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111.
2009年利用大功率人工源极低频电磁技术(CSELF)在位于华北、华南、东北、西北和西南的12个地震台站和几个流动观测点进行了连续30天新的观测试验.结果表明,利用CSELF技术可以在1700 km之外测量到人工源电磁场信号,计算得到的电、磁场功率谱密度和视电阻率与天然源信号相比,抗干扰能力更强,观测信号更稳定,特别有利于识别和捕捉地震等诱发的电磁异常现象,在地震预测监测中具有很大的研究应用潜力.试验还发现,各地震台站和流动测点观测的CSELF信号的强度,与台站或者测量的电、磁场分量相对于发射源的距离、方位有明显的关系;发现在离开发射源的相对近区,场强随距离的衰减,比在相对远区更快;发现接收磁场信号比电场信号较易获得更高信噪比的数据. 相似文献
112.
The sequencing batch reactor (SBR) process has shown great success in the treatment of industrial wastewater from intermittent discharge factories and for the treatment of domestic wastewater from medium or small towns. As automation technology has developed, many studies have been conducted to determine the optimal conditions for the SBR process. This review outlines the progress and application of control strategies that have been developed for the SBR process and provides a summary and comparison of the advantages and disadvantages of various control strategies, especially fixed‐time control strategies and various real‐time control strategies. Moreover, an analysis and discussion of novel optimal control methods for biologic nutrient removal are provided. Although previous studies in this field have greatly enriched our understanding of SBR systems, it is clear that many unsolved problems remain. Therefore, a summary of unanswered questions regarding control strategies for the SBR process is provided and future research directions are suggested. 相似文献
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云南宣威羊场煤矿资源潜力评价 总被引:1,自引:0,他引:1
羊场煤矿经50年开采,资源近于枯竭。通过地质调查和预测,提供可靠依据,为危机矿山新增储量,延长矿山服务年限。 相似文献
115.
《The Cartographic journal》2013,50(4):324-331
AbstractConsiderable attention has been paid in the literature to the changing style of Ordnance Survey mapping in the twentieth century. However, little has been written about the origins of the characteristic appearance of the first multi-colour editions, other that the Ordnance Survey used a military edition that was already in production. The distinctive style grew out of the work of a committee established in 1892 by the War Office to consider future army requirements for a map of the UK. This paper explores the work of the committee and its long-term implications for the look of mapping in the twentieth century. 相似文献
116.
A key challenge for effective, ongoing urban climate adaptation is to adapt institutions within urban governance. While an extensive foundation of empirical knowledge on urban climate adaptation has accumulated over the last decade, our image of institutional adaptation continues to be dominated by a focus on planning. Whilst understandable, this can obscure a fuller range of areas in which institutional adaptation to climate change is being pursued. Furthermore, methodological path dependency in large-N analysis via a common focus on analyzing formal planning documents risks a skewed perspective as such documents may only offer a partial view. Building on the rich range of work to date assessing climate adaptation in cities, and notwithstanding continued major gaps such as in small-medium cities, we now need to find ways to examine the diversity of institutional adaptation occurring in practice, and to comparatively draw on the situated interpretive knowledge of case experts within individual cities to do so. With this aim in mind, this paper explores institutional adaptation in a specific domain (urban water) in a sample of 96 major cities across six continents through a survey of 319 case experts, examining the diversity of institutional adaptation across contexts and exploratively probing its drivers. Findings show that multiple forms of institutional adaptation are being jointly pursued in cities across all continents, leaning towards ‘softer’ rather than ‘harder’ forms, but nonetheless revealing a wide range of activity. Patterns in drivers suggest a political explanation for institutional adaptation (e.g. involving change agents and political pressure) rather than a rational one (e.g. involving response to climate-related risks and/or extreme events). Overall, there is a need to combine parsimony with expanded interpretive sensibility in advancing large-N research on institutional adaptation diversity in comparative perspective. 相似文献
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财务内部控制是为了保证单位财务目标的实现,是单位内部控制的核心。我国施工单位以项目管理为核心的经营管理体制已基本形成。受投资规模大、生产周期长、影响因素多、竞争异常激烈等行业特点所限,财务风险贯穿于施工单位工程项目施工全过程。因此,施工单位财务风险管理更为复杂。本文以内部控制、COSO基本框架、系统工程等作为理论基础,系统地分析了施工单位的财务风险点,提出了"以项目成本控制为核心,以项目全过程管控为主线,以全面预算控制为抓手"的施工单位财务内部控制基本框架结构。 相似文献
119.
大口径管井降水方法是应用较为广泛的、成熟的地下水控制措施。但因施工准入门槛低,在土建施工造价中所占比重较小,往往得不到重视,常出现边坡失稳、底板隆起等重大损失。基于抽水试验成果完成方案设计,抓准施工质量关键点是实现良好降水效果的必要条件。 相似文献
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