Edge Computing
Edge Computing
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   Abstract—Improving efficiency of healthcare systems is         detection, heart failure, etc.). All these things will report
a top national interest worldwide. However, the need of           an impressive amount of data that need to be transported,
delivering scalable healthcare services to the patients while     swiftly processed, and stored, while ensuring privacy pro-
reducing costs is a challenging issue. Among the most
promising approaches for enabling smart healthcare (s-            tection. Given these requirements, the conventional cloud
health) are edge-computing capabilities and next-generation       computing paradigm becomes unsuitable for s-health, since
wireless networking technologies that can provide real-time       a centralized approach cannot provide a sufficiently high
and cost-effective patient remote monitoring. In this paper, we   level of scalability and responsiveness, and it will impose
present our vision of exploiting multi-access edge computing      while an exceedingly heavy traffic load to communication
(MEC) for s-health applications. We envision a MEC-based
architecture and discuss the benefits that it can bring to        networks. A new approach has therefore emerged, known
realize in-network and context-aware processing so that the       as Multi-access Edge Computing (MEC), defined as the
s-health requirements are met. We then present two main           ability to process and store data at the edge of the network,
functionalities that can be implemented leveraging such an        i.e., in the proximity of the data sources. The advantage
architecture to provide efficient data delivery, namely, mul-     of MEC in a smart heath environment is multifold as it
timodal data compression and edge-based feature extraction
for event detection. The former allows efficient and low dis-     can provide short response time, decreased energy con-
tortion compression, while the latter ensures high-reliability    sumption for battery operated devices, network bandwidth
and fast response in case of emergency applications. Finally,     saving, as well as secure transmission and data privacy [1].
we discuss the main challenges and opportunities that edge        Furthermore, it can be applied to various network scenar-
computing could provide and possible directions for future        ios, including cellular, WiFi and fixed access technologies.
research.
   Index Terms—Edge computing, smart health, Internet             This paper paves the way for MEC usage in smart heath
of Medical Things (IoMT), context-aware processing, deep          environment through answering the following questions:
learning.                                                            • What are the motivations and main expected benefits
                                                                        of leveraging the MEC architecture in s-health sys-
                     I. I NTRODUCTION
                                                                        tems?
   The evolution of computational intelligence and Internet          • What are the s-health requirements, solutions of
of Medical Things (IoMT), along with the advances of                    MEC, and open challenges?
next-generation wireless technologies, has boosted the               In what follows, Section II introduces a MEC-based
development of traditional healthcare processes into smart-       system architecture that meets the s-health requirements,
healthcare services. Smart-health (s-health) can be consid-       highlighting the benefits of pushing data processing and
ered as the context-aware evolution of mobile-health, lever-      storage toward the data sources. Section III presents
aging wireless communication technologies to provide              context-aware solutions for implementing multimodal data
healthcare stakeholders with innovative tools and solutions       compression, in-network processing, and event-detection at
that can revolutionize service provisioning. In particular, s-    the edge. Section IV then discusses some challenges that
health enables remote monitoring, where patients and care-        MEC poses and further opportunities that such a paradigm
givers leverage mobile technologies to provide information        offers. Finally, Section V concludes the paper.
about their health remotely – a service that is expected to
reduce hospitalization considerably and allow for timely          II. MEC- BASED A RCHITECTURE FOR S MART H EALTH
delivery of healthcare services to remote communities at            We now give a brief description of the proposed MEC-
low costs.                                                        based architecture for e-health applications, and discuss
   S-health systems will also leverage various wireless           the benefits that it offers to s-health systems.
sensors, cameras, and controllers, which permit patients’
automatic identification and tracking, correct drug–patient       A. MEC-based S-Health Architecture
associations, and intensive real-time vital signs monitoring         The proposed system architecture, shown in Figure 1,
for early detection of clinical deterioration (e.g., seizure      stretches from the data sources located on or around
                                                                               Edge
                                                                               Cloud
                                                                                                                                                                e
                                                                                                                                                              ns
                                                                                                                                                         po
             Smart Home
                                                                                                                                                   R   es
                                                                                                                                            n   cy
                                                                                                                                       ge
                                                                                                                                  er
                                                                                                                             Em
                                    MEN
                                                                                                    Data
                          PDA                                                                              Raw data                                                                    Doctor
                                                                                                                            Data                                    Knowledge
                        Data                            Feature    Event     Adaptive    MEC
                                                                                                    Data
          EEG                                                                                              Compressed   Reconstruction
                                     Data
                                                                                                                                                                    Discovery
    ECG                                     Raw data   Extraction Detection Compression Optimizer
                                                                                                              data
                      Acquisition                                                                                            Classification
                                                                                                                                                                                      Emergency Response
                                                                                                           Features
                                                                                                    Data
     SpO2 Pulse
Accelerometer
                                                                                                                                                                                         Patients' Relatives
                                                                                                                                                                                        and other Followers
patients to the service providers. It contains the following                               patient’s state) and wireless network conditions.
