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Hello, welcome to the Elements de Géomatique course.

This is a basic course for civil engineering students,

as well as for other people interested in topography,

in geographical information systems

and in the gathering of data for spatial references.

This introductory part is composed of the following elements:

some definitions an introduction with examples,

what is geomatics?

A description of the course objectives, course syllabus,

as well as the didactic approach of the different educational resources

that are at your disposal

and finally the evaluation methods for the course.

Geomatics! Geomatics is a relatively new term

that is composed of <i>geo</i>, Earth

and <i>matics</i>, which comes from informatics.

So, it's ultimately information technologies

in service of geography and all the data

that affect the spatial domaine.

Among the different geomatics disciplines

we can already mention land surveying

which is a set of methods that allow you

to obtain geographical data from the ground or from an airplane.

There's also the discipline of geodesy,

which is the science of the study of the shape and geometry of the Earth.

There are also other disciplines related to the gathering

such as, for example, photogrammetry as remote sensing.

This methods are image based and permit the observation of earth

and also a measure of objects on the territory.

It is finally all the elements that permit the representation

of geographical objects with cartography methods,

3D visualizations

and management systems called

"Geographic Information System"

which is usually just called GIS.

In order to illustrate what geomatics is, we will take two examples.

A first example in natural terrain is the Arolla glacier.

We are interested in measuring the retreat of the glacier's front.

On this image you can see

the typical scenery with the front of the Arolla glacier here

and this part in front here characterizes the moraine

and a watercourse also,

because it's summer and the glacier is melting.

If we get closer to the glacier, we can see the elements that interest us

In this case, here the measure of a series of particular points

that I will connect here with a line

and that effectively describe the glacier's front.

You can see a stake here with a specific measuring point

so the objective here is to measure, with surveying methods,

in this case, a theodolite or GPS. We will measure particular points

in coordinates, so that we can document the observed state in this year

and view its evolution over time.

If I now look at up the points on a map,

I have on this example here my coordinate system

with the different time periods, here,

between 2000 and 2002, I have here the glacier front for the period of 2002,

and I have in the upper part the glacier front for the period of 2000.

So we can see the separation of the two front lines.

More concretely, if I come here on an enlargement of the zone

and look at what is happening here between the two periods

and I have a difference, that I can measure here, planimetric of about 15m

as the annual regression of this glacier tongue.

What is more interesting compared to the map, is to transfer these elements

to the terrain and for this, we will undertake a surveying process

that's called implantation.

Impantation consits of, starting with coordinates

of the previous state, if I take my coordinates of the previous year here,

and I can implant these points

it means, move from my collection of XY coordinates

to a reality on the field.

This reality is represented by a set of stakes planted on the field

at the location at which the front line

of the previous year was effectively measured.

And if I now look at the current front line

well, there is a discrepancy here in life size, in actual size,

you can see here a student's height.

And we can effectively see these 15m of discrepancy that we have in this example.

Another example related to cartography.

You have a territory here that is well known to EPFL students:

It's our campus grounds, but in 1953.

So you have here the national map with the area of EPFL,

which at that time wasn't anything but fields and crops.

On this map, you can find the soil cover

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And you can also find the different communication lines:

the streets and country roads.

If I move to a subsequent time period, to 1980, which corresponds

to the first construction phase of our campus.

You can see the evolution the way it was mapped in 1980

with a form of urbanization that's starting to develop

around the school.

If I now move to the state, I'll say more recent, 2011

where we find our campus the way we know it.

You can see this strong urbanization and the map effectively seves

as a support to document the history

of our territory's evolution.

It's a valuable document that the Géomatique uses

to understand the dynamics of the evolution of our territories and landscapes.

Géomatique, what is finally needed to document

the evolution of our natural and built environment?

We have talked about the glacier example, of a repository of coordinates.

So the first thing that needs to be used effectively is

a coordinate system, if possible in 3 dimensions

with planimetrics and a vertical altitude component.

