mydigitalworld

https://www.youtube.com/watch?v=3sUT1u4WMP4

After I watched the video, I found the thing that most surprised me is the existence of e-waste. In the past, I never think about that disposed of electronics would hurt the environment, because people use computers, phones or faxes every day, and these machines do not harm humans. However, now I know the waste electronic are not only polluting humans but also damaging the ecosystems. According to facts presented by the Electronics Takeback Coalition “Electronic scrap components, such as CPUs, contain potentially harmful components such as lead, cadmium, beryllium, or brominated flame retardants.” Additional components such as mercury and arsenic can also be present. All elements listed can have severe human impact through exposure. If these items aren’t handled correctly, they can cause organ damage, neurological damage, and severe illness not only in the workers that handle them directly but also within the communities of the developing countries where they are shipped. (https://www.rubiconglobal.com/blog-electronic-waste-problem/ ) Therefore, there are many components in electronics that is dangerous. If they are not recycled properly, then they will harm the air, water, and soil, which is called E-waste.

Also, the number of recycling is shocking. There are some E-waste facts people should think about: 1. in the U.S. alone, over 140 million cell phones are thrown into landfills every year. If all the cell phones were recycled, it would save enough energy to power 25,000households for one year. 2. The United States is No. 1 worldwide in terms of e-waste produced annually. Americans throw around 9.4 million tons of electronics every year. 3. Only 12.5% of e-waste is recycled. 5.E-waste represents 2% of America’s trash in landfills, but it equals 70% of overall toxic waste. (https://www.rubiconglobal.com/blog-electronic-waste-problem/) These facts show America is facing a big problem on recycling  E-waste, and they did not have practical solutions, the number of electronic productions is significant, but the recycled e-waste is relatively small.

So how to recycle the discarding electronic is the major problem. Temple Univesity has a department called Computer Recycling Center (CRC), it gathers surplus computer and electronic equipment from around the university, refurbishes that equipment if possible, redeploys the equipment where appropriate, donates any unwanted usable equipment and, where appropriate, disposes of unusable equipment in a secure manner. (https://its.temple.edu/lab/computer-recycling-center) And the CRC employs the 3 R’s hierarchy when handling material: Reduce, Reuse, Recycle.

Not only a university has an e-waste recycling center, a community always has a recycling center.  The amount of e-waste in a community is larger than a university’s, it means the process and classification is more sophisticated. There are several steps of e-waste recycling:

• 1. picking shed. When the e-waste items arrive at the recycling plants, the first step involves sorting all the items manually. Batteries are removed for quality check.
• 2. Disassembly. The e-waste items are taken apart to retrieve all the parts and then categorized into core materials and components. The dismantled items are then separated into various categories into parts that can be re-used or still continue the recycling processes.
• 3.First size reduction process. Items that cannot be dismantled efficiently are shredded together with the other dismantled parts to pieces less than 2 inches in diameter.
• 4. Second size reduction process. The finer e-waste particles are then evenly spread out through an automated shaking process on a conveyor belt. At this stage, any dust is extracted and discarded in a way that does not degrade the environmentally.
• 5. Over-band Magnet. At this step, over-band magnet is used to remove all the magnetic materials including steel and iron from the e-waste debris.
• 6. Non-metallic and metallic components separation. Copper, aluminum, and brass are separated from the debris to only leave behind non-metallic materials. The metals are either sold as raw materials or re-used for fresh manufacture.
• 7. Water Separation. One separated, all the materials retrieved can then be resold as raw materials for re-use. The products sold include plastic, glass, copper, iron, steel, shredded circuit boards, and valuable metal mix.(https://www.conserve-energy-future.com/e-waste-recycling-process.php)

However, in the process of recycling, workers should care about their healthy. As the video plays, there are many Chinese workers who do not do any protective measures, or even do not know the harm of their work. Some parts that are removed will cause damage to workers’ bodies.

