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modeling the dynamic impacts of maritime network blockage on global supply chains

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The Innovation 2024年第4期5卷 103-109,102页

作者： Shen Qu Yunlei She Qi zhou Jasper Verschuur Lu-Tao Zhao Huan Liu Ming Xu yi-Ming wei Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China School of Management Beijing Institute of TechnologyBeijing 100081China Beijing Key Lab of Energy Economics and Environmental Management Beijing 100081China Oxford Programme for Sustainable Infrastructure Systems(OPSIS) Environmental Change InstituteUniversity of OxfordOX12JD OxfordUK State Key Joint laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key laboratory of Sources and Control of Air Pollution Complex Beijing 100084China School of Environment Tsinghua UniversityBeijing 100084China

Recent phenomena such as pandemics,geopolitical tensions,and climate change-induced extreme weather events have caused transportation network interruptions,revealing vulnerabilities in the global supply chain.A salient example is the March 2021 Suez Canal blockage,which delayed 432 vessels carrying cargo valued at$92.7 billion,triggering widespread supply chain *** ability to model the spatiotemporal ramifications of such incidents remains *** fill this gap,we develop an agent-based complex network model integrated with frequently updated maritime *** Suez Canal blockage is taken as a case *** results indicate that the effects of such blockages go beyond the directly affected countries and *** Suez Canal blockage led to global losses of about$136.9($127.5–$147.3)billion,with India suffering 75%of these *** losses show a nonlinear relationship with the duration of blockage and exhibit intricate trends post *** proposed model can be applied to diverse blockage scenarios,potentially acting as an earlyalert system for the ensuing supply chain ***,high-resolution daily data post blockage offer valuable insights that can help nations and industries enhance their resilience against similar future events.

关键词： chains valued extreme

面向城市生物多样性提升的可持续景观格局构建机理与途径

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生态学报 2024年第14期44卷 5905-5913页

作者：刘珍环魏莱周义中山大学地理科学与规划学院广东省粤北岩溶区碳水耦合野外科学观测研究站广州510006

城市生物多样性是全球生物多样性的重要组成部分,城市是地理学、生态学及风景园林学等学科领域关注的核心地域。城市生态系统退化直接或间接地干扰了城市生境并造成了区域生物多样性丧失。为实现可持续城市和社区(SDG11)和陆地生物(SDG... 详细信息

城市生物多样性是全球生物多样性的重要组成部分,城市是地理学、生态学及风景园林学等学科领域关注的核心地域。城市生态系统退化直接或间接地干扰了城市生境并造成了区域生物多样性丧失。为实现可持续城市和社区(SDG11)和陆地生物(SDG15)两项可持续发展目标,提升城市生物多样性的途径是当前城市生物多样性研究热点。可持续景观格局调控与构建是提升生物多样性的可能途径,城市生境与生物多样性的关系是可持续景观格局构建的重要内涵,科学地认知两者的相互作用关系是景观格局调控的根本。研究通过梳理生物多样性与景观生态学的交叉研究,提出了可持续城市景观格局研究的转变趋向:从生物多样性保护的被动适应式的生态安全格局构建转向主动调控提升生物多样性的可持续城市景观格局构建。加强多尺度的级联,在斑块尺度上的城市生境恢复和营建,景观尺度上构建面向城市生物多样性提升的可持续景观格局识别与连通优化,区域尺度上开展生物多样性保护规划。研究为城市生物多样性的保护与提升提供科学途径,进而促进城市景观生态学的理论与实践发展。

关键词：生物多样性城市生境可持续景观格局城市

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油藏组分模型的无网格扩展有限体积法

计算力学学报 2024年第4期41卷 709-717,748页

作者：饶翔徐云峰刘伟周玉辉刘怡娜长江大学油气钻采工程湖北省重点实验室武汉430100 长江大学石油工程学院武汉430100 阿卜杜拉国王科技大学物理科学与工程部Ali I.Al-Naimi石油工程研究中心沙特阿拉伯吉达23955-6900

本文开发了油藏组分模型的首个无网格数值求解器。该无网格求解器使用生成时受拓扑约束较少的点云和扩展有限体积法分别离散油藏计算域和控制方程,可以直接使用网格类模拟器中已有的非线性求解器计算全局非线性离散方程组而获取油藏计... 详细信息

本文开发了油藏组分模型的首个无网格数值求解器。该无网格求解器使用生成时受拓扑约束较少的点云和扩展有限体积法分别离散油藏计算域和控制方程,可以直接使用网格类模拟器中已有的非线性求解器计算全局非线性离散方程组而获取油藏计算域压力、相饱和度和组分浓度的分布。采用两个典型的油藏组分模型算例(包括CO_(2)驱和蒸汽驱)用以检验该无网格模拟器的计算表现。算例结果表明,相较于网格类方法,该无网格模拟器能够显著降低对复杂油藏计算域的离散难度,且能避免笛卡尔网格有限体积法的网格取向效应,提高了计算精度和非线性求解的收敛效率。

