Abstract: According to the International Maritime Organisation, oil tankers transport around 2.9 billion tonnes of crude oil and petroleum products by sea each year worldwide. Most of the time, oil is transported safely and quietly. However, the development of the transport activity is not free from risks that threaten the success of the navigation, endangering the ship, the oil cargo and, of course, the environment. This article studies, analyses, systematises and understands how the «unseaworthiness» of the ship is a prerequisite that maximises the probability of the occurrence of an environmental catastrophe due to the spillage or dumping of oil at sea. For this purpose, it is determined what is seaworthiness, the factors on which the concept is based; the consequences of the absence, lack of suitability, incompetence or lack of completeness are analysed which, if present both in a structural and naval technical aspect, as well as in the surveillance and control exercised by the tanker owner over the crew and other dependents, could ensure and prevent the occurrence of risks that may be an efficient cause for the spill or dumping of oil at sea.

Resumen: Según la Organización Marítima Internacional, los buques petroleros transportan alrededor de 2.900 millones de toneladas de petróleo crudo y productos derivados del petróleo por mar cada año en todo el mundo. La mayor parte del tiempo, los hidrocarburos se transportan de manera segura y tranquila. No obstante, el desarrollo de la actividad transportadora no está exenta de riesgos que amenacen el éxito de la navegación, poniendo en peligro al buque, la carga de petróleo, y como no al medio ambiente. El presente artículo estudia, analiza, sistematiza y comprende cómo la falta de navegabilidad o «innavegabilidad» del barco, constituye un presupuesto que maximiza la probabilidad de advenimiento de una catástrofe ambiental, por el derrame o vertimiento de hidrocarburos en el mar. Para ello, se determina qué es la navegabilidad, los factores en que se erige el concepto; se analizan las consecuencias de la ausencia, carencia de idoneidad, incompetencia o falta de completitud que, de estar presentes tanto en un aspecto estructural y de técnica naval, como en la vigilancia y control que ejerce el armador del buque petrolero, sobre la tripulación y demás dependientes, podrían asegurar y prevenir la ocurrencia de los riesgos que pueden ser causa eficiente para el derrame o vertimiento de hidrocarburos en el mar.

Resumen El objetivo de este artículo es aportar algunas ideas, argumentos y reflexiones al debate acerca de la conveniencia de mantener la reserva legal de cabotaje de carga marítima para las naves de bandera chilena. La metodología empleada consiste en el análisis de la reserva legal, su origen, críticas, defensas, función y efectos en la realidad socio económica nacional prevaleciente, así como su comparación con la situación imperante en algunos países extranjeros. Como resultado de este trabajo, hemos arribado a la conclusión de la conveniencia de mantener la reserva legal de cabotaje marítimo de carga para las naves de bandera chilena, por diversas razones económicas, sociales, geopolíticas y jurídicas. En especial, mientras no se proponga un mecanismo para asimilar las condiciones legales, laborales, tributarias y operacionales que rodean la actividad de los armadores nacionales, con las de sus competidores de pabellón extranjero, otorgando a aquéllos condiciones de competitividad equivalentes con las existentes en el mercado naviero internacional.

Abstract The purpose of this paper is to contribute with some ideas, arguments and reflections to the discussion about the convenience of the survival of the legal reservation of the maritime cargo cabotage for Chilean flagged vessels. The methodology employed is the analysis of the legal reservation, its origin, criticisms, defenses, function and effects in the prevailing national social and economic situation, as well as its comparison with the existing situation in some foreign countries. As a result of this work, we have reached the conclusion of the convenience of maintaining the legal reservation of the maritime cargo cabotage for Chilean flagged vessels, due to many economic, social, geopolitical and legal reasons. In particular, as long as no mechanism is proposed in order to equate the legal, labor, tax and operational conditions that surround the operation of the national shipping lines, to those of its competing foreign flagged vessels, providing the former conditions of competition that are equivalent to those prevailing in the international shipping market for the latter.

