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Who's Winning the Republican Race? Everybody!
Polls indicating that Republican voters prefer this or that candidate for president are often as simplistic as they are hard to avoid. Many observers complain that media coverage of the campaign is too focused on the “horse race.” In some ways, though, the coverage isn’t even as nuanced as that of a horse race, where horses are picked to win, but also to place or to show.
One way to get a clearer picture of an electorate’s preferences is to ask prospective voters to rank the candidates and not merely say which one is their first choice. Who is their second choice, third, fourth, fifth? Doing this allows us to get a better overall view of their appeal or lack thereof. It also makes clear that “Who’s ahead?” is not by any means a question with a single, simple answer.
Let’s imagine that likely Republican voters were asked to rank Herman Cain, Newt Gingrich, Ron Paul, Rick Perry, and Mitt Romney (Michele Bachmann, Jon Huntsman and Rick Santorum, please accept my apologies). This is for illustration only, although it’s not that far off the mark, so let’s further imagine:
that 36.3% of them favored Romney to Gingrich to Paul to Cain to Perry;
and 27.3% of them favored Cain to Paul to Gingrich to Perry to Romney;
and 18.2% of them favored Perry to Paul to Gingrich to Cain to Romney;
and 9.1% of them favored Gingrich to Perry to Cain to Paul to Romney;
and 9.1% of them favored Paul to Gingrich to Perry to Romney to Cain.
Romney is clearly preferred by the highest percentage of voters so using the conventional method of plurality, Romney, the most conventional candidate, is the clear leader.
But impressed that the second highest percentage of voters prefer him (“Wow! 27.3% is almost exactly the sum of my 9-9-9 plan”), Cain might well argue that a runoff between him and Romney is appropriate. In such a runoff, the numbers above suggest that Cain would win since 54.6% all of the voters polled ranked him higher than Romney.
Poring over the preference rankings, Perry supporters might warm instead to the idea of what’s often called an instant runoff (a version of which was just used in the San Francisco mayoral election). This differs from a standard runoff in that the candidates with the fewest first place votes (Gingrich and Paul in this case) are summarily eliminated. Next the ranking for the others are adjusted (Perry would gain another 18.2% of the first place votes once Gingrich and Paul are gone). Then the method dictates that the candidate among the remaining three having the fewest first place votes (Cain in this case) is eliminated and the ranking for the two remaining candidates adjusted. After this only Romney and Perry are left, and Perry beats Romney handily.
Scowling, Gingrich insists that we should pay more attention to the overall rankings, not just to the voters’ most preferred candidates. He says it’s only fair that first place votes should each be accorded 5 points, second place votes 4 points, third place 3 points, fourth 2 points, and last place votes 1 point. Using this method each candidate amasses points from the entire preference ranking, which Gingrich argues will more fairly measure that candidate’s support. Needless to add, Gingrich wins if this method is adopted.
Ever the individualist, Paul contends that only mano-a-mano contests should count and notes that given the preference rankings he beats each of the other candidates in a head-to-head race. If they were the only two candidates, more voters would prefer Paul to Romney. Likewise, more would prefer him to Gingrich, to Perry, and to Cain. His claim is true and underlies his argument that he deserves to be overall winner.
So who’s ahead? Given the preference ranking above, each of the five candidates has a reasonable case for being called the front-runner. The numbers were, of course, cherry-picked to yield these different outcomes, but real races often have many of these same oddities, which together provide a more nuanced feel for the relative strengths of the various candidates.
Some pollsters have already made an effort to get beyond the traditional “Who would you vote for if the election were held today?” Gallup, for example, has been experimenting this year with a “positive intensity score,” which is intended to measure the ability of candidates to arouse enthusiasm among those voters who know them. And, in cities such as St. Paul, Minn., Portland, Me., and San Francisco, where instant run-offs are employed, pollsters have expended effort and will inevitably expend more to determine how the voters rank the candidates. Private polling by the candidates themselves is often more sophisticated than the polls the public gets to read about.
Going further and compiling a full preference ranking of the candidates would, no doubt, be difficult and costly. Many voters don’t know all the candidates, others don’t rank them rationally, preferences don’t always hold, and so on.
Nevertheless, to the usual questions about voters’ top choices, pollsters should add questions about their second or third choices and about those candidates they’d refuse to vote for under any circumstances. Elephant and donkey races deserve at least as much analysis of possible outcomes as horse races get.
John Allen Paulos, a professor of mathematics at Temple University, is the author of eight books, including “Innumeracy” and “A Mathematician Reads the Newspaper.”
Saturday, November 12, 2011
Who's Winning the Republican Race? Everybody!
Report Details Chaos at Fukushima Daiichi After Quake
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Fukushima Daiichi Unit 1 was stuck in darkness, and everyone on site feared that the reactor core was damaged. It was the day after a huge earthquake and a towering tsunami devastated the plant, and the workers for Tokyo Electric Power Company knew they were the only hope for halting an unfolding nuclear disaster.
Another power company tried to help. It rushed a mobile electrical generator to the site to power the crucial water pumps that cool the reactor. But connecting it required pulling a thick electrical cable across about 650 feet of ground strewn with debris from the tsunami and made more treacherous by open holes left when manhole covers were washed away.
