1,044 results on '"Ship design"'
Search Results
152. Regression analysis for container ships in the early design stage.
- Author
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Rinauro, B., Begovic, E., Mauro, F., and Rosano, G.
- Subjects
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CONTAINER ships , *REGRESSION analysis , *REGRESSION trees , *NAVAL architecture , *DATABASES , *GOODNESS-of-fit tests , *FREIGHT & freightage - Abstract
The seaway trade market has expanded in the last years and container ship dimensions are constantly increasing for higher cargo capacity. In the early design stage, main dimensions are usually determined based on an existing ship database from which regression formulas are derived. In the present paper, a database of 260 non-sister container ships built from 1979 to 2022, representing 20% of the world fleet, has been considered to derive and compare different types of regressions. Simple regressions have been developed and compared with equivalent formulations available in literature, proving better approximations of the trends. The study has been further extended by multivariable regressions and forest tree algorithms, which allow the use of more than one independent variable and provide a better fitting compared to simple regressions. Forest tree regressions return the highest values of fitting coefficients, but the technique is not of easy application due to the absence of mathematical expressions. The main contribution is the updated set of simple and multivariable regression formulas which have a higher goodness of fit than previous works and can be easily employed by designers in the early design stage and in multi-attribute design procedures. • Database of 260 non-sister container ships built from 1979 to 2022. • Covering 20% of the world container ship fleet. • Main characteristics analyzed by regressions analysis and forest trees. • Simple regression formulas compared with state-of-the-art regressions. • Improved regression formulas for early ship design. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
153. A numerical analysis on the drainage capacity of a ropax vessel in the garage deck, in still water and in waves.
- Author
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Acanfora, Maria, Pennino, Silvia, and Scamardella, Antonio
- Subjects
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WATER waves , *NUMERICAL analysis , *DRAINAGE , *FREE surfaces , *FIREFIGHTING , *CONTAINER terminals - Abstract
The ropax vessels are designed to provide the transfer of vehicles, cargo, and passengers and to ensure maximum comfort and safety. The absence of a transversal subdivision for all vessel length poses serious threats to ship safety in case of flooding of the garage deck. When the floodwater is not properly and efficiently drained overboard it can have detrimental consequences both on ship stability, due to large free surface effects and, on loads on deck structures due to the pressure of the accumulated water. In this paper, we propose and apply a fast numerical method for the study of the drainage capacity in the garage deck of a ropax vessel assuming a passive drainage system i.e. comprising only scuppers, whereas the investigated flooding scenario depends on fire fighting operations. The effectiveness of the drainage system is simulated accounting for ship dynamics in calm water and in waves, by adopting a hybrid non-linear numerical model. Flooded water is modelled by lumped mass method; the couplings between ship and floodwater dynamics is achieved by the apparent gravity technique. Two scupper configurations are considered, by modifying scupper dimensions and positions on board. Several numerical simulations are carried out assuming also partially inefficient scuppers. The analysis of the obtained results can provide a general support for the design of passive drainage systems. Based on the outcomes of the case study, this research discloses an improvement in the drainage system when more scuppers are allocated at the stern zone. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
154. Emission Abatement Technology Selection, Routing and Speed Optimization of Hybrid Ships
- Author
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Antti Ritari, Kirsi Spoof-Tuomi, Janne Huotari, Seppo Niemi, and Kari Tammi
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optimization ,mathematical programming ,ship design ,emission abatement ,hybrid propulsion ,speed optimization ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
This paper evaluates the effect of a large-capacity electrical energy storage, e.g., Li-ion battery, on optimal sailing routes, speeds, fuel choice, and emission abatement technology selection. Despite rapid cost reduction and performance improvement, current Li-ion chemistries are infeasible for providing the total energy demand for ocean-crossing ships because the energy density is up to two orders of magnitude less than in liquid hydrocarbon fuels. However, limited distance zero-emission port arrival, mooring, and port departure are attainable. In this context, we formulate two groups of numerical problems. First, the well-known Emission Control Area (ECA) routing problem is extended with battery-powered zero-emission legs. ECAs have incentivized ship operators to choose longer distance routes to avoid using expensive low sulfur fuel required for compliance, resulting in increased greenhouse gas (GHG) emissions. The second problem evaluates the trade-off between battery capacity and speed on battery-powered zero-emission port arrival and departure legs. We develop a mixed-integer quadratically constrained program to investigate the least cost system configuration and operation. We find that the optimal speed is up to 50% slower on battery-powered legs compared to the baseline without zero-emission constraint. The slower speed on the zero-emission legs is compensated by higher speed throughout the rest of the voyage, which may increase the total amount of GHG emissions.
- Published
- 2021
- Full Text
- View/download PDF
155. Projekt putničkog broda za plovidbu Mediteranom
- Author
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Gluščić, Petar and Slapničar, Vedran
- Subjects
cruise ship ,ship construction ,prototip ,Croatian Register of Shipping ,technical description ,TEHNIČKE ZNANOSTI. Brodogradnja. Osnivanje plovnih i pučinskih objekata ,GHS ,ship stability ,TECHNICAL SCIENCES. Shipbuilding. Design of Floating and Maritime Structures ,Hrvatski registar brodova ,stabilitet broda ,ship design ,osnivanje broda ,brod za krstarenje ,prototype ,tehnički opis ,konstrukcija broda - Abstract
U ovom radu proveden je postupak osnivanja putničkog broda za plovidbu Mediteranom. Projektnim zadatkom bilo je potrebno osigurati smještaj za 12 putnika u dvokrevetnim kabinama visoke klase uz 9 članova posade. U uvodnom dijelu objašnjen je postupak osnivanja broda te metode osnivanja. Nadalje je opisan putnički brod i njegove vrste, gdje je istaknut brod za krstarenje s detaljnim opisom. Prikazani su trendovi krstarenja u svijetu, Europi i Hrvatskoj. Temelj ovog rada bilo je kreiranje baze brodova, za koju je provedena regresijska analiza brodskih značajki. Iz baze brodova odabran je prototip te je provedena analiza njegovih značajki, nakon čega su sintezom tih značajki određene značajke projekta. Upotrebom programskog paketa GHS provjerene su značajke stabiliteta projekta, dok se konstrukcija odredila prema pravilima Hrvatskog registra brodova. Oprema, brodski vijak i glavni stroj određeni su prema zahtjevima HRB-a i sličnim brodovima. Nadalje, dan je kratki tehnički opis broda te su prikazani prostori na brodu, uključujući kabine za smještaj putnika i posade te zajedničke prostore. U konačnici su procijenjeni troškovi izgradnje broda. In this work, the process of ship design of a passenger ship for the navigation in the Mediterranean was carried out. The project task was to provide accommodation for 12 passengers in high-class double cabins with 9 crew members. In the introductory part, the process of ship design and the ship design methods are explained. Furthermore, the passenger ship and its types are described, where a cruise ship is highlighted with a detailed description. Cruise trends in the world, Europe and Croatia are presented. The basis of this work was creating the ships database, for which a regression analysis of ship features was carried out. A prototype was selected from the ships danabase and an analysis of its features was carried out, after which the project features were determined by synthesizing those features. Using the GHS software package, the stability features of the project were verified, while the construction was determined according to the rules of the Croatian Register of Shipping. Equipment, propeller and main engine are determined according to the requirements of HRB and similar ships. Furthermore, a brief technical description of the ship is given and the spaces on the ship are shown, including cabins for the accommodation of passengers and crew and common areas. In the end, the costs of building the ship were estimated.
