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Journal of Rock mechanics and Geotechnical Engineering 2017年第2期9卷 340-349页

作者： R.A.T.m. Ranasinghe m.b. jaksa Y.L. Kuo F. Pooya Nejad School of Civil Environmental and Mining EngineeringUniversity of AdelaideAdelaideAustralia

Rolling dynamic compaction(RDC),which involves the towing of a noncircular module,is now widespread and accepted among many other soil compaction ***,to date,there is no accurate method for reliable prediction of the densification of soil and the extent of ground improvement by means of *** study presents the application of artificial neural networks(ANNs) for a priori prediction of the effectiveness of *** models are trained with in situ dynamic cone penetration(DCP) test data obtained from previous civil projects associated with the 4-sided impact *** predictions from the ANN models are in good agreement with the measured field data,as indicated by the model correlation coefficient of approximately *** is concluded that the ANN models developed in this study can be successfully employed to provide more accurate prediction of the performance of the RDC on a range of soil types.

关键词： Rolling dynamic compaction(RDC) Ground improvement Artificial neural network(ANN) Dynamic cone penetration(DCP) test

Seepage properties of a single rock fracture subjected to triaxial stresses

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Progress in Natural Science:materials International 2007年第12期17卷 1482-1486页

作者： m.b.jaksa 5005 Australia School of Civil and Environmental Engineering University of Adelaide

Coupled properties of seepage and stress fields of rock fractures greatly influence the safety of geotechnical engineering work. based on the closing deformation principle of a single rock fracture, equations describing relationships of aperture and triaxial stresses are developed, and coupled models of seepage and triaxial stresses are proposed. Seepage tests are conducted under triaxial stress conditions by adopting hard granite specimens with an artificial fracture. The results show that the normal stress, lateral stress and seepage pressure significantly affect the flow behavior of rock fractures, and that hydraulic conductivity decreases with increasing normal stress, but increases with rising lateral stress or seepage pressure. In addition, an exponential function provides a good representation of the seepage characteristics of a single rock fracture subjected to triaxial stresses.

关键词： triaxial stresses rock fractures seepage hydraulic conductivity coupling model.

Prediction of the effectiveness of rolling dynamic compaction using artificial neural networks and cone penetration test data

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岩石力学与工程学报 2019年第1期38卷 153-170页

作者： R.A.T.m.Ranasinghe m.b.jaksa F.Pooya Nejad Y.L.Kuo School of Civil Environmental and Mining EngineeringUniversity of Adelaide

Rolling Dynamic Compaction(RDC),which is a ground improvement technique involving non-circular modules drawn behind a tractor,has provided the construction industry with an improved ground compaction capability,especially with respect to a greater influence depth and a higher speed of compaction,resulting in increased productivity. However,to date,there is no reliable method to predict the effectiveness of RDC in a range of ground conditions. This paper presents a new and unique predictive tool developed by means of artificial neural networks(ANNs) that permits a priori prediction of density improvement resulting from a range of ground improvement projects that employed 4-sided RDC modules;commercially known as"impact rollers". The strong coefficient of correlation(i.e. R>0.86) and the parametric behavior achieved in this study indicate that the model is successful in providing reliable predictions of the effectiveness of RDC in various ground conditions.

关键词： soil mechanics rolling dynamic compaction artificial neural networks cone penetration test ground improvement

Genetic programming for predictions of effectiveness of rolling dynamic compaction with dynamic cone penetrometer test results

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Journal of Rock mechanics and Geotechnical Engineering 2019年第4期11卷 815-823页

作者： R.A.T.m.Ranasinghe m.b.jaksa F.Pooya Nejad Y.L.Kuo School of Civil Environmental and Mining Engineering The University of Adelaide

Rolling dynamic compaction (RDC),which employs non-circular module towed behind a tractor,is an innovative soil compaction method that has proven to be successful in many ground improvement *** involves repeatedly delivering high-energy impact blows onto the ground surface,which improves soil density and thus soil strength and ***,there exists a lack of methods to predict the effectiveness of RDC in different ground conditions,which has become a major obstacle to its *** this,in this context,a prediction model is developed based on linear genetic programming (LGP),which is one of the common approaches in application of artificial intelligence for nonlinear *** model is based on in situ density-related data in terms of dynamic cone penetrometer (DCP) results obtained from several projects that have employed the 4-sided,8-t impact roller (bH-1300).It is shown that the model is accurate and reliable over a range of soil ***,a series of parametric studies confirms its robustness in generalizing *** addition,the results of the comparative study indicate that the optimal LGP model has a better predictive performance than the existing artificial neural network (ANN) model developed earlier by the authors.

