168 resultados para Apportionment


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This project was the first comprehensive assessment of heavy metals to be conducted in the sediments of Northern Moreton Bay since the 1970s and found that shipping and shipping related activities contributed significantly to the level of sediment contamination in the area. The study was also used to develop and test new methods of assessing heavy metal sediment quality.

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The role of different chemical compounds, particularly organics, involved in the new particle formation (NPF) and its consequent growth are not fully understood. Therefore, this study was conducted to investigate the chemical composition of aerosol particles during NPF events in an urban subtropical environment. Aerosol chemical composition was measured along with particle number size distribution (PNSD) and several other air quality parameters at five sites across an urban subtropical environment. An Aerodyne compact Time-of-Flight Aerosol Mass Spectrometer (c-TOF-AMS) and a TSI Scanning Mobility Particle Sizer (SMPS) measured aerosol chemical composition (particles above 50 nm in vacuum aerodynamic diameter) and PNSD (particles within 9-414 nm in mobility diameter), respectively. Five NPF events, with growth rates in the range 3.3-4.6 nm, were detected at two of the sites. The NPF events happened on relatively warmer days with lower condensation sink (CS). Temporal percent fractions of organics increased after the particles grew enough to have a significant contribution to particles volume, while the mass fraction of ammonium and sulphate decreased. This uncovered the important role of organics in the growth of newly formed particles. Three organic markers, factors f43, f44 and f57, were calculated and the f44 vs f43 trends were compared between nucleation and non-nucleation days. K-means cluster analysis was performed on f44 vs f43 data and it was found that they follow different patterns on nucleation days compared to non-nucleation days, whereby f43 decreased for vehicle emission generated particles, while both f44 and f43 decreased for NPF generated particles. It was found for the first time that vehicle generated and newly formed particles cluster in different locations on f44 vs f43 plot and this finding can be potentially used as a tool for source apportionment of measured particles.

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This study addresses three important issues in tree bucking optimization in the context of cut-to-length harvesting. (1) Would the fit between the log demand and log output distributions be better if the price and/or demand matrices controlling the bucking decisions on modern cut-to-length harvesters were adjusted to the unique conditions of each individual stand? (2) In what ways can we generate stand and product specific price and demand matrices? (3) What alternatives do we have to measure the fit between the log demand and log output distributions, and what would be an ideal goodness-of-fit measure? Three iterative search systems were developed for seeking stand-specific price and demand matrix sets: (1) A fuzzy logic control system for calibrating the price matrix of one log product for one stand at a time (the stand-level one-product approach); (2) a genetic algorithm system for adjusting the price matrices of one log product in parallel for several stands (the forest-level one-product approach); and (3) a genetic algorithm system for dividing the overall demand matrix of each of the several log products into stand-specific sub-demands simultaneously for several stands and products (the forest-level multi-product approach). The stem material used for testing the performance of the stand-specific price and demand matrices against that of the reference matrices was comprised of 9 155 Norway spruce (Picea abies (L.) Karst.) sawlog stems gathered by harvesters from 15 mature spruce-dominated stands in southern Finland. The reference price and demand matrices were either direct copies or slightly modified versions of those used by two Finnish sawmilling companies. Two types of stand-specific bucking matrices were compiled for each log product. One was from the harvester-collected stem profiles and the other was from the pre-harvest inventory data. Four goodness-of-fit measures were analyzed for their appropriateness in determining the similarity between the log demand and log output distributions: (1) the apportionment degree (index), (2) the chi-square statistic, (3) Laspeyres quantity index, and (4) the price-weighted apportionment degree. The study confirmed that any improvement in the fit between the log demand and log output distributions can only be realized at the expense of log volumes produced. Stand-level pre-control of price matrices was found to be advantageous, provided the control is done with perfect stem data. Forest-level pre-control of price matrices resulted in no improvement in the cumulative apportionment degree. Cutting stands under the control of stand-specific demand matrices yielded a better total fit between the demand and output matrices at the forest level than was obtained by cutting each stand with non-stand-specific reference matrices. The theoretical and experimental analyses suggest that none of the three alternative goodness-of-fit measures clearly outperforms the traditional apportionment degree measure. Keywords: harvesting, tree bucking optimization, simulation, fuzzy control, genetic algorithms, goodness-of-fit

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Attention is given to the results of optimization studies with a 16-micron CO2-N2-H2 GDL employing two-dimensional wedge nozzles. The optimum value of the achievable gain reaches 12.7 percent/cm on the P(15) line for a 30:50:20 percent respective apportionment of the aforementioned gases. The corresponding optimum values for reservoir pressure and area ratio are computed as functions of reservoir temperature, and presented graphically.

