Saturday, December 13, 2014

Reading List: The Science of Interstellar

Thorne, Kip. The Science of Interstellar. New York: W. W. Norton, 2014. ISBN 978-0-393-35137-8.
Christopher Nolan's 2014 film Interstellar was eagerly awaited by science fiction enthusiasts who, having been sorely disappointed so many times by movies that crossed the line into fantasy by making up entirely implausible things to move the plot along, hoped that this effort would live up to its promise of getting the science (mostly) right and employing scientifically plausible speculation where our present knowledge is incomplete.

The author of the present book is one of the most eminent physicists working in the field of general relativity (Einstein's theory of gravitation) and a pioneer in exploring the exotic strong field regime of the theory, including black holes, wormholes, and gravitational radiation. Prof. Thorne was involved in the project which became Interstellar from its inception, and worked closely with the screenwriters, director, and visual effects team to get the science right. Some of the scenes in the movie, such as the visual appearance of orbiting a rotating black hole, have never been rendered accurately before, and are based upon original work by Thorne in computing light paths through spacetime in its vicinity which will be published as professional papers.

Here, the author recounts the often bumpy story of the movie's genesis and progress over the years from his own, Hollywood-outsider, perspective, how the development of the story presented him, as technical advisor (he is credited as an executive producer), with problem after problem in finding a physically plausible solution, sometimes requiring him to do new physics. Then, Thorne provides a popular account of the exotic physics on which the story is based, including gravitational time dilation, black holes, wormholes, and speculative extra dimensions and “brane” scenarios stemming from string theory. Then he “interprets” the events and visual images in the film, explaining (where possible) how they could be produced by known, plausible, or speculative physics. Of course, this isn't always possible—in some cases the needs of story-telling or the requirement not to completely baffle a non-specialist with bewilderingly complicated and obscure images had to take priority over scientific authenticity, and when this is the case Thorne is forthright in admitting so.

Sections are labelled with icons identifying them as “truth”: generally accepted by those working in the field and often with experimental evidence, “educated guess”: a plausible inference from accepted physics, but without experimental evidence and assuming existing laws of physics remain valid in circumstances under which we've never tested them, and “speculation”: wild and wooly stuff (for example quantum gravity or the interior structure of a black hole) which violates no known law of physics, but for which we have no complete and consistent theory and no evidence whatsoever.

This is a clearly written and gorgeously illustrated book which, for those who enjoyed the movie but weren't entirely clear whence some of the stunning images they saw came, will explain the science behind them. The cover of the book has a “SPOILER ALERT” warning potential readers that the ending and major plot details are given away in the text. I will refrain from discussing them here so as not to make this a spoiler in itself. I have not yet seen the movie, and I expect when I do I will enjoy it more for having read the book, since I'll know what to look for in some of the visuals and be less likely to dismiss some of the apparently outrageous occurrences by knowing that there is a physically plausible (albeit extremely speculative and improbable) explanation for them.

For the animations and blackboard images mentioned in the text, the book directs you to a Web site which is so poorly designed and difficult to navigate it took me ten minutes to find them on the first visit. Here is a direct link. In the Kindle edition the index cites page numbers in the print edition which are useless since the electronic edition does not contain real page numbers. There are a few typographical errors and one factual howler: Io is not “Saturn's closest moon”, and Cassini was captured in Saturn orbit by a propulsion burn, not a gravitational slingshot (this does not affect the movie in any way: it's in background material).

Posted at 22:38 Permalink

Saturday, December 6, 2014

Reading List: A Troublesome Inheritance

Wade, Nicholas. A Troublesome Inheritance. New York: Penguin Press, 2014. ISBN 978-1-59420-446-3.
Geographically isolated populations of a species (unable to interbreed with others of their kind) will be subject to natural selection based upon their environment. If that environment differs from that of other members of the species, the isolated population will begin to diverge genetically, as genetic endowments which favour survival and more offspring are selected for. If the isolated population is sufficiently small, the mechanism of genetic drift may cause a specific genetic variant to become almost universal or absent in that population. If this process is repeated for a sufficiently long time, isolated populations may diverge to such a degree they can no longer interbreed, and therefore become distinct species.

None of this is controversial when discussing other species, but in some circles to suggest that these mechanisms apply to humans is the deepest heresy. This well-researched book examines the evidence, much from molecular biology which has become available only in recent years, for the diversification of the human species into distinct populations, or “races” if you like, after its emergence from its birthplace in Africa. In this book the author argues that human evolution has been “recent, copious, and regional” and presents the genetic evidence to support this view.

A few basic facts should be noted at the outset. All humans are members of a single species, and all can interbreed. Humans, as a species, have an extremely low genetic diversity compared to most other animal species: this suggests that our ancestors went through a genetic “bottleneck” where the population was reduced to a very small number, causing the variation observed in other species to be lost through genetic drift. You might expect different human populations to carry different genes, but this is not the case—all humans have essentially the same set of genes. Variation among humans is mostly a result of individuals carrying different alleles (variants) of a gene. For example, eye colour in humans is entirely inherited: a baby's eye colour is determined completely by the alleles of various genes inherited from the mother and father. You might think that variation among human populations is then a question of their carrying different alleles of genes, but that too is an oversimplification. Human genetic variation is, in most cases, a matter of the frequency of alleles among the population.

This means that almost any generalisation about the characteristics of individual members of human populations with different evolutionary histories is ungrounded in fact. The variation among individuals within populations is generally much greater than that of populations as a whole. Discrimination based upon an individual's genetic heritage is not just abhorrent morally but scientifically unjustified.

Based upon these now well-established facts, some have argued that “race does not exist” or is a “social construct”. While this view may be motivated by a well-intentioned desire to eliminate discrimination, it is increasingly at variance with genetic evidence documenting the history of human populations.

Around 200,000 years ago, modern humans emerged in Africa. They spent more than three quarters of their history in that continent, spreading to different niches within it and developing a genetic diversity which today is greater than that of all humans in the rest of the world. Around 50,000 years before the present, by the genetic evidence, a small band of hunter-gatherers left Africa for the lands to the north. Then, some 30,000 years ago the descendants of these bands who migrated to the east and west largely ceased to interbreed and separated into what we now call the Caucasian and East Asian populations. These have remained the main three groups within the human species. Subsequent migrations and isolations have created other populations such as Australian and American aborigines, but their differentiation from the three main races is less distinct. Subsequent migrations, conquest, and intermarriage have blurred the distinctions between these groups, but the fact is that almost any child, shown a picture of a person of European, African, or East Asian ancestry can almost always effortlessly and correctly identify their area of origin. University professors, not so much: it takes an intellectual to deny the evidence of one's own eyes.

As these largely separated populations adapted to their new homes, selection operated upon their genomes. In the ancestral human population children lost the ability to digest lactose, the sugar in milk, after being weaned from their mothers' milk. But in populations which domesticated cattle and developed dairy farming, parents who passed on an allele which would allow their children to drink cow's milk their entire life would have more surviving offspring and, in a remarkably short time on the evolutionary scale, lifetime lactose tolerance became the norm in these areas. Among populations which never raised cattle or used them only for meat, lifetime lactose tolerance remains rare today.

