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Initial virtual flight test for a dynamically similar aircraft model with control augmentation system

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Chinese Journal of Aeronautics 2017年第2期30卷 602-610页

作者： Guo Linliang zhu minghong Nie Bowen Kong Peng Zhong Chengwen School of Aeronautics Northwestern Polytechnical University Low Speed Aerodynamics Institute China Aerodynamics Research and Development Center

To satisfy the validation requirements of flight control law for advanced aircraft,a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel.A 3-degree-offreedom gimbal,ventrally installed in the model,was used in conjunction with an actively controlled dynamically similar model of aircraft,which was equipped with the inertial measurement unit,attitude and heading reference system,embedded computer and *** model,which could be rotated around its center of gravity freely by the aerodynamic moments,together with the flow field,operator and real time control system made up the closed-loop testing *** model is statically unstable in longitudinal direction,and it can fly stably in wind tunnel with the function of control augmentation of the flight control *** experimental results indicate that the model responds well to the operator＇s *** response of the model in the tests shows reasonable agreement with the simulation *** difference of response of angle of attack is less than 0.5°.The effect of stability augmentation and attitude control law was validated in the test,meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.

关键词： 3-degree-of-freedom gimbal Dynamic test Flight dynamics simulation Flight control system Real time Wind tunnel

Numerical Investigation of the Effects of Wind Tunnel Model Vibrations on the Measured Aerodynamic Properties of Airfoils and Wings

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航空工程进展 2010年第4期1卷 317-326页

作者： Zhengyin Ye,minghong zhu,Zhengke Zhang(National Key Laboratory of Science and Technology on Aerodynamic Design and Research,Northwestern Polytechnical University,Xi’an 710072,China) National Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical University Xi'an 710072 China

This paper presents a numerical prediction of the unsteady flow field around oscillating airfoils at high angles of attack by solving unsteady Reynolds-averaged Navier-Stokes equations with SST turbulence model in order to simulate the effects of wind tunnel model vibrations on the aerodynamic properties of airfoils,especially high-aspect-ratio wings in a wind *** effects of the phase lagging between different modes of oscillations,i.e.,the airfoil plunging oscillation mode,the pitching oscillation mode,and the forward-backward oscillation mode,are also *** is shown that the vibrations (oscillations) of airfoils can cause the unsteady shedding of large-size separated vortex to precede the stationary stall incidence,hence lead to a stall onset at some earlier (lower) incidence than that in the steady *** different phase lagging has different effect on the flow *** the pitching oscillation mode has small phase lagging behind the plunging oscillation mode,the effect of vibrations is ***,if the amplitude of the oscillations is large enough,and the different modes of vibrations match or combine appropriately,the unsteady stall may occur 2° earlier in angle of attack than the case where airfoils keep stationary.

关键词： model vibration airfoil wind tunnel

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全国首座跨海高速铁路5G网络规划建设工程

数字通信世界 2024年第9期 129-132页

作者：朱铭鸿中国移动通信集团福建有限公司泉州分公司福建泉州362000

福厦客专5G网络无线主设备项目在规划建设中面临首座高铁跨海大桥覆盖、首次大型下沉站台覆盖、高速动车通信配套可靠性等技术挑战,通过创新设备安装规范、下沉大层站台设备安装和450km/h高速列车需求的偏置式漏缆固定方案等解决方案,... 详细信息

福厦客专5G网络无线主设备项目在规划建设中面临首座高铁跨海大桥覆盖、首次大型下沉站台覆盖、高速动车通信配套可靠性等技术挑战,通过创新设备安装规范、下沉大层站台设备安装和450km/h高速列车需求的偏置式漏缆固定方案等解决方案,成功克服了技术难题。项目的管理创新与数智化应用提升了施工效率和管理水平,确保了高质量的工程交付。福厦客专的5G网络开通显著提升了专项场景的用户网络使用感知,为未来高铁建设提供了宝贵经验。

关键词：福厦客专跨海大桥高铁技术数智化应用

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聚焦核心素养以创新小学数学课堂教学

当代教研论丛 2020年第5期7卷 54-55页

作者：朱明虹福建省仙游县实验小学福建莆田351200

核心素养时代下,核心素养是课堂教学改革的重要方向。小学数学教学要与教材内容、任务高度融合,积极创新课堂教学模式。教师应对学生在课堂中的主体地位予以尊重,在由浅入深的教学过程中锻炼学生的表达能力,培养学生对数学概念的敏感度... 详细信息

核心素养时代下,核心素养是课堂教学改革的重要方向。小学数学教学要与教材内容、任务高度融合,积极创新课堂教学模式。教师应对学生在课堂中的主体地位予以尊重,在由浅入深的教学过程中锻炼学生的表达能力,培养学生对数学概念的敏感度,在不断地探究、反思学习中量化思维,进而形成良好的数学核心素养。

关键词：小学数学核心素养创新教学

New insight into the origin and evolution of the flora and fauna of Hainan Island, China

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Science China Earth Sciences 2025年第1期68卷 52-61页

作者： Hua zhu Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to Southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the Leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the Late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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风洞虚拟飞行模型机与原型机动力学特性分析

