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Martire, R. L., De Alwis, P., Äng, B. & Garme, K. (2017). Construction of a web-based questionnaire for longitudinal investigation of work exposure, musculoskeletal pain and performance impairments in high-performance marine craft populations. BMJ Open, 7(7), Article ID e016006.
Open this publication in new window or tab >>Construction of a web-based questionnaire for longitudinal investigation of work exposure, musculoskeletal pain and performance impairments in high-performance marine craft populations
2017 (English)In: BMJ Open, ISSN 2044-6055, E-ISSN 2044-6055, Vol. 7, no 7, article id e016006Article in journal (Refereed) Published
Abstract [en]

Objective High-performance marine craft personnel (HPMCP) are regularly exposed to vibration and repeated shock (VRS) levels exceeding maximum limitations stated by international legislation. Whereas such exposure reportedly is detrimental to health and performance, the epidemiological data necessary to link these adverse effects causally to VRS are not available in the scientific literature, and no suitable tools for acquiring such data exist. This study therefore constructed a questionnaire for longitudinal investigations in HPMCP. Methods A consensus panel defined content domains, identified relevant items and outlined a questionnaire. The relevance and simplicity of the questionnaire's content were then systematically assessed by expert raters in three consecutive stages, each followed by revisions. An item-level content validity index (I-CVI) was computed as the proportion of experts rating an item as relevant and simple, and a scale-level content validity index (S-CVI/Ave) as the average I-CVI across items. The thresholds for acceptable content validity were 0.78 and 0.90, respectively. Finally, a dynamic web version of the questionnaire was constructed and pilot tested over a 1-month period during a marine exercise in a study population sample of eight subjects, while accelerometers simultaneously quantified VRS exposure. Results Content domains were defined as work exposure, musculoskeletal pain and human performance, and items were selected to reflect these constructs. Ratings from nine experts yielded S-CVI/Ave of 0.97 and 1.00 for relevance and simplicity, respectively, and the pilot test suggested that responses were sensitive to change in acceleration and that the questionnaire, following some adjustments, was feasible for its intended purpose. Conclusions A dynamic web-based questionnaire for longitudinal survey of key variables in HPMCP was constructed. Expert ratings supported that the questionnaire content is relevant, simple and sufficiently comprehensive, and the pilot test suggested that the questionnaire is feasible for longitudinal measurements in the study population.

Place, publisher, year, edition, pages
BMJ Publishing Group, 2017
Keywords
content validity, epidemiology, fatigue, high-speed craft, whole-body vibration
National Category
Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-216314 (URN)10.1136/bmjopen-2017-016006 (DOI)000410203700143 ()2-s2.0-85025168880 (Scopus ID)
Note

QC 20171204

Available from: 2017-12-04 Created: 2017-12-04 Last updated: 2018-03-05Bibliographically approved
Razola, M., Olausson, K., Garme, K. & Rosén, A. (2016). On high-speed craft acceleration statistics. Ocean Engineering, 114, 115-133
Open this publication in new window or tab >>On high-speed craft acceleration statistics
2016 (English)In: Ocean Engineering, ISSN 0029-8018, E-ISSN 1873-5258, Vol. 114, p. 115-133Article in journal (Refereed) Published
Abstract [en]

Design and operation of high-speed planing craft is ruled by the hydrodynamic impact loads and the related craft responses occurring at violent wave encounters. Simulation, measurement and characterization of these loads and responses is however far from trivial. Hereby the general knowledge about these processes is actually rather limited and it is common to rely on simple semi-empirical formulas when designing and analyzing high-speed craft. This paper presents a unique set of impact acceleration data for a high-speed craft in waves, generated based on non-linear strip simulations. Methods and measures for statistical characterization of the acceleration process are established and evaluated, and by application of these methods on the simulation data a number of issues are clarified, for example: slamming time scales and selection of appropriate sampling rates and filtering levels; identification of peak values in acceleration signals; statistical distributions and convergence; and the relation between the statistical peak fraction averages that are commonly used as design parameters and the actual extreme values. The established methods and generated results form a valuable basis for setting up and analyzing high-speed craft experiments and simulations, and for validating and updating the prevailing semi-empirical methods.