关键词： Ground improvement Rolling dynamic compaction (RDC) Linear genetic programming (LGP) Dynamic cone penetrometer (DCP) test

Influence of towing speed on effectiveness of rolling dynamic compaction

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Journal of Rock mechanics and Geotechnical Engineering 2020年第1期12卷 126-134页

作者： brendan T.Scott mark b.jaksa Peter W.mitchell School of Civil Environmental and Mining EngineeringThe University of AdelaideSouth Australia5005Australia Aurecon AdelaideSouth Australia5000Australia

The influence of towing speed on the effectiveness of the 4-sided impact roller using earth pressure cells(EPCs)is *** field trials were undertaken;the first trial used three EPCs placed at varying depths between 0.5 m and 1.5 m with towing speeds of 9-12 km/*** second used three EPCs placed at a uniform depth of 0.8 m,with towing speeds of 5-15 km/*** findings from the two trials confirmed that towing speed influences the pressure imparted to the ground and hence compactive *** paper proposes that the energy imparted to the ground is best described in terms of work done,which is the sum of the change in both potential and kinetic *** practice of using either kinetic energy or gravitational potential energy should be avoided as neither can accurately quantify rolling dynamic compaction(RDC)when towing speed is varied.

关键词： Rolling dynamic compaction(RDC) Optimum towing speed Ground improvement

A Whole Plant Herbaceous Angiosperm from the middle Jurassic of China

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 19-29页

作者： HAN Gang LIU Zhongjian LIU Xueling mAO Limi Frederic m.b. JACQUES WANG Xin Palaeontological Center Bohai UniversityJinzhou 121013LiaoningChina Shenzhen Key Laboratory for Orchid Conservation and Utilization National Orchid Conservation Center of China and Orchid Conservation&Research Center of ShenzhenShenzhen 518114GuangdongChina State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyCASNanjing 210008China Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenCASMengla 666303YunnanChina

In contrast to woody habit with secondary growth, truthful herbaceous habit lacking secondary growth is restricted to angiosperms among seed plants. Although angiosperms might have occurred as early as in the Triassic and herbaceous habit theoretically may have been well adopted by pioneer angiosperms, pre-Cretaceous herbs are missing hitherto, leaving the origin of herbs and evolution of herbaceous angiosperms mysterious. Here we report Juraherba bodae gen. et sp. nov, a whole plant herbaceous angiosperm, from the middle Jurassic （〉164 ma） at Daohugou Village, Inner mongolia, China, a fossil Lagerst^itten that is worldwide famous for various fossil finds. The angiospermous affinity of Juraherba is ensured by its enclosed ovules/seeds. The plant is small but complete, with physically connected hairy root, stem, leaves, and fructifications. The middle Jurassic age recommends Juraherba as the earliest record of herbaceous seed plants, demanding a refresh look at the evolutionary history of angiosperms.

关键词： seed plant Jurassic herbaceous whole plant angiosperm.

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极坐标系下非分裂PmL及时域有限元实现

应用数学和力学 2015年第9期36卷 956-969页

作者：周凤玺曹小林 m.b.贾克萨兰州理工大学土木工程学院兰州730050 阿德莱德大学土木环境与采矿工程学院

在弹性波传播的数值模拟中,吸收边界被广泛应用于截取有限空间进行无限空间问题的分析.完全匹配层(perfect matched layer,PmL)吸收边界较其它吸收边界条件具有更优越的吸收性能,已被成功应用于直角坐标系下的弹性波方程正演模拟.考虑... 详细信息

在弹性波传播的数值模拟中,吸收边界被广泛应用于截取有限空间进行无限空间问题的分析.完全匹配层(perfect matched layer,PmL)吸收边界较其它吸收边界条件具有更优越的吸收性能,已被成功应用于直角坐标系下的弹性波方程正演模拟.考虑极坐标系下二阶弹性波动方程,通过采用辅助函数的方法,提出了一种非分裂格式的完全匹配层吸收边界条件.并且基于Galerkin近似技术,给出了非对称以及轴对称条件下的时域有限元计算格式.通过数值算例分析了该极坐标系下分裂格式的完全匹配层吸收边界的有效性.

关键词：完全匹配层极坐标系吸收边界条件时域有限元

Agro-biodiversity and Traditional Knowledge on Tunisian Coastal Oases

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Journal of Environmental Science and Engineering 2011年第3期5卷 303-308页

作者： m.b. Salah Laboratory of Aridology and Oases Cropping Arid Land Institute Nahal Gabes 6051 Tunisia

The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is composed by various other productions. The present paper is the results of a RAA diagnosis and bibliographic analysis of nearly thirty years of work on oases. The aim of this study is to focus on the plant diversity and the traditions in using different products. The survey revealed the existence of nearly 45 local date palm varieties, about 26 fruit trees, 65 vegetables and divers other species. It also raises nearly 30 uses of dates and date palm.b.-products. This survey shows also that oases inhabitants keep in possessing, for a long time, a knowledge to make ingenious concerning use and conservation of the products and by products of the date palm. This survey has all as much demonstrated the risks from weakening this balance which has long been maintained. Some recommendations to maintain and conserve this system are also presented in this paper.

关键词： Agro biodiversity oases traditional knowledge Tunisia conservation.

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教师的培养与教育理论的学习

华东师范大学学报（教育科学版） 1994年第3期12卷 19-26页

作者： m.b.萨瑟兰任长松

关键词：师范教育教育理论教育学科新教师教育学院师范生教育课程英格兰学生教学实习

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de biología molecular Severo Ochoa(Cbm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting