In the current state of geomagnetic instrument testing,some aspects of geomagnetic instrument performance are difficult to test in the laboratory.If laboratory test results are inadequate,the instrument will have mult...In the current state of geomagnetic instrument testing,some aspects of geomagnetic instrument performance are difficult to test in the laboratory.If laboratory test results are inadequate,the instrument will have multiple problems while operating in the field,where a geomagnetic instrumentation test platform with a stable natural magnetic field is critical.Here,the magnetic field feedback circuit for geomagnetic field compensation control is studied in detail.That is,the magnetic field measured by the feedback magnetic sensor and the required working magnetic field are compared as input to the system,and the electric signal is transmitted to the feedback coil through an analog circuit to form a closed loop control,which provides compensation to control the magnetic field.Compared with the existing magnetic shielding method,the analog control circuit can achieve the realization of any working magnetic field,and it is not limited to a null magnetic field.The experimental result shows that the system compensates the earth’s magnetic field of 10,000 nT with an average error of 10.6 nT and average compensation error of 0.106%,providing a high compensation accuracy.The system also shows high sensitivity and excellent stability.The feedback circuit has achieved effective compensation control for the earth’s magnetic field.展开更多
Kirsten rat sarcoma viral oncogene homolog(KRAS)mutation is associated with the poor prognosis of colorectal cancer(CRC)patients,but the therapeutic strategies targeting KRAS are limited,and novel intervention strateg...Kirsten rat sarcoma viral oncogene homolog(KRAS)mutation is associated with the poor prognosis of colorectal cancer(CRC)patients,but the therapeutic strategies targeting KRAS are limited,and novel intervention strategies are urgently needed.The dysfunction of deubiquitinases(DUBs)is widely involved in the progression of malignancy,and DUBs are considered ideal anti-tumor targets due to their well-defined structures and catalytic sites.In our study,through DUB inhibitors screening and liquid chromatography-tandem mass spectrometry(LC–MS/MS)analysis,we identified that ubiquitin-specific protease 10(USP10)functions as a potent DUB regulating KRAS mutants'activity.Mechanistically,USP10 directly binds to and promotes KRAS variants'activity across different mutants by removing the latter’s non-proteolytic ubiquitination chains mainly containing K6,K11,K27 and K29-linkage;while the activated KRAS mutants reciprocally upregulate USP10 levels by phosphorylating the latter at Thr42/Ser337,therefore forming a positive feedback circuit and synergistically promoting KRAS-mutant CRC growth.Moreover,we found that USP10 is elevated in KRAS-mutant CRC tissues and depletion of USP10 preferentially impeded KRAS-mutant CRC growth in vitro/in vivo.Our findings not only uncover the critical roles of the USP10/KRAS positive feedback circuit in promoting KRAS-mutant CRC growth,but also offer novel therapeutic strategies for CRC patients harboring KRAS variants across different mutants by targeting USP10.展开更多
This paper reports a new hyperchaotic system by adding an additional state variable into a three-dimensional chaotic dynamical system. Some of its basic dynamical properties, such as the hyperchaotic attractor, Lyapun...This paper reports a new hyperchaotic system by adding an additional state variable into a three-dimensional chaotic dynamical system. Some of its basic dynamical properties, such as the hyperchaotic attractor, Lyapunov expo- nents, bifurcation diagram and the hyperchaotic attractor evolving into periodic, quasi-periodic dynamical behaviours by varying parameter k are studied. An effective nonlinear feedback control method is used to suppress hyperchaos to unstable equilibrium. Furthermore, a circuit is designed to realize this new hyperchaotic system by electronic workbench （EWB）. Numerical simulations are presented to show these results.展开更多
