Water-Column Variability Assessment for Underway Profilers to Improve Efficiency and Accuracy of Multibeam Surveys

With the advent of underway profilers, sampling the water-column to obtain sound speed corrections is no longer a detriment to hydrographic survey efficiency. Instead, the challenge has become deciding how many casts are necessary to maintain a desired level of multibeam sounding accuracy, while not needlessly overworking the profiler. Ray tracing uncertainty analysis can determine in hindsight whether a particular sampling interval is adequate or not. Based on this methodology, an algorithm was developed to generate recommended sampling intervals based on successively acquired sound speed profiles, allowing the MVP to run in a “cruise-control” mode where the sampling interval is altered in response to changing oceanographic conditions. In collaboration with Rolls Royce, the algorithm was implemented in Python and loosely couples with the MVP controller software such that the recommended sampling interval can be adjusted without operator intervention. Integration of the software with the MVP controller was successfully tested aboard the NOAA Ship Ferdinand R. Hassler in September of 2012. Initial results from field trials and from analysis of existing data sets are presented

Streamlining Sound Speed Profile Pre-Processing: Case Studies and Field Trials

High rate sound speed profiling systems have the potential to maximize the efficiency of multibeam echosounder systems (MBES) by increasing the accuracy at the outer edges of the swath where refraction effects are at their worst. In some cases, high rate sampling on the order of tens of casts per hour is required to capture the spatio-temporal oceanographic variability and this increased sampling rate can challenge the data acquisition workflow if refraction corrections are to be applied in real-time. Common bottlenecks result from sound speed profile (SSP) preprocessing requirements, e.g. file format conversion, cast extension, reduction of the number of points in the cast, filtering, etc. Without the ability to quickly pre-process SSP data, the MBES operator can quickly become overwhelmed with SSP related tasks, potentially to the detriment of their other duties. A series of algorithms are proposed in which SSPs are automatically pre-processed to meet input criteria of MBES acquisition systems, specifically the problems of cast extrapolation and thinning are addressed. The algorithmic performance will be assessed in terms of sounding uncertainty through a series of case studies in a variety of oceanographic conditions and water depths. Results from a field trial in the French Mediterranean will be used to assess the improvement in real-time MBES acquisition workflow and survey accuracy and will also highlight where further improvements can be made in the pre-processing pipeline

Design for Island Life Travelling Exhibition

A week-long pop-up exhibit of Design Innovation student work carried out in the Outer Hebrides from The Glasgow School Art. Students from our Masters in Design Innovation courses visited island communities earlier in the year as part of their research. Now we want to share our designs with you and hear your feedback. Each pop-up will last for a couple of hours for informal viewing of the exhibition and a short formal presentation of the work

Efficient Planning of Multi-Robot Collective Transport using Graph Reinforcement Learning with Higher Order Topological Abstraction

Efficient multi-robot task allocation (MRTA) is fundamental to various time-sensitive applications such as disaster response, warehouse operations, and construction. This paper tackles a particular class of these problems that we call MRTA-collective transport or MRTA-CT -- here tasks present varying workloads and deadlines, and robots are subject to flight range, communication range, and payload constraints. For large instances of these problems involving 100s-1000's of tasks and 10s-100s of robots, traditional non-learning solvers are often time-inefficient, and emerging learning-based policies do not scale well to larger-sized problems without costly retraining. To address this gap, we use a recently proposed encoder-decoder graph neural network involving Capsule networks and multi-head attention mechanism, and innovatively add topological descriptors (TD) as new features to improve transferability to unseen problems of similar and larger size. Persistent homology is used to derive the TD, and proximal policy optimization is used to train our TD-augmented graph neural network. The resulting policy model compares favorably to state-of-the-art non-learning baselines while being much faster. The benefit of using TD is readily evident when scaling to test problems of size larger than those used in training.Comment: This paper has been accepted to be presented at the IEEE International Conference on Robotics and Automation, 202

