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Evaluation of ERA5 Temperature and Precipitation Dataset over Fujian Province of China

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Evaluation of ERA5 Temperature and Precipitation Dataset ove...

作者： AMANDU dennis 福建师范大学

学位级别：硕士

尽管过去20年来,再分析数据已在世界范围内得到广泛应用,但ECMWF生产的最新一代再分析资料ERA5尚未在局地尺度上进行评估。再分析资料可以有效提高全球气候模式温度和降水的可靠性。本研究采用福建省22个气象站的月气温(月最高气温、月... 详细信息

尽管过去20年来,再分析数据已在世界范围内得到广泛应用,但ECMWF生产的最新一代再分析资料ERA5尚未在局地尺度上进行评估。再分析资料可以有效提高全球气候模式温度和降水的可靠性。本研究采用福建省22个气象站的月气温(月最高气温、月最低气温和月平均气温)和月总降水量数据,评估了1979-2019年ERA5月气温和月降水数据的可靠性。结果表明,ERA5能够较好的捕捉福建省气温和降水的时间趋势。观测值与ERA5之间的气温相关系数范围为0.996至0.999。所有台站的RMSE范围在0.36℃至5.49℃之间,平均值为1.08℃。ERA5月最低气温、月最高气温和月平均气温与观测值的相关性为0.87～0.89。所有台站年降水的相关系数为0.6至0.81,平均为0.7,表明ERA5的年降水模拟较好。最大的降水RMSE出现在浦城站,为625.59mm,误差范围为-138.8mm至529.4mm,年降水平均值为148.2mm。ERA5数据的误差来源主要是ERA5网格点与观测站的海拔高度差异。

关键词：再分析资料气温降水偏差福建省

Modeling and Validation of Base Pressure for Aerodynamic Vehicles Based on Machine Learning Models

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2331-2352页

作者： Jaimon dennis Quadros Sher Afghan Khan Abdul Aabid Muneer Baig Senior Lecturer of Mechanical Engineering University of BoltonRAK Academic CenterRas Al Khaimah16038UAE Department of Mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaSelangor53100Malaysia Department of Engineering Management College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia

The application of abruptly enlarged flows to adjust the drag of aerodynamic vehicles using machine learning models has not been investigated *** process variables(Mach number(M),nozzle pressure ratio(η),area ratio(α),and length to diameter ratio(γ))were numerically explored to address several aspects of this process,namely base pressure(β)and base pressure with cavity(βcav).In this work,the optimal base pressure is determined using the PCA-BAS-ENN based algorithm to modify the base pressure presetting accuracy,thereby regulating the base drag required for smooth flow of aerodynamic *** on the identical dataset,the GA-BP and PSO-BP algorithms are also compared to *** data for training and testing the algorithmswas derived using the regression equation developed using the Box-Behnken Design(BBD).The results show that the PCA-BAS-ENN model delivered highly accurate predictions when compared to the other two *** a result,the advantages of these results are two-fold,providing:(i)a detailed examination of the efficiency of different neural network algorithms in dealing with a genuine aerodynamic problem,and(ii)helpful insights for regulating process variables to improve technological,operational,and financial factors,simultaneously.

关键词： High speed flow Mach number machine learning PCA-BAS-ENN algorithm

SYSTEMS ENGINEERING RESEARCH

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Journal of Systems Science and Systems Engineering 2008年第3期17卷 319-333页

作者： Abd-El-Kader SAHRAOUI dennis M.BUEDE Andrew P.SAGE LAAS-CNRS and Universitéde Toulouse 7 Avenue du Colonel Roche Toulouse31077France Innovative Decisions Inc.2139 Golf Course Dr.RestonVA 20191 USA Dept.of Systems Engineering and Operations Research George Mason UniversityFairfaxVA 22030 USA

In this paper, we propose selected research topics that are believed central to progress and growth in the application of systems engineering （SE）. As a professional activity, and as an intellectual activity, systems engineering has strong links to such associated disciplines as decision analysis, operation research, project management, quality management, and systems design. When focussing on systems engineering research, we should distinguish between subjects that are of systems engineering essence and others that more closely correspond to those that are more relevant for related disciplines.

关键词： Systems engineering systems of systems requirements engineering systems families

Low-cost and efficient Mn/CeO_(2) catalyst for photocatalytic VOCs degradation via scalable colloidal solution combustion synthesis method

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Journal of Materials Science & Technology 2022年第21期116卷 169-179页

作者： Yingguang Zhang Muyan Wu Yifei Wang Xiaolong Zhao dennis Y.C.Leung Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518000China

Colloidal solution combustion synthesis(CSCS)is a simple and easy method for mass-production of crystalline nanomaterials with tunable pore *** this work,mesoporous Mn/CeO_(2) catalysts were fabricated via CSCS method coupled with a dip-coating process and used for photocatalytic oxidation(PCO)of *** vacuum ultraviolet(VUV)irradiation,a high toluene removal efficiency of about 92%was achieved with a toluene reaction rate of about 118μmol/g/h in a continuous flow reactor.A possible degradation pathway was proposed based on the analysis of intermediates by Fourier transform infrared photoluminescence spectra(FTIR)and *** temperature-programmed reduction(H_(2)-TPR),Brunauer-Emmett-Teller(BET)surface areas,photoluminescence spectra(PL)spectra and X-ray photoelectron spectroscopy(XPS)were carried out to analyze physical and chemical properties of the *** with Mn_(x)Ce_(1-x)O_(2) catalysts synthesized by one step CSCS method,Mn/CeO_(2) has a higher photocatalytic activity,which is attributed to the presence of higher contents of Ce^(3+),Mn^(2+)and Mn^(3+)*** presence of higher contents of these species plays a key role in the activity enhancement of toluene oxidation and ozone *** method is facile,efficient and scalable,and it may become a promising industrial application technology for catalyst synthesis in the near future.