The cable, four inches in diameter, weighed approximately one ton, and 40 workers were needed to maneuver it into position. Their urgent efforts were interrupted by aftershocks and alarms about possible new tsunamis.
By 3:30 in the afternoon, the workers had managed what many consider a heroic feat: they had hooked up the cable. Six minutes later, a hydrogen explosion ripped through the reactor building, showering the area with radioactive debris and damaging the cable, rendering it useless.
Those details about the first hours after the earthquake at the stricken plant are part of a new 98-page chronology of the Fukushima accident. The account, compiled by American nuclear experts, is meant to form a basis for American nuclear operators and the Nuclear Regulatory Commission to learn lessons from the disaster. But it also provides a rare, detailed look at workers’ frantic efforts to save the plant, portraying (in measured technical language) scenes worthy of the most gripping disaster movies.
The experts who compiled the report work for the Institute of Nuclear Power Operations, an Atlanta organization that is an integral part of the American nuclear industry and one that has won praise over the years for its audits, sometimes critical, of plants around the country.
The authors could provide a deep level of detail because they were able to interview operators and executives from Tokyo Electric Power Company and had access to many of the company’s documents and data.
The chronology does not draw any conclusions about the accident, or analyze the actions taken after the earthquake; it is intended only to provide an agreed-upon set of facts for further study. In that way the document might be more useful for the nuclear industry than for Japanese citizens still hungry for assurances that they are no longer in danger and angry over missteps, documented in the news media, that led to more people being exposed to more radiation than was necessary.
One aspect of the disaster that American companies are likely to focus on is Fukushima’s troubles with its venting system, meant to reduce pressure and avert explosions when crucial cooling systems fail. Another focus is likely to be the extreme difficulty workers had in getting emergency equipment to the reactors where they were needed.
The report is likely to reinforce the conviction of American companies that operate reactors of the design used at Fukushima that venting from the containment vessels around reactors early in an accident is better than waiting, even though radioactive material will be released. The delays in Japan appear to have contributed to explosions that damaged the vessels and ultimately led to larger releases of contaminants.
It has been clear for months that Fukushima operators delayed venting for hours, even after the government ordered that the action be taken. The chronology, however, suggests for the first time that some delays were because plant executives believed that they were required to wait for evacuation of surrounding areas.
Because the chronology is based mainly on accounts by Tepco and its workers and company data, it is by nature limited. It does not, for example, relate that there was tension between Tepco and the government over when to vent, as the news media have reported.
The report is also likely to incite more debate about how emergency equipment and material are stored and what types of contingency plans need to be made to ensure equipment can reach reactors in a disaster. Nuclear critics in the United States have long complained that American emergency rules do not take into account that a natural phenomenon could cause an accident at a plant and make it hard to get help from outside.
For example, although the plant had three fire engines that could have pumped in vital cooling water, one was damaged in the tsunami and another was blocked by earthquake damage to roads. Inspections at some American reactors after the Japanese quake and tsunami found that they were storing emergency gear in a way that made it vulnerable to the emergency it was intended for.
The report was perhaps most vivid when it was describing workers’ often unsuccessful efforts to salvage the situation. In one case, plant workers are said to have broken through a security fence to take a fire truck to unit 1 so it could pump water to cool the reactor. (The plant’s cooling system by that time was unusable, and without it, reactors and fuel pools can overheat and cause meltdowns.)
But as often happened during the disaster, the workers’ struggles only partly paid off. Increasing heat caused the pressure inside the containment vessel to build. By the time the fire truck started pumping, workers were able to force in less than 10 gallons per minute, not much more than a kitchen faucet puts out. That was far too little to cool the nuclear fuel and reduce pressure.
The report also takes note of the human toll the disaster took on workers.
It points out that many plant workers had lost their homes and even their families in the tsunami, and that for days after the quake, they were sleeping on the floor at the plant, soaking up radiation doses even in the control room. Because of food shortages, they were provided with only a biscuit for breakfast and a bowl of noodles for dinner.
Working in darkness and without electricity, even simple tasks became challenging. At one point, control room operators formed themselves into teams of two, to dash into high-dose areas to try to open a crucial vent. One would hold the flashlight and monitor the radiation dose, while the other would try to get a valve to move. But there was no communication once the team was in the field, so the next team could leave for the reactor only after the first had returned.
Eventually, the radiation levels got too high, and they gave up. The first explosion rocked the plant soon after, belching clouds of radioactive materials and giving the world its clearest sense of the scope of the catastrophe unfolding in Japan.
Hiroko Tabuchi contributed reporting from Tokyo.
§
Thursday, November 03, 2011
24 Hours at Fukushima
24 Hours at Fukushima
A blow-by-blow account of the worst nuclear accident since Chernobyl
By
Eliza Strickland / November 2011
Photos: [Left] Christoph Bangert/ LaIF/Redux; [Right] TEPCO
RADIATION AND RUIN:
Click images to enlarge.
Editor's Note: This is part of the IEEE Spectrum special report:
Fukushima and the Future of Nuclear Power
.
Millions of people had to die on highways, for example, before governments forced auto companies to get serious about safety in the 1980s. But with nuclear power, learning by disaster has never really been an option. Or so it seemed, until officials found themselves grappling with the world's third major accident at a nuclear plant. On 11 March, a tidal wave set in motion a sequence of events that led to meltdowns in three reactors at the Fukushima Dai-ichi power station, 250 kilometers northeast of Tokyo.
