Synthesis Post

Engineering is a vital aspect in life to keep a balance between what the problems are now and what we need to do about them. With the importance of engineering comes creating objects never thought of before while also it entails issues in ethics, and stereotypes.  

Ethics is a huge part about being an engineer. The products being designed are used in the public's daily lives, and many times, the product is keeping the user alive. For example, every time you are in a car, on a bridge or using any type of technology, you expect it to be built in a way where safety was the highest concern before cost. Unlike many fields including business, or law, safety is put before money. If you would like to read more about ethics in engineering refer to this post. Prompt Two: Defining Ethics

The stereotype that being an engineer is a man’s job is not only false, but sadly it is heavily influencing the amount of women currently holding engineering positions. This all goes back to what kids study in school. Many places are seeing declines in women participating in advanced level math and science courses, which is leading to them to not furthering their education into a science, technology, engineering, and mathematics, or a “STEM” field. An example where this is shown can be found in this Women and Minorities in Engineering

Since Engineering is a STEM major, high school students interested in engineering should take many STEM related classes during their time in high school.  These classes include advanced courses in mathematics, chemistry and physics.  These classes will make students more prepared for the coursework they will experience during their time at college.

In some countries, the number of high school students that are taking STEM classes is decreasing. This can lead to a shortage of STEM degrees in the future. Students, both boys and girls, should be taught about the importance of STEM majors at a very young age, and should be encouraged by their parents to take STEM classes in high school. Even though not everyone enjoys this field, it is important that students get the opportunity to experience engineering. Australia struggling to produce engineers

The world of engineering is forever going to keep changing and improving. As well as using that improved technology to make further changes to put us into the lead in the race for new technology.  In order for changes to be made in engineering, we have to look back at the history, making sure the mistakes that were made then, are not repeated here in the present and future which would ultimately set us backwards.

One of the main goals of engineering is to improve designs and create new materials so they are the best they can be, while also keeping costs low and efficiency high. The advantages of these kinds of improvements would be that a new product would have the same strength as other materials such as steel, for example, but with much less weight and production costs. Some products could eventually be made with less quantity of material while having the same performance. Finally, more ways could be found to produce the same product at a smaller cost, simpler manufacturing steps, and with less impact on the environment. A Steel Makeover

Some would say the future is now and the future of technology is a thing of the past.  Present day engineers have already worked ahead on futuristic technology, one example being artificial intelligence. Artificial intelligence is already being used to design products and complete tasks that humans can’t yet comprehend. The main goal for any engineer, when working with artificial intelligence is pretty much trying to create a mechanical brain that can use the data it receives to make decisions without any guidance from others.   Sooner or later, improvements in engineering will allow us to create an A.I. that can function as a separate human being and understand decisions on a human scale. Artificial Intelligence in Civil Engineering

The world issues in ethics, and stereotypes can be seen in engineering, especially with a lack of women filling jobs, but the field as a whole is battling this. Engineering is an exciting field full of futuristic productions while also being a part of history.  Engineering is a vital aspect in life to keep a balance between what the problems are now and what we need to do about them.

Tiny engineering - Headphones

Weiyu Li


When we are walking in the streets, we can see some cool boys or girls wearing the headphones, some of them are in-ear earphones, some of them are headsets. In fact, the earphones are not so simple, the companies try to make the good effect of listening, as a result, the engineering in the earphones are important.

 

Headphones could reduce the noise from outside the environment which constructed from the ear and the headphones. To cancel the lower-frequency portions of the noise, noise-cancelling headphones use active noise control. They incorporate a microphone that measures ambient sound, generate a waveform that is the exact negative of the ambient sound, and mix it with any audio signal the listener desires. Also, the headsets could cancel the noise because of the totally ear-covering. 

Hi-Fi isn't the name of the certain headphones but the quality of the songs. Some headphones might have good quality, they may got low by the reason of the quality of songs. Hi-fi reproduction is a term used by home stereo listeners, audiophiles and home audio enthusiasts to refer to high-quality reproduction of sound to distinguish it from the lower quality sound produced by inexpensive audio equipment, or the inferior quality of sound reproduction that can be heard in recordings made until the late 1940s.Ideally, high-fidelity equipment has inaudible noise and distortion, and a flat (neutral, uncolored) frequency response within the intended frequency range.

resourse of noise reducing headphones

resourse of Hi-Fi

Engineering Olympics

Post By David DeMeo

         An article posted by Janye Bugda is showing the "engineering olympics" that were put on by Wilkes University at a local Pennsylvania high school. These types of events seem to be occurring more and more attempting to spark the interest of high school students to the engineering field.
   
