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Provenance Study of Fe–Ti Oxide Minerals in the Quaternary Sediments in Yichang Area and Its Implication of Formation Time of the Yangtze Three Gorges, China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1598-1608页

作者： XIANG Fang DU Wen HUANG Henxu kang dongya ZHU Hongbo FENG Qin State Key Laboratory of Oil and Gas reservoir Geology and exploitation Chengdu University of Technology Shangdong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Mineral Shangdong University of Science and Technology Institute of sedimentary geology Chengdu University of Technology

The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debatable. Fe-Ti oxide minerals are seldom used to study sediment provenance, expecially using scanning electron microscopy （SEM）, and energy dispersive spectrometer （EDS）. In this study, the provenance of Quaternary sediments in Yichang area, which is located to the east of the Yangtze Three Gorges, was investigated by using SEM and EDS to research Fe-Ti oxides. The Panzhihua vanadium titanomagnetite and Emeishan basalt outcrop are located to the west of the Three Gorges. Further, the materials from them are observed in the Quaternary sediments of Yichang area. Fe-Ti oxide minerals from the Huangling granite are observed in the Yunchi and Shanxiyao Formations, which were formed before 0.75 Ma B.P., whereas Fe-Ti oxide minerals from the Huangling granite, Panzhihua vanadium titanomagnetite, and Emeishan basalt are observed in the riverbed and fifth-terrace sediments of the Yangtze River, which were formed after 0.73 Ma B.P.. Thus, we can infer that the Three Gorges formed after the deposition of the Shanxi Formation and before the fifth-terrace; i.e., 0.75-0.73 Ma B.P..

关键词： Yangtze Three Gorges Yichang area Quaternary sediments Fe-Ti oxide minerals China

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鄂尔多斯盆地上古生界砂岩岩石学特征及岩性差异

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断块油气田 2019年第3期26卷 299-303页

作者：康东雅向芳邹佐元张萌成都理工大学沉积地质研究院

文中利用岩石薄片、扫描电镜等方法,详细分析了鄂尔多斯盆地东南部宜川-富县地区上古生界砂岩岩石学特征及岩性差异。研究结果表明:宜川地区本溪组—石千峰组的岩石类型主要为石英砂岩、岩屑砂岩、岩屑长石砂岩;富县地区与宜川地区基本... 详细信息

文中利用岩石薄片、扫描电镜等方法,详细分析了鄂尔多斯盆地东南部宜川-富县地区上古生界砂岩岩石学特征及岩性差异。研究结果表明:宜川地区本溪组—石千峰组的岩石类型主要为石英砂岩、岩屑砂岩、岩屑长石砂岩;富县地区与宜川地区基本相同,本溪组—太原组的岩石类型主要为石英砂岩,从山西组开始长石体积分数明显增加,出现岩屑长石砂岩和长石岩屑砂岩。由于构造运动、沉积相演化和物源变化的影响,造成沉积环境和物源区发生变化,本溪组—太原组与山西组—石千峰组砂岩的长石体积分数、岩屑成分、分选性和磨圆度等都不相同,从而导致研究区在不同地区和层位存在岩性差异。

关键词：上古生界岩石学特征岩性差异宜川-富县地区鄂尔多斯盆地

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Unlocking the power of tandem repeat variations to fine-tune rice phenotypes

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Science Bulletin 2025年第3期70卷 297-298页

作者： kang Chong Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

The diversity of crop phenotypes is shaped by numerous genomic *** staple cereals like rice,lots of functional variants,including quantitative trait locus(QTLs),have been identified and used to improve various crop traits(yield,quality,architecture,etc.).To breed ideal crop cultivars for agricultural production,we need more and more precise modulation of phenotypes to obtain desirable *** the past decade,genome editing techniques have enabled us to precisely change crop genome sequences,and also functional variants[1],[2],[3].

关键词： cultivar cereal precise

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Failure rate analysis and maintenance plan optimization method for civil aircraft parts based on data fusion

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Chinese Journal of Aeronautics 2025年第1期38卷 306-324页

作者： kang CAO Yongjie ZHANG Jianfei FENG School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Shanghai 201210China

In the face of data scarcity in the optimization of maintenance strategies for civil aircraft,traditional failure data-driven methods are encountering challenges owing to the increasing reliability of aircraft *** study addresses this issue by presenting a novel combined data fusion algorithm,which serves to enhance the accuracy and reliability of failure rate analysis for a specific aircraft model by integrating historical failure data from similar models as supplementary *** a comprehensive analysis of two different maintenance projects,this study illustrates the application process of the *** upon the analysis results,this paper introduces the innovative equal integral value method as a replacement for the conventional equal interval method in the context of maintenance schedule *** Monte Carlo simulation example validates that the equivalent essential value method surpasses the traditional method by over 20%in terms of inspection efficiency *** discovery indicates that the equal critical value method not only upholds maintenance efficiency but also substantially decreases workload and maintenance *** findings of this study open up novel perspectives for airlines grappling with data scarcity,offer fresh strategies for the optimization of aviation maintenance practices,and chart a new course toward achieving more efficient and cost-effective maintenance schedule optimization through refined data analysis.

