Background Compared with traditional biomagnetic field detection devices,such as superconducting quantum interference devices(SQUIDs)and atomic magnetometers,only giant magneto impedance(GMI)sensors can be applied for...Background Compared with traditional biomagnetic field detection devices,such as superconducting quantum interference devices(SQUIDs)and atomic magnetometers,only giant magneto impedance(GMI)sensors can be applied for unshielded human brain biomagnetic detection,and they have the potential for application in next-generation wearable equipment for brain-computer interfaces(BCIs).Achieving a better GMI sensor without magnetic shielding requires the stimulation of the GMI effect to be maximized and environmental noise interference to be minimized.Moreover,the GMI effect stimulated in an amorphous filament is closely related to its working point,which is sensitive to both the external magnetic field and the drive current of the filament.Methods In this paper,we propose a new noise reducing GMI gradiometer with a dual-loop self-adapting structure.Noise reduction is realized by a direction-flexible differential probe,and the dual-loop structure optimizes and stabilizes the working point by automatically controlling the external magnetic field and drive current.This dual-loop structure is fully program controlled by a micro control unit(MCU),which not only simplifies the traditional constant parameter sensor circuit,saving the time required to adjust the circuit component parameters,but also improves the sensor performance and environmental adaptation.Results In the performance test,within 2 min of self-adaptation,our sensor showed a better sensitivity and signal-to-noise ratio(SNR)than those of the traditional designs and achieved a background noise of 12 pT/√Hz at 10 Hz and 7pT/√Hz at 200 Hz.Conclusion To the best of our knowledge,our sensor is the first to realize self-adaptation of both the external magnetic field and the drive current.展开更多
At present, the overall economic benefits of construction projects in China are closely related to the quality of budget and settlement audit. The project cost runs through the whole process of the construction projec...At present, the overall economic benefits of construction projects in China are closely related to the quality of budget and settlement audit. The project cost runs through the whole process of the construction project. It is of positive significance to reduce the cost of the project cost and improve the economic benefits of the project by means of efficient project settlement audit. Construction projects have high requirements on construction quality. Ensuring the project construction within a given time and successfully completing the project completion can ensure the overall economic benefits of construction projects. Using scientific and reasonable cost control can improve the efficiency of budget and settlement audit of construction projects and maximize the economic benefits of construction projects.展开更多
A compact multi-throttle aerostatic guideway is the preferred structure for high precision and acceleration motion in the variable-slit system(VS)of photolithography.The presence of microstructure,such as recesses and...A compact multi-throttle aerostatic guideway is the preferred structure for high precision and acceleration motion in the variable-slit system(VS)of photolithography.The presence of microstructure,such as recesses and grooves,on the guideway working surface has been found to improve the loading performance.Nevertheless,the effects on the guideway performance of changing the microstructure on the micron level are not yet clear.The mesh adaptation method,which was proposed by the authors,is employed in this paper to quantitatively study the influences of four microstructure parameters.The effect of tuning these parameters on the loading performance is revealed.The level of impact determines the proposed design process of the parameters.The characteristic feature of the proposed design process is that the working points of carrying capacity,stiffness,and rotational stiffness are unified under twoway adjusting by means of recess parameters.According to the proposed design process and tuning method,the restriction of supply pressure is lifted to a certain extent and the mutual tradeoff among the loading performances is relieved.The experimental results show that the rotational stiffness of the designed guideway,based on the tuned parameters,reached 2.14×10^(4) Nmrad1 and increased by 69.8%.In a scanning test of the applied VS on argon fluoride laser(ArF)photolithography,the average scanning acceleration reached 67.5 m·s^(-2),meeting the design specification.展开更多
Animal husbandry is an important way to increase farmers' income, and it also has a vital impact on the overall development level of agricultural economy. In recent years, under the background of rapid social and ...Animal husbandry is an important way to increase farmers' income, and it also has a vital impact on the overall development level of agricultural economy. In recent years, under the background of rapid social and economic development, animal husbandry has made great progress in continuous upgrading and adjustment. In recent years, under the background of rapid socio-economic development, animal husbandry has made great progress with continuous upgrading and adjustment, and the scale of animal husbandry is expanding day by day, which more effectively ensures the output and quality of animal husbandry products. However, in the development of animal husbandry, animal epidemic prevention work of animal husbandry and veterinary medicine can not be separated from strong support, and animal epidemic prevention work plays an irreplaceable role in the development of animal husbandry. However, at present, there are still some problems and deficiencies in animal epidemic prevention work at grass-roots level, which affect the effective promotion of animal husbandry work. Based on this, this paper discusses the animal epidemic prevention work of grass-roots animal husbandry and veterinary.展开更多
