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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Techniques for Monitoring the Physical Activities and Predicting the Performance of the Students</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Shanthi Palaniappan</string-name>
          <email>shanthi.slm@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sridevi U.K</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Madhumitha Ramamurthy</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>Deep Learning</institution>
          ,
          <addr-line>Ensemble, LSTM, Physical Activity, RNN</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Karpagam College of Engineering</institution>
          ,
          <addr-line>Othakkal Mandapam, Coimbatore</addr-line>
          ,
          <country>India. Tamil Nādu</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>PSG College of Technology</institution>
          ,
          <addr-line>Peelamedu, Coimbatore</addr-line>
          ,
          <country>India. Tamil Nādu</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Sri Krishna College of Engineering and Technology</institution>
          ,
          <addr-line>Kuniamuthur, Coimbatore</addr-line>
          ,
          <country>India. Tamil Nādu</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>One of the essential competitive problems today is the primary healthy lifestyle. Selfactiveness is the most important part in leading a healthy life. Practicing and exercising regularly is the only way that will help us to improve our health. There is many positivity, like sinking the risk of chronic diseases and enhancing overall health and fitness. Doing regular exercises in our daily schedule makes our life healthy that overcomes health issues. This work monitors the simple physical actions of the students. The widely used UCI-HAR (Human Activity Recognition) dataset is used in this work for analysis. The major goal of this strategy is to track physical activities using the collected data by the gadget, which allows them to examine their performance. Long Short Term Memory (LSTM) along with Recurrent Neural Network (RNN) are used in this approach that ensembles to fit the model that achieves best result 93% accuracy. The activity of all the 30 volunteers, are trained and tested with the total train data of 7352, and test data of 2947 records. To test the dataset's accuracy, the ensemble technique is tested with 10 key attributes of their mean.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Physical</p>
    </sec>
    <sec id="sec-2">
      <title>1. Introduction</title>
      <p>2022 Copyright for this paper by its authors.</p>
      <p>
        Students' physical activities like lying, standing, running and walking is being monitored as
everyday activities and tracked as physical activities in HAR dataset. In this work, ensemble deep
learning method is used to trail the physical activity coaching among students and also to track the daily
actions. Huge applications like healthy ageing, medical screening are included in physical monitoring.
Research on medical field proves that there are more advantages on undergoing physical activities. If
enough physical activities is not done on a daily basis, would result in inactive behaviour associated
from all origins [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. In addition to the increased long-term risk of premature death, insufficient physical
exercise also has an impact on short-term quality of life, work ability, and social involvement [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        The research study proves that school kids and teen-agers require physical exercise at their initial
phase of physical human changes [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Weekly activities on sports by teen-agers gets more benefits that
improves their mental as well as physical health [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Absence of physical exercise at the young age also
leads to mental problems during their physical development [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Recognition of physical activities is
accessible by products like wearable gadgets and smart phones. These gadgets contain a set of sensors,
such as accelerometers and gyroscopes, as well as GPS, which, according to [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], can give the basic data
required for activity detection, offering a full picture of the past. More technologies, patents and
research are carried out on monitoring physical activities [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7-9</xref>
        ]. In some cases, these provide
individualized personal training functionality [
        <xref ref-type="bibr" rid="ref10 ref11">10,11</xref>
        ]. Monitoring the physical activity is one of the
major issues established few decades ago [
        <xref ref-type="bibr" rid="ref12">12-14</xref>
        ]. Development of new gadgets helps to create new
applications in variety of industries, including healthcare, sports and defense. Recent surveys [15-17]
have looked into the most important past research in this field in depth. This is the case, the scikit-learn
library has been used to identify physical activity. The majority of contemporary research work, among
other things, relies on WEKA [
        <xref ref-type="bibr" rid="ref12">12, 18-20</xref>
        ], ATLAB[21], or patentable developments, such as the work
presented by [22]. Scikit-learn package has many algorithms peer-reviewed by professionals and it’s
frequently utilised and grown popular nowadays.
      </p>
      <p>
        In this work, Scikit-learn package is used with Ageing Population Physical Activity Monitoring
PAMAP2 [23] dataset for monitoring that can be easily replicated. Recent study predicts that deep
learning approaches are used to classify and extract features with the dataset [24-30]. In this study, the
results obtained with deep learning approaches are exceeded by those obtained with other classifiers,
indicating that multiple analysis and evaluation is required. The reason behind using deep learning
techniques is to compare with existing classification algorithms working with signals that have already
been translated in to frequency domain [30]. Finally, when working with sensors incorporated in
battery-operated systems, one key study topic is to maximise the usage of energy [
        <xref ref-type="bibr" rid="ref13 ref14">31-34</xref>
        ].
      </p>
      <p>
        Wearable sensors for monitoring the activities is related to precision and battery consumption.
