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51.
讨论了使用可执行对象模型开发通信系统的相关概念、方法和技术,提出了一个利用可执行对象模型进行通信系统开发的过程,以提高通信软件质量,缩短开发周期,减少软件维护费用。  相似文献   
52.
面向数字孪生城市的智能化全息测绘   总被引:2,自引:0,他引:2  
以大数据、物联网、人工智能、虚拟现实、云计算、智能驾驶等新技术为代表的信息化浪潮席卷全球,数字世界与物理世界正形成两大平行发展、相互作用的体系,数字孪生技术应运而生。随着物联网技术(IOT)的发展,数字孪生的理念被引入到智慧城市建设中来,深刻影响着城市规划、建设与治理。笔者所在单位面向数字孪生城市和自然资源统一监管对测绘地理信息的新需求,在全国开创性地开展了面向数字孪生城市的智能化全息测绘试点工作。本文结合上海市智能化全息测绘试点工作,从数字孪生城市、数字孪生城市对地理信息的新需求、智能化全息测绘关键技术及测绘成果等方面展开了论述,重点介绍了智能化全息测绘的技术体系和产品体系,以及在社会各领域的应用成果。  相似文献   
53.
In this study, attempts are made to investigate the effects of inertial soil–structure interaction (SSI) on damping coefficients subjected to pulse-like near-fault ground motions. To this end, a suit of 91 pulse-like near-fault ground motions is adopted. The soil and superstructure are idealized employing cone model and single-degree-of-freedom (SDOF) oscillator, respectively. The results demonstrate that soil flexibility reduces and amplifies the damping coefficients for structural viscous damping levels higher and lower than 5%, respectively. The coefficients reach one for both acceleration and displacement responses in cases of dominant SSI effects. The effect of structure dimensions on damping confidents are found insignificant. Moreover, damping coefficients of displacement responses are higher than those of acceleration responses for both fixed-base and flexible-base systems. Evaluation of damping correction factor introduced by FEMA 440 shows its inefficiency to predict acceleration response of soil–structure systems under pulse-like near-fault ground motions. Soil flexibility makes the damping correction factor of moderate earthquakes more pronounced and a distinctive peak value is reported for cases with dominant SSI effects.  相似文献   
54.
The Sangdong scheelite–molybdenite deposit in northeast South Korea consists of strata-bound orebodies in intercalated carbonate-rich layers in the Cambrian Myobong slate formation. Among them, the M1 layer hosts the main orebody below which lie layers of F1–F4 host footwall orebodies. Each layer was first skarnized with the formation of a wollastonite + garnet + pyroxene assemblage hosting minor disseminated scheelite. The central parts of the layers were subsequently crosscut by two series of quartz veining events hosting minor scheelite and major scheelite–molybdenite ores, respectively. The former veins associate amphibole–magnetite (amphibole) alteration, whereas the latter veins host quartz–biotite–muscovite (mica) alteration. Deep quartz veins with molybdenite mineralization are hosted in the Cambrian Jangsan quartzite formation beneath the Myobong formation. In the Sunbawi area, which is in close proximity to the Sangdong deposit, quartz veins with scheelite mineralization are hosted in Precambrian metamorphic basement. Three muscovite 39Ar–40Ar ages between 86.6 ± 0.2 and 87.2 ± 0.3 Ma were obtained from M1 and F2 orebodies from the Sangdong deposit and Sunbawi quartz veins. The Upper Cretaceous age of the orebodies is concordant with the published ages of the hidden Sangdong granite, 87.5 ± 4.5 Ma. This strongly suggests that the intrusion is causative for the Sangdong W–Mo ores and Sunbawi veins.Fluid inclusions in the quartz veins from the M1 and F2 orebodies, the deep quartz-molybdenite veins, and the Sunbawi veins are commonly liquid-rich aqueous inclusions having bubble sizes of 10–30 vol%, apparent salinities of 2–8 wt% NaCl eqv., and homogenization temperatures of 180–350 °C. The densities of the aqueous inclusions are 0.70–0.94 g/cm3. No indication of fluid phase separation was observed in the vein. To constrain the formation depth in the Sangdong deposit, fluid isochores are combined with Ti–in–quartz geothermometry, which suggests that the M1 and F2 orebodies were formed at depths of 1–3 km and 5–6 km below the paleosurface, respectively. The similarity of the Cs (cesium) concentrations and Rb/Sr ratios in the fluid inclusions of the respective orebodies indicate an origin from source magmas having similar degrees of fractionation and enrichment of incompatible elements such as W and Mo. High S concentrations in the fluids and possibly organic C in the sedimentary source likely promoted molybdenite precipitation in the Sangdong orebodies, whereas the scheelite deposition in the deep quartz–molybdenite veins hosted in the quartzite is limited by a lack of Ca and Fe in the hydrothermal fluids. The molybdenite deposition in the Sunbawi quartz–molybdenite veins hosted in the Precambrian metamorphic basement rocks was possibly limited by a lack of reducing agents such as organic C.  相似文献   
55.
