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The First Five Years of a Phase Theory for Complex Systems and Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1728-1743页

作者： Dan Wang wei Chen Li qiu IEEE the Division of Decision and Control Systems KTH Royal Institute of Technology the Department of Mechanics and Engineering Science & the State Key Laboratory for Turbulence and Complex Systems Peking University the Hong Kong University of Science and Technology the Southern University of Science and Technology

In this paper, we review the development of a phase theory for systems and networks in its first five years, represented by a trilogy: Matrix phases and their properties; The MIMO LTI system phase response, its physical interpretations,the small phase theorem, and the sectored real lemma; The synchronization of a multi-agent network using phase *** the end, we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.

关键词： Linear systems Reviews Synchronization Complex systems

Microstructure and mechanical properties stability of pre-hardening treatment in Al-Cu alloys for pre-hardening forming process

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 539-551页

作者： Liping Tang Pengfei wei Zhili Hu qiu Pang Hubei Longzhong laboratory Xiangyang 441000China Hubei Key Laboratory of Advanced Technology for Automotive Components School of Automotive EngineeringWuhan University of TechnologyWuhan 430070China Hubei Engineering Research Center for Green&Precision Material Forming Wuhan University of TechnologyWuhan 430070China Key Laboratory of Metallurgical Equipment and Control Technology of Ministry of Education School of Machinery and AutomationWuhan University of Science and TechnologyWuhan 430081China

The stability of the microstructure and mechanical properties of the pre-hardened sheets during the pre-hardening forming(PHF)process directly determines the quality of the formed *** microstructure stability of the pre-hardened sheets was in-vestigated by differential scanning calorimetry(DSC),transmission electron microscopy(TEM),and small angle X-ray scattering(SAXS),while the mechanical properties and formability were analyzed through uniaxial tensile tests and formability *** results in-dicate that the mechanical properties of the pre-hardened alloys exhibited negligible changes after experiencing 1-month natural aging(NA).The deviations of ultimate tensile strength(UTS),yield strength(YS),and sheet formability(Erichsen value)are all less than 2%.Also,after different NA time(from 48 h to 1 month)is applied to alloys before pre-hardening treatment,the pre-hardened alloys possess stable microstructure and mechanical properties as ***,with the extension of NA time before pre-hardening treatment from 48 h to 1 month,the contribution of NA to the pre-hardening treatment is *** a yield strength increment of 20 MPa is achieved,with no loss in *** limited enhancement is mainly attributed to the fact that only a limited number of clusters are transformed into Guinier-Preston(GP)zones at the early stage of pre-hardening treatment,and the formation ofθ''phase inhibits the nucleation and growth of GP zones as the precipitated phase evolves.

关键词： Al-Cu alloy pre-hardened alloy natural aging mechanical properties microstructure

An Efficient Local Radial Basis Function Method for Image Segmentation Based on the Chan-Vese Model

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 1119-1134页

作者： Shupeng qiu Chujin Lin wei Zhao School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou510520China

In this paper,we consider the Chan–Vese(C-V)model for image segmentation and obtain its numerical solution accurately and *** this purpose,we present a local radial basis function method based on a Gaussian kernel(GA-LRBF)for spatial *** to the standard radial basis functionmethod,this approach consumes less CPU time and maintains good stability because it uses only a small subset of points in the whole computational ***,since the Gaussian function has the property of dimensional separation,the GA-LRBF method is suitable for dealing with isotropic ***,a numerical scheme that couples GA-LRBF with the fourth-order Runge–Kutta method is applied to the C-V model,and a comparison of some numerical results demonstrates that this scheme achieves much more reliable image segmentation.

关键词： Image segmentation Chan–Vese model local radial basis functionmethod Gaussian kernel Runge–Kuttamethod

Analysis of China's Electricity Price and Electricity Burden of Basic Industries under the Carbon Peak Target before 2030

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 481-491页

作者： Yue qiu Suyang Zhou wei Gu Xiao-Ping Zhang School of Electrical Engineering Southeast UniversityNanjingChina School of Electronic Electrical and System EngineeringUniversity of BirminghamU.K.

The Chinese government is deepening reformation of electricity prices during the 14th Five Year Plan period and has set a carbon emission reduction target of reaching carbon peak before *** this context,will the carbon emission target influence electricity pricing and will electricity price influence competitiveness of Chinese main industries are two questions needing to be *** paper compares China's electricity price level with the selected major countries in the world,and four typical industries are selected to evaluate their electricity burden ***,the correlation between residential electricity price and industrial electricity price and the influencing factors is analyzed,from the perspectives of scale,structure and *** to the model obtained by regression analysis,the electricity price level and corresponding residential and industrial electricity burden in 2025 and 2030 are *** Terms-Electricity burden,industrial electricity price,regression analysis,residential electricity price.

