Entries Tagged "alarms"
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This is interesting:
Some of the scenarios where we have installed video analytics for our clients include:
- to detect someone walking in an area of their yard (veering off of the main path) that they are not supposed to be;
- to send an alarm if someone is standing too close to the front of a store window/front door after hours;
- to alert security guards about someone in a parkade during specific hours;
- to count the number of people coming into (and out of) a store during the day;
In the case of burglary prevention, getting an early warning about someone trespassing makes a huge difference for our response teams. Now, rather than waiting for a detector in the house to trip, we can receive an alarm signal while a potential burglar is still outside.
Effectiveness is going to be a question of limiting false positives.
In 2006, writing about future threats on privacy, I described a life recorder:
A “life recorder” you can wear on your lapel that constantly records is still a few generations off: 200 gigabytes/year for audio and 700 gigabytes/year for video. It’ll be sold as a security device, so that no one can attack you without being recorded.
I can’t find a quote right now, but in talks I would say that this kind of technology would first be used by groups of people with diminished rights: children, soldiers, prisoners, and the non-lucid elderly.
It’s been proposed:
With GPS capabilities built into phones that can be made ever smaller, and the ability for these phones to transmit both sound and audio, isn’t it time to think about a wearable device that could be used to call for help and accurately report what was happening?
The device could contain cameras and microphones that activate if the device was triggered to create evidence that could locate an attacker and cause them to flee, an alarm sound that could help locate the victim and also help scare off an attacker, and a set of sensors that could detect everything from sudden deceleration to an irregular heartbeat or compromised breathing.
Just one sentence on the security and privacy issues:
Indeed, privacy concerns need to be addressed so that stalkers and predators couldn’t compromise the device.
Some movie-plot attacks actually happen:
They never touched the floor—that would have set off an alarm.
They didn’t appear on store security cameras. They cut a hole in the roof and came in at a spot where the cameras were obscured by advertising banners.
And they left with some $26,000 in laptop computers, departing the same way they came in—down a 3-inch gas pipe that runs from the roof to the ground outside the store.
The essay is about veganism and plant eating, but I found the descriptions of plant security countermeasures interesting:
Plants can’t run away from a threat but they can stand their ground. “They are very good at avoiding getting eaten,” said Linda Walling of the University of California, Riverside. “It’s an unusual situation where insects can overcome those defenses.” At the smallest nip to its leaves, specialized cells on the plant’s surface release chemicals to irritate the predator or sticky goo to entrap it. Genes in the plant’s DNA are activated to wage systemwide chemical warfare, the plant’s version of an immune response. We need terpenes, alkaloids, phenolics — let’s move.
“I’m amazed at how fast some of these things happen,” said Consuelo M. De Moraes of Pennsylvania State University. Dr. De Moraes and her colleagues did labeling experiments to clock a plant’s systemic response time and found that, in less than 20 minutes from the moment the caterpillar had begun feeding on its leaves, the plant had plucked carbon from the air and forged defensive compounds from scratch.
Just because we humans can’t hear them doesn’t mean plants don’t howl. Some of the compounds that plants generate in response to insect mastication — their feedback, you might say — are volatile chemicals that serve as cries for help. Such airborne alarm calls have been shown to attract both large predatory insects like dragon flies, which delight in caterpillar meat, and tiny parasitic insects, which can infect a caterpillar and destroy it from within.
Enemies of the plant’s enemies are not the only ones to tune into the emergency broadcast. “Some of these cues, some of these volatiles that are released when a focal plant is damaged,” said Richard Karban of the University of California, Davis, “cause other plants of the same species, or even of another species, to likewise become more resistant to herbivores.”
There’s more in the essay.
It’s hard work being prey. Watch the birds at a feeder. They’re constantly on alert, and will fly away from food — from easy nutrition — at the slightest movement or sound. Given that I’ve never, ever seen a bird plucked from a feeder by a predator, it seems like a whole lot of wasted effort against not very big a threat.
Assessing and reacting to risk is one of the most important things a living creature has to deal with. The amygdala, an ancient part of the brain that first evolved in primitive fishes, has that job. It’s what’s responsible for the fight-or-flight reflex. Adrenaline in the bloodstream, increased heart rate, increased muscle tension, sweaty palms; that’s the amygdala in action. And it works fast, faster than consciousnesses: show someone a snake and their amygdala will react before their conscious brain registers that they’re looking at a snake.
