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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.
201

Plan de negocio para la creación de una planta purificadora de agua: San Jorge

Ortiz Porras, Jorge, Roque Huayra, Doris, Goyburu Naquiche, Isabel 08 March 2016 (has links)
El agua es un recurso natural que se agota en el tiempo. Agua San Jorge nace como una necesidad de satisfacer la demanda creciente de agua de mesa con un alto grado de purificación en los hogares, y las empresas. La Motivación para poder ejecutar la idea de negocio es que hay un mercado insatisfecho que crece año a año, lo cual es una excelente oportunidad para llevar adelante el proyecto. A eso se suma la desconfianza de la población frente a los sistemas de redes de distribución de agua que no tienen un mantenimiento permanente de tal manera que el agua que se dice ser potable realmente llega a los hogares con una calidad inadecuada para ser directamente bebida; el ama de casa típicamente hierve el agua para su consumo teniendo que eliminar las bacterias y reduciendo en algo la dureza del agua; sin embargo no la elimina completamente esta dureza y el contenido metálico del agua no se elimina por calentamiento, produciéndose durante el consumo la acumulación de metales en el organismo que a la larga producen enfermedades.[1]. La Contribución económica y social de tomar agua purificada produce un ahorro en la economía del hogar, puesto que el ama de casa dejara de hervir el agua para poder servirse un desayuno, almuerzo, cena o al prepararse un refresco; también mejora grandemente la salud de la población. Además desde hace algunos años hay una clara tendencia de los consumidores hacia productos funcionales (que tienen propiedades positivas para la salud). Ello ha impulsado a un mejor desempeño de productos como agua embotellada, té bebible y energizantes, frente a las bebidas gaseosas azucaradas. / Tesis
202

Circular Inspirations: Medieval Mediterranean Influence in the Treasury of San Marco

Rasmussen, Claire January 2019 (has links)
No description available.
203

The Church of San Cayetano de la Valenciana, Guanajuato, Mexico: a Study of its Mexican Churrigueresque Architecture and Decoration

Quantz, Pamela A. (Pamela Ann) 05 1900 (has links)
This study is devoted to a critical examination of the architectural structure and sculpture of the church of San Cayetano de La Valenciana in Guanajuato, Mexico, concentrating on the ornamentation of the exterior portals and the interior altar retables. This paper traces the development of the Churrigueresque phase within the Baroque period of Mexican religious architecture and analyzes specific application of this style to the church of La Valenciana. Stylistic and iconographic components are discussed and a review of significant literature on this subject is included.
204

Hydrologic Modeling of the San Joaquin Valley Watershed for Purposes of Nitrate Analysis

Clayton, Stephen Carl 01 March 2013 (has links) (PDF)
The San Joaquin Valley is regarded as one of the most productive agricultural regions in the world. This extensive agriculture has, however, caused extensive pollution of both ground water and surface water. This thesis develops a hydrologic model of the surface and ground waters of the San Joaquin Valley. Such modeling is useful in the development and implementation of water quality regulations such as Total Maximum Daily Loads (TMDLs). A properly validated watershed simulation model can supplement data collection and can account for watershed characteristics including topography, soils, climate, land cover, anthropogenic activities, as well as simulate watershed responses including streamflow and contaminant concentration at detailed spatial and temporal scales. Models can be used as a decision support tool to manage complex agricultural watersheds such as the San Joaquin Valley. Once developed, such watershed simulation models can be used to identify contaminant source areas, locate hot-spot areas that have high pollution risk, identify optimal monitoring sites, and determine best management practices to cost-effectively reduce pollution. As a step towards developing a model as a decision making tool, the objective of this study is to appraise effectiveness of a widely used watershed simulation model known as Soil and Water Assessment Tool (SWAT) to simulate hydrology of the San Joaquin Valley watershed. For this thesis SWAT was successfully calibrated for streamflow at several locations in the watershed, thus demonstrating the capability of the model to represent the complex, snow-driven hydrology of the San Joaquin Valley watershed including dams and reservoirs located in the mountains, and agricultural activities and flow diversion systems in the valleys. Calibration of sediment and nitrate loadings in the surface waters were also attempted; the results were, however, less than convincing compared to stream flow calibration. Future studies are recommended to improve accuracy of the water quality predictions and to evaluate long-term effectiveness of various watershed management policies in improving surface water and groundwater quality in the San Joaquin Valley. The hydrology model developed in this study can be used as a foundation for future studies that focus on water quality.
205