基于高速低功耗混合应用场景下对互补金属氧化物半导体(Complementary Metal Oxide Semiconductor,CMOS)比较器性能的综合需求,系统研究其结构优化设计。阐述动态比较器在响应速度、功耗控制、输入失调与噪声抑制等方面的关键技术,介绍...基于高速低功耗混合应用场景下对互补金属氧化物半导体(Complementary Metal Oxide Semiconductor,CMOS)比较器性能的综合需求,系统研究其结构优化设计。阐述动态比较器在响应速度、功耗控制、输入失调与噪声抑制等方面的关键技术,介绍前置放大器、电源控制、闭环反馈及偏置电路的协同优化策略。结合65 nm CMOS工艺下的仿真测试结果,分析主要性能指标在典型工况下的表现,验证所提结构的可实现性与工程适应性。结果表明,该设计能够在低功耗约束下保持高速响应。展开更多
In this paper, the synchronization of the fractional-order generalized augmented Lti system is investigated. Based on the predictor--corrector method, we obtain phase portraits, bifurcation diagrams, Lyapunov exponent...In this paper, the synchronization of the fractional-order generalized augmented Lti system is investigated. Based on the predictor--corrector method, we obtain phase portraits, bifurcation diagrams, Lyapunov exponent spectra, and Poincar6 maps of the fractional-order system and find that a four-wing chaotic attractor exists in the system when the system pa- rameters change within certain ranges. Further, by varying the system parameters, rich dynamical behaviors occur in the 2.7-order system. According to the stability theory of a fractional-order linear system, and adopting the linearization by feedback method, we have designed a nonlinear feedback controller in our theoretical analysis to implement the synchro- nization of the drive system with the response system. In addition, the synchronization is also shown by an electronic circuit implementation for the 2.7-order system. The obtained experiment results accord with the theoretical analyses, which further demonstrate the feasibility and effectiveness of the proposed synchronization scheme.展开更多
Two simple voltage-controlled-oscillators (VCO) with linear tuning laws employing only a single current feedback operational amplifier (CFOA) in conjunction with two analog multipliers (AM) have been highlighted. The ...Two simple voltage-controlled-oscillators (VCO) with linear tuning laws employing only a single current feedback operational amplifier (CFOA) in conjunction with two analog multipliers (AM) have been highlighted. The workability of the presented VCOs has been demonstrated by experimental results based upon AD844 type CFOAs and AD534 type AMs.展开更多
直流电压互感器(direct circuit voltage transformers,DCVTs)的低压输出模拟信号采用电缆传输时既无电气隔离同时易受电磁干扰,因此提出了采用光纤高线性度传输模拟信号的方案。利用双光源-光电探测器分别构成传输通道和闭环负反馈通道...直流电压互感器(direct circuit voltage transformers,DCVTs)的低压输出模拟信号采用电缆传输时既无电气隔离同时易受电磁干扰,因此提出了采用光纤高线性度传输模拟信号的方案。利用双光源-光电探测器分别构成传输通道和闭环负反馈通道,负反馈通道的光电探测器变换电流反馈至输入端对电光-光电传输系数非线性进行抑制,通过控制系统模型分析了非线性抑制控制策略和非线性抑制效果,分析了模拟信号光纤传输系统的电路设计关键要素。对模拟信号光纤传输系统进行开环传输和闭环反馈传输非线性特性对比测试,结果表明,通过闭环负反馈的传输方案将模拟信号光纤传输非线性误差从百分之几提高到了±0.05%以内。最后将模拟信号光纤传输系统应用到DCVT中进行了线性度测试,试验结果表明:模拟信号光纤传输系统能很好地适用于直流配电网中模拟信号电气隔离和消除电磁干扰的应用需求。展开更多
基金National Key Research and Development Program Project(2018YFC1503803)Central-Level Public Welfare Basic Research Business Special(DQJB19B22)
文摘In the current state of geomagnetic instrument testing,some aspects of geomagnetic instrument performance are difficult to test in the laboratory.If laboratory test results are inadequate,the instrument will have multiple problems while operating in the field,where a geomagnetic instrumentation test platform with a stable natural magnetic field is critical.Here,the magnetic field feedback circuit for geomagnetic field compensation control is studied in detail.That is,the magnetic field measured by the feedback magnetic sensor and the required working magnetic field are compared as input to the system,and the electric signal is transmitted to the feedback coil through an analog circuit to form a closed loop control,which provides compensation to control the magnetic field.Compared with the existing magnetic shielding method,the analog control circuit can achieve the realization of any working magnetic field,and it is not limited to a null magnetic field.The experimental result shows that the system compensates the earth’s magnetic field of 10,000 nT with an average error of 10.6 nT and average compensation error of 0.106%,providing a high compensation accuracy.The system also shows high sensitivity and excellent stability.The feedback circuit has achieved effective compensation control for the earth’s magnetic field.
基金supported by the Natural Science Foundation of China(U21A20420,82173836,82304517)Zhejiang Provincial Natural Science Foundation(LQ23H310009,China).
