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Examining
he
dynamics
o
an
eme ging
esea ch
ne wo k
using
he
case
o
iboelec ic nanogene a o s
Suominen
A ho,
Peng
Haoshu,
Ranaei
Sami a
Suominen,
A.,
Peng,
H.,
Ranaei,
S.
(2018).
Examining
he
dynamics
o
an
eme ging
esea ch
ne wo k using he case o iboelec ic nanogene a o s. Technological Fo ecas ing and Social
Change. DOI: 10.1016/j. ech o e.2018.10.008
Final d a
Else ie
Technological
Fo ecas ing
and
Social
Change
10.1016/j. ech o e.2018.10.008
© 2018 Else ie Inc.
Examining he dynamics o an eme ging esea ch ne wo k using he
case o iboelec ic nanogene a o s
A ho Suominen
, Haoshu Peng, Sami a Ranaei
A B S T R A C T
The analysis o a scien is 's decision o conduc esea ch in a speci
fi
c scien i
fi
c
fi
eld is an in e es ing way o ace he
eme gence o a new echnology. The g ow h o a esea ch communi y in size and pe sis ence is an impo an
indica o o a new scien i
fi
c
fi
eld's i ali y. Using a case s udy on iboelec ic nanogene a o (TENG) echnology,
his s udy iden i
fi
es how esea ch pa icipa ion and communi y dynamics e ol e du ing he eme gence phase o a
echnology, and u he wha a e he key condi ions and de e minan s o he eme gen au ho ne wo k. The s udy
uses scien i
fi
c publica ion da a om 2012 h ough 2017 ex ac ed om he Web o Science da abase. Resul s
show communi ies eme ging h ough ac o s' close p oximi y a he han om hei sha ed hema ic o ien a ion.
Fo indi idual esea che s, he bounda y be ween p io esea ch and TENG esea ch was negligible pa ly
ques ioning he exis ence Kuhnian pa adigm shi s.
1.
In oduc ion
Eme gence is wha a
“
sel -o ganizing p ocess p oduces
”
(Co ning,
2002). Sel -o ganiza ion equi es ac o s, o ganiza ions and indi iduals
ha will ake pa in he p ocess o eme gence. In he con ex o ech-
nological eme gence, he dynamics o ac o s aking a ole in he dis-
co e y p ocess ha e been b oadly analyzed. Resea che s ha e s udied
he eme gence o esea ch ne wo ks h ough co-au ho ship (Suominen,
2014), co-ci a ion (Boyack and Kla ans, 2010), and bibliog aphical
coupling (Ja ne ing, 2007). Resea che s ha e used o he s s udies o
examine whe he au ho s sha e e minology and c ea e pe sis en new
esea ch opics ha migh be eme ging (Guo e al., 2011; Small e al.,
2014; Suominen and Toi anen, 2015). In p ac ice, an ac o 's ole has
been ope a ionalized h ough p oxies such as he a e age numbe o
au ho s pe pape , he numbe o con ibu ing o ganiza ions, and he
numbe o coun ies o ci ies in which he au ho s conduc esea ch.
In 1969, Ay es (1969) pu o wa d a amewo k o he sel -o ga-
nizing dynamic p ocess o ac o s. This p ocess was based on he numbe
o ac o s being a unc ion o an al eady known and in e es ing idea le
wi hin a
fi
eld. Ay es ollowed a Humbold ian no ion ha he p og es-
sion o echnology and selec ion o esea ch opics a e he unc ion o
he a ailabili y o no el ideas. Ay es d ew om Hol on (1962), who
s a ed ha only a
fi
ni e lode o in e es ing ideas exis s wi hin a scien-
i
fi
c
fi
eld. Once a scien is opens a new lode ia a scien i
fi
c disco e y,
mo e in es iga o s mig a e o he new
fi
eld. This phenomenon is called
a
‘
gold ush
’
as schola s
“
de ec om hei old
fi
eld, in sea ch o
g eene pas u e
”
(Ay es, 1969). As he mine emp ies, making new
disco e ies mo e challenging and sca ce, esea che s a e o ced o mi-
g a e ye again o new oppo uni ies (Ay es, 1969).
