Abstracts of the FSEG external publications
A Systematic Methodology to assess the Impact of Human Factors in Ship Design
S J Deere, E R Galea, P J Lawrence
Abstract:
Evaluating ship layout for human factors (HF) issues using simulation software
such as maritimeEXODUS can be a long and complex process. The analysis requires
the identification of relevant evaluation scenarios, encompassing evacuation and
normal operations, the development of appropriate measures which can be used to
gauge the performance of crew and vessel and finally, the interpretation of
considerable simulation data. Currently, the only agreed guidelines for
evaluating HFs performance of ship design relate to evacuation and so
conclusions drawn concerning the overall suitability of a ship design by one
naval architect can be quite different from those of another. The complexity of
the task grows as the size and complexity of the vessel increases and as the
number and type of evaluation scenarios considered increases. Equally, it can be
extremely difficult for fleet operators to set HFs design objectives for new
vessel concepts. The challenge for naval architects is to develop a procedure
that allows both accurate and rapid assessment of HFs issues associated with
vessel layout and crew operating procedures. In this paper we present a
systematic and transparent methodology for assessing the HF performance of ship
design which is both discriminating and diagnostic. The methodology is
demonstrated using two variants of a hypothetical naval ship.
Simulation of ship evacuation and passenger circulation
Fernando Caldeira-Saraiva, Jenny Gyngell, Rob Wheeler, Edwin Galea, Andrew Carran, Kaj Johansson, Bob Rutherford, António J Simoes Ré
Abstract
This paper describes work carried out in the FIRE EXIT research project. FIRE
EXIT aims to develop an Evacuation Simulator, capable of addressing issues of
mustering, ship motions, fire and abandonment. In achieving these aims, FIRE
EXIT took as its starting point the state-of-the-art in ship evacuation
simulation (the maritimeEXODUS software), fire simulation (the SMARTFIRE
software) and large-scale experimental facilities (the SHEBA facility). It then
significantly enhanced these capabilities. A number of new technologies have
been developed in achieving these objectives. The innovations include directly
linking CFD fire simulation with evacuation and abandonment software and
automatic data transfer from concept design software allowing rapid generation
of ship simulation models. Software usability was augmented by a module for
interpretation of evacuation software output. Enhancements to a ship evacuation
testing rig have resulted in a unique facility, capable of providing passenger
movement data for realistic evacuation scenarios and large scale tests have
provided meaningful data for the evacuation simulation.
Keywords: Simulation, Evacuation, Safety Case.
Integrated fire and evacuation in maritime environment
E R Galea, P Lawrence, S Gwynne, G Sharp, N Hurst, Z Wang and J Ewer
Abstract
When designing a new passenger ship or modifying an existing design, how do we
ensure that the proposed design and crew emergency procedures are safe from an
evacuation resulting from fire or other incident? In the wake of major maritime
disasters such as the Scandinavian Star, Herald of Free Enterprise, Estonia, and
in light of the growth in the numbers of high density, high-speed ferries and
large capacity cruise ships, issues concerning the evacuation of passengers and
crew at sea are receiving renewed interest. Fire and evacuation models with
features such as the ability to realistically simulate the spread of fire and
fire suppression systems and the human response to fire as well as the
capability to model human performance in heeled orientations linked to a virtual
reality environment that produces realistic visualisations of the modelled
scenarios are now available and can be used to aid the engineer in assessing
ship design and procedures. This paper describes the maritimeEXODUS ship
evacuation and the SMARTFIRE fire simulation model and provides an example
application demonstrating the use of the models in performing fire and
evacuation analysis for a large passenger ship partially based on the
requirements of MSC circular 1033. The fire simulations include the action of a
water mist system.
Keywords: Fire Simulation, Evacuation Simulation, Computational Fluid Dynamics,
Ship Evacuation, Water Mist.
A Preliminary Investigation of the Evacuation of the WTC North Tower using Computer Simulation
E Galea, P Lawrence, S Blake, S Gwynne, H Westeng
Abstract:
This paper concerns a preliminary numerical simulation study of the evacuation of the World Trade Centre North Tower on 11 September 2001 using the buildingEXODUS evacuation simulation software. The analysis makes use of response time data derived from a study of survivor accounts appearing in the public domain. While exact geometric details of the building were not available for this study, the building geometry was approximated from descriptions available in the public domain. The study attempts to reproduce the events of 11 September 2001 and pursue several ‘what if’ questions concerning the evacuation. In particular, the study explores the likely outcome had a single staircase survived intact from top to bottom.
