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1.
江平盆地侏罗系为一套内陆河湖相沉积,地层结构及岩性变化复杂。可分3个基本层序组,其变化特征,反映了中晚侏罗世江平盆地从扩张到萎缩时期沉积变化规律和沉积体系域变化过程,具有物源丰富、湖水浅、相变快等沉积特点,其层序地层及体系域特征与大陆边缘盆地相比有较大的差异。  相似文献   

2.
It is my profound pleasure to be here today as an honored guest of the opening ceremonies for the Inauguration of Sino-German Joint Group of Paleontology and Geosciences. I stand before you as a member of the National Academy of Sciences of the United States of America, as a Graduate Research Professor of the University of Florida, as an Honorary Professor of Jilin University, as an Honorary Member of the Senckenberg Museum of Natural History, as a Friend of Tuebingen University,  相似文献   

3.
针对风机设备安全运输的道路智能化设计需求,建立了一种综合考虑风电场多维复杂地形环境的道路中心线规划网络模型,在此基础之上设计实现了顾及风电工程建设成本的道路中心线自动规划算法;同时分析计算了风电专题中风机设备的形态结构等参数特征对道路横断面宽度的影响,以实现多要素联合约束的风电场道路优化设计。突破了传统道路设计主要依托CAD辅助制图技术在多维空间整体表达上的局限性,实现了风电场道路的三维实景信息的完备表达。以两种不同地貌类型的风电场为例,验证了方法的实用性和有效性。  相似文献   

4.
在群舞创作中,舞蹈构图就是舞蹈演员与整个舞台空间的静止画面,"静止"是舞蹈构图的表现形式,"流动"是舞蹈调度的表现形式,作为舞蹈构图与构图的必要连接,在营造舞蹈情境和增强形式美上起到了补充作用。舞蹈调度是变换舞蹈构图的一种过程,舞蹈构图是调度过程的某一个停顿和结果。二者相辅相成,不断进行连接和变化,为表现舞蹈作品的主题,交代环境情节和塑造舞蹈形象而发挥其特有的作用。  相似文献   

5.
对空间事物的表达与研究模型主要针对多粒度时空数据本身的描述,而不是描述多粒度时空对象的相关性。多粒度时空对象是一种新的时空对象表达方法,其中时空对象关系的演化过程是一种抽象的复杂的网络的过程。本文在多粒度时空对象表达的基础上,对其演化过程进行形式化定义,提出以时变网络的方法构建初步的关系演化过程模型。通过对基于时间切片的退耕还林演化过程关系的描述与表达,形成动态实时变化的网络模型,从而抽象表达退耕还林过程中的对象关系的演化过程。应用时变网络明确多粒度时空对象关系的演化过程,并对演化过程进行初步的表达和建模,可以使对象关系变化更加清晰化,提高其层次性和效率性,为今后研究多粒度时空对象关系变化规律奠定基础。  相似文献   

6.
本文论述了当前工程地质学界所急待解决的活断层问题,讨论了活断层的定义及其划分标志,提出了活断层工程地质分类原则和评价原则以及具体的评价方法。这对解决一些重大工程项目如核电站、高能加速器装置、大型水力枢纽和火力发电厂等的选址以及城市建设规划布局等都具有重要的工程地质学意义。  相似文献   

7.
The quality of life is considered as the distributed degree of social resources with significance to the urban residents as a whole. There are three features about the study of the quality of life by means of objective method. First, objective methid is based on the government publication of statistics from which the information of social environment influencing people's life can be obtained by systematic analysis. Second, as a result of social policy and planning development, the quality of life studied by objective method can provide scieatific basis for regulating and making policy. Third, the objective method emphasize that the improvement of the quality of life mainly depends on the effort from the government so as to set up a coordinatly developed environment of community.On the basis of relevant data from the 1991 Yearbook of Urban Statirtics of China published by Statistics Press of China, and using spss, the quality of urban life in China is evaluated. Seventy four cities are selected from 467  相似文献   

8.
美国宪法第五修正案规定不动产征收改变了以往封建社会不动产征收为统治阶级服务的目的而转向公共利益。但最初的制度设计随着政府角色定位改变、社会经济发展繁荣等多种因素难以充分应对公共政策制定和实施过程中遇到的各种问题。该文通过分析美国不动产征收权的形成背景及对其产生影响的典型案例,探析美国不动产征收权的形成与演化。结果表明,随着社会经济多元化发展以及公共用途内涵的不断扩展,美国政府通过案例来补充和完善法律在最初界定不动产征收相关条款的概括和不足。政府在行使不动产征收权的时候,虽然部分涉及与经营性用地结合来实现提高本地居民收入、增加就业机会和改善局部市政环境等目标,但如何协调政府行为与公共利益的关键在于建立合理的公共参与制度来反映公众诉求和监督政府行为,以实现个体权益保护的目的。美国不动产征收制度的演化与发展为我国征地制度改革提供了一定的理论借鉴和案例支撑。  相似文献   

