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胫骨pilon骨折的常用分型与思考

中华创伤骨科杂志 2021年第7期23卷 553-557页

作者：汤欣娄志远大连医科大学附属第一医院骨科医院 116011

Pilon一词在法语中的意思为杵(pestle),1911年首先被法国放射学家Destot应用于骨科,来比喻胫骨干骺端与距骨的相互作用。轴向压缩暴力导致的胫骨干骺端骨折,骨折线累及关节面负重区,即为胫骨pilon骨折,此命名基于其受伤机制。踝关节顶... 详细信息

Pilon一词在法语中的意思为杵(pestle),1911年首先被法国放射学家Destot应用于骨科,来比喻胫骨干骺端与距骨的相互作用。轴向压缩暴力导致的胫骨干骺端骨折,骨折线累及关节面负重区,即为胫骨pilon骨折,此命名基于其受伤机制。踝关节顶部呈穹窿状,1950年Bonin将这类骨折从解剖学角度称为胫骨plafond骨折。胫骨pilon骨折和胫骨plafond骨折命名角度不同,其内涵不尽相同,但目前在实际使用中并未予以严格区分。

关键词：放射学家胫骨干骺端受伤机制距骨骨折,骨负重区踝关节轴向压缩

Reinforcement learning-based resilience optimization of combat system-of-systems considering protective resource supplementation: From the perspective of continuous interference

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Reinforcement learning-based resilience optimization of comb...

第六届体系工程学术会议—体系工程与高质量发展

作者： LIU Jiahao XU Renjie LI Jichao YANG Kewei lou zhiyuan College of Systems Engineering National University of Defense Technology School of Management Technical University of Munich

As a complex military system composed of multiple interrelated and interdependent subsystems, combat system-of-systems(CSoS) plays an increasingly important role in modern warfare. However, continuous interference usually occurs to affect CSoS's normal services or functions after systems are deployed. Optimizing the resilience of CSoS holds significant value in minimizing service disruption, reducing adverse impact, and enhancing network survivability. From the perspective of continuous interference, we propose a united framework called reinforcement learning-based resilience optimization of CSoS considering protective resource supplementation(ROCSoS). Firstly, we present an index named the CSoS resilience index(CSoSRI) to measure the resilience of CSoS. This index integrates CSoS's structure, performance, performance baseline, as well as resistance and recovery capabilities in continuous interference. Subsequently, a resilience-oriented protection optimization method based on reinforcement learning(RL) is proposed by considering the dynamic nature of supplementation and the coexistence of interference, protection, and recovery. Finally, we conduct extensive simulation experiments on a CSoS case to demonstrate the effectiveness and superiority of the proposed ROCSoS. This study compares the ROCSoS with several baseline methods, revealing its superior performance. The results provide useful insights for guiding and designing the more resilient CSoS.

关键词： combat system-of-systems resilience optimization reinforcement learning protective resource supplement continuous interference

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大数据驱动的运动服饰感性设计系统研究

装饰 2024年第5期 24-28页

作者：沈雷闵雪楼之源江南大学设计学院英国帝国理工学院戴森设计学院

在运动服装新产品开发过程中,掌握产品的预期情感评价对于最大限度地降低开发风险、实现可持续发展至关重要。在信息时代背景下,大数据驱动在设计方法创新中面临新的机会。本文提出了一个从网络数据中提取运动针织服装设计及评价信息的... 详细信息

在运动服装新产品开发过程中,掌握产品的预期情感评价对于最大限度地降低开发风险、实现可持续发展至关重要。在信息时代背景下,大数据驱动在设计方法创新中面临新的机会。本文提出了一个从网络数据中提取运动针织服装设计及评价信息的方法,结合文本挖掘、感性工学、机器学习等科学工具完成设计系统的创新。文章以运动服饰针织护膝为研究对象,为网络数据驱动的运动服装产品设计情感评价和预测提供了一种新的方法,为大数据指导的运动服装产品设计提供了一条新的途径。

关键词：运动服饰数据驱动设计系统创新设计感性工程

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重型柴油机起动工况的颗粒数量排放特性

内燃机学报 2016年第5期34卷 431-437页

作者：谭丕强邹乐华胡志远楼狄明杨蓉同济大学汽车学院上海201804

以一台采用电控高压共轨的重型柴油机为样机,分别研究柴油机在冷机起动工况（冷却水温度为24,℃）和热机起动工况（冷却水温度为80,℃）的颗粒排放特性.结果表明：冷机起动工况下,颗粒数量的粒径分布呈单峰形态,核态颗粒的数量峰值粒径... 详细信息

