General rights Copyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Abstract 10A novel methodology has been developed to quantify important saltwater intrusion parameters in a 11 sandbox experiment using image analysis. Existing methods found in the literature are based mainly 12 on visual observations, which are subjective, labour intensive and limit the temporal and spatial 13 resolutions that can be analysed. A robust error analysis was undertaken to determine the optimum 14 methodology to convert image light intensity to concentration. Results showed that defining a 15 relationship on a pixel-wise basis provided the most accurate image to concentration conversion and 16 allowed quantification of the width of the mixing zone between saltwater and freshwater. A high 17 image sample rate was used to investigate the transient dynamics of saltwater intrusion, which 18 rendered analysis by visual observation unsuitable. This paper presents the methodologies developed 19 to minimise human input and promote autonomy, provide high resolution image to concentration 20 conversion, and allow the quantification of intrusion parameters under transient conditions. 21

This paper presents the applications of a novel methodology to quantify saltwater intrusion parameters in laboratory-scale experiments. The methodology uses an automated image analysis procedure, minimizing manual inputs and the subsequent systematic errors that can be introduced. This allowed the quantification of the width of the mixing zone which is difficult to measure in experimental methods that are based on visual observations. Glass beads of different grain sizes were tested for both steady-state and transient conditions. The transient results showed good correlation between experimental and numerical intrusion rates. The experimental intrusion rates revealed that the saltwater wedge reached a steady state condition sooner while receding than advancing. The hydrodynamics of the experimental mixing zone exhibited similar traits; a greater increase in the width of the mixing zone was observed in the receding saltwater wedge, which indicates faster fluid velocities and higher dispersion. The angle of intrusion analysis revealed the formation of a volume of diluted saltwater at the toe position when the saltwater wedge is prompted to recede. In addition, results of different physical repeats of the experiment produced an average coefficient of variation less than 0.18 of the measured toe length and width of the mixing zone. KeywordsSaline water intrusion; Intrusion angle; Width of the mixing zone; Light to concentration conversion.

Network science approaches can enhance global and national coordinated efforts to prevent and manage non-communicable diseases, say Ruth Hunter and colleagues

PurposeThis paper aims to demonstrate the transformative potential of school networks in divided societies, where separate schools often mirror wider ethnic divisions. It describes Shared Education in Northern Ireland, where networks are being utilised to change how Catholic and Protestant schools engage with one another. The concept of boundary crossing is used to frame how staff members build relationships and bridge distinct knowledge communities shaped by socio-cultural practices and identities.Design/Methodology/ApproachA mixed-methods design was employed. Evidence is presented based on a social network analysis of teacher interactions within a Shared Education partnership of five primary schools in Northern Ireland.FindingsThe findings suggest that school networking can overcome systemic separation in divided societies and provide the infrastructure necessary to establish an alternative model for collegial engagement. The structural characteristics of the observed school network are discussed, including comments on its sustainability, the role of boundary-crossing relationships, the professional value for those involved and its transformative potential for society.Originality/valueThis paper provides a unique perspective on the application and utility of school networks for supporting the development of professional communities in challenging circumstances. It also presents valuable social network data on the structure and management of school networks.

Image analysis is a useful tool for visualising flow through laboratory-scale aquifers but existing methods of converting image light intensity to concentration can be labour intensive and time consuming. The new approach proposed in this study utilises the Random Forest machine learning technique to build a calibration model to replace the requirement for unique calibrations of each test aquifer. Calibration images from a previous experimental study were used to train the Random Forest model and the output was compared to the results from a high resolution pixel-wise methodology. The Random Forest model provided a trade-off in accuracy with increased efficiency and reduced sensitivity to image desynchronisation when compared to the pixel-wise method. The reduced accuracy was attributed in part to non-linear lighting distribution across the sandbox, which could be corrected by orientating the backlights effectively. Time savings of around 35% were achieved for this experimental study and this is expected to increase for larger scale studies. The new calibration approach exhibits some promising features in terms of its robustness to experimental error and its ability to process efficiently large-scale experiments in a shorter time frame.