major components:                                                                             Edge Cloud: It is a local edge cloud where data storage,
   Hybrid sensing sources: A combination of sensing de-                                    sophisticated data analysis methods for pattern detection,
vices attached/near to the patients represent the set of data                              trend discovery, and population health management can be
sources. Examples include: body area sensor networks (in-                                  enabled. An example of the edge cloud can be a hospital,
cluding implantable or wearable medical and non-medical                                    which monitors and records patients’ state while providing
sensors), IP cameras, smartphones, and external medical                                    required help if needed.
devices. All such devices are leveraged for monitoring pa-                                    Monitoring and services provider: A health service
tients’ state within the smart assisted environment, which                                 provider can be a doctor, an intelligence ambulance, or
facilitates continuous-remote monitoring and automatic                                     even a patient’s relative, who provides preventive, curative,
detection of emergency conditions. These hybrid sources                                    emergency, or rehabilitative healthcare services to the
of information are attached to a mobile/infrastructure edge                                patients.
node to be locally processed and analyzed before sending
it to the cloud (see Figure 1).                                                            B. Benefits for s-health
   Patient Data Aggregator (PDA): Typically, the wire-                                        Given the characteristics and requirements of e-health
less Body Area Network (BAN) consists of several sensor                                    applications, Table I summarizes some of the e-health
nodes that measure different vital signs, and a PDA which                                  systems that can benefit from the above architecture. It
aggregates the data collected by a BAN and transmits it to                                 is not the objective of this paper to provide an in depth
the network infrastructure. Thus, the PDA is working as a                                  technical comparison on the different proposed e-health
communication hub that is deployed near to the patient to                                  systems. However, we investigate the practical benefits of
transfer the gathered medical data to the infrastructure.                                  leveraging MEC in such systems. In what follows, we will
   Mobile/Infrastructure Edge Node (MEN): Herein,                                          discuss the advantages of the proposed MEC architecture
a MEN implements intermediate processing and storage                                       in the light of these systems.
functions between the data sources and the cloud. The                                         1) Monitoring systems using wearable devices: Heart
MEN fuses the medical and non-medical data from dif-                                       monitoring applications are the most common type of
ferent sources, performs in-network processing on the                                      remote monitoring applications. Monitoring vital signs
gathered data, classification and emergency notification,                                  related to the heart reveals many types of diseases, e.g.,
extracts information of interest, and forwards the processed                               Cardiac arrhythmia, chronic heart failure, Ischemia and
data or extracted information to the cloud. Importantly,                                   Myocardial Infarction [2][3][4]. In [2], authors present
various healthcare-related applications (apps) can be im-                                  a real-time heart monitoring system, where the extract
plemented in the MEN, e.g., for long-term chronic disease                                  medical data of the patients are transmitted to an Android
management. Such apps can help patients to actively                                        based listening port via Bluetooth. Then, this listening
participate in their treatment and to ubiquitously interact                                port forwards these data to a web server for processing.
with their doctors anytime and anywhere. Furthermore,                                      Also, [3] exploits Android smartphone to gather patient’s
with a MEN running specialized context-aware processing,                                   information from wearable sensors and forward it to a web
various data sources can be connected and managed easily                                   portal in order to facilitate the remote cardiac monitoring.
near the patient, while optimizing data delivery based on                                  However, in these systems, the smartphone is used only
the context (i.e., data type, supported application, and                                   as a communication hub to forward collected data to the
                                                                  TABLE I
                                               S UMMARY OF THE E - HEALTH RELEVANT SYSTEMS .
