Solar Eclipse 2017

We had fun watching the eclipse today.  Livermore had ~75% occlusion at peak.  It was also Heather's first day of school (separate post coming).  They took the kids outside to watch pinhole cameras and then let them use eclipse glasses one-at-a-time so they could ensure they were being worn properly.

Heather helped me make eclipse cookies yesterday.

My sugar cookie skills could use some work...

Corinne got a kick out of the eclipse proclaiming, "Moon! I see the moon!" (by which she, of course, meant sun).

We used the colander to get pinhole-camera-style shadows.

And I had my camera set up with filters taking pictures.  I just kind of guessed at settings.  Some came out better than others.  Here's the picture from the peak eclipse:

And here's one I got as it was ending where you can see a line of spots.  I don't know if they're technically sunspots, but they weren't just dust on my lens--they stayed with the sun throughout the event.

My weather station noticed the eclipse too:

The variations in the readings are due to varying cloud cover that, thankfully, almost completely cleared out during the eclipse.

The temperature even dropped a hair:

10 Years with a 2007 Honda Civic LX

I got my 2007 Honda Civic LX in April 2007.  It's now just over ten years old and going strong.  I just passed 90,000 miles.  I fully expect it to keep going for another 10 years, though I may decide to swap it for an electric vehicle before it's totally worn out.

In 10 years I have had zero issues in terms of reliability or mechanical functionality.  It has received all services as scheduled by the built-in "Maintenance Minder" system.  It is on its third set of tires, its second set of brake pads, and its third battery (all counts include the factory-installed items).

Efficiency has been consistent though it appears to be slowly dropping, but that might be a false interpretation of the data as, since we bought the Odyssey, the Civic no longer goes on long trips and has none of the up-ticks in efficiency gained from long highway traveling.

The lifetime efficiency is 29.86 miles-per-gallon (total miles traveled divided by total gallons of gas consumed; not the average of the per-tank efficiencies).

The amount of driving I've done with the Civic has been quite consistent over the years.  You can see some areas of rapid increase which signify long car trips driven over just a few days or weeks.

Overall, it has been a great car, though not without some minor annoyances.

The minor annoyances

A few of the LED segments on the speedometer display flicker, especially in hot weather.  Probably a weak piece of solder or something that becomes inconsistent in the heat.  Slightly annoying, but not a big deal.

The driver-seat height adjustment seems to slowly sink back down.  The height adjustment is a pneumatic system (as far as I can tell) that I think slowly leaks out the air pressure and causes the seat to drop back down to the bottom.  I usually pump it back up once a month or so and I only move it up a centimeter or two so it's not a big deal.

The driver-side window auto-retract system is overeager.  That's the system that prevents you from closing the window on an object when you use the "auto close" feature by pulling the switch all the way up.  The window will reach about an inch from closing and then retract back down.  Holding the switch overrides the auto-retract system.  So, again, slightly annoying, but not a big deal.

Honestly, those three things are the only functionality issues with the entire vehicle.  No mechanical issues, just minor annoyances.

Here I'm excluding recall work which could have affected the vehicle's reliability/safety, but was corrected for free and a priori to any incident.  The only particularly notable ones have been the possibly faulty O-ring on a speed sensor which may cause wheel failure and the faulty airbag inflater (part of the Takata recalls).  Both of which were corrected without issue.

The paint problem

The biggest problem with the car has been paint failure.  Several years ago Honda issued a voluntary recall due to an identified issue with paint longevity, but I misread the notice and missed the window to have them pay for some repainting.  Which may be somewhat moot.  The recall was for paint failure on the hood, roof, and trunk--which I had in great quantity--but I also had paint failure on the door panels and fenders.  I'm sure part of the problem was my not regularly cleaning and waxing the car, but even so, the paint should have held up better (which Honda admits).

In anticipation of owning the Civic for another 10 years I decided to get it repainted to both protect the metal and so it doesn't look terrible.

The first picture does not do a good job of exposing the differences from before (top) to after (bottom):

But once we start looking at the details it becomes obvious.  Left is before, right is after.

Top is before (obviously), bottom is after:

Here's to another 10 years!

The Weather in our Kingdom

Jess got me a weather station for my birthday which is now installed up on the roof:

The unit is an Ambient Weather WS-1400-IP.  It reports temperature, humidity, wind speed, wind direction, rainfall, solar radiation, etc.  It comes with an indoor unit that also reports inside temperature and humidity.

The data is sent to and you can find it here:

But, wunderground can be a little flaky, so I'm also capturing the data into my own database and serving it up.  On the sidebar of the blog you can find a widget that looks like this:

I'm using the "Weather Station" WordPress plugin to read a Cumulus-style file.  Now, the Ambient Weather ObserverIP unit does not produce the Cumulus "Realtime.txt" file that the WordPress plugin needs.  But, I have programming super powers.  So I wrote a shim that scrapes the data from the ObserverIP web interface and writes out a "Realtime.txt" file that I serve up for the WordPress plugin.

