The Quadrimaran Reexamined

2015 ◽  
Author(s):  
William A. Hockberger
Keyword(s):  
High Performance ◽  
Early Stage ◽  
Ship Design ◽  
Technical Problems ◽  
Additional Information ◽  
Marine Vehicles ◽  
Detail Design ◽  
Marine Industry ◽  
And Performance ◽  
Met Expectations

The Quadrimaran was invented in France in the mid-1980s by Daniel Tollet. It was an inspired design and a radical departure from traditional ship design by a man from outside the marine industry unconstrained by industry technical practices and education. Technical experts could see it would entail more structure and subsystems than other high-performance vessels, but its promise was that those penalties would be more than offset by its claimed low power and fuel consumption. A prototype/demonstrator, Alexander, was built in 1990 and operated for five years carrying and impressing many hundreds of riders. Alexander performed beautifully and appeared to bear out what was claimed. Contracts for several Quadrimarans of different sizes came quickly, especially considering how conservative an industry this is. That was significantly due to Tollet's personal charisma and skill in selling riders on the dream of carrying passengers and freight over the water fast and in comfort, yet economically. Great skepticism prevailed in some quarters, especially among naval architects knowledgeable about AMVs (advanced marine vehicles) and early-stage whole-ship design. At technical meetings, one Quadrimaran principal would comment, for example, "Why would you carry freight across the Atlantic at 38 knots on 230,000 horsepower (a reference to the planned Fastship Atlantic TG-770) when you could do it at 60 knots on only 65,000 horsepower?" Listeners would ask how this could be possible, and he would assert again that the Quadrimaran could do it, but would decline to explain. Respected technical people were working with Tollet and his company and becoming convinced of the Quadrimaran's merit. Along with the contracts came engineers with experience in ship detail design and construction (very different from early-stage whole-ship design), or responsibilities for assessing and approving ships for service. Others were with engine and equipment suppliers. Their opinion that there was something unique and special about the Quadrimaran gave it credibility and influenced more people to accept the major claims made for it. Some dismissed the most extreme claims but still accepted the idea that the Quadrimaran was capable of unusually high performance - considerably less than was being claimed, perhaps, but high nevertheless. In hindsight it is clear the skeptics were right. Results never met expectations, nor could they have. In reality, the Quadrimaran has aspects that inherently prevent it from achieving the characteristics and performance its inventor believed attainable. It cannot be built in a commercially useful size and actually perform as intended. Why this is so will be explained. A crucial fact in the Quadrimaran's history is that Daniel Tollet and his close associates believed strongly that naval architects and engineers who had been immersed in working with the existing ship types would be unable to give the Quadrimaran the very different treatment they believed it required. (Their own educations and professional work were nontechnical.) Such people were excluded from the development of Quadrimaran designs, and the belated discovery of many fundamental technical problems can be attributed to this. The company Tollet established had a number of names over the years, and other associated entities were created at times for various purposes. In this paper they are referred to collectively as QIH (Quadrimaran International Holdings) so as not to confuse things unnecessarily. In 2004 QuadTech Marine LLC was established and acquired the Quadrimaran patent (US Patent No. 5,191,849) and related intellectual property from QIH. QuadTech laid out an extensive R&D program to close gaps in the technical background and address identified issues. In the process, additional information on earlier QIH projects and products was obtained and studied, which brought to light problems that significantly compromised the Quadrimaran's prospective performance and utility. The resulting much-reduced set of potential uses and users led the company to effectively stop pursuing Quadrimaran projects after 2009. (Note: The author was Chief Technology Officer for QuadTech Marine during 2006-9, studying the Quadrimaran and planning the R&D.)

scholarly journals Application of Boosting Regression Trees to Preliminary Cost Estimation in Building Construction Projects

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yoonseok Shin
Keyword(s):  
Cost Estimation ◽  
Construction Projects ◽  
High Performance ◽  
Learning Algorithm ◽  
Early Stage ◽  
Construction Project ◽  
Regression Tree ◽  
Building Construction ◽  
Regression Problem ◽  
Additional Information

