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Otimização das formas de cascos de deslocamento em relação a sua resistência ao avanço.; Displacement hull optimization regarding to ship wave resistance.

Alvarez, Rodrigo Loureiro Prado
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 11/02/2008 PT
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Devido à constante necessidade de construções de novas embarcações, quer seja pela demanda do mercado, quer seja pela renovação da frota, o desenvolvimento de programas computacionais que auxiliem na fase inicial de projeto torna-se bastante útil. Assim, o desenvolvimento de um procedimento de análise que permita obter formas de melhor desempenho vem a agregar valor nesta etapa de conceituação da geometria do navio. O trabalho aqui apresentado tem como objetivo discorrer sobre um método capaz de otimizar a geometria de um casco de deslocamento conhecido em relação a sua resistência ao avanço, sem perder, porém, as suas características principais, como corpo paralelo médio, por exemplo. Para tanto, dentro deste processo de otimização já estão inseridas algumas restrições que garantem a viabilidade da solução final, tais como variação máxima no comprimento, no volume total e na estabilidade do navio. A modelagem da embarcação pode ser feita através de funções B-Splines cúbicas de superfície, cujos pontos de controle (parâmetros inerentes à função) podem ser modificados de tal sorte a atingir um valor ótimo para a resistência ao avanço. Esta, por sua vez, será obtida através da soma de duas parcelas...

Avaliação das instalações de máquinas em navios visando redução do uso de combustível fóssil.; Evaluation of ship machinery instalations for reducing the use of fossil fuel.

Valle Filho, Gilberto Dória do
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/06/2011 PT
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Este trabalho trata da questão da redução de consumo de combustível fóssil em instalações de máquinas de navios. É um tema de grande interesse no momento, devido ao alto custo operacional e à emissão de poluentes decorrentes do processo da combustão desses derivados de petróleo. Apresenta-se, inicialmente o cenário atual e tendências futuras das instalações propulsoras convencionais que usam óleo pesado ou Diesel. Em seguida, são examinadas alternativas propostas para redução de consumo de combustíveis fósseis nos navios, que são enquadradas em três categorias. A primeira delas envolve possíveis melhorias de projeto para redução da demanda de energia. As outras categorias se referem ao emprego de fontes alternativas de energia, que introduzem uma força propulsora adicional, reduzindo o empuxo requerido do hélice, ou uma potência suplementar no eixo propulsor. Em ambos os casos há também uma redução de demanda de potência requerida do motor Diesel. Na seqüência, são apresentados e discutidos fundamentos termodinâmicos, com ênfase nas análises energética e exergética, como ferramentas para avaliação das máquinas dos navios. A análise exergética, diferentemente do enfoque apenas energético...

Modelagem e análise de duas alternativas para operações de transferência de petróleo entre dois navios em alto-mar.; Modeling and analysis of two alternatives for underway ship-to-ship transfer of oil in open sea.

Souza, Carlos Eduardo Silva de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/08/2012 PT
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Navios aliviadores com sistemas de posicionamento dinâmico (SPD) são dispendiosos. Dessa forma, é desejável que se otimize sua utilização, por exemplo, através da redução da quantidade de viagens entre as plataformas em alto-mar e os terminais na costa. Quando o petróleo produzido é destinado à exportação, uma solução é transferi-lo diretamente do aliviador ao navio exportador (geralmente um VLCC) através das operações conhecidas como ship-to-ship, ainda em alto-mar e próximo aos campos de produção. No entanto, uma vez que VLCCs raramente são providos de SPD, é necessário que se desenvolvam formas de se assegurar a controlabilidade de ambos os navios durante a operação de transferência. Nesse sentido, duas diferentes configurações de operações ship-to-ship são propostas. Uma delas consiste em realizar a transferência com os navios avançando lado a lado. As embarcações são amarradas e então o VLCC desenvolve potência avante, rebocando o aliviador que mantém suas máquinas ociosas. A outra solução consiste em transferir o petróleo enquanto os navios mantêm uma formação em comboio, com o VLCC seguindo uma trajetória arbitrária e sendo seguido pelo aliviador, que mantém uma distância relativa através de uma estratégia específica de piloto automático. Os modelos dinâmicos para ambas as operações são desenvolvidos e implementados em simuladores numéricos. Os resultados das simulações são discutidos e utilizados para que se avalie a viabilidade operacional das operações sob diferentes condições ambientais e de carregamento dos navios.; Shuttle tankers with dynamic positioning (DP) systems are expensive ships. Therefore...