Sometimes it takes a disaster
before we humans really figure out how to design something. In fact, sometimes it takes more than one.
Unlike the
Three Mile Island
accident in 1979 and
Chernobyl
in 1986, the chain of failures that led to disaster at Fukushima was caused by an extreme event. It was precisely the kind of occurrence that nuclear-plant designers strive to anticipate in their blueprints and emergency-response officials try to envision in their plans. The struggle to control the stricken plant, with its remarkable heroism, improvisational genius, and heartbreaking failure, will keep the experts busy for years to come. And in the end the calamity will undoubtedly improve nuclear plant design.
True, the antinuclear forces will find plenty in the Fukushima saga to bolster their arguments. The interlocked and cascading chain of mishaps seems to be a textbook validation of the "
normal accidents
" hypothesis developed by
Charles Perrow
after Three Mile Island. Perrow, a Yale University sociologist, identified the nuclear power plant as the canonical tightly coupled system, in which the occasional catastrophic failure is inevitable.
On the other hand, close study of the disaster's first 24 hours, before the cascade of failures carried reactor 1 beyond any hope of salvation, reveals clear inflection points where minor differences would have prevented events from spiraling out of control. Some of these are astonishingly simple: If the emergency generators had been installed on upper floors rather than in basements, for example, the disaster would have stopped before it began. And if workers had been able to vent gases in reactor 1 sooner, the rest of the plant's destruction might well have been averted.
The world's three major nuclear accidents had very different causes, but they have one important thing in common: In each case, the company or government agency in charge withheld critical information from the public. And in the absence of information, the panicked public began to associate all nuclear power with horror and radiation nightmares. The owner of the Fukushima plant, the
Tokyo Electric Power Co.
(TEPCO), has only made the situation worse by presenting the Japanese and global public with obfuscations instead of a clear-eyed accounting.
Citing a government investigation, TEPCO has steadfastly refused to make workers available for interviews and is barely answering questions about the accident. By piecing together as best we can the story of what happened during the first 24 hours, when reactor 1 was spiraling toward catastrophe, we hope to facilitate the process of learning-by-disaster.
When the 9.0-magnitude earthquake
struck off the east coast of Japan, at 2:46 p.m. on 11 March, the ground beneath the power plant shook and alarms blared. In quivering control rooms, ceiling panels fell open and dust floated down onto instrument panels like snow. Within 5 seconds, control rods thrust upward into the three operational reactors and stopped the fission reactions. It was a flawless
automatic shutdown
, but the radioactive by-products in the reactors' fuel rods continued to generate tremendous amounts of heat.
Without adequate cooling, those rods would become hot enough to melt through the steel
pressure vessel
, and then through the steel containment vessel. That would result in the dreaded core-meltdown scenario, which could lead to the release of clouds of radioactivity that would be carried by winds to sicken or kill masses of people.
But the heat wouldn't be a problem so long as Fukushima Dai-ichi had power to run the pumps that circulate water from the reactor cores through heat-removal systems. The mighty earthquake had toppled power transmission towers and jumbled equipment at nearby substations, but the interruption in power to the plant was negligible: Within 10 seconds, the plant's emergency power system kicked in. Twelve diesel generators, most of them installed in basement areas below the turbines, were now responsible for the integrity of the plant's reactors—and the well-being of its workers.
At the time of the earthquake, three of the power station's six reactors were operating; the other three were down for scheduled maintenance. In the control rooms governing the active reactors—units 1, 2, and 3—the staff checked the cooling systems that remove residual heat from the reactor cores by cycling water through heat exchangers filled with seawater. Everything seemed under control. Water also filled the
THIS REPORT is based on interviews with officials from the Tokyo Electric Power Co. (TEPCO), Japan's Nuclear and Industrial Safety Agency, the U.S. Nuclear Regulatory Commission, the International Atomic Energy Agency, local governments, and with other experts in nuclear engineering, as well as a review of hundreds of pages of official reports.
spent-fuel pools
on the top floors of all six reactor buildings to prevent the pools from overheating.
At 2:52 p.m., the shift supervisor overseeing the plant's oldest reactor, the 40-year-old unit 1, confirmed that a backup cooling system called an isolation condenser (IC) had started up automatically. This system didn't need electric power to cycle steam through a cold-water tank on a higher floor, or to let the resulting water drop back down to the pressure vessel. But operators soon noticed that the IC was cooling the core too quickly, which could stress the steel walls of the pressure vessel. So they shut the system down. It was a by-the-book decision, but the book wasn't written for the extraordinary events of 11 March.
Tsunami alerts
flashed on TV screens, predicting a 3-meter-high tsunami for Fukushima prefecture. Although the coastal Fukushima Dai-ichi plant was 10 meters above sea level, nonessential personnel followed procedure and began evacuating the site.
At 3:27 p.m. the first tsunami wave surged into the man-made harbor protecting Fukushima Dai-ichi, rushing past a tidal gauge that measured a water height of 4 meters above normal. At 3:35 another set of much higher waves rolled in and obliterated the gauge. The water rushed over the seawalls and swept toward the plant. It smashed into the seawater pumps used in the heat-removal systems, then burst open the large doors on the turbine buildings and submerged power panels that controlled the operation of pumps, valves, and other equipment. Weeks later, TEPCO employees would measure the water stains on the buildings and estimate the monstrous tsunami's height at 14 meters.
