Topological analysis of powertrains for refuse-collecting vehicles based on real routes–Part I: Hybrid hydraulic powertrain

In this two-part paper, a topological analysis of powertrains for refuse-collecting vehicles (RCVs) based on the simulation of different architectures (internal combustion engine, hybrid electric, and hybrid hydraulic) on real routes is proposed. In this first part, a characterization of a standard route is performed, analyzing the average power consumption and the most frequent working points of an internal combustion engine (ICE) in real routes. This information is used to define alternative powertrain architectures. A hybrid hydraulic powertrain architecture is proposed and modelled. The proposed powertrain model is executed using two different control algorithms, with and without predictive strategies, with data obtained from real routes. A calculation engine (an algorithm which runs the vehicle models on real routes), is presented and used for simulations. This calculation engine has been specifically designed to analyze if the different alternative powertrain delivers the same performance of the original ICE. Finally, the overall performance of the different architectures and control strategies are summarized into a fuel and energy consumption table, which will be used in the second part of this paper to compare with the different architectures based on hybrid electric powertrain. The overall performance of the different architectures indicates that the use of a hybrid hydraulic powertrain with simple control laws can reduce the fuel consumption up to a 14 %.     

Factors affecting the environmental impact of pavement wear

Wear at the interface between flexible pavements and tires influences pavement life, pavement cycle costs, and tire consumption, and is a source of environmental harm. Wear-related processes evolve over time and are affected by a number of boundary conditions, such as interface fluids, water and fuels. We develop a model explaining and predicting mass losses in flexible pavements under carefully controlled conditions, and with estimation of the related environmental costs. We also employed an accelerated loading test. Under normal conditions, the environmental impact of pavement wear is not greatly influenced by mix type or volumetrics. Indeed, the presence of hazmat materials, traditional, dense mixes have an environmental impact that is appreciably lower than that of porous European mixes.     

Fatigue analysis of butt welded AH36 steel joints: Thermographic Method and design S–N curve

The traditional methods of fatigue assessment of welded joints have some limitations, and are extremely time consuming. In order to overcome these difficulties, the Thermographic Method (TM), based on thermographic analyses, has been applied to predict the fatigue behaviour of butt welded joints, made of AH36 steel, largely used in shipbuilding. Experimental tests have been carried out to assess the fatigue capability in terms of S–N curves and fatigue limits. The predictions of the fatigue capability obtained resorting to the Thermographic Method show a good agreement with those derived from the traditional procedure. Moreover, the fatigue design recommendations were compared to the experimental data in order to analyse the reliability of the codes.     

The Decline of the Artisanal Fisheries in Mediterranean Coastal Areas: The Case of Cap de Creus (Cape Creus)

This article examines the sociocultural, economic, and environmental causes of the decline of the artisanal fisheries in the rocky coast of Cape Creus (NW Mediterranean) over the past decades. The changes that have occurred over time have favored trawlers, purse-seiners, shellfish fisheries, and tourism activities, to the detriment of artisanal fisheries. This article shows that the establishment of a marine reserve in 1998 could not reverse the observed decline in the artisanal fisheries. This raises the necessity of implementing a fishery management plan integrated into a coastal management plan, which should accompany the habitat protection. These plans could assist in the maintenance and the sustainable development of the artisanal fishing sector in Cape Creus as well as in other Mediterranean coastal areas where artisanal fisheries are also declining.     

Topological analysis of powertrains for refuse-collecting vehicles based on real routes–Part II: Hybrid electric powertrain

In this two-part paper, a topological analysis of powertrains for refuse-collecting vehicles (RCVs) based on simulation of different architectures (internal combustion engine, hybrid electric, and hybrid hydraulic) on real routes is proposed. In this second part, three different hybrid electric powertrain architectures are proposed and modeled. These architectures are based on the use of fuel cells, ultracapacitors, and batteries. A calculation engine, which is specifically designed to estimate energy consumption, respecting the original performance as the original internal combustion engine (ICE), is presented and used for simulations and component sizing. Finally, the overall performance of the different architectures (hybrid hydraulic, taken from the first paper part, and hybrid electric, estimated in this second part) and control strategies are summarized in a fuel and energy consumption table. Based on this table, an analysis of the different architecture performance results is carried out. From this analysis, a technological evolution of these vehicles in the medium- and long terms is proposed.     

