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Adaptive nonlinear Kalman filters based on credibility theory with noise correlation

Chinese Journal of Aeronautics 2024年第6期37卷 232-243页

作者： Quanbo ge Zihao song Bingtao ZHU Bingjun ZHANG School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing 210044China School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 330013China School of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China School of Electronic and Information Engineering Tongji UniversityShanghai 200092China

To solve the divergence problem and overcome the difficulty in guaranteeing filtering accuracy during estimation of the process noise covariance or the measurement noise covariance with traditional new information-based nonlinear filtering methods,we design a new method for estimating noise statistical characteristics of nonlinear systems based on the credibility Kalman Filter(KF)theory considering noise *** method first extends credibility to the Unscented Kalman Filter(UKF)and Extended Kalman Filter(EKF)based on the credibility ***,an optimization model for nonlinear credibility under noise related conditions is established considering noise correlation.A combination of filtering smoothing and credibility iteration formula is used to improve the real-time performance of the nonlinear adaptive credibility KF algorithm,further expanding its application scenarios,and the derivation process of the formula theory is ***,the performance of the nonlinear credibility filtering algorithm is simulated and analyzed from multiple perspectives,and a comparative analysis conducted on specific experimental *** simulation and experimental results show that the proposed credibility EKF and credibility UKF algorithms can estimate the noise covariance more accurately and effectively with lower average estimation time than traditional methods,indicating that the proposed algorithm has stable estimation performance and good real-time performance.

关键词： Kalman filter Extended Kalman Filter(EKF) Unscented Kalman Filter(UKF) Credibility Noise correlation

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Effect of confinement on the three-phase equilibrium of water-oil-CO_(2)mixtures in nanopores

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Petroleum Science 2022年第1期19卷 203-210页

作者： Yi-Lei song Shao-Hua Gu Zhao-Jie song Zhuo-ya Zhang Xu-ya Chang Jia Guo State Key Laboratory of Petroleum Resources and Prospecting and Unconventional Petroleum Research Institute China University of Petroleum-BeijingBeijing102249China Sinopec Petroleum Exploration and Production Research Institute Beijing100083China

Accurate characterization of fluid phase behavior is an important aspect of CO_(2) enhanced shale oil *** far,however,there has been little discussion about the nanopore confinement effect,including adsorption and capillarity on the phase equilibrium of water-oil-CO_(2) *** this study,an improved three-phase flash algorithm is proposed for calculating the phase behavior of water-oil-gas mixture on the basis of an extended Young-Laplace equation and a newly developed fugacity calculation *** fugacity model can consider the effect of water-oil-gas adsorption on phase equilibrium.A water-Bakken oil-CO_(2) mixture is utilized to verify the accuracy of the flash algorithm and investigate the confinement *** show that the confinement effect promotes the transfer of all components in the vapor phase to other phases,while the transfer of water,CO_(2),and lighter hydrocarbons is more *** leads to a large decrease,a large increase,and a small increase in the mole fraction of the vapor,oleic,and aqueous phases,*** the confinement effect is considered,the density difference of vaporoleic phases decreases,and the interfacial tension of vapor-oleic phases decreases;however,the density difference of vapor-aqueous phases increases,the interfacial tension of vapor-aqueous phases still decreases.

关键词： Three-phase behavior Water-oil-CO_(2)mixtures Nanopore confinement CO_(2)enhanced oil recovery Shale reservoirs

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DRPS:efficient disk-resident parameter servers for distributed machine learning

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Frontiers of Computer Science 2022年第4期16卷 79-90页

作者： Zhen song Yu Gu Zhigang Wang ge Yu School of Computer Science and Engineering Northeastern UniversityShenyang110819China College of Information Science and Engineering Ocean University of ChinaQingdao266100China

Parameter server(PS)as the state-of-the-art distributed framework for large-scale iterative machine learning tasks has been extensively ***,existing PS-based systems often depend on memory *** memory constraints,machine learning(ML)developers cannot train large-scale ML models in their rather small local ***,renting large-scale cloud servers is always economically infeasible for research teams and small *** this paper,we propose a disk-resident parameter server system named DRPS,which reduces the hardware requirement of large-scale machine learning tasks by storing high dimensional models on *** further improve the performance of DRPS,we build an efficient index structure for parameters to reduce the disk I/O *** on this index structure,we propose a novel multi-objective partitioning algorithm for the ***,a flexible workerselection parallel model of computation(WSP)is proposed to strike a right balance between the problem of inconsistent parameter versions(staleness)and that of inconsistent execution progresses(straggler).Extensive experiments on many typical machine learning applications with real and synthetic datasets validate the effectiveness of DRPS.

