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排序方式: 共有865条查询结果,搜索用时 15 毫秒
851.
介绍了新型大容量存储器K9K8G08U0A的基本组织结构,重点讲述了存储器与ATmega128L单片机外部存储器接口的硬件连接方式以及存储器的主要操作流程和部分C语言代码。  相似文献   
852.
延9油层是靖边油田东坑大阳湾地区的主力产层.将沉积体系、低幅构造、古地貌等作为一个有机的整体,对靖边油田东坑大阳湾地区的油藏控制因素进行重点分析.结果表明,古地貌控制着东坑大阳湾地区延9沉积相的展布及低幅构造的形成,并通过与低幅构造、沉积砂体的良好配置,控制着油藏的分布.  相似文献   
853.
在考虑选择射线源能量、计算射线源的穿透能力或研究材料屏蔽性能时,被检测材料的线衰减系数是一个重要参数。本文基于9 MeV工业CT系统,提出一种简单的线衰减系数测定方法,对CT检测工作中常见的铝(Al)、钨(W)和钢(Fe)材料进行线衰减系数的测定。首先,选取不同厚度的金属材料,分别放置于探测器与射线源之间,使中心射束垂直透过金属材料;然后分别读取不同厚度金属材料下探测器通道的示数,通过线性拟合计算出被检测材料的线衰减系数;最后将测定结果与文献和NIST数据库中的结果进行比较。结果表明,通过实验测定的三种材料的线衰减系数比较准确,实验结果可用于相同材料的CT检测中,也可采用本文方法计算其他材料的线衰减系数。  相似文献   
854.
基于小波分析的精细地层划分对比在庄9井区的应用   总被引:2,自引:0,他引:2  
为了满足庄9井区低渗透油藏描述中建立精细地层对比格架的要求,从研究区多种资料和小波系数模极值点、过零点与信号突变点数学模型出发,选用小波分析技术开展精细地层划分对比。通过对常规典型测井曲线小波变换,选用第3层细节信号重构测井曲线,将小波重构曲线与常规曲线结合起来,对比分析建立研究区精准地层对比剖面,并将此技术引入到储层隔夹层分析。研究表明,基于小波分析的地层划分对比与隔夹层分析结果可靠,满足高分辨率层序地层划分要求,效果好于传统的测井曲线分层对比方法。  相似文献   
855.
The Jiangshan-Shaoxing-Pingxiang Fault(JSP Fault) is traditionally considered as the boundary between the Yangtze and Cathaysia blocks in South China. Whether the previously defined Shenshan and Kuli formations located along the JSP fault and near the Xinyu City, Jiangxi Province, are continuous strata or parts of a tectonic mélange is important for understanding the geological history of South China. A carbonaceous phyllite from the area, previously considered as part of the Neoproterozoic Shen...  相似文献   
856.
PL19-9油田是典型的疏松砂岩稠油油藏,其正式投入开发不久后,与PL19-3设计注水量相比,暴露出注入压力高、油井欠注等一系列问题,原油产量明显下降。本文在深化研究该油田储层地质特征的基础上,利用储层敏感性矿物分析、配伍性实验、电镜能谱、X射线衍射、红外光谱分析、室内岩芯驱替、平台水质调研等手段,明确了注水过程中储层损害机理。研究结果表明:PL19-9油田岩石胶结疏松、黏土矿物含量高、层间非均质性强是注水困难的客观因素;储层具有强速敏,注入强度过大是影响注水效果的重要原因;注入水与地层水存在轻度不配伍,不配伍比例在3∶1—1∶3之间;注入40PV时损害程度为中等偏弱;水质不达标是注水困难的关键外因,注入水中对储层造成伤害的物质主要为油污、腐蚀产物,其次为少量垢和地层颗粒。针对上述损害机理采取相应的措施,提高注水井的吸水能力,保证注采平衡,促进高效稳产。  相似文献   
857.
