bluuebunny/crossref_metadata_2025 huggingface dataset:
Deformation mechanism of neutron irradiated Al-B based on SEM-DIC
Authors: Xiang Jiaqi , Feng Qijie , Cheng Junchao , Lu Lei , Huang Junyu , Zhong Zhengye
Published: January 2022

The electron backscatter diffraction (EBSD) characterization of irradiated Al-B shows that there is a high concentration defect region around the borides. Nanoscale speckle particles were successfully prepared on the surface of Al-B before and after irradiation, and then the mesoscale strain during in-situ deformation was obtained by digital image correlation (DIC) technique. The results shows that slip band bypass such an area through cross slips with slip band deflection. Transmission electron microscopy (TEM) indicates that abundant helium bubbles exist in the deflected slip band area pinning the dislocations.
Dynamic corrosion mechanical properties of magnesium alloys with Erbium in the chloride ions environment
Authors: Yang Miao , Xing Liyun , Liu Xiaobo , Dong Yuqi , Jin Jiliang
Published: January 2022

The X-ray diffraction (XRD), scanning electron microscope (SEM), weight loss corrosion rate, corrosion residual strength (CRS), and slow strain rate tensile (SSRT) methods were used to study the effects of the addition of rare earth Erbium (Er) on the dynamic corrosion mechanical properties of the AM50 magnesium alloy. The results show that after Er was added, a new phase of Al3Er appeared and the microstructure was refined. The corrosion resistance of rare earth Er addition to the alloy was 0.5% > 1.5% > 1.0% > 0. Furthermore, the corrosion rates decreased in 432 h. The CRS results within 168 h show that the strength after an addition of 0.5% Er was the highest and the decline rate was the smallest. According to the shape of the tensile curve of CRS and the morphology of the tensile fracture, the addition of rare earth Er did not change the fracture form of the alloy, which remained as quasi-cleavage.
Research on the law of reflection coefficient of reflective film of traffic sign based on Angle
Authors: Meng Yu , Sun Mengru , Li Dan , Shi Yufeng , Cheng Cheng , Qi Muyu , Yang Ye
Published: January 2022

In this paper, a large number of digital printing reflective film retroreflectivity measurement. Based on the multi-angle test of the reflective film of the mainstream manufacturers in the market, the reverse reflection coefficient of the digital printing reflective film was obtained. Through the curve fitting of the measured values of the backreflection coefficient under different measuring angles by using the scatter plot, the variation law of the luminosity of the digital printing reflective film with incident Angle and observation Angle was obtained. The variation law of backreflection coefficient explored in this paper has certain significance to the application guidance of digital printing reflective film for traffic signs.
First principles calculation of electronic properties and effective mass of zinc-blende GaN
Authors: Xie Guangqi , Wang Huanyou
Published: January 2022

Based on the first principle pseudopotential plane wave method, the electronic structure of zinc-blende semiconductor GaN is calculated. Using the relativistic treatment of valence states, the spin orbit splitting energy of valence band top near the center of Brillouin region is calculated. Based on the effective mass approximation theory, the effective mass of electrons near the bottom of the conduction band and the effective mass of light and heavy holes near the Γ point along the directions of [100], [110] and [111] are calculated. These parameters are valuable and important parameters of optoelectronic materials.
A new method for testing wide range horizontal field angle
Authors: Huang Sijie , Huang Jin , Wang Shujie , Ma Zhenwei , Gu Shangyu
Published: January 2022

In order to solve the problems of small measurement range, large error and low efficiency of laboratory optical field angle testing, a high-precision, easy -operating, high-efficient, and widely used horizontal field angle test method is proposed. It comes to a conclusion that the test method can reduce the experimental error through the analysis of the principle of the field of view error and the calculation of laboratory simulation. The simulation results show that for cameras with a field of view of more than 150 degrees, the measurement error can be reduced by 37 degrees, and when the field of view of the camera under test is close to 170 degrees, the method can reduce the measurement error by nearly 54 degrees. Meanwhile, a wide-range horizontal field angle measurement method is proposed. The camera under test is moved on the supporting mobile platform to image the target test board, and then the imaging target is read by reading the scale value on the test board calculates the angle of the camera under test. This method can effectively avoid the measurement error of the angle caused by the distance between the center of the lens surface and the center of the entrance pupil, so as to quickly obtain the angle of view test results, and improve the testing accuracy, and it is also suitable for cameras that measure a wide range of field angles (wide-angle camera or fisheye camera, etc.) to solve the problem of laboratory testing a wide range of horizontal field angles.
Influence of roundness error screw on running characteristics of sliding bearing based on SDT
Authors: Chen Zhenyu , Xu Wubin , Li Bing
Published: January 2022