Next, we will come to measure objects in the world surrounding us.

that we'll refer to as the "real world".

We will come with a certain number of instruments which are for example

surveying instruments that are terrestrial

or today with the help of satellites such as GPS for example.

And we will be able to measure this real world, measure objects in this world.

Next, we come to a section, I'll say more informatic.

I'll draw a little screen here

With an information system stored in a database.

So, we have here all the methods of managing and representing

spatial information.

Here is a little about the elements that are required to document this evolution.

We can see them on this figure with the different pillars

that are the acquisition of spatial reference data.

Next all the their processing, their representation, whether it's

on the maps or on tridimensional models

and finally a diffusion via different Internet channels

that are known today with different geo data servers

available to everyone.

What are the objectives of this geomatics cours?

First of all, it's about giving an overview of geomatics

And the different measurement techniques

Next, about presenting methods utilized for the acquisition,

the representation and management of spatial references data.

If we take an example here of an engineering project,

we will first plan interventions, prepare a project,

for this we need field operations

where we model objects, we will make the aquisition

with topometric methods.

Next, we will return to the office with the cartographie operations,

of representation. We'll have to create plans and maps for the making of the survey.

And finally, we will go to into the field to realize the project

with implementational operations.

Once the project is completed, we will do a survey which will be archived

for the purpose of conserving documents.

What is the content of the geomatics course?

First of all, we'll give an introduction of geomatics.

Next we have the basics of geodesy with all the definitions

the coordinates systems.

Next, a section dedicated to cartographic representations

and afterwards we have the different methods of acquisition.

We'll concentrate on the geometric level, on the utilisation of theodolites

for its orientation and its lifting operations.

Next there are distance measurements, also related to the levées

and afterwards we tackle the spatial surveying with GPS.

Finally, we process the numeric terrain model,

its modeling and its utilisation for altimetry questions.

The didactic approach proposed in this course is

between the basic sciences that you have

in the different engineering schools.

These are mathematics, physics, algebra, informatics

and finally engineering sciences,

namely construction, civil engineering, development, environment.

It's a little bit at the interface between the disciplines.

And in this course we will put an emphasis

on modeling concepts independent of technologies.

On the level of basic knowledge, it's not necessary to have

in-depth knowledge. It's a first year course.

On the other hand, it's necessary to have some knowledge

of geometry, algebra and trigonometry.

These are the main equations that we will use

for the topometric methods.

An important point in this approach is the rigor in the calculation work.

Concepts of precision, of reliability are fundamental

in geodesy, in topometrics.

So we will focus on these issues in different calculation exercises.

In terms of pedagogic resources, you have an entire series of course

videos that explain the principles and methods a little bit

with some sets of questions that allow you to reflect

the problematic in a video sequence.

Aside from that, we have an entire series of hands-on videos,

because surveying and geomatics happen in the field.

And because of this, we have a video series that illustrates the methods

in a more concrete context.

This field aspect is important for the course.

You also have a quiz series, with multiple-choice questions

or with numeric answers when it's about calculations.

As another pedagogic resource you can find the handouts,

"éléments géomatiques" that are for sale for courses here at EPFL.

But for people who are taking this course from far away there are

pd files for each lesson that resume the principal chapter

that is discussed in the module in question.

You also have some calculation tools online on the internet,

to help you a little in approaching topometric calculations

And finally, you have topometric calculation exercises

as well as the use of some software tools

for the representation of spatial data,

for the calculation of numeric field models.

How will the course evaluation be conducted?

It will be done for each lesson, for each module,

with a quiz series and a main exercise,

which will often be a calculation exercise or data representation

with spatial reference

and at the end of all the modules and lessons you will have a certain number

of quizzes that will be evaluated and graded and a certain number of exercises.

You'll have a weighting for the final grade

with 40% for the quizzes and 60% for the exercices.

This will give you the final grade for the module.