566 resultados para Inventories


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The main aim of this study was to evaluate the impact of the urban pollution plume from the city of Manaus by emissions from mobile and stationary sources in the atmospheric pollutants concentrations of the Amazon region, by using The Weather Research and Forecasting with Chemistry (WRF-Chem) model. The air pollutants analyzed were CO, NOx, SO2, O3, PM2.5, PM10 and VOCs. The model simulations have been configured with a grid spacing of 3 km, with 190 x and 136 y grid points in horizontal spacing, centered in the city of Manaus during the period of 17 and 18 of March 2014. The anthropogenic emissions inventories have gathered from mobile sources that were estimated the emissions of light and heavy-duty vehicles classes. In addition, the stationary sources have considered the thermal power plants by the type of energy sources used in the region as well as the emissions from the refinery located in Manaus. Various scenarios have been defined with numerical experiments that considered only emissions by biogenic, mobile and stationary sources, and replacement fuel from thermal power plant, along with a future scenario consisting with twice as much anthropogenic emissions. A qualitative assessment of simulation with base scenario has also been carried out, which represents the conditions of the region in its current state, where several statistical methods were used in order to compare the results of air pollutants and meteorological fields with observed ground-based data located in various points in the study grid. The qualitative analysis showed that the model represents satisfactorily the variables analyzed from the point of view of the adopted parameters. Regarding the simulations, defined from the base scenarios, the numerical experiments indicate relevant results such as: it was found that the stationary sources scenario, where the thermal power plants are predominant, resulted in the highest concentrations, for all air pollutants evaluated, except for carbon monoxide when compared to the vehicle emissions scenario; The replacement of the energy matrix of current thermal power plants for natural gas have showed significant reductions in pollutants analyzed, for instance, 63% reductions of NOx in the contribution of average concentration in the study grid; A significant increase in the concentrations of chemical species was observed in a futuristic scenario, reaching up to a 81% increase in peak concentrations of SO2 in the study area. The spatial distributions of the scenarios have showed that the air pollution plume from Manaus is predominantly west and southwest, where it can reach hundreds of kilometers to areas dominated by original soil covering.

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I investigate the effects of information frictions in price setting decisions. I show that firms' output prices and wages are less sensitive to aggregate economic conditions when firms and workers cannot perfectly understand (or know) the aggregate state of the economy. Prices and wages respond with a lag to aggregate innovations because agents learn slowly about those changes, and this delayed adjustment in prices makes output and unemployment more sensitive to aggregate shocks. In the first chapter of this dissertation, I show that workers' noisy information about the state of the economy help us to explain why real wages are sluggish. In the context of a search and matching model, wages do not immediately respond to a positive aggregate shock because workers do not (yet) have enough information to demand higher wages. This increases firms' incentives to post more vacancies, and it makes unemployment volatile and sensitive to aggregate shocks. This mechanism is robust to two major criticisms of existing theories of sluggish wages and volatile unemployment: the flexibility of wages for new hires and the cyclicality of the opportunity cost of employment. Calibrated to U.S. data, the model explains 60% of the overall unemployment volatility. Consistent with empirical evidence, the response of unemployment to TFP shocks predicted by my model is large, hump-shaped, and peaks one year after the TFP shock, while the response of the aggregate wage is weak and delayed, peaking after two years. In the second chapter of this dissertation, I study the role of information frictions and inventories in firms' price setting decisions in the context of a monetary model. In this model, intermediate goods firms accumulate output inventories, observe aggregate variables with one period lag, and observe their nominal input prices and demand at all times. Firms face idiosyncratic shocks and cannot perfectly infer the state of nature. After a contractionary nominal shock, nominal input prices go down, and firms accumulate inventories because they perceive some positive probability that the nominal price decline is due to a good productivity shock. This prevents firms' prices from decreasing and makes current profits, households' income, and aggregate demand go down. According to my model simulations, a 1% decrease in the money growth rate causes output to decline 0.17% in the first quarter and 0.38% in the second followed by a slow recovery to the steady state. Contractionary nominal shocks also have significant effects on total investment, which remains 1% below the steady state for the first 6 quarters.

