2,818 research outputs found

    Paths forward for sustainable maritime transport : A techno-economic optimization framework for next generation vessels

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    Climate change is omnipresent in our society. It is known that climate change is occurring, and that additional warming is unavoidable. Therefore, the decarbonization of industrial sectors has gained increased importance in the last years. The maritime transport sector is one of the most targeted industries as it contributes to approximately 3% of global GHG emissions. Nevertheless, maritime transport accounts for up to 80% of the global trade volume, underlying its importance for the world economy. A technical feasible and reliable solution is, thus, essential for the shipping industry to reach the ambitious climate goals established by the Paris Agreement. In the past, the maritim sector has been highly reliant on fossil fuels, using heavy fuel oil as the major energy input. Heavy fuel oil has been the most dominant fuel in the industry due to its cost advantage and high energy density. Recent developments in the maritime industry promote the emergence of dual fuel engines (e.g. LNG and HFO). Even though increased efficiencies and low carbon fuels can reduce maritime pollution, they cannot achieve carbon neutrality. In the long-term, it will be necessary to implement zero emission fuels including green hydrogen, ammonia, methanol, and LNG. The implementation of new sustainable technologies and fuels in the maritime sector will however depend on their economic competitiveness compared to alternative solutions. Therefore, the following research question arises: When can sustainable maritime transport achieve cost parity compared to conventional technologies? The master thesis investigates the break-even point of sustainable shipping technologies in order to achieve climate targets. Thereby, the focus is set on the life cycle costs of different maritime technologies. A techno-economic framework is necessary to decide on the most suitable options for the industry in prospective years. The framework should be able to analyze current as well as prospective technologies, and guide during the technological decision-making process. Therefore, the definition of key performance indicators (KPI) is essential to set a standard for further assessments. The KPIs will be the main value to compare technologies from an economic perspective. In order to answer the research question a case study is developed. The case study is formed by an extensive literature review on current and next-generation sustainable energy systems for vessels. A priority lies on potential carbon neutral technologies and engines such as fuel cells and battery systems based on a predetermined shipping route and shipping class. In a first step, a simulation model for the developed case is established. The output of the simulation model will then be used in the techno-economic framework, connecting components of the system through thermodynamic and physical properties. In a last step, cost functions translate the systems behavior into economic behavior. Once the case study is analyzed, a statistical model is applied on the results in order to evaluate the system under varying boundary conditions. This sensitivity approach is further necessary to underline the impact of the aforementioned KPIs. By that, the robustness of the framework is tested and secured. Finally, the results of the analysis are explained and interpreted with regard to the research question. A conclusion is drawn regarding the potential economic benefits of sustainable maritime transport technologies within the light of potential market access.The results of the thesis are to be documented in a scientifically appropriate manner and discussed within the context of existing literature and regulatory targets for the industry

    Dilution of seawater affects the Ca2 + transport in the outer mantle epithelium of crassostrea gigas

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    Varying salinities of coastal waters are likely to affect the physiology and ion transport capabilities of calcifying marine organisms such as bivalves. To investigate the physiological effect of decreased environmental salinity in bivalves, adult oysters (Crassostrea gigas) were exposed for 14 days to 50% seawater (14) and the effects on mantle ion transport, electrophysiology and the expression of Ca2+ transporters and channels relative to animals maintained in full strength sea water (28) was evaluated. Exposure of oysters to a salinity of 14 decreased the active mantle transepithelial ion transport and specifically affected Ca2+ transfer. Gene expression of the Na+/K+-ATPase and the sarco(endo)plasmic reticulum Ca2+-ATPase was decreased whereas the expression of the T-type voltage-gated Ca channel and the Na+/Ca2+-exchanger increased compared to animals maintained in full SW. The results indicate that decreased environmental salinities will most likely affect not only osmoregulation but also bivalve biomineralization and shell formation.Funding Agency European Union (EU) 605051 Swedish Mariculture Research Center, SWEMARC, University of Gothenburg Herbert & Karin Jacobssons Stiftelse 15/h17 Helge Ax:son Johnsons Stiftelse F18-0128 Portuguese Foundation for Science and Technology UID/Multi/04326/2019 Portuguese Foundation for Science and Technology UID/Multi/04326/2019 FCT, under the "Norma Transitoria" DL57/2016/CP1361/CT0020 DL57/2016/CP1361/CT0011info:eu-repo/semantics/publishedVersio

    Stakeholder Contributions to Container Port Capacity: A Survey of Port Authorities

