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Processing OSGB Oblique Photography Data in ArcGIS Pro: A Step-by-Step Guide

Recently, while testing OSGB data and related software, I explored using ArcGIS Pro for this purpose. After successful verification, this article documents the specific workflow.

Required Tools

  1. ArcGIS Pro 3.0/3.1 (Other versions & ArcMap untested)
  2. Sample oblique photography dataset

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Calculating Polygon Centroids: Principles and Implementation

In a previous article "Adding Centroid Coordinates in QGIS Using Field Calculator", we demonstrated adding centroid coordinates via QGIS. This article explains the mathematical principles behind centroid calculation for polygons.

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Exporting SHP Feature Coordinates to TXT in QGIS: Practical Methods

When working with large SHP boundary files, exporting coordinates of specific district boundaries to TXT is straightforward in QGIS. Here are three approaches:

Method 1: GeoJSON Export

  1. Open SHP file and select target feature

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Python GDAL Tutorial: Raster Data Processing Essentials

This article summarizes common Python GDAL code snippets for geospatial data processing. GDAL (Geospatial Data Abstraction Library) is a foundational library for handling raster and vector geospatial data, maintained by the Open Source Geospatial Foundation (OSGeo). Implemented in C/C++, it provides Python, Java, and other language bindings. When calling GDAL's API in Python, the underlying execution relies on compiled C/C++ binaries.

GDAL Official Site: https://gdal.org/
Python API Documentation: https://gdal.org/api/index.html#python-api

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Visualizing Network Paths with BestTrace: Mapping Your Connection to Maps

During a recent ArcGIS session, my team lead asked:
"Where are ESRI's servers located?"
"Probably in the US," I replied instinctively.
"That means signals from Wuhan travel quite a distance!"

This sparked my curiosity: Could we visualize this network path?

Introducing BestTrace

This tool enables rapid network path visualization. See sample output:

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Python Workflows for GIS Data Conversion: WKT, Shapefiles

During development of a grid management system, I initially planned to use PostgreSQL for storing grid WKT data (for direct SHP export and map service publishing). Due to incompatibility with backend framework requirements, I switched to MySQL. This necessitated converting MySQL-stored WKT to Shapefiles. The solution: Java scheduled tasks invoking Python scripts to automate conversion. Below are the code implementations.

1. WKT to Shapefile Conversion

Preview:

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Installing ArcGIS on Apple Silicon Mac: A Step-by-Step Guide

Many GIS students inadvertently purchase MacBook only to discover that ArcGIS and most domestic GIS software lack macOS versions. This article summarizes solutions for running ArcGIS on M1 Macs. Better approaches are welcome in the comments.

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Decoding the Color-Changing Leaflet Logo: CSS Filter Magic

Yesterday in a technical group, an interesting question arose: How does Leaflet's official website achieve its smooth leaf logo color transition? While initially assuming it was a GIF animation, closer inspection revealed a more elegant solution.

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Processing China's Air Quality Monitoring Data: From Hourly Measurements to Annual Analysis

Air quality monitoring typically generates hourly or daily data, while environmental remote sensing research often requires long-term data aggregation and comparison. This guide provides a programming-free method for researchers to efficiently consolidate and analyze such datasets.

Data Acquisition

Hourly air quality data (AQI, PM~2.5~, PM~10~, SO~2~, NO~2~, O~3~, CO) is available from Wang Xiaolei's authoritative platform:
https://quotsoft.net/air/

Dataset Coverage:

  • National monitoring stations (~1,600 sites, primarily urban)
  • Beijing municipal stations (35 sites across categories):

    • Urban environmental assessment (12)
    • Suburban environmental assessment (10)
    • Reference/regional sites (7)
    • Traffic pollution monitors (5)


National station distribution

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