Containerfartens historiske udvikling bliver i litteraturen beskrevet som en revolution og en transformation af den internationale shippingbranche. De teknologiske og organisatoriske forandringer af livet til søs som fulgte med containerfarten har tilsvarende medført en forandring af maritime kulturer og en udfordring af de søfarendes identiteter.
Denne afhandling handler om danske containersøfolks erindringer, fortidsbrug og identitetskonstruktioner og undersøger, hvordan søfolkene fortæller sig selv i relation til deres levede erfaringer i containerfarten. Jeg analyserer i afhandlingen søfolkenes retrospektive fortidsfortolkninger som en måde at nærme mig en forståelse af de forandrede sømandsidentiteter.
Analytisk anlægger afhandlingen et subjektperspektiv, som anser fortiden for nærværende og åben i de mundtlige fortællingers fortolkninger og meningsforhandlinger af fortidens erfaringer. Jeg anskuer den narrative konstruktion af den personlige, autobiografiske, historie som identitetsdannende fortidsbrug, der udtrykker fortællerens subjektivitet. Med en erindringshistorisk tilgang til søfolkenes mundtlige fortællinger undersøger jeg, hvordan vi mennesker forstår os selv gennem de historier, vi fortæller om os selv.
Afhandlingen bygger empirisk på en række dybdegående oral history interviews med danske søfolk, der alle har erfaring inden for den internationale containerfart.
I afhandlingens analyser, viser jeg, hvordan søfolkene retfærdiggør og legitimerer deres valg om i første omgang at blive søfolk og senere at arbejde ombord på containerskibe. Jeg viser, hvordan søfolkene narrativt forhandler forskellige former for erfaret meningstab og aktivt tilskriver arbejdet og fællesskabet ombord på skibene en ny og brugbar mening. Jeg viser samtidig, hvordan den personlige historie konstrueres i dialog med kulturelt dominerende forestillinger og fortællinger. Sådanne forestillinger og fortællinger tilbyder den enkelte fortæller et tilgængeligt sprog at udtrykke sine personlige erfaringer i, men kan også virke begrænsende, hvis fortællerens erfaringer og forståelser ikke passer ind i de dominerende billeder. I sådanne tilfælde kan der opstå, hvad afhandlingen kalder en form for narrativt ubehag (discomposure), der kommer til udtryk som frustration og brud i fortællingens narrative sammenhæng.
Som en gennemgående metodisk pointe viser afhandlingen, hvordan interviewets intersubjektivitet er med til at forme den historie, som fortælles. Det personlige møde mellem fortæller og historiker og interviewets kulturelle kontekster indvirker på forskellig vis på den konstruerede historie. Fremfor at hævde en neutral og objektiv interviewsituation, tager afhandlingen i stedet konsekvensen af denne intersubjektivitet og skriver det konkrete møde mellem søfolkene som fortællere og mig som interviewer ind som en integreret del af den historiske fremstilling. Dette er både et narrativt greb og et metodisk valg, der skal sikre transparens ved at give læseren indblik i, hvordan historierne og mine tolkninger er blevet til.
Afhandlingen yder med sin tilgang og sine analyser flere bidrag til den eksisterende litteratur. Gennem de personlige fortællinger får vi større indsigt i søfolkenes levede liv og deres erfaringer med containerfartens historiske udvikling. Afhandlingen giver et menneskeligt perspektiv på historien om den internationale containerfart, der bidrager til vores viden om udviklingens identitetsmæssige betydning for de mænd og kvinder, som gennemlevede de historiske forandringer ude ombord på skibene.