ABSTRACT This study encompasses the analysis of oil spills occurred in the Gulf of Morrosquillo during the loading procedures of oil tankers in the Coveñas maritime Terminal, by means of numerical simulation experiments of the trajectories and weathering processes of oil spilled, which occurred under specific wind, waves, and ocean currents conditions. A three-dimensional (3D) modelling system, OpenOil, which is part of the open-source OpenDrift trajectory framework was used to simulate two contingencies occurred in July and August 2014. During each event, different volumes of Vasconia crude oil spilled on the sea surface were simulated. The resulting slicks were subject to wind drift, Stokes drift from wave forcing, and ocean currents transporting the oil spilled towards the coast. Oil weathering effects (evaporation, emulsification, and biodegradation) are included in the analysis. To calculate weathering of the oil, OpenOil interfaces with the latest version of the open source ADIOS oil library. It should be noted that meteorological and ocean conditions contribute to the oil pathways that in both periods forced the oil slick towards the central coast of the Gulf. The wind speed is an important factor contributing to the rapid evaporation rates of the oil spilled in the warm waters of the Caribbean Sea; hence, allowing a gradual increase of the water fraction, which could lead to the formation of tar balls found in the affected coasts in the areas simulated by the model. The implementation of OpenOil to predict the oil fate and weathering processes in the Colombian basin prove to be a valuable tool that should be used in this maritime terminal to improve planning and preparedness in case of an oil spill. The simulations could be enhanced with higher resolution databases.

RESUMEN Este estudio comprende el análisis de los derrames de hidrocarburos ocurridos en el Golfo de Morrosquillo durante los procedimientos de carga de buques petroleros en el Terminal Marítimo de Coveñas, mediante la simulación numérica de las trayectorias y procesos de envejecimiento del crudo derramado, los cuales ocurrieron bajo condiciones específicas de viento, oleaje y corrientes oceánicas. Se utilizó un sistema de modelado tridimensional (3D), OpenOil, que forma parte del OpenDrift, de código abierto, para simular dos contingencias que ocurrieron en julio y agosto de 2014. Durante cada evento se simularon diferentes volúmenes de crudo Vasconia derramado en la superficie del mar. Las manchas resultantes están sujetas a la deriva del viento, la deriva de Stokes por la fuerza de las olas y las corrientes oceánicas que transportan el crudo derramado hacia la costa. Se incluye en el análisis los efectos del intemperismo o meteorización en la calidad del crudo (evaporación, emulsificación y biodegradación). Para calcular el envejecimiento del petróleo, OpenOil interactúa con la última versión de la biblioteca de hidrocarburos ADIOS de código abierto. Se encontró que las condiciones meteorológicas y oceánicas contribuyen con el comportamiento de la mancha de crudo, que durante estos dos períodos forzaron la trayectoria de la mancha hacia la costa central del Golfo. La velocidad del viento es un factor importante que contribuye a las rápidas tasas de evaporación del petróleo derramado en las cálidas aguas del mar Caribe, lo que permite un aumento gradual de la fracción de agua, que podría conducir a la formación de bolas de alquitrán que se encontraron en las costas afectadas en las áreas que fueron simuladas por el modelo. La implementación del OpenOil para predecir el destino del petróleo y los procesos de envejecimiento en la cuenca colombiana resulta ser una valiosa herramienta que debe utilizarse en esta terminal marítima para mejorar la planificación y preparación en caso de un derrame de petróleo en el Golfo de Morrosquillo. Las simulaciones obtenidas podrían mejorarse con el uso de bases de datos de más alta resolución.

Abstract: It is estimated that ships transport about 80 % of world trade; in other words, these are goods transfers carried out by maritime mode. The maritime sale is a kind of sale and is understood as a form of distance commercial exchange. Originally, its dynamism has been closely related to the fluctuations inherent to international trade because of market opening policies or the adoption of protectionist measures. It is a known fact that in maritime sales the confluence of at least four types of contracts occurs: The sales contract, the transport contract, the documentary credit contract and the cargo insurance contract. This investigation analyzes the dynamics of maritime sales with emphasis on the main contract, which is the international sales contract, and approaches the state of the art in Peru.

