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A new SINS/GPS sensor fusion scheme for UAV localization problem using nonlinear SVSF with covariance derivation and an adaptive boundary layer

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Chinese Journal of Aeronautics 2016年第2期29卷 424-440页

作者： Fariz Outamazirt fu Li lin Yan Abdelkrim Nemra School of Automation Science and Electrical Engineering Beihang University School of Control and Automation Ecole Militaire Polytechnique

The state estimation strategy using the smooth variable structure filter （SVSF） is based on the variable structure and sliding mode concepts. As presented in its standard form with a fixed boundary layer limit, the value of the boundary layer width is not precisely known at each step and may be selected based on a priori knowledge. The boundary layer width reflects the level of uncertainty in the model parameters and disturbance characteristics, where large values of the boundary layer width lead to robustness without optimality and small values of the boundary layer width provide optimality with poor robustness. As a solution and to overcome these limitations, an adaptive smoothing boundary layer is required to achieve greater robustness and suitable accuracy. This adapted value of the boundary layer width is obtained by minimizing the trace of the a posteriori covariance matrix. In this paper, the proposed new approach will be considered as another alternative to the extended Kalman filters （EKF）, nonlinear H∞ and standard SVSF-based data fusion techniques for the autonomous airborne navigation and self-localization problem. This alternative is based on strapdown inertial navigation system （SINS） and GPS data using the nonlinear SVSF with a covariance derivation and adaptive boundary layer width. furthermore, the full mathematical model of the SINS/GPS navigation system considering the unmanned aerial vehicle （UAV） position, velocity and Euler angle as well as gyro and accelerometer biases will be used in this paper to estimate the airborne position and velocity with better accuracy.

关键词： Adaptive smoothing bound-ary layer Autonomous airborne navi-gation GPS Smooth variable structurefilter (SVSF) Strapdown inertial naviga-tion system (SINS)

Synthesis and enhanced visible-light responsive of C,N,S-tridoped TiO_2 hollow spheres

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Journal of Environmental Sciences 2013年第10期25卷 2150-2156页

作者： Xiaoxia lin Degang fu lingyun Hao Zhen Ding School of Material Engineering Jinling Institute of Technology State Key Laboratory of Bioelectronics Southeast University Jiangsu Centers for Disease Control and Prevention

C,N,S-tridoped TiO2 hollow spheres （labeled as C,N,S-THs） were synthesized using carbon spheres as template and C,N,S-tridoped TiO2 nanoparticles as building blocks. The structure and physicochemical properties of the catalysts were characterized by X- ray diffraction （XRD）, scanning electron microscopy （SEM）, UV-Vis diffuse reflectance spectrum （DRS）, N2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy （XPS） and Photoluminescence emission spectroscopy （PL）. The results showed that the hollow spheres had average diameter of about 200 nm and the shell thickness was about 20 nm. The tridoped TiO2 hollow spheres exhibited strong absorption in the visible-light region. C,N,S-tridoped could narrow the band gap of the THs by mixing the orbit O 2p with C 2p, N 2p and S 3p orbits and shift its optical response from ultraviolet （UV） to the visible-light region. PL analysis indicated that the electron-hole recombination rate of TiO2 hollow spheres had been effectively inhibited when doped with C, N and S elements. The photocatalytic activities of the samples were evaluated for the degradation of X-3B （Reactive Brilliant Red dye, C.I. Reactive Red 2） aqueous solution under visible-light （λ 〉 420 nm） irradiation. It was found that the C,N,S-tridoped TiO2 hollow spheres indicated higher photocatalytic activity than commercial P25 and the undoped counterpart photocatalyst.

关键词： titania C,N,S-tridoped hollow spheres visible-light photocatalysis

Securing STAR-FC-RIS empowered integrated sensing and multiuser communications against target eavesdropping

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Science China(Information Sciences) 2024年第11期67卷 335-346页

作者： Shuying lin Yulong ZOU fu XIAO Bin LI School of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications School of Computer Science Nanjing University of Posts and Telecommunications Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications

This paper investigates a simultaneous-transmitting-and-reflecting fully-connected reconfigurable intelligent surface(STAR-FC-RIS) empowered integrated sensing and multiuser communications(ISAMC) network, where a dual-functional radar-communication base station detects a malicious radar target nearby and communicates with multiple legitimate users on the other side of the STAR-RIS. We utilize an integrated architecture that combines the fully-connected(FC)-RIS, an emerging type of beyond-diagonal(BD)-RIS, with the time-switching(TS)-STAR-RIS to enhance both the sensing and communications at the cost of possible target intercepting and propose the simultaneous-transmitting-and-reflecting fully-connected RIS(STAR-FCR) schemes to strike a balance between sensing and communications performance. Thereafter, observing the security-reliability performance tradeoff of the downlink ISAMC, we conduct closed-form analyses to compare COPs of round-robin scheduling(RS) and multiuser scheduling(MS) with the aid of a TS-based STAR-FC-RIS. furthermore, we derive closed-form expressions of the sensing outage probability, communications outage probability(COP), and communications intercept probability, where an average of the three probabilities is exploited to obtain an optimized time allocation(OTA) of the *** results verify that the STAR-FCR-MS scheme outperforms the STAR-FCR-RS scheme in terms of sensing reliability and communications security. Moreover, an OTA remarkably enhances the overall performance of the STAR-FCR schemes of ISAMC systems.

关键词： simultaneous-transmitting-and-reflecting reconfigurable intelligent surface (RIS) fully-connected beyond-diagonal RIS integrated sensing and communications multiuser scheduling security

Mean-square exponential stability of stochastic Volterra systems in infinite dimensions

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Science China(Information Sciences) 2024年第10期67卷 298-314页

作者： lin fu Shiguo PENG Feiqi DENG Quanxin ZHU School of Automation Guangdong University of Technology School of Automation Science and Engineering South China University of Technology Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) School of Mathematics and StatisticsHunan Normal University

Over the past decade, the study of stability theory in integro-differential systems has grown significantly owing to their relevance in solving physical and engineering problems, such as viscoelasticity and thermo-viscoelasticity in materials with memory properties. This paper concentrates on a class of infinite-dimensional stochastic integro-differential systems. We establish the well-posedness of the system and identify mild solutions to the system and an abstract stochastic Cauchy problem. This identification is identified by employing a semigroup approach combined with Yosida approximation. We derive sufficient conditions that ensure the mean-square exponential stability of mild solutions to the system boils down to the boundedness of a certain function and a norm estimate for the stochastic part. These conditions are implemented through the semigroup approach and the composition operator method. Illustrative examples are provided and the obtained theoretical results are validated by numerical simulations.

关键词： stochastic integro-differential equations mean-square exponential stability stochastic distributed parameter systems Hardy space composition operators

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Experimental Study of Cavitation Phenomenon in a Centrifugal Blood Pump Induced by the Failure of Inlet Cannula

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 165-170页

作者： lin Zhe RUAN Xiaodong ZOU Jun fu Xin The State Key Lab of Fluid Power Transmission and Control Zhejiang University

Cavitation of centrifugal blood pump is a serious problem accompany with the blocking failure of short inlet cannula. However, hardly any work has been seen in published literature on this complex cavitation phenomenon caused by the coupling effect of inlet cannula blocking and pumps suction. Even for cavitation studies on ordinary centrifugal pumps, similar researches on this issue are rare. In this paper, the roles of throttling, rotation speed and fluid viscosity on bubble inception and intensity in a centrifugal blood pump are studied, on the basis of experimental observations. An adjustable throttle valve installed just upstream blood pump inlet is used to simulate the throttling effect of the narrowed inlet cannula. The rotation speed is adjusted from 2 600 r/rain to 3 200 r/min. Glycerin water solutions are used to investigate the influences of kinetic viscosity. Bubbles are recorded with a high-speed video camera. Direct observation shows that different from cavitation in industrial centrifugal pumps, gas nuclei appears at the nearby of vane leading edges while throttling is light, then moves upstream to the joint position of inlet pipe and pump with the closing of the valve. It＇s found that the critical inlet pressure, obtained when bubbles are first observed, decreases linearly with viscosity and the slope is independent with rotation speeds; the critical inlet pressure and the inlet extreme pressure which is obtained when the throttle valve is nearly closed, fall linearly with rotation speed respectively and the relative pressure between them is independent with rotation speed and fluid viscosity. This paper studies experimentally on cavitation in centrifugal blood pump that caused by the failure of assembled short inlet cannula, which mav beneficial the desima of centrifugal blood Dumo with inlet cannula.