- Published
- 2023
156. Effect of Void Content on the Mechanical Properties of GFRP for Ship Design
- Author
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Oh, Jaewon Jang, Maydison Maydison, Yeonjun Kim, Zhiqiang Han, and Daekyun
- Subjects
ship structure ,defects ,fabrication quality ,statistical analysis ,ship design - Abstract
Defects such as voids in composite materials often degrade the mechanical properties of laminates. Even if these materials are manufactured based on the design requirements, there is a possibility of instability occurring in these composite structures. In this study, several prototypes were developed based on changes in composite ship design conditions (glass fiber weight fraction and fabric combination type) using a hand lay-up approach. The fabrication quality was quantitatively defined using the burn-off test, and statistical analysis was performed. A combination of chopped strand mat and woven roving material laminates possessed relatively less void content in the entire glass content (Gc) region (30–70 wt%) compared to a chopped strand mat single-material laminate. The effect was more pronounced in the high-Gc region (50–70 wt%) than that in the normal-Gc region (30–50 wt%). The composite hull plate can be designed seamlessly according to changes in fabrication quality. To ensure safety, the thickness of the laminate must be greater than that specified in the ISO standards, regardless of the combination type in the normal-Gc region. As a result of the void content considered, the flexural strength in the single laminate decreased by 15.02%. Furthermore, 3.33% of the flexural strength calculation decreased in the combined laminate compared to that in the ISO rules. Thus, a single CSM material can be designed to be thicker than a combined-material laminate with the same Gc, while considering the void content on the mechanical properties.
- Published
- 2023
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157. Globally Convergent Hybridization of Particle Swarm Optimization Using Line Search-Based Derivative-Free Techniques
- Author
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Serani, A., Diez, M., Campana, E. F., Fasano, G., Peri, D., Iemma, U., Kacprzyk, Janusz, Series editor, and Yang, Xin-She, editor
- Published
- 2015
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158. Optimisation of a Diesel-Electric Ship Propulsion and Power Generation System Using a Genetic Algorithm
- Author
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Raphael Zaccone, Ugo Campora, and Michele Martelli
- Subjects
ship propulsion ,ship design ,genetic algorithm ,optimisation ,electric propulsion ,energy efficiency ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
In recent decades, the design of ship propulsion systems has been focusing on energy efficiency and low pollutant emissions. In this framework, diesel–electric propulsion has become a standard for many ship types and has proven its worth for flexible propulsion design and management. This paper presents an approach to the optimal design of diesel–electric propulsion systems, minimising the fuel consumption while meeting the power and speed requirements. A genetic algorithm performs the optimisation, used to determine the number and type of engines installed on-board and the engines’ design speed and power, selecting within a dataset of four-stroke diesel engines. The same algorithm is then adapted and applied to determine the optimal load sharing strategy in off-design conditions, taking advantage of the high flexibility of the diesel–electric propulsion plants. In order to apply the algorithm, the propulsion layout design is formulated as an optimisation problem, translating the system requirements into a cost function and a set of linear and non-linear constraints. Eventually, the method is applied to a case study vessel: first, the optimal diesel–electric propulsion plants are determined, then the optimal off-design load sharing and working conditions are computed. AC and DC network solutions are compared and critically discussed in both design and off-design conditions.
- Published
- 2021
- Full Text
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159. Scientific consciousness: an important dimension in ship innovation
- Author
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WU Chongjian
- Subjects
scientific consciousness ,innovation ,ship design ,noise and vibration reduction ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Abstract
Innovation features huge uncertainties and risks. According to statistics, less than one percent of discoveries and inventions convert successfully into innovations and real applications. The key element in converting innovative ideas into applications is the scientific consciousness of the innovators, which is very important for such open, complex and large-scale system engineering as naval architecture. Due to the lack of early warning for the cognition of dimension, many innovative ideas fail to convert into successful applications. Thus, enhancing scientific consciousness is important for holding the general interest and forming an integral vision of innovation so as to lead innovative design to the correct roads and approaches, and control risks in advance.
- Published
- 2017
160. A Method for Preliminary Estimation of the Length of Midship Body Block to Be Inserted During Ship’s Conversion
- Author
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Michalski Jan P.
- Subjects
ship design ,ship conversion ,increase of ship deadweight ,lengthening of ships ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Abstract
The paper presents a method for preliminary estimation of the length of the midship body block, which inserted in the original hull, increases the deadweight of the ship in line with a required quantity. The method may be useful for establishing the scope of conversion to better adjust the ship for transportation tasks. The problem is formulated by using a mathematical model so selected that its solution, under set of assumptions, is obtained in a closed analytical form. The presented method can be useful for application to pre-investment analysis of the ship conversion costs and functional profits.