An Analysis of Human Behaviour during the WTC Disaster of 11 September 2001 Based on Published Survivor Accounts
S Blake, E Galea, H Westeng, A Dixon
Abstract:
This paper presents an analysis of survivor experiences from the World Trade Centre (WTC) evacuation of 11 September 2001. The experiences were collected from published accounts appearing in the print and electronic mass media and are stored in a relational database specifically developed for this purpose.
The Representation of Occupant Sensitivity to Irritant Fire Gases, Within Evacuation Analysis
E Galea, S Gwynne, P Lawrence, Z Wang
Abstract:
In this paper we present an extension toevacuation modelling through the introduction of occupant sensitivity to the irritant fire gases: HCl, HBr, HF, SO2, NO2, Acrolein and Formaldehyde. In addition, a further advance to computational fire engineering is briefly described through the direct coupling of evacuation simulation with CFD based fire modelling software tools. The combined modelling approach is then demonstrated through an application involving a fire producing both narcotic and irritant fire gases. The analysis involves a combination of experimental fire data, CFD fire simulation and evacuation simulation.
The Simulation of Fire and Evacuation at Sea
E Galea, A Grandison, L Filippidis, S Gwynne, J Ewer, P Lawrence
Abstract:
In this paper we examine how sophisticated fire and evacuation analysis can be coupled to provide detailed insight into the performance of both man and vessel under emergency conditions involving fire at sea. In these calculations, the output from the SMARTFIRE fire simulation is fed directly into the maritimeEXODUS ship evacuation simulator, exposing the virtual passengers and crew to the evolving fire conditions. The insight gained from such an interactive simulation can be used to investigate the success of both the vessel physical layout and the evacuation procedures implemented on board. The analysis can also be used to suggest cost efficient solutions to identified shortcomings in both vessel architecture and procedures.
Group Solvers: A Means of
Reducing Run-Times and Memory Overheads for CFD-
Based Fire Simulation Software
N Hurst-Clark, J Ewer, A Grandison, E Ed Galea
Abstract:
The Group Solver technique is an adaptation of commonly used iterative solvers in CFD-based fire simulation software that attempts to reduce the high computational costs normally associated with this approach. The principle behind the Group Solver is to characterise the control volumes of any large scale geometry to allow control volume groupings based on processing requirements. In this way computational effort can be targeted to groups of cells that require the computational effort, rather than applying the same effort to every cell in the domain. In large scale problems, Group Solver techniques can reduce run times by at least 18%.
CFD Fire Simulation of the Swissair Flight 111 In-Flight Fire
F Jia, M Patel, E Galea
Abstract:
At 8.18pm on 2 September 1998, Swissair Flight 111 (SR 111) took off from New York’s JFK airport bound for Geneva, Switzerland. Tragically, the MD-11 aircraft never arrived. According to the crash investigation report, published on 27 March 2003, electrical arcing in the ceiling void cabling was the most likely cause of the fire that brought down the aircraft. No one on board was aware of the disaster unfolding in the ceiling of the aircraft and, when a strange odour entered the cockpit, the pilots thought it was a problem with the air-conditioning system. Twenty minutes later, Swissair Flight 111 plunged into the Atlantic Ocean five nautical miles southwest of Peggy’s Cove, Nova Scotia, with the loss of all 229 lives on board.
In this paper, the Computational Fluid Dynamics (CFD) analysis of the in-flight fire that brought down SR 111 is described. Reconstruction of the wreckage disclosed that the fire pattern was extensive and complex in nature. The fire damage created significant challenges to identify the origin of the fire and to appropriately explain the heat damage observed. The SMARTFIRE CFD software was used to predict the “possible” behaviour of airflow as well as the spread of fire and smoke within SR 111. The main aims of the CFD analysis were to develop a better understanding of the possible effects, or lack thereof, of numerous variables relating to the in-flight fire. Possible fire and smoke spread scenarios were studied to see what the associated outcomes would be. This assisted investigators at Transportation Safety Board (TSB) of Canada, Fire & Explosion Group, in assessing fire dynamics for cause and origin determination.
