People

Associate Professor Lan Ding

Convenor of High Performance Architecture Research Cluster
Architectural Studies, Architecture, Research Cluster Staff, Smart Cities

PhD (USYD), MSci, BArch, Affiliate RAIA

Room: 
2021
Building: 
Red Centre
Phone: 
+61 2 9385 5593
Bio: 

Lan Ding is an Associate Professor in the Faculty of Built Environment. She received her PhD at the University of Sydney's Faculty of Architecture, Design and Planning. Prior to joining the Faculty of Built Environment at UNSW, Lan held the position of Senior Research Scientist at CSIRO (2000-2011) and Senior Lecturer at the Sustainable Buildings Research Centre at the University of Wollongong (2011-September 2013).

Lan has over 16 years research experience in energy efficiency, sustainable buildings and cities, climate change adaptation and mitigation, decision-making models, intelligent buildings and cities, building information modelling (BIM), urban information modelling, multi-agent modelling, GIS, life cycle assessment, as well as the application of artificial intelligence to built and urban environments. 

Lan has won various awards for research innovation and leadership, including national and state awards from the Australian Institute of Building, the Fresh Innovators Award and the CSIRO Divisional Award for excellence in a successful project providing an invaluable information resource to help the land development industry create more sustainable neighbourhoods.

Lan is a Convenor of High Performance Architecture (HPA) Research Cluster in the Faculty of Built Environment, UNSW Node Leader at CRC for Low Carbon Living, and Co-Chair of SBE16 International High-Performance Built Environment Conference (SBE 16 Sydney | International High-Performance Built Environment Conference).

 

Research Activities: 

Research Projects 

EEDMN BASIX: Mapping the Decision-Making Processes to Identify Barriers and Drivers to Meet or Exceed the BASIX Requirements of New Builds, NSW Office of Environment and Heritage (OEH) and CRC for Low Carbon Living (Project Leader).

UHI-DS: Microclimate and Urban Heat Island Mitigation Decision-Support Tool, CRC for Low Carbon Living (Project Leader ).

Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwellings - Phase 2, CRC for Low Carbon Living (Project Leader).

Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwellings, CRC for Low Carbon Living (Project Leader).

Node of Excellence in High Performance Architecture, CRC for Low Carbon Living (UNSW Node Leader).

Sustainable Smart Cities, Built Environment Research (Project Leader)

Development of an Immersive 3D Virtual Environment to Support Team Collaboration of Students, Built Environment Learning and Teaching (Project Leader).

Closing the Loop on Evidence-Based Low Carbon of Non-Residential Buildings, CRC for Low Carbon Living (Project Leader during 2014 - 2015).

3D Collaborative Virtual Sustainable Buildings Research Centre, University of Wollongong (Project Leader).

Building Life Cycle Assessment Case Studies, University of Wollongong and Cement Concrete & Aggregates Australia (Research Leader).

Sustainability Advisor (AccuRate Based), CSIRO and Federal Government Department of the Environment, Water, Heritage and the Arts (Project Leader)

Agent-based Consumption Behaviour Modelling and Simulation to Support Climate Adapted Urban Development, CSIRO Climate Adaptation Flagship (Project Leader).

Planning the Sustainable Urban Renewable of East Lake - Integrated Sustainability Assessment Platform (ISAP), CSIRO Climate Adaptation Flagship and ACT Planning and Land Authority (ISAP Research Leader).

Planning the Sustainable Urban Renewable of East Lake - Scoping 3D Visualisation Interface, CSIRO Climate Adaptation Flagship and ACT Planning and Land Authority (Project Leader).

Agent-based Urban Metabolism and Sustainability Platform, CSIRO Climate Adaptation Flagship (Research Leader).

DesignCheck (BIM-Based), CSIRO, University of Sydney, Woods Bagot and Building Commissions VIC (Project Leader)

Sydney Opera House FM Exemplar Project, CSIRO, University of Sydney, Sydney Opera House, et al (Research Leader)

LCADesign Commercialisation Activities, CSIRO and CRC for Construction Innovation (Project Leader)

PIM: An open digital information standard for the exchange of precinct information supporting carbon management throughout the urban development lifecycle, CRC for Low Carbon Living (Co-Investigator).

