Scholarly article on topic 'Natural world contradiction matrix: How biological systems resolve trade-offs and compromises'

Natural world contradiction matrix: How biological systems resolve trade-offs and compromises Academic research paper on "Psychology"

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Procedia Engineering
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{Discontinuous / Evolution / Conflict / Breakthrough / Nature}

Abstract of research paper on Psychology, author of scientific article — Darrell Mann

Abstract The paper describes updates to the TRIZ Contradiction Matrix tool. The tool has been constructed following an extensive programme of research to uncover and codify the strategies used by biological systems to overcome conflicts, trade-offs and compromises. The paper is divided into three main sections. In the first section, we discuss the dynamics of contradiction emergence and resolution in nature. The aim in this section is to define a set of heuristics to help determine when and where nature is likely to experience and therefore have to resolve contradictions. The second section of the paper goes on to present a number of examples of conflict resolution in nature. The third and final section of the paper then moves on to examine the main similarities and differences between the strategies used by nature to resolve trade-offs and compromises and those used by human designers. The basis of this comparison is the Matrix 2003 tool developed from our parallel studies into trade-off resolution in human engineered technical systems.

Academic research paper on topic "Natural world contradiction matrix: How biological systems resolve trade-offs and compromises"

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Procedía Engineering 9 (2011) 714-723

TRIZ Future Conference 2006

Natural world contradiction matrix: How biological systems resolve

trade-offs and compromises

Darrell Mann *

Director, Systematic Innovation Ltd, UK


The paper describes updates to the TRIZ Contradiction Matrix tool. The tool has been constructed following an extensive programme of research to uncover and codify the strategies used by biological systems to overcome conflicts, trade-offs and compromises. The paper is divided into three main sections. In the first section, we discuss the dynamics of contradiction emergence and resolution in nature. The aim in this section is to define a set of heuristics to help determine when and where nature is likely to experience and therefore have to resolve contradictions. The second section of the paper goes on to present a number of examples of conflict resolution in nature. The third and final section of the paper then moves on to examine the main similarities and differences between the strategies used by nature to resolve trade-offs and compromises and those used by human designers. The basis of this comparison is the Matrix 2003 tool developed from our parallel studies into trade-off resolution in human engineered technical systems.

© 2011 Published by Elsevier Ltd.

Keywords: Discontinuous; Evolution; Conflict; Breakthrough; Nature;

1. Introduction - Nature the great optimizer

60 years of TRIZ research has clearly demonstrated the importance of contradiction emergence and resolution as the primary driving force of evolutionary advance in man-made systems. Comparable studies of evolutionary advance in nature, although rarely using the term 'contradiction', highlight a remarkably consistent message (Reference 1, 2). As with human engineered systems operating in a competitive environment, the primary driving forces in nature revolve around 'survival of the fittest'. As often told in the clichéd joke involving two men being chased by a tiger, the problem is not about whether humans can run faster than tigers, but whether one human can run faster than another. In other words, we only have to be slightly better than our immediate competitors in order to be the one to survive to live another day. Ultimately, of course, someone invents a shotgun to shoot the tiger, thus solving a contradiction and forever changing the game in favour of the human. At this point in time, the tiger has not been successful in countering the bullet threat. The point of mentioning this story is that the invention of a game-

* Corresponding author.

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1877-7058 © 2011 Published by Elsevier Ltd. doi:10.1016/j.proeng.2011.03.160

changing strategy tends not to happen that often. Far more normal in nature is that the overall eco-system sets up natural balances that will cause a given sub-system to 'optimize' itself at a given level. In the case of the tiger-versus-human story, if humans were the only prey of tigers and the tigers got really good at killing humans then the number of tigers would grow while the number of humans would shrink. Ultimately then the number of humans would be insufficient to feed all the tigers and so some parts of the tiger population would starve and the number of tigers would 'naturally' drop. These balances are everywhere in nature. Nature is a great optimizer. Nature represents the ultimate 'self-correcting' system. Figure 1, for example, presents a reproduction of the classical population dynamics study in nature - the lynx versus hare (Reference 3).

Amazing though such self-correcting systems are, they have little to teach us when we are looking for examples of 'breaking' contradictions. This oscillating boom-and-bust population cycle is the 'natural order'. In the research to identify how and where nature solves contradictions, these cycles have little to tell us. What we are looking for are the moments when the game is changed. We are looking for the natural world's equivalent of inventing the shotgun. More specifically, we are looking for situations where a natural system makes a discontinuous shift from one way of doing things to another.