Humans in Africa originally lived close to the equator and had dark skin to protect them from the ultraviolet radiation of the Sun. As human bands occupied northern latitudes in Europe and Asia, dark skin would prevent them from being able to synthesise sufficient Vitamin D from the wan, oblique sunlight of northern winters. These populations were under selection pressure for alleles of genes which gave them lighter skin, but interestingly Europeans and East Asians developed completely different genetic means to lighten their skin. The selection pressure was the same, but evolution blundered into two distinct pathways to meet the need.

Can genetic heritage affect behaviour? There's evidence it can. Humans carry a gene called MAO-A, which breaks down neurotransmitters that affect the transmission of signals within the brain. Experiments in animals have provided evidence that under-production of MAO-A increases aggression and humans with lower levels of MAO-A are found to be more likely to commit violent crime. MAO-A production is regulated by a short sequence of DNA adjacent to the gene: humans may have anywhere from two to five copies of the promoter; the more you have, the more the MAO-A, and hence the mellower you're likely to be. Well, actually, people with three to five copies are indistinguishable, but those with only two (2R) show higher rates of delinquency. Among men of African ancestry, 5.5% carry the 2R variant, while 0.1% of Caucasian males and 0.00067% of East Asian men do. Make of this what you will.

The author argues that just as the introduction of dairy farming tilted the evolutionary landscape in favour of those bearing the allele which allowed them to digest milk into adulthood, the transition of tribal societies to cities, states, and empires in Asia and Europe exerted a selection pressure upon the population which favoured behavioural traits suited to living in such societies. While a tribal society might benefit from producing a substantial population of aggressive warriors, an empire has little need of them: its armies are composed of soldiers, courageous to be sure, who follow orders rather than charging independently into battle. In such a society, the genetic traits which are advantageous in a hunter-gatherer or tribal society will be selected out, as those carrying them will, if not expelled or put to death for misbehaviour, be unable to raise as large a family in these settled societies.

Perhaps, what has been happening over the last five millennia or so is a domestication of the human species. Precisely as humans have bred animals to live with them in close proximity, human societies have selected for humans who are adapted to prosper within them. Those who conform to the social hierarchy, work hard, come up with new ideas but don't disrupt the social structure will have more children and, over time, whatever genetic predispositions there may be for these characteristics (which we don't know today) will become increasingly common in the population. It is intriguing that as humans settled into fixed communities, their skeletons became less robust. This same process of gracilisation is seen in domesticated animals compared to their wild congeners. Certainly there have been as many human generations since the emergence of these complex societies as have sufficed to produce major adaptation in animal species under selective breeding.

Far more speculative and controversial is whether this selection process has been influenced by the nature of the cultures and societies which create the selection pressure. East Asian societies tend to be hierarchical, obedient to authority, and organised on a large scale. European societies, by contrast, are fractious, fissiparous, and prone to bottom-up insurgencies. Is this in part the result of genetic predispositions which have been selected for over millennnia in societies which work that way?

It is assumed by many right-thinking people that all that is needed to bring liberty and prosperity to those regions of the world which haven't yet benefited from them is to create the proper institutions, educate the people, and bootstrap the infrastructure, then stand back and watch them take off. Well, maybe—but the history of colonialism, the mission civilisatrice, and various democracy projects and attempts at nation building over the last two centuries may suggest it isn't that simple. The population of the colonial, conquering, or development-aid-giving power has the benefit of millennia of domestication and adaptation to living in a settled society with division of labour. Its adaptations for tribalism have been largely bred out. Not so in many cases for the people they're there to “help”. Withdraw the colonial administration or occupation troops and before long tribalism will re-assert itself because that's the society for which the people are adapted.

Suggesting things like this is anathema in academia or political discourse. But look at the plain evidence of post-colonial Africa and more recent attempts of nation-building, and couple that with the emerging genetic evidence of variation in human populations and connections to behaviour and you may find yourself thinking forbidden thoughts. This book is an excellent starting point to explore these difficult issues, with numerous citations of recent scientific publications.

Posted at 15:23 Permalink

Sunday, November 30, 2014

Reading List: The Martian

Weir, Andy. The Martian. New York: Broadway Books, [2011] 2014. ISBN 978-0-553-41802-6.
Mark Watney was part of the six person crew of Ares 3 which landed on Mars to carry out an exploration mission in the vicinity of its landing site in Acidalia Planitia. The crew made a precision landing at the target where “presupply” cargo flights had already landed their habitation module, supplies for their stay on Mars, rovers and scientific instruments, and the ascent vehicle they would use to return to the Earth-Mars transit vehicle waiting for them in orbit. Just six days after landing, having set up the habitation module and unpacked the supplies, they are struck by a dust storm of unprecedented ferocity. With winds up to 175 kilometres per hour, the Mars Ascent Vehicle (MAV), already fuelled by propellant made on Mars by reacting hydrogen brought from Earth with the Martian atmosphere, was at risk of being blown over, which would destroy the fragile spacecraft and strand the crew on Mars. NASA gives the order to abort the mission and evacuate to orbit in the MAV for an immediate return to Earth.

But the crew first has to get from the habitation module to the MAV, which means walking across the surface in the midst of the storm. (You'd find it very hard to walk in a 175 km/h wind on Earth, but recall that the atmosphere pressure on Mars is only about 1/200 that of Earth at sea level, so the wind doesn't pack anywhere near the punch.) Still, there was dust and flying debris from equipment ripped loose from the landers. Five members of the crew made it to the MAV. Mark Watney didn't.

As the crew made the traverse to the MAV, Watney was struck by part of an antenna array torn from the habitation, puncturing his suit and impaling him. He was carried away by the wind, and the rest of the crew, seeing his vital signs go to zero before his suit's transmitter failed, followed mission rules to leave him behind and evacuate in the MAV while they still could.

But Watney wasn't dead. His injury was not fatal, and his blood loss was sufficient to seal the leak in the suit where the antenna had pierced it, as the water in the blood boiled off and the residue mostly sealed the breach. Awakening after the trauma, he made an immediate assessment of his situation. I'm alive. Cool! I hurt like heck. Not cool. The habitation module is intact. Yay! The MAV is gone—I'm alone on Mars. Dang!

“Dang” is not precisely how Watney put it. This book contains quite a bit of profanity which I found gratuitous. NASA astronauts in the modern era just don't swear like sailors, especially on open air-to-ground links. Sure, I can imagine launching a full salvo of F-bombs upon discovering I'd been abandoned on Mars, especially when I'm just talking to myself, but everybody seems to do it here on all occasions. This is the only reason I'd hesitate to recommend this book to younger readers who would otherwise be inspired by the story.

Watney is stranded on Mars with no way to communicate with Earth, since all communications were routed through the MAV, which has departed. He has all of the resources for a six-person mission, so he has no immediate survival problems after he gets back to the habitation and stitches up his wound, but he can work the math: even if he can find a way to communicate to Earth that he's still alive, orbital mechanics dictates that it will take around two years to send a rescue mission. His supplies cannot be stretched that far.

This sets the stage for a gripping story of survival, improvisation, difficult decisions, necessity versus bureaucratic inertia, trying to do the right thing in a media fishbowl, and all done without committing any howlers in technology, orbital mechanics, or the way people and organisations behave. Sure, you can quibble about this or that detail, but then people far in the future may regard a factual account of Apollo 13 as largely legend, given how many things had to go right to rescue the crew. Things definitely do not go smoothly here: there is reverse after reverse, and many inscrutable mysteries to be unscrewed if Watney is to get home.