     This specific competition had high school students from Pennsylvania come to display their skills and the winner would receive $10,000 towards their education at Wilkes. The students did not know what the task were going into the competition, but were then asked to complete certain task like creating a water distribution system and a catapult. This challenges the thinking of the students without using research. The students at the event discussed the difficulty in the task and the amount of math and science thinking needed to be successful.
   
   I have personally seen these in my past high school career and was a part of a similar long-term STEM program. These programs allow students to change their high school education and push it towards the STEM fields. The real world is in high demand of engineers as discussed in past blog post.

Source

Exploring Communication: Prompt Three

By Joao Martins

For this prompt, I interviewed Luis Martins, a mechanical engineer that works for Owens Corning, a company that manufactures fiberglass. Luis works as the vice president of global operations. The first thing I asked him about was the writing that he needs to do for his job.  He explained that he usually has to create many excel spreadsheets with data about the performance of the company. He also has to create power point presentations using this data. He later shows the power points to his team where they decide what to do in the future based on the company's results or any unpredicted events. I later asked him about common misconceptions of the engineering fields. He described to me that a lot of people assume engineers are introverts and keep to themselves, but this is wrong. According to him, communication is essential for any engineering field, and being able to work well in a team is extremely important.    

How To Get That Engineering Internship.

By: Alex Vu

Internships in the college life are the golden snitch of Harry Potter, they go by fast and they are very hard to secure.  But in order to get an engineering internship, you have to take any opportunity the first chance you get or they will disappear in an instant.  The best start is to join every club you can, participate in every activity you can and the opportunities will start falling in.

Here are a few basic steps to improve your resume so you can get the internship.

1)Make a goal that peaks your interest and work towards it.

• Writing 
• Exploring

2) Pick up a new hobby.

• Learn an instrument 
• Play a sport

3) Read anything that has words on it. Because you could possibly learn something you might not learn in class.

• Books
• Magazines
• Blogs

4) Learn different skills.

• New languages
• Driving
• "Handy Man"

5) Finally you should travel the world to experience the world's culture and possibly learn how they do engineering and then you could apply it to the engineering we have here.

Source: here

Prompt#8 The serious difference between the theory and the fact

Weiyu Li

As an international student, I finished my high school in China. During my time in high school, I attend the China Adolescents Science & Technology Innovation Contest. With the experience of making the unpowered planes, I started to know that there are big differences between the theory and the fact.

Firstly,we designed the blueprint of our unpowered plane. We always tried the plane with long and wide wings like we calculated before. However, the long and the wide wings made the wings heavy, the parts which connect the wings and the body of the plane support too large force, which makes the plane not so firm.

Secondly, the fact includes the fund. For example, the plane we made needs the material named carbon fiber. We found a factory which makes the products of carbon fiber professionally. In fact, the price of that really out of our expect. It's about 6000 CYN per square meter which about 900 dollars.

Lastly, the experiments usually happens out of plans. The planes land out of the range, the weather affects the time of raising our of the atmosphere and the data collecting work is hard during the plane flying. The GPS lost connection with the control base which was supposed to work well. The theory always shows us the maximum of the nice working of all kinds of things. We should think about that well when we are using that.

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What It Takes To Become A Mechanical Engineer

By: Alex Vu


This week I decided to look more in depth into my major of mechanical engineering, exploring the financial aspects and as well as where are needed most.  On average the median annual salary for mechanical engineering in the United States was $83,000 in 2014.  From the year 2012-2022 they only expect the wages as well as number of jobs to only increase by 5 percent.  The biggest increase in jobs by percentage is located on the west coast of the United States averages out to around 19 percent per state.

I also wanted to look at what the road to a mechanical engineering degree looks like and what kind of degrees I would have to achieve. 

Step 1: Get a bachelor degree in mechanical engineering ( 5-6 years)

Step 2: Earn an Engineering License

Step 3( optional): Become certified in engineering

Although it is only three basic steps into becoming an engineer, there are also hundreds of different paths you can take to getting there.

