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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

Entwicklung von Strahlfängern für maximale Elektronenenergie am Beschleuniger ELBE

Pröhl, Dieter, Naumann, Bärbel, Neubert, Waldemar 31 March 2010 (has links) (PDF)
A design study of beam dumps is presented for the 40 MeV superconducting Electron-Linearaccelerator ELBE. Nuclear physical and thermal properties of selected materials are considered. Energy deposition and neutron production were calculated for a special design of the beam dump. For those Monte-Carlo simulations the particle transport rogram packages GEANT, MCNP and FLUKA have been used. The expected activation under beam conditions was estimated for selected dump materials.
2

Entwicklung von Strahlfängern für maximale Elektronenenergie am Beschleuniger ELBE

Pröhl, Dieter, Naumann, Bärbel, Neubert, Waldemar January 1999 (has links)
A design study of beam dumps is presented for the 40 MeV superconducting Electron-Linearaccelerator ELBE. Nuclear physical and thermal properties of selected materials are considered. Energy deposition and neutron production were calculated for a special design of the beam dump. For those Monte-Carlo simulations the particle transport rogram packages GEANT, MCNP and FLUKA have been used. The expected activation under beam conditions was estimated for selected dump materials.
3

Simulation studies of plasma wakefield acceleration

Hanahoe, Kieran January 2018 (has links)
Plasma-based accelerators offer the potential to achieve accelerating gradients orders of magnitude higher than are typical in conventional accelerators. A Plasma Accelerator Research Station has been proposed using the CLARA accelerator at Daresbury Laboratory. In this thesis, theory and the results of particle-in-cell simulations are presented investigating experiments that could be conducted using CLARA as well as the preceding VELA and CLARA Front End. Plasma wakefield acceleration was found to be viable with both CLARA and CLARA Front End, with accelerating gradients of GV/m and 100 MV/m scale respectively. Drive-witness and tailored bunch structures based on the CLARA bunch were also investigated. Plasma focus- ing of the VELA and CLARA Front End bunches was studied in simulations, showing that substantial focusing gradient could be achieved using a passive plasma lens. A plasma beam dump scheme using varying plasma density is also presented. This scheme allows the performance of a passive plasma beam dump to be maintained as the bunch is decelerated and has some advantages over a previously proposed method.
4

Charm production and prompt neutrino fluxes in beam dump and collider experiments

Bai, Weidong 01 May 2018 (has links)
This dissertation deals with the neutrino fluxes that come from charm decays in hadronic collisions in beam dump and collider experiments. The specific focus is on the beam dump experiment SHiP (Search for Hidden Particles) and the collider experiment LHC (Large Hadron Collider). Based on the HVQMNRPHO computer program, the next-to-leading order (NLO) perturbative QCD (pQCD) calculation is performed for charm quark. Two nonperturbative effects, the initial transverse momentum and fragmentation are modeled by a Gaussian function and the Peterson fragmentation function, respectively. The parameters in these two models are determined by comparisons with the experimental data. The distributions of charm hadrons $D_s^-$, $D^-$, $D^0$ and $\Lambda_c^-$ are thus obtained. By considering the full 3-Dimensional kinematics of the charm hadron decays in the hadron rest frame and then Lorentz transforming to the lab frame, the tau neutrino and muon neutrino fluxes are obtained. The number of neutrino charged current (CC) events at the neutrino detector are evaluated for SHiP and the LHC. The NLO pQCD evaluation predicts about 300 tau neutrino and antineutrino events for SHiP which is much higher than the number of tau neutrino events observed already at OPERA (Oscillation Project with Emulsion-tRacking Apparatus) and DONuT (Direct observation of the nu tau), and thus provides the potential to study the tau neutrino interactions with high statistics. An estimate of the possible intrinsic charm production has been performed for SHiP which may make its presence in the hadron and neutrino specta. Hundreds of tau neutrino and antineutrino events per year per kilogram of lead are achievable for a very far-forward neutrino detector at the LHC.
5

MICROCOMPUTER BASED AUTOMATIC TRUCK DISPATCHING - SYSTEM MODELING AND SIMULATION (MINING, SOFTWARE, ALGORITHM, OPEN-PIT)

