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Partition method for improvement of piecewise linear model with full envelope covered

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航空动力学报 2016年第12期31卷 3042-3053页

作者： YANG Shu-bo WANG Xi LONG Yi-fu LI zhi-peng hu zhong-zhi YIN Kai ZHANG Rong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics Commercial Aircraft Engine Company Limited Aero Engine(Group)Corporation of China

Since ambient conditions vary in a wide range within the full flight envelope,the existing piecewise linear model(PLM),which is based on sea-level static condition with use of corrected parameters for other points in the flight envelope,cannot meet the accuracy for replacing the nonlinear *** obtain more accurate linear models,a method of partitioning the flight envelope over a grid of Mach number and altitude boxes was ***,a set of linear models for a given operating condition was selected by picking the nearest(Mach number,altitude)box in the flight *** the selected set of linear models,interpolating for power level based on a weighted sum of corrected rotor speeds can obtain a linear model with acceptable *** results of different points within the full flight envelope showed that the maximum error between nonlinear model and the existing PLM was more than 50%,while the maximum error between nonlinear model and the improved PLM was within 8%.It is concluded that the improved PLM performs accurately,especially under the non-standard *** addition,the improved PLM can satisfy the real-time requirement better than the existing PLM.

关键词： piecewise linear model partition full envelope parameter schedule turbofan engine

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分数阶低通滤波器的优化设计研究

电子学报 2022年第1期50卷 185-194页

作者：何雪胡志忠南京航空航天大学电子信息工程学院江苏南京211106

分数阶滤波器由于具备连续步进的阻带衰减速率和更大的设计自由度而受到国内外学者的广泛关注.本文提出两种符合指标要求的分数阶低通滤波器的优化设计方法,即采用Matlab优化工具箱中的Fminimax和Fgoalattain两种多目标优化函数来分别... 详细信息

分数阶滤波器由于具备连续步进的阻带衰减速率和更大的设计自由度而受到国内外学者的广泛关注.本文提出两种符合指标要求的分数阶低通滤波器的优化设计方法,即采用Matlab优化工具箱中的Fminimax和Fgoalattain两种多目标优化函数来分别设计符合指标要求的两种不同形式传递函数的分数阶低通滤波器,通过比较通带偏差、阻带偏差以及群时延等参数,总结这两种方法所优化设计的滤波器各自的特点.给出设计实例,对其进行稳定性分析和电路仿真,并搭建电路证明了所提设计方法的有效性.

关键词：分数阶微积分分数阶滤波器优化设计

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一种分数阶巴特沃斯滤波器的有源电路设计

电子学报 2018年第5期46卷 1160-1165页

作者：庞轶环胡志忠南京航空航天大学电子信息工程学院江苏南京211106

本文将分数阶的低通滤波器的传递函数通式近似设计为Butterworth滤波器,在确定阶数与截止频率之后计算得到传递函数的系数.继而,本文通过该传递函数设计电路,进行仿真并电路实现.本文设计的电路在任意阶数下都只需要修改小部分元件便可... 详细信息

本文将分数阶的低通滤波器的传递函数通式近似设计为Butterworth滤波器,在确定阶数与截止频率之后计算得到传递函数的系数.继而,本文通过该传递函数设计电路,进行仿真并电路实现.本文设计的电路在任意阶数下都只需要修改小部分元件便可得到预计截止频率,具有很强的灵活性.

关键词： Butterworth滤波器分数阶微积分分数阶滤波器

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永久振动环境中岩土锚杆适用性的分析和测试

岩土力学 2010年第8期31卷 2599-2603页

作者：胡忠志简文彬台州学院建筑工程学院福建台州318000 福州大学福州350108

对土介质中的全长注浆锚杆进行了固有特性分析,推导了锚杆固有频率和固有振型的计算公式。考虑对永久震动环境中能否设计永久锚杆缺少经验,对所涉及的列车激励场地做了动力测试和频谱分析,以避免使支护构件的自振频率接近该场地中外界... 详细信息

