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1.
现场总线是用于自动化系统最底层的现场设备或仪表互联的通信网络。CAN是现场总线中的一种，具有较高的性能价格比和较强的实时处理能力。文章以采用CAN总线的通讯网络结构的校园消费系统为例，介绍在CAN总线通信中如何采用基于多线程的通信程序实现实时的接收、处理和发送数据的功能，对多个线程之问的协作关系进行了分析，以及对采用信号量实现线程的互斥和同步问题进行了详细的论述，最后给出了利用Delphi编写的线程的框架。 相似文献
2.
依据松辽盆地西南部新站地区嫩江组三段孢粉和藻类化石百分含量纵向变化特征,自下而上划分7个能识别水体盐度变化的孢粉和藻类组合：Cyathidites Pinuspollenites Dinogymniopsis组合,指示缩小的微咸水湖相沉积环境;Dinogymniopsis Leiosphaeridia Pinuspollenites组合,代表水域扩大的微咸水湖相沉积环境;Cicatricosisporites Pinuspollenites Botryococcus组合,代表水域缩小的淡水-微咸水湖相沉积环境;Dinogymniopsis Chlamydophorella Taxodiaceaepollenites组合,反映淡水与微咸水频繁交互变化的浅湖相沉积环境;Cicatricosisporites Pinuspollenites Pediastrum组合,代表水域缩小的淡水湖相沉积环境;Nenjiangella Balmula Cyathidites组合,代表水域范围较大的淡水湖相沉积环境;Cyathidites Trilobosporites Botryococcus组合,指示水域缩小的微咸水湖相沉积环境。 相似文献
3.
滇东北地区铅锌矿产资源丰富,就其原因可归于区内具有特征性地质环境:含矿地层是一套局限性滨-浅海环境沉积作用形成的以碳酸盐为主与砂、泥岩层呈不等厚交替出现的沉积建造,区内有较好的含矿层(碳酸盐层)与遮挡层相结合的地层成矿条件;矿区地质构造复杂,因经历了多期的构造运动,形成近于等间距排列的逆冲推覆体构造及与之相伴生的次级断裂和褶皱构造;同时,多期次的构造运动,也引起岩浆多次沿深大断裂发生侵入或喷发作用;在成矿作用上,复杂、多层次的地质构造为成矿作用提供了不同类型的导矿、容矿构造,岩浆作用一方面为成矿提供物源,另一方面为成矿作用提供热动力,为矿液加热,促使成矿热液得以循环运动,从而在有利部位发生交代作用而成矿。 相似文献
4.
Models are presented which illustrate the various methods used for the determination of the thickness and nature of deep seismic boundaries according to the observed amplitude and frequency of subcritical reflected waves. From this study it becomes clear that the model which most nearly satisfies the observational requirements is one in which the boundaries are represented by a zone of thin diverse lamellae which produce localized velocity inversion. 相似文献
5.
A modified version of the economic rent model is applied to the significant urban-waterfront changes which have characterized most European and North American port cities during the twentieth century. The model is at this stage conceptual, although supported by case studies, and employs elements which are characteristic of the majority of waterfront renewal literature. The model addresses four different conditions, three of which trace the evolution which has characterized the traditional inner-city port. The first analyzes the conditions prevailing prior to the late 1950s, when most ocean cargo still used the traditional harbor. The second application of the model relates to the dynamic changes which started in the late 1950s and lasted approximately 20 years, a period in which many piers and warehouses were abandoned and destroyed. The urban-waterfront renewal efforts which have occurred in both Europe and North America are analyzed in the third phase, which emphasizes boundary changes and potential and real economic rent windfalls accruing to landowners in the path of or adjacent to proposed urban-waterfront renewal efforts. The final application of the model reviews the impact on both economic rents and land uses of improvements to the shore and nearshore marine environment. 相似文献
6.
由于地质过程的复杂性及成矿过程的多期次叠加性,原始重磁异常往往是多种地质因素的混合信息,既包含区域背景异常信息,也包含与矿床(体)、矿化蚀变带以及隐伏岩体等与找矿密切相关的地质要素所引起的局部重磁异常.如何从复杂的叠加重磁异常中分离出具有找矿意义的局部异常,是当前矿产勘查和资源潜力评价工作中面临的难题之一.采用经验模态分解(EMD)方法来分解重磁异常,为提高分解的稳健性提出了用双调和样条插值(BSI)进行包罗面插值的新方法,并以云南个旧地区重磁数据为例,对其进行非线性多尺度分解,实现对区域异常与局部重磁异常的分离,揭示了深层次找矿信息并拓宽了经验模态分解方法的应用领域. 相似文献
7.
A method is presented which allows the computation of the displacements and pore pressures which are generated in an elastic soil when excavation is carried out. The formulation is based on Biot's theory and is fully coupled, with consideration also given to the effects of the lowering of the water table which often accompanies the excavation of soil. Example problems are solved to illustrate the theory which has been presented. 相似文献
8.
Current concepts of the important covalent aspects of chemical bonding in silicates are discussed with special reference to the layer structures of the clay minerals.The features which are common to the structures of the kaolinite group of minerals and of the mica-derived group are seen to imply that processes which take place at ordinary temperatures and pressures proceed without disruption of large articulated assemblages; and those features which differentiate between the two types are seen to limit the conditions under which members of the respective groups may develop. 相似文献
9.
W. Siegl 《Mineralium Deposita》1974,9(3):289-295
Epimetamorphic ores which were collected on the dumps of the mining area Arzberg-Haufenreith show relicts and structures which point to a genesis of the type Meggen respectively Rammelsberg. Other arguments for this are mica-layers rich in Ilmenite, which are very probably representing basic metamorphic tuffs. 相似文献
10.
根据越界开采定义,提出矿山越界开采技术方法和技术路线。通过开展2012年度广东省矿山越界开采遥感调查,获取较为真实的矿山越界开采最新状况,且根据近三年广东省矿山越界开采遥感动态监测所获得的数据,得出矿山越界开采,呈日益严重的趋势。通过遥感调查与监测,指出广东省矿山越界开采存在的主要问题,并提出有益的建议和对策,希望遥感能够作为技术支撑更好地为矿政管理服务。 相似文献
11.
《Journal of Structural Geology》1987,9(1):121-126
When photographs of outcrops are required for detailed and/or accurate structural work the photographic image should be parallel to the outerop surface. A method has been developed which allows oblique photographs to be corrected when processed. The method imposes certain restrictions on the combinations of camera and enlarger lenses which will yield a correctly proportioned print, and graphs are presented which predict suitable combinations for a wide range of conditions. The technique has been successfully applied to several problems, one of which is presented as an illustrative example. 相似文献
12.
探地雷达复信号分析的几点讨论 总被引：3，自引：2，他引：3
采用H ilbert变换的复信号分析方法,求取相位时对噪声很敏感,所以分析前的滤波处理是非常重要的,常用的反正切求取相位角方法,不利于求取包含真实反射信息的相位θ(t)。针对以上两个问题,采用了与探地雷达垂向分辨能力相关的尺度,对原始数据进行了滤波操作。滤波后的数据保证了与原始数据相同的分辨能力,有效地压制了干扰信号。同时,具有良好的数学性质,为复信号分析提供了有利的条件。利用反余弦计算相角,方便了程序设计,且求得的相角易于变换为真实相角(ω0t θ(t)),为提取真正与反射信息相关的相位θ(t)提供了便利。应用优化方法求解瞬时相位、瞬时频率等信息,将真正与反射信息相关的θ(t)与ω0t分离,提高了分辨能力,同时还可得到ω0随时间变化的曲线,为分析探地雷达的频散现象提供了依据。 相似文献
13.
Cüneyt Akal Osman Candan O. Ersin Koralay Roland Oberhänsli Fukun Chen Dejan Prelević 《International Journal of Earth Sciences》2012,101(1):177-194
Afyon Zone, which was derived from the Anatolide–Tauride platform during closure of the Neo-Tethys, is made up of pre-Mesozoic
basement and unconformably overlying Triassic–Early Tertiary cover series. The Afyon Zone contains widespread metavolcanic
rocks, which are dominated by rhyolite, dacite, and trachyandesite. They form a distinct volcanic succession, which is separated
from the underlying Silurian–Lower Carboniferous metacarbonates and meta-siliciclastics by a regional unconformity. Trachyandesitic
metavolcanics are made up of massive lava flows, pyroclastics and epiclastics, less frequently, domes and dikes, which were
developed on a deeply eroded subaerial landmass. U/Pb and Pb/Pb zircon geochronology yielded Lower Triassic (~250 Ma) ages,
which are interpreted as extrusion age of trachyandesitic volcanics. Based on the stratigraphic, geochronological, and geochemical
data, we suggest that these Lower Triassic magmatic rocks represent an extensional tectonic setting on the northern active
margin of the Gondwana, which led to the development of the northern branch of the Neo-Tethys. 相似文献
14.
