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SOLVING SYSTEMS OF PHASELESS EQUATIONS VIA RIEMANNIAN OPTIMIZATION WITH OPTIMAL SAMPLING COMPLEXITY

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Journal of Computational Mathematics 2024年第3期42卷 755-783页

作者： Jianfeng cai Ke Wei Department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina School of Data Science Fudan UniversityShanghaiChina

A Riemannian gradient descent algorithm and a truncated variant are presented to solve systems of phaseless equations|Ax|^(2)=*** algorithms are developed by exploiting the inherent low rank structure of the problem based on the embedded manifold of rank-1 positive semidefinite *** recovery guarantee has been established for the truncated variant,showing that the algorithm is able to achieve successful recovery when the number of equations is proportional to the number of *** key ingredients in the analysis are the restricted well conditioned property and the restricted weak correlation property of the associated truncated linear *** evaluations show that our algorithms are competitive with other state-of-the-art first order nonconvex approaches with provable guarantees.

关键词： Phaseless equations Riemannian gradient descent Manifold of rank-1 and positive semidefinite matrices Optimal sampling complexity

Platelet-based bioactive systems guided precision targeting and immune regulation for cancer therapy

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Nano Research 2024年第9期17卷 8269-8284页

作者： Xinyi cai Long Qiu Zhenying Diao Lintao cai Ting Yin Hong Pan Guangdong Key Laboratory of Nanomedicine CAS-HK Joint Lab of BiomaterialsCAS Key Laboratory of Biomedical Imaging Science and SystemInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced Technology(SIAT)Chinese Academy of SciencesShenzhen 518055China School of pharmacy Guangdong Medical UniversityDongguan 523808China Sino-Euro Center of Biomedicine and Health Shenzhen 518024China

The antitumor effects of conventional drug carriers are often attenuated and limited in application by biological barriers associated with tumor heterogeneity and resistance brought about by low tumor *** the rapid development of nanotechnology,naturally derived bioactive materials,and live cell carriers,a promising strategy emerges for targeting the tumor microenvironment(TME)for precision cancer *** unique injury-targeting properties of platelets can significantly extend functional activity,which cannot be achieved with conventional *** this review,three strategies based on platelet-engineered materials are systematically described,namely nanoparticles for platelet membrane camouflage,engineered activated platelets,and targeted-platelets ***-based nanomaterials can effectively coordinate local and distant tumor-host crosstalk with controlled active tumor site recognition and killing effects due to the presence of specific membrane proteins on the surface and the self-secretion of a large number of *** advances in platelets for effectively overcoming biological barriers and reducing immune resistance in cancer immunotherapy applications will be discussed in future clinical *** review provides an overview of recent research advances in platelet-based bioactive material-directed immunotherapy and chemotherapy to inform future antitumor combination therapies.

关键词： platelets bionic targeting immune modulation precision therapy deep penetration

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产业集聚技术溢出与创新效应的经济学分析

现代财经（天津财经大学学报） 2008年第8期28卷 65-69,82页

作者：刘禹宏蔡志强天津商业大学经济学院天津300134

溢出效应表现为从外部对经济主体带来利益或损失。本文讨论了产业集聚企业间技术创新相对溢出的问题,分析了产业集聚企业技术创新溢出效应,技术溢出与企业技术创新等问题,从而探求技术溢出与保护的博弈均衡途径。

关键词：产业集聚技术创新溢出经济博弈

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PP-g-AM的制备及其应用

塑料工业 2000年第1期28卷 1-2,15页

作者：韦春蔡志强吕建桂林工学院材料工程系 541004 桂林电器科学研究所 541004

用熔融接枝方法制备了聚丙烯接枝丙烯酰胺（ＰＰｇＡＭ），用红外光谱、化学滴定方法对接枝物进行了定性和定量的表征，讨论了单体、引发剂用量、接枝温度、反应时间对接枝率的影响，并将接枝物应用于与ＰＡ６共混。结果表明：当... 详细信息

