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Research on Development Strategies for“Double First-Class”Construction of Subject Service in University Libraries
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作者 Haixin Liu Liping Liu Yanan Zhang 《Journal of Contemporary Educational Research》 2025年第1期25-31,共7页
This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”c... This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”construction and university library subject services,the study analyzes the current state of subject services,including resource development,service models,and team building.Drawing on domestic and international case studies,the paper proposes a series of targeted and practical strategies to enhance the quality of subject services in university libraries,thereby providing robust support for the advancement of the“double first-class”initiative. 展开更多
关键词 double first-class”construction University library Subject service Development strategy
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基于Double-Double理论的机身结构优化设计
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作者 郑传祥 宋兆波 +5 位作者 俞轶宸 卢锦杰 荆磊 陈思燃 苏璐 Stephen Tsai 《高科技纤维与应用》 2025年第2期43-50,共8页
Double-Double(下称DD)理论是由斯坦福大学Stephen Tsai教授首先提出,其理论依据是给定材料的复合材料层合板的蔡氏模量为常量,与纤维的敷设角度和铺设顺序无关。利用层合板的这个特点,常用传统的层合板可以用二个角度±φ、±... Double-Double(下称DD)理论是由斯坦福大学Stephen Tsai教授首先提出,其理论依据是给定材料的复合材料层合板的蔡氏模量为常量,与纤维的敷设角度和铺设顺序无关。利用层合板的这个特点,常用传统的层合板可以用二个角度±φ、±ψ的四种组合来替代。如果根据载荷情况对φ、ψ的数值进行优化,则层合板的承载性能可以得到提高;如果采用相同的安全系数,则层数可以减少达到减重的目的。本文以机身研究对象,基于DD理论对机身进行优化设计,通过计算可以发现,相同载荷下,机身重量可以得到较大的减轻。 展开更多
关键词 double-double理论 机身 优化 设计
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基于Double Q-Learning的改进蝗虫算法求解分布式柔性作业车间逆调度问题
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作者 胡旭伦 唐红涛 《机床与液压》 北大核心 2025年第20期52-63,共12页
针对分布式柔性作业车间中存在的资源分配不均和调度稳定性不足问题,构建以最小化最大完工时间、机器总能耗和偏离度为目标的逆调度数学模型,提出一种基于Double Q-Learning的改进多目标蝗虫优化算法(DQIGOA)。针对该问题设计一种混合... 针对分布式柔性作业车间中存在的资源分配不均和调度稳定性不足问题,构建以最小化最大完工时间、机器总能耗和偏离度为目标的逆调度数学模型,提出一种基于Double Q-Learning的改进多目标蝗虫优化算法(DQIGOA)。针对该问题设计一种混合三层编码方式;提出一种基于逆调度特点的种群初始化方式以提高种群质量;引入权重平衡因子来提高非支配解存档中解集的多样性;将强化学习中的Double Q-Learning机制融入非支配解的选择过程,通过动态动作策略优化目标解的选取,提升调度方案的全局搜索能力与局部优化效率。最后构建26组算例,通过策略有效性分析证明了所提策略可显著提升DQIGOA算法的性能,并通过与NSGA-II、DE和SPEA-II算法进行对比证明DQIGOA算法的有效性。结果表明:相比NSGA-II、DE和SPEA-II算法,DQIGOA算法在HV、IGD、SP指标上均有优势,证明了DQIGOA能够有效提升解的收敛速度和多样性分布,在动态扰动条件下表现出更强的鲁棒性。 展开更多
关键词 分布式柔性作业车间 逆调度 蝗虫算法 double Q-Learning机制
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基于CLASS的师幼互动质量评估研究 被引量:2
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作者 金芳 富建业 《贵州师范学院学报》 2025年第5期39-48,共10页
通过元分析对中国2017年1月至2024年4月期间的师幼互动质量进行了深入探讨,并基于CLASS工具对1389份样本数据进行了综合评估。研究发现,中国师幼互动在情感支持领域表现良好,尤其在积极氛围维度上得分较高,但在教育支持领域,尤其是认知... 通过元分析对中国2017年1月至2024年4月期间的师幼互动质量进行了深入探讨,并基于CLASS工具对1389份样本数据进行了综合评估。研究发现,中国师幼互动在情感支持领域表现良好,尤其在积极氛围维度上得分较高,但在教育支持领域,尤其是认知发展方面存在不足。研究还揭示了师幼互动质量在地区、年龄班及活动领域的显著差异:北部地区、大班及社会领域的师幼互动质量较高;而西部和南部地区、中班及艺术与语言领域的互动质量则相对较低。最后,提出了加强幼儿认知与创造性思维培养、优化教育氛围、强化幼儿主体性以及差异化优化师幼互动的策略。研究结果为改善幼儿园教育实践和政策制定提供了数据支持和方向指导。 展开更多
关键词 师幼互动质量 元分析 class评估
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Boosting characteristic emissions of lanthanide in Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) double perovskites via mixing halide 被引量:2
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作者 Shujian Wang Dejian Chen +4 位作者 Jie Hu Sisi Liang Kunyuan Xu Maochun Hong Haomiao Zhu 《Journal of Rare Earths》 2025年第1期39-46,I0002,共9页
Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency betw... Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency between self-trapped exciton(STE)and Ln^(3+)ions,the characteristic emissions of Ln^(3+)ions are not prominent.Furthermore,the energy transfer mechanism between STE and Ln^(3+)ions is also elusive and requires in-depth study.We chose trace Bi^(3+)-doped Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) as a representative DP matrix to demonstrate that by tuning the bromide concentration,the Ln^(3+)emission can be greatly enhanced.Such enhanced STE and Ln^(3+)ions energy transfer originates from the high covalency of Ln-Br bond,which contributes to improve ment of the characteristic emission of Ln^(3+)ions.Furthermo re,optical spectroscopy reveals that the energy transfer mechanism from DP to Eu^(3+)ions is different from all the other doped Ln^(3+)ions.The energy transfer from DP to Eu^(3+)ions is mostly through Eu-Br charge transfer while the other Ln^(3+)ions are excited by energy transfer from STE.The distinct energy transfer mechanism has resulted from the energy separation between the excited energy level of Ln^(3+)ions and the bottom of conduction band of DP.With increasing the energy separation,the energy transfer from STE to Ln^(3+)ions is less efficient because of the generation of a larger number of phonons and finally becomes impossible for Eu^(3+)ions.Our results provide new insight into tuning the energy transfer of Ln^(3+)-doped DP NCs. 展开更多
关键词 double perovskitenanocrystal Lead free Lanthanideions Energytransfer Rare earths
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Optimal Production Capacity Matching for Blockchain-Enabled Manufacturing Collaboration With the Iterative Double Auction Method 被引量:1
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作者 Ying Chen Feilong Lin +2 位作者 Zhongyu Chen Changbing Tang Cailian Chen 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期550-562,共13页
The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a block... The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a blockchain-enabled manufacturing collaboration framework is proposed,with a focus on the production capacity matching problem for blockchainbased peer-to-peer(P2P)collaboration.First,a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain.Second,an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants.Third,a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information.It facilitates automation of the matching process while protecting users'privacy via blockchainbased smart contracts.Finally,simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4%compared to the Bayesian game-based approach,makes all participants profitable,and achieves 90%fairness of enterprises. 展开更多
关键词 Blockchain iterative double auction manufacturing collaboration production capacity matching
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Hemoglobin glycation index among adults with type 1 diabetes:Association with double diabetes features 被引量:1
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作者 Xiao-Lin Ji Min Yin +5 位作者 Chao Deng Li Fan Yu-Ting Xie Fan-Su Huang Yan Chen Xia Li 《World Journal of Diabetes》 2025年第4期153-165,共13页
ACKGROUND The hemoglobin glycation index(HGI)represents the discrepancy between the glucose management indicator(GMI)based on mean blood glucose levels and laboratory values of glycated hemoglobin(HbA1c).The HGI is a ... ACKGROUND The hemoglobin glycation index(HGI)represents the discrepancy between the glucose management indicator(GMI)based on mean blood glucose levels and laboratory values of glycated hemoglobin(HbA1c).The HGI is a promising indicator for identifying individuals with excessive glycosylation,facilitating personalized evaluation and prediction of diabetic complications.However,the factors influencing the HGI in patients with type 1 diabetes(T1D)remain unclear.Autoimmune destruction of pancreaticβcells is central in T1D pathogenesis,yet insulin resistance can also be a feature of patients with T1D and their coexistence is called“double diabetes”(DD).However,knowledge regarding the relationship between DD features and the HGI in T1D is limited.AIM To assess the association between the HGI and DD features in adults with T1D.METHODS A total of 83 patients with T1D were recruited for this cross-sectional study.Laboratory HbA1c and GMI from continuous glucose monitoring data were collected to calculate the HGI.DD features included a family history of type 2 diabetes,overweight/obesity/central adiposity,hypertension,atherogenic dyslipidemia,an abnormal percentage of body fat(PBF)and/or visceral fat area(VFA)and decreased estimated insulin sensitivity.Skin autofluorescence