve respectively in the proportions of 95%/5%, 90%/10% and 85%/15%. Static characteristic analysis is first made on three macro characteristic parameters, including the compressive strength, specific surface area and static water adsorption (60%RH). Thereafter, microscopic surface morphology analysis on composite material samples are employed. Comparative analysis result shows that, for compressed air drying, the activated alumina/13x molecular sieve with the proportion of 85%/15% is better than the 90%/10% activated alumina/4A molecular sieve composite solid adsorption material.
Lightweight Drill Pipe Based on Composite Carbon Fiber Material
Authors: Jiang Keyue , Xie Ruiheng , Yun Hanfang 
Published: June 2020

Abstract
At present, our country’s drilling platforms mainly use alloy high-speed shafts. Due to the long transmission torque of drill pipes, drill collars and so on, the drill pipes are subjected to excessive torque and torque during operation, which often lead to fracture failure. The working environment of the drill pipe is wet underground, which is easy to corrode due to chemical reaction with the surrounding environment, thus causing the strength of the high-speed shaft to reduce and corrode, accelerating the fracture of the drill pipe, causing a large amount of waste of engineering materials and causing more serious environmental pollution problems. Based on the defects of the metal main shaft mentioned above, carbon fiber material is used as the main material of the high-speed shaft to avoid the corrosion of the main shaft caused by the changeable environment during drilling operation. Meanwhile, it has higher compressive strength, torsional strength and high temperature resistance. The invention can reduce the cost of transportation and installation parts, consume less electric energy during operation, reduce the weight of the drilling platform itself, and reduce a large amount of unnecessary cost in the drilling industry.
Effect of Spinning Process Parameters on the Forming Quality of Inner and Outer Teeth Shaped Parts
Authors: Wu Minhui , Xu Xiao , Xia Qinxiang , Cheng Xiuquan 
Published: June 2020

Abstract
Deform-3d software was used to conduct numerical simulation on the spinning forming process of inner and outer teeth to study the strain distribution and material flow law during the spinning forming process. The influence of mandrel rotation speed and roller feed speed on the forming quality of inner and outer teeth profile was studied. The results show that the best forming quality of the spinning parts can be obtained under the combination of the process parameters of the mandrel rotation speed of 150r/min and the roller feed speed of 110mm/min. Compared with the experimental results, the maximum relative errors of inner and outer teeth wall thickness were 2.03% and 1.78%, which verified the reliability of the finite element model. The results can provide guidance for the finite element simulation and production of inner and outer teeth spinning forming process.
Study on the support performance of portal support under different confining pressure
Authors: Song Jiaqi , Dong An 
Published: June 2020

Abstract
In this paper, a certain section and hydraulic support of Hongyang No.3 coal mine are taken as the research object. The numerical model of coupling between the tunnel and hydraulic support is established by using the finite element software ABAQUS. The Mises stress of the tunnel and support under different confining pressure is analyzed. The results show that: Under different confining pressure, the maximum Mises stress appears at the arch foot of the tunnel, with the increase of confining pressure, the Mises stress at the arch foot is rising, and the increase of Mises stress at the left arch foot is greater than that at the right arch foot. The uneven stress of the tunnel increases, and the tunnel is more prone to damage. With the increase of the confining pressure, the Mises stress of the middle pillar of the portal support decreases continuously. The load is mainly borne by the columns on both sides. The middle pillar cannot play its bearing capacity, which is not conducive to the support of the tunnel.
Measurement of oxide layer thickness on 7050 aluminum alloy surface based on image processing technology
Authors: Zhang Maolin , Cai Song , Huo Yongqing , Chen Zhiren , Wu Zhilin 
Published: June 2020

Abstract
This paper presents a method for measuring the thickness of the oxide layer on the surface of 7050 aluminum alloy based on image processing technology. As the 7050 aluminum alloy is oxidized to different degrees at different temperatures and different holding times, its surface color will also change significantly with the degree of oxidation. The image processing method was used to obtain the gray value of the sample photos with different degrees of oxidation, and the surface oxide layer of the sample was subjected to Ar+ layer-by-layer sputter peeling. XPS analysis was performed on the peeled surface to calculate the thickness of the oxide layer. The oxidation was found. Relationship between layer thickness and gray value. The thickness of the oxide layer can be obtained by extracting the gray value of the surface of the test object. This measurement method has the advantages of low cost, non-contact, reliable measurement, convenient and fast.
Process parameters optimization of single-track laser cladding for 45 steel gear remanufacturing
Authors: Yu Tianbiao , Shi Bowen , Song Boxue 
Published: June 2020