I is clea ha he issue o esea che s pu suing a speci
fi
c esea ch
a ea is much mo e complex han he pu e Humbold ian endea o o a
esea che (e.g., Laudel and Gläse , 2014). A esea che , pa icula ly so
called
“
no mal scien is
”
ansi ion easily o agendas ha a e well-
unded. (B aun, 2012) Resea che s also look o di e si y in o de o
di
ff
e en ia e his o he wo k om o he scien is s and mi iga e isk
associa ed wi h a na ow ocus. The decision o esea che s o endea o
in a
fi
eld is in e es ing when assessing he e olu ion o a echnology.
Suominen (2013) analyzed he numbe o en an s in and he cohe-
si eness o a
fi
eld by measu ing he in oduc ion o new e ms. The use
o he en an measu e was exempli
fi
ed in he e alua ion o echnolo-
gical p og ession in wo
fi
elds: di ec me hanol uel cells and dye sen-
si ized sola cells. Howe e , he s udy was unable o alida e u he i
Hol on
’
s (1962) analogy o a
fi
ni e space holds ue.
The discussion on communi ies and ac o s is no inconsequen ial o
he b oade opic o echnological eme gence. Eme ging echnology is
de
fi
ned as a echnology ha will yield signi
fi
can bene
fi
s o a wide
ange o economic o socie al sec o s (Ma in, 1995). The cha ac e -
is ics o eme gence a e no el y, pe sis ence, g ow h, and communi y
o ma ion (Suominen and Newman, 2017). These cha ac e is ics a e
o en ansla ed o scien ome ic indica o s enabling he ope -
a ionaliza ion o eme gence. Temple on and Fleischmann (2013) de-
sc ibed eme gence as no iceable h ough he inc ease in ac o s o e
ime.
Howe e , exis ing s udies mos ly ep esen he dynamics h ough
ne wo ks, such as co-au ho ship (Pe ianes-Rod íguez e al., 2010;
Glänzel and Schube , 2005), co-ci a ion (Small e al., 2014), and bib-
liog aphic coupling (Kuusi and Meye , 2007), seldom conside ing he
g ow h o schola s' pa icipa ion and i s unde lying dynamics. E en
hough he dynamic o schola s' pa icipa ion is cen al o Ay es's and
Hol on's wo k (Ay es, 1969; Hol on, 1962), he e a e limi ed s udies
ha quan i a i ely examine he pa icipa ion dynamics o ack he
eme gence phenomenon. This s udy elies on bibliome ic da a wi h
quali a i e in o ma ion acqui ed om a su ey o explo e one dimen-
sion o he eme gence phase o a echnology
—
how esea ch pa ici-
pa ion and communi y dynamics e ol e du ing he eme gence o a new
echnological pa hway.
The s uc u e o his pape is as ollows: he
fi
s sec ion desc ibes
he s udy's backg ound, ocusing on he dynamics o eme ging scien i
fi
c
communi ies and hei link o he li e a u e on echnological eme -
gence. The second pa o he backg ound desc ibes iboelec ic na-
nogene a o (TENG) echnology as a case s udy and wha he measu es
a e expec ed o unco e . The hi d sec ion e iews he da a collec ion
p ocess and he me hodology, ollowed by esul s and discussion in he
ou h and
fi
h sec ions, espec i ely.
2.
Backg ound
2.1.
Eme gence in communi ies o p ac ice
T acing and concep ualizing he eme gence o new echnical in-
no a ions has always been o in e es o schola s, as he inno a ions a e
closely linked wi h economic p ospe i y (Dosi, 1982). In he pas dec-
ades, schola s ha e used di
ff
e en e ms and axonomies o de
fi
ne he
phenomena and he o igins o eme ging echnologies. Schumpe e
(1961) p o ided he seminal explana ion o eme ging echnologies.
