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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Unveiling technology clusters and prominent investors of home automation networking through patent analysis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Konstantinos Charmanas</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Konstantinos Georgiou</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nikolaos Mittas</string-name>
          <email>nmittas@chem.ihu.gr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lefteris Angelis</string-name>
          <email>lef@csd.auth.gr</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Chemistry, International Hellenic University</institution>
          ,
          <addr-line>65404 Kavala</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Informatics, Aristotle University of Thessaloniki</institution>
          ,
          <addr-line>54124 Thessaloniki</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Home automation systems and networks aim to boost the quality of life and support the automation of industrial operations. Their wide applicability has attracted the interest of researchers and companies. In the last decades, home automation systems constitute an emerging domain, and the corresponding developed technologies are available to both organizations and infrastructures as well as common users. The importance of home automation systems is apparent as their technologies are utilized in various important domains such as smart homes, Internet of Things (IOT), vehicles and healthcare. Companies that develop products of this nature aim to patent their most valuable technologies in order to protect their investments against rival competitors. The granted patents are recorded and stored by different patent offices that provide comprehensive information and constitute the knowledge base in much research. In this study, we analyze patent records from the United States Patent and Trademark Office (USPTO) that are related to home automation networks in order to reveal the most relevant technologies and domains of application as well as the respective prominent stakeholders. Our findings provide insights on the current state of home automation technologies and support researchers and organization in tasks that are related to competitor analysis, strategic planning and technology forecasting.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Patent analysis</kwd>
        <kwd>Home automation networks</kwd>
        <kwd>Cluster analysis</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Ubiquitous computing is a concept that
encompasses multiple different areas of the
computer science domain, including distributed
computing, sensors and IoT technologies as
well as artificial intelligence. A primary aspect
of ubiquitous computing is its objective on
affecting the daily aspects of human life,
providing time-saving and innovative
alternatives to otherwise tiring tasks. An
example of ubiquitous computing that
highlights its presence in the modern society are
home automation systems, expressed in devices
that range from digital assistants to smart
lightbulbs and devices that can be found in an
average household.</p>
      <p>
        The importance and benefits of home
automation systems are more than evident in
everyday activities, as they provide capabilities
that facilitate and improve home security,
management, flexibility and remote control.
The main components that encompass a
complete home automation system are the user
interface, the participating electronical devices
and a mode of transmission [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. The additional
components of common home automation
systems include voice recognition, mobile
communication through messaging and IOT, as
well as popular Information and
Communication Technologies (ICTs) like
Bluetooth and Wi-Fi [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Such a plethora of
applied concepts indicates that the different
home automation technologies should be
evaluated based on indicators that measure both
their capabilities and potential costs, which
include data rates, transmission range, energy
costs, security, complexity and more [
        <xref ref-type="bibr" rid="ref3 ref4">3,4</xref>
        ].
Hence, creating and establishing home
automation systems that can effectively exploit
these indicators through efficient technologies
and inventions consists of a challenging task.
      </p>
      <p>
        Given that inventions with innovative
concepts of home automation technologies
provide organizations and companies with
ample opportunities of exploiting them in the
market, the early patenting of inventions has
become a staple for investors of not only home
automation, but also in any other technological
domain. Thus, patent data can be a potent
indicator of technological growth, development
and business activity [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>In this study, we explore the main
applications and technologies that are related to
home automation systems through a patent
analysis methodology that employs
dimensionality reduction and cluster analysis
techniques. To do so, we collect and analyze
information of technological patents, derived
from the USPTO, that are related to home
automation systems. Complementary, we also
reveal the main stakeholders that invest in home
automation technologies and contribute to the
landscape profiling of the investigated
technological area and subareas.</p>
      <p>The results of this study provide insights for
both practitioners and industries in identifying
the main domains, applications, methodologies
and competitors of home automation
technologies. In the context of disseminating
knowledge, this study serves as a steppingstone
in merging the disciplines of ubiquitous
computing and patent analysis, offering
valuable information that can foster and
promote additional research on the topic. In
addition, our methodologies constitute a robust
example of applied Machine Learning on
ubiquitous computing data, indicating
breakthrough findings related to patents of the
field via a streamlined data analytics pipeline.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <p>
        Patent analysis is a process that is related to
analyzing information of patent data and
2
https://www.uspto.gov/web/patents/classification/cpc/html/cpc.h
tml
extracting knowledge for various purposes
including trending analysis, technology
forecasting, strategic positioning and
competitor analysis [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. The main properties of
patent data provide information regarding the
patent assignees (companies or organizations)
and inventors, textual descriptions of the patent
claims as well as citation relations with other
patents, literature and applications. Also, each
patent is assigned to one or more classes that
characterize its technological objectives, using
some popular classification schemes such as the
Cooperative Patent Classification (CPC)2 and
International Patent Classification (IPC)3
schemes.
