Research Progress of On-line Monitoring Technology for Electromagnetic Environment of Power Transmission and Transformation Projects

Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home and abroad were introduced.Moreover,the problems existing in the on-line monitoring of electromagnetic environment were expounded,and the development prospect was forecasted.

Emerging Technologies of Future Multimedia Coding, Analysis and Transmission

Three years ago,ZTE Communications published a special issue called Emerging Technologies of Multimedia Coding,Analysis and Transmission.Over the past three years,great advances have been made in multimedia.The purpose of this special issue is to report on the progress and

Study on Key 750-kV Transmission Technologies

According to the special environment conditions and characteristics of high altitude in Northwest China, the study on key technologies of 750-kV transmission and substation projects has gained fruitful results which are imperative not only to the construction of 750-kV transmission demonstrative project first in China, but also has laid a solid foundation for future UHV transmission constructions.

Manufacturing Development Emphases on Power Generation and Transmission Apparatus in 11th Five-Year Plan Period and Prospect to the Year 2020

Based on predictions on Chinese power development in the coming 20 years, this paper introduces the emphases and key technologies in power sources and power network construction, and puts for ward the major tasks and technological orientation for machinery manufacturers to supply qualified equipment to China power industry.

Adaptive Clutch Engaging Process Control for Automatic Mechanical Transmission

Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly. Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results.

Transmission of the Chromosome 1R in Winter Wheat Germplasm Aimengniu and Its Derivatives Revealed by Molecular Markers

In order to clarify the transmission of the rye chromosome 1R in winter wheat germplasm Aimengniu and its derivatives, 17 derivatives and 7 types of Aimengniu were examined through molecular-marker technology. The results showed that the chromosome arm 1RS of Neuzucht was transmitted to 5 of the 7 types of Aimengniu, i.e., Aimengniu Ⅱ and Aimengniu Ⅳ-Aimengniu VII, no segment of t RS was identified in Aimengniu Ⅰ or Aimengniu Ⅲ. As for the 17 derivatives, the 1RS chromosome arm of Aimengniu was transmitted to 11 derivatives, part segments of 1RS were found in 1 derivative, while no segment was found in the remaining 5 ones. The results provided the evidence that molecular-marker technology was an efficient approach and suitable for analysis of the transmission of chromosome 1R.

Technology of structure damage monitoring based on multi-agent

The health monitoring for large-scale structures need to resolve a large number of difficulties,such as the data transmission and distributing information handling.To solve these problems,the technology of multi-agent is a good candidate to be used in the field of structural health monitoring.A structural health monitoring system architecture based on multi-agent technology is proposed.The measurement system for aircraft airfoil is designed with FBG,strain gage,and corresponding signal processing circuit.The experiment to determine the location of the concentrate loading on the structure is carried on with the system combined with technologies of pattern recognition and multi-agent.The results show that the system can locate the concentrate loading of the aircraft airfoil at the accuracy of 91.2%.

Controlling the light wavefront through a scattering medium based on direct digital frequency synthesis technology

Phase modulation is a crucial step when the frequency-based wavefront optimization technique is exploited to measure the optical transmission matrix(TM) of a scattering medium. We report a simple but powerful method, direct digital frequency synthesis(DDS) technology to modulate the phase front of the laser and measure the TM. By judiciously modulating the phase front of a He–Ne laser beam, we experimentally generate a high quality focus at any targeted location through a 2 mm thick 120 grit ground glass diffuser, which is commercially used in laser display and laser holographic display for improving brightness uniformity and reducing speckle. The signal to noise ratio(SNR) of the clear round focus is 50 and the size is about 44 μm. Our study will open up new avenues for enhancing light energy delivery to the optical engine in laser TV to lower the power consumption, phase compensation to reduce the speckle noise, and controlling the lasing threshold in random lasers.

Electromagnetic Transmission Characteristics of Y-Shaped and Y-Ring-Shaped Frequency Selective Fabrics

Asymmetrical Y-shaped and Y-ring-shaped frequency selective fabrics(FSFs) were proposed in this paper. They were prepared by computer engraving technology and tested in the anechoic chamber by using the free-space method. The test results of representative samples show that the resonance frequencies and the resonance peak or valley values in two polarization modes are not completely identical but the differentials are small, indicating that the influences of polarization modes are not significant. The transmission coefficient curves of Y-shaped and Y-ring-shaped FSFs with various size parameters are obviously different. For instance, as the unit size D increases by 4.0 mm, the resonance frequencies of patch FSFs decrease by 1.92 GHz and the resonance valleys increase by 12.32 dB. Different size parameters have dissimilar effects on the transmission characteristics and the corresponding influence laws should be analyzed concretely. The work could provide reference for the structural design and characteristics analysis of other FSFs.

