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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Collaboration and Knowledge Networks: a Framework on Analyzing Evolution of University-industry Collaborative Innovation</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>School of Management and Economics, Beijing Institute of Technology</institution>
          ,
          <country country="CN">China</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>1817</year>
      </pub-date>
      <fpage>0000</fpage>
      <lpage>0002</lpage>
      <abstract>
        <p>Collaborations of universities and firms provide a key pathway for innovation. In recent years, interactions between the two communities have been reshaped with much higher complexity due to the enhanced ability of creating, disseminating and exchanging knowledge in big data era. This short paper aims to improve the framework of modeling interactions in UniversityIndustry collaboration by building both participant cooperation network and knowledge network for re-recognizing the patterns, characteristics and evolution trend of university-industry collaborative innovation. The proposed framework integrates techniques of bibliometrics, complex network analysis, and text mining to reveal the evolution of both participants interactions and their collaborative knowledge structure in a two-layers multiplex network. Network analytic metrics are selected to provide comprehensive insight on structural properties and characteristics. Finally, the industry of information and communications technology (ICT) is selected to provide an empirical case study to examine the feasibility of the framework.</p>
      </abstract>
      <kwd-group>
        <kwd>Collaborative Network</kwd>
        <kwd>Knowledge Network</kwd>
        <kwd>University-industry Collaboration</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>As an important part of innovation-driven development strategy,
UniversityIndustry Collaboration (UIC) is one of the most important ways of boosting
innovative capability of organizations, countries or higher-level collectives [1]. In recent
years, as the UI connections has been reshaped with much higher complexity due to
the enhanced ability of creating, disseminating and exchanging knowledge in big data
era, an increasing number of studies have examined the interactive mode of UIC from
a network perspective [2-4]. Under such circumstances, how to re-recognize the
patterns, characteristics and evolution trend in a new system of complex network is of
more theoretical and practical significance, for not only revealing the potential
cooperative opportunity, but also preparing the collaboration while planning the strategic
innovation.</p>
      <p>As a matter of fact, UIC innovations are doubly embedded in in social networks of
participants and knowledge networks constituted by coupling among knowledge
elements [5]. The nodes and links in both social networks of organizations and
knowledge networks not only reveal the ‘actor’ interactions but also explain the
processes and trend of knowledge interaction and absorption. Existing research has
provided promising analysis using research article co-authorship, patents co-application,
grants co-fund and research contracts cooperation to model the interactions of ‘actors’
in UIC via social network analysis [6]. However, comparatively less attention has
been paid in analyzing the content of these interactions, let alone profiling the
collaborative patterns in the dual-networks perspective of actors and content.</p>
      <p>This short paper aims to improve the framework of modeling UIC interactions by
building both collaboration networks and knowledge networks for future research in
mechanism and opportunity discovery. The proposed framework integrates techniques
of bibliometrics, complex network analysis, and text mining to reveal the evolution of
both UI cooperation and their knowledge transformation in a multiplex network.
Network metrics are selected to provide comprehensive insight on structural
properties and characteristics. Finally, the industry of Information and Communications
Technology (ICT) is selected to provide an empirical case study to examine the
feasibility of the framework.</p>
      <p>The rest of this paper is organized as follows: Section 2 reviews related work in
existing research. Section 3 describes the full process and modules of constructing the
framework. In Section 4, we present the findings observed in the empirical study
using ICT patents via the multiplex network analysis. The last section concludes this
study, explains the limitation and addresses future research directions.
2
2.1</p>
    </sec>
    <sec id="sec-2">
      <title>Literature review</title>
      <sec id="sec-2-1">
        <title>Collaborative and knowledge networks in UIC</title>
        <p>To understand and then promote scientific advances transformation into productive
forces, the research on scientific collaboration between universities and firms has long
been a joint focus, and become more active in big data era. Sonnenwald [7]
summarized scientific collaboration as interactions happening within a social context among
two or more individuals or higher collectives that facilitates the sharing of the
knowledge and accomplishing of tasks concerning a mutually shared superordinate
goal. In practice, both academia and industry can garner substantial benefits from
scientific collaborations. For universities, collaboration with firms can provide
opportunities to gain cutting edge insight by complementing their theory with practice [8,
9]; for industrial collaborators, it is beneficial to broaden knowledge scope by
contacting with universities and enhancing innovative capability [10].</p>
        <p>
          The scientific collaboration between UI are embedded in both in social networks of
organizations and knowledge networks established by coupling among collaborative
content [5]. Existing studies discuss the two networks in two separate strands. For
collaboration networks formed by participants, co-authorship/co-application network
analysis, have mainly been adopted to get a bird’s eye view of the structure of
collaboration and the status of authors/assignees for article and patent data [11, 12].
