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1.
本文采用对比分析与归纳分析法,在明确全民所有自然资源资产管理考核评价机制定位的基础上,充分借鉴和参考现有相关考核评价制度的设计思路,围绕“考核谁、谁来考、怎么考、考什么、结果怎么定、结果怎么用”等关键问题,从考核评价对象和实施主体、考核评价方式和实施、考核评价结果应用、考核评价内容和指标体系构建、考核评价结果评定方法等方面,提出构建全民所有自然资源资产管理考核评价机制和方法的思路,为推进生态文明建设和自然资源资产产权制度改革提供支撑。  相似文献   

2.
不规则煤层开采容易引发顶板应力集中、矿压显现异常等问题,为探究变面长采场顶板破断规律与结构演化特征,针对工作面斜长由小变大的突变型采场不同开采阶段的几何特征与力学成因,运用小挠度薄板弯曲理论依次建立并解析4种边界条件的顶板结构模型。根据变面长采场顶板矿压分区显现特征,采用MATLAB与FLAC3D数值模拟方法分析顶板破断规律与宏观力学响应。通过系统分析与总结归纳,构建了变长工作面“三场三区三结构”的覆岩结构传递演化模式,提出了“两场两规律”的顶板分区破断效应。并通过典型工程案例的矿压实测进行应用验证。结果表明:变面长采场分为小面采场、变面采场和大面采场,小面采场顶板为缓压型结构,发生的是传统“O-X”形破断;变面采场顶板为突变型结构,顶板断裂产生的延长形与漂移形“O-X”破断裂隙与大面采场增压型结构顶板的裂纹发育特征较为相似,故将二者整合为全大面采场;全大面采场顶板发生的是“X-O”形破断,裂纹继续发展产生延长形破断,形成“两场两规律”的顶板破断理论。研究结论为探明变面长采场的覆岩运移本质,加强深部复杂煤层赋存条件下的顶板灾害防控提供了重要依据。  相似文献   

3.
基于SPA的喀斯特地区水安全评价——以贵州省为例   总被引:6,自引:5,他引:1  
苏印  官冬杰  苏维词 《中国岩溶》2015,34(6):560-569
根据目前公认的水安全内涵,将水安全分为三个子系统。水资源子系统、水环境子系统和水灾害子系统。三者相互联系、相互作用,形成了复杂、时变的水安全系统。基于水安全的基本原理和喀斯特区域特有的水循环机理,依据 “驱动力(D)—压力(P)—状态(S)—影响(I)—响应(R)”模型建立了贵州省喀斯特区域水安全评价指标体系。基于集对分析理论,引入能够体现系统确定性和不确定性的同异反联系度计算公式,建立了城市水安全的评价模型。将集对分析法运用到水安全的评价中, 可以先通过计算评价样本与评价指标之间的联系度对样本作初步的排序, 再对样本作进一步的同一、差异、对立的集对分析,以判断出评价样本的等级。研究结果表明:(1)在水资源安全状态方面,贵州省9个州市中4个处于安全状态,2个处于基本安全状态,2个处于不安全状态,1个处于危机状态;(2)在水环境安全状态方面,2个处于安全状态,4个处于基本安全,3个处于不安全;(3)在水灾害安全状态方面,1个处于非常安全,4个处于安全,1个处于基本安全,2个处于不安全,1个处于危机;(4)在水安全综合状态下,有3个处于安全状态,有4个处于基本安全状态,有2个处于不安全状态,没有处于非常安全和危机状态。   相似文献   

4.
James Anderson 《Geoforum》1980,11(2):171-178
Geography has been traditionally concerned with “Nature”, “Place” and “Space”, and yet has failed to make profound contributions to their study and analysis because the discipline lacks a consistent theory of society and its relationships with “Nature”. This paper examines some of the reasons for this deficiency and proposes that Historical Materialism provides the best framework for resolving this problem.  相似文献   

