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Rapid Growth of Halide Perovskite Single Crystals:From Methods to Optimization Control

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chinese Journal of Chemistry 2019年第6期37卷 616-629页

作者： Yu-ling wang shuai Chang xiao-Mei Chen Yan-Dong Ren li-Fu Shi Yong-Hao liu Hai-Zheng Zhong School of Mechatronics Engineering Daqing Normal UniversityXibin Xi RoadRanghulu DistrictDaqingHeilongjiang 163712China beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic systems School of Materials Science&EngineeringBeijing Institute of TechnologyZhongguancun South StreetHaidian DistrictBeijing 100081China

Metal halide perovskites are emerging as new generation optoelectronic materials due to their high carrier mobility, long carrier diffusion length and large light absorption coefficient, which have broad applications in solar cell, light-emitting diode, laser, photodetector and transistors. Perovskite single crystal is an ideal platform for discerning the intrinsic properties of these materials. In some cases, perovskite single crystals are better candidates to gain high performance optoelectronics. However, the growth of perovskite single crystals is time and cost consuming, which has an obvious disadvantage for device exploration. Therefore, fast growth technique is highly desirable in not only promoting the use of perovskites in commercial applications but also facilitating deep physical investigation of the materials. In this review, we summarize thoroughly the development of fast growth of the halide perovskites single crystal. Specifically, we highlight the progress of rapid growth techniques with emphasis on the optimization control.

关键词： crystal growth semiconductors synthetic methods metal halide perovskite single crystals rapid growth

Reducing feedback load for OFDM-based wireless system

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The Journal of china Universities of Posts and Telecommunications 2013年第2期20卷 25-31页

作者： li Ming-ming wang xiao-xiang ZHOU Jia Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

In this paper, the feedback load reduction problem in wireless systems based on orthogonal frequency division multiplexing （OFDM） is investigated and an opportunistic feedback scheme （OFS） is proposed. The key idea behind OFS is that only the key channel gains which can significantly affect the system throughput are fed back to the BS. Firstly, the key channel gains are proved to belong to a channel gain interval. Secondly, a statistical method is proposed to estimate the channel gain interval. Thirdly, the opportunistic feedback scheme is formulated and the feedback load of OFS is analyzed. The advantage of OFS is threefold： the first is OFS can work in both OFDM-based multicast system and OFDM-based unicast system. The second is the channel fading type of the BS-user link is not required, which is more realistic. The third is OFS can get better feedback load performance compared with other schemes, while achieving almost the same throughput performance compared with that of full feedback scheme.

关键词： OFDM wireless system feedback load reduction multicast system unicast system opportunistic feedback scheme

The ChatGPT After: Building Knowledge Factories for Knowledge Workers with Knowledge Automation

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自动化学报:英文版 2023年第11期10卷 2041-2044页

作者： Yutong wang xiao wang Xingxia wang Jing Yang Oliver Kwan lingxi li Fei-Yue wang State Key Laboratory for Management and Control of Complex systems Chinese Academy of SciencesBeijing 100190China School of Artificial Intelligence Anhui UniversityHefei 230039China Motion G Inc068898Singapore Department of Electrical and Computer Engineering Purdue School of Engineering and TechnologyIndiana University-Purdue University IndianapolisIndiana 46202-5132 USA IEEE

Briefing: This perspective introduces the concept and framework of knowledge factories with knowledge machines for knowledge workers to achieve knowledge automation for Industry 5.0 and intelligent *** The big hit of Chat GPT makes it imperative to contemplate the practical applications of big or foundation models [1]-[5]. However, as compared to conventional models, there is now an increasingly urgent need for foundation intelligence of foundation models for real-world industrial applications.

关键词： Automation template Chat GPT

Heat stress on calves and heifers: a review

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Journal of Animal science and Biotechnology 2020年第4期11卷 929-936页

作者： Jingjun wang Jinghui li Fengxia wang Jianxin xiao Yajing wang Hongjian Yang Shengli li Zhijun Cao State Key Laboratory of Animal Nutrition Beijing Engineering Technology Research Center of Raw Milk Quality and Safety ControlCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193PR China Department of Animal science University of CaliforniaDavisCalifornia 95616USA beijing CNAgri Animal science Technology Research Center Beijing 100193PR China.