In order to study the influence of roundness error on the oil film characteristics of journal bearing rotor system, a dynamic model of journal bearing rotor system with roundness error was established, and a new generalized roundness error equation is derived based on the small displacement screw (SDT) theory. And the influence of roundness error screw parameter dx represented by SDT on critical speed and stability of sliding bearing is analyzed emphatically. The results show that the existence of journal roundness error is beneficial to the bearing capacity and stability of sliding bearing rotor system to a certain extent, and with the increase of roundness error screw parameter, its promoting effect is more obvious; At the same time, the critical speed of the system will increase with the increase of screw parameter, especially when eccentricity ε>0.6; And when Sommerfeld number S>0.6, the roundness error of journal has little influence on stability.
Nonlinear modeling and transition corridor calculation of a tiltrotor without cyclic pitch
Authors: Fan Yourong , Wang Xinhua , Hu Zhe , Zhang Kai
Published: January 2022

In order to solve the problem of rotor airflow interference to the wing of tiltrotor UAV, the lift and drag in the slipstream area and the free flow area were calculated respectively according to the hydrodynamics theory and CFD simulation. The longitudinal nonlinear dynamics model of tiltrotor UAV is established by Newton-Euler method. In order to solve the problem that the lift and thrust are difficult to balance the body gravity in the transition flight mode, a method for calculating the transition corridor of a tiltrotor UAV without cyclic pitch is proposed. The boundary of the transition corridor is restricted by the Angle of attack of the wing and the thrust of the rotor. Considering the requirements of UAV cruise speed, flight safety and minimum energy consumption, the optimal transition curve is selected. The result show that the designed transition curve can ensure that the lift and the rotor thrust can balance the gravity completely and the Angle of attack is in a reasonable range, and the rotor force has enough margin of safety.
Study on denitration performance of multi element modified MIL-101 (Fe) at low temperature
Authors: Wang Shuqin , Li Xiaoxue , Wu Jinjin
Published: January 2022

MIL-101 (Fe) was modified by amino group and doped by Cu and Co elements by microwave hydrothermal method. The effect of SCR denitrification at low temperature was investigated with high concentration of NOx as adsorption object. The results show that when the flue gas temperature is 200 °C and the NOx concentration is up to 1640 mg/m3, the removal efficiency of NOx can reach 86% under the optimal conditions, which is 1.5 times higher than that before modification. In addition, the characterization results indicated that the specific surface area of the modified catalyst increased, the thermal stability was good at low temperature, the selective adsorption capacity of NO was enhanced, and the doping played a synergistic catalytic role. It can be used for flue gas denitration in various industries.
Microwave dielectric properties of Na+-substituted CaMg0.9Li0.2Si2O6 ceramics
Authors: Huang Fangyi , Su Hua , Tang Xiaoli
Published: January 2022

Ceramics with low dielectric constant are widely used in high frequency substrates. The low temperature sintered CaMg0.9-xNa2xLi0.2Si2O6(x = 0–0.05 and 0.1) ceramics with low dielectric constant and dielectric loss were prepared by the traditional solid-state reaction method, with 0.5wt%LBSCA additive. The XRD patterns of the samples were obtained by X-ray diffraction and it was found that there were three ceramic components, CaMgSi2O6, CaSiO3 and Na2MgSiO4, which indicated that the experimental sample was a multiphase ceramic system. Through the trend of bulk density as functions of the content of substitution and the change of SEM morphology, it could be found that appropriate amount of Na+ substitution can promote the grain growing and the densification of ceramics. Results demonstrated that both the Q × f and εr were relevant to bulk density and the second phase. The τf was also affected by the second phase to some extent. In particular, the ceramics sintered at 925 °C for 3h possessed the desirable microwave dielectric properties for LTCC application: εr = 7.03, Q × f = 17,956 GHz, and τf= −79 ppm/°C.
Effects of Cu substitution on microstructures and microwave dielectric properties of Li2ZnSiO4 ceramics
Authors: Zhang Qin , Su Hua , Tang Xiaoli
Published: January 2022

Herein, the influence of Cu2+ substitution on the phase composition, bulk density, microstructures, and microwave dielectric properties of Li2CuxZn1−xSiO4 (0 ≤ x ≤ 0.06) ceramics prepared by a solid-state reaction were investigated. The results of XRD and mapping showed that Cu2+ substitution can avoid the influence of secondary phase on the properties of samples. According to the analysis of bulk density, microstructure and microwave dielectric properties, a proper amount of Cu substitution not only improved the sintering characteristics of Li2CuxZn1−xSiO4 ceramics, reduced the densification temperature from 1250 °C to 950 °C, but also increased the Q×f value. Furthermore, Cu2+ substitution also improved the temperature stability of the samples. Particularly, the Li2Cu0.04Zn0.96SiO4 ceramics sintered at 950 °C for 5 h possessed excellent microwave dielectric properties: εr = 5.624, Q×f = 12,764 GHz, and τf = −77 ppm/°C, exhibiting a potential for the low temperature co-fired ceramic applications.
Research on material selection of force-sensitive element for high-frequency dynamic piezoelectric pressure sensor
Authors: Cai Sikang , Wang Guicong , Li Yingjun , Yang Xiaoqi
Published: January 2022