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Prescribed burnings are conducted in Queensland each year from August until November aiming to decrease the impact of bushfire hazards and maintain the health of vegetation. This study reports chemical characteristics of the ambient aerosol, with a focus on source apportionment of the organic aerosol (OA)fraction, during the prescribed biomass burning (BB) season in Brisbane 2013. All measurements were conducted within the International Laboratory for Air Quality and Health (ILAQH) located in Brisbane’s Central Business District. Chemical composition, degree of ageing and the influence of BB emission on the air quality of central Brisbane were characterized using a compact Time of Flight Aerosol Mass Spectrometer (cToF-AMS). AMS loadings were dominated by OA (64 %), followed by, sulfate (17 %), ammonium (14 %) and nitrates (5 %). Source apportionment was applied on the AMS OA mass spectra via the multilinear engine solver (ME-2) implementation within the recently developed Source Finder (SoFi) interface. Six factors were extracted including hydrocarbon-like OA (HOA), cooking-related OA (COA), biomass burning OA (BBOA), low-volatility oxygenated OA (LV-OOA), semivolatile oxygenated OA (SV-OOA), and nitrogen-enriched OA (NOA). The aerosol fraction that was attributed to BB factor was 9 %, on average over the sampling period. The high proportion of oxygenated OA (72 %), typically representing aged emissions, could possess a fraction of oxygenated species transformed from BB components on their way to the sampling site.

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Trata-se de estudo dirigido à afirmação da natureza objetiva da responsabilidade objetiva da Administração Pública por atos omissivos. Defende-se a correta aplicação do artigo 37 parágrafo 6 da Constituição da República, em que se fora estabelecida a responsabilidade objetiva da Administração em todas as hipóteses em que esteja configurado nexo causal entre sua atuação, comissiva ou omissiva, e um dano injusto ocorrido. É novo o enfoque que norteia a reparação civil, não mais a atividade realizada pelo agente, mas as conseqüências sofridas pela vítima deste dano injusto. Exercitada na seara da responsabilidade civil do Estado, considerado em sentido lato, parece ainda mais lógica a mudança de enfoque mencionada, em razão do princípio norteador do seu dever de reparar, que é o da repartição eqüitativa dos encargos da Administração. De fato, sempre que a atividade administrativa estatal, exercida em benefício de toda a coletividade, gerar dano injusto a um particular específico, configurar-se-á sua responsabilidade de reparar este dano, já que, se é em nome da coletividade que se adotou a conduta geradora do dano, esta a idéia principal daquela diretriz enunciada. Daí por que a verificação da presença do elemento subjetivo culpa, em sede de responsabilidade do Poder Público, fora tornada inteiramente estranho ao exame. A correta leitura do artigo constitucional, com reconhecimento da responsabilidade objetiva do Estado nas hipóteses de ato comissivo e omissivo da Administração Pública, realiza, ainda, o princípio da solidariedade social, que implica preponderância do interesse da reparação da vítima lesada sobre o interesse do agente que realiza, comissiva ou omissivamente, o ato lesivo. Essa a legitimidade da teoria do risco administrativo adotada, a adoção de coerente verificação do nexo causal, com admissão da oposição de excludentes de responsabilidade. Ademais, entre a vítima e o autor do dano injusto, a primeira não obtém, em geral, beneficio algum com o fato ou a atividade de que se originou o dano. Se assim é, a configuração do dever de indenizar da Administração Pública dependerá, apenas, da comprovação, no caso concreto, de três pressupostos que se somam: a atuação do Estado, a configuração do dano injusto e o nexo de causalidade. Será referida a jurisprudência espanhola consagrada à regra de responsabilidade objetiva da Administração Pública por atos omissivos, com considerações acerca da resposta da Jurisprudência daquele país ao respectivo enunciado normativo. Buscou-se, desta forma, elencar-se os elementos básicos à compreensão do tema, e também os pressupostos essenciais à afirmação da natureza objetiva da responsabilidade da Administração Pública por atos omissivos, que são, primordialmente, a compreensão do fundamento da regra constitucional, a correta delimitação do conceito de omissão e de causalidade omissiva. Destacados os pressupostos necessários à correta compreensão do tema, conclui-se pela afirmação da natureza objetiva da responsabilidade da Administração Pública por dano injusto advindo de ato omissivo, desde que assim o seja, querendo-se significar, desta forma, que a responsabilidade mencionada não prescinde da configuração do nexo causal entre o comportamento omissivo ocorrido e o dano injusto que se quer reparar.