1.1. When nature changes the game

Not quite a hare, but a good example of the sort of thing we are looking for is the Skomer rabbit. In most peoples' minds the rabbit's most famous characteristic is its ability to create other rabbits. Largely driven by a Figure 1 like cycle, the 'normal' rabbit response to the predation threat is very simply to keep on producing as many new rabbits as possible - with typically up to 8 breeding cycles per year, and each cycle potentially producing 10 offspring. This population growth can only happen for so long however since sooner or later the amount of food available to feed the rabbits becomes insufficient to sustain the population. The rabbit population thus goes through its own cyclic periods of boom and bust. On Skomer, a small island off the coast of Wales, however, the rabbit population does not exhibit this boom-bust oscillation. The rabbits on Skomer will typically breed only once a year and each pair will typically only raise three offspring per year (Reference 4).

When we see an evolution jump away from the 'norm' like this, we can be reasonably certain that nature has successfully found a way of solving a contradiction. The contradiction in the case of the Skomer rabbit is a desire to avoid the 'waste' of boom-bust cycles, which is traditionally prevented by an inability to predict how much food (or how many predators) will be around in the future. The 'discontinuous jump' solution to this problem now present in the Skomer rabbit population is the identification and incorporation of a feedback loop. The urge to breed in the Skomer rabbit population has been linked to population density. In other words, if a Skomer rabbit looks around and sees lots of other Skomer rabbits, the 'breed now' signal somehow gets switched off.

From a biological stand-point, this description is somewhat over-simplified of course. But it does offer us the essence of the research task at hand when we are attempting to codify what nature does when faced with contradictions. What has happened here with the Skomer rabbit case is what we have to do with all of the other

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Figure 1: 'Self-Correcting' lynx-versus-Hare population dynamics

discontinuous jumps we find: firstly we work out what the core contradiction is, and then we reverse engineer how it has been solved. In this case, then, the entry into our knowledge database would show this problem as a waste ('loss of substance') versus inability to predict future food/predation ('amount of information' and/or 'ability to detect') conflict, the resolution to which involved the addition of a new feedback loop, Principle 23.

1.2. When the game changes on nature

Sometimes the contradiction nature has to solve emerges due to a shift in the external environment. Another classic evolutionary biology case study highlighting this effect is the Peppered moth (Figure 2):

The basic story of the Peppered moth is straightforward (Reference 5): "The typical form of this species has whitish wings, speckled with black. In 1848, a black form, named carbonaria, was recorded in Manchester. The carbonaria form increased in frequency rapidly, so that by 1895, 98% of Mancunian Peppered moths were black. The melanic form spread to many other parts of Britain. By examination of old collections, Steward mapped the spread of carbonaria, concluding that all British carbonaria probably derived from a single mutation."

The explanation for the rapid transition from white to black moths in Manchester was very simply the Industrial Revolution. A habitat of the Peppered moth that was traditionally pale in colour 'suddenly' became covered in layers of soot. Pale coloured moths that would normally have been camouflaged thus became increasingly visible to predators. Dark-coloured moths therefore came to have a distinct evolutionary advantage and hence their population grew. The basic contradiction here is one between the desire to hide from predators and the fact that the environment changed. Not surprisingly, the Inventive Principle required to solve the contradiction in such a case was number 32, 'Colour Change'.

1.3. When the environment changes too quickly...

As we shall see later, the colour change 'strategy' - or mutation - is one that is relatively easy for natural systems to deploy. This plus the fact that moth populations tend to be quite large in terms of numbers means that there was sufficient time for the Peppered moth to respond to the changing environment. In other situations, however, nature is not so lucky. Particularly since mankind has added 'technology' to the evolutionary toolkit. Another classic evolutionary biology case study relevant here is the Dodo shown in Figure 3.

