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Modelling of the variation of granular base materials resilient modulus with material characteristics and humidity conditions

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Journal of Road Engineering 2024年第1期4卷 27-35页

作者： Jean-pascal Bilodeau Erdrick Leandro Perez-Gonzalez Ali Saeidi Departement de Genie Civil et Genie des Eaux Universite LavalQuebecG1V 0A6Canada Departement des Sciences Appliquees Universite du Quebeca ChicoutimiChicoutimiG7H 2B1Canada

This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal *** fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water *** results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity *** adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric *** model shows that the variation of Er values is below10%for fully crushed granular ***,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics.

关键词： Resilient modulus Degree of saturation Humidity conditions Unbound granular materials Pavement base

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环保绝缘气体介电强度预测方法评估

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电工技术学报 2023年第S01期38卷 214-221页

作者：周文俊邱睿郑宇 pascal Brault 电网环境保护全国重点实验室(武汉大学) 武汉430072 武汉大学电气与自动化学院武汉430072 法国国家科学研究中心-奥尔良大学GREMI实验室奥尔良45067

为明确各类气体介电强度预测方法的准确性,基于9种气体(N_(2)、CO_(2)、N_(2)O、CF_(4)、SO_(2)F_(2)、c-C_(4)F_(8)、C_(3)F_(8)、C_5F_(10O)和C_(4)F_(7)N)在50 Hz工频交流电场下测得的相对介电强度对5种预测方法进行了评估。结果表明,各方法预测准确性与其给出的可决系数R~2不一致。这主要与其使用的样本数据测试条件不统一、同一气体的相对介电强度不一致有关。当修正上述问题后,各方法准确性得到提升,并与其R~2相符。分子参数的丰富和放电理论的介入可使预测方法准确性提升。使用样本外气体进行验证的方法,其预测结果在修正前后都具有较高的准确性;使用基团贡献法的预测方法也具有上述特性。通过上述评估结果可知,样本中的气体数据需在统一条件下获得,并根据试验条件和样本分子特征确定预测方法的适用范围。放电理论、分子几何特征和新分子参数的引入有助于提高预测模型的准确性。模型验证和基团贡献法可提高预测方法对样本数据的包容性。

关键词：环保绝缘气体介电强度预测构效关系(QSPR) 气体绝缘输电管道(GIL)

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Modelling the long-term geomorphic response to check dam failures in an alpine channel with CAESAR-Lisflood

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International Journal of Sediment Research 2022年第5期37卷 687-700页

作者： Jorge Alberto Ramirez Mirjam Mertin Nadav Peleg pascal Horton Chris Skinner Markus Zimmermann Margreth Keiler Institute of Geography University of Bern Oeschger Centre for Climate Change Research University of Bern Institute of Environmental Engineering ETH Zurich Institute of Earth Surface Dynamics University of Lausanne Energy and Environment Institute University of Hull Department of Geography University of Innsbruck Institute for Interdisciplinary Mountain Research Austrian Academy of Sciences

Globally, between 1950 and 2011 nearly 80,000 debris flow fatalities occurred in densely populated regions in mountainous terrain. Mitigation of these hazards includes the construction of check dams,which limit coarse sediment transport and in the European Alps number in the 100,000s. Check dam functionality depends on periodic, costly maintenance, but maintenance is not always possible and check dams often fail. As such, there is a need to quantify the long-term(10-100 years) geomorphic response of rivers to check dam failures. Here, for the first time, a landscape evolution model(CAESARLisflood) driven by a weather generator is used to replicate check dam failures due to the lack of maintenance, check dam age, and flood occurrence. The model is applied to the Guerbe River,Switzerland, a pre-Alpine catchment containing 73 check dams that undergo simulated failure. Also presented is a novel method to calibrate CAESAR-Lisflood?s hydrological component on this ungauged catchment. Using 100-year scenarios of check dam failure, the model indicates that check dam failures can produce 8 m of channel erosion and a 322% increase in sediment yield. The model suggests that after check dam failure, channel erosion is the remobilization of deposits accumulated behind check dams, and, after a single check dam failure channel equilibrium occurs in five years, but after many check dam failures channel equilibrium may not occur until 15 years. Overall, these findings support the continued maintenance of check dams.