~ source: Learn How to Become

Australia struggling to produce engineers

Post by David DeMeo

           An article posted by an Australian news paper discussed the falling numbers of students who are in science and math courses. This is looking to decrease the already low numbers of engineers produced in Australia. The statistics of high school students taking advanced math classes is falling. "The number of boys studying advanced math at senior high school dropped from 15.9% in 2001 to 11.5% in 2015 while girls studying intermediate math dropped from 30.9% to 20.6%." Prior to this fall, the gender gap in engineering was the main problem and while this is still a large issue, the number of total students in engineering will have to be the focus for Australia. One way they have been dealing with this issue is by bringing in engineers from overseas, but this is not a permanent fix, and without sufficient numbers of engineers in Australia the country will not be advancing as quickly as they plan to. The need for the country to have greater numbers of students in engineering is very important.
     
           As an engineering student, I know that it is not an easy career to take on and if the students interest in math is not there then engineering is definitely not the choice. A possible fix from my point of view is not to attack the idea of engineering and force that on the students, but get the interest in math and science up. Letting the students participate in more fun and interesting projects will show them it is more than just useless numbers on a test.
       
          Using this article, as a current engineering student, I might begin to look for jobs and internships in Australia knowing that there is a demand.

Source

Reusable Rocket Success

By Joao Martins

Space X has been getting a lot of media attention this week for successfully reusing the Falcon 9 first stage rocket. This was one of the first successful attempts in launching a a satellite into orbit and capturing the rocket back for future use. Usually when a satellite is launched, only a few, if any, parts of the rocket are saved for future use. This new type of reusable rocket is very important because it saves a great amount of money and materials when space missions are being planed. This new technology is far from perfect, however. According to Gwynne Shotwell, the president and COO of SpaceX, it took them over four months to fully reassemble the reusable rocket after its previous launch. Their ultimate goal is to be able to reuse the rockets on the same day. The company is currently working on a final version of the Falcon 9, which is supposed to fly its first mission later this year. Shotwell says this latest version is being designed to re-launch multiple times. “The final vehicle design spin that we are doing on Falcon 9, that we will be flying later this year, that should be capable of up to 10 or even more (launches),” she said.

Source:
http://www.theverge.com/2017/3/30/15117096/spacex-launch-reusable-rocket-success-falcon-9-landing 

Observing community Prompt #5

Post by David DeMeo

        This week observed and participated in the Greenpeace club at Michigan State. This club appears to be a club based on the environment from the outside and that is what it is. Every Wednesday there are meetings where topics such as fossil fuels are discussed and plans of action are created. This may seem irrelevant to the topic of engineering but it is very much a key to the field at this time. From windmills being created to be as efficient as possible to tesla creating affordable electric cars engineering is a huge part of the energy field in our current world.
          The Greenpeace club mainly shows themselves to the public through Facebook. A lot of what the public sees is events that the group supports or host and this is what it is actually like within the group as well.
          My experience in the club was very good. I went to a meeting on Wednesday and was able to help brainstorm fundraising ideas and sign up for events I can volunteer at to do my part in the community. The club's representation to the pubic is very similar to what I experienced. The group of people were very nice activist toward protecting the environment. I highly recommend people join this club if you care about our issues with the environment.

The tiny environment created by Engineering

Weiyu Li

This environment mentioned in the topic doesn't mean the space which has different kinds of planets, animals or something else, the environment is the space in the sneakers.

As we all know, there are plenty kinds of shoes, soccer shoes, basketball shoes, training shoes and else. The most creative one and the most fashion one will be the basketball shoes.

In-game sneakers have evolved considerably over the years. From the earlier years where Converse Chuck Taylor and Nike Blazers were the norm and laid the blueprint for sneakers to now where Air Jordans and others offer more variety.

With the use of modern technology designers are able to create footwear the adheres to individual players based on foot structure, on-court movement, and impact of movement. This personalization adds more control, strength, and power to already freakishly gifted athletes.

Basketball researchers use data collected to compile an understanding of a player’s on-court movement in order to create sneakers that are lighter, stronger, and safer. Designers, in partnership with researchers, use high-tech fabric that is both lightweight and durable when designing sneakers that give the players effective footwear.

As a result of this design we have the 9.8 ounce Adidas AdiZero Crazy Light, which is the lightest basketball shoe on the market. Many shoe designers are steering away from using leather as it is heavier and does not serve a useful purpose.

