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RL and AHP-Based Multi-Timescale Multi-Clock Source Time Synchronization for Distribution Power Internet of Things

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Computers, Materials & Continua 2024年第3期78卷 4453-4469页

作者： Jiangang Lu Ruifeng Zhao Zhiwen Yu yue dai Kaiwen Zeng Electric Power Dispatching and Control Center Guangdong Power Grid Co.Ltd.Guangzhou510600China

Time synchronization(TS)is crucial for ensuring the secure and reliable functioning of the distribution power Internet of Things(IoT).Multi-clock source time synchronization(MTS)has significant advantages of high reliability and accuracy but still faces challenges such as optimization of the multi-clock source selection and the clock source weight calculation at different timescales,and the coupling of synchronization latency jitter and pulse phase *** this paper,the multi-timescale MTS model is conducted,and the reinforcement learning(RL)and analytic hierarchy process(AHP)-based multi-timescale MTS algorithm is designed to improve the weighted summation of synchronization latency jitter standard deviation and average pulse phase ***,the multi-clock source selection is optimized based on Softmax in the large timescale,and the clock source weight calculation is optimized based on lower confidence bound-assisted AHP in the small *** shows that the proposed algorithm can effectively reduce time synchronization delay standard deviation and average pulse phase difference.

关键词： Multi-clock source time synchronization(TS) power Internet of Things reinforcement learning analytic hierarchy process

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian Chen Hao-Chen Song Lu-Yu Zhong yue-Xiang dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

The Role of Renewable Protocatechol Acid in Epoxy Coating Modification: Significantly Improved Antibacterial and Adhesive Properties

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Chinese Journal of Polymer Science 2024年第1期42卷 63-72,I0008页

作者： Ming-Xuan Chen Jin-yue dai Li-yue Zhang Shuai-Peng Wang Jing-Kai Liu Yong-Gang Wu Xin-Wu Ba Xiao-Qing Liu School of Chemistry and Materials Science Hebei UniversityBaoding 071000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Marine Materials and Related Technologies Chinese Academy of SciencesNingbo 315201China

It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(EGDE) through an efficient, and green method, and it was cured with isophorone diamine(IPDA) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against E. coli and S. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques.

关键词： Epoxy coatings Thermosets Catechol structure Antibacterial High adhesion

Association of Serum Folate and Vitamin B_(12) Concentrations with Obesity in Chinese Children and Adolescents

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Biomedical and Environmental Sciences 2024年第3期37卷 242-253页

作者： ZHU Qian Rang KOK E Dieuwertje BEKELE Hailu Tesfaye MANUSAMA Koen ZHANG Jing Xian XIE Wei ZONG Wen Qi ZUO Hui ZHANG Jian KAMPMAN Ellen dai yue Jiangsu Provincial Center for Disease Control and Prevention Nanjing 210009JiangsuChina Division of Human Nutrition and Health Wageningen University&ResearchWageningen 176700 AAThe Netherlands School of Public Health Medical College of Soochow UniversitySuzhou 215123JiangsuChina National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China

Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and *** A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,*** indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were *** linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of *** We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)=0.68;95%confidence interval(CI)=0.59,0.78]and abdominal obesity(OR=0.68;95%CI=0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR=0.31,95%CI=0.19,0.50)or abdominal obesity(OR=0.46,95%CI=0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR=2.06,95%CI=1.09,3.91).Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood *** and adolescents with high levels of vitamin B12 and folate were less likely to be obese.

关键词： Folate Vitamin B12 Childhood obesity Micronutrient

Advances in the Mechanisms of Hemorrhagic Transformation and Therapeutic Agents after Intravenous Thrombolysis in Ischemic Stroke

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Yangtze Medicine 2024年第1期8卷 29-40页

作者： yue dai Yongyi Zhan Mingtian Lu Zehua He Yu Liu Zhuhai Clinical Medical College of Jinan University (Zhuhai People’s Hospital) Zhuhai China

Ischemic stroke is an important disease leading to death and disability for all human beings, and the key to its treatment lies in the early opening of obstructed vessels and restoration of perfusion to the local infarcted area. Intravenous thrombolysis with tissue plasminogen activator (tPA) is one of the effective therapies to achieve revascularization, but it faces strict indications with a narrow therapeutic time window, and significantly increases the incidence of hemorrhagic transformation, HT, after reperfusion of the infarcted foci, which greatly reduces the incidence of patients with ischemic stroke. which significantly increases the incidence of hemorrhagic transformation (HT) after reperfusion of the infarcted focus, greatly reducing patient utilization and clinical benefit. Since the mechanism of HT has not been fully elucidated, and the related molecular mechanisms are complex and interactive, there is no specific and effective therapy to avoid the occurrence of HT. In this article, we focus on the research progress on the mechanism of HT after tPA intravenous thrombolysis in ischemic stroke patients from the aspects of vascular integrity disruption, oxidative stress, and neuroinflammatory response and the corresponding therapeutic strategies, in order to improve the safety and prognosis of tPA intravenous thrombolysis in the clinic.

关键词： Hemorrhagic Transformation Tissue-Type Fibrinogen Activator Acute Ischemic Stroke Blood-Brain Barrier

细胞膜电压振荡对脊髓中间神经元节律性放电的调控作用

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中国医学物理学杂志 2024年第5期41卷 610-615页

作者：陈玥如戴跃华东师范大学通信与电子工程学院上海200241

为了探究细胞膜振荡状态下离子通道对脊髓中间神经元节律信号的影响,建立了两个猫脊髓中间神经元模型,它们通过交互式抑制的方式相互连接,当受到兴奋刺激时模型能够产生节律性放电。运用该模型,研究了突触输入下白噪音(WN组)、离子通道... 详细信息

为了探究细胞膜振荡状态下离子通道对脊髓中间神经元节律信号的影响,建立了两个猫脊髓中间神经元模型,它们通过交互式抑制的方式相互连接,当受到兴奋刺激时模型能够产生节律性放电。运用该模型,研究了突触输入下白噪音(WN组)、离子通道插入振荡因子(CF组)、以及白噪音与振荡因子同时作用(WN+CF组)3种条件下,神经元模型的兴奋性与运动节律的变化规律,定量化描述中间神经元节律性放电的电压阈值、步进占空比以及瞬时放电频率变化的规律。仿真结果表明,(1)WN组、CF组、WN+CF组电压阈值分别为-46.98、-46.48、-47.00 mV;与控制组相比,WN组和WN+CF组的电压阈值分别降低了0.47和0.49 mV,CF组提高了0.03 mV;(2)WN组、CF组和WN+CF组屈肌和伸肌的瞬时放电频率分别为41.01和41.28 Hz、27.45和27.43 Hz、40.20和40.17 Hz;与控制组相比,分别提高了15.20和15.25 Hz、1.64和1.40Hz、14.39和14.14 Hz;(3)WN组、CF组和WN+CF组步进频率分别为0.72、0.68和0.68 Hz;与控制组相比,WN组增加了0.01 Hz,CF组和WN+CF组分别降低了0.03和0.03 Hz;(4)WN组、CF组和WN+CF组步进占空比分别为49.41%、45.02%、50.18%;与控制组相比,WN组和WN+CF组的步进占空比分别增加了4.27%和5.04%,CF组则减少了0.12%。这些结果显示了膜振荡状态下离子通道对神经元兴奋性以及运动节律的调控作用,为后续的生理实验提供了预测和参考。

关键词：膜振荡中间神经元离子通道神经元兴奋性运动节律

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大学如何参与拔尖人才早期培养:美国一流大学的实践经验

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全球教育展望 2024年第6期53卷 74-90页

作者：王正青戴月西南大学教育学部重庆400715

早期培养是拔尖创新人才成长的重要环节。美国一流大学借助其独有的资源优势,积极介入中小学英才教育,参与到拔尖人才早期培养过程中。围绕人才识别、人才培养、学术研究与教师培训四类核心职能,美国一流大学建立了不同类型的英才教育中... 详细信息

