检索结果-南通市图书馆

Strength of massive to moderately jointed hard rock masses

journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 562-575页

作者： R.P.Bewick P.K.Kaiser f.Amann Golder Associates Ltd. 33 Mackenzie StreetSudburyOntarioP3C 4Y1Canada Laurentian University 935 Ramsey Lake RdSudburyP3E 2C6Canada RWTH Aachen Lochnerstrasse Aachen4-20D-52064Germany

The Hoek-Brown (HB) failure criterion and the geological strength index (GSI) were developed for the estimation of rock mass strength in jointed and blocky ground where rock mass failure is dominated by sliding along open joints and rotation of rock blocks. In massive, veined and moderately jointed rock in which rock blocks cannot form without failure of intact rock, the approach to obtain HB parameters must be modified. Typical situations when these modifications are required include the design of pillars, excavation and cavern stability, strainburst potential assessment, and tunnel support in deep underground conditions (around σ1/σci > 0.15, where σ1 is the major principal compressive stress and σci is the unconfined compressive strength of the homogeneous rock) in hard brittle rocks with GSI ≥ 65. In this article, the strength of massive to moderately jointed hard rock masses is investigated, and an approach is presented to estimate the rock mass strength envelope using laboratory data from uniaxial and triaxial compressive strength tests without reliance on the HB-GSI equations. The data from tests on specimens obtained from massive to moderately jointed heterogeneous (veined) rock masses are used to obtain the rock and rock mass strengths at confining stress ranges that are relevant for deep tunnelling and mining;and a methodology is presented for this purpose from laboratory data alone. By directly obtaining the equivalent HB rock mass strength envelope for massive to moderately jointed rock from laboratory tests, the HB-GSI rock mass strength estimation approach is complemented for conditions where the GSIequations are not applicable. Guidance is also provided on how to apply the proposed approach when laboratory test data are not or not yet available.

关键词： Brittle rock Uniaxial compressive strength(UCS) Geological strength index(GSI) Massive to moderately jointed rock masses

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

THE TRANSfER Of LOW fREQUENCY SIGNAL BY THE NONNEUTRAL ELECTRON PLASMA IN EV DEVICE

引用

Science China Chemistry 1992年第10期35卷 1201-1209页

作者：郑少白 j.H.MALMBERG C.f.DRISCOLL Institute of Physics Academia Sinica Beijing 100080 PRC Department of Physics UCSD San Diago V.S.A

The transfer of low frequency signal by the nonneutral electron plasma in EV deviceis investigated in this *** experiment results are consistent with approximate theoryand numerical calculation of rigorous theory,showing that the transfer is due to the wholemovement of the electron *** work provides a practical method for measuring thetotal nonneutral electron plasma energy in similar EV device without destroying the plasmaState.

关键词： nonneutral electron plasma low frequency modulation

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

ZC型液压缸整体联解法

引用

塑性工程学报 2001年第1期8卷 66-69页

作者：赵长财燕山大学 066004

本文提出了 ZC型液压缸的整体联解法。该计算方法不受βL的限制 ,适用范围广 ,完善了 ZC型液压缸的计算理论 ,进行了有限元对比验算。

关键词： ZC型液压缸整体联解法弹性法兰有限元

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

Introduction to the special issue on “COVID-19”

引用

Geoscience frontiers 2022年第6期13卷 208-209页

作者： Luis f.O.Silva Weijun Li Teresa Moreno Department of Civil and Environmental Universidad de la CostaCUC Department of Atmospheric Sciences School of Earth SciencesZhejiang University Institute for Environmental Assessment and Water Research Consejo Superior de Investigaciones Científicas

COVID-19 pandemic is wreaking havoc and bringing the whole world into a standstill in an unprecedented fashion. joint efforts from multiple sectors to address the various aspects of environment and public health through usage of green technologies have become essential. The application of cleaner and effective technologies can be expanded to management and control, pollution mitigation and valorization of waste. In this Special Issue of Geoscience frontiers, we present contributions addressing the interactions of COVID-19 in relation to environment and human health.

