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DC police used sonic cannon to direct crowd flow during Women's March

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Re: DC police used sonic cannon to direct crowd flow during Women's March

#201

Post by sterlind »

jjoonathan wrote: post #180
ThrowawayNEF wrote: post #14

Is it just me or when did this become normal? I learned in Engineering class quite some time ago that it's theoretically possible to use the resonance frequency of the human body as a weapon. Back then this was something that everybody considered unethical. How have we ended up with things like tear gas and LRAD, that would be outlawed in military conflict but seem perfectly fine for "crowd control" purposes?

What's the Q of a human? My guess would have been "pretty low." Is that not the case?

[12.2Hz for males, 12.8Hz for females, evidently.](https://www.ncbi.nlm.nih.gov/m/pubmed/9306739/)

Using two LRADs emitting ultrasound to cause a difference tone, and some sort of laser range finder to observe oscillation and adjust a phase locked loop, it should be possible to resonate the bodies of people in a crowd at will.

as heinous as it'd be to implement this, I kinda want to try it. but that's how we've gotten into this pickle, in the first place.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#202

Post by azernik »

stevenjohns wrote: post #166
azernik wrote: post #98

Earlier quoted context omitted.

"Repeated/prodded thoroughly" matches all of the descriptions of the long-form interrogations by Israeli airline and airport security. If they got to the 100 shekels in his wallet, then that means they probably asked him about a lot of other things first, and searched his wallet, and probably tried to put together a timeline of exactly when he went where to try to find cracks in the story.

Not really. It was a standard run-of-the-mill search. The shekels are the only thing they were genuinely interested in. They couldn't comprehend why I had gotten it. It was bizarre.

Weeeeeeeeeeeird.

But then, I'm Jewish Israeli, so I don't have a lot of first-person experience with the full interrogation experience, just second-hand accounts from both sides of the table.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#203

Post by qbaqbaqba »

fencepost wrote: post #105

Before I'm willing to condemn this I'd want to know a lot more about how it was actually used. Was it used as a weapon or simply as an available bullhorn or announcement/PA system? I don't recall any press at the time about serious crowd control problems or the "weapon" use of LRADs, and a quick bit of searching now also doesn't show anything like that. Even the article notes "military grade versions that can send vo…

It's a very good question. In Poland police was also said to have used this device during an oppositions protest. However, it turned out it was used as a speaker. It wasn't used as a crowd control device because it isn't included in our Law about Police as a legal mean of enforcement. To make things more interesting it shouldn't have been bought at all (because it's usage is illegal), but it was bought anyway by our previous government that is our current opposition protesting today.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#204

Post by everdev »

sooheon wrote: post #92
everdev wrote: post #82

Earlier quoted context omitted.

You're right that there are many ways to profile, but race and religion have been historically pervasive profiling techniques. It does seem more fair to simply put everyone through the same process. If you're annoyed at why you (an innocent) have to be subjected to such stringent and time consuming security, that's how innocents who fit "the profile" might feel as well.

If those doing the profiling are interested in being successful, and race and religion prove to be ineffective indicators of threat, then such profiling should stop (or bombs will keep getting through at an inordinate rate). Otherwise, race and religion are simply observations about passengers which have value in directing attention.

Correlation != Causation

If we examine the background of anyone who has ever committed terrorism, every major race and religion would be covered. And so much of crime comes from social context, so at what point could you ever say: it's safe to assume that anyone with X ethnic background is not a threat. You can take any race and put them in a hostile, violent context and see them either continue the violence or die.

Or, if you say the majority of terrorists are men, so let's stop profiling women, I'm sure you would find more women committing terrorism. Then are women the greater threat or is it simply that we've made it harder for men to be terrorists?

I don't see a way to profile without affecting the statistics.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#205

Post by AlexandrB »

emodendroket wrote: post #171
AlexandrB wrote: post #165

Earlier quoted context omitted.

And the US has 10x the population density of Canada. Yet we manage it somehow (except for internet). I love how the US is simultaneously the most powerful economy in the world and completely hapless at putting any of that to use for the good of its citizens.

To be fair, the vast majority of Canadians live near Canada's southern border.

My main point is not that providing quality public services is easy but that excuses like "we don't have enough population density" are a red herring. The real hurdles are entirely political.

Some back of the envelope calculations:

Length of US/Canada border: 8,890km [1] Population of Canada: 36,708,083 [2]

Assuming ALL of Canada's population lives within 100km of this border a rough estimate of this area might be 889,000km^2 giving a population density of 41 people per square kilometre. This conservative estimate is in the same ballpark as the US population density of 33 people per square kilometre [3] with the caveat that this population is spread across a long, thin 9000 km ribbon increasing the cost of roads and any other infrastructure versus the US's more favourable shape. And let's not forget that Canada's GDP per capita is $46,437 while America's is $57,467 [4]. This is a factor of 1.24 in favour of the United States.

Given all this, why is the US incapable of providing the kind of single-payer healthcare that Canada does to its population?

[1] https://www.statcan.gc.ca/pub/11-402-x/2012000/chap/geo/geo-...

[2] http://www.statcan.gc.ca/tables-tableaux/sum-som/l01/cst01/f...

[3] https://en.wikipedia.org/wiki/List_of_countries_and_dependen...

[4] https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)...

Re: DC police used sonic cannon to direct crowd flow during Women's March

#206

Post by kevin_thibedeau »

dwyerm wrote: post #191
kevin_thibedeau wrote: post #159

Earlier quoted context omitted.