Among the recent data mining techniques available, the boosting approach has attracted a great deal of attention because of its effective learning algorithm and strong boundaries in terms of its generalization performance. However, the boosting approach has yet to be used in regression problems within the construction domain, including cost estimations, but has been actively utilized in other domains. Therefore, a boosting regression tree (BRT) is applied to cost estimations at the early stage of a construction project to examine the applicability of the boosting approach to a regression problem within the construction domain. To evaluate the performance of the BRT model, its performance was compared with that of a neural network (NN) model, which has been proven to have a high performance in cost estimation domains. The BRT model has shown results similar to those of NN model using 234 actual cost datasets of a building construction project. In addition, the BRT model can provide additional information such as the importance plot and structure model, which can support estimators in comprehending the decision making process. Consequently, the boosting approach has potential applicability in preliminary cost estimations in a building construction project.

Reducing Detail Design and Construction Work Content by Cost-Effective Decisions in Early Stage Naval Ship Design

2014 ◽  
Author(s):  
Robert G. Keane ◽  
Laury Deschamps ◽  
Steve Maguire
Keyword(s):  
Early Stage ◽  
Cost Effective ◽  
Ship Design ◽  
Defense Acquisition ◽  
Design Decisions ◽  
Stage Design ◽  
Work Content ◽  
Detail Design ◽  
Naval Ship ◽  
Early Stage Design

The Office of the Under Secretary of Defense, Acquisition, Technology and Logistics (AT&L) recently presented analyses of cost and schedule growth on Major Defense Acquisition Programs (MDAPs)over the last 20 years (2013, 2014). For naval ships, AT&L (2013) concluded that contract work content growth (not capability growth) dominates total cost growth statistically. In addition, costs-over-target are significant and reflect poor cost estimation or faulty framing assumptions. AT&L (2014) also concluded prices on fixed-price contracts are only “fixed” if the contractual work content remains fixed, but this is often not the case. The authors show that under-sizing the ship during concept design studies increases ship outfit density and adds complexities to the design. These early stage design decisions on sizing the ship are a major contributor to unnecessary work content growth later in Detail Design and Construction (DD&C) that cannot be eliminated no matter how productive the shipbuilder. However, new ship design methods are being developed and integrated with legacy physics-based design and analysis tools into a Rapid Ship Design Environment (RSDE)that will enable a more rational process for initially sizing ships. The authors also identify the need for early stage design measures of complexity and ship costing tools that are more sensitive to these measures, and proposed solutions that will aid decision-makers in reducing DD&C work content by making cost-effective design decisions in early stage naval ship design.

Ensuring Successful Ship Construction Outcomes: Using More Physics-Based Design Tools in Early Concept Design

2012 ◽  
Author(s):  
Robert G. Keane
Keyword(s):  
Collaborative Design ◽  
High Performance ◽  
Early Stage ◽  
Ship Design ◽  
Design Tools ◽  
Concept Design ◽  
Ship Construction ◽  
Design Engineers ◽  
Naval Ship ◽  
American Society

The Navy has experimented with many ways to improve the producibility of naval ship designs. In terms of effectiveness - does the ship do what it is supposed to do - the Navy has been reasonably successful. However, in terms of efficiency - are the ships efficient to produce and own - there is still much room for improvement. Design for producibility – being able to efficiently produce a warship - must start during the earliest stages of concept design and continue to be addressed during the subsequent pre-production processes. However, many early stage naval ship design engineers either do not recognize this need or do not know how to design for producibility. A number of improvements to early stage ship design capabilities are being developed in order to make the process both effective and efficient. This paper addresses the critical stage of the collaborative Design-Build-Own process of initially sizing the hull during concept design. The author proposes the development and use of more physics-based design tools during concept design, such as those being developed under the DoD High Performance Computing Modernization Program’s Computational Research & Engineering for Acquisition Tools & Environments (CREATE) – SHIPS Project. These new ship design methodologies will enable conceptual design engineers to adequately size a ship to meet military performance requirements and to have a low enough ship density to ensure successful ship construction outcomes. The director of a Netherlands’ shipyard which designs and builds surface combatants recently stated at a luncheon of the American Society of Naval Engineers (ASNE), “We learned a long time ago to give ourselves enough space to build a ship – steel is cheap, air is free!”

