Tuesday, July 21, 2015

Corn in the backyard, 2015 -- weeks 10 & 11

July 12

The tenth week of growth added another 6 inches to the stalk height bringing the average height of most of the corn to about 112 inches. Growing degree days were over 15% below the historical average, but the ears continued to grow while most them had not yet experienced pollination.

We had plenty of rain the week before these pictures were taken, including over two inches in a couple of downpours on Saturday. This image shows that even the stalks in the wettest part of the field are developing ears, and you can see the standing water still present on Sunday morning.

July 19

Although the plants added a few more inches to reach 116 inches tall this week, the real news is now at the ears. Many ears have grown nicely and dark silks were evident on the majority of the plants. Although temperatures were warmer than normal (217 heating degree days compared to the historical average of 182), they were evidently not too hot to deter pollination, nor was the rain too consistent to interfere either. Despite the challenges this growing season has provided, it appears the corn is progressing at a normal pace.

For those keeping score, we've had seven Sunday mornings in which the clouds hid the sun during our photo session, and four sunny sessions.

Friday, July 17, 2015

Top 5 Blog Posts by Page Views

It's been awhile since we've reported which of the posts on this blog are most popular, and since a trend has established itself over the last four years, it's time for an update. Listed below are the five posts that have been viewed most as recorded by the statistics feature built into Blogger. Although I often have reasons to doubt the data, it's the best record I have to date. In order of popularity, I present the top five blog posts.

When we first reported the most popular posts in May of 2011, this post was only a few months old but still managed to rank #7 against many posts that had been around much longer. This post has been consistently popular since its publication and continues to rank near the top regardless of the time scale: views in the last month, week, or day. Comments left on the post indicate there are other do-it-yourselfers that have referred to my story, which is gratifying, but makes me wonder how they found my page?

Since Google refers more viewers to this blog than any other source, I've assumed most of the visits to this post came from Google searches on radon systems. I think that may be a faulty assumption. My search for "radon mitigation system installation" revealed that my blog post didn't show up in the first 62 pages of results, at which point Google refused to show me any more of the alleged 102,000 results for my search. Evidently some other sources are directing folks here, and at a pretty consistent rate since 2011.

2. Gutter Hanger Testing

This post is a perennial favorite as well, indicating to me that the need for clear answers on gutter hangers has not abated since 2009. This post was at the top of the list when we first reported ratings in 2011, but by the spring of 2013 it had surrendered the top spot to the radon system installation post. While now running far behind the #1 post, this post still has a comfortable lead over the third place post.

3. Freeport McMoRan Morenci Copper Mine

I suspect this post gets most of its views from folks looking for information on the company that runs the mine, but I still hold out some hope that there are a few people out there that appreciate my personal perspective of my tour of the mine in 2010. This post actually passed the gutter hanger post in popularity in early 2012, but conceded the first place position by fall of that year, and was passed by the radon installation post a few months after that.

4. Corn Growth Chart

I think it's appropriate that at least one of my corn posts is popular enough to be in the top five, since it seems every time I meet someone that has visited this blog they mentioned my corn growth posts. This post shows up on the second page of Google search results for "corn growth chart," and even appears near the top of the image search for the same term. If you put the phrase in quotes, it's Google's top result! I suspect that may have driven a lot of the visits over the last six years, but a scarcity of views recently may allow other posts to accumulate views more quickly and knock this one out of the top five.

5. Williamsburg in the Fall: Buildings

Of all our posts on Colonial Williamsburg (36 so far), this one from 2009 has most consistently held a spot in the top 10, although three other CW posts have visited the top ten as well. A Google search for "Williamsburg buildings" (quotes included) finds this post on the seventh page of results, but changing the search terms to "Colonial Williamsburg buildings" moves it up to the third page. Although this post is not far behind the #4 post, its views per day rate is almost identical, which means I don't expect it to move into the #4 slot very soon.

It's probably not surprising that all five of these posts are at least four years old. An older post has more opportunity to attract views, and has an advantage over newer posts on total views count. For that reason I decided to calculate views per day rates for the top ten posts, and others that were close to the top ten, but posted recently enough that their popularity over time has not yet been fully realized. Interestingly enough, the #8 and #6 posts for total page views rank in the top five for views per day.

