The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the posit...The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.展开更多
A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tra...A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tracking stations.The definite segment in which robot existing can be detected and thisis long-range localization.Ultra-long wave(ULW)is adopted to solve the problem of metallic shieldingand realize effective communication between inside and outside of pipeline.ULW emitter is carried byrobot.When the plant is broken or defects on pipe-wall are inspected,the robot will stop moving.Anten-na array is presented and disposed upon the definite segment to search the accurate location of robot,andthis is short-range localization.In this paper,five-antenna array is adopted and an effective linear signalfusion algorithm is presented.The localization precision reaches R < 25cm.By tests in Shengli oil field,the whole system is verified with robust solutions.展开更多
The following paper is a brief theoretical approach to the state of the art in relation to the new demands of society in the area of climate and weather-related services for health. Apart from the study of the impacts...The following paper is a brief theoretical approach to the state of the art in relation to the new demands of society in the area of climate and weather-related services for health. Apart from the study of the impacts of climate change on health which requires a longer consideration, a special emphasis is given to the area of weather-related services based on biometeorological forecasting. A new way of understanding the interaction between atmospheric factors and living organisms is presented and some biometeorological indexes already developed are shown. Customized biometeorological services must be constructed in the field of human health based on the ICTs development and the amount of climatic data available but new approaches and scientific methods are required to success in achieving this enterprise.展开更多
China's aerospace industry is facing a major task of increasing the reform of aerospace management system and speeding up civil-military integration, which leads to an urgent demand for new aerospace think tank pr...China's aerospace industry is facing a major task of increasing the reform of aerospace management system and speeding up civil-military integration, which leads to an urgent demand for new aerospace think tank products. Thankfully, with "information space" as the carrier, the "systems science" as the guidance, and QIAN Xuesen's "metasynthetic wisdom system" as the core, QIAN Xuesen think tank provides the decision support for China to develop an aerospace knowledge economy and to continuously enhance the "space soft power". In this paper, the framework of the meta-synthetic wisdom system guided by systems science is presented, the relationship between basic ideas of QIAN Xuesen think tank and meta-synthetic wisdom system is explained and the construction items of aerospace hall of the workshop for meta-synthetic engineering(aerospace HWMSE) are analyzed.展开更多
The artificial neural network model which forecasts Open Mining Slope stability is established by neural network theory and method. The nonlinear reflection relation between stability target of open mining slope and i...The artificial neural network model which forecasts Open Mining Slope stability is established by neural network theory and method. The nonlinear reflection relation between stability target of open mining slope and its influence factor is described. The method of forecasting Open Mining Slope stability is brought forward.展开更多
基金National Science and Technology Major Project of China(No.DHZX01A02004)
文摘The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.
基金Supported by the High Technology Research and Development Programme of China (No. 2006AA04Z205)
文摘A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tracking stations.The definite segment in which robot existing can be detected and thisis long-range localization.Ultra-long wave(ULW)is adopted to solve the problem of metallic shieldingand realize effective communication between inside and outside of pipeline.ULW emitter is carried byrobot.When the plant is broken or defects on pipe-wall are inspected,the robot will stop moving.Anten-na array is presented and disposed upon the definite segment to search the accurate location of robot,andthis is short-range localization.In this paper,five-antenna array is adopted and an effective linear signalfusion algorithm is presented.The localization precision reaches R < 25cm.By tests in Shengli oil field,the whole system is verified with robust solutions.
文摘The following paper is a brief theoretical approach to the state of the art in relation to the new demands of society in the area of climate and weather-related services for health. Apart from the study of the impacts of climate change on health which requires a longer consideration, a special emphasis is given to the area of weather-related services based on biometeorological forecasting. A new way of understanding the interaction between atmospheric factors and living organisms is presented and some biometeorological indexes already developed are shown. Customized biometeorological services must be constructed in the field of human health based on the ICTs development and the amount of climatic data available but new approaches and scientific methods are required to success in achieving this enterprise.
文摘China's aerospace industry is facing a major task of increasing the reform of aerospace management system and speeding up civil-military integration, which leads to an urgent demand for new aerospace think tank products. Thankfully, with "information space" as the carrier, the "systems science" as the guidance, and QIAN Xuesen's "metasynthetic wisdom system" as the core, QIAN Xuesen think tank provides the decision support for China to develop an aerospace knowledge economy and to continuously enhance the "space soft power". In this paper, the framework of the meta-synthetic wisdom system guided by systems science is presented, the relationship between basic ideas of QIAN Xuesen think tank and meta-synthetic wisdom system is explained and the construction items of aerospace hall of the workshop for meta-synthetic engineering(aerospace HWMSE) are analyzed.
文摘The artificial neural network model which forecasts Open Mining Slope stability is established by neural network theory and method. The nonlinear reflection relation between stability target of open mining slope and its influence factor is described. The method of forecasting Open Mining Slope stability is brought forward.