川西新场气田蓬莱镇组陆相地层高分辨率层序地层学研究   总被引:20,自引:4,他引:20  
利用钻井岩芯、测井和地震资料 ,运用高分辨率层序地层学理论及方法 ,对新场地区蓬莱镇组进行不同级次的基准面旋回层序划分 ,识别出 45~ 47个短期、5个中期、2个长期基准面旋回层序 ,并对不同级次的基准面旋回层序的结构类型、叠加样式和平面分布模式进行了较为深入的讨论。在单井分析的基础上 ,以二分时间单元分界线为优选等时对比标志对不同级次的基准面旋回进行了较高精度的等时对比 ,所对比的等时成因地层单元的最高精度可达到相当准层序组 (十万年级 )的短期基准面旋回。建立了新场地区蓬莱镇组高分辨率层序地层格架 ,成功地将单井一维信息转化为气田范围内的三维地层关系信息。并分析了短期基准面旋回过程中可容纳空间 (A)与沉积物补给通量 (S)的比值 (A/S)变化对储集砂体的作用 .文中还利用沉积动力学的地层响应过程特征分析 ,重点讨论了中、短期基准面旋回过程中有利储集砂体的沉积相序列、组合特征、产状类型、控制因素及其与物性的关系。指出发育于长期基准面缓慢上升或下降过程中的三角洲沉积体系 ,为形成储集砂体的必备背景条件 ,而控制沉积体系中储层时空展布和演化规律的因素则主要为中期基准面旋回。在层序地层格架中 ,中期基准面旋回层序界面两侧的储层其储集性最好。以此为依据 ,提  相似文献   
56.
The integration of core sedimentology, seismic stratigraphy and seismic geomorphology has enabled interpretation of delta‐scale (i.e. tens of metres high) subaqueous clinoforms in the upper Jurassic Sognefjord Formation of the Troll Field. Mud‐prone subaqueous deltas characterized by a compound clinoform morphology and sandy delta‐scale subaqueous clinoforms are common in recent tide‐influenced, wave‐influenced and current‐influenced settings, but ancient examples are virtually unknown. The data presented help to fully comprehend the criteria for the recognition of other ancient delta‐scale subaqueous clinoforms, as well as refining the depositional model of the reservoir in the super‐giant Troll hydrocarbon field. Two 10 to 60 m thick, overall coarsening‐upward packages are distinguished in the lower Sognefjord Formation. Progressively higher energy, wave‐dominated or current‐dominated facies occur from the base to the top of each package. Each package corresponds to a set of seismically resolved, westerly dipping clinoforms, the bounding surfaces of which form the seismic ‘envelope’ of a clinoform set and the major marine flooding surfaces recognized in cores. The packages thicken westwards, until they reach a maximum where the clinoform ‘envelope’ rolls over to define a topset–foreset–toeset geometry. All clinoforms are consistently oriented sub‐parallel to the edge of the Horda Platform (N005–N030). In the eastern half of the field, individual foresets are relatively gently dipping (1° to 6°) and bound thin (10 to 30 m) clinothems. Core data indicate that these proximal clinothems are dominated by fine‐grained, hummocky cross‐stratified sandstones. Towards the west, clinoforms gradually become steeper (5° to 14°) and bound thicker (15 to 60 m) clinothems that comprise medium‐grained, cross‐bedded sandstones. Topsets are consistently well‐developed, except in the westernmost area. No seismic or sedimentological evidence of subaerial exposure is observed. Deposition created fully subaqueous, near‐linear clinoforms that prograded westwards across the Horda Platform. Subaqueous clinoforms were probably fed by a river outlet in the north‐east and sculpted by the action of currents sub‐parallel to the clinoform strike.  相似文献   
57.
