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Silicone rubber composite insulators (SiR) for electric power will encounter lightning strike or fire during operation, and SiR will fail due to complex changes such as expansion and cracking after pyrolysis at different temperatures. However, the pyrolysis performance of SiR and the microscopic reasons for these changes are still unclear. In this paper, the thermal degradation of SiR at different temperatures was discussed, and the relationship between pyrolysis temperature and the structure, mechanical properties and surface hydrophobicity of SiR was explored. The thermal stability of SiR was studied by synchronous thermal analyzer. The results show that the microstructure of SiR changes significantly with the increase of pyrolysis temperature. Due to the release of pyrolysis gas and molecular crosslinking in SiR, a large number of pores are produced on the surface of SiR, and the crosslinking degree and tensile properties of silicone rubber decrease. When the pyrolysis temperature is above 300 °C, the mechanical properties and C--H bonds of the pyrolyzed SiR decrease obviously. [ABSTRACT FROM AUTHOR]

Copyright of Automotive Engineer (1674-6546) is the property of Auto Engineering 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 Automotive Engineer (1674-6546) is the property of Auto Engineering 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 Journal of Guangxi Normal University - Natural Science Edition is the property of Gai Kan Bian Wei Hui 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.)

This paper searches and combs the achievements of grey system theory in the past nearly 40 years based on databases of China national knowledge internet (CNKI) and ISI Web of Science. More than 227 thousands literatures were found by inputting 10 phrases such as grey system‑grey number and sequence operator etc. in CNKI. After entering the 21st century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year, and more than 15 thousands papers have been included per year since 2014. The grey system method and model are widely used in natural science fields such as physics, chemistry, and biology, as well as engineering technology fields such as transportation, electric power and machinery, and a large number of valuable results have been achieved. From the large number of documents applying the grey system method and model, which are published by the project team undertaking important national science and technology plans and the double first‑class universities in China, it can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development, and high-level talent training. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience 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 Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural 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 recovery and utilization of train electric braking feedback energy, this paper analyzes the train operation characteristics, and focuses on the relationship between the train operation process and the voltage fluctuation of the traction network. Combined with the dynamic mismatch between the power supply of the traction substation and the electric power of the train, the scheme of the on-board braking energy recovery and utilization system is adopted, and a supercapacitor charging and discharging control strategy based on the dynamic change of the electric power of the train is proposed. The scheme is mainly composed of super capacitor series-parallel energy storage unit and bidirectional DC-DC converter. In this paper, MATLAB is used for modeling and simulation analysis. The simulation results show that the control strategy can effectively recover and utilize the train braking energy while suppressing the voltage fluctuation of the traction network, which provides an effective solution for the recovery and utilization of the train braking energy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal 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 Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of 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 Construction Technology is the property of Railway Construction 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 Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of 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.)

The secondary energy on board has been gradually replaced by electrical power in more electric aircraft, effectively improving the fuel economy, reliability and maintainability of the aircraft, and has become an important direction of the aviation technology. As the core of the secondary energy system on board, the power system plays a key supporting role in the development of more electric aircraft. The innovative development of the power system and related technologies are the necessary basis to realize the improvement and global optimization of the aircraft comprehensive performance. Based on the concepts and characteristics of more electric aircraft, this paper analyzes and compares the electric power system architecture of three typical more electric aircraft, summarizes the key technologies supporting the development of more electric aircraft electric power system, and discusses the development trend of high voltage, direct current and intelligent more electric aircraft electric power system in the future. [ABSTRACT FROM AUTHOR]

Pure electric vehicles are the hotspot of current research and development, and the power train parameter matching design is the key technology of pure electric vehicles. In this paper, a power train parameter matching design is applied to a pure electric vehicle. According to the performance requirements of the vehicle and the dynamic principle, the design and matching calculation of the vehicle’s motor, battery, main reduction ratio and other dynamic parameters are carried out. The AVL CRUISE software is used to establish the vehicle model of the target vehicle, and the braking energy recovery model is built with Simulink. Combined with two typical working conditions, NEDC and FTP75, the joint simulation is carried out. The simulation results show that the power train parameters and braking energy recovery control strategy designed in this paper can meet the performance requirements of the target vehicle, which can effectively improve the dynamic performance of the vehicle, increase the driving range of the vehicle and improve the battery life. The research content of this paper can provide reference for the research of design and control strategy of pure electric vehicle power train. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering 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 Clean Coal Technology is the property of Clean Coal 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 Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications 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 Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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 Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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 Clean Coal Technology is the property of Clean Coal 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.)

This paper introduces the design and implementation process of electric power safety experiment training system based on 3D virtual simulation technology, and expounds the whole process of power safety experiment training system from system requirement and function design to system design and system realization. The system is realized by using ASP. NET technology and unity3D technology effectively. Management, student management, test question management, task management, peformance management, power safety data management and other core functions can be completed by the system. The examination system makes use of unity3D technology which applies 3D scene and WEB design theory. The electric power workers can simulate and manipulate the whole maintenance process through computer so as to improve the employees of electric power construction operation skills. [ABSTRACT FROM AUTHOR]