对土介质中的全长注浆锚杆进行了固有特性分析,推导了锚杆固有频率和固有振型的计算公式。考虑对永久震动环境中能否设计永久锚杆缺少经验,对所涉及的列车激励场地做了动力测试和频谱分析,以避免使支护构件的自振频率接近该场地中外界激励的优势频率和介质的一阶卓越频率。研究表明锚杆一阶纵向自振频率、场地卓越频率、列车优势频率分布于不同的频带,列车激励不致造成锚杆的共振。通过这一分析,为进一步认识锚杆支护结构在复杂环境下的适用性问题提供了参考。

关键词：边坡支护锚杆固有特性模态试验基本频率列车振动

Synthesis,Structure and Hydrogenation Property of trans-PdCl2｛Ph2P[o-C6H4CH（OC2H5）2]｝2

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Chemical Research in Chinese Universities 1997年第4期 117-120页

作者： XU Pian pian, GAO Jing xing ** , ZHOU Zhao hui, WANG Jin zhi CHEN zhong, hu Sheng zhi and WAN hui lin (Department of Chemistry, State Key Laboratory for Physical Chemistry of Solid Surface and Institute of Physical Chemistry, Xiamen Univer

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊... 详细信息

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊，ＺＨＯＵＺｈａｏ－ｈｕｉ，ＷＡＮ...

关键词： Palladium complex Hydrogenation Crystal structure

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： zhi-Jun Xie Jia-Lin Li Ling Gong Xiang-Li zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang Yu Rongrong hu Ben zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong AIE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDFA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by F-generated from PDFA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDFA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation

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Neural Regeneration Research 2025年第2期20卷 326-342页

作者： Yi Ji Chaoyi Yang Xuerui Pang Yibing Yan Yue Wu zhi Geng Wenjie hu Panpan hu Xingqi Wu Kai Wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders HefeiAnhui ProvinceChina Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health HefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina Department of Psychology and Sleep Medicine The Second Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina

Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and *** Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients *** transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological *** the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and *** has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological ***,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of *** study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated *** review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s *** mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also ***,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations.

关键词： Alzheimer’s disease amyloid deposition apoptotic mechanisms biomarker neural regeneration neurodegeneration repetitive transcranial magnetic stimulation synaptic plasticity

不同晶粒尺寸Mg掺杂(Ba_(0.6)Sr_(0.4))_(0.925)K_(0.075)TiO_3薄膜的直流场介电性能研究

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功能材料 2007年第11期38卷 1841-1844页

作者：孙小华胡宗智吴敏余本芳赵兴中三峡大学机械与材料工程学院湖北宜昌443002 武汉大学物理科学与技术学院湖北武汉430072

采用溶胶凝胶工艺,在Pt/Ti/SiO2/Si衬底制备了Mg掺杂(Ba0.6Sr0.4)0.925K0.075TiO3(BSKT)薄膜。X射线衍射(XRD)和扫描电镜(SEM)分析测定了物相微结构和薄膜表面形貌,研究了Mg掺杂含量对BSKT晶粒尺寸和直流场介电调谐性能的影响,讨论了直... 详细信息

采用溶胶凝胶工艺,在Pt/Ti/SiO2/Si衬底制备了Mg掺杂(Ba0.6Sr0.4)0.925K0.075TiO3(BSKT)薄膜。X射线衍射(XRD)和扫描电镜(SEM)分析测定了物相微结构和薄膜表面形貌,研究了Mg掺杂含量对BSKT晶粒尺寸和直流场介电调谐性能的影响,讨论了直流场介电损耗谱演变的原因。结果表明,Mg掺杂BSKT使薄膜表面粗糙度、晶粒尺寸、介电常量、介电损耗和调谐量都降低;在室温1MHz下,BSKT薄膜有最大的调谐量73.6%;6%(摩尔分数)Mg掺杂BSKT薄膜有最低的介电损耗为0.0088;发现直流场下薄膜的介电损耗谱演变一方面可能与薄膜的晶粒尺寸有关,另一方面也可能与测试温度有关。

关键词： BSKT Mg掺杂溶胶凝胶介电调谐性能