Enhancing Resilience of Aged Care Systems to Climate Change: Retrofitting Buildings and Sociocultural Systems, University of Wollongong (Co-Investigator).

Your Development, CSIRO Climate Adaptation Flagship (Co-Investigator).

Managing Information Flows with Models and Virtual Environments, CSIRO and University of Sydney (Co-Investigator).

Life Cycle Modelling and Design Knowledge Development in 3D Virtual Environments, University of Sydney and CSIRO (Co-Investigator).

DesignWorld: A Tool for Team Collaboration in High Band Virtual Environemnts, University of Sydney, CSIRO, Woods Bagot and Arup (Co-Investigator).

Grants: 

 

Recent Grants:

EEDMN BASIX: Mapping the Decision-Making Processes to Identify Barriers and Drivers to Meet or Exceed the BASIX Requirements of New Builds, March 2018-February 2019.

Sponsor/Grant: NSW Office of Environment and Heritage (OEH) and CRC for Low Carbon Living

Value: $116,000

Role: Project Leader

Partner Organisations: UNSW, NSW Office of Environment and Heritage (OEH), CRC for Low Carbon Living

 

UHI-DS: Microclimate and Urban Heat Island Mitigation Decision-Support Tool, January 2017-December 2018.

Sponsor/Grant: CRC for Low Carbon Living

Value: $420,389

Role: Project Leader

Partner Organisations: UNSW, Swinburne University, City of Sydney, Greater Sydney Commission, NSW Office of Environment and Heritage, LandcomNSW Spatial Services, BlueScope Steel, AECOM, Stockland, Western Sydney Regional Organisation of Councils, Parramatta Council, Southern Sydney Regional Organisation of Councils, Waverley Council, Inner West Council, Campbelltown Council, Sydney Water, PSMA Australia

Project Outline

 

NSW Government Open Data Visualisation for Urban Island Mitigation, October 2018-May 2019.

Sponsor/Grant: CRC for Low Carbon Living

Value: $69,791

Role: Project Leader

Partner Organisations: UNSW, NSW Office of Environment and Heritage (OEH), CRC for Low Carbon Living

 

CPD - Managing Urban Heat, August 2018-March 2019.

Sponsor/Grant: CRC for Low Carbon Living

Value: $18,000

Role: Project Leader

Partner Organisations: UNSW, CRC for Low Carbon Living

 

Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwellings, July 2014-June 2017.

Sponsor/Grant: CRC for Low Carbon Living

Value: $519,388

Role: Project Leader

Partner Organisations: NSW Department of Planning and Infrastructure; Australian Government Department of Industry; NSW Office of Environment and Heritage; and Council of the City of Sydney.

Project webpage: http://www.lowcarbonlivingcrc.com.au/research/program-1-integrated-building-systems/rp1017-validating-and-improving-basix-energy

Project Interim Report:  http://www.lowcarbonlivingcrc.com.au/sites/all/files/publications_file_attachments/rp1017_crc_basix_project_interim_report_helvetica_final_0.pdf

 

Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwellings - Phase 2, July 2016-June 2018.

Sponsor/Grant: CRC for Low Carbon Living

Value: $131,653

Role: Project Leader

Partner Organisations: NSW Office of Environment and Heritage.

 

CRC LCL Node of Excellence in 'High Performance Architecture', July 2015-December 2018.

Sponsor/Grant: CRC for Low Carbon Living

Value: $500,000

Role: Project Leader

Partner Organisation: UNSW Australia

 

Sustainable Smart Cities, 2017

Lan Ding, Mat Santamouris, Deo Prasad, Kathryn Merrick, Hussein Abbass, Matt Garratt, Sreenatha Anavatti 

Sponsor/Grant: Built Environment Faculty Research Grant 

Value: $12,000

 

Development of an Immersive 3D Virtual Environment to Support Team Collaboration of Students, 2017

Lan Ding and Chris Pettit

Sponsor/Grant: 2016 Scholarship of Learning and Teaching (SoLT) Grant

Value: $3,000

 

SBE 16 Sydney | International High-Performance Built Environment Conference 2016

Lan Ding and Paul Osmond

Sponsor/Grant: UNSW Faculty of Built Environment Research Symposia/Exhibition Grant

Value: $5,000   

 

Items to Support Field Research in High Performance Architecture and Informatics at Building, Landscape/Site and Precinct Scale, 2015

Paul Osmond, Lan Ding and Anir Upadhyay

Sponsor/Grant: UNSW Major Research Equipment and Infrastructure Initiative (MREII)

Value: $109,842

 

PIM: An Open Digital Information Standard for the Exchange of Precinct Information Supporting Carbon Management throughout the Urban Development Lifecycle, July 2014-June 2015.