Adidas produces lightweight and comfortable sneakers by mimicking an automobile manufacturing processes to heat-stem individual pea-size thermoplastic polyurethane foam capsules together to offer more cushioning and energy return versus traditional EVA foam.

resources

Artificial Photosynthesis

By Joao Martins

An article recently posted on The Engineer website describes recent developments made in artificial

photosynthesis. Artificial photosynthesis works just like the photosynthesis that plants use to get their energy, except that instead of being performed by plants, it is performed by man-made chemicals. This technology uses sunlight to convert solar energy into hydrogen and oxygen. The discovery of these materials was made by Rice University Chemistry professor Kenton Whitmire. This new technology can be used as clean and renewable way of generating hydrogen, which is what scientists want to use to power cars in the future due to their clean operation. They way the artificial photosynthesis material is made is by combining iron, manganese and phosphorus into a molecule that changes to a gas when a vacuum is applied. Scientists then take these molecules and make them into a film that is then applied to titanium dioxide rods.

Source:
https://www.theengineer.co.uk/new-catalyst-promotes-artificial-photosynthesis/

Rechargeable batteries

By: Alex Vu

Personally I have never really preferred rechargeable batteries, because I always found myself constantly recharging the batteries and never really getting the maximum performance we were promised.  A few advantages I found with rechargeable batteries is a main reason they were made for, which is not having to constantly buy more and more batteries to power my controllers, remotes and other household items. A major disadvantage I found with them is that even though they are not disposable anymore, the charge on them is considerably low.  One major factor I thought of is that this problem could because the battery charge is constantly fading even when it is not in use.

I came across an article that is working on a way to improve the technology to minimize the capacity loss in lithium-sulfur batteries.  Professor Bingqing Wei states that a phenomenon called the polysulfide shuttle effect is responsible for the rapid capacity fade. As the polysulfide begins to disappear in the batteries, it allows other materials to be loss thus losing the capacity in the battery.  Currently they are trying to include ferroelectric nano particles hoping that it would prevent the loss the of the polysulfide particles and the batteries would be able to hold a charge.

Source: Batteries

Women and Minorities in Engineering

Blog By: David DeMeo

          This article discussing an issue that is often brought up with the field of engineering is showing the beginning to a more equal future in the career. Several high school girls were interviewed and discussed their participation in a engineering conference. They discussed the lack of women in the engineering field and their enjoyment in this conference.  It was stated that women only occupy 15% of the engineering career field. This number is extremely low and the conference being held is pushing to get a greater involvement of women and minorities in the field.

          The one day conferences being held are getting minorities and women more excited for the field. I believe that women and minorities are not supplying a large portion of engineers because it is not a social norm for them to be in the field so they are not pursuing it. This is the problem we have and these conferences are fixing that. This article is showing how the conferences are bringing to light the exciting field that it is to women and minorities. Once they see this and their interest begins to grow we will see differences in numbers in the field.
       
           Because of conferences like this one, it will soon become normal to see equal amounts of women and men in the STEM fields.

Source: Engineering

The century product- Super computer

Weiyu Li

The super computers are the computers could work out the large amount of data at the same time that the common computers or people couldn't work out. It is a computer with a high level of computing performance compared to a general-purposed computer. Performance of a supercomputer is measured in floating-point operations per second (FLOPS) instead of million instructions per second (MIPS). As of 2015, there are supercomputers which can perform up to quadrillions of FLOPS.

The supercomputers were introduced in the 1960s, made initially, and for decades primarily, by Seymour Cray at Control Data Corporation (CDC), Cray Research and subsequent companies bearing his name or monogram. While the supercomputers of the 1970s used only a few processors, in the 1990s, machines with thousands of processors began to appear and, by the end of the 20th century, massively parallel supercomputers with tens of thousands of off-the-shelf processors were the norm.

As of June 2016, the fastest supercomputer in the world is the Sunway TaihuLight, in mainland China, with a LINPACK benchmark score of 93 PFLOPS (P=peta), exceeding the previous record holder, Tianhe-2, by around 59 PFLOPS. It tops the rankings in the TOP500 supercomputer list. Sunway TaihuLight's emergence is also notable for its use of indigenous chips, and is the first Chinese computer to enter the TOP500 list without using hardware from the United States. As of June 2016, China, for the first time, had more computers (167) on the TOP500 list than the United States (165). However, U.S. built computers held ten of the top 20 positions.

