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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>DROVIDS: A Platform for Workplace Safety</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Juris Tihomirovs</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ralfs Matisons</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rolands Zaharovs</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>DTG, Ltd.</institution>
          ,
          <addr-line>Ganību dambis 24A, Riga</addr-line>
          ,
          <country country="LV">Latvia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Riga Technical University</institution>
          ,
          <addr-line>6A Kipsalas Street, Riga LV-1658</addr-line>
          ,
          <country country="LV">Latvia</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <fpage>23</fpage>
      <lpage>26</lpage>
      <abstract>
        <p>The Covid-19 pandemic has transformed the dynamics of workforce and workplace. Being affected by Covid-19, organizations had to mitigate the risks of workplace safety and their negative effects on the health of employees and society. The workplace conditions, such as optimal CO2 level, humidity, are essential factors to ensure the safety and wellbeing of the employees. A safe work environment and the wellbeing of the employees are catalysators of enterprise productivity and sustainability, and advanced digital technologies help to achieve these objectives. This paper describes an applied project on development of a platform for monitoring and controlling workplace conditions to reduce risks of infectious diseases as well as other adverse effects on workforce productivity. It focuses on platform design using the C4 design model. The platform combines conventional and less frequently used data sources, such as wastewater analysis, to evaluate the risk of infectious diseases and to interpret these in the organizational context.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Infection safe workplace</kwd>
        <kwd>Covid-19</kwd>
        <kwd>IoT</kwd>
        <kwd>sensors</kwd>
        <kwd>C4 modeling</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The Covid-19 pandemic has created various challenges for organisations. They had to
significantly change their operating patterns to avoid interruptions in supply chain, adapt
services to customer demand and mitigate risks to working safety and their negative
effects on the health of employees and society in general. The World Health Organisation
emphasizes the importance of a safe working environment [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. A safe workplace is an
essential factor in limiting the spread of infection. Estimating employee health, maintaining
safe distances between workers, and monitoring contacts among all employees to separate
them in the case of infection with SARS-COV-2 or other contagious diseases are important
for the maintenance of the economic sector [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The safe working environment is
particularly important for organizations that, due to their specific nature, cannot resort
fully to remote work. It is a prerequisite for maintaining their businesses and jobs in order
to mitigate the economic recession at the national and global levels during the pandemic
situation.
      </p>
      <p>The safe workplace consists of many factors that include both the regulation of human
resources and environmental resources. Through the combination of monitoring the
environment around employees and the monitoring of employees, it is possible to create a
safer work environment, but in order to do this, an autonomous solution is required, which
could always be available.</p>
      <p>
        During the epidemic, important contributions have been made to the identification,
tracking, and prevention of Covid-19. The use of IoT to ensure a safe workplace for
infections has been widely used [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]–[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] both in health surveillance monitoring [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]–[
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] and
in building and facilities management [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], [10], as it has the ability to sense, share and
transfer data through the network of interconnected devices. Although several similar
solutions exist, they primarily cover one of the risk factors, such as air quality monitoring
or monitoring of compliance with the distancing requirements. Monitoring models cannot
be supplemented with new diffusion models and risk factors. The solutions do not provide
recommendations for adjusting the set of measures according to the company topology.
The existing solutions do not include early warnings about the approaching potential
outbreaks, which are essential for enterprises to be able to limit outbreaks as soon as
possible.
      </p>
      <p>The project aims to create a platform for a safe working environment (referred to as
DROVIDS) that integrates advanced information and communication technologies and
biotechnologies. The platform combines business continuity planning, IoT, computer
vision, machine learning and wastewater analytics technologies for comprehensive
Covid19 and other infections risk assessment, mitigation and prevention in workplaces where
the nature of work limits remote working options, such as shift-based manufacturing
companies. This paper describes an approach to ensure safe work environment and
presents the design of the DROVIDS platform.</p>
      <p>The rest of the paper is organized as follows. Section 2 presents the research
methodology. Section 3 describes the overall approach of the platform. The design of the
platform is elaborated in Section 4. Section 5 concludes.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Research Methodology</title>
      <p>The Action Design Research (ADR) method [11] is used for the research design. The ADR
method requires a significant focus on the development of practical and theoretical
relevance of the research, allowing an iterative development process to assess different
design alternatives and combine different research methods. The method emphasises the
dissemination of research results. The essence of the method is the cyclical development
of project artefacts by conducting the main phases of the research (Figure 1): (1) problem
formalization, (2) building, intervention and evaluation, (3) reflection and learning and (4)
formalization and learning. All phases are primarily focused on the development of a new
artefact, the DROVIDS platform.</p>
      <p>The problem investigation relies on gained knowledge from the implementation of
previous projects by the project partner - software development company DTG. It has been
consolidated in the product development roadmap of DTG, which provides analytical
solutions for improving the work environment of the enterprises. The empirical evidence
is supplemented by analysis of the related research and existing IT solutions in the
feasibility study of the project.
