Lesson video

Hi, my name's Ben and welcome to lesson two of this year five computing systems and networks unit all about sharing information.

Today we'll be looking at how computer systems and humans interact with each other.

You'll need somewhere quiet free of distractions a pen and a piece of people will be useful.

So when you're ready let's get started.

Here are the objectives for this lesson, so overall in this lesson you will recognise the role of computer systems in our lives.

In doing that you'll identify tasks that are managed by computer systems. Will then look at how human elements contribute to a computer system and finally, we'll look at a particular computer system and explain the benefits of it.

We'll begin by reminding ourselves of what a system is.

This is something we looked at in the previous lesson at both of the beginning and at the end of the lesson.

So of course a system is a number of things parts, components, or people that work together to complete or perform a task.

And we'll begin today by looking at another system which you might be familiar with.

Have a look at the picture on the screen.

What do you need to do to safely cross the road here? Pause the video and note down any ideas you have.

This is an example of a Puffin pedestrian crossing.

On a Puffin pedestrian crossing there's more than just buttons and lights.

Have a look at the picture on this slide what do you think it is showing here? Again pause the video and note down any ideas you have.

What you have here is a set of sensors.

So these sensors on a Puffin pedestrian crossing can detect people by the crossing, detect people on the crossing and also detect cars.

And then in the next slide will have a look at how that works.

Of course this is an example of a system.

This is an example of how the sensors on a Puffin crossing are set up.

So if we look at the lights on the right hand side of the picture we can see there are two sensors underneath the top set of lights.

The sensor on the left is looking at to see if there's anybody on the crossing so it will pick up and sense if anybody is in this space here and the sense on the right is looking to see if there is anybody waiting to cross so we'll pick up if there's any one standing on the pavement here.

On the left hand side there's two similar sensors so we've got one looking for people waiting to cross and another looking for anyone who is on the crossing.

Finally, there are two more sensors one on each side and they are looking to see if there is any traffic or cars approaching the crossing.

So they're pointing out this piece of road here and slightly hidden this piece of road here behind wherever that sensors looking as well.

So there's three sensors on each side of the Puffin crossing.

How do you think they make the crossing more effective? Just pause the video and have a think about that for a couple of minutes.

On your handout sheet I would like you to complete the sheet which compares the Puffin crossing which has sensors with a more traditional timed crossing which doesn't have those sensors.

Pause the video and complete your task.

Let's look at the similarities and differences between a timed crossing and a sensor crossing.

So starting from the top, both the timed crossing and the sensor crossing will allow pedestrians to stop the traffic to help them cross safely.

So they both have a button which you can press as a pedestrian and we'll look at how the timed crossing and the sensor crossing handle that differently as we go through.

They both also give pedestrians time to cross the road.

So that makes it safer for pedestrians to use as a crossing.

And here's where some of the differences start to come in so the third line stops the traffic for no longer than necessary.

Well on a timed crossing, the traffic will always be stopped for a fixed interval whereas on a sensor crossing, it will only stop the traffic for as long as is necessary.

So once the crossing is clear of pedestrians it will let the traffic flow again.

Similarly for the next one adapts to pedestrians walking at different speeds.

If somebody is walking across the crossing particularly quickly or slowly the crossing will sense that and either delay the change of the lights back to green for the traffic or advance it slightly quicker.

They both indicate when it is safe to cross and when not to through the red and green indicators on the crossing.

A sensor crossing is clever in that it will if someone presses the button and then walks away it will not stop the traffic because the sensor which is looking at the footpath will see there is nobody waiting to cross even though the button has been pressed and will not change the lights for the traffic meaning that the traffic can flow more freely.

On a timed crossing, if someone presses the button the lights will always eventually change even if they press the button and walk away 'cause there's no senses seeing if they're still there.

The final two are both unique to a sensor crossing so on a sensor crossing you need to stand in the right place for the lights to change if you're not in the right place on the footpath it will not sense or detect you so the lights won't change.

