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Petrography,geochemistry and provenance of the sediments of the Early Cretaceous Yanguoxia Formation,Lanzhou-Minhe Basin,Northwest China

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Journal of Mountain Science 2018年第9期15卷 2068-2088页

作者： DU Ding-ding MUGHAL Muhammad Saleem zhang cheng-jun School of Earth Sciences and Mineral Resources Lanzhou UniversityLanzhou 730000China Key Laboratory of Western China's Mineral Resources of Gansu Province Lanzhou 730000China Institute of Geology University of Azad Jammu and KashmirMuzaffarabad 13100Pakistan

Lanzhou-Minhe Basin is situated on the middle Qilian orogenic belt. Yanguoxia Formation contains abundance of maroon siltstones, mudstones and red sandstones of the lake facies. These sedimentary rocks recorded the process of the tectonic uplift of Qilian Mountains during the Early Cretaceous. We discovered plentiful dinosaur footprints, worm burrows, bird footprints, worm tracks-trails, ripple marks and cross lamination in the Yanguoxia site. Integrated petrographic studies classified sandstones of Yanguoxia Formation as feldspathic litharenite. All plots in the QFL(Q or Qt, total quartz; F, feldspar; L, lithic grains) and Qm FLt(Qm, monocrystalline quartz; Lt, lithic grains plus polycrystalline quartz) diagrams fall in the recycled orogen provenance field and quartzose recycled field, respectively, implying the source occurred the tectonic activity. Furthermore, geochemical study indicates that the Yanguoxia standstone was formed in an unstable continental setting due to the northwards movement of Indian Plate triggered the collision between the Qilian fold belt and the Qinlingfold belt. These sediments were derived from a mixed source and then deposited in the Lanzhou-Minhe Basin. Most of the felsic components were derived from the granitoid rocks of the Qilian Mountains due to the rapid and intense uplift during the Early Cretaceous while the mafic components were contributed by the basic and ultrabasic rocks of the rapidly rising ophiolite in the Qilian Mountain area. Bivariant log-log plot of Qp/(F+L)(Qp, polycrystalline quartz) against Q/(F+L) shows that Yanguoxia Formation was deposited in the semihumid and semi-arid. Moreover, the pollen also exhibits that the environmental condition during the deposition of Yanguoxia Formation was warm and wet, which affirm such environment was benefit to dinosaur survival. Geochemical study also infers that the Yanguoxia Formation was deposited under the oxidizing condition in a shallow marine environment. The minerals id

关键词： Lanzhou-Minhe Basin YanguoxiaFormation Petrography Geochemistry Provenanceand weathering Teetonism and environment

Deflagration and detonation induced by shock wave focusing at different Mach numbers

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Chinese Journal of Aeronautics 2024年第2期37卷 249-258页

作者： Zezhong YANG jun cheng Bo zhang School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Shock wave focusing is an effective way to create a hot spot or a high-pressure and hightemperature region at a certain place,showing its unique usage in detonation initiation,which is beneficial for the development of detonation-based *** flame propagation behavior after the autoignition induced by shock wave focusing is crucial to the formation and self-sustaining of the detonation *** this study,wedge reflectors with two different angles(60°and 90°)and a planar reflector are employed,and the Mach number of incident shock waves ranging from 2.0 to 2.8 is utilized to trigger different flame propagation *** pressure transducers and the high-speed schlieren imaging system are both employed to investigate the shock-shock collision and ignition *** results reveal a total of four flame propagation modes:deflagration,DDT(Deflagration-to-Detonation Transition),unsteady detonation,and direct *** detonation wave formed in the DDT and unsteady detonation mode is only approximately 75%-85%of the Chapman-Jouguet(C-J)speed;meanwhile,the directly induced detonation wave speed is close to the C-J *** waves,which are strong evidence for the existence of detonation waves,are discovered in *** usage of wedge reflectors significantly reduces the initial pressure difference ratio needed for direct detonation *** also provide a practical method for differentiating between detonation and deflagration modes,which involves contrasting the speed of the reflected shock wave with the speed of the theoretically nonreactive reflected shock *** findings should serve as a reference for the detonation initiation technique in advanced detonation propulsion engines.

