bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of electromagnetic characteristics of a new electromagnetic ejection device
Authors: Ren Shi-da , Feng Gang , LI Teng-da , Yang Hui 
Published: June 2021

Abstract
Electromagnetic ejection technology is a new launching technology which uses electromagnetic force to accelerate the projectile to ultra-high sound speed. This technology can break through the speed limit of traditional gunpowder launching, and realize the accurate control of exit speed by controlling the excitation pulse current.
Four track electromagnetic launcher is a special enhanced electromagnetic launcher, which has many advantages that dual track electromagnetic launcher does not have. Its development greatly promotes the application of electromagnetic launch technology in aerospace field. In this paper, according to the practical needs of electromagnetic space launch technology, a simple four orbit electromagnetic launch device is designed and established; the finite element analysis of the model is carried out, and the electromagnetic and current characteristics are simulated, and the skin effect and proximity effect of current are obviously observed; the theoretical analysis and formula derivation of inductance gradient are carried out, and finally two kinds of inductance gradient are proposed based on the finite element theory simulation A simple example is given.
Born-Oppenheimer Molecular Dynamics of OH Radical in the SiC Grains in the Reaction-Sintered Silicon Carbide
Authors: Yang Xiaocui , Zhu Nannan , Zhao Rongxing 
Published: June 2021

Abstract
Born-oppenheimer molecular dynamics is an effective method to analyze machining mechanism of some advanced manufacturing techniques, which was introduced to investigate the absorption of OH radical on different β-SiC surfaces in the reaction-sintered silicon carbide. During the plasma oxidation-assisted polishing of reaction-sintered silicon carbide, absorption of the OH radical in the SiC grains was one of the most important process, because hardness of the SiC grains was obviously higher than that of the Si grains. the born-oppenheimer molecular dynamics model to investigate the absorption process of the OH radical was constructed firstly, which could form the foundation for the further simulation and analysis. Secondly, absorption of the OH radicals in the Si-face, those in the C-face, and those in the asymmetric face were investigated successively, which included the absorption process and the oxide product. Finally, comparisons of the absorption of the OH radical in the different faces were conducted, which aimed to further understand the plasma oxidation-assisted polishing of reaction-sintered silicon carbide. Simulation result of born-oppenheimer molecular dynamics was propitious to promote the machining level of reaction-sintered silicon carbide and promote its practical application.
Covariance transformation method for polar integrated navigation
Authors: Zhang Yongjian , Wang Lin , Wei Guo , Yu Xudong , Gao Chunfeng 
Published: June 2021

Abstract
The aircraft flying the trans-arctic routes faces the problem that the changes of navigation frames will affect the navigation accuracy. To solve this problem, taking Inertial Navigation System/Global Navigation Satellite System (INS/GNSS) integrated navigation system as an example, an integrated navigation method based on covariance transformation is proposed. This method aims at finding the transformation relationship of the system error state and the covariance between different navigation frames. The experiment and semi-physical simulation results show that the covariance transformation algorithm can effectively solve the filtering instability caused by the changes of the navigation frame. Compared with the non-covariance transformation, the system state error is reduced by an order of magnitude.
Cross-section Effect on Mechanical Properties of Al A356 Alloy Tensile Specimens
Authors: Hu Xinping , Li Ruixin , Wang Qing 
Published: June 2021

Abstract
Tensile testing is an effective method to evaluate the mechanical property of aluminum alloys. In the present work, two types of standard tensile specimens with round (RD) and rectangular (RT) cross-sections were cast in the same permanent die and their solidification characteristics, microstructures, and mechanical performances were studied. The equilibrium solidification and Scheil solidification models of the studied A350 alloy were calculated by Pandat software. The experimental solidification and cooling temperature analysis revealed that the solidification platform and supercooling of the RD sample were 3 seconds wider and 1.2 °C bigger than those of the RT one. The microstructural analysis expressed that the mean grain diameter and secondary dendrite space of RD were 1.52 and 0.75 um smaller than those of RT; hence, the strength and elongation of RD were better than those of RT. Brinell hardness tests and differential scanning calorimetry were also carried out. According to the obtained data, the round specimen was selected for tensile test because of its superior performance.
Vibration Response Testing and Evaluation of A Hydropower Station’s Gate
Authors: Peng Ding , Gaofeng Yue , Pengxiang YU , Chuansheng Yang , Shudong Gong , Lei Guan 
Published: June 2021

