Sajad Sayadi

The 8th ISPRS Geospatial Conference 2025 at the University of Tehran, Iran, December 16, 2025. A research poster titled "Detection and Attribution of Thermal Anomalies in Urban Blocks of Qom Using Time-Series Analysis of TIR Imagery". The visual content includes spatial distribution maps of 22 identified thermal anomalies and LST time-series graphs. The methodology highlights Median Absolute Deviation (MAD) for outlier removal and noise filtering and the Reed-Xiaoli (RX) algorithm for anomaly detection and identifying deviated thermal behaviors.

Stepping out of the forest for a day to apply my Remote Sensing expertise to the urban landscape!

Presented my poster on detecting thermal anomalies using Time-Series analysis at the 8th ISPRS Geospatial Conference 2025.

#RemoteSensing #ISPRS #TimeSeries #LST #ISPRSConference

🌐🌍🛰️🍁🌲🔥

19.12.2025 12:31 — 👍 15    🔁 1    💬 0    📌 0

An oak leaf floating on water

17.10.2025 21:01 — 👍 66    🔁 7    💬 3    📌 0

A very fascinating and detailed study on estimating Site Index using mobile laser scanning and deep learning, along with an excellent discussion on the challenges ahead. 🍁 🌳🔥 🌐

#ForestEcology
Thanks to @mariamoan.bsky.social and @hansoleorka.bsky.social and co-authors.
@skogrover.bsky.social

16.10.2025 17:01 — 👍 31    🔁 2    💬 0    📌 0

Comparison of Global Shutter (full sensor exposure) vs. Rolling Shutter (sequential line-by-line exposure).

#Photogrammetry #Imaging #Shutter #UAVphotogrammetry
#3DModeling #RemoteSensing #CameraTech

13.10.2025 02:44 — 👍 9    🔁 0    💬 0    📌 0

No matter what camera you use to capture images, you need to understand how rolling shutter and global shutter work and what sets them apart.

#Photogrammetry #Imaging #Shutter #UAVphotogrammetry
#3DModeling #RemoteSensing #CameraTech

13.10.2025 02:40 — 👍 22    🔁 2    💬 1    📌 1

Flowchart for moving beyond NDVI: Sentinel-2 multispectral data feeds two paths: (a) Generation of NDVI; (b) Calculate EVI coefficients with PSO → Classification with EVI. In parallel, Google Earth imagery → Manual classification (veg/non-veg).

Looking for something better than NDVI as a vegetation index?
Follow the flowchart below.

#RemoteSensing #Vegetationindex #NDVI #EVI #Sentinel2 #Workflow

See more details here👉 doi.org/10.1109/Metr...

27.09.2025 11:25 — 👍 11    🔁 0    💬 0    📌 1

Fantastic work and what a view! It's always great to see meteorological data collection in action. This is precisely the kind of valuable data that helps us understand, analyze, and act on weather conditions.

24.09.2025 20:58 — 👍 2    🔁 1    💬 0    📌 0

I'm glad you found the research interesting. I'd love to hear your thoughts, or the thoughts of others in this field. Do you have any experience with scene-specific tuning of EVI parameters?

24.09.2025 20:47 — 👍 1    🔁 0    💬 1    📌 0

Red: vegetation by tuned EVI but non-vegetation by traditional EVI; Blue: the opposite

We conducted a binary visual comparison of EVI vegetation maps (traditional vs optimized) over a semi-arid mountain site.

#RemoteSensing #EVI #SemiArid #VegetationIndex #Optimization #Binarymap

See more details here👇 doi.org/10.1109/Metr...

24.09.2025 18:22 — 👍 14    🔁 1    💬 0    📌 0

NDVI (left) vs PSO-tuned EVI (right) in semi-arid mountains; the optimized EVI produced a wider vegetation value range, higher variance, and mapped more vegetation pixels than NDVI and the conventional EVI.

‪Sajad Sayadi‬
Classic NDVI can be fuzzy over bright soils and sparse canopies. We re-parameterized EVI with PSO for semi-arid mountains on Sentinel-2.
Have you tried scene-specific EVI tuning?

#RemoteSensing #EVI #Vegetation #Indexes #PSO #Sentinel2

See more details here👇 doi.org/10.1109/Metr...

22.09.2025 16:54 — 👍 33    🔁 2    💬 0    📌 3