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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>IoT based End-to-End Farm Management System: An Approach toward Industry 4.0</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Eleni Symeonaki</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Konstantinos Arvanitis</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dimitrios Piromalis</string-name>
          <email>piromali@uniwa.gr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michail Papoutsidakis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Industrial Design and Production Engineering, University of West Attica</institution>
          ,
          <country country="GR">Greece</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens</institution>
          ,
          <country country="GR">Greece</country>
        </aff>
      </contrib-group>
      <fpage>377</fpage>
      <lpage>384</lpage>
      <abstract>
        <p>The Industry 4.0 concept is a prominent trend expected to significantly affect the modernization of all industrial sectors. Since agriculture is a major sector of the primary industry, it is essential to integrate the Industry 4.0 technological advancements into the operational farm management in order ensure food security with regard to the climate change effects and the sustainable usage of environmental resources. Provided that the Industry 4.0 is strongly tied to the Internet of Things (IoT) technology, this paper presents an approach of employing a responsive and adaptive context sensitive IoT based system, capable of delivering a wide variety of operational services in order to facilitate end-to-end farm management. In particular, the proposed approach adopts a layered hierarchical structure enhancing the scalability and flexibility of agricultural operations. As proof of concept, the functionality of the proposed system was evaluated and some results regarding its performance are quoted.</p>
      </abstract>
      <kwd-group>
        <kwd>Industry 4</kwd>
        <kwd>0</kwd>
        <kwd>Internet of Things</kwd>
        <kwd>Farm Management</kwd>
        <kwd>Sustainability</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>
        The Industry 4.0 concept, which was originally introduced by the German National
Academy of Science and Engineering
        <xref ref-type="bibr" rid="ref3">(Kagermann et al., 2013)</xref>
        , represents, as reported
in the 2016 meeting of the World Economic Forum
        <xref ref-type="bibr" rid="ref14">(WEF, 2016)</xref>
        , a prominent trend
expected to significantly affect the modernization of all industrial sectors
        <xref ref-type="bibr" rid="ref13 ref7">(Xu et al.,
2018; Pfeiffer, 2017)</xref>
        by promoting a framework for the integration of the entire
production process into a “smart” digitalized environment. In this sense, since
agriculture is a major sector of the primary industry, it is essential to integrate the
Industry 4.0 technological advancements into the operational farm management, in
order to address the excessive challenge of ensuring food security for the constantly
increasing world population with regard to the climate change effects and the
imperative necessity for long-term sustainable usage of environmental resources
        <xref ref-type="bibr" rid="ref10 ref9">(Symeonaki et al., 2017; Sørensen and Bochtis, 2010)</xref>
        .
      </p>
      <p>
        Farm Management Systems (FMSs) are of fundamental importance for the
accomplishment of successful farm management as they involve functions for
planning, organizing, monitoring and controlling agricultural operations. To improve
the performance of these activities in terms of sustainability, FMSs should be
competent [8-10] to
        <xref ref-type="bibr" rid="ref2 ref6">(Ozdogan et al., 2017; Deichmann et al., 2016)</xref>
        :
i) Enact more efficient and sophisticated automated agricultural operations
(such as cultivation, monitoring, irrigation, etc.) in complex
environments and farm structures at lower costs,
ii) Provide effective and secure operating conditions both for the
environment and agricultural stakeholders (such as farmers, agronomist
engineers, policy makers, development cooperation professionals, etc.),
iii) Enhance the synergies among all agricultural stakeholders providing
them with the ability to make decisions even on matters that are outside
their areas of expertise.
      </p>
      <p>
        Current FMSs are generally in accordance to a specific business model
        <xref ref-type="bibr" rid="ref9">(Sørensen
and Bochtis, 2010)</xref>
        and their operations do not exceed the limit of agricultural data
monitoring as well as the delivery of selected control services through standalone
applications, which are tightly integrated with each system since they involve closed
specifications for commercial infrastructures and address to targeted end-users. This
imposes some significant constraints concerning the interoperability of the FMSs as
well as the semantic annotation of the numerous heterogeneous agricultural data that
need to be handled by them. For this, a generalized approach of end-to-end farm
management, based on the potent cross-industry cooperation of infrastructures,
technologies, applications and stakeholders, is significant to be applied in accordance
with the objectives and guidelines for the operative implementation of Industry 4.0
        <xref ref-type="bibr" rid="ref11">(Symeonaki et al., 2020)</xref>
        , as depicted in Fig.1.
