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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Influence of Historical Meteorological Data Processing in a Mobile Application of Weather Prediction, based on Data Mining</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Herwin Alayn Huillcen Baca</string-name>
          <email>hhuillcen@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Flor de Luz Palomino Valdivia</string-name>
          <email>fdeluz3@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>School of Systems Engineering, National University José María Arguedas</institution>
          ,
          <addr-line>Andahuaylas</addr-line>
          ,
          <country country="PE">Peru</country>
        </aff>
      </contrib-group>
      <fpage>144</fpage>
      <lpage>150</lpage>
      <abstract>
        <p />
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>In the city of Andahuaylas Peru,
agricultural region, the conditions of the weather
and especially the temperature is decisive
for the success or failure of the agricultural
campaigns, on the other hand the
information of UV radiation conditions the
prevention of health and life in general, this
information is shown by free internet
services, but in a wrong way, because it
comes from a remote location of the city
of Andahuaylas and also does not provide
detailed predictions for proper decision
making, in this way the present
investigation had the purpose of evaluating the
influence of historical meteorological data
processing on the efficiency of a mobile
application of prediction of temperature
and UV radiation, which provides real,
updated and predicted information of the
weather of the city of Andahuaylas, for it
was used the historical and current data of
the meteorological station of the National
University José María Arguedas of
Andahuaylas, which were analyzed using data
mining to obtain efficient prediction
models and were subsequently implemented in
the mobile application. To measure the
efficiency of the prediction, we compared
the mean absolute errors of the models
used by the National Service of
Meteorology and Hydrology of Peru, of the cities of
Arequipa, Iquitos and Lima, with values of
1.24, 2.66 and 1.485 respectively and the
mean absolute error of the prediction
model of the mobile application with a value of
1.18, which verifies the efficiency of the
proposed model and is the expected result.
In our planet, the elements of the weather are
fundamental for the development of the life in
general, they are periodic natural phenomena and
depends on factors like the geographical location.
In the case of Peru, specifically in the city of
Andahuaylas, whose major source of economic
development is agriculture, the temperature
associated with UV radiation is vital and essential, the
temperature variations condition the success or
failure of a campaign Agricultural, and on the
other hand, the levels of UV radiation directly
affect the health of the villagers. In this way,
predictive and real-time information on temperature
and UV radiation is of great importance.</p>
      <p>Under this approach, a mobile application for
prediction the temperature and UV radiation was
implemented, using the historical meteorological
information of a station located in the city of
Andahuaylas, which, when processed using data
mining, generates prediction models that receive
input data the current weather information and
generates numerical prediction of temperature and
UV radiation. Subsequently, the degree of
approximation of the actual temperature and UV
radiation levels against the prediction was evaluated.</p>
      <p>This paper is a contribution as a generalization
of the proposed predicted model and as a real
source of information of the climate for the city of
Andahuaylas.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related works</title>
      <p>Weather prediction is an important application in
meteorology and has been one of the most
scientifically and technologically challenging problems
around the world in the last century, so many
related works have been realized with data mining
techniques and machine learning.</p>
      <p>
        Olaiya and Barnabas
        <xref ref-type="bibr" rid="ref2">(Folorunsho Olaiya,
2012)</xref>
        , propose the use of data mining techniques
in forecasting maximum temperature, rainfall,
evaporation and wind speed. This was carried out
using Artificial Neural Network and Decision Tree
algorithms and meteorological data collected
between 2000 and 2009 from the city of Ibadan,
Nigeria. A data model for the meteorological data
was developed and this was used to train the
classifier algorithms. The performances of these
algorithms were compared using standard
performance metrics, and the algorithm which gave the
best results used to generate classification rules
for the mean weather variables. A predictive
Neural Network model was also developed for the
weather prediction program and the results
compared with actual weather data for the predicted
periods. The results show that given enough case
data, Data Mining techniques can be used for
weather forecasting and climate change studies.
      </p>
      <p>
        Khan, Muqeem and Javed
        <xref ref-type="bibr" rid="ref9">(Sara khan, April
2016)</xref>
        , propose that data mining is a technique that
helps in extracting relevant and meaningful
information from the set of data. It can be further
described as knowledge discovery process that
can be applied on any set of data. Data mining
techniques when applied on relational databases
can be used to search certain trends or patterns.
This paper provides a survey of different data
mining techniques being used in weather
prediction or forecasting. It also reviews and compares
various techniques being used in a tabular format.
