This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems （SIHSs）. The performance of SIHSs is presented in brief with a discussion of several possib...This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems （SIHSs）. The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.展开更多
In the field of quantum communication,quantum steganography is an important branch of quantum information hiding.In a realistic quantum communication system,quantum noises are unavoidable and will seriously impact the...In the field of quantum communication,quantum steganography is an important branch of quantum information hiding.In a realistic quantum communication system,quantum noises are unavoidable and will seriously impact the safety and reliability of the quantum steganographic system.Therefore,it is very important to analyze the influence of noise on the quantum steganography protocol and how to reduce the effect of noise.This paper takes the quantum steganography protocol proposed in 2010 as an example to analyze the effects of noises on information qubits and secret message qubits in the four primary quantum noise environments.The results show that when the noise factor of one quantum channel noise is known,the size of the noise factor of the other quantum channel can be adjusted accordingly,such as artificially applying noise,so that the influence of noises on the protocol is minimized.In addition,this paper also proposes a method of improving the efficiency of the steganographic protocol in a noisy environment.展开更多
The pulse time of arrival （TOA） is a determining parameter for accurate timing and positioning in X-ray pulsar navigation. The pulse TOA can be calculated by comparing the measured arrival time with the predicted ar...The pulse time of arrival （TOA） is a determining parameter for accurate timing and positioning in X-ray pulsar navigation. The pulse TOA can be calculated by comparing the measured arrival time with the predicted arrival time of the X-ray pulse for pulsar. In this study, in order to research the measurement of pulse arrival time, an experimental system is set up. The experimental system comprises a simulator of the X-ray pulsar, an X-ray detector, a time-measurement system, and a data-processing system. An X-ray detector base is proposed on the basis of the micro-channel plate （MCP）, which is sensitive to soft X-ray in the 1–10 keV band. The MCP-based detector, the structure and principle of the experimental system, and results of the pulse profile are described in detail. In addition, a discussion of the effects of different X-ray pulse periods and the quantum efficiency of the detector on pulse-profile signal-to-noise ratio （SNR） is presented. Experimental results reveal that the SNR of the measured pulse profile becomes enhanced as the quantum efficiency of the detector increases. The SNR of the pulse profile is higher when the period of the pulse is smaller at the same integral.展开更多
研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采...研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采用开关模型、噪声模型和非线性大信号模型进行联合仿真设计。测试结果表明,该收发一体多功能芯片在23~25 GHz范围内,接收支路增益23 d B、噪声系数2.5 d B,工作电流仅为12 m A;发射支路增益为30 d B,1 d B压缩点输出功率为18.7 d Bm,功率附加效率达到30%,动态电流仅为70 m A。芯片尺寸小,仅为3.5 mm×2.5 mm。展开更多
文摘This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems （SIHSs）. The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.
基金This work was supported by the National Natural Science Foundation of China(Nos.61373131,61303039,61232016,61501247)the Six Talent Peaks Project of Jiangsu Province(Grant No.2015-XXRJ-013)+3 种基金Natural Science Foundation of Jiangsu Province(Grant No.BK20171458)the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(China under Grant No.16KJB520030)Sichuan Youth Science and Technique Foundation(No.2017JQ0048)NUIST Research Foundation for Talented Scholars(2015r014),PAPD and CICAEET funds.
文摘In the field of quantum communication,quantum steganography is an important branch of quantum information hiding.In a realistic quantum communication system,quantum noises are unavoidable and will seriously impact the safety and reliability of the quantum steganographic system.Therefore,it is very important to analyze the influence of noise on the quantum steganography protocol and how to reduce the effect of noise.This paper takes the quantum steganography protocol proposed in 2010 as an example to analyze the effects of noises on information qubits and secret message qubits in the four primary quantum noise environments.The results show that when the noise factor of one quantum channel noise is known,the size of the noise factor of the other quantum channel can be adjusted accordingly,such as artificially applying noise,so that the influence of noises on the protocol is minimized.In addition,this paper also proposes a method of improving the efficiency of the steganographic protocol in a noisy environment.
文摘The pulse time of arrival （TOA） is a determining parameter for accurate timing and positioning in X-ray pulsar navigation. The pulse TOA can be calculated by comparing the measured arrival time with the predicted arrival time of the X-ray pulse for pulsar. In this study, in order to research the measurement of pulse arrival time, an experimental system is set up. The experimental system comprises a simulator of the X-ray pulsar, an X-ray detector, a time-measurement system, and a data-processing system. An X-ray detector base is proposed on the basis of the micro-channel plate （MCP）, which is sensitive to soft X-ray in the 1–10 keV band. The MCP-based detector, the structure and principle of the experimental system, and results of the pulse profile are described in detail. In addition, a discussion of the effects of different X-ray pulse periods and the quantum efficiency of the detector on pulse-profile signal-to-noise ratio （SNR） is presented. Experimental results reveal that the SNR of the measured pulse profile becomes enhanced as the quantum efficiency of the detector increases. The SNR of the pulse profile is higher when the period of the pulse is smaller at the same integral.
文摘研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采用开关模型、噪声模型和非线性大信号模型进行联合仿真设计。测试结果表明,该收发一体多功能芯片在23~25 GHz范围内,接收支路增益23 d B、噪声系数2.5 d B,工作电流仅为12 m A;发射支路增益为30 d B,1 d B压缩点输出功率为18.7 d Bm,功率附加效率达到30%,动态电流仅为70 m A。芯片尺寸小,仅为3.5 mm×2.5 mm。
