Categories - Natural Resources
Sub Categories
- Ecotoxicology - 4 projects
- Air Quality - 36 projects
- Water Supply and Quality - 88 projects
- Soil and Land - 73 projects
Topics
soil-survey, digital-soil-mapping, pedometrics, wastewater, stormwater, air-quality-data, pedology, landscape-ecology, openair, climers, swmm5, nasis, swmm, airquality, air-pollution-levels, aqi, integrated-modelling, gef, covid-19, drought-indices, soil-mapping, s4ss, water-management, epanet, ncss, eda, groundwater-recharge, landscape-metrics, heatmap, brazil, soil-respiration, toxicology, stac-catalog, aquatic-science, stac-api, lake, satellite-image-time-series, planetary-computer, image-time-series, mixing, stratification, aguaclara, water-treatment, water-distribution, code-for-america, human-health-assessment, west-oakland, openoakland, publication, publication-code, soil-texture-classification, automated-river-analysis, field-campaigns, neutral-landscape-model, ogr, openfluid-framework, simulators, air-quality-api, air-quality-index, aqi-readings, waqi, landtrendr, citizenscience, opensensemap, advection, ensemble-prediction, rainfall-prediction, stochastic-processes, grass, emissions-model, awsm, bcgov-csnr, groundwater-data, classification-algorithm, hyperspectral-image-classification, open-surface-mining, surface-mining-activities, airbase, big-earth-data, eo-datacubes, nodemcu, spi, water-quality-data, gis-based, soil-erosion, surface-runoff, airmonitoring, aqs, datamart, environmental-data-retrieval, r03, rprogramming, usepa, spectral-unmixing, civic-apps-team, nhd, openaq, openaq-api, openaq-data, ncss-tech, iot-device, MODFLOW, imod, preprocess, read, sm, air-pollutants, air-quality-measurements, cetesb, rio-de-janeiro, sao-paulo, plantower, pm10, pms5003, pms5003st, suitability-analysis, aem, aquatic, estuaries, nutrients, phytoplankton, sediment, acquisition, extract-data, smap-data, soil-moisture-sensor, hydrological, water-security, san-francisco-bay, waterbalance, waterflux, deep-percolation, cropland, fields, pytorch-lightning, earth-sciences, pse, drought, drought-index, sgi, spei, groundwater-level, geomatics, k-means, landslides-detection, merging-algorithms, object-based-image-analysis, optical-satellite-imagery, rsgislib, bias, air-quality-monitor, airly, macos-menubar, poland, sensor-station, smog, bcgov, frequency-analysis, hydat, summary-statistics, gsflow, pygsflow, geotechnical-engineering, pygef, wepp, defra, spatio-temporal-modeling, terrain, water-monitoring, global-database, sapper, water-models, radiometric-temperatures, source-energy-balance, epanet-matlab-toolkit, seasonal-calendar, accumulation, aqhi, aqhi-canada, cesi, naps, intensity-analysis, land-use-and-land-cover-change, luc-maps, lulc, statistical-models, geomorphometry, goal programming, mathematical programming, model predictive control, multi-objective optimization, reservoir management, stochastic optimization, water resource management, frm4sm, in-situ, ismn, qa4sm, idaes-pse, watertap, sensor-community, meris, olci, food-security, soils-revealed, comptox, covid19, data-dictionary, naming-conventions, odm, sars-cov-2, cigarettes, canairio-firmware, firmware, kssl, soilweb, ensemble-methods, ensembles, global-sensitivity-analysis, non-intrusive, parameter-estimation, uncertainty-quantification, water-distribution-networks, land-change-analysis, ow, hydraulic-modelling, swmmanywhere, 1d-cnn, conference, hyperspectral-data, hbv, hbv-model, matilda, melt, spotpy, hydrographs, well-hydrograph, process-flow-diagram, abwasser, datenmanagement, gep, kanalfernsehen, kataster, kek, leitungskataster, qgep, sewerpipe, sia405, teksi, vsa-dss, vsa-kek, werkinformationen, 2019, conservation-international, land-degradation, ldn, natural-climate-solutions, unccd, algal-bloom,
Projects
Contributors
Vince Kaandorp [email protected]
OST Projects: 1
Categories: Hydrosphere, Natural Resources
Sub Categories: Freshwater and Hydrology, Water Supply
Topics:
MODFLOW, groundwater, imod
nielsmulderdeltares [email protected]
OST Projects: 1
Categories: Hydrosphere, Natural Resources
Sub Categories: Freshwater and Hydrology, Water Supply
Topics:
MODFLOW, groundwater, imod
Simon Buijs [email protected]
OST Projects: 1
Categories: Hydrosphere, Natural Resources
Sub Categories: Freshwater and Hydrology, Water Supply
Topics:
MODFLOW, groundwater, imod
Betsy Romero Verastegui [email protected]
OST Projects: 1
Categories: Hydrosphere, Natural Resources
Sub Categories: Freshwater and Hydrology, Water Supply
Topics:
MODFLOW, groundwater, imod
arao53 [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Austin Ladshaw [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Kinshuk Panda [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
high, lab, laboratory, national, nrel, renewable, slurm, training, idaes-pse, idaesplus and 1 more
luohezhiming [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Kinshuk Panda [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
high, lab, laboratory, national, nrel, renewable, slurm, training
TimBartholomew [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
Sam Helman [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
carson-tucker [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Xinhong Liu [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Zhuoran Zhang [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
idaes-pse, idaesplus, watertap
Andy Charbonneau [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
climate, land, land-surface-model
Gabriele Bozzola [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
climate, land, land-surface-model
emarkows [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
climate, land, land-surface-model
Edward Speer [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
climate, land, land-surface-model
Rachele Morino [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds
Kelly Innes [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds
John Lindsay [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology, arcgis, gis-data, las, geographical-information-system, manipulating-geospatial-data, spatial-analysis and 3 more
jfbourdon [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology
Devon SIgler [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
water
Dharhas Pothina [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology, earth-data, earth-science, environmental-simulation, geographic, spec-0, spec-1 and 2 more
Duncan Hornby [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology, arcgis
Andrew Gene Brown [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology, dbi, geopackage, kssl, lab, ncss, rstudio-server and 2 more
Jason [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
citizen-science, water-monitoring, water-quality
Dan K [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology
Fabrizio Guglielmino [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology
Yvan Le Bras [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology, bioinformatics, dna, genomics, ngs, sequencing, usegalaxy and 1 more
iwismer [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
geomorphology, geomorphometry, geoprocessing, hydrology