In addition to protecting the ecological environment, the purpose of recycling waste is to save energy and reuse resources. There are several components can be reused: plastic, hard driver and batteries, et.c. All the plastic materials retrieved are sent to recyclers who use them to manufacture items such as fence posts, plastic sleepers, plastic trays, vineyard stakes, and equipment holders or insulators among other plastic products. Hard drives are shredded in whole and processed into aluminum ingots for use in automotive industry. Batteries are taken to specialized recyclers where they are hulled to take out plastic. The metals are smelted is specialized conditions to recover nickel, steel, cadmium and cobalt that are re-used for new battery production and fabrication of stainless steel. (https://www.conserve-energy-future.com/e-waste-recycling-process.php)

Also, E-waste recycling creates new jobs for professional recyclers and creates a second market for the recycled materials. The conductor in Temple recycling center is benefit from the E-waste recycling.

A transmission system is a system that transmits a signal from one place to another.

Packet switching is a digital network transmission process in which data is broken into suitably-sized pieces or blocks for fast and efficient transfer via different network devices. When a computer attempts to send a file to another computer, the file is broken into packets so that it can be sent across the network in the most efficient way. These packets are then routed by network devices to the destination. https://www.techopedia.com/definition/5603/packet-switching

Packet switching is efficient because it uses overall network bandwidth due to flexibility in routing the smaller packets over shared links. The network bandwidth refers to a volume of information per unit of time that a transmission medium can handle. What bandwidth means and how it applies to your own network can help you tweak your setup to get a faster internet connection when you need it. https://www.lifewire.com/what-is-bandwidth-2625809

Here is a video explained how the package switching work.

https://www.youtube.com/watch?v=B1tElYnFqL8

He talks about that each packet contains IP address and sequencing information, so the packets can travel any path on the internet to their destination, they do not follow each other and they can find the fastest channel available at any instant. Also, they do not need to arrive in sequence. Therefore, the packet switching internet is more flexible and efficient if some amount of delay is acceptable.

“There is no reason anyone would want a computer in their home.”

Ken Olsen, founder of Digital Equipment Corporation, 1977

This prediction appeals to me because I am curious about that why the Ken Olsen as a founder and CEO of Digital Equipment Corporation thinks computers are not popular in the market. Everyone benefits from the invention of computers. Even in 1977, computers can help people deal with many things, such as cumbersome calculations and playing games.

However, I learned that Olsen does not mean that the computer is useless.

“I did make a number of statements and still make statements that people don’t understand about computers or delight in misquoting. A long time ago when the common knowledge was that PCs would run our lives in every detail, I said that if you stole something from the refrigerator at night you didn’t want to enter this into the computer so that it would . . . mess up the computer plans for coming meals.” As Ken Olsen explained many times, what he was repudiating was the idea of a home computer so controlling that residents’ engaging in ordinary human activities would create a source of conflict. https://www.snopes.com/fact-check/ken-olsen/

Therefore, Olsen just does not accept that the computer in the home controlling everything and does not object to the concept of a PC at all. This prediction is a misinterpretation.

what happens when you type an URL in the browser and press enter? The first stage is the browser checks the cache for a DNS record to find the corresponding IP address. Every single URL on the internet has a unique IP address assigned to it. An Internet Protocol address (IP address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication (https://en.wikipedia.org/wiki/IP_address)  For example, a www.temple.edu has an IP address of 155.247.166.60, and the domain name is “temple.edu”. It means you can reach www.temple.edu by typing http://155.247.166.60 on your browser. This is the link you can check the IP address: https://ipinfo.info/html/ip_checker.php when you type a URL, it will show you a corresponding IP address and the domain name.

An IP address is not easy for humans to remember; we cannot remember different sets of numbers for all websites we regularly access. Therefore, it is easier to remember the name of the website using an URL and let DNS do the work for us with mapping it to the correct IP. (https://medium.com/@maneesha.wijesinghe1/what-happens-when-you-type-an-url-in-the-browser-and-press-enter-bb0aa2449c1a)

Here’s a list of devices that will store a cache in the order they’re checked

• browser cache. The browser maintains a repository of DNS records for a fixed duration for websites you have previously visited.
• operating system cache. If it is not found in the browser cache, the browser would make a system call to your underlying computer OS to fetch the record since the OS also maintains a cache of DNS records.
• router cache. If it’s not found on your computer, the browser would communicate with the router that maintains its’ own cache of DNS records.
• ISP cache. If all steps fail, the browser would move on to the ISP. Your ISP maintains its’ own DNS server which includes a cache of DNS records which the browser would check with the last hope of finding your requested URL.