      </p>
      <p>
        Bartok, Habala, Bednar, Gazak and Hluchý
        <xref ref-type="bibr" rid="ref5">(Juraj Bartok, 2010)</xref>
        , present the methods and
technologies for integration of the input data,
distributed on different vendors’ servers. The
meteorological detection and prediction methods are
based on statistical and climatological methods
combined with knowledge discovery-data mining
of meteorological data (messages, weather radar
imagery, “raw” meteorological data from stations,
satellite imagery and results of common
meteorological prediction models).
3
3.1
      </p>
    </sec>
    <sec id="sec-3">
      <title>Methodological Approach</title>
    </sec>
    <sec id="sec-4">
      <title>Problem Approach</title>
      <p>In the city of Andahuaylas there is a problem with
temperature information, as free internet services
provide wrong information, usually between three
and five degrees less than the actual measurement,
this causes confusion and uncertainty among the
population.</p>
      <p>
        The cause is that the free internet services takes
as a source of data the meteorological information
of the airport of Andahuaylas, which is located
17.5 km from the city, with an altitude of 11706
feet or 3568 meters
        <xref ref-type="bibr" rid="ref1">(Corpac SA, 2015)</xref>
        , against
the altitude of the city of Andahuaylas of 2901
meters.
        <xref ref-type="bibr" rid="ref1 ref11 ref8">(Regional Government of Apurimac
DIRCETUR, 2015)</xref>
        , this difference of 667 meters
makes both places present different climates, in
addition to belonging to different natural regions.
      </p>
      <p>The city of Andahuaylas and its environs have
as main productive activity to the agriculture,
which depends almost entirely on the elements of
the weather, therefore it is important to have
meteorological information predictive of the present
day and later for an appropriate decision making,
the problem arises because the prediction
information is not correct. It is known that in southern
Peru, UV radiation has the highest rates in the
world, this problem directly affects the health of
Peruvians through diseases of skin cancer and eye
disease, the human exposure to UV radiation, in
the case of Andahuaylas the problem is greater,
because there is no source of information
regarding the UV indices, both current and predictive, so
that people adopt preventive measures during the
hours that they will be exposed to the sun.
3.2</p>
      <p>
        Research Method
The objective is to evaluate the influence of
historical meteorological data on the efficiency of a
mobile application prediction of temperature and
UV radiation, based on data mining, in such a way
that in case of obtaining a mean absolute error
(MAE)
        <xref ref-type="bibr" rid="ref7">( Pablo Cortes Achedad, 2010)</xref>
        acceptable
predictive models and research in general, for the
case of the temperature must have an average
absolute error lower than 2.0 and for the case of UV
radiation, less than 1.0.
      </p>
      <p>Finally we propose a generalization of this
approach, for the application of prediction models
with an optimum amount of data and an efficient
algorithm.
4</p>
    </sec>
    <sec id="sec-5">
      <title>Analysis of meteorological data</title>
      <p>
        In order to generate optimal models of prediction
of temperature and UV radiation, based on the
analysis of the behavior of classification
algorithms of the WEKA tool
        <xref ref-type="bibr" rid="ref12">(Waikato, 2010)</xref>
        , taking
as input, the meteorological data of the
meteorological station of the National University José
María Arguedas of Andahuaylas, whose records of
temperature, UV radiation, humidity, wind speed
and rain are intervals of 5 minutes. Specifically,
prediction model algorithms were chosen for
temperature prediction after 24 hours, temperature
prediction after 48 hours, prediction of UV
radiation after 24 hours and prediction of UV radiation
after 48 hours.
4.1
      </p>
    </sec>
    <sec id="sec-6">
      <title>Pre-processing of data</title>
      <p>The processed data are registered in a mySQL
database of the web server of the National
University José María Arguedas of Andahuaylas, these
data correspond to all elements of the climate
recorded every 5 minutes, for the research was used
data of 6 months of registration.
4.2</p>
    </sec>
    <sec id="sec-7">
      <title>Selection of variables or characteristics</title>
      <p>
        The variables or characteristics correspond to the
attributes taken into account in the generation of
input files, these variables are hour, minute,
temperature, absolute humidity, wind speed, rainfall
and UV radiation. The objective was to evaluate
which elements are correlated with temperature
and UV radiation. Figures 1 and 2 show
correlations of variables.