Silo is widely used in grain, logistics, electric power, metallurgy and other industries. Therefore, the reasonable design of silo structure is the key. China is a large country of grain production, with application of the modern granary environmental protection, energy saving, green and other concepts, the cylinder wall is higher, and larger diameter, occupies less land, saves resources of the silo and is more and more in line with the future development trend of granary, and with the trend of rapid development around the world. With the increasing height and diameter of silo, the problem of failure in silo discharging is becoming more prominent. The dynamic lateral pressure of grain silo during discharging is the major cause of silo failure. In this paper, based on the indoor grain silo discharging model test, the whole process of the silo center emptying was recorded with high-speed camera, the flow pattern of grain was analyzed with image processing technology, and the dynamic pressure generated during the discharge process was measured. Based on this test, the particle flow code (PFC3D) was used to carry out numerical simulation to track the movement of specific particles in the test. By comparing the results of the experiment and the numerical simulation, the mechanism of overpressure in the discharge of the silo was explored. Through this study, in the process of discharging in the center, there were two kinds of flow states, the mass flow and the tubular flow. At the beginning of the discharge, the stored material flowed as mass flow. After a period of time, the upper part of the material flowed as mass flow, the bottom of the storage was a tubular flow, and the mass flow was in the high diameter ratio close to 1 of the height position to convert to tubular flow. When the discharging height reached 1.1m, the stored material flowed in tubular flow until the discharge was completed. Both the dynamic lateral pressure and the static lateral pressure increased with the depth of the measuring point, and the dynamic lateral pressure was greater than the static lateral pressure. At the beginning of the discharge, the dynamic lateral pressure measured by the silo suddenly increased, and then the dynamic lateral pressure value decreased with the continuous reduction of the storage height. The overpressure coefficient measured by the three groups of sensors was larger in the height range of the high diameter ratio close to 1, and the overpressure phenomenon was obvious. In the process of silo discharging, the speed of tubular flow of the bottom stored material was greater than the speed of the mass flow of the middle and upper stored material. There was a pressure arch at the junction of the two flow states, and the existence of the pressurized arch hindered the normal flow of the upper stored material, which led to the self-weight of the stored material and the additional force caused by the change of momentum was almost entirely by the arch, resulting in the increase of the dynamic lateral pressure and a significant overpressure phenomenon. [ABSTRACT FROM AUTHOR]

The unit energy consumption of vaporization-transportation is not only an important operation indicator, but also the basis of energy-saving study at LNG terminal. This paper addressed the issue in the following process： Firstly, the process and equipment involved was introduced; subsequently, the electric power of low-pressure pump, high-pressure pump, seawater pump and other power consumption equipments were calculated, as well as the gas-consumption of torch eve-burning lamps and SCV. After that, the unit energy consumption was obtained as 4. 625 kgce/t if 1 t natural gas was vaporized and transported in the minimum transportation conditions with ORV as vaporizer in summer, and the value shifted to be 25. 83 kgce/t in the maximum transportation conditions with SCV as vaporizer in winter. It was found in the comparison that the unit energy consumption of running SCV was much higher than the running ORV. Finally, the relationship between the natural gas flow of transportation and the unit energy consumption was determined by computer program, as showing in the curve. From the curve, it was found that the minimum unit energy consumption about vaporization-transportation was 1. 946 kgce/t，while the corresponding natural gas flow of transportation was 690 t/h. Besides, the unit energy consumption decreased while natural gas flow of transportation increased， but the unit energy consumption would tncrease rapidly reversely at the moment of adding running equipments. [ABSTRACT FROM AUTHOR]

To solve the problem of unstable operation caused by capacity limitation of microgrid storage system, this paper presents an improved microgrid cooperative control strategy, of which the structure is double-layer of cooperative control, that is the primary control is the battery energy storage system and the secondary control is a microgrid management system (MMS). The primary control ensures that the frequency of the microgrid is within the acceptable range, while the secondary control ensures the largest spare capacity in the microgrid. To accurately describe the different types of distributed power of the prime mover to affect the microgrid system, by using detailed micro-source model, a microgrid simulation system is established and simulated. The simulation results show that the cooperative control strategy has a good dynamic performance, and ensures the quality of power supply requirements. Therefore the cooperative control strategy of microgrid has a better application prospects. [ABSTRACT FROM AUTHOR]

The wave rotor is a self-cooled dynamic pressure exchange machine that can improve the engine performance and fit diversified course. In this paper, the thermo-cycle analysis mode of a wave-rotor-topped small gas turbine engines is established. When the compressor, the turbine pressure ratio, and the turbine inlet temperature vary in the thermodynamic calculation according to the anticipated design objectives in the five considered cases, the influence of wave rotor on the performance of small gas turbine engines is investigated. The variable laws of wave rotor-applied combustor work condition is discussed. The best performance is obtained in the topped engine operates with the same compressor pres- sure ratio, inlet temperature and physical compressor like that of the baseline engine. The prime performance optimized region and the combustor work condition of the wave-rotor-topped small gas turbine engines are obtained. [ABSTRACT FROM AUTHOR]

Aiming at the problem of low accuracy of traditional prediction methods of anti-electricity stealing, a prediction method of anti-electricity stealing based on big data of electric power was proposed. This method firstly constructed samples of electricity stealing data according to abnormal rules, and introduced the growth rate of line loss rate constraint conditions. Then it used four machine learning classification algorithms to build a prediction model on the voltage, current and power factor data sets respectively, combined the users with abnormal data output and users with abnormal line loss to output a list of users suspected of stealing electricity. Experimental results showed that the prediction accuracy of the method was satisfactory, and it was efficient and feasible in identifying users suspected of stealing electricity. [ABSTRACT FROM AUTHOR]