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China Communications 2024年第2期21卷 227-244页

作者： meng meng Bo Hu Shanzhi Chen Jianyin Zhang State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Wireless Mobile Communication China Academy of Telecommunication TechnologyBeijing 100191China Research Institute of China Mobile Beijing 100053China

Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system *** optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method ***, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput.

关键词： convex optimization intelligent reflecting surface LEO satellite communication OFDM

Identifying Comprehensive Genomic Alterations and Potential Neoantigens for Cervical Cancer Immunotherapy in a Cohort of Chinese Squamous Cell Carcinoma of the Cervix

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Biomedical and Environmental Sciences 2024年第6期37卷 565-580页

作者： meng Wu Jialu Zhou Zhe Zhang Yuanguang meng School of Medicine Nankai UniversityTianjin 300071China Department of Obstetrics and Gynecology The First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Obstetrics and Gynecology Chinese PLA Medical SchoolBeijing 100853China Department of Obstetrics and Gynecology The Seventh Medical Center of Chinese PLA General HospitalBeijing 100700China

Objective Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma(CSCC).Methods Whole-exome sequencing was used to identify genomic alterations and potential neoantigens for CSCC *** Sequencing was performed to analyze neoantigen *** Systematic bioinformatics analysis showed that C>T/G>A transitions/transversions were dominant in *** mutations were the most frequent types of somatic mutation in the coding sequence *** signature analysis detected signature 2,signature 6,and signature 7 in CSCC ***3CA,FBXW7,and BICRA were identified as potential driver genes,with BICRA as a newly reported *** variation profiling identified 4,960 potential neoantigens,of which 114 were listed in two neoantigen-related *** The present findings contribute to our understanding of the genomic characteristics of CSCC and provide a foundation for the development of new biotechnology methods for individualized immunotherapy in CSCC.

关键词： Cervical squamous cell carcinoma Genome alteration Neoantigens Immunotherapy

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改性C/C复合材料高温抗氧化研究现状

材料导报 2017年第A1期31卷 396-401页

作者：郭春园闫联生孟祥利西安航天复合材料研究所西安710025

C/C复合材料超高温氧化防护问题严重限制了高超声速飞行器的快速发展。C/C复合材料高温氧化防护措施主要有两种,即涂层技术和基体改性技术。综述了SiC陶瓷改性C/C复合材料以及ZrC、ZrB_2、HfC等超高温陶瓷改性C/C复合材料的研究现状,并... 详细信息

C/C复合材料超高温氧化防护问题严重限制了高超声速飞行器的快速发展。C/C复合材料高温氧化防护措施主要有两种,即涂层技术和基体改性技术。综述了SiC陶瓷改性C/C复合材料以及ZrC、ZrB_2、HfC等超高温陶瓷改性C/C复合材料的研究现状,并对C/C复合材料高温抗氧化研究方向提出了一些见解。

关键词： C/C复合材料基体改性高温抗氧化超高温陶瓷

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消泡剂对陶瓷膜的污染与再生

膜科学与技术 2014年第3期34卷 104-109页

作者：宋纪双赵民孟祥丽南京工业大学化学化工学院南京210009 立宇化学技术(郑州)有限公司郑州450001

陶瓷膜分离技术是目前国际上最新型的膜分离技术之一,可应用于生物发酵等工业过程中.通常这样的工业过程中涉及到搅拌都会产生泡沫,但是泡沫的产生对生产有不利影响,需要用到消泡剂消除泡沫.文章旨在研究消泡剂是否对陶瓷膜造成污染,消... 详细信息

陶瓷膜分离技术是目前国际上最新型的膜分离技术之一,可应用于生物发酵等工业过程中.通常这样的工业过程中涉及到搅拌都会产生泡沫,但是泡沫的产生对生产有不利影响,需要用到消泡剂消除泡沫.文章旨在研究消泡剂是否对陶瓷膜造成污染,消泡剂对陶瓷膜的污染机理,并寻求解决膜污染的清洗方案.实验结果表明,消泡剂在40℃下对陶瓷膜过滤造成了污染,聚醚消泡剂中PPG-4000污染最严重,有机硅消泡剂中道康宁1410污染最严重.使用0.5%D3-Ultra10碱性清洗剂和0.2%D3-Ultra75酸性清洗剂对污染后的陶瓷膜进行碱洗酸洗,能使膜通量得到很好的恢复.