Resumen Se estima que cerca del 80 % del comercio mundial, se transporta por medio de buques; es decir, se trata de traslados de mercancías que se realizan por el modo marítimo. La venta marítima, es una especie de compraventa y se entiende como una forma de intercambio comercial a distancia. Desde sus orígenes, su dinamismo guarda estrecha relación con las fluctuaciones propias del comercio internacional como consecuencia de políticas de apertura de los mercados o la adopción de medidas proteccionistas. Es conocido que en las ventas marítimas se presenta la confluencia de al menos cuatro contratos, a saber: el contrato de compraventa, el contrato de transporte, el contrato de crédito documentario y el contrato de seguro de la carga. Esta investigación analiza la dinámica de las ventas marítimas con énfasis en el contrato principal, que es el de compraventa internacional, y se aproxima al estado de la cuestión en el Perú.

RESUMO Os sistemas de drenagem urbana podem representar fontes de aporte de poluentes aos corpos receptores aos quais se destinam. Diante disso, o presente trabalho teve como objetivo propor uma ferramenta para modelagem do sistema de drenagem urbana da bacia da Vertente Marítima de Fortaleza, Ceará, visando à avaliação das cargas bacteriológicas. Para esse fim, foi selecionado o stormwater management model (SWMM) para as simulações hidrológicas e hidráulicas; propôs-se uma metodologia para o cálculo das cargas bacteriológicas por meio da estimativa da carga difusa [CD] (NMP. dia-1.ha-1) e para a correlação desta com uma série de variáveis hidroambientais; e analisaram-se cenários para diferentes condições de precipitação pluviométrica, coleta de esgoto e resíduos sólidos dispostos inadequadamente (RSDI). Os resultados mostraram que o SWMM oferece respostas representativas e que o período chuvoso é responsável pelo maior aporte da carga bacteriológica à orla. Em relação ao modelo preditivo, foi ajustada uma função de potência de segunda ordem correlacionando CD com a precipitação média mensal (mm.dia-1) para as três sub-bacias analisadas. Posteriormente, os coeficientes das equações encontradas foram correlacionados ao indicador RSDI (kg.dia-1), obtendo-se um ajuste logarítmico (R2 = 0,99), com o qual é possível gerar uma equação de estimativa de CD para qualquer sub-bacia da Vertente Marítima. A análise dos cenários mostrou haver aumento significativo da carga em precipitações extremas (2 vezes) e diminuição considerável com a elevação da fração da população interligada à rede de esgoto, bem como diminuição da produção de RSDI (0,28 e 0,38 vezes do valor inicial nos Riachos Jacarecanga e Maceió, respectivamente).

ABSTRACT Urban drainage systems can represent sources of pollutants input to the receiving bodies for which they are intended. Therefore, the present work aims to propose a tool for modeling the urban drainage system of the Vertente Marítima basin of Fortaleza, Ceará, aiming at the evaluation of bacteriological loads. For this purpose, the Stormwater Management Model (SWMM) was selected for the hydrological and hydraulic simulations; a methodology for the calculation of bacteriological loads was proposed by estimating the diffuse load [DL] (MPN, day-1.ha-1) and its correlation with a series of hydro-environmental variables and scenarios for different pluviometry precipitation conditions were analyzed, as well as sewage collection and inadequately disposed solid waste (IDSW). The results show that SWMM gives representative results and that the rainy season is responsible for the greater contribution of the bacteriological load to the seafront. Regarding the predictive model, a second-order potential function was adjusted by correlating DL with the average monthly precipitation (mm.day-1) for the three sub-basins analyzed. Subsequently, the coefficients of the equations found were correlated to IDSW (kg.day-1), obtaining a logarithmic adjustment (R2 = 0.99), with which it is possible to obtain a DL estimation equation for any sub-basin of Vertente Marítima. An analysis of the scenarios showed a significant increase of the load in extreme precipitations (twice) and a considerable decrease with the increase of the fraction of the population connected to the sewage network and the decrease of IDSW production (0.28 and 0.38 times the initial value in the Jacarecanga and Maceió Stream, respectively).

Between the seventeenth and nineteenth centuries, the North of Chile became a dynamic center of production and export of wine brandy called "pisco". The spirits market was intended to Potosi, both by sea and by land, by regular freight service offered by the carriers. Thus arose the path of brandy, which helped to establish close economic, social and cultural links between the cities, towns and rural areas of current Chile, Argentina and Bolivia. So the basis for the development of the Appellation of Origin Pisco bounded burst in 1931.