The current review is designed with aims to highlight the impact of heat stress(HS) on calves and heifers and to suggest methods for HS alleviation. HS occurs in animals when heat gain from environment and metabolism surpasses heat loss by radiation, convection, evaporation and conduction. Although calves and heifers are comparatively heat resistant due to less production of metabolic heat and more heat dissipation efficiency, they still suffer from HS to some degree. Dry matter intake and growth performance of calves and heifers are reduced during HS because of redistributing energy to heat regulation through a series of physiological and metabolic responses, such as elevated blood insulin and protein catabolism. Enhanced respiration rate and panting during HS accelerate the loss of CO2, resulting in altered blood acid-base chemistry and respiratory alkalosis. HS-induced alteration in rumen motility and microbiota affects the feed digestibility and rumen fermentation. Decreased luteinizing hormone, estradiol and gonadotrophins due to HS disturb the normal estrus cyclicity, depress follicular development, hence the drop in conception rate. Prenatal HS not only suppresses the embryonic development by the impaired placenta, which results in hypoxia and malnutrition, but also retards the growth, immunity and future milk production of newborn calves. Based on the above challenges, we attempted to describe the possible impacts of HS on growth, health, digestibility and reproduction of calves and heifers. likewise, we also proposed three primary strategies for ameliorating HS consequences. Genetic development and reproductive measures, such as gene selection and embryo transfers, are more likely long-term approaches to enhance heat tolerance. While physical modification of the environment, such as shades and sprinkle systems, is the most common and easily implemented measure to alleviate HS. Additionally, nutritional management is another key approach which could help cal

关键词： Calf Energy Heat stress Heifer Reproduction

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导弹水下发射时喷管的气体流动

推进技术 2001年第1期22卷 61-64页

作者：王晓宏陈义良李潜刘长江中国科学技术大学热科学和能源工程系安徽合肥230026 北京空气动力研究所北京100074

针对导弹水下发射时喷管的气体流动问题 ,建立了水下喷管流的简化模型 ,定性地研究水环境的惯性对水下喷管内气体流动造成的阻滞作用。计算显示受阻滞流量ΔQ及受阻滞时间Δt和喷管的喉部面积At 呈幂函数关系 ,固定其他参数仅改变水深 ,... 详细信息

针对导弹水下发射时喷管的气体流动问题 ,建立了水下喷管流的简化模型 ,定性地研究水环境的惯性对水下喷管内气体流动造成的阻滞作用。计算显示受阻滞流量ΔQ及受阻滞时间Δt和喷管的喉部面积At 呈幂函数关系 ,固定其他参数仅改变水深 ,ΔQ及Δt和进口处气体的滞止压力p0 与当地水下静压之间的压力差也有幂函数关系。结果表明喷管所处的水下深度越大 ,喷管内气体流动受阻滞状况也就越严重 ,而减小喉部面积At 和适当增加膨胀比Ab/At 以及增加滞止压力p0 ,均有助于改善水环境对喷管喷出气体造成的阻滞状况。

关键词：潜射导射水下点火喷管气流数学仿真水下喷管流

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不同抗氧剂体系对聚丙烯加工稳定性的影响

塑料科技 2024年第2期52卷 36-39页

作者：葛喜慧刘义韩李旺孙小杰李亚飞江猛北京低碳清洁能源研究院北京102209 国能新疆化工有限公司新疆乌鲁木齐831499

为改善聚丙烯在挤出加工过程的稳定性,采用熔融挤出技术制备改性聚丙烯,研究抗氧剂种类、抗氧剂配比、水滑石种类对聚丙烯加工稳定性的影响。结果表明:羟胺类抗氧剂与季戊四醇亚磷酸酯类抗氧剂复配,提高聚丙烯的加工稳定性,多次挤出加工... 详细信息

为改善聚丙烯在挤出加工过程的稳定性,采用熔融挤出技术制备改性聚丙烯,研究抗氧剂种类、抗氧剂配比、水滑石种类对聚丙烯加工稳定性的影响。结果表明:羟胺类抗氧剂与季戊四醇亚磷酸酯类抗氧剂复配,提高聚丙烯的加工稳定性,多次挤出加工a值(红绿)小于0,b值(黄蓝)小于1.5,熔体流动速率增量小于5 g/10 min。具有大粒径且分散性好的片状结构水滑石有利于改善聚丙烯的加工稳定性。采用羟胺类抗氧剂、季戊四醇亚磷酸酯类抗氧剂与大粒径分散性好的片状结构水滑石复配,有利于提高聚丙烯的加工稳定性。

关键词：聚丙烯抗氧剂水滑石加工稳定性

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我国空间推进技术领域发展思考与建议

中国工程科学 2024年第3期26卷 217-225页

作者：侯晓李永武志文林庆国汪小卫耿海黄天坤中国航天科技集团有限公司北京100048 北京控制工程研究所北京100094 北京理工大学宇航学院北京100081 上海空间推进研究所上海201112 中国运载火箭技术研究院北京100076 兰州空间技术物理研究所兰州730000

