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排序方式: 共有921条查询结果,搜索用时 15 毫秒
211.
基于解释结构模型的应急机制系统分析   总被引:1,自引:0,他引:1  
运用系统工程理论,对构成突发事件应急机制系统的8个要素进行了定性和定量化处理,建立了应急机制系统的多层递阶解释结构模型。通过模型,证明了要素被分为5个级别,分析了要素之间的纵向和横向关系,确定了信息机制和领导机制要素的基础重要性,为城市应急机制系统的分析、评价和建设提供科学依据。  相似文献   
212.
The industrial sector is usually the largest economy sector for carbon emissions in many countries, which made it the sector with greatest potential for carbon reduction although the process duration might be very long. Studying the potential of industrial emission reduction has great significance in estimating the carbon emission peak of China on the one hand, and adjusting its strategy in international climate change negotiations. By employing the economic accounting method, this article estimates the emission reduction potential of China’s Industrial sector for the period of 2010–2050. It reveals that, taking 2030 as the year when the emission reaches the peak, the total reduction can be 8.38 billion tons (bts) for the period of 2010–2030, with 3.12 bts from structural reduction while 5.26 bts from intensity reduction. Afterwards, reduction will continue with a total amount of 6.59 bts for the period of 2030–2050, where the structural reduction accounts for 2.47 bts, and intensity reduction 4.115 bts. If both industrial and energy consumption structures are improved during the above period, the reduction potential can be even greater, e.g. the emission peak can arrive five years earlier (in the year of 2025) and the peak value can decline by about 8% as compared to the original estimation. Reviewing the trajectory of emission changes in developed countries indicates that the industry sector can contribute to the overall reduction targets through the dual wheels of structural reduction and intensity reduction, even beyond the emission peak. This article concludes with the following policy suggestions. (1) Our estimation on the emission peak of the industrial sector suggests that China should avoid any commitment earlier than 2030 on the timeline of the overall emission peak; (2) the great potential of industrial emission reduction can improve the situation of China in climate change negotiation, where the intensity reduction can serve as an important policy option. (3) Reduction potential can be further enhanced through technology advancement, which requires furthering of market oriented reforms and improvement of institutional design. (4) To secure the reduction effects of the industrial structure adjustment, the balanced development among different regions should be encouraged in order to avoid the reverse adjustment caused by industrial transferring. (5) International cooperation promoting the application and development of industrial emission reduction technologies, including carbon capture, utilization and storage, should be encouraged.  相似文献   
213.
Fuelwood is one of the major sources of energy in the domestic sector across the rural areas,especially in the developing regions across the world.The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area.The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region,thus indicating the livelihood conditions.Since land-use land-cover change is the key driver to the change in resource availability of a region,the present study has tried to analyze the landcover changes over a period 28 years.The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics,which directly affect the resource production.Based on the existing consumption pattern,the total consumption of fuelwood in the watershed ranges fiom a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year.Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.  相似文献   
214.
根据定位系统观测资料,阐述了南亚热带山地常绿森林区、丘陵旱作区和平原水稻区多种土壤的温度变化与气温的关系。观测研究结果表明:低山常绿森林区温度的三维空间差异比丘陵区、平原区大,丘陵区又比平原区大;南亚热带林区的气温、地表温、30cm土温比中亚热带的高,比热带的低:南亚热带林区的谷地气温高于针叶林、混交林和阔叶林,谷地地表温低于针叶林而高于混交林和阔叶林,谷地20m土温低于针叶林、混交林而高于阔叶林;在气温一致的丘陵区栽植植物不同,其地表温、土温略有差异;在平原水稻土区,年气温、地表温、20cm土温差异不大,但30cm以下土温渐显差异;不同地貌单元的气温、地表温和土温的年际差异、年平均温度、各月及0~12~24时的温度动态变化各具特征。根据气温与植物生长的关系,拟把气温>22℃的4~10月称热季、气温<22℃的1~3月及11~12月称作凉季。可因地制宜,根据气温和土温的变化特征与土壤水分和作物生长的关系,采取措施调节温度,以利于作物生长。  相似文献   
215.
根据冀鲁豫交界区(35.0°~36.5°N,113.5°~116.0°E)的地震构造格架与地震活动分布,分析研究了本区的地震活动性,得出了本区地震活动与区域构造运动的牵动作用,并探讨了本区的地震危险性。  相似文献   
216.
