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储能型MMC一体化补偿装置控制策略研究

制造业自动化 2024年第4期46卷 118-122页

作者：吴显潘迪汪清南方电网公司新型智慧城市高品质供电联合实验室(深圳供电局有限公司) 深圳518020 安徽大学电气工程与自动化学院合肥230601

超级电容储能型MMC补偿装置对配电网中由于不确定性负荷造成的功率波动,三相不平衡等电能质量问题有着较好的治理效果。基于准PR电流控制策略建立了相应的系统模型;介绍了主电路和DC/DC变换电路的调制策略,并基于伏秒平衡/安秒平衡原理... 详细信息

超级电容储能型MMC补偿装置对配电网中由于不确定性负荷造成的功率波动,三相不平衡等电能质量问题有着较好的治理效果。基于准PR电流控制策略建立了相应的系统模型;介绍了主电路和DC/DC变换电路的调制策略,并基于伏秒平衡/安秒平衡原理求出了DC/DC电路开关管的调制比。当超级电容储能型MMC在进行电能质量治理时,其能量流动是否合理对其直流侧电压的控制至关重要,故对其交、直流侧的功率平衡作了相关分析。最后搭建仿真,对理论进行了仿真验证。

关键词：超级电容储能 DC/DC变换电路准PR控制功率平衡

Dynamic Recrystallization Behavior and Processing Map Development of 25CrMo4 Mirror Plate Steel During Hot Deformation

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Acta Metallurgica Sinica(English letters) 2017年第9期30卷 907-920页

作者： Peng Zhou qing.xian Ma Department of Mechanical Engineering TsinghuaUniversityBeijing 100084China Key laboratory for Advanced Materials ProcessingTechnology of Ministry of Education Tsinghua University Beijing 100084China

The dynamic recrystallization behavior of 25CrMo4 steel was systematically investigated by compression deformation at different temperatures and strain rates on a Gleeble 1500 thermal mechanical simulation tester. The flow curves under different deformation conditions were obtained, and the effects of deformation temperature and strain rate on the appearance of the flow curves were discussed. Based on the experimental flow curves, the activation energy determined by regression analysis was Q = 337 kJ/mol, and the constitutive model was constructed. All the characteristic points of the flow curves were identified from the work hardening rate curves （θ= dσ/dε vs σ）, which were derived from the flow curves. Then, the kinetics model of dynamic recrystallization was determined by combining the Avrami equation with the stress loss resulted from the dynamic recrystallization. With the aid of the kinetics model, the effect of strain on the efficiency of power dissipation was discussed. Furthermore, the optimum parameters for the forging process were determined based on the processing maps.

关键词： 25CrMo4 steel Dynamic recrystallization Kinetics model Processing map

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双层圆柱壳在均匀轴压下的屈曲行为

舰船科学技术 2024年第2期46卷 15-22页

作者：聂露清王黎辉唐文献江苏科技大学机械工程学院江苏镇江2120001

对双层不锈钢圆柱壳在均匀轴压下的屈曲性能进行研究,分别设计、制作和测量了3个名义相同的双层圆柱薄壳,其长径比均为1.7。通过对试样进行轴向压缩试验获得其载荷位移曲线和极限强度,采用弧长法对试样进行非线性屈曲分析,得到平衡曲线... 详细信息

对双层不锈钢圆柱壳在均匀轴压下的屈曲性能进行研究,分别设计、制作和测量了3个名义相同的双层圆柱薄壳,其长径比均为1.7。通过对试样进行轴向压缩试验获得其载荷位移曲线和极限强度,采用弧长法对试样进行非线性屈曲分析,得到平衡曲线和临界载荷并与试验结果进行对比。另外采用数值分析法研究双层圆柱壳的缺陷敏感性,进而推测出一种用于评估双层圆柱壳承载能力的理论公式。结果表明,双层圆柱壳的平均极限强度约为单层的1.85倍,双层圆柱壳是缺陷敏感结构,其缺陷敏感性与内层壳体缺陷敏感性趋于一致,且双层圆柱壳的缺陷敏感性随长径比的增加而降低,试验结果、数值计算和理论预测具有较高一致性。

关键词：轴向压缩双层圆柱壳屈曲分析缺陷敏感性

Resilient and Safe Platooning Control of Connected Automated Vehicles Against Intermittent Denial-of-Service Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1234-1251页

作者： Xiaohua Ge qing-long Han qing Wu xian-Ming Zhang the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the School of Engineering and Technology Central Queensland UniversityRockhampton QLD 4701Australia

Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on *** paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle ***,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon ***,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and ***,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain ***,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.

关键词： Connected automated vehicles(CAVs) cooperative adaptive cruise control denial-of-service(DoS)attacks resilient control vehicle platooning vehicle-to-vehicle communication

HPlC法同时测定脑脉泰胶囊中12种成分的含量

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中成药 2024年第7期46卷 2147-2152页

作者：高俊卿程仙送于叔麒张妮陕西省人民医院神经内一科陕西西安710068 西安交通大学第二附属医院康复医学科陕西西安710004

目的建立HPlC法同时测定脑脉泰胶囊中3′-羟基葛根素、2-羟基红花黄色素A、葛根素、葛根素芹菜糖苷、3′-甲氧基葛根素、大豆苷、二苯乙烯苷、木犀草苷、染料木苷、木犀草素、丹酚酸B、迷迭香酸的含量。方法分析采用KromasilC_(18)色谱... 详细信息

目的建立HPlC法同时测定脑脉泰胶囊中3′-羟基葛根素、2-羟基红花黄色素A、葛根素、葛根素芹菜糖苷、3′-甲氧基葛根素、大豆苷、二苯乙烯苷、木犀草苷、染料木苷、木犀草素、丹酚酸B、迷迭香酸的含量。方法分析采用KromasilC_(18)色谱柱(250mm×4.6mm,5μm);流动相乙腈-水(含1.0g/l磷酸),梯度洗脱;体积流量0.8ml/min;柱温30℃;检测波长280nm。再进行聚类分析、主成分分析。结果12种成分在各自范围内线性关系良好(r>0.9990),平均加样回收率97.07%~98.30%,RSD0.86%~1.82%。10批样品聚为4类,4种主成分累积方差贡献率达86.262%。结论该方法简便稳定,可靠准确,可为脑脉泰胶囊的质量控制提供科学依据。

关键词：脑脉泰胶囊化学成分含量测定 HPlC 聚类分析主成分分析

Effect and Safety of Herbal Medicine Foot Baths in Patients with Diabetic Peripheral Neuropathy:A Multicenter Double-Blind Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2024年第3期30卷 195-202页

作者： HUANG Hao-yue lIN Yu-ping WEI Hua FU Yu ZHOU Yue-hong FANG Zhao-hui QIU Xiao-tang WANG Mei lI qing-bo lI Shan-shan WANG Shi-dong DAI Fang lIU Zhen-jie ZHAO ling WEN Jian-xuan WU li-yan ZENG Hui-yan ZHANG Jin-ming lU Qi-yun HE liu SONG Wei SUN lu lUO lu-lu HE Jia-li XIE Wen-wen lIANG qing-shun HUANG Yuan ZHU Sheng-ling lONG Jie-er GAO Zhi-juan WEN Ze-huai lI Chun-ji OUYANG Wen-wei lI Geng WU Ming-hui lI An-xiang HUANG Jin-zhu Sanjoy K Paul TANG xian-yu FAN Guan-jie Department of Endocrinology Guangdong Provincial Hospital of Chinese MedicineGuangzhou510120China The Second Clinical College of Guangzhou University of Chinese Medicine Guangzhou510120China Department of Endocrinology The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou510120China Guangdong Provincial Academy of Chinese Medical Sciences Guangzhou510120China Department of Endocrinology The First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou450000China Department of Endocrinology Liuyang Hospital of Chinese MedicineChangsha410000China Department of Endocrinology The First Affiliated Hospital of Anhui University of Chinese MedicineHefei230000China Department of Endocrinology Hainan Provincial Hospital of Traditional Chinese MedicineHaikou570100China Department of Endocrinology The Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang110000China Department of Geriatric Luoyang No.1 Hospital of Traditional Chinese MedicineLuoyangHenan Province471000China Department of Endocrinology The Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang550000China Department of Endocrinology Beijing University of Chinese Medicine Affiliated Dongzhimen HospitalBeijing100000China Department of Endocrinology The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang550000China Melbourne EpiCentre The University of Melbourne and Melbourne HealthMelbourne3013Australia

Objective:To evaluate the effect and safety of foot baths with Tangbi Waixi Decoction(TW)in treating patients with diabetic peripheral neuropathy(DPN).Methods:It is a multicenter double-blinded randomized controlled *** with DPN were recruited between November 18,2016 and May 30,2018 from 8 hospitals in *** patients received basic treatments for glycemic *** received foot baths with TW herbal granules either 66.9 g(intervention group)or 6.69 g(control group)for 30 min once a day for 2 weeks and followed by a 2-week rest,as a therapeutic *** the Toronto Clinical Scoring System total score(TCSS-TS)6 points,the patients received a total of 3 therapeutic courses(for 12 weeks)and were followed up for 12 *** primary outcome was change in TCSS-TS score at 12 and 24 *** outcomes included changes in bilateral motor nerve conduction velocity(MNCV)and sensory nerve conduction velocity(SNCV)of the median and common peroneal *** was also ***:Totally 632 patients were enrolled,and 317 and 315 were randomized to the intervention and control groups,*** the 12-week intervention,patients in both groups showed significant declines in TCSSTS scores,and significant increases in MNCV and SNCV of the median and common peroneal nerves compared with pre-treatment(Pl group were greater than those in the intervention group(Ply between groups(P>0.05),and no serious adverse event was related with ***:Treatment of TW foot baths was safe and significantly benefitted patients with DPN.A low dose of TW appeared to be more effective than a high dose.(Registry *** CTR-IOR-16009331)

关键词： diabetic peripheral neuropathy herbal medicine foot baths Chinese medicine randomized controlled trial Tangbi Waixi Decoction

海洋背景涡度对台风康森引起的近惯性波的影响研究

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海洋与湖沼 2024年第3期55卷 589-598页

作者：郑晓婷曹安州吕咸青宋金宝浙江大学海洋学院浙江舟山316021 中国海洋大学海洋与大气学院山东青岛266100

近惯性波是海洋中普遍存在的一种内波,它在海洋中的传播和耗散受到背景涡度的影响。基于混合坐标海洋模型(hybrid coordinate ocean model,HYCOM)再分析数据,研究了海洋背景正、负涡度对台风康森在南海引起的近惯性波的不同影响。结果表... 详细信息

近惯性波是海洋中普遍存在的一种内波,它在海洋中的传播和耗散受到背景涡度的影响。基于混合坐标海洋模型(hybrid coordinate ocean model,HYCOM)再分析数据,研究了海洋背景正、负涡度对台风康森在南海引起的近惯性波的不同影响。结果表明:负涡度能捕捉并促进近惯性能量向海洋深层的传播,可传播到1200 m以深;而正涡度则阻碍近惯性能量的下传,使其主要集中在海洋上层500 m以内。负涡度区域能维持较强的近惯性能量10 d以上,而正涡度区域内的近惯性能量维持时间在1周左右。负涡度区域内的近惯性波由第二和第三模态主导,而正涡度区域内的近惯性波由第一和第二模态主导,导致海洋内部(500~1000 m)负涡度区域内的近惯性波剪切比正涡度区域内的近惯性波剪切强1~2个量级。波射线模型模拟结果显示,近惯性波在负涡度区域边缘发生反射,进而被负涡度区域捕获;而正涡度区域内的近惯性波有加速远离源地的趋势。上述结果进一步说明,海洋背景负涡度能增强近惯性能量的垂向传播,而正涡度则促进了近惯性能量的水平传播。

关键词：海洋背景涡度近惯性波混合坐标海洋模型再分析数据波射线模型

Antibacterial,antioxidant and antiproliferation activities of essential oils and ethanolic extracts from Chinese mugwort(Artemisia vulgaris l.)leaf in Shanxi

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Traditional Medicine Research 2024年第1期9卷 47-56页

作者： Hu-Tan-xian Zhang Feng-Ru lyu Jia-Tong He Chen-Yu liu Zheng-Yang Zhou Rui-Jie Wu Zi-qing Zhao He li School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Shanxi Jinshuo Biomedical Technology Co. Ltd.Jinzhong 030600China

Background:Artemisia vulgaris,a medicinal aromatic plant,is widely used as a food item,tonic pharmaceutical,and cosmetic industry additive owing to its antibacterial,antihypertensive,hepatoprotective,antioxidant,and antispasmodic *** the effect of different geographic locations on the chemical composition and bioactivities of its extracts is ***:Biological activities of essential oils and ethanol extracts of three varieties of Artemisia vulgaris leaves,which are grown in Shanxi province China,were ***:Gas chromatography-mass spectrometry analysis revealed that the main components of essential oils were terpenes and *** oils and ethanol extract of Artemisia vulgaris leaves possessed good antioxidant activities,and their half maximal inhibitory concentrations determined using 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate)assays were 57.0 and 22.9μg/ml,*** essential oils also exhibited remarkable antibacterial activity against three foodborne pathogenic bacterial *** ethanol extract presented a high anticancer activity against the MGC-803 human gastric cancer cell ***:These biological activities were well correlated with the composition of the extract and EOs,which in turn is affected by the genetic composition of Artemisia vulgaris and geographic location and diverse climatic condition under which it is *** findings demonstrate the remarkable potential of Artemisia vulgaris as a valuable source of antioxidant,antibacterial,and anticancer agents.

关键词： Artemisia vulgaris essential oils ethanol extracts antioxidant antiproliferation

Novel Stability Criteria for linear Time-Delay Systems Using lyapunov-Krasovskii Functionals With A Cubic Polynomial on Time-Varying Delay

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 77-85页

作者： xian-Ming Zhang qing-long Han Xiaohua Ge the School of Software and Electrical Engineering Swinburne University of TechnologyMelbourneVIC 3122Australia

One of challenging issues on stability analysis of time-delay systems is how to obtain a stability criterion from a matrix-valued polynomial on a time-varying *** first contribution of this paper is to establish a necessary and sufficient condition on a matrix-valued polynomial inequality over a certain closed *** degree of such a matrix-valued polynomial can be an arbitrary finite positive *** second contribution of this paper is to introduce a novel lyapunovKrasovskii functional,which includes a cubic polynomial on a time-varying delay,in stability analysis of time-delay *** on the novel lyapunov-Krasovskii functional and the necessary and sufficient condition on matrix-valued polynomial inequalities,two stability criteria are derived for two cases of the time-varying delay.A well-studied numerical example is given to show that the proposed stability criteria are of less conservativeness than some existing ones.

关键词： Bessel-legendre inequality matrix-valued polynomial inequalities stability time-varying delay time-delay systems