5.
Kiribati, Tuvalu, Marshall Islands, the Maldives and other small island developing states in the Pacific are often incorrectly called “sinking islands.” With their highest points just a few meters above sea level, they face adverse impacts from climate change and especially sea level rise, which can cause them to disappear entirely or make their territory uninhabitable. After rather frustrating negotiations on other fora, the representatives of those states asked the UN Security Council to deal with their perilous situation in 2007. On the one hand, some countries used scientific argumentation to justify the introduction of this new security agenda. On the other hand, prominent UNSC members such as China and Russia, supported mainly by rapidly developing large countries, rejected it, arguing that the Security Council did not have the expertise to solve environmental problems. Since then the islands have echoed their plight to the UNSC in 2011 and 2015. This paper determines what roles individual countries ascribe to “experts” and “science” during UNSC negotiations. It examines how the authority of “experts” was exploited, which allowed certain countries to strike the issue of those islands from the UNSC agenda by calling for a more “scientific approach,” while others used “science” to widen the concept of security. The analysis of empirical data confirms the theory of Berling's three modalities when referring to science. Those modalities can be further extended by Foucault's conception of “will to truth” as a method of exclusion, and Chandler's theory of “empire in denial” as a way of evading responsibility, while maintaining power.  相似文献   

6.
The capacity of numerical methods is very large. It covers complex geomtries, nonlinear material laws, excavating phases in tunnelling. The finite element methods has been developed from continuum theory. Hence, the method is readily applicable for materials like steel, salt-rock, fluids, sands, clays but less suitable for concrete, jointed rocks, discontinua. Real failure modes during excavation in rock are scarcely covered by the finite element approach but satisfactory results are obtained if stresses and deformations under working loads are of interest. Problems arising when results obtained by sophisticated analysis have to be interpreted by engineers not familiar with the method are discussed (“black box”).  相似文献   

7.
In this study, a geotechnical model has been used to analyze the stability of a discontinuous rock slope. The main idea behind block theory is that it disregards many different combinations of discontinuities and directly identifies and considers critical rock blocks known as “key blocks”. The rock slope used as a case study herein is situated in the sixth phase of the gas flare site of the South Pars Gas Complex, Assalouyeh, Iran. In order to analyze the stability of discontinuous rock slopes, geotechnical modeling which was divided into geometrical sub-modeling and mechanical sub-modeling has been utilized. This model has been established upon the KGM (key-group method) algorithm which was based on the limit equilibrium method and block theory and prepared and coded by the Mathematica software. According to the results of the stability analysis, the analyzed slope was determined to be in the category of “needs attention,” and the security level, calculated through the FORM (first-order reliability method) analysis, was estimated to be 1.16. In order to verify the model, the results obtained from the model were compared with those of the UDEC software, which is a numerical method based on distinct components. As a conclusion, it was determined that the results of the model agreed well with those of the numerical method.  相似文献   

8.
The occurrence of water in natural opaline silicas has been studied by differential thermal analysis, thermogravimetric analysis, infra‐red analysis and nuclear magnetic resonance. The results show that in the “crystalline” opals studied, some 90 per cent or more of the total water is physically adsorbed whereas in “amorphous” opals, at least 20 per cent but perhaps much more of the total water is held as hydroxyl groups chemically bonded to the silica surface. The rate of water loss on heating is also different, being chiefly controlled by the pore structure in “crystalline” opals but to a significant extent by the surface structure in “amorphous”.  相似文献   

9.
A basic, sinusoidal solution to the linearized equations of equilibrium for compressible, elastic materials provides solutions to several problems of folding of multilayers. Theoretical wavelengths are comparable to those predicted by Ramberg, using viscosity theory, and to those predicted by elementary folding theory. The linearized analysis of buckling of a single, stiff, elastic layer, either isolated or within a soft medium, suggests that wavelengths computed with elementary beam theory are remarkably similar to those computed with the linearized theory for wavelength-to-thickness ratios greater than about five. This is half the limit of ten normally assumed for use of the elementary theory.The theory and experiments with deep beams of rubber or gelatin indicate that thick, homogeneous layers folded with short wavelengths assume internal forms strikingly similar to those of the ideal concentric fold. Thus, mechanical layering clearly is not required to produce concentric-like forms.Further, the theory suggests that “arc and cusp” structure, or “pinches”, at edges of deep beams as well as chevron-like forms in single or multiple stiff layers are a result of a peculiar, plastic-like behavior of elastic materials subjected to high normal stresses parallel to layering. In a sense, the elastic material “yields” to form the hinge of the chevron fold, although the strain vanishes if the stresses are released. Accordingly, it may be impossible to distinguish chevron forms produced in elastic-plastic materials, such as cardboard or aluminum and perhaps some rock, from chevron forms produced in purely elastic materials, such as rubber.Analysis of the theory shows that, just as high axial stresses make straight, shortened multilayers the unstable form and sinusoidal waves the stable form, stresses induced by sinusoidal displacements of the multilayer make the sinusoidal waveform unstable and concentric-like waves the stable form. Thus, concentric-like folds appear to be typical of folded multilayers according to our analysis. Further, where the layers have short wavelengths in the cores of the concentric-like folds, the stiff layers “yield” elastically at hinges and straighten in limbs. Thus the concentric-like pattern is replaced by chevron folds as the multilayer is shortened. In this way we can understand the sequence of events from uniform shortening, to sinusoidal folding, to concentric-like folding, to chevron folding in multilayers composed of elastic materials.  相似文献   

