There are three types of physical transmission media used in communications, which include twisted pair cable, coaxial cable, and fiber optic cable. These different types of cables are typically used within buildings or placed underground between buildings. Physical transmission media is often used with Ethernet and LANs.
Twisted-Pair Cable:
One of the more frequently used transmission media fro network cabling and telephone systems. This cable consists of one or more twisted pair wires bundled together. Each of the twisted pair wires have two separate insulated copper wires that are twisted together. The wires are twisted together to in order to reduce noise.
Coaxial Cable:
Consists of a single copper wire surrounded by at least three layers. The first layer is an insulating material, then a woven braided metal, and finally a plastic outer coating. These cables are mainly used now a days for cable television network wiring, because it can be run over longer distances than twisted-pair cable.
Fiber-Optic Cable:
This cable consists of dozens or hundreds of thin strands of glass or plastic that use light to transmit the signals.Each strand is called an optical fiber, and is as thin as a human hair. inside each fiber optic cable there is an insulating glass cladding and a protective coating surrounding each optical fiber. Advantages of fiber optic cables is there capability of carrying a significant more amount of signals than wire cables, faster data transmission, less susceptible to noise from other devices, better security for signals during transmission, and smaller size. Disadvantages include more expensive than the other two cables, and can be difficult to install and modify.
http://www.cs.virginia.edu/~zaher/classes/CS457/lectures/physical.pdf
This link shows examples of the three types of cables and what they consists of, and also how they are typically used.
Sunday, April 17, 2011
Sunday, April 10, 2011
Secure Email Project
http://www.free-press-release.com/news-if-anna-chapman-had-used-opolis-secure-mail-1280128968.html
http://www.free-press-release.com/news/200907/1249085516.html
In the first article an american spy got arrested for emails that she had sent, if she would have used a secure email her emails would not have been as easily detected. The second article explains how doctors and patients use secure email in order to keep information confidential.
Sunday, April 3, 2011
Avatar
The experience was a lot of fun and interesting. It was cool trying to make the avatar resemble me as much as I could.
Sunday, March 27, 2011
Tutorial 3: Searching the Web
The internet is a worldwide resource of information and one of the main reasons people use the web is in order to find specific information, such as text, pictures, music, and video. In order to locate this information on the web we use search tools. There are two types of search tools, which are search engines and subject directories.
Search Engines:
Search engines are helpful in locating information in which you don't know the exact web address or are not looking for a specific web site. There are thousands of different search engines available for use. Some search engines will search all types of information, and others you can specify what type of information you want, such as images, videos, audio, news, maps, people or business, and blogs. When using a search engine you enter a word or phrase that is called the search text, and it describes the type of item you want to find. Search engines usually respond with thousands of results, depending on the type of search and how broad or specific your search is. Some search results link straight to web pages or articles, well others results are media. Many times you will find that items that appear from your search results have little or no purpose to what you are actually seeking. You can eliminate this by carefully entering search texts that will limit the search. In this next link is a great example of ways you can make you search text in the search engine Google more limited. http://www.google.com/support/websearch/bin/answer.py?answer=136861
The results of a search are more commonly called hits, and each hit in the list is linked to the associated web site or web page, that was returned from your search. Most search engines use a program called a spider. This program builds and maintains lists of words found on web sites. When you enter your search, the search engine scans the prebuilt list for hits.
Subject Directories:
A subject directory provides a categorized list of links arranged by a subject. When using this type of search tool you select a particular topic, then by clicking links at different levels you go from general to more specific. Once you click on one category link the subject directory displays a list of subcategory links, from which you then again choose subcategory links. You continue doing this until you have reached a list of web pages about your desired topic. A major disadvantage factor about subject directories is that users have a difficult time choosing the right category they want as they move through the menus of links.