Schumpe e depic ed echnological de elopmen as a ci cula
fl
ow
dis up ed by spon aneous changes (p ima ily om inno a i e en-
ep eneu s) o he p e iously exis ing equilib ium s a e. Eme ging
echnologies can be he esul o ei he echnological de elopmen o
scien i
fi
c p og ess.
The idea o he ci cula
fl
ow in echnological change is somewha
analogous wi h Kuhn's scien i
fi
c pa adigm (Kuhn, 1970). Kuhn
in oduced he concep o he pa adigm shi in he con ex o scien i
fi
c
disco e ies, an ac ha aligned wi h he Schumpe e ian no ion ha any
p og ess in science o echnology is he esul o adical change. Kuhn's
iew con as ed wi h he es ablished knowledge o his ime
–
he la e
being ha he d i ing o ce behind scien i
fi
c ad ances was a s eady
accumula ion o knowledge and ideas. Kuhn a gued ins ead ha he
p og ess o science occu s du ing a e olu iona y explosion o new
knowledge, claiming ha scien i
fi
c e olu ion has a cyclical pa adigm.
The cycle begins in a s able pe iod o no mal science, when esea ch is
conduc ed acco ding o a se o accep ed heo ies among scien i
fi
c
communi ies. Resea ch endea o s hen ex end he scope and p ecision
o
he
es ablished
knowledge
in
he
n
o mal
science
phase,
o puzzle-
sol ing phase, which usually has p ede e mined solu ions, p e- cedes a
ise in anomalies ha iola e he
“
pa adigm-induced expec a ions ha
go e n no mal science
”
(Kuhn, 1970). These anomalies begin o
accumula e a ound ce ain pa adigms, o cing science o explo e
al e na i es, o ee alua e cu en heo ies, and
fi
nally o shi o a new
pa adigm. This is simila o Hol on
’
s (1962) image o opening a lode.
Pa adigm shi s and echnological eme gence mani es in changes in
a gi en
fi
eld's communi ies o p ac ice o dynamism. Dynamism in e-
sea ch communi ies is mos ly analyzed h ough esea ch collabo a ion.
The mo i es o in es iga e collabo a i ely s em om six ac o s (Ka z
and Shapi o, 1994): (1) inc eased esea ch cos s, (2) educed commu-
nica ion cos s and a el cos s, (3) ad ances in science ha depend on
in e ac ions among scien is s, (4) inc eased awa eness o he need o
in e disciplina y wo k, (5) poli ical d i e s such as unding, and (6)
inc eased scien i
fi
c specializa ion. Collabo a ion is he co e o com-
muni y c ea ion, as ac o s sha e and lea n om each o he . Scien o-
me ic s udies ha e ex ensi ely examined collabo a ion in a numbe o
a eas, such as s em cell esea ch (Li e al., 2009), g aphene esea ch (L
e al., 2011), uel cells (Suominen, 2014), ola ile o ganic compounds
(Zhang e al., 2010), and global posi ioning sys em esea ch (Wang
e al., 2013).
S udies o co-au ho ship o en do no conside he g ow h o com-
muni ies, a he explaining di
ff
e ences in exis ing communi ies. Ay es
desc ibed scien i
fi
c esea ch as compa able o ocean explo a ion based
on he assump ion o an ocean comp ises a
fi
ni e pool o ideas. As new
esea ch opens new pools o explo e, awa eness o he disco e y
sp eads, en icing a numbe o in es iga o s o join in he explo a ion. As
esea ch is conduc ed, u u e disco e ies become much ha de o
achie e as mos o he
fi
ni e space has been explo ed. This esul s in
fi
eld sa u a ion, leading o new pools disco e ed among new s eams o
science. This p ocess o e olu ion is illus a ed in Fig. 1.
