Conference PaperPDF Available

Genesis of the CityGML Energy ADE

  • September 2015
DOI:10.5075/epfl-cisbat2015-931-936
  • Conference: CISBAT 2015
  • At: Lausanne, Swiss
Authors:
Romain Nouvel at OTEIS
Romain Nouvel
  • OTEIS
Robert Kaden at Fachhochschule Erfurt
Robert Kaden
Jean-Marie Bahu at wpd solar
Jean-Marie Bahu
  • wpd solar
Jérôme Henri Kämpf at Idiap Research Institute
Jérôme Henri Kämpf
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Abstract and Figures

The current climate and environmental policy efforts require comprehensive planning regarding the upgrade of the energy supply and infrastructures in cities. Planning comprises e.g. the determination of locations for new power generating facilities like photovoltaic, geothermal and decentralized combined heat and power stations, the widespread introduction of e-mobility solutions and hence the grid development as well as large-scale energetic building refurbishments. A holistic approach integrating extensive complex information is essential for the strategic planning of the different measures. In order to establish interoperability and data exchange between the different planners, stakeholders, and tools, an open information standard is required. To answer this need, an international group of urban energy simulation developers, geo-information scientists and users from 11 European organizations is developing an Application Domain Extension (ADE) Energy for the OGC open standard CityGML. This paper presents the collaborative development of this new open urban information model, including its genesis, objectives, structure and next planned steps.
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GENESIS OF THE CITYGML ENERGY ADE
R. Nouvel
1
; R. Kaden
2
; J-M. Bahu
3
; J. Kaempf
4
; P. Cipriano
5
; M. Lauster
6
; J. Benner
7
; E.
Munoz
8
; O. Tournaire
9
; E. Casper
10
.
1: HFT Stuttgart, Germany / 2: TU Munich, Germany / 3: EIFER, Germany
4: EPFL Lausanne, Swiss / 5: Sinergis, Italy
6: RWTH Aachen University - E.ON Energy Research Center, Germany
7: KIT, Germany / 8: HCU Hamburg, Germany / 9: CSTB, France / 10: SIG 3D, Germany
ABSTRACT
The current climate and environmental policy efforts require comprehensive planning
regarding the upgrade of the energy supply and infrastructures in cities. Planning comprises
e.g. the determination of locations for new power generating facilities like photovoltaic,
geothermal and decentralized combined heat and power stations, the widespread introduction
of e-mobility solutions and hence the grid development as well as large-scale energetic
building refurbishments. A holistic approach integrating extensive complex information is
essential for the strategic planning of the different measures. In order to establish
interoperability and data exchange between the different planners, stakeholders, and tools, an
open information standard is required.
To answer this need, an international group of urban energy simulation developers, geo-
information scientists and users from 11 European organizations is developing an Application
Domain Extension (ADE) Energy for the OGC open standard CityGML. This paper presents
the collaborative development of this new open urban information model, including its
genesis, objectives, structure and next planned steps.
INTRODUCTION
Urban Energy Modelling and Simulation has seen a substantial development during the last
decade, boosted by two factors; the shift of the energy transition paradigm at the city scale
level, and the increasingly high computational performances reached by multi-core
microprocessors and Graphic Processing Units. In the past few years, international research
centres and private sector actors have developed specific algorithms and software solutions
(e.g. CitySim, UMI), which provides new digital methods for energy planning and decision
support. Decision makers, in municipalities, housing authorities, energy supply companies
and other stakeholders are just getting used to the enormous potential of them.
However, contrary to Building Energy Modelling, where a number of well-established
Building Information Model (BIM) standards (IFC, gbXML) serves as exchange support
between different tools and expert fields, allowing for high interoperability possibilities, no
comprehensively applicable model standard exists until now for Urban Energy Modelling.
Therefore, developers of new urban energy tools have created their own tailor-made data-
models, while municipalities and other urban information data administrators have their own
database structure to collect and manage urban information. As such, these models exist
without interoperability possibilities, necessitating that each new attempt at developing a
comprehensive Urban Energy Model begin from the ground up.
An open Urban Information Model standard namely exists to encode, store and exchange
virtual 3D city models and landscape models: CityGML [1], which is developed by the Open
Geospatial Consortium (OGC). This XML-based data model defines classes and relations for
the most relevant 3D topographic objects in cities (e.g. buildings, transportation
infrastructures, city furniture, water bodies) regarding their geometry, topology, semantics,
and appearance. In particular, the representation of buildings includes WallSurface,
GroundSurface, and RoofSurface as well as for the description of the roof shape, usage type,
number of storeys, construction year, and building height. A considerable asset of CityGML
is its flexible object modelling in different Levels of Details, enabling the virtual city model to
adapt to local building parameter availability and application requirements (see Figure 1).
