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The effects of population aging on industrial structure upgrading:Empirical analysis of provincial and threshold characteristics in China
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作者 Mao Hu Linyu Xiao Hong Qiu 《Chinese Journal of Population,Resources and Environment》 2024年第3期356-366,共11页
Global population aging trends are intensifying,presenting multifaceted economic and social challenges for countries worldwide.As the world’s largest developing country,China has entered a phase of extreme demographi... Global population aging trends are intensifying,presenting multifaceted economic and social challenges for countries worldwide.As the world’s largest developing country,China has entered a phase of extreme demographic aging,posing significant questions about its impact on the ongoing upgrading of industrial structures.How does this demographic shift influence the upgrading of industrial structures,and does technological innovation mitigate or exacerbate this impact?The empirical results indicate that population aging impedes upgrading the industrial structure,while technological innovation positively affects the relationship between the two.Moreover,using technological innovation as a threshold variable,the impact of population aging on industrial structure upgrading evolves in a“gradient”manner from“impediment”to“insignificant”to“promotion”as the technological innovation levels increase.These findings offer practical guidance for tailoring industrial policies to different stages of technological advancement. 展开更多
关键词 Population aging Technological innovation level Industrial structure upgrading Panel threshold models Instrumental variable method
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Study of Electro-Optical Measuring System for Measuring the Swaying of Rocket Launcher and Artillery Systems 被引量:1
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作者 李洋 闫钰锋 +1 位作者 蔡立娟 刘振波 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第4期247-249,共3页
A scheme is proposed,of that the axis of directional barrel is simulated by a laser beam and an electro-optical axial angle encoder is using to measure the swaying of rocket launcher or artillery. The measuring princi... A scheme is proposed,of that the axis of directional barrel is simulated by a laser beam and an electro-optical axial angle encoder is using to measure the swaying of rocket launcher or artillery. The measuring principle is stated,and an electro-optical measuring system is designed,including automatic force-applying device,angle-measurement device and photodetecting screen. The measurement accuracy of the system is analyzed. The measuring error of system is less then 17.3″(0.08 mil). 展开更多
关键词 电子光学测量系统 导弹 测量方法 发射轨迹
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Privacy Preservation of Smart Meters Based on Identity Authentication
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作者 Hongbo Hu Xin Zhao +3 位作者 Yalian Wu Mengbiao Huang Ziqi Zhu Qingyu Yang 《Energy and Power Engineering》 2020年第4期53-62,共10页
Smart meters provide a lot of convenience for both power supply and consumption. Due to the frequent transmission of information, it brings great challenges to the privacy preservation of the user’s household power c... Smart meters provide a lot of convenience for both power supply and consumption. Due to the frequent transmission of information, it brings great challenges to the privacy preservation of the user’s household power consumption data in the smart grid. In order to achieve the anonymity of smart meters. A smart meter privacy preservation scheme based on identity authentication is proposed. The third-party certification authority is introduced in this scheme;it issues pseudonym certificates to realize the identity privacy preservation of smart meters. The masking technology with the Advanced Encryption Standard algorithm is used for data aggregation. The results show that our scheme reduces the computational cost and the communication overhead. 展开更多
关键词 Smart METER IDENTITY AUtheNTICATION PRIVACY PRESERVATION MASKING Technology
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Yatai Meters & Instruments to Occupy Domestic and International Markets
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《China's Foreign Trade》 2002年第1期25-25,共1页
Shanghai Yatai Meters & Instruments Co. Ltd. was set up in 1991. It is engaged in research and development of meters and instruments for industrial duration measurement and control system. It is a new hi-tech ente... Shanghai Yatai Meters & Instruments Co. Ltd. was set up in 1991. It is engaged in research and development of meters and instruments for industrial duration measurement and control system. It is a new hi-tech enterprise worthy of the name. Recently it has completed the reform of holdings system. 展开更多
关键词 CO CO 口口 Yatai meters instruments to Occupy Domestic and International Markets ISO
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Investigation into the Independent Metering Control Performance of a Twin Spools Valve with Switching Technology-controlled Pilot Stage 被引量:6
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作者 Qi Zhong Huiming Bao +3 位作者 Yanbiao Li Haocen Hong Bin Zhang Huayong Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期226-242,共17页
In hydraulic area,independent metering control(IMC)technology is an effective approach to improve system efficiency and control flexibility.In addition,digital hydraulic technology(DHT)has been verified as a reasonabl... In hydraulic area,independent metering control(IMC)technology is an effective approach to improve system efficiency and control flexibility.In addition,digital hydraulic technology(DHT)has been verified as a reasonable method to optimize system dynamic performance.Integrating these two technologies into one component can combine their advantages together.However,few works focused on it.In this paper,a twin spools valve with switching technologycontrolled pilot stage(TSVSP)is presented,which applied DHT into its pilot stage while appending IMC into its main stage.Based on this prototype valve,a series of numerical and experiment analysis of its IMC performance with both simulated load and excavator boom cylinder are carried out.Results showed fast and robust performance of pressure and flow compound control with acceptable fluctuation phenomenon caused by switching technology.Rising time of flow response in excavator cylinder can be controlled within 200 ms,meanwhile,the recovery time of rod chamber pressure under suddenly changed condition is optimized within 250 ms.IMC system based on TSVSP can improve both dynamic performance and robust characteristics of the target actuator so it is practical in valve-cylinder system and can be applied in mobile machineries. 展开更多
关键词 High speed on/off valve(HSV) Digital hydraulic technology(DHT) Switching pilot control Twin spools valve Independent metering control(IMC)
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An overview on observational instruments and measuring methods for dewfall 被引量:1
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作者 Qiang Zhang XiaoCui Hao +2 位作者 XiaoMei Wen Sheng Wang Jian Zeng 《Research in Cold and Arid Regions》 2011年第1期78-85,共8页
This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land sur... This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated. 展开更多
关键词 dewfall measuring methods observational instrument exploitation and utilization technology
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Study of Load Modeling Technology on Hardware-in-the-Loop Simulator of Gun Servo System
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作者 王红平 曹国华 +2 位作者 董彦良 赫赤 史德民 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第1期35-41,共7页
A hardware-in-the-loop (HWIL) simulator for gun servo system is described in this paper, and its load modeling technologies,such as road spectrum model,sea wave model are studied. The simulation results show that the ... A hardware-in-the-loop (HWIL) simulator for gun servo system is described in this paper, and its load modeling technologies,such as road spectrum model,sea wave model are studied. The simulation results show that the models can be used in HWIL and satisfy the requirements of hardware-in-the-loop simulator of gun servo system. 展开更多
关键词 technology of instrument and meter GUN load modeling road spectrum model sea wave model
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Editorial for the Special Issue on High-End Measuring Instruments
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作者 Jiubin Tan Kenneth Thomas Victor Grattan 《Engineering》 SCIE EI CAS 2022年第9期1-2,共2页
In recent years, two major challenges have arisen in the field of measurement and instrument technology. One is the redefinition of the seven basic units in the international system of units(Système Internationa... In recent years, two major challenges have arisen in the field of measurement and instrument technology. One is the redefinition of the seven basic units in the international system of units(Système International d’Unités or SI). The SI is now based on fundamental physical constants, with full implementation having occurred in 2019. 展开更多