Predicting Hydrogen Chloride Concentrations in Fire Enclosures using a Deposition Model Linked to Field Fire Models
Z Wang, F Jia, E Galea, J Ewer.
Abstract:
The concentrations of hydrogen chloride (HCL), within fire enclosures, decay due to absorption on to solid surfaces. This paper describes a deposition model [1], typically used in zone models, that has been modified and applied to the SMARTFIRE field fire model in order to predict the decay of HCL in fire enclosures. When compared to the deposition model in [1], this modified model still uses empirical formulas, but the HCL deposition mechanisms have been simplified from three processes to two, resulting in one differential equation – for the calculation of HCL density on the wall surfaces – omitted. The effect of HCL flux to the wall boundary on the time to reach equilibrium (i.e. for the wall surface HCL density to rise and reach equilibrium) is addressed in this modified model. Simulation results using the modified HCL deposition model are compared with data from room-corridor and small-scale chamber PVC fires.
A New Approach to the Simulation of Gaseous Combustion and its Application to Several Test Fire Scenarios
J Zhang, F Jia, E Galea, J Ewer.
Abstract:
In this paper, a new gaseous combustion model is described based on the analysis of chemical kinetics and eddy dissipation principle. In addition, the model utilises theoretical evidence that the mean production rate in proportional to the PDF of the mixture fraction at stoichiometic conditions. The combustion model is implemented within the SMARTFIRE fire field model. In the new model, a fast chemical reaction rate was assumed with the combustion reaction rate given by empirical equations similar to that of Brizuela and Bilger but with the ability to applied from lean to rich areas of combustion, overcoming a deficiency of the Brizuela and Bilger model. To demonstrate the combustion model, comparisons and analysis were made for the well known Steckler fire case and one of the LPC test fires. Other combustion models including eddy dissipation model and the modified eddy break-up model by Brizuela and Bilger were also used for comparison. It is demonstrated that the new model performed as good, or better than these other combustion models.
The simulation of ship evacuation under fire conditions
Galea E.R., Lawrence P, Gwynne S., Filippidis L.,
Blackshields D., Sharp G., Hurst N., Wang Z., and Ewer J.
Proc Fire and Safety at Sea, Rocarm Pty Ltd, Melbourne Australia 17-19 March
2004, day2, session 1, pp 1/14 -14/14, 2004.
Abstract
When designing a new passenger ship or modifying an existing design, how do we
ensure that the proposed design and crew emergency procedures are safe from an
evacuation resulting from fire or other incident? In the wake of major maritime
disasters such as the Scandinavian Star, Herald of Free Enterprise, Estonia and
in light of the growth in the numbers of high density, high-speed ferries and
large capacity cruise ships, issues concerning the evacuation of passengers and
crew at sea are receiving renewed interest. Fire and evacuation models with
features such as the ability to realistically simulate the spread of fire and
fire suppression systems and the human response to fire as well as the
capability to model human performance in heeled orientations linked to a virtual
reality environment that produces realistic visualisations of the modelled
scenarios are now available and can be used to aid the engineer in assessing
ship design and procedures. This paper describes the maritimeEXODUS ship
evacuation and the SMARTFIRE fire simulation model and provides an example
application demonstrating the use of the models in performing fire and
evacuation analysis for a large passenger ship partially based on the
requirements of MSC circular 1033. The fire simulations include the action of a
water mist system.
Safer by Design: Simulating Fire and Escape at sea
Galea E.R., Grandison A., Filippidis L., Gwynne S., Ewer J.
and Lawrence P
Proc 1st Int Conference Escape, Evacuation and Recovery, Survival from Ships and
Offshore Structures, Lloyds List Events, London 10-11 March 2004, session 3, pp
1-22, 2004.
Abstract
When designing a new passenger ship or modifying an existing design, how do we
ensure that the proposed design and crew emergency procedures are safe from an
evacuation resulting from fire or other incident? In the wake of major maritime
disasters such as the Scandinavian Star, Herald of Free Enterprise, Estonia and
in light of the growth in the numbers of high density, high-speed ferries and
large capacity cruise ships, issues concerning the evacuation of passengers and
crew at sea are receiving renewed interest. Fire and evacuation models with
features such as the ability to realistically simulate the spread of heat and
smoke and the human response to fire as well as the capability to model human
performance in heeled orientations linked to a virtual reality environment that
produces realistic visualisations of the modelled scenarios are now available
and can be used to aid the engineer in assessing ship design and procedures.
