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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Ciclagem de macronutrientes em sistemas integrados de produção agropecuária no Centro-Sul do Paraná / Nutrient cycling in integrated crop-livestock systems in the Paraná Southern-Central

Carpinelli, Sandoval 17 March 2017 (has links)
Submitted by Eunice Novais (enovais@uepg.br) on 2018-03-15T13:24:23Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Sandoval Carpinelli.pdf: 1473498 bytes, checksum: 55c2940ffe8b169a79a9863fc0aa64c0 (MD5) / Made available in DSpace on 2018-03-15T13:24:23Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Sandoval Carpinelli.pdf: 1473498 bytes, checksum: 55c2940ffe8b169a79a9863fc0aa64c0 (MD5) Previous issue date: 2017-03-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os sistemas integrados de produção agropecuária (SIPA) possibilitam sinergismo entre as atividades agrícolas, pecuária e/ou florestal, realizadas na mesma área de cultivo, buscando maximizar os fatores de produção. Modificações no microclima, em SIPA, podem afetar a deposição e a decomposição do resíduo, bem como a liberação e a ciclagem dos nutrientes no sistema de produção. Os objetivos deste trabalho foram: (i) quantificar o aporte dos resíduo e de macronutrientes em SIPA, sob Cambissolo Háplico de textura média, nos Campos Gerais do Paraná; (ii) estimar a taxa de decomposição do resíduo e a liberação de macronutrientes da cultura de soja e da biomassa de forragem anual de inverno (consórcio de aveia preta e azevém anual), em SIPA. O delineamento experimental empregado foi o de blocos completos casualizados com três repetições. Os tratamentos consistiram de combinações de presença de componente arbóreo (eucalipto + grevílea) e doses (90 e 180 kg ha-1) de nitrogênio mineral (ureia – 450 g kg-1 de N) aplicado na pastagem anual de inverno. De modo a melhor representar o ambiente arborizado, foi feita a subdivisão da unidade experimental em cinco distâncias. O experimento foi implantado em 2006; no entanto, as avaliações inerentes a este trabalho foram realizadas no período compreendido entre os meses de dezembro/2014 a outubro/2015. Nesse período foram inseridos aleatoriamente litter bags de resíduo de forragem anual de inverno e de soja, nos tratamentos com ausência e presença do componente arbóreo, respectivamente. As amostragens do material contido nos litter bags foram realizadas aos 7, 15, 30, 60, 90 e 120 dias após a semeadura das culturas (tanto verão quanto de inverno). Foram realizadas as seguintes avaliações: quantidade e qualidade do resíduo vegetais, taxa de decomposição do resíduo vegetal remanescente e de liberação dos macronutrientes (nitrogênio - N, fósforo - P, potássio - K, cálcio - Ca, magnésio - Mg e enxofre - S) dos resíduos, tanto da fase de lavoura como da fase pastagem, ao longo do tempo. A interação entre os fatores avaliados afetou a liberação do S do resíduo do pasto e o K do resíduo de soja. O sistema arborizado, bem como a menor dose de nitrogênio, ocasionou menor massa de resíduo (tanto da pastagem como da lavoura) quando comparado aos demais tratamentos. A quantidade de resíduo da pastagem foi afetada pela distância das árvores. Maiores concentrações dos macronutrientes (K, Ca e Mg) no resíduo da pastagem, ao final do período de pastejo, foram observadas no sistema arborizado. A ausência do componente arbóreo ocasionou maiores concentração de Ca e Mg no resíduo da soja. Além da maior quantidade de massa de resíduo da soja na maior dose de N, tal resíduo apresentava maior concentração em K e S do que a menor