Abstract
In order to research the optimal combination of process parameters for the remanufacturing of 45 steel gear with RCF104 alloy powder, three-factor and five-level orthogonal experiments of laser power, scanning speed and powder feeding speed were carried out on 45 steel substrate. The best process parameters combination was selected by considering the shape coefficient of the cladding layer, dilution rate, cladding width and cladding height. The microstructure of the cladding layer was analyzed, the horizontal and vertical microhardness of the cladding layer was measured. The results show that the optimal combination of process parameters was laser power 448 w, scanning speed 6 mm/s, powder feeding speed 9.0369 g/min. The analysis of variance shows that the laser power and scanning speed were the main factors influencing the cladding width and the scanning speed had a significant influence on the cladding height and shape coefficient. The microstructure analysis of cladding layer shows that planar crystals, cellular crystals, columnar crystals, dendrites and equiaxed crystals changed gradually from bottom to top. The average microhardness of the cladding layer was 672.2HV, which was 3.08 times of the matrix hardness.
Collaborative Filtering Recommendation Algorithm Based on User Preferences
Authors: Yan Yongjie , Xie Hui 
Published: June 2020

Abstract
The personalized recommendation technology provide people an effective method to solve the problem of information overload. Collaborative filtering is one of the key algorithm of recommendation technology, In this paper, the User-Movie (UM) model based on multilayer perceptron algorithm is a kind of item-based collaborative filtering recommendation algorithm. Therefore, the paper puts forward a new method to integrate item similarity in the UM model. Using Jaccard to find the similar items of current item, respectively. Experiments on the well-known datasets Epinions and Movielens show that the algorithm weighted by Jaccard in the case of sparse datasets and less neighbor achieves great improvement of prediction accuracy.
Comparison of accuracy and precision of various types of photo-curing printing technology
Authors: Yao Lu , Hu Peixin , Wu Zhangping , Liu Wu , Lv Qitao , Nie Zilin , Zhengdi He 
Published: June 2020

Abstract
Light-cured 3D printing technology has always had a series of advantages such as high precision, fast forming speed and low cost compared with other printing technologies. Since the invention of Stereo lithography Appearance(SLA) printing technology in 1986, light-cured 3D printing has been developing rapidly, and has been derived into Digital Light Processing (DLP), Laser cladding deposition (LCD), Continuous Liquid Interface Production (CLIP), etc. Object: The roughness of the printed products of various photocurable printers was evaluated by the surface morphology of the printed products on the micro level, Compared with the original digital file model, the dimensional accuracy of printed products of various types of photo-curing printers is evaluated. Materials and Methods: A digital 3D model was obtained by scanning the adult maxillary teeth with a 3shape mouth scanner. Save the upper digital three-dimensional model as an STL file and print it as a physical model using three different 3D printers(UNIZ (LCD), Han’s laser SLA 6000 (SLA) and Han’s laser DLP (DLP)). Again, use 3shape to scan the physical model into a 3D digital model and use the Dental Cad to compare the accuracy. Test blocks (20mm*10mm*5mm) were printed using three different printers, and the surface topography was observed using a KEYENCE optical microscope, and data comparison was performed using DANTAL CAD for file fitting. Results and Conclusion: On the Z direction, the surface bump SLA was 185.1 micron mum, the LCD 105.4 mum, and the DLP 95.2 mum. SLA<LCD<DLP. The model fit DLP was 0.07 mm, the LCD was 0.10 mm, and the SLA was 0.14 mm. In terms of print accuracy, DLP > LCD > SLA. The surface roughness of the test block was DLP>SLA>LCD. Conclusion: DLP performs well in all aspects.
Research Progress in Modeling Methods of Rat Lung Fibrosis
Authors: Zhao Xin , Cao Zhengmin , Wang Ruipeng , Liu Shuang 
Published: June 2020

Abstract
Pulmonary fibrosis affects human respiratory function, and severe cases can lead to progressive loss of lung function. Early intervention and early treatment are important for the prognosis of lung fiber. The establishment of pulmonary fibrosis model is of great significance to study the pathogenesis and pathological process of pulmonary fibrosis. Rats are usually selected to model pulmonary fibrosis in various ways. By retrospectively summing up the rat PF model, progress has been made in the study of pulmonary fibrosis.
Optimization of Al-doped ZnO films by RF magnetron sputtering at room temperature for Cu (In, Ga) Se2 solar cells
Authors: Zhang Xianyang , Zhu Rongyang 
Published: June 2020