In the basements of turbine and reactor buildings, 6 of the 12 diesel generators shuddered to a halt as the floodwaters inundated them. Five other generators cut out when their power distribution panels were drenched. Only one generator, on the first floor of a building near unit 6, kept going; unlike the others, all of its equipment was above the water line. Reactor 6 and its sister unit, reactor 5, would weather the crisis without serious damage, thanks in part to that generator.
The rest of Fukushima Dai-ichi now faced a cataclysmic scenario that nuclear power plant operators have long feared but never experienced: a complete station blackout.
Click on image for the full graphic view.
In the control room
where operators managed reactor 1, the alarms went silent. The overhead lights blinked off, and the indicator lights on the instrument panels faded away. The floodwaters had even knocked out the control room's batteries, the power source of last resort. The operators would have to respond to the emergency without working instruments.
With the power out, the pumps were no longer channeling water from unit 1's pressure vessel through the cooling system's heat exchangers, and the ferociously hot fuel rods were boiling the water into steam. The water level in the nuclear core was dropping, but, lacking power for their instruments, the plant operators could only guess at how fast the water was boiling away.
The isolation condenser, which relied on convection and gravity to perform its cooling function, should have helped keep the water level high in unit 1's core through the crisis. But operators had turned off the system just before the tsunami by closing its valves—and there was no electric power to reopen them and let steam and water flow. Workers struggled to manually open the valves on the IC system, but experts believe the IC provided no help after the tsunami struck.Emergency generators should be installed
LESSON 1
at high elevations or in watertight chambers.
As the operators surveyed the damage, they quickly realized that the diesel generators couldn't be salvaged and that external power wouldn't be restored anytime soon. In the plant's parking lots, workers raised car hoods, grabbed the batteries, and lugged them back to the control rooms. They found cables in storage rooms and studied diagrams. If they could connect the batteries to the instrument panels, they could at least determine the water levels in the pressure vessels.
TEPCO did have a backup for the emergency generators: power supply trucks outfitted with high-voltage dynamos. That afternoon, emergency managers at TEPCO's Tokyo headquarters sent 11 power supply trucks racing toward Fukushima Dai-ichi, 250 km away. They promptly got stuck in traffic. The roads that hadn't been damaged by the earthquake or tsunami were clogged with residents fleeing the disaster sites.
LESSON 2
If a cooling system is intended
to operate without power, make sure all of its parts can be manipulated without power.
At 4:36 p.m., TEPCO officially informed the Japanese government about the increasingly dire situation at reactor 1. The company declared that it "could not confirm" that any water was being injected into the reactor's core. The situation was better at the slightly more modern reactors 2 and 3, where emergency cooling systems were operating, driven by the steam from the reactors themselves. And the idled reactors 4, 5, and 6 didn't pose an immediate threat.
At 5:41, the sun set over the pools of seawater and the mounds of debris scattered around the power station. Work crews picked their way through the gloom by flashlight.
At around 9 p.m., operators finally plugged the car batteries they'd collected into the instrument panels and got a vital piece of information—the water level in reactor 1. The information seemed reassuring. The gauge registered a water level of 550 millimeters above the top of the fuel assembly, which, while far below normal safety standards, was enough to assure the operators that no fuel had melted yet.
But TEPCO's later analysis found that the gauges were wrong. Months later, calculations would show that the superheated water inside the reactor 1 pressure vessel had dropped all the way below the bottom of the uranium fuel rods shortly before operators checked the gauge, leaving the reactor core completely uncovered. Heat pulsed through the exposed rods. When temperatures passed 1300 °C, the fuel rods' protective zirconium cladding began to react with the steam inside the vessel, producing highly volatile
hydrogen gas
. And the uranium inside the fuel rods began to melt, slump, and sag.
Photo: Gamma/Getty Images
The Damage:
In the days following the tsunami, explosions tore the roofs off reactors 1, 3, and 4, and an interior detonation is thought to have damaged reactor 2.
Click to enlarge.
Throughout the night
of 11 March, radiation levels rose around the plant. At 9:51 p.m. managers prohibited entry into the unit 1 reactor building.
It was a wise decision, because in the bowels of the reactor, the meltdown had already begun. In the reactors used at Fukushima, the control rods thrust up into the pressure vessel from below, and the housings around each control rod's entry point were essentially weak spots. When the melted fuel began to pool at the bottom of the pressure vessel, it likely melted through those vulnerable seams. TEPCO's later analysis found that the pressure vessel was damaged by 11 p.m., allowing highly radioactive water and gases to leak into the primary containment vessel.
The containment vessel, which surrounds the pressure vessel, is a crucial line of defense: It's a thick steel hull meant to hold in any tainted materials that have escaped from the inner vessel. At 11:50 p.m. operators in the control room finally connected car batteries to the pressure gauge for the primary containment vessel. But the gauge revealed that the containment vessel had already exceeded its maximum operating pressure, increasing the likelihood that it would leak, crack, or even explode.Keep power trucks on or very close to the power plant site.