dose. Variações na taxa de decomposições de massa seca remanescente dos resíduos da pastagem e soja também foram influenciadas pela distância em relação aos renques arbóreos. A liberação de N, P, K e Mg do resíduo pasto e de P, Mg e S do resíduo da soja não foi influenciada pelos tratamentos. A decomposição do resíduo da pastagem e seu respectivo efeito proporcionou uma maior ciclagem de nutrientes para a soja do que o oposto. / Integrated crop-livestock systems (ICLS) enable synergism between agricultural, livestock and/or forestry activities carried out in the same area, focusing maximization of production factors. Changes in ICLS microclimates can affect the deposition and decomposition of plant residues, as well as macronutrient and nutrient cycling present in the system. The aims of this study were (i) to quantify the contribution of plant residues and macronutrients in ICLS, under loamy-sand Typic Distrudept, in the Paraná Campos Gerais area; and (ii) to estimate the decomposition of the residue and the release of macronutrients from the soybean crop and the biomass of annual winter forage (consortium of black oats and annual ryegrass) in ICLS. The experimental design was a randomized complete block with three replicates. The treatments consisted of combinations of the presence of an arboreal component (eucalyptus + Grevillea) and doses (90 and 180 kg N ha-1year-1) of mineral nitrogen (as urea - 450 g kg-1 N) applied to the annual intercropped pasture. In order to better represent the forested environment, the experimental unit was subdivided into five distances. The experiment was implemented in 2006. However, the evaluations inherent to this study were carried out from December 2014 up to October 2015. During this period, litterbags of a consortium of black oat residues with ryegrass and soybean were randomly inserted in the treatments with the absence and presence of the arboreal component, respectively. Samplings of the material contained in the litterbags were carried out at 7, 15, 30, 60, 90 and 120 days after crop sowing (both in summer and winter). The following evaluations were performed: amount and quality of the plant residue, decomposition rate of the remaining plant residue and macronutrient release (nitrogen - N, phosphorus - P, potassium - K, calcium - Ca, magnesium - Mg and sulfur - S) of the residue, both in the tillage phase and in the pasture stage, over time. The forested system, as well as the lower nitrogen dose, presented lower residue mass (both in the pasture and in the crop) compared to the other treatments. Tree distances also affected the amount of grass residue. The highest mean macronutrient concentrations (K, Ca and Mg) in the pasture residue at the end of the grazing period was observed in the arboreal system. The no-tree system resulted in higher concentrations of Ca and Mg in the soybean residue when compared to the arboreal system. In addition to the greater amount of soybean residue mass at the highest N dose, this residue presented higher N, K and S concentrations compared to the lowest dose. Variations in the decomposition rate of remaining pasture and soybean residue dry mass also occurred as a function of distance from tree trunks. The evaluated factors did not affect the release of P, K and Mg from the pasture residue and P, Mg and S from the soybean residue. The interaction between the evaluated affected S release from the pasture residue and K from the soybean residue. The decomposition of the residue of pasture and its respective effect rovided a greater cycling of nutrients for soybean.
82