关键词：陶瓷膜消泡剂膜污染膜清洗

C/C–ZrB_2–SiC复合材料的制备及其性能

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硅酸盐学报 2016年第7期44卷 1002-1007页

作者：张强赵景鹏崔红孟祥利杨星闫联生西北工业大学材料学院西安710072 西安航天复合材料研究所

结合化学气相渗透工艺(chemical vapor infiltration)与前驱体浸渍裂解(precursor infiltration and pyrolysis,PIP)工艺,制备了C/C–Zr B_2–Si C复合材料,并对材料的力学性能和烧蚀性能进行了分析。结果表明:PIP工艺制备的C/C–Zr B_2–Si C复合材料的拉伸、弯曲及剪切强度分别为91.2、214和35.8 MPa,优于通过浆料浸渍工艺制备的复合材料。同时,热流3 200 k W/m^2,时间600 s的氧乙炔火焰试验表明,PIP工艺制备的C/C–Zr B_2–Si C复合材料具有良好的抗氧化烧蚀性能,其线烧蚀率和质量烧蚀率分别为0.002 mm/s和0.7 mg/s。

关键词：复合材料二硼化锆前驱体浸渍裂解力学性能烧蚀性能

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利用稳健非负矩阵分解实现无监督高光谱解混

中国图象图形学报 2020年第4期25卷 801-812页

作者：宋晓瑞吴玲达孟祥利航天工程大学复杂电子系统仿真实验室北京101416

目的基于非负矩阵分解的高光谱图像无监督解混算法普遍存在着目标函数对噪声敏感、在低信噪比条件下端元提取和丰度估计性能不佳的缺点。因此,提出一种基于稳健非负矩阵分解的高光谱图像混合像元分解算法。方法首先在传统基于非负矩阵... 详细信息

目的基于非负矩阵分解的高光谱图像无监督解混算法普遍存在着目标函数对噪声敏感、在低信噪比条件下端元提取和丰度估计性能不佳的缺点。因此,提出一种基于稳健非负矩阵分解的高光谱图像混合像元分解算法。方法首先在传统基于非负矩阵分解的解混算法基础上,对目标函数加以改进,用更加稳健的L1范数作为重建误差项,提高算法对噪声的适应能力,得到新的无监督解混目标函数。针对新目标函数的非凸特性,利用梯度下降法对端元矩阵和丰度矩阵交替迭代求解,进而完成优化求解,得到端元和丰度估计值。结果分别利用模拟和真实高光谱数据,对算法性能进行定性和定量分析。在模拟数据集中,将本文算法与具有代表性的5种无监督解混算法进行比较,相比于对比算法中最优者,本文算法在典型信噪比20 dB下,光谱角距离(spectral angle distance,SAD)增大了10.5%,信号重构误差(signal to reconstruction error,SRE)减小了9.3%;在真实数据集中,利用光谱库中的地物光谱特征验证本文算法端元提取质量,并利用真实地物分布定性分析丰度估计结果。结论提出的基于稳健非负矩阵分解的高光谱无监督解混算法,在低信噪比条件下,能够获得较好的端元提取和丰度估计精度,解混效果更好。

关键词：非负矩阵分解无监督混合像元分解端元提取丰度估计高光谱图像

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一种海上风电风机基础导管架建造施工方法

天津科技 2022年第8期49卷 68-72页

作者：孟祥礼中海福陆重工有限公司广东珠海519000

以中节能阳江南鹏岛300 MW海上风电项目风机基础导管架的建造过程为例,介绍一种导管架的建造方法。通过对其建造过程的研究,包括项目分解、施工流程、运输方式等,以期为后续类似工程提供借鉴。该项目采用将风电导管架分为过渡段、上部... 详细信息

以中节能阳江南鹏岛300 MW海上风电项目风机基础导管架的建造过程为例,介绍一种导管架的建造方法。通过对其建造过程的研究,包括项目分解、施工流程、运输方式等,以期为后续类似工程提供借鉴。该项目采用将风电导管架分为过渡段、上部导管架、下部导管架3部分并同时进行施工,最后在总装室外场地进行总装的方案,其突出的优点是多点同时施工,有利于缩短施工周期,降低了总装所需大型吊机和辅助设备的规格和数量,节约了项目成本。

