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双模无人机总体设计研究

兵器装备工程学报 2018年第1期39卷 92-96页

作者：梁毅辰屈高敏雷鑫鑫西安航空学院飞行器学院陕西西安710077 西安京东天鸿科技有限公司陕西西安710077

提出了一种复合升力布局,将固定翼和多旋翼布局的优势相结合,提出了作业系统的基本构成,对比了无人机不同的发射和回收方式,提出了无人机总体方案和控制系统总体方案,根据总体方案对无人机进行总体设计,提出了初始设计目标和总体性能参... 详细信息

提出了一种复合升力布局,将固定翼和多旋翼布局的优势相结合,提出了作业系统的基本构成,对比了无人机不同的发射和回收方式,提出了无人机总体方案和控制系统总体方案,根据总体方案对无人机进行总体设计,提出了初始设计目标和总体性能参数,对无人机进行了气动布局设计,提出了动力系统的总体方案,并验证了该种飞行器的合理性。

关键词：无人机总体设计复合升力布局垂直起降性能计算

基于误差矢量的选择映射序列降低OFDM信号峰均比方法

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中国科技论文 2016年第8期11卷 909-912页

作者：侯俊张上鑫雷欣欣惠飞长安大学信息学院西安710071

正交频分复用系统的高峰值会导致发送端对功率放大器的线性度要求极高,从而会降低功率放大器的效率。提出了一种基于误差矢量度量来衡量传输信号峰值平均功率比的选择映射序列算法。在考虑高功率放大器作用的条件下,通过限制选择映射序... 详细信息

正交频分复用系统的高峰值会导致发送端对功率放大器的线性度要求极高,从而会降低功率放大器的效率。提出了一种基于误差矢量度量来衡量传输信号峰值平均功率比的选择映射序列算法。在考虑高功率放大器作用的条件下,通过限制选择映射序列的扰码个数,从中选取与原始序列误差矢量幅度最小的加扰信号进行传输。仿真结果表明,所提出的方法与同类方法相比,有更好的峰值降低效果和更低的复杂度。

关键词：通信技术峰值平均功率比选择映射序列正交频分复用系统

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黏土矿物对页岩储集空间及吸附能力的影响

特种油气藏 2017年第3期24卷 1-8页

作者：高凤琳宋岩姜振学张欣欣陈磊油气资源与探测国家重点实验室北京102249 中国石油大学(北京) 北京102249 中国石油勘探开发研究院北京10083 中国科学院地质与地球物理研究所北京100029

在地层条件下,受多种因素综合作用,黏土矿物对页岩储层特征及吸附能力的作用较为复杂,难以进行客观评价。基于此,结合大量文献调研,通过前人XRD分析、扫描电镜观察、N_2吸附实验、甲烷等温吸附实验等方法,研究黏土矿物特征及其影响因素... 详细信息

在地层条件下,受多种因素综合作用,黏土矿物对页岩储层特征及吸附能力的作用较为复杂,难以进行客观评价。基于此,结合大量文献调研,通过前人XRD分析、扫描电镜观察、N_2吸附实验、甲烷等温吸附实验等方法,研究黏土矿物特征及其影响因素,以期更客观地评价黏土矿物对页岩储层及吸附能力的贡献。研究认为:黏土矿物具有较大的比表面积,但受多种因素影响,其对甲烷分子的吸附能力主要取决于黏土矿物与有机质的赋存关系;黏土矿物对有机质既有富集作用又有催化生烃作用,富集的有机质可减少黏土矿物表面的吸附位,而有机质生烃产生的有机质孔隙又增加了吸附空间,二者的相互作用及相对含量的匹配关系对页岩储层含气量影响较大;广泛存在的地层水虽然能降低其对甲烷分子的吸附能力,但并不意味着页岩储层含气量一定会低,这主要取决于有机质的发育情况。正确认识黏土矿物的作用可为最优含气量组合分析以及勘探"甜点"选择提供依据。