Rockets_cn [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
citizen-science, water-monitoring, water-quality
Jonathan Raviotta [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
citizen-science, water-monitoring, water-quality
Séamus O'Connor [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, tran, dds
Fieran Mason [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
sgreylyn [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
Ryan Barber [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, geocoding, geocoding-api, geocoding-objects, geocoding-requests, dds
Steve Westenbroek [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
deep-percolation, groundwater-recharge, soil-water-balance, usgs, swb
ayoubc [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
groundwater-recharge, hydrographs, soil-water-balance, well-hydrograph
Greg Lawrance [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
Michal Fojtik [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, k8s-staging, dds
luciddreamz [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
Balakrishnan [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
Martin Nagy [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
Garrett Hyde [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
ethan92429 [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
karannewatia [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
jupierce [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
ewolinetz [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
bcgov-csnr, groundwater-data, dds
HannahSi [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
Anthony Verghese [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
danparaska [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aem, aquatic, ecology, estuaries, lakes, nutrients, phytoplankton, quality, sediment, water
fawnwong [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
Swastik Chaki [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
Arianna Curillo [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
aguaclara, water-treatment
Lewis Fishgold [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds, semantic-segmentation, spacenet-challenges
Rocky Breslow [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds, earth-observation, geospatial-analytics, aircraft, aircraft-performance, latex, reverse-engineering and 8 more
Taylor Nation [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds, earth-observation, geospatial-analytics, semantic-segmentation, geospatial-processing, geotrellis, bicycling and 4 more
Claude M. Schrader [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
civic-apps-team, hydrology, stormwater, watersheds
Stephanie Pennington [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
carbon-cycle, earth-sciences, soil-respiration, data-standard, reporting-format, reporting-tool
csim063 [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
landscape-ecology, neutral-landscape-model
tcadkin-usgs [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
usgs, water-quality, water-quality-data
Andrew Yan [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
usgs, water-quality, water-quality-data, internet-of-water, tableau, usgs-waterdata-labs, uswds, water, acwi, nhdplus and 7 more
Oliver [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
usgs, water-quality, water-quality-data, toxicity
Patrick Eslick [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
groundwater, groundwater-level
Aline Libres [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators
Jean-Christophe Fabre [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators, openfluid, services, casks, homebrew and 2 more
Jean-Christophe Fabre [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators, openfluid, vscode, vscode-extension, casks and 3 more
Armel Thoni [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators, openfluid
Michael Rabotin [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators
Manuel Chataigner [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
environmental-engineering, gdal, ogr, openfluid-framework, qt5, simulators
Kai Zhang [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
environmental-engineering, process-flow-diagram, wastewater, poopylab-project, wastewater-treatment
sshu2017 [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
environmental-engineering, process-flow-diagram, wastewater
Milind Sharma [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi, dart, dart-lang, dart-library and 1 more
Sam [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
Kristina Mancini [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
ubongab [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
Ireoluwatomiwa [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi, stac
Corey [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
AliShahpurwala [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
Joe Chilcott [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
ShootGan [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
Noor Kowshik [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
Amitesh [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
air-quality, air-quality-api, air-quality-data, air-quality-index, aqi, aqi-readings, waqi
dbhart [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water, olem
Arpan Seth [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water
Santiago [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water, mathematical-programming, modeling-language, nonlinear-programming
Joerg Rings [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water
Carl Laird [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water
Oops404 [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water
bernardoct [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, water, global-sensitivity-analysis, morris, salib, sensitivity-analysis, sensitivity-analysis-library, sobol, uncertainty, uncertainty-quantification
Lew Rossman [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, stormwater, hydraulics, hydrology, swmm5
michelleannesimon [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
ord, stormwater, hydraulics, hydrology, swmm5
Charles Morton [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
earthengine, jsonnet, stac
ouellette [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
eo-data, eo-research
Sara Troutman [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
anomaly-detection, detect-outliers, outliers, robust-random-cut-forest, streaming-data
Pierre Dulac [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
cft-terraform, data-analytics, end-to-end, marketing
Jenny Knuth [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Soil and Land
Topics:
atmospheric-modelling, atmospheric-science, space-weather
rchlumsk [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Water Supply, Water Supply and Quality
Topics:
diagnostics, hydrology, water, water-resources, watershed
Mat Schaffer [email protected]
OST Projects: 1
Categories: Natural Resources
Sub Categories: Air Quality
Topics:
alerting, business-intelligence, cloud-management, infrastructure-as-code, distributed-tracing, telemetry, hash-extensions