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Improvement and security analysis of multi-ring discrete modulation continuous variable quantum secret sharing scheme
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作者 姜欢窈 聂敏 +3 位作者 杨光 孙爱晶 张美玲 裴昌幸 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期189-197,共9页
In order to avoid the complexity of Gaussian modulation and the problem that the traditional point-to-point communication DM-CVQKD protocol cannot meet the demand for multi-user key sharing at the same time, we propos... In order to avoid the complexity of Gaussian modulation and the problem that the traditional point-to-point communication DM-CVQKD protocol cannot meet the demand for multi-user key sharing at the same time, we propose a multi-ring discrete modulation continuous variable quantum key sharing scheme(MR-DM-CVQSS). In this paper, we primarily compare single-ring and multi-ring M-symbol amplitude and phase-shift keying modulations. We analyze their asymptotic key rates against collective attacks and consider the security key rates under finite-size effects. Leveraging the characteristics of discrete modulation, we improve the quantum secret sharing scheme. Non-dealer participants only require simple phase shifters to complete quantum secret sharing. We also provide the general design of the MR-DM-CVQSS protocol.We conduct a comprehensive analysis of the improved protocol's performance, confirming that the enhancement through multi-ring M-PSK allows for longer-distance quantum key distribution. Additionally, it reduces the deployment complexity of the system, thereby increasing the practical value. 展开更多
关键词 discrete modulation continuous variable quantum secret sharing scheme
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Lifetime estimation of IGBT module using square-wave loss discretization and power cycling test 被引量:1
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作者 Jie Wang Da-Qing Gao +1 位作者 Wan-Zeng Shen Hong-Bin Yan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第10期126-138,共13页
The insulated gate bipolar transistor(IGBT)module is one of the most age-affected components in the switch power supply, and its reliability prediction is conducive to timely troubleshooting and reduction in safety ri... The insulated gate bipolar transistor(IGBT)module is one of the most age-affected components in the switch power supply, and its reliability prediction is conducive to timely troubleshooting and reduction in safety risks and unnecessary costs. The pulsed current pattern of the accelerator power supply is different from other converter applications;therefore, this study proposed a lifetime estimation method for IGBT modules in pulsed power supplies for accelerator magnets. The proposed methodology was based on junction temperature calculations using square-wave loss discretization and thermal modeling.Comparison results showed that the junction temperature error between the simulation and IR measurements was less than 3%. An AC power cycling test under real pulsed power supply applications was performed via offline wearout monitoring of the tested power IGBT module. After combining the IGBT4 PC curve and fitting the test results,a simple corrected lifetime model was developed to quantitatively evaluate the lifetime of the IGBT module,which can be employed for the accelerator pulsed power supply in engineering. This method can be applied to other IGBT modules and pulsed power supplies. 展开更多
关键词 IGBT module Junction temperature Power cycling test Lifetime prediction Power loss discretization
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Modulational instability of a resonantly polariton condensate in discrete lattices
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作者 漆伟 郭晓刚 +1 位作者 董亮伟 张晓斐 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期143-146,共4页
We study modulational instability of a resonantly polariton condensate in a discrete lattice.Employing a discrete gain-saturation model,we derive the dispersion relation for the modulational instability by means of th... We study modulational instability of a resonantly polariton condensate in a discrete lattice.Employing a discrete gain-saturation model,we derive the dispersion relation for the modulational instability by means of the linear-stability analysis.Effects of the pumping strength,the nonlinearity,the strength of the detuning,and the coupling strength on the modulation instability are investigated.It is found that the interplay between these parameters will dramatically change the modulational instability condition.We believe that the predicted results in this work can be useful for future possible experiment of exciton-polariton condensate in lattices. 展开更多
关键词 modulational instability polariton condensate discrete lattices
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The Asian Option Pricing when Discrete Dividends Follow a Markov-Modulated Model
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作者 Yingyi Fang Huisheng Shu +2 位作者 Xiu Kan Xin Zhang Zhiwei Zheng 《Open Journal of Statistics》 2017年第6期1067-1080,共14页