And finally, when there's a lot of traffic the lights may wait for a few seconds before changing to let traffic pass.

That again is a feature of a sensor crossing.

So it can pick up if the road is particularly busy and if it would be beneficial to let more traffic through before the lights change.

On a timed crossing that interval is fixed so the button is pressed and then after a set number of seconds the lights will change.

So there's some of the similarities and differences between a timed crossing and a sensor crossing.

So we've looked at an example of a digital system in the Puffin crossing.

What I'd like you to do now is have a look around you and see if you can find any other examples of digital systems. That could be in your home or it could be around where you live in shops or other places.

So have a think about where else you might find digital systems. Pause the video while you think about that.

Here's a couple of examples you may have come up with.

So a really interesting digital system it can be found in a library.

It manages the books being lend out where they are due back, which books are in the library the location of books all sorts of things are managed by a digital system in a library.

In the middle we have an airport departure board.

So this shows you where flights are going, what time they're leaving, whether they're leaving on time and which terminal they're leaving from.

You may have seen similar departure boards in train stations or bus stations.

And finally, on the right hand side one that most people should be familiar with is a supermarket.

There are digital systems all throughout supermarkets managing things like stock control, pricing, the tills, the door entry system so there's lots and lots of digital systems in a supermarket.

Did you find any of those three digital systems or any others? For the rest of this lesson, we're going to be looking at a particular type of digital system and that's one that you would find in a catalogue store.

So by a catalogue store I need something like Argus.

So the kind of shop where you choose your items off of a tablet or from a catalogue and place your order and then your order is picked from the warehouse and delivered to you at the counter or the collection point.

On your handout you've got a list of steps for each of those three points so the order point, the warehouse and the collection point.

I want you to imagine you're running the catalogue store and place the list of steps for each of those in the correct order.

So at the moment on your handout, they're in the wrong order and I want you to put them in the right order.

So if you could pause the video now and complete that task.

Here is the order of the tasks in this process.

So starting from the order point, first of all, the customer looks at the items they want to buy it on a tablet so searches for them on a tablet, the tablet will show them which items are in stock and available and how much they are so the price.

The customer can then choose on the tablet, which items they want to buy.

When they've done that they can pay for their items and that now becomes their order and a receipt is printed out showing the customer what they have ordered.

And at this point the order then is sent to the warehouse.

So that brings us onto the second stage the warehouse.

So they receive the order from the shop floor and the computer will show staff where the items are in the warehouse.

So that means then the people that work in the warehouse can find those items quickly and pick them from the shelf.

They can then on the computer mark off those items as picked so they're no longer in the warehouse because they've been picked for the customer.

The computer keeps an up-to-date stock-list based on this information and then the items are taken to the shop floor.

From the shop floor to the collection point.

And then finally at the collection point the ordered items arrive at the collection point ready for collection.

On a screen or a display it will say order ready for collection at the collection point so that the customer knows.

A receipt is then printed off showing the items ordered and that's given to the staff.

They then take off the items against the customer's receipt, give the items to the customer and then mark them as collected on the computer.

So that's the whole process right from the customer looking at what they want to buy at the order point to where they collect it at the collection point.

In the catalogue store system, we've identified lots of different parts.

Some of those parts are completed by people and some of them are completed by computers.

And some of them are a combination of people and computers.

What I'd like you to do now is have a look at the ordered steps which we'll look to in the previous slide and say whether you think those steps are completed by people, computers, or both.

You can just mark with a P for people or C for computer for each step.

So pause the video while you complete that task and then we'll come back and have a look at which steps are completed by people, computers or both.

So which tasks are completed by people and which are completed by computers.

So again let's start from the order point.

So at the order point a tablet is used to look at items to buy so that's both people and the computer.

So the people are looking at the tablet the items on the tablet.

The tablet shows the what's in stock and shows the price of that's a computer based task.