Fear motivates all sorts of animal behaviors. Schooling, flocking, and herding are all security measures. Not only is it less likely that any member of the group will be eaten, but each member of the group has to spend less time watching out for predators. Animals as diverse as bumblebees and monkeys both avoid food in areas where predators are common. Different prey species have developed various alarm calls, some surprisingly specific. And some prey species have even evolved to react to the alarms given off by other species.
Evolutionary biologist Randolph Nesse has studied animal defenses, particularly those that seem to be overreactions. These defenses are mostly all-or-nothing; a creature can’t do them halfway. Birds flying off, sea cucumbers expelling their stomachs, and vomiting are all examples. Using signal detection theory, Nesse showed that all-or-nothing defenses are expected to have many false alarms. “The smoke detector principle shows that the overresponsiveness of many defenses is an illusion. The defenses appear overresponsive because they are ‘inexpensive’ compared to the harms they protect against and because errors of too little defense are often more costly than errors of too much defense.”
So according to the theory, if flight costs 100 calories, both in flying and lost eating time, and there’s a 1 in 100 chance of being eaten if you don’t fly away, it’s smarter for survival to use up 10,000 calories repeatedly flying at the slightest movement even though there’s a 99 percent false alarm rate. Whatever the numbers happen to be for a particular species, it has evolved to get the trade-off right.
This makes sense, until the conditions that the species evolved under change quicker than evolution can react to. Even though there are far fewer predators in the city, birds at my feeder react as if they were in the primal forest. Even birds safe in a zoo’s aviary don’t realize that the situation has changed.
Humans are both no different and very different. We, too, feel fear and react with our amygdala, but we also have a conscious brain that can override those reactions. And we too live in a world very different from the one we evolved in. Our reflexive defenses might be optimized for the risks endemic to living in small family groups in the East African highlands in 100,000 BC, not 2009 New York City. But we can go beyond fear, and actually think sensibly about security.
Far too often, we don’t. We tend to be poor judges of risk. We overreact to rare risks, we ignore long-term risks, we magnify risks that are also morally offensive. We get risks wrong — threats, probabilities, and costs — all the time. When we’re afraid, really afraid, we’ll do almost anything to make that fear go away. Both politicians and marketers have learned to push that fear button to get us to do what they want.
One night last month, I was awakened from my hotel-room sleep by a loud, piercing alarm. There was no way I could ignore it, but I weighed the risks and did what any reasonable person would do under the circumstances: I stayed in bed and waited for the alarm to be turned off. No point getting dressed, walking down ten flights of stairs, and going outside into the cold for what invariably would be a false alarm — serious hotel fires are very rare. Unlike the bird in an aviary, I knew better.
You can disagree with my risk calculus, and I’m sure many hotel guests walked downstairs and outside to the designated assembly point. But it’s important to recognize that the ability to have this sort of discussion is uniquely human. And we need to have the discussion repeatedly, whether the topic is the installation of a home burglar alarm, the latest TSA security measures, or the potential military invasion of another country. These things aren’t part of our evolutionary history; we have no natural sense of how to respond to them. Our fears are often calibrated wrong, and reason is the only way we can override them.
This essay first appeared on DarkReading.com.
Beet armyworm caterpillars react to the sound of a passing wasp by freezing in place, or even dropping off the plant. Unfortunately, armyworm intelligence isn’t good enough to tell the difference between enemy aircraft (the wasps that prey on them) and harmless commercial flights (bees); they react the same way to either. So by producing nectar for bees, plants not only get pollinated, but also gain some protection against being eaten by caterpillars.
The small hive beetle lives by entering beehives to steal combs and honey. They home in on the hives by detecting the bees’ own alarm pheromones. They also track in yeast that ferments the pollen and releases chemicals that spoof the alarm pheromones, attracting more beetles and more yeast. Eventually the bees abandon the hive, leaving their store of pollen and honey to the beetles and yeast.
Mountain alcon blue caterpillars get ants to feed them by spoofing a biometric: the sounds made by the queen ant.
You might think that a Lego safe would be easy to open. Maybe just remove a few bricks and you’re in. But that’s not the case with this thing, the cutting edge of Lego safe technology. The safe weighs 14 pounds and has a motion detecting alarm so it can’t be moved without creating a huge ruckus.
Sidebar photo of Bruce Schneier by Joe MacInnis.