The high-frequency dynamic piezoelectric pressure sensor has the advantages of simple structure, long service life, high natural frequency, excellent signal-to-noise ratio and great sensitivity. It is appropriate for measuring high dynamic, dynamic or quasi-static pressure changes and pressure fluctuations. And this kind of sensor is widely utilized in the shock wave testing. The force-sensitive element is one of the main factors affecting the static and dynamic performance of piezoelectric pressure sensors. Basing on the piezoelectric equation and coupling effect between mechanics and electricity, in this paper, the finite element model of the high-frequency dynamic piezoelectric pressure sensor is established. The influences of the force-sensing element on the sensitivity of the sensor are analysed. Referential suggestions for choosing force-sensitive element of high-frequency dynamic piezoelectric pressure sensor are provided.
Experimental study on preparation of fuel by low-temperature pyrolysis of plastic waste combined with desiccated sludge after preforming
Authors: Jia Hongxin , Wang Jingfu , Ma Yasong
Published: January 2022

Take plastic waste and dried sludge as raw materials, use pressure testing machine and high temperature hot pressing mold to test under different parameters. The effect of raw material ratio, low-temperature pyrolysis temperature, molding pressure and heating time on the physical properties of the molded fuel after low-temperature pyrolysis, such as relaxation density, fall strength, compressive strength and water permeability, are studied. Single factor tests show that the general range of mixed molding parameters is: mixture ratio (dry sludge: composite plastics) 85:15~75:25, temperature 150~250°C, heating time 20~40min, compaction pressure 2~6MPa. Orthogonal test is designed on the basis of single factor test. The results show that the most important factor affecting the relaxation density of molding fuel is molding pressure, the most important factor affecting compressive strength is the ratio of raw materials, and the most important factor affecting water permeability is heating time. The fall strength is less affected by various factors. It is due to the stickiness of the molded plastic after softening, which strengthens the “cohesion” between the raw materials, and will not be explored in the orthogonal experiment. The optimal combination of relaxation density molding parameters is the ratio (dry sludge: composite plastics) 80:20, temperature 250°C, heating time 30min, compaction pressure 6MPa; the optimal combination of compressive strength molding parameters is 75:25, 250°C, 30min, 6MPa; the optimal combination of anti-moisture absorption performance molding parameters is 85:15, 150°C, 30min, 2MPa.
The patterns of traveling wave on shallow water modeled by Green-Naghdi equation
Authors: Wei Haitong
Published: January 2022

The Green-Naghdi equations are a shallow water waves model which play important roles in nonlinear wave fields. By using the trial equation method and the Complete discrimination system for the polynomial we obtained the classification of travelling wave patterns. Among those patterns, new singular patterns and double periodic patterns are obtained in the first time. And we draw the graphs which help us to understand the dynamics behaviors of the Green-Naghdi model intuitionally.
A blockchain-based cooperative modeling method for digital twin ontology model of the mechanical product
Authors: Zheng Menglei , Tian Ling
Published: January 2022

With the rapid increase of multi-source heterogeneous dynamic data of mechanical products, the digital twin technology is considered to be an important method to realize the deep integration of product data and intelligent manufacturing. As a digital archive of the physical entity in entire life cycle, the mechanical product digital twin model is cross-phased and multi-domain. Therefore, safe and stable cooperative modeling has become a basic technical problem that needs to be solved urgently. In this paper, we proposed a blockchain-based collaborative modeling method for the digital twin ontology model of mechanical products. First, an authorization network was constructed among stakeholders. Then modeling processes of the digital twin were mapped to ontology operations and formatted through extensible markup language. Finally, consensuses were obtained based on practical byzantine fault tolerance. And a material modification process of a helicopter damper bearing was taken as an example to verify. The proposed method enables all participants to accurately obtain the latest state of the digital twin model, and has the advantages of tamper-proof, traceability, and decentralization.
Simulation on adjacent line mutual interference of high-speed railway track circuit
Authors: Xiong Qihui , Yang Shiwu , Liu Chang
Published: January 2022

As the density of the high-speed railway network continues to increase, the problem of electromagnetic interference on adjacent lines has become increasingly prominent. This paper focuses on the electromagnetic interference of adjacent lines caused by rail and line in the signal transmission process of the high-speed rail track circuit. Firstly, complete the establishment of the four-terminal network model of the ZPW-2000A track circuit system and the cab signal entry current crosstalk model, calculation of interference voltage under different parallel length of signal frequency. Then the interference factors and coupling mechanism of adjacent lines are analysed to realize calculation of interference amount. Finally, according to the sensitivity index of the cab signal, the maximum parallel length of adjacent sections is given respect, and the interference protection suggestions of adjacent lines are put forward. The research work of this paper provides a theoretical basis for suppressing the interference of adjacent lines and guarantees the safe and efficient operation of high-speed trains.
Resident user load classification method based on improved Gaussian mixture model clustering
Authors: Wang Haojing , Tian Yingjie , Li An , Wu Jihai , Sun Gaiping
Published: January 2022