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Methods to measure enteric methane (CH4) emissions from individual ruminants in their production environment are required to validate emission inventories and verify mitigation claims. Estimates of daily methane production (DMP) based on consolidated short-term emission measurements are developing, but method verification is required. Two cattle experiments were undertaken to test the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate did not differ from DMP measured in respiration chambers (RC). Short-term emission rates were obtained from a GreenFeed Emissions Monitoring (GEM) unit, which measured emission rate while cattle consumed a dispensed supplement. In experiment 1 (Expt. 1), four non-lactating cattle (LW=518 kg) were adapted for 18 days then measured for six consecutive periods. Each period consisted of 2 days of ad libitum intake and GEM emission measurement followed by 1 day in the RC. A prototype GEM unit releasing water as an attractant (GEM water) was also evaluated in Expt. 1. Experiment 2 (Expt. 2) was a larger study based on similar design with 10 cattle (LW=365 kg), adapted for 21 days and GEM measurement was extended to 3 days in each of the six periods. In Expt. 1, there was no difference in DMP estimated by the GEM unit relative to the RC (209.7 v. 215.1 g CH4/day) and no difference between these methods in methane yield (MY, 22.7 v. 23.7 g CH4/kg of dry matter intake, DMI). In Expt. 2, the correlation between GEM and RC measures of DMP and MY were assessed using 95% confidence intervals, with no difference in DMP or MY between methods and high correlations between GEM and RC measures for DMP (r=0.85; 215 v. 198 g CH4/day SEM=3.0) and for MY (r=0.60; 23.8 v. 22.1 g CH4/kg DMI SEM=0.42). When data from both experiments was combined neither DMP nor MY differed between GEM- and RC-based measures (P>0.05). GEM water-based estimates of DMP and MY were lower than RC and GEM (P<0.05). Cattle accessed the GEM water unit with similar frequency to the GEM unit (2.8 v. 3.5 times/day, respectively) but eructation frequency was reduced from 1.31 times/min (GEM) to once every 2.6 min (GEM water). These studies confirm the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate using GEM does not differ from measures of DMP obtained from RCs. Further, combining many short-term measures of methane production rate during supplement consumption provides an estimate of DMP, which can be usefully applied in estimating MY.

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Svalbard is a heavily glacier-covered archipelago in the Arctic. Dickson Land (DL), in the central part of the largest island, Spitsbergen, is relatively arid, and as a result, glaciers there are relatively small and restricted mostly to valleys and cirques. This study presents a comprehensive analysis of glacier changes in DL based on inventories compiled from topographic maps and digital elevation models for the Little Ice Age maximum (LIA), the 1960s, 1990 and 2009/11. Total glacier area decreased by ~38 % since the LIA maximum, and front retreat has increased over the study period. Recently, most of the local glaciers have been consistently thinning in all elevation bands, in contrast to larger Svalbard ice masses which remain closer to balance. The mean 1990–2009/11 geodetic mass balance of glaciers in DL is among the most negative from the Svalbard regional means known from the literature.

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The subpolar North Atlantic (SPNA) is important in the global carbon cycle because of the deep water ventilation processes that lead to both high uptake of atmospheric CO2 and large inventories of anthropogenic CO2 (C-ant). Thus, it is crucial to understand its response to increasing anthropogenic pressures. In this work, the budgets of dissolved inorganic carbon (DIC), C-ant and natural DIC (DICnat) in the eastern SPNA in the 2000s, are jointly analyzed using in situ data. The DICnat budget is found to be in steady state, confirming a long-standing hypothesis from in situ data for the first time. The biological activity is driving the uptake of natural CO2 from the atmosphere. The C-ant increase in the ocean is solely responsible of the DIC storage rate which is explained by advection of C-ant from the subtropics (65%) and C-ant air-sea flux (35%). These results demonstrate that the C-ant is accumulating in the SPNA without affecting the natural carbon cycle.

