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Advancing safety in autonomous shipping through modern hazard analysis methods - A System-Theoretic Approach
No full textThe maritime industry is currently undergoing a substantial transformation towards autonomous shipping, where human involvement in operational activities is diminishing, emphasizing safety and efficiency improvements. This transition, however, introduces new safety challenges that necessitate rigorous risk assessment and innovative safety frameworks.
This thesis commences with an exploration of the historical development of risk, safety, and reliability considerations in autonomous shipping through a bibliometric review. Additionally, the future research directions and the potential risk assessment methods adequate for the complex autonomous ships are analysed.
System Theoretic Process Analysis (STPA) is a key focus of this study. The thesis provides and investigate a model of the STPA organizational control structure within the maritime operational paradigm, seeking to reveal safety challenges of the transition to autonomy. An essential aspect of the work presented in this thesis involves integrating STPA with established marine risk assessment procedures, utilizing Bayesian Networks to quantify risks. The proposed framework scrutinizes the selection of Risk Control Options (RCOs) within Marine Risk Assessment (MRA) process and examines the potential incorporation of STPA-BN within the Formal Safety Assessment (FSA) process.
Drawing upon conventional maritime practices, the thesis offers an approach to develop safety control structure of autonomous ship systems and provides an analysis of the control structure components of Autonomous Navigation Systems (ANS). Hence identifies unique safety challenges posed by these innovations.
In summary, this doctoral thesis serves as a technical compass guiding the maritime industry towards enhanced safety in the age of autonomous shipping. By leveraging modern hazard analysis methods, particularly STPA, and integrating them into established risk assessment practices, this research seeks to catalyse a shift towards advanced system-theoretic risk assessment processes in the maritime industry, acknowledging the evolving regulatory landscape and the complexity of the challenges at hand
Ship operational performance modelling for voyage optimization through fuel consumption minimization
Get PDFMaritime image-based weather classification to evaluate the object detection performance
No full textA preliminary analysis of the impact of autonomous maritime surface ships in marine technology education
Get PDFThis thesis is written to analyse the development of Maritime Autonomous Surface Ship its impact on technology and trends in shipping. The concept of Maritime Autonomous Surface Ship is introduced and projects that explore the concept and one which has been developed is reviewed. A review of Maritime Autonomous Surface Ships in Maritime Education and Training for seafarers is conducted to see the results of these studies.
The author analyses the courses taught at Aalto University to see how much of the Autonomous Ship concept is incorporated in the education of Naval Architecture students. A study of various courses offered at other universities is conducted and the technologies that are implemented in Maritime Autonomous Surface Ships are analysed. An evaluation of various education techniques is conducted to possibly formulate a plan to incorporate these techniques in the education of students of Marine and Arctic Technology at Aalto University.
Following the research, the viability of Maritime Autonomous Surface Ships to be incorporated is discussed and implementation of techniques in education are shown. A plan is formulated to see which technologies can be incorporated in which courses and a timeline is formulated to incorporate Maritime Autonomous Surface Ships in Marine and Artic Technology at Aalto University.
The author concludes that it is viable to incorporate Maritime Autonomous Surface Ships in education of Naval Architecture students by following the plan given
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Riskianalyysi autonomisen laivan navigointijärjestelmälle
No full textThe maritime industry is undergoing a thorough reformation in multiple domains, one of which is ship navigation and operation. Significant efforts have recently been targeted towards the research and development of Marine Autonomous Surface Ships (MASS). Majority of the maritime accidents are caused by erroneous human action, and introducing autonomous capabilities to ships is aiming to decrease the number of human-caused accidents and thus increase the safety of maritime operations. However, the safety of the MASS has to be demonstrated and found to be acceptable prior to the widespread adoption of the technology. The systems enabling autonomous navigation are complex, cyber-physical systems, and the nature of the risks related to these systems might differ significantly from the traditional maritime risks. Identifying and mitigating these risks prior to applying the systems to real-world operations is essential.
This thesis aims to assess the risk levels of a currently developed Autonomous Navigation System (ANS), and based on the results, provide guidelines for the system development going forward. System-Theoretic Process Analysis (STPA) and Bayesian Network (BN) were chosen as the methods for identifying and quantifying the risks, respectively.
The results provide a holistic view of the underlying risks in the ANS system. Specific causes were identified for each risk, and safety controls were generated for each specific cause. The quantified risk levels of each loss event were computed, and the loss of reputation was found to be the most probable loss. In addition to the risk levels, the relative influence of each causal factor was identified, and guidance for the system development was provided based on this information.
To the author’s best knowledge, a risk analysis for this type of technology at this phase of development was yet to be done in academia. Thus, this thesis greatly contributes to the risk analysis of autonomous ships and provides guidance to decision-makers and system developers alike.Merenkulkualalla on tapahtumassa merkittäviä mullistuksia, joista yksi liittyy laivojen navigointiin. Autonomisia laivoja on tutkittu ja kehitetty mittavin resurssein viimeisten kymmenen vuoden aikana, niin yksityisten kuin julkistenkin organisaatioiden toimesta. Tällä hetkellä suurin osa meriliikenteessä tapahtuvista onnettomuuksista aiheutuu ihmisten tekemistä virheistä, ja autonomisten laivojen tavoite on vähentää näitä onnettomuuksia ja täten parantaa merenkulun turvallisuutta kaikkien osapuolien näkökulmasta. On kuitenkin selvää, että ennen autonomisten laivojen laajempaa käyttöönottoa, on niiden turvallisuutta tutkittava. Laivojen autonomiseen navigointiin liittyvät järjestelmät ovat erittäin monimutkaisia ohjelmistotekniikka, fyysisiä laitteita sekä ihmisiä yhdistäviä järjestelmiä. Näihin järjestelmiin liittyvät riskit voivat poiketa merkittävästi perinteisistä merenkulun riskeistä, ja näiden riskien tunnistaminen ja ennaltaehkäiseminen on ensiarvoisen tärkeää.
Tämän diplomityön tavoite on arvioida kehitteillä olevan autonomisen navigointijärjestelmän riskejä, ja tulosten perusteella pyrkiä ohjaamaan tuotekehitystä turvallisemman ratkaisun suuntaan. Riskianalyysimetodeiksi valittiin järjestelmäteoreettinen prosessianalyysi (STPA) sekä bayesilainen verkko (BN).
Tutkimuksen tulokset antavat kattavan käsityksen järjestelmään liittyvistä riskeistä sekä niiden todennäköisyyksistä. Löydetyille riskeille tunnistettiin tarkat syytekijät, ja näistä jokaiselle kehitettiin turvallisuusvaatimukset. Bayesilaista verkkoa hyödynnettiin myös selvittämään syytekijöiden suhteellista vaikuttavuutta. Tämän tiedon avulla pystyttiin ohjaamaan tuotekehitystä turvallisempaan ratkaisuun mahdollisimman tehokkaasti.
Kirjoittajan tiedon mukaan riskianalyysiä vastaavassa kehitysvaiheessa olevalle autonomiselle navigointijärjestelmälle ei ole toistaiseksi tehty. Täten tämä diplomityö tuottaa arvokasta informaatiota niin merenkulkualan päätöksentekijöille kuin vastaavia järjestelmiä kehittäville tahoille
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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