Abstract
We use standard vibration source to verify the method that vibration displacement was obtained by filter and integral in frequency domain. The feasibility and reliability of this method was confirmed. A gate’s vibration response such as acceleration, dynamic stress and displacement was tested. The vibration acceleration is less than 3 m/s2, the vibration displacement is less than 0.25 mm, and the dynamic stress is less than 153.2 MPa. In the initial stage of the gate lifting, the maximum vibration displacement over the standard requirements. Vibration evaluation of the gate was given by the acceleration, displacement and dynamic stress.
Research on the reform of automobile testing curriculum under the background of intelligent
Authors: Lijunling  , Xingzhihui  
Published: June 2021

Abstract
Under the background of intelligent manufacturing, the teaching and implementation of automobile testing course should keep pace with The Times. Detection course of automobiles is a particularly strong practical transportation professional course, this article mainly analyzes the automobile detection course of original defects in the teaching method, raise the significance of the integration of teaching and teaching methods, teaching means reform practice, through the reform to improve the students’ interest in learning, practice ability, flexible use of theoretical knowledge ability to solve practical problems, It is conducive to the cultivation of applied talents. It is conducive to the cultivation of intelligent manufacturing talents.
Intelligent control system for flocculation of water supply
Authors: Fan Kaiguo , Xu Yang 
Published: June 2021

Abstract
Flocculation which affects the quality of water supply is the main step of water treatment. The most commonly used control method for flocculation is the streaming current detection-based control method using a single-loop feedback. However, the traditional control system cannot adapt to the change of raw water’s quality, the set value of streaming current can only be adjusted manually. In order to solve this problem, an intelligent control system for flocculation of water supply is designed based on the neural network and fuzzy control to adjust the set value of streaming current and tune the control parameters automatically in this study. The experimental results show that the proposed intelligent control system can control the flocculant dosage accurately. It is of great significance to improve the quality of water supply and reduce the cost of water treatment.
The Enlightenment on Emergency Management of Elevator
Authors: An Ziliang , Wang Ning , Li Zhihui , Bai Dingsong , Gan Ningli , Huang Yuxin 
Published: June 2021

Abstract
Elevator is not only a means of transportation for people, but also a symbol of national science and technology. With the hot topic in the field of elevator safety, the public awareness of elevator emergency management has increased remarkably. In response to the current fragmentation dilemma of elevators in China, elevator information management system is integrated by Multi department and the operating information is pushed by APP software, so the elevator accidents would be processed effectively.
A data-driven fusion model for energy consumption prediction of hot extrusion forming
Authors: Yang Dan , Li HongCheng , Luo Rong , Liu Yitong , Cao Huajun 
Published: June 2021

Abstract
Hot extrusion forming is widely used to process lightweight parts in automobile, aircraft manufacturing, and subway industry. However, hot extrusion forming is an energy-intensive process with high environmental emissions. Because hot extrusion forming is a complex thermal-mechanical coupling process, it is difficult to develop its energy consumption prediction model based on the process mechanism. With the increasing application of data intelligent acquisition, this paper proposed a fusion data model integrating bagging enhanced ELM (Extreme Learning Machine) and GPR (Gaussian Process Regression) using their entropy weight. The energy-related data collected by energy management system are purified using the local outlier factor (LOF) algorithm and Rrelief F method. The bootstrap sampling method is used to obtain the training set and test set from the processed data. Then, the ELM and GPR are improved by the bagging algorithm for constructing the B-ELM learning model and the B-GPR learning model. Furthermore, the entropy weight method is used to further integrate the B-ELM and the B-GPR. Finally, an experiment validates the accuracy and reliability of the proposed model.
A steel classification algorithm based on surface defects
Authors: Qinge Wu , Ziming An , Lintao Zhou , Hu Chen , Yingbo Lu , Zhiyuan Ma 
Published: June 2021

