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Manipulating the measured uncertainty under Lee-Yang dephasing channels through local PT-symmetric operations

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Frontiers of physics 2023年第5期18卷 311-320页

作者： Ling-Yu Yao Li-Juan Li xue-ke song Liu Ye Dong Wang School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

Uncertainty relation lies at the heart of quantum physics,which is one of the fundamental characteristics of quantum *** the advent of quantum information theory,entropic uncertainty relation was proposed,which plays an important and irreplaceable role in quantum information *** this work,we attempt to observe dynamics of entropic uncertainty in the presence of quantum memory under two different types of Lee-Yang dephasing *** is interesting to find that the dephasing channels have a negative effect on decreasing the uncertainty and the analogous partition function is anti-correlated with the *** addition,we here propose an effective strategy to manipulate the uncertainty of interest of the subsystem by performing a parity-time symmetric(PT-symmetric)*** is worth noting that the uncertainty of measurement will be reduced to a certain extent by properly modulating the PT-symmetric operations under the considered *** this sense,we argue that our explorations offer insight into dynamics of entropic uncertainty in typical Lee-Yang dephasing channels,and might be beneficial to quantum measurement estimation in practical quantum systems.

关键词： entropic uncertainty relation quantum correlation PT-symmetric operation

Fast achievement of quantum state transfer and distributed quantum entanglement by dressed states

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Chinese Physics B 2020年第5期29卷 107-118页

作者： Liang Tian Li-Li Sun Xiao-Yu Zhu xue-ke song Lei-Lei Yan Er-Jun Liang Shi-Lei Su Mang Feng School of Physics Zhengzhou UniversityZhengzhou 450001China College of Physics Tonghua Normal UniversityTonghua 134000China College of Science Henan University of EngineeringZhengzhou 451191China School of Physics and Material Science Anhui UniversityHefei 230601China State key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China

We propose schemes to realize quantum state transfer and prepare quantum entanglement in coupled cavity and cavity-fiber-cavity systems,respectively,by using the dressed state *** first give the expression of pulses shape by using dressed states and then find a group of Gaussian pulses that are easy to realize in experiment to replace the ideal pulses by curve *** also study the influence of some parameters fluctuation,atomic spontaneous emission,and photon leakage on *** results show that our schemes have good *** the atoms are trapped in different cavities,it is easy to perform different operations on different *** proposed schemes have the potential applications in dressed states for distributed quantum information processing tasks.

关键词： quantum state transfer dressed state method distributed quantum information processing

Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： xue-Qing Wang Cheng song Ting Lei key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Improved Multistage Wiener Filters in Nonhomogeneous Clutter Environments

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Journal of Electronic Science and Technology of China 2008年第1期6卷 75-78页

作者： Bin Tang xue-Gang Wang ke-song Chen School ot ElectromcEngineering University of Electronic Science and Technology of ChinaChengdu 610054 China

A new method combining space-time preprocessing with multistage Wiener filters（STPMWF）is proposed to improve the performance of space-time adaptive processing（STAP）in nonhomogeneous clutter *** new scheme only requires the data from the primary range bin,thus it can suppress discrete interferers efficiently,without calculating the inverse of covariance *** to the original MWF approach,the proposed scheme can be regarded as practical solutions for robust and effective STAP of nonhomogeneous radar *** theoretical analysis shows that our STPMWF is simple in implementation and fast in *** numeric results by using simulated data exhibit a good agreement with the proposed theory.

关键词： Airborne early warning (AEW) radar,clutter suppress multistage Wiener filters (MWF),nonhomogeneous clutter space-time adaptive processing(STAP).

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： xue-Qin Li Lu-Kai song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Mutations in the SARS-CoV-2 spike receptor binding domain and their delicate balance between ACE2 affinity and antibody evasion

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Protein & Cell 2024年第6期15卷 403-418页

作者： song xue Yuru Han Fan Wu Qiao Wang key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) Shanghai Institute of Infectious Disease and BiosecurityShanghai Frontiers Science Center of Pathogenic Microorganisms and InfectionSchool of Basic Medical SciencesShanghai Medical CollegeFudan UniversityShanghai 200032China

