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基于特性数据的燃气涡轮发动机修正方法

航空发动机 2024年第3期50卷 114-121页

作者：王佳雯黄向华嵇润民中国航发动力控制系统研究所江苏无锡214063 南京航空航天大学能源与动力学院南京210016

针对燃气涡轮发动机部件特性不匹配造成的模型计算参数与实际试车参数之间的误差问题,提出一种基于特性数据的燃气涡轮发动机部件特性修正方法。通过变缩放参考中心依次对设计点、慢车点进行整体修正,实现特性图在整个工况范围内的大致... 详细信息

针对燃气涡轮发动机部件特性不匹配造成的模型计算参数与实际试车参数之间的误差问题,提出一种基于特性数据的燃气涡轮发动机部件特性修正方法。通过变缩放参考中心依次对设计点、慢车点进行整体修正,实现特性图在整个工况范围内的大致覆盖。通过局部修正非设计点所在的由相邻等转速线和β线所确定矩形域的特性数据,并采用插值法和拟合椭圆曲线法对等转速线的其他数据点进行补充修正,得到与试车数据匹配的特性图。以涡扇发动机为研究对象进行仿真验证,结果表明:所提出的特性修正方法能准确、快速地对发动机部件特性进行修正,与试车数据相比,修正后的模型各稳态点误差精度均在1.5%以内,满足工程精度需求,可用于发动机控制系统研究。

关键词：部件级模型特性修正非设计点匹配燃气涡轮发动机

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大鼠心肌成纤维细胞通过增加基质金属蛋白酶2活性抑制心肌细胞缝隙连接功能

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中国病理生理杂志 2024年第3期40卷 465-472页

作者：柏雪高鸿黄祥严旭胡廷菊陈锐安丽宋雨婷贵州医科大学麻醉学院贵州贵阳550002 中山大学附属第一医院贵州医院贵州贵阳550025 贵州医科大学附属医院麻醉科贵州贵阳550002

目的:探讨缺氧复氧(hypoxia/reoxygenation,H/R)后大鼠心肌成纤维细胞(cardiac fibroblasts,CFs)条件培养液对心肌细胞中缝隙连接蛋白43(connexin 43,Cx43)表达和缝隙连接功能的影响及其分子机制。方法:(1)将H9c2细胞随机分为5组:对照(c... 详细信息

目的:探讨缺氧复氧(hypoxia/reoxygenation,H/R)后大鼠心肌成纤维细胞(cardiac fibroblasts,CFs)条件培养液对心肌细胞中缝隙连接蛋白43(connexin 43,Cx43)表达和缝隙连接功能的影响及其分子机制。方法:(1)将H9c2细胞随机分为5组:对照(control)组、常氧(normal)组、基质金属蛋白酶2抑制剂ARP-100(ARP)组、H/R组和H/R+ARP组。荧光划痕技术评价缝隙连接功能,Western blot实验检测Cx43的表达及磷酸化水平,明胶酶谱法测定条件培养液中基质金属蛋白酶的活性。(2)将SD大鼠随机分为control组、ARP组、缺血再灌注(I/R)组和I/R+ARP组,每组8只。微电极阵列技术采集心律失常发生类型和持续时间,免疫组织化学实验检测心肌组织中Cx43蛋白的表达及分布,Western blot实验检测Cx43的表达及磷酸化水平。结果:与control组相比,H/R组Cx43蛋白表达显著下降(P<0.01),磷酸化水平下调(P<0.01),荧光扩散范围变窄(P<0.01),MMP2活性增加(P<0.01);ARP-100可降低大鼠I/R模型中心律失常评分(P<0.01)。结论:H/R处理的大鼠CFs条件培养液可影响大鼠心肌细胞中Cx43的表达、磷酸化水平及缝隙连接功能,其机制可能与H/R诱导的条件培养液中MMP2活性增加有关,抑制MMP2活性可减少大鼠离体全心I/R模型中心律失常评分。

关键词：缺氧复氧缺血再灌注心肌细胞缝隙连接蛋白43 基质金属蛋白酶

Trajectory Planning Algorithm Based on Quaternion for 6-DOF Aircraft Wing Automatic Position and Pose Adjustment Method

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Chinese Journal of Aeronautics 2010年第6期23卷 707-714页

作者： ZhuYongguo huang xiang Fang Wei Li Shuanggao Department of Mechanical and Electrical Engineering Nanjing University of A eronautics and Astronautics Nanjing 210016 China Aeronautical Manufacturing Technology Institute Shanghai Aircraft Manufacturing Co. Ltd. Shanghai 200436 China