关键词： Electricity burden industrial electricity price regression analysis residential electricity price

The innovative safe herbicide dienediamine saves paraquat

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Molecular Plant 2024年第1期17卷 11-12页

作者： Jin-qiu Xia Ping Xu Cheng-bin Xiang Division of Life Sciences and Medicine Division of Molecular&Cell BiophysicsHefei National Science Center for Physical Sciences at the MicroscaleMOE Key Laboratory for Membraneless Organelles and Cellular DynamicsUniversity of Science and Technology of ChinaThe Innovation Academy of Seed DesignChinese Academy of SciencesHefeiAnhui Province 230027China Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterCAS Center for Excellence in Molecular Plant SciencesShanghai 201602China

Throughout the history of agriculture,the challenge of weed management has endured,necessitating significant investments to facilitate ideal crop growth and maximize *** for weed control mainly involve manual and chem... 详细信息

关键词： approach. manual chemical

Exact Box-Constrained Economic Operating Region for Power Grids Considering Renewable Energy Sources

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 514-523页

作者： Huating Xu bin Feng Chutong Wang Chuangxin Guo Jian qiu Mingyang Sun College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Department of Control Science and Engineering Zhejiang UniversityHangzhou 310027China

The growing integration of renewable energy sources manifests as an effective strategy for reducing carbon emissions. This paper strives to efficiently approximate the set of optimal scheduling plans(OSPs) to enhance the performance of the steady-state adaptive cruise method(SACM) of power grid, improving the ability of dealing with operational uncertainties. Initially, we provide a mathematical definition of the exact boxconstrained economic operating region(EBC-EOR) for the power grid and its dispatchable components. Following this, we introduce an EBC-EOR formulation algorithm and the corresponding bi-level optimization models designed to explore the economic operating boundaries. In addition, we propose an enhanced big-M method to expedite the computation of the EBCEOR. Finally, the effectiveness of the EBC-EOR formulation, its economic attributes, correlation with the scheduling plan underpinned by model predictive control, and the significant improvement in computational efficiency(over twelvefold) are verified through case studies conducted on two test systems..

关键词： Exact box-constrained economic operating region(EBC-EOR) big-M method intelligent scheduling steady-state adaptive cruise uncertainty renewable energy source

Prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae among healthy children under 5 years of age in Hainan Province, China

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Infectious Diseases of Poverty 2024年第1期13卷 42-52页

作者： Jian Wang Li qiu Shuang Bai wei Zhao Ao Zhang Jing Li Jun-Nan Zhang Shan-Shan Zhou Ren qiu Zhu Huang Jv-Xia Liu Ting-bin Wang Xue Sun Jiang Wu Qun Zheng bin He Min Lv Beijing Center for Disease Prevention and Control BeijingChina Beijing Research Center for Respiratory Infectious Diseases BeijingChina Hainan Provincial Center for Disease Control and Prevention HaikouChina Haikou Center for Disease Control and Prevention HaikouHainanChina Wanning Center for Disease Control and Prevention WanningHainanChina Baisha County Center for Disease Control and Prevention BaishaHainanChina Qiongzhong County Center for Disease Control and Prevention QiongzhongHainanChina