用熔融接枝方法制备了聚丙烯接枝丙烯酰胺（ＰＰｇＡＭ），用红外光谱、化学滴定方法对接枝物进行了定性和定量的表征，讨论了单体、引发剂用量、接枝温度、反应时间对接枝率的影响，并将接枝物应用于与ＰＡ６共混。结果表明：当ＤＣＰ用量为０．１５％、ＡＭ为６％、挤出机转速为４０ｒ／ｍｉｎ，可获得最佳的接枝率，经接枝改性的ＰＰ与ＰＡ６共混，其冲击强度明显提高。

关键词：熔融接枝接枝率聚丙烯丙烯酰胺

Optimized silicon fertilization regime weakens cadmium translocation and increases its biotransformation in rice tissues

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The Crop Journal 2024年第4期12卷 1041-1053页

作者： Bogui Pan Yixia cai Kunzheng cai Jihui Tian Wei Wang College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Provincial Key Laboratory of Eco-Circular Agriculture Guangzhou 510642GuangdongChina Key Laboratory of Tropical Agricultural Environment in South China Ministry of Agriculture and Rural AffairsGuangzhou 510642GuangdongChina College of Agriculture South China Agricultural UniversityGuangzhou 510642GuangdongChina

In acidic paddy fields of South China,rice(Oryza sativa L.)faces the dual challenges of cadmium(Cd)toxicity and silicon(Si)*** previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice,the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain *** study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes:Si(T)(all Si added before transplanting),Si(J)(all Si added at jointing),and Si(TJ)(half Si added both before transplanting and at jointing).The findings revealed that the regime of Si(TJ)was more beneficial to rice health and grain safety than Si(T)and Si(J).The osmotic regulators such as proline,soluble sugars,and soluble proteins were significantly boosted by Si(TJ)compared to other Si treatments,and which enhanced membrane integrity,balanced intracellular pH,and increased Cd tolerance of ***,Si(TJ)was more effective than Si(T)and Si(J)on the Cd sequestration in the cell wall,Cd bio-passivation,and the down-regulated expression of the Cd transport *** concentrations of Cd in the xylem and phloem treated with Si(TJ)were reduced ***,Si(TJ)facilitated much more Cd bound with the outer layer proteins of grains,and promoted Cd chelation and complexation by phytic acid,phenolics,and ***,Si(TJ)outperformed Si(T)and Si(J)in harmonizing the phycological processes,inhibiting Cd translocation,and enhancing Cd detoxification in rice *** the split Si application strategy offers potential for reducing Cd toxicity in rice grain.

关键词： Cadmium Silicon Growth stages Translocation and accumulation Rice Safe production

基于混合C-谱的K-终端网络置换重要度计算方法

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西北工业大学学报 2019年第5期37卷 897-902页

作者：杜永军郭雅琪蔡志强张攀兰州理工大学理学院甘肃兰州730050 西北工业大学机电学院陕西西安710072

重要度可以量化网络边对整个网络可靠性(故障)的影响程度,而C-谱是研究网络可靠性及重要度的一个有力工具。假设网络中每条边具有相同的可靠性,将二态关联系统中的传统置换重要度推广到K-终端网络,设计了基于混合C-谱的蒙特卡罗算法来... 详细信息

重要度可以量化网络边对整个网络可靠性(故障)的影响程度,而C-谱是研究网络可靠性及重要度的一个有力工具。假设网络中每条边具有相同的可靠性,将二态关联系统中的传统置换重要度推广到K-终端网络,设计了基于混合C-谱的蒙特卡罗算法来评估该重要度。理论分析表明:当网络具有某种特殊结构或者边的可靠性足够大时,网络边的置换重要度排序仅依赖于网络结构,而与边的可靠性无关。最后,结合算例演示了如何利用传统置换重要度评估K-终端网络中网络边的重要程度。

关键词： K-终端网络置换重要度混合C-谱蒙特卡罗

Novel method for measuring surface residual stress using flat-ended cylindrical indentation

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Chinese Journal of Aeronautics 2024年第8期37卷 486-495页

作者： Guangzhao HAN Lixun cai Xiaokun LIU Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China Zhengzhou Machinery Research Institute Transmission Technology Co. LtdZhengzhou 518115China