However, since CityGML is an application independent information model, it does not
include specific energy-related elements naturally.
Figure 1 Building 2 of HFT Stuttgart, represented in the four Levels of Detail (LoD) of the
OGC standard CityGML (source: HFT Stuttgart)
With the CityGML concept of Application Domain Extensions (ADE), it is possible to
incorporate domain-specific entities which are not pre-defined in CityGML standard.
Concretely, an ADE is represented by an XML-Schema using a specific namespace (energy in
our case), interfacing with the CityGML base schema. The ADE concept supports two
different methods for extending the base standard, detailed in the OGC “Best Practices
Document” [2]:
• Existing CityGML classes can be extended by additional attributes or relations
(“ADE-attributes”). ADE-attributes substitute the CityGML generic attributes and
additionally support relations to geometry objects, CityGML or ADE feature classes,
and the usage of Enumerations or Codelists.
• In the ADE schema, new classes (“ADE-classes”) can be defined, which optionally
can be derived from existing CityGML classes using the generalisation concept. In
consequence, an ADE-class inherits all attributes and relations of the base class.
Due to the rich information model, its extensibility, and the rapidly increasing data
availability all over the world, the combination CityGML + ADEs is a suitable information
model for a common engineering data backbone for urban energy, environmental, and
mobility planning.
PRELIMINARY WORK
In the past few years, the University of Applied Sciences Stuttgart (HFT) and the Technische
Universität Munich (TUM) have developed new urban energy simulation platforms, SimStadt
(HFT) and Energy Atlas (TUM), based on the CityGML data model. While their input
requirements for the calculation of the building heating demands were going far beyond the
available data structure of CityGML, they developed in parallel two different drafts of Energy
Application Domain Extensions (ADE).
In order to exchange the models and compare the energy simulation results, HFT and TUM
started working together on the harmonization of the ADE models into a unique Energy ADE.
Since that, several international urban energy simulation developers and users have joined this
initiative. In May 2014, an international group of experts from 11 European organisations
from Germany, France, Italy and Switzerland met to plan together the development of a
common Energy ADE for the CityGML urban information model. They were representing six
urban energy simulation platform developments: CitySim [3], SimStadt [4], EnergieAtlas [5],
Modelica library AixLib [6], Sunshine platform [7] and the Curtis platform [8]. This
collaborative work led to a first release of the Energy ADE in February 2015, which this
paper introduces.
OBJECTIVES
The objective of this Energy ADE is to store and manage data required for the calculation of
the building energy flows and its main results in the CityGML-based virtual 3D city model.
The physical boundary of this new data model is the building envelope, including the systems
installed on it (e.g. solar panel, shading devices). Small-scale centralized energy systems may
also be modelled in this Energy ADE. However, urban centralized energy infrastructures, like
district heating system or gas network, are not in the scope of this development, since they are
already represented by the CityGML Utility Network ADE [9]. The Energy ADE allows for
interfacing with the utility networks through substation node objects.
Following the philosophy of CityGML, this Energy ADE aims to be flexible, in terms of
compatibility with different data qualities, levels of details and urban energy model
complexities (from monthly energy balance, to sub-hourly dynamic simulation of software
like CitySim or EnergyPlus). It aims to be integrated as far as possible within the existing
CityGML data model, avoiding the creation of a parallel data structure that would be tailor-
made for specific calculation methods. Moreover, this Energy ADE considers the existing
international building and energy data specifications, like the INSPIRE Directive of the
European Parliament, as well as the recent US Building Energy Data Exchange Specification
(BEDES), and integrates their relevant energy-related attributes.
An important issue is also to track and manage the diversity of data sources and data qualities,
which highly affects the reliability and precision of the energy calculation results. For this
purpose, a concept of metadata is currently under development within the Energy ADE
working group. As it seems to be a general concern for many present CityGML
developments, we foresee a coordinated work with other CityGML developers in this field.