Intensive selection pressure constrains the evolutionary trajectory of SARS-CoV-2 genomes and results in various novel variants with distinct mutation *** mutations,particularly those within the receptor binding domain(RBD)of SARS-CoV-2 spike(S)protein,lead to the functional alteration in both receptor engagement and monoclonal antibody(mAb)***,we review the data of the RBD point mutations possessed by major SARS-CoV-2 variants and discuss their individual effects on ACE2 affinity and immune *** single amino acid substitutions within RBD epitopes crucial for the antibody evasion capacity may conversely weaken ACE2 binding ***,this weakened effect could be largely compensated by specific epistatic mutations,such as N501Y,thus maintaining the overall ACE2 affinity for the spike protein of all major *** predominant direction of SARS-CoV-2 evolution lies neither in promoting ACE2 affinity nor evading mAb neutralization but in maintaining a delicate balance between these two ***,this review interprets how RBD mutations efficiently resist antibody neutralization and meanwhile how the affinity between ACE2 and spike protein is maintained,emphasizing the significance of comprehensive assessment of spike mutations.

关键词： ACE2 affinity maintained

Comparison of models to predict air infiltration rate of buildings with different surrounding environments

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Building Simulation 2024年第6期17卷 1007-1021页

作者： Shu Zheng Xiujiao song Lin Duanmu Yu xue Xudong Yang Department of Building Science Tsinghua UniversityBeijing100084China School of Civil Engineering Dalian University of TechnologyDalian116024China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan030032China

The air infiltration rate of buildings strongly influences indoor environment and energy *** this study,several traditional methods for determining the air infiltration rate were compared,and their accuracy in different scenarios was ***,a method combining computational flow dynamics(CFD)with the Swami and Chandra(S-C)model was developed to predict the influence of the surrounding environment on the air infiltration *** buildings in Dalian,China,were selected:one with a simple surrounding environment and the other with a complex surrounding environment;their air infiltration rates were *** test results were used to validate the accuracy of the air infiltration rate solution models in different urban *** the building with a simple environment,the difference between the simulation and experimental results was 0.86%–22.52%.For the building with a complex environment,this difference ranged from 17.42%to 159.28%.We found that most traditional models provide accurate results for buildings with simple surrounding and that the simulation results widely vary for buildings with complex *** results of the method of combining CFD with the S-C model were more accurate,and the relative error between the simulation and test results was 10.61%.The results indicate that the environment around the building should be fully considered when calculating the air infiltration *** results of this study can guide the application of methods of determining air infiltration rate.

关键词： air infiltration rate models CFD simulation building surrounding air infiltration rate test

Design and Experimental Verification of a Roll Control Strategy for Large Wingspan Flapping-Wing Aerial Vehicle

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Journal of Bionic Engineering 2024年第4期21卷 1644-1661页

作者： Rui Meng Bifeng song Jianlin Xuan Xiaojun Yang Dong xue School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518057China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang215400China

Most flapping-wing aircraft wings use a single degree of freedom to generate lift and thrust by flapping up and down,while relying on the tail control surfaces to manage ***,these aircraft have certain limitations,such as poor accuracy in attitude control and inadequate roll control *** paper presents a design for an active torsional mechanism at the wing's trailing edge,which enables differential variations in the pitch angle of the left and right wings during *** simple mechanical form significantly enhances the aircraft's roll control *** experimental verification of this mechanism was conducted in a wind tunnel using the RoboEagle flapping-wing aerial vehicle that we *** study investigated the effects of the control strategy on lift,thrust,and roll moment during flapping ***,the impact of roll control on roll moment was examined under various wind speeds,flapping frequencies,angles of attack,and wing ***,several rolling maneuver flight tests were performed to evaluate the agility of RoboEagle,utilizing both the elevon control strategy and the new roll control *** results demonstrated that the new roll control strategy effectively enhances the roll control capability,thereby improving the attitude control capabilities of the flapping-wing aircraft in complex wind field *** conclusion is supported by a comparison of the control time,maximum roll angle,average roll angular velocity,and other relevant parameters between the two control strategies under identical roll control input.

关键词： Roll control Bio-inspired Roll moment Flapping wing aerial vehicle

Increasing operational stability of journal bearing in hydraulic suspension micro-pump by herringbone grooved structure

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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： HONG Tao XING GuanYing ZUO HuaiYu xue song LUO XiaoBing State key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump