1000 resultados para Reconocimiento material
Resumo:
Sustainable resource use is one of the most important environmental issues of our times. It is closely related to discussions on the 'peaking' of various natural resources serving as energy sources, agricultural nutrients, or metals indispensable in high-technology applications. Although the peaking theory remains controversial, it is commonly recognized that a more sustainable use of resources would alleviate negative environmental impacts related to resource use. In this thesis, sustainable resource use is analysed from a practical standpoint, through several different case studies. Four of these case studies relate to resource metabolism in the Canton of Geneva in Switzerland: the aim was to model the evolution of chosen resource stocks and flows in the coming decades. The studied resources were copper (a bulk metal), phosphorus (a vital agricultural nutrient), and wood (a renewable resource). In addition, the case of lithium (a critical metal) was analysed briefly in a qualitative manner and in an electric mobility perspective. In addition to the Geneva case studies, this thesis includes a case study on the sustainability of space life support systems. Space life support systems are systems whose aim is to provide the crew of a spacecraft with the necessary metabolic consumables over the course of a mission. Sustainability was again analysed from a resource use perspective. In this case study, the functioning of two different types of life support systems, ARES and BIORAT, were evaluated and compared; these systems represent, respectively, physico-chemical and biological life support systems. Space life support systems could in fact be used as a kind of 'laboratory of sustainability' given that they represent closed and relatively simple systems compared to complex and open terrestrial systems such as the Canton of Geneva. The chosen analysis method used in the Geneva case studies was dynamic material flow analysis: dynamic material flow models were constructed for the resources copper, phosphorus, and wood. Besides a baseline scenario, various alternative scenarios (notably involving increased recycling) were also examined. In the case of space life support systems, the methodology of material flow analysis was also employed, but as the data available on the dynamic behaviour of the systems was insufficient, only static simulations could be performed. The results of the case studies in the Canton of Geneva show the following: were resource use to follow population growth, resource consumption would be multiplied by nearly 1.2 by 2030 and by 1.5 by 2080. A complete transition to electric mobility would be expected to only slightly (+5%) increase the copper consumption per capita while the lithium demand in cars would increase 350 fold. For example, phosphorus imports could be decreased by recycling sewage sludge or human urine; however, the health and environmental impacts of these options have yet to be studied. Increasing the wood production in the Canton would not significantly decrease the dependence on wood imports as the Canton's production represents only 5% of total consumption. In the comparison of space life support systems ARES and BIORAT, BIORAT outperforms ARES in resource use but not in energy use. However, as the systems are dimensioned very differently, it remains questionable whether they can be compared outright. In conclusion, the use of dynamic material flow analysis can provide useful information for policy makers and strategic decision-making; however, uncertainty in reference data greatly influences the precision of the results. Space life support systems constitute an extreme case of resource-using systems; nevertheless, it is not clear how their example could be of immediate use to terrestrial systems.
Resumo:
The main goal of this paper is to obtain a granular material formulated with Municipal Solid Waste Incinerarion (MSWI) bottom ash (BA) and air pollution control (APC) ash to be used as secondary building material. Previously, an optimum concrete mixture using both MSWI residues as aggregates was formulated. A compromise between the environmental behaviour and the economy of the process was considered. Unconfined compressive strength and abrasion resistance values were measured in order to evaluate the mechanical properties. From these results, the granular mixture was not suited for certain applications owing to the high BA/APC content and low cement percentages used to reduce the costs of the final product. Nevertheless, the leaching test performed showed that the concentrations of all heavy metals were below the limits established by the current Catalan legislation for their reutilization. Therefore, the material studied might be mainly used in embankments, where high mechanical properties are not needed and environmental safety is assured.
Resumo:
El trabajo muestra un estudio comparativo de las soluciones que plantean diferentes soluciones comerciales y/o libres para la adecuación o no a su integración en un entorno como es el campus virtual de la UOC. Para esto se ha elaborado una lista de indicadores clave y más adelante se ha hecho una valoración de la integración en el entorno UOC, relacionando los indicadores anteriores con los requerimientos de la UOC. Investigando previamente cuales son estos. Por último se ha comprobado y corroborado la posible integración de la solución elegida al campus virtual, con el desarrollo de una pequeña aplicación web.
