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近场爆炸下波纹双钢板混凝土组合墙板的损伤破坏及抗爆性能

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高压物理学报 2024年第1期38卷 85-101页

作者：赵春风张利李晓杰合肥工业大学土木与水利工程学院安徽合肥230000 大连理工大学工业装备结构分析国家重点实验室辽宁大连116024

相对于传统的钢筋混凝土墙板和平面双钢板-混凝土组合墙板(profiled double-skin composite wall,PDSCW),波纹双钢板-混凝土组合墙板(concrete-infilled double steel corrugatedplate wall,CDSCW)具有更高的轴向抗压承载力、更大的侧向抗弯刚度以及良好的抗冲击和抗震性能,在船舶和军事领域有广阔的应用前景。制作2种CDSCW试件,通过近场爆炸试验对比分析了2种试件的损伤模式及动态响应;采用ANSYS/LS-DYNA软件建立了CDSCW和PDSCW的有限元模型,研究了近场爆炸下2种混凝土组合墙板的损伤机理和爆炸响应,并与试验结果进行对比分析;分析了混凝土厚度、钢板厚度、药量对CDSCW抗爆性能的影响。结果表明:近场爆炸作用下,相较于PDSCW,相同混凝土方量和尺寸(长、宽)的CDSCW具有更大的抗弯刚度、更强的抗变形能力以及更优的抗爆性能;增加波纹深度能有效提高CDSCW的抗爆性能,可为抗爆构件设计和相关工程研究提供参考。

关键词：近场爆炸波纹双钢板混凝土组合墙板损伤模式动态响应抗爆性能

High-precision orbit prediction and error control techniques for COMPASS navigation satellite

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Chinese Science Bulletin 2014年第23期59卷 2841-2849页

作者： xiaojie li Jianhua Zhou Rui Guo Beijing Satellite Navigation Center

A new satellite orbit prediction method based on artificial neural network(ANN)model is proposed to improve the precision of orbit *** order to avoid the difficulty of amending the dynamical model,it is attempted to use ANN model to learn the variation of orbit prediction error,and then the prediction result of ANN model is used to compensate the predicted orbit based on dynamic model to form a final predicted *** experiment results showed that the orbit prediction error based on ANN model was less than that based on dynamical model,and the improvement effects for different satellites and different time were *** maximum rates of improvement of predicting 8,15,30 d were respectively 80%,77.77%,85%.The orbit prediction error control technique based on the method of back overlap arc compare was brought forward to avoid the risk that the precision of predicted orbit is even worse after it is compensated by ANN *** phenomena of failure were basically eliminated based on this technique,and the rate of failure was reduced from 30%to 5%.This technique could ensure that the engineering application of ANN model could come true.

关键词：北斗导航卫星差错控制技术轨道预报高精度人工神经网络模型动力学模型轨道预测神经网络学习

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氟化钠吸附和解吸氟化氢工艺响应面优化

化学工程 2024年第6期52卷 33-39页

作者：李權丁勇罗艳高超吴俊李晓杰王真文刘彦岑陈文秀李金泽四川红华实业有限公司四川乐山614200

NaF是一种具有高选择性、高吸附容量的HF吸附剂,被广泛应用于F-Gas(含氟电子气体)纯化工艺中。以温度、压力、流量作为研究因素,采用响应面法中BBD(Box-Behnken设计)对NaF吸附和解吸HF分别进行工艺参数优化研究。建立影响HF吸附量和解... 详细信息

NaF是一种具有高选择性、高吸附容量的HF吸附剂,被广泛应用于F-Gas(含氟电子气体)纯化工艺中。以温度、压力、流量作为研究因素,采用响应面法中BBD(Box-Behnken设计)对NaF吸附和解吸HF分别进行工艺参数优化研究。建立影响HF吸附量和解吸量的数学模型,并详细探究影响HF吸附和解吸工艺因素的显著性,以及因素交互作用对HF吸附和解吸的影响规律。结果表明:影响HF吸附和解吸的主要因素分别为流量和温度,当吸附温度为59℃,吸附压力为0.4 MPa,气体流量为345 mL/min时,HF吸附量最大达到512 mg/g;当解吸温度为348℃,解吸压力为0.23 MPa,气体流量为400 mL/min时,HF解吸量最大为478 mg/g。为含氟电子气体纯化工艺的参数优化提供重要参考。

关键词：氟化钠氟化氢响应面法吸附与解吸工艺优化

Structural engineering design of carbon dots for lubrication

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Chinese Chemical Letters 2021年第9期32卷 2693-2714页

作者： Chuang He Shuang E Honghao Yan xiaojie li State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Research Center for Analytical Sciences Northeastern UniversityShenyang 110819China