10.
沙漠沙丘污水处理系统:原理、方法和效果   总被引:1,自引:0,他引:1  
“沙漠沙丘系统(DDS)”是以地球化学工程学原理为指导的特殊水处理系统,它利用沙漠沙作为滤料,通过“机械过滤”、“化学作用”和“生物作用”净化污染水,一方面可使沙丘变得湿润而不再移动,以固定移动沙漠;另一方面又能净化污染水,最终起到“以害克害、固沙治水、一举多得”的良好综合生态环境效应。DDS是绿色的水处理系统,所需的原料和生成物都属于自然界存在的物质,无二次污染的发生。在DDS设计中,要注意的主要因素应包括:滤料的种类、湿干时间比、微生物培养方式、滤料层厚度、进水水质、时间、温度和pH等。DDS可以把官厅水库水由V类和超V类处理成2~3类水,从而恢复官厅水库的饮用水功能。  相似文献   

11.
Hot springs are natural exposed points of the hydrothermal system. The hydro-geochemistry of hot springs can be used to interpret the formation of the hydrothermal system; and the 14C dating can be used to evaluate the renewability of the hydrothermal system. The hot springs exposed from fault zones in western Guangdong are classified as granite fissure water and clastic rock fissure water, which are sampled and tested. The results of water chemistry analysis show that hot spring water is mainly HCO3-Na type in the beginning, while the mixing of seawater leads to the increase of Cl-. Hydrogen and oxygen isotopes indicate that these hot springs mainly come from atmospheric precipitation, and water-rock interactions produce oxygen isotope exchange reactions, where a significant “oxygen drift” phenomenon can be observed. The relationship between δ13C and HCO3- indicates that there is a deep source of CO2 “dead carbon” in hot spring water. This systematic error is not considered in the existing 14C dating correction models. The 14C age of the deep source “dead carbon” correction proposed in this paper is close to the 14C age of the reverse chemical simulation correction, the Gonfiantinie model, and the Mook model. The deep source “dead carbon” correction method can improve the systematic error. Therefore, the 14C age corrected by the deep source “dead carbon” may be more representative in terms of the actual age of geothermal water.  相似文献   

12.
本文以兰州黄土为研究对象,开展了不同加载速率条件下的K0压缩试验,并结合试验结果和“等速线理论”研究了震动荷载作用下黄土的动力学响应及其影响因素。研究结果显示,随着加载速率的升高,回弹系数(a)、塑性压缩系数(b)、前期固结压力(σp)以及内变量参考时间(τp)均会产生显著变化。其中,加载速率的升高对内变量参考时间影响最为剧烈,而加载速率对黏塑性应变速率参数(c)的影响可以忽略。通过对比震动荷载作用下土体应变发展的计算和实测结果表明,基于加载速率较快的试验结果获取的模型参数,其理论预测精度较高。在计算动力学问题中,σp的量值较静力条件下获取的参数要小2~3个数量级,这是使用该模型计算动力问题与静力问题的最大不同。进一步的计算分析表明,震动荷载作用下的动应变幅值与回弹系数正相关,而(b-a)/c和应力比(震动荷载的平均值与前期固结压力之比)正比于动荷载初期作用下发生的塑性应变(“残余应变”)。因而,在评价土体动荷载作用下的“残余应变”时,应综合考虑各力学参数和应力状态的影响。  相似文献   