关键词： parameter servers machine learning disk resident parallel model

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Cache-Conscious Index Mechanism for Main-Memory Databases

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 309-312页

作者： SUN Li-mei song Bao-yan YU ya-xin LI Fang-fang YU ge School of Information Science and Engineering Northeastern University Shenyang 110004 Liaoning China

Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^＋-tree are shown to outperform conventional main memory indices such as the AVL-tree and the T-tree. This paper proposes a cacheconscious version of the T-tree, CST-tree, defined according to the cache-conscious definition. To separate the keys within a node into two parts, the CST-tree can gain higher cache hit ratio.

关键词： index structure main memory database real time application cache-conscious T-tree indexing CST-tree indexing

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Updated thoughts on SARS-CoV-2 and coronavirus therapies,fighting and surviving

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BIOCELL 2020年第2期44卷 127-135页

作者： WENJUAN LI ge song Department of Immunology and Microbiology The Scripps Research InstituteLa JollaUSA

From late December 2019 a new human-adapted coronavirus,SARS-CoV-2,was observed and isolated in clustered patients in Wuhan,*** has been proved to be able to transmit human-to-human and cause pneumonia,leading to about 2%*** genome characteristics,immune responses and related potential treatments,such as chemical drugs,serum transfusion and vaccines including DNA vaccines,are discussed in this review for a brief summary.

关键词： SARS-CoV2 Cellular mechanism Therapies Antibody Vaccine

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Vibration signal-based chatter identification for milling of thin-walled structure

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Chinese Journal of Aeronautics 2022年第1期35卷 204-214页

作者： Wenping MOU Shaowei ZHU Zhenxi JIANG ge song NC Machining Plant Chengdu Aircraft Industrial(Group)Co.LtdChengdu 610092China

In high speed milling aeronautical part,tool condition monitoring(TCM)is very important,because it is prone to get a chatter owing to the low stiffness of thin-walled *** the TCM is key technology for automated *** this paper,aiming to chatter monitoring in thin-walled structure milling,a variational mode decomposition–energy distribution(VMD-ED)method is proposed to improve the identification *** a moving average root mean square–mean value(MARMS-MV)identification method and a variational mode decomposition–energy entropy(VMD-EE)identification method are also *** accuracy and computing time of the three methods are *** vibration signals collected from the spindle and worktable are also *** conducted experimental study shows that,the proposed VMD-ED method offers an identification method for chatter monitoring with greater sensitivity,better stability and less computing time,and mounting the vibration sensor on worktable is better than spindle for a chatter monitoring system.

关键词： Chatter Milling Thin-walled structure Tool condition monitoring Vibration

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The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： yanxi Li Jing Xue Yuejia Ma Ke Ye Xue Zhao Fangliang ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

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德国英语教材价值观呈现研究

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外语学刊 2025年第1期 70-77页

作者：葛囡囡北京外国语大学德语学院北京100089

近年来,教材中的价值观呈现愈加受到教材编写者和使用者的关注。本文以德国英语教材On Track为研究对象,探究其价值观呈现的情况。研究发现:在该教材呈现的德国主流价值观中,最常见的价值观类别是社群关系价值观、个人成长价值观、传统... 详细信息

近年来,教材中的价值观呈现愈加受到教材编写者和使用者的关注。本文以德国英语教材On Track为研究对象,探究其价值观呈现的情况。研究发现:在该教材呈现的德国主流价值观中,最常见的价值观类别是社群关系价值观、个人成长价值观、传统文化价值观和发展观念价值观。价值观呈现方式特点有三,即螺旋复现的价值观主题、追求真实的语言中介板块、以思辨能力为导向的素材选择和练习设计。此外,该教材的价值观呈现模态多样。最后,本文针对我国外语教材编写和教材使用如何助力价值观教育提出建议。