Abstract
In the research of image recognition and classification, image retrieval, image data mining, and so on, feature extraction is the basic work, among which the texture feature of an image is of great significance to describe the content of the image. In this paper, an extraction method of steel texture features based on a gray co-occurrence matrix is presented, and the influence of various structural parameters on the structure is analyzed. The feature extraction of specific texture images based on a gray level co-occurrence matrix is realized, and the data classification is carried out by using a probabilistic neural network.
Based on Pearson correlation coefficient and Monte Carlo simulation method, the calculation formula of frictional resistance is optimized for soft shaft bending and pulling of steel wire
Authors: Wang Tengfei , Li Jian , Liu Yisheng 
Published: June 2021

Abstract
The main content of this study is based on Pearson correlation coefficient and Monte Carlo simulation method to optimize the frictional resistance calculation formula for pushing and pulling flexible wire shafts in different bending states. According to the calculation formula and experimental data of the frictional resistance of the soft shaft bending of the wire, in order to improve the calculation accuracy, the Pearson correlation coefficient test is carried out by f f=μDβPyn
/1 + y2
SPSS software, and the coefficient β and the corresponding friction f between the shaft core and the sheath are very relevant at all angles, so the size of the β can be adjusted to make the calculation of friction f more accurate. The parameters and parameters of the formula β modified by the Monte Carlo simulation method, and the frictional resistance formula of the flexible wire rope shaft at different angles is optimized. The optimized formula is calculated with an overall error of 2.3260%, which is 1.5637% lower than the original total error of 3.8898%, and is suitable for soft shaft friction with different diameters at a certain calculation angle.
Research on Geometric Error Prediction of High Speed Dry Cutting Gear Hobbing Based on MPGA and BPNN
Authors: Hou Yuehui , Yan Chunping , Chen Jianlin , Chen Liang 
Published: June 2021

Abstract
The geometric error of high-speed dry cutting gear hobbing is affected by many factors, such as process parameters, gear hobbing machine tools and hobs, and it is difficult to predict. This paper uses the vibration of the hob spindle to predict the geometric error, and builds a geometric error prediction model for high-speed dry cutting gear hobbing based on multiple population genetic algorithms and BP neural network. This model comprehensively considers the influence of the hob spindle speed, feed rate and hob spindle vibration on the geometric errors of high-speed dry cutting gear hobbing, which can provide a useful reference for the improvement of gear machining geometric accuracy. Through the experiment, it is concluded that adding the hob spindle vibration during the machining process as the model input can obtain more accurate prediction results of the geometric error of the hobbing machining. Compared with the traditional BP neural network prediction model, this model has better prediction ability.
Research on Multiple Signal Synthesis Methods in Space Electromagnetic Environment Simulation
Authors: Yuan Wang , Wei Tan , Lidong Cui , Ying Li 
Published: June 2021

Abstract
This paper proposes three spatial electromagnetic signal environment concepts from three levels: general electromagnetic signal environment, relative electromagnetic signal environment and electronic warfare signal environment. It can solve the difficult problem of comprehensive, accurate and targeted description of the electromagnetic environment in the space electromagnetic environment simulation of the spacecraft. This paper studies the synthesis method of various types of signals contained in the three electromagnetic signal environments in a certain area, and provides a reference for the accurate simulation of the dynamic and intuitive, hierarchical electromagnetic environment situation in a certain area of space.
Research on the Updating Method of Vehicle Frame Finite Element Model
Authors: Lu Zhen , Yang Zengjie , Yang Zhongliang 
Published: June 2021

