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Albert Einstein (1879-1955) "Make things as simple as possible and no simpler."
Science is the accumulation of observable data that conforms to the requirements of objectivity and reproducibility. Scientific experiments involve the manipulation of variables. The independent variable is the variable under investigation or being changed. The dependant variable is the variable which you are studying. The application of Scientific principles and computer problem solving are one and the same.
A caveat about the author: Hypocrisy does not necessarily negate the premise. The following steps make up the Scientific Method. These steps make up a method which may be used to logically solve problems in many other areas of life.
In science when testing/doing the experiment, it must be a controlled experiment. The scientist must contrast an "experimental group" with a "control group". This is not always practical or possible with computers, but certainly a good reason to own more than one computer. The two groups are treated EXACTLY alike except for the ONE variable being tested, the independent variable. Sometimes several experimental groups may be used. For example, in an experiment to test the effects of day length on plant flowering, one could compare normal, natural day length (the control group) to several variations (the experimental groups). 1. Independent variable is a variable in a functional relation whose value determines the value or values of other variables, as x in the relation y = 3x2. The independent variable is that which does not depend on what's going on with something else in the experiment--the variable over which you have control and manipulate, which you vary according to your plan (like, how much of a drug you give a patient, or how many ml of alcohol someone has consumed or how much ram is in a computer). 2. Dependant variable is a variable in a functional
relation whose value is determined by the values assumed by other variables in the
relation, as y in the relation y = 3x2. When doing an experiment, replication is important. Everything should be tried several times on several subjects. The experimenter gathers actual, quantitative data from the subjects. For example, it's not enough to say, "I'm going to see how the computer reacts in this situation." Rather, in that experiment, the scientist might have a list of certain behaviors, and record how often the computer exhibits each of those pre-defined behavior patterns. Data for each of the groups are then averaged and compared statistically. It's not enough to say that the average for group "X" was one thing and the average for group "Y" was another, so they were different or not. The scientist must also calculate the standard deviation or some other statistical analysis to document that any difference is statistically significant. Research is cumulative and progressive. Scientists build on the work of previous researchers, and one important part of any good research is to first do a literature review to find out what previous research has already been done in the field. To be continued
Meaning two. The principle behind digital computers. All input to the computer is converted into binary numbers made up of the two digits 0 and 1 (bits). For example, when you press the "A" key on your personal computer, the keyboard generates and transmits the number 01000001 to the computer's memory as a series of pulses. The 1 bits are transmitted as high voltage; the 0 bits are transmitted as low. The bits are stored as charged and uncharged memory cells in the computer. On magnetic disk and tape, the bits are stored as positively and negatively charged spots. Display screens and printers convert the binary numbers into visual characters. The electronic circuits that process these binary numbers are also binary in concept. They are made up of on/off switches (transistors) that are electrically opened and closed. The current flowing through one switch turns on (or off) another switch, and so on. These switches open and close in nanoseconds and Pico seconds (billionths and trillionths of a second). A computer's capability to do work is based on its storage capacity (memory and disk) and internal transmission speed. Greater storage capacities are achieved by making the memory cell or magnetic spot smaller. Faster transmission rates are achieved by shortening the time it takes to open and close the switch. In order to increase computer performance, we keep improving binary devices.
How Binary Numbers Work Binary numbers are actually simpler than decimal numbers as they use only the digits 0 and 1 instead of 0 through 9. In decimal, when you add 9 and 1, you get 10. But, if you break down the steps you find that by adding 9 and 1, what you get first is a result of 0 and a carry of 1. The carry of 1 is added to the digits in the next position on the left. In the following example, the carry becomes part of the answer since there are no other digits in that position. Kingston Ultimate Memory Guide - How Memory Works
carry--1 9 + 1 ____ 10 The following example adds 1 ten times in succession. Note that the binary method has more carries than the decimal method. In binary, 1 and 1 are 0 with a carry of 1.
Binary Decimal
0 0
+ 1 + 1 ____ ____ 1 1
+ 1 + 1 ____ ____ 10 2
+ 1 + 1 ____ ____ 11 3
+ 1 + 1 ____ ____ 100 4
+ 1 + 1 ____ ____ 101 5
+ 1 + 1 ____ ____ 110 6
+ 1 + 1 ____ ____ 111 7
+ 1 + 1 ____ ____ 1000 8
+ 1 + 1 ____ ____ 1001 9
+ 1 + 1 ____ ____ 1010 10 |