Avaliação de bolsas plásticas utilizadas para acondicionamento de sangue e hemocomponentes. / Evaluation of plastic bags used for packaging of blood and blood components.

FERREIRA, Leila Aparecida Alvim de Paula. 13 April 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-13T17:35:52Z No. of bitstreams: 1 LEILA APARECIDA ALVIM DE PAULA FERREIRA - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2101894 bytes, checksum: 086e0e07fb7a86bb4092c49f395ed931 (MD5) / Made available in DSpace on 2018-04-13T17:35:52Z (GMT). No. of bitstreams: 1 LEILA APARECIDA ALVIM DE PAULA FERREIRA - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2101894 bytes, checksum: 086e0e07fb7a86bb4092c49f395ed931 (MD5) Previous issue date: 2014-07-18 / Este trabalho teve como objetivo a avaliação físico-química, morfológica e estrutural das bolsas de Policloreto de Vinila (PVC) para acondicionamento de sangue e hemocomponentes. As amostras de bolsas plásticas Nacionais e do Exterior utilizadas para este estudo foram selecionadas no Sistema de Dados da ANVISA - DATAVISA entre as bolsas regularizadas junto à ANVISA. As bolsas constituídas de PVC foram caracterizadas por Espectroscopia na Região de Infravermelho com Transformada de Fourier (FTIR), Difração de Raios X (DRX), Microscopia Óptica (MO), Microscopia Eletrônica de Varredura (MEV)/ Espectroscopia por Energia Dispersa de Raios X (EDS), Microscopia de Força Atômica (MFA) e Ensaios Mecânicos (Tração). As análises foram realizadas no Laboratório de Desenvolvimento e Avaliação de Biomateriais (CERTBIO). De acordo com os resultados observados no ensaio de FTIR, pode-se afirmar que todos os componentes apresentam grupos funcionais semelhantes. No DRX foi observado que as amostras apresentaram um perfil de material com caráter semicristalino. Na MO e MEV observou-se um lado mais liso e outro mais rugoso com algumas irregularidades na superfície da amostra. Conforme o ensaio de EDS, os elementos químicos identificados, bem como a concentração dos mesmos, demonstrou que as bolsas seguem um mesmo critério de composição. Baseado nos resultados de ensaios mecânicos para ambos fabricantes, as bolsas de sangue sem anticoagulante apresentaram menor deformação em relação as bolsas de sangue com anticoagulante. Todas as bolsas apresentaram comportamento de material viscoelástico. Desta forma, pode-se concluir que todos os ensaios de caracterização utilizados neste trabalho foram relevantes para avaliação da qualidade das bolsas plásticas para acondicionamento de sangue e hemocomponentes existentes no mercado, considerando os requisitos gerais e específicos estabelecidos nas normas e legislações vigentes. / This research has the objective the physical chemical, morphological and structural evaluation of Polyvinyl Chloride (PVC) bags for blood filling and hemocomponentes. The samples from national and imported blood bags used for this research were selected through ANVISA database from blood bags regularly released by that. The PVC blood bags were characterized by Fourier transform Infrared (FTIR), X-ray Diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersed spectroscopy X-ray (EDS), Atomic Force Microscopy (AFM) and Mechanical Testing. The analyses were performed on Biomaterial development and evaluation lab (CERTBIO). On Fourier transform Infrared (FTIR) it was observed that all components show chemical similarity. On XRD was noticed that the samples have showed a semi crystalline characteristics. On OM and SEM it was noticed that the sample has a smooth side and other with sprinkles on surface. ON EDS assay it was observed conformity on chemical compounds identified as well as on their strength. It demonstrates that blood bags follow the same composition criteria. Based on mechanical tests results for both manufacturers, the blood bags without anticoagulant showed less deformation compared to blood bags with anticoagulant. All bags showed viscoelastic material behavior. Thus, we can conclude that all characterization tests used in this study were relevant to assessing the quality of the bags that are used as containers of blood and its components existing on the market, considering the general and specific requirements established in rules and regulations.
83

Manuál pro výběr tenisového vybavení pro hráče a trenéry / Guide for selection of tennis equipment for players and coaches

Čihák, Josef January 2018 (has links)
Title: Guide for selection of tennis equipment for players and coaches Objectives: The main purpose of this thesis is to create a detailed guide for selecting tennis equipment for players and coaches, which will help players choose right racquet, strings, balls, shoes and bags. At the same time, it will inform the reader about equipment for tennis coaches. In addition a questionnare will be elaborated to detect the equipment preferences of players at performance level. Methods: Content analysis of documents was used in this thesis and was completed by a questionnare. Results: Result of this thesis is a guide for selecting tennis equipment for players and a coach, which helps people choose the right racquet and strings. One will also gain better knowledge of tennis ball characteristics in connection with different surfaces and varying game styles. Also results from the questionnare will be elaborated to illustrate the preferences of players at performance level. Keywords: Tennis, guide, tennis racquets, tennis strings, tennis shoes, tennis bags, tennis balls, history of tennis, tennis accessories, equipment, coach.
84

Myten om att vara först : En studie om first-mover fördelar inom företag som levererar färdiga matkassar på internet i Sverige

