rcomeau

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rcomeau
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  • Apple Watch sensor has racial bias, claims new lawsuit

    MacPro said:
    I can't see what Apple could do?  If they improved the sensitivity wouldn't that just make measurements better for light skins too, thus maintaining the differential?  It's physics not bias. 
    I don’t know what wavelength of light they use for these but there probably is a range in the non visible spectrum that could be used where skin tone would be irrelevant.
    Pulse oximetry depends on the differential absorbance of 2 (or more) different frequencies of IR light in the blood, specifically the oxygenated and deoxygenated haemoglobin. You can pick 2 IR wavelengths where the absorbance curves of oxi and de-oxi cross each other (typically pick one <700nm and one >800nm. Acquire relative intensity (changes in time) of both these wavelengths and you can fit them to a curve using something called the modified Beer-Lambert law to get an estimated change in blood oxygenation. You have to pick wavelengths that are on the right spots on the curve as well as what wavelengths of LED are actually available and affordable (only a new nm difference can mean a $1 LED or a $100LED due to the material in the LED that emits the light). This is not an easy problem to solve, other than blasting more light in, but you then run into concerns over heating the skin (absorbing IR light means conversion into heat) as well as power consumption and safety (too intense and you run the risk of eye damage if some fool stares into the back of the watch with the LEDs on. Not an easy fix.
    anonymouseradarthekatravnorodomh4y3sbeowulfschmidtMacocalypse
  • Fatal helicopter crash likely caused by dropped iPad

    AppleZulu said:
    This is irresponsible reporting. The headline and lede make it seem like this was somehow a failure on the part of the iPad itself. It was not.

    Read on, and you'll understand that the issue was that, once dropped, the iPad became a wedged-in obstruction to flight control mechanisms. The same would've been the case if the dropped item had been a Microsoft Surface, or a paper notebook in a rigid binder. There is no fault in the hardware design or software operation of the iPad itself.
    I think anyone can quickly assess that the iPad was not responsible. I recall a Harrier jet crash decades ago with a similar cause. The ground lost contact with the jet and it flew out to sea. Other jets were scrambled and they noted that the canopy was gone and the pilot was missing. The plane eventually crashed and the pilot found deceased in the woods somewhere. Investigation determined that a hand-held flashlight fell under the seat and when the pilot changed the seat orientation (maybe after turning into the sun), the flashlight wedged under the seat ejection actuator cable. As the seat moved, the cable got pulled and the seat ejection rockets fired the pilot through the canopy. The cause was termed "accidental extraction of crew". Remedy was to tie all loose items to a string to prevent it from getting under the seat.
    williamlondonBiCCavon b7
  • Apple employee petition demands flexibility against return-to-office policy

    mac_dog said:
    Spoiled brats? I don’t know about this, as I don’t know the particular people involved. I’m glad some of you do. 

    I agree this should be handled with immediate managers. They would take the responsibility if their division fails to meet productivity requirements. 

    They should be required to prove their increased productivity from home vs office. Simple enough to do and it’s measurable. 

    Both sides should be open to the scrutiny that’s required to make this a fair arrangement. 
    Not everything is measurable and companies that reply too much on measuring usually don't do anything creative. A lot of the benefits of being in person in groups are the random conversations that spark the ideas that changes things. KPIs (key performance indicators) are overrated.
    prolinedocno42kurai_kagedewmeapplejakesFileMakerFeller
  • Apple Pencil functionality compromised with third-party iPad parts

    Amazing to see all the fabricated assumptions defending Apple's decision to prevent third party repairs. Not qualified you say. How do you know if they are qualified? You assume this to defend Apple's position. Apple should not be held responsible if an "unqualified" person uses non Apple parts. Of course Apple is nor responsible. Who in their right mind would blame Apple? The warranty would be voided. Of course the warranty would be voided. If it were under warranty, they'd have taken it to Apple for free repair in the first place!

    The argument here is that mane repairs can be carried out by competent techs with access to parts but Apple (like many companies) choose to discourage this for money and to make their lives easier by not having to deal with botched repairs. The other side of the argument is that consumers have rights (companies have certain legal obligations in this world) and one right is the right to reasonable repairs for devices where reasonable repairs are possible.
    mr. hmuthuk_vanalingamwilliamlondonMystakill
  • AirTags catch United Airlines in lie about missing luggage

    omasou said:
    At no time was she smart enough to inform the police so that they could apprehend the United baggage handler who is stealing luggage?

    Instead she posts to Twitter to guaranteeing the perp will not be identified.
    Ah yes, when all else fails - blame the victim! Insult her intelligence for trying to get the airline charged with her belongings to handle it. 

    Had she gone to the police first you people would be saying she could have dealt with the business first. Roll eyes 
    Umm, she got the bag back. It seemed it was with the delivery people and other than being slow and not informative of the process, a bag (likely a bunch of bags) did not make it to the luggage carrousel and and after a long delay, it was delivered to the owner in the end. Sometimes it is not a good idea to see how the sausage is made.

    I had bags sit at an airport where I missed my original connection and the bag was not placed on the next flight with me (and some fellow passengers). I saw the bag sit there for 3 days before the bag was finally forwarded to the local airport. I was unable ti reach a human being to actually tell them where the bags were, and the only time I was able to speak to someone who knew anything was watching the AirTag move form the airport to some commercial budding. I was able to streetview it and saw a courier sign on the building. I called the number on the sigh and spoke to the delivery people who confirmed they had he bag and were bringing it to the hotel.
    ravnorodomMrBunsidemystigo
  • Parallels Desktop 17 brings Windows 11 to Mac with enhanced M1 support

    Many if us in the business world (e.g. engineering where a few essential apps like Soidworks or Altium are the standard) will pay whatever it takes. While 95% of my apps are macOS (including the app we develop and sell to our customers), some industries are locked into a standard. I'd LOVE a real-world macOS native alternative for Solidworks (including  macOS native Solidworks!), but given reality of the world, this hopefully will be palatable. 
    GeorgeBMacwatto_cobra
  • Apple Watch infringes Masimo pulse oximetry patent, rules judge

    chadbag said:
    Applejacs said:
    Ok, so Apple cuts a check for how much?