Sources:
< Picture created by Ethan Ashurst in Paint, Copyright 2011 >
< Gary B. Shelly and Misty E. Vermaat. Discovering Computers 2010. ch.2. pgs. 85-88 >
Search Engines:
Search engines are helpful in locating information in which you don't know the exact web address or are not looking for a specific web site. There are thousands of different search engines available for use. Some search engines will search all types of information, and others you can specify what type of information you want, such as images, videos, audio, news, maps, people or business, and blogs. When using a search engine you enter a word or phrase that is called the search text, and it describes the type of item you want to find. Search engines usually respond with thousands of results, depending on the type of search and how broad or specific your search is. Some search results link straight to web pages or articles, well others results are media. Many times you will find that items that appear from your search results have little or no purpose to what you are actually seeking. You can eliminate this by carefully entering search texts that will limit the search. In this next link is a great example of ways you can make you search text in the search engine Google more limited. http://www.google.com/support/websearch/bin/answer.py?answer=136861
The results of a search are more commonly called hits, and each hit in the list is linked to the associated web site or web page, that was returned from your search. Most search engines use a program called a spider. This program builds and maintains lists of words found on web sites. When you enter your search, the search engine scans the prebuilt list for hits.
Subject Directories:
A subject directory provides a categorized list of links arranged by a subject. When using this type of search tool you select a particular topic, then by clicking links at different levels you go from general to more specific. Once you click on one category link the subject directory displays a list of subcategory links, from which you then again choose subcategory links. You continue doing this until you have reached a list of web pages about your desired topic. A major disadvantage factor about subject directories is that users have a difficult time choosing the right category they want as they move through the menus of links.
Sources:
< Picture created by Ethan Ashurst in Paint, Copyright 2011 >
< Gary B. Shelly and Misty E. Vermaat. Discovering Computers 2010. ch.2. pgs. 85-88 >
Saturday, March 26, 2011
Database Project
In the database project I learned ways of using Microsoft Access. I have never used it before so it was all new to me. I learned how to create tables, Queries, Forms, and Reports in Microsoft Access. I also learned how to import data into access and how to format and edit the data. This Project gave me a better understand of how a database can be very useful.
One way I believe you could enhance the functionality of the database would be to create a query with age groups so that it would enable you to see what age group your gym most likely targets. I believe by doing this it would give the gym owner a better understanding of what age group they should target. If you set it up so it showed different age groups and also out of those age groups which had the most amount of end dates this would also be some helpful information. That's one way I believe you could effectively enhance this database.
One way I believe you could enhance the functionality of the database would be to create a query with age groups so that it would enable you to see what age group your gym most likely targets. I believe by doing this it would give the gym owner a better understanding of what age group they should target. If you set it up so it showed different age groups and also out of those age groups which had the most amount of end dates this would also be some helpful information. That's one way I believe you could effectively enhance this database.
Sunday, March 6, 2011
Web 2.0 Presentation
http://www.youtube.com/watch?v=uoO9gktdthM
In my presentation I used logical flow by explaining what the company does, how they use research to improve there company, what there strategy is after the research, how they have improved there company to achieve there strategy, then finally how they have completed and continue to improve there goals. It could be improved by maybe organizing the information, so it is more user friendly and easier to understand. I feel that I answered most questions that would explain the concept. There could be points in the presentation were you might have more in depth questions, but giving you all the little details would make the presentation long and boring and probably more confusing. I tried making the first two slides more interesting and general in order to grab attention quickly. I added a diagram in the second slide to make it easier to understand. I didn't ask many questions because I didn't feel that many people would know much about the company Zurich, so I mainly just explained what the company was all about. I tried to clearly and precisely explain the concept in order for the viewer to understand what I was trying to say. Any claims I made were believable and were backed up by facts. By making the slides simple and easy to understand I feel that it avoided any clutter and by not adding to many pictures to one slide. I attempted to make the slides very easy to read so the viewer would not be trying to read my slides and would listen to what I was saying. Also I didn't show everything on the slide at once, I put the information up as I was saying it.
By critiquing someone else's presentation it helped me to be able to critique my presentation better. Also it also gave me new ideas and ways to better my presentation. I learned different techniques of doing things that I didn't think of doing before and it also taught me some things that are not good to do. Not only did it teach me new and better ways of doing things, it also helped me better understand things that you should avoid doing.
Doing this project has taught me new ways of using web 2.0. Many of the tools you had to use to create this project were new to me and now I am more familiar with them. This project will be a big help when in the business world. I will now know how to create a better and more effective presentation and by being able to do this may help me achieve goals I may have within a company. Also by having this knowledge will make me more valuable to a business.
