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Cubic Regularization Methods with Second-Order Complexity Guarantee Based on a New Subproblem Reformulation

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Journal of the Operations Research Society of China 2022年第3期10卷 471-506页

作者： Ru-Jun Jiang Zhi-shuo zhou Zi-Rui zhou School of Data Science Fudan UniversityShanghai 200433China Huawei Technologies Canada BurnabyBCCanada

The cubic regularization(CR)algorithm has attracted a lot of attentions in the literature in recent *** propose a new reformulation of the cubic regularization *** reformulation is an unconstrained convex problem that requires computing the minimum eigenvalue of the ***,based on this reformulation,we derive a variant of the(non-adaptive)CR provided a known Lipschitz constant for the Hessian and a variant of adaptive regularization with cubics(ARC).We show that the iteration complexity of our variants matches the best-known bounds for unconstrained minimization algorithms using first-and second-order ***,we show that the operation complexity of both of our variants also matches the state-of-the-art bounds in the *** experiments on test problems from CUTEst collection show that the ARC based on our new subproblem reformulation is comparable to the existing algorithms.

关键词： Cubic regularization subproblem First-order methods Constrained convex optimization Complexity analysis

Seasonal variation of atmospheric coupling with oceanic mesoscale eddies in the North Pacific Subtropical Countercurrent

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Acta Oceanologica Sinica 2022年第10期41卷 109-118页

作者： Bowen Sun Baofu Li Jingyu Yan Yuqi zhou shuo zhou School of Geography and Tourism Qufu Normal UniversityRizhao276800China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao266071China

This study investigated the seasonal variation in the atmospheric response to oceanic mesoscale eddies in the North Pacific Subtropical Countercurrent(STCC)and its mechanism,based on satellite altimetric and reanalysis *** mesoscale eddy in the study area is more active in summer,the sea surface temperature(SST)anomaly associated with mesoscale eddies is more intense and dipolar in winter,which is largely due to the larger background SST ***,the impact of the oceanic eddy on sea surface wind speed and heat flux is strongest in winter,whereas its effect on precipitation rate is more significant in *** study revealed that the SST gradient in STCC could impact the atmosphere layer by up to 800 h Pa(900 h Pa)in boreal winter(summer)through the dominant vertical mixing ***,the intensity of the SST gradient causes such seasonal variation in mesoscale air-sea coupling in the study *** brief,a stronger(weaker)background SST gradient field in wintertime(summertime)leads to a larger(smaller)eddy-induced SST anomaly,thus differently impacting atmosphere instability and transitional kinetic energy flux over oceanic eddies,leading to seasonal variation in mesoscale air-sea coupling intensity.

关键词： atmospheric response on mesoscale eddy seasonal variation subtropical countercurrent sea surface temperature-wind coupling

Effect of Solvophilic Chain Length in PISA Particles on Pickering Emulsion

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Chinese Journal of Chemistry 2021年第12期39卷 3448-3454页

作者： Min Zeng shuo zhou Xiaofeng Sui Jinying Yuan Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Key Lab of Science and Technology of Eco-textile Ministry of EducationCollege of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The morphology of polymeric nanoparticles prepared by polymerization-induced self-assembly(PISA)is depended on the degree of polymerization of the solvophilic and solvophobic ***,a series of poly(N,N-dimethylaminoethyl methacrylate)-b-poly(benzyl methacrylate)(PDMA-b-PBzMA)diblock copolymer spherical nanoparticles were synthesized via reversible addition-frag-mentation chain transfer(RAFT)mediated *** diblock copolymer nanoparticles are with nearly the same hydrodynamic size and solvophobic chain length,but with different solvophilic chain *** used these nanoparticles to stabilize the oil-in-water Pickering *** find that the stability of Pickering emulsion increases with the length of solvophilic chain of the ***,the droplet size of the Pickering emulsion can be tailored by varying the oil/water ratio and concentration of nanoparticles.

关键词： Pickering emulsion Polymerization-induced self-assembly Polymerization Block copolymer Nanoparticles

The influence of compact and ordered carbon coating on solid-state behaviors of silicon during electrochemical processes

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Carbon Energy 2020年第1期2卷 143-150页

作者： shuo zhou Chen Fang Xiangyun Song Gao Liu Energy Storage and Distributed Resources Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia

To address the issues of large volume change and low conductivity of silicon(Si)materials,carbon coatings have been widely employed as surface protection agent and conductive medium to encapsulate the Si materials,which can improve the electrochemical performance of Si-based *** has been a strong demand to gain a deeper understanding of the impact of efficient carbon coating over the lithiation and delithiation process of Si ***,we report the first observation of the extended two-phase transformation of carbon-coated Si nanoparticles(Si/C)during electrochemical *** Si/C nanoparticles were prepared by sintering Si nanoparticles with polyvinylidene chloride *** Si/C electrode underwent a two-phase transition during the first 20 cycles at 0.2 C,but started to engage in solid solution reaction when the ordered compact carbon coating began to *** higher current density conditions,the electrode was also found to be involved in solid solution reaction,which,however,was due to the overwhelming demand of kinetic property rather than the breaking of the carbon *** comparison,the Si/C composites prepared with sucrose possessed more disordered and porous carbon structures,and presented solid solution reaction throughout the entire cycling process.

