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Subcarrier-Abstracted Multi-frequency Constant-Envelope Multiplexing and Its Implementation Optimization

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Subcarrier-Abstracted Multi-frequency Constant-Envelope Mult...

Droplet manipulation and Crystallization Regulation in Inkjet-Printed Perovskite Film Formation

第九届中国卫星导航学术年会

作者： junjie ma Zheng Yao Mingquan Lu Department of Electronic Engineering Tsinghua University

More and more signals are broadcast by navigation satellite systems nowadays to satisfy users’ diversified needs in positioning,navigation and timing(PNT).We usually adopt multiplexing techniques to combine several signals into an integrated signal to save transmission link *** the high-power amplifier on satellite operates at the nonlinear saturation region,the multiplexed signal is required to have constant-envelope *** present,single frequency constant-envelope multiplexing(CEM) techniques have been studied ***,the research in multi-frequency constant-envelope multiplexing still needs to be *** this paper,we propose a subcarrier-abstracted multi-frequency constant-envelope multiplexing(SAMCEM) *** substitute the continuous sinusoidal subcarrier by step-shape subcarrier,and construct the signal space using the view of *** on these mathematical preliminaries,we set up an optimization problem,which maximizes multiplexing efficiency under the constraint of constant *** output of our method is a phase look-up table(LUT).Our method breaks the limitations in subcarriers,the number of signals,and power and phase relationship among signals,overcoming drawbacks of the existing multi-frequency multiplexing techniques with better flexibility and universality and can achieve optimal multiplexing *** technique serves as a candidate technique to support the improvement in signal scheme of BDS *** this paper,we also improve the engineering implementation of multi-frequency CEM.A low-redundancy LUT storage scheme is proposed,which can save half of the storage resource in dual-frequency ***,pipeline structure is adopted to generate multi-frequency CEM signals,which can help avoid transmitted phase error in multi-frequency CEM.

关键词： Multi-frequency constant-envelope multiplexing Subcarrier Orthogonal basis Multiplexing efficiency Pipeline

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CCS Chemistry 2022年第5期4卷 1465-1485页

作者： Yajie Cheng Hangjuan Wu junjie ma Pengwei Li Zhenkun Gu Shuangquan Zang Liyuan Han Yiqiang Zhang Yanlin Song School of materials Science and Engineering Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001 College of Chemistry Zhengzhou UniversityZhengzhou 450001 State Key Laboratory of Metal matrix Composites Shanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190

Emerging organic–inorganic metal halide perovskite materials have become the focus of the optoelectronics research community owing to their excellent photoelectric ***,challenges still exist for transferring the lab-made devices to largearea industrial *** printing(IJP)technology provides a promising way to fill the gap because of its precise droplet control and uniform large-scale deposition ***,an in-depth understanding of inkjet-printed perovskite films in terms of droplet manipulation and crystallization regulation is critical for upscaling the perovskite devices to commercial *** this review,we give an overview of inkjet-printed high-quality perovskite films and provide guidelines on inkjet-printing large-scale highperformance perovskite ***,we analyze theories of droplet formation and perovskite nucleation/crystallization dynamics and then focus on summarizing the perovskite film-formation strategies via IJP,in the aspects of ink engineering,the printing process,and ***,we review the recent advances of inkjet-printed perovskite films on optoelectronic devices,such as perovskite solar cells,perovskite light-emitting diodes,and perovskite ***,we highlight the“Trilogy Strategies,”including ink engineering,printing process,and posttreatment for printing high-quality perovskite films.