关键词：广义有限差分方法无网格扩展有限体积法油藏组分模型,油藏数值模拟

A Comparative Study on Asperity Peak modeling methods

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 137-150页

作者： wei zhou Daiyan Zhao Jinyuan Tang Jun yi Hunan Provincial Key laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and TechnologyXiangtan 411201China State Key laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China

The peak identification scheme based method(three-point definition)and the spectral moments based method(spectral moment approach)are both widely used for asperity peak modeling in *** discover the differences between the two methods,a great number of rough surface profile samples with various statistical distributions are first randomly generated using *** the distribution parameters of asperity peaks are calculated for the generated samples with both *** obtained results are compared and verified by *** variation rules of the differences between the two methods with statistical characteristics of rough surfaces are *** explain for the discovered differences,the assumptions by spectral moment approach that the joint distribution of surface height,slope and curvature is normal and that the height distribution of asperities is Gaussian,are *** results show that it is unreasonable to assume a joint normal distribution without inspecting the correlation pattern of[z],[z′]and[z′′],and that the height distribution of asperities is not exactly Gaussian before correlation length of rough surface increases to a certain extent,20 for instance.

关键词： Surface topography Roughness Surface analysis Asperity peak Random process model

基于非增强CT的影像组学识别动脉致密征阴性的大脑中动脉闭塞的初步研究

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中国脑血管病杂志 2024年第5期21卷 297-305页

作者：周怡瞿航赵义王苇郝慧婷班淇琦闫晓辉扬州大学附属医院影像科 225002

目的探究基于非增强CT(NCCT)的影像组学识别动脉致密征(HAS)阴性的急性单侧大脑中动脉闭塞(MCAO)的价值。方法回顾性连续纳入2.15年1月至2023年6月就诊于扬州大学附属医院卒中中心或急诊科,经血管成像[MR血管成像(MRA)或CT血管成像(CTA)... 详细信息

目的探究基于非增强CT(NCCT)的影像组学识别动脉致密征(HAS)阴性的急性单侧大脑中动脉闭塞(MCAO)的价值。方法回顾性连续纳入2.15年1月至2023年6月就诊于扬州大学附属医院卒中中心或急诊科,经血管成像[MR血管成像(MRA)或CT血管成像(CTA)或DSA]检查证实的急性单侧MCAO且NCCT表现为HAS阴性的患者80例;在NCCT图像上以每例患者的患侧MCAO段及正常侧对应节段血管作为感兴趣区,共提取108个影像组学特征。使用最小绝对收缩和选择算子(LASSO)筛选关键特征,构建并计算出影像组学评分,分别建立支持向量机(SVM)、光梯度提升机(LightGBM)、梯度提升(GradientBoosting)及自适应提升(AdaBoost)4种影像组学模型以预测MCAO。通过受试者工作特征(ROC)曲线评价不同模型的预测效能,并使用Delong检验方法进行各模型ROC间的比较,最后通过临床决策曲线分析(DCA)评估影像组学模型的应用价值。结果基于160根血管的NCCT图像最终筛选出6个关键特征,分别为偏度、能量、灰度大小区域矩阵(GLSZM)-灰度不均匀性、GLSZM-低灰度区域强调、GLSZM-尺寸区非均匀性标准化、GLSZM-区域熵。SVM模型测试集预测急性单侧MCAO的ROC曲线下面积为0.688(95%CI:0.497~0.878),精确度为0.688;LightGBM模型测试集的曲线下面积为0.787(95%CI:0.620~0.955),精确度为0.781;GradientBoosting模型测试集的曲线下面积为0.654(95%CI:0.457~0.852),精确度为0.688;AdaBoost模型测试集的曲线下面积为0.707(95%CI:0.515~0.899),精确度为0.750。Delong检验显示,LightGBM模型测试集与GradientBoosting模型测试集间的曲线下面积差异有统计学意义(P=0.040),余模型测试集间曲线下面积差异均无统计学意义(均P>0.05)。DCA显示,LightGBM模型表现较好。结论基于NCCT的影像组学对于识别HAS阴性的急性单侧MCAO具有较好的诊断效能,该结论尚需多中心、大样本研究进一步验证。

关键词：大脑中动脉闭塞非增强CT 动脉致密征阴性影像组学

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基于多标签学习的代码评审意见质量评价

软件学报 2024年第6期35卷 2775-2794页

作者：杨岚心张贺徐近伟张逸凡王梓宽周鑫李京悦荣国平南京大学软件学院江苏南京210093 计算机软件新技术国家重点实验室(南京大学) 江苏南京210093 Department of Computer Science Norwegian University of Science and TechnologyTrondheim 7030Norway

代码评审是现代软件开发过程中被广泛应用的最佳实践之一,其对于软件质量保证和工程能力提升都具有重要意义.代码评审意见是代码评审最主要和最重要的产出之一,其不仅是评审者对代码变更的质量感知,而且是作者修复代码缺陷和提升质量的... 详细信息

代码评审是现代软件开发过程中被广泛应用的最佳实践之一,其对于软件质量保证和工程能力提升都具有重要意义.代码评审意见是代码评审最主要和最重要的产出之一,其不仅是评审者对代码变更的质量感知,而且是作者修复代码缺陷和提升质量的重要参考.目前,全球各大软件组织都相继制定了代码评审指南,但仍缺少针对代码评审意见质量的有效的评价方式和方法.为了实现可解释的、自动化的评价,开展文献综述、案例分析等若干实证研究,并在此基础上提出一种基于多标签学习的代码评审意见质量评价方法.实验使用某大型软件企业的34个商业项目的共计17000条评审意见作为数据集.结果表明所提出的方法能够有效地评价代码评审意见质量属性和质量等级.除此以外,还提供若干建模经验,如评审意见标注和校验等,旨在帮助那些受代码评审困扰的软件组织更好地实施所提出的方法.