Research on Fuzzy Control for Automatic Transmission of Tracked Vehicles

A principle of fuzzy control for tracked vehicles is proposed to make its automatic transmission system be able to adapt complex running conditions, and a model of its power train is established to be used in simulation. Based on the fuzzy control method, a fuzzy shift control system composed of a basic shift strategy and a fuzzy modification module is developed to improve the dynamic characteristics and cross-country maneuverability. Simulation results show that the fuzzy shift strategy can improve the shift quality under manifold driving conditions and avoid cycled shift effectively.Therefore, the proposed fuzzy shift strategies are proved to be feasible and practicable.

An overview on research developments of toroidal continuously variable transmissions

As environmental protection agencies enact new regulations for automotive fuel economy and emission, the toroidal continuously variable transmissions (CVTs) keep on contribute to the advent of system technologies for better fuel consumption of automobiles with internal combustion engines (ICE). Toroidal CVTs use infinitely adjustable drive ratios instead of stepped gears to achieve optimal performance. Toroidal CVTs are one of the earliest patents to the automotive world but their torque capacities and reliability have limitations in the past. New developments and implementations in the control strategies, and several key technologies have led to development of more robust toroidal CVTs, which enables more extensive automotive application of toroidal CTVs. This paper concerns with the current development, upcoming and progress set in the context of the past development and the traditional problems associated with toroidal CVTs.

Application of Model-Based Data Transmission Techniques to Gravitational Model Data

The transmission of scientific data over long distances is required to enable interplanetary science expeditions. Current approaches include transmitting all collected data or transmitting low resolution data to enable ground controller review and selection of data for transmission. Model-based data transmission (MBDT) seeks to increase the amount of knowledge conveyed per unit of data transmitted by comparing high-resolution data collected in situ to a pre-existing (or potentially co-transmitted) model. This paper describes the application of MBDT to gravitational data and characterizes its utility and performance. This is performed by applying the MBDT technique to a selection of gravitational data previously collected for the Earth and comparing the transmission requirements to the level required for raw data transmis-sion and non-application-aware compression. Levels of transmission reduction up to 31.8% (without the use maximum-error-thresholding) and up to 97.17% (with the use of maximum-error-thresholding) resulted. These levels significantly exceed what is possible with non-application-aware compression.

Will Market-Oriented Reforms Propel Technology Progress?Empirical Evidence from China’s High-Tech Sectors

This paper aims to explore the effects of market-oriented reforms on industrial technology progress.Based on a theoretical analysis,we performed an empirical study with a marketization index and panel data of high-tech sectors in China.We found that market-oriented reforms had significantly propelled technology progress in China’s high-tech sectors,and the effects became more evident after China’s WTO entry.Market-oriented reforms induced technology progress by increasing capital allocation efficiency,R&D input,and technology diffusion.Among various aspects of market-oriented reforms,the institutional environment exerted the most significant effects,followed by the economy’s non-state sector,product market development,and factor market development;the government-market relationship index influenced technology’s progress the least.The effects are heterogeneous across sectors with different technology attributes and more significant for technology-intensive sectors.Our findings offer policy implications for China’s ongoing market-oriented reforms and policy design for technology progress in high-tech sectors.

Key Technical Research on Power Electronics and Information Transmission System

Power electronics is a new technology of power transmission and control.Compared with the traditional power transmission,non-contact power transmission has the advantages of low wear rate,safety,reliability,convenience and flexibility.In this way,it avoids the problems of friction,wear,aging and so on in the traditional power supply mode,saves a lot of wires,makes up for the shortcomings of the traditional power transmission mode,and has a wider application range.Therefore,it is of great practical significance to study the key technology of power electronic information transmission for promoting the intelligent development of power transmission in China.