Kolb, William Edward, 1960- January 1986 (has links)
No description available.
6

Methodology for a dump design optimization in large-scale open pit mines

Puell Ortiz, Jorge 05 October 2017 (has links)
Modern large-scale open pit mines move hundreds of thousands of tonnes of material daily, from the loading sources to the destination zones, whether these are massive mine dumps or, to a lesser extent, to the grinding mills. Mine dumps can be classified as leach or waste dumps, depending upon their economic viability to be processed in-place, a condition that has experienced great progress in the last decades and has reconfigured the open pit haulage network with an increase in the number of dumps. Therefore, new methods for dump design optimization are of the highest priority in mine planning management. This paper presents a methodology to model and optimize the design of a dump by minimizing the total haulage costs. The location and design of these dumps will be given mainly by the geological characteristics of the mineral, tonnage delivered, topographical conditions, infrastructure capital and transportation costs. Spatial and physical design possibilities, in addition, provide a set of parameters of mathematical and economic relationship that creates opportunities for modelling and thus facilitates the measurement and optimization of ultimate dump designs. The proposed methodology consists of: (1) Formulation of a dump model based on a system of equations relying on multiple relevant parameters; (2) Solves by minimizing the total cost using linear programming and determines a "preliminary" dump design; (3) Through a series of iterations, changes the "preliminary" footprint by projecting it to the topography and creates the ultimate dump design. Finally, an application for a waste rock dump illustrates this methodology.
7

AVALIAÇÃO DOS TEORES DE METAIS POTENCIALMENTE TÓXICOS NA MICROBACIA DO RIACHO BARRA GRANDE LOCALIZADA NO ENTORNO DO LIXÃO MUNICIPAL DA CIDADE DE IMPERATRIZ - MA.

Gama, Jullys Allan Guimarães 01 August 2013 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-08-17T14:44:32Z No. of bitstreams: 1 JULLYS ALLAN GUIMARAES GAMA.pdf: 1826371 bytes, checksum: 230f55a43f1d2ce1894678ed5b77b28c (MD5) / Made available in DSpace on 2016-08-17T14:44:32Z (GMT). No. of bitstreams: 1 JULLYS ALLAN GUIMARAES GAMA.pdf: 1826371 bytes, checksum: 230f55a43f1d2ce1894678ed5b77b28c (MD5) Previous issue date: 2013-08-01 / In the State of Maranhão, only three of the 217 municipalities have dump, the rest being made available only “dumpsters" as units of final disposal of solid waste. The municipality of Imperatriz-MA shares this reality, therefore, is for the municipal dump, which are sent every day all waste produced by the city, without any apparent worry or treatment. Starting this context, this study aimed to analyze the levels of potentially toxic metals, in the creek Barra Grande Watershed, a foremost tributary of the Tocantins River, located around the municipal dump, to evaluate the influence of the pollution effect of leach ate. Therefore, the methodology used was the type quantitative, exploratory and descriptive in nature. The main results showed that the leach ate currently generated is in methanogenic phase (ph = 8.3) and after infiltration and leaching processes, has contaminated streams and springs that are under its influence, and in view of the high concentration of Cu, Cr, Cd, Pb and Fe found in soil Cu and Cd and sediment chain Watershed. / No Estado do Maranhão, apenas três, dos 217 municípios, possuem aterro sanitário, sendo ao restante, disponibilizados apenas “lixões” como unidades de disposição final de resíduos sólidos. O município de Imperatriz-MA compartilha desta realidade, pois, é para o lixão municipal, que todos os dias são encaminhados todos os resíduos produzidos pela cidade, sem qualquer preocupação ou tratamento aparente. Partindo deste contexto, esta pesquisa teve por objetivo, analisar os teores de metais potencialmente tóxicos, na Microbacia do riacho Barra Grande, importante afluente do rio Tocantins, localizada no entorno do lixão municipal, visando avaliar a influência do efeito poluidor do chorume. Para tanto, a metodologia empregada foi do tipo quantitativa, exploratória e de natureza descritiva. Os principais resultados apontaram que, o chorume, atualmente, gerado, encontra-se em fase metanogênica (ph = 8,3) e que, após processos de infiltração e lixiviação, tem contaminado os córregos e nascentes que se encontram sob sua influência, tendo em vista os altos teores de Cu, Cr, Cd e Pb encontrados em água e em solo, e Cu e Cd, no sedimento corrente da Microbacia.
8

Análisis de la funcionalidad y desempeño de la operación semiautónoma en equipos de carga; acarreo y descarga en minería subterránea Load Haul-Dump Vehicle (LHD)

