Quantitative assessment of vegetation cover and soil degradation factors within terrain units for planning,monitoring and assessment of renaturation along oil and gas pipelines

This paper evaluates the renaturation activities applying the quantification of vegetation cover (VC), the site suitability analysis (SSA) based on the predefined criteria (slope steepness category (SSC), soil erodibility factor (K) and VC) and soil erosion model (SEM) results within the terrain units (TUs) along pipeline rights-of-way (RoW). Quantification of VC percentage is performed to assess the overall restored VC from 2005 to 2007. The results of the quantitative analysis in 2007 show that the total area of restored VC is 10.7 km², and 8.9 km² still needs to be restored to comply with the environmental acceptance criteria. As a result of SSA, TUs were prioritized by erosion vulnerability and this allowed to better understand the landscape behaviour in regards to erosion processes. SEM provided more detailed predictions of erosion classes falling into TUs. SEM identified 40% of erosion sites occurred from 2005 to 2010.     

Digital Terrain Modeling and Industrial Surface Metrology: Converging Realms

Digital terrain modeling has a micro- and nanoscale counterpart in surface metrology, the numerical characterization of industrial surfaces. Instrumentation in semiconductor manufacturing and other high-technology fields can now contour surface irregularities down to the atomic scale. Surface metrology has been revolutionized by its ability to manipulate square-grid height matrices that are analogous to the digital elevation models (DEMs) used in physical geography. Because the shaping of industrial surfaces is a spatial process, the same concepts of analytical cartography that represent ground-surface form in geography evolved independently in metrology. The surface topography of manufactured components, exemplified here by automobile-engine cylinders, is routinely modeled by variogram analysis, relief shading, and most other techniques of parameterization and visualization familiar to geography. This article introduces industrial surface-metrology, examines the field in the context of terrain modeling and geomorphology and notes their similarities and differences, and raises theoretical issues to be addressed in progressing toward a unified practice of surface morphometry.     

Nonlinear dynamics and recurrence analysis of extreme precipitation for observed and general circulation model generated climates

A statistical framework based on nonlinear dynamics theory and recurrence quantification analysis of dynamical systems is proposed to quantitatively identify the temporal characteristics of extreme (maximum) daily precipitation series. The methodology focuses on both observed and general circulation model (GCM) generated climates for present (1961–2000) and future (2061–2100) periods which correspond to 1xCO₂ and 2xCO₂ simulations. The daily precipitation has been modelled as a stochastic process coupled with atmospheric circulation. An automated and objective classification of daily circulation patterns (CPs) based on optimized fuzzy rules was used to classify both observed CPs and ECHAM4 GCM‐generated CPs for 1xCO₂ and 2xCO₂ climate simulations (scenarios). The coupled model ‘CP‐precipitation’ was suitable for precipitation downscaling. The overall methodology was applied to the medium‐sized mountainous Mesochora catchment in Central‐Western Greece. Results reveal substantial differences between the observed maximum daily precipitation statistical patterns and those produced by the two climate scenarios. A variable nonlinear deterministic behaviour characterizes all climate scenarios examined. Transitions’ patterns differ in terms of duration and intensity. The 2xCO₂ scenario contains the strongest transitions highlighting an unusual shift between floods and droughts. The implications of the results to the predictability of the phenomenon are also discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

联合效用理论与风险量化的防波堤决策模型研究

回顾和总结了当前防波堤项目的决策模型,介绍了效用理论的起源、发展和理论基础,提出了效用理论结合防波堤风险量化方法的新型风险决策模型.以某直立式防波堤的优化设计为例,将防波堤滑移失效概率、防波堤尺度、生命周期内的风险损失和预期收益、决策者风险态度等量化指标纳入决策系统,比较了费用最小化、费用-收益权衡和效用三种决策模型,探讨了优化设计重现期的确定.结果表明,决策者的风险态度将极大地影响防波堤方案的选择,而费用-收益模型实质上是效用模型的一种特殊情况,这凸显了效用模型的包容性和合理性.     

