An integrated methodology for the design of Ro-Ro passenger ships

The present paper provides a brief introduction to the holistic approach to ship design, defines the generic ship design optimization problem and demonstrates its solution by use of advanced optimization techniques

Positive and negative regulation of T cell activation via CD80

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN025334 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

A novel method for safety analysis of Cyber-Physical Systems - Application to a ship exhaust gas scrubber system

Cyber-Physical Systems (CPSs) represent a systems category developed and promoted in the maritime industry to automate functions and system operations. In this study, a novel Combinatorial Approach for Safety Analysis is presented, which addresses the traditional safety methods’ limitations by integrating System Theoretic Process Analysis (STPA), Events Sequence Identification (ETI) and Fault Tree Analysis (FTA). The developed method results into the development of a detailed Fault Tree that captures the effects of both the physical components/subsystems and the software functions’ failures. The quantitative step of the method employs the components’ failure rates to calculate the top event failure rate along with criticality analysis metrics for identifying the most critical components/functions. This method is implemented for an exhaust gas open loop scrubber system safety analysis to estimate its failure rate and identify critical failures considering the baseline system configuration as well as various alternatives with advanced functions for monitoring and diagnostics. The results demonstrate that configurations with SOx sensor continuous monitoring or scrubber unit failure diagnosis/prognosis lead to significantly lower failure rate. Based on the analysis results, the advantages/disadvantages of the novel method are also discussed. This study also provides insights for better safety analysis of the CPSs

Serotonergic modulation of suicidal behaviour : integrating preclinical data with clinical practice and psychotherapy

Many studies have provided important information regarding the anatomy, development and functional organization of the 5-HT system and the alterations in this system that are present within the brain of the suicidal patient. There is also a growing interest in genetic factors associated with suicide, since these may lead to the emergence of personality traits that prove to be long-term predictors of suicidal behaviour. This review will focus on presenting the scientific literature on the role of the serotonergic system in suicidal behaviour as well as dysfunctional attitudes and personality traits associated with the suicidal patient. The association of the serotonin transporter gene, the 5-HT2 receptors and its metabolite 5-hydroxyindoleacetic acid with suicidal behaviour and animal models that may capture the complexity of suicidal behaviour will be discussed. Finally, the relationship between neurobiological models and psychotherapeutic interventions for suicide prevention will be considered with a focus on Schema Therapy (an approach that has shown particular promise in the treatment of suicidal individuals with personality disorders), aiming to invite the reader to integrate some aspects of the neurobiology of human suicidal behaviour into a model of suicide that can be used in a clinical encounter.peer-reviewe

A combinatorial safety analysis of cruise ship Diesel-Electric Propulsion plant blackout

Diesel-Electric Propulsion (DEP) has been widely used for propulsion of various ship types including cruise ships. Considering the potential consequences of blackouts, especially on cruise ships, it is essential to design and operate the ships power plants for avoiding and preventing such events. This study aims at implementing a comprehensive safety analysis for a cruise ship Diesel-Electric Propulsion (DEP) plant focusing on blackout events. The Combinatorial Approach to Safety Analysis (CASA) method is used to develop Fault Trees considering the black out as the top event, and subsequently estimate the blackout frequency as well as implement importance analysis. The derived results demonstrate that the overall blackout frequency is close to corresponding values reported in the pertinent literature as well as estimations based on available accident investigations. This study deduces that the blackout frequency depends on the number of operating Diesel Generators (DG) sets, the DG sets loading profile, the amount of electrical load that can be tripped during overload conditions and the plant operation phase. In addition, failures of the engine auxiliary systems and the fast-electrical load reduction functions as well as the power generation control components are identified as important. This study demonstrates the applicability of the CASA method to complex marine systems and reveals the parameters influencing the investigated system blackout frequency, thus providing better insights for these systems safety analysis and enhancement

Marine dual fuel engine modelling and parametric investigation of engine settings effect on performance-emissions trade-offs

