IT · Semester 1 · Chapter 1 · Book pp. 1–27
Let's Solve the Problem
มาแก้ปัญหากันเถอะ
Every chapter of this book follows one real problem: the rubbish bins near the school canteen keep overflowing. Two students, Non (นนท์) and Namwan (น้ำหวาน), solve it in two different ways, with help from the Doctor (ด็อกเตอร์). In this chapter you learn to understand a problem properly before you try to solve it.
Learning objectives จุดประสงค์ของบทเรียน
By the end of this chapter you can:
- Analyse a problem situation and write a summary of the problem scope.
- Gather data that relates to ways of solving the problem.
In this chapter: 1.1 Technology for managing the environment · 1.2 Analysing the problem situation · 1.3 Gathering data to solve the problem
Apply it: traffic jams — what is the real cause?
Traffic jams are a big problem in cities. They pollute the air, they are noisy, and they affect people’s health. The book shows five possible causes:
- There are few public transport choices, so people use their own cars.
- Drivers break the rules: they cut in and change lanes, which causes accidents and slows everyone down.
- Traffic is badly managed: the lights do not match the traffic, signs are unclear, and roads are dug up at rush hour.
- There are many cars but not much road.
- People like convenience and do not want to use public transport.
To solve a problem like this, you first have to find out what really causes it. Then you can choose a solution that fixes the real problem and keeps working in the long run.
📖 Review before you start
Community K has a problem: people throw rubbish into the canal. There is so much that the water smells, animals live in it, and it spreads disease. How can we help them? In M.1 you learned the engineering design process. Use it here to solve the problem step by step, starting from your own ideas.
Environmental problems ปัญหาสิ่งแวดล้อม
For many years Thailand’s population has grown. Towns have spread, the economy and industry have grown, and we use more and more natural resources. Some resources run out, and pollution increases. Environmental problems come from people, and also from nature, so people build technology to solve them.
Problems caused by people
More people and bigger towns bring new technology to meet their needs, but also rubbish and wastewater from factories and homes. When these go into rivers and canals, the water smells, germs breed, and people get ill.
Smoke from cars and factories harms our breathing and causes acid rain. It also pollutes soil and water with chemicals.
Problems caused by nature
| Natural event | What it does |
|---|---|
| Wildfire | Some start naturally, when strong dry winds rub branches together. The smoke and dust pollute the air. |
| Flood | Damages homes, property and farms, and spreads diseases: athlete’s foot, conjunctivitis, dengue fever, diarrhoea, food poisoning and cholera. |
| Earthquake | Caused by moving plates of the Earth’s crust. Buildings collapse and people lose homes and food. It also changes the land and the plants and animals living there. |
| Volcano | Magma, ash and gas pour out and pollute the air. An eruption under the sea can cause a huge wave, a tsunami. |
Many countries are trying to reduce or fix these problems. Groups such as Greenpeace campaign to protect the environment, and carbon footprint labels on products help people pick the ones that release the least greenhouse gas, which causes global warming. People also invent new technology to solve environmental problems.
🧑🔬 The Doctor asks
What technology do we use today to solve environmental problems?
1.1 Technology for managing the environment เทคโนโลยีในการจัดการสิ่งแวดล้อม
Today we use technology to treat wastewater, reduce air pollution and manage rubbish.
Treating wastewater
Factories that make electronics and batteries release heavy metals such as lead, tin, mercury, cadmium and chromium. In the body these damage the nervous system and can cause cancer. They are especially dangerous for animals that live in water.
A microbot is a robot smaller than a human hair that soaks up lead from factory wastewater. Its outer layer is graphene, which absorbs the lead. Inside is platinum: when hydrogen peroxide is added to the water, the platinum breaks it down and releases tiny bubbles out of the back, which push the robot forward. A magnetic field steers it. More: ipst.me/9123
Reducing air pollution
A cyclone separator removes dust particles of about 10–40 microns from dirty air before it is released. It uses centrifugal force: the air spins, so the heavy particles are flung to the wall and fall to the bottom. Cyclones are used where there is a lot of dust, such as sawmills, animal-feed factories, rice mills and metal-grinding works.