This is an inspiring tale of pioneering on a new world. People have already begun to talk about going to Mars to stay. These settlers will face stark challenges though, one hopes, not as dire as Watney, and with the confidence of regular re-supply missions and new settlers to follow. Perhaps this novel will be seen, among the first generation born on Mars, as inspiration that the challenges they face in bringing a barren planet to life are within the human capacity to solve, especially if their media library isn't exclusively populated with 70s TV shows and disco.

A Kindle edition is available.

Posted at 23:48 Permalink

Wednesday, November 26, 2014

Reading List: Liberators

Rawles, James Wesley. Liberators. New York: Dutton, 2014. ISBN 978-0-525-95391-3.
This novel is the fifth in the series which began with Patriots (December 2008), then continued with Survivors (January 2012), Founders (October 2012), and Expatriates (October 2013), These books are not a conventional multi-volume narrative, in that all describe events in the lives of their characters in roughly the same time period surrounding “the Crunch”—a grid down societal collapse due to a debt crisis and hyperinflation. Taking place at the same time, you can read these books in any order, but if you haven't read the earlier novels you'll miss much of the back-story of the characters who appear here, which informs the parts they play in this episode.

Here the story cuts back and forth between the United States, where Megan LaCroix and her sister Malorie live on a farm in West Virginia with Megan's two boys, and Joshua Kim works in security at the National Security Agency where Megan is an analyst. When the Crunch hits, Joshua and the LaCroix sisters decide to team up to bug out to Joshua's childhood friend's place in Kentucky, where survival from the urban Golden Horde may be better assured. They confront the realities of a collapsing society, where the rule of law is supplanted by extractive tyrannies, and are forced to over-winter in a wilderness, living by their wits and modest preparations.

In Western Canada, the immediate impact of the Crunch was less severe because electrical power, largely hydroelectric, remained on. At the McGregor Ranch, in inland British Columbia (a harsh, northern continental climate nothing like that of Vancouver), the family and those who have taken refuge with them ride out the initial crisis only to be confronted with an occupation of Canada by a nominally United Nations force called UNPROFOR, which is effectively a French colonial force which, in alliance with effete urban eastern and francophone Canada, seeks to put down the fractious westerners and control the resource-rich land they inhabit.

This leads to an asymmetrical war of resistance, aided by the fact that when earlier faced with draconian gun registration and prohibition laws imposed by easterners, a large number of weapons in the west simply vanished, only to reappear when they were needed most. As was demonstrated in Vietnam and Algeria, French occupation forces can be tenacious and brutal, but are ultimately no match for an indigenous insurgency with the support of the local populace. A series of bold strikes against UNPROFOR assets eventually turns the tide.

But just when Canada seems ready to follow the U.S. out of the grip of tyranny, an emboldened China, already on the march in Africa, makes a move to seize western Canada's abundant natural resources. Under the cover of a UN resolution, a massive Chinese force, with armour and air support, occupies the western provinces. This is an adversary of an entirely different order than the French, and will require the resistance, supported by allies from the liberation struggle in the U.S., to audacious and heroic exploits, including one of the greatest acts of monkey-wrenching ever described in a thriller.

As this story has developed over the five novels, the author has matured into a first-rate thriller novelist. There is still plenty of information on gear, tactics, intelligence operations, and security, but the characters are interesting, well-developed, and the action scenes both plausible and exciting. In the present book, we encounter many characters we've met in previous volumes, with their paths crossing as events unfold. There is no triumphalism or glossing over the realities of insurgent warfare against a tyrannical occupying force. There is a great deal of misery and hardship, and sometimes tragedy can result when you've taken every precaution, made no mistake, but simply run out of luck.

Taken together, these five novels are an epic saga of survival in hard and brutal times, painted on a global canvas. Reading them, you will not only be inspired that you and your loved ones can survive such a breakdown in the current economic and social order, but you will also learn a great deal of the details of how to do so. This is not a survival manual, but attentive readers will find many things to research further for their own preparations for an uncertain future. An excellent place to begin that research is the author's own survivalblog.com Web site, whose massive archives you can spend months exploring.

Posted at 23:37 Permalink

Sunday, November 23, 2014

Reading List: Undercover Mormon

Metzger, Th. Undercover Mormon. New York: Roadswell Editions, 2013.
The author, whose spiritual journey had earlier led him to dabble with becoming a Mennonite, goes weekly to an acupuncturist named Rudy Kilowatt who believes in the power of crystals, attends neo-pagan fertility rituals in a friend's suburban back yard, had been oddly fascinated by Mormonism ever since, as a teenager, he attended the spectacular annual Mormon pageant at Hill Cumorah, near his home in upstate New York.

He returned again and again for the spectacle of the pageant, and based upon his limited knowledge of Mormon doctrine, found himself admiring how the religion seemed to have it all: “All religion is either sword and sorcery or science fiction. The reason Mormonism is growing so fast is that you guys have both, and don't apologize for either.” He decides to pursue this Mormon thing further, armouring himself in white shirt, conservative tie, and black pants, and heading off to the nearest congregation for the Sunday service.

Approached by missionaries who spot him as a newcomer, he masters his anxiety (bolstered by the knowledge he has a couple of Xanax pills in his pocket), gives a false name, and indicates he's interested in learning more about the faith. Before long he's attending Sunday school, reading tracts, and spinning into the Mormon orbit, with increasing suggestions that he might convert.

All of this is described in a detached, ironic manner, in which the reader (and perhaps the author) can't decide how seriously to take it all. Metzger carries magic talismans to protect himself against the fearful “Mormo”, describes his anxiety to his psychoanalyst, who prescribes the pharmaceutical version of magic bones. He struggles with paranoia about his deception being found out and agonises over the consequences. He consults a friend who, “For a while he was an old-order Quaker, then a Sufi, then a retro-neo-pagan. Now he's a Unitarian-Universalist professor of history.”

The narrative is written in the tediously quaint “new journalism” style where it's as much about the author as the subject. This works poorly here because the author isn't very interesting. He comes across as so neurotic and self-absorbed as to make Woody Allen seem like Clint Eastwood. His “discoveries” about the content of LDS scripture could have been made just as easily by reading the original documents on the LDS Web site, and his exploration of the history of Joseph Smith and the early days of Mormonism in New York could have been accomplished by consulting Wikipedia. His antics, such as burying chicken bones around the obelisk of Moroni on Hill Cumorah and digging up earth from the grave of Luman Walter to spread it in the sacred grove, push irony past the point of parody—does anybody believe the author took such things seriously (and if he did, why should anybody care what he thinks about anything)?

The book does not mock Mormonism, and treats the individuals he encounters on his journey more or less respectfully (with just that little [and utterly unjustified] “I'm better than you” that the hip intellectual has for earnest, clean-cut, industrious people who are “as white as angel food cake, and almost as spongy.”) But you'll learn nothing about the history and doctrine of the religion here that you won't find elsewhere without all the baggage of the author's tiresome “adventures”.

