100 research outputs found
Linkage/association study of a locus modulating total serum IgE on chromosome 14q13-24 in families with asthma
No full textBackground: A study was undertaken to validate a locus modulating total serum IgE levels on 14q13–24.Methods: A linkage and association study was performed between total serum IgE and a panel of seven microsatellites which map to the 14q13–24 region in 69 families with asthma recruited from Leeds, UK.Results: Non-parametric, multipoint, sib pair analysis showed no evidence of genetic linkage between the quantitative trait "log IgE" and any of the tested markers. However, a significant association was observed between locus D14S63 (14q23) and total serum IgE (p = 0.017). Allelic analysis showed an association between low total IgE and allele 157 of D14S63 (p = 0.01, OR = 0.63, 95% CI 0.44 to 0.90). Modelling of allele 157 genotypes as a continuous covariate indicated evidence of a significant inverse linear trend across the three genotypes where 157 homozygotes had the lowest mean log IgE (p = 0.045). Association of D14S63 with log IgE was confirmed in the analysis of a combined dataset of 53 families from Southampton, UK and the 69 families from Leeds (total 122 families). An association was observed at the locus level (p = 0.022) and the allelic level where allele 165 showed an association with high total IgE (p = 0.001, OR = 3.79, 95% CI 1.54 to 9.7) and allele 157 showed an association with low total IgE (p = 0.041, OR = 0.77, 95% CI 0.6 to 0.99). The transmission disequilibrium test was positive for allele 165 (p<0.05) and negative for allele 157 (p>0.05).Conclusions: Despite the lack of linkage, the findings of this study support the previous observation of a gene(s) at 14q23 that modulates total serum IgE
BSc Maritime Technology Curriculum Revision: What Will the Future Naval Architect Look Like?
No full textWith the current curriculum developed and implemented in phases since 2013, it is time to evaluate and review the BSc curriculum. For this revision, the success and issues of the previous revision, the changes in our field and society, and the recent insights from educational studies are all reviewed to form the basis of this update. Current developments, like energy and autonomy transitions in the sector, as well as extra attention to learning processes and socialization, as a result of COVID-19, are all reviewed. The goals and vision will be discussed as well as current trends in the industry, science and education sciences. This will form the basis for a curriculum revision, followed by a comparison with related education to verify that a sound basis continues to exist. In the discussion, relevant considerations for Maritime Education, in general, will be drawn from this experience to support others in their updates.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Ship Design, Production and Operation
Optimizing the shipbuilding layout of Damex Shipbuilding and Engineering for cost efficiency
No full textIn this master thesis the shipyard layout of Damex Shipbuilding and Engineering is optimized for cost efficiency.Ship ProductionDPOMechanical, Maritime and Materials Engineerin
The use of digital games in academic maritime education: a theoretical framework and practical applications
No full textIn search of a way to bring back the positive aspects of an internship into the curriculum, TU Delft identified serious games as a potential solution. The literature studied showed that games could increase motivation and understanding, leading to improve knowledge retention. This paper has brought these insights together in a framework identifying the benefits that contribute to knowledge retention but also the requirements and risks for the application of serious games to be addressed. These insights were used to explain the success of a longstanding business game course for advanced students first. Next was the development of a virtual reality practice in a first-year course to replace the lost internship. In this case, knowledge retention was improved significantly, albeit only by 5%. Furthermore, in light of the developed framework, the VR simulation is a more balanced approach with fewer risks compared to the more extensive master course.Ship Design, Production and Operation
Investigation of the Application of adhesively bonded lifting lugs in ship building
No full textDefects are produced when lifting lugs being welded on ship sections during the building process. The large amount of heat produced in the welding work causes “heat affected zone” in the base metal on sections and destroys painted coatings on the plates; and residual stress decreases the mechanical performance of the steel plates. To eliminate the defects, it is hypothesized that “structural adhesive bonding” can replace welding for installing lifting lugs to some extent. An investigation of the application of adhesively bonded lifting lugs in ship building is processed to give methods for the application and check the feasibility of replacing welded lifting lugs with adhesively bonded lifting lugs. In the research, a serious of rules for adhesively bonded lifting lugs is adapted from rules for welded lifting lugs; “structural adhesives”, “adhesive bonding joints”, “the shape and geometry of lifting lugs” and “positions for installation” are investigated. Then adhesively bonded lifting lugs are designed based on the adapted rules; and then improved after the evaluation by FEM simulation. The results show that adhesively bonded lifting lugs can replace welding lifting lugs with high probability when the capacity is less than 20ton; when the capacity is between 20ton and 30ton, limitations such as “not enough bonding area” and “no positions for installation” constrain the replacement. When the capacity of a lifting lug is above 30ton, adhesively bonded lifting lugs cannot replace welded lifting lugs.Mechanical, Maritime and Materials EngineeringMarine and Transport Technolog