Rossev Berent, Alexander, Warvsten, Leonard January 2017 (has links)
Background: A common assumption in business research is that first-movers in new markets often tends to have competitive advantages that sequent companies find difficult to compete with. Recently the formal research usability has begun to be questioned. The empirical basis there search of this area rests on, is criticized of being too homogenous. The research that’s been done have often focused on specific industries with certain types of entry barriers. Purpose: The purpose of this paper is to study if there are benefits to being a first-mover in the industry for grocery bags online. The study will use a methodological triangulation in an effort to make a methodological contribution in this research field. Theory: The theoretical framework used in the study is First-mover advantage and Later-entrant advantage. Delimitations: The quantitative part of the study will analyze 15 companies dealing with grocery bags online in Sweden. In the qualitative part of the study a delineation of the population will be made. Five companies were chosen for this part of the study. Methodology: A methodological triangulation was used to increase coherence in the study. Information about the 15 companies consisted of different types of documents such as annual reports and press releases. In the qualitative part of the study semi-structured interviews with different respondents at the different companies was done. / Bakgrund: Ett vanligt förekommande antagande inom företagsekonomin är att företag som är först in på en marknad ofta har långtgående konkurrensfördelar som efterföljande företag har svårt att konkurrera med. På senare tid har forskningens användbarhet börjat bli ifrågasatt. Det empiriska underlaget som forskningsfältet vilar på kritiseras för att vara för homogent. Forskningen är ofta gjord på industriella företag med specifika inträdesbarriärer. Syfte: Syftet med studien är att undersöka faktorerna som avgör en first-movers fördelar samt resultatet av fördelarna. Studien undersöker företag som levererar färdiga matkassar på internet i Sverige. Med hjälp av en metodologisk triangulering kommer ett bidrag att göras till forskningsfältet. Teoretiskt perspektiv: Det teoretiska ramverk som använts i undersökningen är first-mover advantage och Later-entrant advantage. Avgränsning: Undersökningen är avgränsad till att undersöka registrerade bolag i Sverige som levererar färdigplanerade matkassar på internet. Urvalet för den kvantitativa undersökningen består av 15 företag. I den kvalitativa undersökningen, består urvalet av 5 företag. Metod: Undersökningen är uppdelad i två delar där två olika metoder användes. Dels en kvantitativ undersökning och en kvalitativ undersökning. En metodtriangulering genomfördes för att öka samstämmigheten i undersökningen. Information om de 15 företagen hämtades från olika typer av dokument, som årsredovisningar och pressmeddelanden. I den kvalitativa undersökningen genomfördes semistrukturerade intervjuer med olika nyckelpersoner på företagen.
85

Rätt skatt på rätt plats? : En studie av hinder och drivkrafter för implementeringen av den svenska skatten på plastbärkassar / The right tax in the right place? : A study of barriers and drivers for the implementation of the Swedish tax on plastic carrier bags

Sjulander, Jennifer January 2021 (has links)
Skatten på engångsplastbärkassar som implementerades i Sverige år 2020 möttes med ideologiskt motstånd. Den forskning som gör gällande skatt på plastbärkassar finns främst i internationell kontext och är fokuserad på konsumenters beteenden och reaktioner. Denna studie gör gällande hur berörda verksamheter och organisationer resonerar kring skattens införande, samt dess resultat. Studien syftar också till att identifiera hinder och drivkrafter för implementeringen. För att undersöka förhållandet användes en explorativ ansats där intervjuer med en variation av berörda verksamheter utgjorde materialet för studien. Resultaten visar på att implementeringen mötts av missnöje av hälften av deltagarna på grund av skattens singulära syfte, samtidigt som den andra hälften anser att tillämpningsområdet var tillfredsställande. De hinder som identifierades var svårigheter att definiera engångs-, respektive flergångskassar, samt bristen på synkronisering eller kombination med andra styrmedel. De drivkrafter som identifierades relaterade till organiseringen och kommunikationen mellan de berörda verksamheterna, till trots förbättringsmöjligheter för dessa aspekter. En av slutsatserna är att styrmedel som detta bör nyttja både ett teknocentriskt perspektiv om plastbärkassens miljö-, och klimatpåverkan, samt ett socioekonomiskt perspektiv utgående från berörda verksamheter och organisationers behov. / The Swedish tax on plastic carrier bags that was implemented in 2020 was initially met with dissatisfaction from the public and stakeholders. Current research investigating the tax on plastic carrier bags was done in other countries and is focused on the reactions and behaviours of consumers. Thus, this study investigates stakeholders’ reasoning around the implementation of the tax as well as its results. Another aim is to identify obstacles and driving forces for the implementation. To do so, an explorative approach in combination with interviews of stakeholders were used. The results show that implementation was met with dissatisfaction by half of the participants in the study, owing to the singular aim of the tax. The other half of participants viewed the tax purpose as satisfactory. The obstacles that were identified was difficulties in distinguishing single-use from multi-use plastic carrier bags, as well as the lack of synchronization or combination with other measures. The driving forces that were identified related to the organization and communication between stakeholder, despite opportunities for improvement. One of the conclusions of the study was that policy measures like this tax should use a technocentric perspective on the environmental impact of the plastic carrier bag, in combination with a socioeconomic perspective on the needs of stakeholders.
86