This paper is concerned with the pricing problem of the discrete arithmetic average Asian call option while the discrete dividends follow geometric Brownian motion. The volatility of the dividends model depends on the... This paper is concerned with the pricing problem of the discrete arithmetic average Asian call option while the discrete dividends follow geometric Brownian motion. The volatility of the dividends model depends on the Markov-Modulated process. The binomial tree method, in which a more accurate factor has been used, is applied to solve the corresponding pricing problem. Finally, a numerical example with simulations is presented to demonstrate the effectiveness of the proposed method. 展开更多
关键词 Arithmetic Average Asian Call option discrete DIVIDENDS Geometric BRoWNIAN Motion Markov-modulated VoLATILITY BINoMIAL Tree
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Solitary Wave Solutions of Discrete Complex Ginzburg-Landau Equation by Modified Adomian Decomposition Method 被引量:1
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作者 WANG Yue-Yue DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期81-89,共9页
In this paper, exact and numerical solutions are calculated for discrete complex Ginzburg-Landau equation with initial condition by considering the modified Adomian decomposition method (mADM), which is an efficient... In this paper, exact and numerical solutions are calculated for discrete complex Ginzburg-Landau equation with initial condition by considering the modified Adomian decomposition method (mADM), which is an efficient method and does not need linearization, weak nonlinearity assumptions or perturbation theory. The numerical solutions are also compared with their corresponding analytical solutions. It is shown that a very good approximation is achieved with the analytical solutions. Finally, the modulational instability is investigated and the corresponding condition is given. 展开更多
关键词 discrete complex Ginzburg-Landau equation modified Adomian decomposition method solitary wave solutions modulational instability
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Walsh Hadamard Transform Based Transceiver Design for SC-FDMA with Discrete Wavelet Transform 被引量:2
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作者 Arsla Khan Amna Arif +1 位作者 Tabassum Nawaz Sobia Baig 《China Communications》 SCIE CSCD 2017年第5期193-206,共14页
This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency ... This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency division multiple access(OFDMA)with extra advantage of low Peak to Average Power Ratio(PAPR). Moreover,this article also suggests the application of Walsh Hadamard transform(WHT)for linear precoding(LP)to improve the PAPR performance of the system. Supremacy of the proposed transceiver over conventional Fast Fourier transform(FFT)based SCFDMA is shown through simulated results in terms of PAPR,spectral efficiency(SE)and bit error rate(BER). 展开更多
关键词 multicarrier modulation orthogonal frequency division multiple access single carrier frequency division multiple access: fast Fourier transform discrete wavelet transform Walsh Hadamard transform
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A discrete multi-swarm optimizer for radio frequency identification network scheduling 被引量:1
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作者 陈瀚宁 朱云龙 《Journal of Central South University》 SCIE EI CAS 2014年第1期199-212,共14页
Due to the effectiveness, simple deployment and low cost, radio frequency identification (RFID) systems are used in a variety of applications to uniquely identify physical objects. The operation of RFID systems ofte... Due to the effectiveness, simple deployment and low cost, radio frequency identification (RFID) systems are used in a variety of applications to uniquely identify physical objects. The operation of RFID systems often involves a situation in which multiple readers physically located near one another may interfere with one another's operation. Such reader collision must be minimized to avoid the faulty or miss reads. Specifically, scheduling the colliding RFID readers to reduce the total system transaction time or response time is the challenging problem for large-scale RFID network deployment. Therefore, the aim of this work is to use a successful multi-swarm cooperative optimizer called pseo to minimize both the reader-to-reader interference and total system transaction time in RFID reader networks. The main idea of pS20 is to extend the single population PSO to the interacting multi-swarm model by constructing hierarchical interaction topology and enhanced dynamical update equations. As the RFID network scheduling model formulated in this work is a discrete problem, a binary version of PS20 algorithm is proposed. With seven discrete benchmark functions, PS20 is proved to have significantly better performance than the original PSO and a binary genetic algorithm, pS20 is then used for solving the real-world RFID network scheduling problem. Numerical results for four test cases with different scales, ranging from 30 to 200 readers, demonstrate the performance of the proposed methodology. 展开更多
关键词 reader interference RFID network scheduling pS2o swarm intelligence discrete optimization
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Filtered Ring Derived from Discrete Valuation Ring and Its Properties
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作者 M. H. Anjom Shoa M. H. Hosseini 《Advances in Pure Mathematics》 2014年第3期71-75,共5页
In this paper we show that if R is a discrete valuation ring, then R is a filtered ring. We prove some properties and relation when R is a discrete valuation ring.
