An advanced solution for efficient logistics management at both company and network level

This paper proposes an advanced solution for efficient logistics management in urban areas based on a unified scheme able to address both static and dynamic decision making at a company and network level. The proposed solution generates the most efficient urban distribution plan utilizing an evolutionary metaheuristic approach and a backpressure framework that provide competitive scheduling and routing decisions. An empirical study based on real data is conducted assessing the performance of the proposed advanced solution and the reported results of the evaluation experiments demonstrate its generality and robustness.     

A Step Zero Analysis of the Galapagos Marine Reserve

Contrary to common perceptions, the creation of protected areas does not start when they are officially declared but generally follows a long process. For instance, the Galapagos Marine Reserve (GMR) was not “born” when it was formally announced on March 18^th 1998, but several decades before that. Through document analysis and key informant interviews, we applied the “step zero” approach to examine what happened prior to the implementation of the GMR. This study reveals that the GMR did not arise from a social and political vacuum; rather, events took place in the distant past, even centuries ago, influenced the reserve's creation and current status. Its establishment was driven by complex geopolitical, economic, social, and environmental factors from both within and outside Galapagos. Additionally, the process of creating the GMR was convoluted, marked by hidden interests and conflictive political agendas that triggered controversies between users. The making of the GMR was also influenced by the interest in promoting “nature-based” tourism, and the regulations that followed had disadvantaged small-scale fishers. This knowledge about the reserve's pre-implementation phase enables a broader understanding of the current challenges facing the performance of the GMR and points to possible governance interventions needed to enhance its sustainability.     

Advancing Knowledge for Use in Coastal and Estuarine Management: Competitive Research in the National Estuarine Research Reserve System

Decades of research has generated new scientific understanding and technologies aimed at better managing environmental change in estuarine and coastal regions. Yet many across the communities of coastal and estuarine research, management, and funding believe that progress has been too slow in applying this research in practice. This essay reviews how the National Estuarine Research Reserve System’s funding program evolved over the past two decades to improve how researchers and users of research work together to increase the uptake of science to achieve resource management and conservation goals. Incremental innovation in the design of the NERRS funding program enabled more intensive and multiway engagement between funders, researchers, and users, which created new pathways for applying science in practice. Furthermore, these interactions stimulate reflection and adaptation within each separate institutional setting, supporting changes that may science to better support environmental problem solving.     

New appraisal values of travel time saving and reliability in Great Britain

Transportation - This paper provides an overview of the study ‘Provision of market research for value of time savings and reliability’ undertaken by the Arup/ITS Leeds/Accent consortium...     

The acceptability of road pricing in Vienna: the preference patterns of car drivers

The acceptability of road pricing has attracted considerable attention among researchers over the last decade, as is evident in the amount of literature about transport and environmental economics. The general conclusion from these studies has been that there is low acceptability for road pricing among car users. In this paper, we add more knowledge to the existing literature by conducting an acceptability study of road pricing in Vienna, where such a study has never been conducted before. We used a replication study approach where a previous approach used in the EU research project AFFORD (acceptability of fiscal and financial measures and organisational requirements for demand management) was replicated for Vienna and further supplemented with a conjoint analysis. In order to examining whether the Vienna study confirms previous findings. We investigated the acceptability of two concrete policy packages factors influencing this acceptability, and preference patterns that can be used in designing a road pricing policy for Vienna. The survey reveals a higher acceptability if road pricing schemes lead to perceived personal benefits. According to the multivariate analyses, the “personal outcome expectations”, “social norm” and “perceived effectiveness” variables account for more than 50 % of the criterion variance and therefore these are the most influential factors. Road pricing schemes can be an effective transport management instrument for a city particularly if they are associated with direct investment in public transport and public infrastructure. Thus, personal benefits can be perceived more easily and direct effects can be expected.     

A method for extracting key performance indicators from maritime safety management norms

The maritime transportation industry currently employs several mandatory and non-mandatory norms of organizational safety management. These safety norms are commonly included in integrated maritime safety management systems, which aim at developing, monitoring, controlling and improving the safety of all related shipping operations. These systems are typically evaluated by following key performance indicators, which enable defined measures for various safety management components. However, the identification of indicators addressing safety management requirements constitutes a complex and generally unsystematic process for safety managers in the maritime industry. This article proposes a new method to assess the guidelines available in maritime safety management norms. The proposed method is applied to assess the content of two maritime safety management norms. The aim of this assessment is to identify a set of maritime safety management indicators that can systematically measure the most relevant components of maritime safety management. The application of this method resulted in the identification of 53 key performance indicators for monitoring and reviewing 23 identified safety management components that are commonly integrated into the functioning of maritime safety management systems. The method proposed provides guidance to accurately capture the actual aim and function of the key performance indicators. Furthermore, the indicators and safety components obtained with this method can be adopted as the basis for a safety management system and/or for the analysis of a safety management system already established in the industry.     