- Published
- 2017
- Full Text
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161. Propulsion of a hydrogen-fuelled LH2 tanker ship
- Author
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Abdullah NFNR. Alkhaledi, Suresh Sampath, and Pericles Pilidis
- Subjects
Ship design ,Propulsion system ,Fuel Technology ,Renewable Energy, Sustainability and the Environment ,Liquefied hydrogen ,Liquid hydrogen tank ,Energy Engineering and Power Technology ,Condensed Matter Physics ,LH2 tanker - Abstract
This study aims to present a philosophical and quantitative perspective of a propulsion system for a large-scale hydrogen-fuelled liquid-hydrogen (LH2) tanker ship. Established methods are used to evaluate the design and performance of an LH2-carrier propulsion system for JAMILA, a ship designed with four cylindrical LH2 tanks bearing a total capacity of ∼280,000 m3 along with cargo and using the boil-off as propulsion and power fuel. Additionally, the ship propulsion system is evaluated based on the ship resistance requirements, and a hydrogen-fuelled combined-cycle gas turbine is modelled to achieve the dual objectives of high efficiency and zero-carbon footprint. The required inputs primarily involve the off-design and degraded performance of the gas-turbine topping cycle, and the proposed power plant operates with a total output power of 50 M.W. The results reveal that the output power allows ship operation at a great speed even with a degraded engine and adverse ambient conditions.
- Published
- 2022
162. Structural reliability analysis of FPSOs towards a rational design procedure
- Author
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Maerli, Andre
- Subjects
623.8 ,Ship design - Abstract
This report presents the structural reliability analysis of the hull girder ultimate strength for the ship shaped FPSO Triton. The ultimate strength of the hull girder was calculated using a component approach, where the behaviour of the hull is evaluated based on the behaviour of the single structural components. Three collapse conditions were investigated; failure initiated by plate compression, failure initiated by stiffener tension and failure initiated by stiffener compression. Only vertical bending moment has been considered and the hull girder loads are divided into stillwater and wave induced components. The two loading components have been considered independent and Ferry Borges - Castenheta load combination method has been applied to obtain load combination factors for the Full Load, Partial Load (50 % loaded) and Ballast condition. The distributions of the extreme values of the vertical wave bending moments (VWBM) were calculated, based on linear strip theory and a long-term formulation. The vertical mooring forces are small and they were considered to have an insignificant influence on the bending moment response. The reliability analysis was carried out using a SORM analysis. Annual reliability indices (ß) and probabilities of failures were calculated for hogging and sagging conditions. The calculated ß values were higher than the annual reliability indices proposed in DNV Classification Notes 30.6 for serious failures in redundant structures. This indicates that the design is safe and reliable for operation in this particular location.
- Published
- 1998
163. Труды Крыловского государственного научного центра
- Subjects
hydrodynamics ,ship design ,shipbuildning ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Published
- 2019
164. Efficient 3D Model Visualization System of Design Drawing Based on Mobile Augmented Reality
- Author
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Oh, Yeon-Jae, Kim, Eung-Kon, Jeong, Hwa Young, editor, S. Obaidat, Mohammad, editor, Yen, Neil Y., editor, and Park, James J. (Jong Hyuk), editor
- Published
- 2014
- Full Text
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165. Use of HLA Federation for the Evaluation of Naval Operations in Ship Design
- Author
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Tozzi, Davide, Valdenazzi, Federica, Zini, Aldo, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Kobsa, Alfred, Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, and Hodicky, Jan, editor
- Published
- 2014
- Full Text
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166. General on Ship Design
- Author
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Papanikolaou, Apostolos and Papanikolaou, Apostolos
- Published
- 2014
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167. Optimal Commonality Decisions in Multiple Ship Classes
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Corl, Michael J., Parsons, Michael G., Kokkolaras, Michael, Simpson, Timothy W., editor, Jiao, Jianxin (Roger), editor, Siddique, Zahed, editor, and Hölttä-Otto, Katja, editor
- Published
- 2014
- Full Text
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168. Overspecified vessel design solutions in multi-stakeholder design problems.
- Author
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Garcia, Jose J., Pettersen, Sigurd S., Rehn, Carl F., Erikstad, Stein O., Brett, Per O., and Asbjørnslett, Bjørn E.
- Subjects
- *
CONJOINT analysis , *ENGINEERING design , *INFORMATION asymmetry , *NAVAL architecture , *DECISION making , *REQUIREMENTS engineering - Abstract
Engineering design is characterized, in many cases, by the involvement of multiple stakeholders. The variety of stakeholders' expectations with regards to the output and outcome of a vessel design situation, and the differences in background, culture and information asymmetry among stakeholders, make it difficult to arrive at a common set of requirements and a mutually accepted vessel design solution. In this paper, we show how poor handling of expectations in multi-stakeholder arrangements may lead to overspecified design solutions and thereby, negatively affect business outcomes. We propose and test a set of metrics to measure the level of misalignment among stakeholders' expectations to identify and measure overspecification in vessel design alternatives. The measure can be used in tradeoff analysis against cost, in the decision process for selection among design alternatives. Hence, at equal cost, a higher degree expectation fulfillment may be preferred and selected. A case study is presented for the design of an offshore ship design based on a joint-venture ownership. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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169. Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form.
- Author
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Niklas, Karol and Pruszko, Hanna
- Subjects
- *
SEAKEEPING , *OFFSHORE structures , *CONTAINER ships , *SHIPS , *CASE studies , *NAVAL architecture , *PROPELLERS - Abstract
Increasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility enables performance of advanced seakeeping simulations for ships in a full scale. The paper presents CFD seakeeping analysis for a case study vessel in two variants: V-shaped bulbous bow hull form (as built) and innovative hull form (X-bow type). The study presents the influence of redesigning the ship on selected seakeeping aspects. The advanced CFD model, with the application of overset mesh technique, was described in detail. Selected numerical results were validated on the basis of experimental testing in a towing tank and showed good agreement. The approach demonstrated here of performing the CFD seakeeping simulations for the analysis of ship performance in a full scale and close to real loading conditions has direct application to the design process as well as in determination of optimal operational parameters of any ship. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