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In elections voters have generally four options: to abstain, to cast a blank vote, to cast a null vote, or to vote for a candidate or party. This last option is a positive expression of support, while the other three options reflect lack of interest, or dissatisfaction with the parties or the political system. However only votes for parties or candidates are taken into account in the apportionment method. In particular the number of seats allocated to parties remains constant even if the number of non votes (i.e. blank votes, null votes or abstention) is very large. This paper proposes to treat the non votes as a party in the apportionment method and to leave empty the corresponding seats. These empty seats are referred to as "ghost seats". How this would affect the decision-making is quantified in terms of power indices. We apply this proposal to a case study:the regional Parliament of the Basque Autonomous Community (Spain) from 1980 till 2012.

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A federação é uma forma de Estado adotada modernamente por mais de trinta Países, e consiste numa divisão territorial do poder entre um governo central e governos locais. No Brasil, esta divisão contempla um poder local-estadual e um poder local-municipal. A federação é assimétrica quando aos entes de mesmo nível (local-estadual ou local-municipal) são atribuídos diferentes regimes jurídicos, para compensar ou equilibrar suas diversidades. O chamado federalismo fiscal estuda as receitas e despesas dos entes que integram um Estado federal. No Brasil, sempre se adotou a simetria entre os municípios. Após a análise da posição do município brasileiro na questão fiscal (receitas, encargos e formas de redistribuição de recursos), identificam-se quatro pontos passíveis de mudança normativa, para seu aperfeiçoamento: brecha vertical, guerra fiscal, critérios para criação de municípios e regiões metropolitanas. As propostas formuladas na tese são: a mudança do paradigma da simetria, instituindo-se um regime especial para os municípios com população inferior a dez mil habitantes; a proibição de que sejam criados novos municípios com este porte; novos critérios e procedimentos para criação de municípios; instituição de um conselho de municípios, junto ao Senado Federal; nova forma de rateio do fundo de participação dos municípios, com a criação do fundo de participação das regiões metropolitanas; a serem criadas pela União e geridas através de conselhos formados pelos municípios e Estados-membros participantes, na proporção de sua população, área e economia.

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This is the Gunnislake Fish Counter Annual Report 2002 from the Environment Agency South West Region, which was held on March 2002. It presents the daily upstream counts of migratory salmonids recorded on the River Tamar at Gunnislake Weir fish counting station in 2002. The data within this report covers the period of the commercial migratory salmonid net buy-back scheme and the National Spring Salmon Bylaws. The report contains section on Net Buy-Back; Species Apportionment; Validation of counter efficiency; results as total number of migratory salmonid (salmon and Sea Trout) counted moving upstream in 2002 at Gunnislake; video validation and Counter Efficiency; and Discussion. The section Discussion includes Salmon and Sea Trout counts recorded on the River Tamar 1995-2002, other fish species observed as sea lamprey and Environmental Factors (river flows, water temperature, and barometric pressure).