Honorable Mention:  An Experiment in Greenwich

This post ranks #4 in views per day, but since it's less than three years old, it still only ranks #8 for total views. While writing this post, I finally realized why tripadvisor.es (Spanish version of TripAdvisor) referred so many visitors to my blog. On this page: http://www.tripadvisor.es/ShowTopic-g186338-i17-k6300068-Como_llegar_a_Greenwich_para_visitar_el_meridiano-London_England.html the fourth responder included a link to my post on Greenwich, and by doing so, helped boost the ratings of the post. I'm glad at least one person linked to this post, since it's one of my favorites.

Honorable Mention:  Basement Bathroom Project

Although this post gets the fifth most views per day of all my posts, I'm at a loss to explain why. Having lived through the project, the post brings back lots of fond memories, but the pictures only show the ugly stages of the project before the pretty, finished pictures were taken. Nonetheless, it's views per day rate continues to be strong enough that it should move into the top five for total views if its pace continues.

I'll try to remember to report these ratings again before another four years passes, especially if we have a change in the top five posts. In the meantime, you can elevate your favorite post in the standings by visiting it several times each day. Imagine the satisfaction you'll feel! I'll keep trying to post something at least moderately clever, and you keep refreshing your browser, and together we'll shake up the ratings!

Wednesday, July 8, 2015

Corn in the backyard, 2015 -- week 9

July 5

Even though the growing degree days for the week lagged the historical average 153 to 169, the stalks added two feet of height to reach 106 inches. The big news of the week, however, was the ears that finally made an appearance. The image above shows one of the most mature ears I could find, and probably less than half of the stalks were sporting tassels. Nonetheless, the ears are why this crop was planted in the first place, and we'll watch them closely until harvest.

Saturday, July 4, 2015

Does Outside Air Temperature Affect MPG?

Most of us that have driven vehicles in cold weather have recognized that they consume more fuel as the outdoor temperature drops. We might attribute it to letting our cars sit and idle in order to maintain a warm interior, or we might surmise that slippery road conditions reduce fuel efficiency. While both of those factors decrease fuel efficiency, I've gathered some data that indicates the temperature of the ambient air also affects the efficiency of internal combustion engines.

I began collecting data on February 9 this year using my 2013 Volkswagen Passat TDI SE with a diesel engine and manual transmission. My car has a meter that calculates average fuel economy (miles per gallon) for each trip, so I've been recording the fuel economy for my trip to work each morning. My route is identical each day and while my data doesn't represent an entire year, the temperature range is wide enough that I don't expect significant changes in the data over the next seven months. Road construction on my route added a detour beginning April 2, which increased the distance and added more 45 mph zone driving to the trip. I've noted the route change in my data, but what's presented here includes data from both routes.

My Volkswagen owner's manual includes this chart that predicts an increase in miles per gallon as trip length increases and also as temperature increases.  Volkswagen's chart implies that my fuel economy would increase further if my commute were longer than my current 30.8-mile trek. I attribute that effect to the inefficiency of an internal combustion engine at temperatures lower than the normal operating temperature, and to a lesser extent the higher losses in the powertrain due to cold lubricant. I have observed that it takes about 7 minutes for the temperature gauge to settle at the normal operating temperature in the winter, while it only takes about 5 minutes in the summer. Since my data covers nearly the same route every day, my chart doesn't duplicate Volkswagen's, but includes more temperature data than VW's two series.

My data indicates a pretty strong correlation between increasing ambient temperature and increasing fuel economy. The regression curve added to the chart reveals that the correlation is almost linear, but a slightly better fit to a second-degree polynomial with a stronger effect at colder temperatures. Although the coefficient of determination (R²) is relatively high at 0.8172, the scatter in the data convinces me that there are other variables affecting fuel economy besides temperature. Wind, traffic congestion, and speed are all obvious effects that probably contribute to the data scatter above. Some of these are out of the driver's control (wind or road conditions), while driving behavior clearly affects mpg and is clearly in the driver's control.

For my data, I've tried to accelerate consistently from one day to the next, I set the cruise control to the same speeds as much as possible, and fortunately traffic density does not often affect my speed at the time of day I make my commute. To reduce the variables related to air temperature, I drive no differently when the engine is cold in the winter than I do in the summer, i.e. my car doesn't sit stationary while "warming up" in the winter.

I chose one temperature each day based on the temperature recorded by the National Weather Service even though the thermometer in my car leads me to believe the temperature may vary by a few degrees over my route. More complex data gathering and analysis is possible, but is not included in the data I've presented. Since temperature alone does not represent the only effect on fuel economy, I've also collected data on other variables that should prove insightful in understanding fuel economy trends. Those data will be presented in future posts right here. In the meantime, it has been comforting each day to recognize a factor out of my control that can be used to predict fuel consumption for that trip.