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基于高空飞机激光通信的轨迹预报、跟踪和指向系统

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光学学报 2024年第6期44卷 229-237页

作者：焦崇淼贺岩胡善江侯春鹤陈勇强陈卫标中国科学院上海光学精密机械研究所空间激光传输与探测技术重点实验室上海201800 中国科学院大学材料与光电研究中心北京100049 国科大杭州高等研究院浙江杭州310024

针对水下平台与高空飞机的激光通信中有效通信时间短、使用信标光的捕获对准时间较长、链路不易建立的问题,设计了一套基于水下平台的高空飞机轨迹预报跟踪及指向系统。系统根据飞机发送的航行参数对飞机轨道进行预报,并驱动伺服电机进... 详细信息

针对水下平台与高空飞机的激光通信中有效通信时间短、使用信标光的捕获对准时间较长、链路不易建立的问题,设计了一套基于水下平台的高空飞机轨迹预报跟踪及指向系统。系统根据飞机发送的航行参数对飞机轨道进行预报,并驱动伺服电机进行跟踪指向。仿真分析了轨道预报算法的误差,并将轨道预报算法应用在实际实验中。实验结果表明,水下平台接收到航行参数后,能在2 s内建立上行通信链路。该算法能够在0.6 s内预测60 s内的轨道位置,误差小于350 m,对应的理论指向误差不超过0.51 mrad。通过比较指向电机的实时反馈与理论指向角,得到系统的指向误差为0.77 mrad。所设计的系统在满足通信指向精度的同时缩短了链路的建立时间,为水下平台与高空激光系统的猝发激光通信提供了具有高可靠性的保障。

关键词：激光通信跟踪指向系统指向精度轨迹预报

我国普惠性民办幼儿园组织氛围发展的差异分析——基于对辽宁省沈阳市326名教师的调查

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成都师范学院学报 2024年第4期40卷 73-83页

作者：贺敬雯胡芸菲王春贺沈阳师范大学学前与初等教育学院辽宁沈阳110034

为探究我国普惠性民办幼儿园的组织氛围,以辽宁省沈阳市10所普惠性民办幼儿园的326名教师为调查对象,对普惠性民办幼儿园组织氛围实施问卷调查,同时从中随机抽取10名教师和2名园长进行深度访谈。结果表明:普惠性民办幼儿园组织氛围整体... 详细信息

为探究我国普惠性民办幼儿园的组织氛围,以辽宁省沈阳市10所普惠性民办幼儿园的326名教师为调查对象,对普惠性民办幼儿园组织氛围实施问卷调查,同时从中随机抽取10名教师和2名园长进行深度访谈。结果表明:普惠性民办幼儿园组织氛围整体处于中下水平,且维度不均衡;当前普惠性民办幼儿园组织氛围的主要类型是封闭型和开放型;在普惠性民办幼儿园组织氛围感知上,教师敬业行为维度得分最高,园长限制行为和园长监督行为维度得分最低;不同教龄与不同岗位教师感知组织氛围存在极其显著性差异,在学历变量上存在显著性差异。基于前述结果,从幼儿园园长、幼儿园教师和幼儿家长三个层面提出了提高普惠性民办幼儿园组织氛围水平的相关建议。

关键词：普惠性民办幼儿园组织氛围幼儿园教师学前教育教师专业发展

基于Hsp70基因的绵羊肺炎支原体TaqMan检测方法的建立及其遗传演化分析

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畜牧兽医学报 2024年第4期55卷 1684-1695页

作者：江锦秀张靖鹏林裕胜刘维巍胡奇林万春和福建省农业科学院畜牧兽医研究所福州350013 福建农林大学动物科学学院(蜂学学院) 福州350002

热休克蛋白70 (heat shock protein 70,Hsp70)是绵羊肺炎支原体(Mycoplasma ovipneumoniae, Movi)的重要膜蛋白,是机体内高度保守的生物分子,但在种间差异大,可作为分子生物学检测的候选靶区。为建立基于Hsp70基因的Movi通用型TaqMan实... 详细信息