Managing rubbish
Rubbish comes from food, farm waste, plastic bags, paper, glass, packaging and chemicals. To make it easier to manage, Thailand’s Pollution Control Department sorts it into four bins:
| Bin | Type of rubbish | Examples | What happens to it |
|---|---|---|---|
| 🟦 Blue | General: hard to break down, not worth recycling | Snack bags, foil sachets | Sanitary landfill |
| 🟨 Yellow | Recyclable | Glass, paper, plastic, metal | Recycled into new products |
| 🟩 Green | Wet: breaks down easily | Food scraps, vegetable and fruit waste | Compost, biogas or animal feed |
| 🟥 Red | Hazardous: must be collected separately | Spray cans, light bulbs, batteries | Sent to a plant that disposes of it properly |
A landfill must have a waterproof lining so the liquid from the rubbish does not soak into the ground water. The lining must also hold the weight of the rubbish. Rotting rubbish produces methane, which burns, so the landfill needs gas vent pipes, and the gas can be used to make electricity. More: ipst.me/9125
💭 Think about it
Besides the examples above, what other environmental technology have you seen or read about online?
🛠️ Activity 1.1 · Survey the environment at school
In groups, survey the environmental problems in your school or community. Draw a mind map showing as many problems as you found.
1.2 Analysing the problem situation การวิเคราะห์สถานการณ์ปัญหา
Stating the problem clearly is the base for setting goals that match the real problem. Collecting the details helps you solve it to the point. One useful technique is to ask 5W1H questions:
| Question | Asks |
|---|---|
| What | What is the problem? |
| Who | Who does it affect, and who causes it? |
| Why | Why does it happen? |
| When | When does it happen? |
| Where | Where does it happen? |
| How | How can we solve it? |
The school’s problem: overflowing bins
A school has many environmental problems: bins overflowing with rubbish, wastewater from the canteen, and smelly food waste. Rubbish is the most common. Even though the school already has separate bins for each type, they still overflow.
| Problem | Cause |
|---|---|
| 1. Bins overflow | A lot of rubbish, not enough bins, and nobody empties them often enough. |
| 2. Bins smell | Wet rubbish is left in the bins. |
| 3. Flies swarm round the bins | The smell of the wet rubbish attracts them. |
💡 Did you know? Rotten-egg gas
Hydrogen sulfide comes from rotting rubbish, wastewater and dead animals. Breathing 100 ppm (parts per million) for 30 minutes can kill. At 1,000 ppm, two or three breaths kill at once, because the gas stops oxygen reaching the brain.
The overflowing bins cause the other problems (the smell and the flies), so they must be solved first. Here is the 5W1H analysis:
| 5W1H | Overflowing bins |
|---|---|
| What | There is so much rubbish that it spills out of the bins. |
| Who | Everyone in the school who throws rubbish, including canteen sellers and the students who buy from them. |
| Why | Too much rubbish; the bins are too small; the rubbish is bulky and takes up space. |
| When | All day, but most at the lunch break. |
| Where | The bins by the seating area next to the canteen. |
| How | Reduce the volume of the rubbish so the bins hold more; reduce the amount of rubbish. |
Two students, two problem scopes
Non and Namwan look at the same situation. Non will make a product (ชิ้นงาน); Namwan will use a method (วิธีการ).
💡 Did you know? Open the cap first
With the cap on, the air inside pushes out on every wall as hard as the air outside pushes in, so the bottle is hard to crush. Opening the cap lets the air out, so only the outside air pressure and your own push act on it.
| Non (product) | Namwan (method) | |
|---|---|---|
| Cause he or she found | Empty space between items, especially bulky empty plastic bottles and cups. | Too much plastic packaging is used. |
| Problem scope | Find a way to crush plastic bottles and cups in the bin, so there is more room for everyone’s rubbish, especially at lunch. | Find a way to reduce plastic rubbish before it reaches the bin. The school already sorts its rubbish, but the plastic still overflows. |
🛠️ Activity 1.2 · Set the scope of the problem
From your survey in Activity 1.1, choose one problem and give your reasons. Analyse it with 5W1H, then write its problem scope.
1.3 Gathering data to solve the problem การรวบรวมข้อมูลเพื่อแก้ปัญหา
Once you have the problem scope, gather data and ideas that could lead to a solution. First decide which topics to look up. That saves time and makes searching easier.
Namwan wants to reduce the amount of rubbish, so her topics are:
- The cause of the overflowing bins
- A survey of the types of rubbish
- How students throw their rubbish away
- Ways to reduce each type of rubbish
💭 Think about it
If you were Non and wanted a way to crush the rubbish, which topics would you look up?
Ways to gather data
Search reliable websites, visit and survey the real place, do science experiments, ask experts, and read documents, articles and research. Then develop or adapt what you find to solve your problem.
When you search online, use a clear, specific keyword. Searching only “rubbish” gives very broad results that are not about reducing it. Searching “ways to reduce rubbish” gives results that match what you need.
Is the source reliable?
- The author or agency is clearly named, with a date, and the source of the data is shown.
