POSTDOCTORAL POSITION. Geometry and Graphics Group (GGG)

*POSTDOCTORAL POSITION. *

Geometry and Graphics Group (GGG)

Universitat de Girona

Salary 25,750 euros/year

Contact: xavier.pueyo@udg.edu 

Deadline: As soon as possible. Better before July 28^th .

* *

*RESEARCH SUBJECT.*

The scientific motivation is mainly to expand the application range of
inverse natural lighting models. More precisely, this project aims at
bringing efficient inverse rendering principles from computer graphics
into CAAD field in order to manage architectural design problem.

The inverse lighting simulation computes opening from lighting
properties. This is an inverse geometry problem as we are looking for
scene geometry. However this geometry also defines daylight source
visibility, so this problem could be seen as an inverse lighting
problem, source positioning or emittance research. This problem has been
addressed as an inverse geometry problem or an emittance research
problem (inverse lighting). Therefore this problem is not clearly
identified in the inverse rendering framework as an inverse geometry
problem or an inverse lighting problem. Moreover, the realization of the
architect will depends on his capacity to translate his lighting
intentions in lighting parameters. Subjective lighting descriptions
allowed by current CAD interfaces do not satisfy designers. Current
Inverse lighting model cannot take into account all parameters in order
to aid architectural design at the early stage of conceptual design.

Reducing the energy use of buildings without compromising the indoor
environment and services is the key challenge for Europe.”
(http://www.managenergy.net/buildings.html) Energy savings are a
worldwide challenge and the European Community defined energy saving as
a critical goal. Building energy consumption in Europe represents 40% of
the total energy use. The energy use of buildings comes mainly from
space heating, air conditioning, water heating and lighting. The
electrical energy used to light buildings represents 19% of total
consumed electricity. As a comparison this is 70% of the energy consumed
by passengers vehicles.

User comfort is an essential issue. When related to lighting, the user
comfort can be seen as the lighting ambience. It has been proven that
the human circadian cycle is influenced by lighting. The lighting
ambience is a way to characterise the functionality and the quality of
lighting. The lighting functionality is defined as light levels in lux,
avoiding glare and minimum contrast. The lighting quality have a
physiological influence, natural lighting is good for health, as well as
a psychological influence, natural lighting assist a feeling of
well-being. As a consequence, a good lighting ambience which merge
functionality and quality can increase productivity.

In order to achieve a sustainable architecture, designers cannot afford
to take into account the natural light influence on user comfort and
energy consumption. The key issue is to have an idea about this natural
light influence in the early stages of conceptual design, when buildings
are not completely defined and when the designer can still drive his
design towards a sustainable one without a loss of time and energy.

We aim at developing an inverse natural lighting model adapted to
architectural and urban design, and able to manage extended and dynamic
light source of natural lighting, complex designer's intentions, light
transformations through opening (shading devices, glass properties) and
light reflections.