Plan de Negocio para la distribución de bolsas de papel reciclado como medio publicitario en bodegas, mini-markets y puestos de mercado de Lima Metropolitana / Business Plan for a company that distributes recycled paper bags as printed advertising in grocery stores, mini-markets and market stalls in Lima.

Noguera de las Casas, Ana Vanessa, Orams Camacho, Edgar Alfred, Perea Isasi, Cinthya Paola 27 August 2020 (has links)
A través del presente trabajo de investigación, buscamos sustentar la deseabilidad, viabilidad y rentabilidad del Modelo de Negocio de Innobag Perú, que tiene como objetivo la distribución gratuita de bolsas de papel reciclado con publicidad impresa a bodegas, mini-markets y puestos de mercado en Lima Metropolitana. Innobag Perú busca contribuir con la reducción en el consumo de bolsas plásticas, atacando y aprovechando uno de los principales momentos de uso, generando ahorros en los establecimientos e incrementando la atractividad de nuestro producto. Completamos nuestra propuesta de valor, convirtiendo estas bolsas de papel reciclado en un medio para que las empresas anunciantes publiciten su marca de manera efectiva y directa en un momento de alto uso asegurando la viabilidad de nuestro modelo de negocio. A través de un sondeo realizado entre consumidores, administradores de bodegas, mini-markets y puesto de mercado; y decisores de inversión en publicidad de empresas anunciantes, hemos logrado validar la deseabilidad de nuestro modelo de negocio. Nuestro análisis económico financiero, nos ha permitido validar la rentabilidad del modelo, esperando un VAN de S/ 114,202 y una TIR de 81.26%. / Through this research work, we seek to support the desirability, feasibility and profitability of the Innobag Peru Business Model, which aims to distribute free recycled paper bags with printed advertising to grocery stores, mini-markets and market stalls in Lima. Innobag Peru seeks to contribute to the reduction in the consumption of plastic bags taking advantage of one of the main moments of its use, generating savings for the owners of these establishments and increasing the attractiveness of our product. We complete our value proposition by turning these recycled paper bags into a mean for companies to advertise their brand effectively and directly at a time of high use, ensuring the viability of our business model. Through our market research conducted among consumers, decision makers of investment in advertising as well as managers of grocery stores, mini-markets and market stalls, we have validated the desirability of our business model. Our financial and economic analysis allowed us to validate the profitability of the model, expecting an NPV of S / 114,202 and an IRR of 81.26%. / Trabajo de investigación
87

El impuesto al consumo de las bolsas de plástico y su impacto financiero y tributario en los supermercados de lima metropolitana, año 2019 / The tax on the consumption of plastic bags and its financial and impact in the supermarkets of Lima Metropolitan, Year 2019

