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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.
1

PrePro2004: a data model with pre and post-processor for HEC-HMS

Agrawal, Ashish 01 November 2005 (has links)
This thesis presents the design concepts and development of an interface (Pre- Pro2004) utilizing geodatabases for the Hydrologic Modeling System (HMS) of the Hydrologic Engineering Center (HEC). HMS is a rainfall-runoff model which supports lumped-parameter as well as distributed-parameter based modeling. PrePro2004 uses the spatial-analysis as well as data handling capabilities of ArcGIS. The spatial data are processed to create input files for HMS. These input files and the output from HMS are stored in two geodatabases which were developed using data model concepts. The tools are provided to reproduce an HMS model from the data inside these geodatabases. The interface is developed based on the DataCentric approach which brings different hydrologic and hydraulic models together. This approach aims to attain a long-term goal of utilizing the same data for different hydrologic or hydraulic models with additional model specific requirements. Two case studies are presented to show the applications of the tools developed. The first case study details the creation of HMS input files for Salado Creek watershed with Digital Elevation Model as input. It includes the importation of an existing HMS model for Salado Creek watershed as Appendix C. The second case study details the creation of HMS input files for the Bull Creek watershed, with land use and soil type data as inputs. It describes the capabilities of tools developed in detail.
2

Studie srážko-odtokových poměrů pro územní plán obce Václavov

Kmeť, Milan January 2012 (has links)
No description available.
3

Organic functionalisation of hexagonal mesoporous silica

Jackson, Dominic January 2001 (has links)
No description available.
4

Trådlös kommunikation för Anybus

Heigren, Robert, Otterdahl, Björn January 2007 (has links)
<p>The industry struggles with problems concerning physical damage to wires</p><p>and communication in remote areas. Introducing a wireless network can</p><p>provide a solution to these issues. However, introducing wireless</p><p>communication comes with a whole new line of problems that will be</p><p>covered in this report. By utilizing the wireless communication standard</p><p>IEEE 802.11 a product can easily be integrated into an existing wired</p><p>Ethernet network (IEEE 802.3).</p><p>An introduction to the standard IEEE 802.11 and a summary of existing</p><p>products utilizing the standard for embedded systems will be given</p><p>throughout the report. This report also tries to explain key parameters for</p><p>wireless communication in an industrial environment.</p><p>This project also consists of a design and an implementation part, where the</p><p>chosen IEEE 802.11 standard will be integrated into the existing wired</p><p>Anybus-S Ethernet module from the company HMS Industrial Networks.</p><p>The integration part of the project has resulted in a working prototype called</p><p>Anybus-S Ethernet Wireless that utilizes the IEEE 802.11b/g standard for</p><p>transferring data.</p><p>The project has been really fun to participate in and it has been successful in</p><p>the terms that a working prototype exists, and the authors have gained the</p><p>knowledge in the subject as intended.</p>
5

Gestion du Cycle de Vie des Produits: Définitions, Problèmes Ouverts et Modèles de Référence

Terzi, Sergio 27 May 2005 (has links) (PDF)
Nos travaux de thèse contribuent au domaine de la Gestion du Cycle de Vie des Produits (PLM : Product Lifecycle Management) selon deux objectifs : l'un concerne plus particulièrement l'analyse et l'état de l'art des concepts liés au domaine du PLM alors que le second va chercher à tirer avantage de ces concepts pour la formalisation d'un metamodèle adapté à la Traçabilité des produits tout au long de leur cycle de vie.<br />La gestion intégrée de toute information relative au produit et à sa production est une des questions majeure de l'industrie. Une des réponses à cette question, actuellement d'actualité, concerne un paradigme naissant, défini par le vocable de Gestion du Cycle de Vie des Produits (PLM : Product Life Cycle Management). Dans ce contexte, l'une des problématiques concerne la traçabilité des produits tout au long de leur cycle de vie qui induit ainsi une nécessaire interopérabilité de l'information ainsi que des efforts de standardisation. Afin d'assurer ces échanges d'information, notre contribution, basés sur la situation actuelle des systèmes d'information d'entreprise (qui manipulent l'information sur les produits), doit aboutir à la définition d'une vue holonique d'un modèle conceptuel orienté produit d'un système de production, formalisant la structure du système d'information associé aux données de traçabilité des produits.
6

