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Integrated spatial-temporal random speckle spectrometer with high resolution in the C-band

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Photonics Research 2024年第7期12卷 1556-1563页

作者： SHIBO XU JIAHUI zhang junwei cheng JIANJI DONG Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

The increasing demand for diverse portable high-precision spectral analysis applications has driven the rapid development of spectrometer miniaturization. However, the resolutions of existing miniaturized spectrometers mostly remain at the nanometer level, posing a challenge for further enhancement towards achieving picometerlevel precision. Here, we propose an integrated reconstructive spectrometer that utilizes Mach–Zehnder interferometers and a tunable diffraction network. Through random tuning in the time domain and disordered diffraction in the space domain, the random speckle patterns closely related to wavelength information are obtained to construct the transmission matrix. Experimentally, we achieve a high resolution of 100 pm and precisely reconstruct multiple narrowband and broadband spectra. Moreover, the proposed spectrometer features a simple structure, strong portability, and fast sampling speed, which has great potential in the practical application of high-precision portable spectral analysis.

关键词： speckle random resolution

Time-space multiplexed photonic-electronic digital multiplier

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Photonics Research 2024年第3期12卷 499-504页

作者： WENKAI zhang BO WU WENTAO GU junwei cheng HAILONG ZHOU LIAO CHEN WENCHAN DONG JIANJI DONG XINLIANG zhang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Optical computing has shown immense application prospects in the post-Moore ***,as a crucial component of logic computing,the digital multiplier can only be realized on a small scale in optics,restrained by the limited functionalities and inevitable loss of optical *** this paper,we propose a time-space multiplexed architecture to realize large-scale photonic-electronic digital multiplication.

关键词： multiplier electronic restrained

Homogeneous permeation and oriented crystallization in nanostructured mesopores for efficient and stable printable mesoscopic perovskite solar cells

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Science China Chemistry 2024年第11期67卷 3688-3696页

作者： Guodong zhang Yanjie cheng Tingting Niu Ziwei Zheng Zongwei Li junwei Xiang Qiaojiao Gao Minghao Xia Lijuan Guo Yiming Liu Mengru zhang Yiran Tao Xueqin Ran Mingjie Li Guichuan Xing Yingdong Xia Lingfeng Chao Anyi Mei Hongwei Han Yonghua Chen Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM) School of Flexible Electronics (Future Technologies) Nanjing Tech University Michael Gr?tzel Center for Mesoscopic Solar Cells Wuhan National Laboratory for Optoelectronics Key Laboratory of Materials Chemistry for Energy Conversion and Storage of Ministry of Education Huazhong University of Science and Technology Department of Physics The Chinese University of Hong Kong Department of Applied Physics The Hong Kong Polytechnic University Shenzhen Research Institute The Hong Kong Polytechnic University Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials Engineering University of Macau

The low-cost and scalable printable mesoporous perovskite solar cells(p-MPSCs) face significant challenges in regulating perovskite crystal growth due to their nanoscale mesoporous scaffold structure, which limits the improvement of device power conversion efficiency(PCE). In particular, the most commonly used solvents, N,N-dimethylformamide(DMF) and dimethyl sulfoxide(DMSO), have a single chemical interaction with the precursor components and high volatility, which is insufficient to self-regulate the perovskite crystallization process, leading to explosive nucleation and limited growth within mesoporous scaffolds. Here, we report a mixed solvent system composed of methylamine formaldehyde(MAFa)-based ionic liquid and acetonitrile(ACN) with the strong C=O–Pb coordination and N–H···I hydrogen bonding with perovskite components. We found that the mixed solvent system is beneficial for the precursor solution to homogeneously penetrate into the mesoporous scaffold,and the strong C=O–Pb coordination and N–H···I hydrogen bonding interaction can promote the oriented growth of perovskite crystals. This synergistic effect increased the PCE of the p-MPSCs from 17.50% to 19.21%, which is one of the highest records for p-MPSC in recent years. Additionally, the devices exhibit positive environmental stability, retaining over 90% of the original PCE after 1,200 h of aging under AM 1.5 illumination conditions at 55 °C and 55% humidity.