关键词 CoMMUTATIVE RING VALUATIoN RING discrete VALUATIoN RING Filtered RING GRADED RING Filtered module GRADED module
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New bounds on the mutual information for discrete constellations and application to wireless channel estimation
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作者 A.Taufiq Asyhari 《Digital Communications and Networks》 SCIE 2020年第4期542-546,共5页
The lack of closed-form expressions of the mutual information for discrete constellations has limited its uses for analyzing reliable communication over wireless fading channels.In order to address this issue,this pap... The lack of closed-form expressions of the mutual information for discrete constellations has limited its uses for analyzing reliable communication over wireless fading channels.In order to address this issue,this paper proposes analytically-tractable lower bounds on the mutual information based on Arithmetic-Mean-Geometric-Mean(AMGM)inequality.The new bounds can apply to a wide range of discrete constellations and reveal some insights into the rate behavior at moderate to high Signal-to-Noise Ratio(SNR)values.The usability of the bounds is further demonstrated to approximate the optimum pilot overhead in stationary fading channels. 展开更多
关键词 Channel estimation Coded modulation discrete constellations Mutual information Wireless communications
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Generalized Parseval’s Theorem on Fractional Fourier Transform for Discrete Signals and Filtering of LFM Signals 被引量:1
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作者 Xiaotong Wang Guanlei Xu +2 位作者 Yue Ma Lijia Zhou Longtao Wang 《Journal of Signal and Information Processing》 2013年第3期274-281,共8页
This paper investigates the generalized Parseval’s theorem of fractional Fourier transform (FRFT) for concentrated data. Also, in the framework of multiple FRFT domains, Parseval’s theorem reduces to an inequality w... This paper investigates the generalized Parseval’s theorem of fractional Fourier transform (FRFT) for concentrated data. Also, in the framework of multiple FRFT domains, Parseval’s theorem reduces to an inequality with lower and upper bounds associated with FRFT parameters, named as generalized Parseval’s theorem by us. These results theoretically provide potential valuable applications in filtering, and examples of filtering for LFM signals in FRFT domains are demonstrated to support the derived conclusions. 展开更多
关键词 discrete Fractional FoURIER Transform (DFRFT) Uncertainty Principle Frequency-Limiting operator Linear FREQUENCY-modulATIoN (LFM) Signal FILTERING
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虚拟I/O模块在DCS以太网通信接口模块上的实现
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作者 徐卫峰 卢海松 +1 位作者 蔡丹 娄清辉 《自动化应用》 2024年第6期72-74,共3页
为减少硬件模块的重复开发,在保留原DCS软硬件系统架构不变的基础上,在以太网通信接口模块硬件上虚拟不同的I/O模块。虚拟I/O模块与硬点I/O模块具有一致的输入、输出及参数属性,且组态方式和产物格式一致。同一以太网通信模块上可在不... 为减少硬件模块的重复开发,在保留原DCS软硬件系统架构不变的基础上,在以太网通信接口模块硬件上虚拟不同的I/O模块。虚拟I/O模块与硬点I/O模块具有一致的输入、输出及参数属性,且组态方式和产物格式一致。同一以太网通信模块上可在不同的虚拟I/O槽位上配置不同的虚拟I/O模块,如Modbus TCP虚拟I/O模块和GOOSE虚拟I/O模块,进而在同一硬件实现不同的通信功能。虚拟I/O模块的使用一方面减少了DCS系统硬件模块的种类,简化备品备件,另一方面也提高了通信扩展的灵活性和便利性。 展开更多
关键词 虚拟i/o模块 DCS系统 以太网通信接口模块 Modbus TCP GooSE
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多分量LFM干扰及动态环境下DBOC信号的捕获
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作者 张天骐 唐娟 +1 位作者 谭霜 沈夕文 《信号处理》 CSCD 北大核心 2024年第7期1287-1297,共11页