Trådlös kommunikation för Anybus

Heigren, Robert, Otterdahl, Björn January 2007 (has links)
The industry struggles with problems concerning physical damage to wires and communication in remote areas. Introducing a wireless network can provide a solution to these issues. However, introducing wireless communication comes with a whole new line of problems that will be covered in this report. By utilizing the wireless communication standard IEEE 802.11 a product can easily be integrated into an existing wired Ethernet network (IEEE 802.3). An introduction to the standard IEEE 802.11 and a summary of existing products utilizing the standard for embedded systems will be given throughout the report. This report also tries to explain key parameters for wireless communication in an industrial environment. This project also consists of a design and an implementation part, where the chosen IEEE 802.11 standard will be integrated into the existing wired Anybus-S Ethernet module from the company HMS Industrial Networks. The integration part of the project has resulted in a working prototype called Anybus-S Ethernet Wireless that utilizes the IEEE 802.11b/g standard for transferring data. The project has been really fun to participate in and it has been successful in the terms that a working prototype exists, and the authors have gained the knowledge in the subject as intended.
7

A Conceptual Design of a Reliable Hard Docking System : Docking of an utonomous underwater vehicle to the new generation A26 submarine / En konceptuell design av ett pålitligt hårddockningssystem

EKSTRÖM, ELIN, SEVERINSSON, ELLEN January 2021 (has links)
In year 2024 and 2025 the Royal Swedish Navy is expected to launch two new submarines with new possibilities to dock underwater vehicles. The submarines are part of the new Blekinge Class (A26) and will aid the Swedish Armed Forces and the Swedish Defense Materiel Administration (FMV) in their aim to develop and use more autonomous systems, to increase staff efficiency and to face the technological challenges of tomorrow. This thesis was carried out at FMV, with the purpose of investigating the physical requirements put on the new submarines, when docking an autonomous underwater vehicle. These requirements were identified through an analysis of qualitative and quantitative research. The analysis resulted in ten key insights, which led to thirteen requirements. The requirements were combined with project specific data of the AUV62 system and A26 submarine, to develop three conceptual designs of hard docking systems. The concepts were verified through analysis of material, stress and deflection, and geometric constraints. The concepts were evaluated based on how well they were fulfilling each requirement. A hammock-alike concept was shown to have most potential in being the most reliable hard docking system. The thesis ended with concluding that its purpose had been fulfilled, followed with recommendations for continued work. / Under 2024 och 2025 förväntas Svenska Marinen sjösätta två nya ubåtar, med nya förmågor gällande dockning av undervattensfordon. Ubåtarna ingår i nya Blekingeklass (A26) och är en del av Försvarsmaktens och Försvarets Materielverks (FMV) målsättning om att utveckla och använda mer autonoma system, för att öka personaleffektivitet och för att kunna möta morgondagens tekniska utmaningar. Detta examensarbete utfördes på uppdrag av FMV, med syftet att undersöka vilka fysiska krav som ställs för att hårddocka ett autonomt undervattensfordon på de nya ubåtarna. Dessa krav identifierades genom analys av en kvalitativ och kvantitativ undersökning. Analysen uppdagade tio nyckelinsikter som gav upphov till tretton krav. Kraven kombinerades med projektspecifik data för AUV62-systemet och ubåt A26, för att utveckla tre konceptuella designförslag av hårddockningssystem. Koncepten verifierades genom analys gällande material, spänning och utböjning, samt geometriska begränsningar. Koncepten utvärderades baserat på hur väl de uppfyllde respektive krav. Ett hängmatteformat koncept visade sig ha störst potential för att bli ett pålitligt hårddockningssystem. Examensarbetet avslutades med att projektets syfte ansågs vara uppfyllt, följt av förslag på vidare arbete.
8

Avaliação da Vulnerabilidade de Barramentos ao Rompimento de pequenos barramentos localizados a montante / Assessing the vulnerability of dams to the breaking of small reservoirs located upstream