A DNS lookup of one of the root servers doesn’t exactly take a long time, but it is quicker to check a local cache, so one thing we can do to improve performance is to suggest the mapping stays in local caches longer. (https://vanseodesign.com/web-design/browser-requests/)

We send e-mails or texts every day by using phones or computers. But how does this work? The Binary encoding is the critical process to convey information. “Encoding is the process of converting the original information to code for storage or processing.”(PPT wk03-1, p7) If we want to share an image or a video, the computer will convert the information to a series of codes instead of an image or a video directly. The American Standard Code for Information Interchange (ASCII) is “the common standard code to represent numbers, letters of the alphabet, and certain symbols and computer commands in binary form.”(ppt wk03-1, p9)

Here is the table of ASCII codes: 

Decimal system is the number system that uses a notation in which each number is expressed in base 10. We always use the decimal system in real life because it is very convenient.  I think the reason for the rose of decimal system is that we have ten fingers on our hands which could be used for counting. However, if people use them on a computer, it is too much characters to handle. Therefore, we need something simple, that is binary. The binary system used by computers based on two numerals; 0 and 1. They are called bits.Eight binary bits make a byte. The binary system makes encoding process unique, standardize, and robust in a computer, which effectively helps a numbering system to represent accurate informations.

Why Do Computers Use Binary?

“A single switch can be on or off, enabling the storage of 1 bit of information. Switches can be grouped together to store larger numbers. This is the key reason why binary is used in digital systems.” 

(https://turbofuture.com/computers/Why-is-Binary-Used-in-Computers)

Here are four pictures to show the comparison between the decimal system, and the binary system.

(https://en.wikipedia.org/wiki/Power_of_10)

In addition, there are two more numeral systems called the octal system and the hexadecimal system. The octal numeral is the base-8 number system and uses the digits 0 to 7. Hexadecimal is a numeral system with a base of 16. It uses sixteen distinct symbols, most often the symbols 0-9 to represent values zero to nine, and A-F to represent values ten to fifteen.

In short, different numeral systems are mainly because their base is different.  However, various forms of expression can represent the same meaning. Here is the example.

In my opinion, every numeral system can be adopted, but we should take the best choice according to the situation. In the digital world, the binary system is the optimal choice.

Why does a computer use binary system instead of another numeral system? Because there is a physical limitation on how computers work. Everything a computer does comes down macro-transistors. Transistors are made from silicon, a chemical element found in sand, which does not normally conduct electricity . Silicon is a semiconductor, which means it’s really a conductor (something like a metal that lets electricity flow.) Two switches that are On and OFF. With binary, an on switch means 1 and an off switch means a 0. Numbers can be encoded in binary format and stored using switches. The digital technology which uses this system could be a computer, calculator, digital TV decoder box, cell phone, burglar alarm, watch. Values are stored in binary format in memory, which is basically a bunch of electronic on/off switches.(https://turbofuture.com/computers/Why-is-Binary-Used-in-Computers)

Several types of data encoding systems are used by digital technology for representing data which is not specific numbers. The data could be names and addresses in a database, temperature levels measured in a room. Therefore, the binary system is the most efficient to be used in the digital world.

Last week, we learned an important thing in the digital world, that is, communication. There is no doubt that technology makes communication more convenient. From the inconvenient long-distance communication to the current use of mobile phones, you can reach strangers on the other side of the ocean. The way of communication is constantly changing.

Information, signal and message are three parts to communication of information. The lack of one of them cannot be communication of information.In the past, people’s communication mostly relied on letters, they could not hear sounds and voices that contained information. Then Thomas Edison invented the phonograph in 1877, and the machine was the first practical storage device.

One of the impacts of the technology is that education has became more efficient. In the past, the way to get education was by the paper, and teachers had to teach others face to face. The resources were limited, so many people could not get education. However, at present, the learning method has became more and more, that we could learn from internet and books. Also, there are a lot of useful tools that we can take advantage to like PPT.

Here is a video that introduces the history of technology in education.

We can see the technology changed the ways of education and learning methods. We are not able in the past to get data, information, and knowledge so quickly with flexibility.

Hi, everybody.

I am Jiaxi Xie from China and I am a junior at Temple University. My major is Finance. By taking this course I want to learn more changes that I don’t know brought about by technology, and how to use technology to live better. So I will share some impacts of technology with my thoughts. Hope we can learn something worthwhile in Digital world 2020.