玉溪市电网遭受地质灾害的风险分析

玉溪市电网覆盖比较广泛,且有高压输电线分布于地质灾害比较严重的地区,通过对地质灾害发生概率的计算和电网受到损害的概率计算,再对电网所遭受的事故损失进行综合评估来分析玉溪电网的风险程度。     

植物微体遗存分析在第四纪环境研究中的应用:综述与展望

以孢粉、植硅体等为代表的植物微体遗存由于其分布广泛,容易保存,可反映母体植物类型的优点,在第四纪环境研究中得到了广泛应用。本文介绍了植物微体遗存的概念、常见类型,以及它们的提取方法和原理,综述了利用植物微体遗存重建古环境的传统方法和近年来发展的几种古植被与古气候定量重建方法,最后简述了植物微体遗存在年代测定、稳定同位素分析研究上的应用进展与实例。文末指出了现有研究方法的问题与不足,并对今后的多代用指标的综合研究提出了展望。     

Quantifying inconsistencies in old cadastral maps and their impact on land-use reconstructions

ABSTRACT

Old cadastral maps represent a historical reference dataset for long-term land-use reconstructions. This study presents identification of inconsistencies in the nineteenth century Franziscean cadastre, one of the largest sets of old cadastral maps worldwide, by comparing three versions of the maps and written documents created in the same period. We identified all parcels and their land-use in the four sub-sources in six study areas. The overall share of inconsistencies among 5 771 identified parcels is 7.4%, with the biggest share of inconsistency in agroforestry and forestry classes. The most frequent inconsistencies are of ‘Not differentiable land use’ (n = 212) and ‘Different land-use’ categories across the sub-sources (n = 113). We conclude that the frequency of uncertainties in old cadastral maps may limit the validity of historical land-use reconstructions, affecting the eventual restoration and management efforts based on such data. We provide a summary for the use of Franziscean cadastre.     

Analysis of the global warming dynamics from temperature time series

Global warming is the observed increase of the average temperature of the Earth. The primary cause of this phenomenon is the release of the greenhouse gases by burning of fossil fuels, land cleaning, agriculture, among others, leading to the increase of the so-called greenhouse effect. An approach to deal with this important problem is the time series analysis. In this regard, different techniques can be applied to evaluate the global warming dynamics. This kind of analysis allows one to make better predictions increasing our comprehension of the phenomenon. This article applies nonlinear tools to analyze temperature time series establishing state space reconstruction and prediction. Since noise contamination is unavoidable in data acquisition, it is important to employ robust techniques. The method of delay coordinates is employed for state space reconstruction and delay parameters are evaluated using the method of average mutual information and the method of false nearest neighbors. Afterwards, the simple nonlinear prediction method is employed to estimate temperatures of the future. Temperature time series from different places of the planet are used. Initially, the approach is verified considering known parts of the time series and afterwards, results are extrapolated for future values estimating temperature until 2028. Results show that these techniques are interesting to estimate temperature time history, presenting coherent estimations.     

基于层次分析法的电网建设承(分)包商安全施工承载力评估

如何有针对性地对承(分)包商的安全施工承载力进行评估,已逐渐成为影响电网建设分包管理的重要因素。运用层次分析法,构建电网建设承(分)包商安全施工承载力分析模型,直观观察各影响因素权重,对加强承(分)包商的管理、探究分包管理机制、开展安全管理工作具有一定的指导意义。     

Numerical Prediction of Dispersion Characteristics in an Urban Area Based on Grid Refinement and Various Turbulence Models

A detailed simulation of the Goettinger Strasse pollutantdispersion problem is performed using the CFD code CFX-TASCflow for different wind directions. Two turbulencemodels, the k- and the RSM are adopted on three gridrefinement levels. Besides the typical reference gridimplemented by the TRAPOS group, two different gridresolutions are introduced. The first refinement is in thewhole street canyon region on the x-y level, while thesecond one is local in all three directions. Validation ofall involved computational schemes is performed based onrelative available experimental data. The computed velocityfields and concentration contours imply that the typicalreference grid is a suitable choice for the velocityfields, while local grid refinement in all three directionsin a small region containing the receptor is required toupgrade the pollutant concentration results with modestadditional computational effort. Finally the RSM modelresulted in smaller concentration levels. The k-model compared to the RSM seems a more appropriate choiceto solve this particular problem.     

边坡变形时序非线性判定及混沌预测研究

以探讨边坡变形性质及混沌预测可行性为目的,基于混沌理论利用相空间重构技术对其变形时间序列进行混沌特征判定,试验显示变形系统具有混沌特性,可用混沌相关理论进行研究;基于混沌相空间重构技术,笔者构建了多种混沌预测模型进行混沌预计研究,分析各类模型的工程实际应用效果;针对单次监测时序预测精度较低的问题,提出累加时序预测方案,训练结果显示,短期预测精度变形累计值基本控制在5%以内,高程值预测相对误差均低于1%,预测精度较高,可以用于工程实际。     

Automated energy management in distributed electricity systems: An EEPOS approach

The increasing capacity of distributed electricity generation brings new challenges in maintaining a high security and quality of electricity supply. New techniques are required for grid support and power balance. The highest potential for these techniques is to be found on the part of the electricity distribution grid.

This article addresses this potential and presents the EEPOS project’s approach to the automated management of flexible electrical loads in neighborhoods. The management goals are (i) maximum utilization of distributed generation in the local grid, (ii) peak load shaving/congestion management, and (iii) reduction of electricity distribution losses. Contribution to the power balance is considered by applying two-tariff pricing for electricity.

The presented approach to energy management is tested in a hypothetical sensitivity analysis of a distribution feeder with 10 households and 10 photovoltaic (PV) plants with an average daily consumption of electricity of 4.54 kWh per household and a peak PV panel output of 0.38 kW per plant. Energy management shows efficient performance at relatively low capacities of flexible load. At a flexible load capacity of 2.5% (of the average daily electricity consumption), PV generation surplus is compensated by 34–100% depending on solar irradiance. Peak load is reduced by 30% on average. The article also presents the load shifting effect on electricity distribution losses and electricity costs for the grid user.     

化学纤维栅湿式过滤除尘的实验研究

化学纤维栅湿式除尘是一种复合机理的新型湿式过滤除尘技术,其过滤风速为2～10m/s,阻力仅为200～500Pa,除尘效率达到99.62％,能很好解决矿山溜井卸矿产生的粉尘,使溜井含尘气流经净化后达到新鲜风流卫生标准。     

基于重构相空间充填体变形规律的灰色预测研究

尾砂胶结充填体是非线性力学介质,其变形是能量耗散的复杂过程,必须研究其内在变形规律,才能正确预测采矿过程中充填体的稳定性.对不同配比的尾砂胶结充填体进行力学试验,得出了其应力-应变规律,对安庆铜矿高阶段充填体变形进行了监测.采用自适应滤波原理,研究基于重构相空间的测量数据去噪处理方法.用灰色理论研究充填体变形在相空间中相点距离的演变规律,建立了重构相空间的灰色预测模型.为减小预测误差,对预测结果采用残差模型修正.应用建立的模型,对安庆铜矿高阶段充填体变形进行分析,确定了采场合理回采周期.结果表明,充填体变形具有非线性混沌特性,不同配比的充填体表现出不同的非线性动力学行为,重构相空间能充分展示充填体变形的内在规律.