Abstract
First, the strain gauges were pasted on the front and back tie rods of the vehicle for the sake of calibration. Under the designated working conditions, the strain data of the tie rods were collected via a data acquisition unit (DEWESoft). Meanwhile, the pressure of suspension cylinder was measured, the force distribution ratio of front axle and back axle was respectively calculated through the strain data and cylinder pressure data, and the calculation formula of the distribution ratio was obtained. The calculation results were verified through a traction test of the complete vehicle. In the end, the finite element model was updated according to the test data, followed by the analysis of the structural stiffness and strength. The method proposed in this paper will considerably contribute to the improvement of finite element analysis accuracy of the complete vehicle, and moreover, it can be promoted in the design of other similar structures, with a certain reference significance.
The influence of gravity load on the accuracy of mesh reflector antenna
Authors: Wang Lipeng , Zhang Xin , Hu Jianfeng , Yang Zhao , Xiao Yong 
Published: June 2021

Abstract
Space large deployable mesh antennas are the focus of research in the aerospace field. There is a high requirement for the reflector surface accuracy of the mesh antenna in orbit. Due to the low stiffness of the truss cable net system, the deformation of the flexible mesh surface under the ground gravity load cannot be ignored. Therefore, it is the key technology to ensure the accuracy of on orbit cable network reflector that accurately predict the difference of reflector under gravity load and microgravity load. This study establishes the mechanical model of the cable-truss system. The Newton Iterative Method is used to solve the nodal nonlinear equilibrium equation in the gravity load, and the deformation of the antenna mesh surface under the gravity load is obtained.
Development of a ceramic double thick GEM detector for transmission measurements at the VESUVIO instrument at ISIS
Authors: Cancelli S. , Muraro A. , Perelli Cippo E. , Romanelli G. , Abba A. , Chen Y. , Grosso G. , Gorini G. , Hu Z. , Lai C.-C. , Mc Cormack O. , Robinson L. , Svensson P.-O. , Tardocchi M. , Hall-Wilton R. , Xie Y. , Zhijia S. , Zhou J. , Zhou X. , Croci G. 
Published: June 2021

Abstract
Neutron spallation sources always require new instrument upgrades and innovations in order to improve the quality of their experiments. In this framework, the capability to accurately measure total neutron cross sections at the VESUVIO instrument at the ISIS Facility can be boosted by a tailored transmission detector. For this reason, the first double ceramic thick GEM detector has been realised.
Detectors based on GEM technology are broadly developed thanks to their characteristics, such as good spatial resolution (< 0.5 mm), good detection efficiency, high rate capability (MHz/mm2) and a possible coverage area of some meters at low costs. This article shows the realisation of a GEM detector made of a 10B4C cathode, two ceramic thick GEM foils and a padded anode, as well as the device characterisation on the VESUVIO beam line, where stability, γ-sensitivity, imaging capability and sample analysis have been studied.
The successful results confirm that the ceramic thick GEM detector performs well in thermal and epithermal neutron detection and it will allow the scientific user community of the instrument to perform better quality transmission measurements so as to determine more accurate total neutron cross section of condensed-matter systems.
Prototype of simultaneous bidirectional data-transmitter in 65 nm CMOS
Authors: Kishishita T. , Krüger H. 
Published: June 2021

Abstract
This article presents a design and implementation of an I/O
circuit block capable of simultaneous bidirectional
data-transmission in CMOS integrated circuits. Merging
data-transmitter and receiver into common bonding pad is feasible
not only to reduce the number of transmission lines from a
considerable number of chips, but also to realize more
area-efficient data handling in consequence of flexible inter-chip
communication. This feature is attractive from the viewpoint of
detector systems in high energy experiments, in which reducing
materials such as cables from silicon trackers in inner vertex
layers is of major importance to suppress multiple-scattering and to
achieve good overall detector performances. The circuit block
presented here is designed on the basis of a current subtraction
circuit and two distinct current-mode logic drivers. Its principle
is also applicable to widely-used low-voltage differential signal
drivers and easy for process migration. The prototype chip was
fabricated in a 65 nm CMOS technology. Working principle has been
demonstrated in preliminary laboratory testing.
Calculation of a food consumption nitrogen footprint for Germany
Authors: Klement Laura , Bach Martin , Geupel Markus , Breuer Lutz 
Published: June 2021

