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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Data Management of the Environmental Monitoring Network: UNECE ICP Vegetation Case</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>G. Ososkov</string-name>
          <email>ososkov@jinr.ru</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>M. Frontasyeva</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>A. Uzhinskiy</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>N. Kutovskiy</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>B. Rumyantsev</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>A. Nechaevsky</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>S. Mitsyn</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>K. Vergel</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Laboratory of Information Technologies</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Frank Laboratory of Neutron Physics</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Joint Institute for Nuclear Research</institution>
          ,
          <addr-line>Dubna, Moscow Region</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Proceedings of the XVIII International Conference «Data Analytics and Management in Data Intensive Domains» (DAMDID/RCDL'2016)</institution>
          ,
          <addr-line>Ershovo</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
      </contrib-group>
      <fpage>202</fpage>
      <lpage>207</lpage>
      <abstract>
        <p>A new data management cloud platform is presented. The platform is to be applied for global air pollution monitoring purposes to assess the pathway of pollutants in the atmosphere. For this purpose a set of interconnected services and tools will be developed and hosted in the JINR cloud.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>
        Air pollution has a significant negative impact on the
various components of ecosystems, human health, and
ultimately cause significant economic damage. That is
why air pollution is a main concern of the Doctrines of
the environmental safety all over the world. Increased
ratification of the Protocols of the Convention on
Longrange Transboundary Air Pollution (LRTAP) is
identified as a high priority in the new long-term strategy
of the Convention. Full implementation of air pollution
abatement policies is particularly desirable for countries
of Eastern Europe, the Caucasus and Central Asia
(EECCA) and South-Eastern Europe (SEE).
Atmospheric deposition study of heavy metals, nitrogen,
persistent organic compounds (POPs) and radionuclides
is based on the analysis of naturally growing mosses
through moss surveys carried out every 5 years [1]. Due
to intense activity of the Joint Institute for Nuclear
Research (JINR), as a coordinator of the moss surveys
since 2014, Azerbaijan, Belarus, Georgia, Kazakhstan,
Moldova, Turkey and Ukraine participated in the moss
survey for 2015/2016. Nowadays the UNECE ICP
Vegetation programme [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ] is realized in 36 countries of
Europe and Asia. Mosses are collected at thousands of
sites across Europe and their heavy metal (since 1990),
nitrogen (since 2005), POPs (pilot study in 2010) and
radionuclides (since 2015) concentrations are
determined. The goal of this study program is to identify
the main polluted areas, produce regional maps and
further develop the understanding of long-range
transboundary pollution [
        <xref ref-type="bibr" rid="ref2">3</xref>
        ].
      </p>
    </sec>
    <sec id="sec-2">
      <title>2 Experiment and data interpretation</title>
      <p>
        Sampling is carried out in compliance with the
internationally accepted guidelines [4]. Such analytical
techniques as AAS, AFS, CVAAS, CVAFS, ETAAS,
FAAS, GFAAS, ICP-ES, ICP-MS, as well an INAA are
used for elemental determination. A total of 13 elements
are reported to the Atlas (As, Cd, Cr, Cu, Fe, Hg, Ni, Pb,
V, Zn, Al, Sb, and N). Nowadays POPs (whichever
determined) and radionuclides (namely, 210Pb and
137Cs) are accepted for air pollution characterization.
The results are reported as number of sampling sites,
minimum, maximum and median concentrations in
mg/kg. The data interpretation is based on Multivariate
statistical analysis (factor analysis), description of
sampling sites (MossMet information package) and
distribution maps for each element produced using
ArcMAP, part of ArcGIS, an integrated geographical
information system (GIS) [5]. Examples of GIS maps are
presented in Fig. 1.
