Sunday, October 23, 2016

Critical Thinking

Critical thinking is "the objective analysis and evaluation of an issue in order to form a judgment."
Unfortunately many people don't typically demonstrate the capability of critical thinking.

What is the main obstacle to critical thinking? Mental laziness.

How so?

Most recent example is the Rolling Stone's sensational but false story about University of Virginia "Rape on Campus"  based on fabricated story from the "victim". Despite many holes in the published story, tens of thousands of people marched to protest UVA administration's handling of the case. The reasons for the protesters to march include: those who read the story accepted the story as "fact" without thinking, many more did not even read the story - their outrage was based on reading the headline in the news or just hearsay!!

Either way, they blindly trusted "authorities", in this case "Rolling Stone", more generally it could be news media/network news, government officials, celebrities, technical experts or even what is stated on Wikipedia. They accept what is stated by "authorities" as facts, truth, without thinking, because the "authorities" thought about it already.

How can one be a critical thinker? Have a reasonable dose of doubt, be analytical - understand what, ask why, know how.

In technical world, even if a conclusion was obtained by a reputable source, a good scientist or engineer will not blindly accept the conclusion as truth, they trust the source but verify the conclusion.

Years ago, when I was in graduate school, my professor came up a clever algorithm to perform a very difficult numerical computation. But its implementation somehow only worked for a special case, but not generally. The professor believed that there were bugs in the his computer program. His first student worked on it for half a year without fixing the problem. He asked me to look into it.

I reviewed his algorithm, re derived all formulas in the algorithm in half day. I found a mistake in his formulas. The program was fixed the next day!!

From half year to half day - that was the difference critical thinking made!

Lack of critical thinking in technical world can lead to wasted time and wasted resource. Lack of critical thinking in societal issues could allow falseness be treated as truth, impact our lives.

Most people have the capability of critical thinking. Please apply your critical thinking capability daily!

Saturday, October 15, 2016

Tracking Fitness Exercise

It was a beautiful, sunny, cool and crisp Saturday morning last week. Migrating birds flying in southeast direction is another indication of change of season. Instead of our usual weekends' morning walk around the community, we decided to run to the local library and walk back.
migrating birds flying south 
We exited the community and ran east along Hedgecox road, turned at Independence parkway, continued to run to reach the library, which was about 1.5 miles away from our house. Instead of walking to return along the same route, we continued into the neighborhood behind the library.

It was a quiet morning, we did not see anybody in the street or on the sidewalk until we got to the pond behind the library - a man was walking his dogs, a lady was jogging along the pond, a raft of ducks in the pond and a grey heron was standing by the pond which flew to other side of the pond as we ran by.

Since I turned on the tracking app on my phone, I knew how much time and how long I ran, I decided to continue running until I reached 2 mile distance. It turned out that  the loop we ran/walk was just short of 3 miles when we stood in front our house, so I continued to walk a lap around the block. In the end I ran/walked 3.33 miles in 47 minutes, with average speed  at 4.2 mph.

our route this morning
Tracking my exercise is another thing Lily has been encourage me to do. Just like TED talk, I resisted the idea initially. I thought that all I needed to know was approximately how long I walked/ran, and how much time I spent on it, no need to be precise....and previously my iPhone consumed a lot of power while a tracking app was turned on.

When I changed cell pone recently to S7, she helped to install the app S Health, which consumes little power and uses only GPS for tracking. I started using the app all day. I tracked my lunch time walk around campus at work - I knew that it took me 20 minutes for an 1 mile walk - and the app of course is more accurate, but my estimation is within 5% of the app. Even so it was still great to get an bird's eye view of my track, and exact time spent, calorie burned....

Looking at that morning's record, she encouraged me to try 5k! I will give it a try. 

The next day I mapped a 3 mile track within our community, which is nearly the same length as the previous day's , and my estimation was again very close to the GPS calculation.

Tracking exercise is not critical to our fitness, but it does help to keep us on target quantitatively and the data may motivate us to reach the target. 

Saturday, October 8, 2016

Fixing Air Conditioner in my Van

I am not a car guy, I don't even change oils for my cars, but I fixed my van's AC problem!

What happened?

