The First Smart Air Quality Tracker?

It is now almost 50 years since the first microprocessor, but it continues to revolutionize new areas. (First MPU = Intel 4004, in 1971, which Intel designed for a calculator company!) In concert with Moore’s Law and now ubiquitous wireless two-way wireless data transmission (thanks, Qualcomm!). smartphones have become a basic building block of many products.

A companion to explain what’s in your air, anywhere. Flow is the intelligent device that fits into your daily life and helps you make the best air quality choices for yourself, your family, your community.

Source: Flow, by Plume Labs | The First Smart Air Quality Tracker

Here is a quick review I wrote of the “Flow” pollution meter, after using it for a few months.  I wrote it as a comment on a blog post by Meredith Fowlie about monitoring the effects of fires in N. California.

I started with a particulate meter (a handheld model, not PurpleAir). Now I also have a Plume Labs unit running full time. It measures PM2.5, but also PM10, NO2 and Volatile Organic Compounds (smog components).
After a few months of use, I am impressed by the hardware. It shows very sharp peaks when we are cooking or something else disturbs indoor air. Sensitivity and consistency are both high.
Another advantage is that it is very portable. It’s actually designed to be worn on your belt while commuting, to discover local hot spots. All data is GPS flagged if you turn that feature on. I think their hope is to build time/location history for many major cities, using crowdsourced data.

Accuracy is harder to assess. The PM2.5 readings are much lower than on my other meter, and are usually below 5. We keep it in our bedroom, and while we use a Roomba frequently, I am skeptical about such low numbers. Readings above 20 happen less than once a week. But as usual with these devices, because outside meters (as discussed in the article) vary so much there is no way to calibrate it against other information.

The software that goes on your phone is “slick,” but it presents the information in a very limited format. It is optimized for use by commuters/runners. If you want to look at your data differently, such as over multiple days, you are out of luck.
Price is about $180. I compare alternatives for quite a while before selecting this one. It is considerably less expensive than other sensors that go beyond particulates.

Modern smartphones now allow revolutionary advances in portable measurements and in citizen science. They have huge computational power with highly standardized interfaces for application-specific hardware, such as pollution monitors, to link to. Instrument makers now need nothing more than a Bluetooth radio to give their devices graphical displays, real-time tracking and alerting, location flagging, months of data storage, and many other features that used to add hundreds or thousands of dollars to instrument prices.

Pollution measured over the course of a day as the owner travels. This is the display shown on my phone.

Play sound on multiple devices from your Mac

Mac OS simple sound mixer

Ever wanted to play sound through multiple audio devices on your Mac OS X system? It cannot be done with the normal Mac controls, but to my surprise there is a decent sound mixer built into the base Mac OS.

Step by step instructions: Play sound on multiple devices, including Internal Speakers, on OS X | Best Mac Tips

I have this setup for my 90 year old mother, so we can all watch TV at once:

  • HDMI from Mac to our Panasonic TV
  • Headphones plugged into the earphone jack on the Mac
  • Closed captions turned on for TV

The result is that we can turn her volume way up, while we listen over the TV’s internal speakers. The headphones, even at maximum volume, may not be quite loud enough for her. In that case, I will add a $25 earphone amplifier into the system.

Still missing: I cannot find Bluetooth headphones that are loud enough for her.

Second, I don’t know of anything similar for her phone.

Going back to school again – a shopping list | The Thesis Whisperer

Hardware and software list for new PhD students. It’s a good starting place. (I guess February is the start of the new academic year “Down Under.”)  Source: Going back to school again – a shopping list | The Thesis Whisperer

My additional suggestions:
1. Reference manager software is essential. EndNote is radically overpriced and behind in terms of features, but unfortunately is standard in certain fields. There are open source alternatives (Zotero). I use Bibdesk, which is only about $50.

2. A document manager is also essential. And I disagree with her comment about using a different manager for each source (PDF, web pages, etc.) To start with, Evernote is an OK but very lightweight document manager – it is not easy to find things once your library gets large (I have > 10,000 documents, but that is after years in academia). Better alternatives are:

  • EagleFiler
  • Devonthink (much more complex and correspondingly harder to learn, but also more powerful. For example, you can link to specific locations inside documents).
  • Both of these allow you to store ALL kinds of documents and to easily display, search, reorganize, and annotate them while still in the main application. For web pages, you have the option of storing as HTML, or converting to PDF.
  • A third option, which went through years of bugs but is apparently now OK, is Papers ( But it only has native support for PDF – everything else has to be stored as PDF. Still, if I were starting over I would give it a serious look.
  • Finally, Bibdesk or other reference managers may be OK for managing documents, although I’ve never tried it.

Scrivener and its ilk for writing you have discussed elsewhere.

Standards wars in home automation: don’t spend big $ yet

TL;DR It will take 5+ years for standards to get sorted out in home automation. Until they are, devices from different companies will not be compatible. Anything that you buy and install now will be inconvenient (you will need multiple interfaces) and become obsolete in a few years.

Now that there are many genuinely useful and modestly priced home automation devices (and I don’t mean smart refrigerators), we are ready to enter the rising portion of “the S curve” where penetration increases. Most of the devices can be retrofit, which will make uptake much easier.

But right now, most vendors have their own protocols. Common protocols are needed at 3 layers:  the user interface, such as a mobile phone/computer app (or web site), physical communication such as Bluetooth, Zigbee, or Wi-Fi, and data protocols (API’s, essentially). Most vendors appear to be moving toward a hub and spokes arrangement, where the hub handles communication to the user and outside the home, so there will also be competition for whose hub customers buy. Finally, I would add security as its own “layer,” since it is so important and currently completely neglected.

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Leave Your Laptops at the Door to My Classroom 

The research on this seems pretty overwhelming: laptops and cell phones in class hurt learning. Related issue: learning to listen.

Unfortunately in my more quant courses, they can be necessary at times. But if I had a way to turn off the Internet, I certainly would. (FCC makes wireless jamming illegal – for good reason.)

“My Galaxy Note7 is still safer than my car.” No, it isn’t.

The odds of dying in a car wreck are twice as high as this thing “exploding.” I’m keeping it.

Source: My Galaxy Note7 is still safer than my car. I’m keeping it

This author does an interesting calculation, but he does it wrong. The 100 Note7s that have exploded, out of 2.5M sold, were all used for 2 months or less since the phone has only been on the market that long. When you correct for this, the rate of fires over a 2 year ownership period is roughly 1 in 1000. (Probably higher, for several reasons.)

Second, lithium battery fires are nasty, smelly, and dangerous because they can set other things on fire. I speak from personal experience. Do you want to leave a device plugged in at night that may have a .1% chance of burning your house down over the period that you own it? I hope not.

His car wreck odds calculation (1 in 12000), by the way, may be per-year, but again he does not realize that it matters. But he is right that cars are plenty dangerous. I once estimate that at birth an American has a 50% chance of being hospitalized due to a car accident during their lifetime.

There are many other TOM issues to do with this Samsung Note7 recall. Clearly they have internal problems, and problems somewhere in management.