What should you do before the presentation?

What should and shouldn’t you do during the presentation?

What should and shouldn’t you do after the presentation?

When working in groups or writing a report, we need to make a presentation. The basic structure of a presentation including introduction, body and conclusion. Befor the presentation, you should known your audience, make an outline what you want to present, practice and internalize, visualize your succes, turn off the phone before presenting, check the equipment in advance. During the presentation, you use gestures and body language to express ideas, make eye contact, look at the audience, do not look at the floor or ceiling, do not just look at the paper and read, use personal stories or experiences as examples. After the presentation, you should thank the audience after they ask you a question, try to answer the audience question, in case you do not known the answer, admit that and promise to provide the answer latter.

Make a short video (1-3 minutes) following the situation below.
Situation: Your friend is going to make his/her first presentation in English. He/ She asks for advice. Make a short talk to show him/ her how to make an effective presentation using the following suggested questions:

What is the basic structure of a presentation?

What should you do before the presentation?

What should and shouldn’t you do during the presentation?

What should and shouldn’t you do after the presentation?

https://drive.google.com/file/d/1McyfXwQqqJb9vdCmM2Z1PKrtxjFLd2Zp/view?usp=sharing

How many kinds of bearings do you know?What are they used for?What are their components?What are their main features?What are their applications?
https://drive.google.com/file/d/1akjujQSbTcabUL-BQMKEUCaHuRFrZl3_/view?usp=sharing

Write a paragraph (120 - 140 words) to compare two types of drives using the suggested questions below
What are two types of drives?
What are the functions of each type?
What are the differences between them (materials, operation, slippage, efficiency, maintenance, etc.)?
What are some applications of each type?

Drives are divided into 2 types including belt drive and chain drive. Belt drive is used to transmit powers from one shaft to another by means of pulleys. Unlike belt drive, chain drive is used for transmitting powers between parallel shafts. Belt drive is made of rubber, flastic. While, chain drive is made of metal. Belt drive can reduce noise and vibration. It also doesn’t need to lubricate. However, chain drive requires frequent lubrication and it can cause noise and vibrations. Belt drive is affected by weather condition but chain drive is not. The disadvantages of belt drive is that it can slip and stretch, it requires more tension. Belt drive have low efficiency but chain drive have high efficiency.

Make a video (1-3 minutes) to talk about different types of gears using the following suggested questions.

-What is a gear?
-What are its functions?
-How many common types of gears are there? What are they?
-What are their features?
-What are their applications?
https://drive.google.com/file/d/1ChxCz59hvJZOHvAqS2tXTGjGCOzGVDHV/view?usp=share_link


Make a video (1-3 minutes) to compare two types of drives using the suggested questions below

-What are two types of drives?
-What are the functions of each type?
-What are the differences between them -(materials, operation, slippage, efficiency, maintenance, etc.)?
-What are some applications of each type?
https://drive.google.com/file/d/12gDYXLZubRYsWSqKHHoRaR442xyScyba/view?usp=share_link

In the first step, the part is cast. In this process hot liquid of metals is poured into a container and then cooled to make the correct shape.

The cast iron is then turned on a lathe to remove excessive materials.

Next, the holes are drilled on th surfaces of the materials with a drill.

After drilling, the material is covered with paint. When the paint is dry, the parts are bolted together using nuts and bolts.

The final step is inspection. The work is checked carefull to make sure that the part has been made properly 

Look at the pictures of the manufacturing process of a car wheel and the suggested questions. Make a video (1-3 minutes) to describe the manufacturing process of the wheel.
-What is the name of the manufacturing process?
-What’s the product made of?
-How many steps are there in the manufacturing process?----What are they?
-How does each step act?
https://drive.google.com/file/d/1gpfdcUbs87o31tBN9TR3_PFsFQ-MWj_u/view?usp=share_link

Make a video (1-3 minutes) to describe the manufacturing process of a gear using the following suggested questions and pictures.
-What is the name of the manufacturing process?
-How many steps are there in this manufacturing process?
-What are they?
-How does each step act?
https://drive.google.com/file/d/13Ja8Biv-2zi-jBM4yNtzgEIw8LQlBc3p/view?usp=share_link