Illumina WG-6 BeadChip strips should be normalized separately

<p>Abstract</p> <p>Background</p> <p>Illumina Sentrix-6 Whole-Genome Expression BeadChips are relatively new microarray platforms which have been used in many microarray studies in the past few years. These Chips have a unique design in which each Chip contains six microarrays and each microarray consists of two separate physical strips, posing special challenges for precise between-array normalization of expression values.</p> <p>Results</p> <p>None of the normalization strategies proposed so far for this microarray platform allow for the possibility of systematic variation between the two strips comprising each array. That this variation can be substantial is illustrated by a data example. We demonstrate that normalizing at the strip-level rather than at the array-level can effectively remove this between-strip variation, improve the precision of gene expression measurements and discover more differentially expressed genes. The gain is substantial, yielding a 20% increase in statistical information and doubling the number of genes detected at a 5% false discovery rate. Functional analysis reveals that the extra genes found tend to have interesting biological meanings, dramatically strengthening the biological conclusions from the experiment. Strip-level normalization still outperforms array-level normalization when non-expressed probes are filtered out.</p> <p>Conclusion</p> <p>Plots are proposed which demonstrate how the need for strip-level normalization relates to inconsistent intensity range variation between the strips. Strip-level normalization is recommended for the preprocessing of Illumina Sentrix-6 BeadChips whenever the intensity range is seen to be inconsistent between the strips. R code is provided to implement the recommended plots and normalization algorithms.</p

Integrated plant conservation on Pitcairn Island, South Central Pacific

Pitcairn Island is a small, isolated island at the eastern extremity of the main group of Polynesian islands, roughly half way between New Zealand and South America and just south of the Tropic of Capricorn. The research interest of Trinity College, Dublin (TCD) in the island began in 1991 during the Sir Peter Scott Commemorative Expedition to the Pitcairn Islands, which focussed its attention mainly on ‘nearby’ Henderson Island (a World Heritage Site) and two atolls Oeno and Ducie. During this expedition it became apparent that the main conservation issues with the flora of these islands was on Pitcairn itself. As a U.K. Overseas Territory governed from the British High Commission in New Zealand, the responsibility for biodiversity conservation on the island rests with the UK Government. Accordingly, TCD and the Irish National Parks and Wildlife Service (NPWS) secured funding from the U.K. Foreign & Commonwealth Office in 1997 to examine in detail the floristics, vegetation communities and conservation status of the native flora

Monitoring methods for Killarney Fern (Trichomanes speciosum Willd.) in Ireland

Trichomanes speciosum Willd is categorised as rare and vulnerable in Ireland and is listed under Annex II and IV of the EU Habitats Directive (Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora). T. speciosum, commonly known as the Killarney Fern or Bristle Fern, belongs to the Filmy Fern family (Hymenophyllaceae) and is the only European representative of the genus Trichomanes. T. speciosum is most abundant in the Azores, outside of which it is most frequently found in Ireland and Britain.Parks & Wildlife Service (NPWS), Department of Arts, Heritage and the Gaeltach

Knowledge Transfer for Occupational Health and Safety: Cultivating Health and Safety Learning Culture in Construction Firms

Within the last decades the incidence of workspace injuries and fatalities in the UK construction industry has declined markedly following the developments in occupational health and safety (OHS) management systems. However, safety statistics have reached a plateau and actions for further improvement of OHS management systems are called for. OHS is a form of organizational expertise that has both tacit and explicit dimensions and is situated in the ongoing practices. There is a need for institutionalization and for the transfer of knowledge across and along construction supply chains to reduce OHS risks and facilitate cultural change. The focus of this article is the factors that facilitate OHS knowledge transfer in and between organizations involved in construction projects. An interpretative methodology is used in this research to embrace tacit aspects of knowledge transfer and application. Thematic analysis is supported by a cognitive mapping technique that allows understanding of interrelationships among the concepts expressed by the respondents. This paper demonstrates inconsistency in OHS practices in construction organizations and highlights the importance of cultivating a positive safety culture to encourage transfer of lessons learnt from good practices, incidents, near misses and failures between projects, from projects to programmes and across supply chains. Governmental health and safety regulations, norms and guidelines do not include all possible safety issues specific to different working environments and tied to work contexts. The OHS system should encourage employees to report near misses, incidents and failures in a ‘no-blame’ context and to take appropriate actions. This research provides foundation for construction project practitioners to adopt more socially oriented approaches towards promoting learning-rich organizational contexts to overcome variation in the OHS and move beyond the current plateau reached in safety statistics