Resource

Picture From

Nikola Tesla

By Joao Martins

Born in July 1856 in what is now Croatia, Nikola Tesla developed his interest in electronics at a very young age after constantly watching his mother build small household appliances. After getting his electrical engineering degree at the Polytechnic institute in Graz, Austria, Tesla moved to Budapest and starting working at the Central Telephone Exchange. Tesla began having ideas for many new inventions, but after failing to acquire the necessary funding do develop them, Tesla decided to leave Europe and move to America. Upon reaching The United States in 1885, Tesla was hired by famous inventor Thomas Edison. They worked alongside each other for a few months but Tesla ultimately quit after having conflicting interests. Tesla, however, now had enough money to start his own company, which he called the Tesla Electric Company. Tesla now had the necessary funding he needed and in 1887, he successfully filed many patents for his Alternating Current based inventions.
Tesla new Alternating Current (AC) system was seen as a better alternative for providing long distance power, as opposed to Edison's Direct Current (DC). People began investing in Tesla's AC systems so Edison created a negative-press campaign in attempt to stop Tesla. This, however, did not work and Tesla and his team were chosen to design the first AC Hydroelectric Power Plant at the Niagara Falls. The power plant was a huge success and AC technology quickly became the better choice for providing electrical power, which is still used world wide to this day.

Source:
http://www.biography.com/people/nikola-tesla-9504443

Prompt #4 Considering Delivery and Style

By: Alex Vu

Depending on what kind of article you come across, it can either peak your interest or completely bore you to death and that all depends on the delivery, style and targeted audience.

The first example, is a magazine article about 3D image correlation but the main is how they present their delivery. The targeted audience for something like this is usually professors or people looking for random knowledge.  The author of this magazine article uses so much detail explaining every single process of the procedure. It is almost as if you are conducting the process yourself. The style of the article is more of a direct approach to tell you exactly how and why is happening the way it is.

The second example is a scholarly article focused on more about how people are changing technology and how people are getting involved in engineering projects around the world.  The delivery on this is to emphasize how important these projects are to our community around the world.  The style of the article is trying to influence people to get out and become a part of this technology revolution.  The targeted audience is mainly towards people that want to get out and make a change to the world.

The purpose of the magazine is to show you how a process is done and the purpose of the scholarly article is to hopefully influence you to try and make a difference in the world.  Its really difficult to say which one we trust, because each have their own purpose in what each want to accomplish.

Scholarly article:
http://www.jstor.org.proxy2.cl.msu.edu/stable/pdf/24164202.pdf
Magazine article:
link

The miracle in Engineering-Empire State Building

Weiyu Li
The Empire State Building is one of the Seven Miracles Of Engineering in the World judged by ASCE(The American Society of Civil Engineers). It is one of the most tallest buildings in the world.

The Empire State Building was supposed to be built about 1050 feet to be the tallest building at that time. At that time, it was Great Depression. The rich showed off their wealthiness by competing the height of the buildings they built. John Jakob Raskob, the owner of the Empire State Building was not happy about the height, he wanted it to be higher. The designer then added an 200-feet tower at the top of the building, made it reach the height of 1250 feet.
The miracle of the Empire State Building isn't only about the height, also about the seed of it. In 1945, the B-25 plane hit the Empire State Building at speed of 320 kilometers per hour. However, the Empire State Building didn't be destroyed, it only took 2 days to reopen the building to the public.

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Artificial Intelligence in Civil Engineering

By: Alex Vu

The idea of artificial intelligence is to be able to make a program that can perform a single human function without accounting for the human error.

In any field that is run by people can not escape the fact of human error, even if you have the brightest people in the world working on a project there will still be human error.  In Civil engineering the engineering design, construction management, and the decision making were mainly influenced by many uncertainties that included math, physics and mechanics.

link here

Essentially we would be engineering a mechanical human that can be programmed to solve complex problems without any uncertainty and we would have a "perfect world".

Even with super intelligence, it is made by people so it will have human error no matter how hard we try. If used in the wrong way, it can be used for dangerous weapons or it can sometimes veer off the path of the function we programmed it to perform.

Sources:

~ Artificial Intelligence in Civil Engineering

~ Benefits and Risks of Artificial Intelligence

Prompt 10: Recognizing Truth

By Joao Martins

The QS Top Universities website, which ranks Universities throughout the world, posted a video that is titled "5 Signs You're an Engineering Student". The signs that are described in the video include knowing everything there is to know about bridges, thinking Legos are the best toys ever, always trying to fix things that are broken, and having been to two lectures before your friends are even awake.
Many of the things described are not representative assumptions of engineering in general. For example, only a few fields of engineering require complete knowledge of bridges, and thinking legos are the best toys ever is a personal opinion which can be shared by students of other majors too. Always trying to fix everything is also not representative because there are some engineering students that just want their degree because of the potential for making a great amount of money int the future. These students are not interested in fixing things because they are not passionate about the field in general, while at the same time, people can enjoy fixing things but pursue a different, unrelated major. The part about having lectures before your friends are even awake is also false. As an engineering student myself, I know for a fact that many of my friends that are not engineers wake up much earlier than I do.
This video being titled "5 Signs You're an Engineering Student" is a misinterpretation of the engineering field because after watching, the viewer (who can be inexperienced with the engineering fields) expects this to be true for every engineer student, when in many cases it is not.