关键词： centrifugal blood pump cavitation viscosity cannula diameter rotation speed

Serotonylation: A novel histone H3 marker

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Signal Transduction and Targeted Therapy 2019年第1期4卷 548-549页

作者： lin fu lingqiang Zhang Institute of Chronic Disease Qingdao Municipal HospitalQingdao University266000 QingdaoChina State Key Laboratory of Proteomics National Center of Protein Sciences(Beijing)Beijing Institute of Lifeomics100850 BeijingChina

A recent study by Farrelly,*** *** in Nature showed that the serotonylation of glutamine at the Q5 site in histone H3 promotes the recruitment of TFIID in collaboration with adjacent H3K4 trimethylation *** posttranslational modifications(PTMs)of histones are associated with diverse biological processes through dynamically modulating chromatin structure and the transcriptional activity of genes *** regulations are an integral part of brain functions ranging from the development of the nervous system beyond basic neurological functions to higher-order cognitive processes 3.

关键词： roton system trimethyl

The Progress of the Global Tobacco Cessation Strategies

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China CDC weekly 2023年第21期5卷 475-478页

作者： Dongbo fu lin Xiao Health Promotion Department World Health OrganizationGenevaSwitzerland Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina

The tobacco epidemic is one of the biggest public health threats the world has ever faced,killing more than 8 million people a year,mainly through noncommunicable diseases(NCDs)(1).World Health Organization(WHO)set nine voluntary global targets for NCDs to be attained by 2025,including a 30%relative reduction in prevalence of current tobacco use by 2025(2),which requires a strong commitment by governments to strengthen the national health system responses and to take action against the leading risk factors for NCDs including tobacco use,the single most preventable cause of *** to strengthening full implementation of the WHO Framework Convention on Tobacco Control(WHO FCTC)is a crucial component of action by governments.

关键词： action tobacco

Covalent electron density analysis and surface energy calculation of gold with the empirical electron surface model

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 676-682页

作者： Bao-qin fu Zhi-lin Li Wei Liu College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Laboratory of Advanced Materials Department of Material Science and Engineering Tsinghua University Beijing 100084 China

Based on the empirical electron surface model （EESM）,the covalent electron density of dangling bonds （CEDDB） was calculated for various crystal planes of gold,and the surface energy was calculated *** results show that CEDDB has a great influence on the surface energy of various index surfaces and the anisotropy of the *** calculated surface energy is in agreement with experimental and other theoretical *** calculated surface energy of the close-packed （111） surface has the lowest surface energy,which agrees with the theoretical ***,it is found that the spatial distribution of covalent bonds has a great influence on the surface energy of various index ***,CEDDB should be a suitable parameter to describe and quantify the dangling bonds and surface energy of various crystal surfaces.

关键词： surface energy dangling bonds covalent bonds electron density gold

Deep learning tomographic reconstruction through hierarchical decomposition of domain transforms

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 365-377页

作者： lin fu Bruno De Man GE Research NY 12309 NiskayunaUSA

Deep learning(DL)has shown unprecedented performance for many image analysis and image enhancement ***,solving large-scale inverse problems like tomographic reconstruction remains challenging for *** problems involve non-local and space-variant integral transforms between the input and output domains,for which no efficient neural network models are readily available.A prior attempt to solve tomographic reconstruction problems with supervised learning relied on a brute-force fully connected network and only allowed reconstruction with a 128^(4)system matrix *** cannot practically scale to realistic data sizes such as 512^(4)and 512^(6)for three-dimensional *** we present a novel framework to solve such problems with DL by casting the original problem as a continuum of intermediate representations between the input and output *** original problem is broken down into a sequence of simpler transformations that can be well mapped onto an efficient hierarchical network architecture,with exponentially fewer parameters than a fully connected network would *** applied the approach to computed tomography(CT)image reconstruction for a 5124 system matrix *** work introduces a new kind of data-driven DL solver for full-size CT reconstruction without relying on the structure of direct(analytical)or iterative(numerical)inversion *** work presents a feasibility demonstration of full-scale learnt reconstruction,whereas more developments will be needed to demonstrate superiority relative to traditional reconstruction *** proposed approach is also extendable to other imaging problems such as emission and magnetic resonance *** broadly,hierarchical DL opens the door to a new class of solvers for general inverse problems,which could potentially lead to improved signal-to-noise ratio,spatial resolution and computational efficiency in various areas.

关键词： Computed tomography Image reconstruction Deep learning Hierarchical