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基于LSSVR与灰色理论的急倾斜巨厚煤层群开采冒落高度与时滞特征研究

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岩石力学与工程学报 2024年第4期43卷 822-837页

作者：崔峰何仕凤来兴平刘旭东蒋新军孙秉成贾冲宗程李宜霏西安科技大学能源学院陕西西安710054 西安科技大学教育部西部矿井开采及灾害防治重点实验室陕西西安710054 自然资源部煤炭资源勘查与综合利用重点实验室陕西西安710021 国家能源集团新疆能源有限责任公司新疆乌鲁木齐830027

急倾斜巨厚煤层群水平分段开采易诱发顶板冒落且具有时滞特点,掌握上覆岩层的冒落高度与冒落特征对顶板灾害、裂隙发育和地表塌陷的监测至关重要。为此采用相似模拟实验、机器学习和灰色理论等方法,探究覆岩冒落特征与地表塌陷规律,获... 详细信息

急倾斜巨厚煤层群水平分段开采易诱发顶板冒落且具有时滞特点,掌握上覆岩层的冒落高度与冒落特征对顶板灾害、裂隙发育和地表塌陷的监测至关重要。为此采用相似模拟实验、机器学习和灰色理论等方法,探究覆岩冒落特征与地表塌陷规律,获取与冒落高度相关的数据指标,以主成分(PCA)分析法对输入数据进行降维处理,通过遗传算法(GA)结合留一交叉验证法优化训练最小二乘支持向量回归(LSSVR)网络建立冒落高度预测模型(PCA-GA-LSSVR)。以开采参数和监测指标对多种组合的预测模型展开训练和测试,评估优选出最佳预测模型并进行工程检验。研究结果表明:在急倾斜巨厚煤层水平分段开采实验中,随开采深度增加岩层的持续冒落会产生并扩大“V”字型塌陷坑;开采深度、单次垮落高度、模型段高等与冒落高度的相关性较高,各指标参数相互之间存在显著的相关性;实验开采中顶板的冒落具有时滞特征;数据经过降维处理可解决模型输入数据维度高信息重叠的问题,从而提升预测模型的准确率,PCA-GA-LSSVR模型对测试数据的预测结果精度最高,其误差、平均绝对误差和平均绝对百分比误差分别为5.146,4.819,0.087都低于其他模型;灰色时滞OBGM模型对45^(#)煤层冒落高度做出了良好的拟合与预测;在工程检验中,建立的冒落高度预测模型其最大误差波动范围在3.36 m之内,小样本数据环境下增加学习样本能减小模型预测的误差。研究成果为急倾斜煤层水平分段开采冒落高度的研究提供一定的借鉴和参考。

关键词：采矿工程急倾斜煤层水平分段开采冒落高度最小二乘支持向量回归时滞模型

Terahertz topological photonic waveguide switch for on-chip communication

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Photonics Research 2022年第4期10卷 1090-1096页

作者： xudong Liu Jialiang Huang Hao Chen Zhengfang Qian JlNGWEN Ma Xiankai sun Shuting Fan Yiwen sun Department of Biomedical Engineering School of MedicineShenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronics EngineeringShenzhen UniversityShenzhen 518060China Department of Electronic Engineering The Chinese University of Hong KongHong KongChina

Terahertz(THz)topological photonic structures are promising for last-centimeter communication in intra/interchip communication systems because they support bit-error-free THz signal transmission with topological robustness.Active and dynamically tunable THz topological photonic components have not yet been experimentally realized.Here,we experimentally demonstrate a THz topological switch(270-290 GHz)based on a valley Hall photonic crystal structured high-resistivity silicon substrate,in which the THz waves can be dynamically turned on/off by an external 447 nm continuous-wave laser.Our device exhibited an on/off ratio of 19 dB under a pumping light intensity of 240 mW/mm^(2).The 3 dB switching bandwidth was〜60 kHz.

关键词： communication waveguide tunable

Single-cell RNA-Seq reveals transcriptional regulatory networks directing the development of mouse maxillary prominence

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Journal of Genetics and Genomics 2023年第9期50卷 676-687页

作者： Jian sun Yijun Lin Nayoung Ha Jianfei Zhang Weiqi Wang xudong Wang Qian Bian Department of Oral and Cranio-Maxillofacial Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China National Clinical Research Center for Oral Diseases Shanghai Key Laboratory of StomatologyShanghai Research Institute of StomatologyShanghai 200011China Shanghai Institute of Precision Medicine Shanghai 200125China Shanghai Key Laboratory of Reproductive Medicine Shanghai Jiao Tong University School of MedicineShanghai 200025China

