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GENERALIZED VARIATIONAL OPTI MAZATION ANALYSIS FOR2-D FLOW FIELD

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Journal of Hydrodynamics 2005年第4期17卷 459-465页

作者： HUANG Si-xun XU Ding-hua LAN Wei-ren teng jia-jun Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China LMSWE Nanjing University Nanjing 210093 China LMSWE Nanjing University Nanjing 210093 China East China Technology Institute Fuzhou 344000 China Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China

The Variational Optimization Analysis Method （VOAM） for 2-D flow field suggested by Sasaki was reviewed first. It is known that the VOAM can he used efficiently in most cases. However, in the cases where there are high frequency noises in 2-D flow field, it appears to be inefficient. In the present paper, based on Sasaki＇s VOAM, a Generalized Variational Optimization Analysis Method （GVOAM） was proposed with regularization ideas, which could deal well with flow fields containing high frequency noises. A numerical test shows that observational data can be both variationally optimized and filtered, and therefore the GVOAM is an efficient method.

关键词： variational optimization analysis regularization methods generalized variational optimization analysis

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han jia Tuo Liu Yuzhen Yang jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

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

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资料变分同化中的若干理论问题

应用数学和力学 2007年第5期28卷 581-591页

作者：滕加俊张瑰黄思训上海大学上海市应用数学和力学研究所上海200072 解放军理工大学理学院数理系南京211101

对变分同化中的若干理论问题进行了研究,具体讨论了一类简单模式在整体和局部观测资料下的变分同化问题.对于整体观测资料下的变分同化问题,利用变分同化方法对预报模式中的初值、参数以及模式进行了修正,从理论上作出了变分同化方法的... 详细信息

对变分同化中的若干理论问题进行了研究,具体讨论了一类简单模式在整体和局部观测资料下的变分同化问题.对于整体观测资料下的变分同化问题,利用变分同化方法对预报模式中的初值、参数以及模式进行了修正,从理论上作出了变分同化方法的误差估计及收敛精度的估计,证明了变分同化方法的有效性.对于局部观测资料下的变分同化问题,由于得到的解往往不适定,因而通常的变分同化方法失效.为了克服问题的不适定性所带来的困难,利用变分同化结合正则化方法对预报模式中的初值、参数以及模式进行修正,同样作出了变分同化方法的误差估计及收敛精度估计,证明了变分同化与正则化方法结合的必要性和有效性,并对正则化参数的选择提供了理论判据.最后,举了一个实例说明所提出的方法的有效性.

关键词：变分同化正则化方法收敛精度估计

气管内超声引导下经支气管针吸活检对肺内病变的诊断价值

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中华结核和呼吸杂志 2013年第1期36卷 17-21页

作者：杨会珍滕家俊钟润波张杰孙加源韩宝惠上海交通大学附属胸科医院呼吸内科 200030

目的评价气管内超声引导下的经支气管针吸活检（EBUS—TBNA）对肺内良恶性病变的诊断价值和安全性。方法回顾性分析上海市胸科医院于2009年10月9日至2011年11月30日行EBUS-TBNA检查的78例肺内病变患者，胸部CT检查显示气管、支气管周围... 详细信息

目的评价气管内超声引导下的经支气管针吸活检（EBUS—TBNA）对肺内良恶性病变的诊断价值和安全性。方法回顾性分析上海市胸科医院于2009年10月9日至2011年11月30日行EBUS-TBNA检查的78例肺内病变患者，胸部CT检查显示气管、支气管周围肺内病变的患者行EBUS-TBNA，未采用现场细胞学方法检测，必要时联合免疫组织化学检测进一步完善诊断。结果78例患者中男48例，女30例，年龄25～80岁，中位年龄为58岁。其中恶性病变65例，良性病变13例。经EBUS-TBNA诊断75例，其中原发性肺癌61例，转移性肺癌1例，肺炎7例，肺结核5例，肺纤维化1例，70例获得了特异的病理学诊断依据，5例仅诊断为良性而未获得特异的病理学诊断依据，3例为假阴性。EBUS-TBNA对肺内良恶性病变鉴别的敏感度、特异度、阳性预测值、阴性预测值及诊断准确性分别为95％、100％、100％、81％、96％。8例来源或类型不明的恶性肿瘤中，结合免疫组织化学检测，确断5例原发性肺癌和1例转移性肺腺癌。1例高凝状态患者术中因穿刺部位的出血形成的阻塞中央气道引起血氧饱和度急剧降低，其余患者未见明显并发症。结论EBUS—TBNA是一项微创、安全的检查方法，对气管、支气管周围的肺内良恶性病变有着较高的诊断价值，结合免疫组织化学检查结果有助于明确恶性病变的病理来源和类型。