关键词 technology. instrument arise
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Design and Evaluation of a Sensitive, Low Cost and Portable Millimeter Wave Survey Meter
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作者 Howard Bassen Negin Shahshahan +3 位作者 Amir Razjouyan Gonzalo Mendoza Mohammed Eslami Trent Robertson 《Open Journal of Antennas and Propagation》 2018年第3期25-35,共11页
We developed a small, hand-held, portable, low cost, millimeter wave (mmW) meter to detect and display the levels of emissions from L3 ProVision security scanners used in hundreds of airports for detection of contraba... We developed a small, hand-held, portable, low cost, millimeter wave (mmW) meter to detect and display the levels of emissions from L3 ProVision security scanners used in hundreds of airports for detection of contraband and weapons. The meter is intended to measure radiation emissions from this particular scanner and enable the user to enable periodic quality assurance measurements and to see if undesirably high levels were to occur. The non-engineering staff of the Transportation Security Administration (TSA) can use this meter to demonstrate safety of these scanners to passengers using this simple handheld instrument certified by the US Food Drug administration. This meter can assess human exposure levels during periodic quality assurance inspections, in a region where a person is being scanned, and demonstrate the lack of possible interference with body worn medical devices. It has receiving, signal processing, output display, and user control subsystems, and displays graphical and numerical information. The meter detects low level, pulses of mmW electromagnetic radiation (20 - 30 GHz with levels of 0.02 V/m to 0.15 V/m). It displays a single burst of five or more 10 μsec pulses. It detects levels as low as several thousand times below the maximum permissible levels prescribed by international human exposure safety standards. This compact system replaces the bulky and costly collection of large and costly instruments needed to perform the same measurements. 展开更多
关键词 Index TERMS MILLIMETER Wave Measurement Instrument METER EXPOSURE
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Communication Technology and Application of Seismic Precursor Network Instrument
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作者 Jianguo Wang Wei Wang +2 位作者 Huiqin Yao Xun Gao Mingdong Zhang 《Communications and Network》 2013年第1期1-4,共4页
In this paper, the communication technology of seismic precursor network instrument is introduced, including instruction format and returned information format of instrument login, status information acquisition, and ... In this paper, the communication technology of seismic precursor network instrument is introduced, including instruction format and returned information format of instrument login, status information acquisition, and current measured data acquisition. The remote monitoring alarm software is based on this technology, and also introduced that the structure of monitoring information table, abnormal alarm index, and monitoring strategy. The application of the software raises instrument running rate and observation data quality. 展开更多
关键词 NETWORK Instrument COMMUNICATION TECHNOLOGY REMOTE MONITORING ALARM
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Study on Relation between Dynamic Imbalance Degree and Product of Inertia
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作者 张心明 王黎明 +1 位作者 刘建河 周化文 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第1期65-68,共4页
Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of t... Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of the imbalance degree test for projectile body is the test of its product of inertia.A more precise calculation formula of dynamic imbalance degree is also given.The experiment results show that this method can not only reduce the cost of equipment,simplify the test procedures,save human resource,but also has more reliable test precision. 展开更多
关键词 子弹 动力平衡 旋转惯性 军事技术
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Proper Management of Standards Formulation for Marine Survey Instrument Products
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作者 Li Fang,Tang Hairong and Yang Zheling 《China Standardization》 2009年第6期38-44,共7页
The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should... The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should be interchangeable,so as to reduce product costs and reasonably economizethe use of energy and material resources.This paper intruduces the importance of formulating marine instrumentproduct standards,the present conditions and problems of marine product standards,and proposesrelated measures and suggestions to sovle the problems. 展开更多
