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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.
101

A decentralized look to cartels prosecution in Peru / Una mirada descentralizada al enjuiciamiento de cárteles en el Perú

Quintana Sánchez, Eduardo 10 April 2018 (has links)
This paper analyses how IndecopI has prosecuted and sanctionedcartels within the country, taking into account whether economic agents have internalized the extent and impact of the ban of cartels and the type of reaction deployed by the authority over time. / En este trabajo se analiza cómo ha perseguido y sancionado el Instituto Nacional de Defensa de la Competencia y de la Protección de la Propiedad Intelectual (IndecopI) las prácticas colusorias  de  competidores que han tenido lugar en el interior del país, considerando si los agentes económicos de esas zonas han internalizado el alcance y las consecuencias de la prohibición de tales prácticas, así como el tipo de respuesta que ha tenido la autoridad a lo largo del tiempo.
102

Modélisation climatique à l’échelle des terroirs viticoles dans un contexte de changement climatique / Climate modeling at vineyard scale in a climate change context

Le Roux, Renan 08 December 2017 (has links)
À l’échelle d’un terroir viticole, le climat présente des variations significatives et joue un rôle important sur les caractéristiques des vins produits. L’adaptation de la filière viticole au changement climatique en cours nécessite la connaissance de l’évolution du climat à l’échelle locale. Cette étude vise à intégrer cette échelle dans les projections climatiques en se basant sur l’utilisation combinée de modèles dynamiques et géostatistiques. Dans un premier temps, l’utilisation d’un modèle climatique régional à haute résolution (1 km) dans les vignobles de Marlborough (Nouvelle-Zélande) a permis de cartographier les températures d’une région viticole. Les limites et les incertitudes de l’utilisation de ce type de modèle, notamment pour la représentation des variations thermiques les plus locales, ont également été étudiées. Par l’utilisation des données issues d’un réseau dense de capteurs de température, une seconde étape a consisté au développement d’un modèle statistique non linéaire permettant une cartographie fine des températures sur les appellations Saint-Émilion, Pomerol et leurs satellites. Enfin une méthode d’intégration de l’échelle locale dans les projections de changement climatique est proposée, associant modèles dynamiques et modèles géostatistiques. Cette thèse a mis en évidence que l’utilisation simultanée de différentes méthodes de modélisation des températures peut représenter une piste intéressante pour pallier aux manques qu’elles peuvent représenter individuellement et limiter ainsi l’incertitude. / At vineyard scale, climate variability can be significant in magnitude and play a key role in vine and wine characteristics. Adaptation of viticulture to climate change requires knowledge about future fine-scale climate evolution. This study aims to integrate local scale in future climate projections, coupling dynamic and statistical modelling. A first step consisted in producing temperature maps at 1 km resolution using WRF in a vineyard area (Marlborough, New-Zealand) and evaluating model uncertainties. It revealed that dynamical models do not represent well local climate variations. Using a high density temperature data logger network, the second part is dedicated to developing a non-linear statistical model to map temperature at very fine scale in famous sub-appellations of the Bordeaux vineyard area (Saint-Émilion). Following, a method, coupling dynamical and statistical modelling, is proposed to integrate local scale in climate change projections. This thesis highlights that using simultaneously statistical and dynamical models can be an approach to reduce model uncertainties.
103

Desenvolvimento de briquetes autorredutores a partir de carepas de processamento siderúrgico para utilização em forno elétrico a arco