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This is a technical report on the assessment of the hydrogeological impacts of aggregate extraction activities in the Delamere Area, Cheshire. The first aim of the study was to carry out Stage 3-appropriate assessment, under the EU Habitats Directive (92/43/EEC), of the possible hydrogeological impacts of aggregate extraction activities authorised by the Cheshire CC on candidate Special Areas of Conservation (cSAC) on the Delamere sandsheet, Cheshire. Identifying possible impacts if these activities on the hydrogeological environment, construction of a numerical groundwater flow model of the groundwater system to investigate and quantify impacts and to produce a report as required under Stage 3 of the Habitats Regulations. Secondly, to identify the future potential impacts of the continued extraction of sand and gravel reserves from above and below the water tables from within the Delamere sandsheet, thus releasing reserves identified within the Area of Search of the Cheshire Replacement Minerals Local Plan 1999. This aspect of the study should assist in identifying the implications of further working within Delamere for North West sub-regional apportionment.

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The paper develops the basis for a self-consistent, operationally useful, reactive pollutant dispersion model, for application in urban environments. The model addresses the multi-scale nature of the physical and chemical processes and the interaction between the different scales. The methodology builds on existing techniques of source apportionment in pollutant dispersion and on reduction techniques of detailed chemical mechanisms. © 2005 Published by Elsevier Ltd.

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In this paper, source apportionment techniques are employed to identify and quantify the major particle pollution source classes affecting a monitoring site in metropolitan Boston, MA. A Principal Component Analysis (PCA) of paniculate elemental data allows the estimation of mass contributions for five fine mass panicle source classes (soil, motor vehicle, coal related, oil and salt aerosols), and six coarse panicle source classes (soil, motor vehicle, refuse incineration, residual oil, salt and sulfate aerosols). Also derived are the elemental characteristics of those source aerosols and their contributions to the total recorded elemental concentrations (i.e. an elemental mass balance). These are estimated by applying a new approach to apportioning mass among various PCA source components: the calculation of Absolute Principal Component Scores, and the subsequent regression of daily mass and elemental concentrations on these scores.

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Xanthoria parietina, common foliose lichen, growing in its natural habitat, was analysed for the concentration of five heavy metals (Fe, Cr, Zn, Pb and Cu) from different forest sites of North East of Morocco (Kenitra, Sidi Boughaba, Mkhinza, Ceinture Verte near Temara city, Skhirate, Bouznika and Mohammedia). The quantification was carried out by inductively coupled plasma - atomic emission spectrometry (ICP-AES). Results were highly significant p<0,001. The concentration of metals is correlated with the vehicular activity and urbanization. The total metal concentration is highest at the Kenitra area, followed by Ceinture Verte site near Temara city, which experience heavy traffic throughout the year. Scanning electron microscopy (SEM) of particulate matter on lichen of Xanthoria parietina was assessed as a complementary technique to wet chemical analysis for source apportionment of airborne contaminant. Analysis revealed high level of Cu, Cr, Zn and Pb in samples near roads.  