In view of the limitation of “hard assignment” of clusters in traditional clustering methods and the difficulty of meeting the requirements of clustering efficiency and clustering accuracy simultaneously in regard to massive data sets, a load classification method based on a Gaussian mixture model combining clustering and principal component analysis is proposed. The load data are fed into a Gaussian mixture model clustering algorithm after principal component analysis and dimensionality reduction to achieve classification of large-scale load datasets. The method in this paper is used to classify loads in the Canadian AMPds2 public dataset and is compared with K-Means, Gaussian mixed model clustering and other methods. The results show that the proposed method can not only achieve load classification more effectively and finely, but also save computational cost and improve computational efficiency.
Research on maintenance method of relay protection state based on combination weight and gray relation
Authors: Wang Xuanhang , Liang Zhijian
Published: January 2022

Relatively independent evaluation parameters are selected from many parameters through pedigree clustering.Learning the analytic hierarchy process (ahp) and entropy weight method can determine the weight, and at the same time to understand the error of the analytic hierarchy process (ahp) and entropy weight method is large, so the combination of the subjective and objective weight obtained by the two methods, using the improved entropy weight-ahp method to determine the weight. The improved weight calculation method has a clear hierarchical structure, which not only considers the influence of subjective and objective factors, but also makes full use of the weight information in the hierarchical structure. Considering the uncertainty of information, gray relation is adopted to deal with the data, so as to make maintenance rules.
Research and application of reliability-based cost optimization method for constant interval preventive maintenance
Authors: Zhang Tao , Qing Chen , Yu Na
Published: January 2022

Preventive maintenance is a means to ensure the component is kept in the desired state. Lack of preventive maintenance will cause unexpected consequences for the component, and too much preventive maintenance will result in unnecessary investment of resources. Based on the reliability data of the component, this paper establishes an analysis model to determine the optimal preventive maintenance interval of the component to make the cost of preventive and corrective maintenance lowest.
Knowledge extract and ontology construction method of assembly process text
Authors: Du Yimin , Shi Lingling , Zhai Xiang , Gong Hanqing , Zhang Zhijing
Published: January 2022

The actual product assembly process mainly relies on manual assembly by workers, and the personal experience of workers is difficult to effectively reuse. Ontology as a knowledge management and expression tool is gradually applied in the field of assembly. However, the manual construction of the ontology is time-consuming and labor-intensive, and the automatic construction of the ontology requires a large number of corpora for training, both of which are difficult to obtain a good assembly case ontology. This paper proposes a method in which automatically extracts relevant knowledge from case assembly process files to generates case database and integrates ontology framework of assembly domain to construct ontology. It shows that the accuracy can be guaranteed on the basis of the rapid construction of case ontology. The feasibility of this method is proved by a practical case.
Optimizing the distribution of food based on the vogel method
Authors: Chen Haoyan , Zheng Jiarui , Lao Linjiaming
Published: January 2022

Currently, numerous people still suffer from hungry and food insecurity. To solve the problem of production and distribution of food, we firstly set up a quantitative examination on food system from four dimensions, including equitability, efficiency, stability, and sustainability. As we choose 2 to 4 indexes for each dimension, we applied entropy weight method to decide the weight of each index. Secondly, we used BP neural network by MATLAB to simulate the rising trend of population based on the data of population in recent years, and predicted the population until 2030, which is about 8.5 million. In the same way, we forecast that food yield will maintain at 1.63*109 litres approximately till 2030 in the whole world. With certain assumptions, we set a model about Transportation Problem, which help us optimize the food transportation system at present. We use the Vogel method to calculate the results and chose 9 ports for exporting countries and 10 ports for importing countries. After that, we calculate the minimum costs of transportation all over the world is $4979628112343. At the end of our paper, we make sensitively analysis, the result of which proves that our model has a good stability.
Modeling and simulation: social force model modified by Helbing model in fast pass system
Authors: Zhang Ruiqi , Cao Yuting , Li Yuzhang
Published: January 2022

This paper introduced Helbing’s social force model, modified it with game theory. Then how individuals in the space behave in dynamic non-cooperative games was described, different macro grouping characteristics were obtained. Individual behaviours at the micro level were simulated. Setting different parameters and conditions of the model, the macro effects of individual behaviours were observed. The overall behaviour of the system was studied. It could be used to guide the allocation of public resources.
Impact of digital information systems on supply chain performance: a mediation of integrations and green practices
Authors: Abdul Rehman Khan Syed , Yu Zhang , Shah Adeel , Tanveer Muhammad
Published: January 2022