LESSON 3
As 11 March turned into 12 March, TEPCO headquarters told the sleepless operators that they must bring down the pressure by venting the containment vessel. A venting operation would jet the vessel's radioactive gases into the air; Fukushima Dai-ichi's nightmare would soon spread across the countryside.
That night, the desperate struggle to contain the peril at reactor 1 diverged into three responses. Besides the team making preparations to vent the containment vessel, there was also a group getting ready to receive the power supply trucks, which were still making their way to the plant. On arrival, they would supply electricity to restart the pumps and reestablish steady water circulation through the pressure vessel. The third team focused on another, short-term plan for cooling the core: fire trucks, which could inject water from emergency tanks into one of the reactor's cooling systems.
It was after midnight when the first power supply trucks began to arrive at the site, creeping along cracked roads. The trucks parked outside the unit 2 turbine building, adjacent to the troubled unit 1, where workers had found one undamaged power control panel. In the darkness, they began snaking a 200-meter-long power cable through the mud-caked building in order to connect it to the power control panel. Usually trucks are used to lay such a cable, which weighed more than a ton, but that night 40 workers did the job by hand. It took them 5 hours.
Work continued at the power control panel all morning and into the afternoon of 12 March. Finally, at 3:30 p.m., everything was ready. Current flowed from a power supply truck through the cable to the panel, which was ready to switch on the pumps for a backup cooling system inside the reactor 1 building. Workers prepared to start the flow of freshwater into the pressure vessel, knowing that they were about to take a crucial step toward stabilizing the plant.
Meanwhile, the fire engine team had been grappling with difficult logistics all through the early morning hours. Of the three fire engines on site, one had been wrecked by the tsunami; another was stuck near reactors 5 and 6, trapped by damaged roads. That left one fire engine to cool the overheating reactor 1. This truck was the best hope for getting water into the pressure vessel quickly, but it took hours to maneuver it through the plant's wreckage. Finally the workers smashed a lock on an electronic gate and drove the fire engine through.
In their initial, improvised response, the fire crew pumped water into the truck's storage tanks, then drove close to the side of the reactor building and injected the water into the fire protection system's intake lines. It was 5:46 a.m. on 12 March when the first drops of water sprayed across the molten fuel. Then the workers drove back to the water tanks and began the slow, arduous operation all over again. Eventually workers managed to use the fire engine's hoses to connect the water tanks directly to the intake lines and established a steady flow of water. By midafternoon, they had injected 80 000 liters of water into the pressure vessel using this makeshift system. But it was too little, too late.
LESSON 4
Install independent and secure battery systems to power crucial instruments during emergencies.
At 2:54 p.m., with freshwater supplies running short, TEPCO headquarters ordered the fire truck crews to inject seawater into the pressure vessel through the fire protection line. Under normal conditions, saltwater is never allowed in a reactor pressure vessel because it would corrode the vessel's protective steel walls and leave a mineral residue on the fuel rods. The decision was an admission that saving the reactor was no longer an option and that operators could only hope to prevent a wide-scale disaster. Fukushima Dai-ichi was now beyond the point of no return.
Workers stretched long fire hoses from a seaside pit that had been filled with seawater by the tsunami; three newly arrived fire engines lined up to pump the water through. They connected the hose to the fire protection system's intake line, and around 3:30 on 12 March they prepared to blast the reactor with seawater.
It had been 24 hours since the tsunami roared into the harbor, and the desperate efforts of both the power crew and the fire truck crew were about to pay off. It must have seemed that their exhaustion and terror were nearly at an end.
The order to vent
the containment vessel had come at midnight. But without power to remotely operate the vent system's valves, it wouldn't be a simple task.
And whether the workers knew it or not, time was of the essence. While the venting team prepared for action during the early morning hours of 12 March, gases were building up inside the primary containment vessel and pushing on its weakest points, its gaskets and seals, and they were starting to give. Hydrogen gas hissed through the breaches and drifted up to the top of the building. Hour by hour, the gas collected there until it formed a layer of pure combustible menace.
The workers in charge of the venting operation tookEnsure that catalytic hydrogen recombiners (power-free devices that turn dangerous hydrogen gas back into steam) are positioned at the tops of reactor buildings where gas would most likely collect.
LESSON 5
iodine tablets
. It was a feeble attempt at protection against the radiation they'd soon encounter, but it was better than nothing. They gathered protective head-to-toe suits and face masks connected to air tanks. At 3:45 a.m., the vent crew tried to measure the radiation dose inside the reactor building, which had been off limits for 6 hours. Armed with handheld dosimeters, they opened the air lock, only to find a malevolent white cloud of some "gaseous substance" billowing toward them. Fearing a radiation steam bath, they slammed the door shut. They didn't get their reading, but they had a good indication that things had already gone seriously wrong inside the reactor.
If they could have looked inside the reactor pressure vessel at around 6:30 a.m. on the morning of 12 March, they would have seen a nuclear core transformed into molten sludge. The melted mixture of uranium, zirconium, and other metals had oozed to the bottom of the reactor pressure vessel, where it was gradually eating through the steel floor.
But as the morning ticked on, the vent crew were forced to sit and wait; they were standing by for word that residents had been evacuated and that it was safe to release the radioactive gases into the air. The government had issued an evacuation order for residents living within 3 km the night before; in the early morning hours officials announced that everyone within a 10 km radius of the plant should pack up and go. Residents who had lived their whole lives in the shadow of the Fukushima Dai-ichi plant boarded buses, expecting to be gone for a couple of days at most.
At 9:03 a.m. the message came: The last buses had departed. At 9:04 workers set out for the reactor building to open the valves that would allow gas to flow out of the primary containment vessel. They entered the reactor building and began a long, dark trek around the periphery of the primary containment vessel, guided only by flashlight beams. As they walked, their handheld dosimeters flashed troubling numbers. In normal conditions, a nuclear plant employee's radiation limit is 50
millisieverts
per year; in an emergency situation it is 100 mSv. The workers had covered about half the distance to the valve when they realized they had to turn back—if they continued, they would exceed the 100 mSv dose. They returned to the control room at 9:30. They had failed.
Over the next hours the operators scrambled to find another way to open the valves; finally they decided to blast the valve open with air. They used a crane truck to haul a portable air compressor, the kind typically used at construction sites, to the crucial valve's location. At 2:00 p.m. the vent crew switched the compressor on, while workers in the control room nervously watched the gauge.
By 3:30 p.m. on 12 March, it seemed that the venting had worked and that the worst was over. The pressure had dropped significantly in unit 1's primary containment vessel, suggesting that the valve had opened and that gases had rushed through the pipes to the ventilation stack near the reactor building. The workers must have felt that the danger was ebbing. They had no idea that leaks from the vent lines had added even more hydrogen to the gas collected below the ceiling of unit 1's outer building—and it was now ready to blow.
At 3:36 p.m., a spark
flashed in the darkness of the reactor building, and hydrogen gas ignited. With a roar, the top of the reactor building exploded.
The roof shattered and the walls splintered; fragments of the building flew through the air. Chunks of rubble cut into the cable leading from the power truck, and the flow of current stopped; now the pumps could not be turned on, and freshwater could not cascade into the core. Other pieces of debris sliced into the fire engine hoses leading from the seawater pit. Smoke billowed upward, radiation levels soared, and the workers fled Fukushima's first radioactive ruin. It wouldn't be the last: The battle to contain the catastrophe during the first 24 hours was lost, and the explosions would keep coming.
The failure of reactor 1 made efforts to stabilize the other reactors exponentially more difficult: Now workers would be laboring in a radioactive hot zone littered with debris. In addition, when work crews returned to the power truck sometime after the explosion, they couldn't get the power flowing. So the disaster continued. At reactors 2 and 3, emergency cooling systems functioned for several days. When reactor 3's overtaxed system failed on 13 March, workers struggled to connect alternate water supplies and to vent the primary containment vessel. But work was slow, and soon reactor 3 followed reactor 1's example. Leaking gas collected at the top of the building, and itInstall power-free filters on vent lines to remove radio-active materials and allow for venting that won't harm nearby residents.
LESSON 6
exploded on the morning of 14 March
.
That blast further impeded recovery efforts at reactor 2, and on the morning of 15 March some
still-obscure explosive noise
resonated inside the unit 2 reactor building. On that same day, an explosion tore the roof off reactor building 4 and a fire broke out inside. TEPCO reports say the problems in reactor 4 were probably due to hydrogen gas that leaked in from reactor 3; despite early reports to the contrary, the spent fuel rods stored in pools in reactors 4, 5, and 6 were covered with water throughout the accident and never posed a threat.
Each detonation made the effort to stabilize the plant more hopeless. It is clear that if workers had been able to gain control of reactor 1, the whole terrible sequence of events would have been different. But could the workers have done anything differently to speed up their response? Could the full scope of the catastrophe have been averted? So far, TEPCO management hasn't answered those questions.
We've learned a great deal about the Fukushima accident in the past seven months. But the nuclear industry's trial-and-error learning process is a dreadful thing: The rare catastrophes advance the science of nuclear power but also destroy lives and render entire towns uninhabitable. Three Mile Island left the public terrified of nuclear power; Chernobyl scattered fallout across vast swaths of Eastern Europe and is estimated to have caused thousands of cancer deaths. So far, the cost of Fukushima is a dozen dead towns ringing the broken power station, more than 80 000 refugees, and a traumatized Japan. We will learn even more as TEPCO releases more details of what went wrong in the first days of the accident. But as we go forward, we will also live with the knowledge that some future catastrophe will have yet more lessons to teach us.
Friday, October 28, 2011
Geoffrey West on complexity
Geoffrey West on complexity
As I was sitting down after dinner this evening news came through the interwebs that Steve Jobs had passed away. Given that he had lived seven years with a form of pancreatic cancer, it’s pretty amazing he made it this far. As cantankerous as he was – and whether you love or hate Apple products – you can’t deny that he changed the world of personal electronics. He was a true visionary.
Anyway, on to other matters. At the recent FQXi conference on time I had the pleasure of sharing a Zodiac with Geoffrey West while bouncing around Åbyfjorden, Sweden (the patch under my ear in the picture below is what kept me from vomiting all over Geoffrey). Anyhow, he gave what I think was my favorite talk at the conference. I’ve linked to it below the picture (and note that if you catch site of me around 34 minutes or so, I am not sleeping!). It is worth a watch. In fact I think it ought to be required watching for just about anyone. It’s solidified my intention to start doing more research in complexity theory. I think physics provides the perfect means by which complexity can be studied, meaning that its reductionist methods tend to be ideal for solving complex problems – take it apart and put it back together again, piece by piece. Anyway, watch the video.
