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Recursive Projected Filter Algorithm with Binary-Valued Observations

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Journal of systems Science & Complexity 2024年第5期37卷 1832-1860页

作者： ZHANG Xiaoyan WANG Ying XUE Wenchao ZHAO Yanlong Key Laboratory of systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper focuses on the state estimate for a class of systems with both process noise and measurement noise under binary-valued observations, in which the Gaussian assumption on the predicted density of the state is not required. A recursive projected filter algorithm with time-varying thresholds is constructed to estimate the state under binary-valued observations. The time-varying thresholds are designed as the prediction value of the measurement, which can provide more information about the system state. The convergence property is established with some suitable stability,boundedness and observability conditions. In particular, the estimation error between state and estimate is proved to be asymptotically bounded in the mean-square sense, whose upper bound is related to the variance of process noise. Finally, the theoretical results are demonstrated via numerical examples of first-order and high-order systems.

关键词： Binary-valued observations convergence recursive filter time-varying thresholds

Bioinspired synthesis of cochlearol B and ganocin A

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Chinese Chemical Letters 2024年第7期35卷 242-246页

作者： Zhenhao Wang Yuliang Tang Ruyu Li Shuai Tian Yu Tang Dehai Li Key Laboratory of marine Drugs Chinese Ministry of Education/Sanya Oceanographic institute Ocean University of ChinaQingdao 266003/Sanya 572025China Laboratory for marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China marine Biomedical Research institute of Qingdao Ocean University of ChinaQingdao 266071China

Described here is a divergent,biosynthetically inspired synthesis of cochlearol B and ganocin *** steps of the synthesis include the chromene unit construction through a biomimetic acid-catalyzed[4+2]ring cyclization.A photochemical[2+2]cycloaddition was featured to construct the cyclobutane core of cochlearol *** skeletal rearrangements of cochlearol B afforded ganocin A,that one of them was Lewis acid mediated epoxide rearrangement and another was DDQ induced cyclobutane formed tetrahydrofuran *** described syntheses not only achieved these natural products in an efficient manner,but also provided insight into the biosynthetic relationship between the two different skeletons.

关键词： Biomimetic rearrangement Avarane skeleton Cascade reactions Lewis acid Total synthesis

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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing

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Acta Oceanologica Sinica 2024年第3期43卷 66-86页

作者： Lina Cai Jie Yin Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China Zhejiang marine Fisheries Research institute Zhejiang Ocean UniversityZhoushan 316004China

Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture *** methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental *** fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 *** the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in *** results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture *** for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open *** water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the *** fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world.

关键词： mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis

Temperate Stutzerimonas Phage Encoding Toxin-Antitoxin System Genes Represents a Novel Genus

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Journal of Ocean University of China 2024年第4期23卷 1087-1101页

作者： ZHANG Hong GUO Ruizhe GAO Chen ZHENG Kaiyang XIONG Yao DONG Yue LIU Yundan WANG Ziyue CHEN Ying WANG Hongmin SHAO Hongbing SUNG Yeong Yik MOK Wen Jye WONG Li Lian MCMINN Andrew WANG Min LIANG Yantao College of marine Life Sciences Institute of Evolution and Marine BiodiversityMOE Laboratory of Evolution and Marine BiodiversityFrontiers Science Center for Deep Ocean Multispheres and Earth SystemCenter for Ocean Carbon NeutralityOcean University of ChinaQingdao 266003China UMT-OUC Joint Center for marine Studies Qingdao 266003China institute of marine Biotechnology Universiti Malaysia Terengganu21030 Kuala TerengganuMalaysia institute for marine and Antarctic Studies University of TasmaniaHobartTAS 7001Australia Haide College Ocean University of ChinaQingdao 266100China The Affiliated Hospital of Qingdao University Qingdao 266001China

Stutzerimonas have been extensively studied due to their remarkable metabolic and physiological ***,research on its phages is currently *** this study,we isolated a novel double-stranded DNA(dsDNA)phage,vB_SstM-PG1,from the marine environment that infects Stutzerimonas stutzeri *** dsDNA genome is 37204 bp long with a G/C content of 64.14%and encodes 54 open reading *** phage possesses a tail packaging structure that is different from known Stutzerimonas stutzeri phages and exhibits structural protein characteristics similar to those of temperate *** addition,two genes of toxin-antitoxin system,including YdaS_antitoxin and HEPN_SAV_6107,were found in the vB_SstM-PG1 genome and play important roles in regulating host growth and *** phylogenetic tree and comparative genomic analysis,it has been determined that vB_SstM-PG1 is not closely related to any phages previously identified in the GenBank ***,it has a connection with enigmatic,uncultured ***,the vB_SstM-PG1 virus exhibits an average nucleotide identity of over 70%with six uncultivated viruses identified in the IMG/VR v4 *** significant finding has resulted in the identification of a novel viral genus known as Metabovirus.

关键词： Stutzerimonas vB_SstM-PG1 Metabovirus temperate phage genomic and phylogenetic analysis

Responses of Nutrients to the Precipitation Variation and Land Use in Subtropical Monsoonal Small Mountainous Rivers:A Case Study of Baixi Watershed

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Journal of Ocean University of China 2024年第2期23卷 383-391页

作者： TIAN Yuan GAO Fei CAO Ke LV Shenghua DUAN Xiaoyong YIN Ping Qingdao institute of marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266237China Laboratory for marine Geology Laoshan LaboratoryQingdao 266237China

Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and *** order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry *** concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),*** by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle *** rainstorms during the Meiyu period in the watershed caused the pulse runoff in the *** maximum daily runoff reached 70 times that before *** maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,*** view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.

关键词： small mountainous river uneven precipitation rainstorm pulse runoff nitrogen and phosphorus

Recent progress in MnBi2nTe3n+1 intrinsic magnetic topological insulators: crystal growth, magnetism and chemical disorder

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National Science Review 2024年第2期11卷 65-80页

作者： Chaowei Hu Tiema Qian Ni Ni Department of Physics and Astronomy and California Nano systems institute University of California-Los Angeles

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators,etc. To date, the MnBi2nTe3n+1family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

关键词： MnBi2Te4 magnetic topological insulator magnetism tuning antiferromagnetism ferromagnetism pressure chemical doping

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： Xing Chen Yong-gang Lu institute of systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Hybrid Strategy of Partitioned and Monolithic Methods for Solving Strongly Coupled Analysis of Inverse and Direct Piezoelectric and Circuit Coupling

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1371-1386页

作者： Daisuke Ishihara Syunnosuke Nozaki Tomoya Niho Naoto Takayama Department of Intelligent and Control systems Kyushu Institute of TechnologyFukuokaJapan

The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy *** strongly coupled analysis methods based on direct numerical modeling for this phenomenon can be classified into partitioned or monolithic *** formulation has its advantages and disadvantages,and the choice depends on the characteristics of each coupled *** study proposes a new option:a coupled analysis strategy that combines the best features of the existing formulations,namely,the hybrid partitioned-monolithic *** analysis of inverse piezoelectricity and the monolithic analysis of direct piezoelectric and circuit interaction are strongly coupled using a partitioned iterative hierarchical *** a typical benchmark problem of a piezoelectric energy harvester,this research compares the results from the proposed method to those from the conventional strongly coupled partitioned iterative method,discussing the accuracy,stability,and computational *** proposed hybrid concept is effective for coupled multi-physics problems,including various coupling conditions.

关键词： Structure-piezoelectric-circuit interaction energy harvesting partitioned method monolithic method hybrid method

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying LI Xin ZHAO Yanlong ZHANG Ji-Feng Key Laboratory of systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.