In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and pract...In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and practical implications.To address the impact of network communities on target nodes and effectively identify highly influential nodes with strong propagation capabilities,this paper proposes a novel influential spreaders identification algorithm based on density entropy and community structure(DECS).The proposed method initially integrates a community detection algorithm to obtain the community partition results of the networks.It then comprehensively considers the internal and external density entropies and degree centrality of the target node to evaluate its influence.Experimental validation is conducted on eight networks of varying sizes through susceptible–infected–recovered(SIR)propagation experiments and network static attack experiments.The experimental results demonstrate that the proposed method outperforms five other node centrality methods under the same comparative conditions,particularly in terms of information spreading capability,thereby enhancing the accurate identification of critical nodes in networks.展开更多
为探究现代工艺酿造的浓香型白酒不同馏分中各风味组分以及对应酒精度的馏出特性和相关性,以机械化酿造的34个不同馏分的浓香型原酒为研究对象,采用液液萃取-气相色谱-质谱联用(liquid-liquid-extraction gas chromatography-mass,LLE-G...为探究现代工艺酿造的浓香型白酒不同馏分中各风味组分以及对应酒精度的馏出特性和相关性,以机械化酿造的34个不同馏分的浓香型原酒为研究对象,采用液液萃取-气相色谱-质谱联用(liquid-liquid-extraction gas chromatography-mass,LLE-GC-MS)对样品风味物质进行定性定量分析,结合感官品评分析结果,进行了层次聚类热图分析,Pearson相关性分析以及正交偏最小二乘判别分析(orthogonal projections to latent structures-discriminant analysis,OPLS-DA),建立了不同馏分酒精度变化的数学模型:C t=73.373-0.012e 0.007t,其中决定系数以及均方根误差均为0.997,表示模型拟合的效果非常好。通过总结馏出规律,可以很好地把34个馏分分为4个大类,其中馏分0~2为酒头,馏分3~12为头段酒,馏分13~26为中段酒,馏分27~33为酒尾。16种主要风味物质按照相关性分成了A、B两个大类,且2个类别之间存在着显著的负相关,A类物质随着馏分的馏出,含量逐渐降低,B类物质的趋势则完全相反。感官评定结果显示,头段酒的综合评价最好,酯香浓郁,窖香突出,糟味明显,口感谐调,而没有明显的尾味。该研究分别基于风味物质和酒精度建立了不同时间段馏分的分类模型,为浓香型白酒现代工艺的量质摘酒、分段摘酒提供了参考依据。展开更多
In this paper, delay-dependent stability analysis and robust stabilization for uncertain singular time-delay systems are addressed. By using Jensen integral inequality, an improved delay-dependent criterion of admissi...In this paper, delay-dependent stability analysis and robust stabilization for uncertain singular time-delay systems are addressed. By using Jensen integral inequality, an improved delay-dependent criterion of admissibility for singular time-delay systems is proposed in terms of linear matrix inequality （LMI）. Our new proposed criterion is less conservative and the numerical complexity is smaller than the existing ones. Based on this criterion, a state feedback controller is designed to ensure that the uncertain singular time-delay system is admissible. Finally, three numerical examples are employed to illustrate the effectiveness of the proposed method.展开更多
Stability analysis and stabilization for discrete-time singular delay systems are addressed,respectively.Firstly,a sufficient condition for regularity,causality and stability for discrete-time singular delay systems i...Stability analysis and stabilization for discrete-time singular delay systems are addressed,respectively.Firstly,a sufficient condition for regularity,causality and stability for discrete-time singular delay systems is derived.Then,by applying the skill of matrix theory,the state feedback controller is designed to guarantee the closed-loop discrete-time singular delay systems to be regular,casual and stable.Finally,numerical examples are given to demonstrate the effectiveness of the proposed method.展开更多
To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is proposed.This design incorporates an inner rotor with an as...To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is proposed.This design incorporates an inner rotor with an asymmetric sector and a trapezoidal combined N-S pole structure,featuring Halbach arrays for the arrangement of permanent magnets(PMs).The outer rotor PMs adopt a Spoke-type configuration.To optimize the CMG for high output torque and low torque ripple,a sensitivity analysis is conducted to identify key size parameters that significantly influence the optimization objectives.Based on the sensitivity hierarchy of these parameters,a multi-objective optimization analysis is performed using a genetic algorithm(GA)to determine the optimal structural parameter values of the CMG.In addition,a coaxial magnetic gear(CMG)topology with 4 inner and 17 outer pole pairs is adopted,and the parametric model is established.Finally,the electromagnetic properties of the CMG are evaluated using the finite element method.The results indicate a remarkable reduction in torque ripple,specifically by 46.15%.展开更多
Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon...Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon photonics technology,which is compatible with complementary-metal-oxide-semiconductor fabrication processes,provides a low-cost,compact size,lightweight,and low-power-consumption solution.In this work,we demonstrate an optical frequency synthesizer using a fully integrated silicon-based tunable laser.The synthesizer can be self-calibrated by tuning the repetition rate of the internal mode-locked laser.A 20 nm tuning range from 1544 to 1564 nm is achieved with~10−13 frequency instability at 10 s averaging time.Its flexibility and fast reconfigurability are also demonstrated by fine tuning the synthesizer and generating arbitrary specified patterns over time-frequency coordinates.This work promotes the frequency stability of silicon-based integrated tunable lasers and paves the way toward chip-scale lowcost optical frequency synthesizers.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61803264)。
文摘In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and practical implications.To address the impact of network communities on target nodes and effectively identify highly influential nodes with strong propagation capabilities,this paper proposes a novel influential spreaders identification algorithm based on density entropy and community structure(DECS).The proposed method initially integrates a community detection algorithm to obtain the community partition results of the networks.It then comprehensively considers the internal and external density entropies and degree centrality of the target node to evaluate its influence.Experimental validation is conducted on eight networks of varying sizes through susceptible–infected–recovered(SIR)propagation experiments and network static attack experiments.The experimental results demonstrate that the proposed method outperforms five other node centrality methods under the same comparative conditions,particularly in terms of information spreading capability,thereby enhancing the accurate identification of critical nodes in networks.