Ship-berth link and demurrage costs: evaluating different allocation policies and queue priorities via simulation

Wanke,Peter
Fonte: Sociedade Brasileira de Pesquisa Operacional Publicador: Sociedade Brasileira de Pesquisa Operacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2011 EN
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The ship-berth link is one of the most critical aspects to be managed at port operations. Until now, simulation models have considered the impact of queue priorities, such as size and type of ships, on waiting times. This research differentiates from previous studies not only by considering another variable - the demurrage cost for each type of ship -, but also by considering the possibility of different berth allocation policies. It reports on a simulation study on small Brazilian private container terminal, where different berth allocation policies and queue priorities have been tested. Results and further analyses conducted via MANOVA indicate that the demurrage cost ratio between large and small ships and the critical waiting time in queue, after which demurrage costs are charged, impact on the choice of most adequate combination of policies and priorities. The analysis presented in this paper may help port authorities in determining a more precise figure for total demurrage costs

13.122 Ship Structural Analysis & Design, Spring 2003; Ship Structural Analysis & Design

Burke, David V.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
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Ship longitudinal strength and hull primary stresses. Ship structural design concepts. Effect of superstructures and dissimilar materials on primary strength. Transverse shear stresses in the hull girder. Torsional strength of ships.Design limit states including plate bending, column and panel buckling, panel ultimate strength, and plastic analysis. Matrix stiffness, grillage, and finite element analysis. Computer projects on the structural design of a midship module. From the course home page: Course Description This course is intended for first year graduate students and advanced undergraduates with an interest in design of ships or offshore structures. It requires a sufficient background in structural mechanics. Computer applications are utilized, with emphasis on the theory underlying the analysis. Hydrostatic loading, shear load and bending moment, and resulting primary hull primary stresses will be developed. Topics will include; ship structural design concepts, effect of superstructures and dissimilar materials on primary strength, transverse shear stresses in the hull girder, and torsional strength among others. Failure mechanisms and design limit states will be developed for plate bending, column and panel buckling, panel ultimate strength...

Summary report on the Huron and Ontario Ship Canal.

Huron and Ontario Ship Canal Company.
Fonte: Toronto : Chewett, Publicador: Toronto : Chewett,
Tipo: Artigo de Revista Científica
ENG
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Niagara Ship Canal : letter from the Secretary of War, transmitting report by Colonel Blunt, on the surveys for a ship canal to connect Lakes Erie and Ontario (1868)

Blunt, Charles E.
Fonte: Brock University Publicador: Brock University
Tipo: Livro
EN
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March 3, 1868. -- Referred to the Select Committee on the Niagara Ship Canal.

Model based ISAR ship classification

Rice, F.; Cooke, T.; Gibbins, D.
Fonte: Academic Press Inc Elsevier Science Publicador: Academic Press Inc Elsevier Science
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
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This paper describes a method for ISAR image classification, based on a comparison of range-Doppler imagery to supplied 3D ship reference models. This comparison is performed in the image domain by first estimating ship motion for each frame in a sequence of ISAR images. ISAR images are then simulated using this estimated motion applied to some known 3D reference models, and the model image and real images are compared to produce a match score for use in classification. The effect of estimation error in each of the motion parameters is also investigated.; Feng Rice, Tristrom Cooke, and Danny Gibbins

Houston Ship Channel map defining general cargo shipside terminals

Houston Ship Channel (Tex.)
Fonte: Rice University Publicador: Rice University
ENG
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Houston Ship Channel map; Houston Ship Channel Map defining general cargo shipside terminals prepared by the Navigation District Engineering Department.

