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Initial costates derived by near-optimal reference sequence and least-squares method

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Chinese Journal of Aeronautics 2024年第5期37卷 377-391页

作者： Shaozhao LU Yao zhang quan HU School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper,we present a novel initial costates solver for initializing time-optimal trajectory problems in relative motion with continuous low *** proposed solver consists of two primary components:training a Multilayer Perceptron(MLP)for generating reference sequence and Time of Flight(TOF)to the target,and deriving a system of linear algebraic equations for obtaining the initial *** overcome the challenge of generating training samples for the MLP,the backward generation method is proposed to obtain five different training *** training database and sample form are determined by analyzing the input and output correlation using the Pearson correlation *** best-performing MLP is obtained by analyzing the training results with various hyper-parameter combinations.A reference sequence starting from the initial states is obtained by integrating forward with the near-optimal control vector from the output of ***,a system of linear algebraic equations for estimating the initial costates is derived using the reference sequence and the necessary conditions for *** results demonstrate that the proposed initial costates solver improves the convergence ratio and reduce the function calls of the shooting ***,Monte-Carlo simulation illustrates that the initial costates solver is applicable to different initial velocities,demonstrating excellent generalization ability.

关键词： Relative motion Expanding training database Multilayer perceptron Initial costates Least-squares method

A novel algorithm for satellite data transmission

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Science China(Technological Sciences) 2009年第5期52卷 1429-1434页

作者： zhang ShouJuan ZHOU quan National Key Laboratory of Space Microwave Technology China Academy of Space TechnologyXi’an 710000China

For remote sensing satellite data transmission,a novel algorithm is proposed in this *** integrates different type feature descriptors into multistage *** the first level,the dynamic clustering algorithm is *** the second level,the improved support vector machines algorithm demonstrates its *** the third level,the shape matrices similarity comparison algorithm shows its excellent *** single child recognizers are connected in series,but they are independent of each *** which are not recognized correctly by the lower level recognizers are then put into the higher level *** results show that the multistage recognition algorithm improves the accuracy greatly with higher level feature descriptors and higher level *** algorithm may offer a new methodology for high speed satellite data transmission.

关键词： satellite data transmission multistage recognition dynamic clustering support vector machines shape matrices similarity comparison

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液相色谱质谱联用测定纸张中丙烯酰胺含量

中国造纸 2025年第1期44卷 174-178,61页

作者：刘洋沈臻煌孙文刚林婉婷张权蔡慧张蒙黄举中国制浆造纸研究院有限公司北京100102 中轻(晋江)卫生用品研究有限公司福建晋江362200

本研究建立了液相色谱串联多级质谱(LC-MS/MS)测定纸张中丙烯酰胺含量的方法,分析了样品提取条件对检测结果的影响,并对丙烯酰胺在纸和纸板之间的迁移规律进行了初步探究。本研究以水为提取液,将样品超声提取30 min后,采用LC-MS/MS的多... 详细信息

本研究建立了液相色谱串联多级质谱(LC-MS/MS)测定纸张中丙烯酰胺含量的方法,分析了样品提取条件对检测结果的影响,并对丙烯酰胺在纸和纸板之间的迁移规律进行了初步探究。本研究以水为提取液,将样品超声提取30 min后,采用LC-MS/MS的多反应离子监测(MRM)进行样品检测,内标法定量。结果表明,超声提取可以有效提高纸张中丙烯酰胺的溶出速率;同一样品重复测定的相对标准偏差均<5%,3个添加水平的平均回收率在93.13%~99.89%,表明该方法具有较好的重复性和准确度。此外,丙烯酰胺在特定条件下能够在接触的纸和纸板之间发生迁移,生活用纸企业应对此现象予以关注。

关键词：液相色谱串联多级质谱丙烯酰胺迁移

醋酸烯醇酯与硫氰酸钠电化学条件下α-硫氰化反应

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有机化学 2025年第01期45卷 189-195页

作者：张金鹏钱宇亮宁梦妍蔡童钦苏张竞瑶于泉荣良策徐州医科大学公共卫生学院江苏省生物数据挖掘与医疗健康转化工程研究中心江苏师范大学化学与材料科学学院

报道了在电化学条件下醋酸烯醇酯与硫氰酸钠发生硫氰化反应.研究表明,由不同类型酮衍生的醋酸烯醇酯都可以应用于本反应体系,而硫氰酸钠则是优秀的硫氰基源试剂.本研究还具有操作简单、反应条件温和及底物范围广等优点,为获得α-硫氰基... 详细信息

报道了在电化学条件下醋酸烯醇酯与硫氰酸钠发生硫氰化反应.研究表明,由不同类型酮衍生的醋酸烯醇酯都可以应用于本反应体系,而硫氰酸钠则是优秀的硫氰基源试剂.本研究还具有操作简单、反应条件温和及底物范围广等优点,为获得α-硫氰基酮衍生物提供了有效的合成途径.