关键词： printable mesoscopic perovskite solar cells ionic liquid crytallization control hight efficiency and stability

学习型社区赋能教育强国建设——基于在线学习者关系网络分析视角

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中国电化教育 2024年第6期 38-45页

作者：贺超波林晓凡程俊伟汤庸张倚诺华南师范大学计算机学院广东广州510631 华南师范大学教育信息技术学院广东广州510631

学习型社区建设有助于加快教育强国落地,社区中在线学习者的各种协作互动行为,促进了学习者关系网络的生成。对该网络进行深入分析,可以挖掘其中蕴含的社区学习的本质特征。该研究提出从社区发现角度对学习者关系网络进行分析,首先设计... 详细信息

学习型社区建设有助于加快教育强国落地,社区中在线学习者的各种协作互动行为,促进了学习者关系网络的生成。对该网络进行深入分析,可以挖掘其中蕴含的社区学习的本质特征。该研究提出从社区发现角度对学习者关系网络进行分析,首先设计基于图卷积网络和非负矩阵分解,并集成学习者关系网络信息和文本内容信息的新型学习型社区发现方法,提出四个社区特征度量指标,在真实的学习者关系网络中进行应用分析。结果表明,所提出的分析方法能有效挖掘学习者关系网络存在的学习兴趣主题社区,还可以对社区整体和社区成员个体进行特征分析,并且分析结果可为引导学习者的在线交互协作行为提供决策支持。最后,形成“构建可视化学习型社区—开展社区之间知识分享—促进各社区的互动合作—指标反馈下的反思迭代”的学习型社区赋能策略。通过策略赋能学习型社区高质量发展,以社区新质生产力组合助推教育强国建设。

关键词：学习者关系网络网络分析学习型社区社区发现教育强国

Hybrid Recommendation Based on Graph Embedding

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China Communications 2021年第11期18卷 243-256页

作者： cheng Zeng Haifeng zhang junwei Ren Chaodong Wen Peng He School of Computer Science and Information Engineering Hubei UniversityWuhan 430000China Hubei Province Engineering Technology Research Center for Software Engineering Wuhan 430000China Hubei Engineering Research Center for Smart Government and Artificial Intelligence Wuhan 430000China

In recent years,online reservation systems of country hotel have become increasingly popular in rural *** to accurately recommend the houses of country hotel to the users is an urgent problem to be *** at the problem of cold start and data sparseness in recommendation,a Hybrid Recommendation method based on Graph Embedding(HRGE)is ***,three types of network are built,including user-user network based on user tag,househouse network based on house tag,and user-user network based on user ***,by using the method of graph embedding,three types of network are respectively embedded into low-dimensional vectors to obtain the characterization vectors of ***,these characterization vectors are used to make a hybrid *** datasets in this paper are derived from the Country Hotel Reservation System in Guizhou *** experimental results show that,compared with traditional recommendation algorithms,the comprehensive evaluation index(F1)of the HRGE is improved by 20% and the Mean Average Precision(MAP)is increased by 11%.

关键词： graph embedding hybrid recommendation collaborative filtering tagging

Stress-unloading and gas migration improvement mechanism in the soft and hard interbedded coal seam using directional hydraulic flushing technology

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International Journal of Mining Science and Technology 2023年第9期33卷 1165-1179页

作者： Hao zhang Yuanping cheng Cunbao Deng Jingyu Jiang Lei zhang Xiaoyu Yan junwei Guo Suifang Wang College of Safety&Emergency Management Engineering Taiyuan University of TechnologyTaiyuan 030024China Datong Coal Mine Group Co. LtdDatong 037037China Key Laboratory of Coal Methane and Fire Control Ministry of EducationChina University of Mining and TechnologyXuzhou 221116China National Engineering Research Center for Coal and Gas Control China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

To enhance gas drainage in the soft and hard interbedded(SHI)coal seam,it’s necessary to unload the insitu stress and improve its gas migration *** this research,a directional hydraulic flushing(DHF)technology was carried *** stress-unloading and gas migration improvement mechanism was analyzed through numerical simulation,and systematic engineering tests were conducted to verify the gas drainage *** results show that the improvement of gas migration performance in the SHI coal seam is caused by a combined effect of seepage-improving and *** DHF,stress-unloading and plastic failure could be achieved both in the soft coal(SC)sublayer and in the hard coal(HC)***,the gas diffusion capacity improves significantly in the SC sublayer,while the gas seepage capacity improves notably in the HC ***,the stress-unloading and gas migration improvement effect improves with the flushing radius and the thickness of the SC ***,after adopting the DHF technology,the gas drainage effect improved *** borehole number dropped by 49%,the gas drainage ratio increased from 26.0%to 48.2%,and the average coal roadway excavation speed increased from 2.4 to 5.6 m/d.