关键词： Landscape evolution model Check dam failure Weather generator Natural hazards

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Positive effects of tree species diversity on litterfall quantity and quality along a secondary successional chronosequence in a subtropical forest

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Journal of Plant Ecology 2017年第1期10卷 28-35页

作者： Yuanyuan Huang Yinlei Ma Ke Zhao pascal A.Niklaus Bernhard Schmid Jin-Sheng He Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University5 Yiheyuan RoadBeijing 100871China Department of Evolutionary Biology and Environmental Studies and Zürich-Basel Plant Science Center University of ZürichWinterthurerstrasse 190CH-8057 ZürichSwitzerland

Aims Litterfall,as an important link between aboveground and belowground processes,plays a key role in forest ***,we test for effects of tree species richness on litter production and litter quality in subtropical *** study further encompasses a factorial gradient of secondary succession that resulted from human *** that a large percentage of subtropical forests are in secondary successional stages,understanding the role of biodiversity on forest re-growth after disturbance appears *** From January 2009 to December 2014,we monitored forest litterfall in 27 Comparative Study Plots that spanned a gradient of tree species richness(3-20 species)and secondary successional ages(~20 to 120 years)in Gutianshan Natural Nature Reserve,Zhejiang Province,*** experiment is part of the biodiversity-ecosystem functioning research platform‘BEF-China’.Tree litterfall was collected in monthly intervals using litter *** were separated into leaf and non-leaf *** litter was further sorted into dominant and other *** level monthly leaf litter C and N contents were analysed through a full *** linear mixed-effects models were applied to test for effects of tree species richness and successional age on litter quantity and leaf litter C/*** Findings Litterfall increased with species richness among and within successional age and this effect was consistent across *** older stands had higher litterfall and this effect was related to increased tree species ***,species richness did not change the intra-and inter-annual temporal stability of *** tree species richness increased leaf litter quality(decreased C/N),while successional age had no *** study indicates that more diverse forest stands produce more leaf litter and that this litter has higher N concentrations,which could promote forest growth through accelerated nutrient re-cycling.

关键词： species richness BEF-China litterfall leaf litter C/N subtropical forest secondary succession structural equation models

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道路公共交通效率的随机前沿分析方法

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交通运输系统工程与信息 2013年第5期13卷 64-71页

作者： Sami Jarboui pascal Forget Younes Boujelbene 斯法克斯大学经济与管理学院魁北克特瓦河大学工程学院

本文旨在测算18个城市共64个道路公共交通运营商的技术效率,并研究各因素对这些企业效率水平的影响程度.随机前沿分析(SFA)方法采用从2000年至2011年共计12年的样本数据.结果表明,营业利润、资本投入和企业规模都是影响技术效率水平的... 详细信息

本文旨在测算18个城市共64个道路公共交通运营商的技术效率,并研究各因素对这些企业效率水平的影响程度.随机前沿分析(SFA)方法采用从2000年至2011年共计12年的样本数据.结果表明,营业利润、资本投入和企业规模都是影响技术效率水平的重要因素.计算得出的道路公共交通运营商的技术效率水平在0.46至0.95之间.投资较多的大规模运营商比小规模运营商技术效率更高,发达国家的运营商比发展中国家表现出更高的技术效率.

关键词：城市交通效率道路公共交通随机前沿分析

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A New Interpretation of the Hubble Law

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Journal of Modern Physics 2015年第9期6卷 1227-1232页

作者： pascal Churoux Montgailhard France

We propose a new interpretation of Hubble law. Waves are observed in the observer space-time. It defines the observer proper time T. Space-time is composed of three spatial dimensions and three temporal parameters: proper-time s of the observed object, proper time T of the observer and integration time t (currently considered as relative time). Time origin is the birth of the universe. So, universe is stable;it can be seen as the comobile space of expansion theory. When changing space-time from the source to the observer, waves are seen cooling;this explains the redshift effect. The distance is defined as the product of the delay time with the local speed of light of the observer. The mistake between t and T can explain why universe is viewed as not only in expansion but also in acceleration whereas we think it is stable.

关键词： Hubble Law Space-Time Light Speed Universe Expansion Redshift

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Topological Properties of the Catastrophe Map of a General Equilibrium Production Model with Uncertain States of Nature

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Applied Mathematics 2014年第17期5卷 2719-2727页

作者： pascal Stiefenhofer University College London London UK

This paper shows existence and efficiency of equilibria of a production model with uncertainty, where production is modeled in the demand function of the consumer. Existence and efficiency of equilibria are a direct consequence of the catastrophe map being smooth and proper. Topological properties of the equilibrium set are studied. It is shown that the equilibrium set has the structure of a smooth submanifold of the Euclidean space which is diffeomorphic to the sphere implying connectedness, simple connectedness, and contractibility. The set of economies with discontinuous price systems is shown to be of Lebesgue measure zero.