热休克蛋白70 (heat shock protein 70,Hsp70)是绵羊肺炎支原体(Mycoplasma ovipneumoniae, Movi)的重要膜蛋白,是机体内高度保守的生物分子,但在种间差异大,可作为分子生物学检测的候选靶区。为建立基于Hsp70基因的Movi通用型TaqMan实时荧光定量PCR(qPCR)检测方法,并进一步了解其遗传变异情况,本研究基于GenBank中Movi的Hsp70基因特征,设计特异性的引物及探针,建立了基于Hsp70基因的绵羊肺炎支原体qPCR检测方法。应用建立的检测方法对88份山羊鼻拭子样品及43份疑似羊支原体性肺炎(Mycoplasmal pneumonia of sheep and goats, MPSG)病料进行检测。将检测结果为Movi阳性的肺组织样品进行分离鉴定,并对分离株Hsp70基因进行序列分析。结果显示,建立的qPCR检测方法其相关系数为1.00,扩增效率为96.0%,斜率为-3.411,Y轴截距为37.29。特异性强,与丝状支原体山羊亚种(Mycoplasma mycoides subsp.capri, Mmc)、山羊支原体山羊肺炎亚种(Mycoplasma capricolum subsp.capripneumoniae, Mccp)、莱氏无胆甾原体(Acholeplasmalaidlawii, AL)、无乳支原体(Mycoplasma agalactiae, Maga)、伪结核棒状杆菌(Corynebacterium pseudotuberculosis, CP)、羊口疮病毒(orf virus, ORFV)、牛支原体(Mycoplasma bovis, Mb)等牛羊常见病原均无交叉反应;敏感性高,最低检测限为5.72 copies·μL^(-1);重复性优,组内变异系数和组间变异系数均小于1.00%。6株Movi分离株Hsp70基因全长均为1 818 bp,与其它Movi参考株核苷酸和氨基酸同源性分别为96.0%~99.4%和98.0%~100.0%;进一步分析发现,山羊源Movi均比绵羊源多1个N-糖基化位点。遗传演化分析表明,其均处于ClusterⅠA亚分支(均为山羊源)。综上,本研究建立了特异性强、敏感性高、重复性优的基于Hsp70基因的Movi的qPCR检测方法。序列分析发现,不同来源Movi的Hsp70基因核苷酸同源性高;遗传演化分析证实,Movi福建株与山羊源分离株遗传关系较近。本研究不仅为Movi临床诊断提供了技术支持,更为进一步了解Movi遗传演化规律提供参考。

关键词：绵羊肺炎支原体 Hsp70基因 TaqMan实时荧光定量PCR方法序列分析

Wide Band Gap Non-Fullerene Small Molecular Acceptors Containing Spirobifluorene and Benzotriazole with Three Different End-Capped Groups for P3HT-Based Organic Solar Cells

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Chinese Journal of Chemistry 2018年第5期36卷 392-398页

作者： Xiaoyu Wen Bo Xiao Ailing Tang Junyi hu chunhe Yang Erjun Zhou Department of Chemistry School of Science Beijing Jiaotong University Beijing 100044 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China University of Chinese Academy of Sciences Beijing 200049 China

Spirofluorene （SF） and benzo[d][1,2,3]triazole （BTA） have been considered as promising building blocks to construct n-type photovoltaic materials. Herein, three new small molecule acceptors （SMAs） named BTA21, BTA23 and BTA27 with the structure of A2=A1-D-AI^A2 have been designed, in which SF and BTA were used as a central unit of D and bridged acceptor unit of A1, respectively. In addition, 3-ethylrhodanine, 2-（3-ethyl-4-oxothiazolidin-2-ylidene）malononitrile and malononitrile were chosen as terminal acceptor units to modulate the properties of the final SMAs. Three SMAs show wide optical band gaps （Eg） of 2.19, 2.15 and 2.22 eV, respectively, with gradually down-shift of the lowest unoccupied molecular orbital {LUMO） levels in the order of BTAZl, BTA23 and BTA27 depending on the electron-withdrawing capability of terminal acceptor units. BTA21 shows great advantages with respect to donor poly（3-hexylthiophene）（P3HT） over BTA23 and BTA27, such as well energy-level matching, complementary absorption and proper morpholgy, Concequently, P3HT：BTA21 shows the best power conversion efficiency （PCE） value of 3.28% with an open-circuit voltage （Voc） of 1.02 V, a short-circuit current （Jsc） of 5.45 mA.cm-2 and a fill factor （FF） of 0.59. These results indicate that the terminal acceptor group end-capped in SMAs plays a significant role in controlling their optical, electronic, and photovoltaic properties.

关键词： benzotriazole organic photovoltaic P3HT small molecular acceptor wide band gap

Modeling and Global Conflict Analysis of Firewall Policy

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China Communications 2014年第5期11卷 124-135页

作者： LIANG Xiaoyan XIA chunhe JIAO Jian hu Junshun LI Xiaojian Beij ing Key Laboratory of Network Technology Beihang University Beijing 100191 R R. China Beijing Information Science & Technology University Beijing 100192 P. R. China Software Development Center of China Agricultural Bank Beijing 100073 P. R. China College of Computer Science and Information Technology Guangxi Normal University Guilin 541004 Guangxi Province P. R. China

The global view of firewall policy conflict is important for administrators to optimize the policy.It has been lack of appropriate firewall policy global conflict analysis,existing methods focus on local conflict detection.We research the global conflict detection algorithm in this paper.We presented a semantic model that captures more complete classifications of the policy using knowledge concept in rough set.Based on this model,we presented the global conflict formal model,and represent it with OBDD(Ordered Binary Decision Diagram).Then we developed GFPCDA(Global Firewall Policy Conflict Detection Algorithm) algorithm to detect global conflict.In experiment,we evaluated the usability of our semantic model by eliminating the false positives and false negatives caused by incomplete policy semantic model,of a classical algorithm.We compared this algorithm with GFPCDA algorithm.The results show that GFPCDA detects conflicts more precisely and independently,and has better performance.