关键词： Small sample data Data fusion Failure rate Maintenance planning Aircraft parts

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Residential Energy Scheduling With Solar Energy Based on Dyna Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 403-413页

作者： kang Xiong Qinglai Wei Hongyang Li the Institute of Systems Engineering Macau University of Science and Technology IEEE the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of Automation Chinese Academy of Sciences the School of Artificial Intelligence University of Chinese Academy of Sciences

Learning-based methods have become mainstream for solving residential energy scheduling problems. In order to improve the learning efficiency of existing methods and increase the utilization of renewable energy, we propose the Dyna actiondependent heuristic dynamic programming(Dyna-ADHDP)method, which incorporates the ideas of learning and planning from the Dyna framework in action-dependent heuristic dynamic programming. This method defines a continuous action space for precise control of an energy storage system and allows online optimization of algorithm performance during the real-time operation of the residential energy model. Meanwhile, the target network is introduced during the training process to make the training smoother and more efficient. We conducted experimental comparisons with the benchmark method using simulated and real data to verify its applicability and performance. The results confirm the method's excellent performance and generalization capabilities, as well as its excellence in increasing renewable energy utilization and extending equipment life.

关键词： Adaptive dynamic programming (ADP) dynamic residential scenarios optimal residential energy management smart grid

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三峡及邻区第四纪沉积物地球化学特征及其对古气候的指示

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成都理工大学学报（自然科学版） 2019年第6期46卷 746-753页

作者：朱宏博向芳王金元黄恒旭康东雅张萌油气藏地质及开发工程国家重点实验室(成都理工大学) 成都610059 贵州煤田地质局贵州六盘水553000

讨论三峡和宜昌地区第四纪古气候的演化过程及青藏高原隆升对古气候演化的影响。以三峡及宜昌地区第四纪沉积物为主要研究对象,在沉积剖面研究的基础上,对低夷平面、阶地及冲积扇和湖相沉积物进行地球化学元素分析,依据地球化学元素的... 详细信息

讨论三峡和宜昌地区第四纪古气候的演化过程及青藏高原隆升对古气候演化的影响。以三峡及宜昌地区第四纪沉积物为主要研究对象,在沉积剖面研究的基础上,对低夷平面、阶地及冲积扇和湖相沉积物进行地球化学元素分析,依据地球化学元素的变化曲线及沉积特征,认为三峡及宜昌地区第四纪古气候的演化趋势相似,经历了早更新世晚期及中更新世暖湿气候到晚更新世干冷气候的转变。结合全球气候背景、青藏高原隆升过程对气候影响等方面的资料,认为150 ka B.P.之后青藏高原隆升至4 km时,青藏高原对三峡及宜昌地区的古气候产生了较大影响。

关键词：第四纪古气候元素分析三峡宜昌

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三峡及邻区第四纪沉积与地貌特征对古气候的指示

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成都理工大学学报（自然科学版） 2018年第4期45卷 459-467页

作者：黄恒旭向芳王金元朱宏博杜雯康东雅油气藏地质及开发工程国家重点实验室(成都理工大学) 成都610059 贵州煤田地质局贵州六盘水553000

分析长江三峡及其邻区第四纪气候特征及可能的影响因素。在前人研究基础上,通过对万州、奉节、巫山和宜昌等地第四纪地貌特征,以及保存在夷平面、阶地、扇三角洲和湖相沉积中沉积物特征的综合分析研究表明:(1)三峡在早更新世为温暖潮湿... 详细信息

分析长江三峡及其邻区第四纪气候特征及可能的影响因素。在前人研究基础上,通过对万州、奉节、巫山和宜昌等地第四纪地貌特征,以及保存在夷平面、阶地、扇三角洲和湖相沉积中沉积物特征的综合分析研究表明:(1)三峡在早更新世为温暖潮湿环境,在0.11Ma B.P.左右发生气候转变,之后直至全新世为干燥寒冷环境;宜昌地区第四纪气候变化趋势与三峡地区相同。(2)三峡在早更新世到0.3Ma B.P.以来,沉积记录主要显示为暖湿气候;在0.3Ma B.P.以前,三峡基本不具备发育第四纪冰川的条件。导致三峡及宜昌地区在0.11Ma B.P.左右发生明显的沉积物差异和气候变化的原因,与发生在0.15Ma B.P.的青藏高原共和运动具有密切的关系。