Carbon dots(CDs)have opened up a new field of carbon nanomaterials and successively attracted increasing attention since their discovery in *** to their ultrasmall size,tunable surface functional groups,excellent dispersibility,attractive stability,low toxicity,environmental friendliness,facile synthesis and low-cost precursors,CDs have been developed as green and promising frictionreducing and anti-wear materials in lubrication science,applied to energy conservation and extension of mechanical service life in recent ***,there are few reviews focusing on the application of CDs in the important field of *** this review,we comprehensively summarize the development of CDs in lubrication for the first ***,three strategies for structural engineering design of CDs to improve their tribological characteristics are fully analyzed,in terms of size and shape control,surface modification and heteroatom ***,the advance in lubrication application of CDs,including CDs as additives for lubricants,greases,gel and magnetorheological fluids as well as CDs as lubricating coatings,is systematically ***,the lubricating mechanisms of CDs as additives are introduced in ***,the remaining major challenges and opportunities for CDs in lubrication field are discussed and outlined.

关键词： Carbon dots Lubrication Tribological characteristics Lubricating mechanism

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智慧中医服务新模式的探索与思考

中国数字医学 2024年第7期19卷 12-16,28页

作者：钟臻李晓洁何萍上海申康医院发展中心医联中心上海200041 上海申康医院医联工程与信息化部上海200041 上海中医药大学附属市中医医院

目的:通过人工智能技术与中医医疗场景的深度融合,探索推动中医医疗模式创新与变革,满足患者中医医疗舒适化、数字化和智慧化需求。方法:基于中医辨证诊断和预防保健理念,运用大数据、物联网、5G等数字化技术,借助中医数据采集智能移动... 详细信息

目的:通过人工智能技术与中医医疗场景的深度融合,探索推动中医医疗模式创新与变革,满足患者中医医疗舒适化、数字化和智慧化需求。方法:基于中医辨证诊断和预防保健理念,运用大数据、物联网、5G等数字化技术,借助中医数据采集智能移动终端平台,构建“创新型中医医疗场景”,实现线上中医辨证诊治、中医诊断分型、“一站式”中医出入院准备、中医健康管理及中医云客服,打造智慧中医服务新模式。结果:相较于更依赖检验检查的西医诊疗,融合了望诊、闻诊、问诊、切诊四诊合参的创新型中医医疗,在传承名老中医经验的基础上,更加突出个性化服务,借助物联网开展远程会诊、定期随访等远程医疗服务,实现患者就医全流程管理,提升了患者就医体验感和获得感。结论:通过算法、算力和中医医疗应用场景的有机结合,推动了中医医疗服务行业的智能化和个性化发展,为中医医疗模式的革新与进步提供了新思路和新模式。

关键词：现代中医数字化技术中医五行医疗场景智慧服务

Degradation of dissolved organic matter in effluent of municipal wastewater plant by a combined tidal and subsurface flow constructed wetland

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Journal of Environmental Sciences 2021年第8期33卷 171-181页

作者： Chunjian Lyu Ruixia liu xiaojie li Yonghui Song Hongjie Gao Basin Research Center for Water Pollution Control Chinese Research Academy of Environmental SciencesBeijing 100012China College of Water Sciences Beijing Normal UniversityBeijing 100875China

Dissolved organic matter(DOM)is an important constituent of wastewater treatment plant(WWTP)effluent.A novel combined tidal and subsurface flow constructed wetland(TF-SSFCW)of 90 L was constructed for a ten-month trial of advanced treatment of the WWTP *** emission matrix(EEM)fluorescence spectroscopy,parallel factor(PARAFAC)analysis and a two end-member mixing model were employed to characterize the composition and removal process of the effluent DOM(EfOM)from the *** results showed that the TF-SSF-CW performed an efficient EfOM removal with dissolved organic carbon(DOC)removal rate of 88%and dissolved organic nitrogen(DON)removal rate of 91%.Further analysis demonstrated that the EfOM consisted mainly of two protein moieties and two humic-like groups;protein moieties(76%)constituted the main content of EfOM in raw water and humic-like groups(57%)became the dominating contributor after *** EfOM from the WWTP was mainly of aquatic bacterial origin and evolved to a higher proportion of terrigenous origin with higher humification in the TF-SSF-CW effluent.A common controlling treatment-related factor for determining the concentrations of the same kind of substances(protein groups or humic-like groups)was revealed to exist,and the ratio of removal rates between the same substances in treatment was *** study demonstrates that the TF-SSF-CW can be a novel and effective treatment method for the EfOM from WWTPs,and is helpful for understanding of the character of EfOM in wetland treatment.