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The faunal inventory of the macroinvertebrate community is important to the environmental assessment, since this biota is sensitive to human disturbance. The reservoir of Rio Verde, located on the first plateau of Paraná, is inserted into an agricultural region with several forest fragments Araucaria. The aim of this study was to evaluate the environmental integrity of the reservoir through ecological indexes of macroinvertebrate community benthic and associated with macrophytes. Five sampling points were defined in the study area, which comprise distinct microhabitats in the basin. There were four sampling campaigns, each by weather station: Spring (2014); Summer (2015); Autumn (2015) and Winter (2015). In each sample were measured abiotic various parameters in the field and be collected water samples for nutrient analysis in the laboratory. The macroinvertebrates were collected in triplicate at adapted Macan method using mesh sieve 1 mm and CPUE (catch per unit effort) for 20 minutes. In order to pellet sample was used a dredger model Petersen 2L. Still in the field, by season, samples were collected from macrophytes Myriophyllum aquaticum (Vell) Verdc. and Potamogeton montevidensis A. Benn. in triplicates in the fluvial region of the reservoir, to analyze the associated fractal dimension and macrofauna. For this we used a PVC sampler specific volume 0.025 m3. the following ecological descriptors were calculated in each case: abundance, wealth tax, wealth Margalef, Shannon-Wiener diversity, evenness evenness through the Past software. The index Biological Monitoring Working Party (BMWP) for monitoring sampling points was also calculated. Regarding the statistical analysis, we used the analysis of PERMANOVA to compare points and seasons and canonical correspondence analysis (CCoA) for variables. Regarding M. aquaticum and P. montevidensis it was not verified difference to the average associated macroinvertebrates. However there was a difference for abundance of organisms in the fractal dimension and biomass of specimens. M. aquaticum is more complex and took more macrofauna in relation to P. montevidensis. Regarding the monitoring of the reservoir, it showed up mesotrophic with moderate nutrient concentrations and within the regulatory limits. Benthic macrofauna showed statistical differences in relation to the reservoir region, sample point and temporal variation. The BMWP index showed that the river region has the highest biotic integrity (in all samples above 70 points), and the ecological descriptors of wealth and Margalef diversity of Shannon- Wiener higher. In point 4 (dam downstream) were recorded evidence of possible impacts due to lower wealth and BMWP index which resulted in a questionable quality water. New approaches are needed to focus on the aquatic community in the best understanding of this ecosystem and also with a view to environmental preservation of the Green River Basin.

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Mass Customization (MC) is not a mature business strategy and hence it is not clear that a single or small group of operational models are dominating. Companies tend to approach MC from either a mass production or a customization origin and this in itself gives reason to believe that several operational models will be observable. This paper reviews actual and theoretical fulfilment systems that enterprises could apply when offering a pre-engineered catalogue of customizable products and options. Issues considered are: How product flows are structured in relation to processes, inventories and decoupling point(s); - Characteristics of the OF process that inhibit or facilitate fulfilment; - The logic of how products are allocated to customers; - Customer factors that influence OF process design and operation. Diversity in the order fulfilment structures is expected and is found in the literature. The review has identified four structural forms that have been used in a Catalogue MC context: - fulfilment from stock; - fulfilment from a single fixed decoupling point; - fulfilment from one of several fixed decoupling points; - fulfilment from several locations, with floating decoupling points. From the review it is apparent that producers are being imaginative in coping with the demands of high variety, high volume, customization and short lead times. These demands have encouraged the relationship between product, process and customer to be re-examined. Not only has this strengthened interest in commonality and postponement, but, as is reported in the paper, has led to the re-engineering of the order fulfilment process to create models with multiple fixed decoupling points and the floating decoupling point system

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Rezension von: Gerard Kahn: Janusz Korczak und die jüdische Erziehung. Janusz Korczaks Pädagogik auf dem Hintergrund seiner jüdischen Herkunft. Deutscher Studien Verlag 2. Aufl. 1993, 164 S.