MENDES, Thiago Augusto 22 August 2008 (has links)
Made available in DSpace on 2014-07-29T15:01:53Z (GMT). No. of bitstreams: 1 Dissertacao Thiago Augusto Mendes.pdf: 1579754 bytes, checksum: 97b3cf99f922e3e8f0387617e13d2db4 (MD5) Previous issue date: 2008-08-22 / In spite of Brazil being the country with one of the largest quantities of dams on the planet, there is no study that confront the influence of small dams collapse on major dams. This is very important from a strategic and planning point of view, since much of the energy produced in the country comes from hydroelectric installed in rivers. Althought the hydroelectric sizing is done following strict security techniques, the upstream reservoirs, in most cases are not. This factor leads to great uncertainty about safety of these dams. Thus, this work is important to the development of a methodology able to quantify how small dams affect the safety of large dams. The purpose was set a vulnerability rate to disruption of these small dams, thereby providing data for municipal, state and federal entities about the real situation for granting, construction and operation of dams. The determination of vulnerability rate was made with simulations conducted in the HEC-HMS hydrological model, thereby determining the additional flow from the disruption of dams along the upstream of the dam under study. The study site chosed was the basin of the Meia Ponte river - GO, precisely the Rochedo s hydroelectric, where 30 reservoirs were evaluated for disruption. It was found that the flow that reaches the Rochedo s reservoir, without considering the disruption of reservoirs located upstream (1.222 m³/s) for a return period of 10,000 years is about 31% higher than the flow planned for Rochedo, that is 935 m³/s, as informed by the Energy Company of Goiás (CELG, 2008). The calculated vulnerability rate was 1,31 for a return period of 10,000 years without considering the disruption of the upstream reservoirs and were suitable for a reservoir that was built in the 50's. However the flow that reaches the Rochedo s reservoir, considering the disruption of the upstream reservoirs for a return period of 10,000 years (1.880 m3/s) is much higher than flow considered without disruption of the upstream reservoirs. The calculated vulnerability rate goes to 1,54 for a return period of 10,000 years, wich is considered a high value that deserves care assessment / Apesar do Brasil ser o país com uma das maiores quantidades de barramentos do planeta, não existe um estudo que seja de conhecimento desse autor, que confronte a influência do colapso dos pequenos barramentos sobre grandes represas. Este aspecto é muito importante do ponto de vista estratégico e de planejamento, uma vez que boa parte da energia produzida no país vem das hidroelétricas instaladas em rios. Embora estas hidroelétricas tenham o seu dimensionamento feito seguindo rigorosas técnicas de segurança, os armazenamentos em reservatórios de montante, na maioria dos casos não o são. Este fator leva a uma grande incerteza quanto ao nível de segurança destas barragens. Dessa forma, este trabalho terá importância no desenvolvimento de uma metodologia capaz de quantificar o quanto as pequenas barragens afetam a segurança das grandes barragens. O objetivo foi definir um índice de vulnerabilidade ao rompimento dessas pequenas barragens, ajudando assim os órgãos municipais, estaduais e federais a constatar a real situação para outorga, construção e operação de barragens. A determinação do índice de vulnerabilidade será feita a partir de simulações realizadas com o modelo hidrológico HEC-HMS, determinando assim o acréscimo de vazão proveniente do rompimento das barragens localizadas à montante da barragem em estudo. O local de estudo escolhido foi a bacia hidrográfica do rio Meia Ponte - GO, precisamente a usina hidroelétrica de Rochedo, onde 30 barramentos foram avaliados para o rompimento. Verificou-se que a vazão que chega ao reservatório de Rochedo sem considerar o rompimento dos barramentos localizados à montante (1.222 m³/s) para um período de retorno de 10.000 anos é cerca de 31% maior que a vazão planejada para Rochedo, que no caso é de 935 m³/s, conforme informação fornecida pela Companhia Energética de Goiás (CELG, 2008). O índice de vulnerabilidade calculado foi de 1,31 para um período de retorno de 10.000 anos sem considerar o rompimento dos barramentos à montante, mostrando-se adequado para um reservatório que foi construído na década de 50. Já a vazão que chega ao reservatório de Rochedo, considerando o rompimento dos barramentos à montante para um tempo de retorno de 10.000 anos (1.880 m3/s) é muito superior à vazão considerada sem o rompimento dos barramentos à montante. O índice de vulnerabilidade calculado passa a ser de 1,54, para um período de retorno de 10.000 anos, considerado um valor alto merecendo cuidados de avaliação.
9