赤潮藻鉴定与定量检测方法进展

从基于形态学差异的图像识别技术、基于核酸分析的检测方法、基于免疫分析的检测方法、基于特征色素的方法和基于光学特性的方法5个方面,比较系统地回顾了有关赤潮藻定性鉴定和定量检测技术的发展,并就存在的问题和发展趋势作了简要分析。     

Decoupling algorithm for evaluating multiple beam damages in steel moment‐resisting frames

Post‐earthquake safety evaluation of steel moment‐resisting frames mainly relies on the inspection of seismic damage to beam–column connections. Recently, in order to evaluate seismic damage of steel connections in a prompt and precise manner, a local damage evaluation method based on dynamic strain responses has been proposed and receives attention. In the evaluation method where strain responses are measured by piezoelectric strain sensors, a strain‐based damage index has been developed for evaluating individual seismic beam damage in a steel frame. However, for a steel frame suffering multiple beam damages, the damage index deteriorates its performance in identifying small damages with the presence of neighboring severe damages because of the moment redistributions induced by larger damages. This paper presents a decoupling algorithm that removes the issue of damage interaction and improves the performance of the damage index. The decoupling algorithm was derived on the basis of damage‐induced moment release and redistribution mechanism. The effectiveness of the decoupling algorithm was numerically and experimentally investigated using a nine‐story steel frame model and a large scale five‐story steel frame testbed that can simulate multiple fractures at beam ends. Copyright © 2016 John Wiley & Sons, Ltd.     

高层抗震结构造价的改进控制模型研究——基于一恢复重建高层的实例分析

采用WSR模型分析建筑工程抗震结构造价控制问题时,存在造价控制效果差的弊端。通过设计的高层建筑工程抗震结构造价控制模型构建造价控制的递阶层次结构,获取高层建筑工程造价控制的多种方案,从多种方案中通过三标度法和权重向量法获取造价控制的最优方案;另外采用质量量化QoS调度方法进行高层建筑工程造价效益控制约束均衡设计,以获取最优方案中高层建筑工程抗震结构造价控制的结果。实验结果表明,所设计模型可有效分析高层建筑的质量化特征,可改进控制高层抗震结构工程造价,预估消耗成本可控制在1.8万元以下,且分析耗时均值为0.15 h,具有节省成本和效率快的优势,控制效果较好。     

名义上无水矿物中水的定量方法及其优缺点:FTIR方法及其存在问题

构成地幔的主要物相多是名义上无水矿物(NAMs),如橄榄石、辉石等,其晶体结构中能赋存一定量的水.水能显著地影响矿物、岩石体系的物理、化学性质乃至地球深部的许多重要地质过程.为精确获取NAMs的水含量,科学家不断开发和改进水的定量分析方法,其中傅里叶变换红外光谱法(FTIR)是测定NAMs中水含量的最主要手段,但不同研...     

Sediment yield from glacio-lacustrine calcareous deposits during the postglacial period in the Combe d’Ain (Jura,France)

The middle valley of the river Ain (Jura) cuts through glacio-lacustrine deposits laid down in an ice-dammed lake during the most recent glacial advance. The total volume eroded is about 6·21 × 10⁸ m³for a surface area of 3·7 × 10⁷ m². Erosion occurred between 18 ka BP and 6 ka BP , i.e. over a duration of some 12 ka. Sediment yield from the area was of the order of 2500 t km⁻² a⁻¹, which is comparable with modern-day sediment yield from NW African badlands. These high values are ascribed to the amenability of glacio-lacustrine deposits to mechanical weathering and to the rapid geomorphological changes that affected glacial and paraglacial sedimentary cover after the retreat of the ice. The valley slopes were destabilized by mass wasting (earthflow and mudflow), which was the predominant erosional process. The slopes are currently stabilized or very exceptionally active. © 1998 John Wiley & Sons, Ltd.     

古代玻璃材料LA-ICP-MS组分分析及产源研究

古代玻璃及玻璃质材料的定量分析对于研究其制作年代及产地、原料的来源以及制作工艺有着重要的参考意义。与电子探针(EMPA)、能谱扫描-电子显微镜(EDX-SEM)等分析方法相比,LA-ICP-MS能够快速且准确地提供样品主次量及微量元素信息。本文对LA-ICP-MS古代玻璃元素定量分析中的影响因素进行研究认为:在193nm激光下玻璃标准NIST610和康宁玻璃标准之间基体差异造成的影响较小,而采用玻璃标准NIST610为外标结合基体归一化法的校正策略测定康宁标准结果表明,该策略能够准确反映不同类型古代玻璃材料中成分组成;实验中不同剥蚀模式的研究,有助于不同实验条件的建立,从而满足不同研究的需要。本次研究对出土样品进行了分析,为该制品的产源研究提供了数据支持。