Entre los siglos XVII y XIX el Norte Chico de Chile se convirtió en un dinámico polo de producción y exportación de aguardientes. El aguardiente se destinaba al mercado de Potosí, tanto por vía marítima como por vía terrestre, gracias al servicio regular de transporte de carga que ofrecían los arrieros. Surgió así la ruta del aguardiente, que contribuyó a establecer estrechos lazos económicos, sociales y culturales entre las ciudades, villas y localidades rurales de las actuales Chile, Argentina y Bolivia. Así se echaron las bases para el desarrollo de la Denominación de Origen Pisco, delimitada en 1931.

This paper uses the technique of discrete event simulation as methodology for decision support in a complex problem with multiple variables; the objective is to model the logistics operations involved in the maritime exportation of commodities in the presentations of bulk and bags from twelve producers until the seaport. The simulation allows analyzing the sensitivity of the key parameters and system variables in order to define different models of planning offices. Results showed that it is possible to reduce the inventory and maintenance costs, as well as improving the service performance indicators and consequently increasing the resources utilization rate.

El presente trabajo utiliza la técnica de simulación de eventos discretos como metodología de apoyo a la decisión en un problema complejo con múltiples variables; el objetivo es modelar las operaciones logísticas involucradas en la exportación marítima de commodities en las presentaciones de carga suelta y granel desde doce empresas productoras hasta el puerto marítimo. La simulación permite analizar la sensibilidad de los principales parámetros y variables del sistema, con el fin de definir diferentes modelos de planeación de despachos. Los escenarios muestran que es posible obtener una reducción de los inventarios y de los costos de mantenimiento, así como también mejorar los indicadores de servicio y como consecuencia aumentar la tasa de utilización de los recursos.

O objetivo do artigo é apresentar o processo de decisão em grupo realizado junto a executivos de uma agência marítima com operação no Sul do Brasil, no qual a técnica Processo de Análise Hierárquica (AHP) foi utilizada como suporte. A decisão envolveu a priorização de confirmações de reservas de embarque de cargas de exportação em um determinado instante, em situação de escassez - falta de contêineres vazios ou espaços nos navios disponíveis. O contexto do estudo foi o porto de Rio Grande, no Estado do Rio Grande do Sul. A escolha da organização e do porto foi feita por conveniência. Utilizou-se a metodologia de resolução de problemas da pesquisa operacional (formulação do problema, construção do modelo, solução do modelo, teste do modelo e avaliação da solução e avaliação final) para gerar um modelo matemático para auxiliar os decisores na priorização de reservas de embarque de cargas. Dados secundários foram coletados da empresa estudada. Foram feitas reuniões para geração do modelo com a equipe comercial da empresa, composta por quatro funcionários e um gerente. O método mostrou-se apropriado para expandir a mente dos decisores, ao oportunizar a incorporação no processo decisório de outros fatores, além da visão meramente financeira, considerando fatores gerenciais e organizacionais. A validação do processo pelo grupo de executivos incluiu uma apreciação da qualidade da decisão tomada. Os executivos envolvidos foram unânimes ao afirmarem sua satisfação com os resultados obtidos a partir da utilização da técnica.

The aims of this article is to present the group decision-making process carried out with executives from a shipping agency operating in the south of Brazil, in which the Analytic Hierarchy Process (AHP) technique was used as support. The decision involved the prioritization of booking confirmations for the shipment of cargos for export at a particular moment in time, in a situation of scarcity - a lack of empty containers or space on the available vessels. The study context was the harbor of Rio Grande, in the State of Rio Grande do Sul. The choice of the organization and the harbor was done by convenience. It was used the methodology of problem solution of the operating research (problem formulation, model design, model solution, model testing and solution evaluation, and final evaluation) to generate a mathematical model for supporting decision makers on prioritizing booking confirmations for shipment of cargos. Secondary data were collected from the studied company. It was done meetings for generating the model with the commercial team of the company, composed by four employees and one manager. The method proved appropriate for broadening the mind of the decision makers as it facilitated the incorporation within the decision making process of other factors rather than the purely financial view, by taking into consideration managerial and organizational factors. The validation of the process by the group of executives included an assessment of the quality of the decision taken. The executives involved were unanimous in stating their satisfaction with the results obtained with the use of the technique.