For the selection of candidate algorithms to
generate the prediction models, we used as reference
the investigations that were used as antecedents
        <xref ref-type="bibr" rid="ref4">(José M. Molina, 2010)</xref>
        ; however, they can not be
used in their entirety, since it depends very much
on the nature of the Attributes and class attributes,
so we have the following classification algorithms
for generating prediction models: reptree, m5p,
kstar, linear regression, additive regression,
bagging, decision table, conjunctive rule, simple
linear regression. In fact, the WEKA tool
        <xref ref-type="bibr" rid="ref12">(Waikato,
2010)</xref>
        does not allow the use of other available
classification algorithms. There are other
algorithms that were not taken into account by the
high mean absolute error (MAE) that results from
the data analysis.
4.4
      </p>
    </sec>
    <sec id="sec-8">
      <title>Extraction of knowledge</title>
      <p>The input files are 28 corresponding to each
prediction taking data of 60, 30, 15, 7, 3 and 2 days
prior to data collection, counting input files and
candidate classification algorithms, proceeded to
train the respective algorithms for each prediction
model, in such a way to be compared among them
by means of the absolute average error.</p>
      <p>Figure 4: Results of algorithm training for
temperature prediction models at 48 hours.
From Figure 3, it is observed that as the size of
historical meteorological data decreases, the mean
absolute error (MAE) of temperature predictions
to 24 hours is similar to the results of the training
of algorithms for prediction models of
Temperature to 48 hours, UV radiation to 24 hours and UV
radiation to 48 hours. For the evaluation of the
choice of the prediction algorithm, it can be seen
that in Figures 3, 4, 5 and 6, the algorithm that
obtains the minimum value of the mean absolute
error is the KSTAR algorithms, with a value of
0.0931 For models of prediction of temperature at
24 hours, of UV radiation at 24 hours and of UV
radiation at 48 hours yields values of 0.0847,
0.1343 and 0.1349 respectively, all of them
through the algorithm KSTAR. Finally we
conclude for the generation of prediction models
we used the KSTAR algorithm and the data
size are 2 days before the date and time of
prediction.
5.1</p>
    </sec>
    <sec id="sec-9">
      <title>Construction of Mobile Application.</title>
    </sec>
    <sec id="sec-10">
      <title>Mobile Application</title>
      <p>
        The mobile application was developed for
platforms Android
        <xref ref-type="bibr" rid="ref3">(Google, 2015)</xref>
        , works from
version 4.0 API Level 14, the development tool used
was Android Studio Beta 0.8.6. The choice of the
platform and the development tool obey the
nonfunctional requirement to provide free information
and easy access.
      </p>
      <p>
        Currently the mobile application is available for
download in the "Google Play" repository
        <xref ref-type="bibr" rid="ref3">(Google, 2015)</xref>
        , under INFORAD's name, it is
free and available since July 2015. Figure 7 shows
the main interface.
The INFORAD mobile application has the
following functional requirements:
• Show the temperature prediction for the
current day for each hour of the day.
• Show the temperature prediction for the
next day for each hour of the day.
• Show the prediction of UV radiation for the
current day for every 30 minutes of the day,
from 6:00 a.m. to 6:00 p.m.
• Show the prediction of UV radiation for the
next day for every 30 minutes of the day,
from 6:00 a.m. to 6:00 p.m.
•
      </p>
      <p>Display real-time information on
temperature and UV radiation levels, updated every
5 minutes.
• Show health recommendations according to</p>
      <p>UV radiation levels.</p>
      <p>The only non-functional requirement is that the
INFORAD mobile application must provide free
and easily accessible information. To satisfy these
requirements, several components are required to
work synchronously, Figure 8 shows the
component diagram.
5.5</p>
    </sec>
    <sec id="sec-11">
      <title>Generation of current and predicted information.</title>
      <p>The data mining process for knowledge extraction
is a process involving hardware resource
consumption and resource time, which can not be
loaded to a mobile device, for reasons of hardware
and processing limitations, then developed
programs that generate current and predicted weather
information, executed on the general purpose
server of the Universidad Nacional José María
Arguedas, the resulting information is uploaded to
subdomain of the university
(http://radiacionv.unajma.edu.pe), for later use by
the INFORAD mobile application. Figure 9 shows
the prediction interface through intuitive and
easyto-read graphs.
The meteorological station used in the present
investigation is the DAVIS INSTRUMENTS
CORPORATION1, model WIRELESS VANTAGE
PRO2, this equipment was acquired in September
of 2014 and installed in November of 2014.
