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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

Characterization of the MEMS directional sound sensor fabricated using the SOIMUMPs process

Dritsas, Antonios. January 2008 (has links) (PDF)
Thesis (M.S. in Applied Physics and M.S. in Operations Research)--Naval Postgraduate School, June 2008. / Thesis Advisor(s): Karunasiri, Gamani ; Koyak, Robert. "June 2008." Description based on title screen as viewed on August 25, 2008. Includes bibliographical references (p. 89-90). Also available in print.
2

Link-layer and network-layer performance of an undersea acoustic network at Fleet Battle Experiment-India

Hartfield, Grant I. 06 1900 (has links)
Approved for public release, distribution is unlimited / This thesis is an analysis of the link-layer and network-layer performance of an experimental Seaweb undersea acoustic network. The objective is to statistically determine RTS/CTS handshaking and ARQ retransmission performance during the Fleet Battle Experiment-India, executed in June 2001. Many factors constrain or impair undersea acoustic communications. Analysis of a sample portion of the data reveals insights about the overall throughput, latency, and reliability of the Seaweb network. / Lieutenant, United States Navy
3

An instrument system to measure turbulence from an underwater habitat. --

Tiffin, Scott. January 1974 (has links)
Thesis (M.Eng.) -- Memorial University of Newfoundland. 1974. / Typescript. Bibliography : leaves 86-90. Also available online.
4

System Design of Undersea Vehicles with Multiple Sources of Uncertainty

Benanzer, Todd W. 31 July 2008 (has links)
No description available.
5

TELEMETRY IN TESTING OF UNDERSEAS WEAPONS

Hull, Roy T., Jr. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The performance testing of underseas weapons involves many of the same challenges as for other “smart” systems. Data sets on the order of GigaBytes must be extracted, processed, analyzed, and stored. A few KiloBytes of significant information must be efficiently identified and accessed for analysis out of the great mass of data. Data from various sources must be time correlated and fused together to allow full analysis of the complex interactions which lead to a given test result. The fact that the various sources all use different formats and medias just adds to the fun. Testing of underseas weapons also involves some unique problems. Since real time data transmission is not practical; the vast bulk of the test data is recorded and then recovered with the vehicle at the end of the test. Acoustics are relied on for identification and ranging. As systems continue to get smarter; the rates, capacities, and “smarts” of the equipment and software used to process test data must similarly increase. The NUWES telemetry capabilities developed to test and analyze underseas weapons could be of use on other government related projects. “Key words: Telemetry, data processing, data analysis, undersea weapons, smart weapons, torpedoes, performance testing.”
6

Planejamento de operações de manutenção submarina. / Planning problem of offshore maintenance.

Aradi, Thabiani Cristine 12 January 2015 (has links)
A presente pesquisa buscou resolver o problema de planejamento de operações submarinas através das perspectivas de programação de tarefas e dimensionamento de frota. O problema consistiu em estabelecer a melhor sequência de tarefas a serem atendidas por embarcações levando em consideração sua compatibilidade, regras de sequenciamento e o tamanho da frota. O problema é uma extensão do modelo clássico de roteirização com janelas de tempo com o objetivo de minimizar os custos associados à roteirização e as perdas econômicas associadas às interrupções de produção. A resolução do trabalho concentrou-se no curto e longo prazo, utilizando como principal método de solução a heurística Simulated Anneling por meio de um algoritmo de simulação-otimização. / This research aimed at solving the problem of planning underwater operations that involves job scheduling and fleet sizing decisions. The problem consisted in establish the best sequence of tasks to be atended by vessels taking into account compatibility constraints, sequencing rules and the size of the fleet. The problem is an extension of the classical vehicle routing problem with time windows. The objective is to minimize the routing costs and the economic losses associated with production losses. The solution procedure focused on short and long-term decisions based on the heuristic Simulated Anneling through a simulation-optimization algorithm.
7

Planejamento de operações de manutenção submarina. / Planning problem of offshore maintenance.

