Archive for the ‘Public Activities’ Category

“Wow!” – I said to myself after reading R Helps With Employee Churn post – “I can create interactive plots in R?!!! I have to try it out!”

 

I quickly came up with an idea of creating interactive plot for my simple model for assessment of the profitable ratio between the volume waste that could be illegally disposed and costs of illegal disposal [Ryabov Y. (2013) Rationale of mechanisms for the land protection from illegal dumping (an example from the St.-Petersburg and Leningrad region). Regional Researches. №1 (39), p. 49-56]. The conditions for profitable illegal dumping can be describes as follows:

 

Here: k – the probability of being fined for illegal disposal of waste;

P – maximum fine for illegal disposal of waste (illegal dumping);

V – volume of waste to be [illegally] disposed by the waste owner;

E – costs of illegal disposal of waste per unit;

T – official tax for waste disposal per unit.The conditions for the profitable landfilling can be described as follows:

Here: V1 – total volume of waste that is supposed to be disposed at illegal landfill;

Tc – tax for disposal of waste at illegal landfill per unit;

P1 – maximum fine for illegal landfilling;

E1 – expenditures of the illegal landfill owner for disposal of waste per unit.

Lets plot the graphs (with some random numbers (except for fines) for a nice looking representation) to have a clue how it looks like.

 

Note that there is a footnote (this post provides nice examples on how to do it) with the values used for plotting – it is important to have to have this kind of indication if we want to create a series of plots.

Now I will show you the result and then will provide the code and some tips.

Playing with the plot

Tips and Tricks

Before I will show you code I want to share my hardly earned knowledge about nuances of the manipulate library. There are several ways to get static plot like that using ggplot, but some of them will fail to be interactive with manipulate.

  1. All the data for the plot must be stored in one dataframe.
  2. All data for plots must be derived from the dataframe (avoid passing single variables to ggplot).
  3. Do not use geom_hline() for the horizontal line – generate values for this line and store them inside dataframe and draw as a regular graph.
  4. To create a footnote (to know exactly which parameters were used for the current graph) use arrangeGrob() function from the gridExtra library.
  5. Always use $ inside aes() settings to address columns of your dataframe if you want plots to be interactive

The Code

<pre class="brush: r; title: ; notranslate" title="">library(ggplot2)
library(grid)
library(gridExtra)
library(manipulate)
library(scales)
library(reshape2)

## Ta --- official tax for waste utilisation per tonne or cubic metre.
## k --- probability of getting fined for illegal dumping the waste owner (0

(more…)

Today I received a copy of proceedings of the conference I participated in. A peculiar moment is that my article about using Random Forest algorithm for the illegal dumping sites forecast is the very first article of my section (as well as of the whole book) and it was placed regardless of the alphabetical order of the family names of the authors (this order is correct for all other authors in all sections).

My presentation and speech were remarkable indeed – the director of my scientific-research centre later called it “the speech of guru” (actually, not a “guru”, there is just no suitable equivalent in English for the word used). Also the extended version of this article for one of the journals of the Russian Academy of Sciences received an extremely positive feedback from the reviewers. So I suppose the position of my article is truly some kind of respect for the research and presentation and not a random editorial mistake.

Now I should overcome procrastination and make a post (or most likely two) about this research of mine.

 

I fixed an issue of my utility for polygon width calculation in a given direction caused by redundant geometry created in certain circumstances.  ‘Fixed’ – somewhat a too strong claim for a nasty about 100 lines long workaround-function where I had to comment almost every line to trace what is going on (optimisation is left for the feature). Nevertheless full functionality of the utility is now available! Updated version is here.

Another note: check validity of your polygons geometries beforehand to obtain correct results.

I have created an “Azimuth-Width” utility recently. It is designed to compute (for now) maximum or minimum width of the given polygon(s) in the given direction. Corresponding QGIS plugin coming soon (or not too soon), so this utility may help these who are in need right now.

Prereqirements:

  1. You have to have QGIS installed on your machine.
  2. QGIS have to be in PYTHONPATH. See: http://qgis.org/pyqgis-cookbook/intro.html
  3. If you are non-Windows user ensure that command “QgsApplication.setPrefixPath( qgis_prefix, True)” in the utility file have  a valid path to QGIS installation. If not – modify “qgis_prefix” to set correct value. It is “/usr” now – must work in most of cases.

General usage:

Copy width.py to the directory with a shh-file containing polygons.

