虚拟化在气象局数据中心的应用

通过对虚拟化技术的研究,结合泰州气象局机房布局、数据中心服务器、存储的应用情况以及新业务的增长需求,提出了有针对性的气象业务虚拟化的解决方案。通过新购刀片服务器、FC SAN存储、VMware软件以及对原有的服务器、存储、网络进行整合改造,搭建了气象业务的虚拟化运行模式,最终实现资源的统一调度管理,建成了一个通用性强、扩展性好、可用性高的数据中心。文章同时简述了虚拟化在数据中心的实施过程、应用注意事项、业务迁移适应性分析以及最终的效益。     

M-Quadtree索引:一种基于改进四叉树编码方法的云存储环境下空间索引方法

为了解决基于"键-值"模型的云存储环境仅支持简单的关键字查询,不支持多维空间查询的问题,提出了一种新的分布式空间索引方法——M-Quadtree索引。在索引构建过程中,设计了一种基于改进四叉树的空间数据划分方法,该方法规定了叶节点区域的最小数据量,通过四叉树叶节点的再合并,解决了划分后各子区域间存储量不平衡的问题,并且满足了MapReduce并行化要求。给出了MapReduce框架下M-Quadtree索引的快速构建、查询与更新算法,并在搭建的Hadoop平台进行了关键参数对索引效率的影响以及不同规模数据下索引的创建、查询和更新试验。与现有分布式空间索引的对比试验及分析结果表明,M-Quadtree索引在数据存储量负载均衡、算法并行化和空间查询效率等方面表现得更好。     

Reactive transport impacts on recovered freshwater quality during multiple partially penetrating wells (MPPW-)ASR in a brackish heterogeneous aquifer

The use of multiple partially penetrating wells (MPPW) during aquifer storage and recovery (ASR) in brackish aquifers can significantly improve the recovery efficiency (RE) of unmixed injected water. The water quality changes by reactive transport processes in a field MPPW-ASR system and their impact on RE were analyzed. The oxic freshwater injected in the deepest of four wells was continuously enriched with sodium (Na⁺) and other dominant cations from the brackish groundwater due to cation exchange by repeating cycles of ‘freshening’. During recovery periods, the breakthrough of Na⁺ was retarded in the deeper and central parts of the aquifer by ‘salinization’. Cation exchange can therefore either increase or decrease the RE of MPPW-ASR compared to the RE based on conservative Cl⁻, depending on the maximum limits set for Na⁺, the aquifer’s cation exchange capacity, and the native groundwater and injected water composition. Dissolution of Fe and Mn-containing carbonates was stimulated by acidifying oxidation reactions, involving adsorbed Fe²⁺ and Mn²⁺ and pyrite in the pyrite-rich deeper aquifer sections. Fe²⁺ and Mn²⁺ remained mobile in anoxic water upon approaching the recovery proximal zone, where Fe²⁺ precipitated via MnO₂ reduction, resulting in a dominating Mn²⁺ contamination. Recovery of Mn²⁺ and Fe²⁺ was counteracted by frequent injections of oxygen-rich water via the recovering well to form Fe and Mn-precipitates and increase sorption. The MPPW-ASR strategy exposes a much larger part of the injected water to the deeper geochemical units first, which may therefore control the mobilization of undesired elements during MPPW-ASR, rather than the average geochemical composition of the target aquifer.     

A new assessment model for evacuation vulnerability in urban areas

In the high-speed urbanization process of China, the urban population has been increasing significantly, leading to a high-density aggregation of population. However, the sharp increase in population density has not produced commensurate improvements in the road networks. On the contrary, the population increase induced a serious evacuation vulnerability, which cities experience during various hazards and catastrophic events. Therefore, research on evacuation vulnerability is important to urban planning. To assess the evacuation vulnerability, the optimal and worst scenarios should be considered because all possible evacuation plans occur between these extremes. However, most previous evacuation vulnerability studies are based on the worst-case scenario, only providing an upper bound of a potential evacuation assessment. To provide a more comprehensive theoretical basis for decision-makers to understand the consequences caused by all possible evacuations, this paper proposes an optimal evacuation vulnerability assessment model that provides the lower bound on potential evacuation difficulties. The model is solved by a stepwise spreading algorithm based on Graph Theory. Subsequently, to evaluate the effectiveness of the model, the study adopts the model to assess the evacuation capability of different road network topologies. A comparison with previous research was performed. The model was demonstrated in an application to the South Luogu Alley of Beijing, China. The significance of this paper is that the combination of our model with previous research may provide a more complete theoretical basis for an evacuation vulnerability assessment.     

A New Reference Material for Tritium Organic Molecules in Sediment: Results of an International Intercomparison Exercise

Solid matrix ³H reference materials are challenging to prepare given the volatile nature of ³H and are often unrepresentative of the range of ³H forms that may be encountered during routine analysis. As a result, few ³H reference materials are currently available, undermining verification of analytical techniques for environmental ³H measurement. To address this, an International Working Group on Organically‐Bound Tritium Analysis determined to produce a tritium natural matrix reference material (NMRM). The reference material comprises marine sediment blended with sewage sludge contaminated with ³H‐organic species arising from authorised discharges from a radiopharmaceutical manufacturing site. Previous studies have demonstrated that the ³H species have persisted in the environment over three decades providing valuable supporting data to underpin the characterisation of the NMRM. The preparation and characterisation of the NMRM are described along with the subsequent application of the reference material in an international intercomparison exercise involving nineteen laboratories from nine countries. A reference value of 168 ± 22 Bq kg^?1 was derived from the data arising from the proficiency test.     

