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编码协作系统基于最大公约数定理的QC⁃RA码联合构造

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南京邮电大学学报（自然科学版） 2021年第1期41卷 42-50页

作者：付勇峰张顺外南京邮电大学通信与信息工程学院江苏南京210003

准循环重复累积(Quasi⁃Cyclic Repeat Accumulate,QC⁃RA)码具有准循环低密度奇偶校验(Low Density Parity Check,LDPC)码的优点,同时能实现差分编码且为系统码,非常适用于编码协作系统,文中研究采用QC⁃RA码的编码协作系统。首先,提出基... 详细信息

准循环重复累积(Quasi⁃Cyclic Repeat Accumulate,QC⁃RA)码具有准循环低密度奇偶校验(Low Density Parity Check,LDPC)码的优点,同时能实现差分编码且为系统码,非常适用于编码协作系统,文中研究采用QC⁃RA码的编码协作系统。首先,提出基于最大公约数(Greatest Common Divisor,GCD)定理的QC⁃RA码构造方法;然后,进一步基于GCD定理联合构造编码协作系统信源节点与中继节点采用的QC⁃RA码,并从理论上证明基于该联合构造方法得到的编码协作系统QC⁃RA码无girth⁃4、girth⁃6环。仿真结果表明,采用QC⁃RA码的编码协作系统相对于点对点系统具有明显的性能增益;同时,与采用大列重构造QC⁃RA的编码协作相比,采用文中基于GCD定理联合构造的QC⁃RA码的编码协作误码率性能更加优异。

关键词：编码协作准循环重复累积码最大公约数定理联合构造

2,4-二氯-5-氟嘧啶的合成及废液回收处理利用

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化工学报 2015年第5期66卷 1723-1729页

作者：付永丰郭宁云志孙珊珊南京工业大学化学化工学院江苏南京210009 齐鲁工业大学化学与制药工程学院山东济南250353

使用5-氟尿嘧啶(5-fu)和三氯氧磷(POCl3)作为原料、N,N-二甲基苯胺(DMA)作为缚酸剂合成2,4-二氯-5-氟嘧啶,系统研究了5-fu与POCl3的摩尔比、5-fu与DMA的摩尔比、反应温度和反应时间对反应收率的影响,简要阐述该反应机理。反应结束后,向... 详细信息

使用5-氟尿嘧啶(5-fu)和三氯氧磷(POCl3)作为原料、N,N-二甲基苯胺(DMA)作为缚酸剂合成2,4-二氯-5-氟嘧啶,系统研究了5-fu与POCl3的摩尔比、5-fu与DMA的摩尔比、反应温度和反应时间对反应收率的影响,简要阐述该反应机理。反应结束后,向废液中加入Na OH固体对废液进行处理,探讨DMA的回收率和副产物磷酸氢二钠的收率与p H的关系。结果表明,在工艺参数为5-fu与POCl3的摩尔比为1:10、5-fu与DMA的摩尔比为1:1.5、回流温度114℃、回流时间2 h时,2,4-二氯-5-氟嘧啶的收率为92.2%;通过加入Na OH固体将废液p H调至7,DMA的回收率和副产物磷酸氢二钠的收率都为最大值。

关键词： 5-氟尿嘧啶缚酸剂合成废水回收水合物

A Tutorial on Quantized Feedback Control

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 5-17页

作者： Minyue fu IEEE the School of System Design and Intelligent Manufacturing Shenzhen Key Laboratory of Control Theory and Intelligent Systems and Centre for Control Science and TechnologySouthern University of Science and TechnologyShenzhen 518055China

In this tutorial paper, we explore the field of quantized feedback control, which has gained significant attention due to the growing prevalence of networked control systems. These systems require the transmission of feedback information, such as measurements and control signals, over digital networks, presenting novel challenges in estimation and control design. Our examination encompasses various topics, including the minimal information needed for effective feedback control, the design of quantizers, strategies for quantized control design and estimation,achieving consensus control with quantized data, and the pursuit of high-precision tracking using quantized measurements.