The main tasks of the project are related to the building, intervention, and evaluation of
the DROVIDS platform and its underlaying components (models and methods). The safe
work environment model is the foundation of the platform, and it consists of three main
building blocks: business continuity and risk assessment model, sensor model and
enterprise topology model. Information systems analysis methods [12], the enterprise
architecture framework TOGAF [13], 4EM method [14] and IDEF method [15] are used in
the development and conceptualization of the artefacts of the safe work environment
model. The enterprise architecture framework is used to describe high-level architecture
of a business continuity, while 4EM and IDEF are used for the description of lower level
architectural artefacts, such as an enterprise topology model. The platform is designed as
a distributed system using a microservice architecture. The design of the platform follows
the C4 model [16] which allows a gradual decomposition of the system, defining the main
components and designing and detailing the specific services sequentially. The C4 model
is an "abstraction-first" approach to diagramming software architecture, based on
abstractions that reflect how software architects and developers think about and build
software. The platform components are developed in the form of portable containers, and
standardised APIs are used to integrate them. The development process uses incremental
and iterative software development methods [17], which divide development into phases
with periodic tests and demonstrations to assess progress and provide feedback. The
evaluation of the platform is done in real operating conditions in the DTG office. Evaluation
is performed for all developed services and intended data types (CO2 and humidity level,
Covid-19 particle density in wastewater, application of restrictions). Physical
experimental planning methods [18] are used to implement experiments, and statistical
analysis and hypothesis testing methods [19] are used to process the results. The
validation is performed gradually, starting with the collection of data and continuing with
their analysis and development of recommendations.</p>
      <p>Reflexion and learning are performed by analysing DROVID evaluation data. The
evaluation results are used to adapt, adjust and formalize its underlying models and
methods. The research results are shared with the stakeholders in the form of scientific
papers, conferences presentations, and dissemination activities, such as demonstration of
the platform prototypes.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Overall Approach</title>
      <p>The central part of the platform is an integrated approach to managing infection risks in
organizations (Figure 2). It uses cross-disciplinary scientific methods to ensure the
nonintrusive and preventive minimization of infection risks. These sensor technologies
offer predictive and preventive capabilities. They are used in the organisational context to
improve the adaptation of mitigation measures and ensure business continuity.</p>
      <p>The platform uses IoT, waste water analysis data, and productivity data to gain a better
understanding of the environment of the office. Employee interactions are combined with
source information systems in a topology model. Having combined the data about the office
environment and the topology model the office premises can be evaluated more precisely,
keeping in mind such things as employee time spent together, etc. The risk assessment
allows us to understand the quality of the environment in the office, and whether the office
premises are more likely to spread malicious infections or not.</p>
      <p>The DROVIDS platform provides an opportunity for early warnings about the risks of
Covid-19 outbreaks by analysing the density of Covid-19 particles in the company's
wastewater. The platform collects data on the density of Covid-19 particles in the
wastewater and generates early warnings to responsible employees of the company. The
platform includes a business continuity planning and risk analysis model that uses data
from enterprise information systems (work management systems, project management
systems, space management systems, etc.). The risk model is elaborated in [20] and the
use of enterprise data and topology is presented in [21].</p>
    </sec>
    <sec id="sec-4">
      <title>4. Platform Design</title>
      <p>The initial DROVIDS architecture is shown in the C4 high-level System context diagram
(Figure 3). The architecture includes the following concepts: the Covid safe work
environment platform DROVIDS and integrations with external data sources, sensors,
actuators, and messaging services. In that architectural model, the DROVIDS platform
interacts with external building blocks and supports two different types of data flow:
• Incoming data for risk monitoring and analysis. Data from external data sources
and sensors are used for risk monitoring and analysis. The DROVIDS platform
receives data from related information systems – Covid-19 prevention legislation
database (provides safe work-space requirements), enterprise ticketing system
(provides employee efficiency data), knowledge management solution (provides
best practices to reduce Covid-19 risks data), and Google Trends (provides search
trends) as well as data from IoT devices and sensors - air quality sensors (provides
CO2 and humidity level data), camera sensors (provides data on whether
employees wear face masks and distancing data), 3D laser vision sensors (provides
people count in-room data) and manhole sensors for wastewater analysis;
• Outcoming data for actuator triggering and notifications for messaging services.</p>
      <p>The DROVIDS system calculates the risk levels based on the data received. As a
result, actuators are triggered, and notification messages are sent to employees
using messaging services.</p>
      <p>Several stakeholder groups are involved in DROVIDS business processes. Employees
accessing the DROVIDS platform can obtain information about the office's environment.