关键词：海上风电导管架立式建造

A multiscale adaptive framework based on convolutional neural network: Application to fluid catalytic cracking product yield prediction

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Petroleum Science 2024年第4期21卷 2849-2869页

作者： Nan Liu Chun-meng Zhu meng-Xuan Zhang Xing-Ying Lan State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) College of Artificial Intelligence China University of Petroleum (Beijing)

Since chemical processes are highly non-linear and multiscale, it is vital to deeply mine the multiscale coupling relationships embedded in the massive process data for the prediction and anomaly tracing of crucial process parameters and production indicators. While the integrated method of adaptive signal decomposition combined with time series models could effectively predict process variables, it does have limitations in capturing the high-frequency detail of the operation state when applied to complex chemical processes. In light of this, a novel Multiscale Multi-radius Multi-step Convolutional Neural Network(Msrt Net) is proposed for mining spatiotemporal multiscale information. First, the industrial data from the Fluid Catalytic Cracking(FCC) process decomposition using Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN) extract the multi-energy scale information of the feature subset. Then, convolution kernels with varying stride and padding structures are established to decouple the long-period operation process information encapsulated within the multi-energy scale data. Finally, a reconciliation network is trained to reconstruct the multiscale prediction results and obtain the final output. Msrt Net is initially assessed for its capability to untangle the spatiotemporal multiscale relationships among variables in the Tennessee Eastman Process(TEP). Subsequently, the performance of Msrt Net is evaluated in predicting product yield for a 2.80 × 10～6 t/a FCC unit, taking diesel and gasoline yield as examples. In conclusion, Msrt Net can decouple and effectively extract spatiotemporal multiscale information from chemical process data and achieve a approximately reduction of 30% in prediction error compared to other time-series models. Furthermore, its robustness and transferability underscore its promising potential for broader applications.

关键词： Fluid catalytic cracking Product yield Data-driven modeling Multiscale prediction Data decomposition Convolution neural network

Progress and challenges of electrolyte modulation in aqueous zinc-ion batteries

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Rare Metals 2024年第7期43卷 2940-2967页

作者： Qi-Hang Yang Lu-Fei Wang Xiao-Yu Wang meng-meng Zhen Tianjin Key Laboratory of Clean Energy and Pollution Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300071China

As a new type of green battery system,aqueous zinc-ion batteries(AZIBs)have gradually become a research hotspot due to their low cost,high safety,excellent stability,high theoretical capacity(820 mAh·g^(-1))of zinc anode,and low redox potential(-0.76 V *** hydrogen electrode(SHE)).AZIBs have been expected to be an alternative to lithium-ion batteries for large-scale commercial energy storage ***,they are facing thorny issues such as degradation of cycling performance,zinc dendrites,and side *** the same time,these problems cause short cycling life of batteries,thus severely limiting their commercial *** recent years,many more researches have been conducted on the modification of anode and cathode materials of AZIBs,but there is a lack of in-depth discussion on the characteristics and mechanism of electrolyte *** this review,we will make a systematic summary of the current problems with two electrodes in AZIBs,as well as the types and functions of electrolyte ***,we further systematically describe the modulation mechanism of electrolyte additives in the performance of the cathode and *** prospects and development directions of additive modulation strategies for AZIBs electrolytes are prospected.

关键词： Electrolyte additives Aqueous zinc-ion batteries Zinc anode protection Cathode chemistry

Output Feedback Stabilization of High-Order Nonlinear Time-Delay Systems With Low-Order and High-Order Nonlinearities

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1304-1306页

作者： meng-meng Jiang Kemei Zhang Xue-Jun Xie School of Mathematics Science Liaocheng UniversityLiaocheng 252059China School of Mathematics Science Qufu Normal UniversityQufu 273165China Institute of Automation Qufu Normal UniversityQufu 273165China

Dear Editor,to This letter deals with the output feedback stabilization of a class of high-order nonlinear time-delay systems with more general low-order and high-order *** constructing reduced-order observer,based on homogeneous domination theory together with the adding a power integrator method,an output feedback controller is developed guarantee the equilibrium of the closed system globally uniformly asymptotically stable.

关键词： Nonlinear stabilization guarantee