Prediction of biological development effects on drag forces of ceramic hull coating using Reynolds-averaged Navier-Stokes-based solver.

Ships in service feature surfaces that exhibit biofouling, which alters the hydrodynamics of the vessels, thus affecting their normal displacement and significantly increasing their fuel consumption. The application of three types of ceramic coatings as ecological, effective and durable alternatives to commercial silicone-based marine coatings is investigated in this study. Three different ceramic glazes and two control commercial paints are analysed in an actual environment during 20 months of exposure to simulate the navigation conditions such that growth and roughness data can be obtained and then applied to computational fluid dynamics (CFD) software using an open-source Reynolds-averaged Navier-Stokes solver. The CFD results are validated under smooth hull conditions with a full-scale Kriso Container Ship (KCS) model and with different levels of hull roughness. The developed approach shows that the drag in hulls coated with conventional paint is 19% greater than that in hulls with ceramic coating.

Quantitative Analysis on Risk Influencing Factors in the Jiangsu Segment of the Yangtze River.

Quantitative risk influencing factors (RIFs) are proposed, using the Conjugate Bayesian update approach to analyze 945 collision accidents and incidents cases from the Jiangsu Segment of the Yangtze River over five years from 2012 to 2016. The accident probability is compared under a pairwise comparison mode in order to reflect the relative risk between accidental situations. The Bayesian update mode is constructed to quantitatively evaluate the relative importance of different RIFs. The riskiest segment of Jiangsu Waterways as well the main causations of collisions are identified based on the distributions of collision risk in the six segments of the waterways. The results can support managers to develop the most effective policies to mitigate the collision risk.

Analysis of the influence of human errors on the occurrence of coastal ship accidents in different wave conditions using Bayesian Belief Networks.

The paper describes a study aiming to assess the human error contribution in ship accidents in different weather conditions and the contribution that high significant wave heights have in the occurrence of certain accident typologies. To this aim, a Bayesian Belief Network model is developed, which includes variables related to the maritime accident but also to the different wave conditions. For the quantification of the conditional probability tables the maritime accident database of the Portuguese Maritime Authority is used, which includes 857 validated accidents registered in the period 1997-2006. Similarly, several significant wave height databases are used to populate the node correspondent to this variable. The importance of accurate estimation of the significant wave height is also discussed. To substantiate this discussion a comparison between hard evidence (ε) and a soft one (µ,σ) is performed for the significant wave height node of the BBN model. The application of different combinations of evidence in the model allows the identification of patterns of influence of the human error cause in comparison with others, namely with the sea and weather one. The results show one apparent high-risk acceptance within the crews of the fishing vessels and low risk perception in the recreational vessels. Based on the results, are provided recommendations to decrease the risk associated to specific probable causes.

An Evidential Reasoning-Based CREAM to Human Reliability Analysis in Maritime Accident Process.

This article proposes a modified cognitive reliability and error analysis method (CREAM) for estimating the human error probability in the maritime accident process on the basis of an evidential reasoning approach. This modified CREAM is developed to precisely quantify the linguistic variables of the common performance conditions and to overcome the problem of ignoring the uncertainty caused by incomplete information in the existing CREAM models. Moreover, this article views maritime accident development from the sequential perspective, where a scenario- and barrier-based framework is proposed to describe the maritime accident process. This evidential reasoning-based CREAM approach together with the proposed accident development framework are applied to human reliability analysis of a ship capsizing accident. It will facilitate subjective human reliability analysis in different engineering systems where uncertainty exists in practice.

An overview of occupational accidents notification systems within the enlarged EU.

This paper describes a comparative analysis of the official forms used for reporting occupational accidents within the EU-27 member states. The comparison is based on two analysis grids (coding schedule) created to that effect, which incorporate a set of evaluation criteria and an interpretation key. The results obtained in the analysis allowed for attention to be drawn to the relevant attributes of such forms in terms of their content and format/structure. It also revealed the main similarities and differences between each country, providing a complete assessment of the 27 member states. The discussion gives account of the level of implementation of the "new" Eurostat variables within the European Statistics of Accidents at Work (ESAW). Furthermore, the study shows that certain formats (structure of information fields) appear to facilitate completeness of the information collected. It has also demonstrated that the European harmonisation process is still far from completion, although the newcomer states seem to be adjusting quickly to the process. The findings of this study may bring useful insights to national authorities and European policy-makers, or to employers/enterprises wishing to implement their internal procedures aligned with the ESAW methodology. The scientific community is another interest group, whose research relies on official statistics, preferably comparable across all countries.

The added value of the new ESAW/Eurostat variables in accident analysis in the mining and quarrying industry.

INTRODUCTION: This paper presents a study on the causes and circumstances of occupational accidents in the Portuguese Mining and Quarrying (M&Q) activity sector. METHOD: To this effect, it uses national accident data (2001-2003), giving particular attention to the newly implemented harmonized ESAW/Eurostat variables. The study begins with a broad description of the M&Q sector and identifies its "typical accident." A series of accident pyramids are used to discriminate between causal patterns of fatal and non-fatal accidents. The causation mechanisms of the "typical accidents" (fatal and non-fatal) are established by examining the statistical dependency between pairs of modalities of two key variables: the Contact and the Deviation. RESULTS: The results obtained by this method revealed certain details of the cause-effect mechanism that were unknown before, which also facilitate prioritizing preventive strategies. The study highlights the benefits of the new Eurostat variables for the production of accident statistics. IMPACT ON INDUSTRY: The consistent adoption of harmonized classifications has a potentially positive impact on several communities: researchers will find it easier to compare their studies; the national authorities can plan more target-oriented preventive strategies; and the individual organizations may use this instrument to facilitate benchmarking of their performance indicators.