Source:
https://www.topuniversities.com/student-info/videos/5-signs-youre-engineering-student

Reverse Engineering

Post by: David DeMeo

          In an article posted by Space.com a project by a aerospace company, NovaWorks who are using a unique strategy to build satellites. The usually process includes shrinking technology down as much as possible and getting all of the equipment to fit in the body of a satellite. For a small company like tis with less funding to get smaller technology they came up with a new plan. They decided to start engineering the body of the satellite around their equipment. This type of thinking is exactly what is taught to engineering students. In my classes I see this where the teachers assign us with problems and we need to find a unique way to solve it. The key to engineering is problem solving.
         
         What I took from this article is that there is always another way to do a task. There is never only one way to engineering something and this is also connecting back to my classes. In my engineering class a task was assigned to build a robot with a claw that could pick up a ball, and no two robots were the same, even similar. This small company came up with a great idea, that will save money, and has never been done before. Their satellites have been taking trips to space already, one going to the international space station and another planning on taking a trip with a SpaceX rocket. Their design ideas will most likely be seen implemented in  other projects. Engineering is about thinking outside the box and completing task in the most efficient way possible and that is what NovaWorks accomplished. Ill be sure to use this type of thinking when handling my own projects.

Source: http://www.space.com/35885-novawurks-building-satellites-around-instruments.html

The future weapon-laser weapon

by Weiyu Li

I believe almost everyone can imagine what laser weapon would like because of the future war films such as Star-Wars or Independence Day. The amazing outlook and the giant power must be the main goal of the weapon company today.

The laser weapon is using the laser which contains the high energy to hit the target in long distance or intercept the missiles from the enemies. The laser weapons mainly cost the electricity so the cheap cost is the reason why it is mainly focused of researching. However, this weapon has the critical defect as well. The laser weapon will easily be influenced by the condition of the weather such as fog, rain, snow. After that, the condition of the atmosphere can affect the laser weapon as well. The thermal blooming or atmospheric disturbance and other things can also decrease the power of the laser or even let it disappear.
 Several things make the laser weapon has such an enormous power. First of all, the high temperature of the point focused by the laser weapon could easily melt the shell of most things. Also, the force of the laser beam could make the target shape change. Last, the x-ray and the ultraviolet ray could damage the inner parts of the electric products which is the most deadly point to modern military weapons.

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Mercury-Arc Rectifiers

By: Joao Martins

Have you ever wondered how high voltage AC (Alternating Current) was converted into DC (Direct Current) before the 1970's? Well, probably not, but this is how it was done: using Mercury-Arc Rectifiers.
In the 20th Century, scientists and engineers needed a new and more efficient way of converting Alternating Current, which changes from negative to positive current very quickly, to Direct Current, in which the current always flows in the same direction. The old technology that performed this task was incredibly inefficient and it was also prone to failure, so in 1902, Peter Cooper Hewitt invented the Mercury-Arc Rectifier. This is how it works: A pool of liquid Mercury sits at the bottom of a closed glass bulb. The Mercury acts as a Cathode, while at the top of the bulb carbon rods act as the Anode. When electricity and heat is applied, the Mercury pool emits electrons which are attracted to the carbon anode. This "electron arc" makes the current only flow in one direction only, effectively converting AC into DC. This process is a lot more efficient than older methods, and quickly Mercury-Arc Rectifiers began to be used to power trains, streetcars, and industrial motors. These rectifiers do have some downsides, however. The mercury in it makes it really dangerous for the people that work around it if one breaks, and they take up a lot of space. After 1970, most of them were replaced after the invention of semiconductors, which are more efficient and not toxic, but some Mercury-Arc Rectifiers are still in use to this day powering older parts of the NYC subway system among other things.

Source:

Cory, B.J.; Adamson, C.; Ainsworth, J.D.; Freris, L.L.; Funke, B.; Harris, L.A.; Sykes, J.H.M. (1965). "Chapter 2". High voltage direct current converters and systems. Macdonald & Co. Ltd