of advanced glycation end products(SAF-AGEs),diabetic complications,and DD features were assessed,and their association with the HGI was analyzed.RESULTS A discrepancy was observed between HbA1c and GMI among patients with T1D and DD.A higher HGI was associated with an increased number of SAF-AGEs and a higher prevalence of diabetic microangiopathy(P=0.030),particularly retinopathy(P=0.031).Patients with three or more DD features exhibited an eight-fold increased risk of having a high HGI,compared with those without DD features(adjusted odds ratio=8.12;95%confidence interval:1.52-43.47).Specifically,an elevated PBF and/or VFA and decreased estimated insulin sensitivity were associated with high HGI.Regression analysis identified estimated insulin sensitivity and VFA as factors independently associated with HGI.CONCLUSION In patients with T1D,DD features are associated with a higher HGI,which represents a trend toward excessive glycosylation and is associated with a higher prevalence of chronic diabetic complications. 展开更多
关键词 Type 1 diabetes double diabetes Insulin resistance Hemoglobin glycation index Advanced glycation end products Diabetic complications
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Analysis of wind-induced vibration response characteristics of multispan double-layer cable photovoltaic support structure 被引量:2
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作者 ZOU Lianghao WANG Jian +2 位作者 SONG Jie ZHOU Rui WANG Hao 《Journal of Southeast University(English Edition)》 2025年第1期37-43,共7页
To investigate the wind⁃induced vibration re⁃sponse characteristics of multispan double⁃layer cable photo⁃voltaic(PV)support structures,wind tunnel tests using an aeroelastic model were carried out to obtain the wind⁃... To investigate the wind⁃induced vibration re⁃sponse characteristics of multispan double⁃layer cable photo⁃voltaic(PV)support structures,wind tunnel tests using an aeroelastic model were carried out to obtain the wind⁃induced vibration response data of a three⁃span four⁃row double⁃layer cable PV support system.The wind⁃induced vibration characteristics with different PV module tilt angles,wind speeds,and wind direction angles were analyzed.The results showed that the double⁃layer cable large⁃span flexible PV support can effectively control the wind⁃induced vibration response and prevent the occur⁃rence of flutter under strong wind conditions.The maxi⁃mum value of the wind⁃induced vibration displacement of the flexible PV support system occurs in the windward first row.The upstream module has a significant shading effect on the downstream module,with a maximum effect of 23%.The most unfavorable wind direction angles of the structure are 0°and 180°.The change of the wind direction angle in the range of 0°to 30°has little effect on the wind vi⁃bration response.The change in the tilt angle of the PV modules has a greater impact on the wind vibration in the downwind direction and a smaller impact in the upwind di⁃rection.Special attention should be paid to the structural wind⁃resistant design of such systems in the upwind side span. 展开更多
关键词 double⁃layer cable photovoltaic support aero⁃elastic model wind tunnel test wind⁃induced vibration re⁃sponse
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Double-Double铺层复合材料C型梁变厚度减重优化
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作者 何靓 李尧 +4 位作者 王思源 霍玥玥 张璇 元振毅 常正平 《复合材料学报》 北大核心 2025年第10期6073-6083,共11页
碳纤维增强树脂基复合材料已经成为航空、航天等领域的重要工程材料。然而,传统复合材料的铺层设计效率低、丢层设计复杂,导致复合材料构件存在一定的设计强度冗余和结构超重。Double-Double作为一种全新的复合材料铺层方法,具有铺层设... 碳纤维增强树脂基复合材料已经成为航空、航天等领域的重要工程材料。然而,传统复合材料的铺层设计效率低、丢层设计复杂,导致复合材料构件存在一定的设计强度冗余和结构超重。Double-Double作为一种全新的复合材料铺层方法,具有铺层设计简单且丢层减重便捷的优点,已成为铺层设计发展的趋势。本文结合Double-Double铺层方法、ABAQUS参数化建模和应变能理论,对复合材料C型梁进行了减重优化设计,建立的有限元分析模型可有效地显示C型梁的弯曲受力状态。结合有限元分析和试验结果,表明Double-Double构件能够有效替代传统铺层构件,在铺层数目一致时Double-Double铺层C型梁的弯曲刚度和极限载荷分别提高了9.28%和12.34%;针对两个优化后的变厚度Double-Double铺层C型梁,其弯曲刚度和强度不仅未减小,整体质量还分别减少了12.5%和17.5%,实现了减重优化目标。 展开更多
关键词 double-double CFRP C型梁 变厚度铺层 减重优化
