The mode of operation and the associated tools change with the Order of Magnitude.
There is a change in an order of magnitude when a number (or measure) is multiplied by ten.
The following are examples of the mode of transportation with the change in order of magnitude. An average person can walk 4+ mph (miles per hour). An average car can be driven 40+ mph. An air plane can be flown 400+ mph.
Modern Physics evolved from Classical Physics to handle the vast range of speed and size.
Newtonian Mechanics holds when objects move at a relatively low speed (compared to that of light).
Relativity comes into play when objects move at a speed closer to that of light.
The size of an object can span several orders of magnitude.
[Per Dr. Kyaw Tint] When they become small, Quantum Mechanics can only describe their behaviors.
PDP-8 had limitations, but it was affordable to universities and users.
UCC bought PDP11/70.
Gordon Bell was the architect of VAX.
Microsoft bought a part of DEC.
PDP11/70
Khin Maung Zaw wrote :
It’s kind of sad that DEC failed to keep up with their lead beyond PDP.
I don’t know why Ken Olsen was pushed out, my limited understanding was that he was not high on Unix (he had been attributed to calling Unix a ‘snake oil’), for some reason his attempts to push VAX/VMS didn’t take off as he might have liked. I’ve read it somewhere that he didn’t get much support within DEC on the VAX/VMS endeavor.
At the time, there was a talented group of DEC engineers in Seattle area (across the lake from Seattle, matter of fact we here called East Side – Bellevue/Redmond). If I recall correctly, the first Microsoft Data Center at Canyon Park, several miles north of Redmond, was ran by DEC folks in the late 80s, early 90s.
A brilliant OS architect, Dave Cutler, part of a triumvirate led DEC’s Star project, a virtual 32-bit extension on PDP 11/70. Star and its cousin Starlet became precursor to VAX/VMS among others. The triumvirate were working at the DECWEST facilities in Bellevue, next to the city of Redmond.
Around late 1980s, some events – of which I’m no clue whatsoever, Canyon Park Data Center staff as well as many of the DECWEST team became part of Microsoft.
As the saying goes, “The Rest Is History”. Dave Cutler and his team led the development of Windows NT, New Technology” and beyond. Some folks attributed Billg who manged to extract most of the DEC VAX team into MSFT.
[A titbit on VAX and NT] Mark Russinovich, received his PhD from Carnegie Mellon in 1994, wrote series of articles in the Windows magazine, comparing the deep down internals of vms and NT. He even discovered the names of the internal variables have the identical names between them.
He co-founded a company called “Winternals”, developed a set of Windows tools which quickly became a Swiss knife for every Windows engineer. Needless to say, Microsoft bought his company, the tools became part of Windows. Mark became Technical Fellow, and now he is the CTO of Azure.
It is used by dishonest people to cheat unwary folks.
Nigerian Scam
It is one of the oldest scams.
Typically, one gets an e-mail supposedly from a friend asking for help (e.g. need money desperately to buy a return ticket home) and to follow instructions (e.g. transfer money) to get him out of the trouble. There is a promise to repay the debt.
Some get emotional & forget logic and the importance of verifying (double checking). They rush off to write a check.
Why Scam?
It does not need much effort to scam.
Even if a tiny fraction of the recipients fall into a scam, the scammers get rich.
Even if they are caught (possibly after a long time), the resources needed to get back the money (extradition, law suit) are too much and not cost-effective.
Variations
Someone claiming that he / she had inherited millions of dollars
A company claiming that you had won a big prize
Some scenario suggesting “It’s too good to be true”.
Scammers
Some are sloppy copy cats (with typos and errors in the message). If you are careful, you can easily confirm their scams.
Some simply change the settings (Edinburgh, Scotland instead of Nigeria). It’s not difficult to confirm such scams.
Some may use malware to take over computers and send scams from the hacked account.
Right actions to beat scams
Call your friend and his/her family to verify
Use nick names or sensitive information to check if the sender is a hacker
Some people are superstitious and associate Bad Luck with specific signs and events (e.g Solar & Lunar Eclipses).
Correlation
In Probability and Statistics, one has to determine if two variables have positive, negative or zero correlation.
Two variables are said to be positively correlated if both go up and down together.
Two variations are said to be negatively correlated if one goes up when the other goes down (and vice versa).
Two variables are said to be zero (no) correlation, if there is no significant trend.
Confusion
Some confuse Correlation with Causation.
Correlated variables may or may not be related as “Cause and Effect”.