Comparatively, less attention has been paid to analyzing the content of these interactions
from a network perspect
          <xref ref-type="bibr" rid="ref19">ive. In year 2012</xref>
          , Phelps, Heidl and Wadhwa [13] refer to the
networks social relationships constitute in explaining the processes of knowledge
creation, diffusion, absorption and use as ‘knowledge networks’, and conducted a
systematic review and analysis of empirical research published on knowledge
networks. In recent years, an increasing number of empirical studies model knowledge
exchange in social relationships among collectives as knowledge networks [5, 13].
These knowledge networks are mainly built with co-application of international
patent classification codes [4, 5] and co-occurrence publication keywords [14] .
        </p>
        <p>Network perspective plays an important role in identifying patterns of
collaboration. The nodes and links in both social networks of organizations and knowledge
networks can present collaborative ‘actors’ and their interactions also knowledge
‘elements’ and their semantic relations. However, the two type of networks in existing
studies are analyzed in two separate strands in majority cases, providing only partial
view of the UIC, thus warrant further research.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Evolution of collaboration in research cooperation</title>
        <p>The position of items in a complex network structure determines its ability to absorb,
create, and transfer knowledge to a certain extent [15]. Based on complex networks,
Newman [16] and Barrat, Barthélemy and Vespignani [17] applied the average
shortest distance of the network, degree distribution, aggregation degree and other
indicators to measure the structural characteristics of collaboration network, and studied the
statistics of complex networks. With the assistance of these indicators, structure
properties of networks can be revealed. Furthermore, an increasing number of studies
described the temporal and spatial evolution of cooperative networks using
streaminglike datasets. Fischer, Schaeffer and Vonortas [2] selected the twelve most eminent
universities in Brazil for the years 1994, 2004 and 2014 and explored the evolution of
patenting activity and linkages to industry via co-assignee network. Kim, Lee, Choe
and Seo [18] applied node degree, network density, and centrality indicators to
describe the structure and evolution characteristics of the cooperation network between
the main clusters of the software industry.</p>
        <p>However, existing UIC research mainly focused on depicting the structural
properties of participants’ collaborative networks (i.e., individuals, teams and institutions),
or spatial networks (cities and countries). The evolution of knowledge networks in
UIC context was seldom studied jointly. The evolution analysis of collaboration
networks and knowledge networks was discussed the in two separate strands as well.
3
3.1</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <sec id="sec-3-1">
        <title>Collaboration and knowledge networks construction</title>
        <p>The challenge of analyzing both collaborative and knowledge interactions in UIC
requires combining design and methods from social and knowledge network analysis.
In this research, we apply patents data from frequently used Derwent Innovation
Index database (DII) to construct collaboration and knowledge networks. The
datapreprocessing assumptions and modules can also be applied to scientific articles data
from Web of Science (WoS) databases and so forth. We first pre-process the assignee
organization field in patents, with assumptions for Natural Language Processing
(NLP) and data categorization purposes. Universities and industrial organizations are
recognized and tagged based on these definitions.</p>
        <p>Assumption 1: industrial organizations are those were built on the theory of the
firm, or public enterprises, or non-profit organizations, which provide products or
services to the society. Universities and higher education providers are academic
organizations. We also include research institutions and academic research laboratories,
which dedicated to education and scientific research to this category.</p>
        <p>Assumption 2: We tag assignee organizations in patents with terms indicating
academic feature as university-side organizations: for example, “University”,
“Institution”, “School”, “College”, “Faculty” and so forth. Meanwhile, all organizations are
given an industrial tag if their names containing “Ltd” (Limited), “Co.” (Company),
and so on.</p>
        <p>This study constructs a multiplex network consisting of two layers: organization
layer   (  ,  ) and knowledge layer   (     ,  ). For the organization
layer, we set tagged organizations as nodes and drew their collaboration relations as
links. For knowledge network, it has four-digits international patent classification
codes (IPC) defined by the World Intellectual Property Organization (WIPO) as
vertices and their co-occurrence relations as ties to quantitatively measuring semantic
structure. The IPC code is one of the most straightforward proxies considering the
availability of data and has been set as knowledge ‘elements’ in existing research of
network construction [5]. Modeling the multiplex networks in annual patent datasets,
we can then track the evolution of UIC in the target area, and further analyze future
trends based on the historical evolution of the networks. Fig. 1 shows the framework
of UIC multiplex network.
