bluuebunny/crossref_metadata_2025_split huggingface dataset:
The research on continuous carrier phase time transfer method based on parameter transfer
Authors: Wang Jiang-Ting , Xu Jing-Xuan , Wang Xiang-Lei 
Published: June 2021

Abstract
The method of continuous GNSS carrier phase time transfer is studied in detail, and the cause of jump in carrier phase time transfer results is analyzed. The relationship between multi-day data jump and daily jump is deduced in theory, and the correctness of the deduced result is verified by the calculation result of actual measured data. Solution is given to daily jump in carrier phase time transfer. Since the time transfer reference signal is a continuously running high-precision atomic clock signal, a continuous PPP time transfer method based on clock difference parameter transfer is proposed. The method proposed in this paper is validated and analyzed with the actual measured data, and compared with the traditional GNSS carrier phase time transfer solution. The results show that the method given in this paper can solve the problem of daily jump jump to a certain extent, effectively improve the continuity, availability and reliability of time transfer results, and also improve the frequency stability of time transfer results.
Analysis of Image Registration Algorithm RANSAC and Its Improved Algorithm
Authors: Pan Zhongtai , Wen Zhenwei 
Published: June 2021

Abstract
The RANSAC (random sampling consensus) algorithm is an estimation method that can obtain the optimal model in samples containing a lot of abnormal data. This algorithm uses a small number of points in the data to estimate the model, and then uses the remaining points to check the model. It is now widely used in computer vision image stitching. This algorithm has disadvantages such as slow operation speed and poor sample adaptability. In order to improve the efficiency of image registration, many researchers have made improvements on the basis of the RANSAC principle. This article introduces the principles and shortcomings of RANSAC, and introduces four ways to improve it in view of its shortcomings. The advantages and problems of the improved algorithm are analyzed to provide a basis for the field of image registration.
Remote Sensing Monitoring of Vegetation Coverage of Hunshandake Sand Based on HJ-1A
Authors: Feng Tianshi , Wang Zhiguo , Pang Zhiguo , Jiang Wei , Li Hao 
Published: June 2021

Abstract
Hunshandake Sand has sparse vegetation and serious desertification, which is one of the main reasons for the dust weather in the Beijing-Tianjin-Hebei region. Dynamic monitoring of vegetation coverage in this area is of great significance for predicting sand and dust weather in the Beijing-Tianjin-Hebei region. Remote sensing technology has the advantages of large area, multiple time phases, and high accuracy. This study is based on the CCD data of the HJ-1A, using NDVI parameters as the main input parameters, and using an improved pixel binary model to invert the vegetation coverage of the study area. On this basis, the land use type data is used to extract another vegetation coverage of the study area during the period. The vegetation coverage in different periods of the study area is calculated by band to achieve the purpose of dynamic monitoring. The results show that desertification is common in the northwest of the study area, and the vegetation coverage is becoming lower and lower, while the vegetation coverage in the northeast and south is increasing, and the overall vegetation coverage in the study area is increasing. The experimental results are more consistent with the actual situation, which confirms that the improved pixel binary model has higher accuracy and a certain degree of universality, and the overall desertification control effect of the Hunshandake Sand is better.
Light deflection Phenomenon Simulation and Calibration of the Earth-Observation Satellite
Authors: Yu Jing , Liang Deyin , Gao Hongtao , Yu Longjiang , Huang Yufei 
Published: June 2021

Abstract
The advance of the resolution of optical observation satellite requires more accurate image acquisition location and geometrical model, therefore, light deflection effect must be taken into account in the geometrical model. The deflection of light is a phenomenon of a deviation between the apparent position and the true position of the observed object, due to the relative velocity of the observer (the remote sensing satellite). This article firstly models the light deflection effect of the earth-observation process of satellite, using this model, the deviation of the “apparent” location and the “real” location of the ground target is calculated. Then the influence of the satellite observation pointing angle to light deflection effect is analyzed. In the end, the correction method of the light deflection effect is advised, and through emulation, we can see that the image acquisition location error can be greatly improved after the correction.
The technology of effective reservoir prediction in fault development zone
Authors: Jiang Zhenhai 
Published: June 2021