9.
1INTRODUCTIONForestlitterwhichisthephysicalmakeuppartofforestecosystempresentsmanyimportantactionsuponecosystem.Howeverifforestlitterisaccumulatedtoexcessitwillproducesomenonnegligiblenegativein-fluencewhichcouldbethecauseofaforestfireortheimpor…  相似文献   

10.
黄河中游黄土高原区河川基流特点及变化分析   总被引:2,自引:0,他引:2  
由于气候变化和人类活动的影响。黄土高原河川基流呈显著下降趋势。对黄河径流量减少产生一定影响。采用日流量过程线切割法计算了河龙区间黄土高原主要支流的基流量。结合地形地貌、水文地质条件,分析了不同地貌类型支流基流的特点,初步分析了影响基流变化的各种因素。认为河龙区间基流变化对黄河水资源影响较大。  相似文献   

11.
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper “How long is the coastline of Britain?” published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method, the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China‘s Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China‘s Mainland, and it does not vary with the changes of series of square grids, the fractal dimensions of the mountains of China‘s Mainland are different with these changes. 2) The fractal dimensions of the mountains of China‘s Mainlandvary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China‘s Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension, and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China‘s Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China‘ s Mainland. The research is helpful to get the more understanding of fractal and fractal dimension, and ensure that the fractal studies would be scientific.  相似文献   

12.
采用钻孔资料对鸡西盆地北部含煤岩系中穆棱组进行了高分辨率层序地层划分,共识别出3个长期、7个中期、58个短期基准面旋回。中、长期基准面旋回由上升、下降2个半旋回构成对称型结构,短期基准面旋回分为对称型和非对称型结构。通过各种级别基准面旋回特征分析,讨论了穆棱组的沉积动力学特征和沉积延续时间。认为穆棱组在鸡西盆地北部条带经历了3次盆地范围内较大规模的湖侵—湖退沉积和7次中等规模、58次小的湖侵—湖退沉积作用,延续时间为5.8 Ma。  相似文献   

13.
《山地科学学报》2020,17(10):2321-2338
In recent decades, research of the Alps, Qinghai-Tibet Plateau, and Cordillera have made great progress in understanding the phenomenon of permafrost. For the most part, this has been made possible due to temperature monitoring. However, the permafrost parameters in an area of more than 2 million square km of the mountainous regions of northeast Asia, for the most part, remain a blank spot in the scientific community. Due to the lack and insufficiency of factual materials, in 2012 the P.I. Melnikov Permafrost Institute began to take temperature measurements in the upper part of the permafrost in the central part of the VerkhoyanKolyma uplands, namely the Suntar-Khayat ridge. The article describes the temperature characteristics of air, surface and rocks of the active layer in the range of heights from 850 to 1821 m, in various landscape and topographic elements. For the observation period from 2012 to 2019, we obtained information on temperatures in the soils of the active layer at depths of 1 m, 3 m, 4 m, and 5 m and also air and surface temperature parameters. The availability of data on automated monitoring of rock temperatures in the active layer and the upper horizons of the layer of annual heat rotations made it possible to substantiate the most typical conditions of the temperature conditions of the permafrost zone of the characterized region. The parameters of permafrost existence and development are in favorable conditions. This is shown in the analysis of temperature data of air, surface and active layer. Soil temperatures in the active layer of annual heat rotations are most clearly represented at a depth of 1 m. Currently, on the territory of the mountain regions of Eastern Siberia, there are no more such sites for monitoring the temperature regime of soils. Information on the permafrost parameters in the region will allow us to begin the process of creating new models or checking existing forecasts and the distribution of the temperature pattern. It will also make it possible to evaluate the response of sensitive and vulnerable frozen soils of mountain regions to climate change.  相似文献   

14.
The economic system of mining city is of typical vulnerability characteristics that can be manifested by its high economic sensitivity and lack of response capacity to the gradual depletion of regional mineral resources. Taking Fuxin City of Liaoning Province as a case, this paper established an economic vulnerability assessment method integrating BP neural network with vulnerability index, then carried out an economic vulnerability assessment of Fuxin during 1989–2006. The results indicate that: 1) Affected by the gradual depletion of regional mineral resources, the economic development of Fuxin had kept high economic sensitivity from 1995 to 2001, and the response capacity to cope with and adapt to the impacts of the perturbation of mineral resources was weak and relatively lag. The evolution of economic vulnerability can be divided into three stages: in 1989–1994, the economic vulnerability of Fuxin City decreased slowly; in 1995–2001, the beginning stage of economic transformation, the economic vulnerability of Fuxin City went up rapidly; in 2002–2006, the economic vulnerability of Fuxin City descended and showed a trend to be stable. 2) The influence of economic sensitivity on Fuxin’s economic vulnerability is more evident than that of response capacity. 3) The decreasing supply of mineral resources and the simple industrial structure are main factors leading to the economic sensitivity of Fuxin. 4) The improvement of economic response capacity of Fuxin has typical characteristics of input-driven growth, and external assistance is of great importance to the rapid improvement of economic response capacity of Fuxin. And 5) the change from the simple industrial structure to diversified one of Fuxin is still unaccomplished, and the contribution of non-coal-based industry to local economic development is relatively limited. Foundation item: Under the auspices of Key Program of National Natural Science Foundation of China (No. 40635030), Knowledge Innovation Programs of the Chinese Academy of Sciences (No. KZCX2-YW-342, No. KZCX2-YW-321)  相似文献   