This paper describes the maritimeEXODUS ship evacuation and the SMARTFIRE fire
simulation model and provides an example application demonstrating the use of
the models in performing fire and evacuation analysis for a large passenger ship
partially based, but exceeding the requirements of MSC circular 1033.
Predicting the Performance of Passenger Ships using Computer Simulation
Galea E.R., Filippidis L., Gwynne S., Lawrence P.J. and
Blackshields D
Fire Safety Engineering Group
University of Greenwich
London SE10 9LS, UK
Abstract
When designing a new passenger ship or naval vessel or modifying an existing
design, how do we ensure that the proposed design is safe from an evacuation
point of view? In the wake of major maritime disasters such as the Herald of
Free Enterprise and the Estonia and in light of the growth in the numbers of
high density, high-speed ferries and large capacity cruise ships, issues
concerned with the evacuation of passengers and crew at sea are receiving
renewed interest. In the maritime industry, ship evacuation models are now
recognised by IMO through the publication of the Interim Guidelines for
Evacuation Analysis of New and Existing Passenger Ships including Ro-Ro. This
approach offers the promise to quickly and efficiently bring evacuation
considerations into the design phase, while the ship is "on the drawing board"
as well as reviewing and optimising the evacuation provision of the existing
fleet. Other applications of this technology include the optimisation of
operating procedures for civil and naval vessels such as determining the optimal
location of a feature such as a casino, organising major passenger movement
events such as boarding/disembarkation or restaurant/theatre changes,
determining lean manning requirements, location and number of damage control
parties, etc. This paper describes the development of the
maritimeEXODUS evacuation model which is fully compliant with IMO requirements
and briefly presents an example application to a large passenger ferry.
The airEXODUS Evacuation Model and its Application to Aircraft Safety
Galea E.R., Blake S.J., Lawrence P.J., and Gwynne S.
Fire Safety Engineering Group
University of Greenwich
London SE10 9LS, UK
Abstract
Computer based mathematical models describing the aircraft evacuation process
have a vital role to play in the design and development of safer aircraft, the
implementation of safer and more rigorous certification criteria, in cabin crew
training and post-mortem accident investigation. As the risk of personal injury
and the costs involved in performing full-scale certification trials are high,
the development and use of these evacuation modelling tools are essential.
Furthermore, evacuation models provide insight into the evacuation process that
is impossible to derive from a single certification trial. The airEXODUS
evacuation model has been under development since 1989 with support from the UK
CAA and the aviation industry. In addition to describing the capabilities of the
airEXODUS evacuation model, this paper describes the findings of a recent CAA
project aimed at investigating model accuracy in predicting past certification
trials. Furthermore, airEXODUS is used to examine issues related to the Blended
Wing Body (BWB) and Very Large Transport Aircraft (VLTA). These radical new
aircraft concepts pose considerable challenges to designers, operators and
certification authorities. BWB concepts involving one or two decks with
possibly four or more aisles offer even greater challenges. Can the largest
exits currently available cope with passenger flow arising from four or five
aisles? Do we need to consider new concepts in exit design? Should the main
aisles be made wider to accommodate more passengers? In this paper we
discuss various issues evacuation related issues associated VLTA and BWB
aircraft and demonstrate how computer based evacuation models can be used to
investigate these issues through examination of aisle/exit configurations for
BWB cabin layouts.
Passenger Behaviour in Emergency Situations
E R Galea
Introduction
I went to the end of my row of seats and waited to get into the aisle, … The next thing I saw was thick black smoke coming from the front of the aircraft, I was sure it was coming from the front … I got hold of my shirt and held it against my mouth to stop taking the smoke in, but I still took smoke in, it was burning my throat and I couldn’t breathe. I couldn’t get into the aisle, so I decided to go over the seats, the middle was flat and down so I climbed over them and made my way to the front right hand exit (Manchester, 1985, female, 18 years of age).
This graphic account from a survivor of the tragic Manchester Airport B737 fire of 1985 (King, 1988; Owen et al., 1998b) challenges a number of myths concerning survivability and human behaviour during aircraft emergency situations. The most commonly-held myth about aircraft emergencies is that they are non-survivable – if you are involved in an aircraft emergency you are as good as dead. This fatalistic view is often related to me by members of the travelling public, perplexed that these apparently non-survivable aircraft accidents involve opportunities to evacuate and hence to study.