关键词： inkjet printing perovskite droplet manipulation crystallization film formation optoelectronic devices

Evaluation and spatio-temporal analysis of surface energy flux in permafrost regions over the Qinghai-Tibet Plateau and Arctic using CMIP6 models

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International Journal of Digital Earth 2022年第1期15卷 1947-1965页

作者： junjie ma Ren Li Zhongwei Huang Tonghua Wu Xiaodong Wu Lin Zhao Hongchao Liu Guojie Hu Yao Xiao Yizhen Du Shuhua Yang Wenhao Liu Yongliang Jiao Shenning Wang Cryosphere Research Station on the Qinghai-Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhouPeople’s Republic of China School of Geographical Sciences Nanjing University of Information Science & TechnologyNanjingPeople’s Republic of China Zaozhuang University ZaozhuangPeople’s Republic of China

The surface energy budget over the Qinghai-Tibet Plateau(QTP)and the Arctic significantly influences the climate system with global *** performances of 30 selected Coupled Model Intercomparison Project Phase 6(CMIP6)models were evaluated based on six sites in the QTP and *** simulation results for latent heat flux(LE)were more accurate in the QTP,where the correlation coefficient and root mean square error(RMSE)were 0.9 and 30 W m−2,*** results for sensible heat flux(H)were more accurate in the Arctic,the correlation coefficient and RMSE were 0.8 and 24 W m−2,***,the multiple models mean results revealed that the surface energy flux had seasonal variation and regional differences over the QTP and the *** the QTP,H was the lowest in winter,increased in spring,and reached the maximum in ***,the transitional changes in spring and autumn were not apparent in the Arctic,mainly due to seasonal net radiation difference between the two *** was affected by precipitation and surface soil moisture *** work is important for understanding land-atmosphere interactions and useful for improving the accuracy of land surface models simulations.

关键词： Qinghai-Tibet Plateau Arctic surface energy budget permafrost

Highly efficient and stable planar perovskite solar cells with large-scale manufacture and low-cost SnO2 layer towards commercialization viable

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Highly efficient and stable planar perovskite solar cells wi...

第四届新型太阳能电池学术研讨会

作者： junjie ma Xiaolu Zheng Hongwei Lei Guojia Fang School of Physics and Technology Wuhan University

The past five years have seen the remarkable rise of a new type of hybrid perovskite solar cells(PSCs).However, there still remain challenges for PSCs towards large-scale application and *** main reasons are the instability of the perovskite film and the lack of large-scale and low-cost manufacture techniques for electron transfer layer(ETL).Tin oxide(SnO) has emerged as a promising candidate for ETL, however, systematic exploration of its commercialized application in PSCs is still ***, we prepared SnO ETL through the electron beam evaporation(e-beam) technology,realizing large-scale,low-cost and uniform manufacture which would be available for industrial deployment.A Cs-containing blended perovskite absorber layer was introduced into the PSCs to effectively enhance the ambient *** a result, PSCs exhibit a high efficiency of 18.2% without any interface modification, and remarkable long-term stability, which remained 97% of its initial PCE after being stored over 34 *** result demonstrated the great potential of the PSCs based on SnO ETL towards commercially viable.

关键词： perovskite solar cells electron beam evaporation SnO2 commercialization

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无线传感网络测量的目标预测动态能量优化

机械工程学报 2007年第8期43卷 26-31页

作者：王雪马俊杰王晟清华大学精密测试技术及仪器国家重点实验室北京100084

能量约束是无线传感网络实际应用的关键问题之一。针对无线传感网络测量的能效性问题,提出目标预测动态能量优化方法,采用粒子滤波算法对测量目标状态进行预测,通过动态唤醒无线传感节点延长节点睡眠时间节省节点能量。根据无线传感网... 详细信息

能量约束是无线传感网络实际应用的关键问题之一。针对无线传感网络测量的能效性问题,提出目标预测动态能量优化方法,采用粒子滤波算法对测量目标状态进行预测,通过动态唤醒无线传感节点延长节点睡眠时间节省节点能量。根据无线传感网络节点分布计算能力,运用分布式遗传模拟退火算法优化目标测量过程,使网络能耗最小化。重点讨论机动目标跟踪应用,实现目标位置预测、节点睡眠状态规划和测量节点优化选择,提出节省通信能量的中转节点路由方案。机动目标跟踪的仿真试验表明,目标预测动态能量优化方法能降低节点能耗,并提高无线传感网络的能量有效性。