      Application              Collected Data                           Description                     Limitations            MEC Benefits
     Cardiac disorder        Electrocardiography        Heart monitoring system is developed        All data processing        Data reduction
      detection [2]                 (ECG)                  for detecting status of the patient      tasks are performed        and BW saving
                                                             and sending an alert message             at a web server
                                                                 in case of abnormalities
                                                            Requirements: long lifetime for
                                                              the battery-operated devices
     Remote Cardiac              Heart rate               A location based real-time Cardiac          Fewer number of            Location
     monitoring [3]            blood pressure               monitoring system is developed          subjects participated      Awareness and
                              body temperature              Requirements: long lifetime for          in the experiments        energy saving
                                                              the battery-operated devices
  Detection of Ischemia      ECG and Electronic        Presenting different methods leveraged     Majority of the reviewed     Data reduction
     and Myocardial         Health Records (EHR)          ECG signal with EHR information         literature did not exploit   and BW saving
      Infarction [4]                                           to detect Ischemia and MI           contextual information
                                                           Requirements: low computational
                                                                        complexity
 Parkinson’s disease (PD)        Voice signal          A PD monitoring system over the cloud        All data processing        Data reduction
       detection [5]                                   is proposed using feature selection and      tasks are performed        and BW saving
                                                             classification of a voice signal           at the cloud
                                                          Requirements: Reliability and high
                                                                  classification accuracy
  Contactless heart rate          Heart rate             Heart rate measurement from facial        Illumination variance,      Data reduction
    measurement [6]                                       videos using digital camera sensor       motion variance, and        and BW saving
                                                          Requirements: Reliability and high           motion artifacts
                                                                  measurement accuracy
      Prediction of                 ECG                  Leveraging point process analysis of       Using single-channel        Low latency
  Bradycardia in preterm                                  the heartbeat time series to predict      ECG data to predict
       infants [7]                                         infant Bradycardia prior to onset            Bradycardia
                                                            Requirements: Fast prediction of
                                                                   emergency situations
    Real-time epileptic     Electroencephalography      Automatic epileptic seizure detection      Requiring large amount       Low latency
   seizure detection [8]            (EEG)                system using wavelet decomposition           of data for training
                                                                        is proposed                 to improve specificity
                                                         Requirements: Fast seizure detection           of the detector
      ECG change                    ECG                A centralized approach for the detection    Using one type of data       Low latency
      detection [9]                                        of abnormalities and intrusions in     for detecting abnormality
                                                               the ECG data is developed          and emergency situations
                                                            Requirements: Fast detection of
                                                                       abnormalities
  Remote monitoring of       Pulmonary Function         Real-time tracking system of chronic        Relying on one type         Low latency
   chronic obstructive           Test (PFT)               pulmonary patients comfortable in               of data
     pulmonary [10]                                     their home environment is developed
                                                            Requirements: Fast detection of
                                                                       abnormalities
cloud. Hence, continuous data transmission is not viable                patient’s activities [6]. However, transmitting large vol-
due to the high energy toll it implies. The advantages of               umes of data generated from these camera sensors using
implementing the proposed MEC architecture in such sys-                 conventional cloud-based architecture is not advisable and
tems are twofold. First, energy saving can be significantly             may deem some of these applications impractical given the
increased by carefully managing the devices operational                 limited bandwidth availability. For instance, the amount
state and their data transfer at the MEN. In addition, data             of digital data generated from a single-standard camera
compression as well as the proximity between sensors                    can reach to 40 GB per day. Accordingly, processing,
and MEN further reduce the energy consumption due to                    compressing, and extracting most important information
data transmission [11][12]. Second, the network edge can                from the gathered data at the MEN greatly reduce the
be fruitfully exploited to extract context information and              amount of data to be transferred toward the cloud, hence
apply localization techniques, which allows matching the                the bandwidth consumption, and even makes it possible to
patient’s geographical position with the nearest appropriate            store the data locally.
caregivers (e.g., hospital or ambulance).