Posted at 15:56 Permalink

Thursday, November 6, 2014

Reading List: Command and Control

Schlosser, Eric. Command and Control. New York: Penguin, 2013. ISBN 978-0-14-312578-5.
On the evening of September 18th, 1980 two U.S. Air Force airmen, members of a Propellant Transfer System (PTS) team, entered a Titan II missile silo near Damascus, Arkansas to perform a routine maintenance procedure. Earlier in the day they had been called to the site because a warning signal had indicated that pressure in the missile's second stage oxidiser tank was low. This was not unusual, especially for a missile which had recently been refuelled, as this one had, and the procedure of adding nitrogen gas to the tank to bring the pressure up to specification was considered straightforward. That is, if you consider any work involving a Titan II “routine” or “straightforward”. The missile, in an underground silo, protected by a door weighing more than 65 tonnes and able to withstand the 300 psi overpressure of a nearby nuclear detonation, stood more than 31 metres high and contained 143 tonnes of highly toxic fuel and oxidiser which, in addition to being poisonous to humans in small concentrations, were hypergolic: they burst into flames upon contact with one another, with no need of a source of ignition. Sitting atop this volatile fuel was a W-53 nuclear warhead with a yield of 9 megatons and high explosives in the fission primary which were not, as more modern nuclear weapons, insensitive to shock and fire. While it was unlikely in the extreme that detonation of these explosives due to an accident would result in a nuclear explosion, they could disperse the radioactive material in the bomb over the local area, requiring a massive clean-up effort.

The PTS team worked on the missile wearing what amounted to space suits with their own bottled air supply. One member was an experienced technician while the other was a 19-year old rookie receiving on the job training. Early in the procedure, the team was to remove the pressure cap from the side of the missile. While the lead technician was turning the cap with a socket wrench, the socket fell off the wrench and down the silo alongside the missile. The socket struck the thrust mount supporting the missile, bounced back upward, and struck the side of the missile's first stage fuel tank. Fuel began to spout outward as if from a garden hose. The trainee remarked, “This is not good.”

Back in the control centre, separated from the silo by massive blast doors, the two man launch team who had been following the servicing operation, saw their status panels light up like a Christmas tree decorated by somebody inordinately fond of the colour red. The warnings were contradictory and clearly not all correct. Had there indeed been both fuel and oxidiser leaks, as indicated, there would already have been an earth-shattering kaboom from the silo, and yet that had not happened. The technicians knew they had to evacuate the silo as soon as possible, but their evacuation route was blocked by dense fuel vapour.

The Air Force handles everything related to missiles by the book, but the book was silent about procedures for a situation like this, with massive quantities of toxic fuel pouring into the silo. Further, communication between the technicians and the control centre were poor, so it wasn't clear at first just what had happened. Before long, the commander of the missile wing, headquarters of the Strategic Air Command (SAC) in Omaha, and the missile's manufacturer, Martin Marietta, were in conference trying to decide how to proceed. The greatest risks were an electrical spark or other source of ignition setting the fuel on fire or, even greater, of the missile collapsing in the silo. With tonnes of fuel pouring from the fuel tank and no vent at its top, pressure in the tank would continue to fall. Eventually, it would be below atmospheric pressure, and would be crushed, likely leading the missile to crumple under the weight of the intact and fully loaded first stage oxidiser and second stage tanks. These tanks would then likely be breached, leading to an explosion. No Titan II had ever exploded in a closed silo, so there was no experience as to what the consequences of this might be.

As the night proceeded, all of the Carter era military malaise became evident. The Air Force lied to local law enforcement and media about what was happening, couldn't communicate with first responders, failed to send an evacuation helicopter for a gravely injured person because an irrelevant piece of equipment wasn't available, and could not come to a decision about how to respond as the situation deteriorated. Also on display was the heroism of individuals, in the Air Force and outside, who took matters into their own hands on the spot, rescued people, monitored the situation, evacuated nearby farms in the path of toxic clouds, and improvised as events required.

Among all of this, nothing whatsoever had been done about the situation of the missile. Events inevitably took their course. In the early morning hours of September 19th, the missile collapsed, releasing all of its propellants, which exploded. The 65 tonne silo door was thrown 200 metres, shearing trees in its path. The nuclear warhead was thrown two hundred metres in another direction, coming to rest in a ditch. Its explosives did not detonate, and no radiation was released.

While there were plenty of reasons to worry about nuclear weapons during the Cold War, most people's concerns were about a conflict escalating to the deliberate use of nuclear weapons or the possibility of an accidental war. Among the general public there was little concern about the tens of thousands of nuclear weapons in depots, aboard aircraft, atop missiles, or on board submarines—certainly every precaution had been taken by the brilliant people at the weapons labs to make them safe and reliable, right?

Well, that was often the view among “defence intellectuals” until they were briefed in on the highly secret details of weapons design and the command and control procedures in place to govern their use in wartime. As documented in this book, which uses the Damascus accident as a backdrop (a ballistic missile explodes in rural Arkansas, sending its warhead through the air, because somebody dropped a socket wrench), the reality was far from reassuring, and it took decades, often against obstructionism and foot-dragging from the Pentagon, to remedy serious risks in the nuclear stockpile.

In the early days of the U.S. nuclear stockpile, it was assumed that nuclear weapons were the last resort in a wartime situation. Nuclear weapons were kept under the civilian custodianship of the Atomic Energy Commission (AEC), and would only be released to the military services by a direct order from the President of the United States. Further, the nuclear cores (“pits”) of weapons were stored separately from the rest of the weapon assembly, and would only be inserted in the weapon, in the case of bombers, in the air, after the order to deliver the weapon was received. (This procedure had been used even for the two bombs dropped on Japan.) These safeguards meant that the probability of an accidental nuclear explosion was essentially nil in peacetime, although the risk did exist of radioactive contamination if a pit were dispersed due to fire or explosion.

As the 1950s progressed, and fears of a Soviet sneak attack grew, pressure grew to shift the custodianship of nuclear weapons to the military. The development of nuclear tactical and air defence weapons, some of which were to be forward deployed outside the United States, added weight to this argument. If radar detected a wave of Soviet bombers heading for the United States, how practical would it be to contact the President, get him to sign off on transferring the anti-aircraft warheads to the Army and Air Force, have the AEC deliver them to the military bases, install them on the missiles, and prepare the missiles for launch? The missile age only compounded this situation. Now the risk existed for a “decapitation” attack which could take out the senior political and military leadership, leaving nobody with the authority to retaliate.

The result of all this was a gradual devolution of control over nuclear weapons from civilian to military commands, with fully-assembled nuclear weapons loaded on aircraft, sitting at the ends of runways in the United States and Europe, ready to take off on a few minutes' notice. As tensions continued to increase, B-52s, armed with hydrogen bombs, were on continuous “airborne alert”, ready at any time to head toward their targets.

The weapons carried by these aircraft, however, had not been designed for missions like this. They used high explosives which could be detonated by heat or shock, often contained few interlocks to prevent a stray electrical signal from triggering a detonation, were not “one point safe” (guaranteed that detonation of one segment of the high explosives could not cause a nuclear yield), and did not contain locks (“permissive action links”) to prevent unauthorised use of a weapon. Through much of the height of the Cold War, it was possible for a rogue B-52 or tactical fighter/bomber crew to drop a weapon which might start World War III; the only protection against this was rigid psychological screening and the enemy's air defence systems.

