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Wednesday 21 December 2016

Conditions for risk based ship survivability approach: a study on the analysis of fire risk


Published article:Liwång, H. (2016). Conditions for risk based ship survivability approach: a study on the analysis of fire risk. Naval Engineers Journal, 128(3), 31-45.
Some comments from the article
The purpose for introducing a risk-based approach is to identify risks in the intended operation of the ship and use this information to guide the concept development and ship design using a risk-based ship design approach. The uncertainty in the design decision making is generally high when novel concepts are developed. Therefore, a rational ship design support process is necessary to avoid erroneous assumptions that affect design choices. Risk analysis is a knowledge model that may reduce this uncertainty. Based on this need, the proposed analysis models are in this paper used to identify critical aspects and gaps in the analysis process, specifically for naval ships.
Risk controls must be analyzed with respect to susceptibility, vulnerability and recoverability; the total effect of these aspects must be understood to evaluate survivability. The fire risk cannot be analyzed without a general analysis of a ship’s susceptibility and vulnerability with respect to relevant threats, which indicates that the analysis depends on relevant multiple operational scenarios.
Physical descriptions of fire depend on the ship specifications, and for the same operational scenario, the ship design concept will vary due to differences in the ship tactics, susceptibility and vulnerability. The example in this paper demonstrates that the ignition frequency for weapon-ignited fires depends on the location of the compartment; this is not the case for accidental fires. Different design concepts will also require different passive and active fire protection depending on the differences in the design and how it is manned. For example, if an FRP concept is considered, the combustible nature of FRPs can contribute to the fire in extreme fires; in other cases, with higher expected frequencies, the thermal insulation of FRP will yield a smaller fire zone and contribute to survivability.
The critical systems must be identified to analyze the ship kill levels. These critical components and systems depend on the ship design and assumed tasks after a hit (often described as the ship survivability levels). Typical critical systems include the propulsion system and power supply.
The importance of firefighting on naval ships is highlighted in the study which show that firefighting is the most important aspect for reducing the probability of catastrophic consequences from complicated ignition cases because the built-in protection is insufficient for stopping the fire escalation. The reaction times and effectiveness with respect to firefighting onboard naval vessels are difficult to compare with other firefighting conditions thanks to extensive training, a high level of readiness, high number of crew members relative to the ship size and good firefighting equipment availability.
Certain problems have been raised for risk-based approaches, especially for defining the scenario, such as limited research and perceptions. However, these problems are consistent among most analysis approaches, but heavy use of complicated tools may hide these aspects and make validation more complicated. Further, uncertainties are particularly challenging, especially for analyzing antagonistic threats. On the other hand, a probabilistic approach offers a framework that is consistent from theory to the first principle tools, which has been found to improve the decision-making process when selecting among candidate survivability design principles.
You can find a free full text version here.

Tuesday 6 December 2016

Article examining reported piracy incidents off West Africa

(C) H. Liwång 2016
I’ve heard a lot of stories about the piracy attacks off West Africa. I therefore had to examine the reported incidents to see what was true or could be identified by the official reports. The resulting journal article is now published. It is clear from the study that piracy off West Africa is violent and pose a substantial threat to shipping in the Region.

Abstract:
Piracy is one of the most frequent maritime threats. However, despite the importance of how maritime piracy is to be reduced, it is substantially less investigated than maritime safety. Piracy off Somalia is the most investigated case of piracy, but those results are not necessarily generalizable. Piracy off West Africa has been shown to be more diverse, successful and dangerous.
This study investigates and analyses piracy off West Africa with the aim to understand how different operations and security measures affect the consequences of piracy.
This study has identified several different intents and shows that most attacks are relatively close to shore and correspond to areas of high ship density. Attacks with the intent of theft at night-time are generally performed close to shore, and more complicated attacks against ships under way are more common during daytime and farther from shore. Five types of measures are found to have high effectiveness if the attack is detected during approach; after boarding, only two measures have high effectiveness. Of the effective measures, it can be concluded that all but one are dependent on detecting the attack. Therefore, detecting the pirates is key but must be accompanied by a set of measures because no measure alone can protect a ship given the operational conditions off West Africa. The risks associated with piracy off West Africa are estimated to be of the same magnitude as the risks posed by Somali piracy at its peak.