Figure 1 Examples of distribution maps [
        <xref ref-type="bibr" rid="ref2">3</xref>
        ]
      </p>
      <p>Analytical results and information on the sampling
sites (MossMet set) reported to JINR include confidential
acceptance of the data from individual contributors, the
storage of large data arrays, their initial multivariate
statistical possessing followed by applying GIS
technology, and the use of artificial neural networks for
predicting concentrations of chemical elements in
various environments.</p>
      <p>As an example of the importance of this study, the
tendency of average median metal concentrations in
moss (± one standard deviation) since 1990 to 2010 are
presented in Fig. 2.</p>
    </sec>
    <sec id="sec-3">
      <title>3 Motivation and aim</title>
      <p>As discussed above, the ICP Vegetation programme
is very important project, but it has a serious weakness
related to its weak adoption of modern informational
technologies. There are dozens of respondents in existing
monitoring network and their number is increasing, but
information on collecting and processing of samples is
carried out manually or with minimum automation. Data
mostly stored in xls files and aggregated manually by the
coordinator. Files from respondents are usually passed to
the coordinator by email or by ordinary mail. There are
no common standards in data transfer, storing and
processing software. Such situation does not meet the
modern standards for quality, effectiveness and speed of
research. Lack of a single web-platform that provides
comprehensive solution of biological monitoring and
forecasting tasks is a major problem for research.</p>
      <p>Therefore the aim of the project is to create a cloud
platform using modern analytical, statistical,
programmatic and organizational methods to provide the
scientific community with unified system of gathering,
storing, analyzing, processing, sharing and collective
usage of biological monitoring data.</p>
      <p>The platform elements are to facilitate IT-aspects of
all biological monitoring stages starting from a choice of
collection places and parameters of samples description
and finishing with generation of pollution maps of a
particular area or state-of-environment forecast in the
long term. Mechanisms and tools for association of
participants of heterogeneous networks of biological
monitoring are to be provided in the platform. That
enables verifying obtained results and optimizes
research. The open part of the platform can be used for
informing public authorities, local governments, legal
entities and individuals about state-of-environment
changes.</p>
      <p>
        One more important aspect of ecological researches
relates to various statistical methods applied to process
collected data. Modern approaches to explore air
pollutions provided by heavy metals, nitrogen, POPs and
radionuclides include as a mandatory part multivariable
statistical and intellectual data processing. Latest
tendencies in data processing include extension of a set
of georeferenced data that is integrated in data processing
of surveyed data. So it is not limited by geographical,
topographical or geological information, what is
traditional in such cases, but also includes, for example,
satellite imagery and their products, topographic
highprecision data derived from aerial photography, etc.
These new data classes, contrary to the traditional ones,
are characterized by a high resolution and dynamic
nature – for example, satellite images represents a
reflection of solar radiation, which depends on the time
of day, season, cloud cover, etc. This in turn greatly
increases the amount of data to be processed. The task of
integration of different types of data is tied to the problem
of the development of new models and algorithms – such
as neural networks [6], self-organizing maps [
        <xref ref-type="bibr" rid="ref3">7</xref>
        ], etc. –
during the study of dynamic properties of ecological
processes among other things.
      </p>
      <p>So, one more aim of our project is to develop modern
software tools for multivariable statistical and
intellectual data processing oriented on the
GIStechnology.</p>
    </sec>
    <sec id="sec-4">
      <title>4 ICP vegetation data and required resources</title>
      <p>The moss data are to be collected for about 50
countries in Europe, Asia and Central America. Each
country has more than 100 monitored points, and several
hundred parameters must be taken into account for each
of them. A bulky archive is needed to perform
comparative studies and to estimate dynamics of
explored air pollution processes. Keeping in mind the
intensive data exchange and non-relational and
poorstructured character of data we can assess the size of our
database on the level of terabytes.</p>
      <p>Thus it is necessary for scientists to manage large
amounts of data, and it leads to many non-trivial
problems in IT field. It seems natural that a solution
should be centralized and outsourced to a cloud.</p>
      <p>From a cloud point of view, the amount of data and
computing leads to data intensive processing.
5 Data management on the unified cloud
platform</p>
      <p>To optimize the whole procedure of data
management, it is proposed to build a unified platform
consisting of a set of interconnected services and tools to
be developed, deployed and hosted in the JINR cloud [6].
The JINR cloud currently has 400 CPU cores, 1000 TB
of RAM and about 30 ТB of total local disk space on
cloud worker nodes for virtual machines and containers
deployment. Hosting services in the cloud allows scaling
up and down cloud resources assign to the services
depending on theirs load. When some component will
require more resources cloud can provide it without
affecting other components. This increases the efficiency
of hardware utilization as well as the reliability and
availability of the service itself for the end-users. Such
auto-scaling behavior will be achieved by using the
OneFlow component of OpenNebula platform [6], which
the JINR cloud is based on.</p>
      <p>We define requirements for the platform and specify
its components. The general architecture of the platform
and technologies used are depicted in Fig. 3.</p>
      <p>We analyze data that comes from the contributors.
