230 research outputs found
The Need for Unification and Harmonization in a Maritime Licensing Standard for Recreational Craft
The objective of this document is to make clear the importance of simplifying the transit of pleasure boats and their skippers safely in the European territory with the foreseeable improvement of the functioning of the internal market. In many European countries recreational skippers are required to have specific training and experience in order to demonstrate their maritime competence. These licenses for navigation allow a recreational vessel to be skippered in each national territory. One of the main objectives of these qualifications is to reduce the number of accidents in recreational boating. Generally speaking, in the European Union, as regards the requirements for the management of pleasure craft, both private and professional, the requirements are very different depending on the member state
Crystallography and Nobel Prizes: On the 2011 Nobel Prize in Chemistry, awarded to Dan Shechtman
La cristal·lografia té una gran presència en els premis Nobel; així doncs, 48 guardonats
estan estretament vinculats a la cristal·lografia. El Premi Nobel de Química 2011
va ser concedit a Dan Shechtman pel descobriment dels quasicristalls. A part del mèrit
científic del descobriment, el Premi és un reconeixement al treball de Dan Shechtman, ja
que les seves idees van ser rebutjades inicialment per la comunitat científica internacional.
Finalment la raó es va imposar, amb el suport d'arguments que van venir per camins
insospitats i aparentment sense cap relació, com ara l'estudi dels mosaics presents en
edificacions àrabs i també del concepte de tessel·lació. També hi van contribuir conceptes
més pròpiament cristal·logràfics com les macles i les estructures modulades. L'any 1992
la Unió Internacional de Cristal·lografia va modificar la definició de cristall per tal d'incloure-hi els quasicristalls.Crystallography has a considerable presence among Nobel Prize laureates. Indeed,
48 of them have close links to crystallography. The 2011 Nobel Prize in Chemistry
was awarded to Dan Shechtman for his discovery of quasicrystals. In addition to the scientific
merit of the work, the Prize is a personal recognition of Dan Shechtman, whose ideas
were initially rejected by the international scientific community. Yet, reason prevailed in the
end, supported by arguments that arrived from seemingly unrelated directions, such as the
study of Arab building tiles and the mathematical concept of tessellation. Concepts of a
more crystallographic nature, such as twinned crystals and modulated and incommensurate
crystal structures, also played an important role. Finally, in 1992, the International
Union of Crystallography modified the definition of crystal to include quasicrystals
Salvamento marítimo
Libro basado en las ponencias presentadas en las I Jomadas de Tráfico y Salvamento Marítimo organizadas por la Asociación de Controladores de Tráfico Marítimo y la Facultad de Ciencias Náuticas de la Universidad de Cádiz. Casino de Tarifa, 24 de mayo de 2000
A software tool for monitoring legal minimum lenght of landings: Case study of a fishery in sourthern Spain
Herramienta de interés para el control y la gestión de pesqueríasThe regulation of minimum legal size(MLS) of catches is a tool widely applied in the management of fisheries resources, although the MLS does not always coincide with the length at first maturit(LFM). The optimization of this management tool requires a series of quality control in fish markets and transportation. A software application has been developed to make the control of the landings of several target species easier and faster. In order to test and make this tool operational,six species of commercial interest were selected: four species of fish hand two species of bivalves. It is proposed to estimate the proportion of illegal specimens in the studied lot from the proportion of illegal individuals found in the samples taken from this lot.The input data for the application are the minimum legal size(MLS) of the species and the total length(TL)of each specimen sampled. The out put data is a statistical summary of the percentage of specimens of size less than the legal minimum(TL<=MLS)within
different confidence intervals(90%,95% and 99%). The software developed will serve as a fast,efficient and easy to manage tool that allows inspectors to determine the degree of compliance on MLS control and to make a decision supported by statistical proof on fishing goods
La seguridad del transporte marítimo. Retos del siglo XXI