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Sammelrezension von: 1. BIOS-Zeitschrift für Biographieforschung und Oral History. Hrsg. von Werner Fuchs-Heinritz, Albrecht Lehmann und Lutz Niethammer. Erscheint zweimal jährlich im Umfang von ca. 160 Seiten. Leverkusen: Leske+Budrich. Einzelheft. 2. History and Memory. Studies in Representation of the Past. Ed. at the Aranne School of History, Tel Aviv University. Eds. Saul Friedländer/Dan Diner. Erscheint zweimal jährlich. Frankfurt a. M.: Athenäum. Einzelheft

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A fauna de mamíferos do estado de São Paulo consta de 231 táxons, sendo este número uma estimativa da real diversidade presente na região, dado a falta de amostragem em grandes extensões do estado, e também de revisões taxonômicas para determinados grupos. Ainda assim, nosso conhecimento aumentou em 20% desde a última estimativa em 1998, principalmente em relação aos quirópteros e roedores. Estes dados são provenientes de inventários faunísticos, e também do estudo de espécimes depositados em coleções científicas oriundos de revisões taxonômicas. Também temos um maior volume de dados a respeito da distribuição dos mamíferos em relação às diferentes paisagens presentes no estado, o que nos permite dividir a mastofauna em três componentes distintos: o mais importante desses é o das espécies generalistas, que ocorrem em todas as principais paisagens do estado; o segundo grupo concentra espécies das formações abertas, e o terceiro grupo inclui as espécies essencialmente florestais. Além disso, o número de estudos que tem se preocupado com o efeito da fragmentação de hábitats sobre as comunidades de mamíferos, bem como a respeito da permeabilidade das espécies em áreas alteradas, também aumentaram. Dados a respeito da ocorrência, abundância e vulnerabilidade das espécies foram essenciais para traçar estratégias em relação à escolha de áreas e à indicação de ações prioritárias para a conservação dos mamíferos no estado, assim como classificar as espécies nas diferentes categorias de ameaças propostas, culminando na Lista das Espécies Ameaçadas do Estado de São Paulo. Entretanto, ainda existem inúmeras lacunas de conhecimento, que vão desde o número limitado de amostras zoológicas, até a falta de informações acerca da ecologia e história natural de várias espécies. É imprescindível que aumentemos as amostras de mamíferos em coleções zoológicas, principalmente em áreas de Floresta Ombrófila Densa, nos fragmentos de Cerrado, bem como em áreas do centro e oeste do Estado, que permanecem ainda pouco estudadas, com o objetivo de produzir um maior número de revisões taxonômicas em diversos grupos de mamíferos, e de estudos com abordagens filogeográficas e de genética de populações, para diagnosticarmos de forma efetiva a riqueza de mamíferos no estado, bem como os mecanismos evolutivos responsáveis por esta diversificação. Aliados a esses estudos serão necessárias abordagens ecológicas para gerarmos conhecimento, que em conjunto, nos permitirá avaliarmos o estado de conservação dos mamíferos de São Paulo e tomarmos decisões sobre as melhores estratégias para manejarmos e preservarmos estas espécies.