Productivity And Modelling Of Microalgae Mono- And Polycultures Grown On Wastewater In Raceways

Scott, Michael J 01 December 2023 (has links) (PDF)
Microalgae biomass has potential as a feedstock for various bioproducts, including biofuel. Algae can be cultivated on treated wastewater or on untreated wastewater, accomplishing treatment as a co-benefit. Greater understanding of algal productivity is needed. This study compared the net productivity of naturally forming algae polycultures, and monocultures of Scenedesmus obliquus (DOE0152Z) and Tribonema minus cultivated on treated municipal wastewater or primary clarifier effluent. The experiments were conducted in outdoor, 1350-L and 1000-L, raceway tanks in coastal central California during a multi-year period. A linear regression model of net productivity (i.e., based on the difference of biomass in the influent and effluent of the raceways) was developed. The highest productivity culture was a polyculture grown on primary clarifier effluent at 20.0 +/- 3.8 g/m2-day (ash-free dry weight, AFDW over 12 months of continuous cultivation). The monoculture with the highest productivity was Tribonema minus at 16.1 +/- 0.8 g/m2-day (summer through winter). In the various strain and wastewater type combinations tested, solar radiation was the most statistically significant predictor of net productivity (p
206

Magnetic Properties of the Bishop Ash in the San Andreas Fault Borderlands

Strauss, Becky January 2011 (has links)
No description available.
207

The international relations of a metropolitan area : San Diego in the world /

Stephenson, Carolyn McGoey January 1980 (has links)
No description available.
208

Monitoring of crustal movements in the San Andreas fault zone by a satellite-borne ranging system /

Kumar, Muneendra January 1976 (has links)
No description available.
209

Geomorfología regional y dinámica costera del sector occidental del golfo San Matías