170. Hull form optimization in the conceptual design stage considering operational efficiency in waves.
- Author
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Jung, Yoo-Won and Kim, Yonghwan
- Abstract
This study focuses on the optimization of ship dimensions by considering hydrodynamic performance in waves. In actual seaways, a ship experiences speed loss due to environmental loads by waves and wind. Therefore, along with calm water resistance, speed loss in waves should be considered in the hull form design in order to improve operational efficiency in waves. However, a trade-off may be needed between total resistance on the ship and the speed loss in waves. To address this problem, Non-dominated Sorting Genetic Algorithm II, which is a multi-objective optimization method, is used to minimize the total resistance on a ship in seaways and the speed loss by additional resistance. In the optimization process, added resistance is predicted using a numerical method based on slender-body theory, Maruo's far-field formulation, and an empirical formula for added resistance in short waves. The speed loss in waves, which can be expressed by a weather factor (f
w ), is estimated using power–speed curves. This article introduces some examples of the sensitivity analysis of added resistance and speed loss in waves to the variations of ship dimensions. Finally, the optimization solutions on a Pareto front set are compared to a basis ship in terms of hull form, and the corresponding hydrodynamic performances are evaluated. [ABSTRACT FROM AUTHOR]- Published
- 2019
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171. REEFER VESSEL VERSUS CONTAINER SHIP.
- Author
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Čudina, Predrag and Bezić, Ana
- Subjects
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NAVAL architecture , *CONTAINER ships , *FREIGHT & freightage , *REFRIGERATED containers , *ECONOMICS , *BANANAS - Abstract
In the paper is presented a study of the economics of refrigerated cargoes transport with two specialized types of ship. Two modern ship designs are developed for the transport of refrigerated cargo, primarily bananas. One design is a reefer vessel with the ability to load a significant number of refrigerated containers on the main deck. The other design is a container ship specialized for the transport of refrigerated 40 feet containers. Both designs have the capacity to load the same mass of refrigerated cargo. Basic characteristics of the designs are compared, which can be the basis for answering the question: Which type of vessel to choose for the carriage of refrigerated cargo? [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
172. Versatility vs. retrofittability tradeoff in design of non-transport vessels.
- Author
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Rehn, Carl Fredrik, Garcia Agis, Jose Jorge, Erikstad, Stein Ove, and de Neufville, Richard
- Subjects
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NAVAL architecture , *SHIPS , *MONTE Carlo method , *UNCERTAINTY , *DECOMPOSITION method , *MATHEMATICAL optimization , *ECONOMICS - Abstract
Abstract In this paper, we study the relationship between economic performance and flexibility for non-transport vessels. More specifically, we investigate the difference between two means of achieving flexibility: retrofittability and versatility, i.e., the ability of a vessel to satisfy diverse needs with or without change of physical form, respectively. A model is presented to study this relationship, where we first generate design alternatives with relevant, flexible properties before we subsequently evaluate the design alternatives based on their expected discounted economic lifecycle performance. The evaluation model is based on a two-level decomposition of the planning horizon to handle temporal complexity, using scenario planning and Epoch-Era analysis (EEA) for long-term strategic considerations, and Monte Carlo simulation and optimization for medium-term tactical ship deployment. The proposed model is applied to an offshore construction ship design case. Findings indicate that retrofittability can increase economic performance significantly for non-transport vessels operating in an uncertain heterogeneous context. Highlights • This paper studies retrofittability and versatility as two aspects of flexibility in design non-transport vessels. • A vessel can satisfy a diverse set of needs with (retrofittability) or without (versatility) change of physical form. • Epoch-Era Analysis is used at the strategic level and Monte Carlo analysis at the tactical level. • The relationship between investment costs, flexibility, and revenue potential is studied. • Findings indicate that retrofittability significantly can increase economic performance for non-transport vessels. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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173. A Ship ‘For Which Great Neptune Raves’: The Sovereign of the Seas, la Couronne and seventeenth-century international competition over warship design.
- Author
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Redding, Benjamin W. D.
- Abstract
Charles I's great warship the Sovereign of the Seas is famed for its design, decoration and importance as a tool that heightened the image of English naval supremacy. By exploring its career, size, name and decoration, this article highlights the Sovereign of the Seas’ significance as a national symbol of political and cultural power. It argues that Charles's leading warship was developed as a reaction to naval advances and current affairs in Europe. Through a diverse range of evidence including diplomatic correspondence, printed texts and artwork from both English and French institutions, as well as relating this to similar advances in the Netherlands and Sweden, the Sovereign of the Seas’ development is internationally contextualized. By comparing it with other contemporary warships, most importantly la Couronne of France, it is shown that Charles's flagship was a product of a growing international theatre of maritime activity that was inspired by cultural and political competition, as much as it was by military escalation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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174. Techno-Economic Analysis of Photovoltaic Utilization for Lighting and Cooling System of Ferry Ro/Ro Ship 500 GT
- Author
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Faturachman Danny, Yandri Erkata, Tri Pujiastuti Endang, Anne Olga, Hendroko Setyobudi Roy, Yani Yahya, Susanto Herry, Purba Washington, and Krido Wahono Satriyo
- Subjects
green transportation ,energy saving ,solar energy ,energy dilemma ,ship design ,Environmental sciences ,GE1-350 - Abstract
The purpose of this study is to perform the techno-economic analysis of photovoltaic system utilization for lighting and cooling of Ferry Ro/Ro 500 GT. The world is facing a dilemma of increasing dependence on fossil energy with decreasing supply. This situation must be anticipated by all sectors by energy efficiency (EE) and utilizing renewable energy (RE). Especially for RE in the transportation sector, ships as consumers of oil energy can also take advantage of solar energy sources, for example for lighting and cooling. For that purpose, five steps must be taken. First, determine the design specifications. Second, determine the specifications of components of the PV system. Third, calculate the power required for lighting equipment. Fourth, calculate the power required for the cooling system. Fifth, make an investment comparison for propulsion systems between diesel engines and photovoltaic systems. The results show that the energy required for lighting and cooling system as well as for propulsion systems can be placed in the deck area of 148.8 m2 for all system components, such as; PV modules, charge controllers, batteries, and inverter. This study can provide an overview of the use of PV system in designing the environmentally new or renovation ships.
- Published
- 2021
- Full Text
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175. How virtual reality is used in industrial maritime design processes: Two case studies.