The long dashed line in Fig. 1 desc ibes basic esea ch pa icipa ion.
Fig. 1. Ay es's and Hol on's model o esea ch e olu ion (Ay es, 1969).
In Hol on (1962), he olume o basic esea ch pa icipa ion g ows
apidly a e he opening o a new s eam o esea ch. The inc ease in
human labo wi hin he
fi
eld apidly inc eases he amoun o al eady
known and applied ideas. The e
ff
o needed o
fi
nd one uni o dis-
co e y is highe when less is known abou he subjec . When almos all
he in e es ing ideas ha e been disco e ed, he equi ed e
ff
o o p o-
duce new known and applied ideas diminishes, esul ing in a s eepe
cu e. Howe e , he lack o emaining ideas educes he olume o
esea ch pa icipa ion. Hol on's heo e ical amewo k has emained
empi ically unexplo ed. Howe e , unde s anding how esea ch com-
muni ies g ow and whe e sub-communi ies eme ge would gi e much
insigh o he p ocess o echnological eme gence.
2.2.
T iboelec ic nanogene a o
To unde s and how en an dynamism e eals he eme gence o a
new echnology, he esea ch communi y g ow h o TENG echnology
se es as an example. In en ed in 2011 by Z.L. Wang a he Geo gia
Ins i u e o Technology and
fi
s published in 2012 he TENG is a new
echnology ha can e
ff
ec i ely ha es ambien mechanical ene gy
om a ious mo ions eadily a ailable bu in a sense was ed in ou
daily li es, such as human mo ion, ib a ions, mechanical igge ing,
o a ing i es, wind, and
fl
owing wa e . A nanogene a o comp ises wo
s acked shee s made o ma e ials ha ing dis inc ly di
ff
e en ibo-
elec ic cha ac e is ics, wi h me al
fi
lms deposi ed on he op and
bo om o he assembled s uc u e. Resea ch has shown TENG echno-
logy's p omising applica ions, such as po able elec onics and sel -
powe ed senso ne wo ks (Fan e al., 2012).
TENG echnology has g ea comme cializa ion po en ial mainly due
o i s capaci y o ha es ene gy om he en i onmen . E
ff
o s ha e
been made o explo e applica ions, such as he po en ial o ealize a
sel -sus aining in eg a ed sel -powe ed mic osys em (Zhang e al.,
2015), and i s low-cos ab ica ion p ocess (Qiu e al., 2015). Resea ch
has sugges ed ha TENG echnology can be used as senso s (Allu i
e al., 2015), hyb id ene gy cells (Zheng e al., 2014), po able o
wea able elec onics (Zhu e al., 2013), o la ge-scale ene gy (wind o
ocean wa e) collec ion de ices (Wen e al., 2014).
Compa ed o o he echnologies, TENGs ha e shown ad an ages
such as high ou pu , high ene gy-con e sion e
ffi
ciency, as well as
abundan choices o ma e ials, scalabili y, and
fl
exibili y. The a ea
powe densi y eaches 599 W /m
2
, he olume powe densi y eaches
15 MW /m
3
, and he ene gy con e sion e
ffi
ciency eaches up o 85%.
Speci
fi
cally, he compa ison o TENGs wi h he pe o mances o an-
o he mechanical ene gy ha es e , elec omagne ic gene a o s (EMGs),
demons a es ha he ou pu pe o mance o EMGs is p opo ional o
he squa e o he equency, while ha o TENGs is app oxima ely in
p opo ion o he equency. The e o e, TENGs ha e supe io pe o -
mance when compa ed o EMGs a low equency ( ypically 0.1
–
3 Hz).
Mo eo e , he ex emely small ou pu ol age o EMGs a a low e-
quency makes hem almos inapplicable o d i e any elec onic uni
ha
equi es
a
ce ain
h eshold
ol age
(
≈
0.2
–
4
V).