possible connections with the same number of nodes [20], as shown in equation (1).
network structure.
equation (2)[16].</p>
        <p>in which  denotes the actual connections, and   
stands for all the potential
connections.   
=  (</p>
        <p>− 1) ∕ 2,  is the total number of vertices in the target
network. Smaller network density indicates looser connections between the elements,
which implies the behaviors of network elements will receive less influence from the</p>
        <p>Global clustering coefficient is calculated based on local clustering coefficient of
each node, measuring the clusters of the whole network, which can be computed via
 =</p>
        <p>= ∑  

(1)
(2)
(3)
vertex  .</p>
        <p>in which   stands for local clustering coefficient, and   = 2  ⁄  (  − 1). Here
  represents the number of edges for vertex  , and  
indicates the degree value of</p>
        <p>In this study, we applied the metric of average path length to distinguish negotiable
networks from comparatively inefficient ones. The average path length  is calculated
as the average length of the shortest path between any two nodes, which can be
computed via equation (3).</p>
        <p>2
 =</p>
        <p>( −1) ∑ ≠  
in which the distance   between node  and node  depicts the total number of
links connecting the shortest path of the two nodes, and where  represents the total
number of nodes in the network.
4
4.1</p>
      </sec>
      <sec id="sec-3-2">
        <title>Data</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Empirical case study: evolution analysis of UIC in ICT area</title>
      <p>We select Information and Communications Technology (ICT) field as the target area
to conduct an empirical case study in this section. ICT has become an extensional
description that covers information technology and communications, and its concept
keeps evolving and broadening in recent years. It can be applied in different domains
with wide-ranging innovative and socio-economic impacts across various parts of the
economy, thus attracts continuous research attention from both academic and
industrial communities [21, 22]. This paper followed the definition on ICT industry in
OECD compendium of patent statistics, retrieved 25,749 U-I collaborative ICT
patents with China as assignee country from the Derwent Innovation Index database
(DII), during the time period of 2006-20171. We pre-processed the dataset followed
the assumptions in Section 3 and tagged all universities (academic organizations) and
firms.</p>
      <p>
        Based on the first time an invention is collected in DII, Fig. 2 presents the annual
number of patents in each year from 2006 to 2017, and also shows the corresponding
numbers of universities and firms engaged in UI collaborations every year. The
general trend of patent grant of Chinese ICT industry is growing continuously, which
confirms fast growing research and development interests of ICT in recent years. Both
participant universities and industrial organizations are growing steadily. The growth
trend of academic collaborators is more flatten, while the rising tendency of
participating firms rece
        <xref ref-type="bibr" rid="ref19">ived marked rise from year 2012</xref>
        to 2017, which basically fit the
general trend of patents growth.
We constructed two layers of the UIC multiplex network to model the collaboration
and knowledge interactions for ICT area. For the organization layer, nodes were
tagged organizations, while ties were set as their collaboration relations. For
1
      </p>
      <p>We define U-I collaborative patents as patent that have both universities and firms as
assignees. The field of timespan setting we applied for patent retrieval is Basic Patent Year,
which is the first time an invention is collected in the DII.