- Author
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Gernez, Etienne, Nordby, Kjetil, Archer Dreyer, Simon, Burås, Theodor, and Fauske, Jon Erling
- Subjects
- *
INDUSTRIAL design , *VIRTUAL reality , *NAVAL architecture , *SHIP models , *VIRTUAL communities , *FIELD research - Abstract
Virtual reality (VR) is increasingly integrated into maritime design processes, and there is a need to better understand how it can support ship designers in their work. Through mapping and interviews, we investigated how VR was used in two design projects in the maritime industry. We explored two questions: What type of design activities and conversations were facilitated by VR as a collaborative medium? When VR was not selected, what other media were used instead, and for what reasons? We found that despite access to VR, most design conversations were facilitated by emails containing screenshots, visual interpretations, and text annotations. VR was used on a few occasions, together with executable files and flythrough videos made with real-time rendered models generated in a game engine, and a web-based 3D model-sharing tool. The use of VR as a collaboration medium was enabled by a variety of design activities ranging from field studies to 2D sketching and 3D modeling. The cases show how VR needed to be integrated with other forms of communication and was seen as a supplement and not the main communication channel for design. The cases also show that the pipeline required for VR scenes creation enabled other forms of collaboration across different supports, such as web-based online collaboration tools. • Use of VR in design process is explored with a user-centered approach. • Two design cases are analysed to identify impact of, and alternatives to VR. • VR needs to be better integrated with existing design tools. • VR leads to 3D asset creation pipeline supporting collaboration across a variety of supports. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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176. Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment
- Author
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Michalski Jan P.
- Subjects
ship design ,deadweight and cargo handling optimization ,required freight rate ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Abstract
The paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate. The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the preliminary ship design or in the simulation of pre-investment transportation task studies.
- Published
- 2016
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177. Marine vessel powertrain design optimization: Multiperiod modeling considering retrofits and alternative fuels
- Author
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Antti Ritari, Janne Huotari, Kari Tammi, Mechatronics, Department of Mechanical Engineering, Aalto-yliopisto, and Aalto University
- Subjects
lifecycle evaluation ,synthetic fuels ,emission abatement ,energy storage ,Mechanical Engineering ,hydrogen ,ship design ,Ocean Engineering ,design optimization ,integer programming ,energy efficiency - Abstract
Over the coming decades, maritime transportation will transition from fossil hydrocarbon fuels to hydrogen, ammonia, and synthetic hydrocarbon fuels produced using renewable electricity as the primary energy source. In this context, a shipowner needs to identify a cost-efficient plan for the adoption of alternative fuels and onboard energy conversion system retrofits. This paper presents a multiperiod decision model for the selection of energy system components under increasingly stringent CO2 emissions regulations and cost forecasts over a multidecade planning horizon. The model considers the choice of newbuild architecture, timing of retrofits, component sizes, and allocation of fuels to converters with the objective of minimizing total cost of ownership (TCO). The decision problem is formulated as a discrete time multiperiod mixed-integer linear program. The application of the model is numerically illustrated for a Baltic Sea roll-on/roll-off ferry. The main findings are: (i) modifying the energy system with retrofits obtains 43% lower TCO compared to fuel switching alone; (ii) batteries contribute to 23% lower TCO; (iii) optimal component installation period can be shorter than their maximum lifetime; (iv) running an engine with hydrogen is favored over fuel cells and (v) hybrid propulsion is the key future-proofing design choice for short sea vessels.
- Published
- 2023
178. Tool For Rapid Generation Of Ship Hull Forms Used For Comparative Performance Analysis Of Various Ship Designs
- Author
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Prebeg, Pero, Smiljko Rudan, Simun Svilicic, and Radic-Rossi, Irena
- Subjects
ship hull form ,Zagrebacka ,ship design ,analytical model - Abstract
This is an abstract from the session entitled "Digital Approaches in Nautical Archaeology", at the 2023 annual meeting of the Society for Historical Archaeology. The hull of a ship at an archaeological site is almost always incomplete, so the resulting reconstructed hull lines inevitably include some uncertainties. These uncertainties contain the potential to improve the ship's theoretical performance. Hull definition based on analytically defined waterline curves allows easy generation and control of hull form variants. This paper focuses on creating different alternative hull forms in three steps. First, the parent hull form is generated by fitting the analytical model to the reconstructed hull lines. The second step involves defining the allowed hull changes. The third step is a multiobjective optimization of the problem in which the identified uncertainty ranges are used as constraints, while the ship's hydromechanics and navigation characteristics are used as objectives. The calculation of hydromechanical and seakeeping characteristics is based on low-fidelity models that are usually used in the initial stages of general ship design. The research contributes to the results of the project Numerical reconstruction in the archaeology of seafaring (NEREAS, IP-02-2020-3420) funded by the Croatian Science Foundation.
- Published
- 2023
- Full Text
- View/download PDF
179. Control of surface waves
- Author
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McHugh, Christine A.
- Subjects
623.8 ,Ship design - Published
- 1990
180. Motion and wave load analyses of large offshore structures and special vessels in waves
- Author
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Wu, Xiong-Jian and Price, W. G.
