All posts by robertmcgrath

More on Blockchain for Supply Chains

I have written about the use of blockchain technology for provenance and supply chains. This is, indeed, a reasonable use case for blockchain technology, if not as compelling as some may think.

But in cryptoland, even the most reasonable ideas can inspire gob-smacking nonsense.

Case in point: Pindar Wong writes at Coindesk about “Blockchain’s Killer App? Making Trade Wars Obsolete” [1].  Huh, what?

This is the familiar supply chain use case.  But what does this have to do with trade wars?

Basically, I think there is a dramatic misunderstanding of what the term “Trade War” means. It means national policies that inhibit trade, especially in physical goods.  It has nothing at all to do with the technical operation of markets.

Wong wants “trade warriors” to use blockchain technology “to reduce trade friction and improve cross-border relations”.  But these frictions and relations are fundamentally political, not technical or economic.  And, tellingly, this article is in the context of strategists in Hong Kong exploring “how to fully digitize trade among the 65-plus countries involved in China’s ‘Belt and Road Initiative’.”  The B&RI is the very model of twenty first century trade war, not to mention neo-colonialism.  (I understand why HK is anxious to find a pivotal role in this initiative.)

Anyway, what is Wong actually talking about?  It’s pretty confusing.

One thing he is talking about is simplifying and automating supply chains. This is a familiar use case, though it is usually supposed to assure the provenance of goods. In this permutation, blockchains actually help trade wars, because smuggling is suppressed.

The ”trustless” blockchain requires some form of trust.  In this case, Wong describes model systems deployed in China.  Characterized as “open, bottom-up, opt-in”, they are actually Chinese government approved standards. Naturally the HK group propose extending these to the B&RI.  “Trust us, we’re from Hong Kong.”

Another innovation, indeed the biggest innovation he talks about is moving supply to demand, i.e., shipping raw materials and IP to the consumer, and manufacturing locally, on-demand.  A blockchain would be one way to keep track of the IP and return royalties and so on.  Basically, when I buy a Samsung mobile phone, it is fabricated in a local factory, and part of the sale gets credited back to Samsung via the blockchain.

This is a highly imaginative scenario, but there are a whole lot of questions. Why would an enterprise want to operate this way?  Why would a government let this be done this way?  I don’t really know.

Wong makes a good point that current WTO rules would have trouble dealing with this approach, at least initially.  But I don’t see any overwhelming difficulties.

More to the point, a blockchain is a pretty minor part of the overall picture. This entire scenario depends on some kind of international legal framework, which is the entire point of the WTO. The WTO of some successor will define the legal framework that the blockchain implements.

The whole idea of a trade war is that nation states have their own policies, which discriminate in favor of local interests. Nothing in Wong’s scenario changes this political picture. Replacing the WTO with an opaque Chinese hegemony such as the B&RI, is scarcely a realistic solution, blockchain or no blockchain.

Taking Wong’s overall point, it is interesting to think it is likely that using a blockchain does not make trade warriors “powerless”. In fact, to the degree that blockchains are transparent and trustworthy, they will make it far easier to implement discriminatory trade policies.  In short, nations will be able to use blockchain based provenance to implement “smart trade wars”.

Blockchains will actually empower a new breed of highly efficient trade warriors.

  1. Pindar Wong (2018) Blockchain’s Killer App? Making Trade Wars Obsolete. Coindesk,


Cryptocurrency Thursday

Interplanetary Copters!

The last decade has seen an incredible bloom in small autonomous and remote controlled helicopters, AKA drones. It isn’t far wrong to call them ubiquitous, and probably the characteristic technology of the 2010s. (Sorry Siri.)

It isn’t surprising, then that NASA (the National Aeronautics and Space Admin.) has some ideas about what to do with robot helicopters.

This month it is confirmed that the next planned Mars rover will have a copter aboard [3].  (To date, this appears to be known as “The Mars Helicopter”, but surely it will need to be christened with some catchy moniker. “The Red Planet Baron”?  “The Martian Air Patrol”? “The Red Planet Express”?)

This won’t be a garden variety quad copter.  Mars in not Earth, and, in particular, Mars “air” is not Earth air. The atmosphere is thin, real thin, which means less lift.  On the other hand, gravity is less than on Earth. The design will feature larger rotors spinning much faster than Terra copters.

Operating on Mars will have to be autonomous, and the flying conditions could be really hairy. Martian air is not only thin, it is cold and dusty.  And the terrain is unknown.  The odds of operating without mishap are small. The first unexpected sand storm, and it may be curtains for the flyer.  Mean time to failure may be hours or less.