The article describes the risk levels with an event tree. (C) Liwång 2016.

Wednesday 16 November 2016

Am I orthogonal to the market?

Nicolas Negroponte (MIT Professor) just told me and others at a MIT event that research should be orthogonal to the market, i.e., we should try to do the things the market cannot do. I think his advice make sense.

I don't know if I am orthogonal. I must identify my angle to the market and articulate it. However, the same is true for some research funding organizations.

Thursday 3 November 2016

The risk-based method for assessing environmental risks from wrecks


Chalmers University of Technology has in cooperation with the Swedish Maritime Administration developed a risk analysis method/tool for assessing environmental risks from wrecks, VRAKA. This is one of the research focuses within the Swedish work with wrecks that I write about in my last post (here).
Challenging aspects of this risk assessment model is must probably the uncertainties, but also the fact that it must cover a complicated combination of environmental consequences from oil to explosives and chemical weapons. These have both short term and long term effects that need different considerations in general and dependent on the specific conditions for every wreck. This generally is a demanding task for any risk assessment approach.


But don’t take my word for it, read a PhD thesis on the topic by one of the persons that have been working with the approach… (Environmental risk assessment of shipwrecks – Model development and application by Hanna Landquist)


Hanna Landquist is a PhD-student at Chalmers until Novenber 11 (2016) when her dissertation is planned to be held.

Saturday 29 October 2016

Toxic risk from sunken ships off the Swedish coast


Both media and research focus has been put on the risk posed by sunken ships off the Swedish coast. One especially media friendly collection of wrecks are the wrecks on the Swedish Exclusive Economic Zone (EEZ) off the island and lighthouse Måseskär (west of Orust on the Swedish west coast). After World War II German ships were sunk there by the allies, the ships were filled with German ammunition and chemical weapons. The number of ships, the amount of ammunition, what type of chemical weapons and so on is unclear. After reading reports from the latest investigations on site (Swedish Maritime Administration, 2015) it is clear that it is bad. However, the claims made over the last 20-30 years by journalists about the number of ships and amount of mustard gas is most probably exaggerated and a result of unreliable secondary sources. But let us not focus on those issues because the problems are real no matter what.
The work localizing and learning more about the wrecks off Sweden is an intriguing  mix of diving, ROVs, archive searches, risk analysis and classic detective work. It thus includes an important, challenging and close cooperation between researchers and practitioners. It is from 2016 decided that the (new) agency Swedish Agency for Marine and Water Management (SwAM or HaV in Swedish) is responsible for the coordination of the work and late 2016 the first wrecks will be investigated for oil and emptied if oil is found. The first wreck to be drilled for oil is the Thetis in the Skagerrak. The SwAM is also aiming for IMO to ban fishing around the ammunition  ships off Måseskär on the Swedish EEZ.
The list of the most prioritized wrecks (the emergency to-do list) also include ships in other positions than off the Swedish west coast. One is just of my home island where I and many others often passes over it on the fairway to and from Stockholm. It is the cargo ship Harburg, she collided February 16, 1957 with the tanker Tinny. Harburg sank fast and 10 men were killed. Tinny of 16450 DWT, loaded with gasoline, was on her way to Stockholm and hit Harburg amidships and probably caused the boiler to explode and tare the ship up from inside. The collision pushed Harburg down under Tinnys keel. Harburg sits on approximately 30-37 m depth about 180 meters from shore. The ship is broken just in front of the first cargo hold with the bow lying flat on the ground and the aft part of the angle from the bottom. Harburg has previously leaked oil.