Buzin, Pedro Jorge Walburga Keglevich de January 2009 (has links)
A indústria siderúrgica do Estado do Rio Grande do Sul é do tipo semi-integrada e produz aço a partir de sucata, utilizando fornos a arco elétrico. Em suas atividades gera vários tipos de resíduos, dentre estes as carepas, cujo componente principal são óxidos de ferro. Este material não encontra utilização e geralmente tem destinação final em aterros de resíduos industriais ou co-processamento em fábricas de cimento. A produção e o processamento do carvão vegetal no estado do Rio Grande do Sul também geram como principal resíduo uma fração de baixa granulometria constituída de finos de carvão vegetal que praticamente não tem utilização e é descartada no meio ambiente. O objetivo do presente trabalho é buscar uma solução para a reciclagem de carepas geradas em usinas semi-integradas dentro do próprio processo produtivo. A solução proposta foi o desenvolvimento de um briquete autorredutor elaborado com carepa de aciaria e finos de carvão vegetal, com possibilidade de utilização na carga do forno elétrico à arco. Carepas e finos de carvão vegetal foram coletados e caracterizados. Briquetes autorredutores foram feitos com estes materiais e submetidos a ensaios de redução nas temperaturas de 1100, 1200 e 1260°C. O comportamento dos briquetes em altas temperaturas foi qualitativamente avaliado. Cálculos matemáticos e simulação computacional foram utilizados numa estimativa do consumo energético destes briquetes. O desempenho dos briquetes e os resultados obtidos permitem concluir pela potencialidade de utilização destes briquetes autorredutores como parte da carga de fornos elétricos a arco. / The steelmaking industry in Rio Grande do Sul State is semi-integrated and produces steel from scrap metal using electric arc furnaces. In its activities generates several wastes, among them mill scale, which main component are iron oxides. This material does not have use and generally have final destination in industrial landfills or co-processing in cement plants. The production and processing of charcoal in Rio Grande do Sul State also generate as main waste a fraction of low granulometry, consisting of charcoal fines what practically have no use and is disposal in the environment. The objective of the present work is to look for a solution to mill scale recycling, generated in semi-integrated steelmaking plants, inside its own productive process. The proposed solution was the development of self-reducing briquette produced with mill scale and charcoal fines, with possibilities of use in charge of electric arc furnace. Mill scale and charcoal fines were collected and characterized. Self-reducing briquettes were made from these materials and subjected to tests of reduction at temperatures of 1100, 1200 and 1260°C. The behaviour of briquettes in high temperatures was qualitatively evaluated. Mathematical calculation and computational simulation were used in a estimative of the energetic consumption of these briquettes. The performance of briquettes and the obtained results allow to conclude the potential use of these self-reducing briquettes as a part of charge in electric arc furnaces.
104

An Investigation of the Effects of Chemical and Physical Weathering on Submerged Karst Surfaces

Booth, Bryan Charles 08 December 2015 (has links)
Reports an investigation of the effects of chemical and physical weathering on submerged karst surfaces that pairs laboratory studies with computer modeling studies. The first study attempts to quantify the production of carbonate fines; soluble sediments produced by the incomplete dissolution of karst minerals during chemical weathering. Results show carbonate fine production in relation to dissolutional action; Chalk: 42.8%; Coquina: 2.6%; Dolomite: 3.1%; Gray Limestone: 4.8%; Ocala Limestone: 3.1%; Shell Limestone: 6.1%; Travertine: 8.6%. Due to the use of hydrochloric acid as opposed to carbonic acid these results may not be fully valid for application to natural speleogenic processes. The Limestone Weathering Model, a numerical-computer model, was developed using these experimental findings as minimal values compared with published rates. Reported as the actual volume of rock mass lost to both dissolution and to carbonate fine production, the rates for carbonate fine production ranged from 5.8% to 10.9% (year 1- 5.8%, year 2- 8.5%, year 3- 9.7%, year 4-10.3%, year 5- 10.9%), with a mean value for carbonate fine production of 9%, but a continuing rate after five years approaching 11%. The second study uses metrological laser scanning to measure the erosive loss due hydraulic shearing force and corrasion on submerged limestone surfaces. The rates for material removed using increasing velocity values (0.3m/s, 0.5m/s, 1.0m/s, 1.5m/s, 2.0 m/s, 2.5m/s) during flow durations of less than 6 minutes duration were : 1) Hydraulic shearing force- 0.3µm/s, 0.5µm/s, 0.4-1.7µm/s, 2.5 µm/s, 5.5 µm/s, 2) Corrasion- 0.3 µm/s, 0.7 µm/s, 1.5 µm/s, 1.5-1.8 µm/s, 8.9 µm/s, 8.1 µm/s. The study model was modified to return these rates for hydraulic shearing force limited by the depth of the chemical corrosion of the surface. The model returns % rock volume lost to hydraulic shearing force compared to dissolutional rate (1mm/y) for 3 flow velocities (0.03m/s<, 1.0m/s<, 2.5m/s<) on 4 timing schedules: Annual 7.8,14.3,19.6, Semiannual 21.1,21.1,69.7, Quarterly- 32.8,43.6, 70.9, Monthly- 80.0, 109.3, 200.3. Model demonstrates significant effect (7.8% to 200% over dissolutional rate) on speleogenic rates from even infrequent, moderate changes in flow velocities due to storm events. Study’s results support the significance of chemical weathering by disaggregation and physical weathering by hydraulic shearing force as major factors in the processes of karst speleogenesis.
105