13.
初论地质信息有序系列   总被引:3,自引:0,他引:3  
信息有序系列(IOS)是笔者提出的一个新概念,是指具有非随机性定义的信息、非周期性、存在于大量无序中的有序部分特征的有序性。IOS的理论是应用基于较少假设的、较为简单的数字或几何模式去研究地质体客观存在的复杂性,减少类似概率分布、周期性、平稳性、遍历理论等假设要求。IOS中的一组现象,表面上看类似于周期,但被广义地定义,它们不能被谱分析和统计分析发现。“系列”一词用以与“模型”相区别,其特点是仅在有限范围和短时间内存在,是不平稳和遍历的。“有序”一词是强调在混沌中存在的有序部分,可应用于预测目的。所以,IOS是有序性中一部分。大地震、热点、超大型矿床、节理等时空分布表明了IOS的客观存在。  相似文献   

14.
Stochastic process theory involves integrals of measurable functions over probability measure spaces. One of these is the ensemble space, Ω, whose members are sample functions on Euclidean spaceR k and the other isR k itself. What geostatisticians call the “theory of regionalized variables” is said to based on stochastic theory. A recent paper inMathematical Geology proclaims a distinction between “probabilistic” and “deterministic” geostatistics. The former is said to rely on “ensemble integrals” over Ω and the latter on “spatial integrals” overR k. This study shows that the proposed distinction rests on an arbitrary choice between two estimators for the covariance of a stochastic process; neither is an ensemble integral, both are spatial integrals, and both are Kolmogorov inconsistent. The “deterministic” estimator is identical with that of classical bivariate least-squares regression in which “spatial structure” is of no consequence. This study shows that both stochastic models are suboptimal approximations to the unique nonstationary classical statistical multivariate regression model generated by each sample pattern. The stochastic process model and its “spatial continuity measures,” thus, appear as questionable mathematical embellishments on suboptimal estimates, correspondence with geomorphic reality is tenuous, and estimates are biased and distorted. Various related misconceptions in the paper are also discussed.  相似文献   

15.
Hot springs are natural exposed points of the hydrothermal system. The hydrogeochemistry of hot springs can be used to interpret the formation of the hydrothermal system; and the ~(14)C dating can be used to evaluate the renewability of the hydrothermal system. The hot springs exposed from fault zones in western Guangdong are classified as granite fissure water and clastic rock fissure water, which are sampled and tested. The results of water chemistry analysis show that hot spring water is mainly HCO_3-Na type in the beginning, while the mixing of seawater leads to the increase of Cl~-. Hydrogen and oxygen isotopes indicate that these hot springs mainly come from atmospheric precipitation, and water-rock interactions produce oxygen isotope exchange reactions, where a significant "oxygen drift" phenomenon can be observed. The relationship between δ~(13)C and HCO_3~- indicates that there is a deep source of CO_2 "dead carbon" in hot spring water. This systematic error is not considered in the existing ~(14)C dating correction models. The ~(14)C age of the deep source "dead carbon" correction proposed in this paper is close to the ~(14)C age of the reverse chemical simulation correction, the Gonfiantinie model, and the Mook model. The deep source "dead carbon" correction method can improve the systematic error. Therefore, the ~(14)C age corrected by the deep source "dead carbon" may be more representative in terms of the actual age of geothermal water.  相似文献   

16.
大洋多金属结核资源评价的基本理论与方法   总被引:2,自引:0,他引:2  
根据大量工作实践和研究,系统扼要地介绍了大洋多金属结核资源评价的基本概念、理论基础、评价方法及国内外概况;论述了多元统计分析 (聚类分析、因子分析、趋势面分析 )、地质统计学 (克立格法 )、神经元网络分析进行多金属结核资源评价的方法原理;以及实现矿区边界指标-资源量-面积动态分析的《大洋多金属结核资源动态评价系统》软件开发简介.  相似文献   