An interesting side story to this investigation is that neither fishermen nor fish are stupid ;-)

While on site the Swedish Maritime Administration used both side scan sonars and ROVs to investigate the wrecks. What was evident from the sonar data was that the waters are often used as fishing ground for bottom trawling. From the tracks it is clear that the fishermen knows the positions of all the wrecks and to a good job dragging the trawl in-between as shown on the picture below.
Tracks from bottom trawling. (C) the Swedish Maritime Administration, 2015.
However, also the fish seems to have grasped the important aspects of the situation and spend their time cramped together just around the wrecks. This is evident from the ROV reports as there was problems getting any shots of the wrecks and cargo onboard as a result of all the fish. (Sadly the Swedish Maritime Administration does not publish the pictures with the fish, the focus on the wreck. However, you can find fish also on those pictures as shown below.) I suspect that the fish has analyzed the fishermen's activity and now make sure to spend their time where they are out of reach for the trawlers...
ROV and side scan sonar pictures. Note the weapons on the ROV pictures and around the ships on the sonar picture, but also the fish on the top left picture. (C) the Swedish Maritime Administration, 2015.
Reference
Swedish Maritime Administration, 2015. Miljörisker sjunkna vrak II, Undersökningsmetoder och miljöaspekter [Environmental risks from sunken wrecks II, Investigation and environmental aspects]. Dnr: 1399-14-01942-15. Swedish Maritime Administration

Thursday 11 August 2016

Who owns a problem definition?

It’s no secret that I’m inspired by operation analysis when it comes to my scientific views. Operations analysis evolved as a problem oriented science with the focus to support decision makers when facing complex problems. Such problems depends on how they are defined and for example on where you put you system boundaries.
In the book ‘System – Att tänka över samhälle och teknik’ (English translation: ‘Systems – To think about societies and technology’) Professor Lars Ingelstam describes the idea of systems and system sciences. He also talks about operational analysis and what Ingelstam calls the democracy-analytical dilemma:

Whit what right does a researcher or analyst question how a politician elected by the people define their problems?
As Ingelstam states it is of course an analyst's role to also work with the problem definition. A decision maker can, despite good intentions, have defined a vague problem or misjudged assumptions or misunderstood the underlying causal relationships. But, as Ingelstam caustions, the challenge does not stop there. Who is to stop the analyst from trying to fit the problem to his or her favorite tool or own interest (maybe as a result of a too inbreeded academic environment).

Therefore, we system analyst cannot take problem definitions for granted, but should also encourage decision makers to challenge our analysis and it is in that dialog we can get closer to the ‘truth’. Today’s problems are complex in my field, and in most other fields as well, but as Mike C Jackson writes “we have no right to be pessimistic … given the suffering that results from these problems”.
Ingelstam, L. (2012). System, Att tänka över samhälle och teknik [Systems – To think about societies and technology]. Eskilstuna, the Swedish Energy Agency.

Monday 4 July 2016

Influences on threat assessment in a military context



I've had the pleasure of assisting a colleague in writing an article now published in Defense and Security Analysis (ISSN 1475-1798, E-ISSN 1475-1801):

Abstract
The anchoring effect is a well-studied subject. This article connects the effect with the rules-in-use within a military intelligence institution. Particularly the rules-in-use that dictate that an analyst takes his or hers starting point from recently conducted assessments of the specific area or threat. The threat assessment as well as the written assessment were affected. The results show that officers have an aversion to lower a previous given threat assessment. This gives that to understand risk assessment we not only need to understand the methods used, we also need to understand the institutions in which they are used. This is especially relevant for military intelligence as the assessments are conducted in an environment of high uncertainty.

Authors: Martin Bang and Hans Liwång
Department of Military Studies, Swedish Defence University, 11593, Stockholm, Sweden.

Thursday 28 April 2016

Boaty McBoatface, why not?


I’m into research and I like boats, both serious boats  for research and boats for recreational use even if they sometimes aren’t serious. I don’t like boats with stuck up names!
English is not my native language and most names sounds more promising if they are originate from another language, but I know there are many names much worse than Boaty McBoatface. I also hope to think that the ship and it's tasks are bigger than the name of the ship, any name.

Sunday 24 April 2016

I wish Draken Harald Hårfagre fair winds!