Application of VAX/VMS graphics for solving preliminary ship design problems

McGowan, Gerald K.
Fonte: Monterey, California : Naval Postgraduate School Publicador: Monterey, California : Naval Postgraduate School
Tipo: Tese de Doutorado
EN_US
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Approved for public release; distribution is unlimited; The VAX/VMS UIS graphics library routines were used in the creation of a menu driven, interactive program which solves basic preliminary ship design problems. The program uses a menu with active mouse and keyboard to select options, enter data, and control program execution. At present, the program solves transverse and longitudinal static stability problems and predicts the effects of shifting weight in three planes. It also calculates the hydrodynamic derivatives for maneuvering performance and predicts the turning circle characteristics of the ship. Provisions for a hardcopy, detailed report are also included. Space has been allocated to include future program modules or user supplied programs.

Application of a robust QFT linear control method to the course changing manoeuvring of a ship

Rueda Rodríguez, Teresa M.; Velasco González, Francisco Jesús; Moyano Pérez, Emiliano; López García, Eloy; Cruz García, Jesús Manuel de la
Fonte: Sociedad Española de Estudios Cientificos Marinos (SEECMAR) Publicador: Sociedad Española de Estudios Cientificos Marinos (SEECMAR)
Tipo: info:eu-repo/semantics/article; submittedVersion
SPA; ENG
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This paper describes in detail the design methodology of a robust QFT (Quantitative Feedback Theory) controller for the control of the course changing of a ship. A linear model is used with uncertainty in the parameters. The system is designed to fulfil the specifications of robust stability and robust tracking of a reference system

“SEA SWAT” a littoral combat ship for Sea Base Defense; “Sea Archer” Distributed Aviation Platform

Echols, Robert; Santos, Wilfredo; Fernandez, Constance; Didoszak, Jarema; Cabezas, Rodrigo; Lunt, William; Kurultay, Aziz; Zafer, Elcin
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
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Approved for public release; distribution in unlimited.; Unlike past conflicts which were characterized by major naval battles in the open ocean, present day threats are mostly associated with rogue nations and terrorist cells. These threats are of a different nature to past threats and may strike at unsuspected times and locations. The United States Navy may operate from a Sea Base which projects power ashore through the use of surface and air assets. These assets must transit from the Sea Base in the blue water through the littoral region in order to reach the objective area. Total ship system designs of a group of high-speed littoral combat ships (LCS) are required which are capable of operating in these regions and defending the Sea Base and the surface and air assets from an asymmetric threat. With the modular design and the ability to carry multiple helicopters and underwater vehicles (UUV), the SEA SWAT LCS concept can be quickly employed as a force multiplier capable of operating as an Air Warfare or Undersea/Mine Warfare mission platform. With the addition of the core and Surface Warfare sensors and weapons to one of these modular mission packages, the SEA SWAT LCS concept for sea base defense will ensure air, surface and subsurface superiority during conflict. An advanced electrical power system in conjunction with an integrated propulsion system and zonal power distribution provides sustained combat capability against multiple asymmetric threats. Its enclosed super-structure allows for high survivability in a CBR environment.