关键词： Constructed wetland Effluent organic matter Excitation emission matrices PARAFAC analysis

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“割裂化”对我国战略性矿产资源安全的影响

中国国土资源经济 2024年第3期37卷 4-10,17页

作者：高勇李晓杰左更中国五矿集团有限公司北京100010

席卷全球的新冠疫情及近年来愈演愈烈的大国博弈,使得全球经济布局向“割裂化”发展的趋势十分明显,逼迫全球经济“重启”,对中国战略性金属矿产行业产生巨大的影响。未来较长一段时间内,我国战略性金属矿产行业发展仍将围绕工业基础品... 详细信息

席卷全球的新冠疫情及近年来愈演愈烈的大国博弈,使得全球经济布局向“割裂化”发展的趋势十分明显,逼迫全球经济“重启”,对中国战略性金属矿产行业产生巨大的影响。未来较长一段时间内,我国战略性金属矿产行业发展仍将围绕工业基础品种和新能源转型金属品种展开。但是自然禀赋的原因造成我国仅依靠国内资源根本无法满足所需,“一带一路”沿线国家的矿业资源仍将是我国关键矿产资源保障的主要来源。面对当前更趋复杂严峻的外部环境,必须大力推进“一带一路”共建国家间合作;积极倡导ESG行动工程,在大国外交框架下树立中国形象;大力做好国内稳经济、稳市场、稳金融工作;在关键商品上实施差异化措施,针对性地制定发展思路和举措;大力压减国内低效产能,提高行业关键技术和再生金属回收与利用水平,增强行业企业竞争能力;建立国家重要物资“安全回国”通道,全面提升战略性矿产资源保障能力和资源安全。

关键词：经济重启割裂化发展战略性金属矿产一带一路资源安全

Orbit determination and prediction for Beidou GEO satellites at the time of the spring/autumn equinox

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Science China(Physics,Mechanics & Astronomy) 2015年第8期58卷 86-94页

作者： li xiaojie ZHOU JianHua HU XiaoGong liU li GUO Rui ZHOU ShanShi Beijing Satellite Navigation Center Shanghai Key Laboratory of Space Navigation and Position Techniques Shanghai Astronomical Observatory Chinese Academy of Sciences

Geostationary(GEO) satellites form an indispensable component of the constellation of Beidou navigation system(BDS). The ephemerides, or predicted orbits of these GEO satellites(GEOs), are broadcast to positioning, navigation, and timing users. User equivalent ranging error(UERE) based on broadcast message is better than 1.5 m(root formal errors: RMS) for GEO satellites. However, monitoring of UERE indicates that the orbital prediction precision is significantly degraded when the Sun is close to the Earth's equatorial plane(or near spring or autumn Equinox). Error source analysis shows that the complicated solar radiation pressure on satellite buses and the simple box-wing model maybe the major contributor to the deterioration of orbital precision. With the aid of BDS' two-way frequency and time transfer between the GEOs and Beidou time(BDT, that is maintained at the master control station), we propose a new orbit determination strategy, namely three-step approach of the multi-satellite precise orbit determination(MPOD). Pseudo-range(carrier phase) data are transformed to geometric range(biased geometric range) data without clock offsets; and reasonable empirical acceleration parameters are estimated along with orbital elements to account for the error in solar radiation pressure modeling. Experiments with Beidou data show that using the proposed approach, the GEOs' UERE when near the autumn Equinox of 2012 can be improved to 1.3 m from 2.5 m(RMS), and the probability of user equivalent range error(UERE)<2.0 m can be improved from 50% to above 85%.

关键词： Beidou system (BDS) Beidou time (BDT) geostationary (GEO) satellite spring equinox/autumn equinox solar radia-tion pressure time synchronization user equivalent ranging error

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基于多要素的短临降水预报及可解释性分析

计算机应用研究 2024年第9期41卷 2773-2780页

作者：陈龙彭静胡雪飞黄占鳌李孝杰成都信息工程大学计算机学院成都610225

当前的短临降水预报方法大多是基于雷达回波外推,没有充分考虑其他气象要素对降水生消演变的密切影响,从而限制了其预报的准确性。为解决此问题,基于风云四号B星数据,制作了包含四种背景气象要素、以定量降水估计为预报对象的短时临近... 详细信息

当前的短临降水预报方法大多是基于雷达回波外推,没有充分考虑其他气象要素对降水生消演变的密切影响,从而限制了其预报的准确性。为解决此问题,基于风云四号B星数据,制作了包含四种背景气象要素、以定量降水估计为预报对象的短时临近降水预报数据集,提出了短临降水预报模型——MFPNM。以TransUNet为骨干,设计了并行双编码器分别提取预报对象和背景气象数据的高维时空特征;构造了内容编码模块将背景数据的空间特征作为预报对象高维特征向量的可学习位置编码;以已有的Transformer模块构建序列数据高维特征间的全局关系,以实现更准确的序列预测。MFPNM在风云-4B数据集和开源数据集上达到了最优水平,采用的指标包括临界成功指数、虚警率、均方根误差和结构相似性等。同时通过SHAP(shapley additive explanations)技术对模型进行了可解释性分析。实验结果及可解释性分析表明,该模型具有更好的预报准确度及可靠性。

关键词：短时临近降水预报气象卫星数据融合

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