A 6-degree of freedom （6-DOF） aircraft wing position and pose automatic adjustment method is presented to improve ARJ21 wing-fuselage connection precision and efficiency. Wing position and pose are adjusted by three pillars which are driven by six high-precision servo motors. During the adjustment process, wing is tracked and positioned by laser tracker. Wing initial position and pose are calibrated by using the measurement coordinates of assembly reference points. Wing target position and pose are calculated according to wing initial, fuselage position and pose, and relative position and pose requirements between wing and fuselage for the connection. Combining Newton-Euler method with quaternion position and pose analyzing method, the inverse kinematics of servo motors, together with the adjustment system dynamics is obtained. Wing quintic polynomial trajectory planning algorithm based on quatemion is proposed; the initial, target position and pose need to be solved and the intermediate moving path is uncertain. Simulation results show that the adjustment method has good dynamic characteristics and satisfies engineering requirements. Preliminary engineering application indicates that ARJ21 wing adjustment efficiency and precision are improved by using the proposed method.

关键词： aircraft assembly calibration position and pose adjustment trajectory planning quaternion

Enumeration of Cubic Cayley Graphs on Dihedral Groups

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Acta Mathematica Sinica,English Series 2017年第7期33卷 996-1010页

作者： Xue Yi huang Qiong xiang huang Lu LU College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830046P.R.China

Let p be an odd prime, and D2p = （a,b I aP = b2 = l,bab= a 1） the dihedral group of order 2p. In this paper, we completely classify the cubic Cayley graphs on D2p up to isomorphism by means of spectral method. By the way, we show that two cubic Cayley graphs on D2p are isomorphic if and only if they are cospectral. Moreover, we obtain the number of isomorphic classes of cubic Cayley graphs on D2 by using Gauss＇ celebrated law of quadratic reciprocity.

关键词： Cayley graph dihedral group cospectral isomorphic classes quadratic reciprocity

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中国地表水环境微塑料赋存特征及驱动因素

中国环境科学 2024年第8期44卷 4599-4609页

作者：陈钦威王鹏丁明军张华聂明华黄高翔江西师范大学地理与环境学院鄱阳湖湿地与流域研究教育部重点实验室江西南昌330022

为阐明中国地表水环境微塑料(MPs)的赋存特征及驱动因素,基于已发表文献,收集了1944个采样点的MPs特征,分析地理环境和实验方法对MPs特征的影响.研究表明:中国地表水环境中MPs的丰度范围为水体0~204183items/m^(3),平均值为5465.26items... 详细信息

为阐明中国地表水环境微塑料(MPs)的赋存特征及驱动因素,基于已发表文献,收集了1944个采样点的MPs特征,分析地理环境和实验方法对MPs特征的影响.研究表明:中国地表水环境中MPs的丰度范围为水体0~204183items/m^(3),平均值为5465.26items/m^(3),沉积物0~79931items/kg,平均值为1374.51items/kg.中国地表水环境中MPs丰度呈现显著的空间异质性;水体中,内陆河流域MPs平均丰度最高(13185.77items/m^(3)),东南诸河流域(2678.07items/m^(3))的平均丰度最低.沉积物中,淮河流域的MPs平均丰度(2145.61items/kg)最高,而海河流域(294.82items/kg)最低.水体和沉积物中MPs的形态主要以纤维状(58.29%/47.21%)､碎块状(23.20%/30.03%)为主.粒径以小型MPs(<0.5mm)(59.61%/62.76%)为主.颜色以透明(30.18%/28.17%)为主.微塑料材质主要为聚乙烯(PE)(25.49%/27.78%)､聚丙烯(PP)(25.36%/22.69%)等.水体微塑料特征主要受自然环境因素影响,丰度、形状和颜色特征均与自然环境因子(气温,降水)显著相关.沉积物MPs特征主要受社会经济因素影响,丰度、形状和粒径特征与社会经济环境因子(GDP､夜光强度､人口密度)显著相关.不同实验处理下的MPs特征,包括丰度、形态、颜色和聚合物类型均有显著差异;偏最小二乘路径分析显示,实验处理过程对MPs特征的影响与地理环境相当;缺乏标准化的实验方法使得不同实验结果难以比较和验证,因此,迫切需要制定标准化的实验过程,减少实验处理对MPs观测特征的影响.