A hazard-based approach to modelling the effects of online shopping on intershopping duration

Despite growing prevalence of online shopping, its impacts on mobility are poorly understood. This partially results from the lack of sufficiently detailed data. In this paper we address this gap using consumer panel data, a new dataset for this context. We analyse one year long longitudinal grocery shopping purchase data from London shoppers to investigate the effects of online shopping on overall shopping activity patterns and personal trips. We characterise the temporal structure of shopping demand by means of the duration between shopping episodes using hazard-based duration models. These models have been used to study inter-shopping spells for traditional shopping in the literature, however effects of online shopping were not considered. Here, we differentiate between shopping events and shopping trips. The former refers to all types of shopping activity including both online and in-store, while the latter is restricted to physical shopping trips. Separate models were estimated for each and results suggest potential substitution effects between online and in-store in the context of grocery shopping. We find that having shopped online since the last shopping trip significantly reduces the likelihood of a physical shopping trip. We do not observe the same effect for inter-event durations. Hence, shopping online does not have a significant effect on overall shopping activity frequency, yet affects shopping trip rates. This is a key finding and suggests potential substitution between online shopping and physical trips to the store. Additional insights on which factors, including basket size and demographics, affect inter-shopping durations are also drawn.     

Integration of structural health monitoring in life-cycle performance assessment of ship structures under uncertainty

In this paper, an approach for integrating the data obtained from structural health monitoring (SHM) in the life-cycle performance assessment of ship structures under uncertainty is presented. Life-cycle performance of the ship structure is quantified in terms of the reliability with respect to first and ultimate failures and the system redundancy. The performance assessment of the structure is enhanced by incorporating prior design code-based knowledge and information obtained by SHM using Bayesian updating concepts. Advanced modeling techniques are used for the hull strength computations needed for the life-cycle performance analysis. SHM data obtained by testing a scaled model of a Joint High-speed Sealift Ship is used to update its life-cycle performance.     

The Strategy for Coastal Sustainability: A Spanish Initiative for ICZM

The Spanish Strategy for Coastal Sustainability (SCS) was an initiative aimed at implementing coastal interventions under the principles of Integrated Coastal Zone Management (ICZM) and improving the state of the coast at the Spanish national level. The SCS, promoted by the Spanish Ministry of the Environment, started as a broad national strategy in 2005 and was finally delivered as a coastal planning instrument at the regional level in late 2007, designed to address coastal policies within the Spanish maritime–terrestrial public domain (MTPD). The initiative was triggered by the increasing pressure on the coastal zone and its preparation was supported by different European initiatives, first of all the European Recommendation on ICZM (413/2002/EC), while taking into consideration the future requirements of the Mediterranean Protocol on ICZM of the Barcelona Convention, signed in February 2008. Technically, the preparation of the SCS included four steps: (i) a Stakeholder Identification and Engagement process, including a stocktaking of the laws and regulations, (ii) the design of a broad Strategic Framework for the Spanish coastal zone, including a set of specific objectives and the instruments for its implementation, (iii) the signature of cooperation agreements for ICZM between the central government and the regions, and (iv) a detailed Technical Diagnosis at the local scale, designed to address future coastal interventions in the maritime–terrestrial public domain and its areas of influence. This article aims to: (i) illustrate the triggering factors of the SCS, including the Spanish coastal issues, the administrative framework at the national level, and the European and international policies addressing coastal management and (ii) illustrate the approaches and methodologies used for the preparation of the SCS, reporting the most relevant quantitative results. The article concludes that the SCS gave a strong contribution in the construction of a base of knowledge for the coastal zone and to improve coastal management practices. Despite this, complex distributions of competences still undermine the implementation of strategic interventions. In this context, the future ratification of the ICZM Protocol of the Barcelona Convention represents an opportunity to use the SCS process results and improve coastal management practices and the state of the coast.