The resistance to introducing such safety measures stemmed from budget and schedule pressures, but also from what was called the “always/never” conflict. A nuclear weapon should always detonate when sent on a wartime mission. But it should never detonate under any other circumstances, including an airplane crash, technical malfunction, maintenance error, or through the deliberate acts of an insane or disloyal individual or group. These imperatives inevitably conflict with one another. The more safeguards you design into a weapon to avoid an unauthorised detonation, the greater the probability one of them may fail, rendering the weapon inert. SAC commanders and air crews were not enthusiastic about the prospect of risking their lives running the gauntlet of enemy air defences only to arrive over their target and drop a dud.

As documented here, it was only after the end of Cold War, as nuclear weapon stockpiles were drawn down, that the more dangerous weapons were retired and command and control procedures put into place which seem (to the extent outsiders can assess such highly classified matters) to provide a reasonable balance between protection against a catastrophic accident or unauthorised launch and a reliable deterrent.

Nuclear command and control extends far beyond the design of weapons. The author also discusses in detail the development of war plans, how civilian and military authorities interact in implementing them, how emergency war orders are delivered, authenticated, and executed, and how this entire system must be designed not only to be robust against errors when intact and operating as intended, but in the aftermath of an attack.

This is a serious scholarly work and, at 632 pages, a long one. There are 94 pages of end notes, many of which expand substantially upon items in the main text. A Kindle edition is available.

Posted at 23:49 Permalink

Sunday, October 26, 2014

Floating Point Benchmark: Rust Language Added

I have posted an update to my trigonometry-intense floating point benchmark which adds Rust to the list of languages in which the benchmark is implemented. A new release of the benchmark collection including Rust is now available for downloading.

Rust is a systems programming language currently under development. It attempts to provide performance comparable to low-level programming languages such as C and C++ while avoiding common causes of crashes and security problems such as subscript and pointer errors, dangling pointers, memory leaks, and multi-thread race conditions. It is a compiled language with extensive compile-time checking which detects many errors which cause run-time errors in other languages, and has a reference-counted memory management architecture which avoids the overhead of garbage collection and provides critical section locking in multi-thread programs.

As a language actively under development, Rust is a moving target and any program developed for it may require modification as the language and run-time libraries evolve. This program was developed on version 0.13.0, and I encountered no problems with the language or libraries. Rust supports multiple programming paradigms: I chose to implement this program in a functional style with no mutable variables.

The relative performance of the various language implementations (with C taken as 1) is as follows. All language implementations of the benchmark listed below produced identical results to the last (11th) decimal place.

Language Relative
Time
Details
C 1 GCC 3.2.3 -O3, Linux
Visual Basic .NET 0.866 All optimisations, Windows XP
FORTRAN 1.008 GNU Fortran (g77) 3.2.3 -O3, Linux
Pascal 1.027
1.077
Free Pascal 2.2.0 -O3, Linux
GNU Pascal 2.1 (GCC 2.95.2) -O3, Linux
Rust 1.077 Rust 0.13.0, --release, Linux
Java 1.121 Sun JDK 1.5.0_04-b05, Linux
Visual Basic 6 1.132 All optimisations, Windows XP
Haskell 1.223 GHC 7.4.1-O2 -funbox-strict-fields, Linux
Ada 1.401 GNAT/GCC 3.4.4 -O3, Linux
Go 1.481 Go version go1.1.1 linux/amd64, Linux
Simula 2.099 GNU Cim 5.1, GCC 4.8.1 -O2, Linux
Lua 2.515
22.7
LuaJIT 2.0.3, Linux
Lua 5.2.3, Linux
Python 2.633
30.0
PyPy 2.2.1 (Python 2.7.3), Linux
Python 2.7.6, Linux
Erlang 3.663
9.335
Erlang/OTP 17, emulator 6.0, HiPE [native, {hipe, [o3]}]
Byte code (BEAM), Linux
ALGOL 60 3.951 MARST 2.7, GCC 4.8.1 -O3, Linux
Lisp 7.41
19.8
GNU Common Lisp 2.6.7, Compiled, Linux
GNU Common Lisp 2.6.7, Interpreted
Smalltalk 7.59 GNU Smalltalk 2.3.5, Linux
Forth 9.92 Gforth 0.7.0, Linux
COBOL 12.5
46.3
Micro Focus Visual COBOL 2010, Windows 7
Fixed decimal instead of computational-2
Algol 68 15.2 Algol 68 Genie 2.4.1 -O3, Linux
Perl 23.6 Perl v5.8.0, Linux
Ruby 26.1 Ruby 1.8.3, Linux
JavaScript 27.6
39.1
46.9
Opera 8.0, Linux
Internet Explorer 6.0.2900, Windows XP
Mozilla Firefox 1.0.6, Linux
QBasic 148.3 MS-DOS QBasic 1.1, Windows XP Console

This is a very impressive performance for a language whose specification continues to be refined and with a compiler under active development. There are few applications where an 8% speed penalty compared to C/C++ will make much of a difference (note, of course, that many systems programming applications do things very different that this floating-point intensive benchmark, and that relative performance measured by this program may not be indicative of what you'll experience on very different tasks such as text processing, management of large data structures, or parallel computation).

Posted at 00:31 Permalink

Saturday, October 18, 2014

Reading List: The Great Influenza

Barry, John M. The Great Influenza. New York: Penguin, [2004] 2005. ISBN 978-0-14-303649-4.
In the year 1800, the practice of medicine had changed little from that in antiquity. The rapid progress in other sciences in the 18th century had had little impact on medicine, which one historian called “the withered arm of science”. This began to change as the 19th century progressed. Researchers, mostly in Europe and especially in Germany, began to lay the foundations for a scientific approach to medicine and public health, understanding the causes of disease and searching for means of prevention and cure. The invention of new instruments for medical examination, anesthesia, and antiseptic procedures began to transform the practice of medicine and surgery.

All of these advances were slow to arrive in the United States. As late as 1900 only one medical school in the U.S. required applicants to have a college degree, and only 20% of schools required a high school diploma. More than a hundred U.S. medical schools accepted any applicant who could pay, and many graduated doctors who had never seen a patient or done any laboratory work in science. In the 1870s, only 10% of the professors at Harvard's medical school had a Ph.D.

In 1873, Johns Hopkins died, leaving his estate of US$ 3.5 million to found a university and hospital. The trustees embarked on an ambitious plan to build a medical school to be the peer of those in Germany, and began to aggressively recruit European professors and Americans who had studied in Europe to build a world class institution. By the outbreak of World War I in Europe, American medical research and education, still concentrated in just a few centres of excellence, had reached the standard set by Germany. It was about to face its greatest challenge.

With the entry of the United States into World War I in April of 1917, millions of young men conscripted for service were packed into overcrowded camps for training and preparation for transport to Europe. These camps, thrown together on short notice, often had only rudimentary sanitation and shelter, with many troops living in tent cities. Large number of doctors and especially nurses were recruited into the Army, and by the start of 1918 many were already serving in France. Doctors remaining in private practice in the U.S. were often older men, trained before the revolution in medical education and ignorant of modern knowledge of diseases and the means of treating them.