The second most common myth, held by members of the travelling public and many aviation professionals – conditioned by the popular media – is that given an aircraft emergency situation, the most common behavioural response is for passenger to panic. In common parlance, the idea of panic has become synonymous with evacuation.
However, the picture that emerges from detailed research into aviation accidents is one not of hopelessness and panic, but one in which the passenger has a very good chance of surviving and in which the passenger behaves in a reasonable and thought-out manner and through this rational behaviour can help increase his or her chance of survival. In this chapter we will examine some of the findings of this research and develop a better understanding of the facts about human behaviour during aircraft emergencies.
An Analysis of Human Behaviour during Aircraft Evacuation Situations using the AASK V3.0 Database
E R Galea, K M Finney, A J P Dixon, A Siddiqui, D P Cooney
Fire Safety Enginnering Group
University of Greenwich, London, UK
Abstract
The Aircraft Accident Statistics and Knowledge (AASK) database is a repository of survivor accounts from aviation accidents. Its main purpose is to store observational and anecdotal data from the actual interviews of the occupants involved in aircraft accidents. The database has wide application to aviation safety analysis, being a source of factual data regarding the evacuation process. It is also key to the development of aircraft evacuation models such as airEXODUS, where insight into how people actually behave during evacuation from survivable aircraft crashes is required. This paper describes recent developments with the database leading to the development of AASK V3.0. These include significantly increasing the number of passenger accounts in the database, the introduction of cabin crew accounts, the introduction of fatality information, improved functionality through the seat plan viewer utility and improved ease of access to the database via the internet. In addition, the paper demonstrates the use of the database by investigating a number of important issues associated with aircraft evacuation. These include issues associated with social bonding and evacuation, the relationship between the number of crew and evacuation efficiency, frequency of exit/slide failures in accidents and exploring possible relationships between seating location and chances of survival. Finally, the passenger behavioural trends described in analysis undertaken with the earlier database are confirmed with the wider data set.
The Use of Evacuation Modelling Techniques in the Design of Very Large Transport Aircraft and Blended Wing Body Aircraft
E R Galea, S J ;Blake, S Gwynne, P J Lawrence
Fire Safety Engineering Group
The University of Greenwich, London, UK
Abstract
Very Large Transport Aircraft (VLTA) pose considerable challenges to designers, operators and certification authorities. Questions concerning seating arrangement, nature and design of recreational space, the number, design and location of internal staircases, the number of cabin crew required and the nature of the cabin crew emergency procedures are just some of the issues that need to be addressed. Other more radical concepts such as blended wing body (BWB) design, involving one or two decks with possibly four or more aisles offer even greater challenges. Can the largest exits currently available cope with passenger flow arising from four or five aisles? Do we need to consider new concepts in exit design? Should the main aisles be made wider to accommodate more passengers? In this paper we demonstrate how computer based evacuation models can be used to investigate these issues through examination of staircase evacuation procedures for VLTA and aisle/exit configuration for BWB cabin layouts.
Simulating Ship Evacuation under Fire Conditions
E R Galea, P Lawrence, S Gwynne, L Filippidis, D
Blackshields,
G Sharp, N Hurst, Z Wang, J Ewer
Abstract
When designing a new passenger ship or modifying an existing design, how do we ensure that the proposed design and emergency procedures are safe for an evacuation resulting from fire or other incident? In the wake of major maritime disasters, such as the Scandinavian Star, Herald of Free Enterprise, Estonia, and in light of the growth in the numbers of high density ferries and large cruise ships, issues concerning the evacuation of passengers and crew are receiving renewed interest. Fire and evacuation models with features such as the ability to realistically simulate the spread of heat and smoke and the human response to fire as well as the capability to model human performance in heeled orientations linked to a virtual reality environment that produces realistic visualisations of the modelled scenarios are now available and can be used to aid the engineer in assessing ship design and procedures. This paper describes the maritimeEXODUS ship evacuation and the SMARTFIRE fire simulation model and provides an example application demonstrating the use of the models in performing fire and evacuation analysis for a large passenger ship partially based, but exceeding the requirements of MSC circular 1033.