A MODULAR STRUCTURE
The Energy ADE is presently structured in 3 modules and a core model:
• Construction and materials
• Building Occupancy
• Energy and Systems
This structure enables to potentially reuse and extend some of its modules in other domains
and applications, with data exchanges and interoperability opportunities. For instance, socio-
economic studies may make use of the Energy ADE module Occupancy, while the module
Constructions and Materials could also be applied for acoustics or statics.
Energy ADE core
The Core of the Energy ADE contains the thermal building objects required for the building
energy modelling. These thermal building objects are linked to CityGML building objects
through the CityGML abstract classes _AbstractBuilding, _BoundarySurface and _Opening.
Figure 2 UML diagram extract of Building Energy ADE core
This schema is designed to be compatible with the four Levels of Detail (LoD) of CityGML
while modelling faithfully the different thermal zones. A building may have one or more
ThermalZone objects, which can be linked to a CityGML geometric object (e.g. Building,
BuildingPart, and Room in the LoD4 case) or be pure semantic objects (e.g. storey for a
CityGML Building whose LoD is lower than 4). Similarly, the ThermalBoundarySurface
objects may correspond to a CityGML _BoundarySurface (e.g. roof, outer wall) or not (e.g. in
case of an attic floor bounding the thermal zone for a CityGML Building LoD2-3).
The _AbstractBuilding extension contains energy-related attributes relevant for the building
energy analysis, partly inspired by the INSPIRE data specification.
Construction and Materials
This Energy ADE module may be used and further extended for multi-field analysis (e.g.
statistics and acoustics). It contains the physical characterization of building construction
elements and can be flexibly associated with any CityGML _CityObject (in particular a
SurfaceComponent, a ThermalBoundarySurface or a whole Building).
This module is based on a hierarchical structure Construction, Layer, LayerComponent and
Materials, inspired by the gbXML format.
Flexibly designed, the data model is applicable for static energy balance purpose (which
required the building contruction’s U-Values and windows g-Values) as well as for more
complex transient heat simulation. For this latter, the data model provides the material thermal
characteristics of each construction layer. Thus, the level of detail of these parameters fits the
granularity of urban energy models and the data availability.
Building Occupancy
This Energy ADE module may also be used and further extended for multi-field analysis (e.g.
socio-economics, demographics and census data). It contains the characterization of the
building usage, including HVAC operation set points, ownership and occupancy information
as well as information about the owner and facilities. This module connects to all other
elements of the Energy ADE (_AbstractBuilding and ThermalZone) through the class
UsageZone, which defines a zone of a building with a usage type considered as homogeneous.
One or several UsageZone may be associated to a ThermalZone, giving the flexibility to
model mixed-use buildings with a mono-zone or multi-zone building model. UsageZone may
have one or several Occupancy and Facilities objects. The object Occupancy represents a
homogeneous group of occupants (the decision was made not to model single occupants for
privacy reasons).
Temporal variables, such as occupancy rate or operation schedules (for heating, cooling,
ventilation or any facilities), can be modelled with different levels of details, depending on the
modelling purpose and the data availability: ScheduleLoD0 corresponds to a constant average
value. ScheduleLoD1 distinguishes usage and idle values and set their daily switch time.
ScheduleLoD2 is a collection of typical daily schedules, while ScheduleLoD3 corresponds to
detailed time series.
Energy and systems
This Energy ADE module contains information concerning the energy forms (energy demand,
supply and sources) and the energy systems (conversion, distribution and storage systems).
An EnergyDemand, which may be associated to any CityObject (in particular Building,
ThermalZone, UsageZone, BuildingUnit etc.). This object represents the useful energy
required to satisfy a given end use type such as heating, cooling, domestic hot water etc..
Other energy forms are EnergySupply, representing the part of the energy produced by the
energy conversion systems, which is supplied to satisfy the energy demand, and
EnergySource, corresponding to the final energy consumed by an energy conversion system.
All energy form objects are characterized by an energyAmount. It corresponds to a regular or
irregular time series, containing variable properties such as acquisitionMethod (e.g.
simulation, metering) or interpolationType. Therefore, both simulation results and metering
data may be stored in the data model, for instance for a comparison purpose. Moreover,
different time steps (sub-hourly to yearly, regular or not) corresponding to different building
simulation methods and metering systems may be used.
The EnergyConversionSystem objects, which contains general parameters such as
nominalEfficiency or yearOfManufacture, are specified by energy conversion technologies
such as Boiler, SolarThermalSystem etc… These systems may have different operation modes
for the needs of the different end uses, e.g. a reversible heat pump may supply during a year
the space heating demand, the domestic hot water demand and the space cooling demand,
representing three operation modes with different efficiencies, control strategies and operation
time. The produced energy (power or thermal) is then supplied to the end users through
energy distribution and energy storage systems.