针对双二进制偏移载波(double binary offset carrier,DBOC)信号在多分量线性调频(linear frequency modulation,LFM)干扰和动态环境下捕获算法缺乏的问题,提出布莱克曼窗预处理结合分数阶傅里叶变换(fractionalFouriertransform,FRFT)... 针对双二进制偏移载波(double binary offset carrier,DBOC)信号在多分量线性调频(linear frequency modulation,LFM)干扰和动态环境下捕获算法缺乏的问题,提出布莱克曼窗预处理结合分数阶傅里叶变换(fractionalFouriertransform,FRFT)的干扰抑制算法以及离散多项式相位变换(discretepolynomial-phase transform,DPT)、部分匹配滤波器(partial matching filter,PMF)结合快速傅里叶变换(fast Fourier transform,FFT)加频谱校正的捕获算法。该算法首先对接收信号做布莱克曼窗预处理,抑制干扰谱线输出旁瓣,提高干扰汇聚的精确性;然后利用分级算法快速搜索信号的最优阶数,在保证精度量级的条件下减少了运算量;最后,在对应的最优阶数下做FRFT,结合干扰判断和轮询算法,逐个完成多分量LFM干扰的抑制。对干扰抑制后的信号首先利用定阶算法确定其动态阶数;然后通过DPT对动态信号做降阶处理,去除动态项;最后利用PMF-FFT加频谱校正完成DBOC信号的捕获。仿真结果表明,所提算法能够准确并完全地对三个LFM干扰分量进行逐个抑制,且抑制后的干扰分量不会对其他干扰分量的抑制造成影响。在检测概率达到1时,经过布莱克曼窗预处理后算法的信噪比比经过汉明窗预处理和经过凯塞窗预处理后算法的信噪比分别提升了4 dB和6.4 dB,比未经过预处理算法的信噪比提升了7.2 dB。此外,使用频谱校正可以突出捕获峰值,提高捕获精度。与未经频谱校正算法相比,经过频谱校正后算法的信噪比提升了1.6 dB,且能减少一定的捕获时间。 展开更多
关键词 多分量线性调频干扰 预处理 分数阶傅里叶变换 离散多项式相位变换 频谱校正
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Thickness-modulated in-plane Bi2O2Se homojunctions for ultrafast high-performance photodetectors 被引量:3
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作者 Cheng-Yun Hong Gang-Feng Huang +2 位作者 Wen-Wen Yao Jia-Jun Deng Xiao-Long Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期363-369,共7页
Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored ... Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored in the photodetecting area. Considering the fact that the electrical properties such as carrier mobility, work function, and energy band structure of Bi2O2Se are thickness-dependent, the in-plane Bi2O2Se homojunctions consisting of layers with different thicknesses are successfully synthesized by the chemical vapor deposition(CVD) method across the terraces on the mica substrates,where terraces are created in the mica surface layer peeling off process. In this way, effective internal electrical fields are built up along the Bi2O2Se homojunctions, exhibiting diode-like rectification behavior with an on/off ratio of 102, what is more, thus obtained photodetectors possess highly sensitive and ultrafast features, with a maximum photoresponsivity of 2.5 A/W and a lifetime of 4.8 μs. Comparing with the Bi2O2Se uniform thin films, the photo-electric conversion efficiency is greatly improved for the in-plane homojunctions. 展开更多
关键词 Bi2o2Se in-plane homojunction thickness modulation PHoToDETECToRS
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Analysis and Design of Wireless Networked Control System Utilizing Adaptive Coded ModulationAnalysis and Design of Wireless Networked Control System Utilizing Adaptive Coded Modulation 被引量:4
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作者 YANG Li GUAN Xin-Ping LONG Cheng-Nian LUO Xiao-Yuan 《自动化学报》 EI CSCD 北大核心 2009年第7期911-918,共8页
关键词 无线网络控制系统 计算机技术 自动化系统 网络条件
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Classification of Multi-User Chirp Modulation Signals Using Wavelet Higher-Order-Statistics Features and Artificial Intelligence Techniques
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作者 Said E. El-Khamy Hend A. Elsayed 《International Journal of Communications, Network and System Sciences》 2012年第9期520-533,共14页