关键词： anode carbon coating electrochemical behavior lithium-ion batteries silicon

Using Virtual Reality to Promote Physical Activity

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Journal of Software Engineering and Applications 2020年第11期13卷 312-326页

作者： shuo zhou Department of Community and Behavioral Health Colorado School of Public Health Aurora CO USA Division of Cancer Prevention and Control University of Colorado Cancer Center Aurora CO USA

The purpose of this research is to develop an immersive virtual fitness center as an intervention to promote physical activity and examine its impacts on users’ exercise plans and exercise behaviors. The virtual reality (VR)-based intervention includes three main features: enabling the users to control their avatar, personalizing the avatar to look the same as the user, and visualizing the positive consequences of exercising. We conducted an experiment to randomly assign participants to two treatment groups: experiencing either the self or another person losing weight because of exercising in the virtual environment. The findings demonstrated that the self-avatar group exercised more in the voluntary section than the other-avatar group. However, participants in the self-avatar condition perceived a lower level of sense of presence compared to participants in the other-avatar condition. Compared to people in the control condition who watched and followed the exercise from a workout video, those who exercised in the virtual fitness center, regardless of whether the avatar was based on the self’s image or another person’s image, planned to spend more time on exercising in the following week. Theoretical and practical implications for using VR technology to promote health-related behavioral change, and why personalization decreases perceived sense of presence in the virtual environment are discussed.

关键词： Virtual Reality Personalization Visualization Presence Physical Activity/Exercise

Least-Squares Solutions of Matrix Equations(AX = B,XC = D) for Hermitian Reflexive (Anti-Hermitian Reflexive) Matrices and Its Approximation

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Journal of Mathematical Research and Exposition 2011年第6期31卷 1108-1116页

作者： shuo zhou Shi Tong YANG Wen WANG School of Mathematical Sciences Northeast Dianli University Jilin 132012 P. R. China

In this paper,the Hermitian reflexive（Anti-Hermitian reflexive）least-squares so-lutions of matrix equations（AX = B,XC = D）are *** special properties of partitioned matrices and Hermitian reflexive（Anti-Hermitian reflexive）matrices,the general expression of the solution is ***,the related optimal approximation problem to a given matrix over the solution set is considered.

关键词： matrix equations Hermitian reflexive matrix Anti-Hermitian reflexive matrix least-squares solution optimal approximation.

RNA interference targeting ω-secalin genes differentially affects the processing quality in a wheat T1BL·1RS translocation line

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The Crop Journal 2021年第2期9卷 456-464页

作者： shuo zhou Cuimian Zhang He Zhao Mengyu Lyu Fushuang Dong Yongwei Liu Fan Yang Haibo Wang Jianfang Chai Hebei Province Plant Genetic Engineering Center Institute of Genetics and PhysiologyHebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051HebeiChina

Wheat-rye T1BL·1RS translocation lines are widely used,especially in China,but their processing quality is generally *** interfering expression vector targeting theω-secalin genes was constructed with the 1Bx7 seed-specific ***-mediated genetic transformation of the wheat cultivar KN199 carrying the T1BL·1RS translocation generated 10 transgenic *** representative transgenic lines,8-2 and 13-7,were selected for *** with the control,the two transformants showed an up to 4.5-fold decrease in totalω-secalins and various levels of decrease inω-gliadins,γ-gliadins,and low-molecular-weight glutenins.A decrease in high molecular weight(HMW)glutenin 1Bx7 was detected only in 8-2,owing possibly to promoter *** levels ofα-gliadins were observed in both transformants,but increased levels of HMW glutenins were observed only in *** 13-7 showed increases in gluten index,Zeleny sedimentation value,stabilization time,and maximum *** bread volume was 849.6 mL,an 11.9%increase over that of the *** 8-2 showed decreases in these parameters,but its total cake-making quality score was 88,an 17.3%increase over that of the *** study demonstrates that the same RNAi construct may produce different effects on wheat processing quality and highlights the influence of the vector promoter in RNA interference.

关键词： T1BL·1RS Quality improvement RNA interference Secalin Triticum aestivum

NiZr,AlZr和BCr相局域原子短程序特征

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物理学报 2014年第6期63卷 176-181页

作者：陈季香周朔瑶大连海事大学物理系大连116026

晶体和非晶合金具有以近邻多面体团簇为特征的微结构,这些团簇包含有形成其母相的空间局域原子短程序结构信息.本文正是从局域原子团簇特征出发,详细分析了传统晶体相描述中具有相同结构的NiZr,AlZr和BCr相,结果表明它们却具有不同的局... 详细信息

晶体和非晶合金具有以近邻多面体团簇为特征的微结构,这些团簇包含有形成其母相的空间局域原子短程序结构信息.本文正是从局域原子团簇特征出发,详细分析了传统晶体相描述中具有相同结构的NiZr,AlZr和BCr相,结果表明它们却具有不同的局域原子特征.这种不同可能是由单胞大小及原子占位略有不同造成的.由于这种不同于传统的晶体学描述方法给出了微观结构特点,对晶体相的重新认知及材料设计会大有帮助.

关键词：晶体相局域原子特征团簇

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战术通信波形参数对射频低截获性能影响分析

兵器装备工程学报 2021年第S1期42卷 271-274页

作者：周硕南昌大学信息工程学院南昌330000

数据链的载波频率、带宽和调制方式是无源探测系统分选识别所需的重要目标特征参数,本文综合仿真了上述通信波形特征参数对循环特征检测器接收机工作特性的影响,将显示循环特征检测器的接收机工作特性对跳频、调制和符号速率的复杂度的... 详细信息

数据链的载波频率、带宽和调制方式是无源探测系统分选识别所需的重要目标特征参数,本文综合仿真了上述通信波形特征参数对循环特征检测器接收机工作特性的影响,将显示循环特征检测器的接收机工作特性对跳频、调制和符号速率的复杂度的结果分成非常敏感、敏感和比较敏感三类,设计复杂的跳频、调制和符号速率等通信波形特征参数以显著降低循环特征检测器的检测概率。

关键词：战术数据链低截获概率波形参数循环特征检测器调制