CONCLUSION AND PERSPECTIVES
With the common objective of improving data exchange and tools operability in the urban
energy modelling community, an international expert group of research institutes,
standardisation organisations and GIS companies has extended the open city model standard
CityGML with an Energy ADE. This new development is a long iterative process, which has
just delivered its first results with this first XML Schema release 0.5.0.
During the second semester 2015, a test phase will allow confronting the Energy ADE schema
with concrete real project and software integration issues. The numerous and diverse urban
energy modelling and simulation tools used and developed by the different partners of this
expert group will serve as test applications, in order to verify and optimize the Energy ADE
flexible design. The present release is freely accessible on the SIG3D website:
http://www.sig3d.org/citygml/2.0/energy/. New active participants are very welcome in this
continuing development and test process.
ACKNOWLEDGMENT
We would like to thank all members of the Energy ADE development group who contributes
voluntarily to the present development: University of Applied Sciences Stuttgart, Technische
Universität Munich, Karlsruhe Institute of Technology, European Institute for Energy
Research, RWTH Aachen University / E.ON Energy Research Center, HafenCityUniversität
Hamburg, M.O.S.S Computer Grafik Systeme, Centre Scientifique et Technique du Batiment,
Electricité de France, Sinergis and Ecole Polytechnique Fédérale de Lausanne. Thanks in
particular to the Special Interest Group 3D (SIG3D) who provides the group with its
infrastructure and an official framework to our work.
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A building clustering approach for urban energy simulations
Article
Within the context of amongst others urban energy planning and energy system design, urban and district energy simulations have gained interest to quantify the energy use of existing districts. To reduce calculation time and in absence of adequate detailed building level data, urban energy simulations often deploy reductive modelling approaches based on a limited set of buildings, or archetype buildings. This may lead to significant modelling errors when the archetype buildings are not tailored to the studied location. This paper explores a building clustering approach that harvests available local building information, e.g. geospatial data, to generate a tailored set of archetype buildings. Focussed on simulating the annual heat demand or peak heat demand, this paper evaluates if clustering on building properties can be an alternative to clustering on the energy key performance indicators of interest to define the tailored archetypes. As consumption data on a building level is often not available, such an approach would eliminate the need to simulate the energy use for all buildings. The results show that indeed clustering on the properties is a viable alternative with robust results for both annual energy use and peak energy demand and a comparable accuracy compared to clustering on the targeted performance indicators.
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Ten questions on urban building energy modeling
Article
Buildings in cities consume up to 70% of all primary energy. To achieve cities’ energy and climate goals, it is necessary to reduce energy use and associated greenhouse gas emissions in buildings through energy conservation and efficiency improvements. Computational tools empowered with rich urban datasets can model performance of buildings at the urban scale to provide quantitative insights for stakeholders and inform their decision making on urban energy planning, as well as building energy retrofits at scale, to achieve efficiency, sustainability, and resilience of urban buildings. Designing and operating urban buildings as a group (from a city block to a district to an entire city) rather than as single individuals requires simulation and optimization to account for interactions among buildings and between buildings and their surrounding urban environment, and for district energy systems serving multiple buildings with diverse thermal loads across space and time. When hundreds or more buildings are involved in typical urban building energy modeling (UBEM) to estimate annual energy demand, evaluate design or retrofit options, and quantify impacts of extreme weather events or climate change, it is crucial to integrate urban datasets and UBEM tools in a seamless automatic workflow with cloud or high-performance computing for users including urban planners, designers and researchers. This paper presents ten questions that highlight significant UBEM research and applications. The proposed answers aim to stimulate discussion and provide insights into the current and future research on UBEM, and more importantly, to inspire new and important questions from young researchers in the field.