Abstract
Reactive nitrogen (Nr) that is released to the environment has several negative implications for the atmosphere, hydrosphere, biodiversity and human health. A nitrogen (N) footprint is a measure that can help to assess and communicate the impact of personal lifestyle and consumption choices regarding their influences on Nr losses. The N-Calculator tool was developed to estimate this footprint. However, underlying loss factors for the food sector in the N-Calculator rely on data from the US, for which the calculator was originally established. Since the conditions in agriculture and the food industry differ significantly between the US and other countries, and the fact that the food sector is considered the main source of Nr losses in the N-Calculator, a revision of the N-Calculator is required if applied to other countries. Here we present a revised N-Calculator for Germany that is based on German food production data. In this study, virtual nitrogen factors describe the losses of nitrogen in a supply chain. Losses were calculated for 20 plant-based products, 17 feed materials, 18 compound feeds and 14 animal-based products. The N footprint varies considerably between products. While plant-based products amount to a weighted average of 3.4 g N loss per kg product, animal-based products cause significantly higher losses with 40.5 g N loss per kg. Overall, the average N footprint for the German consumer is calculated to be at 9.94 kg per capita and year. To validate the results, the individual categories were scaled up to the national level and then compared with statistical data on N flows in Germany. In general, the results showed good agreement with key production figures and the overall N budget for Germany. Furthermore, some improvements are proposed to increase the informative value and user acceptance of an N-Calculator.
Research on Large Deformation Mechanism and Countermeasures of Shallow Buried Soft Rock Tunnel with Abundant Water
Authors: Yuan Qing , Chen Shihao , Xiao Jing , Xiong Qihuan , Zhang Ziping 
Published: June 2021

Abstract
In view of the obvious deformation characteristics of shallow buried soft surrounding rock tunnels affected by excavation disturbance, this article takes a Tunnel as the engineering background and combines the geological conditions of the tunnel to carry out on-site monitoring and analysis of surrounding rock deformation after tunnel excavation. The deformation after excavation has the characteristics of fast deformation speed, long duration and large deformation. In addition, the excavation position and step have an important influence on the settlement of the vault and the convergence of the surrounding rock. The settlement of the vault and the convergence of the surrounding rock caused by the excavation of the upper and middle steps account for 61.16% and 63.34% of the total deformation respectively. Through the analysis of large deformation and collapse phenomenon, it is known that the large deformation mechanism in the cave mainly includes soft rock plastic flow and progressive loosening expansion. The soft rock plastic flow caused phenomena such as side wall bulging, top pressure and steel arch distortion, and the progressive loosening and expansion caused the collapse of the tunnel face and surface cracks. Finally, according to the principles of the New Austrian Method, temporary support (transverse bracing + vertical bracing) + grouting anchor pipe + spray-mixing coordinated support was used to construct the pipe shed at the same time, and the support was optimized, the leading small conduit was encrypted, and added Measures such as temporary invert and lock-foot anchor pipe have successfully dealt with the large deformation section of the collapse, and the treatment effect is good, which can provide reference and reference for similar projects.
Temperature stress analysis of the overlong concrete structure in the basement of the Shangshenbei block project in Hunnan New City
Authors: Zhao Ran , Wang Kai Wei 
Published: June 2021

Abstract
This paper is based on a typical project in Shenyang Shangshenbei Block Project, using Midas software to analyze the temperature stress of the basement concrete structure and the temperature stress changes of various parts of the basement, combining the conditions and characteristics of the concrete structure cracks, and putting forward optimization suggestions and effective resistance. Cracking measures, through the implementation of measures, effectively reduced the occurrence of cracks and ensured the stability of the structure.