关键词： Consensus control high-precision control networked control quantized estimation quantized feedback control robust control

湘东锡田燕山期A型花岗岩黑云母矿物化学特征及其成岩成矿意义

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地球科学（中国地质大学学报） 2017年第10期42卷 1647-1657页

作者：周云梁新权蔡永丰付伟桂林理工大学广西隐伏金属矿产勘查重点实验室广西桂林541004 广西有色金属隐伏矿床勘查及材料开发协同创新中心广西桂林541004 中国科学院广州地球化学研究所广东广州510640

黑云母的化学组成特征对揭示花岗岩的源区特征、形成环境、后期热液作用以及成矿元素富集特征具有重要的指示意义.对与锡田钨锡多金属矿床成矿作用密切相关的锡田燕山早期花岗岩黑云母和长石成分进行了系统的电子探针分析.分析结果表明... 详细信息

黑云母的化学组成特征对揭示花岗岩的源区特征、形成环境、后期热液作用以及成矿元素富集特征具有重要的指示意义.对与锡田钨锡多金属矿床成矿作用密切相关的锡田燕山早期花岗岩黑云母和长石成分进行了系统的电子探针分析.分析结果表明,黑云母具有富铁贫镁、高铝低钠的特征,其MgO和FeOT含量分别为0.12%~1.35%和15.47%~23.24%,类似于高铁黑云母;其含铁指数Fe/(Fe+Mg)较高,集中在0.87~0.99,属于铁叶云母;其长石主要以正长石和钠长石为主.这些特征暗示了寄主岩石源区以壳源为主.结合相关区域地质资料,表明锡田燕山早期花岗质岩浆具有较高的温度和较低的氧逸度.黑云母具有高的含铁指数、较高的结晶温度和低的氧逸度等特征均有利于锡成矿,可以作为勘探锡矿的标志之一.综合分析认为,在锡田花岗质岩浆演化过程中,岩浆结晶期后分异出的流体趋向于向富锡的方向演化,是锡田多金属矿床成矿流体的重要来源.

关键词：黑云母矿物成分成岩成矿花岗岩锡田钨锡多金属矿床地球化学

Dynamics of 2×2 matrix non-Hermitian quantum systems on Bloch sphere

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Communications in Theoretical Physics 2024年第4期76卷 66-71页

作者： Libin fu Graduate School of China Academy of Engineering Physics Beijing 100193China

By casting evolution to the Bloch sphere, the dynamics of 2 × 2 matrix non-Hermitian systems are investigated in detail. This investigation reveals that there are four kinds of dynamical modes for such systems. The different modes are classified by different kinds of fixed points, namely,the elliptic point, spiral point, critical node, and degenerate point. The Hermitian systems and the unbroken PT non-Hermitian cases belong to the category with elliptic points. The degenerate point just corresponds to the systems with exceptional point(EP). The topological properties of the fixed point are also discussed. It is interesting that the topological charge for the degenerate point is two, while the others are one.

关键词： non-Hermitian quantum system two-level system dynamics on the Bloch sphere PT-symmetry fixed points

Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in Shaanxi Province,China

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Chinese Geographical Science 2024年第3期34卷 401-419页

作者： fu Shaowu fu Mengyu QIU Menglong Center for Land Resource Research in Northwest China Shaanxi Normal UniversityXi’an 710119China

One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem *** many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely *** view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this *** analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling *** show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to *** service lag was identified as the dominant unbalanced development *** the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess *** coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious ***,cropland intensification practices in the area should be optimized to enhance this coordination *** upward trend was also observed in the coupling coordination degree from2000 to *** withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern *** 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern *** clustering characteristics are mainly attributed to the environmental

关键词： cropland intensification agroecosystem services balance analysis coupling coordination degree Loess Plateau,China

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基于模型性能评估的递推PLS建模及应用

化工学报 2014年第12期65卷 4875-4882页

作者：徐欧官陈祥华傅永峰李丽娟浙江工业大学之江学院浙江杭州310032 南京工业大学自动化与电气工程学院江苏南京210009

为了降低递推部分最小二乘(RPLS)建模方法的模型校正频率,开发了一种基于模型性能评估的RPLS(MPA-RPLS)模型。首先,根据过程的初始特性,自动生成模型的置信限,以均方根误差(RMSEP)为性能指标,评估模型性能;依据模型性能的评估结果,选择... 详细信息