And then the customer chooses what they want to buy on the tablet so again using that's people and the computer involved in that part of the system.

The customer pays for the items this is their order so the customer does that themselves that's people but they pay for the items on the tablet so that's the computer.

And then the last two stages are both done by the tablets so both computer based.

The receipt is printed and the order is sent to the warehouse.

So at the warehouse stage, there's quite a lot of computer involvement so first of all, the order is received from the shop floor that's sent from one computer to another the computer shows the stuff where items are in the warehouse, obviously that's computer based.

And then the human element comes in where the ordered items are picked from the shelf.

I say human element in some really big warehouses that's actually done by robots so that could be computer-based.

In this instance, we'll assume it's people based.

Then again in the warehouse the items are marked off as picked so that would be the person who's picked the item marking it off as picked on the computer so both people and computer.

The warehouse stock-list is kept up-to-date on the computer and finally at that stage the items are taken to the shop floor for collection so that's people.

At the collection point finally, we've got ordered items arrive at the collection point ready for collections that's people-based.

A message will be displayed at that point saying order ready for collection so the computer will do that.

A receipt showing items is given to the staff so the receipt is printed off by the computer but maybe given to the staff by people.

The items are ticked off as ready for collection on the customer's receipt so that's done by a person.

Handed over at that stage again by a person and then finally marks as collected on the computer so the person working in the store marks them as collected and they do that on the computer so that's people and computer.

So that's where people and computers are involved at each stage in this rather complex system.

Let's have a look at three situations which might happen in a catalogue store.

We're then going to decide whether that would most influence the order point the warehouse or the collection point part of the system.

So the first situation here is a customer returns an item that cannot be resold.

Have a think about which step that would most influence and then we'll look at the answer.

So this would influence the warehouse.

The stock level in the warehouse will need to be updated so the item can be resold.

Next the price of an item changes does that affect the order point the warehouse or the collection point most? Pause there for a second while you think about that one.

And we'll look at the answer now.

So that would influence the order point because the price would need to be shown on the tablet at the order point.

And finally an item cannot be found in the warehouse does that influence the order point the warehouse or the collection point? Again we'll pause for a second while you think about that one.

and here's the answer for that one.

So that most affects the collection point because the collection point will need to be informed so the customer can be advised that their item cannot be found.

For the final part of this lesson we're going to think about how a system helps us.

so early we look to the Puffin crossing.

That system includes sensors which help keep pedestrians safe but also helps keep the traffic flowing at a good rate.

Now we're going to think about how the catalogue system helps us.

So we're dividing that into two parts so how does it help the customers and how does it help the people who work there.

On your handout I'd like you to note down any ways in which you think the catalogue store system helps the customers and the people that work there.

Pause the video to complete your task and then we'll have a look at some of the ideas you could have come up with in a couple of minutes.

Here are some of the ways the system can help the customer and the store workers.

So looking first at the customer.

So the first thing that is really useful for a customer is the system will show if an item is in stock.

There's no point ordering an item that isn't in stock so that's really useful.

It shows the price of items so customers know how much they're going to be paying it makes the ordering quick and easy and it provides them with a printed receipt.

Those are all really helpful parts of the system for the customer.

For the store workers orders are automatically delivered to the warehouse they don't have to find them from the shop floor they come through automatically.

The system will show them where things are in the warehouse they don't have to go looking around for ages for them it will take them straight to the right place.

It keeps stock lists up to date so they know where they need to order more stocks if they run out of a particular item that can order more.

It tells them when orders are ready and also similar to the customer it prints receipts which is really useful for the store workers to keep track of what's been ordered.

Did you find any other ways in which the system helps the customer and the store workers? I hope you've enjoyed taking part in this Oak National computing lesson.

We'd love you to share some of your work with us.

If you'd like to please ask your parents or carer to share your work on Facebook, Instagram or Twitter tagging @OakNational and #LearnwithOak.