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Optimizing University Faculty Teams: Addressing the Talent Mobility Challenges in the Context of “Double First-Class” Initiative
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作者 Shanhong Zhang Yuming Song Hongbo Shi 《教育研究前沿(中英文版)》 2024年第3期1-7,共7页
With the advancement of the“Double First-Class”initiative,universities are increasingly focusing on attracting top-tier talent to enhance faculty quality and strengthen academic disciplines.The blind competition for... With the advancement of the“Double First-Class”initiative,universities are increasingly focusing on attracting top-tier talent to enhance faculty quality and strengthen academic disciplines.The blind competition for high-end talent among universities reflects an overshadowing of academic values by economic considerations,neglecting the growth patterns of top talent and the development laws of higher education.This study investigates and reflects on the real-world challenges of faculty mobility in universities,aiming to provide effective guidance for managing university faculty teams. 展开更多
关键词 double First-class”Initiative Higher Education Institutions Faculty Teams Talent Cultivation
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Application and Discussion on the Training of Innovative Graduate Talent Against the Background of“Double First-Class”Construction
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作者 Lijiang Yu Yunlong Ji 《Journal of Contemporary Educational Research》 2024年第12期150-156,共7页
Against the background of the“double first-class”construction,the training of innovative graduate talent has become an important issue in higher education.This article discusses the importance of the training of top... Against the background of the“double first-class”construction,the training of innovative graduate talent has become an important issue in higher education.This article discusses the importance of the training of top graduate innovative talent,analyzes the status of the training of top graduate innovative talent at home and abroad,and summarizes the current challenges in the training of graduate innovative talent in China.Lastly,this paper proposes relevant reform suggestions in response to problems in the training of innovative graduate talent,which provides important references for improving the quality of innovative graduate training. 展开更多
关键词 double first-class”construction Graduate students Cultivation of innovative talent
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基于Double-RNN模型的电力设备故障定位与检测 被引量:1
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作者 李光华 赵小明 何亚东 《信息技术》 2025年第3期144-150,共7页
研究设计了一个四个步骤的热故障诊断模型:数据预处理、特征提取、设备热故障识别和设备热故障定位。Double-RNN网络模型罗列出数据处理过程并对电力设备的热故障识别进行了深入研究,该模型主要由两层RNN网络构成,分别用于数据特征抽取... 研究设计了一个四个步骤的热故障诊断模型:数据预处理、特征提取、设备热故障识别和设备热故障定位。Double-RNN网络模型罗列出数据处理过程并对电力设备的热故障识别进行了深入研究,该模型主要由两层RNN网络构成,分别用于数据特征抽取和类别预测。结果显示,在平均精度上,Double-RNN为90.06%,优于其他算法,并在检测速度上表现出了优异的实时性。由此可见,Double-RNN网络控制模型在电力设备故障定位与检测方面显示出了优越的性能表现,可以在电力设备的故障定位与检测中被广泛采用。 展开更多
关键词 double-RNN 电力设备 热故障 故障检测
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Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword
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作者 María Norte-Muñoz María Portela-Lomba +9 位作者 Paloma Sobrado-Calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez JoséMCabrera-Maqueda Javier Sierra Manuel Vidal-Sanz María Teresa Moreno-Flores Marta Agudo-Barriuso 《Neural Regeneration Research》 SCIE CAS 2025年第8期2395-2407,共13页
Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic nerve.Still,it is unknown whether olfactory enshea... Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic nerve.Still,it is unknown whether olfactory ensheathing glia also have neuroprotective properties.Olfactory ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion cells.Therefore,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve crush.Olfactory ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive treatments.Anatomical and gene expression analyses were performed.Olfactory bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡmolecules.Allogeneically and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an epimembrane.In axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 days.In these retinas,microglial anatomical activation was higher than after optic nerve crush alone.In intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or immunosuppression.However,neuroprotection of axotomized retinal ganglion cells did not improve with these treatments.The different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables. 展开更多