knowledge network, vertices were four-digits IPC codes and links were their
cooccurrence relations. As one of the most straightforward proxies of technological
knowledge considering the availability of data, IPC nodes provided concise
description of knowledge elements in ICT. Further semantic analytics can be conducted
using patent abstracts or claims with scientific text mining techniques, we will discuss
the possible improvement for knowledge element extraction in the discussion,
research limitations and future work.</p>
      <p>Although patents are not typical dynamic data in the narrower sense. Patents are
granted on a continual basis. Two-layers multiplex networks based on annual patent
data were constructed to present the historical evolution of UIC in ICT. Fig. 3
presented the collaboration layer of multiplex networks in year 2006 and year 2017, in
which all the academic organizations were marked in yellow and all the industrial
organization were highlighted in purple.</p>
      <p>
        We can observe from Fig. 3 subfigure (a) that in year 2006, there were only limited
number of ICT organizations collaborative clusters. Majority of the core organizations
were universities rather than firms, for example, Peking University (UYPK-C),
University of Shanghai Jiaotong (USJT-C) and Tsinghua University (UYQI-C). At this
stage, the technological collaboration of ICT was mainly leading by academic
organization. The only firms stood out in year 2006 was Huawei Technologie
        <xref ref-type="bibr" rid="ref1">s Co Ltd
(HUAW-C). In year 2017</xref>
        , both the participants and their connections, or we say
nodes and ties, of the of UIC have received marked rise. As shown in Fig. 3 subfigure
(b), as a leading firm, State Grid Corporation of China (SGCC-C) became the most
significant node in the collaborative network. Although universities like Tsinghua
University (UYQI-C) still served as the central role on the edge of the network, an
increasing number of firms started to take the core position in the clusters.
      </p>
      <p>From year 2006 to 2017, the size of corresponding knowledge network grew
substantially. Fig. 4 selected and presented knowledge networks of UIC in ICT industry
in year 2006 and year 2017. The clusters in Fig. 4 subfigure (a) showed the ICT main
topics in year 2006, which had G01N (Investigating or analyzing materials by
determining their chemical or physical properties), G06F (Electric digital data processing),
H04L (Transmission of digital information), H04N (Pictorial communication) and
H01L (Semiconductor devices; electric solid-state devices not otherwise provided for)
as core knowledge elements.</p>
      <p>In year 2017, the network has evolved with much higher density with more
complex characteristics. As shown in Fig. 4 subfigure (b), the topic related to G01N
(Investigating or analyzing materials by determining their chemical or physical
properties) drew away from other main clusters. The size of H01L (Semiconductor devices;
electric solid-state devices not otherwise provided for) and related codes did not grow
observably, implying that this is not the main effort of UIC in China. On the other
hand, the communities of G06F (Electric digital data processing) and H04L
(Transmission of digital information) grew markedly during the 12 years, which fit the
technological advance under the impact of digitalization. In addition, a new cluster of
knowledge interaction was developed in ICT, which led by G01R (Measuring electric
variables; measuring magnetic variables).
4.3</p>
      <sec id="sec-4-1">
        <title>UIC Multiplex network evolution analysis</title>
        <p>After multiplex networks construction, we proceeded network analysis on annual
patent data to illustrate the change of network cluster characteristics and negotiability
in the process of the multiplex network evolution. The number of total nodes, featured
nodes and edges are computed first to interpret topological properties of the multiplex
networks. We then calculated the network density, clustering coefficient and average
path length to reveal cluster characteristics and negotiability of UIC interaction
system in ICT area. Table 1 and Table 2 listed all the calculated structural characteristics
in the two-layers multiplex network evolution.</p>
        <p>
          We illustrated the topological features of the multiplex network in Fig. 5. For the
collaboration network layer, as shown in Fig.5 subfigure (a), the number of
participating firms rose more sharply than the number of universities; the connections of the
two commun
          <xref ref-type="bibr" rid="ref19">ities grew dramatically since 2012</xref>
          . This trend indicated that industrial
organizations in China started to actively part
          <xref ref-type="bibr" rid="ref12">icipate UIC after year 2011</xref>
          . For the
knowledge network, as shown in Fig.5 subfigure (b), the number of nodes gradually
increasing during the 12 years, showing the ICT related technologies steadily expand
with the assistance of UIC, while the interactions of these knowledge elements
became increasingly frequent while the knowledge was expanding.