Industry Revolution (IR) 4.0 is revolutionizing the information infrastructure and the systems in supply chain management. However, the employment of the new technology is not sufficient to impact Supply Chain Management Performance (SCMP). Organizations need to build capabilities like integration both Upstream (UI) and Downstream (DI) for the technology to increase SCMP. The Green Practices (GP) are also becoming part of global corporate culture as all stakeholders demand sustainability in the value chain. The study tests IR 4.0, UI, DI, and GP to understand its impact and relationship with SCMP. For the statistical testing conducts on primary data collected from Malaysian firms. AMOS structural equation model is used to test the model and infer the results. The test concludes that IR 4.0 along with UI, DI, and GP impacts SCMP positively.
Impact of the epidemic on the world economy
Authors: Feng Zihuan , Liang Xun , Cai Binqing
Published: January 2022

The impact of the epidemic on the global economy has exposed the fragility and complexity of the internal and external economic system, and the global economic situation is not optimistic. Taking the epidemic as an example, this paper analyzed the impact of emergencies on the global economy from multiple perspectives. The outbreak of the epidemic has made most offline businesses shut down overnight. At the same time, it has also led to the rapid development of online economy, such as online education, home office software, video entertainment and so on. The outbreak and spread of the epidemic has promoted the digital upgrading of all walks of life, including online government affairs, commerce, science, education, culture and health organization, operation and maintenance. The era of digital economy has come, and digitization is the general trend.
Development and evaluation of healthy cities
Authors: Xia Kai , Yao Yuheng , Bu Zhizhen , Zhou Zhijun
Published: January 2022

The Healthy Cities and Sustainable Development Goals are interlinked, and the Healthy Cities movement has received widespread response and support worldwide over the past 30 years. The European Healthy Cities Networks covers about 1,400 cities. China started the Healthy Cities Movement in 1994 and put forward the Healthy China Strategy in the report of 19th national congress of CPC. Based on the impact of COVID-19 and Henan floods on urban health, it is necessary to incorporate some unconventional indicators into the Healthy Cities evaluation indicator framework. In addition, structured data cannot fully describe certain indicators, so the collection of unstructured data is equally important.
An empirical analysis of driving factors of Xi’an hub economic development
Authors: Wang Dan , Chen Cheng , Liu Junxia
Published: January 2022

In order to promote Xi’an’s economic development as an export-oriented hub, 7 indicators, including GDP, foreign trade volume, investment volume, passenger transport volume, freight volume, post and telecommunications business income, and the number of industrial enterprises above designated size, are selected to analyze the development of the hub economy through multiple linear regression analysis method. The results show that foreign trade, passenger traffic and post and telecommunications business revenues are significant to the economic development of Xi’an hub. However, the freight volume, investment and the number of enterprises above designated size have not passed the inspection. According to self-organization theory, the countermeasures for Xi’an to develop the hub economy are puts forward.
Evaluation of economic recovery capability under the background of COVID-19: application of a big data information processing model
Authors: Shi Yufeng , Tang Jiaohui , Wan Dan
Published: January 2022

In order to promote local economic recovery under the COVID-19 pandemic, this paper first constructs a big data information processing model, then measure the growth of GDP and fiscal revenue driven by consumption, investment and export in Guangdong province. The measurement results show that under the stimulus of consumption, investment and export of the same intensity, Guangzhou, Shenzhen and Foshan perform better in the GDP index, while Shenzhen, Shaoguan and Qingyuan perform better in the fiscal revenue index. To this end, local governments should give priority to Guangzhou, Shenzhen, Foshan, Shaoguan and Qingyuan to take effective economic stimulus measures to achieve faster growth in GDP and fiscal revenue. The research results are of practical significance for guiding local governments to implement precise policies to promote the process of economic recovery.
Study on the marketing of rural tourism destination based on the internet perspective
Authors: Cheng Congxi , Zhang Yangyang , Luo Sha , Yang Wenjing , Guo Yulu , Yu Hanli , Kang Jinqian
Published: January 2022

With the rapid development of the rural tourism in China, how to innovate and optimize the marketing mode and successfully achieve the marketing purpose is an urgent problem for the marketing of the rural tourism destination. The rapid development of Internet technology has provided new ideas for rural tourism destination marketing. Based on the analysis of the questionnaire results of rural tourists, this paper has proposed the optimization suggestions of rural tourism destination marketing from the Internet perspective. That is, building the information communication channel between rural tourism destinations and tourists based on the Internet, designing tourism products of the rural tourism destination on the basis of tourist characteristics of tourists and realizing the marketing optimization of rural tourism destinations with the help of Internet technology.
“Internet + Tourisim” promotes the research on the inheritance and development of Jinan spring culture
Authors: Dong Xiangli
Published: January 2022