Shipping and shipbuilding scenario evaluations through integration of maritime and macroeconomic models
No full textThis research focusses on the use of consistent scenarios to help ship owners, banks and other parties with an interest the maritime business get a better grip on the future. Three levels of detail can be distinguished for the maritime industry. The macroeconomic level is the highest and focusses on the behaviour of countries and the trade between them. The next level is that of the maritime markets, newbuilding, secondhand sales, scrapping and trading. The last level is at company level, optimizing the assignment of vessels. While for each level models exists in many shapes and forms. The strength of this thesis is to combine the latest ideas and techniques into one single model spanning all three levels. It creates a much more consistent picture of the effects of a scenario on the future and many different scenarios can be tested. Also the effect of a set of scenarios on the profitability of a vessel can be investigated. The downside is the amount of data required for such a model, as well as the fact that mistakes (in this data) are carried over within the model. The model now available is a good first attempt at such a model. Some simple scenarios were able to demonstrate realistic, but counterintuitive behaviour, that would have been missed with a less complex model. This supports the notion that such a model is necessary for understanding the complex nature of the maritime economy.Marine & Transport TechnologyMechanical, Maritime and Materials Engineerin
Improving the execution of complex projects at conversion yards: The development of a functional framework using a systems approach
No full textThis paper aims to improve the execution of complex projects by the development of a functional framework using a systems approach guided by the six steps from the Deweyan Inquiry. Readers unfamiliar with the systems approach I recommend reading the chapters 1,2,4 and 5 of the Delft Systems Approach(Veeke,2008). The developed framework offers a common approach in an empty, conceptual model. In this model the different functions, their relations and interdependencies are defined, offering a common approach for the controlled and repetitive execution of complex projects while maintaining the flexibility to tune the model to a specific project.ProductionShip Design, Production and OrganisationsMechanical, Maritime and Materials Engineerin
The potential of adhesive bonding in shipbuilding
No full textMechanical, Maritime and Materials EngineeringMarine and Transport TechnologyTransport Engineering and Logistics2010.TEL.748
An evaluation of suitable methods to deal with deep uncertainty caused by the energy transition in ship design
No full textThe maritime energy transition presents deep uncertainties that are difficult to deal with in the current ship design process. Even though other fields have stressed using adaptive strategies and explorative methods to deal with deep uncertainty, it is rarely included in ship design. Therefore, this paper compares three applicable methods to investigate how such aspects could support the design process. Each method is found to offer specific improvements to decision making, but no separate method meets the established criteria to the desired degree. The methods are found to be complementary, and by developing a combined method for ship design, ships can be better prepared to deal with deep uncertainty.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Ship Design, Production and Operation
Study of Shipbuilding Competitiveness: Benchmarking analysis as a tool to measure shipyards' competitiveness with a focus on Asian yards
No full textThe shipbuilding industry is not a standalone industry. It integrates with the shipping market, and therefore one characteristic of the shipbuilding industry is complexity. Competitiveness is a multi-dimensional concept that can be measured in numerous ways. The author found that these multi-dimensional concepts can better be translated into three objectives. Three methods are evaluated to find which one is the most appropriate when measuring the shipyard's competitiveness. To find which method is the most appropriate, the author conducted the Analytical Hierarchy Process and found that benchmarking analysis is the best method. Data Envelopment Analysis (DEA) is chosen due to its versatility, cautious estimation, and non-parametric characteristics. Data Envelopment Analysis is an operation research method that uses mathematical formulation to find benchmarks among units under study. The first model uses deliveries as output, dock area and number of employees as inputs. The second model uses price/CGT and duration/CGT as inputs, and new contracts as outputs. The models investigated 20 shipyards from Japan, China, South Korea, and Vietnam. The results show that Chinese yards are very efficient when it comes to attracting new orders. However, in terms of allocating its resources, Chinese yards are very inefficient. Japanese yards are very efficient in both models. Most of the Japanese yards are frontiers. Korean yards, on the other hand, are the winner for mega-sized yards, but not in the medium-sized shipyards. Data Envelopment Analysis (DEA)'s results show the efficiency between the output and input of a system with a quantifiable value and provide a point of improvement by increasing output (for output-oriented) or decreasing input (for input-oriented). The insight can be derived from the results by analyzing the efficiency score and lambda values.Marine Technology | Ship Design, Production and Operation
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