Over the last decade, hundreds of climate change adaptation projects have been funded and implemented. Despite the importance of these first-generation adaptation projects for establishing funders and implementors’ “best practices,” very little is known about how early adaptation projects have endured, to what ends, and for whom. In this article, I propose a community-based methodology for ex-post assessment of climate change adaptation projects. This methodology contributes to recognitional justice by asking the individuals and collectives tasked with sustaining adaptation initiatives to define adaptation success and what criteria for success should be assessed. I apply this subjective assessment approach in 10 communities across Ecuador that participated in an internationally funded adaptation project that concluded in 2015. My analysis draws together participatory mapping, walking interviews with local leaders, participant observation, and surveys with former project participants. The results highlight that even adaptation projects that were deemed highly successful at their closure have uncertain futures. I find that the sustainability mechanisms that were envisioned by project implementors have not functioned, and communities are shouldering the burden of reviving failing adaptation interventions. These findings highlight that the current model of episodic funding for climate change adaptation projects and evaluation processes needs to be revisited to acknowledge the long-term challenges faced by communities. This analysis also calls attention to the importance of ex-post assessment for adaptation projects and the potential of subjective assessment approaches for building more ontological and epistemological pluralism in understandings of successful climate change adaptation.  相似文献   
858.
As part of a long‐term project to determine abundances and astrophysical properties of evolved red stars in open clusters, we present high‐precision DDO photoelectric observations for a sample of 33 red giant candidates projected in the fields of nine Galactic open clusters. These data are supplemented with UBV photoelectric photometry of 24 of these stars as well as with CORAVEL radial‐velocity observations for 13 red giant candidates in four of the clusters. We also present Washington photoelectric photometry of a small sample of red giant candidates of the open cluster Ruprecht 97. The likelihood of cluster membership for each star photometrically observed and for 23 additional red giant candidates with UBV and DDO data available in the literature, is evaluated by using two independent photometric criteria. Nearly 82% of the analysed stars are found to have a high probability of being cluster giants. Photometric membership probabilities show very good agreement with those obtained from CORAVEL radial velocities. While E (BV) colour excesses were determined from combined BV and DDO colours, calibrations of the DDO system were used to derive MK spectral types, effective temperatures and metallicities. The derived DDO metallicities range between values typical of moderately metal‐poor clusters ([Fe/H] = –0.19) to moderately metal‐rich ([Fe/H] = 0.25) ones. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
859.
Energy and mobility poverty limits people’s choices and opportunities and negatively impinges upon structural economic and social welfare patterns. It also hampers the ability of planners to implement more equitable and just decarbonization pathways. Research has revealed that climate policies have imposed a financial burden on low-income and other vulnerable groups by increasing food and energy prices, leading as well to global inequality. Similarly, researchers have warned that in developing countries, emission mitigation policies could increase poverty rates and even frustrate progress towards universal access to clean energy. This research explores whether low-income social groups experience a 'double energy vulnerability', a situation that simultaneously positions people at heightened risk of transport and energy poverty. We investigate this 'double vulnerability' through original data collection via three nationally representative surveys of Mexico (N = 1,205), the United Arab Emirates (N = 1,141), Ireland and Northern Ireland (N = 1,860). We draw from this original data to elaborate on the sociodemographic attributes, expenditure and behaviour emerging from energy and transport use, focusing on themes such as equity, behaviour and vulnerability. We propose energy and transport poverty indexes that allow us to summarize the key contributing factors to energy and transport poverty in the countries studied and uncover a strong correlation between these two salient forms of poverty. Our results suggest that energy and transport poverty are common issues regardless of the very different national, and even sub-national, contexts. We conclude that energy and transport poverty requires target policy interventions suitable for all segments of society, thus enabling contextually-tailored, just energy transitions.  相似文献   
860.
Long-term global emission scenarios enable the analysis of future climate change, impacts, and response strategies by providing insight into possible future developments and linking these different climate research elements. Such scenarios play a crucial role in the climate change literature informing the Intergovernmental Panel on Climate Change’s (IPCC) Assessment Reports (ARs) and support policymakers. This article reviews the evolution of emission scenarios, since 1990, by focusing on scenario critiques and responses as published in the literature. We focus on the issues raised in the critiques and the possible impact on scenario development. The critique (280) focuses on four areas: 1) key scenario assumptions (40%), 2) the emissions range covered by the scenarios and missing scenarios (25%), 3) methodological issues (24%), and 4) the policy relevance and handling of uncertainty (11%). Scenario critiques have become increasingly influential since 2000. Some areas of critique have decreased or become less prominent (probability, development process, convergence assumptions, and economic metrics). Other areas have become more dominant over time (e.g., policy relevance & implications of scenarios, transparency, Negative Emissions Technologies (NETs) assumptions, missing scenarios). Several changes have been made in developing scenarios and their content that respond to the critique.  相似文献   
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