With the rapid development of Internet technology, “Internet +” has enabled the development of tourism and helped the transformation and upgrading of tourism. Cultural tourism is having a profound impact on cultural inheritance and development. This paper aims to promote Ji ‘nan Spring Culture to move towards the direction of smart tourism by the deep integration of “Internet + Tourism”. Discuss reasonable and feasible inheritance, development and protection strategies. To solve the problems existing in the development of Spring Culture and tourism, protect and inherit the features of Spring Culture, and promote the orderly and healthy development of Spring Culture in Jinan.
Dynamic monitoring and evaluation of ecological restoration in mining area based on GNSS+RS technology
Authors: Wang Qiang
Published: January 2022

The continuous development of mineral resources is increasingly damaging the ecological environment, so it is of great significance to ecological restoration and dynamic monitoring of the mining area. In this paper, dynamic monitoring and evaluation method of ecological restoration in the mining area are proposed, which integrates GNSS + RS (Global Navigation Satellite System + Remote Sensing) technology. According to the Precipitable Water Vapor (PWV) retrieved by GNSS and NDVI (Normalized Vegetation Index) can monitor the ecological environment and introduce machine learning to improve the accuracy of the model. The dynamic assessment of ecological restoration was carried out by using temperature, rainfall, NPP (Net Primary Productivity), NDVI and PWV. The results show that: (1) the modeling effect of machine learning is better than that of the least square regression. (2) The comprehensive ecological evaluation index proposed can better reflect the ecological situation of the mining area. Therefore, the environmental monitoring and assessment of mining area based on GNNS + RS technology proposed in this paper have important reference significance.
Investigation on form and energy use of the rural residences in Beijing and surrounding cold areas under the self-sufficiency perspective
Authors: Gao Wei , Zhao Mei , Li Huihua
Published: January 2022

As a design theory on energy-saving housing, Self-sufficiency house is suited to the environment conditions of cold rural areas in China. Investigation on the rural residence form and energy use is the important foundation to carry out the research and design practice on self-sufficiency house. Taking Beijing and its surrounding rural areas as target, the paper combs current situation and technical requirements of rural residence based on self-sufficiency perspective. After surveying general residential condition and data, it analyzes the form, function, energy use and heating technology of rural residence, which will provide basic data and reference for post-study.
Analysis of dynamic model based on pedestrian’s abnormal posture
Authors: Zhao Rongyong , Jia Ping , Han Chuanfeng , Wang Yan , Li Cuiling , Zhang Zhishu
Published: January 2022

It is significant to detect abnormal postures of pedestrians in the crowd to crowd stability control. This study locates the joint points of pedestrians based on the pose estimation algorithm OpenPose. After the analysis of 18 nodes and six body parts, the sudden value of node acceleration is obtained, which is compared with the acceleration of the pedestrian’s centre of mass. When there is at least one difference in the direction or acceleration value of the two, it means that the pedestrian has abnormal behaviour. Furthermore, this study analyses the result of comparing the change of z-coordinate value in pedestrian movement with 20% of pedestrian height. These two judgment methods together constitute the dynamic criterion of pedestrian abnormal posture, and judge whether the pedestrian has abnormal behaviour. Compared with the previous dynamic analysis of pedestrian abnormal posture, the accuracy of abnormal posture judgment is improved. This provides a theoretical basis for crowd stability analysis.
Research on food safety prediction method based on k-means clustering algorithm
Authors: Wu Mengjuan , Jiang Huan
Published: January 2022

Aiming at the problem of food risk prediction, this paper proposes a method based on clustering algorithm to predict product risk by raw material risk. Firstly, based on the provincial supply chain closed-loop hypothesis, this paper proposes the selection method of clustering indexes for products and their raw materials. Secondly, this paper uses the k-means clustering algorithm to cluster the products and the corresponding raw materials respectively, then based on the clustering Class results automatically determine the high-risk categories of the products and their raw materials. Finally, the analysis of the experimental data of the 8 categories of products and their raw materials shows that the ratio of the high-risk categories of products and the ratios of the corresponding high-risk categories of raw materials have a strong positive correlation. The experimental results prove the rationality of the raw material clustering index selection method proposed in this paper and the correctness of the method of predicting product risk based on the raw material risk based on the clustering algorithm.
Prediction of PM2.5 concentration based on BP neural network optimized by bee colony algorithm
Authors: Heng Jie , Li Min
Published: January 2022