In my presentation I used logical flow by explaining what the company does, how they use research to improve there company, what there strategy is after the research, how they have improved there company to achieve there strategy, then finally how they have completed and continue to improve there goals. It could be improved by maybe organizing the information, so it is more user friendly and easier to understand. I feel that I answered most questions that would explain the concept. There could be points in the presentation were you might have more in depth questions, but giving you all the little details would make the presentation long and boring and probably more confusing. I tried making the first two slides more interesting and general in order to grab attention quickly. I added a diagram in the second slide to make it easier to understand. I didn't ask many questions because I didn't feel that many people would know much about the company Zurich, so I mainly just explained what the company was all about. I tried to clearly and precisely explain the concept in order for the viewer to understand what I was trying to say. Any claims I made were believable and were backed up by facts. By making the slides simple and easy to understand I feel that it avoided any clutter and by not adding to many pictures to one slide. I attempted to make the slides very easy to read so the viewer would not be trying to read my slides and would listen to what I was saying. Also I didn't show everything on the slide at once, I put the information up as I was saying it.
By critiquing someone else's presentation it helped me to be able to critique my presentation better. Also it also gave me new ideas and ways to better my presentation. I learned different techniques of doing things that I didn't think of doing before and it also taught me some things that are not good to do. Not only did it teach me new and better ways of doing things, it also helped me better understand things that you should avoid doing.
Doing this project has taught me new ways of using web 2.0. Many of the tools you had to use to create this project were new to me and now I am more familiar with them. This project will be a big help when in the business world. I will now know how to create a better and more effective presentation and by being able to do this may help me achieve goals I may have within a company. Also by having this knowledge will make me more valuable to a business.
Sunday, February 20, 2011
Tutorial 2: Audio Multimedia
Key concepts:
Digital audio is a bunch of number values that are used to interpret sound waves at different points in time. The value is digitized, with digital audio you can copy the numeric values over and over again without ever losing any quality. With analog data you cannot copy it over and over again without losing quality, to prevent that from happening there is a software called CODEC. It codes and decodes analog data and digital audio. First it takes the analog sound and coverts its to a series of numbers which is digital audio, then it decodes it and takes the digital information and converts it back to analog audio, which you are then able to listen to. In order to play the audio back you have to have the same CODEC software which was used in the first place. Compression is another concept to multimedia audio. For multimedia audio you use a lossy compression type, which sacrifices file quality for the sake of compression, but can sound just as good to the human ear as the uncompressed version, but at a 7th or 10th of the size. With compression you run into two options quality vs size. Typically, with music you want higher quality and less compression, but if it is simply a voice you can have much more compression without losing much quality.
Creating your own Audio:
In order to create your own audio you have to have some type of hardware to capture the audio and then a software program. The audio hardware used is microphones and audio adapters, this hardware gets attached to a line-in, mic jack, or USB port, which are all found on most every PC or laptop. The software used can be downloaded for free, or if more advanced software is required you can purchase it.
Digital audio is a bunch of number values that are used to interpret sound waves at different points in time. The value is digitized, with digital audio you can copy the numeric values over and over again without ever losing any quality. With analog data you cannot copy it over and over again without losing quality, to prevent that from happening there is a software called CODEC. It codes and decodes analog data and digital audio. First it takes the analog sound and coverts its to a series of numbers which is digital audio, then it decodes it and takes the digital information and converts it back to analog audio, which you are then able to listen to. In order to play the audio back you have to have the same CODEC software which was used in the first place. Compression is another concept to multimedia audio. For multimedia audio you use a lossy compression type, which sacrifices file quality for the sake of compression, but can sound just as good to the human ear as the uncompressed version, but at a 7th or 10th of the size. With compression you run into two options quality vs size. Typically, with music you want higher quality and less compression, but if it is simply a voice you can have much more compression without losing much quality.
Creating your own Audio:
In order to create your own audio you have to have some type of hardware to capture the audio and then a software program. The audio hardware used is microphones and audio adapters, this hardware gets attached to a line-in, mic jack, or USB port, which are all found on most every PC or laptop. The software used can be downloaded for free, or if more advanced software is required you can purchase it.
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