- Subjects
623.8 ,Ship design ,Wave loads ,Offshore structures ,Wave-structure interaction - Abstract
Predictions of the environmental loading and induced motional and structural responses are among the most important aspects in the overall design process of offshore structures and ships. In this thesis, attention is focused on the wave loads and excited bodily motion responses of large offshore structures and special vessels. With the aim of improving the existing theoretical methods to provide techniques of theoretical effectiveness, computational efficiency, and engineering practicality in marine and offshore applications, the thesis concentrates upon describing fundamental and essential aspects in the physical phenomenon associated with wave-structure interactions and deriving new methods and techniques to analyse offshore structures and unconventional ships of practical interest. The total wave force arising from such a wave-structural interaction is assumed to be a simple superposition of the potential and the viscous flow force components. The linear potential forces are solved by the Green function integral equation whilst the viscous forces are estimated based on the Morison's damping formula. Forms of the Green function integral equation and the associated Green function are given systematically for various practical cases. The relevant two-dimensional versions are then derived by a transformation procedure. Techniques are developed to solve the integral equation numerically including the interior integral formulation and, in particular, to tackle the mathematical difficulties at irregular frequencies. In applying the integral equations to solve problems with various offshore structures and special vessels, some modified, improved or simplified methods are proposed. At first, simplified method is derived for predictions of the surge, sway and yaw motions of elongated bodies of full sectional geometry or structures with shallow draft. Then, a new shallow draft theory is described for both three- and two-dimensional cases with inclusion of the finite draft effect. Furthermore, a three-dimensional strip method is formulated where the end effects of the body are fully taken into account. Finally, an approximation to the horizontal mean drift forces of multi-column offshore structures are presented. Some new findings are also discussed including the multiple resonances occurring in the motions of multi-hulled marine structures due to the wave-body interaction, the mutual cancellation effect of the diffraction and the radiation forces arising from a full shaped slender body, and so on. Further to those verification studies for individual methods developed, more comprehensive example investigations are given related to two industrial applications. One is a derrick barge semi-submersible with zero forward speed; and the other, a SWATH ship with considerable speed. By correlation of all the proposed approaches with available analytical, numerical and experimental data, the thesis tries to demonstrate a principle that as long as principal physical aspects in the wave-structure interaction problem are properly treated, an appropriately modified or simplified method works, performs well and, sometimes, even better.
- Published
- 1990
181. Design and Modeling of Catamaran Flat Plate Ship with Bottom Glass Concept to Improve Tourism Underwater in Bangsring Banyuwangi
- Author
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Hery Inprasetyobudi, Yeddid Yonatan Eka Darma, and Ahmad Hidayat
- Subjects
Naval Science ,Bending (metalworking) ,business.industry ,Snorkeling ,stability ,Naval architecture ,resistance ,Shipbuilding ,catamaran ,Hull ,ship design ,bottom glass ,Underwater ,business ,Tourism ,Mathematics ,Marine engineering - Abstract
The beauty of the beach and underwater of Bangsring beach make this beach one of the leading destinations in Banyuwangi Regency. However, until today how to enjoy the beauty of the underwater can exclusively be done by diving or snorkeling, which is quite troublesome and exhausting, especially for tourists who want to enjoy and looking entertainment in a simpler way. So the concept of bottom-glass in this design is offered as a problem solving in this study, while the concept of flat plate and flat-bottom is carried out to efficiently time and cost of shipbuilding, because with this flat plate concept, there is no rolling and other material bending process. The design of the main dimensions is made based on owner requirements are obtained based on field study and literature studies, then the main parameters are obtained (LOA = 12 m, total B = 5.6 m, B each hull = 0.94 m, hull spacing = 3.72 m, T = 0.7 m, H = 1.85 m, Vs = 10 knots). To maximize the design, 4 ship models were designed with these primary parameters, based on the analysis of resistance using Maxsurf Resistance, model 4 with a maximum resistance of 4.3 kN was chosen which tend to be more effective compared with the designs of model 1, model 2, and model 3 which has a maximum resistance of 8 kN, 4.9 kN and 5.3 kN. The results of the stability analysis carried out in this design with the load case 100%, 80%, 60%, 40%, and 20%, has met all requirements for intact stability IMO MSC.36 (63) for HSC multihull Annex 7.
- Published
- 2021
182. Estimates of the Decarbonization Potential of Alternative Fuels for Shipping as a Function of Vessel Type, Cargo, and Voyage
- Author
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Law, Li, Mastorakos, Epaminondas, Evans, Stephen, Law, LC [0000-0002-7383-5661], Mastorakos, E [0000-0001-8245-5188], Apollo - University of Cambridge Repository, Law, Li [0000-0002-7383-5661], and Mastorakos, Epaminondas [0000-0001-8245-5188]
- Subjects
alternative fuels ,Control and Optimization ,decarbonization ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology ,Building and Construction ,marine fuel ,tanker ,cargo ship ,maritime energy ,ship design ,containership ,Electrical and Electronic Engineering ,Engineering (miscellaneous) ,Energy (miscellaneous) - Abstract
Peer reviewed: True, Funder: National Research Foundation (NRF), Prime Minister’s Office, Singapore, Fuel transition can decarbonize shipping and help meet IMO 2050 goals. In this paper, HFO with CCS, LNG with CCS, bio-methanol, biodiesel, hydrogen, ammonia, and electricity were studied using empirical ship design models from a fleet-level perspective and at the Tank-To-Wake level, to assist operators, technology developers, and policy makers. The cargo attainment rate CAR (i.e., cargo that must be displaced due to the low-C propulsion system), the ES (i.e., TTW energy needed per ton*n.m.), the CS (economic cost per ton*n.m.), and the carbon intensity index CII (gCO2 per ton*n.m.) were calculated so that the potential of the various alternatives can be compared quantitatively as a function of different criteria. The sensitivity of CAR towards ship type, fuel type, cargo type, and voyage distance were investigated. All ship types had similar CAR estimates, which implies that considerations concerning fuel transition apply equally to all ships (cargo, containership, tankers). Cargo type was the most sensitive factor that made a ship either weight or volume critical, indirectly impacting on the CAR of different fuels; for example, a hydrogen ship is weight-critical and has 2.3% higher CAR than the reference HFO ship at 20,000 nm. Voyage distance and fuel type could result in up to 48.51% and 11.75% of CAR reduction. In addition to CAR, the ES, CS, and CII for a typical mission were calculated and it was found that HFO and LNG with CCS gave about 20% higher ES and CS than HFO, and biodiesel had twice the cost, while ammonia, methanol, and hydrogen had 3–4 times the CS of HFO and electricity about 20 times, suggesting that decarbonisation of the world’s fleet will come at a large cost. As an example of including all factors in an effort to create a normalized scoring system, an equal weight was allocated to each index (CAR, ES, CS, and CII). Biodiesel achieved the highest score (80%) and was identified as the alternative with the highest potential for a deep-seagoing containership, followed by ammonia, hydrogen, bio-methanol, and CCS. Electricity has the lowest normalized score of 33%. A total of 100% CAR is achievable by all alternative fuels, but with compromises in voyage distance or with refuelling. For example, a battery containership carrying an equal amount of cargo as an HFO-fuelled containership can only complete 13% of the voyage distance or needs refuelling seven times to complete 10,000 n.m. The results can guide decarbonization strategies at the fleet level and can help optimise emissions as a function of specific missions.