Uribe Neira, Pablo Alberto January 2014 (has links)
Tesis para optar al grado de Magíster en Gestión y Dirección de Empresas / Actualmente existen importantes desafíos en minería, no solo por las cifras de inversión estimadas, sino también por necesidad de incorporar nuevas tecnologías, generadas en base a los desafíos planteados por el aumento de costos. Los principales nuevos desafíos son derivados de las características de la roca primaria, la baja en la ley de mineral, los requerimientos de sustentabilidad y la mayor preocupación por mejorar los estándares de seguridad y salud ocupacional de los operadores. Para el futuro se requieren procesos altamente automatizados, equipamientos autónomos y operaciones telecomandadas, gestionadas fuera de las minas en busca de la continuidad operacional. Tratar de mantener los costos bajos y mejorar la productividad es el gran desafío que presenta la Minería Subterránea. En esta tesis se analizará el estado del arte de la tecnología de equipos LHD semiautónomos, sus limitaciones, las lecciones aprendidas, así como los sistemas y metodologías de navegación existentes asociados con el automatizado subterráneo en la carga, transporte y descarga, además de los resultados obtenidos en la División el Teniente. La implementación de esta tecnología en División el Teniente nació como solución a los problemas de seguridad y calidad de vida de los trabajadores, así como también para contar con un equipo robusto capaz de enfrentar las exigencias que demanda el mineral primario a ser extraído, una de las ventajas que se espera obtener como resultado, es un mayor tiempo de operación en comparación con los equipos manuales. El análisis se basará en la utilización de equipos LHD (cargadores de bajo perfil para la tarea de extracción de mineral, que consiste en cargar, transportar y descargar la roca mineralizada), los cuales cuentan con la tecnología que les permite operar en una condición semi-automática, es decir sin operador a bordo, controlados a distancia por operadores ubicados al exterior de la mina en una la sala de control distante kilómetros del área productiva. La tecnología ha demostrado ser factible de aplicar, sin embargo, se han detectado brechas en el desempeño y funcionalidades respecto de los requerimientos planteados para la División El Teniente en su Proyecto Estructural Nuevo Nivel Mina, por lo cual se requiere incorporar nuevos desarrollos tecnológicos a través de un programa de innovaciones incrementales de la tecnología de automatización de LHD, bajo un Modelo de Negocio ad-hoc y efectuar un cambio significativo de las estrategias y tácticas operacionales, mantenimiento, planificación, control centralizado, diseños mineros, entre las más relevantes, para así optimizar y capturar el mayor valor del uso de los equipos LHD semi-autónomos. El gran desafío que hoy nos impone la minería, de expandir la capacidad de producción para satisfacer las futuras demandas de los minerales, está requiriendo con urgencia de un mayor desarrollo y apoyo de las tecnologías de automatización en la minería. La dimensión de los proyectos permite generar cambios tecnológicos en pos de encontrar herramientas y sistemas que garanticen en mayor medida la calidad, eficiencia y control de las operaciones mineras. Es ahí donde está el desafío: identificar, adaptar, prepararse e implementar estas tecnologías.
9

Automated Live Acquisition of Volatile Data : Through the use of a programmable HID control chip

Berggren, Tommy, Denham-Smith, Adam January 2013 (has links)
This research lays a foundation for automated acquisition of volatile data by presenting a prototype device which carries out the deeds of a forensic investigator, essentially making it a “forensic investigator on a stick”. The Teensy 3.0 device is programmed to interact with an external USB device for storage purposes. All interaction with a live target system must be documented thoroughly according to forensic best practices. Therefore quantitative measurements of system contamination related to the device actions are presented. The device is conclusively able to perform a memory dump and provide a warning of the existence of Truecrypt encrypted containers.
10

PSQS – Power Supply Quality Simulator

Ahlström, Johan, Nordström, Edward January 2008 (has links)
Kitron had wishes to be able to test and measure how disturbance affects their vehicle electronic units before they have been verified by SP Technical Research Institute of Sweden in Borås. This work started with the writing of a demand specification together with Kitron for a product PSQS, Power Supply Quality Simulator, which can generate some test pulses according to a standard for electronic units to Volvos vehicles. A design proposal was developed with the help the demand specification and was verified with the help of simulations. All electric schematics was designed with the guide of the design proposal. The pulses realized in the works of this thesis are those which Kitron experienced that they have a need to test in their own premises and which are possible to generate with the means available. All work took place at Kitron in Jönköping, the restriction of the work has been the cost of components not to be to high as well as the finished product shall be easily managed. This thesis work resulted in a unit which is possible to produce a number of disturbances on the voltage feed to a unit under test. Some pulses have not been completely correct according to Volvos standard. There are large possibilities to further develop PSQS to a unit that follows Volvos standard and even other vehicle producer’s standards.

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