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混合交通流环境下基于改进强化学习的可变限速控制策略

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交通运输系统工程与信息 2023年第3期23卷 110-122页

作者：韩磊张轮郭为安同济大学道路与交通工程教育部重点实验室上海201804 同济大学电子与信息工程学院上海201804 同济大学中德工程学院上海201804

现有的可变限速(VSL)控制策略灵活性较差,响应速度较慢,对驾驶人遵从度和交通流状态预测模型的依赖性较高,且单纯依靠可变限速标志(VMS)向驾驶人发布限速值,难以在智能网联车辆(CAVs)与人工驾驶车辆(HDVs)混行的交通环境中实现较好的控... 详细信息

现有的可变限速(VSL)控制策略灵活性较差,响应速度较慢,对驾驶人遵从度和交通流状态预测模型的依赖性较高,且单纯依靠可变限速标志(VMS)向驾驶人发布限速值,难以在智能网联车辆(CAVs)与人工驾驶车辆(HDVs)混行的交通环境中实现较好的控制效果。对此,结合深度强化学习无需建立交通流预测模型,能自动适应复杂环境,以及CAVs可控性的优势,提出一种混合交通流环境下基于改进竞争双深度Q网络(IPD3QN)的VSL控制策略,即IPD3QN-VSL。首先,将优先经验回放机制引入深度强化学习的竞争双深度Q网络(D3QN)框架中,提升网络的收敛速度和参数更新效率;并提出一种新的自适应ε-贪婪算法克服深度强化学习过程中探索与利用难以平衡的问题,实现探索效率和稳定性的提高。其次,以最小化路段内车辆总出行时间(TTS)为控制目标,将实时交通数据和上个控制周期内的限速值作为IPD3QN算法的输入,构造奖励函数引导算法输出VSL控制区域内执行的动态限速值。该策略通过基础设施到车辆通信(I2V)向CAVs发布限速信息,HDVs则根据VMS上公布的限速值以及周围CAVs的行为变化做出决策。最后,在不同条件下验证IPD3QN-VSL控制策略的有效性,并与无控制情况、反馈式VSL控制和D3QN-VSL控制进行控制效果上的优劣对比。结果表明:在30%渗透率下,所提策略即可发挥显著控制性能,在稳定和波动交通需求情境中均能有效提升瓶颈区域的通行效率,缩小交通拥堵时空范围,与次优的D3QN-VSL控制相比,两种情境中的TTS分别改善了14.46%和10.36%。

关键词：智能交通可变限速控制改进竞争双深度Q网络混合交通流智能网联车辆深度强化学习

The vascular endothelial growth factor expression and vascular regeneration in infarcted myocardium by skeletal muscle satellite cells

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Chinese Medical Journal 2006年第2期119卷 117-121页

作者： XIA Jia-hong XIE Ai-ni zhang Kai-lun XU Lei ZHENG Xiang-yang Department of Cardiovascular Surgery Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China

Background Myocardial infarction results in tissue necrosis, leading to cell loss and ultimately to cardiac failure. Implantation of skeletal muscle satellite cells into the scar area may compensate for the cell loss and provides a new strategy for infarct therapy. Vascular endothelial growth factor （VEGF） is a promising reagent for inducing myocardial angiogenesis. Skeletal myoblast transplantation has been shown to improve cardiac function in chronic heart failure models by regenerating muscle. We hypothesized that VEGF expression and vascular regeneration increased in infarcted myocardium by skeletal muscle satellite cells, which can promote vascular producing and improve survival environment in infarcted myocardium. Methods The skeletal muscle satellite cells were implanted into the infarcted myocardium in a model through ligated left anterior artery in Louis Inbrad Strain rat. Specimens were got for identifying the expression of VEGF and the density of vascular by immunochemical method at two weeks after implantation. Results The proliferation and differentiation of the skeletal muscle satellite cell was very well. The expression of VEGF was higher in the implanted group （146.83±2.49） than that in the control group （134.26±6.84）（P〈0.05）. The vascular density in the implanted group （13,00± 1.51） was also higher than that in the control （10.68 ± 1.79）（P〈0.05）. Conclusion The implanted satellite cell could excrete growth factor that would induce angiogenesis and improve cell survival environment in infarcted myocardium.

关键词： skeletal muscle satellite cell vascular endothelial growth factor vascular infarcted myocardium

Some New Water-Soluble Phosphines with the Involvement of the Trivalent Rare Earth Ion

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 86-91页

作者： Chen Xinlan,Lei Peng, zhang Let, Pei Hong, zhang lun(Department of Chemistry, Wuhan University, Wuhan 430072,China)(State Key Laboratery for Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 7 Department of Chemistry Wuhan University Wuhan China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Science Lanzhou China

The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPPTS?Na3 and oxides of rare earth. The chemical composition of TPPTS?Ln was determined by elemental analysis and ICP-AES. IR, Raman showed that the sulfonate group in the complexes was a tridentate ligand.31P NMR, TG-DTA, molar conductivity and the fluorescence of these complexes were also recorded and discussed.

关键词： rare earth complex water soluble phosphine synthesis and properties

Magnetic resonance imaging of knees:a novel approach to predict recombinant human growth hormone therapy response in short-stature children in late puberty

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World Journal of Pediatrics 2024年第7期20卷 723-734页

作者： Xi Bai Zhi‑Bo Zhou Xiao‑Yuan Guo Yi‑Ling He Yue‑lun zhang Feng‑Dan Wang Feng Feng Hong‑Bo Yang Shi Chen Feng‑Ying Gong Hui‑Juan Zhu Hui Pan Department of Endocrinology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongChina Key Laboratory of Endocrinology of National Health Commission Department of EndocrinologyState Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Radiology Peking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijingChina

Background There is no appropriate tool to predict recombinant human growth hormone(rhGH)response before therapy initiation in short-stature children in late *** current study aimed to explore the associations between magnetic resonance imaging(MRI)stages of the knee growth plates and rhGH response in short-stature children in late *** In this prospective cohort study,short-stature children in late puberty were treated with rhGH and followed up for 6 *** proposed a novel knee MRI staging system according to the growth plate states of distal femurs or proximal tibias and divided the participants into three groups:unclosed growth plate group,marginally closed growth plate group,and nearly closed growth plate *** primary outcomes were height gain and growth velocity(GV),which were assessed three months *** Fifty participants were enrolled,including 23 boys and 27 *** and height gain after 6 months of rhGH therapy decreased successively in the three groups with an increased degree of growth plate fusion,especially when grouped by proximal tibias(GV_(1-3 mon)from 9.38 to 6.08 to 4.56 cm/year,GV_(4-6 mon)from 6.75 to 4.92 to 3.25 cm/year,and height gain from 4.03 to 2.75 to 1.95 cm,all P<0.001).Moreover,the MRI stages of growth plates independently served as a significant variable for GV and height gain after therapy,especially when grouped by proximal tibias(all P<0.01).Conclusion The MRI staging method is expected to be an effective tool for predicting rhGH response before therapy initiation in short-stature children in late puberty.

关键词： Growth hormone Growth velocity Late puberty Magnetic resonance imaging Short stature

PITD3-based Autonomous Evasion Decision-making Method for Aircraft

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PITD3-based Autonomous Evasion Decision-making Method for Ai...