During vertebrate embryonic development,neural crest-derived ectomesenchyme within the maxillary prominences undergoes precisely coordinated proliferation and differentiation to give rise to diverse craniofacial structures,such as tooth and palate.However,the transcriptional regulatory networks underpinning such an intricate process have not been fully elucidated.Here,we perform single-cell RNA-Seq to comprehensively characterize the transcriptional dynamics during mouse maxillary development from embryonic day(E)10.5eE14.5.Our single-cell transcriptome atlas of~28,000 cells uncovers mesenchymal cell populations representing distinct differentiating states and reveals their developmental trajectory,suggesting that the segregation of dental from the palatal mesenchyme occurs at E11.5.Moreover,we identify a series of key transcription factors(TFs)associated with mesenchymal fate transitions and deduce the gene regulatory networks directed by these TFs.Collectively,our study provides important resources and insights for achieving a systems-level understanding of craniofacial morphogenesis and abnormality.

关键词： Craniofacial development Single-cell RNA-Seq Maxillary prominences Gene regulatory network Transcription factor

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张家口市明德北街区保护与更新策略研究

城市建筑空间 2024年第3期31卷 63-66页

作者：宋旭东梁玮男孙姜华北京首钢国际工程技术有限公司北方工业大学建筑与艺术学院河北北方学院附属第一医院

随着全社会大力倡导文化自信,公众文化意识越来越强,历史街区保护与更新越来越被人们关注。研究以生态文化学理论为基础,通过对明德北街区现状梳理,发掘其文化、系统、空间、产业现存问题,从物质空间和历史文化方面提出针对性提升与保... 详细信息

随着全社会大力倡导文化自信,公众文化意识越来越强,历史街区保护与更新越来越被人们关注。研究以生态文化学理论为基础,通过对明德北街区现状梳理,发掘其文化、系统、空间、产业现存问题,从物质空间和历史文化方面提出针对性提升与保护策略,以达到提升空间品质的目的。

关键词：生态文化学历史文化街区保护与更新

薄规格高强度工程机械用钢板在线淬火工艺开发

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山东冶金 2024年第2期46卷 11-12,16页

作者：孙正旭张长宏刘旭东莱芜钢铁集团有限公司山东济南271104

通过对薄规格高强度工程机械用钢研发过程中的技术难题进行了分析,并有针对性采取了措施,使得20~29 mm厚度钢板在线淬火工艺得以成功应用。通过对轧制道次的优化提高了轧制板形、通过冷却单元上下水比、边部遮挡优化保证了冷却的均有性... 详细信息

通过对薄规格高强度工程机械用钢研发过程中的技术难题进行了分析,并有针对性采取了措施,使得20~29 mm厚度钢板在线淬火工艺得以成功应用。通过对轧制道次的优化提高了轧制板形、通过冷却单元上下水比、边部遮挡优化保证了冷却的均有性,通过钢板头部跟踪位置优化解决了头部过冷问题,为水冷后板形的改善创造了条件。通过头尾遮挡参数及热处理回火工艺优化,保证了钢板性能的均匀性,实现了薄规格钢板的短流程生产,取得了较好的经济效益和社会效益。

关键词：高强度工程机械用钢调质钢板在线淬火热处理

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胎心仪产品服务体验优化设计策略与实践研究

设计 2024年第7期37卷 60-63页

作者：杜鹤民谈丛睿孙旭东深圳技术大学深圳市龙岗区工业设计协会

随着人民对美好生活需求的日益增长,医疗康养产品设计成为设计研究的热点之一。本文以孕期胎心仪为例,对其开展体验优化的应用性设计研究。首先基于对孕妇群体的深度访谈,总结出两类典型用户画像;其后以服务可视化分析,寻找设计机会点,... 详细信息

随着人民对美好生活需求的日益增长,医疗康养产品设计成为设计研究的热点之一。本文以孕期胎心仪为例,对其开展体验优化的应用性设计研究。首先基于对孕妇群体的深度访谈,总结出两类典型用户画像;其后以服务可视化分析,寻找设计机会点,制订设计策略;最后完成胎心仪设计实践。实践表明,采用服务设计理念对胎心仪产品进行创新设计,能够形成具有深层特征的形态语言,完成体验结构的升级,能为相关产品的开发提供有益参考。

关键词：孕妇胎心仪用户体验设计策略设计实践

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Liquid crystal elastomer composites for soft actuators

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International Journal of Smart and Nano Materials 2023年第4期14卷 440-459页