Eugenio Quispe, Nathaly Alejandra, Rodríguez Gutiérrez, Roxana Maribel 17 August 2021 (has links)
La presente investigación busca analizar el impacto financiero y tributario que tiene el Impuesto al Consumo de las bolsas plásticas en los agentes de percepción, tomando como estudio los supermercados de Lima Metropolitana, año 2019. Se busca conocer el proceso de sensibilización que el gobierno ha venido llevando a cabo para la concientización de los consumidores sobre los beneficios que conlleva principalmente al medio ambiente de gravar con un impuesto a las bolsas plásticas y el grado de afectación que este tiene en todos los agentes involucrados. La aplicación del presente impuesto busca aparte de generar una fuente de ingreso al fisco, la reducción, y posterior desaparición del consumo de plástico. Para la investigación hemos planteado la situación problemática, los objetivos e hipótesis y las limitaciones y parámetros. En cuanto a la metodología de la investigación hemos desarrollado el objetivo y nivel de la investigación, diseño de la investigación, investigación cualitativa, cuantitativa, como las técnicas para el procesamiento y análisis de la información, y la matriz de operacionalización de las variables. En el desarrollo se han consultado diversas fuentes bibliográficas y se ha investigado los pareceres sobre el particular de los gerentes financieros y personal contable. Además, se ha consultado con expertos en temas tributarios y financieros para la validación de las encuestas, planteamos un caso práctico aplicado a una empresa para el mejor entendimiento de la investigación. Por último, tenemos el análisis de los resultados donde muestra detalladamente con gráficos los resultados de las encuestas, el análisis del estudio cualitativo y cuantitativo, las dimensiones y del caso práctico a través de gráficos. / This research seeks to analyze the financial and tax impact that the tax on the consumption of plastic bags has on withholding agents, taking as a study the supermarkets of Metropolitan Lima, year 2019. It seeks to know the sensitization process that the government has been carrying out for the awareness of consumers about the benefits that it entails mainly to the environment of recording with a tax on plastic bags and the degree of affectation that this has in all the agents involved. The application of this tax seeks, apart from generating a source of income to the treasury, the reduction, and subsequent disappearance of plastic consumption. For the investigation we have raised the problematic situation, the objectives and hypotheses and the limitations and parameters. Regarding the research methodology, we have developed the objective and level of the research, research design, qualitative and quantitative research, such as techniques for information processing and analysis, and the operationalization matrix of the variables. During the development, various bibliographic sources have been consulted and the opinions of financial managers and accounting personnel have been investigated on the matter. In addition, we have consulted with experts in tax and financial issues for the validation of the surveys, we present a practical case applied to a company for a better understanding of the investigation. Finally, we have the analysis of the results where it shows in detail with graphics the results of the surveys, the analysis of the qualitative and quantitative study, the dimensions and the practical case through graphics. / Tesis
88

Diseño y construcción de vivienda unifamiliar para bajas temperaturas con sacos de tierra y revestimiento de totora en la región de Puno

Rojas Velasquez, Josias Eleazar, Arce Barriga, Marco Antonio 15 July 2021 (has links)
Este trabajo de investigación presenta un diseño y posteriormente, la construcción de una vivienda unifamiliar a base de bolsas de tierra con un revestimiento interno de totora. Esta tesis tiene como objetivo poder brindar un diseño de vivienda que sea económico, estructuralmente estable, fácil de construir y, sobre todo, que sea un aislante térmico para las bajas temperaturas en época de heladas en la región de Puno. En la introducción, se plantea el problema actual de las viviendas rurales en el departamento de Puno y los datos de temperaturas y de población de la región de Mazocruz. El primer capítulo desarrolla el marco teórico de la investigación concerniente a la tierra como principal material para la estructura, la totora y sus propiedades de aislante térmico y, sobre el sistema de calefacción “Piso Kang”. Luego, en el segundo capítulo se explica la metodología de investigación y artículos científicos relevantes. El tercer capítulo abarca la verificación de estabilidad estructural del diseño de vivienda que se construyó. Posteriormente en el cuarto capítulo se explica a detalle cómo es la propuesta de diseño de la vivienda unifamiliar, considerando encuestas a pobladores de la zona para una distribución arquitectónica adecuada. En el quinto capítulo se presentan los métodos utilizados para el revestimiento con totora y el “Piso Kang” como sistema de calefacción natural. Luego, el sexto capítulo muestra el entregable final de este trabajo, que es una guía de construcción de esta vivienda para bajas temperaturas. En las conclusiones se presentan los resultados finales obtenidos luego de la construcción de la vivienda unifamiliar. Además, se presentan las recomendaciones para el desarrollo de futuras tesis de grado en esta línea de investigación. / In this research work a design is presented and later, the construction of a single-family dwelling based on earth bags with an internal “totora” coating. This thesis aims to provide a housing design that is economically, structurally stable, easy to build and, above all, that is a thermal insulator for low temperatures during the frost season in the Puno region. In the introduction, the current problem of rural housing in the department of Puno and the temperature and population data of the Mazocruz region are raised. In the first chapter, the theoretical framework of the research concerning the earth is presented as the main material for the structure, the “totora” and its properties as thermal insulating material and the method of natural heating called “Kang Floor”. Then, the second chapter is about the research methodology and the selection criteria of scientific articles and past research works that were of great contribution to this research is explained. The third chapter covers the verification of structural stability of the single-family housing design that was built. Later in the fourth chapter, is explained in detail how the design proposal of the single-family home was developed, taking as reference surveys conducted in the field, concluding in a right architectural distribution. In the fifth chapter, the methods used for totora cladding and the “Kang Floor” as a natural heating system are presented. Then, in the sixth chapter the final deliverable of this research work is developed, which is the guide for the construction of a single-family house for low temperatures. The conclusions show the results obtained after the construction of the single-family home. In addition, the appropriate recommendations for the development of future thesis in this line of research are presented. / Tesis
89

