Topic 36: Inventions (Phần 2)
19220 lượt thi 40 câu hỏi 60 phút
Text 1:
Most households in the UK will have a broadband connection and a lot of those houses will also have experienced connection or speed issues. But what if there was a way to connect to the internet and benefit from a direct connection with much faster speeds? Enter Li-Fi.
Li-Fi stands for Light Fidelity and is a Visible Light Communications (VLC) system which runs wireless communications that travel at very high speeds. With Li-Fi, your light blub is essentially your router. It uses common household LED light bulbs to enable data transfer, boasting speeds of up to 224 gigabits per second.
Li-Fi and Wi-Fi are quite similar as both transmit data electromagnetically. However, Wi-Fi uses radio waves, while Li-Fi runs on visible light waves. This means that it accommodates a photo-detector to receive light signals and a signal processing element to convert the data into “streamable” content. For example, data is fed into an LED light bulb, it then sends data at rapid speeds to the photo-detector. The tiny changes in the rapid dimming of LED bulbs is then converted by the “receiver” into electrical signal. The signal is then converted back into a binary data stream that we would recognise as web, video and audio applications that run on internet-enabled devices.
While some may think that Li-Fi with its 224 gigabits per second leaves Wi-Fi in the dust, Li-Fi’s exclusive use of visible light could halt a mass uptake. Li-Fi signals cannot pass through walls, so in order to enjoy full connectivity, capable LED bulbs will need to be placed throughout the home. Not to mention, Li-Fi requires the light bulb is on at all times to provide connectivity, meaning that the lights will need to be on during the day. Additionally, where there is a lack of light bulbs, there is a lack of Li-Fi internet so Li-Fi does take a hit when it comes to public Wi-Fi networks.
However, using Li-Fi instead of Wi-Fi, you’ll negate lots of security problems associated with shared and often overloaded broadband networks. It will also be advantageous in areas where radio frequency waves do not reach. Due to its impressive speeds, Li-Fi could make a huge impact on the internet of things too, with data transferred at much higher levels with even more devices able to connect to one another.
(Source: https://www.techworld.com/)
Text 2:
The field of 3-D printing comes with a new set of legal questions hospitals using the technology will need to consider, said Bruce Kline, a technology licensing manager who oversees patents for new technology developed at Mayo Clinic. For starters, he said the STL file printers use are a lot like MP3 music files, in that they can be protected under copyright and require licensing to use. Copyright violations can occur if a purchased STL anatomical model file for rare disease is illegally shared with another institution that did not purchase the file from the vendor that created the file.
Under the law, if a device has a functional use it falls under patent law. If it is not functional, it falls under copyright law. Kline said most medical 3-D printing for educational models and complex anatomy evaluation currently falls under copyright. But, he said that will rapidly change in the coming years as customizable 3-D printable medical devices see wider use.
Additive manufacturing (AM) allows the creation of patient-specific devices at the point of care. Kline said an interesting fact is that these devices are FDA 510(k)-exempt if produced by a hospital instead of a medical device vendor. He said this blurs the lines between traditional vendor relationships, since the hospital can now become the manufacturer. However, if a hospital makes a device, it also becomes liable for it. He advised that it might be better for a commercial vendor to make the device for the hospital so the vendor assumes the liability of the device. Custom-made medical devices are also exempt under FDA regulations, Kline said. So, if a physician creates or modifies a device to meet the clinical needs of a specific patient’s anatomy, he said it is acceptable to use under current FDA rules. This may leave the door wide open for use of 3-D printed devices that are customized for each patient using their own 3-D imaging datasets.
It is possible printable device files may become available in the next few years to customize and print on demand. However, Kline said it will be much more difficult to enforce patents on these types of devices. He explained if someone makes one or two devices, there is no economical way for the creator of those device files to go after the user/maker of unlicensed copies of the device to claim lost profits.
(Source: https://www.dicardiology.com/)
Text 3:
Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time(less that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that “this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”
The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920’s. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.
(Adapted from https://studylib.net)
Text 4:
Facebook users spend an average of more than 15 hours a month on the social networking site. While there are plenty who caution against such intensive use — and there are a number of studies detailing the harm Facebook could potentially cause — there also are lots of reports extolling the site’s virtues. As the social media giant prepares for its upcoming initial public offering, here are some ways Facebook just might be good for you.
