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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

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

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电去离子水软化技术的实验研究

工业水处理 2007年第12期27卷 52-55页

作者：王建友王世昌傅学起南开大学环境科学与工程学院天津300071 天津大学化学工程研究所天津300072

阐述了电去离子水软化技术的原理,并对超滤/电去离子(UF/EDI)工艺用于常规自来水脱硬,制备常低压工业锅炉软化水进行了实验研究。EDI水软化过程的特征曲线表明,该过程工况与传统电渗析过程相似,但分离效率显著提高。对于电导率627μS/cm... 详细信息

阐述了电去离子水软化技术的原理,并对超滤/电去离子(UF/EDI)工艺用于常规自来水脱硬,制备常低压工业锅炉软化水进行了实验研究。EDI水软化过程的特征曲线表明,该过程工况与传统电渗析过程相似,但分离效率显著提高。对于电导率627μS/cm的UF原水,实验条件下EDI软化过程的总脱盐率达到65%,而Ca2+、Mg2+的去除率则分别达到99.7%和99.97%,产品水硬度<0.05 mg/L。研究表明,EDI工艺有望发展成为继纳滤之后的又一高效膜软化水新技术。

关键词：电去离子填充床电渗析水软化

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

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电去离子技术处理低浓度重金属废水研究进展

化工进展 2006年第11期25卷 1270-1275页

作者：卢会霞闫博王建友傅学起南开大学环境科学与工程学院天津300071

阐述了电去离子(EDI)过程的去离子原理,综述了EDI技术处理低浓度重金属废水过程中,离子交换介质与离子交换膜的应用,以及床层结构、膜堆构造和工艺流程的最新进展,分析了现有几种传质模型的优缺点,提出了目前存在的问题和今后发展的方向。

关键词：电去离子重金属废水离子交换

基于拉伸分子动力学模拟的黄嘌呤氧化酶抑制剂解离途径的理论研究

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高等学校化学学报 2021年第3期42卷 758-766页

作者：齐人睿李明昊常浩付学奇高波韩葳葳韩璐李婉南吉林大学分子酶学工程教育部重点实验室生命科学学院长春130012 吉林省特医食品生物科技有限公司长春130052

采用拉伸分子动力学模拟的方法研究了黄嘌呤氧化酶(Xanthine oxidase,XO)抑制剂别嘌呤醇(Allopuri⁃nol)和葛根素(Puerarin)从XO离去通道解离的动态过程.分子对接结果表明,别嘌呤醇和葛根素均结合在XO的钼蝶呤中心(Molybdopterin,Mo-pt)... 详细信息

采用拉伸分子动力学模拟的方法研究了黄嘌呤氧化酶(Xanthine oxidase,XO)抑制剂别嘌呤醇(Allopuri⁃nol)和葛根素(Puerarin)从XO离去通道解离的动态过程.分子对接结果表明,别嘌呤醇和葛根素均结合在XO的钼蝶呤中心(Molybdopterin,Mo-pt);丙氨酸扫描的结果显示,Val789,Arg880,Phe911,Phe914和Val1081在XO与抑制剂的结合中起到非常重要的作用.拉伸分子动力学模拟结果显示,相比于葛根素,别嘌呤醇需要更大的外力和更长的时间才能从XO中解离,拉伸过程中Arg880,Phe1009,Thr1010,Val1011和Ala1079均对维持2种复合物的结构稳定起到重要作用,Phe649和Phe1013在抑制剂解离过程中起到门控的作用,His875起到阻碍抑制剂解离的作用.

关键词：黄嘌呤氧化酶别嘌呤醇葛根素痛风拉伸分子动力学模拟

New speckle pattern interferometry for precise in situ deformation measurements

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Chinese Optics Letters 2024年第1期22卷 34-40页

作者：章如月 Yu fu 缪泓 CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

A new electronic speckle pattern interferometry method is proposed to realize in situ deformation *** feature of the method is the combination of a high-speed camera and multiple laser Doppler vibrometers(LDVs)for synchronous *** high-speed camera is used to record and select effective interferograms,while the LDVs are used to measure the rigid body displacement caused by vibrations.A series of effective interferograms with known shifted phase values are obtained to calculate the deformation *** experimental results show that the method performs well in measuring static and dynamic deformations with high accuracy in vibrating environments.

关键词： speckle pattern interferometry laser Doppler vibrometers in situ deformation measurements

Small Cycles Property of Some Cremer Rational Maps and Polynomials

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 123-136页

作者： Rong fu Ji ZHOU Faculty of Science Yibin UniversityYibin 644000SichuanChina Department of Mathematical Sciences Sichuan Normal UniversityChengdu 610066China

This paper concerns the linearization problem on rational maps of degree d≥2 and polynomials of degree d>2 from the perspective of *** authors introduce a set l_(∞) of irrational numbers and show that if α∈l_(∞),then any rational map is not linearizable and has infinitely many cycles in every neighborhood of the fixed point with multiplier λ=e^(2πiα),Adding more constraints to cubic polynomials,they discuss the above problems by polynomial-like *** the family of polynomials,with the help of Yoccoz's method,they obtain its maximum dimension of the set in which the polynomials are non-linearizable.

关键词： Irrationally indifferent fixed point Linearization problem Small cycles property