10 research outputs found

    Evaluation of Paris MoU Maritime Inspections Using a STATIS Approach

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    Port state control inspections implemented under the Paris Memorandum of Understanding (MoU) have become known as one of the best instruments for maritime administrations in European Union (EU) Member States to ensure that the ships docked in their ports comply with all maritime safety requirements. This paper focuses on the analysis of all inspections made between 2013 and 2018 in the top ten EU ports incorporated in the Paris MoU (17,880 inspections). The methodology consists of a multivariate statistical information system (STATIS) analysis using the inspected ship's characteristics as explanatory variables. The variables used describe both the inspected ships (classification society, flag, age and gross tonnage) and the inspection (type of inspection and number of deficiencies), yielding a dataset with more than 600,000 elements in the data matrix. The most important results are that the classifications obtained match the performance lists published annually by the Paris MoU and the classification societies. Therefore, the approach is a potentially valid classification method and would then be useful to maritime authorities as an additional indicator of a ship's risk profile to decide inspection priorities and as a tool to measure the evolution in the risk profile of the flag over time.This research was funded by University of Cadiz

    A Clustering-Based Hybrid Support Vector Regression Model to Predict Container Volume at Seaport Sanitary Facilities

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    An accurate prediction of freight volume at the sanitary facilities of seaports is a key factor to improve planning operations and resource allocation. This study proposes a hybrid approach to forecast container volume at the sanitary facilities of a seaport. The methodology consists of a three-step procedure, combining the strengths of linear and non-linear models and the capability of a clustering technique. First, a self-organizing map (SOM) is used to decompose the time series into smaller clusters easier to predict. Second, a seasonal autoregressive integrated moving averages (SARIMA) model is applied in each cluster in order to obtain predicted values and residuals of each cluster. These values are finally used as inputs of a support vector regression (SVR) model together with the historical data of the cluster. The final prediction result integrates the prediction results of each cluster. The experimental results showed that the proposed model provided accurate prediction results and outperforms the rest of the models tested. The proposed model can be used as an automatic decision-making tool by seaport management due to its capacity to plan resources in advance, avoiding congestion and time delays

    Artificial Neural Networks, Sequence-to-Sequence LSTMs, and Exogenous Variables as Analytical Tools for NO2 (Air Pollution) Forecasting: A Case Study in the Bay of Algeciras (Spain)

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    This study aims to produce accurate predictions of the NO2 concentrations at a specific station of a monitoring network located in the Bay of Algeciras (Spain). Artificial neural networks (ANNs) and sequence-to-sequence long short-term memory networks (LSTMs) were used to create the forecasting models. Additionally, a new prediction method was proposed combining LSTMs using a rolling window scheme with a cross-validation procedure for time series (LSTM-CVT). Two different strategies were followed regarding the input variables: using NO2 from the station or employing NO2 and other pollutants data from any station of the network plus meteorological variables. The ANN and LSTM-CVT exogenous models used lagged datasets of different window sizes. Several feature ranking methods were used to select the top lagged variables and include them in the final exogenous datasets. Prediction horizons of t + 1, t + 4 and t + 8 were employed. The exogenous variables inclusion enhanced the model's performance, especially for t + 4 (rho approximate to 0.68 to rho approximate to 0.74) and t + 8 (rho approximate to 0.59 to rho approximate to 0.66). The proposed LSTM-CVT method delivered promising results as the best performing models per prediction horizon employed this new methodology. Additionally, per each parameter combination, it obtained lower error values than ANNs in 85% of the cases

    Ejercicios resueltos de programación en C.

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    Ayudar a la repoblación forestal, contribuir a la explosión demográfica, y dejar algún legajo, son algunas de las obligaciones que todo ser civilizado tiene para con este mundo. Sobre el primer deber, estoy seguro que los autores algo habrán plantado en algún sitio, aunque sea un jaramago. En relación con la segunda, lo del hijo, es sabido de uno de ellos, Pepe Galindo. De Pedro, por lo menos no consta. Algunos comparan la segunda de las obligaciones con la tercera. Hablan de un libro como si fuera un hijo del autor o autores. Si comparamos el libro, por ejemplo, con Patricia, la hija de Pepe, (con la necesaria e inestimable colaboración de su esposa), pierde el libro seguro. Un ángel rubio, mucho más importante que cualquier conjunto de reglas y símbolos que conforman un libro de un lenguaje de programación. Si alguien piensa que el C es más importante, es que no la conoce.211 págs

