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中国科学（D辑） 2005年第A1期35卷 167-176页

作者：颜鹏黄健 r.draxler 北京大学大气科学系中国气象科学研究院北京100081 中国气象局广州热带海洋气象研究所 NOAAArL Silver SpringMD20910USA

采用分行业、分季节、高分辨的北京市SO2排放源清单,和NCEP气象分析场资料,用HYSPLIT-4(HybridSingleParticleLagrangianIntegratedTrajectory)污染扩散模式,计算了北京2000年和2001年地面SO2逐日变化,分析了北京当地及周边地区不同类... 详细信息

采用分行业、分季节、高分辨的北京市SO2排放源清单,和NCEP气象分析场资料,用HYSPLIT-4(HybridSingleParticleLagrangianIntegratedTrajectory)污染扩散模式,计算了北京2000年和2001年地面SO2逐日变化,分析了北京当地及周边地区不同类型排放源对北京地面SO2的影响.与实测值对比表明,模式能够较好的模拟出北京地面SO2的逐日变化特点和季节分布.计算的各种排放源对北京的影响说明,总体上,北京当地排放影响较大,周边源影响大约占20%左右,但在一定天气条件下,周边源贡献仍可超过30%以上,甚至个别时候超过40%;如果考虑周边源的采暖期源强增大一倍,则采暖期周边源平均贡献2000年和2001年分别增加到35%和40%.对北京市划分的7类排放源分别计算其对北京地面SO2的浓度贡献率发现,在北京市区的各类排放源中,占北京市区排放量较少部分(不到三分之一)的工业面源和锅炉面源对北京市区的SO2贡献很大,是北京市SO2污染治理的关键.

关键词：北京地面SO2 周边及当地不同类型排放源污染治理

The long-term simulation of surface SO_2 and evaluation of contributions from the different emission sources to Beijing city

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Science China Earth Sciences 2005年第Z2期48卷 196-208页

作者： roland draxler NOAAArL Silver SpringMD 20910USA

With a high-resolution SO2 emission inventory categorized by industries and seasons for Beijing city and gridded meteorological data fields from NCEP, the pollution dispersion model, HYSPLIT4 (Hybrid Single Particulate Lagrangian Integrated Trajectory, version 4), is used to determine the day-to-day variation of surface SO2 in Beijing for 2000 and 2001. Furthermore,the contributions of different emission sources in and around Beijing to the surface SO2 are studied. As shown in comparison with observations, the model does well in simulating the daily variation and seasonal distribution. The model computation of the annual source contributions to Beijing surface SO2 indicates that local emissions from the city give the largest contribution and the sources from the surrounding regions contribute only about 20%. During SO2 polluted or unpolluted days, the contribution from the latter can exceed 30%, and depending upon weather conditions, the contribution may exceed 40%. If the emissions from the surrounding sources during the winter heating season are assumed to be doubled in intensity, their contribution to surface SO2 in Beijing increased from 21% to 35% and 25% to 40% in 2000 and 2001, respectively. Evaluation of 7 types of emission sources identified for Beijing for their relative contribution to the concentration of surface SO2 has shown that area emissions by industrial production and furnaces, though discharging relatively small amounts (less than 1/3 of the total), have the largest contribution to the urban surface SO2, which is the key to the mitigation of the pollutant in the city.

关键词： surface SO2 in Beijing, contributions of different types of emission, mitigation of pollution.

利用HYSPLIT_4模式分析珠海地面SO_2浓度的变化规律

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热带气象学报 2002年第4期18卷 407-414页

作者：黄健颜鹏 roland r.draxler 广州热带海洋气象研究所广东广州510080 中国气象科学研究院北京100081 NOAAArL.115EastWestHWY

利用HYSPLIT_4传输、扩散模式,模拟大尺度气象场下的1999年10月～2000年1月珠海地面SO2浓度变化规律,结果与实测资料对比表明,模式较好地模拟出珠海地面SO2的浓度水平和变化趋势。模拟结果经过分析还表明,珠海地面SO2浓度受到广东省其... 详细信息

利用HYSPLIT_4传输、扩散模式,模拟大尺度气象场下的1999年10月～2000年1月珠海地面SO2浓度变化规律,结果与实测资料对比表明,模式较好地模拟出珠海地面SO2的浓度水平和变化趋势。模拟结果经过分析还表明,珠海地面SO2浓度受到广东省其它地区尤其是珠江三角洲地区城市污染源排放的影响;其浓度变化与广州900 m高度(或965 hPa等压面)水平风场具有相当好的对应关系。

关键词：珠海 HYSPLIT_4模式污染源变化规律二氧化硫

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周边地区对北京地面SO_2影响的初步研究

应用气象学报 2002年第U1期13卷 144-152页

作者：颜鹏黄健 roland draxler 中国气象科学研究院北京100081 广东省气象局广州510080 NOAA ArL Silver Spring

采用Lagrangian传输、扩散、沉降模式计算了 1 994年 9、1 0月份 (非采暖期 )、1 995年 1月和 2 0 0 0年 1月 (采暖期 )北京地区SO2 的变化规律 ,并分别计算了北京市不同类型的排放源以及周边地区污染源对平均地面SO2 浓度的贡献。计算... 详细信息

采用Lagrangian传输、扩散、沉降模式计算了 1 994年 9、1 0月份 (非采暖期 )、1 995年 1月和 2 0 0 0年 1月 (采暖期 )北京地区SO2 的变化规律 ,并分别计算了北京市不同类型的排放源以及周边地区污染源对平均地面SO2 浓度的贡献。计算结果与实际观测资料对比表明 ,模式能够较好地模拟北京地区SO2 的浓度量级和逐日变化趋势。北京地区地面SO2 浓度受天气条件的影响较大。采暖期 ,北京当地排放源的影响相对较大 ;但在大气条件有利输送的背景下。

关键词： Lagrangian扩散模式来源北京大气周边地区地面二氧化硫浓度污染物

Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN D.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

Acute lung injury and ArDS in acute pancreatitis: Mechanisms and potential intervention

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World Journal of Gastroenterology 2010年第17期16卷 2094-2099页

作者： roland Andersson Department of Surgery Clinical Sciences LundLund University Lund University Hospital SE-221 85 LundSweden

Acute lung injury (ALI) and acute respiratory distress syndrome (ArDS) in acute pancreatitis still represents a substantial problem,with a mortality rate in the range of 30%-40%.The present review evaluates underlying pathophysiological mechanisms in both ALI and ArDS and potential clinical *** mediators and pathophysiological pathways are involved during the different phases of ALI and *** initial exudative phase is characterized by diffuse alveolar damage,microvascular injury and influx of inflammatory *** phase is followed by a fibro-proliferative phase with lung repair,type Ⅱ pneumocyte hypoplasia and proliferation of *** derived from polymorphonuclear neutrophils,various pro-inflammatory mediators,and phospholipases are all involved,among *** factors that promote pancreatitis-associated ALI may be found in the gut and mesenteric *** is a lack of complete understanding of the underlying mechanisms,and by improving our knowledge,novel tools for prevention and intervention may be developed,thus contributing to improved outcome.

关键词： Acute lung injury Acute respiratory distress syndrome Acute pancreatitis Etiology Pathophysiology