基于改进K-SVD字典学习方法的地震数据去噪

为实现更好的地震数据去噪技术,笔者引入一种新的算法:快速迭代收缩阀值法(FISTA),通过FISTA和K-奇异值分解(K-SVD)不断迭代更新K-SVD字典,利用更新得到的K-SVD字典对地震数据进行稀疏表示,去除稀疏系数中较小的数值,使数据中的随机噪声得到压制。对层状模型合成地震记录,Marmousi模型合成地震记录以及实际地震数据进行对比实验,得出FISTA算法较OMP算法能更好地提高地震数据的信噪比,同时有效地保护了反射信号。     

微波等离子体原子发射光谱法测定偏远矿区海泡石中的主微量元素

海泡石是具有层状结构的含水富镁硅酸盐黏土矿物,其中无机元素含量是揭示其成矿物质来源、成矿流体性质和矿床成因的重要依据,通常采用电感耦合等离子体发射光谱/质谱法(ICP-OES/MS)进行测定,等离子体(ICP)的高温激发会产生成大量谱线干扰,维持ICP稳定工作需使用高纯氩气,持续供气对于偏远矿区海泡石的检测还将面对气体采购和运输不便的问题。本文基于微波等离子体原子发射光谱(MP-AES)的低温激发技术减少光谱干扰,建立了准确测定偏远矿区海泡石中主量元素Mg、Al、Ca、Fe、K、Na和微量元素Cu、Zn、Mn、Pb含量的分析方法。利用硝酸-盐酸-氢氟酸混合酸对海泡石进行微波消解,避免了样品处理过程中分析元素的损失,加快了样品处理速度,同时提高了样品溶液的稳定性。通过选择各元素光谱线的分析波长,并利用快速线性干扰校正(FLIC)技术校正光谱干扰,以Lu为内标元素校正基体效应,提高了灵敏度和准确度。各元素的检出限为0.19～14.6μg/L。海泡石国家标准物质(GBW07138)各元素测定值与认定值的相对误差在-5.0%～6.7%之间。本方法具有检出限低、线性范围宽、结果准确等优点;MP-AES采用自带的氮气发生器为等离子体提供氮气作为工作气,无需引入复杂气体,提高了分析效率,尤其适用于气体采购和运输不便的偏远矿区。     

高山区雪堆储雪的实验和模拟计算

随着全球气候变暖,滑雪运动呈现出对气候变化高度的敏感性和依赖性,各地滑雪季将不同程度地缩短。储雪作为一种应对气候变化的方法在雪务保障中逐渐得到研究和应用。在新疆阿勒泰地区吉木乃县开展储雪实验,应用谐波反应法研究了雪堆融化量与外界空气温度、太阳辐射和绝热保温结构热学性能之间的定量关系。实验中,覆盖两层绝热保温材料雪堆1的平均融化量为18.0 kg·d^-1（相当于初始质量的0.85%）,未覆盖绝热保温材料雪堆2的平均融化量为120.8 kg·d^-1（相当于初始质量的6.67%）。模拟期间观测到的雪堆1质量减少了1 438.0 kg,对应的模拟值为1 520.8 kg。谐波反应法可以为评价绝热保温结构的热学性能和提前确定储雪量提供重要的参考依据。由于许多物理过程都未考虑,导致模拟的雪堆融化量与实际融化量之间存在不确定性。雪堆所用绝热保温结构的性能可以用反射率、总传热系数、衰减度和延迟时间来衡量。     

白涧铁矿南区复杂地层钻探施工技术

邢台白涧铁矿南区地层岩石破碎、部分地层含角砾、胶结性差、漏失严重,钻探施工中存在掉块卡钻、缩径、坍塌、埋钻及孔内泥浆全部漏失等难题。通过优化钻孔结构、使用新工艺、新方法,合理选择钻进参数,采用绳索取心钻进配合预留技术套管,有效解决了上部煤系地层的坍塌问题;采用反丝套管的方法,极大地减轻了由于地层缩径、掉块引起的套管下不到位、起拔困难等风险;常规型绳索取心钻杆替代套管方法的采用,提高了含角砾、松散地层的穿过速度,减少了钻探工作量的报废,加快了施工进度;特别是高胎体双水口钻头的使用,提高了钻进效率,节约了钻探施工成本,项目得以如期完成。     

Inter‐laboratory Characterisation of Apatite Reference Materials for Chlorine Isotope Analysis

Here we report on a set of six apatite reference materials (chlorapatites MGMH#133648, TUBAF#38 and fluorapatites MGMH#128441A, TUBAF#37, 40, 50) which we have characterised for their chlorine isotope ratios; these RMs span a range of Cl mass fractions within the apatite Ca₁₀(PO₄)₆(F,Cl,OH)₂ solid solution series. Numerous apatite specimens, obtained from mineralogical collections, were initially screened for ³⁷Cl/³⁵Cl homogeneity using SIMS followed by δ³⁷Cl characterisation by gas source mass spectrometry using both dual‐inlet and continuous‐flow modes. We also report major and key trace element compositions as determined by EPMA. The repeatability of our SIMS results was better than ± 0.10‰ (1s) for the five samples with > 0.5 % m/m Cl and ± 0.19‰ (1s) for the low Cl abundance material (0.27% m/m). We also observed a small, but significant crystal orientation effect of 0.38‰ between the mean ³⁷Cl/³⁵Cl ratios measured on three oriented apatite fragments. Furthermore, the results of GS‐IRMS analyses show small but systematic offset of δ³⁷Cl_SMOC values between the three laboratories. Nonetheless, all studied samples have comparable chlorine isotope compositions, with mean 10³δ³⁷Cl_SMOC values between +0.09 and +0.42 and in all cases with 1s ≤ ± 0.25.