      </p>
      <p>
        Patent analysis is a well-known technique
that has application in different technological
domains that are related to augmented reality
[
        <xref ref-type="bibr" rid="ref6 ref7">6,7</xref>
        ], IOT [
        <xref ref-type="bibr" rid="ref8 ref9">8,9</xref>
        ], healthcare [
        <xref ref-type="bibr" rid="ref10 ref11">10,11</xref>
        ] and vehicles
[
        <xref ref-type="bibr" rid="ref12 ref13">12,13</xref>
        ] among many others. In general, the
various employed methodologies and data
mining techniques applied in patent analysis are
usually based on citation networks [
        <xref ref-type="bibr" rid="ref14 ref15 ref16">14,15,16</xref>
        ],
topic modelling [
        <xref ref-type="bibr" rid="ref17 ref18 ref6 ref7">6,7,17,18</xref>
        ], co-word analysis
[
        <xref ref-type="bibr" rid="ref19 ref20">19,20</xref>
        ], deep learning [
        <xref ref-type="bibr" rid="ref21 ref9">9,21</xref>
        ] and clustering
algorithms [
        <xref ref-type="bibr" rid="ref22 ref23 ref9">9,22,23</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Methodology</title>
      <p>The first goal of this study is to discover the
general technological areas where home
automation networks are applied and the
methodologies that are leveraged to construct
this type of networks. The second goal is to map
the main assignees of technological patents,
that are related to home automation networks,
and identify the main stakeholders of each
technological area, as measured by the overall
patents that they possess. These two goals are
summarized into the following Research
Questions (RQs):</p>
      <p>RQ1: What are the main technological areas
that are related to home automation networking
technologies?</p>
      <p>RQ2: Who are the main stakeholders of the
different technologies that are related to home
automation networking?</p>
      <p>The main framework of this study is
presented in Figure 1.
3 https://www.wipo.int/classifications/ipc/en/</p>
      <p>Data
Collection</p>
      <p>K-means</p>
      <p>RQ2
PCM</p>
      <p>PCA
Main
Stakeholders</p>
      <p>RQ1</p>
      <p>Granted Patents
800
600
400
200
0</p>
      <p>
        In order to discover the general areas of the
investigated domain, we employ a
methodology similar to [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] by clustering the
collected patents based on their CPC subgroup
ID assignments. Our choice in replicating this
methodology stems from the fact that the results
of [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] are promising and well structured,
rendering this study as a leading baseline in
patent analysis.
      </p>
      <p>In this approach the first step is to construct
the Patent CPC Matrix (PCM) as follows (1).
1, when  ℎ  −  ℎ
(1)


=</p>
      <p>ℎ  −  ℎ</p>
      <p>{ 0,
 

 ℎ
where i=1,2,…,N and j=1,2,…,M. N is
equal to the number of the collected patents,
5740 in our case, and M is equal to the number
of the distinct CPC subgroup IDs assigned to
the collected patents (5523 overall).</p>
      <p>
        In the next step, since the number of CPC
subgroups is quite extensive, we apply the
Principal Components Analysis – PCA [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ]
dimensionality reduction technique that helps
in boosting the performance of the clustering
analysis for high dimensional data [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ].
      </p>
      <sec id="sec-3-1">
        <title>Moreover, we employ the</title>
        <p>
          K-means
clustering algorithm [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ] to discover the main
technological areas, expressed as groups of
CPC subgroups, that are related to home
automation networking. The selection of
Kmeans was based on its wide application in
similar patent analysis studies and
on its
interpretability. In this approach each patent is
assigned to a single cluster based
on its
properties derived from the PCA technique. In
order to pick the optimal number of clusters for
our analysis we make use of two evaluation
metrics: (i) the silhouette coefficient [
          <xref ref-type="bibr" rid="ref28">28</xref>
          ] and
The
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>Normalized Pointwise Mutual</title>
      </sec>
      <sec id="sec-3-3">
        <title>Information –</title>
        <p>
          NPMI [
          <xref ref-type="bibr" rid="ref29">29</xref>
          ].
        </p>
        <p>The silhouette
coefficient of a single data point is presented in
(ii)
(2)
s(i) =</p>
        <p>( )− ( )
max ( ( ), ( ))
where  ( ) is the mean distance between the
i-th data point and the points that belong to the
same cluster while  ( ) denotes the minimum
mean distance between the i-th data point and
the points of the remaining clusters.</p>
        <p>While the silhouette coefficient is a standard
approach to evaluate clustering models, the
NPMI will help us to interpret the extracted
clusters in terms of general technological areas
using the five most probable CPC subgroup IDs
of each cluster. The NPMI between two features
is presented in (3).