近年来,航空物探项目主要是使用Oasis montaj软件完成数据处理工作,最终提交的成果图件采用MapGIS地理信息系统软件绘制。由于两种软件系统采用的数据格式及兼容性不尽相同,因此采用Visual Basic编程语言编制专用程序,实现两种软件系统数据格式的接口,同时解决MapGIS中剖面平面图的绘制问题。这一问题的解决既发挥了Oasis montaj软件强大的数据处理功能,又充分利用MapGIS软件成熟的绘图功能,同时在项目实施过程中大大提高了数据处理和成果图件绘制的效率,取得了较好的应用效果。 相似文献
15.
刘代志 《大地构造与成矿学》1993,17(1):31-38
本文分析了盆地研究的历史现状、基本内容和特点,提出了盆地,特别是煤盆地深层构造地球物理研究的基本思路和方法步骤,在此基础上,给出了盆地深层构造地球物理信息处理系统的程序结构框架.最后,以鲁西西部煤盆地为例,给出了盆地深层构造的形态特征等有关处理成果图. 相似文献
16.
木孜塔格-鲸鱼湖断裂带特征、演化及其意义 总被引：7，自引：2，他引：5
通过对东昆仑山木孜塔格—鲸鱼湖断裂在青藏高原北部陆内变形过程中形成的构造形迹、沉积建造、新生代火山活动、地球物理场变化综合研究,以野外第一手资料重建该过程的演化历史,认为木孜塔格—鲸鱼湖断裂是青藏高原北部陆内变形过程遗留的重要地质证据,卫星遥感图像上显示极为明显,它具有重要的区域构造意义。首先,发育大规模由北向南的叠瓦式逆冲推覆构造,新近纪由南向北沿构造带分布着东西向平行排列的"堑垒"相间式断陷盆地;其次还见有大量中性火山岩浆沿该断裂及其次级断裂溢出分布,成因分析表明其来源于陆内俯冲作用;第三,该断裂的走向延伸线上现今还发生较大规模的地震活动。综合分析表明,该断裂作为与柴达木地块南部构造边界断裂彼此平行的南东东向大型走滑断裂带,具有左行走滑构造分量,应是青藏高原北缘亚洲大陆向北东逃逸的主要断裂系统。 相似文献
17.
18.
红水河中上游流域岩溶地下水水质影响因素的R型因子分析 总被引：2，自引：0，他引：2
为了了解红水河中上游流域地下水污染情况,并对其进行防治与管理,利用R型因子分析法对红水河中上游流域的130组水化学数据进行分析,识别出影响区内岩溶地下水水质的因子3个。因子1以Ca2+、HCO3-、总硬度和溶解性总固体为主,反映了水-岩作用（碳酸盐溶解）对地下水水化学组分的影响;因子2以K++Na+、Cl-和NO3-为主,揭示了农业污染（农药、化肥、牲畜粪便等）和生活废水对农业区地下水水化学组分的影响;因子3以Mg2+、SO42-和F-为主,反映了工矿业污染对北部矿区地下水水化学组分的影响。结果表明,因子1、因子2和因子3与人类活动密切相关,今后应加强监管和防治。 相似文献
19.
Masanori Miyake 《Chemical Geology》1987,60(1-4):351-359
Based on the analysis of some of the physical and chemical properties of the reddish-colored soils from southeast Brazil four fertility classes of soils were proposed. The soils of class 1 which are characterized by a low inherent fertility are sandy soils which become less fertile after cultivation. The soils of class 2 which are derived from carbonate-cemented sandstone have a high base status under forest vegetation, but become very poor after cultivation and erosion. The soils of class 3 which have a moderate inherent fertility become more fertile after cultivation along with liming and fertilization. Class-4 soils are inherently fertile and their fertility can be maintained and enhanced easily by management practices. The potentially self-improving soils of classes 3 and 4 have a phosphate sorption coefficient above 1000 which corresponds to a definite content in clay, free Fe, total P, and water-soluble silica. 相似文献