5.4</p>
    </sec>
    <sec id="sec-12">
      <title>Database Server</title>
      <p>The disadvantage of the meteorological station is
the lack of database connection, so we used the
mySQL server of the university, whose platform is
Debian GNU / Linux2, version 7.0, however
another service was required to connect to the
weather station, Extracts data every 5 minutes and
registers them in the mySQL database, then the
WEEWX3 service is installed and configured,
which is free and meets the requirements.
1 http://www.davisnet.com/
2 http://www.debian.org/
3 http://www.weewx.com/</p>
      <p>According to figures 10 and 11, it is observed that
there are 706 installations per user, from July
2015 to July 2017, likewise has an average rating
of 3,778.</p>
    </sec>
    <sec id="sec-13">
      <title>Result Obtained</title>
    </sec>
    <sec id="sec-14">
      <title>Result of Errors Obtained</title>
      <p>
        To evaluate this efficacy, we used the mean
absolute error (MAE) of each prediction versus the
real value and then the mean of all predictions to
obtain the mean absolute error (MAE), which
refers to the efficacy of the prediction. However, it
is also important to calculate the mean absolute
percentage error (MAPE)
        <xref ref-type="bibr" rid="ref7">(Pablo Cortes Achedad,
2010)</xref>
        . Five consecutive days of evaluation of the
predictions were chosen, reaching the following
results:
      </p>
      <p>MAE
MAPE</p>
      <p>Temperature
Prediction
At 24 At 48
hours hours
1.18 1.45</p>
      <p>UV Radiation
Prediction
At 24 At 48
hours hours
0.98 0.87
9.32%</p>
    </sec>
    <sec id="sec-15">
      <title>Results of prediction effectiveness</title>
      <p>
        The type of numerical prediction addressed in the
present research corresponds to a regional model,
so to evaluate the effectiveness of the results of
the predictions, a comparison of the mean
absolute error (MAE) of the proposed model with
Other prediction models of the region, in this case
there are no predictive models for the city of
Andahuaylas, but there is information about the
effectiveness of the ETA model (Vergaray, GJ
(2010),
        <xref ref-type="bibr" rid="ref10">SENAMHI, 2013</xref>
        ) of the National Service
of Meteorology and Hydrology of Peru, for some
Cities of Peru, as follows:
      </p>
    </sec>
    <sec id="sec-16">
      <title>Model</title>
      <p>ETA / SENAMHI
ETA / SENAMHI
ETA / SENAMHI
KSTAR/INFORAD</p>
    </sec>
    <sec id="sec-17">
      <title>City</title>
      <p>Arequipa
Iquitos
Lima
Andahuaylas
The analysis and evaluation of historical
meteorological data, through data mining, have an optimal
influence on the efficiency of the mobile
application of prediction of temperature and UV
radiation, since smaller errors have been obtained than
the ETA model (Vergaray, GJ (2010) , Currently
used by the National Service of Meteorology and
Hydrology of Peru, for the case of temperature
prediction at 24 hours, the present investigation
has an average absolute error of 1.17 compared to
a value of 1.80 generated by the ETA model.</p>
      <p>The KSTAR classification algorithm is the
most suitable for the generation of prediction
models of temperature and UV radiation, for the
city of Andahuaylas.</p>
      <p>The optimum data size for general prediction
models of temperature and UV radiation for the
city of Andahuaylas is 2 days ago, as it is proven
that the prediction is more accurate when taking
near-occurrence data.</p>
      <p>The degree of certainty or approximation of
temperature predictions is better predicted for the
next day than for the subsequent day, because the
mean absolute percentage error (MAPE) is
11.46% and 12.0% respectively.</p>
      <p>The degree of certainty or approximation of
predictions of UV radiation is better predicted for
the next day than for the subsequent day, because
the mean absolute percentage error (MAPE) is
38.62% and 40.77% respectively.</p>
      <p>Predicting the temperature generates errors less
than predicting UV radiation, because the
temperature has more stable values with respect to UV
radiation.</p>
      <p>It is possible to implement prediction models
and later prediction applications for other
elements of the climate that are also important as
information, such as rainfall, humidity, atmospheric
pressure, wind speed and direction.</p>
      <p>It is known that the weather in general is
periodic, it has an annual repetition cycle, so it would
be interesting to analyze the historical
meteorological data of at least 2 years ago to generate
predictions for the whole following year, day by day,
even hour per hour.
8
09</p>
    </sec>
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