Wednesday, September 18, 2013

A 36 Kilometer Greenway Bicycle Ride

A 36 Kilometer Greenway Bicycle Ride

A beautiful September day, temperature in the low 70s.  Gentle breeze, blue skies.  Perfect for a bike ride.

Here are the stats: Note:  The route URL below bit off since I actually rode around Shelly Lake first rather than last, as is indicated by the distance markers.

Route ....
Time ...... 2 Hours 20 Minutes
Distance .. 36 Kilometers
Speed ..... 15 Kilometers Per Hour (18 Not Counting Rests)

I rode down Yadkin Drive to where it crosses Crabtree Creek and then traveled up the greenway to where Crabtree Creek and Lead Mine Creek join and followed the greenway up Lead Mine Creek to Shelly Lake.  

I rode around the east side of Shelly Lake and followed the greenway up Lead Mine Creek to Longstreet and Bent Creek Road where I turned around.  I rode back down the greenway to Shelly lake and rode around the west side and continued down the greenway following Lead Mine Creek to where it joins Crabtree Creek.

I then followed the greenway up Crabtree Creek to Crabtree Valley Mall and then up Blue Ridge Road to where the Horse Creek greenway starts.  I rode the Horse Creek greenway to where it ends, at the bicycle bridge over I440 near Wade Avenue.  

Then I rode across the bicycle bridge over I440 and on up to the North Carolina Art Museum.  I followed the bike paths around the art museum to Blue Ridge Road and took Blue Ridge Road back down the hill to Crabtree Valley Mall area.

I then rejoined the greenway and followed it up Crabtree Creek to its end where I had my banana a drink of waster and started back down the greenway.  I followed the greenway back to where Crabtree Creek and Lead Mine Creek come together and headed down the greenway toward I440.  Instead of going back to Yadkin Drive I decided to climb the hill up to North Hills Park, and extraordinarily steep climb.  They had just finished repaving the greenway up that hill and part of the asphalt was already starting to creep back down the hill.  Once out of North Hills Park I got back on Davidson Street and was only two blocks from home.

Here are some pictures I took along the way:

At the Shelly Lake dam.

Shelly Lake Dam

Crossing the bike bridge over I440

NC Art Museum Grounds

NC Art Museum Grounds

NC Art Museum Grounds

At northern most point of Crabtree Creek Trail

Tuesday, September 17, 2013

2013 CDC Resistant Bacteria 'Threat Report'

This note is not just about drug resistant bacteria but equally applies to many behaviors that humans have and continut to be engaged in.

Here is the report: "".

From what I've read antibiotics do something called 'forced evolution' of the bacteria.  All the 'easy' copies of the particular bacteria are wiped out by the drug leaving only the few resistant cells.  These cells may not be particularly suited to survive normal 'non-forced' natural selection but are artificially selected in favor of by the antibiotic.  

The unintended consequence of an antibiotic is to create antibiotic resistant bacteria.

Not only are humans treated by antibiotics but also our food animals are being treated.  I can imagine that the same unintended consequence will emerge among the bacteria we treat our animals for.

In the long run only a decrease in human population to sustainable levels that are in balance with the rest of the biosphere will 'fix' this.  

The best way to decrease the population is to raise the standard of living among all humans and basically eliminating the conditions that keep the poorest countries poor, the decline in the population of the US/Canada and Western Europe shows that this works.  

The 'bad-news' is that we live on a planet with finite resources and until and unless we mend our unsustainable ways we will, in pretty short order, correct ourselves out of existence.  

Nature (natural selection) doses not give a hoot about how fancy humans are and instead treats us just like any other organism:   If we insist on behaving like an opportunistic bloom we will crash just like all opportunistic blooms do.

Saturday, September 14, 2013

Shouting In Anger

A Hindu saint who was visiting river Ganges to take bath found a group of family members on the banks, shouting in anger at each other. He turned to his disciples smiled and asked,

'Why do people shout in anger shout at each other?'

Disciples thought for a while, one of them said, 'Because we lose our calm, we shout.'

'But, why should you shout when the other person is just next to you? You can as well tell him what you have to say in a soft manner,' asked the saint.

Disciples gave some other answers but none satisfied the other disciples. Finally the saint explained:

'When two people are angry at each other, their hearts distance a lot. To cover that distance they must shout to be able to hear each other. The angrier they are, the stronger they will have to shout to hear each other to cover that great distance.

'What happens when two people fall in love? They don't shout at each other, but talk softly, because their hearts are very close. The distance between them is either nonexistent or very small.'

The saint continued. 'When they love each other even more, what happens? They do not speak, only whisper and they get even closer to each other in their love. Finally they even need not whisper, they only look at each other and that's all. That is how close two people are when they love each other.'

He looked at his disciples and said,

'So when you argue do not let your hearts get distant, Do not say words that distance each other more, Or else there will come a day when the distance is so great that you will not find the path to return.'