Thabiani Cristine Aradi 12 January 2015 (has links)
A presente pesquisa buscou resolver o problema de planejamento de operações submarinas através das perspectivas de programação de tarefas e dimensionamento de frota. O problema consistiu em estabelecer a melhor sequência de tarefas a serem atendidas por embarcações levando em consideração sua compatibilidade, regras de sequenciamento e o tamanho da frota. O problema é uma extensão do modelo clássico de roteirização com janelas de tempo com o objetivo de minimizar os custos associados à roteirização e as perdas econômicas associadas às interrupções de produção. A resolução do trabalho concentrou-se no curto e longo prazo, utilizando como principal método de solução a heurística Simulated Anneling por meio de um algoritmo de simulação-otimização. / This research aimed at solving the problem of planning underwater operations that involves job scheduling and fleet sizing decisions. The problem consisted in establish the best sequence of tasks to be atended by vessels taking into account compatibility constraints, sequencing rules and the size of the fleet. The problem is an extension of the classical vehicle routing problem with time windows. The objective is to minimize the routing costs and the economic losses associated with production losses. The solution procedure focused on short and long-term decisions based on the heuristic Simulated Anneling through a simulation-optimization algorithm.
8

Mineração oceânica: uma alternativa sustentável para o aproveitamento de areias quartzosas. / Ocean mining: a sustainable alternative to the use of quartz sands.

Rocha, Luciano 06 November 2015 (has links)
Este estudo apresenta ao Departamento de Engenharia de Minas e Petróleo (PMI) da Escola Politécnica da USP, e também a toda a sociedade, a importância que os oceanos têm com relação às suas riquezas minerais. Pretende ainda mostrar a grande responsabilidade que um empreendimento mineiro no fundo do mar precisa ter, com relação aos impactos ambientais, sendo possível minerar em regiões profundas no oceano promovendo a sustentabilidade. A ideia da mineração oceânica/submarina está ainda sendo amadurecida, este é o momento adequado para se propor metodologias de trabalho submarino sustentáveis; mitigar seus impactos. Este trabalho abrange o tema de maneira ampla, abordando o aspecto histórico, legal, ambiental, bem como questões técnicas de engenharia de minas, como sondagem submarina, caracterização tecnológica, lavra submarina, beneficiamento de minério oceânico e descarte de rejeitos. O trabalho apresenta os passos e resultados de um caso real de exploração oceânica. Trata-se de um estudo para viabilizar economicamente a extração e o beneficiamento de areia marinha, para fins industriais, proveniente da Baía de Guanabara (RJ). O trabalho apresenta desde o planejamento da amostragem no fundo do mar, execução destes trabalhos, caracterização tecnológica, simulação de processo e estudos específicos do uso industrial da areia após beneficiamento. Apresenta ainda uma proposta de rota de processo para a areia marinha e questões ligadas à lavra e ao descarte de rejeitos. / This study aims to show the importance of the oceans and its mineral wealth. It intends also to show the big responsibility that an undersea enterprise must bear concerning the environmental impact. It shows the availability to minein a sustainable way in the bottom of the sea. The undersea mining is still raising, now is the auspicious time to suggest sustainably submarine work methodologies; to mitigate its impact. This study covers the historic, legal and environmental aspects, as well as technical issues of mining engineering such as undersea survey, process mineralogy, undersea mining, mineral beneficiation for marine ores and tailings disposal. This study presents the steps and results of a real subsea exploration case. The studied ore is a marine sand from Baía de Guanabara (Rio de Janeiro), aiming to supply industrial market. This is a feasibility and technical study to show how to exploit and process this kind of ore. The study shows the undersea survey planning and its execution, the process mineralogy planning and its results, process simulation and some specific studies to industrial uses for this sand, after its beneficiation. Besides these subjects, the study proposes an industrial process route for process and tailings disposal.
9

Mineração oceânica: uma alternativa sustentável para o aproveitamento de areias quartzosas. / Ocean mining: a sustainable alternative to the use of quartz sands.