Diseño de una Metodología de Evaluación de los Proyectos de Voluntariado de la Fundación América Solidaria

Tupper Hernández, Francisco Javier January 2011 (has links)
No description available.
106

Interactions between fibres, fines and fillers in papermaking:influence on dewatering and retention of pulp suspensions

Liimatainen, H. (Henrikki) 08 September 2009 (has links)
Abstract Interactions between the components of papermaking suspensions (e.g. fibres, fillers, fines and polymers) have a remarkable effect on various unit processes in papermaking. The filterability of fibre suspensions, which is a crucial property for example in paper sheet forming and solid recovery, is also known to be depended on particle interactions. However, due to the complex nature of the interactions, the role of these phenomena in fibre suspension filtration is still not fully understood. The focus of this thesis was to find out how phenomena associated to fibre flocculation, fibre deflocculation and filler particle deposition affect the filterability of fibre suspensions in terms of their dewaterability and retention. It was shown that the influence of fibre flocculation on dewatering is closely related to the structure of fibre flocs. More importantly, the internal density of flocs and factors that impacted the packing structure of filter cakes, such as floc size, played a crucial role in fibre suspension dewaterability. Dense flocs with a low internal porosity particularly induces fast water flow by a mechanism termed as the “easiest path mechanism” through the large voids around the flocs. The effect of fibre suspension dispersing on dewaterability and particularly fines retention was found to be associated to the mechanism of action of the deflocculation agent. Carboxymethylcellulose (CMC), the deflocculant used in this study, had detrimental effects on the dewatering of a pulp suspension both when being adsorbed on fibre surfaces and when remained in the liquid phase. However, adsorbed CMC causes more plugging of the filter cake because it disperses the fines more profoundly. Thus the adsorbed CMC also reduces fines retention considerably more than CMC did in the liquid phase. Filler deposition and retention was found to be significantly higher on pulp fines fractions of mechanical and chemical pulp than on fibre fractions due to the higher external surface area of fines. The surface charge densities of pulp fractions also affected their ability to adsorb fillers. Cationic charges of filler particles was in turn observed to induce deposition of fillers on fibre surfaces which increased retention but also the dewaterability of a fibre suspension due to a decrease in total surface area of a suspension.
107

Photon migration in pulp and paper

Saarela, J. (Juha) 07 December 2004 (has links)
Abstract The thesis clearly demonstrates that photon migration measurements allow characterization of pulp and paper properties, especially the fines and filler content of pulp, and the basis weight, thickness and porosity of paper. Pulp and paper are materials with a worldwide significance. Their properties strongly depend on the manufacturing process used. For efficient process control, the employed monitoring and measuring has to be fast. Therefore it is worthwhile to try to develop new approaches and techniques for such measurements. Recent advancements in optics offer new possibilities for such development. If two samples have different optical properties their photon migration distributions are different. The measurement of a photon migration distribution allows some features between two optically slightly dissimilar samples to be distinguished. Some simple measurements, which only yielded the photons' average time of flight, were made with an oscilloscope and a time-of-flight lidar. More precise measurements yielding photon pathway distribution or some selected characteristics like light pulse rise time, broadening, or fall time were measured with a streak camera. Two methods to assess photon path length distribution were introduced: particle determination with simulation, and streak camera with deconvolution. The basic properties for pulp are consistency and fines content and for paper the basic properties are thickness, basis weight and porosity. The influence on photon migration caused by changes in these basic properties was determined. As pulp and paper are rarely very basic, an additional property was demonstrated for both materials. For pulp it was the content of filler talc, and for paper it was the use of beaten pulp as a raw material. These additional properties were also distinguishable.
108