Abstract
Reservoir prediction in the middle and late stages of development is not only to predict the sandstone, but also to define the specific location of Petroleum-bearing sandstone. The post-stack seismic data is superimposed on a multi-channel seismic data level, although the signal-to-noise ratio is improved to a certain extent, the average amplitude value is obtained in the superposition process, so that only the effective prediction of the sand body can be realized. However, the pre-stack seismic data can obtain the information of shear wave by the longitudinal wave. The characteristics of the shear wave that cannot propagate in the fluid can effectively predict the reservoir and fluid distribution. In order to further quantify the remaining oil potential in fault area, prestack seismic inversion technology and petrophysical analysis are used to determine the favorable oil-bearing area. On this basis, prestack geostatistical inversion is completed to further clarify sand body with high oil saturation. Combined with numerical simulation, it effectively predicts the residual oil distribution at the edge of fault and the precision of the remaining oil quantitative characterization results is high. The recognition rate of thick layer saturation is more than 90%, and the recognition rate of thin interlayer saturation is more than 70%, which can meet the demand of fine reservoir prediction.
Spatiotemporal Variations of Aksai Chin Lake and its influencing factors during 1972-2018
Authors: Yan Wei , Jiang Ziyun , Zhou Feng , Ning Jia , Hou Shuangshuang , Wang Jian , Han Rumeng , Liu Minghua 
Published: June 2021

Abstract
In the context of increasing lake expansion on the Tibetan Plateau, which is sensitive to climate change, it is of great significance to strengthen the research on the characteristics of lake change and its response to climate change. This paper was designed to investigate the spatiotemporal variations of Aksai Chin Lake (ACL), a typical large lake on the Tibetan Plateau, by using Landsat MSS/TM/ETM+/OLI images during 1972-2018, and to quantitatively discuss the effects of climate on lake changes based on meteorological data from Shiquanhe station. During 1961-2018, annual mean air temperature and precipitation in this region increased at rates of 0.44 °C/decade and 1.35 mm/decade, respectively, with a mutation point of 1999 for temperature, while evaporation decreased at the rate of -54.3 mm/decade, with two mutation points in 1972 and 2014, respectively. The area of ACL had increased at an average rate of 2.51 km2 per year, with a fluctuation of “slight expansion – shrinkage – rapid expansion – slight expansion – rapid expansion” during 1972-2018. Controlled by the topography, the ACL expanded to the southeast by 3851.6 m in total. In terms of the lake area response to climate change, air temperature and evaporation were the main factors affecting ACL area directly, while precipitation mainly regulated ACL by the indirect effect through air temperature and evaporation. Generally, rising air temperature, increasing precipitation and decreasing evaporation all contribute to promote the expansion of ACL.
Collection Method of Arbitrary Laser Echo Based on STM32
Authors: Li Weihao , Zhou Guoqing , Zhou Xiang , Tan Yizhi , Lin Gangchao , Li Xianxing , Deng Ronghua 
Published: June 2021

Abstract
When LIDAR measures the water depth, in most cases the echo signal is more complex, with more backscattering, and it is difficult to observe different parts of the waveform separately, especially the underwater echo signal. Therefore, this paper uses an STM32 controller to design a signal generator to send out pulse signals, which act on the detection device PMT in the LIDAR detection system to control the start and stop of the PMT receiving channel. By adjusting the frequency, duty cycle, and other parameters of this signal generator, the arbitrary part of the waveform can be collected, and the waveform is not disturbed. Using the STM32 instead of a traditional signal generator can reduce system power consumption and load capacity.
Application of 3D Laser Scanning Technology in Monitoring Deformation of Port Trail
Authors: Dang Xiaobin 
Published: June 2021