航空学报 2016年第8期37卷 2583-2593页

作者：郭林亮祝明红孔鹏聂博文钟诚文西北工业大学航空学院西安710072 中国空气动力研究与发展中心绵阳621000

在低速风洞虚拟飞行试验系统中,采用三自由度(3-DOF)球铰支撑动力学相似缩比飞机模型,在气动力矩作用下试验模型可绕质心自由转动。这种带约束的运动与具有六自由度(6-DOF)的真实大气飞行存在差别,鉴于此,对各影响因素逐个剖离并进行了... 详细信息

在低速风洞虚拟飞行试验系统中,采用三自由度(3-DOF)球铰支撑动力学相似缩比飞机模型,在气动力矩作用下试验模型可绕质心自由转动。这种带约束的运动与具有六自由度(6-DOF)的真实大气飞行存在差别,鉴于此,对各影响因素逐个剖离并进行了数值模拟和对比分析。结果表明:位移约束使两者间的动力学特性产生较明显的差异,缩比的影响符合相似准则规律,机构摩擦、模型重心与支撑点不重合影响较小,常值干扰力矩对模型的初始响应有一定影响。对比分析结果可以用于指导风洞虚拟飞行试验的开展,并有助于完善风洞虚拟飞行试验技术及其拓展应用。

关键词：风洞虚拟飞行试验动力学特性飞行力学仿真动态试验三自由度球铰

Lianyungang——A Would-be International Trade Centre

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China's Foreign Trade 1996年第12期 32-32页

作者： zhu Zhenfa Zhou minghong

Lianyungang is one of China’s eight majorseaports, the East Bridge Tower of thenew Eurasia Continental Bridge. During theEighth Five-Year Plan period, opening tothe outside world and foreign-oriented econ-omy in Lianyungang City developed *** year, foreign trade, the utilization offoreign capital, foreign project contractingand labour service export increased by over50 percent each. Its superiority, which

关键词： will A Would-be International Trade Centre Lianyungang

风洞虚拟飞行试验中的飞行控制系统快速原型设计与部署技术

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空气动力学学报 2017年第5期35卷 700-707页

作者：刘志涛聂博文郭林亮祝明红西北工业大学航空学院陕西西安710072 中国空气动力研究与发展中心四川绵阳621000

利用风洞虚拟飞行技术可在风洞中开展飞行器的飞行控制验证与评估研究。飞行控制子系统是虚拟飞行试验技术的核心,采用控制系统快速原型技术,可实现嵌入式实时飞行控制代码自动生成和快速部署,从而大幅降低飞行控制系统集成难度,有效提... 详细信息

利用风洞虚拟飞行技术可在风洞中开展飞行器的飞行控制验证与评估研究。飞行控制子系统是虚拟飞行试验技术的核心,采用控制系统快速原型技术,可实现嵌入式实时飞行控制代码自动生成和快速部署,从而大幅降低飞行控制系统集成难度,有效提高风洞虚拟飞行试验效率。本文概述了Φ3.2m风洞虚拟飞行试验系统组成和现状,详细介绍了基于该系统的飞行控制系统快速原型开发平台和部署方法,通过某飞机缩比模型全数字仿真、半实物仿真和风洞虚拟飞行试验,验证了该技术具有良好的通用性和开放性等特点,可以满足不同型号飞行器风洞虚拟飞行试验飞行控制系统集成需求。

关键词：虚拟飞行飞行控制系统快速控制原型全数字仿真半实物仿真风洞试验

MR弥散峰度成像平均弥散率鉴别肝脏良、恶性病变:Meta分析

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中国介入影像与治疗学 2021年第11期18卷 677-682页

作者：张舒强胡潇刘一帆朱明洪重庆市涪陵中心医院放射科重庆涪陵408000

目的采用Meta分析方法评估MR弥散峰度成像(DKI)平均弥散率(MD)鉴别肝脏良、恶性病变的效能。方法于Pubmed、Cochrane Library、Embase、中国知网、维普和万方医学网中检索自建库至2021年3月20日以DKI参数MD值鉴别诊断肝脏良、恶性病变... 详细信息

目的采用Meta分析方法评估MR弥散峰度成像(DKI)平均弥散率(MD)鉴别肝脏良、恶性病变的效能。方法于Pubmed、Cochrane Library、Embase、中国知网、维普和万方医学网中检索自建库至2021年3月20日以DKI参数MD值鉴别诊断肝脏良、恶性病变的相关文献;根据标准筛选文献,提取相关资料,以Stata 15.1和Meta-Disc 1.4软件分析MD值鉴别肝脏良、恶性病变的效能。结果共纳入6篇文献,含493例患者、225个良性及362个恶性共587个病灶。汇总分析结果显示,肝脏恶性病变的MD值小于良性[标准均数差(SMD)=-1.31,95%CI(-1.54,-1.09),Z=11.34,P<0.0001];以MD值鉴别肝脏良、恶性病变的合并敏感度、特异度、阳性似然比、阴性似然比及诊断比值比分别为0.78[95%CI(0.74,0.82)]、0.73[95%CI(0.67,0.79)]、2.74[95%CI(2.22,3.39)]、0.31[95%CI(0.25,0.38)]及9.71[95%CI(6.63,14.21)];汇总受试者工作特征曲线的曲线下面积(AUC)为0.8238。以MD值判断肝脏恶性病变为恶性的验后概率为76%,判断良性病变为恶性的验后概率为22%。结论DKI的MD值鉴别肝脏良、恶性病变的效能较高。

关键词：肝肿瘤磁共振成像,弥散弥散峰度成像荟萃分析