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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Data Mining and Visualization: Meteorological Parameters and Gas Concentration Use Case</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>© Yas A. Alsultanny</string-name>
          <email>alsultanny@hotmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Arabian Gulf University Manama</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kingdom of Bahrain</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Proceedings of the XIX International Conference “Data Analytics and Management in Data Intensive Domains” (DAMDID/RCDL'2017)</institution>
          ,
          <addr-line>Moscow</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
      </contrib-group>
      <fpage>350</fpage>
      <lpage>353</lpage>
      <abstract>
        <p>Knowledge extraction from big data is one of the important subjects now and in future. Mining in the big data needs many steps, which must be implemented very carefully. The final step in big data mining is visualizing the results or summarizing the results numerically. This paper aims to mining the big data recorded by environmental station. These stations are recording the concentrations of some gases and meteorological parameters. The 2D and 3D data visualization is used to evaluate the capability of visualization in determining the effect of meteorological parameters on some gases that caused pollution. The results showing the visualization is a very important tool, and visualization can be used in mining big data, by showing the concentrations of gases. The paper recommends using big data visualization periodically as an alarming tool for monitoring the levels of pollution gases concentration.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>Big Data Mining (BDM) and Data Visualization
(DV) are two important hot topics in the field of
knowledge discovery. The big data can be visualized and
analyzed to extract knowledge. The visual analytical
tools have steadily improved during the last years in
order to work with big data. The data collected from
different resources, such as the station for monitoring
pollution gases. These stations usually have an hourly
readings to measure concentrations of gases such as;
ozone O3, nitrogen dioxide NO2, sulfur dioxide SO2,
carbon monoxide CO, carbon dioxide CO2, particulate
matter (PM10 and PM2.5), moreover these stations have
hourly readings for meteorological parameters such as;
Temperature (Temp), Humidity (Hu), Wind Speed (WS),
Wind Direction (WD), and Air Pressure (AP).</p>
      <p>
        Big data is a term used to describe some of current
directions in information technology, as a concept that
take into consideration data analysis. The amount of data
in the world is huge, and it grows in an annual basis of
50% of its original size [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. It is important to note that
most of the big data is unstructured data, where it is not
organized and does not fit the usual databases [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Big
data can be used as a useful tool to enhance decision
making [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Data Mining is the technique to get useful knowledge
out of databases; data mining requires pre-processing
and analytic approach for finding the value. Data mining
requires many operations such as data integration, data
selection, and so on [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Visual analytic first defined by Tomas and Cook in
2005 [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] as; the science of analytical reasoning facility
by interactive visual interface. Murray in 2013 [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]
described Data Visualization as; “fortunately, we
humans are intensely visual creatures. Few of us can
detect patterns among rows of numbers, but even young
children can interpret bar charts, extracting meaning
from those numbers’ visual representations. Visualizing
data is the fastest way to communicate it to others”.
      </p>
      <p>Air pollution is important in our life; most of the
pollutants in the air are a result of emissions from cars,
trucks, buses, factories, refineries, and other sources. The
objective of this paper is to highlight the aspects of Big
Data miming to visualize air pollution concentrations
and it is relative to meteorological parameters.</p>
    </sec>
    <sec id="sec-2">
      <title>2 Literature Review</title>
      <p>
        Big data rises with the huge growth of data. It refers
to the storing, processing, and analyzing the vast
amounts of data. Big data brings new challenges to
visualization because of the speed, size and diversity of
data. One of the most common definitions of big data is
data that have volume, variety, and velocity [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7-9</xref>
        ]. The
term “Big Data” is surrounded by a lot of advertising,
where many software vendors claim to have the ability
to handle big data with their products [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Innovations
in hardware technology such as those in network
bandwidth, memory, and storage technology have
assisted the technology of Big Data. The new innovations
coupled with the latent need to analyze the massive
unstructured data that stimulated their development [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>
        Data Mining is the field of discovering novel and
potentially useful information from large amounts of
data [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Data mining defined as the use of analytical
tools to discover knowledge in a database. The analytical
tools may include machine learning, statistics, artificial
intelligence, and information visualization [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Data
mining categorized into seven categories as Fayyad et al.
in 1996 [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] stated. These categories are regression,
clustering, summarization, dependency modeling, link
analysis, and sequence analysis. Knowledge Discovery
in Databases (KDD) is the processing steps used to
extract useful information from large collections of data
[
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Data mining manly has two methods: classification
is assigns items in a collection to target categories or
classes, and clustering is a form of unstructured learning
method. Decision trees are types of classifications such
as: Reduced Error Pruning (REP) tree, K Nearest
Neighbors (KNN), the J48 based on C4.5 algorithm, and
M5P algorithm is an improvement of the Quinlan’s M5
algorithm [
        <xref ref-type="bibr" rid="ref16 ref17 ref18 ref19 ref20">16-20</xref>
        ].
      </p>
      <p>
        “To visualize” has two meanings. “To form a mental
image of something” refers to a cognitive, internal aspect
whereas “to make something visible to the eye” refers to
an external, perceptual role [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. Visualization is any
kind of technique to present information [
        <xref ref-type="bibr" rid="ref22 ref23">22-23</xref>
        ]. Data
visualization refers to any graphic representation that can
examine or communicate the data in any discipline [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ].