Esta obra analiza, en primer lugar, el marco histórico y normativo del transporte marítimo. A continuación, los elementos claves de la seguridad del buque, el factor humano, el comportamiento y los planes de contingencias ante emergencias marítimas y, por último, la contaminación operacional y accidental por buques. La seguridad marítima es hoy una herramienta fundamental de fiabilidad del sistema de transporte y, en definitiva, es una de las claves para el aseguramiento de la cadena de producción
Technical education of seafarers in Spain: an historical review
This review discusses the historical evolution of nautical education in Spain. In the Modern Age there are two distinct phases in the technical training of seafarers: Medieval guild, usually host under a religious patronage, formed as confraternities of tradesmen, a character maintained for the first two centuries of the West Indies Fleet; and a later stage, which we call institutional phase, coincident in time with the Age of Enlightenment. In the nineteenth century these teachings became competition to the Commerce Consulate, and finally, in the twentieth century Nautical schools are integrated within the Spanish universities as higher technical education.La presente revisión histórica aborda la evolución de las enseñanzas náuticas en España. En la Edad Moderna existen dos fases bien diferenciadas en la formación del marino: una de carácter gremial, acogida normalmente a un patronato religioso, al estilo de las enseñanzas de los oficios más técnicos, como así ocurría en la Edad Media, y que permanece durante los dos primeros siglos de la Carrera de Indias; y una posterior fase, que llamaremos institucional, coincidente en el tiempo con las reformas ilustradas. Ya en el siglo XIX se produce la incorporación de estas enseñanzas a los Consulados de Comercio, para finalizar en el siglo XX con la integración como enseñanzas técnicas superiores en el seno de las universidades españolas
Comparing Surgical and N95 Mask Use on Resting Oxygen Consumption in Healthy Young Adults
Face masks reduce the spread of COVID-19, but their impact on respiratory physiology largely remains unknown. While some studies found that exercising while wearing cloth or surgical face masks has no effect on performance or muscle oxygenation, studies have shown wearing surgical masks during high-intensity interval training (HIIT) and aerobic exercise had negative impacts on cardiopulmonary function. However, few studies examined changes in cardiorespiratory metabolism while wearing different types of face masks at rest. PURPOSE: To examine oxygen consumption (VO₂) and carbon dioxide ventilation (VCO₂) while wearing surgical and N95 masks at rest. METHODS: This study was IRB approved. Twenty-two subjects (age 24.6±2.94, 14 female), were recruited from a convenience sample and signed written consent. Subjects had no known history of respiratory/metabolic disease or claustrophobia. VO₂ (mL/kg/min) and VCO₂ (mL/min) were recorded using indirect calorimetry under a canopy. Subjects fasted overnight for a minimum of eight hours. Each subject’s first trial recorded baseline measurements without a face mask, then the order of their surgical and N95 mask trials was randomized. Each of the three trials were 15 minutes, with a rest between conditions. Comfort levels were measured after each condition using a Likert scale, and open-ended responses were recorded after testing. RESULTS: Repeated measures ANOVA with post hoc Bonferroni correction was used to analyze the mean values during the final 10 minutes of each trial. Both VO₂ and VCO₂ were significantly lower in the surgical mask condition when compared with no face mask (p=0.005, p=0.008, respectively), but were not significantly different in the N95 mask condition compared with no face mask (p=0.12, p=0.054, respectively). The majority (95.5%) of subjects reported being least comfortable wearing the N95 mask. CONCLUSION: VO₂ and VCO₂ at rest were significantly decreased when subjects wore surgical masks compared to no face masks, while N95 masks showed no significant difference. These findings suggest that in an acute setting, different types of face masks may have varied effects on oxygen consumption. Further research is needed to understand the impact of the prolonged use of face masks at rest
Transporte marítimo y medio ambiente
Francisco Piniella Corbacho es profesor del
departamento de Ciencias y Técnicas de la
Navegación de la Universidad de Cádiz, impartiendo docencia en la Facultad de Ciencias
Náuticas. En este libro realiza un estudio sincrético sobre la contaminación producida por el
transporte marítimo de sustancias nocivas al
medio; desde las claves básicas del problema
hasta las complejas técnicas de lucha y contención pasando por la normativa internacional y
los convenios que rigen en la actualida
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