Reducing Detail Design and Construction Work Content by Cost-Effective Decisions in Early-Stage Naval Ship Design

2016 ◽  
Vol 32 (02) ◽  
pp. 110-123
Author(s):  
Robert G. Keane ◽  
Laurent Deschamps ◽  
Steve Maguire
Keyword(s):  
Early Stage ◽  
Cost Effective ◽  
Ship Design ◽  
Defense Acquisition ◽  
Design Decisions ◽  
Stage Design ◽  
Work Content ◽  
Detail Design ◽  
Naval Ship ◽  
Early Stage Design

The Office of the Under Secretary of Defense, Acquisition, Technology, and Logistics (AT&L) recently presented analyses of cost and schedule growth on Major Defense Acquisition Programs (MDAPs) over the last 20 years (2013, 2014). For naval ships, AT&L (2013) concluded that contract work content growth (not capability growth) dominates total cost growth statistically. In addition, costs-over-target are significant and reflect poor cost estimation or faulty framing assumptions. AT&L (2014) also concluded prices on fixed-price contracts are only "fixed" if the contractual work content remains fixed, but this is often not the case. We show that under-sizing the ship during concept design studies increases ship outfit density and adds complexities to the design. These early-stage design decisions on sizing the ship are a major contributor to unnecessary work content growth later in Detail Design and Construction (DD&C) that cannot be eliminated no matter how productive the shipbuilder. However, new ship design methods are being developed and integrated with legacy physicsbased design and analysis tools into a Rapid Ship Design Environment (RSDE) that will enable a more rational process for initially sizing ships. We also identify the need for early-stage design measures of complexity and ship costing tools that are more sensitive to these measures, and propose solutions that will aid decision-makers in reducing DD&C work content by making cost-effective design decisions in early-stage naval ship design.

Computer Definition of Ship Characteristics

1968 ◽  
Vol 5 (03) ◽  
pp. 288-306
Author(s):  
Thano P. Boumis
Keyword(s):  
Cost Effective ◽  
Ship Design ◽  
Computer Application ◽  
Analysis And Design ◽  
Governmental Agencies ◽  
Detail Design ◽  
Marine Industry ◽  
Current Program ◽  
Program Construction ◽  
Definition Of

Computer techniques are widely used by the marine industry to implement the phases of conceptual, preliminary, and detail design of ships. Application of computers to augment the definition of ship characteristics is rapidly increasing. Governmental agencies and leading private concerns have already resorted to the use of computers and expend considerable efforts in program developments. Computer application is a new cost element in ship design; thus, consideration should be given to developments that will render the computer a useful and cost-effective tool to the industry. Cost-effectiveness compels the analyst and the designer to distinguish between mere use which they should avoid, and usefulness which they should seek. The increasing trend to employ systems analyses to ship design is greatly facilitated by using computers. System and subsystem definition and optimization offer excellent opportunity for useful computer application. The desired extent of analysis and design dictates the function and the appropriate program construction to be employed. Current practices and future trends indicate that short, specific programs are usually the most useful and that large programs should be developed using special techniques and processors only if the programs would serve an existing or projected need. This discussion outlines pertinent thoughts on current program utilization and also on development and construction techniques to facilitate computer definition of ship characteristics. Discussers Henry Rumble H. Chatterton Reuven Leopold