The Use of Evacuation Simulation, Fire Simulation and experimental Fire Data in Forensic Fire Analysis
H Jiang, S Gwynne, E R Galea, P Lawrence, F Jia, H Ingason
Abstract
This paper examines the application of evacuation and fire modelling tools to forensically analyse a fire scenario similar to the tragic Gothenburg fire incident of 1998. It is not claimed that the analysis accurately reproduces the Gothenburg incident, as a key component required for such a forensic analysis, i.e. the evolution of the fire, is not adequately represented within the evacuation model. However, the model predictions bare a striking resemblance to the events that took place during the actual incident. The model predictions correctly show that the evacuees experienced severe congestion during their attempted evacuation. While over predicting the number of fatalities, the model successfully predicted the fatality order of magnitude. Furthermore, the predicted location of the fatalities matched that found in the actual incident. In addition, the number of injuries predicted in this scenario matched those produced during the actual incident. The analysis provides insight into the tragic event and an understanding of why so many people died at the Gothenburg incident. Clearly, evacuation and fire simulation models have an important role to play in fire investigation.
Validating the buildingEXODUS Evacuation Model using Data from an Unannounced Trial Evacuation
J Parke, S Gwynne, E R GAlea, P J Lawrence
Abstract
In this paper data collected from an unannounced trial evacuation is briefly presented. This data is then used as part of a validation exercise for the buildingEXODUS evacuation model. In particular, the data is used to demonstrate the sensitivity of the model to the data provided and to verify the capabilities of the model in accurately representing these scenarios.
Simulating the Interaction of Pedestrians with Wayfinding Systems
L Filippidis, E R Galea, S Gwynne P J Lawrence
Abstract
In this paper, we introduce into circulation and evacuation models the concept of pedestrian interaction with wayfinding systems such as signage. The concept of signage Visibility Catchment Area introduced into the buildingEXODUS software is described and extended to include pedestrian signage interaction. This allows the simulated agents to take into account perceived visual cues provided by the signage system when making wayfinding decisions. These new features are examined to determine their effectiveness.
The Collection and Analysis of Pre-Evacuation Times Derived from Evacuation Trials and their Application to Evacuation Modelling
S. Gwynne, E R Galea, J Parke, J Hickson
Fire Safety Engineering Group
University of Greenwich, London SE10 9LS, UK
Abstract
This paper presents data relating to occupant pre-evacuation times from university and hospital outpatient facilities. Although the two occupancies are entirely different, they do employ relatively similar procedures: members of staff sweep areas to encourage individuals to evacuate. However, the manner in which the dependent population reacts to these procedures is quite different. In the hospital case, the patients only evacuated once a member of the nursing staff had instructed them to do so, while in the university evacuation, the students were less dependent upon the actions of the staff, with over 50% of them evacuating with no prior prompting. In addition, the student pre-evacuation time was found to be dependent on their level of engagement in various activities.
Key words: data, evacuation, pre-evacuation, hospital premises, university premises.
Analysing the Evacuation Procedures Employed on a Thames Passenger Boat using the maritimeEXODUS Evacuation Model
S Gwynne, E R Galea, C Lyster*, I Glen*
Fire Safety Engineering Group, University of Greenwich,
30 Park Row, London SE10 9LS. UK
*Fleet Technology, Canada
Abstract
On the 19 June 2001, a Thames passenger/tour boat underwent several evacuation trials. This work was conducted in order to collect data for the validation of marine-based computer models. The trials involved 111 participants who were distributed throughout the vessel. The boat had two decks and two points of exit from the lower deck placed on either side of the craft, forward and aft. The boat had a twin set of staircases towards the rear of the craft, just forward of the rear exits. maritimeEXODUS was used to simulate the full scale evacuation trials conducted. The simulation times generated were compared against the original results and categorised according to the exit point availability. The predictions closely approximate the original results, differing by an average of 6.6% across the comparisons, with numerous qualitative similarities between the predictions and experimental results. The maritimeEXODUS evacuation model was then used to examine the evacuation procedure currently employed on the vessel. This was found to have potential to produce long evacuation times. maritimeEXODUS was used to suggest modifications to the mustering procedures. These theoretical results suggest that it is possible to significantly reduce evacuation times.
Key words: maritimeEXODUS, evacuation model, validation, ship, simulation.