关键词： bringing expanded COV

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

Modeling of a Photovoltaic Module Considering the Solar Energy Available from Horizontal Surfaces over Kuwait Area

引用

journal of Electronic Science and Technology 2012年第2期10卷 173-180页

作者： f. Q. Al-Enezi j. K. Sykulski the School of Electronics and Computer Science University of Southampton

The paper identifies and analyzes the geographical and temporal variability of solar energy in Kuwait. The fundamental solar trigonometric model has been modified to estimate daily and hourly solar radiation on horizontal surfaces on the basis of the more readily available meteorological data. The results demonstrate that Kuwait has an abundance of solar energy capability. An overview of the production and consumption of electrical energy, installed capacity, and peak loads in Kuwait is also presented. finally, it is shown how the power produced from the photovoitaic （PV） cells depends on the solar radiation. The proposed PV module is made up of a combination of series and parallel cells to increase power, while the IoV characteristic and output power of the module each month may be obtained from the model.

关键词： Extra-terrestrial insolation hour angle meteorological data peak load photovoltaic module solar radiation solar time.

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

中国SONG项目高分辨光谱仪与高精度恒星震动视向速度测量

引用

光谱学与光谱分析 2018年第2期38卷 621-626页

作者：闫正洲邓李才张春光罗常青 Grundahl f 胡中文季杭馨王家宁徐明明戴松星 Andersen M f 王坤田健峰中国科学院国家天文台北京100012 中国科学院大学北京100049 Aarhus University AarhusDanmark 中国科学院国家天文台南京天文光学与技术研究所江苏南京210042 西华师范大学物理与空间学院四川南充817000

中国SONG项目(Stellar Observations Network Group)是中国天文界参与的一个国际合作的天文学研究计划。其核心是利用高分辩光谱仪获取恒星的时序光谱。光谱仪的分辨率根据科学目标的要求,用不同的狭缝宽度实现R=60 000~120 000。利用... 详细信息

中国SONG项目(Stellar Observations Network Group)是中国天文界参与的一个国际合作的天文学研究计划。其核心是利用高分辩光谱仪获取恒星的时序光谱。光谱仪的分辨率根据科学目标的要求,用不同的狭缝宽度实现R=60 000~120 000。利用碘蒸汽发射线定标的方法,实现高达1m·s-1的视向速度测量精度,以此测量恒星表面由于恒星震动产生的多普勒运动,并实现项目的科学目标。SONG光谱仪是项目的核心设备,将介绍光谱仪的性能和天体物理应用的参数,并给出实际测量结果。作为一个测量恒星表面多普勒运动时序数据的仪器,整个系统的长期稳定性是项目取得成功的关键,在此也将展示仪器稳定性方面的工作。

关键词：高分辩光谱仪高精度视向速度测量

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

Pathogenic Variation and Occurrence of Multiple Resistance-Breaking <i>Rice yellow mottle virus</i>Strains in Tanzania

引用

American journal of Plant Sciences 2017年第8期8卷 1820-1841页

作者： judith Hubert Herman j. f. Lyimo Ashura Luzi-Kihupi Department of Crop Science and Horticulture Sokoine University of Agriculture Morogoro Tanzania

Rice yellow mottle virus (RYMV) is a major biotic constraint for rice production in Africa. The resistance-breaking ability of Tanzanian RYMV strains and phylotypes (S4lm (Tz526), S4lv (Tz516), S4ug (Tz508), S5 (Tz429, Tz445), S6c (Tz486) and S6w (Tz539)) were tested by inoculating rice cultivars with RYMV1 resistant alleles (Gigante (rymv1-2), Tog12387 (rymv1-3), Tog5681 (rymv1-3), Tog5438 (rymv1-4), Tog5672 (rymv1-4+rymv2) and Tog5674 (rymv 1-5)) in a screen house. The results revealed multiple resistance-breaking strains and phylotypes on resistant cultivars Gigante, Tog12387, Tog5438 and Tog5681. However, the resistance breakdown was highly variable depending on the strain used, and disease severity ranged from 11% - 75.3%. The virulence potential of RYMV phylotype S4lm (Tz526) was similar to phylotype S6w (Tz539). The impact of strains and phylotypes on yield and its components in rice cultivars revealed highly significant differences (P ≤ 0.001). The lowest percent plant height reduction (2.8%), number of tillers per plant (2.5%), 1000 grain weight (2.7%), spikelet sterility (3.5%) and yield (5%) was recorded in rice cultivar Gigante inoculated with RYMV phylotype S6c (Tz486). Phylotype S6c (Tz486) despite being less virulent compared to other strains, its virus titer in rice cultivar Gigante (1.833) was higher than S5 (Tz429, Tz445) inoculated on Tog5674 (0.171, 0.207) and S6w (Tz539) inoculated on Tog5681 (0.283). The resistant-breaking strain S5 (Tz445) multiplied in resistant rice cultivar Tog5674 without inducing visible symptoms but showed positive reaction to ELISA with low virus titer. The strain S5 overcame wide range of resistant alleles including rymv1-2, rymv1-3, rymv1-4 and rymv1-5 resistance, with exception of rymv1-4 + rymv2. The current results gave a new perspective for future identification of resistance-breaking mutations through sequencing of the RYMV genome in infected rice cultivars and mutagenesis of an infectious viral clone useful for