Here’s the video:
Superlinear Cities--Geoffrey West
Why cities grow and companies die
Superlinear Cities--Geoffrey West
"It's hard to kill a city," West began, "but easy to kill a company." The mean life of companies is 10 years. Cities routinely survive even nuclear bombs. And "cities are the crucible of civilization." They are the major source of innovation and wealth creation. Currently they are growing exponentially. "Every week from now until 2050, one million new people are being added to our cities."
"We need," West said, "a grand unified theory of sustainability--- a coarse-grained quantitative, predictive theory of cities."
Such a theory already exists in biology, and you can build on that. Working with macroecologist James Brown and others, West explored the fact that living systems such as individual organisms show a shocking consistency of scalability. (The theory they elucidated has long been known in biology as Kleiber's Law.) Animals, for example, range in size over ten orders of magnitude from a shrew to a blue whale. If you plot their metabolic rate against their mass on a log-log graph, you get an absolutely straight line. From mouse to human to elephant, each increase in size requires a proportional increase in energy to maintain it.
But the proportion is not linear. Quadrupling in size does not require a quadrupling in energy use. Only a tripling in energy use is needed. It's sublinear; the ratio is 3/4 instead of 4/4. Humans enjoy an economy of scale over mice, as elephants do over us.
With each increase in animal size there is a slowing of the pace of life. A shrew's heart beats 1,000 times a minute, a human's 70 times, and an elephant heart beats only 28 times a minute. The lifespans are proportional; shrew life is intense but brief, elephant life long and contemplative. Each animal, independent of size, gets about a billion heartbeats per life. (West added that human bodies run on 100 watts---2,000 calories of food a day. But our civilizational energy use adds up 11,000 watts per person. We're like blue whales walking around.)
Does such scalability apply to cities? If you plot, say, the number of gas stations against the size of population of metropolitan areas on a log-log scale, it turns out you get another straight line. Ditto with the length of electrical lines, carbon footprint, etc. Per capita, big city dwellers use less energy than small town dwellers. As with animals, there is greater efficiency with size, this time at a 9/10 ratio. Energy use is sublinear.
But unlike animals, cities do not slow down as they get bigger. They speed up with size! The bigger the city, the faster people walk and the faster they innovate. All the productivity-related numbers increase with size---wages, patents, colleges, crimes, AIDS cases---and their ratio is superlinear. It's 1.15/1. With each increase in size, cities get a value-added of 15 percent. Agglomerating people, evidently, increases their efficiency and productivity.
Does that go on forever? Cities create problems as they grow, but they create solutions to those problems even faster, so their growth and potential lifespan is in theory unbounded.
(West pointed out that there is a bit of variability between cities worth noticing. On the plot of crimes/population, Tokyo has slightly fewer crimes for its size, and Osaka has slightly more. In the U.S., the most patents per capita come from Corvalis, Oregon, and the least from Abiline, Texas. Such variations tend to remain constant over decades, despite everyone's efforts to adjust them. "Exciting cities stay exciting, and boring cities stay boring.")
Are corporations more like animals or more like cities? They want to be like cities, with ever increasing productivity as they grow and potentially unbounded lifespans. Unfortunately, West et al.'s research on 22,000 companies shows that as they increase in size from 100 to 1,000,000 employees, their net income and assets (and 23 other metrics) per person increase only at a 4/5 ratio. Like animals and cities they do grow more efficient with size, but unlike cities, their innovation cannot keep pace as their systems gradually decay, requiring ever more costly repair until a fluctuation sinks them. Like animals, companies are sublinear and doomed to die.
What is the actual mechanism of difference? Research on that continues. "Cities tolerate crazy people," West observed, "Companies don't."
-- by Stewart Brand
Tuesday, October 25, 2011
This is not a conspiracy...apparently
Revealed – the capitalist network that runs the world
Updated 13:15 24 October 2011 by Andy Coghlan and Debora MacKenzie
Magazine issue 2835. Subscribe and save
For similar stories, visit the Finance and Economics Topic Guide
AS PROTESTS against financial power sweep the world this week, science may have confirmed the protesters' worst fears. An analysis of the relationships between 43,000 transnational corporations has identified a relatively small group of companies, mainly banks, with disproportionate power over the global economy.
The study's assumptions have attracted some criticism, but complex systems analysts contacted by New Scientist say it is a unique effort to untangle control in the global economy. Pushing the analysis further, they say, could help to identify ways of making global capitalism more stable.
The idea that a few bankers control a large chunk of the global economy might not seem like news to New York's Occupy Wall Street movement and protesters elsewhere (see photo). But the study, by a trio of complex systems theorists at the Swiss Federal Institute of Technology in Zurich, is the first to go beyond ideology to empirically identify such a network of power. It combines the mathematics long used to model natural systems with comprehensive corporate data to map ownership among the world's transnational corporations (TNCs).
"Reality is so complex, we must move away from dogma, whether it's conspiracy theories or free-market," says James Glattfelder. "Our analysis is reality-based."