Instrumented indentation is a promising technique for estimating surface residual stresses and mechanical properties in engineering *** relative difference between the indentation loads for unstressed and stressed specimens was selected as the key parameter for measuring surface residual stresses in flat-ended cylindrical *** on the equivalent material method and finite element simulations,a dimensionless mapping model with six constants was established between the relative load difference,constitutive model parameters,and normalized residual stress.A novel method for measuring the surface residual stress and constitutive model parameters of metallic material through flat-ended cylindrical indentations was proposed using this model and a mechanical properties determination *** simulations were conducted using numerous elastoplastic materials with different residual stresses to verify the proposed model;good agreements were observed between the predicted residual stresses and those previously applied in finite element ***-ended cylindrical indentation tests were performed on four metallic materials using cruciform specimens subjected to various equibiaxial *** results exhibited good conformance between the stress–strain curves obtained using the proposed method and those from traditional tensile tests,and the absolute differences between the predicted residual stresses and applied stresses were within 40 MPa in most cases.

关键词： Instrumented indentation Residual stress Finite element simulation Equivalent material method Mechanical property

Pathway Planning of Nuclear Power Development Incorporating Assessment of Nuclear Event Risk

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 500-513页

作者： Xinxin Yang Yusheng Xue Bin cai School of Electrical Engineering Southeast UniversityNanjingChinaand they are also with State Grid Electric Power Research Institute(NARI Group Corporation)NanjingChina State Key Laboratory of Smart Grid Protection and Operation Control NanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChina

The nuclear event risk(NER)is an important and disputed factor that should be reasonably considered when planning the pathway of nuclear power development(NPD)to assess the benefits and risks of developing nuclear power more *** paper aims to explore the impact of nuclear events on NPD pathway *** influence of nuclear events is quantified as a monetary risk component,and an optimization model that incorporates the NER in the objective function is *** optimize the pathway of NPD in the lowcarbon transition course of power supply structure evolution,a simulation model is built to deduce alternative NPD pathways and corresponding power supply evolution scenarios under the constraint of an exogenously assigned carbon emission pathway(CEP);moreover,a method is proposed to describe the CEP by superimposing the maximum carbon emission space and each carbon emission reduction(CER)component,and various CER components are clustered considering the emission reduction characteristics and resource endowments of different power generation technologies.A case study is conducted to explore the impact of NER and its risk valuation uncertainty on NPD pathway *** method presented in this paper allows the impact of nuclear events on NPD pathway planning to be quantified and improves the level of coordinated optimization of benefits and risks.

关键词： Low-carbon transition power supply structure evolution nuclear power development(NPD) quantitative analysis nuclear event risk evaluation

Optimization of resource allocation in FDD massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 117-125页

作者： Jun cai Chuan Yin Youwei Ding School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing 210046China School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The performance of massive MIMO systems relies heavily on the availability of Channel State Information at the Transmitter(CSIT).A large amount of work has been devoted to reducing the CSIT acquisition overhead at the pilot training and/or CsI feedback *** fact,the downlink communication generally includes three stages,i.e.,pilot training,CsI feedback,and data *** three stages are mutually related and jointly determine the overall system ***,there exist few studies on the reduction of csIT acquisition overhead from the global point of *** this paper,we integrate the Minimum Mean Square Error(MMSE)channel estimation,Random Vector Quantization(RVQ)based limited feedback and Maximal Ratio Combining(MRC)precoding into a unified framework for investigating the resource allocation *** particular,we first approximate the covariance matrix of the quantization error with a simple expression and derive an analytical expression of the received Signal-to-Noise Ratio(SNR)based on the deterministic equivalence *** the three performance metrics(the spectral efficiency,energy efficiency,and total energy consumption)oriented problems are formulated *** practical system requirements,these three metrics can be collaboratively ***,we propose an optimization solver to derive the optimal partition of channel coherence *** results verify the benefits of the proposed resource allocation schemes under three different scenarios and illustrate the tradeoff of resource allocation between three stages.

关键词： Massive MIMO FDD CSIT Resource allocation