Positional vs. Non-Positional

The difference between the positional and non-positional number systems is simple. The positional system is based on exactly where the numbers are in the sequence of numbers; as opposed to non-positional number systems where the position of the number isn't a determining factor. An expamle of the non-positional system would be roman numerals.

Decimal to Binary

You need to take 529 and start dividing it by two, keeping track of the quotient and the remainder.

Decimal - Quotient -- Remainder ------- Binary
529 ----- 264 ------ 1 ------------------ 1
264 ----- 132 ------ 0 ----------------- 01
132 ----- 66 ------ 0 ---------------- 001
66 ------ 33 ------ 0 --------------- 0001
33 ------ 16 ------ 1 -------------- 10001
16 ------ 8 ------- 0 ------------- 010001
8 ------- 4 ------- 0 ------------ 0010001
4 ------- 2 ------- 0 ----------- 00010001
2 ------- 1 ------- 0 ---------- 000010001
1 ------- 0 ------- 1 --------- 1000010001

Therefore the binary number for 529 is 1000010001.

Binary to decimal

To convert 11001010 to a decimal number you need to align 11001010 with the powers of two starting at the right side. Always start on the right side and start with 2^0 and move upwards.

Example:

2^7 2^6 2^5 2^4 2^3 2^2 2^1 2^0
1 1 0 0 1 0 1 0

After this you need to figure out the total of the numbers with a 1 under them, add all of these together.

128+64+8+2 You get 202.

lab 5

Lab 5 Andy Clark's

The chapter, “Global Swarming,” is interesting and dealt with the comparisons and how people, animals, and computers follow different trends to combine systems of efficient life. Clark brings up "positive feedback" as an idea. It gives a positive reinforcement for an action. It is similar to how ants use pheromones to create paths to the closest food source. When the food source runs out, the path to the next closest food source will then have the most pheromones. The food is the reinforcement and is subconsciously a positive feedback. Toward the end of the chapter, Clark introduced the “TTT world” (things that think). I found this interesting, in that it appears that most every aspect of life is monitored and taken care of when needed. This was interesting to learn about how things would be if everything thought for itself.

Lab 4 Unix Commands

Unix commands:
1. One command that I learned and thought was really cool about the Unix commands was “finger.” When you type in finger and then a user name it brings up information about that person.
2. Another command that I find interesting is “cal.” If you type cal 2006 it brings up a calendar of the whole year. It is simple and convenient. On windows you have to click on the time in the corner to have it bring up the calendar.
3. The command “cd” allows you to move from one directory to another. . On windows, all you have to do is open a new application, but in Unix, you have to type “cd” and then the name of the directory. In dos, cd is the same as dir.
4. The “whoami” command lets you know who is logged in on the computer that you are on. In windows you can just click on start and it tells you who is logged on to the computer at that time.

Lab 4

“Modeling of the World” was good at describing the models for us. This also gave me a sense of what they can do for us. The basic principal discussed in the lecture was that the world is made up of many agents who become informed by signs about one thing or another. I think that as humans we would be far behind if we didn’t have signs in our everyday life to tell us what we need to know. Models provide several purposes including data analysis, control, interpretation, prediction and understanding key aspects. They can also help us understand many different things. Some models are used to explain different things for different situations, in the same way that signs are like representations. Models are helpful and we should learn how to make more use of the models that are given to us.