关键词：价值观英语教材德国外语教材呈现方式呈现模态

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Effect of phosphate releasing in activated sludge on phosphorus removal from municipal wastewater

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Journal of Environmental Sciences 2018年第5期30卷 216-223页

作者： Jie ge Xiaoguang Meng Yonghui song Amalia Terracciano Center of Environmental Systems Stevens Institute of Technology State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences

Aluminum and ferric salts are commonly used in municipal wastewater treatment plants（WWPTs） for phosphorus（P） removal. In this study, on-site jar tests were conducted to determine the removal of different P species from the fresh samples in the presence and absence of activated sludge（AS） with different doses of alum, poly-aluminum chloride,and ferric chloride at different p H. The soluble P（SP） concentration in the samples was about 0.63 mg/L. When the mixed liquor containing AS was treated with 8 mg/L of Al, SP could be reduced to 0.13 mg/L, while it was reduced to 0.16 mg/L with only 1 mg/L of Al after sedimentation removal of AS from sample. Chemical analysis determined that AS contained 59.8 mg-P/g-TSS and 43.8 mg-Al/g-TSS and most of the P was associated with the aluminum hydroxide. We discovered that the phosphate in the AS could readily be released from it, which was mainly responsible for ineffective removal of P to low levels in mixed liquor even with very high alum dose. This study provides new insight into the behavior and fate of P in the wastewater treatment plants that use alum to enhance P removal in the final effluent.

关键词： Phosphorus release Coagulation Activated sludge (AS) Wastewater treatment

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Abundance and Community Composition of Ammonia-Oxidizers in Paddy Soil at Different Nitrogen Fertilizer Rates

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Journal of Integrative Agriculture 2014年第4期13卷 870-880页

作者： song ya-na LIN Zhi-min Institute of Biological Technology Fujian Academy of Agricultural Sciences

Ammonia oxidation, the first and rate-limiting step of nitrification, is carried out by both ammonia-oxidizing bacteria （AOB） and ammonia-oxidizing archaea （AOA）. However, the relative importance of AOB and AOA to nitrification in terrestrial ecosystems is not well understood. The aim of this study was to investigate the effect of the nitrogen input amount on abundance and community composition of AOB and AOA in red paddy soil. Soil samples of 10-20 cm （root layer soil） and 0-5 cm （surface soil） depths were taken from a red paddy. Rice in the paddy was fertilized with different rates of N as urea of N1 （75 kg N ha＂ yr-1）, N2 （150 kg N ha~ yrl）, N3 （225 kg N ha1 yrl） and CK （without fertilizers） in 2009, 2010 and 2011. Abundance and community composition of ammonia oxidizers was analyzed by real-time PCR and denaturing gradient gel electrophoresis （DGge） based on amoA （the unit A of ammonia monooxygenase） gene. Archaeal amoA copies in N3 and N2 were significantly （P〈0.05） higher than those in CK and N1 in root layer soil or in surface soil under tillering and heading stages of rice, while the enhancement in bacterial amoA gene copies with increasing of N fertilizer rates only took on in root layer soil. N availability and soil NO3--N content increased but soil NH4＋-N content didn＇t change with increasing of N fertilizer rates. Otherwise, the copy numbers of archaeal amoA gene were higher （P〈0.05） than those of bacterial amoA gene in root lary soil or in surface soil. Redundancy discriminate analysis based on DGge bands showed that there were no obvious differs in composition of AOA or AOB communities in the field among different N fertilizer rates. Results of this study suggested that the abundance of ammonia-oxidizers had active response to N fertilizer rates and the response of AOA was more obvious than that of AOB. Similarity in the community composition of AOA or AOB among different N fertilizer rates indicate that the community composition of ammonia-oxidizers w

关键词： ammonia-oxidizing bacteria ammonia-oxidizing archaea nitrogen fertilizer rates paddy soil

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