The 3D visualization is gradually becoming the main
trend in many fields including population gases and
meteorological parameters [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>3 Data Visualization</title>
      <p>This study proposes a visualization method to
represent graphically air pollution big data, to be an
efficient method for knowledge discovery. This visual
methodology is useful for people who are working in
field of air pollution to have an efficient readability and
accuracy of data analysis. Data visualization is the use of
computer for visual representations of data. It aims at
helping decision maker to detect effectively into big data.
Data visualization is an efficient and intuitively
accessible approach to identify patterns in large and
diverse data sets.</p>
      <p>Gases and metrological parameters visualizations can
have two goals: Explanatory and Exploratory. Gases and
metrological parameters data are usually recorded by
automatic stations at regular time intervals. Metrological
data is typically multivariate that often consists of many
dimensions. Air pollution is a major concern in any city
through the world. The visualization technique is used to
aid visual analysis of the air pollution problem, followed
by metrological data for knowledge discovery.</p>
      <p>There are many steps must be taken in order to
prepare data for visualization, these steps are shown in
Figure 1. The steps are: stations sensors adjustment, data
recording, data filtering, data preprocessing,
normalization, aggregation, and visualization.</p>
      <p>Stations Sensors Adjustment</p>
      <p>Data Recording</p>
      <p>Data Filtering
Data Preprocessing</p>
      <p>Normalization</p>
      <p>Aggregation</p>
      <p>Visualization</p>
    </sec>
    <sec id="sec-4">
      <title>4 Data Collection and Analysis</title>
      <p>The data available for this paper were collected from
Arabian Gulf countries from one station in state of
Kuwait; it was hourly time series data for eleven years,
after data filtering and preprocessing, the data for one
year 2015 was analyzed in this paper. The data
represented on an hourly averaged reading, where the
yearly readings for each gas or parameter must be 8,760
(24 hr*365 day), but the real readings after filtering and
processing are 8,630, with 130 (1.5%) missed reading.
The Rapidminer version 7.5 was used for processing and
visualization the data of this paper.</p>
      <p>Figure 2 shows the effect of temperature on the
concentration of the five gases (O3, NO2, CO, CO2, and
SO2) and PM10. The figure visualizes the data
distribution by using two-dimensional diagrams; the
temperature has an opposite effect on O3 and NO2. The
concentration of O3 increased directly during the hottest
hours, when the temperature was above 40ºC. While the
temperature had a reverse effect on NO2, the
concentration of this gas became lower during the hottest
hours, and its concentration was in its lightest levels,
when the temperature was less than 10Cº. The effect of
temperature on CO and CO2 is very limited and this is
clear from the figure, this indicates the temperature has
no effect on these two gases. The hottest hours have a
direct effect on SO2 and PM10, their concentrations
usually increased during summer and especially in the
hottest hours of a day.</p>
      <p>Figure 3 shows the effect of humidity on the five
gases and PM10. The humidity has a reverse effect on O3
and NO2, their concentrations are increased with lower
concentration of humidity, moreover the concentrations
of CO, CO2, and SO2 increased with lower percentage of
humidity. The PM10 concentration significantly reduced,
when the humidity percentage was higher than 70%.
These results are true, because the highest percentages of
humidity, reducing the five gases and PM10 disperse.</p>
      <p>Figure 4 shows the three dimensions scatter
diagrams to visualize the effect of both temperature and
humidity at the same time on the five gases and PM10.
The figure shows again most of the readings of O3 are
concentrated in the region of hottest temperature and low
percentage of humidity. The concentrations of NO2
increased at the lowest temperature and humidity. For
CO, CO2, SO2, and PM10 their readings are concentrated
in the region of hottest temperature and low percentage
of humidity.</p>
      <p>
        A decision tree is a predictive model [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]. It was
implemented in this paper to predicate PM10, which is
measured in part per million (ppm), by stating the effect
of temperature and wind speed. To implement the
decision tree the PM10, temperature, and humidity were
classified into: 0=0-50, 1=51-150, 2=151-400,
3=401700, 4=701-1000, 5=1001-1500, 6=1501-2500, 7=2501
and more. The temperature in centigram degree (Cº)
classified into: 0=0-6, 1=7-11, 2=12-16, 3=17-21,
4=2226, 5=27-35,6=36-46, 7=47 and more. The wind speed
meter per second (m/s) classified into: 0=0-2, 1=3-5,
2=6-8, 3=9-12, 4=13 and more. The decision rules of the
decision tree to predicate PM10, as an example by using
temperature and wind speed-readings are as follows.
CO2
O3
      </p>
      <p>CO2
SO2
NO2</p>
    </sec>
    <sec id="sec-5">
      <title>SSOO22</title>
      <p>NO2
SO2
•
•
•
•
•
•
•
PM10
CO</p>
      <p>•
PPMM1100</p>
      <p>•
CO
PM10
•
•
of pollutant gases and effect of meteorological
parameters, by using these types of visualization the
decision makers can take their decision in stopping or
reducing the working hours of the factories or refinery
stations that cause the major pollution.</p>
      <p>We recommend each factory of refinery, using the
same methods of visualizing the pollution gases to take
their decision to stop their factory of refinery station or
reducing the hours of working hours, when the
temperature rises to more that 45Cº.</p>
    </sec>
  </body>
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