关键词：肺肿瘤免疫组织化学活组织检查针吸

国产经胸壁穿刺诊疗定位系统辅助肺结节穿刺活检的随机对照研究

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上海交通大学学报（医学版） 2020年第9期40卷 1218-1221页

作者：滕家俊聂蔚高志强徐建林孙加源钟华上海市胸科医院上海交通大学附属胸科医院呼吸与危重症医学科上海200030

目的·评估国产经胸壁穿刺诊疗定位系统辅助肺结节穿刺活检的应用价值。方法·采用前瞻性随机对照研究,纳入需进行肺结节穿刺活检明确病理诊断的113例患者,按照随机数字表法分组:辅助穿刺组(n=57)采用经胸壁穿刺诊疗定位系统,常规操作组... 详细信息

目的·评估国产经胸壁穿刺诊疗定位系统辅助肺结节穿刺活检的应用价值。方法·采用前瞻性随机对照研究,纳入需进行肺结节穿刺活检明确病理诊断的113例患者,按照随机数字表法分组:辅助穿刺组(n=57)采用经胸壁穿刺诊疗定位系统,常规操作组(n=56)采用传统的CT引导下肺穿刺活检。2组操作过程均由低年资医师在高年资医师的监督指导下完成。主要观察和比较2组穿刺耗时、CT扫描次数以及术后并发症。结果·辅助穿刺组操作耗时与常规操作组比较,差异无统计学意义[(26.7±8.0)min vs(25.0±7.8)min,P=0.261)];2组穿刺过程中CT扫描次数比较,差异无统计学意义(4.9±2.7 vs 5.1±2.7,P=0.810);2组术后气胸(15.8%vs 19.6%,P=0.592)和出血(17.5%vs 14.3%,P=0.636)的发生率比较,差异均无统计学意义。结论·经初步研究,国产经胸壁穿刺诊疗定位系统可以安全、有效地辅助临床医师完成肺穿刺活检。

关键词：肺结节穿刺活检电磁导航

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian jia William Yi Wang jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

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一类函数极值问题解法的说明

高师理科学刊 2008年第2期28卷 36-37页

作者：滕兴虎滕加俊周华任吴红解放军理工大学理学院江苏南京211101

讨论多元函数的极值或最值问题,常用的方法是利用多元函数极值的充分条件或拉格朗日乘数法,但运算过程往往比较复杂.对其中的某些问题,如果巧妙地利用目标函数或约束条件的几何性质,则解题思路简捷,而且运算简便,是一种求解多元函数的... 详细信息

讨论多元函数的极值或最值问题,常用的方法是利用多元函数极值的充分条件或拉格朗日乘数法,但运算过程往往比较复杂.对其中的某些问题,如果巧妙地利用目标函数或约束条件的几何性质,则解题思路简捷,而且运算简便,是一种求解多元函数的极值或最值问题的有效方法.但在应用这种方法时,往往是凭经验或直觉,而忽略这种方法的理论根据.通过3个定理给出了这种方法的合理性的说明,并且给出了这种方法的应用.

关键词：多元函数极值几何解法

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关于2个幂级数和的收敛半径的说明

高师理科学刊 2008年第3期28卷 86-87页

作者：滕兴虎滕加俊周华任吴红解放军理工大学理学院江苏南京211101

在众多教材中,仅仅指出了2个幂级数的和在某区间内收敛,而没有对这2个幂级数的和的收敛区间加以说明,因此关于2个幂级数的和的收敛半径往往会产生想当然的结论.为此,文中指出了2个幂级数的和的收敛半径的可能性,并举例予以说明.

关键词：幂级数幂级数和收敛半径