以一台采用电控高压共轨的重型柴油机为样机,分别研究柴油机在冷机起动工况（冷却水温度为24,℃）和热机起动工况（冷却水温度为80,℃）的颗粒排放特性.结果表明：冷机起动工况下,颗粒数量的粒径分布呈单峰形态,核态颗粒的数量峰值粒径在20~30,nm之间;热机起动工况下,颗粒数量的粒径分布呈双峰形态,核态颗粒和聚集态颗粒的数量峰值粒径分别在15,nm和130,nm附近.颗粒的粒径小于100,nm时,冷机起动的颗粒数量要远大于热机起动.不论是冷机起动还是热机起动工况,瞬时颗粒数量均先上升、后下降并最后趋于相对稳定.前期起动阶段的瞬时颗粒数量均高于怠速稳定阶段;冷机起动工况下,瞬时核态颗粒和聚集态颗粒的数量大都明显高于热机起动工况.前期起动阶段、怠速稳定阶段和整个起动工况的累计核态颗粒数量,在总颗粒数量中都占有绝对支配地位.

关键词：柴油机排放冷机起动热机起动颗粒数量核态颗粒聚集态颗粒

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允许保圆变换的爱因斯坦空间的规范基本形式

杭州大学学报(自然科学版) 1984年第1期 4-13页

作者：娄志渊

本文所论空间的基本形式均限于正定的.用E_n表示n维爱因斯坦空间.下面指标取值范围,通篇应用: α,β,γ,δ,…,=1,2,…n; h,i,j,k,…,=2,3,…,n. 白正国在〔1〕中已给出允许保圆变换的E_n的基本形式的统一形式.本文目的是更进一步地给... 详细信息

本文所论空间的基本形式均限于正定的.用E_n表示n维爱因斯坦空间.下面指标取值范围,通篇应用: α,β,γ,δ,…,=1,2,…n; h,i,j,k,…,=2,3,…,n. 白正国在〔1〕中已给出允许保圆变换的E_n的基本形式的统一形式.本文目的是更进一步地给出这个形式的各个不同特征的具体形式.本文的n都限制为n〉3.

关键词：线素向量场矢量场常曲率空间中取

基于百太瓦级激光系统驱动的高能量13 nm波段高次谐波产生

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光学学报 2024年第2期44卷 221-228页

作者：高记星娄智远杨帆杨晓骏许毅冷雨欣郑颖辉曾志男李儒新中国科学院上海光学精密机械研究所强场激光物理国家重点实验室上海201800 中国科学院大学材料科学与光电工程中心北京100049 张江实验室上海201210

利用百太瓦级激光系统在氖气(Ne)中得到基于高次谐波产生的极紫外脉冲。通过松聚焦结构在13 nm波段产生单级次单脉冲能量为13.5 nJ(13.1 nm波长)和11.1 nJ(13.5 nm波长)的高次谐波辐射,转换效率为3.6×10^(-7)和3.0×10^(-7),谐波发散... 详细信息

利用百太瓦级激光系统在氖气(Ne)中得到基于高次谐波产生的极紫外脉冲。通过松聚焦结构在13 nm波段产生单级次单脉冲能量为13.5 nJ(13.1 nm波长)和11.1 nJ(13.5 nm波长)的高次谐波辐射,转换效率为3.6×10^(-7)和3.0×10^(-7),谐波发散角的半高全宽为0.32 mrad和0.33 mrad。对含时薛定谔方程进行数值求解,得到单原子偶极发射谱,结合麦克斯韦方程组模拟传播效应,同时考虑气体对谐波的吸收效应,理论模拟得到的信号强度随气压和光强的变化趋势与实验结果基本符合。实现相位匹配的谐波光束质量很好,纵向空间分布为高斯型。结合相位匹配条件和空间分布的分析得到了目前激光参数下的最优相位匹配条件。这种基于高次谐波机制的高能量相干极紫外光源在作为自由电子激光的种子光源以及超快非线性实验和半导体工业检测等方面具有广阔的应用前景。

关键词：极紫外高次谐波相位匹配空间分布

Effect of catalyst diesel particulate filter aging and catalyst loadings on particulate emission characteristics from a diesel vehicle

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Journal of Environmental Sciences 2024年第2期136卷 35-44页

作者： Yunhua Zhang Diming lou Piqiang Tan zhiyuan Hu Liang Fang School of Automotive Studies Tongji UniversityShanghai 201804China