Sponsor/Grant: CRC for Low Carbon Living

Role: Co-investigator

Partner Organisations: University of Melbourne; Brookfield Multiplex; Renewal SA; AECOM; and Aurecon.

 

 

 

 

 

 

 

 

 

 

 

Awards: 

Sustainable consumption and climate adaptation: priority research area for PhD scholarship in CSIRO Climate Adaptation Flagship, 2009-2011.

CSIRO Divisional Awards 2008 Sustainable Ecosystems: For excellence in a successful project providing an invaluable information resource to help the land development industry create more sustainable neighbourhoods, 2008.

Sydney Opera House FM Exemplar Project (CRC for Construction Innovation). The Gold Award of Special Merit and Project of the Year for “Adopting BIM for Facilities Management: Solution for the Sydney Opera House” at ACEA. 2007.

Sydney Opera House FM Exemplar Project (CRC for Construction Innovation). The Facilities Management Australia and Rider Hunt Terotech Industry Achievement Award. 2007.

National and NSW state professional awards from the Australian Institute of Building. DesignCheck Project. 2006.

The Fresh Innovators Award. 2005.

Honorary associate at the Faculty of Architecture, Design and Planning, The University of Sydney, 2003-2005.

Teaching & Supervision: 

Building Information Modelling, Computational Sustainability, Urban Modelling

 

 

Engagement: 

In the Media

Membership

  • Affiliate Member, The Royal Australian Institute of Architects

 

Supervision Area: 

PhD Supervision

Energy Efficiency and Sustainability

Smart Cities and Buildings

Climate Adaptation and Mitigation

 

 

Supervising: 

PhD Supervision

Samaratunga, M. An Evidence-Based Modelling Approach to Sustainability Assessment of Buildings and Policy Decisions.

Marzban, S. Facade Optimisation in a Single-Sided Ventilated Residential Building Targeting Thermal Comfort and Energy Efficiency. 

Munsami, K. A Diagnostic Model for Thermal Performance Assessment of the Building Envelope.

He, B. Modelling Effects of Urban Ventilation on Urban Heat Island in Precinct Context.

Qi, J. A Decision-Making Framework to Support Urban Microclimate Mitigation by Local Governments. 

Craft, W. PhD research.

Baghchesaraei, A. PhD Topic to be announced.

Completion 

Craft, W. Towards 'Proactive' Retrofitting: Developing a Regenerative Framework for Building Retrofits. (Master by Research)

Xiao, P. Development of Collective Intelligence for Building Energy Efficiency. (PhD)

Publications:
Book Chapters

Afrooz A; Ding L; Pettit C, 2019, 'An immersive 3D virtual environment to support collaborative learning and teaching', in Lecture Notes in Geoinformation and Cartography, pp. 267-282, 10.1007/978-3-030-19424-6_15

Ding L; Craft W, 2019, 'Mitigating Urban Heat', in Precinct Design Assessment - A Guide to Smart Sustainable Low Carbon Urban Development, Low Carbon Living CRC, https://apo.org.au/sites/default/files/resource-files/2019/07/apo-nid247361-1375176.pdf

Craft W; Petersen H; Haddad S; Ding L; Santamouris M, 2019, 'Mitigating Urban Heat for the Green Square Town Centre Redevelopment', in Precinct Design Assessment - A Guide to Smart Sustainable Low Carbon Urban Development, https://apo.org.au/sites/default/files/resource-files/2019/07/apo-nid247361-1375176.pdf

Santamouris M; Ding L; Osmond P, 2019, 'Urban heat island mitigation', in Newton P; Prasad D; Sproul A; White S (ed.), Decarbonising the built environment: Charting the transition, edn. 1, Palgrave Macmillan, pp. 337-355, 10.1007/978-981-13-7940-6

