The many-to-many location-routing problem

In this paper the many to many location routing problem is introduced, and its relationship to various problems in distribution management is emphasised. Useful mathematical formulations which can be easily extended to cater for other related problems are produced. Techniques for tackling this complex distribution problem are also outlined.

The development of an advanced ship evacuation simulation software product and associated large scale testing facility for the collection of human shipboard behaviour data

When designing a new passenger ship or modifying an existing design, how do we ensure that the proposed design and crew emergency procedures are safe from an evacuation point of view? In the wake of major maritime disasters such as the Herald of Free Enterprise and the Estonia and in light of the growth in the numbers of high density, high-speed ferries and large capacity cruise ships, issues concerned with the evacuation of passengers and crew at sea are receiving renewed interest. In the maritime industry, ship evacuation models offer the promise to quickly and efficiently bring evacuation considerations into the design phase, while the ship is "on the drawing board". maritimeEXODUS-winner of the BCS, CITIS and RINA awards - is such a model. Features such as the ability to realistically simulate human response to fire, the capability to model human performance in heeled orientations, a virtual reality environment that produces realistic visualisations of the modelled scenarios and with an integrated abandonment model, make maritimeEXODUS a truly unique tool for assessing the evacuation capabilities of all types of vessels under a variety of conditions. This paper describes the maritimeEXODUS model, the SHEBA facility from which data concerning passenger/crew performance in conditions of heel is derived and an example application demonstrating the models use in performing an evacuation analysis for a large passenger ship partially based on the requirements of MSC circular 1033.

The collection of pre-evacuation times from evacuation trials involving a Hospital Outpatient area and a University Library facility

This paper presents data relating to occupant pre-evacuation times from a university and a hospital outpatient facility. Although the two structures are entirely different they do employ relatively similar procedures: members of staff sweeping areas of the structure to encourage individuals to evacuate. However, the manner in which the dependent population reacts to these procedures is quite different. In the hospital case the patients only evacuated once a member of the nursing staff had instructed them to do so while in the university evacuation the students were less dependent upon the actions of the staff with over 50% of them evacuating with no prior prompting. Although this data may be useful in a variety of areas, it was collected primarily for use within evacuation models.

Effect of bend orientation on life and puncture point location due to solid particle erosion of a high concentration flow in pneumatic conveyors

An investigation into predicting failure of pneumatic conveyor pipe bends due to hard solid particle impact erosion has been carried out on an industrial scale test rig. The bend puncture point locations may vary with many factors. However, bend orientation was suspected of being a main factor due to the biased particle distribution pattern of a high concentration flow. In this paper, puncture point locations have been studied with different pipe bend orientations and geometry (a solids loading ratio of 10 being used for the high concentration flow). Test results confirmed that the puncture point location is indeed most significantly influenced by the bend orientation (especially for a high concentration flow) due to the biased particle distribution and biased particle flux distribution.

Ultra-wideband cognitive interrogator network for indoor location tracking - part 1: system architecture and network performance analysis

We explore the potential application of cognitive interrogator network (CIN) in remote monitoring of mobile subjects in domestic environments, where the ultra-wideband radio frequency identification (UWB-RFID) technique is considered for accurate source localization. We first present the CIN architecture in which the central base station (BS) continuously and intelligently customizes the illumination modes of the distributed transceivers in response to the systempsilas changing knowledge of the channel conditions and subject movements. Subsequently, the analytical results of the locating probability and time-of-arrival (TOA) estimation uncertainty for a large-scale CIN with randomly distributed interrogators are derived based upon the implemented cognitive intelligences. Finally, numerical examples are used to demonstrate the key effects of the proposed cognitions on the system performance

The co-location of offshore windfarms and decapod fisheries in the UK: Constraints and opportunities

The offshore wind sector in the UK is expanding rapidly and is set to occupy significant areas of the coastal zone, making it necessary to explore the potential for co-location with other economic activities. The presence of turbine foundations introduces hard substrates into areas previously dominated by soft sediments, implying that artificial reef effects may occur, with potential benefits for fisheries. This review focuses on the possibilities for locating fisheries for two commercially important decapods, the brown crab Cancer pagurus and the European lobster Homarus gammarus, within offshore wind farms. Existing understanding of habitat use by C pagurus and H. gammarus suggests that turbine foundations have the potential to act as artificial reefs, although the responses of these species to noise and electromagnetic fields are poorly understood. Offshore wind farm monitoring programmes provide very limited information, but do suggest that adult C pagurus associate with turbine foundations, which may also serve as nursery areas. There was insufficient deployment and monitoring of rock armouring to draw conclusions about the association of H. gammarus with offshore wind farm foundations. The limited information currently available demonstrates the need for further research into the ecological and socioeconomic issues surrounding fishery co-location potential.