Background The thirteen-valent pneumococcal conjugate vaccine(PCV13)is not included in the national immu-nization program and is administered voluntarily with informed consent in *** preparation for assessing the impact of pilot introduction in Hainan Province,we conducted a carriage study among children under 5 years of age from four locations in Hainan Province,*** From March to June 2022,nasopharyngeal(NP)swabs,collected from healthy children aged younger than 59 months who lived in the 4 different locations(Haikou,Wanning,Baisha and Qiongzhong)in Hainan Province,were tested for pneumococcus using conventional *** isolates were serotyped using the Quel-lung *** factors associated with pneumococcal colonization were assessed using univariate analysis and multivariable logistic regression adjusting for age,daycare attendance and other *** Pneumococcus was isolated in 710(30.4%)of the 2333 children *** 737 pneumococci,29 serotypes were identifed;60.9%were PCV13 serotypes;the most common vaccine serotypes were 6B(20.4%),19F(13.0%),6A(11.9%)and 23F(6.1%);and the most common nonvaccine serotypes were 23A(12.9%),34(6.1%)and nontypeable(NT)pneumococci(5.6%).Children vaccinated with PCV13 had lower carriage(17.7%vs 32.5%;P=0.0001)and fewer PCV13 serotypes(41.9%vs 62.7%;P=0.0017)compared to unimmunized *** adjustment,NP carriage Was higher among children attending daycare(aOR=2.3,95%CI:1.7-3.2),living in rural areas(aOR=1.4,95%CI:1.1-1.8),living with siblings(aOR=1.3,95%CI:1.0-1.6)and whose mothers had completed senior high/technical sec-ondary school(aOR=1.5,95%CI:1.1-2.0).In contrast,completion of 3-4 doses of PCV13 were associated with a lower carriage rate(aOR=0.6,95%CI:0.4-0.9).Conclusions We established the baseline of pneumococcal carriage,serotype distribution and PCV13 immuni-zation rates among healthy children under 5 years of age in Hainan Province,prior to the introduction of PCV13 into th

关键词： Pneumococcus Nasopharyngeal carriage Serotypes distribution Children Hainan Province China

Research on the Stability Analysis Method of DC Microgrid Based on Bifurcation and Strobe Theory

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Energy Engineering 2024年第4期121卷 987-1005页

作者： wei Chen Nan qiu Xusheng Yang School of Electrical Engineering and Information Engineering Lanzhou University of TechnologyLanzhou730050China

During the operation of a DC microgrid,the nonlinearity and low damping characteristics of the DC bus make it prone to oscillatory *** this paper,we first establish a discrete nonlinear system dynamic model of a DC microgrid,study the effects of the converter sag coefficient,input voltage,and load resistance on the microgrid stability,and reveal the oscillation mechanism of a DC microgrid caused by a single ***,a DC microgrid stability analysis method based on the combination of bifurcation and strobe is used to analyze how the aforementioned parameters influence the oscillation characteristics of the ***,the stability region of the system is obtained by the Jacobi matrix eigenvalue *** simulation verifies the feasibility and effectiveness of the proposed method.

关键词： DC microgrid bifurcation nonlinear dynamics stability analysis oscillation characteristics

Relationship between preoperative psychological stress and shortterm prognosis in elderly patients with femoral neck fracture

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World Journal of Psychiatry 2024年第6期14卷 838-847页

作者： Wen-Hui Fu Zhi-Long Hu Yuan-Jun Liao Ri-Jiang Chen Jian-bin qiu Wu-Tang Que Wan-Tao Wang wei-Hua Li wei-bin Lan Department of Orthopedics Longyan First Affiliated Hospital of Fujian Medical UniversityLongyan 361000Fujian ProvinceChina

BACKGROUND Older adults are at high risk of femoral neck fractures(FNFs).Elderly patients face and adapt to significant psychological burdens,resulting in different degrees of psychological stress *** hip replacement is the preferred treatment for FNF in elderly patients;however,some patients have poor postoperative prognoses,and the underlying mechanism is *** speculated that the postoperative prognosis of elderly patients with FNF may be related to preoperative psychological *** To explore the relationship between preoperative psychological stress and the short-term prognosis of elderly patients with *** In this retrospective analysis,the baseline data,preoperative 90-item Symptom Checklist score,and Harris score within 6 months of surgery of 120 elderly patients with FNF who underwent total hip arthroplasty were *** analyzed the indicators of poor short-term postoperative prognosis and the ability of the indicators to predict poor prognosis and compared the correlation between the indicators and the Harris *** Anxiety,depression,garden classification of FNF,cause of fracture,FNF reduction quality,and length of hospital stay were independent influencing factors for poor short-term postoperative prognoses in elderly patients with FNF(P<0.05).The areas under the curve for anxiety,depression,and length of hospital stay were 0.742,0.854,and 0.749,*** sensitivities of anxiety,depression,garden classification of FNF,and prediction of the cause of fracture were 0.857,0.786,0.821,and 0.821,*** specificities of depression,FNF quality reduction,and length of hospital stay were the highest at 0.880,0.783,and 0.761,***,depression,and somatization scores correlated moderately with Harris scores(r=-0.523,-0.625,and-0.554;all P<0.001).CONCLUSION Preoperative anxiety,depression,and somatization are correlated with poor short-term prognosis in elderly patients with FNF and warrant consid

关键词： Psychological stress Old age Femoral neck fracture Hip replacement Short-term prognosis Correlation