15.
应用灰色关联分析方法 ,分析了 6个水稻品种 2 1个株型性状对单株产量的影响。结果表明 :单株产量与 2 1个株型性状的关联序依次为 :剑叶厚 >倒二叶厚 >剑叶宽 >倒二叶宽 >倒二叶鞘长 >剑叶鞘长 >倒二叶弦长 >倒三叶宽 >倒三叶厚 >倒三叶鞘长 >剑叶长 >倒二叶长 >倒三叶长 >剑叶弦长 >倒三叶弦长 >倒三叶基夹角 >倒三叶叶开角 >剑叶叶开角 >剑叶基夹角 >倒二叶基夹角 >倒二叶叶开角。  相似文献   

16.
Fractal theory was applied to a preliminary discussion of the fractal character and formation mechanism of the coastline of the bedrock coast of China on the basis of GIS ( Geographical Information System). Some significant conclusions were drawn : ( 1 ) The fractal dimensions of the coastline and linear structures of Liaodong Peninsula are 1.0093 and 1.0246 respectively, those of Shandong Peninsula are 1.019 and 1.021 respectively, etc. (2) The fractal dimensions of coastlines of Liaodong Peninsula, Shandong Peninsula, Zhejiang and Fujian-Guangdong tend to increase with the spatial change from north to south. (3)The regional linear structures( including faults)control the basic trends and fractal dimensions of coastlines as a whole in the regions of the bedrock coast of China : the more the controlling effect of linear structures, the smaller the fractal dimensions of coastlines. (4)The substantial constituents of coast and biologic function both play an important role in affecting the fractal dimensions of coastlines of Liaodong Peninsula,Shandong Peninsula, Zhejiang, Fujian-Guangdong and Taiwan Island.  相似文献   

17.
以东大别地区(115~117.5°E,29.5~32.5°N)岩石圈磁场为基础,通过分解、反演获得岩石圈磁场浅表模型、岩石圈磁场深部模型以及居里等温面埋深分布模型等地下介质磁性结构模型。通过对相关磁异常分布特征的分析发现,东大别地区岩石圈磁场在江淮台隆、郯庐断裂带、下扬子台坳构造地区呈正异常条带或团块分布,在北淮阳褶皱带则是以一条EW向巨大负异常通过。对比岩石圈磁场与浅表磁场发现区内几条隐伏断层的走向及切割深度;岩石圈深部磁场在一定程度上反映区内岩石圈基底的分布及构成;居里面埋深可揭示区内岩浆活动的分布情况。  相似文献   

18.
陈蔡群原岩的主体形成于大洋岛弧环境,由拉斑玄武岩和同源辉长岩,碳酸盐岩和浊流沉积的泥砂质碎屑岩组成;经受了中压角闪岩相区域动力—热流变质作用和多期褶皱变形;岩石地球化学和同位素年代资料表明,中国东南的威尔逊旋回在中元古晚期便已开始,即那时于扬子古陆与华夏地块之间存在一大洋盆地,洋壳上可能存在拉张期残留的花岗质陆壳碎块。中元古晚期开始了洋壳消减作用及其有关的火山—沉积作用,新元古晚期陈蔡大洋岛弧地体与双溪坞陆弧地体拼贴、碰撞,壳体间的聚合作用触发了陈蔡群岩石的变质、变形。  相似文献   

19.
冷库系统变工况性能的理论分析   总被引:1,自引:0,他引:1  
对氨冷库蒸汽压缩制冷系统进行理论分析。通过改变环境温度,改变蒸发器和冷凝器压力降,建模计算了冷库系统的损失、效率和制冷系数COP,结果表明,系统各设备的损失随着环境温度升高而变化,系统设备性能随着压力降升高而变化。认为减少蒸发器和冷凝器的传热温差,减少压缩机内不可逆损失,减少蒸发器的压力降等可以提高系统性能。  相似文献   

20.
昆仑山口西8.1级地震易县台潮汐形变图像浅析   总被引:5,自引:2,他引:3  
用易县地震台潮汐形变观测资料分析了青海昆仑山口西8.1级地震时同步出现的同震阶跃的特征。可以看出,DSQ型水管仪、VS型垂直摆、TJ-2C型体应变仪的同震阶跃呈负值变化,而SS-Y型伸缩仪之EW分量和NE分量呈正值变化。  相似文献   

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