Friday, September 13, 2013

Distance Between Points In Five Dimensions

Distance Between Points In Five Dimensions

You can compute the distance between points in one dimension by just subtracting their coordinates and taking the absolute value of the result.  Here is the formula for the distance between two points 'a' and 'b' on a line.

$$distance( a,b ) = \sqrt{ (a-b)^2 }$$

This formula generalizes to multiple dimensions.  In two dimensions it is the famous Pythagorean Theorem if you think of a line connecting the two points as the hypotenuse of a right triangle.  Here is the formula for the distance between two points in the plane:

$$distance\left( \left( { a }_{ 1 },{ a }_{ 2 } \right) ,\left( { b }_{ 1 },{ b }_{ 2 } \right) \right) \quad =\quad \sqrt { { \left( { a }_{ 1 }-{ b }_{ 1 } \right) }^{ 2 }+{ { \left( { a }_{ 2 }-{ b }_{ 2 } \right) } }^{ 2 } } $$

For purposes of going beyond two dimensions I am going to drop the square root and instead write it as distance squared. This is the general formula that we get:

$${ d }^{ 2 }\left( \left( { a }_{ 1 },a_{ 2 },\quad ...\quad a_{ n } \right) ,\left( { b }_{ 1 },b_{ 2 },\quad ...\quad b_{ n } \right) \right) \quad =\quad \sum _{ i=1 }^{ n }{ { \left( { a }_{ i }-b_{ i } \right) }^{ 2 } } $$

The above formula is just the sum of the differences between the individual coordinats squared.

On to five dimensions:  

Suppose you and your friend each pick five numbers at random.  Also suppose once you pick a number you may not pick it again.  Additionally suppose that you do not pay attention to the order that the numbers were picked.  

One way to make sense of far apart the two picks are is to think of each group of five numbers as a "5-Tuple" or a point in five dimensional space and then figure out how far apart the two points are.  

There is a problem with this idea if you did not pay attention to the order that the numbers were picked.  To see this consider the two '5-Tuples' (1,2,3,4,5) and (4,2,3,4,5).  These are different points in five dimensional space and their distance apart depens on the order you assign the numbers from the set {1,2,3,4,5}.

One way to deal with this is to consider all the possible choices for the value of the 5-Tuple.  This amounts to all the permutations of five objects.  There are 120 such values.  To figure out how far apart the two picks are you could consider pairing up each of the 120 different values of one of the picks with each of the 120 different values of the other pick.  This gives 120x120 or 14400 different pairs.  If you add all these up and divide by 14400 you get the average distance between any two pairs of 5-Tuples.

So here is a python program that will compute this.  In this program I call one of the 5-Tuples the "drawList" and the other 5-Tuple the "pickList".  Also you need to include the library named 'itertools' in order to get the function that creates a list of the various permuatations of a list.

Don't Forget To "import itertools"
And here are the results when the three different pairs of 5-Tuples are input.  You can see the values in the "__main__" proedure of hte program.

You could also take the square roots of these numbers to see numbers that are the same scale as the original values.

Saturday, September 07, 2013

2013 MS 150 Bicycle Tour


Saturday, a beautiful day for a bike ride.  I averaged about 25KPH for 120K. I even met up with Evana from the Gym and we rode together to the lunch stop.  She was doing "The Century" so that was where I was on my own.  The new bike was like riding on a cloud.  It still take energy to move the pedals around but it is a very 'sweet' ride!

Here are the stats for Saturday and some pictures from Saturday:

 04:51 .... hh:mm Time rolling along the way
119.90 .... Kilometers traveled
 24.70 .... Kilometers Per Hour Average
 36.90 .... Kilometers Per Hour Max (some pace-line :)

Oh yes ... by the way ... it is not too late to make a contribution to this year's ride.  My online MS Society web page is If you do not want to do an online contribution then feel free to mail me a check made out to The National MS Society and I will turn it in.  My mailing address is:

Zach Cox 
708 Davidson Street
Raleigh, NC 27609

Saturday Morning Start

Saturday Morning Lunch Stop

Saturday Afternoon Rest Stop With PICKLES!

Saturday Afternoon Last Rest Stop

Saturday Afternoon At The End Of The Ride

Sunday was a beautiful day, just a bit warmer but not too much so.  Evelyn was not volunteering today so I drove myself over to the ride and was ready go by 7:30am, the ride started at 8:00am.  This day, as is usual for Sundays, there were plenty of pace-lines and I did hook up with one that was traveling around 33kph (20mph).  The result was that I got to the lunch stop at 10:30am and then after lunch found myself all alone on the course.  This was not too bad except for the intermittent head winds. Another bit was that I decided not to swap out my new bike seat and I did pay for that decision during the last third of today's ride.  Here are the stats for today and then some pictures.

 04:46 .... hh:mm Time rolling along the way
118.42 .... Kilometers traveled
 24.80 .... Kilometers Per Hour Average
 46.70 .... Kilometers Per Hour Max (down the off ramp :)