                                                                           3) Disorder prediction/detection systems: One of the
   2) Contactless monitoring systems: Along with the                    promising applications of s-health, is the predictive mon-
evaluation of remote sensing, contactless monitoring has                itoring of high-risk patients. The aim of these techniques
attained much focus recently. The main motivation of                    is improving prediction/detection of the emergency to
using contactless sensors is enabling ordinary life as much             implement preventative strategies for reducing morbid-
comfortable as possible to all patients, since the patients             ity and mortality associated with high-risk patients. For
are required only to be present within a few meters from                instance, [7] presented a simplistic framework for near-
the sensors [5]. Heart rate measurement from facial videos              term prediction of Bradycardia in preterm infants using
using digital camera sensors is one of the rapidly growing              statistical features extracted from ECG signal. Also, [8]
directions to extract physiological signals without affecting           proposed a quick seizure detection algorithm using fast
wavelet decomposition method. In such real-time predic-              Our solution leverages deep learning, which is a good
tion/detection systems, the swift delivery of data to the        candidate for multimodal data compression due to its abil-
server is a necessity. In many cases, this requires that data    ity to efficiently exploit, not only the intra-modality cor-
are analyzed and even a diagnosis is made as close as            relation, but also inter-correlation among different modal-
possible to the patient. However, detecting the changes of       ities. Specifically, we use Stacked Auto-Encoders (SAE),
the physiological signals (e.g., changing in ECG values) in      i.e., a special type of neural networks allowing for the
continuous health monitoring systems is not an easy task.        hierarchical extraction of data representation [13]. SAE
It can be an indication for an emergency situation (e.g.,        consists of two main layers: (i) the encoding layers where
occurrence of a heart attack) [9][10]. This abnormality          the data features are extracted, and (ii) the decoding layers
detection task becomes even more challenging during              where the signal is reconstructed from the data coming
wireless communication transfer of patient’s data to the         from the encoding layers. In our case, we implement the
cloud due to the erroneous communication and security            encoding layers at the MEN, while the decoding layers
attacks that could introduce errors or makes changes in the      are placed at a server in the cloud. Our key idea is to
patient’s data. Hence, quick detection of the changes in the     progressively reduce the number of neurons in each of the
gathered medical data at the MEN is essential for real-time      encoding layers at the MEN, and make the neural network
abnormal event detection. In a nutshell, the implementation      learn from compressed version of the data. As a result,
of MEC architecture addresses all these issues, and the          through the last encoding layer at the MEN (i.e., the one
ability of the MEN to perform event detection/prediction         with the least number of neurons), we obtain a set of
fulfills these requirements even in the case of emergency        features that are a compressed representation of the initial
applications.                                                    data. In summary, at the MEN, our SAE encoder converts
                                                                 the input data x into the compressed data z, provided by
  III. I MPLEMENTING THE E DGE N ODE F UNCTIONS                  the last encoding layer. At the server side (in the cloud),
   The ultimate goal of our MEC architecture is to fulfill       the SAE decoding layers will obtain the reconstructed data
the different requirements of e-health applications men-         x̃, using the compressed representation z. The compressed
tioned above and enable s-health services through imple-         and reconstructed signals can be written as:
menting the following main functionality at the network
edge:                                                                                   z = Wx + b                        (1)
   • data compression, in order to reduce energy and band-
                                                                                        x̃ = W̃ z + b̃.                   (2)
     width consumption in the case of health monitoring
     systems;                                                    where W and W̃ are the encoder and decoder weights
   • feature extraction and classification, in order to ensure   matrices, respectively, while b and b̃ are the bias vectors.
     high-reliability and fast response time in disorder            The objective of SAE is to find the optimal configuration
     prediction and detection.                                   of the weight matrices and bias vectors that minimize
Below, we present how the above functionality can be             the reconstruction error. In our case, instead, we first set
implemented at the MEN and highlight the benefits that           the number of neurons in the last layer at the encoder,
the MEC architecture can bring.                                  according to the desired compression ratio. Then we
                                                                 optimize the number of neurons to be placed in each of
A. Multimodal data compression using deep learning               the other encoding layers. Finally, by training the neural
   The conventional approach used for health monitoring,         network, we determine the optimal weight matrices and
i.e., transmitting the entire medical data wirelessly to         bias vectors. We remark that, although the network training
the cloud, implies the transfer of a massive amount of           is a computational expensive task, it can be conducted
data. For instance, in brain disorder monitoring systems,        offline at the server side. Then such a configuration can be
EEG, Electromyography (EMG), and Electrooculography              sent and used at the MEN for on-line data compression,
(EOG) data need to be stored and accessed remotely,              thus leading to low-complexity, on-line data compression
along with video recording patient’s activities, in order to     and transfer.
correlate the patient’s activities with her EEG pattern. This       The advantages of multimodal data over single modality
would result in generating 8-10 GB per patient per day. A        compression are twofold. First, we can account for inter-
promising methodology to deal with this issue in s-health        modality correlation during compression, which results in
systems is to perform local in-network and data-specific         a lower distortion while reconstructing the signal. Sec-
compression on the gathered data before transmission,            ond, by concatenating the different modalities (i.e., EEG
while taking into account the applications’ requirements         and EOG signals), it enables encoding the modalities in
and the characteristics of the data.                             a single-joint representation (i.e., the single stream z).