- Published
- 2022
- Full Text
- View/download PDF
183. The Hazards of Work in Merchant Shipping
- Author
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Walters, David, Bailey, Nick, Walters, David, and Bailey, Nick
- Published
- 2013
- Full Text
- View/download PDF
184. Ciencia y Tecnología de Buques
- Subjects
ship design ,hydrodynamics ,dynamics of ships ,vibrations and noise ,technology of ship construction ,marine engineering ,Naval Science - Published
- 2018
185. The Leader as an Architect : The Architect Must Be a Prophet
- Author
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Anderson, Edward G., Jr., Joglekar, Nitin R., Anderson Jr., Edward G., and Joglekar, Nitin R.
- Published
- 2012
- Full Text
- View/download PDF
186. A Reinforcement Learning Based Hybrid Evolutionary Algorithm for Ship Stability Design
- Author
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Turan, Osman, Cui, Hao, Chiong, Raymond, editor, Weise, Thomas, editor, and Michalewicz, Zbigniew, editor
- Published
- 2012
- Full Text
- View/download PDF
187. Historical Roots of the Theory of Hydrostatic Stability of Ships
- Author
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Nowacki, Horst, Ferreiro, Larrie D., Almeida Santos Neves, Marcelo, editor, Belenky, Vadim L., editor, de Kat, Jean Otto, editor, Spyrou, Kostas, editor, and Umeda, Naoya, editor
- Published
- 2011
- Full Text
- View/download PDF
188. Evolution of Analysis and Standardization of Ship Stability: Problems and Perspectives
- Author
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Nechaev, Yury, Almeida Santos Neves, Marcelo, editor, Belenky, Vadim L., editor, de Kat, Jean Otto, editor, Spyrou, Kostas, editor, and Umeda, Naoya, editor
- Published
- 2011
- Full Text
- View/download PDF
189. ANALYSIS OF THE ENERGY EFFICIENCY DESIGN INDEX WITH A PROPOSAL FOR IMPROVEMENT
- Author
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Predrag Čudina
- Subjects
energy efficiency design index ,ship design ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Abstract
This paper presents the actual method for the calculation of Energy Efficiency Deign Index and analyses the influence of particular variables on the resulted EEDI. Perceived inconsistencies of the actual method of calculation of the attained EEDI are presented with explanation of the influence that the actual calculation has on the design of new ships. Objections are clearly demonstrated on the example of conceptual design of Handy Bulk Carrier. Alternative proposals for improvement of calculation of attained EEDI are introduced. Suggested alterations eliminate observed deficiencies of the existing calculation.
- Published
- 2015
190. STUDI PERANCANGAN KAPAL FERRY TIPE CATAMARAN 1000GT
- Author
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Mardi Santoso
- Subjects
Ship Design ,Catamaran ,Ferry ,Parametric Design ,Ship Resistance ,Naval Science - Abstract
Pada tahap awal desain, untuk mendapatkan desain kapal yang optimum perlu dilakukan analisa untuk menentukan parameter utama dari kapal. Dalam penelitian ini akan dilakukan analisa terhadap pemilihan parameter utama dari kapal ferry catamaran kelas 1000GT untuk mendapatkan desain kapal ferry yang optimal. Parameter utama kapal ditentukan dari optimasi data utama kapal yang mirip yang dijadikan acuan set based design untuk mendapatkan ukuran kapal kapal ferry catamaran yang diinginkan. Geometri bentuk lambung kapal kemudian dioptimasikan dan dianalisa hambatannya menggunakan metode perhitungan, simulasi dan uji tarik. Rencana umum kapal kemudian dikembangkan untuk mendapatkan penataan ruang dan penentuan kapasitas kapal yang otimum. Dari hasil perhitungan menunjukkan bahwa kapal ferry catamaran 1000GT memiliki gross tonnage (GT) sebesar 1130GT dan nett tonnage (NT) 197GT. Dan daya mesin yang digunakan adalah 4 x 810 HP, untuk kecepatan dinas 15 knots.
- Published
- 2015
- Full Text
- View/download PDF
191. Surrogate Model-based Multi-Objective Optimization in Early Stages of Ship Design
- Author
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null Nanda Yustina and null Ari Saptawijaya
- Subjects
multi-objective optimization ,neural network ,ship design ,particle swarm optimizer ,surrogate model - Abstract
The abstract is the early stages of ship design, the decision of the ship's main dimensions significantly impacts the ship's performance and the total cost of ownership. This paper focuses on an optimization approach based on surrogate models at the early stages of ship design. The objectives are to minimize power requirements and building costs while still satisfying the constraints. We compare three approaches of surrogate models: Kriging, BPNN-PSO (Backpropagation Neural Network-Particle Swarm Optimizer), and MLP (Multi-Layer Perceptron) in two multi-objective optimization algorithms: MOEA/D (Multi-Objective Evolutionary Algorithm Decomposition) and NSGA-II (Non-Dominated Sorting Genetic Algorithm II). The experimental results show that MLP surrogate models get the best performance with MAE 6.03, and BPNN-PSO gets the second position with MAE 7.2. BPNN-PSO and MLP with MOEA/D and NSGA-II improve the design with around 58% smaller adequate power and 6% less steel weight than the original design. However, BPNN-PSO and MLP have lower hypervolume than Kriging for both optimization algorithms MOEA/D and NSGA-II. On the other hand, Kriging has the most inadequate model accuracy performance, with an MAE of 22.2, but produces the highest hypervolume, lowest computational time, and far lower objective values than BPNN-PSO and MLP for both optimization algorithms, MOEA/D and NSGA-II. Nevertheless, the three surrogate model approaches can significantly improve ship design solutions and reduce work time in the early stages of design., The abstract isthe early stages of ship design, the decision of the ship's main dimensions significantly impacts the ship's performance and the total cost of ownership. This paper focuses on an optimization approach based on surrogate models at the early stages of ship design. The objectives are to minimize power requirements and building costs while still satisfying the constraints. We compare three approaches of surrogate models: Kriging, BPNN-PSO (Backpropagation Neural Network-Particle Swarm Optimizer), and MLP (Multi-Layer Perceptron) in two multi-objective optimization algorithms: MOEA/D (Multi-Objective Evolutionary Algorithm Decomposition) and NSGA-II (Non-Dominated Sorting Genetic Algorithm II). The experimental results show that MLP surrogate models get the best performance with MAE 6.03, and BPNN-PSO gets the second position with MAE 7.2. BPNN-PSO and MLP with MOEA/D and NSGA-II improve the design with around 58% smaller adequate power and 6% less steel weight than the original design. However, BPNN-PSO and MLP have lower hypervolume than Kriging for both optimization algorithms MOEA/D and NSGA-II. On the other hand, Kriging has the most inadequate model accuracy performance, with an MAE of 22.2, but produces the highest hypervolume, lowest computational time, and far lower objective values than BPNN-PSO and MLP for both optimization algorithms, MOEA/D and NSGA-II. Nevertheless, the three surrogate model approaches can significantly improve ship design solutions and reduce work time in the early stages of design.