Shift seniors update the status of the disinfectant availability in the system. System
administrators administer the DROVIDS system - change system settings, manage sensors,
register and update employee information, etc. Facility administrators deliver wastewater
samples to the laboratory and upload the results to the DROVIDS system.</p>
      <p>A Level 2 diagram (see Figure 4) demonstrates how the DROVIDS platform is broken
into high-level containers (layers, building blocks, applications, and databases). The
frontend layer is designed for user interaction with the DROVIDS platform. Using the web
interface, company’s employees after the authentication and authorization process can
access the dashboard, where information about the office conditions is visible as well as
Covid-19 related search statistics retrieved from Google Trends. In addition to the
dashboard functionality, this front-end layer also provides other core functionalities like
device and classifier management functionality, National wastewater monitoring solution
results upload functionality, notifications for smart devices, enquiry possibilities with
room condition and restrictions statuses, and reporting (actual compliance status, actual
risk score, measures effectiveness score, flags about detected rules
breaches/incompliances, historical compliance overview, etc.).
The back-end layer is designed for data retrieval, processing, and decision-making to
estimate an infectious disease risk level, which in turn triggers actuators. A functional
decomposition is used there to separate back-end responsibilities:
1. Data retrieval service - The purpose of the component is to retrieve data from
external systems and IoT devices, and then store it in the database for further
processing. In the given design, external systems are integrated through the use of
a REST API, while IoT devices and sensors are integrated using either the LoRaWAN
network or REST API. The air quality sensors operate in the LoRaWAN network
using 868MHz frequency. Data from the camera and 3D laser vision sensors are
transferred to the DROVIDS platform using REST API. The management of sensors
in the LoRaWAN network is facilitated by the use of the open-source server
ChirpStack, which enables the administration of gateways, devices, tenants, and the
configuration of data integrations. Additionally, custom processing services are
being developed to incorporate other sensors that are not part of the LoRaWAN
network.
2. Data collection and risk prevention service - The component collects data for risk
level calculation and sends it to the Analytics service. Based on the response data
from the Analytics service, this component performs the relevant adjustment using
the actuator system or sends a notification. Given the wide range of actuator
systems available on the market, each with potentially unique integration options,
this service provides a REST API method for external actuator systems to access the
necessary data and trigger appropriate actions.
3. Analytics service - The component ensures the interpretation of the collected data
against risk assessment scores and threshold values. The component calculates risk
levels and relevant adjustments. This component also includes the implementation
of the Random Forest model to predict future IoT measurements. The technical
decomposition of the Analytics service is discussed below the Figure 4.
4. Risk adjustment service - The component's purpose is to analyse historical
adjustments and work process performance. Historical adjustments are the
decisions the DROVIDS platform makes based on collected real-time sensor data
and static data from external systems. This component analyses relationships
between historical adjustments and work process performance data and adapts
risk assessment scores and threshold values to trigger the adjustment. The service
intends to use Apache Spark for data analysis, implementing several models for
productivity calculation.
