Prediction of Ambient PM10 and Toxic Metals Using Artificial Neural Networks

Abstract

In this study, an artificial neural network is employed to predict the concentration of ambient respirable particu-late matter (PM₁₀) and toxic metals observed in the city of Jaipur, India. A feed-forward network with a back-propagation learning algorithm is used to train the neural network the behavior of the data patterns. The meteorological variables of wind speed, wind direction, relative humidity, temperature, and time are taken as input to the network. The results indicate that the network is able to predict concentrations of PM₁₀ and toxic metals quite accurately.     

Interconversions and toxicity changes in hexachlorocyclohexane isomers on dispersion in water

Abstract

Studies on the transformations of hexachlorocyclohexane isomers, α‐, β‐, γ‐ and δ‐, in aqueous solution were carried out at 25 ± 1°C over a period of four weeks. Gas liquid chromatographic technique was used for analysis. The results indicated a loss as well as interconversion of all the four isomers with time. The resulting changes in toxicity of the aqueous solution were studied against Drosophila using topical application. Toxicity studies with aqueous solution of technical hexachlorocyclohexane were simultaneously carried out for comparison. Toxicity of the aqueous solutions of α‐, β‐, and δ ‐isomers showed an increase while that of the γ‐isomer decreased significantly during the four week experimental period. Aqueous solution of technical HCH was equally toxic as that of the γ‐isomer initially and did not show much decrease in its toxicity at the end. Changes in toxicity of the individual isomer solutions were considered to be due, in part, to interconversions of HCH isomers.     

基于BP神经网络的盐碱土盐分反演模型研究

土壤盐渍化是干旱,半干旱农业区主要的土地退化问题,像沙漠化一样也是当今世界重要的环境和社会经济问题.以新疆渭干河-库车河三角洲绿洲作为研究区,利用实测的盐碱土光谱数据和地下水埋深、地下水矿化度和表层土壤矿化度等因子构建了基于BP神经网络的盐碱土盐分反演模型.该模型的最终输出结果与期望得到的结果相差不大,在输出的误差中,...     

Ambient air quality and asthma cases in Niğde, Turkey

Urban air quality is one of the key factors affecting human health. Turkey has transformed itself into an urban society over the last 30 years. At the same time, air pollution has become a serious impairment to health in many urban areas in the country. This is due to many reasons. In this study, a nonparametric evaluation was conducted of health effects that are triggered by urban air pollution. Ni?de, the city which is the administrative centre of Nigde province was chosen of the effects of air pollution since, like many central Turkish cities, it is situated on a valley where atmospheric inversion occurs. In this paper, the relationship between ambient urban air quality, namely PM₁₀ and sulphur dioxide (SO₂), and human health, specifically asthma, during the winter season is examined. Air pollution data and asthma cases from 2006 to 2010 are covered in this study. The results of our study indicate that total asthma cases reported in Nigde between 2008 and 2010 were highly dependent on ambient SO₂ concentration. More asthma cases were recorded when 30 μg?m^?3 or higher SO₂ was present in the ambient air than those recorded under cleaner ambient air conditions. Moreover, it was determined that in Nigde in 2010, asthma cases reported in males aged between 45 and 64 were closely correlated with ambient SO₂ (α?=?0.05).     

Farmers’ perception of sustainable agriculture and its determinants: a case study in Kahramanmaras province of Turkey

The primary purpose of this study was to assess in quantitative terms farmers’ perceptions of sustainable agriculture and to determine how those are influenced by different socio-economic characteristics and information-seeking behavior of the farmers. The study was conducted in Kahramanmaras province of Turkey and comprised a stratified sample of 208 farmers from four districts of the province. The farmers rated each of the 21 selected sustainable agricultural practices for importance on a 5-point scale, and the total of these ratings formed the sustainable agriculture perception index. The index score was calculated for each farmer and was treated as the dependent variable in the stepwise regression analysis procedure. The independent variables were such socio-economic characteristics as the farming system, the total and irrigated area of the farm, membership of a cooperative society and participation in village administration, and age, education, and income of the farmer; components of information-seeking behavior included use of the mass media (newspapers, radio, and television), use of the Internet, travel, and participation in farming events. The results of the study showed that the higher the socio-economic status (more frequent contact with extension services, higher education, ownership of land, etc.) and the greater the access to information, the greater the perceived importance of sustainable agricultural practices. It is concluded that if policy-makers and extension organizations concentrate on these factors, they are more likely to succeed in making farmers more favorably disposed toward sustainable agriculture.     

