Effect of quarry dust addition on the performance of controlled low-strength material made from industrial waste incineration bottom ash

The performance of industrial waste incineration bottom ash in controlled low-strength material (CLSM) was investigated in this paper, as the quarry dust was added. CLSM mixtures were made from the industrial waste incineration bottom ash, quarry dust, and cement. Tests for fresh density, bleeding, compressive strength, shear strength, hydraulic conductivity, and excavatability were carried out. The compressive strength ranges from 60 kPa to 6790 kPa, the friction angle varies from 5° to 19°, and the cohesion is from 4 to 604 kPa. Most of the mixtures are found to be non-excavatable. It is indicated that the quarry dust addition increases the compressive strength and shear parameters, decreases bleeding, and increases the removability modulus.     

Forecasting the federal budget with time-series models

The stochastic properties of conventionally denned federal expenditures and revenues are examined, and cointegration is found. Alternative time-series models-univariate ARIMA models, vector autoregressions in levels and differences, and an error correction model-are specified and estimated using quarterly data from 1955:1 through 1979:4. Updated forecasts for up to three years beyond the sample period are evaluated against actual expenditures, revenues and the deficit. The vector autoregression in levels shows evidence of nonstationarity, which leads to strong biases in the forecasts. The remaining models produce forecasts that are satisfactory by the mean squared error criterion, and the magnitudes of biases at the longer horizons are significantly smaller than those of the official forecasts.     

伊朗食虫虻（双翅目：食虫虻科）的猎物记录

本文根据伊朗食虫虻科AsiLidae的文献资料，记录了伊朗104种食虫虻的130种猎物。这些猎物隶属昆虫纲Insecta的7个目（膜翅目Hymenoptera，双翅目Diptera，鞘翅目CoLeoptera，直翅目Orthoptera，鳞翅目Lepidoptera，半翅目异翅亚目Heteroptera和脉翅目Neuroptera）37科，此外，还有1种蜘蛛也是食虫虻的猎物。     

Assessment of deterioration in RHA-concrete due to magnesium sulphate attack

The assessment of magnesium sulphate attack on concretes containing rice husk ash (RHA, 20wt% of the cementitious materials) with various average particle sizes was investigated. The total cementitious materials were 390 kg and the water-to-binder ratio (W/B) was 0.53 for all mixtures. Specimens were initially cured in water for 7 d and then immersed in the 3wt% magnesium sulphate solution for up to 111 d of exposure. The specimens were subjected to drying-wetting cycles to accelerate sulphate attack. In addition to the visual monitoring of the specimens, the concrete specimens were subsequently tested for compressive strength, dynamic modulus of elasticity, and length and mass changes. The results show that the specimens exposed to sulphate attack exhibit higher strength and dynamic modulus than those kept in water. The length change is negligible and can be attributed to the normal swelling of concrete. On the other hand, concretes suffers mass loss and surface spalling and softening; the fine RHA-concrete results in a better resistance. For the accelerated sulphate attack method used in this study, mass change and visual monitoring are recommended for assessing the deterioration degree and the effectiveness of supplementary cementitious materials to resist sulphate attack.     

Evaluation of charge storage ability of chrome doped Mn2O3 nanostructures derived by cathodic electrodeposition

A facile synthetic route has been proposed to prepare cauliflower-like nanostructures of Cr doped Mn2O3. The synthesis was carried out by constant current cathodic electrodeposition from Mn2+ nitrate solutions containing minor amounts of dichromate. It was found that the presence of Cr mediates the formation of cathodic MnO2 which then reacts with the excess Mn2+ species to form Mn2O3 nanostructures. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Differential Thermal Analysis (DTA) were used to characterize the nanostructures. The storage ability of the obtained nanostructures was investigated by cyclic voltammetry (CV) in 0.5 M Na2SO4 solution. The results indicated that the Cr doped manganese oxide material shows better performance than the non-doped one, and the charge capacity (SC) of doped manganese oxide (218 F/g) was higher than pure manganese oxide (208 F/g).     

于田绿洲耕地变化驱动机制研究

根据于田绿洲耕地变化和相关的社会经济状况及其变化特征的典型相关分析，提出了表征耕地变化及其驱动因素的指标，分析了两者的相关性及探讨了人口变化驱动因素对耕地变化的驱动机制，为协调干旱区土地资源和人类活动的关系提供依据，为进一步进行绿洲土地利用变化研究积累方法和经验。图4，表2，参16。     

Geosensing systems engineering for ocean security and sustainable coastal zone management

<正>Three major threats to ocean security and coastal zone sustainability - global warming,the loss of ocean biodiversity,and pollution - are combining to threaten the ecological integrity of our marine environment and life support systems.We put forward a geomatics-based systems engineering architecture to identify the location and extent of oil spills,thereby improving the ecological integrity of the world's oceans and helping contingency planners to determine required assets,personnel and other resources.This real-time,event-based and cost effective emergency management decision support system can aid in the classification,detection,and monitoring of oil spills in the marine environment.The developed Synthetic-Aperture Radar(SAR) processing and calibration techniques efficiently monitor environmental changes in inaccessible ocean regions,characterize oil spill scenarios,and help to identify spill sources.The system is used to improve emergency management in the Gulf of Mexico,with application to oil spills arising from Hurricane Katrina.     

Wind power prediction based on wind speed forecast using hidden Markov model

This study examines a new approach for short-term wind speed and power forecasting based on the mixture of Gaussian hidden Markov models (MoG-HMMs). The proposed approach focuses on the characteristics of wind speed and power in the consecutive hours of previous days. The proposed method is carried out in two steps. In the first step, for the hourly prediction of wind speed, several wind speed features are employed in MoG-HMM, and in the second step, the results obtained from the first step along with their characteristics and wind power features are used to predict wind power estimation. To increase the prediction accuracy, the data used in each step are classified, and then for each class, one HMM with its specific parameters is used. The performance of the proposed approach is examined using real NREL data. The results show that the proposed method is more precise than other examined methods.     

空间-时间编码的理论与实践

在大多数未来的无线通讯系统中使用多架天线似乎是不可避免的。现在主要的问题是容纳多架天线以什么是对于具体应用最合适的方法。对于空间一时间和多端输人多端输出（MIMO）系统的学术兴趣在过去的几年中逐渐形成。近来工业界也表示出了许多的兴趣。这个课题是怎样很快地从一个理论上的好奇变成了该领域中每一个工程师的实践，