Limits of power and radios means that the first mission will be short range. Unfortunately, a 2 kilo UAV will probably only do visual inspections of the surface, albeit with an option for tight close ups.  Still it will extend the footprint of the rover by quite a bit, and potentially enable atmospheric sampling.

This isn’t the only extraterrestrial copter in the works.  If Mars has a cold, thin atmosphere, Saturn’s moon Titan may have methane lakes and weather, and possibly an ocean under the icy surface.   Titan also has a cold thick atmosphere, and really low gravity—favorable for helicopters!

Planning for a landing on this intriguing world is looking at a copter, called “Dragonfly” [1, 2]. The Dragonfly design is a bit larger, and is an octocopter. <<link>>  (It is noted that it should be able to continue to operate even if one or more rotors break.)  Dragonfly is also contemplated to have a nuclear power source—Titan is too far away for solar power to be a useful option.

Titan is a lot farther away than Mars, and communications will be difficult due to radiation and other interference.  The Dragonfly will have to be really, really autonomous.

Flying conditions on Titan are unknown, but theoretically could include clouds, rain, snow, storms, who knows.  The air is methane and hydrocarbons which could gum up the flyer. Honestly, mean time to failure could be zero—it may not be able to even take off.

Both these copters are significantly different from what you might buy at the hobby store or build in your local makerspace.  But prototypes can be flown on Earth, and the autonomous control algorithms are actually not that different from Earth bound UAVs. This is a good thing, because we have to program them here, before we actually send them off.

In fact, I think this is one of the advantages of small helicopters for this use. Flying is flying, once you adjust for pressure, density, etc. It’s probably not as tricky as driving on unknown terrain.  We should be able to design autonomous software that works OK on Mars and Titan.  (Says Bob, who doesn’t have to actually make it work.)

Finally, I’ll note that a mission to Titan should ideally include an autonomous submarine or better, a tunneling submarine, to explore the lakes and cracks. I’m sure this is under study, but I don’t know that it will be possible on the first landing.

  1. Evan Ackerman, How to Conquer Titan With a Nuclear Quad Octocopter, in IEEE Spectrum – Automation. 2017.
  2. Dragonfly. Dragonfly Titan Rotorcraft Lander. 2017,
  3. Karen Northon, Mars Helicopter to Fly on NASA’s Next Red Planet Rover Mission, in NASA News Releases. 2018.


We must go to Titan! We must go to Europa!

Ice Worlds, Ho!

Robot Wednesday

Roman Lead Pollution in Greenland Ice Cores

While it lasts, the ancient ice of Earth contains a record of the atmosphere, containing tiny bubbles of air, as well as whatever was in the air, including pollen and volcanic ash.  Ice also preserves traces of human activity, AKA pollution.

This spring an international team reports on a careful study of the chemistry of 423 meters of ice cores from Greenland, which they date to run from 1200 BCE to 1200 CE, some 2500 years [1].

The measurement found fluctuating traces of lead and copper apparently dating to historical times.  Given the location of Greenland, these metals presumably reflect emissions into the atmosphere from Europe.  The new study corroborate earlier isotopic analyses, showing that prevailing winds would transport emissions from ancient European activity to Greenland, while other putative sources would have little representation in Greenland ice. The study also compared the temporal patterns to lead traces in peat bogs, and found them to match.

The lead particulates are hypothesized to be from silver lead mining activity, in which high temperature smelting used lead as part of the process of recovering silver.  The process would have emitted lead into the air at major mining sites, such as Spain.  These would blow to Greenland, leaving a record of the mining activities in the ice.

While the record is variable and uncertain, there are periods of sustained high levels of lead in the record.  These were found to correllate with overall economic activity and presumably the intensity of mining.

The researchers report swings in mining that match recorded wars in Spain, which they argue reflects the disruption and intensification of silver mining due to political developments.

“The repeated pattern of dips in production coinciding with the outbreak of wars primarily affecting the Iberian Peninsula, and then recovery again after the end of each war, suggests that warfare caused major interruptions to lead–silver production during the middle and late Roman Republic.” (p. 2)

The sustained peace of Pax Romana is detectable in a long period of high lead levels in the Greenland ice, which ends at the time of a great plague.  This period probably reflects emissions from a number of sites in Northern Europe besides Spain. This peak drops off around 9CE, “coincident with Roman abandonment of territory to the east of the Rhine, including the Sauerland mines, after three legions were annihilated in the Teutoburg forest.” (p. 3)

The activity remained low until circa 800CE, a time when mining was intensified in medieval France and Britain. There is an earlier spike that is attributed to Phoenician activity, though there is no detailed record of mining in that period.