Krill behaviour as recorded by acoustic doppler current profilers in the Gullmarsfjord

Vertical distribution of sound scattering layers were observed using bottom deployed acoustic doppler current profilers (ADCP) during early spring of 1996 and autumn of 1997 in the Gullmarsfjord on the Swedish west coast. Variations in relative backscatter were interpreted in relation to horizontal water velocities, oxygen saturation as well as differences in the light, salinity and temperature regimes. Net catches revealed that much of the backscatter below 20-m depth was associated with the presence of krill, principally Meganyctiphanes norvegica.Horizontal currents seemed to influence the migration and distribution of krill, which showed weak vertical migration patterns with low abundance during periods of strong intermediate in- and outflows, while during periods with weaker currents, a more regular diel migration occurred. Horizontal water velocities >5 cm s⁻¹ seemed to have the potential to decrease the peak in the backscatter profile. Mean vertical migration rates of krill was 1 cm s⁻¹, while maximum vertical migration rates were estimated to be 2.5–3 cm s⁻¹. The range of the vertical migration was different in 1997 due to severe oxygen deficiency in the bottom water, which prevented the krill from descending >80 m. The commencement of vertical migration correlated closely to the seasonal light conditions. The descent was immediately triggered by sunrise, while ascent occurred with a delay of about 1 h at sunset.     

On the use of “average delay” as a measure of train reliability

We investigate how passengers on long-distance trains value unexpected delays relative to scheduled travel time and travel cost. For scheduled services with high reliability and long headways, the value of delays is most commonly assumed to be proportional to the average delay. By exploring how the valuation of train delays depends on delay risk and delay length, using three different stated choice data sets, we find that the “average delay” approach does not hold: the disutility increases slower than linearly in the delay risk. This means that using the average delay as a performance indicator, a guide for operations planning or for investment appraisal will underestimate the value of small risks of long delays relative to large risks for short delays. It also means that estimated valuations of “average delay” will depend on the delay risk level: valuations will be higher the lower the risk levels in the study are.     

Brake Valve Timing and Fuel Injection: a Unified Engine Torque Actuator for Heavy-Duty Vehicles

A unified engine torque actuator for heavy-duty vehicles is developed in this paper. Based on averaging and identification of the instantaneous torque response for changes in brake valve timing and fuel flow, we derive a control oriented engine model of a six cylinder, 350 Hp turbocharged diesel engine, equipped with a compression brake. This work bridges the gap between the detailed compression crank angle based models developed in the engine design community, and the first order lag representation of diesel engine torque response used in the vehicle dynamics community. Moreover, we integrate the compression brake actuator with the service brakes and design a PI-controller that emulates the driver's actions during long descends on grades. The controller simply uses the engine speed measurement to activate the service brakes only when needed.     

Activity settings and travel behaviour: A social contact perspective

Using time-use data from Canada, Norway, and Sweden, this study briefly outlines the essence of the activity setting approach and illustrates one aspect of its usefulness by exploring the impact of social contact on travel behaviour. The activity system approach views behaviour in context. Activity settings are generic components of the activity system and studying them using time-use diaries can provide major insights into travel behaviour. Focusing on social contact, this paper characterizes the social environment in terms of social circle (interaction partners) and social space (location). The analysis shows that there are clear differences in the levels of social interaction across various groups, including those who work at home. The 1992 Canadian data showed people working at the workplace spend relatively more time with others, about 50% of total time awake. Working at home reduced the time with others to a low of 15.7%. when people worked at home the family benefited, almost doubling the time spent with them compared to those working at the workplace. Persons working at home only spend the most time alone. There is a tendency for persons with low social interaction to travel more. It is argued that individual need, or want, social contact and if they cannot find it at the workplace they will seek it elsewhere thus generating travel. Whether this is the result of need or opportunity is of minor relevance, what it does suggest is that working in isolation at home will not necessarily diminish travel but rather may simply change its purpose. This revised version was published online in June 2006 with corrections to the Cover Date.