Santamouris M; Ding L; Osmond P, 2019, 'Urban Heat Mitigation', in Decarbonising the Built Environment Charting the Transition, Springer

Ding L; Drogemuller RM; Akhurst P; Hough R; Bull S; Linning C, 2009, 'Towards sustainable facilities management', in Technology, Design and Process Innovation in the Built Environment, pp. 373-392, 10.4324/9780203928325

Drogemuller R; Ding L, 2006, 'Automated code checking and accessibility', in Constructing the Future: nD Modelling, pp. 126-141, 10.4324/9780203967461

Ding L; Drogemuller R; Rosenman M; Marchant D; Gero J, 2006, 'Automating code checking for building designs-DesignCheck', in Clients Driving Innovation: Moving Ideas into Practice

Kohlhaas A; Mitchell J, 2006, 'Modelling cities', in Constructing the Future: nD Modelling, pp. 372-392, 10.4324/9780203967461

Maher ML; Rosenman MA; Ding L; Smith GJ; Marchant D; Dong A, 2005, 'Supporting collaboration and multiple views of building models in virtual worlds', in Clients Driving Innovation: Mapping the Terrain

Ding L; Liew PS; Maher ML; Gero JS; Drogemuller R, 2003, 'Integrating CAD and 3D virtual worlds using agents and EDM', in Chiu ML; Tsou JY; Kvan T; Morozumi M; Jeng TS (ed.), DIGITAL DESIGN: RESEARCH AND PRACTICE, SPRINGER, NATL CHENG KUNG UNIV, TAINAN, TAIWAN, pp. 301-311, http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000183787600029&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=891bb5ab6ba270e68a29b250adbe88d1

Gero JS; Ding L, 1997, 'Exploring style emergence in architectural designs', in None

Journal articles

Qi J; Ding L; Lim S, 2020, 'Ontology-based knowledge representation of urban heat island mitigation strategies', Sustainable Cities and Society, vol. 52, 10.1016/j.scs.2019.101875

He BJ; Ding L; Prasad D, 2020, 'Outdoor thermal environment of an open space under sea breeze: A mobile experience in a coastal city of Sydney, Australia', Urban Climate, vol. 31, 10.1016/j.uclim.2019.100567

He BJ; Ding L; Prasad D, 2019, 'Enhancing urban ventilation performance through the development of precinct ventilation zones: A case study based on the Greater Sydney, Australia', Sustainable Cities and Society, vol. 47, 10.1016/j.scs.2019.101472

Marzban S; Ding L; Fiorito F, 2017, 'An Evolutionary Approach to Single-sided Ventilated Façade Design', Procedia Engineering, vol. 180, pp. 582-590, 10.1016/j.proeng.2017.04.217

Craft W; Ding L; Prasad D; Partridge L; Else D, 2017, 'Development of a Regenerative Design Model for Building Retrofits', Procedia Engineering, vol. 180, pp. 658-668, 10.1016/j.proeng.2017.04.225

Samaratunga M; Ding L; Bishop K; Prasad D; Yee KWK, 2017, 'Modelling and Analysis of Post-occupancy Behaviour in Residential Buildings to Inform BASIX Sustainability Assessments in NSW', Procedia Engineering, vol. 180, pp. 343-355, 10.1016/j.proeng.2017.04.193

Santamouris M; Ding L; Fiorito F; Oldfield P; Osmond P; Paolini R; Prasad D; Synnefa A, 2017, 'Passive and active cooling for the outdoor built environment – Analysis and assessment of the cooling potential of mitigation technologies using performance data from 220 large scale projects', Solar Energy, vol. 154, pp. 14-33, 10.1016/j.solener.2016.12.006

Upadhyay AK; Ding L; Yee KWK; Prasad D, 2017, 'Post-occupancy Energy Consumption of BASIX Affected Dwellings in the Sydney Metropolitan Area', Procedia Engineering, vol. 180, pp. 331-342, 10.1016/j.proeng.2017.04.192