Reconfigurable photonic integrated circuits(PICs)can implement arbitrary operations and signal processing functionalities directly in the optical domain.Run-time configuration of these circuits requires an electronic ...Reconfigurable photonic integrated circuits(PICs)can implement arbitrary operations and signal processing functionalities directly in the optical domain.Run-time configuration of these circuits requires an electronic control layer to adjust the working point of their building elements and compensate for thermal drifts or degradations of the input signal.As the advancement of photonic foundries enables the fabrication of chips of increasing complexity,developing scalable electronic controllers becomes crucial for the operation of complex PICs.In this paper,we present an electronic application-specific integrated circuit(ASIC)designed for reconfiguration of PICs featuring numerous tunable elements.Each channel of the ASIC controller independently addresses one optical component of the PIC,and multiple parallel local feedback loops are operated to achieve full control.The proposed design is validated through real-time reconfiguration of a 16-channel silicon photonics adaptive universal beam coupler.Results demonstrate automatic coupling of an arbitrary input beam to a single-mode waveguide,dynamic compensation of beam wavefront distortions and successful transmission of a 50 Gbit/s signal through an optical free-space link.The low power consumption and compactness of the electronic chip provide a scalable paradigm that can be seamlessly extended to larger photonic architectures.展开更多
A baseline design for the High Energy Photon Source has been proposed, with a natural emittance of 60 pm.rad within a circumference of about 1.3 kilometers. Nevertheless, the nonlinear performance of the design needs ...A baseline design for the High Energy Photon Source has been proposed, with a natural emittance of 60 pm.rad within a circumference of about 1.3 kilometers. Nevertheless, the nonlinear performance of the design needs further improvements to increase both the dynamic aperture and the momentum acceptance. In this study, genetic optimization of the linear optics is performed, so as to find all the possible solutions with weaker sextupoles and hence weaker nonlinearities, while keeping the emittance at the same level as the baseline design. The solutions obtained enable us to explore the dependence of nonlinear dynamics on the working point. The result indicates that with the same layout, it is feasible to obtain much better nonlinear performance with a delicate tuning of the magnetic field strengths and a wise choice of the working point.展开更多
Indus-2 is a synchrotron radiation source that is operational at RRCAT, Indore, India. It is essentially pertinent in any synchrotron radiation facility to store the electron beam without beam loss. During the day to ...Indus-2 is a synchrotron radiation source that is operational at RRCAT, Indore, India. It is essentially pertinent in any synchrotron radiation facility to store the electron beam without beam loss. During the day to day operation of Indus-2 storage ring, difficulty was being faced in accumulating higher beam current. After examination, it was found that the working point was shifting from its desired value during accumulation. For smooth beam accumulation, a fixed desired tune in both horizontal and vertical plane plays a significant role in avoiding beam loss via the resonance process. This required a betatron tune feedback system to be put in the storage ring. After putting ON this feedback, the beam accumulation was smooth. The details of this feedback and its working principle are described in this paper.展开更多
基金Supported by the China Postdoctoral Science Foundation(4139ZRL)the National Natural Science Foundation of China(U19A2083).
文摘Background Compared with traditional biomagnetic field detection devices,such as superconducting quantum interference devices(SQUIDs)and atomic magnetometers,only giant magneto impedance(GMI)sensors can be applied for unshielded human brain biomagnetic detection,and they have the potential for application in next-generation wearable equipment for brain-computer interfaces(BCIs).Achieving a better GMI sensor without magnetic shielding requires the stimulation of the GMI effect to be maximized and environmental noise interference to be minimized.Moreover,the GMI effect stimulated in an amorphous filament is closely related to its working point,which is sensitive to both the external magnetic field and the drive current of the filament.Methods In this paper,we propose a new noise reducing GMI gradiometer with a dual-loop self-adapting structure.Noise reduction is realized by a direction-flexible differential probe,and the dual-loop structure optimizes and stabilizes the working point by automatically controlling the external magnetic field and drive current.This dual-loop structure is fully program controlled by a micro control unit(MCU),which not only simplifies the traditional constant parameter sensor circuit,saving the time required to adjust the circuit component parameters,but also improves the sensor performance and environmental adaptation.Results In the performance test,within 2 min of self-adaptation,our sensor showed a better sensitivity and signal-to-noise ratio(SNR)than those of the traditional designs and achieved a background noise of 12 pT/√Hz at 10 Hz and 7pT/√Hz at 200 Hz.Conclusion To the best of our knowledge,our sensor is the first to realize self-adaptation of both the external magnetic field and the drive current.
文摘At present, the overall economic benefits of construction projects in China are closely related to the quality of budget and settlement audit. The project cost runs through the whole process of the construction project. It is of positive significance to reduce the cost of the project cost and improve the economic benefits of the project by means of efficient project settlement audit. Construction projects have high requirements on construction quality. Ensuring the project construction within a given time and successfully completing the project completion can ensure the overall economic benefits of construction projects. Using scientific and reasonable cost control can improve the efficiency of budget and settlement audit of construction projects and maximize the economic benefits of construction projects.
基金This work was funded by the National Natural Science Foundation of China(51675136)the National Science and Technology Major Project(2017ZX02101006-005)the Heilongjiang Natural Science Foundation(E2017032).