(2)
(3)
where  ( ) denotes the probability of a
patent being assigned to the i-th CPC subgroup
identifier and  ( ,  ) denotes the probability of
a patent being assigned to both i-th and j-th</p>
      </sec>
      <sec id="sec-3-4">
        <title>CPC subgroup identifier.</title>
        <p>Finally, we make use of the information
related to the assignees of each patent, included
in
the
patent
data, to
reveal the
main
stakeholders of each technological area. In this
phase, we rank the linkage strength of an
assignee and a cluster according to the number
of patents and belonging to this cluster and
under the ownership of this assignee (Main
Stakeholders).</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Results</title>
      <p>4.1.</p>
      <p>RQ1:</p>
      <p>What
are
the
main
technological areas that are related
to
home
automation
networking
technologies?</p>
      <p>By
leveraging
the
patent
properties
extracted from the PCA, we conduct several
experiments to choose the number of clusters
that optimize the NPMI and the silhouette
coefficient. In this study, we set the range
clusters from 2 to 20. The evaluation of the
extracted models is presented in Figure 3.</p>
      <p>10No_Clusters
5
15
20
of the collected patents belong to the tenth
cluster that represents the general area of home
automation networks as multiple patents are
assigned only to the CPC subgroups that are
related to the prefixes of Table 1. By inspecting
the most probable CPC subgroups, we can
conclude that the results do not indicate
significant overlaps between clusters apart from
some cases where the subgroups of the last
cluster occur in other clusters as well. As the
last cluster is related to the general investigated
technological area, the identified overlaps
should be characterized as insignificant and
expected.</p>
      <p>This observation shows that the applied
approach discovered distinct and interpretable
technological areas. These areas are related to
both interesting and established techniques
applied on home automation networks e.g.,
Error detection and Information Security,
Information retrieval and transferring and
important domains that leverage technologies
of home automation networks e.g., healthcare,
vehicles, Storage and control devices, air
screening, games.</p>
    </sec>
    <sec id="sec-5">
      <title>4.2. RQ2: Who are the main stakeholders of the different technologies that are related to home automation networking?</title>
      <p>In this subsection we present the main
assignees contained in the retrieved patents.
The involvement of the investigated assignees
reveals their overall interest in the
technological area of home automation
networks. This involvement can be translated
on investments in patent technologies, their
desire for applications of these technologies
and the strategic advantages or disadvantages
against competitors in the technological area of
home automation networks. In brief, a total of
922 assignees are detected in the retrieved
patent data with more than 50% percent owning
a single patent, while the assignees’ mean
number of granted patents is less than 7 and the
largest number of granted patents is 422, owned
by Samsung. This statistic indicates that the
majority of assignees are not investing in many
home automation network patents, being
overrun by competitive technological giants,
while there is also a small proportion of
assignees that invest frequently in technologies
that are related to home automation networks,
while having the resources and market shares to
do so.</p>
      <p>By combining the information of the patent
data with the technology clusters that were
extracted in the previous subsection, we are
able to distinguish the main of assignees of each
cluster. The top three most involved assignees
of each technology cluster are presented in
Table .</p>
      <p>Table 2
Main assignees of the technology clusters</p>
      <p>Top assignees per cluster
STATE FARM MUTUAL AUTOMOBILE
INSURANCE COMPANY ; 16Lab Inc ;</p>
      <p>2Wire, Inc. (Cluster 1)
WINT WI Ltd ; 16Lab Inc ; 2Wire, Inc.</p>
      <p>(Cluster 2)
May Patents Ltd. ; 16Lab Inc ; 2Wire,</p>
      <p>Inc. (Cluster 3)
Cisco Technology, Inc. ; 16Lab Inc ;</p>
      <p>2Wire, Inc. (Cluster 4)</p>
      <p>University of Florida Research
Foundation, Inc. ; Delos Living LLC ;</p>
      <p>16Lab Inc (Cluster 5)
Microsoft Technology Licensing, LLC
; Canon Kabushiki Kaisha ; Hitachi,</p>
      <p>Ltd. (Cluster 6)
Intel Corporation ; 16Lab Inc ; 2Wire,</p>
      <p>Inc. (Cluster 7)
Broadcom Corporation ; 16Lab Inc ;</p>
      <p>2Wire, Inc. (Cluster 8)
Google Inc. ; 16Lab Inc ; 2Wire, Inc.</p>
      <p>(Cluster 9)
Samsung Electronics Co., Ltd. ; Sony</p>
      <p>Corporation ; Google Inc. (Cluster</p>
      <p>10)</p>
      <p>By inspecting the results presented on the
table above, we detect that 16Lab Inc and
2Wire, Inc. are involved in the majority of the
extracted technology clusters. 2Wire, Inc.4 was
a home networking equipment manufacturer
that provided products to telecommunication
companies while 16Lab Inc5 provides an
integrated platform for IOT and wearable
developers. While these two assignees are
strongly related to home automation networks,
we also observe some established software and
hardware companies, that do not only invest in
home automation networks but lead pioneering
developments in other fields as well, like
Google, Samsung, Sony, Microsoft and Cisco.</p>
      <p>Among the different areas of interest of the
assignees, we can distinguish that farming,
automobiles, information security, IOT,
hardware, software development, healthcare
and telecommunications are the most frequent
ones. These observations reveal that home
automation networks are useful in many
technological areas, systems, devices and
applications.</p>
    </sec>
    <sec id="sec-6">
      <title>5. Conclusions and Future Work</title>
      <p>In this study, we presented and uncovered
the main technological areas and assignees that
are related to home automation networking by
analyzing patent data derived from the USPTO.
