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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence Technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning Liu wenjiang zhao Yao Wang Kai Shen Zhong Su Wenhao Qi Yuedong Xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

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Research on the navigation method of large-scale differential tailcontrol improvised guided munitions based on rotational speed constraints

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Defence technology 2024年第8期 155页

作者： Ning Liu wenjiang zhao Yao Wang Kai Shen Zhong Su Wenhao Qi Yuedong Xie

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Experimental and numerical study of combustion characteristics of ammonia-hydrogen-air swirling flame with/without secondary air injection

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Chinese Journal of Aeronautics 2024年第4期37卷 243-255页

作者： Chunyu LIU Chenhu GAO Yue HUANG Hua JIN Dan zhao wenjiang XU Yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361005China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand

Ammonia (NH_(3)) is currently considered to be a potential carbon-free alternative fuel,and its large-scale use as such would certainly decrease greenhouse gas emissions and meet increasingly stringent emission *** the low flame propagation speed and high NO production of NH_(3) hinder its direct application as a renewable fuel,co-combustion of NH_(3)–H_(2)is an effective way to overcome these *** this study,the combustion characteristics of NH_(3)–H_(2)swirling flames under different equivalence ratios and H_2blending ratios conditions are both numerically and experimentally ***,the One-Dimensional (1D) laminar flame computation presents a comparison base and the Three-Dimensional (3D) numerical simulation yields detailed flame property ***,the high-speed camera takes instantaneous swirl flame images and the gas analyzer measures the NO emission at the exit plane of the flame *** and quantitative analysis is performed on the flame structure and NO emission for a series of NH_(3)–H_(2)swirl *** variation trends of the NO emission calculated using different techniques agree very *** quantitative results show that the NO emissions are much higher at lean equivalence ratios than those at rich equivalence ratios,and such difference is closely related to the combustion flame ***,it is shown that the utilization of secondary air injection can achieve a significant reduction in NO emissions at the exit of the combustion chamber at equivalence ratios less than or equal to 0.9.

关键词： Ammonia combustion Swirling flow NO emission characteristics Secondary combustion Chemical reaction mechanism

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The Red Edge Parameters Diversification Disciplinarian and Their Application in Winter Wheat

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计算机工程 2002年第S1期28卷 154-159页

作者： HUANG wenjiang, WANG Jihua, zhao Chunjiang, WANG Zhijie (Beijing Agriculture Information Technology Research Center, Beijing 100089, China wenjianghuang @ ***)λλ Beijing Agriculture Information Technology Research Center Beijing 100089 China wenjianghuang ***

Some red edge parameters(red, Min600-720λ, dredλ, dminλλ, dred / dmin∑λ, d680-750λ, andnir) and the relationship between these parameters and the parameters of biochemistry and biophysics of winter wheat were studied by regression analysis. The results indicated that there existed some changes in these red edge parameters in the whole growth stages, and there were strong correlations between red edge parameters and parameters of biochemistry and biophysics. Thus, the red λedge parameters were found valuable for assessment of wheat parameters of biochemistry and biophysics. Thered can be used to λestimate the soluble sugar content and the chlorophyll content. The dred was the best estimator of total nitrogen content. LAI can λbe estimated by Min600-720 satisfactorily.

关键词： Red edge Winter wheat Biochemistry

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Remote sensing of quality traits in cereal and arable production systems:A review

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The Crop Journal 2024年第1期12卷 45-57页

作者： Zhenhai Li Chengzhi Fan Yu zhao Xiuliang Jin Raffaele Casa wenjiang Huang Xiaoyu Song Gerald Blasch Guijun Yang James Taylor Zhenhong Li College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590ShandongChina Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs Information Technology Research CenterBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of Agriculture and Rural AffairsBeijing 100081China DAFNE Universitàdella TusciaVia San Camillo de Lellis01100 ViterboItaly Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China International Maize and Wheat Improvement Center(CIMMYT) PO Box 5689Addis AbabaEthiopia ITAP Univ.MontpellierINRAEInstitut AgroMontpellier 34000France College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054ShaanxiChina

Cereal is an essential source of calories and protein for the global *** predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy *** use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality *** studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing *** this paper,the key quality traits that are of interest to producers and consumers are *** literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality *** review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.

关键词： Remote sensing Quality traits Grain protein Cereal

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Betulinic acid protects against ovarian impairment by decreasing F-2 toxin-induced oxidative stress and inflammation associated with the downregulation of p38 expression in mice

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Food Science and Human Wellness 2024年第3期13卷 1292-1302页

作者： Li Kong Xinyu Gao Lijuan Zhu Xing Lin You Huang Chunlin Huang wenjiang Yang Yazhi Chen Haoqiang zhao Jing Wu Zhihang Yuan Jin’e Yi Hunan Engineering Research Center of Livestock and Poultry Health Care College of Veterinary MedicineHunan Agricultural UniversityChangsha 410128China

F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in *** acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological *** this study,the antioxidative and anti-inflammatory effects of BA and its underlying mechanism are explored in F-2 toxin-triggered mouse ovarian *** found that BA alleviated the F-2 toxin-induced ovarian impairment by stimulating follicle growth,reducing inflammatory cell infiltration,repairing damaged mitochondria and endoplasmic ***,BA not only reversed F-2 toxin-induced reduction of follicle stimulating hormone(FSH)and luteinizing hormone(LH)levels in the serum,but also restrained the protein expression of the estrogen receptors a(ERa)and ERβ.Moreover,BA restored the balance of F-2 toxin-induced ovarian redox system ***,we found that 0.25 mg/kg BA played an anti-inflammatory role in the F-2 toxin-induced ovarian impairment by decreasing interleukin-1β(IL-1β).IL-6,and tumor necrosis factor-α(TNF-α)mRNA expression,as well as inhibiting p38 protein *** data demonstrated that BA exerts its protective effect on F-2 toxin-induced ovarian oxidative impairment and inflammation by inhibiting p38 expression,which implies a natural product-based medicine to ameliorate F-2 toxin-caused female reproductive toxicity and provides a detoxifying method for food contaminated by mycotoxin.