早期培养是拔尖创新人才成长的重要环节。美国一流大学借助其独有的资源优势,积极介入中小学英才教育,参与到拔尖人才早期培养过程中。围绕人才识别、人才培养、学术研究与教师培训四类核心职能,美国一流大学建立了不同类型的英才教育中心,并通过确立培养进路、重组课程体系、推动过程贯通、优化质量评估、提供心理支持等路径,构建起拔尖人才早期培养的有效模式。美国各级政府、学术机构、科技公司与公益组织提供了政策、资金、学术、平台等方面的专业支持,建立了卓有成效的支持保障体系。美国拔尖人才的早期培养在人才识别与才能发展等方面优势突出,能够兼顾弱势群体英才教育的机会公平问题,整合多方资源为校内英才教育提供有效补充,通过一流高校间的合作共建国际英才教育网,这些实践经验具有一定镜鉴价值。

关键词：拔尖人才早期培养美国一流大学英才教育中心

GTAW熔池激光条纹动态行为与熔透预测方法研究

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机械工程学报 2024年第6期60卷 236-244页

作者：李春凯王嘉昕石玗代悦兰州理工大学省部共建有色金属先进材料加工与再利用国家重点实验室兰州730050 兰州理工大学温州泵阀工程研究院温州325100

熔透状态是影响焊缝质量的关键因素之一,可靠传感并实时预测焊缝熔透状态对于提升焊接质量以及焊接智能化水平具有非常重要的意义。利用激光视觉法对低频脉冲钨极氩弧焊(Pulsed gas tungsten arc welding,P-GTAW)不同熔透状态下的反射... 详细信息

熔透状态是影响焊缝质量的关键因素之一,可靠传感并实时预测焊缝熔透状态对于提升焊接质量以及焊接智能化水平具有非常重要的意义。利用激光视觉法对低频脉冲钨极氩弧焊(Pulsed gas tungsten arc welding,P-GTAW)不同熔透状态下的反射激光条纹进行了检测,通过建立熔池表面标准模型分析了激光条纹图像动态行为与三种熔透状态熔池自由表面之间(未熔透、临界熔透、全熔透)的相关性,并基于深度学习卷积神经网络建立了GTAW熔透预测模型。研究表明:P-GTAW激光条纹的动态行为与熔池背面熔透状态、熔池表面振荡模式之间存在明确的光学对应关系,所建立从激光条纹图像到GTAW背面熔透状态的端到端卷积神经网络模型能够准确分类未熔透、临界熔透和全熔透三种状态,且分类准确率可达到98.1%,能够实现焊缝熔透状态实时传感及预测。

关键词：熔透检测激光视觉法深度学习熔池振荡端到端神经网络 GTAW

国际食品安全文化建设进展分析及对我国的启示

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食品工业科技 2024年第9期45卷 218-224页

作者：李强张冰岩戴岳张宏蕊刘鹏中国标准化研究院农业食品标准化研究所北京100191

为探索建设适合我国国情的食品安全文化,本文收集整理全球食品安全倡议(GFSI)、世界卫生组织(WHO)、国际食品法典委员会(CAC)及欧盟、澳新、美国、英国等组织和国家开展的食品安全文化建设工作的资料,从食品安全文化的定义、出台的相关... 详细信息

为探索建设适合我国国情的食品安全文化,本文收集整理全球食品安全倡议(GFSI)、世界卫生组织(WHO)、国际食品法典委员会(CAC)及欧盟、澳新、美国、英国等组织和国家开展的食品安全文化建设工作的资料,从食品安全文化的定义、出台的相关政策、建立食品安全文化的重要性、食品安全文化评价原则、应采取的有效措施和评估时使用的工具等方面进行了分析比较,并基于中国传统文化的积淀、传承、城乡食品安全现状,提出了构建中国特色食品安全文化相关建议,希望为构建符合我国国情的食品安全文化提供参考和借鉴。

关键词：食品食品安全文化现代化食品安全价值观评价原则

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