Plastic is divided into 7 types identified by numbers from 1 to 7. The first type is PET, the most widely plastic in the world. This plastic has the properties of oxygen prevention so it used to make food and drink packing like beverage bottles. Next is HDPE which not affected at high temperature of up to 120'C and kwown as the easiliest recyclable plastic polymers in the world applied to product grocery bags, milk jugs, recycling bins,... The third is PVC divided into rigid and flexible. Rigid is largely used in building and construction industy while the Flexible ones is now replacing traditional building materials in various applications. Move to LDPE, the main ingredient of the most infamous plastic bags. This type is flexible, odorless, transparent,... so it can be used to product plastic bag, six-pack rings and containers. The fifth is PP. Being hard and sturdy, withstand high temperatures, PP can be found in car parts, thermal vests or yogurt container. Highly inflamable, inexpensive resin unit weight and easy to create is the properties of sixth type - PS that be used in beverage cups, insulation, packing materials to egg cartons and disposable dinnerware. Lastly, plastics which can be identified in 6 types above is included in group 7. Best known as the application in PC, this type can create sunglasses, sport and safety goggles, also in mobilephone or CD. It type is almost never recycled.
Plastic is a synthetic material that uses polymers as a main ingredient. It is able to mould or shaped easily, can be used to make variety of products. Plastic has properties of durable so it has a long life compared to many other product and retain their shape and stregth. It is lightweight so can be used in manufacturing airplane interiors and exterior parts. Plastic is also unreacted by chemical so it can be used to make food containers. In addition, compare to other packaging materials, plastic is also quite cheap. In the past, we couldn't mould plastic in complex shapes. At the present, it is possible to replace components in engines with plastic. And furthermore, with modern technology, we will be able to make plastic from any kind of nature materials. Besides the advantages of plastics, they also have some disadvantages that people should consider when using them. First, plastic hurts the environment. It leads to all sorts of pollution and especially poor countries will suffer the most. Second, recycling of plastic may not possible. Some plastic items cannot be recycled and will therefore be either have to be burned or disposed into landfills. In conclusion, plastic is a material that has many important advantages. However, the use of plastic also implies serious environment problems.


Make a short video (1-3 minutes) to talk about basic information of plastic (qualities and uses of plastic) using the following suggested questions.

-What is plastic?
-What are the properties of plastic?
-What could/ couldn’t people do with plastic in the past?
-What can/ can’t people do with plastic now?
-What is the future of plastic?
-What are the advantages/ disadvantages of plastic?
https://drive.google.com/file/d/12gDYXLZubRYsWSqKHHoRaR442xyScyba/view?usp=share_link


Make a video (1-3 minutes) to present your understanding of plastic.

As can be seen in figure 1, this is the process of extrusion moulding. There are 6 steps in this process. First, we move the polymer pellets from the hopper to the cylinder. Second, an electric motor turns the screw in the extrusion moulder. Next, the cord polymer pellets move along the cylinder. Beside, heaters warm the polymer pellets to turn them into a liquid. After that, the warm, soft molten polymer moves along the cylinder. Finally, the machine pushes the molten polymer out into the mould.
Write a paragraph (120-140 words) about typical problems typical problems of plastic injection moulding and explain causes and solutions to these problems.
From my point of view, there are 3 typical problems of plastic jnjection moulding. They are short shot, void and sink mark. As I know, short shot is caused of 2 reasons. Firstly, there is not enough plastic in the shot. Secondly, the plastic pressure loss in the mould is too high. There are 3 ways to avoid these causes. The first one is that we should check the shots continuously and use plastic with high melting capability. Next, we had better increase fill speed, plastic and mould temperature. Then, we need to increase gate size and runner. Another problem is void. It is caused of 2 reasons. Firstly, it is caused by plastic shrinkage (a hole suddenly develop in a thick section during cooling). Secondly, plastic volume changes when plastic is heated or cooled. There are 4 ways to avoid these causes. The first one is that we should increase the injection pressure to force more material into the mould and reduce shrinkage. Next, we had better reduce wall thickness. Besides, we need to slow down cooling rate. Then, we ought to increase gate size and locate it at the thick part of the moulding. The last one is sink mark. . It is caused of 2 reasons. Firstly, the internal stress is to high. Secondly, the part has too low a surface rigidity. In conclusion, the plastic shrinkage occurs on the outside of the part. There are 4 ways to avoid these causes. First, I think we should have enough shot size. Next, we had better increase holding pressure and holding time. Then, we need to reduce mould temperature. Finally, we ought to reduce wall thickness for faster cooling.

Make a short video (1-3 minutes) to describe the following plastic moulding process using the diagram below

https://drive.google.com/file/d/1vSBLvkp32YaozqUVf4NSNCX2LIg4zS1L/view?usp=share_link


Make a short video (1-3 minutes) to talk about typical problems typical problems of plastic injection moulding and explain causes and solutions to these problems.

https://drive.google.com/file/d/1QjHbbTusX-3tnz544_bnBAb2iKdJXp3V/view?usp=share_link

A lathe is a metal cutting machine. It has a circular motion around the center of the workpiece that produces cutting speed. The tool feed motion is the reciprocating motion of the tool including: longitudinal and transverse. Lathes are used to process parts with cylindrical, slanted, profiled, threaded, rhombic, and cut-off parts. Several types of maintenance jobs and their schedules for selected machine tools such as Check water line pressure gauges, Check air pressure, Warm up spindle – low speed for five minutes, Clean chip filter, Inspect all filter, Check coolant levels, Inspect oil/ grease, Top up oil levels, Inspect spindle bearing, Inspect drive belt and Change/ inspect oil. Each job usually has a different time, so the importance is also different. Daily maintenance tasks are usually arranged at the beginning and then weekly tasks. the last one is maintenance work every half year. These jobs are less prone to errors. Continuous maintenance will help the machine work better and avoid wasting repair if something goes wrong.



You are a maintenance staff.

Make a video (1-3 minutes) to talk to your customers about maintaining a machine tool he/she bought from your company. Then give recommendations for maintaining the machine tool in short-term and long-term period.

https://drive.google.com/file/d/1eOroP4M-X3UFfUni2QkkE-QuFfbGgur7/view?usp=share_link