Analysing trade-offs in container loading: Combining load plan construction heuristics with agent-based simulation

This is the accepted version of the following article: Analysing Trade-offs in Container Loading: Combining Load Plan Construction Heuristics with Agent-based Simulation. International Transactions in Operational Research, 20(4): 471-491which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/itor.12017/abstractIn this paper we describe two operations research techniques, cutting and packing optimisation (CPO) and simulation, and present a multi-methodology approach for analysing the trade-offs between loading efficiency and various important practical considerations in relation to the cargo, such as its stability, fragility or possible cross-contamination between different types of items over time. The feasibility of this approach is demonstrated by considering a situation where the items to be loaded have differing degrees of perishability and where badly deteriorated items can affect those in their immediate vicinity (e.g. through the spread of mould). Our approach uses the output of the CPO algorithms to create agents that simulate the spread of mould through proximity-based interactions between the agents. The results show the trade-offs involved in container utilisation and the propagation of mould, without evidence of any correlation between them. The contribution of this research is the methodology and the feasibility study

Analyzing Seasonality in Welsh Room Occupancy Data

This paper analyzes the seasonal variations in occupancy rates for the accommodation sector in Wales over the period 1998 to 2000. The approach is based on a combination of principal components and cluster analysis. The results are used to group establishments with similar performance profiles. Some general relationships between occupancy performance and the characteristics of the accommodation businesses in Wales are identified. The analysis extends to the hotel and other parts of the serviced accommodation sector allowing comparisons to be drawn. Several concrete pointers for tailoring marketing strategies to the requirements of different accommodation segments are discussed

VFR tourism: the importance of university students as hosts

The role of university students in attracting friends and relatives as visitors to their place of study is examined. A questionnaire survey conducted at a UK university is presented in the context of general UK tourism and the visits to friends and relatives (VFR) sector in particular. It is demonstrated that universities represent large, frequently underestimated, generators of VFR tourism and that significant differences exist between the friends and the relatives' components. The paper draws concrete conclusions about the marketing opportunities and argues that the students themselves represent the most effective target for promotion efforts. It also points out possibilities for turning day visits into overnight stays, particularly in the relatives' segment

Seasonality of tourism in Wales: a comparative analysis

This paper examines the seasonal pattern for different types of domestic tourism demand in the UK during 1994–2000. The focus is on Wales, a region with a particularly pronounced tourism seasonality. The characteristics of the Welsh seasonal pattern are identified and compared with other UK regions, notably Scotland. An overview of various different methods for quantifying these seasonal variations is presented. Various scalar measures are used to evaluate the inequality of the distribution of tourism trips within a year. The stability of seasonal patterns between the years is also examined and more complex methodologies, such as Seasonal Decomposition, are applied in order to assess in detail the differences in the seasonal behaviour of demand among the UK home nations. On the basis of the analysis, policy implications for tackling the seasonality problem are discussed

Developing effective strategies for tackling seasonality in the tourism industry

Seasonality is a key aspect for the performance of the majority of tourism enterprises and a central theme for policy makers. The usual practice of strategy formulation in this area, whilst often involving a sound analysis of objective performance data, largely ignores the perceptions which the businesses concerned have of the seasonality issue. This paper demonstrates that the heterogeneity of attitudes and perceptions in the sector need to be recognised when developing effective strategies for tackling seasonality. An empirical quantitative approach is applied using occupancy data of the serviced accommodation sector in addition to a survey of owner/managers. The findings indicate that an insufficiently detailed level of segmentation of the business sector concerned may lead to ill-focused broad-brush strategies and consequent misallocations of resources. The paper contends that policy makers in this area need information beyond what can be obtained from the usual performance measurement systems

Proximity-based modelling of cross-contamination through agent-based simulation: a feasibility study

types: Article“This is a post-peer-review, pre-copyedit version of an article published in Health Systems. The definitive publisher-authenticated version: Proximity-based modelling of cross-contamination through agent-based simulation: a feasibility study". Health Systems, 2(1): 61-71 is available online at: http://www.palgrave-journals.com/hs/journal/v2/n1/full/hs201216a.html”Proximity-based modelling methodology enables mathematical representation of a real system that is characterised by the existence of entities that come into physical contact. Healthcare systems can benefit from this methodology since physical proximity between entities (e.g., patients, clinical items like surgical equipment and blood units) can result in the spread of infectious diseases and cross-contamination. The existing analytical techniques, which are mainly based on differential equations, are unsuitable for representing the fine-grained, micro-world view of the entity interactions that we intend to model. We therefore extend Agent-Based Simulation (ABS) by enabling individual agents to be aware of the physical location of the other agents being modelled in a 3-dimensional space – this is a perquisite for our proximity-based modelling methodology. To demonstrate the feasibility of our approach, we experiment with a scenario wherein boxes of degradable clinical items, modelled as agents, are stored in close proximity. We use Cutting and Packing Optimisation (CPO) algorithms from literature to define the arrangement of these agents in the 3-D space and to make the individual agents ‘location-aware’. An ABS model then simulates cross-contamination by modelling the spread of contaminants among the agents confined in the well-defined space. Our approach can be used to model analogous situations wherein physical proximity between entities in the underlying system is a necessary condition for entity interactions