A distance cartogram is a diagram that visualizes the proximity indices between points in a network, such as time–distances between cities. The Euclidean distances between the points on the distance cartogram represent the given proximity indices. This is a useful visualization tool for the level of service of transport, e.g. difference in the level of service between regions or points in a network and its improvement in the course of time. The two previously proposed methods—multidimensional scaling (MDS) and network time–space mapping—have certain advantages and disadvantages. However, we observe that these methods are essentially the same, and the merits of both these methods can be combined to formulate a generalized solution. In this study, we first formulate the time–space mapping problem, which includes the key features of both of the above stated methods, and propose a generalized solution. We then apply this solution to the time–distances of Japan's railway networks to confirm its applicability.  相似文献   
58.
This paper discusses the analysis and modelling of the hydrological system of the basin of the Kara River, a transboundary river in Togo and Benin, as a necessary step towards sustainable water resources management. The methodological approach integrates the use of discharge parameters, flow duration curves and the lumped conceptual model IHACRES. A Sobol sensitivity analysis is performed and the model is calibrated by applying the shuffled complex evolution algorithm. Results show that discharge generation in three nested catchments of the basin is affected by landscape physical characteristics. The IHACRES model adequately simulates the rainfall–runoff dynamics in the basin with a mean modified Nash-Sutcliffe efficiency measure of 0.6. Modelling results indicate that parameters controlling rainfall transformation to effective rainfall are more sensitive than those routing the streamflow. This study provides insights into understanding the catchment’s hydrological system. Nevertheless, further investigations are required to better understand detailed runoff generation processes.
EDITOR M.C. Acreman; ASSOCIATE EDITOR N Verhoest  相似文献   
59.
通过在实验区内设置不同类型的采样线,对GVG采样线的代表性进行检验.结果表明,高速公路和乡村道路类型的采样线对区域代表性的精度在95%以上;国道为86.726%;省道为65.447%.对于不同的缓冲区,高速公路、省道和乡村道路类型采样线,以200m缓冲区的代表性最好.而国道则以800m缓冲区的代表性最好.对于不同的作物而言,无论何种类型的采样线或者缓冲区,种植面积最大的棉花的精度是最好的.最低的是省道采样线1000m缓冲区,精度是78.146%,最好的是国道采样线800m缓冲区,精度是99.974%.除省道外,其他精度都在94.8%以上.这说明GVG采样线所获得的成数对于区域主要作物的代表性是很好的.  相似文献   
60.
对于已进入开发中后期的碳酸盐岩缝洞型油气藏,进行缝洞单元精细研究非常重要。盲目部署加密井,很容易导致因为所在单元的储量已被动用而失利。本文采用的碳酸盐岩缝洞单元多学科综合划分方法是:在有井控制的地区,首先分析井间连通性,然后结合生产动态、常规解析试井、流体性质、数值试井等多学科资料确定缝洞单元边界;在无井控制的地区,影响连通性最重要的主控因素是储层本身的相互连通性,其次才是断裂和裂缝,这时可在连通性约束下进行储层和裂缝预测,并以此为主要依据确定缝洞单元边界。对塔里木盆地轮古油气田轮古11井区划分出80个缝洞单元,其中有55个为储量未动用单元(潜力单元),并部署了一些加密井,已钻的XW1井获得了成功,投产初期日产油95t,不含水。  相似文献   
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