5. Notification service - The notification service provides notifications and inquiries
for the personnel. The DROVID platform's notifications are designed to be
displayed through the dashboard capabilities of the portal, which will be projected
onto TVs and monitors situated on the company's premises. Although e-mail or SMS
notifications may be considered in the future, such integrations are beyond the
scope of this design.
6. Additional building blocks - All other necessary building blocks required for the
solution's operation. These building blocks can be cache servers (e.g., Redis),
queuing mechanisms (e.g., RabbitMQ), libraries, etc.</p>
      <p>The data layer is designed to store various data - master data, configuration parameters,
sensor data, data from external systems, calculated adjustment data, etc. The APIs are
expected to be used to interact with data from external building blocks. The API interface
is intended to serve as both a REST API and a database API.</p>
      <p>The Analytics service is one of the key parts of the platform. Using machine learning
capabilities, this service evaluates the risk of infectious disease spread in the workplace
based on sensing data, providing real-time risk calculations and predictions. The
predictions are made to estimate the risk for scheduled events such as office meetings.
Figure 5 shows the technologies used to implement the analytical service, as well as data
ingest and feedback of data into enterprise information systems.
The DROVIDS platform receives live sensing and enterprise information systems data as
JSON messages (referred to as DTG_POST). The messages are handled using the Apache
Kafka messaging module. Depending on the request, the real-time risk is calculated or risk
predictions are obtained. If the predictions are requested, Apache SparkML is invoked. It
uses machine learning algorithms such as Random Forest to predict measurements of CO2,
humidity, pressure, temperature, and others. Since Random Forest is integrated in Apache
Spark MLlib, it allows to easily develop, train and integrate many models into a single
streaming application, thus allowing to predict each measurement with high accuracy. The
predicted measurements are passed to the risk calculation, which is also done in Apache
Spark Streaming. To evaluate the performance of the platform in terms of accuracy, the
predicted risk and measurements are saved in the Apache Cassandra database. The
accumulated data are used for off-line analytics and adjustment of the risk calculation
model. The calculated risk values are passed to the enterprise information systems
(referred as to DTG) and the messaging services for enactment of preventive measures.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusions</title>
      <p>The spread of Covid-19 infection in an organization can negatively impact its business
continuity. Not all organisations can perform work in remote mode; safe workspace is
essential to prevent virus spread across organisation employees, therefore reducing the
negative impact on society's health as well as the local and global economy. IoT technology
is widely used in healthcare care and building and facility management. It provides the
necessary capabilities to enable real-time based risk measurement and monitoring.</p>
      <p>The paper has presented the proposed solution for workspace safety, the DROVIDS
platform and its design models. The proposed solution provides predictive, preventive and
prescriptive capabilities to monitor and mitigate the risk of infections spread in the
enterprise.</p>
      <p>The given architecture of DROVIDS ensures the execution of several business processes
(data collection, processing, decision-making, and execution of actions). These different
business processes are decomposed at the level of services in this document. As a result,
the system is based on event-driven microservices and is modular, scalable, and
expandable in the future. The separate microservices approach, where each business
process is implemented in a separate microservice, allows receiving raw sensory data as
input using IoT devices and manhole sensors and further use the risk assessment model to
evaluate the COVID-19 risk in the company. The obtained data is further used to analyze
historical adjustments and work process performance and to determine future IoT
measurements using the Random Forest model.</p>
      <p>Besides the discussed C4 Level 1 and Level 2 diagrams that present the DROVIDS
design in a high-level logical manner, the C4 Level 3 diagrams, which showcase technology
and implementation details, have also been created. Additionally, the physical architecture
of the DROVIDS solution has been developed, enabling the transition to the solution
development phase. However, as these architecture diagrams contain highly detailed and
technical information, they are beyond the scope of this document. Currently, the DROVIDS
platform is in the development phase, with a focus on the Back-end layer services and the
necessary integrations discussed in this document.</p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgements</title>
      <p>Identification of Project “Platform for the Covid-19 safe work environment” (ID.
1.1.1.1/21/A/011) is founded by European Regional Development Fund specific objective
1.1.1 «Improve research and innovation capacity and the ability of Latvian research
institutions to attract external funding, by investing in human capital and infrastructure».
The project is co-financed by REACT-EU funding for mitigating the consequences of the
pandemic crisis.
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