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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the analysis of operation system capability testing and evaluation, this paper studies the data resource system of operation system capability testing and evaluation from operation, business and engineering aspects. A 3-View Data resource framework is presented. And some suggestions on data resource construction are given. The research can help to clarify the data needs, improve the consistent understanding of joint operation system capability evaluation data, and promote the development of the data resource and data integrated service platform. [ABSTRACT FROM AUTHOR]

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the continuous improvement of 5G standards, 5G network equipment of global mobile operators has become mature. China's railways take 5G as a new generation of mobile communication technology for railway dedicated network, the R&D of railway application equipment is under way, and the 5G-R equipment interoperation test needs to be started urgently to provide conditions for the deployment of future 5G-R system. Based on the system architecture of 5G-R network and the theory of interoperation test, this paper presents the test architecture of 5G-R interoperation, innovatively puts forward one test method named the building block to set up processes for the verified 5G-R system described in the test architecture. According to the building process of the building block method, this paper lists the interoperation test interface and key test content of the test interface for the equipment to be tested, offers the design process of the interoperation test specification and the test framework of interoperation static and dynamic test environment. [ABSTRACT FROM AUTHOR]

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Real-time detection of the distance between trains is an important way to ensure the safety of rail transit and improve train capacity. In particular, the distance measurement between trains on curved rails is difficult to distance measurement. In order to calculate and optimize the real-time distance measurement formula of the train at the curve, a method of distance measurement of the train at the curve based on machine vision is proposed. In this method, monocular camera is used for track image acquisition, OpenCV algorithm is used to process and analyze the acquired images, and neural network method is used to fit the track line of curved rail, realizing the dynamic extraction of track feature points. The distance formula between trains can be calculated and optimized by building a mathematical model. The experimental results show that the overall error rate of the testing system is less than 9.11% when the duration interval is 40~50 ms. The method for the spacing measurement can be integrated together with other information in the collected images for the information fusion and referred as an important condition in the rail system for a train running. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automobile Technology is the property of Automobile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Space-Integrated-Ground Information Networks is the property of Beijing Xintong Media Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problems of real-time monitoring of the airbag shapes of a space airship, three-dimensional (3D) deformation reconstruction method of airbag skins was proposed based on temperature self-decoupling multi-core optical fiber sensor. According to the 3D shape characteristics of the airship airbags, the layout of the multi-core optical fiber sensors were designed, sensing structure of multi-core optical fiber was combined with the Frenet-Serret equation to establish a 3D deformation reconstruction algorithm of the airship airbags with temperature self-decoupling function. Using flexible composite skins of the airship airbag as the test subjects, the 3D deform multi-core optical fiber reconstruction test system of the airship airbag was designed and integrated. The test analyzed the 3D deformation reconstruction accuracy of the multi-core optical fiber se: under the temperature change environments and the surface of airship airbag skins under diff bending degrees, and verified the effectiveness of the method. The research results show that method of multi-core optical fiber sensor with temperature self-decoupling may accurately recons the deformation of the airship airbag skins in a large range of temperature environment, and the age value of the reconstruction errors of the 3D surface of the airship airbag skins is less than 1.5%. The real-time monitoring of shapes has application prospects. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to ensure the reliability and safety of high-speed railway train control on-board equipment, it is necessary to carry out full and comprehensive testing and verification. Aiming at the problems of inferior expandability, inferior reusability of resources and complicated software design for train control simulation test system, this paper puts forward the scheme of design of the business middle platform based on domain-driven design and microservice on the foundation of the deep research on domain-driven theory and the characteristics of microservice. Based on the deep discussion over the systematical architecture with the systematical domain-driven model and combined with the business features and systematical functions of the high-speed railway train control simulation test system, integral business middle platform is designed from the perspectives of modeling in business domain, middle platform plan, service identification and design, and service realization. Finally, the application and analysis of the typical business cases based on the practical construction of the high-speed train control simulation test system show that the system built on the basis of domain-driven and microservice has high expandability, high maintainability and high reusability. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wavelength Division Multiplexing (WDM) devices, as one of the core components of 5G fronthaul network, have developed rapidly in recent years. The fronthaul network has proposed new requirements for WDM devices, components and products. However, the technical requirements and test method standards of WDM devices for 5G fronthaul network are not dear. Through in-depth analysis of the problems encountered in the test of WDM devices, we propose a test method of 5G fronthaul WDM devices, and build the corresponding test system, which is compared with the manual test method. The results show that the proposed test method has 10 times more efficient than manual test method with good consistency. [ABSTRACT FROM AUTHOR]