The data samples can have 10 to 40 metrics depending on
the collecting area. Most of the metrics are optional, so
traditional relation databases will be ineffective. We also
want to have a possibility to change structure of the data
sample object without hard code modification to easily
integrate new projects and experiments into the platform.
We have a positive experience with MongoDB
(opensource, document database designed for ease of
development and scaling [9]) at our previous projects
where more than 5 million data records from 200+
contributors are processed so it was decided to use the
data base to store sampling results.</p>
      <p>The portal back-end will be built on Nginx (an open
source reverse proxy web server for HTTP protocol [10])
and developed with PHP (widely-used open source
general-purpose scripting language that is especially
suited for web development). That should provide
necessary performance and scalability. Web-portal with
responsive design that adjusts to different screen sizes is
the main interface of the platform. The portal allows
multilevel access to the data and has advanced data
processing and reporting mechanisms. Currently basic
functionality of the portal has been implemented and
authorized users can manage their project/regions, import
data samples and generate regional maps. At top of Fig.
4 one can see the interface for project management where
contributor can add, delete, edit or copy the datasets. At
bottom of the figure the map with the indication of
pollution distributions and basic instruments to configure
the map are presented.</p>
      <p>We have tried QGIS (Open Source Geographic
Information System [11]) and OpenLayers (opensource
javascript library to load, display and render maps from
multiple sources) for regional and global maps
representation. But QGIS and its web plugin is too hard
to maintain and develop. Now we are using OpenLayers
[12] and some of its specific layers that allows to do basic
interpolation to create concentration maps.</p>
      <p>
        Another interface to the platform is RESTful service
[
        <xref ref-type="bibr" rid="ref5">13</xref>
        ] that we are going to provide to the mobile and
desktop application and also for third-party services that
can be interested in the environmental monitoring data.
      </p>
      <p>Data import and export mechanism will be available
for the platform, so users can process data online or
upload it and use their local processing application.
Intelligent multi-level statistical data processing is one of
the platform important parts. We have tried several
solutions but statistical and analytical packages are still
under discussion. A very promising direction is the use
of artificial neural network applications for predicting
concentrations of chemical elements in various
environments. We have done some research in this field
but do not yet have the finished solution.</p>
      <p>6 Prediction and GIS-oriented data
processing</p>
      <p>
        Prediction is an important step of data analysis of any
ecological survey. Application of prediction methods
enables mapping of estimate values. Maps in their turn
provide visualization of spatial variability of data and can
be used for visual analysis so that ecological hazards can
be identified [
        <xref ref-type="bibr" rid="ref6">14</xref>
        ].
      </p>
      <p>
        Kriging is a widely-used interpolation technique used
for prediction, e.g. concentration of heavy elements in
moss [
        <xref ref-type="bibr" rid="ref7">15</xref>
        ], soil contamination [6]. Recently more and
more research is made towards integration of different
data sources like aerial and satellite photography together
with incorporation of new methods like artificial neural
networks.
      </p>
      <p>Mathematically, given a discrete function  (  ,   )
(response variable defined by measurements over
Cartesian coordinates) on an irregular grid of a set of
points  = {(  ,   )}, an interpolation procedure finds
 ̃( ,  ) for  such that  ̃( ,  ) is prediction for  for
∀( ,  ) ∈ ℝ2. Integration of data is done in such a way
that helps an interpolation procedure, like artificial neural
network frameworks, to make a better predictor
(interpolator). Such an approach is based on a conjecture
that neural networks are capable to employ hidden
nonlinear correlations that exist and hidden in the data.</p>
      <p>Formally, if compared to “classic” interpolation
where predictor variables are limited by Cartesian
coordinates, in this case a set of predictors is to be
expanded with other predictor variables  1( ,  ),
 2( ,  ),…,   ( ,  ). These can be topographical
features, elevation, products of aerial photography and
satellite imagery and many more different surface
properties.</p>
      <p>,   ,  1(  ,   ),  2(  ,   ), … ,   (  ,   ) =
 (  ,   ) ∀(  ,   ) ∈  ,
build a predictor</p>
      <p>̃  ,  ,  1( ,  ),  2( ,  ), … ,   ( ,  )
and establish an equality
 ̃( ,  ) =  ̃( ,  ,  1( ,  ), 2( ,  ),…,  ( ,  )). While
extended form for  ̃( ,  ) seems more complicated, it
simply allows an interpolation method to fuse in possible
non-linear correlations and make “better” predictions,
while other formal parts of the method stay the same.</p>
      <p>
        A modification of kriging called cokriging has been
proposed [
        <xref ref-type="bibr" rid="ref8">16</xref>
        ]. It is oriented on using these secondary
variables, as aerial and satellite protography, but has
some problems with applying them to real-world data.
