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The basic structure of a presentation includes an introduction, main content, and a conclusion. The introduction should grab the audience's attention, state the purpose of the presentation, and provide an overview of the main points. The main content should be organized and presented in a logical order, with supporting visuals to enhance understanding. The conclusion should summarize the key points, restate the purpose of the presentation, and leave a lasting impression.

Before the presentation, you should prepare and rehearse your content, ensuring that you are confident and comfortable with the material. You should also check the equipment and setup before starting the presentation.

During the presentation, you should maintain eye contact with the audience, speak clearly and at an appropriate pace, and use body language to emphasize key points. You should avoid reading from slides or notes and using filler words such as "um" and "ah."

After the presentation, you should thank the audience for their time and address any questions or concerns they may have. You should also evaluate your performance and seek feedback to improve your future presentations.

By following these guidelines, you can make an effective presentation that will leave a lasting impression on your audience.

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nice try!
please repeat this word: paper
/ˈpeɪ.pər/ https://dictionary.cambridge.org/dictionary/english/paper?q=paper+

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1. thin, flat material made from crushed wood or cloth, used for writing…

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https://drive.google.com/file/d/14jbY18VunrV_tMfCUHskP3cnRN7X3A1J/view?usp=drive_link

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https://drive.google.com/file/d/14p2kOb8bHek1AIS_1ufwpW5jGGMvvt77/view?usp=drive_link

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https://drive.google.com/file/d/14HyWoeXc1cmy8AslCHIOMZrdOKc9Vhqm/view?usp=drive_link

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https://drive.google.com/file/d/13VQL3YoXXvgl6ZOpppm8PClaZpGEdJWS/view?usp=drive_link

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https://drive.google.com/file/d/12HZOdMDfACGUKGyribkpcz39fJF5RrYb/view?usp=drive_link

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https://drive.google.com/file/d/14Y5-9PTlud3YTFHLN6qvRqEblJUQhvgG/view?usp=drive_link

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https://drive.google.com/file/d/14axJnoO5fvU0FjEhszKnAYXNJ9bAs_kl/view?usp=drive_link

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Lathes are widely used in the mechanical industry, with the function of removing redundant parts to create a complete part. Maintenance of the lathe is also very important. The first is to check the water pressure gauge which needs to be done daily. Next is the air pressure check which also needs to be done daily. Similarly, clean chip filtering also needs to be done daily. Weekly maintenance includes: check all filters, check coolant level and check oil and grease. Finally, the annual maintenance includes: main bearing inspection, transmission belt inspection and oil change. Carrying out maintenance according to the correct procedure and sequence will help to increase the life of the lathe as well as the working productivity of the machine.

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The picture shows the plastic melting process. This process consists of many steps such as melting, cooling, ... first when the plastic is put into the mold under the influence of the heat extruder, it will change from plastic to molten plastic. At this time, toxic gas will be released from the air tube and can be deadly. The molten plastic passes through the nozzle flowing into the molds for reshaping. The plastic is then cooled and taken out of the mold to complete the process. Now the plastic has been shaped into the shape we want to machine.

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Some errors in plastic manufacturing are short shot, void, sink mard, flash,… Causes of plastic short shot: the first, there is not enoughplastic in the shot. And the second, the plastic pressure loss in the mouldis too high. The solution of the problem includes: the first, check the shots continounsly and use plastic with high melting capability. And the second, increase gate size and runner. Causes of plastic void: the first, it is caused by plastic shrinkage hole suddenly develop in a thick section during cooling. And the second, plastic volume changes when plastic is heated or cooled. The solution of the problem includes: the first, increase the injection pressure to force more material into the mould and reduce shrinkage. And the second, reduce wall thinkness, slow down cooling rate,…

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Plastic is a synthetic or semi-synthetic organic polymer. Plastic is used to produce a variety of household items such as trash cans, electrical pipes, bottles, tables and chairs, cups, plates, plastic bags, raincoats... and many other public products. Plastic has many outstanding properties such as being durable, light, hard to break and capable of deforming under the effect of heat and pressure. Has good heat resistance and insulation. Plastic is resistant to chemical corrosion, durable to all harsh weather conditions. Easily molded, pressed into many different shapes. Plastic does not react with air and water. it is very safe, use as food wrap, container,...