文摘A compact multi-throttle aerostatic guideway is the preferred structure for high precision and acceleration motion in the variable-slit system(VS)of photolithography.The presence of microstructure,such as recesses and grooves,on the guideway working surface has been found to improve the loading performance.Nevertheless,the effects on the guideway performance of changing the microstructure on the micron level are not yet clear.The mesh adaptation method,which was proposed by the authors,is employed in this paper to quantitatively study the influences of four microstructure parameters.The effect of tuning these parameters on the loading performance is revealed.The level of impact determines the proposed design process of the parameters.The characteristic feature of the proposed design process is that the working points of carrying capacity,stiffness,and rotational stiffness are unified under twoway adjusting by means of recess parameters.According to the proposed design process and tuning method,the restriction of supply pressure is lifted to a certain extent and the mutual tradeoff among the loading performances is relieved.The experimental results show that the rotational stiffness of the designed guideway,based on the tuned parameters,reached 2.14×10^(4) Nmrad1 and increased by 69.8%.In a scanning test of the applied VS on argon fluoride laser(ArF)photolithography,the average scanning acceleration reached 67.5 m·s^(-2),meeting the design specification.
文摘Animal husbandry is an important way to increase farmers' income, and it also has a vital impact on the overall development level of agricultural economy. In recent years, under the background of rapid social and economic development, animal husbandry has made great progress in continuous upgrading and adjustment. In recent years, under the background of rapid socio-economic development, animal husbandry has made great progress with continuous upgrading and adjustment, and the scale of animal husbandry is expanding day by day, which more effectively ensures the output and quality of animal husbandry products. However, in the development of animal husbandry, animal epidemic prevention work of animal husbandry and veterinary medicine can not be separated from strong support, and animal epidemic prevention work plays an irreplaceable role in the development of animal husbandry. However, at present, there are still some problems and deficiencies in animal epidemic prevention work at grass-roots level, which affect the effective promotion of animal husbandry work. Based on this, this paper discusses the animal epidemic prevention work of grass-roots animal husbandry and veterinary.
基金supported by the Italian National Recovery and Resilience Plan(NRRP)of Nex tGeneration EU,partnership on“Telecommunications of the Future”(Program“RESTART”,Structural Project“Rigoletto,”and Focused Project“HePIC”)under Grant PE00000001.We thank Polifab,the nanofabrication facility of Politecnico di Milano,for dicing and wire-bonding the chips.
文摘Reconfigurable photonic integrated circuits(PICs)can implement arbitrary operations and signal processing functionalities directly in the optical domain.Run-time configuration of these circuits requires an electronic control layer to adjust the working point of their building elements and compensate for thermal drifts or degradations of the input signal.As the advancement of photonic foundries enables the fabrication of chips of increasing complexity,developing scalable electronic controllers becomes crucial for the operation of complex PICs.In this paper,we present an electronic application-specific integrated circuit(ASIC)designed for reconfiguration of PICs featuring numerous tunable elements.Each channel of the ASIC controller independently addresses one optical component of the PIC,and multiple parallel local feedback loops are operated to achieve full control.The proposed design is validated through real-time reconfiguration of a 16-channel silicon photonics adaptive universal beam coupler.Results demonstrate automatic coupling of an arbitrary input beam to a single-mode waveguide,dynamic compensation of beam wavefront distortions and successful transmission of a 50 Gbit/s signal through an optical free-space link.The low power consumption and compactness of the electronic chip provide a scalable paradigm that can be seamlessly extended to larger photonic architectures.
基金Supported by NSFC(11475202,11405187)Youth Innovation Promotion Association CAS(2015009)
文摘A baseline design for the High Energy Photon Source has been proposed, with a natural emittance of 60 pm.rad within a circumference of about 1.3 kilometers. Nevertheless, the nonlinear performance of the design needs further improvements to increase both the dynamic aperture and the momentum acceptance. In this study, genetic optimization of the linear optics is performed, so as to find all the possible solutions with weaker sextupoles and hence weaker nonlinearities, while keeping the emittance at the same level as the baseline design. The solutions obtained enable us to explore the dependence of nonlinear dynamics on the working point. The result indicates that with the same layout, it is feasible to obtain much better nonlinear performance with a delicate tuning of the magnetic field strengths and a wise choice of the working point.
文摘Indus-2 is a synchrotron radiation source that is operational at RRCAT, Indore, India. It is essentially pertinent in any synchrotron radiation facility to store the electron beam without beam loss. During the day to day operation of Indus-2 storage ring, difficulty was being faced in accumulating higher beam current. After examination, it was found that the working point was shifting from its desired value during accumulation. For smooth beam accumulation, a fixed desired tune in both horizontal and vertical plane plays a significant role in avoiding beam loss via the resonance process. This required a betatron tune feedback system to be put in the storage ring. After putting ON this feedback, the beam accumulation was smooth. The details of this feedback and its working principle are described in this paper.