关键词：三峡宜昌第四纪沉积特征古气候

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多服务器间基于动态身份的身份认证和密钥共识方案

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软件工程 2016年第10期19卷 4-8页

作者：王牧亢保元景东亚天津工业大学计算机科学与软件学院天津300387

多数的身份认证方案是依赖于单个的认证服务器与用户之间的相互认证,如果一个用户想要使用不同的网络服务,就必须向每一个服务器进行注册。然而要使得用户记住不同的身份和口令是非常困难的。最近,Li et al.分析了Sood et al.提出的多... 详细信息

多数的身份认证方案是依赖于单个的认证服务器与用户之间的相互认证,如果一个用户想要使用不同的网络服务,就必须向每一个服务器进行注册。然而要使得用户记住不同的身份和口令是非常困难的。最近,Li et al.分析了Sood et al.提出的多服务器间基于动态身份的认证方案,指出了其中存在的问题并且提出了一个改进的方案。Li et al.声称他们的方案可以保证用户的匿名性,提供了相互认证和共享密钥,并且可以抵抗一些常见的攻击。然而,通过仔细分析之后,我们发现Li et al.的方案容易受到假冒攻击。因此,本文提出了一种高效安全的多服务器间基于动态身份的相互认证和密钥共识方案并给出了安全性分析。

关键词：身份认证密钥共识多服务器安全性

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Thermal effects on wear behavior of additively manufactured NiTi shape memory alloys

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Chinese Journal of Aeronautics 2025年第1期38卷 147-164页

作者： Xianghui HUANG Nan kang Pei WANG Mohamed EL MANSORI Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne 51006France Henan Key Laboratory of High-Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843USA

NiTi alloys fabricated by laser powder bed fusion(LPBF)additive manufacturing technology not only address the compositional instability resulting from complex processes but also solve the challenges of difficult machining of intricate aerospace ***,there are very few reports on the wear behavior of LPBF-NiTi *** the present work,the effects of microstructure and thermal treatment,including heat treatment and frictional heat,on the wear behavior of LPBF-NiTi alloy and 100Cr6 ball were analyzed through a series of tribological experiments with different sliding *** the average sliding speed increases(0.079–0.216 m/s),the wear rate of the as-built and heat-treated samples tends to decrease in the range of 2.69×10^(-3)–0.97×10^(-3)mm^(3)/*** the heat-treated LPBF-NiTi alloy is 46%harder than the as-built alloy is,the latter has a higher toughness(505 MJ/m^(3))and greater transformation strain of SIM(0.097).This leads to a coupling effect of heat treatment and sliding speed on the wear *** addition,the wear track morphologies under different sliding speeds are asymmetric due to the 24% greater acceleration at the far end from the motor and the 2.15 mm deviation between the maximum speed position and the geometric center of the *** wear modes of the as-built and heat-treated samples included adhesive,abrasive and delamination ***,the wear morphologies and dominant wear modes change with the frictionally caused heat release induced by the sliding speed.

关键词： Additive manufacturing Laser powder bed fusion NiTi alloys Wear resistance Sliding speed

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Privacy Distributed Constrained Optimization Over Time-Varying Unbalanced Networks and Its Application in Federated Learning

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 335-346页

作者： Mengli Wei Wenwu Yu Duxin Chen Mingyu kang Guang Cheng the School of Cyber Science and Engineering Southeast University IEEE the School of Mathematics Frontiers Science Center for Mobile Information Communication and Security Southeast University the Purple Mountain Laboratories the School of Mathematics Southeast University

This paper investigates a class of constrained distributed zeroth-order optimization(ZOO) problems over timevarying unbalanced graphs while ensuring privacy preservation among individual agents. Not taking into account recent progress and addressing these concerns separately, there remains a lack of solutions offering theoretical guarantees for both privacy protection and constrained ZOO over time-varying unbalanced *** hereby propose a novel algorithm, termed the differential privacy(DP) distributed push-sum based zeroth-order constrained optimization algorithm(DP-ZOCOA). Operating over time-varying unbalanced graphs, DP-ZOCOA obviates the need for supplemental suboptimization problem computations, thereby reducing overhead in comparison to distributed primary-dual methods. DP-ZOCOA is specifically tailored to tackle constrained ZOO problems over time-varying unbalanced graphs,offering a guarantee of convergence to the optimal solution while robustly preserving privacy. Moreover, we provide rigorous proofs of convergence and privacy for DP-ZOCOA, underscoring its efficacy in attaining optimal convergence without constraints. To enhance its applicability, we incorporate DP-ZOCOA into the federated learning framework and formulate a decentralized zeroth-order constrained federated learning algorithm(ZOCOA-FL) to address challenges stemming from the timevarying imbalance of communication topology. Finally, the performance and effectiveness of the proposed algorithms are thoroughly evaluated through simulations on distributed least squares(DLS) and decentralized federated learning(DFL) tasks.

关键词： Constrained distributed optimization decentralized federated learning (DFL) differential privacy (DP) time-varying unbalanced graphs zeroth-order gradient

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