Abstract
Qinhuangdao Port, as the main hub port for coal transportation from north to south, has become an important coal, oil and other energy export port in China. The port facilities are in continuous operation all the year round, especially in the peak period of coal transportation in the south. The maintenance and monitoring of the equipment are faced with such problems as heavy work tasks, poor working environment, many construction disturbances, and the influence of monitoring on port production. This paper mainly introduces the application of ground 3D laser scanner in building deformation measurement based on the deformation measurement project of positioning car cable track in the unloading department of coal terminal of Qinhuangdao Port. Through actual results illustrate using the ground three-dimensional laser scanner for high-risk, complex structure deformation monitoring operation is of field operation is simple, short construction period, small impact on the continuity of production equipment, complete data and reliable advantages of accuracy, which is the ground three-dimensional laser scanner in Qinhuangdao port for the first time application, for the future of 3 d laser scanning technology in the port risk measuring project and digital 3 d modeling and so on has certain reference value.
Criteria Determining the Number of Estimate Points of Moment Method for Performance Functions Including Non-differentiable Points
Authors: Wang Ruotong , Yu Zhiran , Wang Junjie 
Published: June 2021

Abstract
Moment method is famous for its calculation efficiency. Moments of the performance function are obtained by point estimates based on Hermite Integration. The reliability index and probability of failure can be obtained using existing standardization function or existing distribution systems. The precision of moment method increases monotonously with the increasing number of estimating points. The performance functions with non-differentiable points are frequently encountered when elasto-plastic behavior dominates for a structure under loading. Thus the accuracy and efficiency of moment method should be addressed for performance functions with non-differentiable points. In this paper, an example of structural performance functions is presented to show the existence of non-differentiable points. Two example performance functions are used to verify the accuracy and efficiency of moment method. The MCS method is employed to obtain the accurate results of probability of failure. The relative errors of probability of failure from moment method are obtained through a comparison with the results from MCS method. The fluctuation of the relative errors with the number of estimate points is also presented. The required number of estimate points for performance functions with non-differentiable points is discussed through the above two examples. Finally, criteria to determine the estimate points for performance functions with non-differentiable points are proposed and verified the applicability.
Research on response characteristics of weighing sensor of mixing vessel under medium and long period surge
Authors: Zhang Yipeng , Yang Xiuli , Li Dongdong , Fan Chenyang 
Published: June 2021

Abstract
Under surge condition, the composite motion of heave, roll, pitch, sway and surge occurs in the concrete mixing vessel, which affects the measurement accuracy of the load cell. Taking the S-shaped load cell as the test object, the measurement accuracy of the load cell under the condition of complex force field is tested by using the six degree of freedom test platform to simulate the medium and long period surge sea conditions. The test results show that: the measured value of the load cell is affected by the sway acceleration, the surge acceleration and the heave acceleration, and is positively correlated with them; when the meaningful wave height is 1m and the average zero crossing period is 6 ∼ 10s, the direct weighing accuracy of the concrete mixing vessel can not meet the requirements of the domestic standard.
Monitoring and Analysis of Subway Shaft Construction Displacement
Authors: Rui-juan Yang , You-Sheng Deng , Tao Liu , Yun-He Sun 
Published: June 2021