Munsami K; Prasad D; Ding L, 2017, 'The Role of Post Occupation Evaluation in Achieving High Performance Buildings through Diagnostics', Procedia Engineering, vol. 180, pp. 356-364, 10.1016/j.proeng.2017.04.194

Santamouris M; Haddad S; Fiorito F; Osmond P; Ding L; Prasad D; Zhai X; Wang R, 2017, 'Urban heat island and overheating characteristics in Sydney, Australia. An analysis of multiyear measurements', Sustainability (Switzerland), vol. 9, 10.3390/su9050712

Marzban S; Ding L; Timchenko V; Irger M, 2016, 'Facade Optimisation in a Wind-Driven Ventilated Residential Building Targeting Thermal Comfort, IAQ and Energy Consumption', International Journal of Environmental Science and Development, vol. 7, pp. 379-384

Zhao W; Ding L; Cooper P; Perez P, 2014, 'Smart home electricity management in the context of local power resources and smart grid', Journal of Clean Energy Technologies, vol. 2, pp. 73-79

Lawrence TM; Watson RT; Boudreau MC; Johnsen K; Perry J; Ding L, 2012, 'A new paradigm for the design and management of building systems', Energy and Buildings, vol. 51, pp. 56-63, 10.1016/j.enbuild.2012.04.016

Rosenman MA; Smith G; Maher ML; Ding L; Marchant D, 2007, 'Multidisciplinary collaborative design in virtual environments', Automation in Construction, vol. 16, pp. 37-44, 10.1016/j.autcon.2005.10.007

Lou Maher M; Liew PS; Gu N; Ding L, 2005, 'An agent approach to supporting collaborative design in 3D virtual worlds', Automation in Construction, vol. 14, pp. 189-195, 10.1016/j.autcon.2004.07.008

Ding L; Gero JS, 2001, 'The emergence of the representation of style in design', Environment and Planning B: Planning and Design, vol. 28, pp. 707-731, 10.1068/b2730

Conference Papers

Craft WJ; Ding L; Prasad D, 2017, 'Development of Regenerative Design Principles for Building Retrofits', in WSBE17 Hong Kong - Conference Proceedings, Construction Industry Council and Hong Kong Green Building Council Limited, Hong Kong, pp. 716-721, presented at World Sustainable Built Environment Conference 2017 Hong Kong, Hong Kong, 05 - 07 June 2017, http://wsbe17hongkong.hk/download/WSBE17%20Hong%20Kong%20-%20Conference%20Proceedings.pdf

Xiao P; Ding L; Prasad D, 2014, 'Modelling Adaptive Building Energy Systems and Human Behaviour: An Agent-Based Modelling Approach', in Grand Renewable Energy 2014

Zhao W; Ding L; Cooper P; Perez P; Robinson DA, 2014, 'Smart home system: integration of energy facilities and environmental factors', in Proceedings of the 7th international conference EEDAL’13 energy efficiency in domestic appliances and lighting

Zhao W; Cooper P; Perez P; Ding L, 2013, 'Cost-Driven Residential Energy Management for Adaption of Smart Grid and Local Power Generation'

Lawrence TM; Watson RT; Boudreau M-C; Johnson K; Mohammadpour J; Ding L, 2013, 'Smart Buildings Systems for Adaptation to the Coming Smart Grid', in Proceedings Clima

Lawrence T; Watson RT; Perry J; Boudreau MC; Ding L, 2012, 'Facilities management and modelling: Applying energy informatics to buildings', in The Fifth International Conference on Energy Research & Development

Morris J; Ballesty S; Ding L; Drogemuller R; Mitchell J; Schevers H; Leifer D; Schwede D; Wu J; Henrikson J, 2006, 'An integrated collaborative approach for FM-sydney opera house FM exemplar', in Proceedings of the 1st World Congress on Engineering Asset Management, WCEAM 2006, pp. 1135-1144

Wu J; Leifer D; Ballesty S; Ding L, 2006, 'Benchmarking facilities management in performing arts centres: An organizational learning perspective.', in The 10th Pacific Association of Quantity Surveyors Congress

Rosenman MA; Smith G; Ding L; Marchant D; Maher ML, 2005, 'Multidisciplinary design in virtual worlds', in Computer Aided Architectural Design Futures 2005 - Proceedings of the 11th International CAAD Futures Conference, pp. 433-442