作者： Jianbo sun Chao Wang Yongjiao Liu xudong Liang Zhijan Wang Aerospace Research Institute of Materials&Processing Technology FengtaiBeijingChina School of Science Harbin Institute of TechnologyShenzhenChina Key Laboratory of Aerospace Advanced Materials and Performance Ministry of EducationSchool of Materials Science and EngineeringBeihang UniversityBeijingChina Tianmushan Laboratory HangzhouChina

Liquid crystal elastomers are active materials that combine the anisotropic properties of liquid crystals with the elasticity of polymer networks.The LCEs exhibit remarkable reversible contraction and elongation capabilities in response to external stimuli,rendering them highly promising for diverse applications,such as soft robotics,haptic devices,shape morphing structures,etc,However,the predominant reliance on heating as the driving stimulus for LCEs has limited their practical applications.This drawback can be effectively addressed by incorporating fllers,which can generate heat under various stimuli.The recent progress in LCE composites has significantly expanded the application potential of LCEs.In this minireview,we present the design strategies for soft actuators with LCE composites,followed by a detailed exploration of photothermal and electrothermal LCE.composites as prominent examples.Furthermore,we provide an outlook on the challenges and opportunities in the feld of LCE composites.

关键词： Liquid crystal elastomers soft actuators soft robots active composites

Siamese Dense Pixel-Level Fusion Network for Real-Time UAV Tracking

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Computers, Materials & Continua 2023年第9期76卷 3219-3238页

作者： Zhenyu Huang Gun Li xudong sun Yong Chen Jie sun Zhangsong Ni Yang Yang Chengdu Fluid Dynamics Innovation Center Chengdu610031China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu611731China

Onboard visual object tracking in unmanned aerial vehicles(UAVs)has attractedmuch interest due to its versatility.Meanwhile,due to high precision,Siamese networks are becoming hot spots in visual object tracking.However,most Siamese trackers fail to balance the tracking accuracy and time within onboard limited computational resources of UAVs.To meet the tracking precision and real-time requirements,this paper proposes a Siamese dense pixel-level network for UAV object tracking named SiamDPL.Specifically,the Siamese network extracts features of the search region and the template region through a parameter-shared backbone network,then performs correlationmatching to obtain the candidate regionwith high similarity.To improve the matching effect of template and search features,this paper designs a dense pixel-level feature fusion module to enhance the matching ability by pixel-wise correlation and enrich the feature diversity by dense connection.An attention module composed of self-attention and channel attention is introduced to learn global context information and selectively emphasize the target feature region in the spatial and channel dimensions.In addition,a target localization module is designed to improve target location accuracy.Compared with other advanced trackers,experiments on two public benchmarks,which are UAV123@10fps and UAV20L fromthe unmanned air vehicle123(UAV123)dataset,show that SiamDPL can achieve superior performance and low complexity with a running speed of 100.1 fps on NVIDIA TITAN RTX.

关键词： Siamese network UAV object tracking dense pixel-level feature fusion attention module target localization

Time-Modulated Transmissive Programmable Metasurface for Low Sidelobe Beam Scanning

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Research 2022年第4期2022卷 547-555页

作者： xudong Baio Fuli Zhang Li sun Anjie Cao Jin Zhang Chong He Longhai Liu Jianquan Yao Weiren Zhu School of Microelectronics Northwestern Polytechnical UniversityTaicang215400 SuzhouChina School of Physical Science and Technology Northwestern Polytechnical UniversityXian 710072China Shanghai Institute of Satelite Engineering Shanghai 201109China Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China Colege of Precision Instruments and Opto-Electronics Engineering Institute of Laser and OptoelectronicsTianjin UniversityTianjin300072China

Programmable metasurfaces have great potential for the implementation of low-complexity and low-cost phased arrays.Due to the difficulty of multiple-bit phase control,conventional programmable metasurfaces suffer a relatively high sidelobe level(SLL).In this manuscript,a time modulation strategy is introduced in the 1-bit transmissive programmable metasurface for reducing the SLLs of the generated patterns.After the periodic time modulation,harmonics are generated in each reconfigurable unit and the phase of the first-order harmonic can be dynamically controlled by applying different modulation sequences onto the corresponding unit.Through the high-speed modulation of the real-time periodic coding sequences on the metasurface by the programmable bias circuit,the equivalent phase shift accuracy to each metasurface unit can be improved to 6-bit and thus the SLLs of the metasurface could be reduced remarkably.The proposed time-modulated strategy is verified both numerically and experimentally with a transmissive programmable metasurface,which obtains an aperture efficiency over 34%and reduced SLLs of about-2o dB.The proposed design could offer a novel approach of a programmable metasurface framework for radar detection and secure communication applications.

关键词： surface periodic harmonics