    Air pollution relevance analysis in the bay of Algeciras (Spain)

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    The aim of this work is to accomplish an in-depth analysis of the air pollution in the two main cities of the Bay of Algeciras (Spain). A large database of air pollutant concentrations and weather measurements were collected using a monitoring network installed throughout the region from the period of 2010-2015. The concentration parameters contain nitrogen dioxide (NO2), sulphur dioxide (SO2) and particulate matter (PM10). The analysis was developed in two monitoring stations (Algeciras and La Linea). The higher average concentration values were obtained in Algeciras for NO2 (28.850 mu g/m(3)) and SO2 (11.966 mu g/m(3)), and in La Linea for PM10 (30.745 mu g/m(3)). The analysis shows patterns that coincide with human activity. One of the goals of this work is to develop a useful virtual sensor capable of achieving a more robust monitoring network, which can be used, for instance, in the case of missing data. By means of trends analysis, groups of equivalent stations were determined, implying that the values of one station could be substituted for those in the equivalent station in case of failure (e.g., SO2 weekly trends in Algeciras and Los Barrios show equivalence). On the other hand, a calculation of relative risks was developed showing that relative humidity, wind speed and wind direction produce an increase in the risk of higher pollutant concentrations. Besides, obtained results showed that wind speed and wind direction are the most important variables in the distribution of particles. The results obtained may allow administrations or citizens to support decisions

    Prediction of container filling for the selective waste collection in Algeciras (Spain)

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    14th Conference on Transport Engineering: 6th – 8th July 2021The aim of this study is to create an intelligent system that improves the efficiency of garbage collection, (cardboard waste, in this particular case). The number of cardboard containers to be collected each day will be determined based on a prediction made on the filled volume recorded in each container. It will be reflected in the cost and fuel savings, reducing emissions and contributing to environmental sustainability. These results will allow planning the sequence of waste removal, which means the optimal collection route considering restrictive parameters such as the type of truck, the location of containers, collection times by zones, and the availability of working staff. A filling prediction system is proposed based on real historical data provided by the current waste collection company in Algeciras (ARCGISA). To achieve this objective, an intelligent system is designed using predictive analytics and several methods based on machine learning, modelling the collection system as a classification model, comparing the results from a statistical point of view (using sensitivity, specificity, etc.). The results obtained with the best-Tested method indicate an improvement average rate of 26% in sensitivity performance index and 67% in specificity performance index. Currently, waste collection is carried out without predictive analysis. The relevance of an efficient waste collection system is becoming increasingly important. Achieving optimal waste collection will result in improved service to citizens, cost savings for the administration, and significant environmental improvements. © 2021 Elsevier B.V.. All rights reserve

    Una comparativa entre redes neuronales artificiales y métodos clásicos para la predicción de la movilidad entre zonas de transporte.: Aplicación práctica en el Campo de Gibraltar, España

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    Traffic issues are more common every day due to the great technological development of humanity. Therefore, the control is essential to optimize infrastructure and public transport. To achieve this goal, it is necessary to make an estimate of the demand of the mobility. An alternative method, based on Artificial Neural Networks (ANNs), has been analyzed in this work comparing to traditional prediction techniques. The aim is to obtain an estimation procedure using simple, economical input variables which are easy to find. Unlike traditional models. These new models are able to perform a better fitting of input-output mapping. The results are encouraging and therefore the ability of ANNs is shown to estimate mobility between zones.Los problemas de tráfico son cada vez más frecuentes debido al gran desarrollo tecnológico de la humanidad siendo, además, esencial su control para optimizar la infraestructura y el transporte público. Para lograr este objetivo, es necesario hacer una estimación de la demanda de los viajeros. Un método alternativo basado en redes neuronales artificiales (RNAs) se analiza en este trabajo, en comparación con las técnicas de predicción tradicionales. El objetivo es obtener un procedimiento de estimación usando variables de entrada sencillas y económicas, que son fáciles de encontrar. A diferencia de los modelos tradicionales, el modelo alternativo funciona mejor con los datos de entrada utilizados, ajustando mejor los resultados esperados. Los resultados son altamente prometedores y por tanto se demuestra la capacidad de las redes neuronales artificiales para realizar una estimación de la movilidad entre zonas