Ding L; Drogemuller R; Rosenman MA; Gero JS, 2004, 'Automated code checking'

Ding L; Gero JS, 1998, 'Emerging Chinese traditional architectural style using genetic engineering', in International Conference on Artificial Intelligence for Engineering, HUST Press, Wuhan, China, pp. 493-498

Gero JS; Ding L, 1997, 'Learning emergent style using an evolutionary approach'

Reports

Ding L; He B; Petersen H; Craft W; Qi J; Yang S; Santamouris M; Prasad D, 2019, Assessing the Impact of Solar Photovoltaics and Air Conditioning Waste Heat on Urban Heat Island Effects, The NSW Department of Planning, Industry and Environment

Ding L; He B; Craft W; Petersen H; Osmond P; Santamouris M; Prasad D; Bartesaghi Koc C; Derksema C; Midlam N, 2019, Cooling Sydney Strategy, City of Sydney Council, http://www.lowcarbonlivingcrc.com.au/resources/crc-publications/crclcl-project-reports/sp0012u3-cooling-sydney-strategy

Ding L; Petersen H; Craft W, 2019, Microclimate and Urban Heat Island Mitigation Decision-Support Tool, https://apo.org.au/sites/default/files/resource-files/2019/06/apo-nid246691-1371981.pdf

Ding L; Aminpour F; Craft W; Liu E; Yenneti K; Lim B; Samaratunga GK; Paolini R; Prasad D, 2019, Understanding Decision-Making Processes to Meet or Exceed BASIX requirements, The NSW Department of Planning, Industry and Environment

Ding L; Upadhyay A; Craft W; Yenneti K; Samaratunga GK; Munsami K; Prasad D, 2019, Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwelling, https://apo.org.au/sites/default/files/resource-files/2019/03/apo-nid230251-1351421.pdf

Prasad DK; Lan D; Yenneti K; William C; Fox J; Ding L; Fan H; Craft W; Sanchez A; Li X, 2018, Guidelines for Sustainable Cities and Communities in China, UNEP, Nairobi, Kenya, DTI/2207/PA, https://resourceefficientcities.org/wp-content/uploads/2019/01/Guidelines-for-Sustainable-Cities-and-Communities-in-China.pdf

Yenneti K; Santamouris M; Prasad D; Ding L, 2017, Cooling Cities - Strategies and Technologies to Mitigate Urban Heat, CRC for Low Carbon Living, http://www.lowcarbonlivingcrc.com.au/sites/all/files/event_file_attachments/discussion_paper_cooling_cities_final.pdf

Ding L; Upadhyay A; Craft W; Munsami K; Samaratunga M, 2015, Validating and Improving the BASIX Energy Assessment Tool for Low-Carbon Dwellings

Ding L; Henriksen J; Leifer D; Spink G; Frowd A, 2006, Sydney Opera House–FM Exemplar Project (Procurement)

Ding L; Drogemuller R; Schevers H, 2006, Sydney Opera House–FM Exemplar Project (Review and Analysis on Benchmarking)

Other

Ding L; Fiorito F; Osmond P, 2017, Editorial, 10.1016/j.proeng.2017.04.159

Madan S; Ding L; Drogemuller R; Mitchell J; Schevers H; Tonelli M; Clark S; Frowd A; Ballesty S; Ferrara N, 2007, FM as a business enabler, solutions for managing the built environment, Cooperative Research Centre for Construction

Theses / Dissertations

Ding L, 1999, An Evolutionary Model for Style Representation Emergence in Design, phdthesis

Conference Abstracts

He B; Ding L; Prasad D, 2019, 'Modelling the effect of urban ventilation on urban heat mitigation in precinct context', in EMS Annual Meeting Abstracts, EMS Annual Meeting 2019, Copenhagen, presented at EMS Annual Meeting 2019, Copenhagen, 09 September - 13 October 2019, https://meetingorganizer.copernicus.org/EMS2019/EMS2019-613.pdf

Edited Books

Ding L; Fiorito F; Osmond P, 2017, International High-Performance Built Environment Conference – A Sustainable Built Environment Conference 2016 Series (SBE16), iHBE 2016, Elsevier