Abstract
According to the construction site monitoring of a subway tunnel shaft in Beijing, the deformation laws of surface settlement, horizontal displacement and vertical displacement of retaining structure during shaft construction were analyzed. The results show that: firstly, the ground settlement around the shaft can be divided into two stages, the rapid settlement stage before the floor construction and the stable settlement stage after the floor construction. The settlement rate and value of the middle point of the long side of the shaft is faster and bigger than the corner point and the middle point of the short side. The settlement value first increases and then decreases with the increase of the distance to the pit side. The maximum settlement is located at (0.61 ∼ 1) times the excavation depth behind the diaphragm wall. Secondly, the horizontal deformation of the long side of diaphragm wall is obviously different from the short side. The horizontal deformation of the long side is larger than the short side, and the position of the maximum horizontal deformation is deeper than the short side. The horizontal deformation curve of the middle point of the long side has obvious inflection point, and the middle point of the short side presents reciprocating type. The variation range of horizontal displacement of diaphragm wall top is between 10 mm, and the maximum horizontal displacement is 0.037% of shaft depth. Finally, the vertical displacement of the top of the diaphragm wall settles rapidly before the excavation of the bottom plate, and the settlement value decreases gradually after the excavation, and the increase rate of the diaphragm wall settlement is the largest when it is excavated to the bottom of the shaft. This deformation law can provide reference for the optimization of support design of similar projects.
Research on the application of BDS/GIS/RS technology in the high speed railway infrastructure maintenance
Authors: Yang Jianfeng , Bai Xuejiao , Zhang Zhuoxin , Yang Meihao , Pan Peifen , Liu Tao , He Lijun , Zhang Jifeng , Tao Tao 
Published: June 2021

Abstract
The high-speed railway infrastructure maintenance is the key to ensure the safe operation of the railway. The technical characteristics and advantages of Beidou Navigation Satellite System (BDS), Geographic Information System (GIS), and Remote Sensing (RS) are analysed for integrated application based on the practical application of professional engineering infrastructure monitoring, equipment inspection, disaster prevention and warning, workers management and time synchronization, and the solution of intelligent monitoring system for high-speed railway infrastructure maintenance was proposed. And this system supports visual display of vector and electronic map, status query of workers, trains, equipment and infrastructure for remotely monitoring, detecting and managing, which can provide low-cost, reliable and accurate information services for the security monitoring and management of the high-speed railway infrastructure maintenance.
To the question of the dependence of the change in the speed of ultrasound and the natural frequency of vibration of atoms in monatomic planes during a polymorphic transition in iron
Authors: Yurchenko Stepan A 
Published: June 2021

Abstract
Iron is one of the most used metals in industry and construction. Machines and mechanisms made of iron operate over a wide range of temperatures and voltages. Checking their performance during operation is carried out using non-destructive testing. One of the methods of non-destructive testing is the method of molecular acoustics, which links the internal structure and physical and mechanical characteristics with the values of the longitudinal and transverse ultrasound velocity. The change in the speed of sound upon deformation of the material is characterized by a change in the number of defects in the crystal lattice or by the rotation of mesoscopic volumes. However, a change in the speed of ultrasound also occurs during polymorphic transformation, which is associated with a change in the geometric dimensions of the cell of the crystal lattice and can be both under the influence of temperature and under pressure. Therefore, when analyzing a material by the method of molecular acoustics, it is necessary to understand what exactly happened in the material - a polymorphic transition or an accumulation of defects. This is possible only with an accurate determination of two parameters - the natural frequency of atomic vibration, which changes during the polymorphic transition, and a change in the ultrasonic wave velocity due to a change in the interatomic interaction of atomic shells. Therefore, the main goal of this work is to derive a theoretical equation relating the change in the natural vibration frequency of atoms during the polymorphic transition of iron from aFe to yFe, with a change in the specific area per atom in the atomic plane.
Analytical study of the non-stationary temperature field of a thermally thin plate
Authors: Latypov I I , Bigaeva L A , Mukhametshina G S , Shaikhutdinova N A , Gilev A Y 
Published: June 2021

Abstract
The report analytically investigates the unsteady temperature field of a plate experiencing intense thermal action. The problem is reduced to solving a singularly perturbed boundary value problem of the nonstationary thermal conductivity equation with nonlinear boundary conditions on movable borders. The approximate solution of which is obtained in the form of an asymptotic decomposition of the solution in the sense of Poincaré in degrees of small parameters, depending on the proximity of the point under consideration to the borders.
Metric transformation of the surface of a tight punch for forming sheet shells of double curvature
Authors: Mikheev V A , Grechnikov F V , Alvarenga Roberto de , Bodrov V V 
Published: June 2021