关键词： Differential Topology General Equilibrium Uncertainty Production

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Homozygosity for the CD1E★02 allele is associated with a resistance to Plasmodium falciparum malaria infection in Gabonese school children

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 195-198页

作者： Landry-Erik Mombo Francine Ntoumi Cyrille Bisseye Rajendranath Ramasawmy pascal Millet Ryad Tamouza Centre International de Recherches Medicales de Franceville(CIRMF) BP 769FrancevilleGabon INSERM U458 Hopital Robert Debre48 Bd Serurier75019 ParisFrance Laboratoire d'Immunologie et d'Histocompatibilite AP-HP IUH and INSERM U662Hopital Saint-LouisParisFrance

Objective:To explore the possible association between polymorphisms in CD1 genes and both asymptomatic and mild Plasmodium falciparum ***:Two clusters of 85 school children,from the village of Dienga(Gabon) were *** first group was analysed for the prevalence and the multiplicity of asymptomatic Plasmodium falciparum infection,whereas the second group was screened for the frequency of malarial ***:Our findings showed that homozygosity for the CD1E★02 allele was associated with a low frequency of malarial ***,a strong association between CD1E★02 homozygotes and the resistance to multiple malarial attacks was *** CD1A★01 allele showed a weak association with a small number of malarial ***:Our results suggest a possible role of CD1E polymorphisms in malaria protection among school children and that CD1e molecules are involved in anti-malarial immunity.

关键词： CD1E CD1A Malaria GPI Gabon

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Techno-economic analysis of sidestream ammonia removal technologies:Biological options versus thermal stripping

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Environmental Science and Ecotechnology 2023年第1期13卷 107-114页

作者： pascal Ochs Ben Martin Eve Germain-Cripps Tom Stephenson Mark van Loosdrecht Ana Soares Cranfield University College RoadCranfieldBedfordMK430ALUnited Kingdom Thames Water Reading STWIsland RoadRG20RPReadingUnited Kingdom Delft University of Technology Building 58Van der Maasweg 92629DelftNetherlands

Over the past twenty years,various commercial technologies have been deployed to remove ammonia(NH4eN)from anaerobic digestion(AD)*** recent years many anaerobic digesters have been upgraded to include a pre-treatment,such as the thermal hydrolysis process(THP),to produce more biogas,increasing NH4eN concentrations in the liquors are costly to *** study provides a comparative techno-economic assessment of sidestream technologies to remove NH4eN from conventional AD and THP/AD dewatering liquors:a deammonification continuous stirred tank reactor(PNA),a nitrification/denitrification sequencing batch reactor(SBR)and thermal ammonia stripping process with an ammonia scrubber(STRIP).The SBR and PNA were based on full-scale data,whereas the STRIP was designed using a computational approach to achieve NH4eN removals of 90e95%.The PNA presented the lowest whole-life cost(WLC)over 40 years,with£7.7 M,while the STRIP had a WLC of£43.9 *** study identified that THP dewatering liquors,and thus a higher ammonia load,can lead to a 1.5e3.0 times increase in operational expenditure with the PNA and the ***,this study highlighted that deammonification is a capable and cost-effective nitrogen removal *** like the STRIP respond to current pressures faced by the water industry on ammonia recovery together with targets to reduce nitrous oxide ***,ammonia striping-based processes must further be demonstrated in WWTPs and WLC reduced to grant their wide implementation and replace existing technologies.

关键词： Deammonification Nitrification Denitrification Wastewater Sludge dewatering liquors

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不同水基防腐剂处理木材的表面自由能

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北京林业大学学报 2006年第4期28卷 1-5页

作者：曹金珍 D.pascal Kamdem 北京林业大学材料科学与技术学院美国密歇根州立大学林学系

该研究中测定了蒸馏水、二碘甲烷、甲酰胺和甘油等4种参照液体在不同水基防腐处理(包括铬化砷酸铜CCA以及另外两种商品名为NW和NS的处理)后的木材表面所形成的接触角,并根据酸碱作用理论计算得到其表面自由能及其两个分量———Lifshizv... 详细信息

该研究中测定了蒸馏水、二碘甲烷、甲酰胺和甘油等4种参照液体在不同水基防腐处理(包括铬化砷酸铜CCA以及另外两种商品名为NW和NS的处理)后的木材表面所形成的接触角,并根据酸碱作用理论计算得到其表面自由能及其两个分量———LifshizvanderWaals(LW)分量和酸碱作用(AB)分量.结果表明,NW和CCA处理使木材表面的疏水性有所增加,而NS处理由于早材的水分渗透速率加快总体表现为亲水性增加.利用蒸馏水、二碘甲烷、甲酰胺这3种参照液体计算得到的未处理早材、未处理晚材、CCA处理早材、CCA处理晚材、NW处理早材、NW处理晚材、NS处理早材和NS处理晚材的表面自由能分别为43.1、44.5、43.4、45.1、49.4、40.6、46.0和40.9mJm2.由此可见,CCA处理材的表面自由能接近于未处理材,而经过NW和NS处理后,早材和晚材的表面能都有一定程度的变化,但对于木材整体来说表面自由能仍接近于未处理材.

关键词：木材表面自由能防腐剂接触角

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