关键词： Deflagration Detonation Hydrogen Ignition Shock wave focusing

考虑平行系统特征的双活调度系统的设计与应用

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科学技术与工程 2024年第13期24卷 5450-5456页

作者：王佳刘璇赵崇曹仁威吴海勇张峻诚广东电网有限责任公司广州供电局广州510620 东方电子股份有限公司烟台264000

为提高电网运行的稳定性,需要构建稳定可靠的电网调度系统,现提出一种考虑平行系统特征的双活调度系统。通过构建主备两个数据中心,根据应用业务量在主备调间进行调整,实现对资源的充分利用。发生故障时,另一个正常运行的中心将承担所... 详细信息

为提高电网运行的稳定性,需要构建稳定可靠的电网调度系统,现提出一种考虑平行系统特征的双活调度系统。通过构建主备两个数据中心,根据应用业务量在主备调间进行调整,实现对资源的充分利用。发生故障时,另一个正常运行的中心将承担所有业务。并将平行系统视为电网虚拟运行系统,将真实与虚拟系统结合后得到电网双活调度系统,并具有管理和控制模块、实验和评估模块、学习和培训模块等功能。该系统通过对数据进行初始化处理,计算出电力分配结果,建立双层任务调度模型,利用遗传算法求解模型,从而实现双活调度系统的优化调度。对系统进行试验测试,试验结果表明:设计系统所提方法达到最优分配值所需时间短、效率高、电网信息调度总量大,调度能力强,调度信息的安全性高。说明所设计的双活调度系统具有可行性,利于区域电网的优化调度。

关键词：平行系统双活调度系统电力调度虚拟系统遗传算法

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复杂网络中节点度增量的预测研究

信息技术 2024年第5期48卷 30-37页

作者：余文斌钱铭杨泽俊沈鑫禹李琪张成军南京信息工程大学江苏大气环境和装备技术协同创新中心南京210044 南京信息工程大学计算机学院南京210044 南京信息工程大学数字取证教育部工程研究中心南京210044

节点的度属性是复杂网络的拓扑性质,因此对节点度增量的预测在复杂网络的未来趋势预测中具有重要意义。文中设计了基于链路预测相似性算法的节点度增量预测方法,并分析复杂网络中节点度增量的预测准确性。通过对比连边和度增量的预测结... 详细信息

节点的度属性是复杂网络的拓扑性质,因此对节点度增量的预测在复杂网络的未来趋势预测中具有重要意义。文中设计了基于链路预测相似性算法的节点度增量预测方法,并分析复杂网络中节点度增量的预测准确性。通过对比连边和度增量的预测结果,表明两者之间不存在相关性。进一步实验,文中分析了节点自身度属性和未来度增量之间的关系,实验表明:大度节点的度增量预测准确性较高,小度节点的准确性较低。由此可知,大度节点之间的差异性使得未来度增量的预测结果更加准确,同时表明链路预测结果存在异质性。

关键词：复杂网络链路预测度增量度属性异质性

A Novel Disturbance Observer Based Fixed-Time Sliding Mode Control for Robotic Manipulators With Global Fast Convergence

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan zhang Jiabin Hu jun cheng Zheng-Guang Wu Huaicheng Yan IEEE Zhejiang University of Technology Guangxi Normal University Zhejiang University the East China University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

基于MobileNet-CBAM模型的轻量级鸟类识别方法

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信息技术 2024年第8期48卷 1-7,17页

作者：成迪雷毅张成军陈亚当刘文杰余文斌南京信息工程大学江苏大气环境和装备技术协同创新中心南京210044 南京信息工程大学计算机学院南京210044 南京信息工程大学数字取证教育部工程研究中心南京210044

对于鸟类识别任务,当前一些深度学习网络模型的效果并不理想,针对现有模型的痛点,提出了一种在识别精度、计算性能、资源消耗和实用性上更具优势的轻量级鸟类识别方法。该方法基于轻量级MobileNet模型,融合了卷积注意力机制(Convolution... 详细信息

对于鸟类识别任务,当前一些深度学习网络模型的效果并不理想,针对现有模型的痛点,提出了一种在识别精度、计算性能、资源消耗和实用性上更具优势的轻量级鸟类识别方法。该方法基于轻量级MobileNet模型,融合了卷积注意力机制(Convolutional Block Attention Module,CBAM),在减少模型复杂度的同时增强了局部特征的提取能力,与主流模型的对比实验验证了该模型的有效性。此外,该模型能够应用于机器人、便携式手机等硬件平台,扩展了应用场景,并添加数据库来进行辅助计算,减少额外开销,兼具便携性和实用性。

关键词： MobileNet 注意力机制 Android平台鸟类识别图像识别

Detrital apatite fission track constraints on Cenozoic tectonic evolution of the northeastern Qinghai-Tibet Plateau, China： Evidence from Cenozoic strata in Lulehe section, Northern Qaidam Basin