关键词：角度不整合薄油环网格转换水平网格动态网格加密数值模拟

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师范院校大学生学习倦怠的比较研究

中国健康心理学杂志 2011年第4期19卷 465-467页

作者：张媛雷欣欣白银霞中国.内蒙古医学院公共卫生管理学院呼和浩特010059 内蒙古电子信息职业技术学院内蒙古第三医院

目的探讨不同师范院校大学生学习倦怠的情况。方法抽取全国5所师范类院校883名大学生,用《大学生学习倦怠问卷》调查。结果①师范类大学生存在学习倦怠现象。其中,行为不当得分最高,其次为成就感低和情绪低落;②不同性别师范类大学生在... 详细信息

目的探讨不同师范院校大学生学习倦怠的情况。方法抽取全国5所师范类院校883名大学生,用《大学生学习倦怠问卷》调查。结果①师范类大学生存在学习倦怠现象。其中,行为不当得分最高,其次为成就感低和情绪低落;②不同性别师范类大学生在行为不当(t=2.588,P≤0.05)和成就感低维度(t=-2.414,P≤0.05)有显著差异;③不同年级大学生在倦怠总分(F=5.852,P≤0.01)、情绪低落(F=8.706,P≤0.001)和成就感低维度(F=13.508,P≤0.001)有显著差异,在行为不当维度不存在显著差异;④不同生源地的师范类大学生在行为不当维度(F=3.768,P≤0.05)、成就感低维度(F=7.438,P≤0.05)和倦怠总分(F=5.247,P≤0.05)有显著差异;⑤不同学校学生在倦怠总分(t=5.101,P≤0.001)、情绪低落(t=-4.478,P≤0.001)和成就感低维度(t=-3.177,P≤0.01),行为不当维度(t=-4.728,P≤0.001)有显著差异。结论师范类大学生存在不同程度的学习倦怠,需从社会、学校、个人等方面予以重视。

关键词：大学生学习倦怠比较研究

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课程发展的社会学思考

新疆教育学院学报 2009年第1期25卷 43-46页

作者：雷欣欣陈伟唐琳娜新疆师范大学教育科学学院新疆乌鲁木齐830054 新疆生产建设兵团一中新疆乌鲁木齐830000

文章从三个角度展开分析:课程的社会性分析、教育社会学三大流派对课程的透析和现代课程的发展。通过回溯课程与社会学相结合并从中汲取养分促进自身发展的历程,考量课程的发展脉络,为课程发展的时代性提供思索的途径。

关键词：课程的社会性教育社会学流派课程观

Long-Chain Alkenones in the South Yellow Sea Sediments and Their Indicative Significance for Haptophytes Species

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Journal of Ocean University of China 2024年第5期23卷 1287-1296页

作者： XU Yakun YANG xinxin XIAO Rui XING lei Key Laboratory of Marine Chemistry Theory and Engineering Technology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory of Marine Ecology and Environment Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Long-chain alkenones(LCAs)have been widely used as important biomarkers in palaeoceanographic ***,the commonly used LCAs proxies are mainly based on C_(37) alkenones,and it is still lack of the studies about the distribution and in-dications of LCAs with different chain lengths other than C_(37) ***,the composition and distribution of LCAs were ana-lyzed in surface sediments from the southern Yellow Sea(SYS)and a sedimentary core(A02-C)from the central Yellow Sea(YS)mud *** results showed that C_(37),C_(38) and C_(39) alkenones were the major LCAs in surface sediments of the SYS,and the relative contents of C_(38:2)Et,C_(37:2)Me,C_(37:3)Me,C_(38:2)Me,C_(38:3)Et,C_(38:3)Me,C_(39:2)Et and C_(39:3)Et were 18.3%-59.8%,22.6%-41.2%,7.4%-23.0%,6.6%-15.4%,3.8%-13.3%,3.6%-8.7%,2.8%-6.0% and 0.7%-3.0%,*** the relationships of U_(38Me)^(K)-U_(38Et)^(K) and U_(37)^(K')-U_(38Et)^(K) indicate that LCAs are mainly derived from Emiliania huxleyi(***).High ratios of total C_(37) alkenones to total C_(38) alkenones(K_(37)/K_(38))(1-1.2)were found in the central SYS,corresponding to the relatively high abundance of ***;while low ratios of K_(37)/K_(38)(0.7-0.9)were observed at nearshore area of the SYS where Gephyrocapsa oceanica(***)has rela-tively high *** spatial distribution of K_(37)/K_(38) ratio is also consistent with that of coccolithophores nannofossil in the *** addition,K_(37)/K_(38) ratio in core A02-C varied from 0.7 to 1.1 with a gradual decreasing trend during the past 5.5 *** suggests that the relative abundance of *** decreased gradually,caused by the changes in the Yellow Sea Warm Current(YSWC)and the East Asian Winter Monsoon(EAWM)during this period.

