International Shipbuilding Progress - Volume 71, issue 1

Authors: Wellens, Peter

Article Type: Editorial

DOI: 10.3233/ISP-249001

Citation: International Shipbuilding Progress, vol. 71, no. 1, pp. 1-2, 2024

Authors: Alblas, Gerrit | Pruijn, Jeroen

Article Type: Review Article

Abstract: In the fiercely competitive shipbuilding industry, precise cost estimates must be considered as they serve as a critical input for determining market prices effectively and ensuring a small profit for the shipyard. In Western Europe, where most projects are Engineering-To-Order (ETO), cost estimations are extra challenging, due to lack of similarity between projects. On top of this, cost estimations are becoming increasingly difficult in a market confronted by mounting challenges related to safety regulations, cost-effectiveness, and the pressing need to address energy conservation and environmental protection. New technologies introduce changes in nearly all aspects of shipbuilding design and construction. This …article conducts a literature review, to present the state-of-the-art methods for estimating man-hours, explicitly focusing on man-hours for shipyard production, excluding overhead costs and challenges the suitability of existing systems for ETO and especially for the changes caused to ships by the energy transition. An indication is given of the practicality of each method as outlined in the literature. A solution direction, incorporating the construction process, is proposed to improve cost estimations for ETO projects in pre-contract phase. Show more

Keywords: Cost estimation method, Engineering-To-Order, pre-contract

DOI: 10.3233/ISP-230009

Citation: International Shipbuilding Progress, vol. 71, no. 1, pp. 3-28, 2024

Authors: Stopa, Michał

Article Type: Research Article

Abstract: Background: Merchant ships, despite huge technological progress, are still operated by qualified navigators. According to ergonomics principles, human is a part of the whole system and is affected by the surrounding environment. Objective: The purpose of the paper was to assess the ergonomic awareness of professional navigators, to understand their expectations towards navigation bridges and to check if they obtain enough support from their workplace. Methods: A special questionnaire was developed and 200 responses were obtained from seafarers with license of Officer Of the Watch or higher. Statistical analysis were carried out to find out relationships …and differences between answers and groups of respondents. Results: Improper ergonomics and less than optimal working conditions were not isolated incidents and occurred to be rather common problem of the industry. The results suggest that ergonomic awareness is at relatively high level, however this knowledge is frequently not used in practice. Conclusions: Poor design and lack of proper ergonomics training might contribute to commonly experienced signs of fatigue, pain episodes and therefore reduced performance of seafarers. Navigators find ergonomics important, however navigation bridges often do not meet ergonomics and comfort standards, therefore there is still a room for improvement in this area. Show more

Keywords: Bridge ergonomics, ergonomic awareness, bridge design

DOI: 10.3233/ISP-230014

Citation: International Shipbuilding Progress, vol. 71, no. 1, pp. 29-47, 2024

Authors: Tonelli, Roberto | Vogels, Roderik

Article Type: Research Article

Abstract: This paper presents the mathematical model used in MARIN’s time domain software to describe the hydrodynamic loads excited by a rudder. The paper provides a detailed description of the mathematical model and its theory, along with highlighting the novel features that have been added to extend the model to four quadrants operations. Furthermore, the paper compares the mathematical model with experiments, showcasing the model’s capabilities and shortcomings. For this comparison, a spade rudder behind the KRISO Container Ship with and without a propeller upstream has been used as a case study to illustrate how the model performs in practice.

Keywords: Rudder, mathematical model, manoeuvring

DOI: 10.3233/ISP-240004

Citation: International Shipbuilding Progress, vol. 71, no. 1, pp. 49-86, 2024