Genchi, Sibila Andrea 06 June 2012 (has links)
El objetivo general de la presente Tesis Doctoral es deter-minar y caracterizar las geoformas del Oeste del golfo San Matías, orientado a realizar una cartografía geomorfológica regional. Además, se pretende analizar la dinámica de las formas costeras. Este estudio se apoyó en el análisis de variables geológicas, climáticas e hidrográficas continental y marina para comprender las geoformas de un modo integral. El área, de aproximadamente 22500 km2, señala un estudio regional, no obstante, se abordaron dos escalas de análisis espacial: regional y local. Se efectuó una clasificación super-visada de las geoformas a escala regional. Para ello se partió de un modelo digital de elevación (MDE) -datos SRTM- sobre el cual se derivaron las variables pendiente e índice de posi-ción topográfico. Existe un predominio de las clases pendiente abierta y planicie que cubren el 45 y 33 % del área total, res-pectivamente. Las restantes clases cubren superficies meno-res: lomas, cerros y sierras (8 %); bajos, valles en V (7,5 %); valles de fondo plano (3 %) y pendiente alta (2,6 %). Se pudo observar un patrón geomorfológico diferenciado al N y S del arroyo Salado, donde el relieve refleja las formas a través de la disposición tectónica y la litología. Hacia el N, el relieve está dominado por una planicie; al S, el relieve es rugoso, con presencia de geoformas positivas dispersas en una vasta superficie. Se procesaron las estadísticas climatológicas del Servicio Meteorológico Nacional (Estación San Antonio Oeste) del período 1961-2000. El clima es semiárido (270 días secos) y templado (T anual=15,4 C). La evolución de la precipita-ción para el período 1900-2000 señaló una tendencia cre-ciente en los últimos decenios. Para estudiar en detalle el comportamiento de las variables climáticas en la región cos-tera, se instalaron dos estaciones meteorológicas automati-zadas, las cuales monitorearon en forma continua en el período 2009-2011. Las geoformas fluviales, de carácter efímero, se encuentran ampliamente esparcidas en el área de estudio. Se efectuaron análisis estadísticos estándar y mul-tivariado de los parámetros morfométricos aplicados a aquellas cuencas de drenaje exorreico de tamaño mayor a 10 km2. Además, se efectuaron ajustes en la extracción de la red de drenaje obtenida por métodos automatizados, en función de las propiedades del terreno. De acuerdo a la técnica de análisis cluster, se obtuvieron cuatro grupos de cuencas que mostraron una marcada continuidad espacial. La variable área es la que mostró mayor variación, que osciló entre 10 y 4.090 km2 -cuenca del arroyo Salado-. La densidad de drenaje media resultó baja (2 km km-2). Para el estudio de la dinámica costera se aplicaron métodos de trabajo innovadores, con ventajas económicas y operativas que permitieron estimarla con adecuada resolución espacial. Para estudiar los acan-tilados activos que bordean la localidad de Las Grutas, se empleó un sistema láser que permite obtener la topografía de una sección vertical. En una de las secciones monitoreadas se registró un retroceso que alcanzó un máximo de 0,9 m duran-te el período entre abril y septiembre del 2010. En la locali-dad de Playas Doradas, caracterizada por un tipo de costa acumulativa, se utilizó una cámara de video para digitalizar la línea de marea (o línea de igual elevación), con lo cual se obtuvieron MDEs de la zona intermareal para distintas fechas, que posibilitaron establecer balances sedimentarios. Esta investigación se completó con un análisis integral de las variables consideradas, en relación a las geoformas, con énfasis en la fragilidad, la morfodinámica, las actividades antrópicas y sus efectos actuales y potenciales. Los resul-tados de este trabajo podrán servir como base para elaborar estrategias acordes con las posibilidades de ocupación territorial de la región. Por otro lado, los métodos de trabajo empleados son variados debido a la diversidad de temáticas abordadas; estos se ajustaron debidamente a las condiciones de sitio y poseen la ventaja de ser aplicables (y adaptables) a ambientes con características similares. / The general objetive of the research is to identify and characterize the landforms in the West of San Matías gulf, aimed to produce a regional geomorphological mapping. Moreover, another objetive is to analyze the dynamics of coastal geoforms. The study included an analysis of various variables such as geological, climate and hydrographic, essential to understand the geoforms. The approximate study area is 22,500 km2 which involves a regional study, however, regional and local spatial scales analysis were considered. Classification of landforms was carried out using paramete-rization of the relief from the SRTM data digital elevation model (DEM). Digital models such as topographic position index and slope derived from elevation data were employed as a basis for classification. According to the classification proposed in the present study, the area is dominated by open slope and plain landforms, reaching 45 and 33 % of the total area, respectively. The remaining classes occupy smaller areas: ridges, hills and mountains (8 %); lows, valleys in the form of V (7.5%); flat valley bottom (3%) and high slope (2.6 %). A distinct geomorphological pattern toward North and South of Salado stream was observed, where the relief reflects their forms through tectonics and lithology. Towards the North, the relief is dominated plains; in South, the terrain is rugged, with the presence of positive landforms dispersed over a vast area. Climate statistics of Servicio Meteorológico Nacional (San Antonio Oeste Station) for de period 1961-2000 were processed. The climate is semiarid (270 dry days) and mild (T anual= 15.4 C). The temporal evolution of precipi-tation for the period 1900-2000 indicates a growing trend over recent decades. To study in detail the behavior in rela-tion to coastal climate a high temporal resolution monitoring was carried out over the period 2009-2011 in two coastal towns. For this, two automated weather stations were installed. Fluvial landforms, which have an ephemeral charac-ter, are widely scattered in the study area. Multivariate statistical analysis was carried out using morphometric para-meters, applied to watersheds (exorheic drainage) with a size greater than 10 km2. In addition, adjustments were made on the automated extraction of drainage networks, depending on the properties of the terrain. According to cluster analysis technique four groups of basins were obtained. The area was the variable that showed the greatest variation, which ranged from 10 to 4,090 km2 (Salado basin). The average drainage density in this region was low (2 km km-2). A study was made of the dynamics processes in the coastal environmental, in which innovative methods were applied to estimate them with high spatial resolution. These methods have economic and operational advantages. A method was developed to evaluate active cliffs at Las Grutas town, based on a laser system that allows to obtaine topographic profiles with high resolution. One of monitored sections showed a retreat that reached a maximum of 0.9 m between April and September 2010. In Playas Doradas town, a video camera was used to digitize the tide line (or line of equal elevation); so DEMs were obtained at different dates, which allowed establishing sediment ba-lances in the intertidal zone.This research was completed with an integral analysis of the variables considered here, in relation to landforms, with emphasis on fragility, morphody-namics, human activities and their current and potential effects. The results of the present investigation may was undertaken to establish strategies of develop consistent with the possibilities of territorial occupation. In addition, a variety of methods were used for this study due to the diversity of topics; these were adjusted to site conditions and should be equally applicable (and adaptable) to environments with similar characteristics.
210

Enclosure

Steltzer, Derrick 15 September 2004 (has links)
This thesis proposes an urban hybrid within the historical district of downtown San Francisco. The design develops a new typ of urban housing introducing the architectural concept of the house to the highrise. / Master of Architecture

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