17.
“地质学基础”是各高校地质学专业开设的第一门导论性课程,对于培养专业兴趣、构建专业知识体系是至关重要的,也是地质学专业课程体系中融入课程思政内容最理想的一门课程。“四个自信”是指“中国特色社会主义道路自信、理论自信、制度自信、文化自信”。将“四个自信”思政元素融入“地质学基础”课程是地质学专业课程思政建设中回答“培养什么人、怎样培养人、为谁培养人”这一教育根本问题的重要举措。论文从地质学专业的角度出发,详细论述了“地质学基础”课程融入“四个自信”思政元素的必要性、天然优势和提取“四个自信”思政元素的途径及相关内容。  相似文献   

18.
西准噶尔吾尔喀什尔山与额敏盆地间的"盆"–"山"耦合关系清楚,盆地边界平行于造山带呈狭长带状展布。"山"区为志留系–石炭系海相陆源碎屑岩-火山岩沉积组合,"盆"区为二叠系陆相磨拉石与新近系红色砂砾岩及第四系河流阶地堆积,具有典型的海相-陆相双层结构。盆缘被巴尔雷克前陆冲断带围限,"山"区发育铲式逆冲断层与蛇头构造、叠瓦扇构造等逆冲推覆构造。表明该"盆"–"山"组合为一典型的前陆盆地系统。额敏前陆盆地形成于早二叠世,属后期冲断变形影响较弱、早期前陆盆地结构特征较明显的"早衰型"前陆盆地。这一成果为额敏盆地乃至西准噶尔盆地分析、构造演化、沉积作用、"盆"–"山"耦合等研究提供了重要信息。  相似文献   

19.
In a conventional approach, the mechanical behaviour of a structure subjected to seismic or blast waves is treated separately from its surroundings, and in many cases, the dynamic coupling effect between multiple structures and the waves propagating in the ground is disregarded. However, if many structures are built densely in a developed urban area, this dynamic interaction may not become negligible. The first purpose of this contribution is to briefly show the effect of multiple interactions between waves and surface buildings in a town. The analysis is based on a recently developed, fully coupled, rigorous mathematical study, and for simplicity, each building in the town is represented by a rigid foundation, a mass at the top and an elastic spring that connects the foundation and mass. The buildings stand at regular spatial intervals on a linear elastic half-space and are subjected to two-dimensional anti-plane vibrations. It is found that the buildings in this model significantly interact with each other through the elastic ground, and the resonant (eigen) frequencies of the collective system (buildings or town) become lower than that of a single building with the same rigid foundation. This phenomenon may be called the “town effect” or “city effect.” Then, second, it is shown that the actual, unique structural damage pattern caused by the 1976 Friuli, Italy, earthquake may better be explained by this “town effect,” rather than by investigating the seismic performance of each damaged building individually. The results suggest that it may also be possible to evaluate the physical characteristics of incident seismic/blast waves “inversely” from the damage patterns induced to structures by the waves.  相似文献   

20.
Indigenous peoples have been enrolled in climate change research for decades, participating in data-gathering, as writing collaborators, and serving as the symbolic “canary in the coal mine” for public outreach and policy-making. They have indeed experienced some of the most rapid environmental changes, but rather than emphasize their vulnerabilities, we argue their expertise is narrowly understood in formulating knowledge; the research on climate change has a limited understanding of what it might mean to be inter- or trans-disciplinary because research is formulated exclusively through the assumptions of Enlightenment thought, without sufficiently engaging non-Western subjectivities. Qualitative social sciences and “Indigenous methodologies” can be used to better achieve trans-disciplinarity; in this article we re-tell a story told by Native elders from tribes across Alaska about the “man on the moon.” While literally referring to the US moon landing, elders invoke this story when addressing climate change: it teaches the ethics of the human-nature relationship, developed from a “more-than-human” (or “posthuman”) philosophy. Our data comes from participant-observation and oral history; we draw upon poststructuralist theory, and frame our analysis through the literatures of critical geography, science studies, and American Indian studies. To ensure that Indigenous peoples are not used as props in Western policy agendas, researchers must engage with non-Enlightenment intellectual traditions. More than being a source of data or a symbol of humanity’s ruin, Indigenous wisdom can productively inform sustainable policy agendas to adapt to climate change. What can be learned, for example, is a more-than-human ethics of place and space.  相似文献   

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