Coupled Surface Water-Groundwater Model to Analyze Sustainability of the Atascadero Subbasin

Klinchuch, Matthew Timothy 01 June 2012 (has links)
The Atascadero Subbasin, located on the central coast of California, is a small, hydraulically separated sub-region of the Paso Robles Groundwater Basin. Three local cities operate approximately 40 wells to pump the Subbasin for their entire water supply needs. Past studies have questioned sustainability of the Subbasin as the combined pumping rate by the three cities is nearing the perennial yield of the Subbasin. The studies have been inconclusive as some areas of the Subbasin have seen increases in water table elevation thus questioning the assessment that consumption is nearing perennial yield. The objective of this research was to perform a water balance study for the aquifer and examine sustainability of the Subbasin. Surface water and groundwater models were developed to investigate the interaction between the Salinas River Alluvium Soils and the deeper Paso Robles Formation based on pumping from different shallow and deep wells. Surface water hydrology of the Subbasin was studied using HEC-HMS, and Visual MODFLOW was used to model the aquifer. Both HEC-HMS and Visual MODFLOW was calibrated to improve simulation accuracy. HEC-HMS was used to quantify natural recharge to the aquifer and to simulate streamflow and water level for the Salinas River. HEC-GeoHMS was used to delineate the watershed, create sub-watersheds and channel networks, and to extract sub-watershed inputs that were used to build HEC-HMS from geospatial data including land use, soil and topography data. Different hydrogeologic layers were defined to represent the alluvium and deeper soils. Results show that currently the Atascadero Subbasin does not appear to be in overdraft as shallow groundwater wells pump Salinas River underflow and the alluvium appears to be providing some recharge to the deeper aquifer. These findings would provide municipal and water managers better understanding of where their water comes from, the effects of their pumping, and could help with developing sustainable management strategies for the Subbasin.
10

Estimating Upper Red Butte Watershed Contribution to Salt Lake Valley Water Resources

Limbu, Sal Bir 01 May 2019 (has links)
Water is crucial for domestic, agricultural, industrial, environmental, and hydropower uses. Once precipitation occurs, it eventually partitions into streamflow, evapotranspiration (ET), and groundwater recharge. Distribution of precipitation into these partitions is called a hydrologic budget. The hydrologic budget of any geographic area or watershed under different climate change conditions help water managers to make appropriate water management plans. Computer based hydrologic modeling software has been used extensively to solve many water resources problems including hydrologic budgets. Hydrologic modeling requires high quality weather parameter data. This study projected surface and groundwater flows from the portion of RBC watershed that lies above Red Butte Reservoir (RBR) to Salt Lake Valley (SLV) for water years (WYs) 2051-2060 in two climatic Representative Concentration Pathways (RCPs) scenarios, RCP 4.5 and RCP 8.5. RCP 8.5 corresponds to the pathways with higher greenhouse gas emission than RCP 4.5. To project flows, we first used Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) 4.3 model to calibrate and validate the observed streamflow for WYs 2016 and 2017 respectively. However, within RBC study area weather stations, all three weather parameters (Precipitation (P), Temperature (T), and Net Radiation (NR)) required for HEC-HMS model were missing on the same day for some periods of WYs 2016-2017. This necessitated to fill the missing parameters prior to the model calibration and validation. We hypothesized that systematically using ANN and SMs would enable making accurate estimates, even when multiple parameter values are missing on the same day. The hypothesis-estimated the missing weather parameters (P, T, and NR) values are useful for hydrologic modeling in a watershed. We ran the HEC-HMS validated model for WY 2051-2060 once for each RCP scenario, and quantified the flows to SLV. The model results showed that average stream and groundwater flows of WYs 2016 and 2017 were 14.1% and 55.7% of total study area precipitation, respectively. In the future 2051- 2060, compared with average annual surface and groundwater flows of WYs 2016-2017, percent changes in flows, respectively, were i) decreases of 29.6% and 24.2% for RCP 4.5 and ii) decreases of 26% and 23.9 % for RCP 8.5.

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