检索结果-南通市图书馆

The use of Artificial Neural Networks to estimate seismic damage and derive vulnerability functions for traditional masonry

引用

Frontiers of Structural and Civil Engineering 2020年第3期14卷 609-622页

作者： Tiago Miguel FERREIRA joao estevao Rui MAIO Romeu VICENTE ISISE Institute of Science and Innovation for Bio-Sustainability(IB-S)Department of Civil EngineeringUniversity of MinhoGuimaraes 4800-058Portugal Department of Civil Engineering University of AlgarveFaro 8005-139Portugal RISCO Department of Civil EngineeringUniversity of AveiroAveiro 3810-193Portugal

ABSTRACT This paper discusses the adoption of Artificial Intelligence-based techniques to estimate seismic damage,not with the goal of replacing existing approaches,but as a mean to improve the precision of empirical methods.For such,damage data collected in the aftermath of the 1998 Azores earthquake(Portugal)is used to develop a comparative analysis between damage grades obtained resorting to a classic damage formulation and an innovative approach based on Artificial Neural Networks(ANNs).The analysis is carried out on the basis of a vulnerability index computed with a hybrid seismic vulnerability asssment methodology,which is subsequently used as input to both approaches.The results obtained are then compared with real post-earthquake damage observation and critically discussed taking into account the level of adjustment achieved by each approach.Finally,a computer routine that uses the ANN as an approximation function is developed and applied to derive a new vulnerability curve expression.In general terms,the ANN developed in this study allowed to obtain much better approximations than those achieved with the original vulnerability approach,which has revealed to be quite non-conservative.Similarly,the proposed vulnerability curve expression was found to provide a more accurate damage prediction than the traditional analytical expressions.

关键词： Artificial Neural Networks seismic vulnerability masonry buildings damage estimation,vulnerability curves

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

溶剂对甘露醇溶解度和磺胺嘧啶溶剂化物相转化的影响

溶剂对甘露醇溶解度和磺胺嘧啶溶剂化物相转化的影响

引用

作者： estevao Genito joao Macaringue 天津大学

学位级别：硕士

结晶是一种将高纯度或者目标晶型的化合物从相对不洁净的溶液中分离和纯化的单元操作。被广泛应用于许多领域,如化工、医药、石油化工和生物技术,以及电子行业等。结晶过程可在气态或熔融态下发生,然而最常见的工业方法是溶液结晶。溶... 详细信息

结晶是一种将高纯度或者目标晶型的化合物从相对不洁净的溶液中分离和纯化的单元操作。被广泛应用于许多领域,如化工、医药、石油化工和生物技术,以及电子行业等。结晶过程可在气态或熔融态下发生,然而最常见的工业方法是溶液结晶。溶剂的种类、溶剂的含量、温度、搅拌条件和其他结晶参数对结晶过程有着很大的影响。本文系统研究了溶剂种类对D-甘露醇溶解度的影响,以及对氮甲基吡咯烷酮(NMP)溶剂化物晶型转变的影响。1.采用实验和分子模拟的手段研究了D-甘露醇在四种混合溶剂中的溶解行为。选取了动态法进行了溶解度数据的测定,而分子动力学模拟(MD)和密度泛函(DFT)计算揭示了溶剂种类对溶解度的影响机制。径向分布函数(RDF)的结果说明了有机溶剂分子对水分子在溶液中的自聚集起到了增强作用,而动力学模拟结果揭示了溶质-有机分子的氢键作用力强弱与溶解度的排序是一一对应的。以上两者共同说明了溶解行为不仅与溶质-溶剂作用有关,溶剂-溶剂之间的相互作用同样起到了重要的作用。为了验证溶解度数据的准确性,采用三种数学模型进行了拟合。最后,混合过程的热力学参数变化(吉布斯自由能、混合熵、混合焓)也进行了计算,结果说明D-甘露醇在所选取溶剂中的溶解过程是熵和焓共同驱动的。2.报道了一种制备具有优异形状与粒度的聚集晶体的溶剂渗透介导相转化方法,其中我们观察到了异常快速的磺胺嘧啶相转变过程。以磺胺嘧啶NMP溶剂化物为初相,通过一个渗水介导的相转变过程,我们得到了磺胺嘧啶的聚合晶体,而且它的形状与粒度与初相保持一致。3.研究了在不同配比下的NMP-水体系中的磺胺嘧啶NMP溶剂化物的溶液介导转晶过程。发现当转晶过程发生于30%NMP的溶剂配比下时,由针状/棒状的溶剂化物转化为了片状的磺胺嘧啶聚结晶体。而当转晶过程发生于60%/70%NMP的溶剂配比下时,最终获得的磺胺嘧啶为棒状的单晶。为了研究溶剂配比对转晶过程的影响机理,我们采用了分子模拟探究了NMP中的溶剂-溶剂相互作用,同时成核速率与转晶过程也借助在线监测手段(FBRM与Raman)分别进行了研究。

关键词： D-甘露醇溶解度磺胺嘧啶 NMP溶剂化物 NMP溶剂水

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Water yield and biomass production for on a eucalypt-dominated Mediterranean catchment under different climate scenarios

引用

林业研究:英文版 2023年第5期34卷 1263-1278页

作者： joao Rocha Ana Quintela Dalila Serpa Jan Jacob Keizer Sérgio Fabres RAIZ-Forest and Paper Research Institute Quinta de S.FranciscoRua JoséEstevao(EN 230-1)3800–783 EixoAveiroPortugal Department of Environment and Planning Centre of Environmental and Marine Studies(CESAM)University of AveiroCampus Universitário de Santiago3810–193 AveiroPortugal

Worldwide,forests are vital in the regulation of the water cycle regulation and in water balance allocation.Knowledge of ecohydrological responses of production forests is essential to support management strategies,especially where water is already scarce.Shifting climatological patterns are expected to impact thermopluviometric regimes,water cycle components,hydrological responses,and plant physiology,evapotranspiration rates,crop productivity and land management operations.This work(1)assessed the impacts of different predicted climate conditions on water yield;(2)inferred the impacts of climate change on biomass production on eucalypt-to-eucalypt succes sion.To this end,the widely accepted Soil and Water Assessment Tool(SWAT)was run with the RCA,HIRHAM5 and RACMO climate models for two emission scenarios(RCP 4.5 and8.5).Three 12-year periods were considered to simulate tree growth under coppice regime.The results revealed an overall reduction in streamflow and water yield in the catchment in line with the projected reduction in total annual precipitation.Moreover,HIRHAM5 and RACMO models forecast a slight shift in seasonal streamflow of up to 2 months(for2024-2048)in line with the projected increase in precipitation from May to September.For biomass production,the extreme climate model(RCA)and severe emis sion scenario(RCP 8.5)predicted a decrease up to 46%.However,in the less extreme and more-correlated(with actual catchment climate conditions)climate models(RACMO and HIRHAM5)and in the less extreme emission scenario(RCP 4.5),biomass production increased(up to 20%),and the growth cycle was slightly reduced.SWAT was proven to be a valuable tool to assess climate change impacts on a eucalypt-dominated catchment and is a suitable decision-support tool for forest managers.

关键词： Climate scenarios Forested catchments Forest ecohydrological modelling Eucalypt biomass production SWAT model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：