For example, we hear, “My friend has lung cancer. He does not smoke.”
Does Smoking cause Lung Cancer?
The early experiments show some correlation between Heavy Smoking and Lung Cancer.
There are several parameters in Smoking
cigar, cigarette, e-cigarette, cheroot
frequency
quantity
deep inhalation
second hand smoke
Superstition about Eclipse
Solar and Lunar Eclipses occur every year. There are Total and Partial Eclipses. We cannot see all eclipses from a place. Some occur in places we cannot see.
Some are superstitious. They fear when there are Eclipses.
Eclipses are natural phenomena. They do not cause bad events to happen.
Sholes invented the mechanical typewriter. In order to prevent two keys stuck after hitting them rapidly, he designed the QWERTY layout.
Business schools and companies trained “touch typing” with the QWERTY keyboards.
Ergonomics
In the English alphabet, e is the most frequently used vowel, and t is the most frequently used consonant. To hit them, a touch typist has to move a left finger.
This led to claims that the QWERTY keyboard is not ergonomic; not suitable for efficient typing and It could cause tendonitis and similar medical problems.
Computers (desk tops laptops, pads, …) continue to use QWERTY because most people do not want to change their habits, and retraining is costly.
Numerous attempts to replace QWERTY were not successful.
Many computer users are not touch typists; some use the “hunt and peck” method using two fingers. They do not care about the ergonomics of the keyboard.
A few use ergonomic keyboards either with QWERTY layout with two sections (e.g. laid out in V-shape) or with non-QWERTY layout (e.g. Dvorak)
U Khin Maung Zaw(EC76) wrote :
In the early days, one of my leads really like Dvorak keyboard and used it on his desktops. One day we had an issue with one of the servers, and needed to logon to it to troubleshoot the root cause. [This was before the advent of the remote access.]
Even though we had the admin password, no one could logon to it, and the lead was on vacation for couple of weeks. We decided not to rebuild the server as it had some unique applications running on it and the issue was livable, waiting for him to come back. [He was the last person to logon to that server, so we assume he might have changed the password without telling the team.]
When he came back to work, we told him about the server, naturally he logged on to it to investigate. We asked him what the new password was, he denied he changed it at all.
Then we discovered he changed the keyboard to Dvorak while using it but did not switch it back.
The directive was issued across the board not to switch the keyboards on any servers, across all company data centers.
Approach starts with the Design Requirements and then decide on the intermediate and final steps to get the design implemented.
Used some software projects.
May also be used in the writing of a book. One first decides on the structure and contents.
Bottom Up
Used when one has a set of bases, foundations and libraries.
Building blocks are then assembled and refined to develop a desired product.
May also be used in the writing of a book. If one has written posts for a long time, they may be used as a basis for further development into an e-book or printed book.
Middle Out
Approach is used to develop several software.
Uses a hybrid (part Top Down and part Bottom Up). It is important to make sure that the two parts meet properly.
In the context of publishing, a group of writers and editors can come up with a Design for the book, use existing material as much as possible and try to bridge the gap with new material.
If a lesser weighted symbol appears to the left of a larger weighted symbol, the lower value is subtracted from the higher value. Examples : IV (5 -1 = 4), XC (100 – 10 = 90)
If a lesser weighted symbol appears to the right of a larger weighted symbol, the lower value to added to the higher value. Examples : VII (5 + 1 + 1 = 7), CXX (100 + 10 + 10 = 120)
Drawbacks
Difficult to perform arithmetic operations.
Not easy to read large Roman numbers. Movie companies supposedly use Roman numbers in their copyright dates so that the audience could not quickly figure out if a movie is too old.
Hindu-Arabic System
Digits
In the Decimal system, there are ten digits 1, 2, 3, 4, 5, 6, 7, 8, 9 and most importantly 0 (Zero).
“The Dawn of Nothing” emphasizes the introduction of Zero thereby allowing the positional system of representing numbers.
Advantages
It has several advantages over the Roman Number System.
Compact representation
Ease of performing arithmetic operations.
Number systems in Mathematics
Integers Positive, Zero, Negative
Real Numbers Positive, Zero, Negative
Complex Numbers Real Part and Imaginary Part
…
Bases and Usage
Base 10 : Decimal Most common
Base 2 : Binary Used in computers
Base 3 : Ternary
Base 4
Base 8 : Octal
Base 16 : Hexadecimal
Base 60 Angular and Time Measure Minutes & Seconds
Mixed Base Old British Measures e.g. Mile, Furlong, Yard, Foot, Inch
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