The Advisory Boar

By Abhijit Menon-Sen <>

An introduction to using Landsat data with GRASS

This brief introduction to acquiring and processing Landsat imagery is based on the notes I took while creating PAN-sharpened, false-colour mosaics of the Landsat-7 image tiles that cover my city. This was my first foray into remote sensing, image processing, and GIS, and I could have used a guide like this one when starting out.

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Better time management through profiling

This page is about the most potent charm in my long-standing quest for better time management: a program to help me keep track of exactly where and how my time is spent.

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Books about Indian birds

I am often asked to recommend a field guide, usually by beginners, or people who have just started to get interested in serious bird-watching. There aren't many available; and since I've used all of them at one time or another, here are some notes about the ones I like best.

A Field Guide to the Birds of India

By Krys Kazmierczak, illustrated by Ber van Perlo.

Published in 2000 by Pica Press (UK).
Reprinted in 2006 by Om Book Service (India).

If you have to pick just one book, this is the one I recommend.

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Vinayak/Pangot/Sat Tal, February 2008

My friend Gaurav Rai and I went to Uttaranchal for five days last week with a new tent (mine), a new rucksack (his), and a new camera (mine). This is a slightly delayed report.

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Easy user authentication with HTTP

Many small CGI programs need little in the way of access control: anyone may read, but only certain users are allowed to write. Here's an unobtrusive way to implement this scheme.

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Palam Vihar: bird checklist

This is a list of bird species I have identified in Palam Vihar, wedged between the borders of Delhi and Haryana. It is no longer actively maintained.

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Confluence-Hunting in Uttaranchal, January 2005

In January 2005, inspired by, Gaurav Rai and I decided to look for three degree confluences North of Delhi:

  • 29N 79E (visited successfully)
  • 29N 80E (not attempted, but subsequently visited by someone else)
  • 30N 80E (visit abandoned due to snow)

These are my recollections of this long-overdue trip to the mountains. Rai has written his own account of our travels.

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A photo album with nice URLs

A CGI script I used at one time to manage my photo albums.

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Differences between the IOC and Clements bird checklists

This page is a summary of the changes between the International Ornithological Congress's "Birds of the World: Recommended English Names" (Gill, F., and Wright, M., 2006), and the recently-published sixth edition of "The Clements Checklist of Birds of the World" (Clements, J. F., 2007).

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mod_leech: Per-user download limits for Apache 1.3.x

mod_leech is an Apache 1.3.x module which uses a MySQL database to enforce per-user download and concurrent-login quotas.

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