I also write out a human-readable page with the weather data on it you can see here:

It's not very pretty right now, but it's up and running, updating every 5 minutes.  I'll get around to improve the aesthetics at some point.

Having the indoor and outdoor sensors I'm thinking I'll have to write up something that will notify me when the temperatures outside and inside cross so I'm alerted to open or close the windows as appropriate.  But I haven't got that far yet.

The shim I wrote to put all these pieces together is available on GitHub:

It's just a Python script set to run every 5 minutes via Cron.  It scrapes the data off the ObserverIP unit, formats it and inserts it into the SQLite database, computes daily high/low values from the stored data, and writes Realtime.txt and index.html into a folder being served by Apache.

How's That Roof Working Out?

Our house needed a new roof when we bought it.  There wasn't anything particularly wrong with the roof, but it was 30 years old and worn out.  When we replaced the roof we went with light-colored shingles, added ridge venting, used radiant-barrier sheathing, and upgraded the attic insulation to a minimum of R38.

Well, now it's been a few years and I have some data (thanks PG&E for making usage history available for download in CSV format) so it's time to see how well all that stuff is working out for us.

Before we start, some caveats about the data.  I only have 1 year of data from before the roof replacement, so it's not very stable data.  For the 3 years after, I've averaged each month to obtain more stable information.  The graphs start in December because the new roof was put on during October.  So December is the first full bill after the roof was completed.

The gas data is very consistent.  We have a gas dryer, gas water heater, and gas furnace.  Our laundry and hot-water usage is probably fairly consistent throughout the years (with a small increase in both when Corinne joined the family), so the change in therms seen from before to after should be pretty focused on heating.  We've heated the house to approximately the same temperature throughout each winter so it should be a very stable comparison.

The electrical usage, however, is much less stable.  Usage patterns have changed as Heather has grown, we've switched TVs, upgraded computers, more hard drives spinning, more often running dishwasher, etc.  So the comparisons for usage from before and after are much more muddied.

Let's go to the data.


The gas usage shows an obvious reduction in gas usage throughout the winter months with equivalent usage during the summer.  This seems like pretty solid evidence that the upgraded insulation is making a difference.

The total therms used in 2013 was 503.  The average therms per year from 2014-2016 was 412.7.  An 18% reduction.  At an average of $1.29 per therm, this results in annual savings of $117.


Sadly, the electrical usage doesn't show an obvious dip during the summer months.  It actually shows a dip for the winter months which I presume must be related to the cost of running the blower on the furnace which didn't need to run as much as evidenced by the reduced gas usage.

Regarding the summer months, the 2013 data is not very good to begin with.  This was our first year in the house and we were adjusting our usage.  The spike in July 2013 would have been our first hot month in the house (July bill, for June usage) and we ran the air conditioner liberally.  When we saw the power bill, we adjusted the air conditioning to reduce costs as seen in significant drop in usage in August.

The uptick in January is most likely due to Christmas lights.

Although there was not a clear drop in usage throughout the summer as I was hoping, there was an overall reduction. The total kilowatt-hours used in 2013 was 4599.  The average usage per year in 2014-2016 was 4344.3.  A reduction of 6%.  At an average of $0.17 per kWh this results in annual savings of $42.  However, due to the nature of the 2013 data the validity of this claim is suspect.

Due to the many confounding variables on the electrical usage (mentioned in the opening paragraphs), I don't think this data can say that the high-reflectivity shingles, ridge venting, and radiant barrier were ineffective upgrades, but clearly they weren't obvious wins either, about which I'm a bit disappointed.

If we assume the data is valid as presented then the net change is $159 per year in savings.  If we were to assume the entire benefit seen is due to the combined effect of the insulation and roof upgrades (and not changes in usage patterns), then the break even point of the upgrades would be ~38 years.  Which is longer than the expected life of the roof (30 years).  However, the insulation and radiant barrier are one-time expenses.  Unless the roof fails catastrophically neither one should need to be replaced when the next roof is installed.

The net effect is that my data doesn't show the upgrades to have been a definitive win compared to a standard roof, however, I believe the electricity usage data is too inconsistent from year to year to be reliable to make any strong claim.  If I had a few more year's worth of data from before the roof replacement I'd be able to make stronger claims about the effect.

Facebook's Image Recognition/Tagging System

I've noticed recently that Facebook has been applying an automatic image recognition/tagging process to any pictures that are uploaded to their system.  The general idea is to get a computer to "understand" what's in a picture.

In Facebook's case, images are given a textual description automatically which is used to provide meta-data that can be accessed by screen-readers (used by the visually impaired when using computers).  This isn't about facial recognition (though Facebook is doing that as well).

For example, I came across this picture from a friend of mine:

Which Facebook's artificial intelligence system automatically tagged with this information:

Image may contain: sky, twilight, outdoor and nature

Automatic image tagging/recognition has been a popular field of research, but this is the first time I've seen it actually used in a production system for something useful.

It's pretty good too.  Here's one of interest to the Dickerson family at large:

Which Facebook automatically describes as:

Image may contain: 8 people, people smiling, people standing and indoor

I just found that interesting.  That's all.