2 Clustering Coefficient
3 Average Path Length
        </p>
        <p>Network density describes the connectivity of a network, in which a smaller
density value indicates the behaviors of network elements will receive less influence from
the network structure. The global clustering coefficient measures the tendency of
vertices to cluster together. Fig.6 depicted the evolution trend of network density and
clustering coefficient to measure the cluster characteristics based on the normalized
valued provided in Table 1 and Table 2. The network density trend of both
collaboration networks (marked in light blue) and knowledge network (marked in light green)
decreased by years, indicating connections between both collaboration participants
and knowledge elements they have created were becoming looser. The trend
clustering coefficients of collaboration networks also steady decreased, while the knowledge
networks had an opposite tendency. After year 2015, the existence of groups of nodes
in the knowledge network were more densely connected.</p>
        <p>The evolution of cluster characteristics of the multiplex networks illustrated that
the cooperative innovation between enterprises and academic research institutions
was getting easier and wider, thus the scale of UIC was markedly broadened. There
were more potential collaborators to choose recently than before. However, for
knowledge network, some of the elements started to show agglomeration advantages
in gathering scientific and technological knowledge from 2015. The network had
scattered and scaled agglomeration features.</p>
        <p>
          We finally examined the negotiability of the UIC multiplex network for ICT
industry. Fig.7 presented the evolution trend of how negotiable of the network in two
dimensions of partner collaboration and knowledge generation, based on the normalized
average path length provided in Table 1 and Table 2. As illustrated via blue curve,
the collaboration network of Chinese ICT area has beco
          <xref ref-type="bibr" rid="ref7">me more negotiable from year
2011</xref>
          . There were less cost any two nodes needed to pay when building a connection
since then. The negotiability of the knowledge work increased steadily. The network
became much more efficient than before, however, the information could not reach as
far as before, which implied the research and development in this area was pushed to
a more refining level.
ICT-related technologies are pervasive nowadays. This empirical study illustrates that
the UIC activities is characterized with sharp growth and high level of pervasiveness.
There were considerable entry of new universities and firms for ICT area from year
2006 to 2017. The multiplex network we constructed contains heterogeneous
information, and the evolution of collaboration and knowledge network layers presented
different cluster characteristics and negotiability. With 12 years development, now it
is more convenient for both universities and firms to build a connection in this area.
However, the knowledge network started to show rich-club phenomenon a certain
extent. Some of the knowledge elements had more agglomeration advantages than
others, which will have potential influence on future collaboration activities.
        </p>
        <p>This empirical study applied 4-digits IPC codes as straightforward proxies of
technological knowledge considering the availability of data. Although IPC nodes can
provide concise description of knowledge elements in ICT, they are not able to reveal
the detailed topics and semantics of the target area. Further semantic analytics can be
conducted using patent abstracts or claims with scientific text mining techniques. In
other words, the knowledge layer of the multiplex network can be replaced with a
more precise version to illustrate the detailed content of research and application
topics.
5</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusion, limitation and future work</title>
      <p>In this short research paper, we explored a new perspective of modeling UIC
interactions by building both collaboration networks and knowledge networks for future
research in mechanism and opportunity discovery. Although this paper provides
heuristic research on summarizing existence of collaboration network and knowledge
network in UIC in to a multiplex framework, it has several limitations that need be
explored in future research: (1) the knowledge elements we applied are four-digits
IPC codes, which provided concise proxies of technological concepts, however, these
tags are not able to present the actual content and semantics of patents; (2) this paper
did not dig deeply into the dynamic mechanism of how interactions in collaboration
network drive the knowledge creation and exchange in knowledge network; (3) only
limited network structure indices were applied when profiling the dual-networks
evolution.</p>
      <p>From the perspective of scientific text mining, both IPC codes and keywords listed
by authors or applicants are just proxies of ‘knowledge element’. Exiting research
have not reached an agreement on whether these proxies are sufficient or how to
extract more informative ‘elements’ to model the content of the target corpus. We will
address this issue in our future research, to keep improving performance of the
multiplex network in representing and analyzing the complex system of UIC.</p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgements References</title>
      <p>This work was supported by the National Natural Science Foundation of China (Grant
No. 72004009).
4.</p>
    </sec>
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