1. Decode this message by converting it from binary to ASCII: 1000001 1110000 1110000 0100000 1001001 1101110 1110110 1100101 1101110 1110100 1101111 1110010 0100000 1010010 1001111 1000011 1001011 1010011 0100001. When the message is decoded it reads "App Inventor ROCKS!"
2. Describe what it means to say that JPEG is a lossy compression technique and whether or not it affects the quality of camera pictures.minuscule It is a lossy technique because some of the information gets lost. However, it does not affect the quality of photos because the difference is too to notice.
3. Give a specific example of a binary sequence that can represent more than one type of data -- e.g., a number, a color, a character -- and describe how to interpret its different values. The binary sequence 111111 represents 63 in decimal, a "?" symbol in ASCII, and is the color white, represented as #ffffff.
3.6 Error Detection Reflections
1. (POGIL) Describe an algorithm for identifying the card that was flipped? In order to identify the flipped card you have to find the column with the even number of flipped cards and the row with the even number of flipped cards. Wherever the row and column intersect is the location of the flipped card.
2. (POGIL)The card "trick" shows that it is always possible to identify the card that was flipped as long as only one card was flipped. Would it be possible always to determine if an error occurred if two cards were flipped? Explain. It is possible to identify it if two cards are flipped, however the flipped cards must not be in the same column or row. If two cards are flipped in the same column, the column will look as though it has not been changed, only the row will look messed up, making it impossible to figure out what has been flipped. If they are not in the same column or row then you can find both of the flipped cards, you just have to repeat the process of finding one flipped card twice.
3.7 Parity Error Checking Reflections
1. Explain how the error card trick from Lesson 3.6 uses a parity scheme. Was it an even or odd parity scheme? It was an odd parity scheme because if there was an even number of green cardss in a row or column, a green card would be added at the end and if it was an odd number of green cards, it would add a black (off) card to the end.
2. What are some of the limitations of using parity bits for error detection? The issues are that you cannot locate multiple errors, or it can but it's hard to tell which bits were transmitted incorrectly, and you have to transmit extra data. 3. Another type of error detection is a check sum. Research what a check sum is and then describe it in your own words. Can a check sum identify where an error occurs? Checksum is an error detection system that adds a digit that represents the sum of the digits being stored or transmitted. The data can later be checked for errors if the digits do not add up. Checksum cannot always identify the error, but some forms can, such as position-dependent checksum, which also accounts for the value and location of each digit.
4. Explain in your own words the difference between error detection and error correction. Describe how the error correction process used in the video above allows the computer to fix errors. Error detection finds errors while error correction finds errors and fixes them. The error correction process in the video encoded a four bit sequence into a seven bit sequence by adding three parity digits to it.
3.10 Map Tour Tutorial Reflections
1. What is the list picker component? How was it used in this app? The list picker component is used to display a list of option and have the user select one of the options from the list. In this app, it was used to allow the user to choose from 3 destinations in Paris, the Louvre, the Cathedral of Notre Dame, and the Eiffel Tower.
2. What is the activity starter component? How was it used in this app? An activity starter component allows other apps installed on your device to be opened from one app. Pre-installed apps, downloaded apps, and even apps made from App Inventor can be opened using the activity starter
3. If you were on a real tour, would the Map Tour app be a good app to have and use? Why or why not? On a real tour, this version of the Map Tour app would not be very useful. It is limited to only 3 locations in Paris, and does not even offer directions. You would be much better off just using Google Maps or a travel app.