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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
基金supported by the Research Center for Aging Career and Industrial Development,Sichuan Key Research Base of Social Sciences[Grant No.XJLL2022009].
文摘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.
文摘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).
文摘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.
文摘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.
基金Supported by National Natural Science Foundation of China(Grant Nos.52005441,51890885)open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems(Grant No.GZKF-201906)+1 种基金Zhejiang Province Natural Science Foundation of China(Grant No.LQ21E050017)China Postdoctoral Science Foundation(Grant Nos.2021M692777,2021T140594).
文摘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.
基金supported by the National Science Foundation of China (Grant Nos. 40830957 and 40575006)
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
基金the financial support of NKFIH-OTKA in the framework of contract K101603
文摘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.
基金Sponsored by Foundation of Department Education of Shaanxi Province of China(03JC31)Key Lab Foundationin Nanjing University of Science and Technology(51453010103SX0201).
文摘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.
基金Sponsored by National Natural Science Foundation of China (60874100)China Aerospace Science and Technology Innovation Funds (CAST200834)Weapons Advanced Research Funds (9140A01010109BQ0116)
文摘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.
文摘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″.