Search results for "Ocean Engineering"
showing 10 items of 404 documents
Integration of foreign trade and maritime transport statistics in Spain
2010
This article aims to contribute to improving maritime trade data by analysing the possibility of integrating in a single enlarged databank two different databases: the Spanish foreign trade and maritime transport datasets. The methodology adopted consisted of studying the primary sources providing data compiled in the foreign trade and maritime traffic databases, analysing the electronic processes used by informants and data collectors and examining the linkages between the different electronic messages involved. Once the links between the trade and sea transport documents and electronic messages were found, a solution for integrating both databases was envisaged. The main outcome is a new …
Stochastic dynamics of nonlinear systems with a fractional power-law nonlinear term: The fractional calculus approach
2011
Fractional power-law nonlinear drift arises in many applications of engineering interest, as in structures with nonlinear fluid viscous–elastic dampers. The probabilistic characterization of such structures under external Gaussian white noise excitation is still an open problem. This paper addresses the solution of such a nonlinear system providing the equation governing the evolution of the characteristic function, which involves the Riesz fractional operator. An efficient numerical procedure to handle the problem is also proposed.
Pseudo-force method for a stochastic analysis of nonlinear systems
1996
Nonlinear systems, driven by external white noise input processes and handled by means of pseudo-force theory, are transformed through simple coordinate transformation to quasi-linear systems. By means of Itô stochastic differential calculus for parametric processes, a finite hierarchy for the moment equations of these systems can be exactly obtained. Applications of this procedure to the first-order differential equation with cubic nonlinearity and to the Duffing oscillator show the versatility of the proposed method. The accuracy of the proposed procedure improves by making use of the classical equivalent linearization technique.
ASSESMENT OF TEMPERATURE POLARIZATION IN MEMBRANE DISTILLATION CHANNELS BY LIQUID CRYSTAL THERMOGRAPHY
2014
AbstractThe measurement of local temperature distributions within a membrane distillation (MD) channel is a crucial step for the optimization of the channel and spacer geometry. This information allows the estimation of temperature polarization phenomena, which can dramatically influence the thermal efficiency of the process and the optimal choice of the geometric configuration (net spacer features, channel size, etc.). In the present work, a recently presented experimental technique, based on the use of thermochromic liquid crystals and digital image analysis, has been employed in order to assess the temperature polarization phenomena. The local heat transfer coefficient distribution on th…
ONLINE RECOMMENDATION SYSTEMS’ USAGE BY COMPANIES IN BALTIC COUNTRIES
2017
Global retailers are using sophisticated online recommendation systems (ORS) which enhance customers' loyalty towards the specific site. Online markets in Baltic countries are growing fast, but Baltic e-commerce sites are not using a wide enough range of eWOM tools. The aim of this paper is – to evaluate how eWOM through ORS is perceived and used by digital marketing specialists and e-commerce players in the Baltics. Research methods used were: literature analysis on ORS’s influence on consumer purchase decisions, and an expert survey and monitoring study. The research results revealed major barriers for advanced ORS usage in the Baltics, as they discovered a gap between experts' opinion an…
Estudiando la importancia de las mujeres maestras del Paraguay desde la educación artística
2020
El proyecto Mujeres Maestras es un homenaje a las docentes. Es una investigación educativa y artística que tiene como objetivo abordar la identidad de las mujeres que se dedican a la enseñanza. Utilizamos una metodología plural que combina estudios de caso, narraciones personales y artography. Se trata de un trabajo cualitativo y artístico. El proyecto busca unir intereses entre la universidad, los centros educativos y los museos. En Mujeres Maestras del Paraguay se destacan las diferencias experimentadas por las docentes en las escuelas públicas y privadas, aunque los resultados artísticos de la propuesta han generado intersecciones entre ambas realidades. Particularidades como el uso del …
Exploring the relationships between maritime connectivity, international trade and domestic production
2020
The objective of this paper is to simultaneously analyse the complex relationships between bilateral maritime connectivity, bilateral trade and domestic production as measured by gross domestic pro...
Moving mass over a viscoelastic system: asymptotic behaviours and insights into nonlinear dynamics
2023
AbstractMoving masses are of interest in many applications of structural dynamics, soliciting in the last decades a vast debate in the scientific literature. However, despite the attention devoted to the subject, to the best of the authors’ knowledge, there is a lack of analysis about the fate of a movable mass when it rolls or slips with friction on a structure. With the aim of elucidating the dynamics of the simplest paradigm of this system and to investigate its asymptotic response, we make reference to a two-degree-of-freedom model made of an elastically vibrating carriage surmounted by a spherical mass, facing the problem both theoretically and experimentally. In case of linear systems…
Mediterranean Coastal Lagoons Review: Sites to Visit before Disappearance
2022
Coastal lagoons are an established priority habitat in the European environment because of the biological communities that inhabit them. Their origin is related to the transport of sediments from a nearby river or the movement of sands by the marine currents that produce the closure of a gulf. Therefore, they are recent geological formations, which also disappear quickly if environmental conditions change. The 37 coastal lagoons with a surface area greater than 10 km2 located in the Mediterranean basin have been identified. Fishing has been the traditional use of these lagoons, in addition to their use as a navigation harbor when they are open to the sea. Pollution, quality problems and the…
INTEGRATION IN LATVIA: FLOWS AND EBBS IN NATIONAL AND EUROPEAN CONTEXT
2016
Russian-speaking communities in the member states of the European Union (EU), especially the Baltic States and Germany, have earned special attention, in recent years, as subjects of important integration policies, on one hand, and the main targets of Russia’s propagandist efforts, on the other. Because a significant part of Russian-speaking communities accepted these efforts, questions were raised concerning the effectiveness of previous integration policies to strengthen the national identity and invoke a feeling of political togetherness. Thus the factors fostering and triggering integration and the relations between civic and ethnocultural components of integration are of wide interest.…