In all American wars before World War I, more men died from disease than combat. In the Civil War, two men died from disease for every death on the battlefield. Army Surgeon General William Gorgas vowed that this would not be the case in the current conflict. He was acutely aware that the overcrowded camps, frequent transfers of soldiers among far-flung bases, crowded and unsanitary troop transport ships, and unspeakable conditions in the trenches were a tinderbox just waiting for the spark of an infectious disease to ignite it. But the demand for new troops for the front in France caused his cautions to be overruled, and still more men were packed into the camps.

Early in 1918, a doctor in rural Haskell County, Kansas began to treat patients with a disease he diagnosed as influenza. But this was nothing like the seasonal influenza with which he was familiar. In typical outbreaks of influenza, the people at greatest risk are the very young (whose immune systems have not been previously exposed to the virus) and the very old, who lack the physical resilience to withstand the assault by the disease. Most deaths are among these groups, leading to a “bathtub curve” of mortality. This outbreak was different: the young and elderly were largely spared, while those in the prime of life were struck down, with many dying quickly of symptoms which resembled pneumonia. Slowly the outbreak receded, and by mid-March things were returning to normal. (The location and mechanism where the disease originated remain controversial to this day and we may never know for sure. After weighing competing theories, the author believes the Kansas origin most likely, but other origins have their proponents.)

That would have been the end of it, had not soldiers from Camp Funston, the second largest Army camp in the U.S., with 56,000 troops, visited their families in Haskell County while on leave. They returned to camp carrying the disease. The spark had landed in the tinderbox. The disease spread outward as troop trains travelled between camps. Often a train would leave carrying healthy troops (infected but not yet symptomatic) and arrive with up to half the company sick and highly infectious to those at the destination. Before long the disease arrived via troop ships at camps and at the front in France.

This was just the first wave. The spring influenza was unusual in the age group it hit most severely, but was not particularly more deadly than typical annual outbreaks. Then in the fall a new form of the disease returned in a much more virulent form. It is theorised that under the chaotic conditions of wartime a mutant form of the virus had emerged and rapidly spread among the troops and then passed into the civilian population. The outbreak rapidly spread around the globe, and few regions escaped. It was particularly devastating to aboriginal populations in remote regions like the Arctic and Pacific islands who had not developed any immunity to influenza.

The pathogen in the second wave could kill directly within a day by destroying the lining of the lung and effectively suffocating the patient. The disease was so virulent and aggressive that some medical researchers doubted it was influenza at all and suspected some new kind of plague. Even those who recovered from the disease had much of their immunity and defences against respiratory infection so impaired that some people who felt well enough to return to work would quickly come down with a secondary infection of bacterial pneumonia which could kill them.

All of the resources of the new scientific medicine were thrown into the battle with the disease, with little or no impact upon its progression. The cause of influenza was not known at the time: some thought it was a bacterial disease while others suspected a virus. Further adding to the confusion is that influenza patients often had a secondary infection of bacterial pneumonia, and the organism which causes that disease was mis-identified as the pathogen responsible for influenza. Heroic efforts were made, but the state of medical science in 1918 was simply not up to the challenge posed by influenza.

A century later, influenza continues to defeat every attempt to prevent or cure it, and another global pandemic remains a distinct possibility. Supportive treatment in the developed world and the availability of antibiotics to prevent secondary infection by pneumonia will reduce the death toll, but a mass outbreak of the virus on the scale of 1918 would quickly swamp all available medical facilities and bring society to the brink as it did then. Even regular influenza kills between a quarter and a half million people a year. The emergence of a killer strain like that of 1918 could increase this number by a factor of ten or twenty.

Influenza is such a formidable opponent due to its structure. It is an RNA virus which, unusually for a virus, has not a single strand of genetic material but seven or eight separate strands of RNA. Some researchers argue that in an organism infected with two or more variants of the virus these strands can mix to form new mutants, allowing the virus to mutate much faster than other viruses with a single strand of genetic material (this is controversial). The virus particle is surrounded by proteins called hemagglutinin (HA) and neuraminidase (NA). HA allows the virus to break into a target cell, while NA allows viruses replicated within the cell to escape to infect others.

What makes creating a vaccine for influenza so difficult is that these HA and NA proteins are what the body's immune system uses to identify the virus as an invader and kill it. But HA and NA come in a number of variants, and a specific strain of influenza may contain one from column H and one from column N, creating a large number of possibilities. For example, H1N2 is endemic in birds, pigs, and humans. H5N1 caused the bird flu outbreak in 2004, and H1N1 was responsible for the 1918 pandemic. It gets worse. As a child, when you are first exposed to influenza, your immune system will produce antibodies which identify and target the variant to which you were first exposed. If you were infected with and recovered from, say, H3N2, you'll be pretty well protected against it. But if, subsequently, you encounter H1N1, your immune system will recognise it sufficiently to crank out antibodies, but they will be coded to attack H3N2, not the H1N1 you're battling, against which they're useless. Influenza is thus a chameleon, constantly changing its colours to hide from the immune system.

Strains of influenza tend to come in waves, with one HxNy variant dominating for some number of years, then shifting to another. Developers of vaccines must play a guessing game about which you're likely to encounter in a given year. This explains why the 1918 pandemic particularly hit healthy adults. Over the decades preceding the 1918 outbreak, the primary variant had shifted from H1N1, then decades of another variant, and then after 1900 H1N1 came back to the fore. Consequently, when the deadly strain of H1N1 appeared in the fall of 1918, the immune systems of both young and elderly people were ready for it and protected them, but those in between had immune systems which, when confronted with H1N1, produced antibodies for the other variant, leaving them vulnerable.

With no medical defence against or cure for influenza even today, the only effective response in the case of an outbreak of a killer strain is public health measures such as isolation and quarantine. Influenza is airborne and highly infectious: the gauze face masks you see in pictures from 1918 were almost completely ineffective. The government response to the outbreak in 1918 could hardly have been worse. After creating military camps which were nothing less than a culture medium containing those in the most vulnerable age range packed in close proximity, once the disease broke out and reports began to arrive that this was something new and extremely lethal, the troop trains and ships continued to run due to orders from the top that more and more men had to be fed into the meat grinder that was the Western Front. This inoculated camp after camp. Then, when the disease jumped into the civilian population and began to devastate cities adjacent to military facilities such as Boston and Philadelphia, the press censors of Wilson's proto-fascist war machine decided that honest reporting of the extent and severity of the disease or measures aimed at slowing its spread would impact “morale” and war production, so newspapers were ordered to either ignore it or print useless happy talk which only accelerated the epidemic. The result was that in the hardest-hit cities, residents confronted with the reality before their eyes giving to lie to the propaganda they were hearing from authorities retreated into fear and withdrawal, allowing neighbours to starve rather than risk infection by bringing them food.

As was known in antiquity, the only defence against an infectious disease with no known medical intervention is quarantine. In Western Samoa, the disease arrived in September 1918 on a German steamer. By the time the disease ran its course, 22% of the population of the islands was dead. Just a few kilometres across the ocean in American Samoa, authorities imposed a rigid quarantine and not a single person died of influenza.

We will never know the worldwide extent of the 1918 pandemic. Many of the hardest-hit areas, such as China and India, did not have the infrastructure to collect epidemiological data and what they had collapsed under the impact of the crisis. Estimates are that on the order of 500 million people worldwide were infected and that between 50 and 100 million died: three to five percent of the world's population.