给出了火灾下工程结构连续性倒塌的定义,分析了工程结构在火灾作用下的特点,并给出了火灾连续性倒塌判断流程。在介绍目前常用的工程结构抗连续性倒塌分析设计方法的基础上,提出了采用替代路径法中的非线性静力分析方法对建筑结构进行火灾作用下抗连续性倒塌设计的思路。  相似文献   
217.
武汉20世纪90年代暴雨异常的物理环境变化背景探讨   总被引:2,自引:0,他引:2  
根据武汉1951-2000年50年暴雨日数资料,应用Mann-Kendall统计方法对暴雨邓列进行年限突变检验。揭示出武汉暴雨在1979年发生突变,20世纪80年代后暴雨出现频数明显上升,强度增大,90年代达到最大,同时指出武汉20世纪90年代暴雨日数和暴雨量异常的显著特征,着重从西太平洋副热带高压,阻塞高压,太平洋海温等重要物理环境因子的突变出发,探讨造成20世纪90年代武汉暴雨异常的物理变化背景,结果表明,在武汉暴雨异常多的90年代与暴雨异常少的70年代,所对应的大气,海洋环境背景显著不同,90年代北半球500hPa月平均高度场是处于几十年中正异常最大的阶段,西太平洋副热带高压持续偏南,偏强,西伸脊点偏西,东亚中高纬度环流异常,维持稳定的阻塞高压形势,赤道东太平洋海温(SST)出现最大正距平,为近50年来的异常增温时期,厄尔尼诺(ENSO)事件发生频繁。  相似文献   
218.
Research has long recognized the potential benefits of vision communicated at all levels of organizations. Despite this recognition, our understanding of the dynamics surrounding suborganizational visions remains limited. In this paper, we aim to explore these dynamics by investigating the role of organizational structure in the use of suborganizational visions. Although research has begun exploring the implications of structure for vision, it has done so on a limited basis in the context of vertical hierarchies. We take a more comprehensive view, exploring the role of both vertical and horizontal dimensions of structure, with specific interest in the relationship between organizational and suborganizational visions. Our findings suggest not only that structural distance moderates the relationship between organizational and suborganizational visions but also that horizontal distance from the organizational core provides the conditions under which suborganizational units communicate distinct visions that are decoupled from the organizational vision. Furthermore, we find a series of coordinating mechanisms that serve to encourage both the vertical nesting and horizontal complementarity of visions, ensuring alignment, even in the presence of decoupling from the organizational vision. Finally, in describing these findings, we elucidate the role of institutions in both providing content for and ensuring the complementarity of suborganizational visions.  相似文献   
219.
利用波函数展开法结合奇异积分方程技术,研究了部分脱离的埋置半圆形基础与土体的出平面动力相互作用问题。把脱离区看做界面裂纹,将问题归结为一组奇异积分方程。通过数值计算获得了土体和基础中的位移场。利用动应力强度因子描述了粘接区的切应力强度,其结果显示:有缝隙界面基础与土体的动力相互作用呈现明显的低频共振特性。奇异积分方程技术的引入,使得笔者所用方法与已有方法相比更具一般性。研究结果对埋置结构的安全评估与寿命预测具有重要的理论与实际意义。  相似文献   
220.
Abstract

The content of Al, As, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Li, Mg, Mn, Ni, Rb, Se, Sr, and Zn in fruiting bodies of edible mushrooms Calocybe gambosa, Entoloma clypeatum, Entoloma saepium, Xerocomellus chrysenteron, and Amanita rubescens growing in an orchard planted with fruit trees and situated close to a high-grown forest was studied during years 2016–2018. A. rubescens showed the highest potential of the element accumulation with bioconcentration factors of 48.5, 16.2, 7.80, 6.53, 1.75, and 1.68 obtained for Rb, Cd, Cu, Zn, Sr, and Mg, respectively. Both Entoloma species accumulated the elements similarly with bioconcentration factors >1.0 obtained for Rb, Cu, Cd, and Mg. Bioconcentration factors <0.05 were obtained for Al, Cr, Fe, and Pb in all studied species. The contents of beryllium (<0.1?mg/kg dry matter) were always the lowest among the studied elements. The contents of some elements of studied mushroom species significantly fluctuated over the years. Despite the fact that some studied elements (As, Be, Cd, Pb, Ni) are considerably toxic for humans, the pronounced effect on health is not expected if the studied mushroom species are consumed occasionally and do not represent the main component of the diet.  相似文献   
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