Resumo:
Mixture materials, mix design, and pavement construction are not isolated steps in the concrete paving process. Each affects the other in ways that determine overall pavement quality and long-term performance. However, equipment and procedures commonly used to test concrete materials and concrete pavements have not changed in decades, leaving gaps in our ability to understand and control the factors that determine concrete durability. The concrete paving community needs tests that will adequately characterize the materials, predict interactions, and monitor the properties of the concrete. The overall objectives of this study are (1) to evaluate conventional and new methods for testing concrete and concrete materials to prevent material and construction problems that could lead to premature concrete pavement distress and (2) to examine and refine a suite of tests that can accurately evaluate concrete pavement properties. The project included three phases. In Phase I, the research team contacted each of 16 participating states to gather information about concrete and concrete material tests. A preliminary suite of tests to ensure long-term pavement performance was developed. The tests were selected to provide useful and easy-to-interpret results that can be performed reasonably and routinely in terms of time, expertise, training, and cost. The tests examine concrete pavement properties in five focal areas critical to the long life and durability of concrete pavements: (1) workability, (2) strength development, (3) air system, (4) permeability, and (5) shrinkage. The tests were relevant at three stages in the concrete paving process: mix design, preconstruction verification, and construction quality control. In Phase II, the research team conducted field testing in each participating state to evaluate the preliminary suite of tests and demonstrate the testing technologies and procedures using local materials. A Mobile Concrete Research Lab was designed and equipped to facilitate the demonstrations. This report documents the results of the 16 state projects. Phase III refined and finalized lab and field tests based on state project test data. The results of the overall project are detailed herein. The final suite of tests is detailed in the accompanying testing guide.
Resumo:
This letter has been prepared as a consultation to determine some potential health concerns raised by a resident of Spencer from exposure to wire shredder fluff material emitted by Shine Brothers metal salvaging facility in Spencer, Iowa on July 10, 2011 and, a concern regarding the health impacts from the level of noise measured by a resident near the metal salvaging facility.
Resumo:
Síntesi dels primers resultats del Projecte Ager Tarraconensis i de les aportacions al simposi, de les quals s’extreuen reflexions i coneixements nous sobre el tema de l’estudi entorn del conjunt de l’espai de la ciutat romana, del paisatge, tractat com un sistema. Les aportacions se centren en la varietat de les primeres estratègies de control romà del territori, de les tipologies i evolució dels establiments, dels aspectes econòmics i de la dinàmica del poblament. Tot plegat fa referència molt especialment al territori de Tarraco, per bé que es fan nombroses comparacions amb altres territoris de l’àrea catalana i saguntina i també d’altres províncies romanes. Tarraco es va perfilant com una ciutat amb un territorium molt productiu, no sols en agricultura, sinó també en indústries, producció tèxtil, explotacions de recursos minerals com les pedreres i el ferro, i amb un comerç molt actiu que la devia convertir en un port important de la Mediterrània occidental romana. La jerarquia dels hàbitats rurals també s’està demostrant més complexa gràcies al coneixement de noves aglomeracions. L’evolució posterior al període romà també ha entrat en discussió, especialment pel que fa a l’època islàmica, sobre la qual es discuteix si el camp va quedar poblat o despoblat, tema que resol en sentit positiu el diagrama pol·línic realitzat dins del marc del projecte.
Resumo:
L'educació i la reeducació de la veu tenen un llarg recorregut professional. A partir dels coneixements i de les tècniques provinents del món del cant i de la medicina, s'ha anat constituint un corpus de practiques professionals d'efectivitat contrastada en l'exercici quotidià. Componen una part d'aquest corpus les vocalitzacions que el pacient practica en les sessions terapèutiques. Aquest article pretén explicar les bases fisiològiques per escollir quin material fonètic s'empra en aquests exercicis.