Using console navigate to the directory. In console type:

:~> python ./width.py [file to analyse] [field to store values] [azimuth (decimal degrees)] [mode ('min' or 'max')] [mode-2 ('abs', or 'rel')] [algorithm ('byStep' or 'byVertex' or 'Mix')] [step (real numver, CRS units; for 'byStep' and 'Mix' only)]

Example:~> python ./width.py poly.shp width 285.9 max abs byStep 1.3

Where:

  • ./width.py – name of this utility file.
  • [file to analyse] – a shp-file with polygons to analyse.
  • [field to store values] – if it does not exist it will be created.
  • [azimuth] – a direction for width calculation. Accepts decimal degrees from 0 to 360.
  • [mode] – type of width to calculate. Currently ‘min’ (returns minimum width value in given direction) and ‘max’ (returns maximum value in given direction) modes are available. Mode ‘min’ used with ‘byVertex’ algorithm will return minimum polygon width different then 0.0. This will be different (greatly most time) to ‘min’ mode and ‘byStep’ or ‘Mix’ algorithm.
  • [mode-2] – if polygon is not convex it may have several segments in given direction. If you want to take sum of the segments of the result – use ‘abs’, if you want only the longest (shortest) segment – use ‘rel’. Fixed: Note that currently ‘rel’ sometimes will provide incorrect results for non-convex polygons and for convex polygons with redundant vertices on its edges. This issue will be solved when the behaviour of the intersection() command will be changed or when I will implement a workaround for it.
  • [algorithm] – algorithm that will be used: ‘byStep’, ‘byVertex’ or ‘Mix’. “byStep” algorithm (improved version of the general idea that described here) will take provided value (shp-file CRS units) and swipe the polygons line with the given step along the bounding box. Precision depends on the step. Speed and precision depends on step – lower step mean more precise result but computation will take more time. “byVertex” (general idea described here) will intersect polygon with the line only in vertexes of the given polygon. For convex polygons this algorithm will be faster and more precise using ‘max’ mode then “byStep” algorithm. But this algorithm is not suitable for ‘min’ mode. “Mix” algorithm will use both “byVertex” and “byStep” algorithm so in some cases it will be most precise but will consume even more time than ‘byStep’.
  • [step] – step for “byStep” and “Mix” algorithm. Takes decimal values in shp-file CRS units. Lower step means more precision but more computation time.

Some advises:

  1. Use Equal Area projections.
  2. Make sure your polygons have correct geometry. Otherwise the calculations will be incorrect.
  3. ‘byStep’ algorithm should be faster when polygon have enormous number of vertices.
  4. If you have a large variety in polygons area e.g. a continent and an island to save computation time you may define big step (like 1000 m or so) to swipe through continent faster. It will save computation time and a width for the small island will be calculated even if step is grater then any side of island’s’ Bounding Box: step for the island in this case will be 1/100 of the shortest side of it’s Bounding Box.

Ok, it’s time to finish the story about land monitoring in Sverdlovskaya region. In this post I would like to demonstrate some of the most unpleasant types of the land use.

Lets begin with illegal dumping. This dump (note that there is the smoke from waste burning down) is located right next to the potato field (mmm… seems these  potato are tasty). The ground was intentionally excavated here for dumping waste. Obviously this dump is exploited by the agricultural firm – owner of this land, but who cares…

Panorama of freshly burnt illegal dump

The next stop is peat cutting. A huge biotops are destroyed for no good reason (I can’t agree that use of peat as an energy source is a good one). At the picture below you can see a peat cutting with the area of 1402 ha. There are dozen of them in the study area…

Peat Cutting (RapidEye, natural colours)

But the most ugly scars on the Earth surface are left from mining works. There is Asbestos town in Sverdlovskaya region. It was names after asbestos that is mined  there. The quarry has an area of 1470 ha and its depth is over 400 meters. Its slag-heaps covers another 2500 ha… The irony is that this quarry gives a job for this town and killing it. You see, if you wand to dig dipper you have to make quarry wider accordingly. Current depth is 450 m and in projects it is over 900 m, but the quarry is already next to the living buildings. So quarry is going to consume the town… By the way, the local cemetery was already consumed. Guess what happened to human remains? Well, it is Russia, so they were dumped into the nearest slug-heap.

Here is the panorama of the quarry. You may try to locate BelAZ trucks down there 😉

Asbestos quarry

Here is the part of the biggest slag-heap:

A slag-heap

That’s how it looks from space:

Asbestos town area (imagery – RapidEye, NIR-G-B pseudo-colour composition)

And in the end I will show you the very basic schema of disturbed land in the study area (no settlements or roads included). Terrifying isn’t it?

Basic schema of disturbed land

Open GIS! is a conference for users and developers of open-source GIS. It will take place on November 17-18, 2012 in Moscow, Russia. The really cool thing is that participation in this crowd-source conference is free of charge!!! Of course modest donations will be appreciated and a sponsorship as well, but it is not mandatory – we want this event to be available for everyone who are interested in open geospatial software and data. Download leaflet!

A call for papers will be opened in August but already now you may propose topics of your talk or master-class to the committee.

Please, spread the word!

P.S. If you are a rear person who interested in illegal dumping research (from geospatial point of view) – come to this conference to hear my talk on it!

There was a press conference on Tuesday the 19-th about illegal dumping in Leningrad region (Russia). I was asked to be the main speaker there and to present to the press my recent study on illegal dumping prevention. I’ve already had two presentations on this subject recently at the international scientific conference in St. Petersburg State University and at the round tablefor the discussion of the upcoming “Let’s do it. Russia” clean up event.Some video from the press conference:

The main conclusion that I made by investigating possible impacts on illegal dumping prevention (such as penalty increase, chance of being caught increase and waste disposal fare decrease) is that decrease of the waste disposal fare for population is the most efficient way. And I managed to find two other publications that came to the exact conclusion (for example, there is an evidence that 1% waste fare increase leads to 3% increase of illegal dumping cases).