A geographic optimization approach to coast guard ship basing

Gençay, Mehmet Ali
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
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Approved for public release; distribution is unlimited; This thesis studies the problem of finding efficient ship base locations, area of operations (AO) among bases, and ship assignments for a coast guard (CG) organization. This problem is faced by many CGs around the world and is motivated by the need to optimize operational outcomes in the face of budget constraints. There is a need for a tool to optimize the placement of the available number of ships to candidate bases and the assignment of the AOs for each base. In this thesis, we developed a model that takes the objective of minimizing the weighted demand for CG services. We also used constraints to have proportionate AOs to the number of ships on each base and partition constraints. To the best of our knowledge, until now, there has yet to be a tool designed for finding both ship allocations and AOs for each base. Therefore, developing this tool is a huge step forward in this area.; ; Lieutenant Junior Grade, Turkish Coast Guard

Defense of surface ships against anti ship missiles

Kumar, Ramesh
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
EN_US
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This thesis discusses the Anti-Ship Missile problem and explores the various options available for countering the Anti-Ship Missile. Special emphasis has been given to the chaff solution for defeating the Anti-Ship Missile. A program has been written to enable the testing of the effectiveness of the medium range and close range chaff deployed in conjunction with various conditions of wind and various ship's courses. The program can be used to determine the best solution for deploying the medium range chaff given the known parameters such as detection ranges and probable wind conditions. The program was run with medium range chaff deployed in the default position and the wind's course was varied through 180 degrees. For each of the courses of the wind 3 wind speeds were tried. The ship's course was also varied through 360 degrees for each of the winds courses in 45 degree steps. The seduction chaff was automatically deployed by the program; http://archive.org/details/defenseofsurface00kama; Indian Navy author.

A comparison of ship maneuvering characteristics for rudders and podded propulsors

Betancourt, Michelle K.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xii, 71 p. ;
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A comparison of a high speed container ship using a rudder versus a podded propulsor is made to study replacing a rudder with a pod. A mathematical model is altered to simulate a ship operating with a rudder and with a pod to maneuver. The model incorporates the nonlinear maneuvering equations and couples the surge and sway forces, yaw and roll moment, and the roll angle induced during a steady turn with varying rudder and pod angles. The model uses the hydrodynamic derivatives and coefficients for a high speed container ship. The equations are numerically integrated in order to predict the roll angle, sway and surge velocities, and the ship's position in the xy-plane. Both transient and steady state results are utilized to quantify the relative efficiency of each system. The results are used as a preliminary study into replacing a rudder on a ship with a podded propulsor. The results indicate that the ship responds faster and has a shorter turning radius with the pod at lower initial speeds and pod angles, while the rudder responds better at high speeds regardless of angle. Further research is necessary to study the effects of changing the pod's position and increasing the number of pods used.; US Navy (USN) author.

Analysis of amphibious ship lift capability

Williams, Eric D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: x, 89 p.
EN_US
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Approved for public release; distribution is unlimited; Amphibious ship lift is crucial in supporting operations of Marine Air Ground Task Forces (MAGTF) for a wide range of conflicts. This thesis examines three different aspects of amphibious ship lift capability. First, gross lift capabilities of all amphibious ships in the Navy today are determined. Since some storage space on board a ship is required for access, tie-downs, and other considerations, the second step of this thesis is to use historical load-out data from six-month deployments to derive expected net lift capability from gross lift capability. A three-ship Amphibious Ready Group (ARG) is traditionally required to support a six-month MAGTh deployment. 'The final part of this thesis utilizes a linear program to determine specific ship combinations that optimize ARG lift capability for both the Pacific and Atlantic Fleets.; http://www.archive.org/details/analysisofamphib00will; Lieutenant, United States Navy