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Journal of Mountain Science 2018年第3期15卷 532-547页

作者： DU Ding-ding zhang cheng-jun MUGHAL Muhammad Saleem WANG Xiao-yu BLAISE Dembele GAO jun-ping MA Yuan LUO Xin-rong School of Earth Sciences and Mineral Resources Lanzhou University Lanzhou 730000 China Key Laboratory of Western China's Mineral Resources of Gansu Prouince Lanzhou 730000 China Institute of Geology University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

The Northern Qaidam Basin is located at the northeastern part of the Qinghai-Tibetan Plateau. It contains very thick Cenozoic terrestrial clastic sediments, which records the formation of the northern Qaidam Basin due to compressional deformation during the Indo-Asian collision. In this paper, we used detrital apatite fission-track thermochronology, including 4 sandstones and 2 conglomerates samples from the Lulehe section, to reveal the Cenozoic evolution of the northern Qaidam Basin. Fission-track dating indicated the source region of the Lulehe section has experiencedimportant cooling and uplifting in the Late Cretaceous(at ~85.1 Ma and ~65 Ma) and the Eocene(~52 Ma), respectively. The AFT age distribution on the section suggested that the provenance of Lulehe section sediments were mainly derived from the south Qilian Shan(Qilian Mountains) and Altun Shan(Altun Mountains), and two significantly provenance changes may occur at 43.4-46.1 Ma and ~37.8 Ma, respectively. The results may have strong constrains on the Cenozoic deformation and tectonic evolution of the northern Qaidam Basin and Qinghai-Tibet Plateau.

关键词： Northern Qaidam Basin Apatite Fission-Track Tectonic evolution Provenance analysis

Mapping of the heading date gene HdAey2280 in Aegilops tauschii

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Journal of Integrative Agriculture 2016年第12期15卷 2719-2725页

作者： LIU Guo-xiang zhang Li-chao XIA Chuan JIA Ji-zeng zhang jun-cheng zhang Qiang DONG Chun-hao KONG Xiu-ying LIU Xu Key Laboratory of Crop Germplasm Resources and Utilization Ministry of Agriculture/National Key Facility for Crop Gene Resources and Genetic ImprovementInstitute of Crop SciencesChinese Academy of Agricultural Sciences

An optimum heading date is essential for sustainable crop productivity and ensuring high yields. In the present study, F2：3 populations were generated by crossing an early-heading accession, Y2280, with a late-heading accession, Y2282. The heading dates of the F2 and F3 populations were investigated in a field study. Using publicly available simple sequence repeat （SSR） markers, the early heading date gene HdAey2280 was mapped onto Aegilops tauschfi chromosome 7DS between the flanking markers wmc438 and barc126 at distances of 15 and 9.1 cM, respectively. Further analysis indicated that HdAey2280 is a novel heading date gene. New SSR markers were developed based on the Ae. tauschfi draft genome sequence, resulting in four new markers that were linked to the heading date gene HdAey2280. The closest distance of these markers was 1.9 cM away from the gene. The results collected in this study will serve as a framework for map-based cloning and marker-assisted selection in wheat breeding programs in the future.

关键词： Aegilops tauschii heading date molecular markers HdAey2280

Platypnea-orthodeoxia syndrome in a patient with a pre-existing patent foramen ovale successfully treated with an atrial septal occluder

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Journal of Geriatric Cardiology 2015年第3期12卷 323-325页

作者： Ting-Ting zhang Ge-Sheng cheng jun WANG Xing-Ye WANG Xue-Gang XIE Ya-Juan DU Yu-Shun zhang The Second Department of Cardiology First Hospital Affiliated to Xi'an Jiaotong University Xi 'an Shaarzri Province China

Platypnea orthodeoxia syndrome is associated with dyspnea and arterial oxygen desamration accentuated by an upright posture. It can be secondary to an intracardiac shunt. We report a case of platypnea-orthodeoxia syndrome （POS） in a 58-year old male patient who had a pre-existing patent foramen ovale （PFO） and substantial pulmonary pathologies. He was successfully treated by percutaneous transcatheter closure of the PFO. Our case highlights the importance of recognition of this rare syndrome in patients who present with unexplained hy- poxia for whom transcatheter closure of the interatrial shunt can be safely carded out.

关键词： Intracardiac shunt Platypnea-orthodeoxia syndrome Patent foramen ovale Transcatheter closure