为了降低递推部分最小二乘(RPLS)建模方法的模型校正频率,开发了一种基于模型性能评估的RPLS(MPA-RPLS)模型。首先,根据过程的初始特性,自动生成模型的置信限,以均方根误差(RMSEP)为性能指标,评估模型性能;依据模型性能的评估结果,选择性地启动模型校正和置信限校正。然后,引入滑动平均滤波器消除过程变量中的噪声,探讨噪声对模型性能的影响程度。最后,将MPA-RPLS模型应用于一个化学反应过程——C8芳烃临氢异构化过程,基于大量工业数据,进行仿真验证。仿真结果表明:本文开发的模型仅以微小的精度损失换取了模型计算效率的大幅提高(即模型校正频率大幅下降);滑动平均滤波器可有效地处理变量的噪声,改善模型的预测精度。

关键词：递推PLS 模型性能评估滑动平均滤波器化学反应过程模拟

Floating Waste Discovery by Request via Object-Centric Learning

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Computers, Materials & Continua 2024年第7期80卷 1407-1424页

作者： Bingfei fu School of Computer Science Fudan UniversityShanghai200438China

Discovering floating wastes,especially bottles on water,is a crucial research problem in environmental ***,real-world applications often face challenges such as interference from irrelevant objects and the high cost associated with data ***,devising algorithms capable of accurately localizing specific objects within a scene in scenarios where annotated data is limited remains a formidable *** solve this problem,this paper proposes an object discovery by request problem setting and a corresponding algorithmic *** proposed problem setting aims to identify specified objects in scenes,and the associated algorithmic framework comprises pseudo data generation and object discovery by request ***-data generation generates images resembling natural scenes through various data augmentation rules,using a small number of object samples and scene *** network structure of object discovery by request utilizes the pre-trained Vision Transformer(ViT)model as the backbone,employs object-centric methods to learn the latent representations of foreground objects,and applies patch-level reconstruction constraints to the *** the validation phase,we use the generated pseudo datasets as training sets and evaluate the performance of our model on the original test *** have proved that our method achieves state-of-the-art performance on Unmanned Aerial Vehicles-Bottle Detection(UAV-BD)dataset and self-constructed dataset Bottle,especially in multi-object scenarios.

关键词： Unsupervised object discovery object-centric learning pseudo data generation real-world object discovery by request

LMR-CBT: learning modality-fused representations with CB-Transformer for multimodal emotion recognition from unaligned multimodal sequences

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Frontiers of Computer Science 2024年第4期18卷 39-47页

作者： Ziwang fu Feng LIU Qing XU Xiangling fu Jiayin QI School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Trustworthy Distributed Computing and Service(BUPT) Beijing 100876China Shanghai International School of Chief Technology Officer East China Normal UniversityShanghai 200062China School of Computer Science and Technology East China Normal UniversityShanghai 200062China School of Cyberspace Security Guangzhou UniversityGuangdong 510006China

Learning modality-fused representations and processing unaligned multimodal sequences are meaningful and challenging in multimodal emotion *** approaches use directional pairwise attention or a message hub to fuse language,visual,and audio ***,these fusion methods are often quadratic in complexity with respect to the modal sequence length,bring redundant information and are not *** this paper,we propose an efficient neural network to learn modality-fused representations with CB-Transformer(LMR-CBT)for multimodal emotion recognition from unaligned multi-modal ***,we first perform feature extraction for the three modalities respectively to obtain the local structure of the ***,we design an innovative asymmetric transformer with cross-modal blocks(CB-Transformer)that enables complementary learning of different modalities,mainly divided into local temporal learning,cross-modal feature fusion and global self-attention *** addition,we splice the fused features with the original features to classify the emotions of the ***,we conduct word-aligned and unaligned experiments on three challenging datasets,IEMOCAP,CMU-MOSI,and *** experimental results show the superiority and efficiency of our proposed method in both *** with the mainstream methods,our approach reaches the state-of-the-art with a minimum number of parameters.

关键词： modality-fused representations cross-model blocks multimodal emotion recognition unaligned multimodal sequences computational affection