Abstract
For the first time, the problem of parametric reduction of the circumscribing surface of the shell of double curvature to the main axes and to the planes of symmetry defined by Gaussian coordinates is considered in detail. The solution of this problem is essential for ensuring the conditions of symmetrical shaping of the double-curvature circumflex shells by tight fit. The tight punch is presented in the form of a technological electronic layout, containing metric information of the surface of double curvature and storing information of the geometric alignment of the skin that extends to the outer circumferential surface of the unit. In this case, the circumferential surface of the shell of double curvature remains invariant with respect to the coordinate transformation.
Effect of tungsten nanoparticles on interaction of Sn-Cu-Co metallic matrices with diamond
Authors: Ozolin A V , Sokolov E G , Golius D A 
Published: June 2021

Abstract
The effect of tungsten nanoparticles on interaction of sintered Sn-Cu-Co metallic matrices with diamond has been studied. Nanoparticles were obtained by grinding standard tungsten powder in a planetary-centrifugal mill. Commercially pure tin, copper, and cobalt powders were mixed with synthetic diamonds and the milled tungsten. Samples were shaped by static pressing in a mold and sintered in vacuum at 820°C. The sintered samples were subjected to static compression test, and hardness of the metallic matrices was measured. The structure of fractures and distribution of the elements over them were explored by the SEM and energy dispersive X-ray microanalysis methods. It has been determined that introducing tungsten nanoparticles into the composite material contributes to dispersion hardening of the metallic matrix and higher strength of its adhesion to diamond.
Review of previous Russian studies in the abrasive flow machining
Authors: Levko V A , Litovka O V , Savin D I , Terjaev N S 
Published: June 2021

Abstract
Abrasive flow machining (abrasive flow machining (AFM)) is increasingly used worldwide. It is used for finishing and removing surface stresses in parts, the finishing machining of which using traditional methods is difficult. By now there are a large number of publications on this topic. A special interest are the articles in which previous works on various aspects of this technology are systematized. Due to a number of reasons, there are no publications from the scientific periodicals of Russia. This article presents a review of the works of Russian researchers in modelling the machining process by abrasive flow. They are aimed at modelling the rheological characteristics of the medium and contact interactions in processing. Particular attention is paid to the machining of an abrasive flow with an aligning device, as well as parts from powder molybdenum. The purpose of this article is to acquaint the wide range of readers with the works of Russian studies in the treatment of the abrasive flow of high viscosity medium.
Methods to improve vibroacoustic characteristics of mining machines
Authors: Podgorny A I , Kudrevatykh A V , Kudrevatykh N V , Ashcheulov A S , Ashcheulova A S 
Published: June 2021

Abstract
At machine-building enterprises, serious attention is paid to the issue of improving the products quality. Noise and vibration are one of the main indicators that characterize the quality, comfort and reliability of machines, so the reduction of noise and vibration level is one of the most important scientific and technical problems of national engineering. Along with the economic aspects, the reduction of machine noise contributes to the ecological state improvement, as well as the working and living conditions of workers. Noise and vibration are one of the most common adverse factors that worsen working conditions in production, construction and transportation.
Development and verification of a mathematical model of heating after the metal sample transition to a liquid-solid state in the turbine blades casting process
Authors: Vdovin R A , Kyarimov R R 
Published: June 2021

Abstract
The paper presents the results of the development of a mathematical model of the melting zone of a discrete-continuous casting installation, and also shows the verification of the results of computer modelling obtained using the developed mathematical model. An important feature of the developed mathematical model is the ability to calculate heat fluxes and temperature fields for all elements of the technological system furnace-flask-filler-mold-metal.