关键词： Mesoporous CeO_(2) Manganese modification Scalable synthesis Photocatalysis VOCs abatement

Quasi-exactly solvable decatic model description of nuclei near the X(5) critical point

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Communications in Theoretical Physics 2022年第1期74卷 46-56页

作者： Hadi Sobhani Hassan Hassanabadi dennis Bonatsos Feng Pan Jerry P Draayer Department of Physics Liaoning Normal UniversityDalian 116029China Faculty of Physics Shahrood University of TechnologyShahroodIran Institute of Nuclear and Particle Physics National Centre for Scientific Research‘Demokritos’GR-15310 Aghia ParaskeviAttikiGreece Department of Physics and Astronomy Louisiana State UniversityBaton RougeLA 70803-4001United States of America

The Bohr Hamiltonian with axially deformed shape confined in a quasi-exactly solvable decatic β-part potential is *** is shown that the decatic model can well reproduce the X(5)model results as far as the energy ratios in the ground and beta band and related B(E2)values are *** results to the low-lying energy ratios and relevant B(E2)values of even-even X(5)candidates ^(150)Nd,^(156)Dy,^(164)Yb,^(168)Hf,^(174)Yb,^(176,178,180)Os,and ^(188,190)Os show that the decatic model provides the best fitting results for the energy ratios,while the X(5)model is the best at reproducing the B(E2)values of these nuclei,in which the beta-bandhead energy is lower than that of the gamma *** for even-even nuclei,such as ^(154,156,158)Gd,with bandhead energies of the beta and gamma bands more or less equal within the X(5)critical point to the axially deformed region,our numerical analysis indicates that the decatic model is better than the X(5)model in describing both the low-lying level energies and related B(E2)values.

关键词： Bohr Hamiltonian the decatic potential X(5)critical point

The West in the World A Mid-Length Narrative History: Renaissance to Present dennis Sherman, Joyce Salisbury 2nd ed.; Updated.

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城市电动自行车设计,当极简主义遇见使用质量

2006年

作者： dennis Sherman Joyce Salisbury

Includes bibliographical references and index.

ISBN: (纸本)007297320X

Includes bibliographical references and index.

关键词： Civilization Western

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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工业设计 2024年第1期 23-23页

作者： Alexander Forst dennis Fiedler 不详

这款城市电动自行车从轻巧与创新的车架结构、流畅的造型语言、惊人的高度集成,到出色的设计和制造质量,在各个层面上都达到了非常高的质量标准。盘式制动器、灯和遥控器的电缆巧妙地藏在车体内,将操作刹车的杠杆支架集成在车把中,将照... 详细信息

这款城市电动自行车从轻巧与创新的车架结构、流畅的造型语言、惊人的高度集成,到出色的设计和制造质量,在各个层面上都达到了非常高的质量标准。盘式制动器、灯和遥控器的电缆巧妙地藏在车体内,将操作刹车的杠杆支架集成在车把中,将照明系统完全集成在车架中。此外,重量轻、紧凑的电机还与下管无缝融合,使整辆车充满动感、极致简约。

关键词：电动自行车极简主义盘式制动器照明系统车架结构无缝融合质量标准遥控器

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Application of the Shrinking Particle Model for the Evaluation of Molecular Recyclability of PET versus Semi-Aromatic Polyesters

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Preface for the article collection “Ecohydrological Processes and Ecosystem Services”

Open Journal of Physical Chemistry（物理化学期刊） 2024年第2期 21页

作者： Jack van Schijndel Sanne de Krom dennis Molendijk Koen van Beurden Amarante Böttger

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Ecological Processes 2018年第1期7卷 78-80页

作者： Ge Sun dennis W.Hallema Heidi Asbjornsen Eastern Forest Environmental Threat Assessment Center Southern Research StationU.S.Department of Agriculture Forest Service920 Main Campus Dr.Suite 300RaleighNC 27606USA Oak Ridge Institute for Science and Education U.S.Department of EnergyOak RidgeTNUSA Institute for the Study of Earth Oceansand SpaceUniversity of New HampshireDurhamNHUSA

Water is essential to life on ***,the study of interactions between ecological and hydrological processes,is fundamental to our understanding and quantification of services provided by *** knowledge of ecohydrology is incomplete due to the complex nature of ecosystems,which are constantly changing under multiple stresses from air pollution to climate change,from deforestation to urbanization,and from soil erosion to soil *** services,the goods and services that ecosystems provide for human wellbeing,are increasingly adopted as a framework worldwide for ecological restoration and conservation,watershed management,and sustainable development policy making.

关键词： services soil Services