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Recent Progress in Nanoscale Covalent Organic Frameworks for Cancer Diagnosis and Therapy

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Nano-Micro Letters 2021年第11期13卷 246-265页

作者： Shuncheng Yao Zhirong liu Linlin Li Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400People’s Republic of China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Covalent organic frameworks(COFs)as a type of porous and crystalline covalent organic polymer are built up from covalently linked and periodically arranged organic *** precise assembly,welldefined coordination network,and tunable porosity endow COFs with diverse characteristics such as low density,high crystallinity,porous structure,and large specific-surface area,as well as versatile functions and active sites that can be tuned at molecular and atomic *** unique properties make them excellent candidate materials for biomedical applications,such as drug delivery,diagnostic imaging,and disease *** realize these functions,the components,dimensions,and guest molecule loading into COFs have a great influence on their performance in various *** this review,we first introduce the influence of dimensions,building blocks,and synthetic conditions on the chemical stability,pore structure,and chemical interaction with guest molecules of ***,the applications of COFs in cancer diagnosis and therapy are ***,some challenges for COFs in cancer therapy are noted and the problems to be solved in the future are proposed.

关键词： Covalent organic frameworks Nanomedicine Drug delivery Cancer diagnosis and therapy

Asymptotic properties of distributed social sampling algorithm

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Science China(Information Sciences) 2020年第1期63卷 152-166页

作者： Qian liu Xingkang HE Haitao FANG The Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences ACCESS Linnaeus Centre School of Electrical Engineering and Computer ScienceKTH Royal Institute of Technology

Social sampling is a novel randomized message passing protocol inspired by social communication for opinion formation in social networks. In a typical social sampling algorithm, each agent holds a sample from the empirical distribution of social opinions at initial time, and it collaborates with other agents in a distributed manner to estimate the initial empirical distribution by randomly sampling a message from current distribution estimate. In this paper, we focus on analyzing the theoretical properties of the distributed social sampling algorithm over random networks. First, we provide a framework based on stochastic approximation to study the asymptotic properties of the algorithm. Then, under mild conditions, we prove that the estimates of all agents converge to a common random distribution, which is composed of the initial empirical distribution and the accumulation of quantized error. Besides, by tuning algorithm parameters, we prove the strong consistency, namely, the distribution estimates of agents almost surely converge to the initial empirical distribution. Furthermore, the asymptotic normality of estimation error generated by distributed social sample algorithm is addressed. Finally, we provide a numerical simulation to validate the theoretical results of this paper.

关键词： social networks opinion formation social sampling stochastic approximation random networks asymptotic normality

Effect of succinic acid on morphology transformation of the anhydrous magnesium carbonate particles prepared by magnesium chloride hexahydrate and urea

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Particuology 2024年第7期90卷 209-217页

作者： Song liu Guojun Cheng Zhongfeng Tang School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan232001China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Anhui Province Key Laboratory of Environment-friendly Polymer Materials Anhui UniversityHefei230601China

The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic *** effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal *** effect of the addition of succinic acid on the particles was similar to that of temperature *** morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μ*** MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time *** interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological *** pH,temperature,and time affected the molecular motion rate and crystal growth.

关键词： MgCO_(3) MgCl_(2)·6H_(2)O Urea Succinic acid Morphology

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中等缸径低速柴油机缸内燃烧与排放特性分析

船舶工程 2019年第S1期41卷 243-247,251页

作者：刘腾桂勇刘博刘辰朋中船动力研究院有限公司上海201206

针对某典型船用低速柴油机建立了流体仿真基本模型,并通过对标某一工况下的一维计算结果,确定了各项子模型及相关参数,基于此分析某特定喷油规律下缸内的燃烧与排放特性,并比较了不同燃油喷射时刻对各项特性造成的影响。结果表明,特定... 详细信息

针对某典型船用低速柴油机建立了流体仿真基本模型,并通过对标某一工况下的一维计算结果,确定了各项子模型及相关参数,基于此分析某特定喷油规律下缸内的燃烧与排放特性,并比较了不同燃油喷射时刻对各项特性造成的影响。结果表明,特定喷油规律可使柴油机单缸满足250bar(1 bar=0.1 MPa)设计爆压要求,且排气阀打开前NO主要集中在气缸中部,Soot集中在排气阀附近;有极少量油滴会被吹拂在气缸盖内壁,这部分油滴直接受高温气化后参与燃烧,可能会增加缸盖局部区域的热负荷,但是对缸内平均温度影响细微,故2个循环间隔中应尽量避免极少量的燃油进入缸内;推迟喷射可导致爆压、燃烧效率、NO排放单调递减,Soot排放单调递增,NO排放下降可达0.6~0.7倍,Soot排放上升可达56~114倍。

关键词：低速柴油机喷油规律燃烧特性排放特性

Empirical Likelihood Test for Regression Coefficients in High Dimensional Partially Linear Models

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Journal of Systems Science & Complexity 2021年第3期34卷 1135-1155页

作者： liu Yan REN Mingyang ZHANG Sanguo School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China

This paper considers tests for regression coefficients in high dimensional partially linear *** authors first use the B-spline method to estimate the unknown smooth function so that it could be linearly ***,the authors propose an empirical likelihood method to test regression *** authors derive the asymptotic chi-squared distribution with two degrees of freedom of the proposed test statistics under the null *** addition,the method is extended to test with nuisance *** show that the proposed method have a good performance in control of type-I error rate and *** proposed method is also employed to analyze a data of Skin Cutaneous Melanoma(SKCM).

