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Review on bio-inspired polarized skylight navigation

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Chinese Journal of Aeronautics 2023年第9期36卷 14-37页

作者： fang KONG yingjing guo Jianhua ZHANG Xiaojing FAN Xiaohan guo School of Electrical and Automation Engineering Shandong University of Science and TechnologyQingdao 266590China School of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China Qingdao Intelligence Ocean Technology Co. Ltd.Qingdao 266590China School of Information Science and Engineering Qingdao School of Shandong UniversityQingdao 266237China

In this review, the research progress of bio-inspired polarized skylight navigation is evaluated from the perspectives of theoretical basis, information detection, sensor design, and navigation realization. First, the theory for characterizing the polarization mode of the skylight was introduced. Second, using sunlight, moonlight, and ocean as backgrounds, the measurement results of skylight polarization distribution under different weather conditions are described to compare the variation patterns. Third, the development history and research outcomes of bionic polarization navigation sensor for polarized skylight detection and navigation information calculation are categorized into two types, namely non-imaging and imaging types. In precision measurement, the non-imaging type is higher than the imaging type, and the accuracy that it can reach is ± 0.1° of navigation accuracy without drift error. Fourth, two polarized skylight orientation algorithms,E-vector-based method and Solar Meridian-Anti Solar Meridian(SM-ASM)-based method are summarized. Fifth, this review details the combined application of polarized skylight navigation sensors and Inertial Navigation System(INS), Global Navigation Satellite System(GNSS), Vision,Simultaneous Localization and Mapping(SLAM), and other navigation systems. The yaw and trajectory accuracy can be increased by about 40% compared to classical navigation system in complex outdoor environments. Finally, the future development trends of polarization navigation are presented.

关键词： Navigation Polarization Polarized skylight navigation sensors Polarized skylight navigation system Skylight polarization pattern

Optimal Dividend and Dynamic Reinsurance Strategies with Capital Injections and Proportional Costs

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Acta Mathematicae Applicatae Sinica 2012年第3期28卷 505-524页

作者： yi-dong WU Jun-yi guo School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China School of Economics Yunnan UniversityKunming 650091China

We consider an optimization problem of an insurance company in the diffusion setting, which controls the dividends payout as well as the capital injections. To maximize the cumulative expected discounted dividends minus the penalized discounted capital injections until the ruin time, there is a possibility of （cheap or non-cheap） proportional reinsurance. We solve the control problems by constructing two categories of suboptimal models, one without capital injections and one with no bankruptcy by capital injection. Then we derive the explicit solutions for the value function and totally characterize the optimal strategies. Particularly, for cheap reinsurance, they axe the same as those in the model of no bankruptcy.

关键词： proportional reinsurance non-cheap optimal dividend capital injections

A parameter formula connecting PID and ADRC

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Science China(Information Sciences) 2020年第9期63卷 175-187页

作者： Sheng ZHONG yi HUANG Lei guo Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper presents a parameter formula connecting the well-known proportional-integralderivative(PID) control and the active disturbance rejection control(ADRC). On the one hand, this formula gives a quantitative lower bound to the bandwidth of the extended state observer(ESO) used in ADRC,implying that the ESO is not necessarily of high gain. On the other hand, enlightened by the design of ADRC, a new PID tuning rule is provided, which can guarantee both strong robustness and nice tracking performance of the closed-loop systems under the PID control. Moreover, it is proved that the ESO can be rewritten as a suitable linear combination of the three terms in PID, which can give a better estimate for the system uncertainty than the single integral term in the PID controller. Theoretical results are verified also by simulations in the paper.

关键词： nonlinear uncertain systems proportional-integral-derivative PID active disturbance rejection control ADRC extended state observer ESO

Potassium and phosphorus transport and signaling in plants

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Journal of Integrative Plant Biology 2021年第1期63卷 34-52页

作者： yi Wang yi-fang Chen Wei-Hua Wu State Key Laboratory of Plant Physiology and Biochemistry(SKLPPB) College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Nitrogen(N), potassium(K), and phosphorus(P) are essential macronutrients for plant growth and development, and their availability affects crop yield. Compared with N, the relatively low availability of K and P in soils limits crop production and thus threatens food security and agricultural sustainability. Improvement of plant nutrient utilization efficiency provides a potential route to overcome the effects of K and P deficiencies. Investigation of the molecular mechanisms underlying how plants sense, absorb, transport, and use K and P is an important prerequisite to improve crop nutrient utilization efficiency. In this review, we summarize current understanding of K and P transport and signaling in plants, mainly taking Arabidopsis thaliana and rice(Oryza sativa) as examples. We also discuss the mechanisms coordinating transport of N and K, as well as P and N.

关键词： phosphorus plant nutrition potassium transport signaling

Impact of alkyl chain branching positions on molecular packing and electron transport of dimeric perylenediimide derivatives

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Journal of Energy Chemistry 2019年第8期28卷 138-143,I0006页

作者： Yuan guo Guangchao Han Yuanping yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of SciencesBeijing 100190 China University of Chinese Academy Sciences Beijing 100049 China

Side chains play a critical role in tuning intermolecular interaction and charge transport in organic semiconductors. Here, we have systematically investigated the impact of branching positions of the alkyl side chains on the molecular packing and electron transport properties of a series of bay-linked dimeric perylenediimide(PDI) derivatives by atomistic molecular dynamics simulations in combination with charge transfer rate theory and kinetic Monte Carlo simulations. The results show that despite of different branching positions of the alkyl chains,π–π stacking is effectively inhibited for all the dimeric PDI derivatives. As the branching position moves away from the PDI backbone, the appearance of the alkyl atoms around the PDI backbone will first decrease and then increase. Correspondingly, the short contacts between the PDI moieties are first enhanced and then reduced. In particular, when the branching position is at the third carbon atom, the intermolecular connectivity becomes the most effective and the electron mobility is significantly increased by 2 times.