关键词 cell therapy immune recognition major histocompatibility complex class II(MHCII) neuroprotection olfactory ensheathing glia retinal ganglion cells
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Expert consensus on early orthodontic treatment of class Ⅲ malocclusion 被引量:1
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作者 Xin Zhou Si Chen +30 位作者 Chenchen Zhou Zuolin Jin Hong He Yuxing Bai Weiran Li Jun Wang Min Hu Yang Cao Yuehua Liu Bin Yan Jiejun Shi Jie Guo Zhihua Li Wensheng Ma Yi Liu Huang Li Yanqin Lu Liling Ren Rui Zou Linyu Xu Jiangtian Hu Xiuping Wu Shuxia Cui Lulu Xu Xudong Wang Songsong Zhu Li Hu Qingming Tang Jinlin Song Bing Fang Lili Chen 《International Journal of Oral Science》 2025年第3期328-340,共13页
The prevalence of Class Ⅲ malocclusion varies among different countries and regions. The populations from Southeast Asian countries (Chinese and Malaysian) showed the highest prevalence rate of 15.8%, which can serio... The prevalence of Class Ⅲ malocclusion varies among different countries and regions. The populations from Southeast Asian countries (Chinese and Malaysian) showed the highest prevalence rate of 15.8%, which can seriously affect oral function, facial appearance, and mental health. As anterior crossbite tends to worsen with growth, early orthodontic treatment can harness growth potential to normalize maxillofacial development or reduce skeletal malformation severity, thereby reducing the difficulty and shortening the treatment cycle of later-stage treatment. This is beneficial for the physical and mental growth of children. Therefore,early orthodontic treatment for Class Ⅲ malocclusion is particularly important. Determining the optimal timing for early orthodontic treatment requires a comprehensive assessment of clinical manifestations, dental age, and skeletal age, and can lead to better results with less effort. Currently, standardized treatment guidelines for early orthodontic treatment of Class Ⅲ malocclusion are lacking. This review provides a comprehensive summary of the etiology, clinical manifestations, classification, and early orthodontic techniques for Class Ⅲ malocclusion, along with systematic discussions on selecting early treatment plans. The purpose of this expert consensus is to standardize clinical practices and improve the treatment outcomes of Class Ⅲ malocclusion through early orthodontic treatment. 展开更多
关键词 reducing difficulty shortening trea normalize maxillofacial development Early orthodontic treatment Southeast Asian countries classⅢmalocclusion orthodontic treatment Prevalence reduce skeletal malformation severitythereby
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Tunable Topological Floquet Bound States in the Continuum in a Periodically Driven Double SSH Chain
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作者 Xian Duan Ruozhen Wang +3 位作者 Bo Zhu Zhi Tan Honghua Zhong Shu Chen 《Chinese Physics Letters》 2025年第9期77-87,共11页
We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrief... We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrieffer-Heeger chains.The formation of topological Floquet BICs can be adjusted only by tuning the driving amplitude or frequency,regardless of whether the static system has BICs or not.The interchain bias can only change the localization property of topological Floquet BICs,and a bigger bias can lead to transforming topological Floquet BICs into bound states out of the continuum(BOCs).But it does not change the topological properties of these topological Floquet states.Based on the repulsion effect of edge states,we propose to detect occurrence of topological Floquet BICs and transition point between topological Floquet BICs and BOCs using quantum walk.Our work provided a convenient and realistic approach for the experimental realization and manipulation of BICs in a single-particle quantum system. 展开更多