Keywords
Slamming, High-speed craft statistics, Acceleration, Experiments, Simulations
National Category
Other Engineering and Technologies not elsewhere specified
Identifiers
urn:nbn:se:kth:diva-185379 (URN)10.1016/j.oceaneng.2016.01.004 (DOI)000372382000011 ()2-s2.0-84957010524 (Scopus ID)
Note

QC 20160418

Available from: 2016-04-18 Created: 2016-04-18 Last updated: 2017-11-30Bibliographically approved
Razola, M., Rosén, A. & Garme, K. (2014). Allen and Jones revisited. Ocean Engineering, 89, 119-133
Open this publication in new window or tab >>Allen and Jones revisited
2014 (English)In: Ocean Engineering, ISSN 0029-8018, E-ISSN 1873-5258, Vol. 89, p. 119-133Article in journal (Refereed) Published
Abstract [en]

In this paper the prevailing semi-empirical design method, used to predict design slamming pressures for high-speed craft and which is implemented in the scantling rules of the classification societies, is reconstructed and evaluated using numerical and experimental methodologies. It is shown that the present formulations are relevant in terms of the predicted pressures, but that there is room for improvements, particularly in relationship to modern high-speed craft structures. The design method is therefore modified in relationship to these observations using the numerical methodology, and it is concluded that these modifications result in significant improvements regarding the predicted design pressures. Finally a discussion on the analysis methodology; the formulation of lifetime design loads; and the structural loads developed due to the simplified design pressure model is presented.

Keywords
Local slamming, High-speed craft, Structural design, Experiments, Finite-element modeling
National Category
Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-156124 (URN)10.1016/j.oceaneng.2014.07.005 (DOI)000343690000011 ()2-s2.0-84906718892 (Scopus ID)
Note

QC 20141217

Available from: 2014-12-17 Created: 2014-11-21 Last updated: 2017-12-05Bibliographically approved
Razola, M., Rosén, A. & Garme, K. (2014). Experimental Evaluation of Slamming Pressure Models Used in Structural Design of High-Speed Craft. International Shipbuilding Progress, 61(1-2), 17-39
Open this publication in new window or tab >>Experimental Evaluation of Slamming Pressure Models Used in Structural Design of High-Speed Craft
2014 (English)In: International Shipbuilding Progress, ISSN 0020-868X, E-ISSN 1566-2829, Vol. 61, no 1-2, p. 17-39Article in journal (Refereed) Published
Abstract [en]

In this paper a methodology that enables detailed studies of the momentary slamming pressure distribution and the related structural loads is presented. The methodology involves pressure measurements, spatial and temporal pressure distribution reconstruction, and finite element analysis. Using a set of model experiments with a high-speed planing craft towed in irregular waves, the methodology is applied to evaluate different slamming pressure models regarding their ability to accurately represent the structure loads. The slamming equivalent uniform pressure model used in the prevailing semi-empirical design methods, and non-uniform time-dependent pressure models used in a method for direct calculation, are considered. It is concluded that for smaller structure members, typically found in densely spaced metal structures, the uniform pressure model performs well with respect to accurately representing the structure loads. However, for larger members found in modern sandwich structures, the underestimation of structure loads is significant, especially with respect to the shear forces. The non-uniform pressure modeling technique is concluded to be promising regarding its ability to accurately represent the structure loads, regardless of structure member size. The presented methodology is concluded to be a useful tool in further research regarding the evaluation and development of methods for high-speed craft structural design.

