926 resultados para Environmental information
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Salamanca, situated in center of Mexico is among the cities which suffer most from the air pollution in Mexico. The vehicular park and the industry, as well as orography and climatic characteristics have propitiated the increment in pollutant concentration of Sulphur Dioxide (SO2). In this work, a Multilayer Perceptron Neural Network has been used to make the prediction of an hour ahead of pollutant concentration. A database used to train the Neural Network corresponds to historical time series of meteorological variables and air pollutant concentrations of SO2. Before the prediction, Fuzzy c-Means and K-means clustering algorithms have been implemented in order to find relationship among pollutant and meteorological variables. Our experiments with the proposed system show the importance of this set of meteorological variables on the prediction of SO2 pollutant concentrations and the neural network efficiency. The performance estimation is determined using the Root Mean Square Error (RMSE) and Mean Absolute Error (MAE). The results showed that the information obtained in the clustering step allows a prediction of an hour ahead, with data from past 2 hours.
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Los decisores cada vez se enfrentan a problemas más complejos en los que tomar una decisión implica tener que considerar simultáneamente muchos criterios que normalmente son conflictivos entre sí. En la mayoría de los problemas de decisión es necesario considerar criterios económicos, sociales y medioambientales. La Teoría de la Decisión proporciona el marco adecuado para poder ayudar a los decisores a resolver estos problemas de decisión complejos, al permitir considerar conjuntamente la incertidumbre existente sobre las consecuencias de cada alternativa en los diferentes atributos y la imprecisión sobre las preferencias de los decisores. En esta tesis doctoral nos centramos en la imprecisión de las preferencias de los decisores cuando éstas pueden ser representadas mediante una función de utilidad multiatributo aditiva. Por lo tanto, consideramos imprecisión tanto en los pesos como en las funciones de utilidad componentes de cada atributo. Se ha considerado el caso en que la imprecisión puede ser representada por intervalos de valores o bien mediante información ordinal, en lugar de proporcionar valores concretos. En este sentido, hemos propuesto métodos que permiten ordenar las diferentes alternativas basados en los conceptos de intensidad de dominación o intensidad de preferencia, los cuales intentan medir la fuerza con la que cada alternativa es preferida al resto. Para todos los métodos propuestos se ha analizado su comportamiento y se ha comparado con los más relevantes existentes en la literatura científica que pueden ser aplicados para resolver este tipo de problemas. Para ello, se ha realizado un estudio de simulación en el que se han usado dos medidas de eficiencia (hit ratio y coeficiente de correlación de Kendall) para comparar los diferentes métodos. ABSTRACT Decision makers increasingly face complex decision-making problems where they have to simultaneously consider many often conflicting criteria. In most decision-making problems it is necessary to consider economic, social and environmental criteria. Decision making theory provides an adequate framework for helping decision makers to make complex decisions where they can jointly consider the uncertainty about the performance of each alternative for each attribute, and the imprecision of the decision maker's preferences. In this PhD thesis we focus on the imprecision of the decision maker's preferences represented by an additive multiattribute utility function. Therefore, we consider the imprecision of weights, as well as of component utility functions for each attribute. We consider the case in which the imprecision is represented by ranges of values or by ordinal information rather than precise values. In this respect, we propose methods for ranking alternatives based on notions of dominance intensity, also known as preference intensity, which attempt to measure how much more preferred each alternative is to the others. The performance of the propose methods has been analyzed and compared against the leading existing methods that are applicable to this type of problem. For this purpose, we conducted a simulation study using two efficiency measures (hit ratio and Kendall correlation coefficient) to compare the different methods.