The continuous stringent requirements of the environmental regulations along with the LNG fuel penetration and the development of port and bunkering facilities, render the use of the dual fuel engines an attractive alternative of the traditional ship propulsion plants based on Diesel engines running with HFO for reducing both the plant operating cost and environmental footprint. The present study deals with the computational investigation of a large marine dual fuel (DF) engine of the four-stroke type for comparing its performance and emissions, in both diesel and gas mode operation by using the commercial software GT-ISE. The engine diesel model was initially set up and calibrated to adequately represent the engine operation. Subsequently, the engine dual fuel model was further developed by considering the injection of two different fuels; methane in the cylinder inlet ports and pilot diesel fuel into the engine cylinders. The derived results were analysed for revealing the differences of the engine performance and emissions at each operating mode. In addition, the turbocharger matching was investigated and discussed to enlighten the turbocharging system challenges due to the completely different air−fuel ratio requirements in diesel and gas modes, respectively. Finally, parametric simulations were performed for gas mode operation at different loads by varying pilot fuel injection timing, inlet valve closing and inlet manifold boost pressure, aiming to identify the engine settings that simultaneously reduce CO2 and NOx emissions considering the air−fuel ratio operation window limitations. The parametric study results are discussed to infer the engine optimal settings

Genetic Dissection of the Cellular Pathways and Signaling Mechanisms in Modeled Tumor Necrosis Factor–induced Crohn's-like Inflammatory Bowel Disease

Recent clinical evidence demonstrated the importance of tumor necrosis factor (TNF) in the development of Crohn's disease. A mouse model for this pathology has previously been established by engineering defects in the translational control of TNF mRNA (TnfΔAREmouse). Here, we show that development of intestinal pathology in this model depends on Th1-like cytokines such as interleukin 12 and interferon γ and requires the function of CD8+ T lymphocytes. Tissue-specific activation of the mutant TNF allele by Cre/loxP-mediated recombination indicated that either myeloid- or T cell–derived TNF can exhibit full pathogenic capacity. Moreover, reciprocal bone marrow transplantation experiments using TNF receptor–deficient mice revealed that TNF signals are equally pathogenic when directed independently to either bone marrow–derived or tissue stroma cell targets. Interestingly, TNF-mediated intestinal pathology was exacerbated in the absence of MAPKAP kinase 2, yet strongly attenuated in a Cot/Tpl2 or JNK2 kinase–deficient genetic background. Our data establish the existence of redundant cellular pathways operating downstream of TNF in inflammatory bowel disease, and demonstrate the therapeutic potential of selective kinase blockade in TNF-mediated intestinal pathology

Medstraum : design and operation of the first zero-emission fast catamaran

The paper deals with the design, construction and the early operation of the worldwide 1 st battery driven high-speed catamaran passenger ferry MS Medstraum. The paper elaborates on unique issues of the design process, on the superior hydrodynamic performance, on the modular construction of vessel and on the land-based electrical/charging installation. MS Medstraum was built by Fjellstrand AS and was launched in early June 2022. After successful sea trials that superseded the expectations of designers, builders and operators, achieving a maximum speed of over 27 knots, it started operations in the Stavanger/Norway area in late September 2022. The prototype character of MS Medstraum led to its selection as “Ship of the Year 2022” at the major international maritime exhibition SMM 2022 (September 2022, Hamburg). The presented research is in the frame of the H2020 funded project “TrAM – Transport: Advanced and Modular” (www.tramproject.eu)

Multi-objective Optimization of Cruise ships considering the SOLAS 2009 and GOALDS damage stability

A new formulation for the assessment of ship's survivability in damaged condition, based on the probabilistic concept, was developed in the framework of the EU-funded research project named GOALDS. The investigation of the impact of the new formulation on the design and operational characteristics of cruise ships is the main objective of the present paper. An additional objective is to investigate the possibility of raising the required subdivision index compared to current SOLAS 2009 levels; this is supported by demonstrating the feasibility of representative sample ship designs of enhanced survivability through formalized, multi-objective optimization studies, while considering a risk and cost effectiveness analysis

Best practices in NMs Risk Assessment. Demonstration actions under REACH-NANO and LIFE NANO-RISK Projects

<p>Best practices in NMs Risk Assessment. Demonstration actions under REACH-NANO and LIFE NANO-RISK Projects</p