关键词 marine instrument product standards marine monitoring high-quality marine technology
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基于Ethernet-APL的新型工业控制系统设计
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作者 李华军 王鸥 边文艺 《石油化工自动化》 CAS 2024年第3期5-8,共4页
两线制以太网Ethernet-APL通信技术,以其供电、高带宽、远距离、防爆设计成为目前工业领域最具潜力的现场通信技术,国内产业链正在积极推动Ethernet-APL芯片、仪表、交换机、控制系统的研发。从工业控制系统角度,提出了Ethernet-APL新... 两线制以太网Ethernet-APL通信技术,以其供电、高带宽、远距离、防爆设计成为目前工业领域最具潜力的现场通信技术,国内产业链正在积极推动Ethernet-APL芯片、仪表、交换机、控制系统的研发。从工业控制系统角度,提出了Ethernet-APL新型工业控制系统可能的应用场景以及与之匹配的系统架构。同时,也对该控制系统的网络负荷、实时性、网络冗余、仪表IP分配等关键技术提出了设计方案。随着该技术的推广,将会助力仪表智能化及工厂智能制造的实现。 展开更多
关键词 Ethernet-APL技术 工业控制系统 分散控制系统 仪表IP分配 网络冗余
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Ethernet-APL简介及在SIS系统的应用展望
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作者 马云龙 《宁波化工》 2024年第3期10-16,9,共8页
简述了以太网高级物理层(Ethernet-APL)技术的发展历程。针对化工装置对全厂控制系统高可靠性和复杂性的要求,从新的以太物理层开放标准用于过程自动化和现场仪表的角度出发,阐述了APL技术的特点及在流程工业的应用优势。介绍并分析了... 简述了以太网高级物理层(Ethernet-APL)技术的发展历程。针对化工装置对全厂控制系统高可靠性和复杂性的要求,从新的以太物理层开放标准用于过程自动化和现场仪表的角度出发,阐述了APL技术的特点及在流程工业的应用优势。介绍并分析了以太网高级物理层在SIS安全仪表系统的应用前景和系统架构的特征,以期为推动APL技术的应用提供参考。 展开更多
关键词 高级物理层 Ethernet-APL技术 两线制本质安全 安全仪表系统
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PROFIBUS-DP技术在石灰窑电气控制系统改造中的应用
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作者 邸敏艳 姚勇 +1 位作者 刘恒 李金鑫 《工业仪表与自动化装置》 2008年第5期55-58,共4页
详细介绍了在石灰窑电气控制系统中,利用嵌入式PROFIBUS-DP总线桥与用户单片机系统组成智能仪表,将传统的PLC控制方法改造为数据总线控制,在节约大量资金的同时提高了系统运行的可靠性和现场控制与改造的方便性。
关键词 数据总线技术 石灰窑 智能仪表 技术改造
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Design of Onboard Instrument Based on Virtual Instrument Technology 被引量:2
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作者 TANG Baoping ZHONG Yuanchang QIU Jianwei (Department of Mechatronics,College of Mechanical Engineering,Chongqing University,Chongqing 400030,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期412-416,共5页
After analyzing and comparing the traditional automobile instrument,the onboard instrument based on virtual instrument technology is designed in this paper.The PC/104 computer was employed as the core processing unit ... After analyzing and comparing the traditional automobile instrument,the onboard instrument based on virtual instrument technology is designed in this paper.The PC/104 computer was employed as the core processing unit of the onbaard in- strument,and the several intelligent data acquisition nodes are set and connected by the CAN bus,through which the nodes can com- municate with the core processing unit.The information of the vehicle’s working condition can be displayed synthetically by adopt- ing virtual instrument technology.When the working condition goes beyond its limit,the system can emit an alarm,record and storage the abnormal condition automatically,and suggest how to deal with the abnormity urgently.The development background and design idea of onboard information system were elaborated in the paper.The software,the hardware architecture and the principle of onboard information system were introduced in detail. 展开更多
关键词 VIRTUAL instrument EMBEDDED TECHNOLOGY PC/104 CAN BUS
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Feasibility study applied to mapping tidal effects in the Pannonian basin--An effort to check location dependencies atμGal level 被引量:1
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作者 G.Papp J.Benedek +5 位作者 P.Varga M.Kis A.Koppan B.Meurers R.Leonhardt M.K.Baracza 《Geodesy and Geodynamics》 2018年第3期237-245,共9页
This paper summarizes the main instrumental and methodological points of the tidal research which was performed in the framework of the National Scientific Research Fund Project K101603. Since the project is still run... This paper summarizes the main instrumental and methodological points of the tidal research which was performed in the framework of the National Scientific Research Fund Project K101603. Since the project is still running the tidal analysis results published here are only preliminary. Unmodelled tidal effects have been highlighted in some recent absolute gravity measurements carried out in the Pannonian basin resulting in a periodic modulation exceeding the typical standard deviations (±1microGal) of the drop sets. Since the most dominant source of the daily gravity variation is the bulk tidal effect, the goal of the project is to check its location dependency at BGal level. Unfortunately Hungary has had no dedicated instrumentation, so an effort was made to make the