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The Shopping centre is a long term investment in which Greenfield development decisions are often taken based on risks analysis regarding construction costs, location, competition, market and an expected DCF. Furthermore, integration between the building design, project planning, operational costs and investment analysis is not entirely considered by the investor at the decision making stage. The absence of such information tends to produce certain negative impacts on the future running costs and annual maintenance of the building, especially on energy demand and other occupancy expenses paid by the tenants to the landlord. From the investor´s point of view, this blind spot in strategy development will possibly decrease their profit margin as changes in the occupancy expenses[ ] have a direct outcome on the profit margin. In order to try to reduce some higher operating cost components such as energy use and other utility savings as well as their CO2 emissions, quite a few income properties worldwide have some type of environmental label such as BREEAM and LEED. The drawback identified in this labelling is that usually the investments required to get an ecolabel are high and the investor finds no direct evidence that it increases market value. However there is research on certified commercial properties (especially offices) that shows better performance in terms of occupancy rate and rental cost (Warren-Myers, 2012). Additionally, Sayce (2013) says that the certification only provides a quick reference point i.e. the lack of a certificate does not indicate that a building is not sustainable or efficient. Based on the issues described above, this research compares important components of the development stages such as investments costs, concept/ strategy development as well as the current investor income and property value. The subjects for this analysis are a shopping centre designed with passive cooling/bioclimatic strategies evaluated at the decision making stage, a certified regional shopping centre and a non-certified standard regional shopping centre. Moreover, the proposal intends to provide decision makers with some tools for linking green design features to the investment analysis in order to optimize the decision making process when looking into cost savings and design quality.
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Although tree ferns are an important component of temperate and tropical forests, very little is known about their ecology. Their peculiar biology (e.g., dispersal by spores and two-phase life cycle) makes it difficult to extrapolate current knowledge on the ecology of other tree species to tree ferns. In this paper, we studied the effects of negative density dependence (NDD) and environmental heterogeneity on populations of two abundant tree fern species, Cyathea caracasana and Alsophila engelii, and how these effects change across a successional gradient. Species patterns harbor information on processes such as competition that can be easily revealed using point pattern analysis techniques. However, its detection may be difficult due to the confounded effects of habitat heterogeneity. Here, we mapped three forest plots along a successional gradient in the montane forests of Southern Ecuador. We employed homogeneous and inhomogeneous K and pair correlation functions to quantify the change in the spatial pattern of different size classes and a case-control design to study associations between juvenile and adult tree ferns. Using spatial estimates of the biomass of four functional tree types (short- and long-lived pioneer, shade- and partial shade-tolerant) as covariates, we fitted heterogeneous Poisson models to the point pattern of juvenile and adult tree ferns and explored the existence of habitat dependencies on these patterns. Our study revealed NDD effects for C. caracasana and strong environmental filtering underlying the pattern of A. engelii. We found that adult and juvenile populations of both species responded differently to habitat heterogeneity and in most cases this heterogeneity was associated with the spatial distribution of biomass of the four functional tree types. These findings show the effectiveness of factoring out environmental heterogeneity to avoid confounding factors when studying NDD and demonstrate the usefulness of covariate maps derived from mapped communities.
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To successfully navigate through the environment animals rely on information concerning their directional heading and location. Many cells within the postsubiculum and anterior thalamus discharge as a function of the animal’s head direction (HD), while many cells in the hippocampus discharge in relation to the animal’s location. We placed lesions in the hippocampus and recorded from HD cells in the postsubiculum and anterior thalamus. Lesions of the hippocampus did not disrupt the HD cell signal in either brain area, indicating that the HD cell signal must be generated by structures external to the hippocampus. In addition, each cell’s preferred firing direction remained stable across days when the lesioned animal was placed into a novel environment. This stability appeared to weaken after several weeks of nonexposure to the new enclosure for two out of five animals, and subsequently recorded cells from these two animals established a new angular relationship between the familiar and novel environments. Our results suggest that extra-hippocampal structures are capable of creating and maintaining a novel representation of the animal’s environmental context. This representation shares features in common with mnemonic processes involving episodic memory that until now were assumed to require an intact hippocampus.
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Surface reactive phases of soils and aquifers, comprised of phyllosilicate and metal oxohydroxide minerals along with humic substances, play a critical role in the regulation of contaminant fate and transport. Much of our knowledge concerning contaminant-mineral interactions at the molecular level, however, is derived from extensive experimentation on model mineral systems. Although these investigations have provided a foundation for understanding reactive surface functional groups on individual mineral phases, the information cannot be readily extrapolated to complex mineral assemblages in natural systems. Recent studies have elucidated the role of less abundant mineral and organic substrates as important surface chemical modifiers and have demonstrated complex coupling of reactivity between permanent-charge phyllosilicates and variable-charge Fe-oxohydroxide phases. Surface chemical modifiers were observed to control colloid generation and transport processes in surface and subsurface environments as well as the transport of solutes and ionic tracers. The surface charging mechanisms operative in the complex mineral assemblages cannot be predicted based on bulk mineralogy or by considering surface reactivity of less abundant mineral phases based on results from model systems. The fragile nature of mineral assemblages isolated from natural systems requires novel techniques and experimental approaches for investigating their surface chemistry and reactivity free of artifacts. A complete understanding of the surface chemistry of complex mineral assemblages is prerequisite to accurately assessing environmental and human health risks of contaminants or in designing environmentally sound, cost-effective chemical and biological remediation strategies.