Figure 2: Pair of peppered moths - One carbonaria one white

Figure 3: The now extinct dodo

The Dodo used to inhabit the island of Mauritius in the Indian Ocean. Mauritius has a jungle-like habitat and so the dodo tended to feed by scrubbing around the roots of trees. The need to fly wasn't great and so, over time, the bird re-deployed its resources from wings to thighs and as a consequence became flightless. The Dodo also had no natural enemies and so evolved no natural defenses. When explorers came, they changed the system. Hunting a flightless, lazy, oblivious-to-danger Dodo was simple, and because they tasted pretty good too, it didn't take long before the explorers wiped out the whole population. There was no time for the bird to evolve a solution to the human explorer problem and consequently the contradiction was never solved. Now that man is changing the world seemingly ever more rapidly, we appear to be seeing large numbers of other species becoming extinct before they could solve the contradiction of their changing environment.

1.4. Evolution at biological speed...

Take mankind and technology out of the equation and we start to find somewhat larger numbers of biological examples of successful contradiction solving. The most obvious ones involve so-called evolutionary arms-races. These occur sporadically throughout evolutionary time, and usually involve a changing game between predator and prey. What we are looking for when we see these arm races are the strategies that either predator or prey use to shift the natural balance that previously existed. The Bombardier beetle (Reference 6) is a wonderful example of a whole progression of evolutionary jumps that have now created a formidable poison-throwing solution to the prey killing task of the beetle.

Evolutionary arms races shift the ecological balance from one stable position to another. As in the tiger versus two men example, the system will tend to re-stabilise at a new balance point rather than cause extinction. Basically when we are looking for contradictions we are thus looking for situations where we see this kind of discontinuous shift.

Arms races aren't the only contradiction-finding opportunity however. Arms races tend to take place over many generations of a life-form. We can find many cases of solved contradictions when we zoom-in to look at the fine details of changing environments. A good place to look is at a transition of one life stage to another. When a crab is safe inside its shell it has found a good solution to its predation problem. Crab-in-shell is what we might think of as the 'normal' environment. But shells don't tend to grow, while crabs do. Sooner or later during its growth cycle, the crab needs to solve this contradiction. It either needs to find a way of making a hard exo-skeleton grow or it needs to find a way to make the transition from one shell to another as safely and rapidly as possible.

Marine crabs tend to solve the contradiction by employing already existing appropriately shaped structures (the Hermit crab for example) or creating a temporary exoskeleton by pumping their outer layers full of seawater. A land crab on the other hand cannot use either of these strategies. A newly moulted black-back land crab (Gecarcinus lateralis) (Figure 4), on the other hand, has found a solution to the contradiction (Reference 7). It traps air within its gut and squeezes, firming up its entire body. Besides being the first known example of a gas-powered skeleton, the innovation may have been a key step in the evolution of land-based crustaceans.

Figure 4: Blackback land crab uses principle 29 to solve its moulting contradiction

1.5. Summary of factors driving discontinuous evolution

All in all then, nature tends to opt for optimization over discontinuous breakthrough change. Put more simply, nature has not found ways of solving large numbers of contradictions. Technology, for example, allows mankind to transport 400 tonnes of Boeing 747 across the ocean, whereas nature still hasn't found a way of lifting more than 22kg off the ground.

Nature, nevertheless, does make discontinuous jumps. Our job in this research is to find them and to then reverse engineer them. Unlike the world of technology and the fiercely competitive and highly transient commercial environment, the discontinuity rate in nature is relatively low. The most fruitful areas to look for nature solving contradictions we have found are (in no particular order):

• evolutionary arms races

• nature responding to a dramatic shift in local environment

• nature in transition from one steady state to another (birth, growth, mating, giving-birth, attack, defence)

• nature at the micro and nano scale

This latter topic is driven largely by evolution in bacteria. Evolution rates in this phyla can be tremendously high due to the ability to rapidly 'share genes' between different bacteria. This is an important area both in terms of man's never ending race to find cures for ever-evolving disease, but also because nature is currently a far more practiced nano-engineer than even the best of mankind's capability.

