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黔北地区下寒武统牛蹄塘组泥岩沉积环境及页岩气勘探潜力

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沉积与特提斯地质 2024年第2期44卷 267-277页

作者：何洪茜肖加飞杨海英兰青黄明亮中国科学院地球化学研究所矿床地球化学国家重点实验室贵州贵阳550081 中国科学院大学北京100049

寒武系下统牛蹄塘组是中国南方海相碳质页岩赋存的主要层位之一,在贵州北部、中部及东部广泛分布,层位稳定。牛蹄塘组以黑色炭质泥岩为主,岩层多为薄层状,具水平层理,其组分主要为黏土矿物、石英及少量的碳质组分和黄铁矿。与澳大利亚... 详细信息

寒武系下统牛蹄塘组是中国南方海相碳质页岩赋存的主要层位之一,在贵州北部、中部及东部广泛分布,层位稳定。牛蹄塘组以黑色炭质泥岩为主,岩层多为薄层状,具水平层理,其组分主要为黏土矿物、石英及少量的碳质组分和黄铁矿。与澳大利亚后太古代页岩(PAAS)平均值相比,泥岩V、Mo、U含量较高,而Co、Cu、Zn和Th含量较低。V/Cr、Ni/Co、U/Th、V/(V+Ni)的元素比值以及AU含量表明,牛蹄塘组黑色泥岩沉积环境呈缺氧还原状态。样品(La/Yb)N值明显大于1,轻、重稀土元素分异程度较大,指示沉积速率较低。有机质丰度较高,有机质成熟度为高—过成熟阶段,脆性矿物含量较高,有效厚度约为30~100 m。综上,黔北牛蹄塘组黑色泥岩存在形成页岩气藏的较好物质条件,具有良好的页岩气勘探潜力。

关键词：牛蹄塘组页岩气沉积环境勘探潜力黔北

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新疆西瓜甜瓜产业发展现状及对策建议

中国瓜菜 2024年第6期37卷 195-201页

作者：毛亮周成松潘卫萍张彩颖黄明亮肖瑶张以和吐鲁番市农业技术推广中心新疆吐鲁番市838000

通过对新疆西瓜甜瓜种植面积及生产总量、种植区域分布、种植品种、栽培模式、机械化生产、品牌发展、深加工等方面深入调查研究,了解和掌握了新疆西瓜甜瓜产业发展的现状,分析了新疆西瓜甜瓜产业在品种资源、种植区域和产销、栽培技术... 详细信息

通过对新疆西瓜甜瓜种植面积及生产总量、种植区域分布、种植品种、栽培模式、机械化生产、品牌发展、深加工等方面深入调查研究,了解和掌握了新疆西瓜甜瓜产业发展的现状,分析了新疆西瓜甜瓜产业在品种资源、种植区域和产销、栽培技术、生产成本、生产经营、品牌建设、深加工等方面所面临的问题。最后,从加快种业发展、优化种植区域布局、依托科技创新、转变经营模式、加强品牌建设、延长产业链等方面提出了对策和合理化建议。

关键词：西瓜甜瓜新疆发展现状对策建议

Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： You Zhao Xing He mingliang Zhou Tingwen huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence *** previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization *** this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual *** satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence *** only requires assuming convexity of the objective *** validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.

Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network

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International Journal of Mining Science and Technology 2024年第3期34卷 323-337页

作者： Hongwei huang Chen Wu mingliang Zhou Jiayao Chen Tianze Han Le Zhang Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Qingdao Guoxin Second Jiaozhou Bay Subsea Tunnel Co. Ltd.Qingdao 266071China

Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel *** tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative ***,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality *** this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak *** site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is *** the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete *** utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality.

关键词： Rock mass quality Tunnel faces Incomplete multi-source dataset Improved Swin Transformer Bayesian networks

Improved damage tolerance and oxidation resistance of (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–SiC by introducing chopped carbon fibers

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Journal of Advanced Ceramics 2024年第1期13卷 101-112页

作者： Feilong huang Hailong Wang Cheng Fang mingliang Li Gang Shao Jinpeng Zhu Yanchun Zhou School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

High-entropy diborides(HEBs)are considered as promising high-temperature structure materials owing to their high melting point and excellent thermal ***,the intrinsic brittleness is the main obstacle that seriously limits their practical *** overcome with this obstacle,carbon fibers(Cf)with outstanding mechanical properties are used in the present work as a first attempt to improve the damage tolerance of *** as-prepared C_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–SiC composite(C_(f)/HEB–SiC)shows high relative density(97.9%)and good mechanical properties with flexural strength of 411±3 MPa and fracture toughness of 6.15±0.11 MPa·m^(1/2).More importantly,the damage tolerance parameter(Dt)has increased from 0.10 m^(1/2) for HEB–SiC to 0.29 m^(1/2) for C_(f)/HEB–*** microstructural analysis and Vickers indentation of the composite,the toughening mechanisms are *** carbon fibers coated with carbon coatings demonstrate unique capacity for prolonging the crack propagation path,which promotes the reliability of the composite ***,the C_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–SiC composite also exhibits good static oxidation resistance in the temperature range of 1100–1500℃in air due to the formation of the protective oxide layer constituting of multicomponent oxides(Zr)HfTiO4 and(Zr)Hf_(6)Ta_(2)O_(17) embedded in a continuous SiO_(2) *** results are promising,and this primary work can be used as a reference to the synthesis of C_(f)/HEBs for thermal protection materials under hightemperature serving conditions.

关键词： high-entropy ceramics carbon fibers(Cf) toughening mechanisms oxidation resistance

老年缺血性脑卒中患者急性期发生脑卒中后疲劳的影响因素及风险预测模型

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广西医学 2024年第5期46卷 687-694页

作者：杨金盘马秋平张佳琳刘裕君黄明亮张杨广西中医药大学护理学院广西南宁市530200 广西中医药大学第一附属医院脑病科广西南宁市530023

目的分析老年缺血性脑卒中患者急性期发生脑卒中后疲劳(PSF)的影响因素,并基于随机森林模型和Logistic回归模型构建风险预测模型。方法选取2家医院的老年缺血性脑卒中患者分别作为训练集(304例)、验证集(102例)。收集患者的一般资料、... 详细信息

目的分析老年缺血性脑卒中患者急性期发生脑卒中后疲劳(PSF)的影响因素,并基于随机森林模型和Logistic回归模型构建风险预测模型。方法选取2家医院的老年缺血性脑卒中患者分别作为训练集(304例)、验证集(102例)。收集患者的一般资料、入院时血清学指标检测结果,并采用疲劳严重程度量表(FSS)对患者进行疲劳评估。在训练集中进行单因素分析,将有统计学意义的血清学指标纳入Lasso回归模型筛选预测变量,再分别使用随机森林模型和Logistic回归模型构建老年缺血性脑卒中患者急性期发生PSF的风险预测模型。利用验证集数据,通过受试者工作特征曲线、校准曲线、Hosmer⁃Lemeshow拟合优度检验、决策曲线分析评价两个模型的预测性能。结果最终筛选出5个具有非零系数的预测变量,分别为C反应蛋白(CRP)、同型半胱氨酸(Hcy)、总胆固醇、空腹血糖、胱抑素C。随机森林模型依据基尼指数减少平均值对预测变量进行重要性排序依次为CRP、Hcy、总胆固醇、空腹血糖、胱抑素C。Logistic回归模型显示,空腹血糖、总胆固醇、CRP、胱抑素C及Hcy水平升高可增加老年缺血性脑卒中患者急性期发生PSF的风险。外部验证结果显示,随机森林模型和Logistic回归模型的曲线下面积、准确度、灵敏度、特异度、阳性预测值、阴性预测值分别为0.905和0.885、0.814和0.755、0.830和0.855、0.800和0.787、0.780和0.826、0.846和0.696。两种模型校准度均良好,在阈值0.08~0.86范围内具有较高的净收益率。结论空腹血糖、总胆固醇、CRP、胱抑素C、Hcy水平与老年缺血性脑卒中患者急性期PSF的发生密切相关。基于上述血清学指标构建的随机森林模型和Logistic回归模型在预测老年缺血性脑卒中患者急性期发生PSF方面均具有较好的价值,其中随机森林模型的预测效能相对较好,而Logistic回归模型能直观解释变量对PSF发生风险的影响程度,可以作为随机森林模型的补充。

关键词：缺血性脑卒中卒中后疲劳影响因素预测模型随机森林模型 Logistic回归模型老年人

Cluster-Delay Consensus for the Second-Order Nonlinear Multi-Agent Systems with Random Noises

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Cluster-Delay Consensus for the Second-Order Nonlinear Multi...

倒装芯片无铅凸点β-Sn晶粒取向与电迁移交互作用

第三十九届中国控制会议

作者： Jun huang mingliang huang Department of Mathematics Beijing Jiaotong University Department of Genetics Evolution and Environment University College London

Cluster-delay consensus in a noisy environment has been investigated for the second-order nonlinear multi-agent systems, which consist of a leader and several followers. A novel protocol with white noise is proposed for the followers of different groups tracking their leader gradually with distinct time delays, i.e., followers are divided into several groups according to the time-delays with the leader and each group approaches its own equilibrium state almost surely and exponentially. Based on the Lyapunov’s method for stability, matrix theory and stochastic differential equations, sufficient conditions are derived to achieve the cluster-delay consensus. Finally, simulation experiments are conducted to illustrate and validate our control algorithm.