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    Given recent concerns about North American port congestion, this paper examines stakeholder involvement in expanding port capacity to meet significant volume growth. North American container port authorities were surveyed to identify key capacity factors and subsequent participation requirements by stakeholders such as terminal operators, longshore labor, railroads, steamship lines, truckers, and government. The resulting analysis indicates port frustration with participation currently offered by all stakeholders, especially the federal government and railroads. Such results further validate the requirement for a multi-stakeholder approach to port capacity expansion and suggest the need for national freight policy and planning leadership

    Stakeholder Contributions to Container Port Capacity: A Survey of Port Authorities

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    Given recent concerns about North American port congestion, this paper examines stakeholder involvement in expanding port capacity to meet significant volume growth. North American container port authorities were surveyed to identify key capacity factors and subsequent participation requirements by stakeholders such as terminal operators, longshore labor, railroads, steamship lines, truckers, and government. The resulting analysis indicates port frustration with participation currently offered by all stakeholders, especially the federal government and railroads. Such results further validate the requirement for a multi-stakeholder approach to port capacity expansion and suggest the need for national freight policy and planning leadership

    PLoS One

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    Mice (Mus musculus) are the most commonly used laboratory animals. Viral metagenomics on tissues of immunodeficient mice revealed sequences of a novel mammalian astrovirus. Using PCR, we screened mice from 4 breeders, 4 pharmaceutical companies, 14 research institutes and 30 universities in the US and Japan. Mice from one US breeder tested positive while none from Japanese breeders were positive for MuAstV. Mice in over half of the universities (19/30), institutes (7/14) and pharmaceutical animal facilities (2/4) investigated revealed the presence of MuAstV. Nine mice strains tested positive including both immunodeficient strains (NSG, NOD-SCID, NSG-3GS, C57BL6-Timp-3 (-/-), and uPA-NOG) and immunocompetent strains (B6J, ICR, Bash2, BALB/c). Our data indicates that MuAstV has a wide geographical, institutional and host strain distribution. Comparison of the MuAstV RdRp sequences showed numerous mutations indicating ongoing viral divergence in different facilities. This study demonstrates the need for metagenomic screening of laboratory animals to identify adventitious infections that may affect experimental outcomes

    Combining computer vision and standardised protocols for improved measurement of live sea urchins for research and industry

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    To allow sea urchin aquaculture to achieve its intended scale, efficient and precise methods for measuring large numbers of urchins in commercial-scale operations are needed. Current protocols for measuring urchin test (shell) dimensions and mass are time-consuming and prone to high measurement error, thus inconvenient in research and impractical in a commercial context. This study investigates and compares various measurement methods with a newly developed computer vision approach developed in this study, to establish a single protocol using precise, efficient and accessible methodology for measuring live urchins. We show that urchin wet mass can vary up to 8.73% depending on time out of water; this is significantly reduced to an average of 0.1% change by allowing urchins to drip-dry for at least 90 s prior to weighing. We found the conventional vernier calliper method used to measure urchin dimensions to be both time-consuming and imprecise (mean coefficient of variation (CV) of 2.41% for Tripneustes gratilla). Conversely, the computer vision programme we developed measures with higher precision (mean CV of 1.55% for T. gratilla) and is considerably faster. The software uses a series of hue saturation value filters, edge detection algorithms and distortions to measure the diameter of the test (excluding spines) of multiple urchins at once. The software is open-source, and the protocol does not require specialised equipment (can be performed with a mobile phone camera). When the computer vision application is combined with the simple procedures described in this paper, to reduce measurement inaccuracies, urchin wet mass and diameter can be more efficiently and precisely determined. For a larger scale context, this software could easily be incorporated into various tools, such as a grading machine, to completely automate various farm processes. As such, this study has potential to assist urchin data collection in both research and commercial contexts

    Cross Domain IW Threats to SOF Maritime Missions: Implications for U.S. SOF

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    As cyber vulnerabilities proliferate with the expansion of connected devices, wherein security is often forsaken for ease of use, Special Operations Forces (SOF) cannot escape the obvious, massive risk that they are assuming by incorporating emerging technologies into their toolkits. This is especially true in the maritime sector where SOF operates nearshore in littoral zones. As SOF—in support to the U.S. Navy— increasingly operate in these contested maritime environments, they will gradually encounter more hostile actors looking to exploit digital vulnerabilities. As such, this monograph comes at a perfect time as the world becomes more interconnected but also more vulnerable

    Hybrid ports: the role of IoT and Cyber Security in the next decade

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    The next future will be played on a cyber level that imposes the need to merge “physical” with “digital in all fields”: phygital will be the future of current world, in many sectors, primarily in the transportation fields. Nowadays ports are doing several investment to provide technical solution to attract freight flows, are they ready to provide an answer to the cyber threat? This paper wish to present an overview of the main implications related to the cyber threats and maritime transports
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