Finally, they find that these fluctuations in lead pollution tracked the metal content of Roman currency. Drops in the lead in Greenland correspond to periods of lower silver content in coins, presumably due to low production from silver mines.

“The fluctuations in lead–silver mining and smelting indicated by the Greenland lead pollution record and estimated lead emissions were directly reflected in the fineness and metallurgy of Rome’s silver coinage, the denarius…” (p. 3)

This is a pretty cool study, and the detailed dating of the records is pretty impressive.  Cross referencing peat bogs, volcanic activity, and historical records is a good idea, though I worry that the study is combining multiple imperfect measurements, hoping the combination is better rather than worse.

A key of the study is the simulation of the atmospheric deposition, and I worry that it is logically circular.  This kind of simulation is tricky under any circumstance, and projecting thousands of years into the past is problematic. The researchers are well aware of this, and are reasonably careful about how they use the simulations. They look at general circulation patterns, not short term events, projecting from the last century of detailed data reports.

There are two questions that nag me about though.  First, there is an assumption that the general circulation is basically unchanged over the last 3000 years. I’m not sure that is true, but it may well be true for the effects of interest in this study (i.e., wind blown particles transported from Europe to Greenland).  I simply don’t know. If there was a big enough change in wind patterns during the period, this could show up as a drop in lead that has nothing to do with mining activity.

The study makes a number of claims about the sensitivity of the Greenland ice record to sources in different geographical locations (Figure 1 in the paper).  Mostly, this is a matter of distance, which is straightforward.  But they also find some substantial differences in locations not that far apart (Spain versus Britain versus  Germany), from which they infer proportionate responsibility for the lead pollution.

Essentially, they work backward from the measured lead to various potential sources where ancient mining was known to have occurred. Granting these calculations are mainly correct, they are mainly looking at known sources from the historical and archaeological record. If there are other sources, they would be difficult to detect in this methodology, and they would be misestimating the contributions of the known sources. If there are other mines unaccounted for, the whole result could be way off.

Future work may be able to extract detailed isotope composition from the deposits, which might reveal the sources more directly. I fear that that will be difficult to achieve from these ice cores.

These simulations are aligned with known history, but that is (literally) post hoc reasoning. Basically, they are able to find explanatory events for major changes in the lead pollution, including at least one surprise (i.e., the outsized effects of the Antonine plague, among sever plagues and wars).  Yet there are plenty of other events that do not show up in the lead pollution record.  I would note that the history of the metallic content of Roman coins is complicated, and not necessarily tied to the production of silver as the key factor.

In short, the perceived correlation between the ice core records and historical events is self-confirming.  Who knows how many alternative events might be chosen that do not match the ice cores as well?

In any case, the study doesn’t actually reveal any new findings. It shows that ancient industrial activity may well be reflected in Greenland ice, and that pollution seems to be correlated with the overall mining activity in Europe and the Mediterranean (but not China or other more distant locals). In fact, it would be surprising if this were not true.

What the study does seem to prove is that methods have improved to be able to at least provide detailed support for this kind of historical hypothesis, even if it isn’t really able to confirm or deny detailed hypotheses.

  1. Joseph R. McConnell, Andrew I. Wilson, Andreas Stohl, Monica M. Arienzo, Nathan J. Chellman, Sabine Eckhardt, Elisabeth M. Thompson, A. Mark Pollard, and Jørgen Peder Steffensen, Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity. Proceedings of the National Academy of Sciences, 2018.

Invisible Data Encoding with “Fontcode”

I’ve always been fond of steganography, and also printed bar and QR codes.  It so cool to encode text in non-human readable forms.  In your face and, by the way, off-line and hard to hack.  It’s not terribly useful, but it is a great reminder that what your puny human eyes see is hardly all there is out there.

This summer researchers at Columbia University report on a new variation on this theme, FontCode (preprint [2]). Combining concepts from steganography (encoding text in other text) with bar codes (encoding digital messages in printed patterns), FontCode encodes data via subtle changes to the glyphs of a digital font.

The secret code is embedded in the shape of the letters. The document is still useable, and probably looks the same to the human reader.  But the data can be retrieved either from the digital document or by scanning the visual version.