Previous studies have found that a few TNCs own large chunks of the world's economy, but they included only a limited number of companies and omitted indirect ownerships, so could not say how this affected the global economy - whether it made it more or less stable, for instance.
The Zurich team can. From Orbis 2007, a database listing 37 million companies and investors worldwide, they pulled out all 43,060 TNCs and the share ownerships linking them. Then they constructed a model of which companies controlled others through shareholding networks, coupled with each company's operating revenues, to map the structure of economic power.
The work, to be published in PLoS One, revealed a core of 1318 companies with interlocking ownerships (see image). Each of the 1318 had ties to two or more other companies, and on average they were connected to 20. What's more, although they represented 20 per cent of global operating revenues, the 1318 appeared to collectively own through their shares the majority of the world's large blue chip and manufacturing firms - the "real" economy - representing a further 60 per cent of global revenues.
When the team further untangled the web of ownership, it found much of it tracked back to a "super-entity" of 147 even more tightly knit companies - all of their ownership was held by other members of the super-entity - that controlled 40 per cent of the total wealth in the network. "In effect, less than 1 per cent of the companies were able to control 40 per cent of the entire network," says Glattfelder. Most were financial institutions. The top 20 included Barclays Bank, JPMorgan Chase & Co, and The Goldman Sachs Group.
John Driffill of the University of London, a macroeconomics expert, says the value of the analysis is not just to see if a small number of people controls the global economy, but rather its insights into economic stability.
Concentration of power is not good or bad in itself, says the Zurich team, but the core's tight interconnections could be. As the world learned in 2008, such networks are unstable. "If one [company] suffers distress," says Glattfelder, "this propagates."
"It's disconcerting to see how connected things really are," agrees George Sugihara of the Scripps Institution of Oceanography in La Jolla, California, a complex systems expert who has advised Deutsche Bank.
Yaneer Bar-Yam, head of the New England Complex Systems Institute (NECSI), warns that the analysis assumes ownership equates to control, which is not always true. Most company shares are held by fund managers who may or may not control what the companies they part-own actually do. The impact of this on the system's behaviour, he says, requires more analysis.
Crucially, by identifying the architecture of global economic power, the analysis could help make it more stable. By finding the vulnerable aspects of the system, economists can suggest measures to prevent future collapses spreading through the entire economy. Glattfelder says we may need global anti-trust rules, which now exist only at national level, to limit over-connection among TNCs. Sugihara says the analysis suggests one possible solution: firms should be taxed for excess interconnectivity to discourage this risk.
One thing won't chime with some of the protesters' claims: the super-entity is unlikely to be the intentional result of a conspiracy to rule the world. "Such structures are common in nature," says Sugihara.
Newcomers to any network connect preferentially to highly connected members. TNCs buy shares in each other for business reasons, not for world domination. If connectedness clusters, so does wealth, says Dan Braha of NECSI: in similar models, money flows towards the most highly connected members. The Zurich study, says Sugihara, "is strong evidence that simple rules governing TNCs give rise spontaneously to highly connected groups". Or as Braha puts it: "The Occupy Wall Street claim that 1 per cent of people have most of the wealth reflects a logical phase of the self-organising economy."
So, the super-entity may not result from conspiracy. The real question, says the Zurich team, is whether it can exert concerted political power. Driffill feels 147 is too many to sustain collusion. Braha suspects they will compete in the market but act together on common interests. Resisting changes to the network structure may be one such common interest.
When this article was first posted, the comment in the final sentence of the paragraph beginning "Crucially, by identifying the architecture of global economic power…" was misattributed.
The top 50 of the 147 superconnected companies
1. Barclays plc
2. Capital Group Companies Inc
3. FMR Corporation
4. AXA
5. State Street Corporation
6. JP Morgan Chase & Co
7. Legal & General Group plc
8. Vanguard Group Inc
9. UBS AG
10. Merrill Lynch & Co Inc
11. Wellington Management Co LLP
12. Deutsche Bank AG
13. Franklin Resources Inc
14. Credit Suisse Group
15. Walton Enterprises LLC
16. Bank of New York Mellon Corp
17. Natixis
18. Goldman Sachs Group Inc
19. T Rowe Price Group Inc
20. Legg Mason Inc
21. Morgan Stanley
22. Mitsubishi UFJ Financial Group Inc
23. Northern Trust Corporation
24. Société Générale
25. Bank of America Corporation
26. Lloyds TSB Group plc
27. Invesco plc
28. Allianz SE 29. TIAA
30. Old Mutual Public Limited Company
31. Aviva plc
32. Schroders plc
33. Dodge & Cox
34. Lehman Brothers Holdings Inc*
35. Sun Life Financial Inc
36. Standard Life plc
37. CNCE
38. Nomura Holdings Inc
39. The Depository Trust Company
40. Massachusetts Mutual Life Insurance
41. ING Groep NV
42. Brandes Investment Partners LP
43. Unicredito Italiano SPA
44. Deposit Insurance Corporation of Japan
45. Vereniging Aegon
46. BNP Paribas
47. Affiliated Managers Group Inc
48. Resona Holdings Inc
49. Capital Group International Inc
50. China Petrochemical Group Company
* Lehman still existed in the 2007 dataset used
Graphic: The 1318 transnational corporations that form the core of the economy