By the way I was able to assess probability of being caught for illegal dumping in Russia. It is about 10-5 (you can die while playing soccer with such probability).

The only way to reduce waste fares is to use waste as a resource. That means that the only way to prevent illegal dumping is to create waste management system that would be able to complete the zero waste goal.

And here is an abstract from my article:

Mechanisms of the land protection were discussed in this article. An algorithm of decision making whether to dump illegally or not was explained. Formulas for determination of profitable ration of expenditures per unit and amount of illegally dumping waste are substantiated. Effect from different types of impacts that can be used for land protection from illegal dumping were discussed (such as fares change, penalties change, penalty application probability change). Decreasing of waste disposal fares was acknowledged as the most effective way for illegal dumping prevention, but it is possible only if «zero waste» concept is implemented.

There was a scientific seminar dedicated to environmental risks assessment in the scientific-research centre where I work. A speaker was awfully ignorant in subject unfortunately. As a person who is experienced in environmental risk assessment (see my posts about risks and a particular methodology) I was afraid that I will be the one to ask the speaker (quite an old man) some inconvenient question about formulas he used, but luckily he was ashamed by someone else.

During the discussion the question of monetary aspect of the risk and damage to environment was raised: whether it is possible to use money as the measure of risks that only applicable to environment itself. In other words: is it rational to use money when assessing possible damage to solely ecosystem (there are no money in ecosystem by itself), and how to perform such assessment?

What do YOU think? I wasn’t able to find an appropriate answer at that moment, but now I believe I have a point. My answer is YES, we can use money to assess risks and damage dealt to ecosystem only.

Firstly the assessment is made by humans and for humans. And humans understand monetised value more easily. The approach that I want to propose is about assessment of money that have to be spent to recover ecosystem to exact the same state it was prior to caused or possible damage. Just imagine how much money one have to spent for recreating and reintroduction of just one extinguished species (a tasmanian wolf for example). Here you are a monetised damage to environment.

Another approach I have in mind is about evaluation of risks via relative live value of species (which can be easily monetised too). Lets use this formula for evaluation of life of individual of a given species: V=(1/N)*P, where V – relative value, N – population of the given species (or given areal of species), P – total population of the human beings. We will have a relative value as 1 for humans and 1*(P/N) for a given species. For example for a tiger we will have its relative individual value about 1 076 900! Literally, if we have a choice whether to save 1 million people or a single tiger, the tiger must be saved – not a million of people!!!

And we can monetise this value by multiplication on the average value of the single human life (you can play a bit with numbers given here).

So the damage to ecosystem may be assessed via loss of number of individuals of species that live in a given ecosystem and we are able to easily evaluate a relative value of the individuals of the each species, and it can be easyly monetised.

It’s actually already two month old news, but my research “Developement of the Universal Methodology for Assessement of Environmental Risk Caused by Fires at Illegal Dumps” (download in RUSSIAN), that was made special for Fire Monitoring Challenge (by GIS-Lab, Microsoft, NEXTGIS, several universities and GIS/spatial data corporations), was  awarded the 2-nd pace. The prize consisted of the fancy diploma, Lenovo IdeaPad G560 (thanks to all the gods it became much less uglier when I’ve installed openSUSE at it and applied an OSM sticker 😉 ), a wireless mouse (my wife was happy to grab it) and a nice book on remote sensing for children.

Instead of abstract:

Developed methodology for assessment of the fire probability in dependence of spatial location and actual area of illegal dump. It is applicable for any part of the world. Software used: QGIS, R.

Spatial component of the probability of the fire at illegal dump in Leningrad region, Russia

I was lucky to present this research at two conferences and today I’ve received a printed “minor” publication of the article (it is beta-version of the paper available at the link above). So it is possible now to cite it as:

Yury V. Ryabov (2011) Razrabotka univercal’noy metodiki rascheta veroyatnosti vozniknovenia pozhara na nesankcionirovennoy svalke // Sbornik nauchnih trudov molodyh specialistov, prepodavateley i aspirantov po resultatam provedenia Tret’ego molodezрnogo ecologichescogo congressa “Severnaya palmira”, 21-22 noyabria 2011, Sankt-Peterburg. – SPb NICEB RAN – pp. 93-106.

To Do: develope formula for composition coefficient calculation; translation to English; major publication.

P.S. If you are interested in this research and do not speak Russian don’t hesitate to contact me and ask for general translation.

OrbView-3 high resolution imagery became available as a public domain recently. One can access it via USGS’s EarthExplorer.

GIS-Lab decided to make a shp-file catalogue for the available imagery to have quick access to the metadata and coverage. You can download it here.

OrbView-3 coverage

 

PS. I’m glad I was able to help a bit with that.