关键词 generate manipulate topological floquet bound states static system CONTINUUM double SSH chain class systems interchain bias floquet bicsand tunable topological floquet bound states
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On the Occurrence of Different Classes of Solar Flares during the Solar Cycles 23 and 24
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作者 Longo Wilfried Sanon Wendpuiré Ousmane Compaoré +1 位作者 Somaïla Koala Jean Louis Zerbo 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期28-38,共11页
In this study we review the occurrence of different types (A, B, C, M, and X classes) of solar flares during different solar cycle phases from 1996 to 2019 covering the solar cycles 23 and 24. During this period, a to... In this study we review the occurrence of different types (A, B, C, M, and X classes) of solar flares during different solar cycle phases from 1996 to 2019 covering the solar cycles 23 and 24. During this period, a total of 19,126 solar flares were observed regardless the class: 3548 flares in solar cycle 23 (SC23) and 15,668 flares in solar cycle 24 (SC24). Our findings show that the cycle 23 has observed the highest occurrences of M-class and X-class flares, whereas cycle 24 has pointed out a predominance of B-class and C-class flares throughout its different phases. The results indicate that the cycle 23 was magnetically more intense than cycle 24, leading to more powerful solar flares and more frequent geomagnetic storms, capable of generating significant electromagnetic emissions that can affect satellites and GPS signals. The decrease in intense solar flares during cycle 24 compared to cycle 23 reflects an evolution in solar activity patterns over time. 展开更多
关键词 Solar Flare Solar Cycle Solar Cycle Phase Solar Flare class OCCURRENCE
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老年心脏病病人工具性日常生活活动能力评估及其相关因素研究--基于CLASS数据
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作者 杨文艳 罗丽红 《循证护理》 2025年第15期3186-3190,共5页
目的:探索我国60岁以上心脏病病人的工具性日常生活活动能力(IADL)现状及其影响因素。方法:通过2020年中国老年社会追踪调查(CLASS)数据,采用简易IADL量表测量老年心脏病病人的IADL,分析老年心脏病病人的IADL在不同特征对象中的差异,多... 目的:探索我国60岁以上心脏病病人的工具性日常生活活动能力(IADL)现状及其影响因素。方法:通过2020年中国老年社会追踪调查(CLASS)数据,采用简易IADL量表测量老年心脏病病人的IADL,分析老年心脏病病人的IADL在不同特征对象中的差异,多因素Logistic回归分析用于进一步探索老年心脏病病人IADL的影响因素。结果:纳入老年心脏病病人1515例,549例(36.24%)病人IADL受损;多因素Logistic回归分析结果显示,年龄、身体健康状况、脑血管疾病、简易精神状态量表(MMSE)评分、家人去世等是老年心脏病病人IADL的影响因素。结论:老年心脏病病人IADL受损较为严重,在未来老年心脏病病人的临床照护和健康管理中需要了解不同人员的特征,重视老年心脏病病人的IADL评估,强化老年心脏病病人的日常活动能力,改善老年心脏病病人的生活质量,促进健康老龄化。 展开更多
关键词 老年人 心脏病 工具性日常生活活动能力 评估 影响因素 class
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Perfect Double Roman Domination on Cographs
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作者 LI Peng XUE Xin-yi +1 位作者 LONG Yang-jing LI Xue-bo 《Chinese Quarterly Journal of Mathematics》 2025年第2期158-168,共11页
Consider a graph G=(V,E).A perfect double Roman dominating function(PDRDF for short)is a function h:V→{0,1,2,3}that satisfies the condition∑_(y∈NG[x],h(y)≥1)h(y)=|{y∈NG(x):h(y)≥1}|+2 for any x∈V with h(x)≤1.Th... Consider a graph G=(V,E).A perfect double Roman dominating function(PDRDF for short)is a function h:V→{0,1,2,3}that satisfies the condition∑_(y∈NG[x],h(y)≥1)h(y)=|{y∈NG(x):h(y)≥1}|+2 for any x∈V with h(x)≤1.The weightω(h)of this function is∑_(y∈V)h(y).The perfect double Roman domination number(PDRD-number)of G,denoted byγ_(dR)^(p)(G),is defined as the minimum weight among all PDRDFs of G.This article presents a comprehensive analysis of the PDRD-number of connected cographs,demonstrating that it falls within the set{2,3,4,5,6}.Furthermore,it establishes that for any integer i≥7,there is a connected cograph G such that its PDRD-number is equal to i. 展开更多
关键词 COGRAPHS double Roman domination Perfect double Roman domination