Afhandlingen er en virksomhedshistorie, der tager oral history alvorligt både som forskningsfelt, metode og genre. Afhandlingen bidrager med sin erindringshistoriske tilgang til oral history til den fornyede samtale mellem forskningsfelterne oral history og virksomhedshistorie. Afhandlingen bringer metodiske og teoretiske indsigter fra den erindringshistoriske tradition ind i virksomhedshistorie og viser gennem sin egen narrative stil potentialet i en historieformidling, der sætter subjektivitet og erindring i centrum af sin analyse. Dermed bidrager afhandlingen også til den narrative vending inden for virksomhedshistorie ved ikke kun at anlægge et narrativt blik på de danske søfolks fortællinger men ved også at tage sig selv alvorligt som narrativ konstruktion.
Wind propulsion systems (WPS) for commercial ships can be a key ingredient to achieving the IMO green targets. Most WPS installations will operate in conjunction with propellers and marine engines in a hybrid mode, which will affect their performance. The present paper presents the development of a generic, fast, and easy tool to predict the propeller and engine performance variation, along with the cost, as a function of the wind power installed in two operation conditions: fixed ship speed and constant shaft speed. Specific focus is directed toward showing generic trends and trade-offs that inform economic decision-making. To this end, a key feature of the presented work is the ability to assess the cost–benefit of both controllable pitch propellers and fixed pitch propellers (CPPs and FPPs). This provides advice on when, in terms of WPS installation size, it is worthwhile to install which kind of propeller. CPPs are found to be more suitable for newly built wind-powered ships (>70% wind power), while a conventional FPP is satisfactory for wind-assisted ships (<70% wind power) and retrofitted installations. The results for a 91,373 GT bulk carrier showed that a WPS unloads the propeller and the engine, which leads to an increase in the propulsive efficiency and a detrimental rise of the engine specific fuel oil consumption. However, propeller gains are found to be greater than engine losses, which result in extra savings. Thus, not only does a WPS save fuel and corresponding pollutant emissions, but it also increases the entire propulsive efficiency.
In this paper, we study a problem that integrates the vessel scheduling problem with the berth allocation into a collaborative problem denoted as the multi-port continuous berth allocation problem (MCBAP). This problem optimizes the berth allocation of a set of ships simultaneously in multiple ports while also considering the sailing speed of ships between ports. Due to the highly combinatorial character of the problem, exact methods struggle to scale to large-size instances, which points to exploring heuristic methods. We present a mixed-integer problem formulation for the MCBAP and introduce an adaptive large neighborhood search (ALNS) algorithm enhanced with a local search procedure to solve it. The computational results highlight the method's suitability for larger instances by providing high-quality solutions in short computational times. Practical insights indicate that the carriers’ and terminal operators’ operational costs are impacted in different ways by fuel prices, external ships at port, and the modeling of a continuous quay.
Using evidence from 25,250 records of vessels entering and clearing the rivers of the Chesapeake Bay, this article demonstrates that intercolonial trading captains and crews significantly reduced the number of days their vessels spent in port in Virginia between 1698 and 1766. This contraction reflected a quantifying ethos in shipping that emerged during the early age of sail as the result of mutually reinforcing legal requirements and management practices. Responding to these productivity pressures, captains embraced practices that limited sailors’ freedom and turned to enslaved sailors to guarantee their maritime labor force. Embracing unfreedom aided captains to realize the dispatch goals that helped guarantee their investors’ returns.
A practical estimation methodology of the mean added resistance in irregular waves is shown, and the present paper provides statistical analyses of estimates for ships in actual conditions. The study merges telemetry data of more than 200 in-service container vessels with ocean re-analysis data from ERA5. Theoretical estimates relying on spectral calculations of added resistance are made for both long- and short-crested waves and are based on a combination of a parametric expression for the wave spectrum and a semi-empirical formula for the added resistance transfer function. The theoretical estimates are compared to predictions from an indirect calculation of added resistance relying on shaft power measurements and empirical estimates of the remaining resistance components. Overall, the comparison reveals a bias in bow oblique waves and higher sea states of the spectral estimates as well as the large variance of the empirically derived predictions — particularly in beam-to-following waves. One of the study’s main findings, confirming previous studies but based on a much larger dataset than in earlier similar studies, is that added resistance assessment based on in-service data is complex due to significant associated uncertainties.