Abstract
In this work, Al-doped zinc oxide (AZO) thin films were deposited by RF magnetron sputtering with various RF power at room temperature. The effect of RF power on the structural, electrical, and optical properties of AZO thin films were investigated by XRD, SEM, UV–Vis–NIR spectroscopy and Hall measurements. The lowest resistivity of 1.8×10−3 Ω·cm was obtained at the highest RF power of 450 W. The average optical transmittance is about 90% in the visible range and above 80% in the range of 300-2000 nm. CIGS thin-film solar cells were prepared using the AZO films as the windows layer and an efficiency of 15.36% in CIGS solar cell has been achieved.
How does informed trader trade the “reverse risk”? --OTM Option volume as risk factor for stock prediction
Authors: Guo Jing , Xiao Jie , Ni Zhongxin 
Published: June 2020

Abstract
This article researches the implied risks in the trading volume data of the SSE (Shanghai Security Exchange) 50 ETF options, and explores the power of these risks to predict the return of the underlying stocks. By analyzing the trading behavior of informed option traders, we believe that the trading volume of the OTM (out-of-money) options can capture these traders’ expectations of the “reverse risk”. We divide “reverse risk” into two types of risk information: the first one is the option selection process: the trader decides whether to choose a OTM option or a non-OTM option to hedge their private information, which represents whether they expect the future stock to reverse; the second risk information is measured by the change amount of the current OTM option trading volume, which depicts the new information shock brought by these informed traders’ behavior. The empirical result shows that the option selection process can significantly predict the future returns of the SSE 50 index, while the information shock caused by the change in OTM options trading volume has solid pricing power among individual stocks. We then use Granger causality test to explore the mechanism of risk transmission for the “reverse risk” trading process, and conclude as: the risk information held by informed traders(those who believe the future market will “reverse”) first affected their decision-making process, and their decisions in the options market will transmit the risk to the SSE 50 index trading market, and then cause the current information shocks, and these shocks will eventually affect the constituent stocks of the SSE 50.
A new numerical production well model for the low-permeability gas reservoir
Authors: Yao Yumin , Shi Anfeng , Wang Xiaohong , Wang Min 
Published: June 2020

Abstract
In the development of low permeability gas reservoirs, capillary end effect has a significant impact on the flow near the production well, and physical quantities near the production well all change dramatically, which may reduce the oil and gas production. Traditional well model cannot describe this phenomenon. In this paper, based upon the analytical solution of one dimensional radial flow, an alternative numerical well model for low permeability gas reservoir considering the end effect is constructed. The numerical results show that the gas and water productions can be predicted accurately at different grid scales using the proposed well model. In contrast, the Peaceman well model for multi-phase only can get the accurate results when the grid is enough subdivided.
Study on the Characteristics and Influence Factors of Spontaneous Imbibition in the Fractured Reservoirs
Authors: Li Lu , Wang Min , Wang Xiaohong 
Published: June 2020

Abstract
Spontaneous imbibition is an important mechanism for oil recovery in the natural fractured reservoirs. It’s crucial to study the characteristics and influence factors of the imbibition process. We present analytical solutions for the one-dimensional incompressible imbibition process. Based on analytical solution, we study the effect of some factors on the imbibition process. It is also found in this paper that the larger the viscosity ratio is, the smaller the critical saturation is. A new scaling group is also suggested in this paper to fit experiment data.
Safety analysis of gas pipeline under vehicle load
Authors: Su Chang , Zhu Baikang , Zhu Bin , Yang Xu 
Published: June 2020

Abstract
With the rapid development of the economy, construction has been carried out throughout the country. Natural gas pipe network is widely distributed, so construction vehicles driving on the ground with buried gas pipelines often exert pressure on the pipelines. If the pipelines are not buried deep enough, the pipeline material strength is poor or the construction quality is not qualified, the pipelines may be deformed or even broken when they are under high pressure. In this paper, the influence of excavator and heavy truck load on gas pipeline is analyzed by using finite element software. The results show that the construction vehicle propagates pressure load through the soil, which causes the local concentrated pressure above the pipeline and causes the pipeline deformation. In view of the safety hidden danger caused by the third party construction vehicles, this paper also gives some Suggestions and measures.
Research on Volcanic Reservoir Prediction in Jinlong-2 Well Area
Authors: Kong Chuixian , Xiao Yang , Chen Lichang , Jia Junfei , Zhang Huiyong 
Published: June 2020

Abstract
Volcanic reservoirs have complex distribution that reservoir prediction is often required to provide a basis for development target optimization and horizontal well trajectory optimization. By analyzing the development model and petrographic distribution of volcanic reservoirs in Jinlong-2 well area of Junggar Basin, the lithology, porosity and oil saturation of volcanic rocks are predicted further. Defining favorable reservoir areas provides a basis for development target optimization and horizontal well trajectory optimization.