Keywords
Local slamming, structural loads, high-speed craft, experiments, finite element modeling
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:kth:diva-118808 (URN)10.3233/ISP-130104 (DOI)2-s2.0-84898473968 (Scopus ID)
Note

QC 20150624

Available from: 2013-02-28 Created: 2013-02-28 Last updated: 2017-12-06Bibliographically approved
Olausson, K. & Garme, K. (2014). Prediction and evaluation of working conditions on high-speed craft using suspension seat modelling. Journal of Engineering for the Maritime Environment (Part M), 229(3), 281-290
Open this publication in new window or tab >>Prediction and evaluation of working conditions on high-speed craft using suspension seat modelling
2014 (English)In: Journal of Engineering for the Maritime Environment (Part M), ISSN 1475-0902, E-ISSN 2041-3084, Vol. 229, no 3, p. 281-290Article in journal (Refereed) Published
Abstract [en]

Severe working conditions on board high-speed craft adversely affect not only the safety, health and performance of the crew but also the performance of the vessel as a technical system. Human factors–based ship design combined with appropriate vibration mitigation techniques and work routines for the crew can improve the working conditions and reduce the risks for performance degradation and adverse health effects. To enable development and use of such means, methods for prediction and evaluation of working conditions are needed for both existing high-speed craft and craft under design. This article presents a 2-degree-of-freedom seat model compatible with both measured and simulated input data. The interaction between seat and human is treated using the concept of apparent mass. The model is validated against experiment data collected on board a 10-m, 50-knot high-speed craft equipped with high-standard suspension seats. Evaluation measures defined in ISO 2631-1 and ISO 2631-5 are used to compare experiment data to modelled data. The seat model slightly overestimates the experiment S ed dose by a mean of 6.5% and underestimates the experiment vibration dose value (8 h) by 4.0%. It is concluded that model data correlate well with experiment data.

Keywords
Whole-body vibration, high-speed craft, working conditions, seat model, apparent mass, simulation, ergonomics/human factors, ISO 2631-1:1997, ISO 2631-4:2004, vibration dose
National Category
Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-159159 (URN)10.1177/1475090213515641 (DOI)000358451100005 ()2-s2.0-84937877525 (Scopus ID)
Note

QC 20150814

Available from: 2015-01-22 Created: 2015-01-22 Last updated: 2017-12-05Bibliographically approved
Garme, K., Rosén, A., Stenius, I. & Kuttenkeuler, J. (2014). Rough water performance of lightweight high-speed craft. Journal of Engineering for the Maritime Environment (Part M), 228(3), 293-301
Open this publication in new window or tab >>Rough water performance of lightweight high-speed craft
2014 (English)In: Journal of Engineering for the Maritime Environment (Part M), ISSN 1475-0902, E-ISSN 2041-3084, Vol. 228, no 3, p. 293-301Article in journal (Refereed) Published
Abstract [en]

Previous studies have shown how the use of composite materials and application of sophisticated design methods can give significantly lighter high-speed craft structures than what is normally achieved for traditional aluminium designs. A reduction in structural mass and a corresponding reduction in displacement improve the craft calm water performance but can be unfavourable regarding the rough water performance. Here, the rough water performance of two versions of a fast patrol vessel, one in aluminium and the other in carbon fibre sandwich, is studied with simplified semi-empirical methods and more advanced non-linear time domain simulations. In speeds up to 30 knots, the rough water performance of the two craft versions is found to be practically equal. At higher speeds, the lighter composite craft experiences higher vertical accelerations than the heavier aluminium craft, which implies less operational availability. Using trim ballast tanks, the rough water performance of the lighter craft is improved, and it is shown that the acceleration levels can be reduced and even lowered relative to the heavier aluminium craft. This means that the calm water advantages of a lighter composite vessel can be utilized with the same ride comfort and operational availability as for a heavier aluminium vessel.

Keywords
High-speed craft, energy efficiency, lightweight composite materials, vertical acceleration, rough water performance, bow tank, sustainability
National Category
Marine Engineering
Identifiers
urn:nbn:se:kth:diva-73402 (URN)10.1177/1475090212460456 (DOI)000340730100008 ()2-s2.0-84927596264 (Scopus ID)
Note

QC 20140919

Available from: 2012-02-02 Created: 2012-02-02 Last updated: 2017-12-08Bibliographically approved
Razola, M., Rosén, A., Garme, K. & Olausson, K. (2014). Towards Simulation-Based Design of High-Speed Craft. In: 4th Chesapeake Powerboat Symposium: . Paper presented at 4th Chesapeake Powerboat Symposium, Annapolis, Maryland, USA, June 2014.
Open this publication in new window or tab >>Towards Simulation-Based Design of High-Speed Craft
2014 (English)In: 4th Chesapeake Powerboat Symposium, 2014Conference paper, Published paper (Other academic)
Abstract [en]