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Double response reversible phosphorescence based on cyclodextrin supramolecular flexible elastic achieved multicolor delayed fluorescence
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作者 Linnan Jiang Zhenkai Qian +7 位作者 Yong Chen Xiaoyong Yu Yugui Qiu Wen-Wen Xu Yonghui Sun Xiufang Xu Lihua Wang Yu Liu 《Chinese Chemical Letters》 2025年第8期315-321,共7页
Purely organic room-temperature phosphorescence(RTP)is current hotspot in the research fields of chemistry,biology,materials etc.Herein,we report that photo-thermal double response reversible ultralong RTP flexible el... Purely organic room-temperature phosphorescence(RTP)is current hotspot in the research fields of chemistry,biology,materials etc.Herein,we report that photo-thermal double response reversible ultralong RTP flexible elastic material with multicolor delayed fluorescence,which is constructed by 4-biphenylboronic acid(BOH),polyethylene glycol,2,2-bis(hydroxymethyl)propionic acid,isophorone diamine and isophorone diisocyanate copolymer.Importantly,the supramolecular phosphorescent elastomer not only exhibits extending RTP emission with a lifetime up to 1.21 s,but also gives a visible afterglow of 20 s via encapsulation of BOH unities by the deep cavities of hydroxypropyl-β-cyclodextrin(β-CD-HP)and in situ polymerization.Especially,after doping organic dyes(Fluorescein isothiocyanate,Sulforhodamine 101,Rhodamine B),supramolecular phosphorescent elastomer achieves multicolor delayed fluorescence realized by RTP energy transfer from phosphorescent donor to dye acceptors,which possesses reversible photo-thermal responsiveness and maintains high efficiency in delayed emission even after dozens of cycles.Present research provides a new approach for constructing multicolor delayed fluorescent supramolecular elastomers. 展开更多
关键词 double response reversible CYCLODEXTRIN RTP Host-vipinteraction Flexibleelastic
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Double-vacancy-induced polarization and intensified built-in electric field in S-Scheme heterojunction for removal of antibiotics and Cr (VI)
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作者 Xiangyang Zheng Jinwang Wu Haifeng Shi 《Chinese Journal of Catalysis》 2025年第9期50-64,共15页
Antibiotics and heavy metals usually co-exist in wastewater and pose serious environmental hazards.Herein,a series of VMo-BMO/O_(v)-BOB S-scheme heterojunctions with double vacancy(Mo vacancy and photoexcited O vacanc... Antibiotics and heavy metals usually co-exist in wastewater and pose serious environmental hazards.Herein,a series of VMo-BMO/O_(v)-BOB S-scheme heterojunctions with double vacancy(Mo vacancy and photoexcited O vacancy)were constructed via an electrostatic assembly method.The removal efficiency of Cr(VI)and tetracycline(TC)over VMo-BMO/O_(v)-BOB-0.3 was 2.47 and 1.13 times than that of a single system,respectively.In-situ EPR demonstrated that the surface O vacancies could be generated under LED light irradiation.These photoexcited O vacancies(P-O_(v))enabled VMo-BMO/O_(v)-BOB composites still exhibit satisfactory activity after five successive cycles and an amplified Fermi level gap.The enhancement could be attributed to the enhanced internal electric field and double-vacancy-induced polarization.Additionally,the density functional theory calculation results suggested that double vacancy induced polarization electric field increases the dipole moment,which was conducive to rapid electron transport.Photoluminescence and time-resolved photoluminescence analysis demonstrated that the introduction of S-scheme heterojunction and double vacancy promoted charge transfer and prolonged the lifetime of carriers.Degradation intermediates and toxicity of products were evaluated.In conclusion,a possible mechanism based on VMo-BMO/O_(v)-BOB S-scheme heterojunction in the simultaneous removal of Cr(VI)and TC was proposed. 展开更多
关键词 Photocatalysis S-scheme heterojunction double vacancy Polarization Fermi level
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