关键词： Empirical likelihood test high dimensional analysis partially linear models regression coefficients

A review of the strengthening–toughening behavior and mechanisms of advanced structural materials by multifield coupling treatment

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 185-199页

作者： Xiu Song Lei Wang Yang liu The Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

The application of an external field is a promising method to control the microstructure of materials, leading to their improved performance. In the present paper, the strengthening and toughening behavior of some typical high-performance structural materials subjected to multifield coupling treatment, including electrostatic field, electro-pulse current, thermal field, and stress field, are reviewed in detail. In addition to the general observation that the plasticity of materials could be increased by multi-external fields, strength enhancement can be achieved by controlling atomic diffusion or phase transformations. The paper is not limited to the strengthening and toughening mechanisms of the multifield coupling effects on different types of structural materials but is intended to provide a generic method to improve both the strength and ductility of the materials. Finally, the prospects of the applications of multi-external fields have also been proposed based on current works.

关键词： multifield coupling structural materials strengthening toughening microstructure

3D hypothesis clustering for cross-view matching in multiperson motion capture

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Computational Visual Media 2020年第2期6卷 147-156页

作者： Miaopeng Li Zimeng Zhou Xinguo liu State Key Lab of CAD&CG Zhejiang UniversityHangzhou310058China

We present a multiview method for markerless motion capture of multiple people. The main challenge in this problem is to determine crossview correspondences for the 2 D joints in the presence of noise. We propose a 3 D hypothesis clustering technique to solve this problem. The core idea is to transform joint matching in 2 D space into a clustering problem in a 3 D hypothesis space. In this way, evidence from photometric appearance, multiview geometry, and bone length can be integrated to solve the clustering problem efficiently and robustly. Each cluster encodes a set of matched 2 D joints for the same person across different views, from which the 3 D joints can be effectively inferred. We then assemble the inferred 3 D joints to form full-body skeletons for all persons in a bottom–up way. Our experiments demonstrate the robustness of our approach even in challenging cases with heavy occlusion,closely interacting people, and few cameras. We have evaluated our method on many datasets, and our results show that it has significantly lower estimation errors than many state-of-the-art methods.

关键词： multi-person motion capture cross-view matching clustering human pose estimation

Dynamic analysis of wind turbine tower structures in complex ocean environment

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 999-1010页

作者： Guanzhong liu Xingming GUO Li ZHU Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mathematics and Computational Sciences Xiangtan UniversityXiangtan 411105Hunan ProvinceChina

Studying and analyzing the dynamic behavior of offshore wind turbines are of great importance to ensure the safety and improve the efficiency of such expensive *** this work,a tapered beam model is proposed to investigate the dynamic response of an offshore wind turbine tower on the monopile foundation assembled with rotating blades in the complex ocean *** environment factors like wind,wave,current,and soil resistance are taken into *** proposed model is ana-lytically solved with the Galerkin *** on the numerical results,the effects of various structure parameters including the taper angle,the height and thickness of the tower,the depth,and the diameter and the cement filler of the monopile on the funda-mental natural frequency of the wind turbine tower system are investigated in *** is found that the fundamental natural frequency decreases with the increase in the taper angle and the height and thickness of the tower,and increases with the increase in the diameter of the ***,filling cement into the monopile can effectively im-prove the fundamental natural frequency of the wind turbine tower system,but there is a critical value of the amount of cement maximizing the property of the *** research may be helpful in the design and safety evaluation of offshore wind turbines.

关键词： wind turbine tower structure dynamic analysis tapered beam fundamen-tal natural frequency complex ocean environment

Observer-based Iterative and Repetitive Learning Control for a Class of Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 990-998页

作者： Sheng Zhu Xuejie Wang Hong liu the department of information and electrical engineering zhejiang university city collegeHangzhou 310015China

In this paper, both output-feedback iterative learning control(ILC) and repetitive learning control(RLC) schemes are proposed for trajectory tracking of nonlinear systems with state-dependent time-varying uncertainties. An iterative learning controller, together with a state observer and a fully-saturated learning mechanism, through Lyapunov-like synthesis, is designed to deal with time-varying parametric uncertainties. The estimations for outputs, instead of system outputs themselves, are applied to form the error equation, which helps to establish convergence of the system outputs to the desired ones. This method is then extended to repetitive learning controller design. The boundedness of all the signals in the closed-loop is guaranteed and asymptotic convergence of both the state estimation error and the tracking error is established in both cases of ILC and RLC. Numerical results are presented to verify the effectiveness of the proposed methods.

关键词： Iterative learning control (ILC) observers repetitive learning control (RLC) time-varying parametrization.