关键词： Molecular packing Electron mobility Branching position Perylenediimide

Genetic algorithm aided density functional theory simulations unravel the kinetic nature of Au(100) in catalytic CO oxidation

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Chinese Chemical Letters 2019年第6期30卷 1346-1350页

作者： yi fang Xueqing Gong Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Instiute of Industrial CatalysisSchool of Chemistry Molecular EngineeringEast China University of Science and Technology

Heterogeneous catalysis is of tremendous importance to modern industries. Exposed atoms of heterogeneous catalysts are heavily involved in surface processes such as the adsorption, activation, diffusion and reaction of substrate molecules. Surfaces of metal or metal oxide based catalysts are usually taken as hard templates that only undergo limited relaxation during catalytic reactions, especially in theoretical simulations. In this work, by using genetic algorithm (GA) aided density functional theory (DFT) calculations, we studied the surface processes involved in CO oxidation on the Au(100) surface. The use of GA greatly improves the capacity of DFT calculations in locating the potential energy surface (PES) of the surface reactions, and surprisingly, it has been found that the Au(100) surface can undergo drastic reconstruction under the influence of O adsorption and the adapted partially oxidized Au surface exhibits unique activities for subsequent adsorptions and reactions. This work depicts the kinetic nature of the Au (100) surface in its catalyzed reactions and also significantly expands our understanding of how surface atoms act in heterogeneous catalysis.

关键词： Gold catalysts Genetic algorithm Density functional theory Potential energy surface Surface reconstruction

An Encoding-Decoding Framework Based on CNN for circ RNA-RBP Binding Sites Prediction

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Chinese Journal of Electronics 2024年第1期33卷 256-263页

作者： Yajing guo Xiujuan LEI yi PAN School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Department of Computer Science Georgia State University

Predicting RNA binding protein(RBP) binding sites on circular RNAs(circ RNAs) is a fundamental step to understand their interaction mechanism. Numerous computational methods are developed to solve this problem, but they cannot fully learn the features. Therefore, we propose circ-CNNED, a convolutional neural network(CNN)-based encoding and decoding framework. We first adopt two encoding methods to obtain two original matrices. We preprocess them using CNN before fusion. To capture the feature dependencies, we utilize temporal convolutional network(TCN) and CNN to construct encoding and decoding blocks, respectively. Then we introduce global expectation pooling to learn latent information and enhance the robustness of circ-CNNED. We perform circ-CNNED across 37 datasets to evaluate its effect. The comparison and ablation experiments demonstrate that our method is superior. In addition, motif enrichment analysis on four datasets helps us to explore the reason for performance improvement of circ-CNNED.

关键词： Proteins RNA Neural networks Encoding Robustness Decoding Convolutional neural networks

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Fixed-Time Leader-Following Formation Control of Fully-Actuated Underwater Vehicles Without Velocity Measurements

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Journal of Systems Science & Complexity 2022年第2期35卷 559-585页

作者： GAO Zhenyu ZHANG yi guo Ge School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China

This paper is concerned with formation control of fully-actuated underwater vehicles(FUVs),focusing on improving system convergence speed and overcoming velocity measurement *** employing the fixed-time control theory and command filtering technique,a full state feedback formation algorithm is proposed,which makes the follower track the leader in a given time with all signals in the system globally practically stabilized in fixed *** avoid degraded control performance due to inaccurate velocity measurement,a fixed-time convergent observer is designed to estimate the velocity of *** the authors give an observer-based fixed-time control method,with which acceptable formation performance can be achieved in fixed time without velocity *** effectiveness and performance of the proposed method are demonstrated by numerical simulations.

关键词： Fixed-time control formation control fully-actuated underwater vehicles(FUVs) state feedback control velocity observer

Neuroprotective effects of chaperone-mediated autophagy in neurodegenerative diseases

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Neural Regeneration Research 2024年第6期19卷 1291-1298页

作者： Qi Jia Jin Li Xiaofeng guo yi Li You Wu Yuliang Peng Zongping fang Xijing Zhang Department of Anesthesiology and Perioperative Medicine and Department of Intensive Care Unit Xijing HospitalThe Fourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Critical Care Medicine Air Force Medical CenterBeijingChina Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People’s HospitalSchool of MedicineTongji UniversityShanghaiChina

Chaperone-mediated autophagy is one of three types of autophagy and is characterized by the selective degradation of ***-mediated autophagy contributes to energy balance and helps maintain cellular homeostasis,while providing nutrients and support for cell ***-mediated autophagy activity can be detected in almost all cells,including *** to the extreme sensitivity of neurons to their environmental changes,maintaining neuronal homeostasis is critical for neuronal growth and ***-mediated autophagy dysfunction is closely related to central nervous system *** has been shown that neuronal damage and cell death are accompanied by chaperone-mediated autophagy *** certain conditions,regulation of chaperone-mediated autophagy activity attenuates *** this paper,we review the changes in chaperone-mediated autophagy in neurodegenerative diseases,brain injury,glioma,and autoimmune *** also summarize the most recent research progress on chaperone-mediated autophagy regulation and discuss the potential of chaperone-mediated autophagy as a therapeutic target for central nervous system diseases.

关键词： chaperone-mediated autophagy neurodegenerative disease neuronal homeostasis neuroprotection