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251.
Solid waste prediction is crucial for sustainable solid waste management. Usually, accurate waste generation record is challenge in developing countries which complicates the modelling process. Solid waste generation is related to demographic, economic, and social factors. However, these factors are highly varied due to population and economy growths. The objective of this research is to determine the most influencing demographic and economic factors that affect solid waste generation using systematic approach, and then develop a model to forecast solid waste generation using a modified Adaptive Neural Inference System (MANFIS). The model evaluation was performed using Root Mean Square Error (RMSE), Mean Absolute Error (MAE) and the coefficient of determination (R2). The results show that the best input variables are people age groups 0-14, 15-64, and people above 65 years, and the best model structure is 3 triangular fuzzy membership functions and 27 fuzzy rules. The model has been validated using testing data and the resulted training RMSE, MAE and R2 were 0.2678, 0.045 and 0.99, respectively, while for testing phase RMSE =3.986, MAE = 0.673 and R2 = 0.98.

Implications: To date, a few attempts have been made to predict the annual solid waste generation in developing countries. This paper presents modeling of annual solid waste generation using Modified ANFIS, it is a systematic approach to search for the most influencing factors and then modify the ANFIS structure to simplify the model. The proposed method can be used to forecast the waste generation in such developing countries where accurate reliable data is not always available. Moreover, annual solid waste prediction is essential for sustainable planning.  相似文献   
252.
Metal levels in fish have been extensively studied, but little data currently exists for the Middle East. We examined the levels of metals and metalloids (aluminum, arsenic, copper, manganese, selenium, zinc, and mercury) in the flesh of 13 fish species collected from three fishing sites and a local fish market in Jeddah, Saudi Arabia. We tested the following null hypotheses: (1) there are no interspecific differences in metal levels, (2) there are no differences in metal levels in fishes between market and fishing sites, (3) there are no size-related differences in metal levels, and (4) there are no differences in selenium:mercury molar ratio among different fish species. There were significant interspecific differences in concentrations for all metals. There was an order of magnitude difference in the levels of aluminum, arsenic, mercury, manganese, and selenium, indicating wide variation in potential effects on the fish themselves and on their predators. Fishes from Area II, close to a large commercial port, had the highest levels of arsenic, mercury, and selenium, followed by market fishes. Mercury was positively correlated with body size in 6 of the 13 fish species examined. Mercury was correlated positively with arsenic and selenium, but negatively with aluminum, cobalt, copper, manganese, and zinc. Selenium:mercury molar ratios varied significantly among species, with Carangoides bajad, Cephalopholis argus, Variola louti, and Ephinephelus tauvina having ratios below 10:1. These findings can be used in risk assessments, design of mercury reduction plans, development of fish advisories to protect public health, and future management decision-making.  相似文献   
253.
In 2010, a magnitude 7.0 earthquake struck Haiti, severely damaging the drinking and wastewater infrastructure and leaving millions homeless. Compounding this problem, the introduction of Vibrio cholerae resulted in a massive cholera outbreak that infected over 700,000 people and threatened the safety of Haiti’s drinking water. To mitigate this public health crisis, non-government organizations installed thousands of wells to provide communities with safe drinking water. However, despite increased access, Haiti currently lacks the monitoring capacity to assure the microbial safety of any of its water resources. For these reasons, this study was designed to assess the feasibility of using a simple, low-cost method to detect indicators of fecal contamination of drinking water that could be implemented at the community level. Water samples from 358 sources of drinking water in the Léogâne flood basin were screened with a commercially available hydrogen sulfide test and a standard membrane method for the enumeration of thermotolerant coliforms. When compared with the gold standard method, the hydrogen sulfide test had a sensitivity of 65 % and a specificity of 93 %. While the sensitivity of the assay increased at higher fecal coliform concentrations, it never exceeded 88 %, even with fecal coliform concentrations greater than 100 colony-forming units per 100 ml. While its simplicity makes the hydrogen sulfide test attractive for assessing water quality in low-resource settings, the low sensitivity raises concerns about its use as the sole indicator of the presence or absence of fecal coliforms in individual or community water sources.  相似文献   
254.
The present study aims to evaluate the competitive biosorption of lead, cadmium, copper, and arsenic ions by using native algae. A series of experiments were carried out in a batch reactor to obtain equilibrium data for adsorption of single, binary, ternary, and quaternary metal solutions. The biosorption of these metals is based on ion exchange mechanism accompanied by the release of light metals such as calcium, magnesium, and sodium. Experimental parameters such as pH, initial metal concentrations, and temperature were studied. The optimum pH found for removal were 5 for Cd2+ and As3+ and 3 and 4 for Pb2+ and Cu2+, respectively. Fourier transformation infrared spectroscopy analysis was used to find the effects of functional groups of algae in biosorption process. The results showed that Pb2+ made a greater change in the functional groups of algal biomass due to high affinity to this metal. An ion exchange model was found suitable for describing the biosorption process. The affinity constants sequence calculated for single system was K Pb > K Cu > K Cd > K As; these values reduced in binary, ternary, and quaternary systems. In addition, the experimental data showed that the biosorption of the four metals fitted well the pseudo-second-order kinetics model.  相似文献   
255.