Ship engines are subject to a very demanding work environment, where maximum availability is a must. In this project we look at different operational variables of a marine engine from large cargo ships, with the aim of detecting and trending damage onset on different engine sub-components. This information can be used by owners to expedite O&M interventions and maximize ship availability.
With the rise of ‘new’ state capitalisms, control over transport infrastructure has returned to the forefront of competition in the global economy. This article investigates how different state capitalisms interact to enable economic developments in ports. It tracks the relationship between state-owned firms in the shipping and ports sectors through a case study of the port of Valencia in Spain and COSCO shipping group. The article identifies state capitalisms as variegated and relational to analyze the ways in which qualitatively different state capitalist dynamics interact at different scales. The article identifies two state capitalist dynamics which have been dominant in determining relations between Spanish and Chinese state capitalisms: 1) A commercial dynamic of maximizing Spanish ports profits by establishing new relationships with Chinese firms; and 2) an expansionary dynamic of increasing market share of Chinese state-owned firms in European shipping markets. These two dynamics are synergistic and have contributed to the competitiveness of Spanish ports and Chinese shipping firms by providing new capital to the port of Valencia and expanding the port's profile as a hub in the eastern Mediterranean, while also further solidifying COSCO's position in European shipping markets and its internalization and vertical integration strateg
The technician routing and scheduling problem (TRSP) consists of technicians serving tasks subject to qualifications, time constraints and routing costs. In the literature, the TRSP is solved either to provide actual technician plans or for performing what-if analyses on different TRSP scenarios. We present a method for building optimal TRSP scenarios, e.g., how many technicians to employ, which technician qualifications to upgrade, etc. The scenarios are built such that the combined TRSP costs (OPEX) and investment costs (CAPEX) are minimized. Using a holistic approach we can generate scenarios that would not have been found by studying the investments individually. The proposed method consists of a matheuristic based on column generation. To reduce computational time, the routing costs of a technician are approximated. The proposed method is evaluated on data from the literature and on real-life data from a telecommunication company. The evaluation shows that the proposed method successfully suggests attractive scenarios. The method especially excels in ensuring that more tasks are serviced but also reduces travel time with around 16% in the real-life instance. We believe that the proposed method could constitute an important strategic tool in field service companies and we propose future research directions to further its applicability.
In this article, the author describes how the creation of the Danish maritime museums in 1915 and 2013 – both generously funded by maritime foundations and actors – was perceived by the shipping industry as initiatives that would help market the industry in the eyes of the public. He argues more generally that national maritime museums constitute focal points for disseminating narratives that legitimate maritime activities and establish these activities as symbols of national identities. It is suggested that maritime historians, curators and scholars reflect on the relationship between maritime industry actors and museum exhibition narratives, and consider the interests and capital that potentially underpin museums’ and curators’ decisions.
With the current revolution in Shipping 4.0, a tremendous amount of data is accumulated during vessel operations.
Data quality (DQ) is becoming more and more important for the further digitalization and effective decision-making
in shipping industry. In this study, a practical DQ assessment method for raw data in vessel operations is proposed.
In this method, specific data categories and data dimensions are developed based on engineering practice and existing
literature. Concrete validation rules are then formed, which can be used to properly divide raw datasets. Afterwards,
a scoring method is used for the assessment of the data quality. Three levels, namely good, warning and alarm,
are adopted to reflect the final data quality. The root causes of bad data quality could be revealed once the internal
dependency among rules has been built, which will facilitate the further improvement of DQ in practice. A case study
based on the datasets from a Danish shipping company is conducted, where the DQ variation is monitored, assessed
and compared. The results indicate that the proposed method is effective to help shipping industry improve the quality
of raw data in practice. This innovation research can facilitate shipping industry to set a solid foundation at the early
stage of their digitalization journeys.