available LaCoste- Romberg spring G meters capable for continuous recording. As a reference instrument the GWR SG025 operated in the Conrad Observatory, Austria was also used and in the mean time of the project, a Scintrex CG-5 became also available, Eventually 6 instruments at 5 different locations were operated for 3 9 months mainly in co-located configuration. Although many experiments (moving mass calibrations) were done to determine the scale factors and scale functions of the instruments, the direct comparison of the tidal parameters obtained from the observations is still questionable. Therefore the ratio of the delta factors of O1 and M2 tidal constituents was investigated supposing that M2 is much more influenced by the ocean loading effect than O1. The slight detected increase of δ(O1 )/δ(M2) (≈0.2%) toward east does not contradict to theory. This result has to be validated in the near future by analyzing available ocean loading models. 展开更多
关键词 Gravity tide mapping Spring gravity meters Instrumental tests Co-located observations Location dependence of delta factors
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Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection 被引量:8
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作者 倪晋平 杨雷 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第4期275-280,共6页
For measuring velocity and impacting position of single fragment of warhead,a non-contact measuring method is proposed,in which a six-light-screen array,a position indicator,a multi-channel chronograph and a computer ... For measuring velocity and impacting position of single fragment of warhead,a non-contact measuring method is proposed,in which a six-light-screen array,a position indicator,a multi-channel chronograph and a computer are used.The principle of measurement is described.The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters.When the fragment flies through the light screen array,the time of passing through each of the screens is recorded by the multi-channel chronograph.According to the time data and the geometrical parameters of the array,the velocity vector and the location of the fragment can be calculated immediately.The presented method can be used to locate the fragment and to measure the real velocity on its flying direction.It can also be used to measure the velocity of a fragment swarm after the system is engineered further. 展开更多
关键词 弹头 速度 方向 光电检测 轨迹
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A New Micro-magnetism Sensor Based on Giant Magneto-impedance Effect and Multivibrator Bridge 被引量:1
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作者 孙骥 邓甲昊 蔡克荣 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第3期175-180,共6页
A novel sensor for micro-magnetic field detection is proposed based on the physical characteristics and giant magneto-impedance (GMI) effect of Fe-Co-Si-B amorphous wires. The sensor circuit ensures high sensitivity,h... A novel sensor for micro-magnetic field detection is proposed based on the physical characteristics and giant magneto-impedance (GMI) effect of Fe-Co-Si-B amorphous wires. The sensor circuit ensures high sensitivity,high detection precision,fast response and small power consumption. The signal processing circuit taking complex programmable logic device (CPLD) as core chip not only improves the identification ability for pseudo ferromagnetic objects,but also ensures the real-rime response. It is the foundation for the proposed sensor to serve widely in military and civil. By using its high sensitivity for geomagnetism variation,as an application example,the sensor is used to compare and analyze different cars. 展开更多
关键词 巨磁阻抗效应 磁传感器 多谐振荡 可编程逻辑器件 信号处理电路 高灵敏度 传感器检测 传感器电路
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Experimental Research on Jerk Characteristics of Tracked Vehicles at Starting Phase 被引量:2
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作者 张赤军 翟旭华 马宏 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第1期61-64,共4页
A new method is introduced to measure the three parameters of shake quantity,multi-barrel parallelism and zero line using the synthesis of laser collimation,CCD graphic recognized technique and hydraulic press techniq... A new method is introduced to measure the three parameters of shake quantity,multi-barrel parallelism and zero line using the synthesis of laser collimation,CCD graphic recognized technique and hydraulic press technique.The paper describes briefly the principle of the equipment and analyzes the uncertainty.The uncertainty is not more than 15″. 展开更多
关键词 火箭炮 摇摆量 水压系统 线性检查
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