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3DCityDB - a 3D geodatabase solution for the management, analysis, and visualization of semantic 3D city models based on CityGML
Article
Full-text available
  • May 2018
Abstract Over the last decade, more and more cities and even countries worldwide are creating semantic 3D city models of their physical environment based on the international CityGML standard issued by the Open Geospatial Consortium (OGC). CityGML is an open data model and XML-based data exchange format describing the most relevant urban and landscape objects along with their spatial and non-spatial attributes, relations, and their complex hierarchical structures in five levels of detail. 3D city models, which are structured according to CityGML, are often used for various complex GIS simulation and analysis tasks, which go far beyond pure 3D visualization. Due to the large size and complexity of the sometimes country-wide 3D geospatial data, the GIS software vendors and service providers face many challenges when building 3D spatial data infrastructures for realizing the efficient storage, analysis, management, interaction, and visualization of the 3D city models based on the CityGML standard. Hence, there has been strong demand for an open and comprehensive software solution that can provide full support of the aforementioned functionalities. The ‘3D City Database’ (3DCityDB) is a free 3D geo-database solution for CityGML-based 3D city models. 3DCityDB has been developed as an Open Source and platform-independent software suite to facilitate the development and deployment of 3D city model applications. The 3DCityDB software package consists of a database schema for spatially enhanced relational database management systems (ORACLE Spatial or PostgreSQL/PostGIS) with a set of database procedures and software tools allowing to import, manage, analyze, visualize, and export virtual 3D city models according to the CityGML standard. Within this paper, the software suite is illustrated and explained in detail with respect to the related technical implementations and the underlying conceptual software design. Moreover, the utilization of 3DCityDB in different projects and practical application fields are also presented in this paper.
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SIMSTADT, a New Worflow-driven Urban Energy Simulation Platform for CityGML City Models
Conference Paper
Full-text available
  • Sep 2015
In this paper, we introduce new urban energy simulation platform SimStadt, which has been developed to support public authorities and engineering companies in the planning of the energy transition at urban scale. SimStadt design is marked by two particular features: 1-it is based on the open 3D city model CityGML and, 2-its workflow-driven structure is highly modular and extensible. These particularities allow him for a potentially unlimited variety of urban analysis, benefiting from the big geo data possibilities. This first version contains the workflows Solar and PV potential analysis, Energy demand and CO2 emission calculation, and refurbishment scenarios generation and simulation. Other workflows and plug-ins are under way, in particular district network design and simulation. This paper details these features and workflows, and presents an application on the administrative district of Ludwigsburg, a case study of half a million inhabitants spread over 34 municipalities.
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City-wide total energy demand estimation of buildings using semantic 3D city models and statistical data
Article
Full-text available
  • Sep 2013
The present climate and environmental policy efforts require comprehensive planning regarding the modification of the energy supply and infrastructures in cities. The strategic planning of the different measures requires a holistic approach and the combination of extensive and complex information. Within this paper, current developments in the context of the project Energy Atlas Berlin are presented. The Energy Atlas Berlin is based on the semantic information model of CityGML and provides an integrative data backbone for the common spatio-semantic representation of the city structure including energy related information of different themes. The virtual 3D city model of Berlin (mainly LOD2 building models) is used as data basis and has been enriched by information of different stakeholders and disciplines. In order to ensure the energy supply, the knowledge about the energy demands of buildings during the planning and optimization of measures is of great strategic importance. Therefore, this paper focuses on the city-wide estimation of the energy demands of buildings including heating, electricity and warm water energy in the city of Berlin using available official geobase and statistical data integrated within the Energy Atlas Berlin. It is explained in detail how the spatial and semantic properties of the 3D building models are being used to estimate these energy demands on an individual building level for the entire city.
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Modeling an application domain extension of CityGML in UML
Article
Full-text available
  • Dec 2012
This paper presents key aspects of the development of a Dutch 3D standard IMGeo as a CityGML ADE. The new ADE is modeled using UML class diagrams. However the OGC CityGML specification does not provide clear rules on modeling an ADE in UML. This paper describes how the extension was built, which provides general insight how CityGML can be extended for a specific applications starting from the UML diagrams. Several alternatives for modeling ADEs in UML have been investigated and compared. The best suited for the 3D standard option is selected and applied. Open issues and challenges are discussed in the conclusions.
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Simulation-Based Total Energy Demand Estimation of Buildings using Semantic 3D City Models
Article
  • Apr 2014
The present climate and environmental policy efforts require comprehensive planning regarding the modification of the energy supply and infrastructures in cities. The strategic planning of the different measures requires a holistic approach and the combination of extensive and complex information. Within this paper, current developments in the context of the project Energy Atlas Berlin are presented. The Energy Atlas Berlin is based on the semantic information model of CityGML and provides an integrative data backbone for the common spatio-semantic representation of the city structure including energy related information of different themes. The virtual 3D city model of Berlin (mainly LOD2 building models) is used as data basis and has been enriched by information of different stakeholders and disciplines. In order to ensure the energy supply, the knowledge about the energy demands of buildings during the planning and optimization of measures is of great strategic importance. Therefore, this paper focuses on the city-wide estimation of the energy demands of buildings including heating, electricity and warm water energy in the city of Berlin using available official geobase and statistical data integrated within the Energy Atlas Berlin. It is explained in detail how the spatial and semantic properties of the 3D building models are being used to estimate these energy demands on an individual building level for the entire city.