Seasonal ITCZ migration dynamically controls the location of the (sub)tropical Atlantic biogeochemical divide

Inorganic nitrogen depletion restricts productivity in much of the low-latitude oceans, generating a selective advantage for diazotrophic organisms capable of fixing atmospheric dinitrogen (N2). However, the abundance and activity of diazotrophs can in turn be controlled by the availability of other potentially limiting nutrients, including phosphorus (P) and iron (Fe). Here we present high-resolution data (∼0.3°) for dissolved iron, aluminum, and inorganic phosphorus that confirm the existence of a sharp north–south biogeochemical boundary in the surface nutrient concentrations of the (sub)tropical Atlantic Ocean. Combining satellite-based precipitation data with results from a previous study, we here demonstrate that wet deposition in the region of the intertropical convergence zone acts as the major dissolved iron source to surface waters. Moreover, corresponding observations of N2 fixation and the distribution of diazotrophic Trichodesmium spp. indicate that movement in the region of elevated dissolved iron as a result of the seasonal migration of the intertropical convergence zone drives a shift in the latitudinal distribution of diazotrophy and corresponding dissolved inorganic phosphorus depletion. These conclusions are consistent with the results of an idealized numerical model of the system. The boundary between the distinct biogeochemical systems of the (sub)tropical Atlantic thus appears to be defined by the diazotrophic response to spatial–temporal variability in external Fe inputs. Consequently, in addition to demonstrating a unique seasonal cycle forced by atmospheric nutrient inputs, we suggest that the underlying biogeochemical mechanisms would likely characterize the response of oligotrophic systems to altered environmental forcing over longer timescales.

The co-location of offshore windfarms and decapod fisheries in the UK: Constraints and opportunities

The offshore wind sector in the UK is expanding rapidly and is set to occupy significant areas of the coastal zone, making it necessary to explore the potential for co-location with other economic activities. The presence of turbine foundations introduces hard substrates into areas previously dominated by soft sediments, implying that artificial reef effects may occur, with potential benefits for fisheries. This review focuses on the possibilities for locating fisheries for two commercially important decapods, the brown crab Cancer pagurus and the European lobster Homarus gammarus, within offshore wind farms. Existing understanding of habitat use by C pagurus and H. gammarus suggests that turbine foundations have the potential to act as artificial reefs, although the responses of these species to noise and electromagnetic fields are poorly understood. Offshore wind farm monitoring programmes provide very limited information, but do suggest that adult C pagurus associate with turbine foundations, which may also serve as nursery areas. There was insufficient deployment and monitoring of rock armouring to draw conclusions about the association of H. gammarus with offshore wind farm foundations. The limited information currently available demonstrates the need for further research into the ecological and socioeconomic issues surrounding fishery co-location potential.

An Investigation into the Link between UK Credit Union Characterisitics, Location and their Success

The unique characteristics of credit unions reduces the information asymmetry that is prevalent in credit making decisions, enabling them to provide loans where other financial institutions cannot. This makes them a potential tool in the fight against financial exclusion. Yet, the UK credit union movement is not regarded as being successful, even though there is evidence of much financial exclusion. This study is cross sectional in form, and evaluates characteristics that may contribute to the success of the UK credit union movement at national and regional level, in 2000. The findings are used to consider the impact of recent regulatory changes on the movement. The key findings are that there is a significant relationship between the success of a credit union, its size and the deprivation of the ward from which it sources its members. More specifically, larger credit unions and those located in more affluent wards, are more successful. Affiliation to the Irish League of Credit Unions and having a common bond of occupation, are also found to be contributing factors to credit union success. These results are taken as providing support for the recent changes implemented by the Financial Services Authority (FSA), which is likely to result in the emergence of larger credit unions (through mergers), run by appropriately qualified persons, serving a more mixed-income membership base. It is, however, noted that the history of the UK movement is one of missed opportunities and only time will tell whether credit unions have the wherewithal to accept current opportunities.