The impact of selective beech (Nothofagus spp.) harvest on litter-dwelling invertebrates and the process of litter decomposition

Evans, Alison January 1999 (has links)
Minimising the potential impact of forest management requires an understanding of the key elements that maintain forest diversity and its role in ecological processes. Invertebrates are the most diverse of all biota and play important roles in maintaining forest processes. However, little is known about invertebrates in New Zealand's beech forests or the degree to which selective beech harvest might impact on their diversity and ability to carry out ecosystem processes. Studying ecosystem responses to disturbance is considered vital for understanding how ecosystems are maintained. One of the main objectives of this research was to assess whether litter-dwelling invertebrates were susceptible to the impacts of selective harvest and, if so, whether they could be used as indicators of forest health. Changes in invertebrate diversity could have important implications for nutrient cycling and primary production in forests. Litter-dwelling invertebrates contribute to the process of decomposition by increasing the surface area of the leaves, mixing soil organic matter and by infecting leaf particles with soil microbes. This investigation into the function of invertebrates in beech forest was carried out in the context of ecological theories which relate diversity to ecosystem stability and resilience. A replicated study was established in Maruia State Forest (South Island, New Zealand) to assess the potential biotic and abiotic impacts of sustainable beech harvest. Litter-dwelling invertebrates and environmental factors were monitored during 1997, before harvest, to determine how much variability there was between study sites. Specifically, litter pH, light intensity, litter fall, litter temperature, moisture as well as invertebrate abundance and diversity were compared before and after selective harvest. On 17 January 1998, two to three trees were selectively harvested from three of the nine study sites. On 15 February 1998 a similar number of trees were winched over or felled manually to create artificial windthrow sites. The remaining three undisturbed sites were used as controls. Invertebrates belonging to the detritivore guild were assessed from litter samples and a series of litter-bags containing pre-weighed leaf litter which were placed in each of the sites to assess rates of litter decomposition. Millipedes (Diplopoda: Polyzoniidae, Schedotrigonidae, Dalodesmidae, Habrodesmidae, Sphaerotheridae), earthworms (Oligochaeta: Annelida), tipulid larvae (Diptera: Tipulidae), weevils (Coleoptera: Curculionidae), moth larvae (Lepidoptera: Oecophoridae, Tortricidae and Psychidae), slaters (Isopoda: Styloniscidae), Oribatid mites (Acarina: Cryptostigmata) and landhoppers (Crustacea: Amphipoda) were extracted from the litter-bags and their abundance and diversity was compared between the three treatments. Weight loss from the litter-bags and the carbon and nitrogen content of litter were used to measure the rate of decomposition in each treatment. An additional study investigated whether exclusion of invertebrates from leaf litter resulted in reduced rates of decomposition. The results indicated that there was an increase in light intensity and a small increase in temperature following selective harvest and artificial windthrow. There was no significant difference in litter moisture or the amount of litter fall between the treatments. Invertebrate abundances were significantly affected by season but did not appear to be affected by selective harvest or artificial windthrow. The diversity of invertebrates remained relatively constant throughout the year, as did the rate of decomposition. When invertebrates were excluded from the leaf litter there was no consequential effect on the rate of litter decomposition. This suggests that there may be compensatory mechanisms taking place between the trophic levels of the food web to maintain processes and that direct links between invertebrates and decomposition are relatively weak. In conclusion, it appears that the effects of selective beech harvest on forest-floor processes were minimal and are comparable to those created by natural windthrow disturbance. It also appears that macroclimatic effects such as seasonal climatic effects have a large effect on forest biota. As none of the invertebrates studied appeared to be detrimentally affected by selective harvest and as there was no direct link demonstrated with decomposition, it was considered inappropriate to advocate the use of this group of invertebrates as indicators of sustainable forest management. The results from this study provide information which may help inform decisions on the future management of diversity in beech forest ecosystems.
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DESIGN AND FABRICATION OF FLEXIBLE SENSORS FOR SINGLE-USE APPLICATIONS