关键词：防火墙冲突分析建模冲突检测语义模型策略冲突测算法形式化模型

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分布式多经验池的无人机自主避碰方法

信息与控制 2023年第4期52卷 432-443页

作者：徐佳胡春鹤北京林业大学工学院北京100083

为满足多无人机(multi-UAVs)的协同任务中高效自主避碰的需求,在基于数据驱动的强化学习方法的基础上,提出了一种分布式多经验池深度确定性策略梯度避碰方法(DMEP-DDPG),使单个无人机在多机环境下仅依靠自身传感数据即可自主避碰作业。... 详细信息

为满足多无人机(multi-UAVs)的协同任务中高效自主避碰的需求,在基于数据驱动的强化学习方法的基础上,提出了一种分布式多经验池深度确定性策略梯度避碰方法(DMEP-DDPG),使单个无人机在多机环境下仅依靠自身传感数据即可自主避碰作业。首先,针对强化学习任务在长周期下的稀疏回报问题,设计了基于引导型奖励函数系统回报机制;其次,为克服单一经验池样本效率低带来的策略收敛困难的问题,构建了新型的分布式多经验池更新的确定性策略梯度框架;最后,在多种多无人机协同任务环境中测试了DMEP-DDPG方法的避碰性能,并与其它基于学习的避碰策略进行了性能指标对比,结果验证了DMEPDDPG方法的可行性和有效性。

关键词：强化学习深度确定性策略梯度(DDPG) 多无人机避碰自主感知

Semantics-Based Compliance An a lys is o f N e two rk S e cu rity Policy Hie ra rch ie s

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China Communications 2012年第7期9卷 22-35页

作者： Yao Shan Xia chunhe hu Junshun Jiao Jian Li Xiaojian Beijing Key Laboratory of Network Technology Beihang University Beijing 100191 P. R. China Beijing Information Technology University Beijing 100192 P. R. China College of Computer Science and Information Technology Guangxi Normal University Guilin 541004 P. R. China

Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language (OWL) to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given higher level security policy and the lower level ones to evaluate the compliance for the policy refinement approach. The method is verified in the case study. The experimental results demonstrate that the proposed method evaluates the semantic similarity between policy and implementation accurately, and that the algorithm of concept similarity analysis reflects the subjective similarity judgment of policy and implementation more accurate than the other algorithms.

关键词：语义本体Web语言 Lys 立方网络安全策略层次结构安全服务网络环境

构建社会主义和谐社会必须坚持科学执政——兼论中国共产党执政具体规律

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理论前沿 2007年第3期492卷 16-18页

作者：胡纯和中共安徽省委党校

构建社会主义和谐社会必须坚持科学执政。只有科学执政才能坚定构建和谐社会的方向,提供科学的世界观、有力的制度保障和正确的方法论。科学执政是中国共产党执政的具体规律。

关键词：科学执政和谐社会执政规律

Scalable and Identifier/Locator-Splitting Routing Protocol for Mobile Ad Hoc Networks

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China Communications 2012年第1期9卷 102-110页

作者： Wang Haiquan Chen Meng hu Junshun Xia chunhe Beijing Key Laboratory of Network Technology Beihang University Beijing 100191 P. R. China School of Computer Science and Engineering Beihang University Beijing 100191 P. R. China State Key Laboratory of Virtual Reality Technology and System Beihang University Beijing 100191 P. R. China School of So ware Beihang University Beijing 100191 P. R. China

In the traditional Internet Protocol (IP) architecture, there is an overload of IP semantic problems. Existing solutions focused mainly on the infrastructure for the fixed network, and there is a lack of support for Mobile Ad Hoc Networks (MANETs). To improve scalability. a routing protocol for MANETs is presented based on a locator named Tree-structure Locator Distance Vector (TLDV). The hard core of this routing method is the identifier/locator split by the Distributed Hash Table (DHT) method, which provides a scalable routing service. The node locator indicates its relative location in the network and should be updated whenever topology changes. Locator space is organized as a tree-structure, and the basic routing operation of the TLDV protocol is presented. TLDV protocol is compared to some classical routing protocols for MANETs on the NS2 platform. Results show that TLDV has better scalability.

关键词：网络基础设施路由协议可扩展性移动Ad 定位器无线自组网分裂识别