我国空间推进技术领域历经60余年发展形成了较完善的技术体系和较丰富的产品谱系,支持了载人航天、应用卫星、深空探测等重大工程应用;面向我国航天领域未来规划、重大工程和科学项目的应用需求,空间推进系统现有的技术水平存在不足,亟... 详细信息

我国空间推进技术领域历经60余年发展形成了较完善的技术体系和较丰富的产品谱系,支持了载人航天、应用卫星、深空探测等重大工程应用;面向我国航天领域未来规划、重大工程和科学项目的应用需求,空间推进系统现有的技术水平存在不足,亟需谋划创新发展和突破方向。本文从电推进、化学推进、核推进、新概念空间推进等角度出发,系统梳理了空间推进系统的发展现状;重点提炼了高性能、低成本的空间推进系统支撑低轨小卫星组网发展,大推力、可重复使用的低温化学推进技术推动新型空间运输系统发展,多类型、长寿命的空间推进技术保障深空关键应用等未来应用需求。研究认为,我国空间推进技术领域面临系统可靠性和寿命亟需进一步提高、部分领域的产品成熟度与国际先进水平差距明显、产品成本高、可选推进技术种类少且重点技术研究滞后等迫切挑战,需开展顶层规划、优化技术选择,重视基础研究、构建发展机制,在重点技术方向上分类推进科研攻关,尽快实现低轨小卫星、地月空间转移、深空探测(含载人航天)用推进系统的技术突破与在轨应用。

关键词：空间推进电推进核推进低轨小卫星空间运输深空探测重复使用

Online Clustering for Wind Speed Forecasting Based on Combination of RBF Neural Network and Persistence Method

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Online Clustering for Wind Speed Forecasting Based on Combin...

Review on recent progress in on-line monitoring technology for atmospheric pollution source emissions in china

2011 chinese Control and Decision Conference（CCDC）

作者： xiao Qin is with Department of Automation,Tsinghua University,beijing,china.Cong Jiang is with Department of systems Engineering and Engineering Management,The chinese University of Hong Kong,Shatin,Hong Kong SAR,china.Jun wang is with Department of Control science and Engineering,Tongji University,Shanghai,china.

This paper proposes an online clustering algorithm for wind speed *** algorithm combines the persistence method and the RBF neural network,and chooses an appropriate method according to different wind *** simulations demonstrate that this algorithm can more accurately predict wind speed than either of the single methods and therefore is more effective for wind speed forecasting.

关键词： Wind speed prediction Combination forecasting On-line prediction Clustering algorithm

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Journal of Environmental sciences 2023年第1期123卷 367-386页

作者： Huanqin wang Jitong Zhou Xue li Qiang ling Hongyuan Wei Lei Gao Ying He Ming Zhu xiao xiao Youjiang liu Shan li Chilai Chen Guotao Duan Zhimin Peng Peili Zhou Yufeng Duan Jianbing wang Tongzhu Yu Yixin Yang Jiguang wang Zhen Zhou Huaqiao Gui Yanjun Ding State Key Laboratory of Transducer Technology Institute of Intelligent MachinesHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Institute of Mass Spectrometry and Atmospheric Environment Jinan UniversityGuangzhou 510632China Department of Automation University of Science and Technology of ChinaHefei 230027China china Automotive Technology and Research Center Tianjin 300300China Institute of Solid State Physics Chinese Academy of SciencesHefei 230031China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhan 430074China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Power systems Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Emissions from mobile sources and stationary sources contribute to atmospheric pollution in china,and its components,which include ultrafine particles(UFPs),volatile organic compounds(VOCs),and other reactive gases,such as NH3and NOx,are the most harmful to human *** has released various regulations and standards to address pollution from mobile and stationary ***,it is urgent to develop online monitoring technology for atmospheric pollution source *** study provides an overview of the main progress in mobile and stationary source monitoring technology in china and describes the comprehensive application of some typical instruments in vital areas in recent *** instruments have been applied to monitor emissions from motor vehicles,ships,airports,the chemical industry,and electric power *** only has the level of atmospheric environment monitoring technology and equipment been improving,but relevant regulations and standards have also been constantly ***,the developed instruments can provide scientific assistance for the successful implementation of *** to the potential problem areas in atmospheric pollution in china,some research hotspots and future trends of atmospheric online monitoring technology are ***,more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.

关键词： Atmospheric pollution Mobile sources Stationary sources On-line monitoring technology