Aiganym Yermembetova (13954878) 13 October 2022 (has links)
<p>The development of reliable, robust and low-cost sensor devices is growing in importance and an ongoing challenge. From environmental monitoring and household safety to food and biopharmaceutical industries, the necessity for specific analyte detection is crucial. Over the years researchers have come up with myriad materials that can be used for efficient sensing devices. The materials employed are governed by application and performance criteria as well as the sensing mechanism, which might be based on physical or chemical principles. In this thesis, two different types of electrochemical sensor technologies were examined with special attention paid to the application of the devices, the materials used, and their feasibility for scalable manufacturing.</p> <p>In the first study, binary mixtures of conducting and semiconducting nanomaterials were explored as promising candidates for the manufacturing of low-cost ethylene sensor on flexible substrates. Ethylene (C2H4) is a small plant hormone which has been shown to affect the growth and senescence of flowers, leaves and fruits. Currently available devices have demonstrated high ethylene sensitivities with great potential for technology size reduction; however, some are not practical for use outside of the laboratory, lack portability, or require more research to demonstrate their reproducibility and stability in different environments, as well as selectivity to C2H4 in large-scale applications. Conductometric gas sensors based on a combination of carbon nanotubes (CNTs) and exfoliated molybdenum disulfide (MoS2) coated with molecular receptors is demonstrated for the selective detection of ethylene, including details on materials preparation, manufacturing, and characterization. Mixtures of CNTs and exfoliated MoS2 were deposited onto screen-printed interdigitated electrodes on plastic substrates, with optimization for scalable and continuous manufacturing by roll-to-roll methods. C2H4 detection levels of 0.1 ppm were readily achieved with responses on the second timescale.</p> <p>The second sensor technology shows how thin-film potentiometric electrodes based on ion-selective membranes can be designed to tolerate sterilizing radiation while providing excellent performance and signal stability. This sensor's development was motivated by the expanding need for single-use bioreactor systems in the biopharmaceutical industry, which require strict control over cell culture conditions for several weeks or more. Until recently, critical analysis has been conducted mostly by offline or “at-line” sampling of aliquots withdrawn from the sterile bioreactor. The latter is inefficient and can increase the risk of contamination. Inspired by the challenges related to cost, integration and performance following irradiation a potentiometric pH electrode was developed, intended for single-use applications. It was shown to be radiation-tolerant while providing reliable data comparable to a commercial pH meter over a period of three months. The electrodes exhibited quasi-linear signal drifts of +0.28 mV/day or 0.005 pH units/day. Thin-film γ-irradiated electrodes could provide accurate pH readings in sterilized culture media using a single-point calibration, within 0.07 pH units of a commercial meter with glass electrode and daily calibration. Furthermore, to advance the development of market-ready sensors past the conceptual stage, a few automated processes for scalable membrane deposition were investigated.</p>

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