Updated April 26 2016:

The world´s largest viking ship Draken Harald Hårfagre has now left Haugesund, Norway and sails towards Canada and USA via Iceland, Greenland. They will cross the North Atlantic Ocean, to explore the world as the Vikings did a thousand years ago. On their webpage (see link above) you can follow the ship's progress.

The 33-person strong crew will most likely have a exciting (and challenging) voyage with the harsh conditions upon them all the time and with only a tent as protection when sleeping. I'm not a history buff, but this project I like!


Bon voyage and fair winds!

Friday 15 April 2016

Maritime security: information has gone missing?


I’ve followed maritime security with a systematic approach since 2010. In my research, and when discussing maritime security measures with ship operators, reliable and systematic descriptions of incidents are important. Without such information also I’m left with nothing but guesswork. I’ve over the years come across information or descriptions of incidents that doesn’t appear in the statistics or correspond with the general beliefs.

Case 1. The first discrepancy is that one about the effectiveness of armed guards on ships which is by many claimed to be 100% effective off Somalia. I’ve heard many say “a ship with armed guards have never been successfully attacked by pirates (off Somalia)”. This is off course not a true statement:

Firstly: at sea (and in many other situations) nothing is 100% except the fact that you don’t have all the information.

Secondly: I’ve heard a couple of very reliable accounts about incidents off Somalia from different years, situations and ships describing successful boarding’s on ships with armed guards. A typical end to such an incident is that the armed guards throw their weapons over board when they realize they are beaten and the company providing the guards takes responsibility over (not) reporting the incident.

Thirdly: The people typically making claims about armed guards being the only 100% effective measure (ship operator executives) should be smart enough to know that the claim isn’t true.

Fourth: In other areas, such as off Nigeria, even the official effectiveness of armed guards is far from 100%.

I don’t know the correct figure for the effectiveness of armed guards off Somalia (it is however high) and I’ve not tried to investigate it either. My point is that the case of armed guards is an example of how poorly the truth sometimes is treated when reporting maritime security incidents.

Case 2. For a coming publication I searched for records of incidents off West Africa 2012 and 2013 that wasn’t included in the official ICC International Maritime Bureau (IMB [https://icc-ccs.org/]) statistics. I found some records illustrating that incidents without consequences, i.e., such as a suspicious approach without boarding, not always was reported. This is not surprising, for many seafarers this as seen as a normal, but unpleasant, day in that area. I.e., nothing to report.

More surprising was the high profile incidents I found where the paper trail was disappearing fast. With high profile I here mean European or North American ship operators in combination with severe consequences such as kidnapping. For a couple of such incidents (I found four) no records at all were included in the IMB incidents description even though there were newspaper articles describing at least some aspects of the incidents.
I understand that reporting such incidents isn’t your first priority or sometimes not even possible during an attack. But it should be in the industry’s interest that at least some basic aspects such as date, time, position, and consequence in general terms are reported in the days or weeks after. This to make sure that the situation at sea can be captured, communicated and reacted on as correctly as possible. Especially given the sea blindness shore based decision-makers seem have.

It takes (at least) two to tango


I, as many else, have noticed the US information about the interactions between the USS Donald Cook and two Russian SU-24 airplanes on internarial water in the Baltic Sea. According to the New YorkTimes who bases their information on White House sources the planes “violated professional military norms over the Baltic Sea when one of its planes flew ‘dangerously close’ to an American ship and a Polish aircraft”.

Based on the video footage it’s clear that the basic information is true, but how to define “professional military norms” and “dangerously close” is off course debatable and is as much up to culture as anything. I’m convinced that the definition of these concepts differ between US and Russia and most probably also within US such as between an US navy pilot and a politician in the White House.
The Baltic Sea a more quite day. Photo © Hans Liwång.
The flight has also by Congressman Adam Kinzinger been described as a practice attack. Based on my knowledge it does not look like an attack, it looks like a message being communicated as well as a photo opportunity. The message being communicated by the Russian planes to me looks very much the same as the message most military forces is communicating in general and more specifically by USS Donald Cook by being in the Baltic Sea.