Higher order statistical features have been recently proved to be very efficient in the classification of wideband communications and radar signals with great accuracy. On the other hand, the denoising properties of t... Higher order statistical features have been recently proved to be very efficient in the classification of wideband communications and radar signals with great accuracy. On the other hand, the denoising properties of the wavelet transform make WT an efficient signal processing tool in noisy environments. A novel technique for the classification of multi-user chirp modulation signals is presented in this paper. A combination of the higher order moments and cumulants of the wavelet coefficients as well as the peaks of the bispectrum and its bi-frequencies are proposed as effective features. Different types of artificial intelligence based classifiers and clustering techniques are used to identify the chirp signals of the different users. In particular, neural networks (NN), maximum likelihood (ML), k-nearest neighbor (KNN) and support vector machine (SVMs) classifiers as well as fuzzy c-means (FCM) and fuzzy k-means (FKM) clustering techniques are tested. The Simulation results show that the proposed technique is able to efficiently classify the different chirp signals in additive white Gaussian noise (AWGN) channels with high accuracy. It is shown that the NN classifier outperforms other classifiers. Also, the simulations prove that the classification based on features extracted from wavelet transform results in more accurate results than that using features directly extracted from the chirp signals, especially at low values of signal-to-noise ratios. 展开更多
关键词 Artificial Intelligence TECHNIQUES CLASSIFICATIoN discrete WAVELET Transform Higher order Statistics MULTI-USER CHIRP modulation SIGNALS
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Comparison of performance between bipolar and unipolar double-frequency sinusoidal pulse width modulation in a digitally controlled H-bridge inverter system
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作者 雷博 肖国春 吴旋律 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期277-284,共8页
By deriving the discrete-time models of a digitally controlled H-bridge inverter system modulated by bipolar sinu- soidal pulse width modulation (BSPWM) and unipolar double-frequency sinusoidal pulse width modulati... By deriving the discrete-time models of a digitally controlled H-bridge inverter system modulated by bipolar sinu- soidal pulse width modulation (BSPWM) and unipolar double-frequency sinusoidal pulse width modulation (UDFSPWM) respectively, the performances of the two modulation strategies are analyzed in detail. The circuit parameters, used in this paper, are fixed. When the systems, modulated by BSPWM and UDFSPWM, have the same switching frequency, the stabil- ity boundaries of the two systems are the same. However, when the equivalent switching frequencies of the two systems are the same, the BSPWM modulated system is more stable than the UDFSPWM modulated system. In addition, a convenient method of establishing the discrete-time model of piecewise smooth system is presented. Finally, the analytical results are confirmed by circuit simulations and experimental measurements. 展开更多
关键词 bipolar sinusoidal pulse width modulation (SPWM) unipolar double-frequency SPWM H-bridgeinverter discrete-time model
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A novel DPSS filter optimization scheme to reduce the intrinsic interference of FBMC-QAM systems
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作者 董琪阳 MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第1期68-74,共7页