关键词：电化学醋酸烯醇酯 α-硫氰基化硫氰酸钠

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Ubiquitination in diabetes and its complications:A perspective from bibliometrics

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World Journal of Diabetes 2025年第1期16卷 187-203页

作者： Li-Yuan Xiong Wei Zhao Fa-quan Hu Xue-Mei Zhou Yu-Jiao Zheng College of Traditional Chinese Medicine Anhui University of Chinese MedicineHefei 230012Anhui ProvinceChina

BACKGROUND Diabetes has a substantial impact on public health,highlighting the need for novel ***,an intracellular protein modification process,is emerging as a promising strategy for regulating pathological *** hypothesize that ubiquitination plays a critical role in the development and progression of diabetes and its complications,and that understanding these mechanisms can lead to new therapeutic *** To uncover the research trends and advances in diabetes ubiquitination and its complications,we conducted a bibliometric *** Studies on ubiquitination in diabetes mellitus and its complications were retrieved from the Web of Science Core *** mapping analysis was conducted using the CiteSpace *** We gathered 791 articles published over the past 23 years,focusing on ubiquitination in diabetes and its associated *** articles originated from 54 countries and 386 institutions,with China as the leading *** Jiao Tong University has the highest number of publications in this *** most prominent authors contributing to this research area include Wei-Hua zhang,with zhang Y being the most frequently cited ***,The Journal of Biological Chemistry is noted as the most cited in this *** predominant keywords included expression,activation,oxidative stress,phosphorylation,ubiquitination,degradation,and insulin *** The role of ubiquitination in diabetes and its complications,such as diabetic nephropathy and cardiomyopathy,is a key research ***,these areas require further investigations.

关键词： Diabetes mellitus Ubiquitination Bibliometric analysis CiteSpace Research trends

Visual interpretability for deep learning：a survey

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Frontiers of Information Technology & Electronic Engineering 2018年第1期19卷 27-39页

作者： quan-shi zhang Song-chun ZHU University of California Los Angeles California 90095 USA

This paper reviews recent studies in understanding neural-network representations and learning neural networks with interpretable/disentangled middle-layer *** deep neural networks have exhibited superior performance in various tasks,interpretability is always Achilles' heel of deep neural *** present,deep neural networks obtain high discrimination power at the cost of a low interpretability of their black-box *** believe that high model interpretability may help people break several bottlenecks of deep learning,e.g.,learning from a few annotations,learning via human–computer communications at the semantic level,and semantically debugging network *** focus on convolutional neural networks(CNNs),and revisit the visualization of CNN representations,methods of diagnosing representations of pre-trained CNNs,approaches for disentangling pre-trained CNN representations,learning of CNNs with disentangled representations,and middle-to-end learning based on model ***,we discuss prospective trends in explainable artificial intelligence.

关键词： Artificial intelligence Deep learning Interpretable model

New calculations indicate that 90% of flowering plant species are animal-pollinated

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National Science Review 2023年第10期10卷 17-19页

作者： Ze-Yu Tong Ling-Yun Wu Hui-Hui Feng Meng zhang W.Scott Armbruster Susanne S.Renner shuang-quan Huang Institute of Evolution and Ecology School of Life Sciences Central China Normal University Faculty of Resources and Environmental Science Hubei University School of Biological Sciences University of Portsmouth Institute of Arctic Biology University of Alaska Fairbanks Department of Biology Washington University

The services of animal pollinators that deliver compatible pollen to receptive stigmas are essential for the reproduction of many flowering plants [1,2].The maintenance of plant-pollinator interactions,therefore,is the basis for the function and sustainability of healthy *** this reason, there has been widespread concern over the past two decades about the global decline in pollinators and the effects of this loss on pollination services for both wild plants and crops [3,4].

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The Fundamental Plane of GRBs

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Research in Astronomy and Astrophysics 2023年第12期23卷 221-229页

作者： Xu zhang quan-Gui Gao Department of Physics Yuxi Normal UniversityYuxi 653100China Key Laboratory of Astroparticle Physics of Yunnan Province Kunming 650091China

Gamma-ray bursts(GRBs)exhibit powerful radiation and relativistic jets similar to ***,the central engine of GRBs remains *** this paper,we use the fundamental plane to analyze a sample of GRBs with measured *** extend,over~12 orders of magnitude,the correlation analysis and fundamental plane with a sample of X-ray binaries,active galactic nuclei(AGNs)including blazars,and brightest cluster *** fundamental plane of our de-beamed sample,with a measured mass(logL_(R)=(0.60±0.03)logL_(X)+(0.78±0.02)logM+7.23±0.95),closely aligns with the findings of previous work on *** finding suggests that GRBs adhere to the fundamental plane of AGNs and supports the theory proposed in previous work that the central engine of GRBs may be black *** observation provides a plausible explanation for the striking similarities between GRBs and AGNs.

关键词： (stars:)gamma-ray burst general-radiation mechanisms general-galaxies active

Reasoning and predicting POMDP planning complexity via covering numbers

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Frontiers of Computer Science 2016年第4期10卷 726-740页

作者： Zongzhang zhang Qiming FU Xiaofang zhang quan LIU School of Computer Science and Technology Soochow University Suzhou 215000 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210000 China School of Electronic and Information Engineering Suzhou University of Science and Technology Suzhou 215000 China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun 130012 China

Partially observable Markov decision processes （POMDPs） provide a rich mathematical framework for planning tasks in partially observable stochastic environments. The notion of the covering number, a metric of capturing the search space size of a POMDP planning problem, has been proposed as a complexity measure of approximate POMDP planning. Existing theoretical results are based on POMDPs with finite and discrete state spaces and measured in the l1- metric space. When considering heuristics, they are assumed to be always admissible. This paper extends the theoretical results on the covering numbers of different search spaces, including the newly defined space reachable under inadmissible heuristics, to the ln-metric spaces. We provide a simple but scalable algorithm for estimating covering numbers. Experimentally, we provide estimated covering numbers of the search spaces reachable by following different policies on several benchmark problems, and analyze their abilities to predict the runtime of POMDP planning algorithms.

关键词： POMDP planning complexity theory covering number search space