Last week it was our turn to drive for carpool to early morning marching band practices. On Wednesday morning, while waiting for the last boy to arrive, I noticed that the AC vents at driver side blew warm air even though I did not turn AC on.

That afternoon happened to be hot. When I started the van to go home, I turned on AC for cooling. I felt the blow of warm air from driver side vents again! It was hot, so I gave AC a few minutes to really work. The air got hotter as I drove. It was so hot that I had to open van's windows.

 I checked the air from passenger side vents, it was cool  as it was supposed to be. Apparently AC was working, something else was not. My snap judgement was 1) hoses leaked, 2) some valves malfunctioned, 3) on board computer malfunction.

Find root cause

I drove to the car service shop near my house and talked to the service adviser about the issue. I described to him what happened, withholding my own diagnosis, and asked him about the potential reasons. He gave me a check list answers to cover everything. So I told him my own diagnosis to try to narrow down the potential reasons, and emphasized that passenger side vents blew normal cold air, and driver side vent blew erroneous hot air. He double checked my van's make/model, and told me that the van has a separate valve for each side of the vents, it was likely that the valve control hot air intake on driver side stuck in open position.

I turned on and off the van a couple times already, it was not likely to be a on-board computer issue. I am pretty sure that the stuck valve was the root cause. I made a reservation for Saturday to fix the AC.

My Fix

I thought about the situation a bit after I parked the car in the garage, still sitting on the driver's seat:

How do I fix the stuck valve problem physically? I need to wiggle it back and forth.
How do I wiggle the valve without opening the hood? I change AC temperature on the dash board.

I changed the temperature up and down by 10 degrees, not seemed to work. I adjusted temperature setting to both extremes a few times ..... and then set it to cold, the cold air started to blow from driver side vents. I fixed the AC problem without getting my hands dirty!

Be observant, be curious and connecting dots to seek solutions. "Be observant" leads to identification of problems, "Be curious" helps to find root cause of the problems, "Connecting dots" will give you a good solution in short time.  This is my default approach to all aspects of life, be it technical or non-technical. This time I used it to fix the van's AC problem.

Of course these all happened subconsciously - I dissected the process to write this post -:) because it was a very satisfying experience!

The only guilt I had was that I forgot to cancel my reservation to fix the AC at the car service.

Note  - other similar examples in this blog include  fixing Kenmore Washing Machine Lid Switch, Setting Thermostat for Central AC in a Two Story House.

Saturday, October 1, 2016

TED Talk

Lily has been a big fan of TED talk for sometime. She recommended it to me for a number of times. But I was not quite as interested in it as she was. One reason was that,  especially for topics on life, I thought I know what they talk about already.

Recently I had an awakening - I want to read more on various topics, to listen to others' perspectives, even on topics I have a strong opinion or I am very good at. I try to achieve the goal that I will complete reading or listening even if I am opposed to the author's position, or the speaker's opinion, as long as I am interested in the subject.

TED talk, which is typically 10 ~ 15 minutes long, is a good place start this exercise. I signed on to receive daily alert from In the past two weeks I listened to about 10 talks,  Through some of these talks I was exposed to some new ideas and concepts: what is blockchain, why artificial intelligence could be a threat to humankind, the top factor that determine a start-up's success. I have my own opinions on many of the subjects - but upon listening to the whole talks, I found that looking at the same thing from a different perspective could be very interesting and enlightening, some facts on the subjects could be very fascinating and informative - how to make vote fun again was a timely topic; technology has not changed love - a no brainer to me, but the speaker gave some interesting data to back it up; harnessing nature's power via biomimics is a common subject in academic research, but put it on a commercial scale is totally another thing; the career advice on focus on development of business acumen ....

What impressed me the most among those talks I listened to are the following three:

Dare to disagree

It is not only about dare to disagree, it is also about the capacity to accept and welcome disagreement so that we can think deeper, look wider.

Why you should talk to a stranger

I was quite suspicious of the speaker's motive at the beginning, but in the end I was convinced that we should "embrace those fleeting but profoundly beautiful moments of genuine connection" occasionally.

What enduring love looks like

This is another one I thought that I could have skipped at the beginning because I thought that the speakers were off topic. However the first half set-up made the ending very powerful and convincing.