2. A few mini case studies

Every month we publish one of the biological case studies emerging from our research programme (Reference 8). The aim is to put together a more comprehensive and more scientifically valid version of the primary Russian TRIZ resource on biological systems (Reference 9). Here are a few random examples not appearing in that source. Let's start with an 'arms-race' example:

2.1. Jellyfish - are generally thought to be soft and squishy creatures. So how does what appears to be little more than a fluid filled bag attack prey that might happen to live inside a tough shell? They must shoot their stinging cells at crustaceans with enough power to puncture the animals' shells. Normal high speed cameras aren't fast enough to catch the strike, so researchers used an ultra-high speed camera, which captures 1.4 million frames per second (Reference 10). The results reveal that the stinging cells discharge in 700 nanoseconds, reach an acceleration of 5.4 million g, and strike with the force of some bullets. The lightning assault - which scientists currently believe is driven by a release of energy from stored collagen in the stinging cells' walls - is one of the fastest movements in the animal kingdom. Here we see a conflict operating on two different levels. At the highest level it is all about how a soft thing pierces a hard thing. At the more detailed level it is all about how the jellyfish manages to create the enormously high acceleration rate needed to solve the higher level problem.

The high-level problem can be viewed as a 'Force' (required to pierce the shell of the prey) versus 'Other Harmful Factors Acting On System' (i.e. the hard shell will damage the soft jellyfish) conflict. The strategy deployed by the jellyfish can then be viewed as an example of Principle 21, 'Hurrying' in action - i.e. perform the action quickly enough and the skin will be pierced.

At the more detailed level, the conflict is about the desire to achieve a high enough acceleration ('Force') with the lowest amount of energy and the simplest possible system. At this level, the Reference reveals the solution to involve the prior storing of energy in the collagen, (Principle 10).

2.2. Collared Lizard - when male collared lizards (Crotaphytus collaris) - Figure 5 - square off, they make sure their rival knows what they're packing. And it's not just teeth on display. Each opens his jaws wide enough to reveal his chomping machinery: Jaw muscles that reflect ultraviolet light hint at just how hard the lizard can bite.

This dramatic display of 'weapon quality', reported in Reference 11, is a classic 'look fierce without wishing to commit the resources to actually be fierce' contradiction. In more formal TRIZ terms it represents a conflict between Security and the Amount Of Energy required to achieve the desired effect. In taking advantage of UV and reflection, the collared lizard has made a discontinuous jump that can be mapped to applications of Principle 32 (Colour Change - which includes specific mention of UV) and 13 ('The Other Way Around').

Figure 5: Collared lizard

2.3. Philoponella vicina - while venom is the weapon of choice for most spiders, the creation and storage of such noxious substances comes with a relatively high resource cost. Philoponella vicina avoids this problem by utilising an alternative existing arachnid resource - web silk. This spider (Figure 6) wraps its prey in meters of silk to make a shroud. As the silk dries it shrinks slightly delivering a crushing force many times the spider's own weight, and enough to break legs and collapse compound eyes (Reference 12). The study is the first to show that wrapping can damage or even kill prey, instead of merely immobilizing it. Lacking poison to finish the job, Philoponella then regurgitates another existing resource - its digestive fluid - into the shroud, thus creating a self-contained liquid meal.

Figure 6: Philoponella vicina

As with the jellyfish story, the Philoponella vicina contradiction story works on two levels. The basic level contradiction is how to kill prey when the spider doesn't have a poison resource; the more detailed level problem is then how to get the identified silk resource to create a sufficient crushing force. The higher level problem is a Productivity (desire to kill prey) versus Amount of Substance (the spider has no poisoning capability) conflict. It is resolved by finding a new use for the web silk (Principle 25B, Self-Service). At the more detailed level, the conflict centres around the need to create a high crushing Force without changing or impeding the Stability and Strength of the silk. The breakthrough solution then lies in the combined strategy of many turns of the silk using its natural propensity to shrink as it dries (Principles 5, Merging and 8, 'Prior Counter-Action').

2.4. Gannet - the gannet is a large seabird renowned for its diving behaviour. The bird is known to dive to depths of over 20m by making a vertical dive into the sea from high altitude. An obvious problem here is the enormous forces inflicted on the bird's skull as it enters the water. The obvious solution is to re-enforce the skull so that it can withstand such forces. But the weight of a heavily re-enforced skull takes up valuable material resource and makes it difficult to achieve balance during non-diving flight. The gannet changed the force-versus-weight game. It has a skull that is no heavier than birds of comparable size thanks to a design full of air pockets that cushion the brain and dissipates the impact shock-waves. The gannet evolution story presents a classic illustration of the Principle 31, 'Porous Materials' strategy.