According to the ambient air pollutants data and meteorological conditions data of Mianyang City in 2017, the BP neural network model based on MATLAB is established to predict the daily average PM2.5 concentration of Mianyang City in the next two days. However, the traditional BP network has the disadvantages of slow convergence speed and easy to fall into local optimum. In order to improve the prediction accuracy of the model, an optimization algorithm is added to the prediction model to avoid the model falling into local minimum. In this paper, the bee colony algorithm is added to the prediction model to improve the accuracy of BP neural network prediction model. The data from January to November are used for training, and the data from December are used as the verification results. The results show that the optimization model can accurately predict the daily average PM2.5 concentration of Mianyang City in the next two days, which provides a new idea for the prediction of PM2.5 concentration of the city, provides a theoretical basis for the early warning and decision-making of air pollution, and also provides more reliable prediction services for people’s daily travel.
3D reconstruction of human body model based on incremental Motion recovery structure
Authors: Zhang Shiheng , Zhang Shaopeng , Chen Jianyang , Wang Xiuling
Published: January 2022

3D reconstruction of human body model is a very important research topic in 3D reconstruction and also a challenging research direction in engineering field. In this paper, the whole pipeline flow of 3D reconstruction of human body model based on incremental motion recovery structure is proposed. Use mobile phone to collect images from different angles and screen them; Secondly, feature extraction and matching under SIFT operator, sparse reconstruction of incremental motion recovery structure, dense reconstruction based on depth map and other processes are carried out. Poisson surface reconstruction is finally carried out to achieve model reconstruction. Experiments show that the effect subject of the reconstructed model is clear.
Identification of internal cracks in corn seed using convolutional neural networks
Authors: Huang Ziliang , Wang Rujing , Wang Liusan , Teng Yue , Zheng Shijian
Published: January 2022

The identification of seed quality is very important for which the quality of seed is crucial to the yield and quality of crops. There are two main problems with the acquisition and identification of cracks inside corn seed. One is that most of the methods of near-infrared spectroscopy or X-ray are used to obtain images of cracks inside the seed, the acquisition equipment is expensive and the operation is complicated. The other is the identification of crack images, and the traditional image processing method is usually used which requires professionals to design different model parameters each time, resulting in poor model robustness and low model accuracy. In this study, we originally proposed a simple but effective method to obtain the picture of corn seed internal cracks, which is combined with visible light transmission and ordinary camera acquisition method. We also proposed using the transfer learning methods not only solving the problem of the small scale of our corn seed internal cracks dataset but also avoiding extracting features manually. Our proposed method achieved a promising result, which is able to correctly identify the cracked and intact corn seed 100% in our training stage and testing stage.
The design of following controller for autonomous vehicle based on leader-follower strategies
Authors: Li Hongyang , Li Hailiang , Li Ziyi
Published: January 2022

Aiming at the problem of following control of autonomous vehicle, the following controller is designed based on Leader-follower strategies. First, the kinematic modeling is done. Next, Leader-follower model is used to describe the following structure and L − ϕ method is used to build error system. Then, The speed controller for the follower is designed to achieve the objectives. Finally, the simulation is done by Matlab, the results show that the controller is effective.
A close-loop verification approach for pedestrian stability based on machine vision
Authors: Zhao Rongyong , Jia Ping , Wang Yan , Li Cuiling , Ma Yunlong , Zhang Zhishu
Published: January 2022

In public places, it is significant to analyze the stability of the crowd which can support the crowd management and control, and protect the evacuees safely and effectively. The numerical analysis method of system stability based on Lyapunov theory suffers problems that it is difficult to avoid random errors in the initialization of pedestrian density and velocity, as well as cumulative errors due to time increasing, limiting its application. This study adopts a complementary model of theoretical numerical analysis and machine vision with a parallel convolutional neural network (CNN) model. It proposes an approach of stability analysis and closed-loop verification for crowd merging systems. Thereby, this research provides theoretical and methodological support for planning of the functional layout of crowd flow in public crowd-gathering places and the control measures for stable crowd flow.
Computational intelligence model based on GA-BP neural network
Authors: Zhang Chengzhao
Published: January 2022

Since the birth of the secondary stock market, the prediction of the stock price trend has become a research direction concerned by many people. Aiming at the problem of non-stationary and non-linear stock price forecasting, this paper builds a computational intelligence model to improve the neural network with genetic algorithm. The results show that, compared with other models, the GA-BP neural network model proposed in this article can effectively improve the prediction of the rise and fall of the HS300 index, and the withdrawal range is small when the market falls. The research of this paper enriches the method of financial time series data analysis, which can not only provide decision-making reference for investors, but also help to enhance the cognition of financial market rules. The model can significantly reduce the forecast error and improve the model fitting ability.
Design and implementation of children’s gesture education games based on AI gesture recognition technology
Authors: Zhong Yushan , Jia Yifan , Ma Liang
Published: January 2022

In order to cultivate children’s imagination and creativity in the cognitive process, combined with the traditional hand shadow game, a children’s gesture education game based on AI gesture recognition technology is designed and developed. The game uses unity development platform, with children’s digital gesture recognition as the content, designs and implements the basic functions involved in the game, including AI gesture recognition function, character animation function, interface interaction function, AR photo taking function and question answering system function. The game is finally released on the mobile terminal. Players can recognize gestures through mobile cameras, interact with virtual cartoon characters in the game, watch cartoon character animation, understand popular science knowledge, and complete the answers in the game. The educational games can better assist children to learn digital gestures, enrich children’s ways of cognition, expand children’s imagination, and let children learn easily with happy educational games.
Modeling of the Marine atmosphere and its impact on Ka-band channels
Authors: Liu Zheng , Sun Fu-an , Zhou Bin
Published: January 2022