- Agencies should be the ones directly responsible for that topic. People should be experts that others accept.
- Compare data from several sources.
- Always cite where your data came from.
💡 Did you know? Citing a website
Give the author, year, title, the date you looked it up, and the address. For example: IPST. (2010). Seasons on Earth. Retrieved 2 October 2018, from http://scimath.org/article-earthscience/item/1466-season-with-the-world.
💭 Think about it
You want to find out what causes global warming. Which keywords would you use? In groups, search for real, then compare which group found the data fastest and closest to the topic.
Using many subjects at once
Some problems need knowledge from several sciences. Thailand’s artificial rain (royal rainmaking) project, made to end droughts, uses chemistry and meteorology together.
🛠️ Activity 1.3 · Choose your data topics
List at least 3 topics to gather data on, linked to your group’s problem, and say where you will look for each one.
What Non found: three ways to crush rubbish
Way 1 · A lever
A crusher is fixed to the edge of the bin. Pressing the handle pushes a plate in the middle down onto the rubbish. The further from the pivot you push, the less force you need. This uses levers and moments: the moment of a force is M = F × L (force × its distance from the pivot).
You push with F1 at distance L1. The rubbish pushes back with F2 at distance L2. When the lever balances: F2 × L2 = F1 × L1. Because L1 is longer than L2, F1 can be smaller than F2, so the crusher needs less force from you.
🧮 Try it: lever calculator
Way 2 · A scissor mechanism
A smart bin runs on a battery charged by solar panels. A sensor checks how full it is. When the rubbish reaches a set level, a scissor mechanism stretches down and crushes it, then folds back. When the bin is about 85% full, it sends a message by smartphone to the collector. It holds up to 8 times as much as a normal bin, which saves time and money.
Way 3 · Hydraulics
Rubbish trucks use hydraulics to move the scoop and press the rubbish into the tank. Liquid pressure is P = F ÷ A. Pushing the small piston (area A1) with force F1 makes a pressure F1 ÷ A1 that spreads through the liquid to the large piston (area A2): F1 ÷ A1 = F2 ÷ A2. If A2 is bigger than A1, F2 is bigger than F1, so a small push lifts or presses something heavy.
What Namwan found
Many organisations run school rubbish projects, such as Zero Waste School, the WWF Eco School award, and EGAT’s Green School project. From her search and survey she found:
- Cause: the bin is next to the canteen. After lunch, students buy drinks in plastic cups and throw the cups in the nearest bin.
- Type of rubbish: plastic bottles and plastic cups.
- Behaviour: even when that bin is full, students still throw rubbish into it.
- Ways to reduce it:
Way 1 · Rules for shops and students
- Shops stop selling single-use plastic cups and use washable cups that students return after drinking. This also builds tidy habits: students help clear their plates and do not take food out of the canteen.
- Students stop using plastic straws and drink from the cup.
- Students bring their own cups.
Way 2 · Leaflets and posters
Teach people about types of rubbish and how rubbish harms people, animals and the environment, and make them want to reduce it. Put posters where people often throw rubbish or where many people pass.
Way 3 · A school recycling bank
Students join as members and deposit recyclable rubbish. Student staff sort and weigh it, work out its value at prices agreed with a scrap shop, and record it in the member’s book. The money becomes a fund for education and pays dividends to members.
Non’s and Namwan’s data came from many reliable sources, used several sciences, and gave several possible solutions. A solution does not have to be the first one you find. Next, you will compare the ideas and choose the one that suits your conditions and resources best.
🛠️ Activity 1.4 · Gather data
Gather data on the topics you chose in Activity 1.3. Write a summary of each solution you found, with its source and the date you looked it up.
💭 Think about it
Apart from Non’s and Namwan’s ideas, what other ways could solve the rubbish problem at school? Think it over in your group.
Chapter summary สรุปท้ายบท
- Analysing the problem situation shows you what really matters: the key points of the problem, its conditions, and the data that goes with it.
- Writing that analysis as a problem scope makes the problem clear and sets the limits for finding a solution.
- Gathering data means looking for a suitable way to solve the problem. The data may come from several sciences and several kinds of search, but it must come from reliable sources, and you must say where it came from.
🎤 End-of-chapter activity · Present your analysis and data
Present what you did in Activities 1.1–1.4 to the class. Let the other groups ask questions and give suggestions.
Mini-quiz
Source: IPST (สสวท.) Basic Science and Technology textbook, Technology (Design and Technology), Grade 8 (M.2), Chapter 1. Figures are from the textbook; text translated and adapted by Guru Jazzy.