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En el presente trabajo se pretende evidenciar el proceso de desarrollo de una pieza de arcilla cocida de gran formato en las instalaciones de la planta de Itagüí de la Ladrillera San Cristóbal S.A. y posteriormente analizar, a través de la metodología del Análisis de ciclo de vida, los resultados de la medición de los impactos ambientales al construir un metro cuadrado de muro no estructural empleando dicha pieza -- Y compararlos, finalmente, con los efectos provocados por un ladrillo convencional de medidas nominales (10 cm x 20 cm x 40 cm), el cual se usa con mayor frecuencia en la mampostería no estructural en Antioquia -- El proceso de fabricación de una pieza de cerámica roja comprende las siguientes etapas: extracción minera, preparación de materias primas, moldeo, secado y cocción -- Para el desarrollo de la pieza cerámica se tomaron materias primas de varios de los títulos mineros de la empresa, haciendo siempre énfasis en aquellos que estuvieran más próximos al centro de producción -- Con ellas, se formuló una pasta cerámica que presentó el mejor comportamiento en cada una de las etapas críticas del proceso y condujo a lograr las mejores propiedades cerámicas y mecánicas de la pieza desarrollada -- Inicialmente, la pasta cerámica se acondicionó en los molinos del laboratorio, consecutivamente fue llevada a producción industrial una cantidad de 30 toneladas que procedió con la realización de los lotes en diferentes oportunidades -- La conformación de la pieza se efectuó con un molde “boquilla” que fue planteado con el equipo de diseño de la empresa y el personal de mantenimiento que la fabricó -- Posteriormente, se proyectaron ensayos de secado a diferentes piezas, para lograr simular los valores obtenidos de la pasta cerámica desarrollada a escala de laboratorio -- De esta manera, se pudo secar la pieza en un periodo inferior a las 24 horas, el tiempo aproximado que requiere la línea de producción sin ser afectada en el proceso continuo que funciona los siete días de la semana -- En caso de tener que someter la pieza a secados más extensos, el proyecto se vería perjudicado en su viabilidad -- En el horno se emplearon dos curvas de cocción de las piezas secas, debido a que inicialmente la pasta cerámica desarrollada en el laboratorio fue sometida a temperaturas entre 900 y 1000 grados centígrados -- En este rango se lograron valores de absorción de agua inferiores al 16% y una buena estabilidad del material a la quema, lo cual condujo a una aceptación de los obtenidos en cuanto a resistencia a la compresión de las piezas se refiere -- El Análisis de ciclo de vida realizado para comparar los impactos ambientales de un ladrillo tradicional versus una pieza de gran formato utilizando las metodologías de análisis de los inventarios de ciclo de vida Ecoindicador99, CML2001 Y ReciPe reforzó la hipótesis de que la principal reducción de los impactos de un tipo de ladrillo a otro se encuentra asociada a la etapa de manufactura y uso del producto -- En esa medida, se evidenció que los consumos de materiales y energía de una pieza de gran formato son menores que los de un ladrillo tradicional a lo largo de todo el ciclo de vida

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El presente trabajo de titulación consiste en evaluar los riesgos en el manejo de inventarios de las distribuidoras de productos de consumo masivo de la ciudad de Cuenca, mediante una investigación de mercado, con el objetivo de elaborar un estudio actual sobre los riesgos más frecuentes a los que se ven expuestas en su manejo de inventarios, si los identifican y los evalúan, y, cuáles son los controles que utilizan para prevenirlos; investigación ejecutada mediante la aplicación de encuestas realizadas a un grupo de distribuidoras, representativas de la población total; resultados que permiten emitir soluciones al caso práctico Distribuidora DIPROSUM. El caso práctico, consiste en la evaluación de los riesgos en el manejo de inventarios de la Distribuidora DIPROSUM correspondiente al período del 01 de Enero al 31 de Diciembre de 2014, aplicando el modelo COSO I del Comité de Organizaciones Patrocinadoras de la Comisión de Treadway, compuesto de cinco componentes que son: Ambiente de Control, Evaluación de Riesgos, Actividades de Control, Información y Comunicación y, Monitoreo, mediante la metodología de cuestionarios para la obtención de los aspectos negativos o débiles considerados como riesgos que afectan al correcto manejo del inventario, calificando y evaluando los riesgos identificados, en la que los resultados se ven reflejados en el informe final con sus respectivas conclusiones y recomendaciones.

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Rapport de stage présenté à la Faculté des études supérieures en vue de l’obtention du grade de maîtrise en génie biomédical Option Clinique