The objective of this study was to determine whether the fear of dioxin/furan emissions from waste-to-energy plants was justified by the 2007 status of emissions of French municipal solid waste incinerators (MSWIs). All emissions were examined, plant by plant, but this paper focuses on the incinerator emission that is most frequently mentioned in the French media, toxic dioxins and furans. The study showed that there are 85 large MSWI that generate electricity or heat, i.e., waste-to-energy (WTE) plants, and 39 smaller MSW incinerators. The results showed that all French MSWI are operated well below the EU and French standard of 0.1 ng TEQ Nm?3 (toxic equivalent nanograms per standard cubic meter) and that their total dioxin/furan emissions decreased from 435 g TEQ in 1997 to only 1.2 g in 2008. All other industrial emissions of dioxins have also decreased and the major source is residential combustion of wood (320 g TEQ). It was extremely difficult to obtain MSWI emission data. This unwarranted lack of transparency has resulted in the public perception that MSWI plants are major contributors to dioxin emissions while in fact they have ceased to be so.  相似文献   
256.
Kuwait Bay is an imperative characteristic of the State of Kuwait. It has a number of major activities existing around it, including, business, industrial and recreational ones. The phase of construction and development of projects, and their resulting pollution have led to major change in the features of the area. The purpose of this research is to serve as a managing tool for decision-making through the environmental assessment of Kuwait Bay. Due to the multiplicities and diversities of the man-made activities and the natural environmental setting of the bay, the impacts are out looked on a holistic approach rather than on a single approach. The methodology of assessment including, sampling and analysis of water and sediment, statistical analysis, as well as application of the Rapid Impact Assessment Matrix (RAIM) in order to analysis the impacts in an integrated approach. The southern areas of the bay are the main sources of pollution that distributed northward to cover the central region of the bay. Sulaibikhat Bay (South-West sector of the bay) is the most vulnerable area due to its exposure to anthropogenic activities such as reclamations, sewage inflow and other activities. The area near Shuwaikh Port is suffering due to reclamation processes. The northern and north-west sectors suffer from coastal erosion as well as from pollutants arriving via Shatt Al Arab.  相似文献   
257.
The current study was aimed to investigate the impact of THI on productive and reproductive indices of PE and F1 crosses (50% PE and 50% Italian buffaloes) and back crosses (BC) (75% PE and 25% Italian buffaloes) under hot conditions. In this study, 8385 records used PE (1914, 1518, and 1737), F1 (387, 447, and 657), and BC (495, 585, and 645) for low, medium, and high THI, respectively. The high THI reduced the conception rate after first insemination in PE, F1, and BC ((odds ratio, OR) = 1.187, P = 0.007; 2.361, <0.0001 and 1.603, <0.0001, respectively) when compared with low THI. But, stillbirth and calving condition were not significantly influenced by different THI levels in BC and F1. BC was more bearable to the harsh environment; they possessed the highest incidence of conception after first insemination (72.70, 72.60, and 62.40%), producing live calves (98.50, 100, and 99.40%) with easy calving condition (98.50, 100, and 99.40%) when compared to PE and F1 at different levels of THI, respectively. The average daily milk yield and peak of milk production were decreased in PE (4.02 and 5.12%), BC (13.33 and 10.95%), and F1 (25.29 and 12.20%) from low to high THI. However, BC revealed no significant changes in days open, dry period, calving interval, gestation length, service per conception, and the first service post-partum at different levels of THI when compared with PE and F1. Therefore, rearing BC is recommended for improving buffalo productive and reproductive performance under hot conditions.  相似文献   
258.
Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse?1, 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20–500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01–0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results.  相似文献   
259.
260.
Debate and literature on the link between degrading environments and human mobility has been increasing exponentially. There is little concrete evidence, however, of efforts or policies that support the management of environmentally influenced mobility. Through discourse analysis using Q-methodology, this research aimed to scrutinize the standoff between opposing views under a fresh lens. One-hundred and ninety-seven experts from 49 nations completed an on-line survey asking them to sort, by level of agreement, 42 statements gleaned from the literature concerning the environment-mobility nexus. Four very different discourses emerged: determined humanists, benevolent pragmatists, cynical protectionists, and critical realists. The complexity of these discourses helps explain the stalemate while confirming the inappropriateness of one-sided terminology and linear quantifications. Despite diametrically opposed viewpoints, experts unanimously agree that human mobility is connected to environmental change. Dissection of these social perspectives builds a new foundation for the Rio+20 analysis and policy deliberations related to environmentally influenced human mobility.  相似文献   
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