Optimization of container process at seaport terminals

Seaport container terminals are an important part of the logistics systems in international trades. This paper investigates the relationship between quay cranes, yard machines and container storage locations in a multi-berth and multi-ship environment. The aims are to develop a model for improving the operation efficiency of the seaports and to develop an analytical tool for yard operation planning. Due to the fact that the container transfer times are sequence-dependent and with the large number of variables involve, the proposed model cannot be solved in a reasonable time interval for realistically sized problems. For this reason, List Scheduling and Tabu Search algorithms have been developed to solve this formidable and NP-hard scheduling problem. Numerical implementations have been analysed and promising results have been achieved.

Genetic algorithms to schedule container transfers at multimodal terminals

Optimising the container transfer schedule at the multimodal terminals is known to be NP-hard, which implies that the best solution becomes computationally infeasible as problem sizes increase. Genetic Algorithm (GA) techniques are used to reduce container handling/transfer times and ships' time at the port by speeding up handling operations. The GA is chosen due to the relatively good results that have been reported even with the simplest GA implementations to obtain near-optimal solutions in reasonable time. Also discussed, is the application of the model to assess the consequences of increased scheduled throughput time as well as different strategies such as the alternative plant layouts, storage policies and number of yard machines. A real data set used for the solution and subsequent sensitivity analysis is applied to the alternative plant layouts, storage policies and number of yard machines.

Analysis of terrain geometry representations for traversability of a Mars rover

For a planetary rover to successfully traverse across unstructured terrain autonomously, one of the major challenges is to assess its local traversability such that it can plan a trajectory to achieve its mission goals efficiently while minimising risk to the vehicle itself. This paper aims to provide a comparative study on different approaches for representing the geometry of Martian terrain for the purpose of evaluating terrain traversability. An accurate representation of the geometric properties of the terrain is essential as it can directly affect the determination of traversability for a ground vehicle. We explore current state-of-the-art techniques for terrain estimation, in particular Gaussian Processes (GP) in various forms, and discuss the suitability of each technique in the context of an unstructured Martian terrain. Furthermore, we present the limitations of regression techniques in terms of spatial correlation and continuity assumptions, and the impact on traversability analysis of a planetary rover across unstructured terrain. The analysis was performed on datasets of the Mars Yard at the Powerhouse Museum in Sydney, obtained using the onboard RGB-D camera.

On standby? A comparison of online and offline witnesses to bullying and their bystander behaviour

Given their ubiquitous presence as witnesses to school-yard bullying, the role of the ‘bystander’ has been studied extensively. The prevalence and behaviour of bystanders to cyberbullying, however, is less understood. In an anonymous, school-based questionnaire, 716 secondary school students from South-East Queensland reported whether they had witnessed traditional and/or cyberbullying, and how they responded to each type. Overlap in bystander roles between online and offline environments was examined, as was their relationship to age and gender. Students who witnessed traditional bullying were more likely to have witnessed cyberbullying. Bystanders’ behaviour was sometimes similar in both contexts of traditional and cyberbullying, mainly if they were outsiders but half of the 256 students who reported witnessing both traditional and cyberbullying, acted in different roles across the two environments. The implications of the findings are discussed in the context of previous research on cyberbullying and traditional-bystanders. Future research should further explore the role of bystanders online, including examining whether known predictors of traditional-bystander behaviour similarly predict cyber-bystander behaviour.

How long does stigma impact property values

Purpose - The purpose of this paper is to determine the impact stigma has on property values and how long the stigma remains after the Not in My Back Yard (NIMBY) structure has been removed. Design/methodology/approach - A quantitative analysis was undertaken, using a high voltage overhead transmission line (HVOTL) case study, to determine the effect on property values prior and post removal of the NIMBY structure. A repeat sales index in conjunction with the regression analysis determined the length of time, the stigma remained after removal of the NIMBY structure. Findings - The results show that while the NIMBY is in place the impact on value is confined to those properties in close proximity. This is in contradiction to the findings, where on removal of the NIMBY the property values of the whole neighbourhood improve with the stigma remaining for 3 to 4 years. Research Implications - The implication of this research is that property Valuers need to change the way they take into account the presence of NIMBYs when valuing property with more emphasis, being placed on the neighbourhood rather than just the properties in close proximity. While the HVOTL was in place, only properties in close proximity were negatively affected, but on removal of the HVOTL the whole neighbourhood increased in value. Originality/value - Results expand on current knowledge by demonstrating the length of time the market takes to adjust to the removal of a NIMBY structure.