Aiming at the vibration reduction problems of pipeline systems under high temperature, a high temperature mechanics model of the metal rubber coated damping structure of the pipe-lines was established by equivalent linearization method. The model was used for analyzing the stiffness and response amplitude of metal rubber treated with different temperatures. The thermal-vibration joint test system of the pipelines was set up firstly. Then the damping performance of the coated damping structure of the pipelines was verified with different ambient temperatures and metal rubber densities, where the insertion loss was taken as the evaluation index. The results show that reducing he density of metal rubber may effectively increase the vibration attenuation effectiveness of the pipelines. At the same time, the effect of the ambient temperature on the metal rubber coated damping structure is negligible, indicating that the coated damping structure may work well in a high temperature environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the difficult and inaccurate testing of the machine tool spindle bearing preloads, an online monitoring method was proposed herein based on FBG sensor. Firstly, the thermal analysis model of the spindle unit was established considering the heat generated by the spinning friction of the rolling elements, the contact thermal resistance between the inner/outer ring of the bearings and the spindle/housing. Secondly, a thermally induced preload test system for the spindle bearings was built. Through simulation and experimental comparison, the temperature distribution and thermally induced preloads of the key components of the spindle unit were analyzed at different speeds. The results show that the temperature measured by FBG sensor and thermal sensor is consistent with the simulation temperature prediction, which verifies the accuracy and reliability of the method proposed. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the chip shapes and the influence law of drilling parameters and vibration parameters on drilling forces (thrust force and torque) during low frequency vibration drilling of TC4 titanium alloy. Based on a self-developed low-frequency vibrating tool holder, low-frequency vibration drilling tests of titanium alloy were carried out by single factor method and orthogonal test method respectively. Chip shapes and drilling forces under different drilling conditions were analyzed. Empirical formulas of thrust force and torque were established. The influence factors of drilling forces were analyzed by visual analyses and variance analyses. Results show that when TC4 titanium alloy is drilled in low frequency vibration, the ratio of amplitude and feed is close to the critical chip breaking value of 0.81, the chip breaking is reliable, and the chip discharging is smooth. The instantaneous drilling force of low frequency vibration presents regular sine wave, and the dynamic component of drilling force is much larger than the ordinary drilling. The thrust force and torque mean may be reduced by 10%~15% and 15%~20% respectively than that of the ordinary drilling. The feed rate has the most significant influences on the drilling forces, the amplitude takes second place, the drilling speed has the least influence. The established vibration drilling experience model error is kept within 10%, which may accurately predict the drilling forces within the selected parameters of the test systems. [ABSTRACT FROM AUTHOR]