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L-ascorbic acid (vitamin C) is a powerful reducing agent found in millimolar concentrations in plants, and is proposed to play an important role in scavenging free radicals in plants and animals. However, surprisingly little is known about the role of this antioxidant in plant environmental stress adaptation or ascorbate biosynthesis. We report the isolation of soz1, a semi-dominant ozone-sensitive mutant that accumulates only 30% of the normal ascorbate concentration. The results of genetic approaches and feeding studies show that the ascorbate concentration affects foliar resistance to the oxidizing gas ozone. Consistent with the proposed role for ascorbate in reactive oxygen species detoxification, lipid peroxides are elevated in soz1, but not in wild type following ozone fumigation. We show that the soz1 mutant is hypersensitive to both sulfur dioxide and ultraviolet B irradiation, thus implicating ascorbate in defense against varied environmental stresses. In addition to defining the first ascorbate deficient mutant in plants, these results indicate that screening for ozone-sensitive mutants is a powerful method for identifying physiologically important antioxidant mechanisms and signal transduction pathways. Analysis of soz1 should lead to more information about the physiological roles and metabolism of ascorbate.
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This guide is written for Booz Allen Hamilton (BAH) employees assigned to the Public Lands team who may have some National Environmental Policy Act (NEPA) knowledge, possibly have experience with writing Environmental Impact Statements (EIS), and with little or no experience writing programmatic EIS documents. The guide contains information encompassing the preparation of a complete Resource Management Plan/Environmental Impact Statement (RMP/EIS) for the Bureau of Land Management. The RMP/EIS is a programmatic NEPA document which has many differences and nuances distinct from a typical project type EIS. This guide provides the information necessary for a BAH Public Lands team member to understand the project process and the RMP/EIS document to successfully maneuver through the entire project from beginning to end.
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Despite the economy, the green building industry continues to grow and drive the demand for environmentally conscious, highly skilled professionals (USGBC 2009). LEED Accredited Professionals (APs) have the knowledge and skills to meet such demand; however, information is limited regarding LEED APs or their motivations and expectations toward prospective employers. The author surveyed a sample of LEED Accredited architects and found a combination of job and personal factors motivated them to attain accreditation. LEED APs value both a competitive salary and commitment to sustainability in prospective employers. To attract, retain, and utilize LEED APs, executives in this industry must reexamine corporate culture, their willingness to pay for credentialing, and the alignment of their reputation with the desires of potential applicants.
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This paper analyses the consequences of urban environmental degradation on the well-being of Spanish miners. It is based on analyses of differences in mortality and height. The first part of the paper examines new hypotheses regarding the urban penalty. We take into consideration existing works in economic theory that address market failures when analysing the higher urban death rate. We explain the reduction in height using the model recently created by Floud, Fogel, Harris and Hong for British cities. The second part of the paper presents information demonstrating that the urban areas in the two largest mining areas in Spain (Bilbao and the Cartagena-La Unión mountain range) experienced a higher death rate relative to rural areas as a consequence of market failures derived from what we term an ‘anarchic urbanisation’.