The first step in our approach was to investigate
the patent objectives using the CPC
assignments that characterize them. Next, by
applying a dimensionality reduction technique
and a clustering algorithm, we succeeded in
identifying and interpreting the main
technology clusters of home automation
network patents, providing effective answers to
RQ1.</p>
      <p>Moreover, the information regarding the
assignees of each patent and the technology
clusters extracted from the K-means algorithm
help us in identifying the main stakeholders of
the different technologies that are related to
home automation networks (RQ2).</p>
      <p>Our approach unveils some interesting
technological areas that are related to home
automation networking which support the
utilities of farming, healthcare, automobile,
security and information systems. Furthermore,
the applied methodology reveals the main
investors in each domain that applies home
networking technologies and their interest in
patent granting.</p>
      <p>The challenges that arise from the
combination of ubiquitous computing in
machine learning stem from the proper
understanding of the field and its usage on daily
life as well as the identification of proper
datasets for analysis. Nevertheless, we believe
that our insights prove that such challenges can
be overcome when studying ubiquitous
computing from an industrial perspective.</p>
      <p>By recapping, we believe that the proposed
approach provides valuable information that
could be useful for companies and individuals
in scoping the main competitors and potential
collaborators in future projects. We expect that
this information can also provide guidelines to
practitioners and researchers in identifying
important technologies and methodologies in
the general domain of home automation
4 https://en.wikipedia.org/wiki/2Wire
5 https://16lab.net/about/
networking, which could be a great asset in
future studies and in the forging of new
inventions and applications. As far as the
development and knowledge sharing on
ubiquitous computing is concerned, this study
is a great example of interdisciplinary research
that promotes complementarity in science, a
concept that should be leveraged by other
researchers.</p>
      <p>Also, we believe that the proposed
methodology can provide effective results not
only on patent data but also on research
literature data. For instance, the CPC subgroup
identifiers in the clustering approach could be
replaced with the keywords of each study while
the patent assignees could be replaced with the
authors and publication venues of the studies.
In general, this approach can be used to identify
the main individuals or contributors of a dataset
and further discover the main areas or topics of
that are reflected on the dataset records.</p>
      <p>Evidently, there were some limitations in
our study. Firstly, the data that were used for
this study are derived exclusively from the
USPTO and not from all the available patent
offices. Additional data from the various related
industries and patent offices should be
evaluated in order to generalize the results of
this study. Despite the occurrence of these
limitations, USPTO is characterized as a
reliable source for patent analysis that reflects
on the industrial technologies and interests.</p>
      <p>Furthermore, additional experiments should
be conducted in order to verify our approach as
an effective alternative for general tasks and
different data. Some important stages regarding
the evaluation and interpretation of the clusters
were conducted in a manual fashion. As a
result, we believe that several alternatives in
different stages of this approach should also be
investigated. Despite the existence of the issues
described previously, the algorithms and
evaluation metrics of the proposed approach are
similar to multiple existing studies that provide
satisfying methodologies and outcomes.</p>
      <p>Nonetheless, we consider that future studies
could also explore the general domain of home
automation networks through additional
information and purposes. The patent titles and
abstracts are two very important features that
describe the nature of the inventions and could
possibly be analyzed for knowledge discovery
through topic modelling or co-word analysis.
Also, the patent granting dates, filing dates and
inventors are features that are included in the
patent data and provide useful information
about the overall temporal growth of a
technological domain and the most prolific
individual inventors respectively. Finally, we
believe that the citation properties of the patents
contain valuable information regarding the
technological value and influence of the patents
that help in identifying emerging and dominant
technologies and determining the strategic
positioning of assignees.</p>
    </sec>
    <sec id="sec-7">
      <title>6. References</title>
    </sec>
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