Collect and transfer all data gathered from all accessible sensors via the data network. Last but not least,
when dealing with sensors incorporated in battery-operated devices, one essential study topic is how to
maximise their energy consumption [
        <xref ref-type="bibr" rid="ref13 ref14">31-34</xref>
        ]. The UCI-HAR dataset collects all the activity labels such
as sitting, normal walking, standing, walking upstairs and downstairs. In this database, 57, 85,091
records having 561 features, 7352 training data, and 2947 test data for 30 volunteers. The training and
testing dataset are used to train and fit the LSTM and RNN models, which ensemble the results
numerous times for the best accuracy.
      </p>
      <p>Neural network models are non-direct which have a high difference that makes the final model
difficult to make prediction. There are many models in neural networks that are combined using
ensemble learning to decrease the prediction variance and generalization error. Ensemble learning
strategies can be grouped based on variables such as training data, model, and how predictions are
integrated. The outcome of the neural network model achieves above 93 percent precision by using
ensembling LSTM and the RNN model with the main 10 features like tBodyGyro-Mean-X,
tBodyGyroMean-Y, tBodyGyro-Mean-Z, tBodyAccMag-Mean-X, tBodyAccMag-Mean-Y,
tBodyAccMagMean-Z, tGravityAccMag-Mean-X, tGravityAccMag-Mean-Y, tGravityAccMag-Mean-Z,
tBodyGyroJerkMag-Mean-X, tBodyGyroJerkMag-Mean-Y and tBodyGyroJerkMag-Mean-Z [22].</p>
    </sec>
    <sec id="sec-3">
      <title>2. Methodology 2.1.</title>
    </sec>
    <sec id="sec-4">
      <title>Ensemble Learners</title>
      <p>
        To achieve better results, these models incorporate the predictions of a large number of base
estimators built using a specific learning technique [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. The random forest technique is made up of
112 decision-making algorithms [
        <xref ref-type="bibr" rid="ref15">35</xref>
        ] with predictions that use feature subset that are selected randomly
[
        <xref ref-type="bibr" rid="ref16">36</xref>
        ]. Since the decision trees has many different weights, analysis becomes too complicated. It requires
complex parameter settings or domain knowledge to perform with high-dimensional data. The number
of random forest decision trees and the important features are the key parameters to be updated by using
these techniques. The decision trees are fixed as 30 with a limit of 10 by testing some values. Maximum
n features are used in these classifications [
        <xref ref-type="bibr" rid="ref29">49</xref>
        ] that are similar to the randomized random forest
algorithms for achieving better computational splits [
        <xref ref-type="bibr" rid="ref17">37</xref>
        ]. There are two divisions that an additional tree
divides nodes and builds trees using the all-learning samples.
      </p>
      <p>
        In this study, Adaptive boosting, couples all types of algorithms that helps to enhance the efficiency
[
        <xref ref-type="bibr" rid="ref18">38</xref>
        ]. Voting classifier algorithms like adaptive boosting and bagging algorithm produce better
outcomes on any datasets [
        <xref ref-type="bibr" rid="ref19">39</xref>
        ]. The adaptive boosting algorithm, is selected as the top classifier
algorithm [
        <xref ref-type="bibr" rid="ref20">40</xref>
        ]. This algorithm such as bagging and AdaBoost have been very successful in improving
outcomes for various different classifiers on both simulated and real-world datasets [
        <xref ref-type="bibr" rid="ref19">39</xref>
        ]. AdaBoost, in
particular, has been voted the top out-of-the-box classifier in the world [
        <xref ref-type="bibr" rid="ref20">40</xref>
        ]. The AdaBoost algorithms
are used and recommended for constant multilevel-class domains. AdaBoost was used to evaluate the
situation [
        <xref ref-type="bibr" rid="ref21">41</xref>
        ]. We used AdaBoost to assess random forest output and other randomization.
2.2.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Deep Learning</title>
      <p>
        Deep learning is one of the important techniques used in the area of neural networks [
        <xref ref-type="bibr" rid="ref22">42</xref>
        ]. This
technique is used by processing multiple layers to form non-linear transformations. With the help of
progressive learning, the outputs of each layer are grouped. RNN, convolutional deep neural networks,
Deep and Deep belief neural networks are used in layers processing. As a result of these strategies, the
data inputs will be mechanically built, offering an additional generic answer because the feature
generation approach will be completely done automatically. These techniques are applied to a variety
of fields like pc vision, tongue processing, and speech recognition and so on, with progressive results
on numerous tasks [
        <xref ref-type="bibr" rid="ref23 ref24 ref25">43–45</xref>
        ]. Deep learning techniques have been used in a few publications to recognize
activities; a representative set may be found in [26-31]. The TensorFlow framework are recently
introduced by Google (Mountain View, CA, USA) [
        <xref ref-type="bibr" rid="ref26">46</xref>
        ] are used in DNN. The essential need for
applying these strategies is to test 280 attributes into classification.
      </p>
      <p>Varieties of topologies are tested that revealed two things: (1) Only exact topology styles have a
significant impact on the produced results; and (2) Simple architectures are closer to the optimum results
than the complex architecture.
2.3.</p>
    </sec>
    <sec id="sec-6">
      <title>Parameter Setup</title>
      <sec id="sec-6-1">
        <title>Data</title>
      </sec>
      <sec id="sec-6-2">
        <title>Testing</title>
      </sec>
      <sec id="sec-6-3">
        <title>Data</title>
        <p>Total
2
1
0
9
8
6
6
5
2
8
7
2
8
6
2
7
6
9
689012
278256
967268
603026
264231
867257
554132
235620
789752
722732
275451
998183
772188
298452
1070640
790734
301257
1091991
A C T I V I T Y L A B E L S</p>
        <sec id="sec-6-3-1">
          <title>Training Data</title>
          <p>Testing Data
6
2
0
3
0
6
1
3
2
4
6
2
7
5
2
7
6
8
2
3
1
4
5
complex unit with Input gate (i), Output gate (o), Memory cell (c) and Forget gate (f). The LSTM
technique is also used to transfer the data within the gates that decides the number of new inputs and
also the memory to be maintained by the forgotten gate. Equations (1)-(6) gives the details about the
functioning of LSTM.</p>
          <p>= 
ℎ
 = 
 =   .   −1 +   .</p>
          <p>ℎ(  ).  
  =  ( 