The technique is actually quite interesting.  Digital fonts are collections of glyphs, each glyph is a digital representation of how to render one character supported by the font.  The research builds on cool technique that creates a “low dimensional font manifold”—a geometric space where each point is one glyph.  (Do I personally grok this technique?  No, not at all.)

“Taking as input a collection of existing font files, their method creates a low-dimensional font manifold for every character—including both alphabets and digits—such that every location on this manifold generates a particular glyph of that character.” ([2], p.1)

They use this manifold to create a codebook of variant glyphs, a matrix of subtly different “a’s”, “b’s”, etc. Data is encoded by inserting the i-th glyph to represent the number i.  To read the data, they use techniques from OCR to isolate individual characters, and a neural network trained to discern glyphs from the codebook.

The research also involved quite a bit of work on error detection, and some studies to assess that the variant characters are not too noticeable to human readers.

Nice work.  (This work will be presented at SIGGRAPH in August.)

The authors note that this can be used as an alternative to QR codes, and is a lot less visually distracting.  While there is some advantage to having a big, ugly QR square visible in content—it signals that there is digital data here—often it would be nice to embed the information more subtly.

Obvious use cases would be for unobtrusively embedding metadata, and as a form a watermark to authenticate the document.  Of course, this could be used as a covert channel as well.  You could try to sneak information in or out of an airgap via an innocent looking document.  Or there might be a phishing attack embedded in a document. Sigh.

While this is pretty useless for advertising, it would be a method of embedding nasty trackers into non-digital adverts.  Ick!

On a cultural note, there has been a lot of hand wringing about the death of handwriting—people use digital text so much that handwriting skills are atrophying or not even learned in the first place.

Well, here is a reason to use hand written documents—they cannot contain this kind of embedded data. So let’s all work on our calligraphy (and possibly sign language), so we can pass messages that we know are baggage free.

  1. Charles Q. Choi, Hiding Information in Plain Text, in IEEE Spectrum – Tech Talk. 2018.
  2. Chang Xiao, Cheng Zhang, and Changxi Zheng, FontCode: Embedding Information in Text Documents using Glyph Perturbation. arxive, 2017.


Book Review: “Adjustment Day” by Chuck Palahiuk

Adjustment Day by Chuck Palahniuk

Ouch.  Palahniuk’s stories are never easy reading.  He’s gotten inside violence, porn, and even being damned to hell.

His new novel gets inside the wilder fantasies of the Internet, confused and violent ideologies obsessed with white and male identity. It might be satire, but it cuts awfully close to the bone. However crazy, it’s all far, far too real to easily laugh at.

The “day” in question refers to a mass uprising in which thousands of (mostly white) men gun down politicians, celebrities, teachers, and anyone on “The List”.  The List was crowd sourced on the Internet, essentially voting for “America’s least wanted”.

After Adjustment Day, the shooters take over and create a new political order, sorted by “identity”: the “formerly united states” split into separate nations for “whites”, “blacks”, and “gays”.  Everyone who doesn’t fit one of these identities are deported or worse.

And so on.  A new political correctness. Authoritarian government.

It’s grim and ugly, but Palahniuk does a pretty good job of making it psychologically real. We kind of get where people are coming from, and how they might get to this point.  Interestingly, the only overt “preaching” is all from the point of view of the uprising.  If you come away from this book rejecting the alt-right-y ideology of the new order, it’s not because Palahniuk told you you should.  It’s because the new order is so repulsive and/or idiotic in such obvious ways.

Inevitably, ironies abound.  This rebellion against an incompetent, corrupt and unfair culture leads instantly to a new incompetent, corrupt and unfair culture. Naïve concepts about cultural identity quickly run afoul of messy reality.  Forcing everyone into one of three groups doesn’t handle all the weird cases.

Anyway, this book certainly isn’t intended to be a blue print.  And I hope no one takes it as one, because it won’t work.

This story is basically a detailed elaboration of popular fantasies.  For that reason, much of the detail makes no sense at all and couldn’t happen.  The uprising is unimaginably uniformly successful, which is not very plausible.  There is no resistance at all, which is a pipe dream.  Even after months, there is neither resistance nor disunity among the revolutionaries. Not likely.  And so on.

And, above all else, I had to wonder why no outside power steps in.  I mean, there are plenty of powers in the world that would waltz into a crippled and retrogressing America.  For that matter, deporting all the Jews, Asians, and Mexicans would hardly go without response from Israel or Mexico and everyone, would it?