   Here, we consider the EEG-EOG monitoring system as            Figure 2 compares the proposed multimodal SAE (M-
a case study and present an efficient technique that deals       SAE) with the Single Modality (SM) compression scheme,
with multimodal data, as required by s-health applications.      which compresses each signal separately using SAE. As
In particular, we use the multimodal dataset in [13],            the compression ratio varies, we observe that multimodal
which contains EEG and EOG signals of 32 people, who             SAE allows for up to 50% reduction in EEG distortion
volunteered for this experiment, watching to 40 music            with respect to SM, while EOG distortion increases by
videos.                                                          just 2%.
                 50
                        M-SAE EEG                                                                                PDA
                        M SAE EOG                                                                                                         Transmit
                                                                                                                                                      Data
                 45
                        SM EEG                                                                                                            Raw Data
                 40     SM EOG                                                              Data         Feature         Swift
                                                                                         Acquisition    Extraction   Classification
                                                                                                                                           Transmit
Data
                                                                                                                                                             EEG Features
                 35
                                                                                                                                                                            Raw Data
                                                                                                                                           Features
  Distortion %
                 30
                                                                                                                 Cloud
                 25                                                                                                               Classification
                 0
                  10   20     30    40     50     60      70   80   90     EEG data into the frequency domain, the normal/abnormal
                                    Compression Ratio %
                                                                           EEG classes under study exhibit different mean, median,
Fig. 2. Signal distortion as a function of the compression ratio for EEG   and amplitude variations. Also, Root Mean Square (RMS)
and EOG signals, using M-SAE and SM compression schemes.
                                                                           and Signal Energy (SE) are good signal strength estimators
                                                                           in different frequency bands. Hence, to distinguish between
                                                                           seizure and non-seizure events we select the following
B. Edge-based feature extraction and classification
                                                                           five Frequency Features (FF): mean (µ), median (M), peak
   Many neurodegenerative diseases detection methods,                      amplitude (P), RMS, and SE.
such as Parkinson’s, Epilepsy, Alzheimer’s, and Hunt-                         2) Event-detection at the edge : The second step in
ington’s, have been reported in the literature based on                    our procedure consists in developing a reliable, edge-based
extracting some features from the patients’ vital signs,                   classification technique for seizure detection leveraging the
voice, or captured videos. Such features are used to dif-                  extracted features [15]. A number of machine learning
ferentiate a potential patient from a healthy person, or to                techniques, including supervised, unsupervised and rein-
identify emergency situations. For instance, [5] proposes                  forcement learning, have been investigated for the purpose
a method to detect Parkinson’s disease (PD) leveraging                     of classification, for a variety of applications. In a nutshell,
certain features of the voice signal using cloud computing.                supervised learning algorithms leverage a labeled training
Specifically, at the cloud server, the voice signal features               data set to learn the relation between inputs and outputs.
are extracted and used for classification; the results are                 In contrast, unsupervised learning algorithms classify the
then sent to registered doctors for proper action.                         provided data sets into different clusters by discovering
   In our study, we focus on epileptic seizure detection and               the correlation between input samples. The third category
show the advantages of implementing feature extraction                     includes reinforcement learning algorithms and exploits
and classification at the MEN for efficient transmission and               online learning, which involves the exploration of the
fast detection of abnormalities. We assume that the MEN                    environment and the exploitation of current knowledge,
gathers EEG data from the patient using an EEG Headset,                    in order to classify the data [16]. However, some im-
processes the data, and forwards them to the cloud. We                     portant issues arise when machine learning techniques
now use the EEG dataset in [14], which comprises three                     are applied to s-health: (i) an optimal trade-off between
classes of data, in the following denoted by A, B, and                     algorithms computational complexity and classification ac-
E, respectively. Each class contains 100 EEG records                       curacy should be established, (ii) sufficiently large datasets
corresponding to different patients. Each record includes                  have to be considered, in order to ensure high accuracy,
samples collected for 23.6 seconds at a 173.61 Hz rate. Sets               (iii) a mathematical formulation of the learned model, as
A and B represent seizure-free subjects with eyes opened                   well as full control over the knowledge discovery process,
(A) and closed (B), respectively, while set E contains data                is hard to obtain.