There is a DANGEROUS dance being performed in the Baltic Sea with more than two dancers.

Thursday 18 February 2016

When do we know if something is a problem?

I’ve written about this before, both when discussing the implications of an unidentified submarine in the Stockholm waters (described in Should we in Sweden be surprised when we learn that there are foreign submarines in the Stockholm archipelago? Hardly!) and when I try to decide if my bike route to work is dangerous or not (two posts: (i) Risky business on land and (ii) One accident doesn’t mean thing is risky).

Now, a couple of days ago I witnessed the result of one more bike accident at the very spot described before. This time I estimate that the accident was a result of the sharp turns in combination with the curb stones collecting water that had frozen during the night, i.e., the physical layout created a hazardous condition.

So, the question is: I have a record of a very low number of incidents (in the submarine case one incident, and in the bike lane case two incidents), can I judge (calculate) the likelihood of this being evidence of a problem?

Note: In these cases I have a record of the incidents and the number of incidents and conditions for each incident are known. I don’t base it on hearsay or for example on newspaper articles talking about many biking accidents (which could be ten persons describing what could be the same accident). For the submarine incident this means that I trust the description the Swedish Armed Forces gave regarding some basic aspect of the incidents.

Judging if the incidents are a one-time event or evidence of a bigger problem came in the submarine case down to estimating how likely it is that we observe a submarine if it is in the area. In the biking case observing is not a problem, i.e., it is about how often we are on the scene.

For being able to calculate total number of bike accidents we need more information. In short we need to estimate how often I’m on site and what that mean.
Calculation example: Rush-hour accidents (in one intersection)
No of observed incidents: 2

Observation time per day [minutes]: 1
Observations per week [per week]: 9
Average incident observation window [min] (duration of accident): 10


Total period [years]: 1.5
Weeks per year [weeks]: 46
Days per week [days]: 5
Hours per day, rush-hour [hours]: 2


=> Total period [minutes]: 41400
=> Total observation time [minutes]: 6831
=> Observation percentage: 17%

Estimated no of incidents in total (from observation percentage): 12

Bikers per minute (during rush-hour): 2
=> Sample size, calculated [no of bikers]: 13662
=> Incident per observed biker: 0.01%

Statistical error margin (given sample size and a 95% confidence and normal distribution): 0.02%
=> Number of incidents: 0.01% ±0.02%, i.e., between -5* and 29

*) we cannot have negative number of accidents, i.e., assumption about normal is distribution wrong (wrong left tail). Two incidents are observed, i.e., these two could statistically be the only two

=>                                                   
Minimum number of incidents (the observed ones): 2
Expected number of incidents: 12
Maximum number of incidents (given stat. error margin): 29

Per year
Minimum number of incidents: 1
Expected number of incidents: 8
Maximum number of incidents: 19

But if this 1 to 18 accidents per year in one intersection a problem? Is it too often? If we put that question in a safety (risk) perspective we also need to know the consequence of an incident. I estimate that one out 20 incidents lead to serious injuries. The probability for exactly N injuries is then described by the binomial distribution. Given this frequency, the expected number of incidents and the binomial distribution we can calculate the probability for exactly one, two, three… serious accidents per year. Then we can calculate a FN-curve for each of the three number incidents above (1, 8 and 19 per year) where N is the number of persons seriously injured per year in this intersection.

FN-curve describing the probability for N or more serious injured persons per year if there is one accident per year (filled circle); eight accidents per year (circle); and 19 accidents per year (squares). (C) Hans Liwång 2016.
However, to my knowledge there are no FN-criteria for one intersection, so we still do not know if this is a problem or not. I however note that the probability for at least one seriously injured person per year is close to one which sounds high for one insignificant intersection (I pass at least 40 of that size per day).

The most crucial figure in the calculation above is the average duration of an incident. Note also that if my wife, who also twice a day pass the same spot on her bike, tell me that she had an accident on this spot I could not include that information because it is outside my sample.

I promise to get back with a maritime case complementing the FN-curve I did when describing that the risk for refugees in the Mediterranean so high it is intolerable.