文摘为探究现代工艺酿造的浓香型白酒不同馏分中各风味组分以及对应酒精度的馏出特性和相关性,以机械化酿造的34个不同馏分的浓香型原酒为研究对象,采用液液萃取-气相色谱-质谱联用(liquid-liquid-extraction gas chromatography-mass,LLE-GC-MS)对样品风味物质进行定性定量分析,结合感官品评分析结果,进行了层次聚类热图分析,Pearson相关性分析以及正交偏最小二乘判别分析(orthogonal projections to latent structures-discriminant analysis,OPLS-DA),建立了不同馏分酒精度变化的数学模型:C t=73.373-0.012e 0.007t,其中决定系数以及均方根误差均为0.997,表示模型拟合的效果非常好。通过总结馏出规律,可以很好地把34个馏分分为4个大类,其中馏分0~2为酒头,馏分3~12为头段酒,馏分13~26为中段酒,馏分27~33为酒尾。16种主要风味物质按照相关性分成了A、B两个大类,且2个类别之间存在着显著的负相关,A类物质随着馏分的馏出,含量逐渐降低,B类物质的趋势则完全相反。感官评定结果显示,头段酒的综合评价最好,酯香浓郁,窖香突出,糟味明显,口感谐调,而没有明显的尾味。该研究分别基于风味物质和酒精度建立了不同时间段馏分的分类模型,为浓香型白酒现代工艺的量质摘酒、分段摘酒提供了参考依据。
基金supported by National Natural Science Foundation of China (No.60904009,No.60974004)
文摘In this paper, delay-dependent stability analysis and robust stabilization for uncertain singular time-delay systems are addressed. By using Jensen integral inequality, an improved delay-dependent criterion of admissibility for singular time-delay systems is proposed in terms of linear matrix inequality （LMI）. Our new proposed criterion is less conservative and the numerical complexity is smaller than the existing ones. Based on this criterion, a state feedback controller is designed to ensure that the uncertain singular time-delay system is admissible. Finally, three numerical examples are employed to illustrate the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China (6090400960974004)
文摘Stability analysis and stabilization for discrete-time singular delay systems are addressed,respectively.Firstly,a sufficient condition for regularity,causality and stability for discrete-time singular delay systems is derived.Then,by applying the skill of matrix theory,the state feedback controller is designed to guarantee the closed-loop discrete-time singular delay systems to be regular,casual and stable.Finally,numerical examples are given to demonstrate the effectiveness of the proposed method.
文摘To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is proposed.This design incorporates an inner rotor with an asymmetric sector and a trapezoidal combined N-S pole structure,featuring Halbach arrays for the arrangement of permanent magnets(PMs).The outer rotor PMs adopt a Spoke-type configuration.To optimize the CMG for high output torque and low torque ripple,a sensitivity analysis is conducted to identify key size parameters that significantly influence the optimization objectives.Based on the sensitivity hierarchy of these parameters,a multi-objective optimization analysis is performed using a genetic algorithm(GA)to determine the optimal structural parameter values of the CMG.In addition,a coaxial magnetic gear(CMG)topology with 4 inner and 17 outer pole pairs is adopted,and the parametric model is established.Finally,the electromagnetic properties of the CMG are evaluated using the finite element method.The results indicate a remarkable reduction in torque ripple,specifically by 46.15%.
基金financial support by the Defense Advanced Research Projects Agency(DARPA)Direct On-Chip Digital Optical Synthesizer(DODOS)project(HR0011-15-C-0056,program manager:Dr.Gordon Keeler)the Deutsche Forschungsgemeinschaft through Priority Program SPP-1221,DFG 18-17 PACE+1 种基金the Deutsches Elektronen Synchrotron-DESYsupported by a National Science Scholarship(NSS)from the Agency for Science,Technology and Research(A*STAR),Singapore.
文摘Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon photonics technology,which is compatible with complementary-metal-oxide-semiconductor fabrication processes,provides a low-cost,compact size,lightweight,and low-power-consumption solution.In this work,we demonstrate an optical frequency synthesizer using a fully integrated silicon-based tunable laser.The synthesizer can be self-calibrated by tuning the repetition rate of the internal mode-locked laser.A 20 nm tuning range from 1544 to 1564 nm is achieved with~10−13 frequency instability at 10 s averaging time.Its flexibility and fast reconfigurability are also demonstrated by fine tuning the synthesizer and generating arbitrary specified patterns over time-frequency coordinates.This work promotes the frequency stability of silicon-based integrated tunable lasers and paves the way toward chip-scale lowcost optical frequency synthesizers.