      </p>
      <p>
        Provided that the Industry 4.0 concept is considered to be a “collective” term
through the establishment of a digitalized environment wherein physical and virtual
objects can interconnect and interact autonomously along the entire value chain
        <xref ref-type="bibr" rid="ref7 ref8">(Pfeiffer, 2017; Rojko, 2017)</xref>
        , it is strongly tied to the technology of the Internet of
Things (IoT). In all industrial sectors, among which is agriculture, the IoT integrates
the concepts of “Internet” and “thing” offering some key features such as
heterogeneity, interoperability, high scalability, interconnectivity, object-related
services as well as dynamic changes
        <xref ref-type="bibr" rid="ref12 ref5">(Lakhwani et al., 2019; Madushanki et al., 2019;
Talavera et al., 2017;)</xref>
        . In particular, according to the IoT concept, an intelligent
network, such as the Internet, is employed as a communication and storage
infrastructure comprising virtual representation of the physical objects features and
attributes. In this context the virtual objects act as central object information hubs,
continuously acquiring and processing data from the physical environment in order to
control operational processes remotely via the Internet
        <xref ref-type="bibr" rid="ref1">(Bonneau et al., 2017)</xref>
        .
      </p>
      <p>This paper is keen to present an approach of employing a responsive and adaptive
context sensitive IoT based system, capable of delivering a wide variety of operational
services in order to facilitate end-to-end farm management. To this end, the proposed
approach adopts a layered hierarchical structure consisting of an agricultural facility at
the lower level and three cloud components distributed into the two higher levels. It is
considered that such an approach will consequently enhance the scalability and
flexibility of agricultural operations, by handling simultaneously large amounts of
heterogeneous sensory raw data acquired remotely in multiple agricultural
environments, and support the control of infrastructures as well as the making of
critical decisions related to the optimization of agricultural production with regard to
the sustainable development.</p>
      <p>Subsequently to the introduction in Section 1, the rest of this paper is structured in
five sections as follows. Section 2 overviews the architectural framework of the entire
FMS while in Section 3 the operational functionality of the system is described in brief.
In Section 4 the performance of the system is examined and some evaluation results
regarding its performance are quoted in general. Finally, the paper is completed in
Section 5, wherein the principal conclusions drawn from this work are discussed along
with future directions for further research.</p>
    </sec>
    <sec id="sec-2">
      <title>2 FMS Architectural Framework Overview</title>
      <p>In the proposed architectural framework, the IoT acts as the enabling technology
for efficient end-to-end farm management in order to ensure maximum agricultural
production of optimum quality and increase the profitability of various agricultural
production schemes. According to this framework the FMS consists of three main
layers as depicted in Fig. 2 and overviewed forth below.</p>
      <sec id="sec-2-1">
        <title>2.1 Physical Layer</title>
        <p>The lower level points the Physical Layer, which involves a Wireless Sensor and
Actuator Network (WSΑN) integrated in an agricultural facility, consisting of a group
of self-powered sensor nodes deployed in a mesh network topology with adequate
communication range to cover a wide area. These nodes incorporate sensors that
remotely acquire real-time data about various features concerning the cultivation, as
well as actuators that interact with them, enabling the proper physical actions within
the facility. The raw data acquired by the WSAN sensors are transmitted via
wireless/mobile gateways, providing the required translation technologies and
mechanisms among various protocols, to the next higher layer for being processed,
managed, and stored. Subsequently, the gateways serve the transmission of feedback
to the actuator nodes of the WSAN in order to control the equipment of the agricultural
facility (i.e. irrigation valves, fertilizing sprinklers, illuminance and heating or cooling
systems, autonomous machinery, foggers and humidifiers, etc.) and perform the
required agricultural operations.</p>
        <p>The Middleware Layer of the proposed architectural framework involves a
contextaware middleware cloud acting as a Decision Support System (DSS) in order to
provide context-aware services and actions. This component adopts the Infrastructure
as a Service (IaaS) properties of cloud computing and is composed from several
modules for acquiring, managing, and storing contextual data. Great importance is also
given to the aspects of self-adaptation as well as security and privacy.</p>
        <p>In particular the context acquisition module is responsible for the aggregation of the
raw data which were obtained by the sensors of the facility’s WSAN and their
distribution among various providers (i.e. a weather station providing context related
to environmental conditions such as temperature, pressure, humidity, etc.) so as to be
converted into context. The context manager is responsible for managing requests from
the context acquisition module, where contextual information is being obtained, as
well as for correlating the contexts with the services which are specified by the service
providers in order to identify the most suitable services and control actions for the
relating context. The context storage module is highly required since context history
can be essential for process planning, constituting a good source of knowledge for
prediction of future actions to be undertaken and inference processes. Finally, the
security and privacy module ensure the privacy of contextual information, through the
execution of security functions which detect and monitor possible irregularities or
unauthorized accesses to data. On top of that the self-adaptation module is responsible
for diagnosing, locating and recovering any possible failures in the workflows.