Luciano Rocha 06 November 2015 (has links)
Este estudo apresenta ao Departamento de Engenharia de Minas e Petróleo (PMI) da Escola Politécnica da USP, e também a toda a sociedade, a importância que os oceanos têm com relação às suas riquezas minerais. Pretende ainda mostrar a grande responsabilidade que um empreendimento mineiro no fundo do mar precisa ter, com relação aos impactos ambientais, sendo possível minerar em regiões profundas no oceano promovendo a sustentabilidade. A ideia da mineração oceânica/submarina está ainda sendo amadurecida, este é o momento adequado para se propor metodologias de trabalho submarino sustentáveis; mitigar seus impactos. Este trabalho abrange o tema de maneira ampla, abordando o aspecto histórico, legal, ambiental, bem como questões técnicas de engenharia de minas, como sondagem submarina, caracterização tecnológica, lavra submarina, beneficiamento de minério oceânico e descarte de rejeitos. O trabalho apresenta os passos e resultados de um caso real de exploração oceânica. Trata-se de um estudo para viabilizar economicamente a extração e o beneficiamento de areia marinha, para fins industriais, proveniente da Baía de Guanabara (RJ). O trabalho apresenta desde o planejamento da amostragem no fundo do mar, execução destes trabalhos, caracterização tecnológica, simulação de processo e estudos específicos do uso industrial da areia após beneficiamento. Apresenta ainda uma proposta de rota de processo para a areia marinha e questões ligadas à lavra e ao descarte de rejeitos. / This study aims to show the importance of the oceans and its mineral wealth. It intends also to show the big responsibility that an undersea enterprise must bear concerning the environmental impact. It shows the availability to minein a sustainable way in the bottom of the sea. The undersea mining is still raising, now is the auspicious time to suggest sustainably submarine work methodologies; to mitigate its impact. This study covers the historic, legal and environmental aspects, as well as technical issues of mining engineering such as undersea survey, process mineralogy, undersea mining, mineral beneficiation for marine ores and tailings disposal. This study presents the steps and results of a real subsea exploration case. The studied ore is a marine sand from Baía de Guanabara (Rio de Janeiro), aiming to supply industrial market. This is a feasibility and technical study to show how to exploit and process this kind of ore. The study shows the undersea survey planning and its execution, the process mineralogy planning and its results, process simulation and some specific studies to industrial uses for this sand, after its beneficiation. Besides these subjects, the study proposes an industrial process route for process and tailings disposal.
10

TRANSPORT MARITIME DE PRODUITS CHIMIQUES LIQUIDES ET FLOTTANTS : ETUDE EXPERIMENTALE DU REJET ACCIDENTEL SOUS-MARIN SUITE A UN NAUFRAGE / MARITIME TRANSPORT OF LIQUID AND FLOATING CHEMICALS : EXPERIMENTAL STUDY OF THE SUBMARINE ACCIDENTAL RELEASE FOLLOWING A SHIPWRECK

Fuhrer, Mélanie 18 December 2012 (has links)
Le transport par voie maritime s’est développé très rapidement durant la dernière décennie. Il constitue la solution idéale pour déplacer à faibles coûts d’importantes quantités de marchandises sur de longues distances. L’accroissement de ces échanges entraine inévitablement une augmentation de la fréquentation des routes maritimes, de la densité du trafic et donc du risque d’accident et de naufrage.Les quantités impliquées lors d’un accident étant importantes, un rejet sous-marin de produit chimique issu d’une épave peut provoquer de graves conséquences environnementales et humaines. Or, les mécanismes physico-chimiques apparaissant lors du transfert du produit à la surface sont encore mal compris. Ces mécanismes dépendent de nombreux paramètres dont les propriétés physico-chimiques intrinsèques au produit et celles propres à l’environnement de l’accident.Ce travail de recherche, réalisé en collaboration entre l’Ecole des Mines d’Alès et le Cedre, s’inscrit dans l’amélioration de la compréhension du comportement d’un rejet de produit chimique liquide, flottant et soluble issu d’une épave. Cette étude expérimentale a été réalisée selon 3 points :- La phénoménologie du rejet à la brèche dont l’objectif est de quantifier le débit et les modes de rejet,- Le comportement hydrodynamique du produit libéré et son évolution lors de la remontée dans la colonne d’eau,- Le transfert de matière du produit lors de sa solubilisation dans la colonne d’eau.Pour chaque point, les résultats obtenus sont comparés à ceux prédits par les corrélations disponibles dans la littérature afin de proposer une modélisation globale des conséquences adaptée à la gestion des pollutions marines. / Maritime transport quickly increases during the last decade. It is the cheapest way to transport large quantities of goods over long distances. The growth of this trade necessarily leads to an increase in the traffic density and therefore the risk of accident and sinking increases as well.The large amount of chemicals involved in an accident may threaten the environment and human health in case of shipwreck with underwater chemical release. Unfortunately the physicochemical mechanisms occurring during the transfer of a chemical to the sea surface are still poorly understood. Those mechanisms depend on various parameters such as the physicochemical properties of the chemicals and the specific properties of the accident surroundings. This research was conducted in collaboration with the Ecole des Mines d'Alès and Cedre in a global approach to understand the behaviour of liquid, floating and soluble chemicals released after a shipwreck. This experimental study has been carried out according to 3 main points:- The phenomenology of a release at the breach. The objectives are to quantify the flow rate and the release pattern,- The hydrodynamic behaviour of the released chemicals and their fate in the water column,- The mass transfer of the chemical during its solubilization in the water column.For each point, the results are compared to those predicted by correlations in the literature in order to propose a global model of consequences that is adapted to the marine pollution management.

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