文摘Kirsten rat sarcoma viral oncogene homolog(KRAS)mutation is associated with the poor prognosis of colorectal cancer(CRC)patients,but the therapeutic strategies targeting KRAS are limited,and novel intervention strategies are urgently needed.The dysfunction of deubiquitinases(DUBs)is widely involved in the progression of malignancy,and DUBs are considered ideal anti-tumor targets due to their well-defined structures and catalytic sites.In our study,through DUB inhibitors screening and liquid chromatography-tandem mass spectrometry(LC–MS/MS)analysis,we identified that ubiquitin-specific protease 10(USP10)functions as a potent DUB regulating KRAS mutants'activity.Mechanistically,USP10 directly binds to and promotes KRAS variants'activity across different mutants by removing the latter’s non-proteolytic ubiquitination chains mainly containing K6,K11,K27 and K29-linkage;while the activated KRAS mutants reciprocally upregulate USP10 levels by phosphorylating the latter at Thr42/Ser337,therefore forming a positive feedback circuit and synergistically promoting KRAS-mutant CRC growth.Moreover,we found that USP10 is elevated in KRAS-mutant CRC tissues and depletion of USP10 preferentially impeded KRAS-mutant CRC growth in vitro/in vivo.Our findings not only uncover the critical roles of the USP10/KRAS positive feedback circuit in promoting KRAS-mutant CRC growth,but also offer novel therapeutic strategies for CRC patients harboring KRAS variants across different mutants by targeting USP10.
基金Project supported by the National Natural Science Foundations of China (Grant Nos. 70571030 and 90610031)the Society Science Foundation from Ministry of Education of China (Grant No. 08JA790057)the Advanced Talents’ Foundation and Student’s Foundation of Jiangsu University (Grant Nos. 07JDG054 and 07A075)
文摘This paper reports a new hyperchaotic system by adding an additional state variable into a three-dimensional chaotic dynamical system. Some of its basic dynamical properties, such as the hyperchaotic attractor, Lyapunov expo- nents, bifurcation diagram and the hyperchaotic attractor evolving into periodic, quasi-periodic dynamical behaviours by varying parameter k are studied. An effective nonlinear feedback control method is used to suppress hyperchaos to unstable equilibrium. Furthermore, a circuit is designed to realize this new hyperchaotic system by electronic workbench （EWB）. Numerical simulations are presented to show these results.
基金supported by the National Natural Science Foundation of China(Grant No.61174094)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.11202148)
文摘In this paper, the synchronization of the fractional-order generalized augmented Lti system is investigated. Based on the predictor--corrector method, we obtain phase portraits, bifurcation diagrams, Lyapunov exponent spectra, and Poincar6 maps of the fractional-order system and find that a four-wing chaotic attractor exists in the system when the system pa- rameters change within certain ranges. Further, by varying the system parameters, rich dynamical behaviors occur in the 2.7-order system. According to the stability theory of a fractional-order linear system, and adopting the linearization by feedback method, we have designed a nonlinear feedback controller in our theoretical analysis to implement the synchro- nization of the drive system with the response system. In addition, the synchronization is also shown by an electronic circuit implementation for the 2.7-order system. The obtained experiment results accord with the theoretical analyses, which further demonstrate the feasibility and effectiveness of the proposed synchronization scheme.
文摘Two simple voltage-controlled-oscillators (VCO) with linear tuning laws employing only a single current feedback operational amplifier (CFOA) in conjunction with two analog multipliers (AM) have been highlighted. The workability of the presented VCOs has been demonstrated by experimental results based upon AD844 type CFOAs and AD534 type AMs.
文摘直流电压互感器(direct circuit voltage transformers,DCVTs)的低压输出模拟信号采用电缆传输时既无电气隔离同时易受电磁干扰,因此提出了采用光纤高线性度传输模拟信号的方案。利用双光源-光电探测器分别构成传输通道和闭环负反馈通道,负反馈通道的光电探测器变换电流反馈至输入端对电光-光电传输系数非线性进行抑制,通过控制系统模型分析了非线性抑制控制策略和非线性抑制效果,分析了模拟信号光纤传输系统的电路设计关键要素。对模拟信号光纤传输系统进行开环传输和闭环反馈传输非线性特性对比测试,结果表明,通过闭环负反馈的传输方案将模拟信号光纤传输非线性误差从百分之几提高到了±0.05%以内。最后将模拟信号光纤传输系统应用到DCVT中进行了线性度测试,试验结果表明:模拟信号光纤传输系统能很好地适用于直流配电网中模拟信号电气隔离和消除电磁干扰的应用需求。