2.5. Leaf-Cutter Ant - from South America, Atta sexdens, has incredibly resilient cuticle at the cutting edges of its mandibles (Figure 7). Atta lives in the tropics, where it harvests vast amounts of vegetation to cultivate an edible fungus. It has some of the toughest teeth in the whole of the biological world. Recent studies (Reference 13), we have begun to reveal the remarkable composition and chemistry which underlies the unique toughness and durability of the teeth. A measured six-fold increase in hardness at the cutting-edge of the jaw can be traced to impregnation with zinc and manganese at levels up to 10% by weight.

Figure 7: Close-Up view of leaf cutter ant mandibles

Here is another classic material system trade-off involving the thickness of the tooth - we want it to be thick for strength and durability and thin for ease of cutting and thus lowest use of energy. The inclusion of zinc represents the use of a Principle 40, 'Composite Material' strategy.

3. Putting it all together

According to Reference 14, the original intention as far as our biological research programme is concerned was to create and publish a completely new Matrix. In that paper we discussed the Matrix Parameters - actually a subset of the classical TRIZ tool - that were most relevant in the biological context. That paper was originally published in 2004. At that time it was felt that the strategies used by nature to resolve contradictions were considerably different to those used by engineers, and that that was therefore the justification for publishing a new version of the tool.

Almost everything that has happened since that paper was first published has served to highlight two important issues:

1) at some time or another nature has sought to challenge technical contradictions involving all 48 of the Parameters found in the updated TRIZ Matrix, 'Matrix 2003' (Reference 15). The value of selecting a natural world subset of Parameters was thus diminished.

2) When we map solution strategies used by nature onto that Matrix, the correlation between the strategy used by nature and the Inventive Principles observed in the world of technology is very high. In fact as a global average across all of the boxes in the Matrix, the correlation is about 95%. It is 95% likely, in other words, that the Matrix will already contain a strategy found in nature.

Bearing in mind that Matrix 2003 was shown to be 95% accurate when tested against patents granted in 2004 (Reference 16) and is still 93% accurate when a similar exercise was conducted in 2005, the justification for creating a separate tool based on the biological findings becomes rather less compelling.

This being said, a 95% average correlation does not mean that every box in the Matrix carries a similar level of accuracy. The worst correlation in fact occurs in the Amount Of Substance versus Strength box reported in Reference 14. The correlation between Matrix and nature for this conflict pair is 60% - Matrix 2003 containing 3 of the 5 most frequently used strategies in biology. As far as the case studies described in this paper are concerned, only one - the Skomer rabbit - conflicts with the recommendations already found in Matrix 2003. And having said that, the only reason Matrix 2003 does not contain a Principle 23 recommendation for the conflict pair solved by the rabbit is that adding feedback is a strategy that is now used so frequently that we cease to think of it as inventive in many situations. The low cost with which feedback can be added to almost any technical system means that almost all such systems have feedback as a matter of course. Here is an area, in other words, where human engineers have little to learn from a solution evolved in nature.

When the time comes to review and update Matrix 2003 (we promised ourselves that it would happen when its accuracy dropped below 90%) we will undoubtedly incorporate the findings from our biological research. While it is not yet clear precisely what form such an integration will take, we are clear on two issues that can be described here:

3.1. Some jumps are bigger than others...

Nature, the great optimizer, has to produce viable life-forms. When making a discontinuous jump from one way of doing things to another, there is no middle ground. This is classic 'you can't cross a chasm using many small steps' territory. Engineers, on the other hand, don't mind too much if an experiment fails. We can make mistakes and those mistakes frequently serve the useful purpose of accelerating our discovery of the big jump solution. A classic example of a 'big jump' in a technical system would be one involving Principle 28, Mechanics Substitution. Replacing a mechanical wheel with a magnetic levitation system, gives a good illustration of a high magnitude chasm-like jump. Such jumps are rare if found at all in nature. More typical of a natural world evolutionary 'jump' is the curlew. This example, described in more detail in Reference 17, attempts to explain why some wading birds have bills that point up, while others have bills that point down (Figure 8)

Both the Curlew and the Godwit have at some point in their evolution that there is an advantage in making use of curvature (Principle 14) in improving their feeding efficiency. Transforming a straight thing into a curved thing is a relatively easy thing to do in evolutionary terms. Once that jump has occurred the rest - the direction and degree of curvature for example - is pure optimization to suit the prevailing circumstances. Likewise, changing colour is a relatively easy mutation to make. Especially if, as in the case of the earlier Peppered moth description, there is already a mutation that has created the capability to produce black spots on the normally pale coloured wings.