Researchers do not know why the 1918 second wave pathogen was so lethal. The genome has been sequenced and nothing jumps out from it as an obvious cause. Understanding its virulence may require recreating the monster and experimenting with it in animal models. Obviously, this is not something which should be undertaken without serious deliberation beforehand and extreme precautions, but it may be the only way to gain the knowledge needed to treat those infected should a similar wild strain emerge in the future. (It is possible this work may have been done but not published because it could provide a roadmap for malefactors bent on creating a synthetic plague. If this be the case, we'll probably never know about it.)

Although medicine has made enormous strides in the last century, influenza, which defeated the world's best minds in 1918, remains a risk, and in a world with global air travel moving millions between dense population centres, an outbreak today would be even harder to contain. Let us hope that in that dire circumstance authorities will have the wisdom and courage to take the kind of dramatic action which can make the difference between a regional tragedy and a global cataclysm.

Posted at 21:34 Permalink

Friday, October 3, 2014

Reading List: The Box

Levinson, Marc. The Box. Princeton: Princeton University Press, [2006] 2008. ISBN 978-0-691-13640-0.
When we think of developments in science and technology which reshape the world economy, we often concentrate upon those which build on fundamental breakthroughs in our understanding of the world we live in, or technologies which employ them to do things never imagined. Examples of these are electricity and magnetism, which gave us the telegraph, electric power, the telephone, and wireless communication. Semiconductor technology, the foundation of the computer and Internet revolutions, is grounded in quantum mechanics, elaborated only in the early 20th century. The global positioning satellites which you use to get directions when you're driving or walking wouldn't work if they did not compensate for the effects of special and general relativity upon the rate at which clocks tick in moving objects and those in gravitational fields.

But sometimes a revolutionary technology doesn't require a scientific breakthrough, nor a complicated manufacturing process to build, but just the realisation that people have been looking at a problem all wrong, or have been earnestly toiling away trying to solve some problem other than the one which people are ready to pay vast sums of money to have solved, once the solution is placed on the market.

The cargo shipping container may be, physically, the one of the least impressive technological achievements of the 20th century, right up there with the inanimate carbon rod, as it required no special materials, fabrication technologies, or design tools which did not exist a century before, and yet its widespread adoption in the latter half of the 20th century was fundamental to the restructuring of the global economy which we now call “globalisation”, and changed assumptions about the relationship between capital, natural resources, labour, and markets which had existed since the start of the industrial revolution.

Ever since the start of ocean commerce, ships handled cargo in much the same way. The cargo was brought to the dock (often after waiting for an extended period in a dockside warehouse for the ship to arrive), then stevedores (or longshoremen, or dockers) would load the cargo into nets, or onto pallets hoisted by nets into the hold of the ship, where other stevedores would unload it and stow the individual items, which might consist of items as varied as bags of coffee beans, boxes containing manufactured goods, barrels of wine or oil, and preserved food items such as salted fish or meat. These individual items were stored based upon the expertise of the gangs working the ship to make the most of the irregular space of the ship's cargo hold, and if the ship was to call upon multiple ports, in an order so cargo could be unloaded with minimal shifting of that bound for subsequent destinations on the voyage. Upon arrival at a port, this process was reversed to offload cargo bound there, and then the loading began again. It was not unusual for a cargo ship to spend 6 days or more in each port, unloading and loading, before the next leg on its voyage.

Shipping is both capital- and labour-intensive. The ship has to be financed and incurs largely fixed maintenance costs, and the crew must be paid regardless of whether they're at sea or waiting in port for cargo to be unloaded and loaded. This means that what engineers call the “duty cycle” of the ship is critical to its cost of operation and, consequently, what the shipowner must charge shippers to make a profit. A ship operating coastal routes in the U.S., say between New York and a port in the Gulf, could easily spend half its time in ports, running up costs but generating no revenue. This model of ocean transport, called break bulk cargo, prevailed from the age of sail until the 1970s.

Under the break bulk model, ocean transport was very expensive. Further, with cargos sitting in warehouses waiting for ships to arrive on erratic schedules, delivery times were not just long but also unpredictable. Goods shipped from a factory in the U.S. midwest to a destination in Europe would routinely take three months to arrive end to end, with an uncertainty measured in weeks, accounting for trucking, railroads, and ocean shipping involved in getting them to their destination. This meant that any importation of time-sensitive goods required keeping a large local inventory to compensate for unpredictable delivery times, and paying the substantial shipping cost included in their price. Economists, going back to Ricardo, often modelled shipping as free, but it was nothing of the kind, and was often the dominant factor in the location and structure of firms.

When shipping is expensive, firms have an advantage in being located in proximity to both their raw materials (or component suppliers) and customers. Detroit became the Motor City in large part because its bulk inputs: iron ore and coal, could be transported at low cost from mines to factories by ships plying the Great Lakes. Industries dependent on imports and exports would tend to cluster around major ports, since otherwise the cost of transporting their inputs and outputs overland from the nearest port would be prohibitive. And many companies simply concentrated on their local market, where transportation costs were not a major consideration in their cost structure. In 1964, when break bulk shipping was the norm, 40% of exports from Britain originated within 25 miles of their port of export, and two thirds of all imports were delivered to destinations a similar distance from their port of arrival.

But all of this was based upon the cost structure of break bulk ocean cargo shipping, and a similarly archaic way of handling rail and truck cargo. A manufacturing plant in Iowa might pack its goods destined for a customer in Belgium into boxes which were loaded onto a truck, driven to a terminal in Chicago where they were unloaded and reloaded into a boxcar, then sent by train to New Jersey, where they were unloaded and put onto a small ship to take them to the port of New York, where after sitting in a warehouse they'd be put onto a ship bound for a port in Germany. After arrival, they'd be transported by train, then trucked to the destination. Three months or so later, plus or minus a few, the cargo would arrive—at least that which wasn't stolen en route.

These long delays, and the uncertainty in delivery times, required those engaging in international commerce to maintain large inventories, which further increased the cost of doing business overseas. Many firms opted for vertical integration in their own local region.

Malcom McLean started his trucking company in 1934 with one truck and one driver, himself. What he lacked in capital (he often struggled to pay bridge tolls when delivering to New York), he made up in ambition, and by 1945, his company operated 162 trucks. He was a relentless cost-cutter, and from his own experience waiting for hours on New York docks for his cargo to be unloaded onto ships, in 1953 asked why shippers couldn't simply put the entire truck trailer on a ship rather than unload its cargo into the ship's hold, then unload it piece by piece at the destination harbour and load it back onto another truck. War surplus Liberty ships were available for almost nothing, and they could carry cargo between the U.S. northeast and south at a fraction of the cost of trucks, especially in the era before expressways.

McLean immediately found himself in a tangled web of regulatory and union constraints. Shipping, trucking, and railroads were all considered completely different businesses, each of which had accreted its own, often bizarre, government regulation and union work rules. The rate a carrier could charge for hauling a ton of cargo from point A to point B depended not upon its mass or volume, but what it was, with radically different rates for say, coal as opposed to manufactured goods. McLean's genius was in seeing past all of this obstructionist clutter and realising that what the customer—the shipper—wanted was not to purchase trucking, railroad, and shipping services, but rather delivery of the shipment, however accomplished, at a specified time and cost.