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In Portugal, it was estimated that around 1.95 Mton/year of wood is used in residential wood burning for heating and cooking. Additionally, in the last decades, burnt forest area has also been increasing. These combustions result in high levels of toxic air pollutants and a large perturbation of atmospheric chemistry, interfere with climate and have adverse effects on health. Accurate quantification of the amounts of trace gases and particulate matter emitted from residential wood burning, agriculture and garden waste burning and forest fires on a regional and global basis is essential for various purposes, including: the investigation of several atmospheric processes, the reporting of greenhouse gas emissions, and quantification of the air pollution sources that affect human health at regional scales. In Southern Europe, data on detailed emission factors from biomass burning are rather inexistent. Emission inventories and source apportionment, photochemical and climate change models use default values obtained for US and Northern Europe biofuels. Thus, it is desirable to use more specific locally available data. The objective of this study is to characterise and quantify the contribution of biomass combustion sources to atmospheric trace gases and aerosol concentrations more representative of the national reality. Laboratory (residential wood combustion) and field (agriculture/garden waste burning and experimental wildland fires) sampling experiments were carried out. In the laboratory, after the selection of the most representative wood species and combustion equipment in Portugal, a sampling program to determine gaseous and particulate matter emission rates was set up, including organic and inorganic aerosol composition. In the field, the smoke plumes from agriculture/garden waste and experimental wildland fires were sampled. The results of this study show that the combustion equipment and biofuel type used have an important role in the emission levels and composition. Significant differences between the use of traditional combustion equipment versus modern equipments were also observed. These differences are due to higher combustion efficiency of modern equipment, reflecting the smallest amount of particulate matter, organic carbon and carbon monoxide released. With regard to experimental wildland fires in shrub dominated areas, it was observed that the largest organic fraction in the samples studied was mainly composed by vegetation pyrolysis products. The major organic components in the smoke samples were pyrolysates of vegetation cuticles, mainly comprising steradienes and sterol derivatives, carbohydrates from the breakdown of cellulose, aliphatic lipids from vegetation waxes and methoxyphenols from the lignin thermal degradation. Despite being a banned practice in our country, agriculture/garden waste burning is actually quite common. To assess the particulate matter composition, the smoke from three different agriculture/garden residues have been sampled into 3 different size fractions (PM2.5, PM2.5-10 and PM>10). Despite distribution patterns of organic compounds in particulate matter varied among residues, the amounts of phenolics (polyphenol and guaiacyl derivatives) and organic acids were always predominant over other organic compounds in the organosoluble fraction of smoke. Among biomarkers, levoglucosan, β-sitosterol and phytol were detected in appreciable amounts in the smoke of all agriculture/garden residues. In addition, inositol may be considered as an eventual tracer for the smoke from potato haulm burning. It was shown that the prevailing ambient conditions (such as high humidity in the atmosphere) likely contributed to atmospheric processes (e.g. coagulation and hygroscopic growth), which influenced the particle size characteristics of the smoke tracers, shifting their distribution to larger diameters. An assessment of household biomass consumption was also made through a national scale survey. The information obtained with the survey combined with the databases on emission factors from the laboratory and field tests allowed us to estimate the pollutant amounts emitted in each Portuguese district. In addition to a likely contribution to the improvement of emission inventories, emission factors obtained for tracer compounds in this study can be applied in receptor models to assess the contribution of biomass burning to the levels of atmospheric aerosols and their constituents obtained in monitoring campaigns in Mediterranean Europe.

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Urban soil quality may be severely affected by hydrophobic organic contaminants (HOCs), impairing environmental quality and human health. A comprehensive study was conducted in two contrasting Portuguese urban areas (Lisbon and Viseu) in order to assess the levels and potential risks of these contaminants, to identify sources and study their behaviour in soils. The concentrations of HOCs were related to the size of the city, with much higher contamination levels observed in Lisbon urban area. Source apportionment was performed by studying the HOCs profiles, their relationship with potentially toxic elements and general characteristics of soil using multivariate statistical methods. Lisbon seems to be affected by nearby sources (traffic, industry and incineration processes) whereas in Viseu the atmospheric transport may be playing an important role. In a first tier of risk assessment (RA) it was possible to identify polycyclic aromatic hydrocarbons (PAHs) in Lisbon soils as a potential hazard. The levels of PAHs in street dusts were further studied and allowed to clarify that traffic, tire and pavement debris can be an important source of PAHs to urban soils. Street dusts were also identified as being a potential concern regarding human and environmental health, especially if reaching the nearby aquatic bodies. Geostatistical tools were also used and their usefulness in a RA analysis and urban planning was discussed. In order to obtain a more realistic assessment of risks of HOCs to environment and human health it is important to evaluate their available fraction, which is also the most accessible for organisms. Therefore, a review of the processes involved on the availability of PAHs was performed and the outputs produced by the different chemical methods were evaluated. The suitability of chemical methods to predict bioavailability of PAHs in dissimilar naturally contaminated soils has not been demonstrated, being especially difficult for high molecular weight compounds. No clear relationship between chemical and biological availability was found in this work. Yet, in spite of the very high total concentrations found in some Lisbon soils, both the water soluble fraction and the body residues resulting from bioaccumulation assays were generally very low, which may be due to aging phenomena. It was observed that the percentage of soluble fraction of PAHs in soils was found to be different among compounds and mostly regulated by soil properties. Regarding bioaccumulation assays, although no significant relationship was found between soil properties and bioavailability, it was verified that biota-to-soil bioaccumulation factors were sample dependent rather than compound dependent. In conclusion, once the compounds of potential concern are targeted, then performing a chemical screening as a first tier can be a simple and effective approach to start a RA. However, reliable data is still required to improve the existing models for risk characterization.