In this study,the effect of new and used catalyzed diesel particulate filter(CDPF)with different catalyst loadings on the particulate emissions including the particle mass(PM),particle number(PN),particle size distribution(PSD)and geometric mean diameter(GMD)from a diesel vehicle were investigated based on a heavy chassis *** showed that more than 97.9%of the PN and 95.4%of the PM were reduced by the CDPF,and the reduction efficiency was enhanced by the catalyst *** using the CDPF,the PSD transformed from bimodal to trimodal with the peak shifting towards smaller particle size,more nucleation mode particles were reduced compared with accumulation mode ones,but the reduction effect on the accumulation mode particles was more significantly influenced by the catalyst ***,the CDPF increased the accumulation mode particles proportion,producing a larger *** the used CDPF,its reduction effect on the particulate emissions enhanced,especially for the PM in accumulation *** PSD returned to bimodal,but the peak at accumulation mode began to be higher than that at nucleation mode,illustrating that more nucleation mode particles was *** aging of the CDPF resulted in greater effect on the PN-based PSD than that of PM-based PSD,but the effect of catalyst loading on the PN and PM emission factors was *** used CDPF further increased the GMD,and the effect of catalyst loading on the GMD was strengthened,a higher catalyst loading led to a reduction in the GMD.

关键词： Catalyzed diesel particulate filter (CDPF) Catalyst loading Aging Particle Particle size distribution Geometric mean diameter

Effect of catalyzed diesel particulate filter and its catalyst loading on emission characteristics of a non-road diesel engine

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Journal of Environmental Sciences 2023年第4期126卷 794-805页

作者： Yunhua Zhang Diming lou Piqiang Tan zhiyuan Hu Liang Fang School of Automotive studies Tongji UniversityShanghai 201804China

In this study, the effects of a diesel oxidation catalyst(DOC) coupled with a catalyzed diesel particulate filter(CDPF) with different catalyst loadings on the power, fuel consumption,gaseous and particulate emissions from a non-road diesel engine were investigated. Results showed that the after-treatment had a negligible effect on the power and fuel *** reduction effect of the DOC on the CO and hydrocarbon(HC) increased with the engine load. Further reductions occurred coupling with the CDPF. Increasing the catalyst loading resulted in a more significant reduction in the HC emissions than CO emissions. The DOC could increase the NO_(2)proportion to 37.9%, and more NO_(2)was produced when coupled with the CDPF below 250℃;above 250℃, more NO_(2)was consumed. The after-treatment could reduce more than 99% of the particle number(PN) and 98% of the particle mass(PM).Further reductions in the PN and PM occurred with a higher CDPF catalyst loading. The DOC had a better reduction effect on the nucleation particles than the accumulation ones, but the trend reversed with the CDPF. The DOC shifted the particle size distribution(PSD) to larger particles with an accumulation particle proportion increasing from 13% to 20%, and the geometric mean diameter(GMD) increased from 18.2 to 26.0 nm. The trend reversed with the CDPF and the accumulation particle proportion declined to less than 10%. A lower catalyst loading on the CDPF led to a higher proportion of nucleation particles and a smaller GMD.

关键词： Catalyzed diesel particulate filter Catalyst loading Emissions Particle size distribution Geometric mean diameter

Selective catalytic reduction failure of low NH_(3)-NO_(x) ratio

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Chinese Journal of Chemical Engineering 2021年第4期34卷 231-240页

作者： Piqiang Tan Xiaoyu Li Shiyan Wang zhiyuan Hu Diming lou School of Automobile Studies Tongji UniversityShanghai 201804China

An insufficient amount of NH_(3) (ammonia)will reduce the conversion efficiency of NO_(x),which may lead to excess NO_(x) emissions,resulting in NH3SCR *** this article,SCR failure caused by a low NH_(3)NO_(x) ratio is studied systematically by *** main reasons for a low NH_(3)NO_(x) ratio in SCR include insufficient urea injection,hydrothermal aging of catalysts and urea *** was found from an insufficient urea injection experiment that with the increase of NH_(3)NO_(x) ratio,the NO_(x) conversion efficiency of the SCR system increased,but the ammonia leakage also *** main influencing factors of NO_(x) conversion efficiency are different under different NH3NOx ratios.A flow reactor system was used in the catalyst hydrothermal aging experiment to investigate the effect of hydrothermal aging on catalyst *** a 24 h hydrothermal aging experiment at 800℃,the NO_(x) conversion efficiency of the copperbased zeolite catalysts decreased significantly at the boundary of medium and low temperature *** the NO_(2)-NO_(x) ratio in the mixture had a significant effect on the catalytic *** coupled to Fourier transform infrared spectroscopy(TGFTIR)was used to analyze the composition of urea deposits in a urea deposits analysis *** was found that the main components of urea deposits were urea and isocyanic acid(HNCO).Preventing HNCO polymerization,especially the formation of CYA,can decrease the formation of urea deposits.

关键词： SCR Low NH_(3)-NO_(x)ratio Purification Hydrothermal Urea crystallization