关键词： Multi-Agent Systems Pinning Control White Noise Cluster Consensus Nonlinear Dynamics Time Delay

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金属学报 2018年第7期54卷 1077-1086页

作者：黄明亮孙洪羽大连理工大学材料科学与工程学院先进连接技术辽宁省重点实验室大连116024

采用原位电迁移实验研究了在150℃、1.0×10~4A/cm^2条件下倒装芯片Ni/Sn-3.0Ag-0.5Cu/Ni-P无铅凸点中β-Sn晶粒取向对金属间化合物(IMC)的聚集析出机制、阴极Ni芯片侧(UBM)溶解行为、电迁移失效机制以及电迁移驱动下β-Sn晶粒的旋转滑... 详细信息

采用原位电迁移实验研究了在150℃、1.0×10~4A/cm^2条件下倒装芯片Ni/Sn-3.0Ag-0.5Cu/Ni-P无铅凸点中β-Sn晶粒取向对金属间化合物(IMC)的聚集析出机制、阴极Ni芯片侧(UBM)溶解行为、电迁移失效机制以及电迁移驱动下β-Sn晶粒的旋转滑移机制的影响。原位观察发现,电迁移过程中(Ni,Cu)_3Sn_4类型IMC在凸点中仅沿着β-Sn晶粒的c轴方向析出,且倾向于在θ角(β-Sn晶粒的c轴与电子流动方向之间的夹角)较小的晶粒内析出;同时,阳极附近观察到β-Sn挤出现象,即凸点出现应力松弛。建立了阴极NiUBM溶解量与β-Sn晶粒取向的关系模型:β-Sn晶粒取向决定阴极NiUBM的溶解量,即当θ角很小时,NiUBM会出现明显溶解;当θ角增大时,NiUBM的溶解受到抑制,该模型与实验值基本吻合。电迁移导致β-Sn晶粒发生旋转滑移,认为是由于不同取向的相邻β-Sn晶粒中电迁移导致的空位通量不同,从而导致阳极晶界处于空位的过饱和,阴极晶界处于空位的未饱和状态,并促使空位沿着晶界出入于自由表面,最终在垂直方向上会产生空位梯度,由沿晶界的空位梯度对应的应力梯度产生的力矩使β-Sn晶粒发生旋转滑移。

关键词：电迁移 β-Sn 各向异性阴极溶解 IMC析出晶粒旋转

Cu/Sn-52In/Cu微焊点液-固电迁移行为研究

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金属学报 2017年第5期53卷 592-600页

作者：张志杰黄明亮江苏科技大学材料科学与工程学院镇江212003 大连理工大学材料科学与工程学院大连116024

采用同步辐射实时成像技术对比研究了Cu/Sn-52In/Cu微焊点在120和180℃,2.0×10~4A/cm^2条件下液-固电迁移过程中In、Sn和Cu原子的扩散迁移行为及其对界面反应的影响。由于没有背应力,液-固电迁移条件下Sn-52In焊点中In原子的有效电荷... 详细信息

采用同步辐射实时成像技术对比研究了Cu/Sn-52In/Cu微焊点在120和180℃,2.0×10~4A/cm^2条件下液-固电迁移过程中In、Sn和Cu原子的扩散迁移行为及其对界面反应的影响。由于没有背应力,液-固电迁移条件下Sn-52In焊点中In原子的有效电荷数Z*为负值是其定向扩散迁移至阳极的物理本质,这与Sn-52In焊点固-固电迁移条件下背应力驱使In原子迁移至阴极的机理不同。基于液态金属焓随温度的变化关系,修正了计算液态金属Z*的理论模型,计算获得In原子在120和180℃下的Z*分别为-2.30和-1.14,为电迁移方向提供了判断依据。液-固电迁移过程中In和Cu原子同时由阴极扩散至阳极并参与界面反应使得界面金属间化合物(intermetallic compounds,IMC)生长表现为"极性效应",即阳极界面IMC持续生长变厚,并且厚于阴极界面IMC,温度越高,界面IMC的"极性效应"越显著。液-固电迁移过程中阴极Cu基体的溶解与时间呈抛物线关系,温度越高,阴极Cu的溶解速率越快。

关键词：电迁移 Sn-52In微焊点有效电荷数界面反应金属间化合物