Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.
  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?
    New to Twitter?
    Sign up
marcan42's profile
Hector Martin
Hector Martin
Hector Martin
@marcan42

Tweets

Hector Martin

@marcan42

If it ain't broke, I'll fix it! I'm porting Linux to Apple Silicon Macs at @AsahiLinux. http://patreon.com/marcan  | http://github.com/sponsors/marcan 

Tokyo, Japan
marcan.st
Joined May 2009

Tweets

  • © 2021 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list

    Under 100 characters, optional
    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. /GriFFin PS3CRUNCH‏ @PS3Crunchnet 5 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marcan42

      Alot of info on the subject in this research paperhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4786042/ …

      1 reply 0 retweets 2 likes
    2. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @PS3Crunchnet @marcan42

      (1) Hi. Yes we have quite a lot of info on this. I put together a series of papers for a special issue of Journal of the Acoustical Society of America on this. There are about a dozen paper listed on https://asa.scitation.org/topic/special-collections/uia2018?SeriesKey=jas … and you should be able to download them. If not...

      1 reply 0 retweets 0 likes
    3. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (2)..let me know. Also the original paper you cite https://royalsocietypublishing.org/doi/10.1098/rspa.2015.0624 … has a follow-up at https://royalsocietypublishing.org/doi/full/10.1098/rspa.2016.0828 … There is a project website at https://www.southampton.ac.uk/engineering/research/projects/are-some-people-suffering.page … There’s more...

      1 reply 0 retweets 0 likes
    4. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (3) A video showing how smart phones & tablet computers can detect ultrasound in air is at https://youtu.be/RhFHCrcDtvM  (use in conjunction with Appendix A of the paper you first found). I set up an Instagram hashtag using the hashtag #UltrasoundInAir. to which folk upload spectra

      1 reply 0 retweets 0 likes
    5. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      Timothy Leighton Retweeted University of Southampton News

      (4) Just been told about this https://twitter.com/uosmedia/status/1167412086839947265?s=21 … Have not read it myself

      Timothy Leighton added,

      University of Southampton News @UoSMedia
      🔊 "When sound becomes hostile"... @Prof_Leighton of @UoSEngineering talks to @CNNStyle about cities using high frequency sounds as a deterrent to unruly behavior. Read what he had to say to @jacoprisco here 🔽 https://edition.cnn.com/style/article/hostile-sound-design-scn/ …
      1 reply 0 retweets 0 likes
    6. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (5) Ok I just read it. H sentences quoted from me were not, I am certain, following on from one another in the way it has been edited. So when I talk about permanent or temporary hearing loss, that it when I am talking about very high levels indeed at frequencies an individual..

      1 reply 0 retweets 0 likes
    7. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (6) ..hear(which may be above 20 kHz if their hearing can achieve that). It is talking abut extreme levels you would not encounter in a public space so don’t be unduly alarmed. They levels you encounter will bring annoyance, anxiety, headaches (possibly as result of tensing...

      1 reply 0 retweets 0 likes
    8. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (7)...neck muscles etc). Where I said if you can hear an ultrasonic frequency it will adversely affect you, that was in context of there being a narrowing window in amplitude as you do to higher frequencies, whereby the amplitude that is annoying is only a little louder than...

      1 reply 0 retweets 0 likes
    9. Timothy Leighton‏ @Prof_Leighton 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet @marcan42

      (8)..the amplitude at which you can just hear it (the amplitude difference between the two thresholds is much larger at lower frequencies). So all in all I would communicate a more contextualized message than CNN, with it’s limited space, edited up for me.

      1 reply 0 retweets 0 likes
    10. Hector Martin‏ @marcan42 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @Prof_Leighton @PS3Crunchnet

      Hector Martin Retweeted Hector Martin

      Thanks for the info! FWIW, the ones I'm talking about here are sold as rat deterrents, and claim to put out 19kHz at 136dB. They all all over Tokyo. I wrote a rather enthusiastic thread about them recently.https://twitter.com/marcan42/status/1162697281474142208?s=19 …

      Hector Martin added,

      Hector Martin @marcan42
      To all the senile assholes who think scaring off cats by blasting 19kHz at ear-damage levels all over shops in Japan is a good idea: I know you can't hear it, but I can and IT FUCKING HURTS. FOR LIKE HALF AN HOUR AFTER I PASS. STOP IT. pic.twitter.com/Tyd7HHJgg3
      Show this thread
      2 replies 0 retweets 0 likes
      Hector Martin‏ @marcan42 6 Sep 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marcan42 @Prof_Leighton @PS3Crunchnet

      I can definitely hear the sound and it causes me physical distress (though not debilitating, it's not harmless either); I've also heard many stories of people being affected but not realizing that the cause is a sound. I'm worried about it actually causing lasting hearing damage.

      9:46 AM - 6 Sep 2019
      1 reply 0 retweets 0 likes
        1. New conversation
        1. Hector Martin‏ @marcan42 6 Sep 2019
          • Report Tweet
          • Report NetzDG Violation
          Replying to @marcan42 @Prof_Leighton @PS3Crunchnet

          It's insidious, because the inability to localize the sound, and not being used to sounds that high, make it difficult to immediately recognize it as such. I've been in places where something felt off but only upon getting close enough to the emitter did I realize what it was.

          1 reply 0 retweets 0 likes
        2. Hector Martin‏ @marcan42 6 Sep 2019
          • Report Tweet
          • Report NetzDG Violation
          Replying to @marcan42 @Prof_Leighton @PS3Crunchnet

          I'm interested in taking calibrated measurements of this. Do you have any suggestions as to what to use for a calibration standard? I have an omni measurement microphone that should be flat enough, I'm thinking maybe I can calibrate the overall gain against a sound level meter.

          1 reply 0 retweets 0 likes
        3. Show replies

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2021 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info