The sea atmosphere environment will affect the Ka frequency channel in TT&C. Firstly, this paper briefly introduces the Marine atmospheric environment. Attenuation models of water vapor solubility and rainfall intensity are established. The variation characteristics of atmospheric environment and the estimation method of rainfall intensity are studied. Finally, the influence of Marine atmosphere on Ka-band channel is simulated and analyzed. The simulation results show that different elevation angles have different effects on Ka-band channels. The influence result decreases gradually with the elevation Angle increasing.
A study on radiotelephony English test design
Authors: Dai Lixin
Published: January 2022

Radiotelephony English is taught in college for the learners whose future professions are mainly pilots and air traffic controllers. The present study is to analyse the radiotelephony English test design in a university to see the extent of which it evaluates learners’ communicative competence in aviation scope. Theoretical frameworks on communicative competence, modern test theory and ICAO language proficiency requirements for the learners of radiotelephony communication are presented. The study reveals that learners’ communicative competence which includes both radiotelephony and everyday communication skills are important components in radiotelephony test design. The study points out that the application of modern test theory in designing radiotelephony test in college is vital in meeting the validity and reliability of the test and the students’ individual needs in English language learning for future career needs to be reflected in the test design.
A novel cache based on dynamic mapping against speculative execution attacks
Authors: Wu Dehua , Xiao Wan’ang , Gao Shan , Gao Wanlin
Published: January 2022

The Spectre attacks exploit the speculative execution vulnerabilities to exfiltrate private information by building a leakage channel. Creation of a leakage channel is the basic element for spectre attacks, among which the cache-tag side channel is considered to be the most serious one. To block the leakage channels, a novel cache applies Dynamic Mapping technology, named DmCache, is presented in this paper. DmCache applies a dynamic mapping mechanism to temporarily store all the cache lines polluted by speculative execution and keep invisible when accessing. Then it monitors the head of the reorder buffer to determine which polluted cache line can become visible. In this paper, we demonstrated that Spectre attacks exerted no impact on a processor system equipped with DmCache based on the analysis of the processor’s circuit behaviour, which equipped with the DmCache and under the Spectre attack.
Research on online teaching platform system based on microservice architecture
Authors: Gu Huijie , Yang Shulin , Gu Mengdie , Yuan Ming
Published: January 2022

The traditional online teaching adopts the single architecture to develop and implement the system, which facilitates the data sharing and testing of the system. However, due to the increasing complexity of the system's business functions, the system based on monolithic architecture has become increasingly complex, its scalability has deteriorated, and its concurrency performance has decreased. Based on these problems, this paper puts forward combining microservice architecture and online teaching platform, using microservice architecture independent deployment, concurrent performance characteristics such as high technology selection and flexible, the complex business function is divided into several small service module, solve the challenges faced by the traditional system, at the same time improve the efficiency of the use of online teaching platform and students' learning autonomy, The system function design, architecture design, safety design and so on are expounded to build an efficient and perfect online teaching platform.
Evaluation of teaching quality based on binary tree support vector machine
Authors: Wu Xinghui , Shi Zaifeng , Xing Haihua , Xue Yisheng
Published: January 2022

In order to solve the reliability of the evaluation results of teaching quality in universities and colleges, an improved model of teaching evaluation based on the Support vector machine was put forward. In this model, the evaluator does not need to give an evaluation result of the teacher’s teaching quality, but gives the score of each evaluation index, and then calls the Support vector machine, automatic classification of teachers’ teaching quality. The experiment proves that the improved algorithm can improve the teaching quality evaluation accuracy and the result is better.
Adaptive RBF -SMC control for multi-point mooring system
Authors: Lu Run , Zhang Guichen , Shi Jianqiang
Published: January 2022

A stable adaptive control scheme for multi-point mooring system (MPMS) with uncertain dynamics is proposed in this paper. The control scheme is designed by a hybrid controller based on RBF (Radial Basis Function) NN (Neural Network) and SMC (Sliding Mode Control), which learns the MPMS dynamic changes, and the compensation of external disturbances is realized through adaptive RBFNN control. Meanwhile the RBF-SMC control parameters are adapted by the Lyapunov method to minimize squares dynamic positioning (DP) error. The convergence of the hybrid controller is proved theoretically, and the proposed mooring control scheme is applied to the “Kantan3” mooring simulation system. Finally, the simulation results are compared with the traditional PID controller and standard RBF controller to demonstrate the effective mooring positioning performance of the control scheme for the MPMS.