Resumo:
Aquest petit treball pretén esdevenir una guia bàsica per aquells arqueòlegs que desconeixen l’aspecte conservatiu dels materials arqueològics. Així, en primer lloc analitzarem, a grans trets, la composició físicoquímica dels diferents objectes que podem trobar en una excavació i quins són els agents que més els malmeten. Després tractarem d’introduir alguns consells pràctics pel treball de camp.
Resumo:
This research report illustrates and examines new operation models for decreasing fixed costs and transforming them into variable costs in the field of paper industry. The report illustrates two cases - a new operation model for material logistics in maintenance and an examination of forklift truck fleet outsourcing solutions. Conventional material logistics in maintenance operation is illustrated and some problems related to conventional operation are identified. A new operation model that solves some of these problems is presented including descriptions of procurement and service contracts and sources of added value. Forklift truck fleet outsourcing solutions are examined by illustrating the responsibilities of a host company and a service provider both before and after outsourcing. The customer buys outsourcingservices in order to improve its investment productivity. The mechanism of how these services affect the customer company's investment productivity is illustrated.
Resumo:
The domestic hot water cylinder incorporates encapsulated pcm placed in 57 vertical pipes. The use of PCM increases the thermal energy storage capacity of the cylinder and allows the use of low cost electricity during low peak periods. After experimental validation the numerical model developed in the project will be used to optimize the distribution of the pcm inside the water tank.
Resumo:
Hem dissenyat un sistema de presentacions interactives que sincronitza diferents continguts multimèdia utilitzant el llenguatge SMIL. Aquests continguts són: un vídeo on un professor presenta una matèria, un seguit de transparències que il·lustren la seva presentació i una taula de continguts que en mostra un esquema i permet navegar-hi. També hem creat una aplicació que facilitarà l'edició d'aquestes presentacions.
Resumo:
El proyecto está basado en un sistema que denominaremos Material Market a lo largo de todo el trabajo. La idea que subyace detrás de este Market es un sistema que gestiona la compra-venta de materiales por parte de los usuarios del sistema.
Resumo:
A ocorrência do distúrbio fisiológico conhecido como "Mancha Fisiológica do Mamão" (MFM) tem comprometido a qualidade do mamão (Carica papaya L.) produzido no Brasil. A obtenção de material genético tolerante à MFM faz parte das estratégias de ação de médio a longo prazo para minimizar os prejuízos decorrentes da ocorrência desse distúrbio. No presente trabalho, buscou-se avaliar a tolerância de vinte e dois híbridos de mamão à ocorrência da MFM, na região norte do Estado do Rio de Janeiro. Os frutos foram colhidos de um ensaio de competição instalado na Estação Experimental da PESAGRO-Rio, no município de Macaé-RJ. O ensaio consistiu de quatro repetições, num delineamento em blocos ao acaso, sendo que cada parcela foi constituída de oito plantas. Os dados foram submetidos a uma análise de variância e teste de média. Efetuou-se, inicialmente, uma análise conjunta, envolvendo os dois estádios de maturação avaliados - verde-maduro e ¾ maduro; considerando a significância da interação Estádio x Genótipo, procedeu-se a uma análise específica, por estádio de desenvolvimento do fruto. Em função da análise de variância, também, foi calculado o coeficiente de determinação genotípica (H²) para o caráter em estudo, o qual demonstrou que a avaliação do nível de severidade da MFM, no estádio ¾ maduro, caracteriza melhor as diferenças genotípicas. Com base nesses resultados, inferimos que há uma expressiva variabilidade genética, para o caráter MFM, dentre os genótipos avaliados. Isto sugere um bom potencial em se obter, através do melhoramento genético, material vegetal (híbridos e variedades) com maior tolerância à MFM. O melhoramento genético associado ao manejo do ambiente poderá permitir o cultivo do mamoeiro sem as limitações advindas da ocorrência da MFM.