The fiction and wear and longlife lubrication performances of space lubricants in space environments were investigated. The hydrocarbon lubricant RP4752 was used as the research object, and the vacuum spiral orbit tribometer (SOT) and siding friction test system were used to test the lubricating oils. Nominal lubrication life, wear spot diameter and siding friction coefficient were combined with scanning electron microscopy and X-ray energy dispersive spectrometer for microscopic analysis. The results show that RP4752 has a small siding fiction factor and a long wear life in a vacuum environments, and has good vacuum boundary lubrication performance. The lubricating infrared transmittance has no significant change in 14~16.25µm band. In the vacuum life verification tests, the numbers of rotations of two scanning motors lubricated with RP4752 reach 3.02 X 108, which meets the 8-year on-orbit operating life requirements of the moving mechanisms. The results form a compassion relationship with a nominal life of 1 615 rotations by SOT tests, which provides a test basis for the selection of lubricants for other space motion mechanisms and longlife lubrication design. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accurate measurement of rock cohesion c and internal friction angle φ( hereinafter referred to as the c-φ parameter) is the basis of optimizing the design of underground engineering support and information construction. The traditional indoor test method has the characteristics of cumbersome testing steps, long cycle and high cost, and cannot carry out in-situ measurement. Therefore, it is necessary to develop an accurate and fast on-site testing method for rock c-φ. Digital drilling testing technology provides a new way for accurate and fast prediction of rock c-φ in-situ, and the key is to establish the quantitative relationship between drilling parameters and rock c-φ. According to the fracture characteristics of rock cutting, a rock cutting mechanics model without prior assumption of failure surface is proposed. This model makes up for the deficiency of the existing rock cutting mechanics model that assumes the failure surface as a plane and thus differs from the actual characteristics of the failure surface in rock cutting. The ultimate cutting force is deduced on the basis of the slip-line theory. Based on this, the relationship between drilling parameters( DP) and c-φ parameter( hereinafter referred to as the DP-cφ relationship) is established. In this paper, the digital drilling test is carried out by using the self-developed digital drilling test system. Compared with the results of theoretical analysis and laboratory test, the average difference is 8. 44%, which verifies the rationality and correctness of the rock cutting mechanics model and the DP-cφ relationship. Therefore, a digital drilling measurement method for the rock c-φ parameter is proposed. Compared with the results of this method and traditional triaxial method through laboratory tests, the average difference rate of cohesion and internal friction angle obtained by the two methods are less than 10%, which proves the feasibility and effectiveness of the digital drilling method proposed in this paper. The method is convenient and fast, and can realize in-situ measurement of the c-φ parameter of the rock mass in the field. [ABSTRACT FROM AUTHOR]

In order to study the mechanical performance of whorl steel anchor under static and dynamic loads, the selfdeveloped static and dynamic loading test system was used to carry out a static tensile experiment and dynamic impact experiment under the prestress loading or non-prestress load on the equal strength and non-equal strength rebar bolts. The results show that under static loading, equal strength and non-equal strength rebar bolts all have experienced four stages: "linear elastic deformation-yielding platform-strengthening stage-radial shrinkage failure"; under impact loading, the yielding stage of anchor bolt can be divided into transient yield and steady yield. The peak load of transient yield is higher than that of steady yield load, and the corresponding yield elongation of bolt decreases; with the increase of bolt diameter, the yield elongation increases under impact condition.Compared with the equal strength anchor bolts,non-equal strength bolts have good adaptability under impact loading.When the impact energy is less than 9 kJ, the an-chor rod body not only can withstand multiple impact disturbances,but also can ensure enough strength after impact. Whereas, when the impact energy is higher than 9 kJ, the energy dissipation capability of the bolt decreases significantly. No matter from the dynamic axial force-displacement curve or the peak load and elongation of the bolt, the prestress has no obvious influence on the dynamic response characteristics of the bolt under the impact load, but it is necessary to improve the loading level of the prestress for anti-impact bolt support. [ABSTRACT FROM AUTHOR]

In terms of compound dynamic disaster in depth high-gas mine, in order to investigate the influence rule of coal and rock mechanical behavior by gas pressure, a set of experimental equipment for testing coal samples deformation and failure under uniaxial compression condition of coal and rock containing gas was developed with the RMT- 150C rock mechanics test system as a carrier, and then, constituted a gassy coal uniaxial compression experiment system with XL2101C SPC static resistance strain gauge. Outburst-proneness index determination tests were conducted on this system. The results showed that ① the volume-expanding phenomena of coal samples occur with the increase of gas pressure during the process of gas filling and adsorption. The volume change of coal samples is divided into two stages: the accelerated deformation stage and the gentle stage;② with the increase of gas pressure from 0 MPa to 2 MPa, the dynamic failure time of coal samples decreases by 547. 64%,the elastic energy index, impacting energy index and compressive strength of coal samples decrease 85. 29%,96. 24% and 58. 78% respectively. The comprehendsive evaluation result is a decrease in impact tendency. [ABSTRACT FROM AUTHOR]