Search results for "Ocean engineering"
showing 10 items of 404 documents
Parametric Design of Sailing Hull Shapes
2006
The author presents an original algorithm aimed at automatically generating the hull shape of a sailing yacht starting from an initial set of parameters. The procedure consists of two steps. First one keel line and a Designed Water Line (DWL in the following) are faired according to a set of parameters, say length of water line, canoe body draft, stem angle and some adimensional coefficients. This information is then used to fair the hull surface, which must in turn fulfil more prerequisites (parameters like displaty cement, floatation area and related coefficients). The hull is defined by means of a B-spline surface, the fairing of which is ensured by allowing for all the imposed objective…
PRICE AS AN INTEGRATED MARKETING COMMUNICATION TOOL IN PROMOTING THE CONSUMPTION OF SUSTAINABLE PRODUCTS
2018
There are favourable conditions for the development of sustainable marketing in Latvia. In order to take advantage of this, businesses need to conduct market research on the need and demand for sustainable products and draw up a marketing strategy encompassing all the marketing mix elements serving the People, Planet, and Profit. Businesses need to create a well-thought approach, a sustainable product assortment and promotion and selling activities in line with sustainability conditions. The consumers of nowadays are very sensitive to any price changes, and businesses may use price changes as an IMC (integrated marketing communication) tool in communication with their consumers to help not …
THE INFLUENCE OF INTEGRATED MARKETING COMMUNICATIONS ON THE DEMAND OF SUSTAINABLE PRODUCTS AT LATVIAN FOOD RETAIL CHAINS
2018
Research background: There are a number of product-related tools subject to regulation by state authorities and controlled by subordinate authorities. From the viewpoint of sustainable development, novelties in the legislation, government regulations and other regulatory enactments would enable the state to not only enhance the assortment of sustainable products at food retail chains, but also to raise the awareness of consumers, thus also triggering changes in demand for sustainable (ecological, environment-friendly, high-quality) products. Consumers lack information on the characteristics of the products purchased; they are not knowledgeable about the nutritional value, packaging, raw mat…
Cyber Situational Awareness in Critical Infrastructure Protection
2020
The European Union promotes collaboration between authorities and the private sector, and the providers of the most critical services to society face security related obligations. In this paper, critical infrastructure is seen as a system of systems that can be subject to cyber-attacks and other disturbances. Situational awareness (SA) enhances preparations for and decision-making during assessed and unforeseen disruptive incidents, and promoting Cyber effective situational awareness (CSA) requires information sharing between the different interest groups. This research is constructive in nature, where innovative constructions developed as solutions for domain-specific real world problem…
CFD simulation of a membrane distillation module channel
2009
The interest towards the use of membrane distillation (MD) processes for seawater desalination has been rising recently due to the ease of coupling MD with waste and/or solar thermal energy. Notwithstanding the flexibility of the process and its potential for further developments in membrane performances, one of the main drawbacks is the thermal efficiency reduction caused by temperature polarization. Because of such phenomenon, only a small amount of the driving force potentially available for the separation process, i.e. the temperature difference between evaporating and condensing fluids, is actually used for the separation. In order to reduce temperature polarization a study on the effe…
Fractional viscoelastic behaviour under stochastic temperature process
2018
Abstract This paper deals with the mechanical behaviour of a linear viscoelastic material modelled by a fractional Maxwell model and subject to a Gaussian stochastic temperature process. Two methods are introduced to evaluate the response in terms of strain of a material under a deterministic stress and subjected to a varying temperature. In the first approach the response is determined making the material parameters change at each time step, due to the temperature variation. The second method, takes advantage of the Time–Temperature Superposition Principle to lighten the calculations. In this regard, a stochastic characterisation for the Time–Temperature Superposition Principle method is p…
Extended Environmental Contour Methods for Long-Term Extreme Response Analysis of Offshore Wind Turbines1
2020
Abstract Environmental contour method is an efficient method for predicting the long-term extreme response of offshore structures. The traditional environmental contour is obtained using the joint distribution of mean wind speed, significant wave height, and spectral peak period. To improve the accuracy of traditional environmental contour method, a modified method was proposed considering the non-monotonic aerodynamic behavior of offshore wind turbines. Still, the modified method assumes constant wind turbulence intensity. In this paper, we extend the existing environmental contour methods by considering the wind turbulence intensity as a stochastic variable. The 50-year extreme responses …
A 4500 year record of palaeomagnetic secular variation and relative palaeointensity from the Tyrrhenian Sea
2020
A marine sediment core from the western Mediterranean provides a newhigh-resolution 4,500-year record of palaeomagnetic secular variation and relativepalaeointensity. In 2013, the 7.1-metre C5 core was recovered from the TyrrhenianSea as part of the NextData climate data project. The coring site, 15 km offshorefrom the Volturno river mouth, is well-located to record combined marine andterrestrial palaeoclimatic influences, and the fine-grained, rapidly deposited sedimentsare effective palaeomagnetic recorders. We investigate the palaeomagnetic field direction and strength recorded in the core, which provide a valuable high-resolution recordof Holocene geomagnetic variation in the area. Usin…
Nonlinear air dynamics of a surface effect ship in small-amplitude waves
2022
In many existing works, the seakeeping motions and air dynamics of a surface effect ship (SES) were assumed to be linear under small-amplitude waves (wave amplitude to wave length ratio ≤ 5%) to enhance the computational efficiency. However, according to SES model test results, it was found that even in small-amplitude waves, the fluctuating air cushion pressure shows significantly nonlinear effects. To precisely reveal this distinctive feature, the origin of nonlinearity was carefully investigated and the air leakage was considered as the main source of nonlinearity based on mathematical analysis in this paper. The reason is that the variance of clearance height under seals is comparable t…
Analysis of spar and semi-submersible floating wind concepts with respect to human exposure to motion during maintenance operations
2022
Floating offshore wind turbines (FOWTs) are expected to experience onsite maintenances and inspections during their lifetimes. To carry out offshore maintenance activities, a crew will be transferred to an FOWT and spend several hours on board. A challenge may arise if the motions of a floating platform affect the crew's comfort level and further jeopardise their work performance or even health. To address this challenge, this paper analyses the motion characteristics and dynamic properties of a spar and two semi-submersible FOWTs, all exhibiting very different motion characteristics. The impact of the platform motions and accelerations on the workability of the FOWTs are investigated. We c…