    Ideally, it would be the amount of money they made from the infringement.  But for a long time, it's been well worth it for Apple to infringe and then pay some pittance to make the problem go away.  The only way to stop infringement is to impose penalties that actually matter.

    I know exactly how likely that is though, given how much corporations "contribute to" legislators.
    Pray, tell.  How do you calculate how much Apple made from the claimed infringement?  If such a simple matter you should be able to enlighten us on the method. 

    (I said “claimed” as the matter is not settled. This was just the next step). 
    Simple. File the case in that county in Texas that seems to be good at adding massive punitive damages to these cases, so the infringer ends up on the hook for hundreds of millions (which gets reduced later by some other court, but is still a big enough number to mater).
    williamlondon
  • Apple sets April 11 deadline for corporate return to office

    I agree that from an employee's perspective, WFH has obvious benefits for many (not all though as many of our employees prefer separating home and work). From a business perspective, WFH is not ideal on many fronts (employee retention aside, which will likely lead to at least some WFH just to retain talent). The problem is it is hard to quantify the benefits of having your team in the same place. It is hard to quantify the value of the random interactions that only happen when you bump into someone and exchange some random ideas. In general, WFH reduces creativity, makes it harder to build a cohesive, trusting team and creates stratified relationships. What happens to employees that need to be in a lab to access hardware? They need to be in the office. Do they resent those can work from home? Employees who come in will get more facetime with their boss which will likely lead to quicker advancement than those who only check-in minimally via zoom. Will that cause resentment? Many people get a lot of personal gratification being part of a team and being present is important to nurture those relationships.

    WFH is like the old mail order businesses where you just stuff envelopes for pennies/envelope. Your job has to be commodified to be viable as WFH. If you want to create, contribute and be part of something special, WFH might not be the best way to go. I predict companies that adopt permanent WFH will either change their minds, or will be overtaken by more efficient and creative companies. 
    JWSCdewmebyronlmacxpress
  • Intel Windows not coming to M1 VMware Fusion, ARM Windows licensing unclear

    lkrupp said:
    If you need to run Windows then buy a Windows PC.
    Not all of us are lucky enough to have everything they need on macOS. I've managed to get down to pretty much one thing on Windows, but a doozy: SolidWorks. There is no  macOS version (nor is there a serious competitor either) and it is one of the standards in the field, which is essentially Windows based. Yes, I am one of maybe 50 who needs this, but I can still lament and I don't look forward to carrying a second laptop just so I can bang out that next prototype while on a long flight (when I get to fly again!).
    dysamoriadewmewatto_cobra
  • Apple Watch sensor has racial bias, claims new lawsuit

    rcomeau said:
    MacPro said:
    I can't see what Apple could do?  If they improved the sensitivity wouldn't that just make measurements better for light skins too, thus maintaining the differential?  It's physics not bias. 
    I don’t know what wavelength of light they use for these but there probably is a range in the non visible spectrum that could be used where skin tone would be irrelevant.
    Pulse oximetry depends on the differential absorbance of 2 (or more) different frequencies of IR light in the blood, specifically the oxygenated and deoxygenated haemoglobin. You can pick 2 IR wavelengths where the absorbance curves of oxi and de-oxi cross each other (typically pick one <700nm and one >800nm. Acquire relative intensity (changes in time) of both these wavelengths and you can fit them to a curve using something called the modified Beer-Lambert law to get an estimated change in blood oxygenation. You have to pick wavelengths that are on the right spots on the curve as well as what wavelengths of LED are actually available and affordable (only a new nm difference can mean a $1 LED or a $100LED due to the material in the LED that emits the light). This is not an easy problem to solve, other than blasting more light in, but you then run into concerns over heating the skin (absorbing IR light means conversion into heat) as well as power consumption and safety (too intense and you run the risk of eye damage if some fool stares into the back of the watch with the LEDs on. Not an easy fix.
    The Beer-Lambert law is pretty much the attenuation due to the imaginary part of the complex (real plus imaginary parts) index of refraction of the material (in this case the human tissue). The real part controlling the change in phase as the light propagates and so the angle of refraction. For a given material the index of refraction will have peaks and valleys in it described empirically by the Sellmeier equation. Basically the engineer would have to find a frequency of light where the imaginary part of the index of refraction isn’t significantly effected by the melanin in the skin. But as you mentioned whether or not it is economically practical depends on the availability of LEDs in that range. Bandgaps of LEDs can be tuned using structures like quantum wells though.
    Thats not correct. When light enters a medium, it can reflect, refract or be absorbed. Once light gets a few mm into the skin, it no longer has a coherent direction so it is treated as diffuse light (and phase is not relevant here). You can see this effect by shining your iPhone light through your finger. The basic mechanism being measured in a pulse oximeter (we manufacture a NIRS device that shines into the head and measures changes in blood-ox on the surface of the brain) is changes absorption (see https://www.researchgate.net/figure/A-schematic-of-how-the-fNIRS-works-with-the-absorption-spectra-of-HbO2-and-Hb_fig1_316156990) for the oxi and de-oxi absorption vs. IR wavelength curves that dictate how this works.
    elijahg9secondkox2