Eurasian Curlew (Numenius arquata ) Bar-tailed Godwit (Limosa lapponica)

Figure 8: Upward and downward curved bills in wading birds

Nature, in other words, provides us with a mechanism to identify which of the Inventive Principles found in TRIZ are likely to give bigger advances than others.

3.2. Nature knows how to deploy some principles better than engineers...

The converse of the Principle-weighting story is that there are certain breakthrough strategies that nature has deployed far more successfully than the best of mankind's efforts. By some considerable distance in front in this regard are Principle 31, 'Porous Materials' and Principle 25, 'Self-Service'. With Principle 31, the breakthrough potential comes with the profound knowledge of how to get the most functional benefit out of the least amount of material. Making use of empty space is a trick that nature has learned time and time again. Human engineers are only just beginning to learn how nature uses this strategy (and also how nature manages to combine it with other strategies - like Asymmetry). Principle 25 is important for similar reasons. Human engineers (especially ones working in the West!) have traditionally been very wasteful of resources. In nature, there is no such thing as waste. Everything gets used. If not by one part of an eco-system then by another. There are examples of nature evolving wonderful solutions using both of these strategies in just about every box in the Contradiction Matrix. While we wait for the details of precisely where and how, a simple but potentially significant way to adopt the best of nature into our desire to create breakthrough engineering systems is to always be on the look-out for opportunities to deploy these two Principles in nature-like ways.

4. References

1) Margulis, L., Sagan, D., (2000), 'What Is Life? The Eternal Enigma', University Of California Press.

2) Mackenzie, A., Ball, A.S., Virdee, S.R., (1988), 'Instant Notes In Ecology', Bios Scientific Publishers, Oxford.

3) Breitenmoser, U., Slough, B.G. and Ch. Breitenmoser-Wursten, (1993), 'Predators Of Cyclic Prey: Is The Canada Lynx Victim Or Profiteer Of The Snow Shoe Hare Cycle?' Oikov 66 issue 33:551-554.

4) Bellamy, D., 'Skomer Rabbits' Dyfed Wildlife Trust pamphlet, undated.

5) Majerus, M., (2002), 'Moths', The New Naturalist, HarperCollins, Chapter 9.

6) Mann, D.L., (2004), 'Beetles, Chains And Radar Plots', TRIZ Journal, March 2004.

7) Systematic Innovation e-zine, (2006), 'Blackback Land Crab', Issue 52, July 2006.

8) www. sy stematic -innovation. com

9) Timokhov, V., (2002), 'Natural Innovation: Examples Of Creative Problem Solving In Biology, Ecology and TRIZ', CREAX Press, (original publication in Russian, 1995).

10) Nuchter, T., Martin Benoit, M., Engel, U., Ozbek, S., Holstein, T.W., (2006), 'Nanosecond-Scale Kinetics Of Nematocyst Discharge', Current Biology, Volume 16, Issue 9, May 9.

11) Lappin, A.K., Brandt, Y., Jerry F. Husak, J.F., Macedonia, J.M., Kemp, D.J., (2006), 'Gaping Displays Reveal And Amplify A Mechanically Based Index Of Weapon Performance', The American Naturalist, University of Chicago Press, July 2006.

12) Eberhard, W., Barrantes, G., Weng, J.L., (2006), 'Tie Them Up Tight: Wrapping By Philoponella Vicina Spiders Breaks, Compresses And Sometimes Kills Their Prey', Naturwissenschaften, May;93(5):251-4.

13) University of Southampton, Bio-Composites

14) Mann, D.L., O Cathain, C., (2006), 'Better Design Using Nature's Successful (No-Compromise) Strategies', TRIZ Journal, May 2006.

15) Mann, D.L., Dewulf, S., Zlotin, B., Zusman, A., (2003), 'Matrix 2003: Updating The TRIZ Contradiction Matrix', CREAX Press.

16) Mann, D.L., (2004), 'Comparing The Classical And New Contradiction Matix, Part 2 - Zooming-In', TRIZ Journal, July 2004.

17) Systematic Innovation e-zine, (2006), 'Curlew', Issue 49, April 2006.