Kriging is oriented on data that is normally distributed.
While it is somewhat true for lags of spatial coordinates
that are utilized in semivariogram and covariance
function, it is not always true for secondary predictors   .
Also, it is problematic to construct a covariance function
as it may naturally be anisotropic and even
nonsymmetric. An artificial neural network, on the other
hand, automatically adapts to nonlinearities and
nonnormally distributed variables.
      </p>
      <p>This approach also constitutes some problems which
are inherent to artificial neural networks. As each
concrete neural network is a product of a learning
procedure, some form of predictor evaluation has to be
incorporated. Usually, several different learning
procedures and network topologies are evaluated and
results of interpolation procedure are analyzed for
deficiencies like overfitting. Such superprocedure
effectively increases computational costs and may be
sped up with parallel computing. Other problems are
caused by data specifics, so some approaches of
regularization should be employed, like learning with
Gaussian noise.</p>
      <p>
        Different types of satellite imagery are currently
employed in data processing, like LandSat [
        <xref ref-type="bibr" rid="ref9">17</xref>
        ] and
MODIS (the Moderate-resolution imaging
spectroradiometer [
        <xref ref-type="bibr" rid="ref10">18</xref>
        ]). The latter project incorporates
two satellites with spectroradiometers (hence the name)
that is able to take satellite imagery with high spectral
resolution of 36 spectral bands. Whilst, if compared to
LandSat, it has moderate resolution (hence the name), it
allows deeper and more thorough analyses of Earth
surface, thus enabling interesting possibilities for
research towards correlation and causality (e.g.
contamination spreading catalysts and accelerants).
      </p>
      <p>Using raw spectral radiation bands of spectral
imagery is confronted with obvious interfering factors
such as sun azimuth, time of day and season, surface
altitude and slope and other.</p>
      <p>Thus, in addition to the running standard statistical
procedures which calculated descriptive statistics and
factor analysis, neural network data processing is
considered to be used in the given project, together with
various MODIS products, as surface reflectance, land
surface temperature, land cover, vegetation indices, land
use, etc.</p>
    </sec>
    <sec id="sec-5">
      <title>7 Conclusion</title>
      <p>The study of migration and accumulation of highly
toxic pollutants, which include heavy metals, persistent
organic pollutants and radionuclides, the influence of
pollutants on the various components of the natural and
urban ecosystems is the key problem of modern
biogeochemistry and ecology. The aim of the given
project is to create cloud platform using modern
analytical, statistical, programmatic and organizational
methods to provide the scientific community with unified
system of collecting, analyzing and processing of
biological monitoring data.</p>
      <p>Parts of the project have already been implemented.
The rest is going to be implemented in the next two years.
[1] United Nations Economic Commission for Europe
International Cooperative Programme on Effects of
Air Pollution on Natural Vegetation and Crops
(http://icpvegetation.ceh.ac.uk/
[4] HEAVY METALS, NITROGEN AND POPs IN
EUROPEAN MOSSES: 2015 SURVEY
http://icpvegetation.ceh.ac.uk/publications/docume
nts/MossmonitoringMANUAL-2015-17.07.14.pdf
[6] J. Alijagić, 2013. Application of multivariate
statistical methods and artificial neural network for
separation natural background and influence of
mining and metallurgy activities on distribution of
chemical elements in the Stavnja valley (Bosnia and
Herzegovina) : PhD thesis. University of Nova
Gorica.
description,</p>
      <p>URL:
[9] MongoDB site and</p>
      <p>https://www.mongodb.com/
[10] Nginx for Windows</p>
      <p>http://nginx.org/ru/docs/windows.html
[11] QGIS description</p>
      <p>http://www.qgis.org/en/site/
[12] OpenLayers description
http://docs.openlayers.org/
URL:
URL:
URL:
URL:</p>
    </sec>
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