The molecular mechanism of meridian qi sensory transmission by heat-sensitive moxibustion in the treatment of cerebral infarction

Background:To explore the potential mechanism of thermal moxibustion in the treatment of i schemic strok e by using the method of network pharmacology and to partially explain the mechanism of acupoint meridian qi sense transmission.Methods:In this project,a training set was formed by researching the intersection of the reported components of M ugwort leaves that entered the blood after combustion and obtained the targets of heat-sensitive moxibustion meridian qi sensing and thermal effect by querying the literature.The Encyclopedia of Tr ad itional Chinese Medicine is used to search and screen the highly active chemical constituents of Artemisia argyi to predict potential targets;search i schemic strok e-related targets through GeneCards,O nline Mendelian Inheritance in Man,Drugbank databases.Gene Oncology functional analysis and Kyoto Encyclopedia of Genes and Genomes signaling pathway enrichment analysis were performed on the potential targets of the blood components of Artemisia argyi and molecular docking simulated the binding activity of key candidate active components and core genes.Results:192 ischemic stroke disease targets with r elevance score greater than 10 were screened out for analysis.Through the database Encyclopedia of Tr ad itional Chinese Medicine query of the action targets(243)of Mugwort leaves and the intersection of heat-sensitive moxibustion effect targets and ischemic stroke-related targets,a Venn diagram was drawn and a total of 17 were obtained.Finally,the effective components of Mugwort leaves into the blood were screened out.Five main volatile components were molecularly docked with 17 targets and 9 targets of acupoint meridian gas sensing/thermal effect.The docking results showed that the main volatile components showed good affinities for binding to key targets,respectively.Conclusion:Using the characteristics of“multi-component-multi-target-multi-pathway”of traditional Chinese medicine,the potential mechanism of action of Artemisia argyi in the treatment of i schemic strok e is explored,which provides a certain basis for the follow-up scientific research and clinical application of Artemisia argyi in the treatment of IS.

Design of 1000-kV AC Single-Circuit Overhead Transmission Line

The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage.There are no guidelines or standards available for the design of 1 000-kV overhead transmission line in China.Study on key technologies and design schemes shall be carried out to ascertain the technical principles and construction standards for project construction,which are presented in this paper based on the Southeast Shanxi-Nanyang-Jingmen test and demonstration transmission line.A comparison and analysis of technical data and economic indices between UHV line and other lines are also described.

TLJ型土工离心机数据采集系统更新升级

长安大学TLJ-3土工离心机自2004年建成投入使用以来,已经运行18 a,为该系列运行时间最长的土工离心机。由于20世纪初电子设备集成性较低等原因,早期的TLJ型离心机数据采集系统逐渐无法满足现有试验数据的高精度、大数据量吞吐等采集需求。基于无线传输技术消除了电滑环接触电阻变化对数据传输影响的问题,采用光纤集成多个传感器使得传感器小型化,采用非接触式位移场扫描实现地表的全断面监测,基于Open CV图像拼接技术解决了图像畸变的问题。升级改造后的TLJ-3土工离心机已服务于若干研究项目,性能良好。

能源技术进步与区域专业化——特高压输电工程的视角

基于2003—2020年中国285个地级市数据,以特高压输电工程为切入点,研究能源技术进步对区域专业化的影响及作用机制。结果显示:以特高压输电技术为代表的能源技术进步显著提升了区域专业化水平,具体而言,较没有特高压输电项目城市,配备特高压输电工程城市的专业化水平提升约1.09%,且该效应在中小城市、资源丰富城市和内陆地区更强;在考虑样本选择偏差、基期分工水平、调整指标测度、剔除极端值并进行安慰剂检验和倾向得分匹配后,该结果依然稳健;进一步的机制分析表明,特高压建设所表征的能源技术进步通过激发资源禀赋的比较优势、生产的集聚效应来促进地区专业化。继续扩大特高压输电规模,合理实施区域专业化,互通有无、取长补短,对促进区域协调发展具有重要意义。

机器人灵巧手研究综述

机器人灵巧手可以模仿人类动作,完成复杂场景下的多种任务。机器人灵巧手的研究是开发智能人形机器人的关键技术之一。以机器人灵巧手的研究历程为核心,阐述了多指灵巧手的研究现状,分析了灵巧手的演化过程和研究进展。从自由度数目、驱动方式、机械传动方式和传感技术等方面探讨了灵巧手分类和特征,展望了灵巧手未来的发展趋势。