I think Palahniuk himself is sensitive to the possibility that people will read his satire as a real, and  worse, try to live it out.  His earlier novel Fight Club (or at least the movie version) is much beloved by the “men’s movement”, and inspires some to live out its twisted ethos.  I don’t think he   meant for that to happen.

Perhaps this novel is an attempt to partially mitigate the mischief he inadvertently caused by Fight Club. It may be significant that in Adjustment Day he names Flight Club in the context of other literature that inspires the revolution, and he implies that it is misinterpreted by these goof balls.

While it’s hard to say that I exactly enjoyed this novel, I’m glad I read it.  It’s good, at least in the Chuck Palahniuk mode, which ain’t pretty at all.

  1. Chuck Palahniuk, Adjustment Day, New York, W. W. Norton & Company, 2018.


Book Review: “Failure is an Option” by H. Jon Benjamin

Failure is an Option by H. Jon Benjamin

I only know Benjamin as the voice of Archer on the awesome TV show of that name.  (Bad Guy:  “Don’t try anything stupid.”  Archer:I don’t have to try.”)  As far as I can tell, that series is the apex of his career.

The book is a humorous autobiography, recounting all the failures in his life. The details of his life are specific, growing up Jewish in the 1970s in a small town in Massachusetts.  But the stories are universal enough. Most people have had trials and failures in their life; Benjamin spins these episodes into anti-Aesop fables, with the lesson that failure is not only an option, but the most likely outcome.

There is some good stuff here.  There is a lot of not especially great stuff here.  And the stomach ailment in Pasadena was far more than I need.

Overall, it’s a pretty thin book.

I wish it were deliberately an ironic “failure”, to fit the joke.  But I think it’s just a not particularly successful attempt.

I still love Archer, and Benjamin is a great fit for the part.

  1. H. Jon Benjamin, Failure is an Option: An Attempted Memoir, New York, Penguin, 2018.


Sunday Book Reviews


Sitting on Dinosaur Nests

It has long been known that many species of dinosaurs laid eggs. Eggs and eggshells have been found, sometimes with identifiable embryos.  And nests have been found with strong evidence of parental minding.  We don’t know all the different ways dinosaurs may have built nests and tended their eggs, but we know that some made nests on the ground and apparently sat on the eggs similar to modern birds.

Of course, modern birds are relatively small and light compared to their theropod ancestors. Sitting on eggs is a delicate matter, so how would a half-ton mama manage it?

This month an international team reports a study of dinosaur nests which suggests that many species sat on their nests, even very large animals [2].  The trick is how the nest is arranged.

The study examined well preserved fossil nests of several related species ranging from approximately 40 kg to 1500 kg in body weight.  For comparison, a contemporary ostrich will weigh about 100 kg, so these animals ranged much larger than birds.

All the species in this family laid eggs in a circle, with a mound in the middle and a ditch around the outside. The nests in this study were mostly open, i.e., were not buried as with modern crocodiles. As might be expected, the larger species laid larger eggs which probably had thicker and stronger shells. However, eggshells cannot be too strong, or the baby can’t get out, so even the bigger eggs would be fragile.

Regardless of nest size, all eggs are inclined and arranged in a radial pattern within a ring-shaped clutch “ ([2], p.3)

The key finding is that the outer ditch and center mound were larger in the larger species. That is, larger animals laid their (generally larger) eggs in a larger diameter circle, with more room in the middle.  This makes sense, assuming that the center area was a place where the parent could stand and sit.

Image caption Illustration: nesting behaviours of large and small oviraptorosaurs Image credit: Masato Hattori. [From BBC]
The authors note that this adaptation is not seen in contemporary birds. They speculate that this arrangement may have meant less contact with the eggs for the larger animals, which may be less advantageous than other styles, including the nesting styles of contemporary birds.  Perhaps this factor selects for relatively small body size accompanied by sitting directly on eggs in the next.

By the way, other investigations suggest that these eggs were probably blue-green.

  1. Mary Halton, Dinosaur parenting: How the ‘chickens from hell’ nested, in BBC News -Science & Environment. 2018.
  2. Kohei Tanaka, Darla K. Zelenitsky, Junchang Lü, Christopher L. DeBuhr, Laiping Yi, Songhai Jia, Fang Ding, Mengli Xia, Di Liu, Caizhi Shen, and Rongjun Chen, Incubation behaviours of oviraptorosaur dinosaurs in relation to body size. Biology Letters, 14 (5) 2018.