- Published
- 2022
192. Lessons for Turbulence
- Author
-
Kupiainen, Antti, Alon, N., editor, Bourgain, J., editor, Connes, A., editor, Gromov, M., editor, and Milman, V., editor
- Published
- 2010
- Full Text
- View/download PDF
193. The Heritage of Archimedes in Ship Hydrostatics: 2000 Years from Theories to Applications
- Author
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Nowacki, Horst, Paipetis, S. A., editor, and Ceccarelli, Marco, editor
- Published
- 2010
- Full Text
- View/download PDF
194. Ships, Geography, and Humanism
- Author
-
Unger, Richard W. and Unger, Richard W.
- Published
- 2010
- Full Text
- View/download PDF
195. Making Maps without Ships, with Ships
- Author
-
Unger, Richard W. and Unger, Richard W.
- Published
- 2010
- Full Text
- View/download PDF
196. Business Experiment Ship Building
- Author
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Kraemer-Fuhrmann, Ottmar, Raekow, Yona, Stanoevska-Slabeva, Katarina, editor, Wozniak, Thomas, editor, and Ristol, Santi, editor
- Published
- 2010
- Full Text
- View/download PDF
197. Optimising Vessel Layout Using Human Factors Simulation
- Author
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Deere, Steven J., Galea, Edwin R., Lawrence, Peter J., Klingsch, Wolfram W. F., editor, Rogsch, Christian, editor, Schadschneider, Andreas, editor, and Schreckenberg, Michael, editor
- Published
- 2010
- Full Text
- View/download PDF
198. Practical approach to calculating the hydrodynamic oscillating loads of a ship propeller under non-uniform wake field.
- Author
-
Ghassemi, Hassan
- Subjects
- *
HYDRODYNAMICS , *NAVAL architects , *OSCILLATIONS , *SHIP propulsion , *SHIP hydrodynamics - Abstract
Propellers usually operate in the ship's stern, where the inflow of the non-uniform wake generates oscillating loads and changes the hydrodynamic performance. Therefore, determination of the forces on propellers and hydrodynamic performance due to a non-uniform wake field are the challenging problems for naval architects and hydrodynamists. The main objectives of the present study are to assess the hydrodynamic performance for a single blade and all the blades. The propeller is a B-series propeller under non-uniform wake field behind the Seiun-Maru (hereafter SM) ship hull. A practical approach is employed to calculate the hydrodynamic oscillating loads of the ship propeller under a non-uniform wake field. Results of the computations on the propeller behind the SM ship, due to a non-uniform wake field, are presented and analyzed using classical mathematical methods over a single cycle. The results show that a variation of thrust with the discussed parameters is the same as that shown for torque, also the blade-frequency of the total force, thrust and torque is an increasing function of radial sections, whereas these parameters decrease with increasing radial blade sections. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
199. A combined approach based on Subdivision Surface and Free Form Deformation for smart ship hull form design and variation.
- Author
-
Coppedé, Antonio, Vernengo, Giuliano, and Villa, Diego
- Subjects
DEFORMATIONS (Mechanics) ,SHIP hull fouling ,MATHEMATICAL optimization ,POLYGONS ,NAVAL architecture - Abstract
Techniques for shape representation and further modification of a hull surface definitely play a key role in both the design of new buildings and in the optimisation of the existing ones. The simplification of the methods is the goal to reach in order to create useful tools for real applications. A new approach for hull shape modification is proposed. It is based on a combination of the Subdivision Surface technique for hull surface modelling and Free Form Deformation for shape variation. The formal relation between the two methods is established by the Free Form Deformation control volume and the Subdivision Surface control polygon, introducing significant simplification to the definition of the transformation. The new approach is described in detail highlighting its benefits. Its effectiveness is finally proved by an example of application on a real hull shape, where a combination of a local and global modification has been analysed. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
200. Efficiency constraints of energy storage for on-board power systems.
- Author
-
Georgescu, Ioana, Godjevac, Milinko, and Visser, Klaas
- Subjects
- *
ENERGY storage , *ENERGY consumption , *ENERGY management , *ELECTRICAL energy , *MATHEMATICAL formulas - Abstract
Energy storage has the potential to reduce the fuel consumption of ships by loading the engine(s) more efficiently. The exact effect of on-board energy storage depends on the ship functions, the configuration of the on-board power system and the energy management strategy. Previous research in this area consists of detailed modelling, design, and comparisons of specific on-board power systems for explicitly defined operational profiles. The necessary inputs for these studies are rarely known initially however, since the effect of energy storage on the fuel consumption is not necessarily always positive, it is essential to know the limitations of fuel savings obtained by an on-board energy storage early in the design stage. To that effect, the paper proposes a set of algebraic formulas for the equivalent specific fuel consumption of on-board power systems equipped with electrical energy storage, which give a quick estimation of the maximum fuel savings obtainable. Depending on the specific fuel consumption of the prime mover, the loading point of the system and the use scenario of the battery, relative efficiency improvements can vary between −48% and 57%. A set of design guidelines is also proposed based on the obtained results. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
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