关键词： Hydraulic flushing Stress-unloading Plastic failure Permeability-increasing Gas migration

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首钢股份3号高炉高富氧冶炼实践

炼铁 2024年第1期43卷 45-48,53页

作者：张俊伟张海滨程洪全贾新王荣刚罗德庆北京首钢股份有限公司炼铁作业部河北迁安064400

对首钢股份3号高炉高富氧冶炼实践进行了总结。3号高炉富氧率由4.74%逐步提高到6.73%,对理论燃烧温度、炉腹煤气量、煤气流分布、煤气利用率等参数的影响较大。为此,操作上进行了相应调整,通过采取管控原燃料质量、调整装料制度、优化... 详细信息

对首钢股份3号高炉高富氧冶炼实践进行了总结。3号高炉富氧率由4.74%逐步提高到6.73%,对理论燃烧温度、炉腹煤气量、煤气流分布、煤气利用率等参数的影响较大。为此,操作上进行了相应调整,通过采取管控原燃料质量、调整装料制度、优化送风制度、调控热制度及改善出铁操作等措施,理论燃烧温度维持在2100℃左右,炉腹煤气量指数控制在60.5~62.5m/min,煤气利用率提高至50.7%左右。3号高炉主要技术经济指标稳步改善,利用系数最高达到2.54V(m^(3)·d),焦比降至320kg/t。

关键词：大型高炉富氧率理论燃烧温度炉腹煤气量操作制度

711例艾滋病合并结核病患者营养风险发生情况调查

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中国艾滋病性病 2024年第4期30卷 372-376页

作者：张爱华许萌杨宇英马丹丹程俊伟张歌任鹏飞江华河南省传染病医院(郑州市第六人民医院) 郑州450015 北京大学护理学院北京100191

目的分析河南省艾滋病合并结核病患者的营养风险发生情况及影响因素。方法回顾性收集2019年1月至2022年12月在河南省某传染病专科医院住院的711例艾滋病合并结核病患者的临床病例资料,分析其营养风险发生情况及其影响因素。结果河南... 详细信息

目的分析河南省艾滋病合并结核病患者的营养风险发生情况及影响因素。方法回顾性收集2019年1月至2022年12月在河南省某传染病专科医院住院的711例艾滋病合并结核病患者的临床病例资料,分析其营养风险发生情况及其影响因素。结果河南省711例艾滋病合并结核病患者营养风险发生率为70.3%(500例)。年龄>60岁(OR=2.609,95%CI:1.375~4.949)、有吸烟史(OR=2.411,95%CI:1.617~3.595)、痰涂片/培养阳性(OR=1.919,95%CI:1.200~3.067)的患者营养风险发生率较高,居住地非农村(OR=0.125,95%CI:0.031~0.500)、HIV感染确诊时长≥6个月(OR=0.532,95%CI:0.336~0.844)、CD4细胞计数>200个/μL(OR=0.191,95%CI:0.095~0.383)的患者营养风险发生率较低(P60岁、有吸烟史、居住在农村、HIV感染确诊时长<6个月、痰涂片/培养阳性、CD4细胞计数≤200个/μL的患者,为其制定并实施科学、合理的干预措施,以降低营养风险发生率。

关键词：艾滋病结核病营养

分布式交直流混联系统及自适应动态下垂技术研究

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工业仪表与自动化装置 2024年第2期 136-142页

作者：王林董雪张俊伟成月良张泽成张波国华(乳山)新能源有限公司山东威海264500 山东国华时代投资发展有限公司山东济南250002 国电南瑞南京控制系统有限公司江苏南京211100

分布式交直流混联系统采用配电多区柔性组网技术及消纳提升策略,为分布式新能并网接入与潮流优化调度提供了高效可行手段。针对源荷功率消纳需求,首先提出分布式交直流系统架构及其能量管控运行模式,然后通过分析分布式交直流系统的等... 详细信息

分布式交直流混联系统采用配电多区柔性组网技术及消纳提升策略,为分布式新能并网接入与潮流优化调度提供了高效可行手段。针对源荷功率消纳需求,首先提出分布式交直流系统架构及其能量管控运行模式,然后通过分析分布式交直流系统的等效数学模型及工频与高频环流的产生机理,提出考虑功率均衡控制和高频环流抑制的自适应动态下垂控制技术。最后,在PSCAD/EMTDC中搭建了分布式交直流系统的仿真模型并进行算例验证,仿真结果表明所提技术可在保持系统稳定性基础上实现源荷消纳提升和潮流优化调控。

关键词：分布式交直流柔性组网自适应动态下垂高频环流