In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is p... In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is proposed.Firstly,a prototype filter function based on DPSS is designed,since the eigenvalue can be used as an indicator of the energy concentration of DPSS,so a threshold is set,and the sequence with the most concentrated energy is selected under the threshold,that is,the sequence with the eigenvalue higher than the threshold,and the prototype filter function is rewritten as a weighted sum function of multiple eigenvectors.Under the energy constraints of the filter,the relationship between the eigenvectors and the intrinsic interference function is established,and the function problem is transformed into an optimization problem for the weighted coefficients.Through the interior point method,the most suitable weight is found to obtain the minimum intrinsic interference result.Theoretical analysis and simulation results show that compared with the prototype filters such as Type1 and CaseC,the DPSS filter applying the proposed optimization algorithm can effectively suppress the intrinsic interference of the system and obtain a better bit error rate(BER)performance. 展开更多
关键词 filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM) intrinsic interference discrete prolate spheroidal sequences(DPSS) interior point method
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MoS_(2)核壳球上氧掺杂的动力学调制及其电化学分解水效应
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作者 巩飞龙 刘静轩 +2 位作者 刘梦梦 许三魁 李峰 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期256-262,共7页
在氩气气氛中900℃煅烧前驱物MoS_(2)核壳超级球得到MoS_(2)核壳球。在升温速率为20、10、5、2℃·min^(-1)时,MoS_(2)核壳球上氧掺杂量分别从前驱物的23.1%降低到17.6%、10.8%、5.5%、6.2%。结果表明较低的升温速率可以导致更低的... 在氩气气氛中900℃煅烧前驱物MoS_(2)核壳超级球得到MoS_(2)核壳球。在升温速率为20、10、5、2℃·min^(-1)时,MoS_(2)核壳球上氧掺杂量分别从前驱物的23.1%降低到17.6%、10.8%、5.5%、6.2%。结果表明较低的升温速率可以导致更低的氧掺杂量。基于前驱物特殊的准分子超晶格结构,提出了原位阴离子交换反应机理,以深入理解MoS_(2)核壳球上氧掺杂的动力学调制机理。电化学性能研究表明通过调制氧掺杂量可以有效改善MoS_(2)核壳球电化学分解水的性能。 展开更多
关键词 MoS_(2) 核壳球 氧掺杂 动力学调制 电化学性能 分解水
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高速动车组输入输出模块(RIOM)接地方式优化分析
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作者 高盘龙 《中国高新科技》 2024年第1期114-116,共3页
文章对在线运行动车组输入输出模块(RIOM)通信故障较高的问题进行了探究。为了有效降低输入输出模块(RIOM)的故障率,提高在线运行动车组的准点率,首先,对输入输出模块(RIOM)的控制原理进行了分析,对典型故障的输入输出模块(RIOM)进行现... 文章对在线运行动车组输入输出模块(RIOM)通信故障较高的问题进行了探究。为了有效降低输入输出模块(RIOM)的故障率,提高在线运行动车组的准点率,首先,对输入输出模块(RIOM)的控制原理进行了分析,对典型故障的输入输出模块(RIOM)进行现车数据分析、地面脉冲测试,分析故障原因;然后,对输入输出模块(RIOM)在两种接地方式工况下的通信抗干扰能力进行对比分析;最后,通过对比发现输入输出模块(RIOM)接地方式优化后的抗干扰能力明显增强,有效提升输入输出模块(RIOM)的可靠性。 展开更多
关键词 动车组 输入输出模块 抗干扰 接地方式
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基于Watson视觉感知模型的能量调制水印算法 被引量:16
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作者 凌贺飞 卢正鼎 +1 位作者 邹复好 李瑞轩 《软件学报》 EI CSCD 北大核心 2006年第5期1124-1132,共9页
提出一种具有大容量、低复杂性的鲁棒水印算法,主要适合于(但不局限于)JPEG图像和MPEG视频流的实时水印嵌入与检测,因为该算法直接运行于DCT(discretecosinetransform)块数据上.算法主要通过在感知范围内修改DCT块的中低频系数来调制块... 提出一种具有大容量、低复杂性的鲁棒水印算法,主要适合于(但不局限于)JPEG图像和MPEG视频流的实时水印嵌入与检测,因为该算法直接运行于DCT(discretecosinetransform)块数据上.算法主要通过在感知范围内修改DCT块的中低频系数来调制块能量.在能量调制过程中,利用Watson视觉感知模型推导出一条准则,用于限制DCT系数的修改幅度.该系统具有较大的水印容量,可实现在512×512图像中嵌入2048比特.实验表明,算法不仅具有较好的透明性,而且对一些常见的攻击(如高斯噪声、低通滤波、JPEG压缩、增减亮度等)和部分几何攻击(如线性偏移、剪切等)具有较好的鲁棒性. 展开更多
关键词 数字水印 能量调制水印(energy modulATED watermarking简称EMW) Watson视觉感知模型 离散余弦变换(discrete CoSINE transorm简称DCT)
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