关键词： Pathogenic Variation Virulence Multiple Resistance-Breaking RYMV Strains Yield Losses Tanzania

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

免修、半免修复层防火林带阻火机理研究

引用

林业科学研究 2007年第6期20卷 859-863页

作者：洪长福福建省长泰岩溪国有林场福建长泰363902

利用山沟、小山脊呈"鸡爪型"分布的特点,在沟边和小山脊采取不同措施营建高阻火效能、低维护成本的免修、半免修复层防火林带,并研究其阻火机理。对火环境主要因子调查分析表明:免修复层防火林带衰减光照能力强,降温保湿效果好,挡风能力... 详细信息

利用山沟、小山脊呈"鸡爪型"分布的特点,在沟边和小山脊采取不同措施营建高阻火效能、低维护成本的免修、半免修复层防火林带,并研究其阻火机理。对火环境主要因子调查分析表明:免修复层防火林带衰减光照能力强,降温保湿效果好,挡风能力强,乔木、灌木、草本层和枯枝落叶层以及土壤的含水率高,阻火效果最好;半免修复层防火林带阻火效果次之,山脊单层防火林带阻火效果最差。因此,应充分利用沟边残存阔叶林和沟边小山脊特有的湿润环境,营建免修、半免修复层新型防火林带,并对现有单层防火林带进行改造。

关键词：免修、半免修复层防火林带阻火机理生物阻火

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

多个激活度量相结合的小波图像融合方法

引用

光电工程 2009年第5期36卷 62-65页

作者：龚昌来嘉应学院电子信息工程学院广东梅州514015

在小波分解的基础上,将小波系数绝对值与局部能量二个激活度量相结合,提出了一种新的小波图像融合算法。根据二幅源图像在同一分解层及同一方向上相同位置的小波系数绝对值之间和局部能量之间出现的4种不同组态,采取选择和加权平均方法... 详细信息

在小波分解的基础上,将小波系数绝对值与局部能量二个激活度量相结合,提出了一种新的小波图像融合算法。根据二幅源图像在同一分解层及同一方向上相同位置的小波系数绝对值之间和局部能量之间出现的4种不同组态,采取选择和加权平均方法确定融合图像的小波系数。实验结果表明新算法具有较好的融合效果。

关键词：图像融合小波变换局部能量小波系数绝对值

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

Virtual Water Trade as a Strategy to Water Resource Management in Iran

引用

journal of Water Resource and Protection 2014年第2期6卷 141-148页

作者： f. Mohammadi-Kanigolzar j. Daneshvar Ameri N. Motee Department of Agricultural Economics and Development University of Tehran Tehran Iran

Agriculture has historically played a central role in the economy, life and culture of the Iranian population. Nowadays, this sector is facing the reality that its natural fresh water resources become fully utilized. Considering the climate conditions and limitation of using new water resources and the necessity of increasing agricultural product as a result of population growth, there is a general doubt about Iran’s ability to maintain this level of production amid the mounting water challenges, among other obstacles. Therefore, the evaluation of virtual water and water footprint can provide new indicators for informing water policy decisions. So, in order to study the situation at the national level, we estimated virtual water consumption in term of virtual water theory as well water footprint in agriculture sector of Iran. Data from 2001-2008 were used to account for yearly. The results of this study show that Iran has water import dependency and also net water import is 12.7 billion m3 averages. So Iran country saved 12.7 billion m3 from their domestic water resource for utilization in other sectors. finally, it should be concluded that virtual water trade as a policy measure to water resources management will be provided to a great extent in order to reach both significant water saving and environmental sustainability.

关键词： Virtual Water footprint Water Resource Management Environmental Iran

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

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

在线全文

在线全文

在线全文

在线全文

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

在线全文

在线全文

在线全文

在线全文

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：