The methods for structure design of high-speed craft available in the classification societies’ scantling codes and various standards are well established and easy to use. They are however limited in a number of aspects, for example regarding the consideration of the actual operational profile of the craft and the crew working conditions and safety. The drastic simplification of the slamming loads and the related uncertainties inherited in the semi-empirical background further limits the options for structure optimization. The alternative would be the establishment of direct calculation methods. The involved fluid-structure and craft-crew interactions, and the generally complex operation of high-speed craft, however imply great challenges. This paper reviews methods for time-domain simulation of craft motions, structure responses and crew environment for high-speed craft in irregular waves that are currently under development. An approach for using these methods for calculating extreme responses and analyzing crew and structure capacities with detailed consideration of the craft intended operation is outlined and the way forward for establishing a simulation based design approach is discussed.

National Category
Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-164392 (URN)
Conference
4th Chesapeake Powerboat Symposium, Annapolis, Maryland, USA, June 2014
Note

QC 20150416

Available from: 2015-04-16 Created: 2015-04-16 Last updated: 2016-06-13Bibliographically approved
Razola, M., Rosén, A., Garme, K. & Olausson, K. (2014). Towards simulation-based structural design of high-speed craft. Paper presented at 22 October 2014 through 24 October 2014. Transactions - Society of Naval Architects and Marine Engineers, 122, 479-492
Open this publication in new window or tab >>Towards simulation-based structural design of high-speed craft
2014 (English)In: Transactions - Society of Naval Architects and Marine Engineers, ISSN 0081-1661, Vol. 122, p. 479-492Article in journal (Refereed) Published
Abstract [en]

The methods for structure design of high-speed craft available in the class Wcation societies' scantling codes and various standards are well established and easy to use. They are however limited in a number of aspects, for example regarding the consideration of the actual operational profile of the craft and the crew working conditions and safety. The drastic simplf1cation of the slamming loads and the related uncertainties inherited in the semi-empirical background further limits the options for structure optimization. The alternative would be the establishment of direct calculation methods. The involved fluid-structure and craft-crew interactions, and the generally complex operation of high-speed craft, however imply great challenges. This paper reviews methods for time-domain simulation of craft motions, structure responses and crew environment for high-speed craft in irregular waves that are currently under development. An approach for using these methods for calculating extreme responses and analyzing crew and structure capacities with detailed consideration of the craft intended operation is outlined and the way forward for establishing a simulation based design approach is discussed.

Place, publisher, year, edition, pages
Society of Naval Architects and Marine Engineers, 2014
Keywords
Fluid structure interaction, Marine engineering, Slamming (ships), Structural optimization, Time domain analysis, Complex operations, Direct calculation, High speed crafts, Operational profile, Simulation-based designs, Structure optimization, Structure response, Time-domain simulations, Structural design
National Category
Other Civil Engineering
Identifiers
urn:nbn:se:kth:diva-181667 (URN)2-s2.0-84953234610 (Scopus ID)
Conference
22 October 2014 through 24 October 2014
Note

QC 20160316

Available from: 2016-03-16 Created: 2016-02-02 Last updated: 2017-11-30Bibliographically approved
Stenius, I., Garme, K., Hall Kihl, S. & Burman, M. (2014). Waterway 365: System Analysis of Challenges in Increased Urban Mobility by Utilization of the Water Ways. KTH Royal Institute of Technology
Open this publication in new window or tab >>Waterway 365: System Analysis of Challenges in Increased Urban Mobility by Utilization of the Water Ways
2014 (English)Report (Other (popular science, discussion, etc.))
Abstract [en]

Effective transport solutions for goods and people are crucial for the economic development of a region or city. In major cities worldwide there is a lack of capacity in the road and rail network resulting in high costs, only in Stockholm the cost of the overall shortcomings of commuting has been estimated to 6.3 billion SEK annually. The current trend is further increased congestions in major existing commut- ing routes (roads, rail networks and metro networks).

In coastal cities like Stockholm, Gothenburg or Copenhagen however, there are inland waterways that would enable shorter and faster commuting routes if efficient land-sea based transportation systems are implemented. In addition the waterway constitutes an opportunity to create new city space, add transport capacity, offer new communication paths, change the transport flow and level off the pres- sure on the present transport system.

The waterways and parts of the road network are existing infrastructure resources that may be used to contribute to more sustainable travel patterns, reduce congestion on main commuting corridors, in- crease capacity and the traffic system's resilience through new travel relationships, travel patterns and synergies with bicycle and city logistics.

The aim of this work is to identify the most relevant research topics and key performance parameters for personal transport and city logistics systems on the waterways in urban environments for year- round service. The long-term goal is to identify transport systems and technical solutions for the wa- terways that can be scaled and adapted to urban environments around the world and that complement the land-based transport systems in order to achieve an over-all sustainable urban mobility.

This work focuses on a systems engineering perspective and includes identification of system bounda- ries and interfaces to other public transport, infrastructure nodes, system service and maintenance and measurement of sustainability and service improvement targets. The aim is to develop a base for a system that can be scaled and adapted to urban environments around the world - like how road or rail- based mass transit systems today are built up from more or less standard units, not to design a public transport solution for a specific city, route or line. The focus is on realistic solutions that are both achievable from a cost perspective and attractive to passengers during 365 days a year. New concepts, ranging from small single person commuters up to large public transport systems, are to be explored and evaluated and key technical challenges identified and targeted.

The research initiative Waterway 365 was initiated by The Royal Institute of Technology (KTH) and Vattenbussen AB with support from the Swedish Maritime Administration (Proj. no: 15041-0). 

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2014. p. 50
Series
TRITA-AVE, ISSN 1651-7660 ; 2014-13
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:kth:diva-187056 (URN)978-91-7595-161-4 (ISBN)
Note

QC 20160518

Available from: 2016-05-16 Created: 2016-05-16 Last updated: 2016-05-18Bibliographically approved
Olausson, K. & Garme, K. (2013). Simulation-based assessment of HSC crew exposure to vibration and shock. In: FAST 2013 - 12th International Conference on Fast Sea Transportation: . Paper presented at 12th International Conference on Fast Sea Transportation, FAST 2013, 2 December 2013 through 5 December 2013, Amsterdam, Netherlands. FAST 2013 Secretariat
Open this publication in new window or tab >>Simulation-based assessment of HSC crew exposure to vibration and shock
2013 (English)In: FAST 2013 - 12th International Conference on Fast Sea Transportation, FAST 2013 Secretariat , 2013Conference paper, Published paper (Refereed)
Abstract [en]

A simulation-based method for assessment of HSC crew vibration and shock exposure is presented. The simulation scheme includes three modules: Craft response module, Seat response module and Human exposure evaluation module. The first module computes the craft acceleration in the time-domain by a non-linear strip method and delivers input to the second module, where a crew seat model determines the human acceleration exposure time history. The crew's acceleration exposure is assessed in the third module, which includes a strategy to describe the operational profile. The human vibration exposure is evaluated using international standards (ISO 2631-1, ISO 2631-5). In addition, statistical extreme value analyses are used to evaluate the human exposure to shock. The potential to reduce the vibration and shock level is discussed and exemplified using the simulation-based evaluation method to analyse how different seat designs and running attitudes influence the crew vibration exposure.

Place, publisher, year, edition, pages
FAST 2013 Secretariat, 2013
Keywords
Civil engineering, Transportation, Exposure-time, Extreme value analysis, Human exposures, Human vibrations, International standards, Operational profile, Simulation-based method, Vibration exposure, Time domain analysis
National Category
Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-151005 (URN)2-s2.0-84904662073 (Scopus ID)
Conference
12th International Conference on Fast Sea Transportation, FAST 2013, 2 December 2013 through 5 December 2013, Amsterdam, Netherlands
Note

QC 20140912

Available from: 2014-09-12 Created: 2014-09-12 Last updated: 2015-01-26Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-9110-9401

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