The regulatory mess made it almost impossible for a trucking company to own ships, so McLean created a legal structure which would allow his company to acquire a shipping line which had fallen on hard times. He then proceeded to convert a ship to carry containers, which would not be opened from the time they were loaded on trucks at the shipper's location until they arrived at the destination, and could be transferred between trucks and ships rapidly. Working out the details of the construction of the containers, setting their size, and shepherding all of this through a regulatory gauntlet which had never heard of such concepts was daunting, but the potential payoff was enormous. Loading break bulk cargo onto a ship the size of McLean's first container vessel cost US$ 5.83 per ton. Loading freight in containers cost US$ 0.16 per ton. This reduction in cost, passed on to the shipper, made containerised freight compelling, and sparked a transformation in the global economy.

Consider Barbie. Her body is manufactured in China, using machines from Japan and Europe and moulds designed in the U.S. Her hair comes from Japan, the plastic for her body from Taiwan, dyed with U.S. pigments, and her clothes are produced in other factories in China. The final product is shipped worldwide. There are no large inventories anywhere in the supply chain: every step depends upon reliable delivery of containers of intermediate products. Managers setting up such a supply chain no longer care whether the products are transported by truck, rail, or sea, and since transportation costs for containers are so small compared to the value of their contents (and trade barriers such as customs duties have fallen), the location of suppliers and factories is based almost entirely upon cost, with proximity to resources and customers almost irrelevant. We think of the Internet as having abolished distance, but the humble ocean cargo container has done so for things as much as the Internet has for data.

This is a thoroughly researched and fascinating look at how the seemingly most humble technological innovation can have enormous consequences, and also how the greatest barriers to restructuring economies may be sclerotic government and government-enabled (union) structures which preserve obsolete models long after they have become destructive of prosperity. It also demonstrates how those who try to freeze innovation into a model fixed in the past will be bypassed by those willing to embrace a more efficient way of doing business. The container ports which handle most of the world's cargo are, for the most part, not the largest ports of the break bulk era. They are those which, unencumbered by history, were able to build the infrastructure required to shift containers at a rapid rate.

The Kindle edition has some flaws. In numerous places, spaces appear within words which don't belong there (perhaps words hyphenated across lines in the print edition and not re-joined?) and the index is just a list of searchable terms, not linked to references in the text.

Posted at 23:46 Permalink

Saturday, September 27, 2014

Reading List: Destination Moon

Byers, Bruce K. Destination Moon. Washington: National Aeronautics and Space Administration, 1977. NASA TM X-3487.
In the mid 1960s, the U.S. Apollo lunar landing program was at the peak of its budget commitment and technical development. The mission mode had already been chosen and development of the flight hardware was well underway, along with the ground infrastructure required to test and launch it and the global network required to track missions in flight. One nettlesome problem remained. The design of the lunar module made assumptions about the properties of the lunar surface upon which it would alight. If the landing zone had boulders which were too large, craters sufficiently deep and common that the landing legs could not avoid, or slopes too steep to avoid an upset on landing or tipping over afterward, lunar landing missions would all be aborted by the crew when they reached decision height, judging there was no place they could set down safely. Even if all the crews returned safely without having landed, this would be an ignominious end to the ambitions of Project Apollo.

What was needed in order to identify safe landing zones was high-resolution imagery of the Moon. The most capable Earth-based telescopes, operating through Earth's turbulent and often murky atmosphere, produced images which resolved objects at best a hundred times larger that those which could upset a lunar landing mission. What was required was a large area, high resolution mapping of the Moon and survey of potential landing zones, which could only be done, given the technology of the 1960s, by going there, taking pictures, and returning them to Earth. So was born the Lunar Orbiter program, which in 1966 and 1967 sent lightweight photographic reconnaissance satellites into lunar orbit, providing both the close-up imagery needed to select landing sites for the Apollo missions, but also mapping imagery which covered 99% of the near side of the Moon and 85% of the far side, In fact, Lunar Orbiter provided global imagery of the Moon far more complete than that which would be available for the Earth many years thereafter.

Accomplishing this goal with the technology of the 1960s was no small feat. Electronic imaging amounted to analogue television, which, at the altitude of a lunar orbit, wouldn't produce images any better than telescopes on Earth. The first spy satellites were struggling to return film from Earth orbit, and returning film from the Moon was completely impossible given the mass budget of the launchers available. After a fierce competition, NASA contracted with Boeing to build the Lunar Orbiter, designed to fit on NASA's workhorse Atlas-Agena launcher, which seriously constrained its mass. Boeing subcontracted with Kodak to build the imaging system and RCA for the communications hardware which would relay the images back to Earth and allow the spacecraft to be controlled from the ground.

The images were acquired by a process which may seem absurd to those accustomed to present-day digital technologies but which seemed miraculous in its day. In lunar orbit, the spacecraft would aim its cameras (it had two: a mapping camera which produced overlapping wide-angle views and a high-resolution camera that photographed clips of each frame with a resolution of about one metre) at the Moon and take a series of photos. Because the film used had a very low light sensitivity (ASA [now ISO] 1.6), on low-altitude imaging passes the film would have to be moved to compensate for the motion of the spacecraft to avoid blurring. (The low light sensitivity of the film was due to its very high spatial resolution, but also reduced its likelihood of being fogged by exposure to cosmic rays or energetic particles from solar flares.)

After being exposed, the film would subsequently be processed on-board by putting it in contact with a band containing developer and fixer, and then the resulting negative would be read back for transmission to Earth by scanning it with a moving point of light, measuring the transmission through the negative, and sending the measured intensity back as an analogue signal. At the receiving station, that signal would be used to modulate the intensity of a spot of light scanned across film which, when developed and assembled into images from strips, revealed the details of the Moon. The incoming analogue signal was recorded on tape to provide a backup for the film recording process, but nothing was done with the tapes at the time. More about this later….

Five Lunar Orbiter missions were launched, and although some experienced problems, all achieved their primary mission objectives. The first three missions provided all of the data required by Apollo, so the final two could be dedicated to mapping the Moon from near-polar orbits. After the completion of their primary imaging missions, Lunar Orbiters continued to measure the radiation and micrometeoroid environment near the Moon, and contributed to understanding the Moon's gravitational field, which would be important in planning later Apollo missions that would fly in very low orbits around the Moon. On August 23rd, 1966, the first Lunar Orbiter took one of the most iconic pictures of the 20th century: Earthrise from the Moon. The problems experienced by Lunar Orbiter missions and the improvisation by ground controllers to work around them set the pattern for subsequent NASA robotic missions, with their versatile, reconfigurable flight hardware and fine-grained control from the ground.

You might think the story of Lunar Orbiter a footnote to space exploration history which has scrolled off the screen with subsequent Apollo lunar landings and high-resolution lunar mapping by missions such as Clementine and the Lunar Reconnaissance Orbiter, but that fails to take into account the exploits of 21st century space data archaeologists. Recall that I said that all of the image data from Lunar Orbiter missions was recorded on analogue tapes. These tapes contained about 10 bits of dynamic range, as opposed to the 8 bits which were preserved by the optical recording process used in receiving the images during the missions. This, combined with contemporary image processing techniques, makes for breathtaking images recorded almost half a century ago, but never seen before. Here are a document and video which record the exploits of the Lunar Orbiter Image Recovery Project (LOIRP). Please visit the LOIRP Web site for more restored images and details of the process of restoration.

Posted at 00:37 Permalink