Clinical and Environmental Surveillance of Rotavirus Common Genotypes Showed High Prevalence of Common P Genotypes in Egypt

The objective of this study was to compare the prevalence of human rotavirus group A common G and P genotypes in human Egyptian stool specimens and raw sewage samples to determine the most common genotypes for future vaccine development. From 1026 stool specimens of children with acute diarrhea and using nested RT-PCR, 250 samples (24.37%) were positive for human rotavirus group A. Using multiplex RT-PCR, rotavirus common P and G genotypes were detected as 89.20% and 46.40% of the positive clinical specimens respectively. This low percentage of common G genotypes frequency may affect the efficiency of the available live attenuated oral rotavirus vaccines [Rotarix® (human rotavirus G1P[8]) and RotaTeq® (reassortant bovine–human rotavirus G1-4P[5] and G6P[8])], however the percentage of clinical specimens which were negative for common G genotypes but positive for P[8] genotype was 12.00%. From 24 positive raw sewage samples for rotavirus group A VP6 collected from Zenin and El-Gabal El-Asfar wastewater treatment plants (WWTPs), 21 samples (87.50%) were typeable for common P genotypes while 13 samples (54.17%) were typeable for common G genotypes. Phylogenetic analysis of a VP8 partial gene of 45 P-typeable clinical isolates and 20 P-typeable raw sewage samples showed high similarity to reference strains and the majority of mutations were silent and showed lower to non-significant similarity with the two vaccine strains. This finding is useful for determining the most common antigens required for future vaccine development.

     

Hybrid power supply solutions for off-grid green wireless networks

Increasing deployment of cellular networks across the globe is pushing the energy consumption in cellular networks at an exceptional rate. The integration of renewable energy (RE) harvesting technology into future mobile networks has the potential to positively cope with environmental contamination and ensure self-energy sustainability as a means to decrease fossil fuel consumption. Diesel generator (DG) in conjunction with on-site RE harvester has emerged as an economic and extent efficient option where commercial grid supply is not viable. This paper is focused on the cost aware energy management framework addressing to least net present cost (NPC) for the envisioned hybrid powered green cellular base stations (BSs) considering tempo-spatial traffic dynamics. In such wireless networks, solar photovoltaic modules are considered as a primary energy source, while the DG and energy storage device are kept as the standby supply in case of inadequate solar energy to ensure zero outage. A comprehensive simulation-based investigation is carried out in the context of downlink Long-Term Evolution (LTE) cellular networks for evaluating cost-efficiency and reliability performance under a wide range of network settings. Particularly, this paper examines the energy yield, greenhouse gas emissions, and cost analysis based on the optimal architecture of Remote Radio Head-enabled LTE BS. Moreover, wireless network performance in terms of throughput, energy efficiency gain, and radio efficiency is thoroughly investigated using Monte Carlo simulations. Numerical results demonstrate a substantial reduction of carbon footprints with minimum NPC while satisfying the quality of service requirements.     

THE EFFECTS OF RISK AND RELIABILITY ON OPTIMAL RESERVOIR DESIGN1

A chance-constrained linear programming model, which utilizes multiple linear decision rules and is useful for river basin planning, is used to evaluate the effects of risk and reliability on optimal reservoir design. Streamflow forecasts or predictions can be explicitly included in the linear program. The risk associated with the predictions is included in the model through the use of cumulative distribution functions (CDF) of streamflows which are conditioned on the predictions. A multiple-purpose reservoir on the Gunpowder River in Maryland is used to illustrate the effectiveness of the model. In order to provide the decision makers with complete and useful information, trade-off curves relating minimum reservoir capacity (a surrogate for dam costs), water supply and flood control targets, and the reliability of achieving the targets are developed. The trade-off curves may enhance the decision maker's ability to select the best dam capacity, considering technological and financial constraints as well as the trade-offs between targets, risks, and costs.