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There are 7 types of plastic most commonly used are PET, HDPE, PVC, LDPE, PP, PS, OTHER. Each type will have different characteristics and applications. PET resists rancidity, is easy to recycle and is used as food and beverage packaging. HDPE is hard, impact resistant, high temperature resistant; it is used to make baby bottles, lids, shampoo bottles, etc. one of the most appreciated plastic is LDPE. It is a flexible, odorless, transparent and recyclable plastic. It has the simplest structure of all plastics, making it easy to manufacture and cheap. it is used as plastic bags, dispensing bottles, various erecting boxes,...

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Check valves have many applications in life. To make a check valve, it needs to go through 6 different processes. The first is to shape the valve. The raw material for making one-way valve is iron that is cast into shape through a mold. Next, we grind the surface of the valve to be glossy, eliminating defects. then we proceed to drill: drill 4 holes into the 2 ends of the valve. the next step is stamping: stamping the two ends of the valve, then fixing it with screws, ... and finally spraying them with rust, checking the product. This is also a very important step to ensure that the product is made properly, without errors.

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https://drive.google.com/file/d/10YccbStyUpHV_T9-OOsit2Eq0zDa-XoZ/view?usp=drive_link

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https://drive.google.com/file/d/1Ev94TBLdPOC6oshr_Ssf5qgcyYesPeXs/view?usp=sharing

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cad and manual drafting both have distinct advantages and disadvantages. cad is software used on computers, manually edited, we draw and edit on paper, ... advantages: cad has the advantage of easier creation and correction, saving and reusing drawings easier with hard disk or CD, Easier analysis, simulation and inspection of 3D models, ... manual drafting has the advantages of easy operation, low drawing cost, users do not need to many skills, ... about the disadvantages, we see the advantage of cad is the disadvantage of manual drafting and vice versa. both cad and manual drafting have important roles in the field of application, electrical and electronic, mechanical... however society is developing day by day, changing the way of working is very important, We need to gradually switch from manual drafting to using cad.

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Gears are a very important part of a mechanical transmission system. It is made up of interconnected tooth grooves and usually follows a pair or pairs of gears that mesh together. Gears play the role of transmitting power, distributing fast or slow speed and torque. There are many different types of gears such as cylindrical gears, bevel gears, straight gears, etc. Each type of gear has different functions. Bevel gears are used to transmit rotational motion between two intersecting shafts. Worm gear and worm gear Used to transmit rotational motion between two crossed axes. The use of cylindrical gears to transmit rotational motion between two parallel shafts. Gears are commonly used in mechanical, automotive, cnc, ...

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There are two types of transmission: belt drive and chain drive. Both types of actuators have quite similar functions, are used to transmit motion from one shaft to another, motors, reducers, etc. belt drives are made of rubber or plastic. Continuous motion without lubrication. however it is easily affected by weather conditions. Belt drive has quite high technical requirements, low working efficiency but low noise. Chain drives are made of metal such as iron or steel and need to be lubricated regularly. When working, it often causes noise and vibration, but the working efficiency is very high. Chain drives are susceptible to atmospheric influences, are prone to oxidation and require regular lubrication. both chain drive and belt drive are very important in mechanical, automotive,...

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Coupling is quite important in work. Coupling be divided in to Rigid coupling and Flexible coupling

The Rigid coupling contist of steeve-style, the purpose of hold the shaft in perfect alignment. We can used align the shaft with eath other perfectly

The flexible coupling contist of beamcoupling. We can used accommodate a lignht misalightment. It is used when there is an offset. It is help reduce noise and vibration

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https://drive.google.com/file/d/106c-4zXvsUN9A_zU_9LjLFKAaTH4Fo9G/view?usp=drive_link

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https://drive.google.com/file/d/108zmviDodB52O6-FYOsB3UwH4Gqf4LJc/view?usp=sharing

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The bearings be diveded two kinds: Journal bearing and rooling contact bearing

The journal bearing have no rolling parts. The shaft rorates inside a lubricated sleeve instead. It is used roller to support load

The rolling contact bearing contist of kinds: ball, straight, tapered roller and thrust roller. The ball bearing used specical roller to support radial and axital motion:

_ If you used alignment rollers to support radial movement. You should use straight rollers bearing

_For tapered roller bearing, it is use to support radial forcus and moder thurst forces

_ The thurst roller bearing use roller to support thrust motion