关键词：地表水环境微塑料特征赋存特征驱动因素地理环境实验过程

The Stochastic Maximum Principle for a Jump-Diffusion Mean-Field Model Involving Impulse Controls and Applications in Finance

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Journal of Systems Science & Complexity 2020年第1期33卷 26-42页

作者： LI Cailing LIU Zaiming WU Jinbiao huang xiang School of Mathematics and Statistics Central South UniversityChangsha 410083China Research and Development Center Agricultural Bank of ChinaBeijing 100161China

This paper establishes a stochastic maximum principle for a stochastic control of mean-field model which is governed by a Lévy process involving continuous and impulse *** authors also show the existence and uniqueness of the solution to a jump-diffusion mean-field stochastic differential equation involving impulse *** for its application,a mean-variance portfolio selection problem has been solved.

关键词： Impulse control jump-diffusion Markowitz’s mean-variance model stochastic maximum principle

A Classification of Spectrum-determined Circulant Digraphs

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 703-709页

作者： Zheng-xin QIN Ji-xiang MENG Qiong-xiang huang School of Mathematics and Information Technology Jiangsu Second Normal University Nanjing 210013 China Department of Mathematics Xinjiang University Urumuqi 830054 China

Some researchers have proved that Adam＇s conjecture is wrong. However, under special conditions,it is right. Let Zn be a cyclic group of order n and Cn（S） be the circulant digraph of Zn with respect to S？Zn／{0}. In the literature, some people have used a spectral method to solve the isomorphism for the circulants of prime-power order. In this paper, we also use the spectral method to characterize the circulants of order paqbωc（where p,q and ω are all distinct primes）, and to make Adam＇s conjecture right.

关键词： Circulant digraph Isomorphism Spectrum Cyclotomic polynomial

Research status and development trends of evaporative cooling air-conditioning technology in data centers

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Energy and Built Environment 2023年第1期4卷 86-110页

作者： Junjie Chu xiang huang Institute of Building Environment and Energy China Academy of Building ResearchBeijing 100013China School of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China

This paper systematically describes the technical principles,evaluation indicators,system forms and research progress of air-side evaporative cooling air conditioning systems,water-side evaporative cooling air conditioning systems and freon-side evaporative cold coagulation heat air conditioning systems of Data *** order to reduce the energy consumption of the refrigeration and air-conditioning system in the Data center,the applica-tion conditions and scenarios of the different forms of evaporative cooling air-conditioning systems should be considered ***,it is very important that the renewable energy-dry air can be used to the greatest *** efforts would contribute to China’s 2030"Carbon Peak"and 2060"Carbon Neutral."

关键词： Data center Evaporative cooling Air-side Water-side Freon-side

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等规聚丙烯拉伸取向片晶结构的温度关联性

高分子通报 2024年第3期37卷 358-367页

作者：林浩严飞国江黄想姜胜宝许梦伊中国电力科学研究院武汉430074

为了探究加工温度对热拉伸聚丙烯取向晶体结构的影响规律,将等规聚丙烯(iPP)铸片在不同温度下拉伸到相同应变,并通过二维广角/小角X射线散射、差示扫描量热仪、动态力学分析等手段,对拉伸取向iPP的微观结构特性进行了系统研究。结果表明... 详细信息

为了探究加工温度对热拉伸聚丙烯取向晶体结构的影响规律,将等规聚丙烯(iPP)铸片在不同温度下拉伸到相同应变,并通过二维广角/小角X射线散射、差示扫描量热仪、动态力学分析等手段,对拉伸取向iPP的微观结构特性进行了系统研究。结果表明:经过热拉伸后,由球晶形貌演变成纤维晶形貌,纤维晶体由高度取向片晶和无定形层交替堆叠排列构成;升高温度引起结晶性能增强,结晶度和片晶平均厚度随温度连续递增;提高温度造成结晶相与无定形相之间的物性差异变大,两相链段运动松弛温度的变化趋势相反;热拉伸过程中新形成了不同厚度(熔点)的片晶,高熔点片晶是通过熔融-再结晶机理形成,而低熔点片晶由应变诱导结晶方式获得。本研究初步阐明了拉伸温度对聚丙烯取向片晶结构的影响规律和作用机制,对于开展结晶聚合物拉伸加工过程中多层次结构调控与性能优化具有参考价值。

关键词：等规聚丙烯拉伸温度片晶结晶度熔点