关键词： Betulinic acid F-2 toxin Ovarian damage p38 MAPK signaling pathway

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Research on Development Process of 7 Speed Wet Dual Clutch Transmission

Research on Development Process of 7 Speed Wet Dual Clutch T...

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FISITA 2012 World Automotive Congress--Volume 5:Advanced Transmission System and Driveline

作者： Yong Chen Mike Turner Michael Gilcrist wenjiang zhao Daguo Luo Fuquan zhao Zhejiang Geely Automobile Research Institute CO. LTD

Seven speed wet dual clutch automatic transmission is a product characterized by an integration of electrics,mechanics and *** optimized efficiency,good NVH performance and durability low cost are considered during the *** order to save time and optimize design,process development research method based on simulation model is ***,basic test is combined to guarantee validity of simulation ***,design process is optimized.

关键词： Dual clutch transmission(DCT) Dual clutch DCTF NVH analysis Basic test

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电影技术实践的人类学解读:群体本能、思维架构与进化方式

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电影评介 2023年第6期 57-60页

作者：赵文江山西传媒学院动画与数字艺术学院

电影学总是以电影的技术与文本内部的思维惯性来阐释电影,没有意识到人类是被习惯性活动所组织的产物。在某种意义上,人类的生活与文化都是被“无剧本的电影”组织起来的。人类出于生物性的惯性认知与行动,对自己的行为方式缺乏真正了... 详细信息

电影学总是以电影的技术与文本内部的思维惯性来阐释电影,没有意识到人类是被习惯性活动所组织的产物。在某种意义上,人类的生活与文化都是被“无剧本的电影”组织起来的。人类出于生物性的惯性认知与行动,对自己的行为方式缺乏真正了解。在此意义上,电影既可以成为人类学视野中人类文明的产物,又可以被视为一种回观人类的技术实践。电影毋庸置疑是一种组织活动,既是由人类组织和进行的文化活动,同时也是回观和塑造人类的文化活动——尽管其历史距今只有百余年之久,但却在诞生后的百余年中深刻地影响了人类认识与实践的方方面面。

关键词：思维惯性人类学视野文本内部人类学解读生物性电影学人类文明认识与实践

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自行火炮发射动力学研究

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北京理工大学学报 1999年第2期19卷 147-151页

作者：毕世华赵文江北京理工大学机电控制工程系

目的研究自行火炮发射动力学分析方法并将分析计算结果同有关的靶场实验结果进行对比说明其可行性．方法采用Ｋａｎｅ－Ｈｕｓｔｏｎ方法建立连续射击冲击激励作用下自行火炮的多刚体动力学模型，提出了约束矩阵和简化矩阵的概念，以便... 详细信息

目的研究自行火炮发射动力学分析方法并将分析计算结果同有关的靶场实验结果进行对比说明其可行性．方法采用Ｋａｎｅ－Ｈｕｓｔｏｎ方法建立连续射击冲击激励作用下自行火炮的多刚体动力学模型，提出了约束矩阵和简化矩阵的概念，以便于自动完成约束处理和系统动力学方程的约减，并编制了相应的计算机软件．结果分析计算结果和有关的靶场实验数据吻合较好，总结了系统响应的特点以及计算结果存在误差的原因．结论本文所述分析方法正确。

关键词：自行火炮发射动力学多体系统动力学火炮

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基于地磁信息的高速自旋飞行体转速测量法

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传感技术学报 2022年第7期35卷 913-918页

作者：赵文江刘宁苏中戚文昊北京信息科技大学高动态导航技术北京市重点实验室北京100192 北京信息科技大学现代测控技术教育部重点实验室北京100192

针对目前制导炮弹这类高速自旋飞行体转速变化范围大,且难以实现全程转速有效测量的问题,提出了一种基于地磁时域标量归一信息的转速实时在线测量方法:首先,研究高速自旋条件下的飞行体地磁运动特征,根据初始时间窗内接收的数据确定初... 详细信息

针对目前制导炮弹这类高速自旋飞行体转速变化范围大,且难以实现全程转速有效测量的问题,提出了一种基于地磁时域标量归一信息的转速实时在线测量方法:首先,研究高速自旋条件下的飞行体地磁运动特征,根据初始时间窗内接收的数据确定初始归一幅值,并计算初始转速;其次,通过前一时刻得出的转速计算下一个时间窗长度,在时间窗内对接收到的数据进行动态归一处理;最后,判断地磁零点时刻,根据所得零点计算转速,并计算下一个时间窗长度,以此类推,最终实现实时运动转速计算。仿真与试验结果表明,计算得出的转速值与实际设定值相差不超过8.2%,实现了对高速自旋飞行体全程转速的有效测量。

关键词：高速自旋飞行体地磁信息转速测量地磁标量

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