LRADs don't generate ultrasound. The worst they can do is create the brown note.

I'm pretty sure that they do. They're parametric speakers, like the 'Soundlazer[1]', that use a very loud ultrasonic carrier and make audible sound from the interference between the beams of ultrasonics. Even when an parametric speaker is playing 'silence', it is probably blasting 120dB of ultrasound. Soundlazer's faq on Kickstarted mentioned this explicitly: "...you will be hit with 120.5Db of sound pressure that yo…

They max out at 2.5kHz. All they can do is loud speech and infrasound.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#207

Post by belorn »

aalleavitch wrote: post #182
belorn wrote: post #161

Earlier quoted context omitted.

Researchers at Harvard made a study on which news paper focused on which candidate and was used by followers by each side ( https://dash.harvard.edu/bitstream/handle/1/33759251/2017-08... ). The washingtonpost had, like many others, a very clear bias in both which candidate they promoted and their intended reader demographic. I don't trust anyone marked clearly blue or red to make a trustworthy description about even…

The Washington Post has existed for 140 years and has won 47 Pulitzer Prizes. It's the newspaper that broke Watergate. You can acknowledge a news source for its editorial bias and still trust it not to print outright falsehoods on a regular basis. The Wall Street Journal is editorially right-leaning but that doesn't mean I think it prints lies, I will trust it regarding statements of objective fact up to the point th…

I don't doubt that they stays to the facts, but I also don't trust them to tell the truth.

Let me take an example story that was printed in most news papers after the election. Two facts: The number of new articles written during the election about the Clinton email scandal was twice as many as the Trump tape scandal, but news papers also wrote more than twice as much about the Trump tape scandal than the Clinton email scandal. Both are factual true, but any conclusion made on them is akin to falsehoods because they leave out the necessary context. What is missing is time, as in that news paper wrote about the Clinton email scandal the whole 6 months that the study looked at, while the Trump audio tape scandal was earthed only one month before the election date. As such looking at articles per day while each scandal was new, the trump scandal created significant more articles than any other month, while the long duration of the email scandal created a much higher total number of articles than those of the single month that the audio tapes were discussed.

But it is not news to say that an event stretched over 6 months can create more articles than a single month, or that the last month of an election generates a lot of news articles. It is something a Wikipedia article might mention to balance a paragraph, but it do not generate clicks from a political targeted audience. Lying by omission is technically not an outright falsehood, and they aren't required to make retractions to fix it, so both sides instead paints them selves as victims of the media and media is happy to write articles about it that tailors to their matching demographic. Money is gained and all that is lost is trust.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#208

Post by sooheon »

everdev wrote: post #204
sooheon wrote: post #92

Earlier quoted context omitted.

If those doing the profiling are interested in being successful, and race and religion prove to be ineffective indicators of threat, then such profiling should stop (or bombs will keep getting through at an inordinate rate). Otherwise, race and religion are simply observations about passengers which have value in directing attention.

Correlation != Causation If we examine the background of anyone who has ever committed terrorism, every major race and religion would be covered. And so much of crime comes from social context, so at what point could you ever say: it's safe to assume that anyone with X ethnic background is not a threat. You can take any race and put them in a hostile, violent context and see them either continue the violence or die.…

I agree with the gist of everything you've written here. And I think you're slightly missing the point.

> "so much of crime comes from social context"

Agreed. This is why I advocate taking that context into account. Not profiling would mean treating every single individual the exact same way, removing all social context from consideration.

> at what point could you ever say: it's safe to assume that anyone with X ethnic background is not a threat

This is not the point of profiling. The point is to build probability distributions, and hone them.

> I don't see a way to profile without affecting the statistics.

This is literally the point! You want to profile on such an exacting superset of factors (behavior, history, autonomous responses, forensics...) that you cause the incidence rate of terrorism to go down, across the board.

A brittle policy like "only screen middle eastern men" will of course get gamed, but that is terrible profiling. It builds a one-dimensional "profile"--you want a profile that is harder to fool, and based on actual behavioral cues.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#209

Post by sooheon »

emodendroket wrote: post #131
sooheon wrote: post #92

Earlier quoted context omitted.

If those doing the profiling are interested in being successful, and race and religion prove to be ineffective indicators of threat, then such profiling should stop (or bombs will keep getting through at an inordinate rate). Otherwise, race and religion are simply observations about passengers which have value in directing attention.

> If those doing the profiling are interested in being successful, and race and religion prove to be ineffective indicators of threat, then such profiling should stop I mean maybe if the profiling is being done by robots, but in reality I have my doubts.

I think humans can do this as well, they just need the right incentive structure (i.e. tied to actual results). CYA security theatre is not it.

Re: DC police used sonic cannon to direct crowd flow during Women's March

#210

Post by emodendroket »

AlexandrB wrote: post #205
emodendroket wrote: post #171

Earlier quoted context omitted.

To be fair, the vast majority of Canadians live near Canada's southern border.

My main point is not that providing quality public services is easy but that excuses like "we don't have enough population density" are a red herring. The real hurdles are entirely political. Some back of the envelope calculations: Length of US/Canada border: 8,890km [1] Population of Canada: 36,708,083 [2] Assuming ALL of Canada's population lives within 100km of this border a rough estimate of this area might be 88…

It isn't but I thought we were talking about infrastructure (there are clearly political factors at work there too of course).
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