2.3</p>
      </sec>
      <sec id="sec-2-2">
        <title>Application Layer</title>
        <p>The Application Layer of the proposed FMS consists of two cloud components
which involve Software as a Service (SaaS) features. In particular in this layer all the
required software applications for the interaction of end user with the FMS are
provided, such as real time monitoring and facility equipment control. The applications
are centrally hosted, accessed by users remotely and licensed on a subscription basis.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>FMS Operational Description</title>
      <p>In the proposed FMS approach sensor data, acquired by a Wireless Sensor and
Actuator Network (WSΑN) in an agricultural facility, are transmitted via a gateway as
raw data to the context-aware middleware cloud where they are converted to context.
These contextual data as well as the incoming rules provided by the services cloud
(containing applications for the end user) are managed inside the middleware
component to produce monitoring information, services and control actions (such as
cultivation control). The context-aware middleware cloud responds back to the
agricultural facility enabling the appropriate equipment to perform context-aware
operations as well as back to the end users (farmers, agronomist engineers and
agricultural products merchants) providing them with new context-aware services and
monitoring information in order to take further assistive actions. In this sense the end
user can operate the agricultural facility remotely via the cloud services (Fig. 3). It
should be noted that this system’s architectural framework may apply to more than one
agricultural facility.
Fig. 3. End-to- End Farm Management System operational overview.
4</p>
    </sec>
    <sec id="sec-4">
      <title>FMS Performance Evaluation</title>
      <p>With the objective to validate the performance of the FMS a number of trials were
conducted both in real and simulated environment for one agricultural facility
environment. Testing the system allowed its proper analysis and evaluation in terms
of health, operation, and performance.</p>
      <p>In general, according to the outcomes provided by the metrics obtained during the
tests as depicted in Fig. 4, the proposed FMS performs fairly satisfactory for
controlling one agricultural facility environment since sensory data could be
adequately acquired, processed, stored in the knowledge base, retrieved and
disseminated to the applications of interest, resulting consequently into the proper
actions. Nevertheless, the performance of the system is intended to be more thoroughly
tested by evaluating additional parameters and integrating multiple agricultural
environments for various cultivations and in distinct locations as part of future
research.</p>
    </sec>
    <sec id="sec-5">
      <title>5 Conclusions and Future Work</title>
      <p>In conclusion, it is strongly believed that the proposed FMS architectural framework
may support the integration of farm management toward the Industry 4.0 concept. It is
in that regard that the introduced approach, based on the integration of WSANs into
the IoT, has the benefit of being effortlessly adaptable, modifiable, and extendable for
any application in any agricultural system environment no matter how complex it is.</p>
      <p>Future work on the subject is intended to include an in-depth performance
evaluation of the model through the integration of multiple agricultural facility
environments with various cultivations and in distinct locations, in order to improve
the interoperability and standardization of the proposed framework. For what is more,
since the involvement of smart mobile devices and social networking was not taken
into much consideration, these features are going to be included as part of the ongoing
work.</p>
    </sec>
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