  +   ℎℎ −1 +   ) ,

 =  (   1 +</p>
          <p>ℎℎ −1 +   )
  =  (  
  +   ℎℎ −1 +   )
ℎ( 

  +   ℎ 1 +   )
(1)
(2)
(3)
(4)
(5)
(6)</p>
          <p>To aggregate the predictions of k LSTM spanning from 1 to 3, we have used ensemble algorithm
predictive system involves the usage of an ensemble algorithm. An ensemble can be easily executed by
taking the average of individual predictions. As a result, the ensemble's prediction for Activity A and
instance t at Equation (7), for example,</p>
          <p>
            To compare the ensemble LSTM, the total error reduction are calculated based on the average
percentage reduction [
            <xref ref-type="bibr" rid="ref28">48</xref>
            ]. The
          </p>
          <p>are calculated using Mean Squared Error or Mean Absolute
Error. The error is formed from ith time series and jth ensemble method by 
_
error_reductionj, denoted as, jth ensemble prediction method is defined as follows in Equation (8):
 then, the
 100 ( = 1   )
(8)</p>
          <p>Therefore, next step after training on first data set (n train), is to test the models and then forecasting
the next observation is represented in Equation (9):
(7)
(9)
 ( ,


) =
 = 1

∑
 =1
) =

1

∑
Where 
(
 ,</p>
          <p>Activity Mean
tBodyAcc-mean()-X
tBodyAcc-mean()-Y
tBodyAcc-mean()-Z</p>
          <p>tBodyAcc-XYZ
tGravityAcc-mean-X
tGravityAcc-mean-Y
tGravityAcc-mean-Z
tBodyAccJerk-mean-X
tBodyAccJerk-mean-Y
tBodyAccJerk-mean-Z</p>
          <p>WALKING
0.287
-0.155
0.205
0.426
0.205
 ), indicates the AUC score of the modeli, at time period t at 128 element time that
results in best result using LSTM ensemble.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>3. Results</title>
      <p>After applying the ensemble LSTM models, the accuracy of the model could be visualized clearly.
the three-dimensional data are trained and tested to monitor the physical activity. Figure 2, shows the
graphical representation of these mean values of all the cumulative outputs of all the 30 volunteers. By
considered the result of these activities, one could able to monitor the students and analyse the
performance and actions of all individuals.
-0.155
0.278</p>
      <sec id="sec-7-1">
        <title>1 WALKING</title>
      </sec>
      <sec id="sec-7-2">
        <title>4 SITTING</title>
        <p>0.4
0.3</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>4. Conclusion</title>
      <p>In the present work, we train our deep learning algorithms on activity labels at all-time intervals.
The monitoring parameters, indicates the movements of all the students. The features selected are used
to check the accuracy based on the mean values of the data collected that indicates the essential
parameter to analyse the monitoring benefits of all the individuals. The ensemble learning model are
tested to find the best combination models. The multiple LSTM RNN are ensembled to fit the model.
The selected features improve the monitoring system, to analyse the physical activity. The study
indicates that the multiple ensembled model with LSTM RNN neural network improves the prediction
accuracy about 93%.</p>
    </sec>
    <sec id="sec-9">
      <title>5. Acknowledgements</title>
      <p>We would like to thank the reviewers for providing suggestions to improve our work. We would
also like to thank our parents and family for supporting us in all our future growth.</p>
    </sec>
    <sec id="sec-10">
      <title>6. References</title>
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</article>