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As human populations and resource consumption increase, it is increasingly important to monitor the quality of our environment. While laboratory instruments offer useful information, portable, easy to use sensors would allow environmental analysis to occur on-site, at lower cost, and with minimal operator training. We explore the synthesis, modification, and applications of modified polysiloxane in environmental sensing. Multiple methods of producing modified siloxanes were investigated. Oligomers were formed by using functionalized monomers, producing siloxane materials containing silicon hydride, methyl, and phenyl side chains. Silicon hydride-functionalized oligomers were further modified by hydrosilylation to incorporate methyl ester and naphthyl side chains. Modifications to the siloxane materials were also carried out using post-curing treatments. Methyl ester-functionalized siloxane was incorporated into the surface of a cured poly(dimethylsiloxane) film by siloxane equilibration. The materials containing methyl esters were hydrolyzed to reveal carboxylic acids, which could later be used for covalent protein immobilization. Finally, the siloxane surfaces were modified to incorporate antibodies by covalent, affinity, and adsorption-based attachment. These modifications were characterized by a variety of methods, including contact angle, attenuated total reflectance Fourier transform infrared spectroscopy, dye labels, and 1H nuclear magnetic resonance spectroscopy. The modified siloxane materials were employed in a variety of sensing schemes. Volatile organic compounds were detected using methyl, phenyl, and naphthyl-functionalized materials on a Fabry-Perot interferometer and a refractometer. The Fabry-Perot interferometer was found to detect the analytes upon siloxane extraction by deformation of the Bragg reflectors. The refractometer was used to determine that naphthyl-functionalized siloxanes had elevated refractive indices, rendering these materials more sensitive to some analytes. Antibody-modified siloxanes were used to detect biological analytes through a solid phase microextraction-mediated enzyme linked immunosorbent assay (SPME ELISA). The SPME ELISA was found to have higher analyte sensitivity compared to a conventional ELISA system. The detection scheme was used to detect Escherichia coli at 8500 CFU/mL. These results demonstrate the variety of methods that can be used to modify siloxanes and the wide range of applications of modified siloxanes has been demonstrated through chemical and biological sensing schemes.
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A guide to the European Union’s Environment Policy, with hyperlinks to sources of information within European Sources Online and on external websites
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Ascidians (Ascidiacea: Tunicata) are sessile suspension feeders that represent dominant epifaunal components of the Southern Ocean shelf benthos and play a significant role in the pelagic-benthic coupling. Here, we report the results of a first study on the relationship between the distribution patterns of eight common and/or abundant (putative) ascidian species, and environmental drivers in the waters off the northern Antarctic Peninsula. During RV Polarstern cruise XXIX/3 (PS81) in January-March 2013, we used seabed imaging surveys along 28 photographic transects of 2 km length each at water depths from 70 to 770 m in three regions (northwestern Weddell Sea, southern Bransfield Strait and southern Drake Passage), differing in their general environmental setting, primarily oceanographic characteristics and sea-ice dynamics, to comparatively analyze the spatial patterns in the abundance of the selected ascidians, reliably to be identified in the photographs, at three nested spatial scales. At a regional (100-km) scale, the ascidian assemblages of the Weddell Sea differed significantly from those of the other two regions, whereas at an intermediate 10-km scale no such differences were detected among habitat types (bank, upper slope, slope, deep/canyon) on the shelf and at the shelf break within each region. These spatial patterns were superimposed by a marked small-scale (10-m) patchiness of ascidian distribution within the 2-km-long transects. Among the environmental variables considered in our study, a combination of water-mass characteristics, sea-ice dynamics (approximated by 5-year averages in sea-ice cover in the region of or surrounding the photographic stations), as well as the seabed ruggedness, was identified as explaining best the distribution patterns of the ascidians.
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Question: How do interactions between the physical environment and biotic properties of vegetation influence the formation of small patterned-ground features along the Arctic bioclimate gradient? Location: At 68° to 78°N: six locations along the Dalton Highway in arctic Alaska and three in Canada (Banks Island, Prince Patrick Island and Ellef Ringnes Island). Methods: We analysed floristic and structural vegetation, biomass and abiotic data (soil chemical and physical parameters, the n-factor [a soil thermal index] and spectral information [NDVI, LAI]) on 147 microhabitat releves of zonalpatterned-ground features. Using mapping, table analysis (JUICE) and ordination techniques (NMDS). Results: Table analysis using JUICE and the phi-coefficient to identify diagnostic species revealed clear groups of diagnostic plant taxa in four of the five zonal vegetation complexes. Plant communities and zonal complexes were generally well separated in the NMDS ordination. The Alaska and Canada communities were spatially separated in the ordination because of different glacial histories and location in separate floristic provinces, but there was no single controlling environmental gradient. Vegetation structure, particularly that of bryophytes and total biomass, strongly affected thermal properties of the soils. Patterned-ground complexes with the largest thermal differential between the patterned-ground features and the surrounding vegetation exhibited the clearest patterned-ground morphologies.