related to epileptic patients.                                                In the considered case study, we define an IF-THEN
   Using such data, we first perform feature extraction and                classification rule using generated FF to detect abnormal
classification at the MEN. Then, depending on whether                      variations in sensed EEG data due to seizure. Thus, the
a seizure event was detected through classification, the                   status of the patient, S, is given by:
system sends to the cloud server the all data, or only
                                                                                      (
                                                                                         Normal if µ+M +P +RM S+SE ≤ γ
the computed features. Figure 3 summarizes the proposed                           S=
key concept. Below, we describe an efficient technique for                               Seizure if µ+M +P +RM S+SE > γ
feature extraction in Sec. III-B1, then we address event                   where γ is the classification threshold obtained during
detection and classification in Sec. III-B2.                               the offline training phase. Thus, leveraging the proposed
   1) Feature extraction : In order to carry out the first                 low-complexity classifier, a quick emergency notification
step of our procedure, two approaches can be imple-                        system can be implemented at the edge to notify patient’s
mented: time-domain and frequency-domain feature ex-                       caregivers in case of emergency, as well as doctors at the
traction. Herein, we consider the frequency-domain ap-                     remote site.
proach due to its insensitivity to signal variations resultant               In Figure 4, we compare the accuracy of the proposed
from electrode placement. By transforming the gathered                     Frequency Features Classifier (FFC) against that of differ-
                                                                                          100
ent machine learning approaches, including random deci-                                                                                     CBS
                                                                                           90
sion forests (RandomForest), Naive Bayes (NaiveBayes),                                                                                      FFC
Fig. 4. Comparison of the proposed FFC technique with respect to     B. Collaborative edge
RandomForest, NaiveBayes, IBk, and REPTree algorithms, in terms of
classification accuracy, with varying γ.
                                                                        Healthcare requires data sharing and collaboration
                                                                     among different stakeholders in multiple domains. How-
                                                                     ever, sharing of data owned by a stakeholder rarely hap-
         IV. C HALLENGES AND O PPORTUNITIES                          pens due to privacy concerns and the high cost of data
                                                                     transfer. In this context, collaborative edge, which con-
  In this section, we discuss three main challenges and op-          nects the edges of multiple stakeholders that are geographi-
portunities that characterize MEC-based s-health systems             cally distributed (such as hospitals, centers for disease con-
and represent interesting lines for future research.                 trol and prevention, pharmacies, and insurance companies),
                                                                     is beneficial in threefold. First, it provides distributed
A. privacy and security                                              data sharing among different stakeholders at low cost,
   Great potential of s-health system can only be achieved           thanks to computation and processing at the participant
if individuals are confident about the privacy of their              edges. Second, in the case of remote monitoring, it enables
health-related information and providers are confident               patients to forward their medical data to the cloud through
about the security of gathered data. However, ensuring               other users/edge nodes. This also improves spectrum and
energy efficiency and allows data transferring even in ge-      acquired data, and high level requirements of the consid-
ographically remote areas by exploiting D2D data transfer       ered application should be integrated in order to provide
[19]. Third, it enables a patient’s edge node to directly       sustainable and high-quality services for s-health systems.
connect to the nearest hospital’s edge in the proximity for     In this context, we identified some computing tasks that
continuous monitoring, without the need of going through        can be implemented at the edge and presented effective
the cloud. This helps to increase monitoring efficiency,        approaches to implement them, so as to ensure short
reduce energy consumption and operational cost, as well         response time, efficient processing and minimal energy
as improve high-quality services.                               and bandwidth consumption. Finally, we highlighted some
                                                                challenges and opportunities of edge computing in the s-
C. Combining heterogeneous sources of information               health field that are worth further research.
   Various sources of information are used in S-health
systems for efficient monitoring, hence, leveraging ad-                                ACKNOWLEDGMENT
vanced multimodal data processing techniques for com-
                                                                  This work was made possible by GSRA grant # GSRA2-
bining these sources of information at the edge is a
                                                                1-0609-14026 from the Qatar National Research Fund (a
promising trend toward automating supervision and remote
                                                                member of Qatar Foundation). The work of Amr Mohamed
monitoring tasks. However, several challenges remain open
                                                                and Alaa Awad Abdellatif is partially supported by NPRP
when it comes to the s-health systems with hybrid sensing
                                                                grant # 8-408-2-172. The findings achieved herein are
sources. First, in terms of multiple modalities, it is not
                                                                solely the responsibility of the authors.
straightforward to incorporate and transmit multiple data
streams in s-health systems, where power consumption is a
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