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Low order thermal network models for dynamic simulations of buildings on city district scale
Article
Dynamic building models can be a valuable part of integral energy system models at city district or urban scale, if parameterization and computation times do not exceed a practical limit. Low order thermal network models are able to represent a thermal zone by thermal resistances and capacitances with low computational costs. Yet, the widely used first-order model of ISO 13790 is only validated for a monthly time step. Following a similar approach, the Guideline VDI 6007 proposes a second-order model explicitly for transient simulations. Thus, the aim of this paper is to show how a building model based on this guideline performs in dynamic building performance simulations, compare its results to those of the ISO 13790 model, and evaluate its suitability for city district simulation. To this end, we implemented both building models from Guideline VDI 6007 and ISO 13790 in Modelica. We verified the VDI-model by simulating 12 test cases given in the guideline. To compare both models we defined a test case which evaluates the influence of outdoor air temperature on indoor air conditions. The VDI-model was subsequently used to simulate the buildings of a research campus as a performance test on city district scale. We parameterized the campus using building archetypes depending on four basic values. In all tests, the VDI-model proved to be a suitable solution for city district applications. Even so, defining suitable boundary conditions is of high importance and uncertain parameters like the periodic depth of penetration are subject to further investigations.
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Open GIS city geography markup language (City GML) encoding standard
Article
  • Jan 2008
Download the specification from https://www.opengeospatial.org/standards/citygml
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Integrated 3D Modeling of Multi-utility Networks and Their Interdependencies for Critical Infrastructure Analysis
Chapter
In today’s technologically advanced society the dependency of every citizen and company on working infrastructures is extremely high. Failures of critical infrastructures, such as the Italian blackout in 2003 or the failure of power supply in wide parts of Europe in 2006, demonstrate the strong linkage of networks across borders. However, also infrastructures within the same geographic region but of different types have strong interdependencies and failures in one type of network can have cascading effects onto the other networks. In order to support risk analysis and planning of emergency response actions the modeling of critical infrastructures and their mutual dependencies in 3D space is required. Decision makers need a comprehensive view of the disaster situation to be able to estimate the consequences of their action. For this purpose, a comprehensive understanding and simulation of cascading or looping effects as well as the propagation of the disaster extend is needed. But neither the existing utility networks models nor the international standards for modeling cities or buildings map the mutual interrelationships between different infrastructures or between the city and its infrastructures. In this paper the requirements and a novel framework for the integrated 3D modeling of critical infrastructures within cities is presented. By giving a dual representation utility network components are modeled both according to their 3D topography and by a complementary graph structure embedded into 3D space.
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Computer Modelling for Sustainable Urban Design
  • Jan 2011
  • D Robinson
  • F Haldi
  • J H Kämpf
  • D Perez
Robinson, D., Haldi, F., Kämpf, J. H., Perez, D. 2011. Computer Modelling for Sustainable Urban Design, in Computer Modellling for Sustainable Urban Design, 2011.
De Amicis, R. 2014. Large-Scale Assessment and Visualization of the Energy Performance of Buildings with Ecomaps
  • Jan 2014
  • L Giovanni
  • S Pezzi
  • Di Staso
  • U Prandi
Giovanni, L., Pezzi, S., Di Staso, U., Prandi, F., De Amicis, R. 2014. Large-Scale Assessment and Visualization of the Energy Performance of Buildings with Ecomaps. In Proceedings of 3rd International Conference on Data Management Technologies and Applications (DATA 2014).
A software platform to help Singapore to build a more smart and sustainable city
  • May 2015
  • D Blin
  • F Casciani
  • P Imbert
  • B Mousseau
  • A Pasanisi
  • P Terrien
  • P Viejo
Blin D., Casciani F., Imbert P., Mousseau B., Pasanisi A., Terrien P., Viejo P. A software platform to help Singapore to build a more smart and sustainable city. Energy Science Technology Conference 2015, Karlsruhe, 21st May 2015.