关键词： alkenones southern Yellow Sea sediment Yellow Sea Warm Current

H2 solubility and mass transfer in anthraquinone working solution： Experimental and modeling study

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Chinese Journal of Chemical Engineering 2017年第2期25卷 143-148页

作者： Zhigang lei Yaru Guo Yanyan Guo xinxin Li Chengna Dai State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

This work was focused on the measurement of the solubility of hydrogen （H2） in anthraquinone working solution at temperatures of 30.0-80.0℃ and pressures of 0.2-3.0 MPa by the method of experimental and COSMO-RS model study. The influence of various factors, i.e., including pressure, temperature and solvent volume ratio, on H2 solubility was investigated. According to the experimental results, H2 solubility in anthraquinone working solution increases with the increase of pressure. At low pressures, the temperature had little effect on H2 solubility while under high pressures H2 solubility increases with increasing temperature. Henry＇s constant In/-/has a good linear relationship with 1/T （lnH = -- 1319.1/T ＋ 9.91 ）. The effect of volume ratio of trioctyl phos- phate to trimethylbenzene on the solubility of hydrogen was studied and the results showed that increasing the amount of trimethylbenzene was conducive to the dissolution of hydrogen. In addition, there is a linear relationship between ln（（Po - Pe） / （Pt - Pe）） and the time t. Gas-liquid mass transfer coefficient was obtained by calculating the slope of the line.

关键词： HydrogenSolubilityAnthraquinone working solutionTrimethylbenzeneCOSMO-RS modelMass transfer

An in situ nanoparticle recombinant strategy for the enhancement of photothermal therapy

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Chinese Chemical Letters 2022年第1期33卷 328-333页

作者： xinxin Liu Cuixia Zheng Yueyue Kong Hao Wang lei Wang Luoyang Central Hospital Affiliated to Zhengzhou University Luoyang 471009China School of Pharmaceutical Sciences Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Drug Preparation Technologies Ministry of EducationSchool of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Targeting Therapy and Diagnosis for Critical Diseases Zhengzhou UniversityZhengzhou 450001China Tumor Immunity and Biomaterials Advanced Medical Center Zhengzhou UniversityLuoyang 471009China

Photothermal therapy(PTT)-induced immune response has attracted much attention,however,which cannot work at full *** this study,the simvastatin(SV)adjuvant is loaded into gold nanocages(AuNCs)to develop a simple drug delivery system,which can efficiently utilize the tumor-associated antigens(TAAs)for improving immune ***/SV-mediated PTT treatment enhances tumor cells damage and promotes the release of TAAs which are immediately captured by Au NCs/SV to form AuNCs/SV/TAAs recombinant ***,AuNCs/SV/TAAs can accumulate in lymph nodes effectively due to the suitable size of~55 nm and hyperthermia-induced vasodilative *** the codelivery of antigen and adjuvant is beneficial to stimulating the maturation of dendritic cells for further activating T *** a word,the recombinant strategy could make full use of TAAs to produce an individual powerful immunotherapy.

关键词： Photothermal therapy Tumor-associated antigens Recombinant nanoparticle T cells activation Individual immunotherapy

An Overview of General Theory of Security

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China Communications 2017年第7期14卷 1-10页

作者： Min lei Yixian Yang xinxin Niu Yu Yang Jie Hao Information Security Center Beijing University of Posts and Telecommunications Guizhou University Guizhou Provincial Key Laboratory of Public Big Data Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science & Technology

Cyber security lacks comprehensive theoretical guidance. General security theory, as a set of basic security theory concepts, is intended to guide cyber security and all the other security work. The general theory of security aims to unify the main branches of cyber security and establish a unified basic theory. This paper proposal an overview on the general theory of security, which is devoted to constructing a comprehensive model of network security. The hierarchical structure of the meridian-collateral tree is described. Shannon information theory is employed to build a cyberspace security model. Some central concepts of security, i.e., the attack and defense, are discussed and several general theorems on security are presented.

关键词： cyber security network attack and defense meridian-collateral theory