关键词：软件质量保证代码评审代码评审意见质量评价多标签学习实证软件工程

Effects of Substrate Crystallographic Orientations on Microstructure in Laser Surface-Melted Single-Crystal Superalloy:Theoretical Analysis

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Acta Metallurgica Sinica(English Letters) 2016年第8期29卷 763-773页

作者： Guo-wei Wang Jing-Jing Liang yi-zhou zhou Tao Jin Xiao-Feng Sun Zhuang-Qi Hu Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

A geometric analysis technique for crystal growth and microstructure development in single-crystal welds had been previously *** the effect of welding conditions on the tendency of stray grains formation during solidification was *** the present work,these analytical methods were further *** with an original vectorization method,a 3D Rosenthal solution was used to determine thermal conditions of the ***,the dendrite growth orientation,the dendrite growth velocity and the thermal gradient along dendrite direction were calculated and lively ***,the tendency of stray grains formation in the solidification front was forecasted and its distribution was presented with a 3D *** results indicate that substrate orientation has some impacts on the crystal growth pattern,dendrite growth velocity,distribution of thermal gradient and stray *** on the research methods proposed in this work,any substrate crystallographic orientation can be studied,and predicted stray grains distribution can be visualized.

关键词： Single crystal Laser surface remelting Weld repair modeling Stray grains distribution

Multidisciplinary and Comprehensive Chinese Medicine for Advanced Non-Small Cell Lung Cancer Patients:A Retrospective Study of 855 Cases

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Chinese Journal of Integrative Medicine 2021年第7期27卷 490-495页

作者： HUANG Xian-ge ZHU Li-hua zhou Lei XU wei-jie YAO yi-lin zhou Zhi-yi LI He-gen The Third Department of Oncology Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China

Objective To investigate the effects of multidisciplinary and comprehensive Chinese medicine(CM)treatments on progression-free survival(PFS)and median survival time(MST)in patients with advanced non-small cell lung cancer(NSCLC)and identify factors that influence progression and *** Clinical data of 855 patients with advanced NSCLC who received multidisciplinary and comprehensive CM treatments at Longhua Hospital from January 2009 to December 2.18 were retrospectively *** analysis was performed by the Kaplan-Meier method and log-rank sequential *** analysis of significant variables from the univariate analysis was performed with Cox regression *** factors correlated to progression and prognosis were screened out,and a Cox proportional hazard model was established to calculate the prognostic *** The PFS and MST of 855 advanced NSCLC patients were 9.0 and 26.0 months,*** 1-,2-,3-,and 5-year survival rates were 79.2%,54%,36.2%,and 17.1%,***,pathologic type,and clinical stage were independent prognostic risk factors;surgical history,radiotherapy,treatment course of Chinese patent medicine,intravenous drip of Chinese herbal preparation,duration of oral administration of Chinese herbal decoction(CHD),and intervention measures were independent prognostic protective *** was an independent risk factor for progression,while operation history and oral CHD administration duration were independent protective factors(all Phan male patients,younger patients have higher progression risk but better long-term prognoses than the elderlys,and patients with lower performance status scores are at lower risk for progression and have better *** CM treatments could significantly reduce progression risk,improve pr

关键词： advanced non-small cell lung cancer prognostic factor progression factor survival analysis Chinese medicine

nonlinear adaptive observer-based sliding mode control for LAMOST mount driving

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Research in Astronomy and Astrophysics 2010年第1期10卷 96-106页

作者： Wang-Ping zhou yi Zheng wei Guo Li Yu Chang-Song Yang School of Information ＆ Control Engineering Nanjing University of Information Science ＆ Technology Nanjing 210044 China Nanjing Institute of Astronomical Optics ＆ Technology National Astronomical Observatories Chinese Academy of Sciences Nanjing 210042 China

Heavy disturbances caused mainly by wind and friction in the mount drive system greatly impair the pointing accuracy of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST）. To overcome this negative effect, a third order Higher Order Sliding Mode （HOSM） controller is proposed. The key part of this approach is to design an appropriate observer which obtains the acceleration state. A nonlinear adaptive observer is proposed in which a novel polynomial model is applied to estimate the internal disturbances of the mount drive system. Theoretical analysis demonstrates the stability of the proposed observer. Simulation results show that this nonlinear adaptive observer can obtain a high precision acceleration signal which completes the HOSM controller. Furthermore, the HOSM approach can easily satisfy the position tracking requirements of the LAMOST mount drive system.

关键词： methods analytical - methods numerical - methods laboratory - telescopes