Spending time on Facebook can help people relax, slow down their heart rate and decrease stress levels, according to researchers from the Massachusetts Institute of Technology and the University of Milan. In a study published earlier this year, researchers studied 30 students and found that a natural high was sparked when they were on the social media network that led to the relaxed heart rates and lower levels of stress and tension. In the study, the students were monitored in three situations: looking at panoramic landscapes, performing complicated mathematical equations and using Facebook. While the first situation was the most relaxing to students and the math problems were the most stressful, the time on Facebook uncovered high levels of attractiveness and arousal. The findings support the researchers’ hypothesis that Facebook’s success, as well as that of other social media networks, correlates to the specific positive mental and physical state users experience.
While many may argue that social media networks only distract employees, research shows the opposite may be true. Research from Keas.com found that a 10-minute Facebook break makes employees happier, healthier and more productive. The study examined workers in three groups: one that was allowed no breaks, one that was allowed to do anything but use the Internet and one that was allowed 10 minutes to use the Internet and Facebook. The Facebook group was found to be 16 percent more productive than the group that was not allowed to use the Internet and nearly 40 percent more productive than the group that was allowed no breaks. “Short and unobtrusive breaks, such as a quick surf on the Internet, enables the mind to rest itself, leading to a higher net total concentration for a day’s work, and as a result, increased productivity,” said Brent Coker of the department of management and marketing at the University of Melbourne in Australia.
Facebook is also in the business of matchmaking. Research shows that nearly 60 percent of singles will friend someone new on Facebook after meeting them in person. If they like what they see, 25 percent are likely to contact their new love interest via Facebook. Once the courting is over, nearly 40 percent of those social networking adults will update their relationship status on Facebook, with just 24 percent telling their friends first. Facebook use between couples will continue through the dating process, the research shows. Throughout the day, 79 percent of couples said they send partners Facebook messages or chat on the social network. In addition, more than 60 percent would post romantic messages on their significant other’s Facebook wall. When the relationship ends, more than half of those surveyed immediately update their status to single, which automatically sends out a notification to their friend list to start the dating cycle over again.
(Source: https://www.businessnewsdaily.com/)
Text 5:
In 1959 Xerox created the first plain paper copy machine. It was one of the most successful products ever. The company name Xerox grew into a verb that means “to copy,” as in “Bob, can you Xerox this for me?” Around 50 years later, the same thing happened to Google. Their company name grew into a verb that means “to do an internet search.” Now everyone and their grandma knows what it means to Google it.
Unlike Xerox, Google wasn’t the first company to invent their product, not by a long shot. Lycos released their search engine in 1993. Yahoo! came out in 1994. AltaVista began serving results in 1995. Google did not come out until years later, in 1998. Though a few years difference may not seem like much, this is a major head start in the fast moving world of tech. So how did Google do it? How did they overtake their competitors who had such huge leads in time and money? Maybe one good idea made all the difference.
There are millions and millions of sites on the internet. How does a search engine know which ones are relevant to your search? This is a question that great minds have been working on for decades. To understand how Google changed the game, you need to know how search engines worked in 1998. Back then most websites looked at the words in your query. They counted how many times those words appeared on each page. Then they might return pages where the words in your query appeared the most. This system did not work well and people often had to click through pages and pages of results to find what they wanted.
Google was the first search engine that began considering links. Links are those blue underlined words that take you to other pages when you click on them. Larry Page, cofounder of Google, believed that meaningful data could be drawn from how those links connect. Page figured that websites with many links pointing at them were more important than those that had few. He was right. Google’s search results were much better than their rivals. They would soon become the world’s most used search engine.
It wasn’t just the great search results that led to Google becoming so well-liked. It also had to do with the way that they presented their product. Most of the other search engines were cluttered. Their home pages were filled with everything from news stories to stock quotes. But Google’s homepage was, and still is, clean. There’s nothing on it but the logo, the search box, and a few links. It almost appears empty. In fact, when they were first testing it, users would wait at the home page and not do anything. When asked why, they said that they were, “waiting for the rest of the page to load.” People couldn’t imagine such a clean and open page as being complete. But the fresh design grew on people once they got used to it.
(https://www.ereadingworksheets.com/)
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