A regional deterrence ship design

Calvano, Charles Natale; Alexander, Dwight Russell; Cottle, Dean J.; Kettell, Kent William.; Riedel, Jeffery Scott.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Relatório Formato: 1 v. (various pagings) : ill. ; 28 cm.
EN_US
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A systems engineering approach to the development of a warship optimized for the deterrence of regional conflicts in littoral waters is presented, followed by a description of the preliminary design of the ship shown by analysis to be most effective. The requirement for the project reported was to develop a ship which would be effective in deterring regional wars among third world nations; in hampering the military effectiveness of the aggressor should deterrence fail and in protecting or evacuating limited numbers of civilians. The study reports on an analysis of likely threat weapons, on the means used to choose defensive combat system capabilities to defeat such weapons and on the selection of capabilities necessary for successful operation in littoral waters. Major emphasis is placed on measures intended to significantly improve the ship's survivability relative to existing combatants. The design description includes data and numerous drawings. Ship design, Littoral, Regional conflict, Survivability, Warship, Combatant ship Limitation Code; Naval Sea Systems Command Ship Design & System Engineering Group; http://archive.org/details/regionaldeterren00calv; NAVAL SEA SYSTEMS COMMAND SHIP DESIGN & SYSTEMS ENGINEERING GROUP; NA

Network shortest path application for optimum track ship routing

Montes, Anel A.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 75 p. : col. ill. ;
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The United States Navy Meteorology and Oceanography (METOC) community routes ships for weather evasion using advanced meteorological modeling and satellite data, but lacks a tool to enable fewer ship routers to make better routing decisions faster. Limited resources and rising costs are impacting the frequency and duration of current naval operations. The Commander, Naval Meteorology and Oceanography Command has ordered the community to find efficiencies and automation possibilities in order to meet lower manning levels, reduce waste, and increase savings. Outside of the Navy, Ocean Systems Incorporated in Alameda, CA developed the Ship Tracking and Routing System (STARS) software package to calculate optimum sea routes based on weather model data. However, METOC ship routers are reluctant to adopt this complex software. To help solve this, we modeled Optimum Track Ship Routing (OTSR) for U.S. Navy warships using a network graph of the Western Pacific Ocean. A binary heap version of Dijkstra's algorithm determines the optimum route given model generated wind and seas input. We test the model against recent weather data to verify the model's performance, and to historical divert route recommendations in order to validate against routes developed by OTSR personnel.

Ship scheduling with time-varying draft restrictions: a case study in optimisation with time-varying costs

Kelareva, Elena
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
EN_AU
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In the last few decades, optimisation problems in maritime transportation have received increased interest from researchers, since the huge size of the maritime transportation industry means that even small improvements in efficiency carry a high potential benefit. One area of maritime transportation that has remained under-researched is the impact of draft restrictions at ports. Many ports have restrictions on ship draft (distance between the waterline and the keel) which vary over time due to variation in environmental conditions. However, existing optimisation problems in maritime transportation ignore time variation in draft restrictions, thus potentially missing out on opportunities to load more cargo at high tide when there is more water available for the ship to sail in, and more cargo can be loaded safely. This thesis introduces time-varying restrictions on ship draft into several optimisation problems in the maritime industry. First, the Bulk Port Cargo Throughput Optimisation Problem is introduced. This is a novel problem that maximises the amount of cargo carried on a set of ships sailing from a draft-restricted bulk export port. A number of approaches to solving this problem are investigated, and a commercial system - DUKC Optimiser - based on this research is discussed. The DUKC Optimiser system won the Australia-wide NASSCOM Innovation Student Award for IT-Enabled Business Innovation in 2013. The system is now in use at Port Hedland...

The Delaware Ship and Boat Building Industry, 1830-1940: An Historic Context

Doerrfeld, Dean A.; Siders (Sheppard), Rebecca J.; Herman, Bernard L.; Ames, David L.
Fonte: Universidade de Delaware Publicador: Universidade de Delaware
Formato: 14649175 bytes; application/pdf
EN_US
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This historic context develops criteria for the evaluation of the physical remains of the ship and boatbuilding industry in Delaware between 1830 and 1940 to determine their significance and potential eligibility for inclusion on the National Register of Historic Places. By examining technology, the construction process of ships and boats, and ship yard organization, this historic context will explore a segment of Delaware's industrial heritage that reached numerous cities and towns along Delaware's coastal waterways and extended well beyond the Brandywine River in the north (traditionally thought of as the industrial center of Delaware).