Hull Form Exploration in the Early Stage of Design

2015 ◽  
Author(s):  
Igor Mizine ◽  
Charles Rogers ◽  
Bruce D. Wintersteen
Keyword(s):  
Design Process ◽  
Structural Design ◽  
Early Stage ◽  
Ship Design ◽  
Synthesis Process ◽  
Hull Form ◽  
Design Synthesis ◽  
Stage Design ◽  
Early Stage Design ◽  
And Performance

The objective of the ship design synthesis process is to derive a ship’s physical and performance characteristics based on mission requirements and selected technology and configuration options. To accomplish this objective an effective compromise must be achieved between the many competing requirements and constraints that form the available design space. The engineering disciplines that are addressed during the design synthesis process include; mission systems and cargo requirements, hull form geometry, hull subdivision, deckhouse geometry and subdivision, structures, appendages, resistance, propulsors, machinery arrangements, weight estimates, required arrangeable area and volume, intact stability and seakeeping. The hull form is a critical component of the design synthesis process. The hull is subdivided with decks and bulkheads to establish the compartment configuration (to the watertight compartment level) within the hull and to determine if the required mission capabilities and systems can be accommodated. The hull form is the principal boundary for the structural design. Required appendages must be integrated with the hull form. The propulsor design (propellers, waterjets, etc.) depends on resistance and the water flow around the hull form. The hull form significantly drives the propulsion power required and significantly impacts the location of the principle machinery equipment within the hull. While the weight estimates draw directly from the structural design and machinery equipment and other known data (mission systems), many of the other weight groups are estimated by algorithms. These algorithms are very dependent on hull volume and the distribution of that volume within the hull. Hull hydrostatics, stability and seakeeping are all very dependent on the hull form. The investigation of hull form variations during early stage design has long been limited by the capabilities present in the available design tools and their supporting framework. While some excellent hulls have been designed in parallel or preceding the overall ship design process, the limitations in design tools and their integration have often left the design process with a significant unknown as to whether the selected hull form is truly the best configuration for the ship and its mission. The hull form has a significant influence on almost every subsystem and discipline involved in ship design, not just hydrodynamics The routine Navy practice during early stage design has been to perform analysis based on a single baseline hull form point design, which is usually derived from dimensional scaling of existing designs or prototypes. This practice limits analysis of the hull form related characteristics and performance in concert with other tradeoffs and analysis of the disciplines that are very much influenced by the hull form. In some cases, this approach has perpetuated the undesirable characteristics of the selected starting hull form. In many, if not most recent designs, the limitations of our design process capabilities have produced less than optimal hull form configurations, especially in view of the operational profile, which determines the life cycle cost. In addition, late design improvements in hull form such as stern flaps or bulb changes result in the ship exceeding the design requirements that drive cost into the ship, i.e. larger engines installed then required to meet the ship’s KPP for speed. The paper explains how it is possible to overcome this limitation and how to restructure the ship design processes to facilitate effective investigation of hull form variations as part of the design synthesis process. The development of the hull form along with the overall development of the ship design configuration can be effectively integrated during the early Mizine Hull Form Exploration in the Early Stage of Design 2 stages of design when sufficient flexibility remains to enable the most effective design across all disciplines. This paper addresses the process, tools, and methodologies the authors have been developing and applying for several ship design projects to enable the effective development of the hull form and the investigation of hull form variations and their impact on the overall ship effectiveness. The approach used to facilitate the effective integration of the range of design and analysis tools necessary to support the process is described. The methodologies and theories used to investigate the potential range of hull form alternatives and assess their relative performance are presented. Examples of analyses done for actual design projects are provided, along with lessons-learned and recommendations for further refinements and improvements to the processes presented.

Trace nanoanalysis

1994 ◽  
Vol 52 ◽  
pp. 940-941
Author(s):  
D. E. Newbury ◽  
R. D. Leapman
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Detection Efficiency ◽  
Volume Element ◽  
And Performance ◽  
Trace Constituents ◽  
Secondary Ion ◽  
Concentration Levels ◽  
Structure Properties

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).

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