    Metodología para la clasificación de los puertos mediante indicadores de explotación utilizando análisis de conglomerados

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    This article classifies Spanish ports using a number of indicators that characterize the port activity. These indicators are treated with statistical analysis tools. Cluster analysis has been chosen to perform groupings among the selected ports. A methodology that covers all phases of research: environment, characterization, data source, cluster analysis, results and analysis of results has been followed in this paper. The results show that the Spanish ports are correctly characterized by physical and exploitation indicators, and that cluster analysis is a valid and useful tool for the port environment.En este artículo se clasifican los puertos españoles utilizado una serie de indicadores que caracterizan la actividad portuaria. Estos indicadores se tratan con herramientas de análisis estadístico. Se ha elegido el análisis de conglomerados para realizar agrupamientos entre los puertos seleccionados. Para ello se ha seguido una metodología de trabajo que cubre todas las fases de la investigación: entorno, caracterización, fuente de datos, análisis de conglomerados, resultados y análisis de resultados. Los resultados obtenidos demuestran que los puertos españoles se pueden caracterizar correctamente por medio de indicadores físicosy de explotación, y que el análisis de conglomerados es una herramienta válida y útil para el entorno portuario

    Comparison of maritime transport influence of SO2 levels in Algeciras and Alcornocales Park (Spain)

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    Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de BurgosThe main aim of this work was to measure the influence of the volume of shipping over the Sulphur dioxide (SO2) concentration in the air pollution in two monitoring stations located at Algeciras city and Alcornocales Park developing the same analysis in these two locations. The target is to demonstrate the assumption that Algeciras is more affected by SO2 than Alcornocales Park which is 30 km far away from Algeciras Port. A multiple regression approach has been applied using wind data: wind direction (degrees) and wind speed (km/h) recorded in two weather stations, together with the volume of the gross tonnage per hour (GT/h) of vessels in the Bay of Algeciras to estimate SO2 concentration values in the two stations Algeciras and Alcornocales. The database contains records of hourly samples of these variables during the year 2019. Different artificial neural networks (ANNs) models were compared and the results showed that SO2 in Algeciras station could be better explained than the same pollutant in Alcornocales station. On the other hand, ANNs produced better results than linear models which means that nonlinear models fit best the data. A cross- validation procedure has been applied in order to assure the generalization capabilities of the tested models. The results showed that in Algeciras a more reliable estimation could be done reaching a correlation estimation between the model and the target (real) values of SO2. This fact highlights the major influence of maritime transport in the Bay of AlgecirasThis work is part of the research project RTI2018-098160-B-I00 supported by 'MICINN’ Programa Estatal de I+D+i Orientada a 'Los Retos de la Sociedad'. Data used in this work have been kindly provided by the Algeciras Port Authority and the Andalusian Regional Government

    Prediction of container filling for the selective waste collection in Algeciras (Spain)

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    Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de BurgosThe aim of this study is to create an intelligent system that improves the efficiency of garbage collection, (cardboard waste, in this particular case). The number of cardboard containers to be collected each day will be determined based on a prediction made on the filled volume recorded in each container. It will be reflected in the cost and fuel savings, reducing emissions and contributing to environmental sustainability. These results will allow planning the sequence of waste removal, which means the optimal collection route considering restrictive parameters such as the type of truck, the location of containers, collection times by zones, and the availability of working staff. A filling prediction system is proposed based on real historical data provided by the current waste collection company in Algeciras (ARCGISA). To achieve this objective, an intelligent system is designed using predictive analytics and several methods based on machine learning, modelling the collection system as a classification model, comparing the results from a statistical point of view (using sensitivity, specificity, etc.). The results obtained with the best-tested method indicate an improvement average rate of 26% in sensitivity performance index and 67% in specificity performance index. Currently, waste collection is carried out without predictive analysis. The relevance of an efficient waste collection system is becoming increasingly important. Achieving optimal waste collection will result in improved service to citizens, cost savings for the administration, and significant environmental improvements.This work is part of the research project RTI-2018-098160-B-I00 supported by 'MICINN. Programa Estatal de I+D+i Orientada a 'Los Retos de la Sociedad'. Data used in this work have been kindly provided by ARCGISA. Colaboration between ARCGISA and University of Cádiz was supported with Fundación del Campus Tecnológico de Algeciras (FCTA)
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