Adaptabilidad del estilo de liderazgo en voluntarios de una organización sin fines de lucro

Pereda Torres, Gavina Beatriz January 2018 (has links)
El estudio es descriptivo comparativo que aborda el tema de la adaptabilidad, también llamada efectividad, del estilo de liderazgo bajo el enfoque de la Teoría de Liderazgo Situacional de Hersey y Blanchard, en voluntarios de una organización no gubernamental sin fines de lucro. Para la identificación de los estilos de liderazgo y su adaptabilidad se utilizó el Test LEAD en su formato de autopercepción. Los resultados indican que el estilo de liderazgo predominante en el grupo de voluntarios es el Persuasivo, en tanto que el nivel de adaptabilidad general es medio bajo; asimismo se identificaron diferencias estadísticamente significativas según la variable “Participación en Intercambios”. Palabras clave: Liderazgo, Estilos de liderazgo, Liderazgo Situacional, Voluntariado, Organización no lucrativa, ONG. / Tesis
109

Gestión administrativa y marketing estratégico en la Institución Educativa Nº 2071 César Vallejo, distrito de Los Olivos, Lima Norte 2017

Alvarez Moreno, Angela Alejandrina January 2019 (has links)
Determina la influencia de la gestión administrativa en el marketing educativo. Para la prueba de hipótesis se aplicó el SPSS 24 el cual arrojó relación positiva a favor de la hipótesis general, por ello se concluyó que la Gestión Administrativa se relaciona positivamente con el marketing educativo estratégico. Actualmente las instituciones educativas públicas no precisan reales gestiones administrativas de marketing estratégico educacional hacia los alumnos; ya que muchas veces, no cuentan con una visión competitiva frente a los servicios que brinda las instituciones educativas privadas. Por ello, la presente investigación determinó la relación significativa de la gestión administrativa y el marketing estratégico de la Institución Educativa N° 2071 César Vallejo, distrito de Los Olivos, Lima Norte - 2017, con el diseño No experimental transversal de tipo básica con el método Correlacional. La población fue de 1,375 personas entre Directivos, Administrativos, Docentes, Padres de Familia y Alumnos, de los cuales se seleccionaron como muestra no probabilística (385) bajo el procedimiento de Fisher, Arkin y Colton. Se aplicó un instrumento por variable; encuesta de gestión administrativa y marketing educativo. Se aplicó la escala de Likert en esta investigación. / Tesis
110

Teorías de los fines de la pena: la problemática aplicación de la prevención especial en la política criminal peruana / Theories of punishment: the problematic application of the individual prevention in the peruvian criminal policy

Farfán Ramírez, Fabrizio Gabriel 14 July 2021 (has links)
Debido al existente monopolio punitivo y penitenciario en el Perú, y en gran parte del mundo, los Estados deben justificar mediante una finalidad, el daño que la imposición de una pena causa en el individuo. Ante ello, la política criminal peruana opta por acoger una teoría ecléctica, cuyo mayor relieve se encuentra en la prevención especial. Sin embargo, pese a ser la prevención especial el núcleo de la teoría acogida, este precepto no se ve correctamente materializado. El presente artículo desarrolla el fundamento y los problemas de las diversas teorías de los fines de la pena, las cuales se presentan como una opción de aplicación para el legislador peruano. Analiza, además, la estigmatización, la presión mediática y el exceso de privaciones de libertad. Problemas que impiden la materialización de la prevención especial en el Perú. / Due to the punitive and penitentiary monopoly in Peru, and in much of the world, States must justify, through a purpose, the damage that the imposition of a penalty causes in the individual. Given this, the Peruvian criminal policy chooses to embrace an eclectic theory, whose greatest importance is found in individual prevention. Nonetheless, despite individual prevention being the core of the accepted theory, this precept does not appear to be properly materialized. This article develops the foundation and problems of the various theories of the punishment, which are presented as an application option for the Peruvian legislator. It also analyses stigmatization, media pressure and excessive deprivation of liberty. Problems that prevent the materialization of individual prevention in Peru.

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