关键词：无线传感网络动态能量控制能效性粒子滤波

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新见吐鲁番出土“入老”文书考释

西域研究 2023年第3期 56-66,175页

作者：马俊杰中国政法大学法律古籍研究所

新见《高昌延寿十五年(638)羁人袁虫子上启为乞入老免役事》是麹氏高昌国时期的一件世子令,不同于以往发现的王令。该令应“入老”事务而产生,事主身份为具有高昌特色的“羁人”,不仅在制度层面揭示了麹氏高昌的地方特色,更诠释了其与... 详细信息

新见《高昌延寿十五年(638)羁人袁虫子上启为乞入老免役事》是麹氏高昌国时期的一件世子令,不同于以往发现的王令。该令应“入老”事务而产生,事主身份为具有高昌特色的“羁人”,不仅在制度层面揭示了麹氏高昌的地方特色,更诠释了其与中原文化的血肉联系。此外,世子令的发现也丰富了麹氏高昌文书行政的研究类型,还为考察同时期其他中原王朝属国的地方治理提供了有益参考。

关键词：入老入养王令世子令麹氏高昌

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甲午年北洋舰队援旅问题新探

历史档案 1999年第1期12卷 109-115,119页

作者：马骏杰

中日甲午战争中，中国在辽东半岛战役中的失败，使战略要地旅顺失守，渤海门户洞开，加速了中国失败的进程。由于北洋舰队没有全力援救旅顺，因而不仅在当时遭到朝野的普遍责难，而且还一直为后人所诟病。近年来，学术界对北洋舰队援旅... 详细信息

中日甲午战争中，中国在辽东半岛战役中的失败，使战略要地旅顺失守，渤海门户洞开，加速了中国失败的进程。由于北洋舰队没有全力援救旅顺，因而不仅在当时遭到朝野的普遍责难，而且还一直为后人所诟病。近年来，学术界对北洋舰队援旅问题有了更加深入的研究，提出了许多新的?（共8页)

关键词：北洋舰队丁汝昌李鸿章旅顺口黄海海战运兵船辽东半岛大连湾花园口日本

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泛在电力物联网在电力设备状态监测中的应用

电力系统保护与控制 2020年第14期48卷 69-75页

作者：刘喜梅马俊杰青岛科技大学自动化与电子工程学院山东青岛266061

随着信息化水平的不断发展,泛在电力物联网的建设提上日程,这对提升变电站电力设备在线监测水平,推动智能电网发展具有重要的指导意义。对基于物联网的电力设备状态监测系统进行了研究,概括了泛在电力物联网在线监测系统的体系结构和特... 详细信息

随着信息化水平的不断发展,泛在电力物联网的建设提上日程,这对提升变电站电力设备在线监测水平,推动智能电网发展具有重要的指导意义。对基于物联网的电力设备状态监测系统进行了研究,概括了泛在电力物联网在线监测系统的体系结构和特征。根据变电站电力设备状态在线监测的需求,探索研究了红外热成像监测子系统和变电站环境监测子系统的系统构成,实现了对电力设备状态监测系统的优化设计。指导变电站电力设备状态监测系统的规划、设计和建设,具有十分广阔的应用前景。

关键词：信息化泛在电力物联网电力设备状态监测红外热成像监测变电站环境监测

西凉秀才策试制度研究--以《建初四年(408)秀才对策文》为中心

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西域研究 2020年第2期 82-95,171,172页

作者：马俊杰中国人民大学国学院

《西凉建初四年秀才对策文》是目前所见最早的关于察举制度的实物资料。以往的研究侧重于策文的思想内容、秀才的士族身份等问题,事实上该文书还揭示了秀才策试制度的程序、公文体式等多方面的信息。它是王国体制下选官制度的产物,为我... 详细信息

《西凉建初四年秀才对策文》是目前所见最早的关于察举制度的实物资料。以往的研究侧重于策文的思想内容、秀才的士族身份等问题,事实上该文书还揭示了秀才策试制度的程序、公文体式等多方面的信息。它是王国体制下选官制度的产物,为我们如今研究北朝地方政权的政治文化生态,以及中古政治和文化关系提供了新的资料。本文从该文书的书写形态出发,通过对公文体式的微观考察进一步揭示该文书的性质,以期对汉晋以来察举制度进行更直观、具体的考察。

关键词：副之端门秀才对策贤良对策王国体制大一统