Thus,
mos
o
he
ha es ed ene gy is was ed. In con as , TENGs ha e an ou pu ol age
ha is usually high enough
(>
10
–
100 V) o such an applica ion and is
independen o equency so ha mos o he gene a ed powe can be
e
ff
ec i ely used o powe di
ff
e en de ices (Wang, 2017; Zi e al.,
2016).
Al hough he es ima ion o wha ep esen s he me apho ical
opening o a lode o he occu ence o a pa adigm shi emains highly
subjec i e, and in he case o TENG echnology only he u u e migh
yield a consensus on i s impac , s ong e idence exis s o suppo
TENGs' pa adigm-shi ing na u e. The in en o , Z.L. Wang, cu en ly
anks
fi
s in ci a ions in he
fi
eld o nano echnology and nanoscience
1
.
He and his esea ch g oup ha e ecei ed mul iple awa ds, such as he
1
h p://www.webome ics.in o/en/node/198.
En e nazionale id oca bu i S.p.A. (ENI) awa d o he ene gy on ie . In
he ENI p ess elease
2
he commi ee highligh ed TENGs as a com-
ple ely new g oup o de ices showing signi
fi
can po en ial in ene gy
e ie al and gene a ion.
TENG echnology is a aluable case s udy o unde s and esea ch
pa icipa ion and communi y dynamics du ing he eme gence o a new
echnological pa hway. TENG esea ch would seem o o
ff
e a me a-
pho ical opening o a lode (Hol on, 1962) o a Kuhnian pa adigm shi
(Kuhn, 1970) used as a s a ing poin o his analysis. The echnology
me ges di
ff
e en aspec s o na u al sciences om ma e ials science
(19% o publica ions), physics (14.1% o publica ions), chemis y (17.5
o publica ions). This c oss-disciplina i y inc eases he applicabili y o
he esul s, bu is should be no ed ha ou da a does no ex end he
na u al sciences.
3.
Da a and me hod
3.1.
Da a collec ion
Two da ase s we e used o e ie e in o ma ion o his s udy: a
scien i
fi
c publica ion da abase and a ques ionnai e. Publica ion da a
was used as a p oxy o unde s and he beha io o esea ch commu-
ni ies in TENG echnology. The sea ch que y used o ob ain he da a
was o mula ed ia keywo ds collec ed and e iewed by TENG expe s
a he Geo gia Ins i u e o Technology. The sea ch was execu ed in May
2018 and e ie ed 1229 eco ds o TENG publica ions om he Web o
Science (WoS) Co e Collec ion da abase. The sea ch que y was limi ed
o he ime pe iod om Janua y 2012 h ough Decembe 2017.
The ques ionnai e was designed o collec in o ma ion on why e-
sea che s selec ed o pa icipa e in TENG esea ch and om wha o i-
gins. This allowed o unde s and he cen al mo i a ion, which is key in
Hol on
’
s (1962) amewo k. Ay es (1969) explained Hol on's ame-
wo k as ollows: ha an ac o en e ing esea ch would be mo i a ed by
he ease o making new disco e ies. The amewo k also sugges s ha
when no mo e easy disco e ies emain, many esea che s
fi
nd new
opics elsewhe e. The ques ionnai e esponden s we e asked, using
open-ended ques ions, wha hei mo i a ions o s a TENG esea ch
we e and, i hey had conside ed d opping he esea ch, could hey
explain why. In addi ion, he opical dis ances be ween esea che s who
joined oge he was a ocal poin o he esea ch. Kuhn's no ion ha
esea che s making pa adigm shi s a e new o he
fi
eld was also es ed
h ough an open-ended ques ion abou wha esea che we e ac i e
p io o hei TENG esea ch. Fu he mo e, he ques ionnai e con ained
an open-ended ques ion o iden i y i he esponden s could iden i y
communi ies ha had eme ged a ound TENG esea ch. This was used o
be e unde s and i ehicles exis ed o suppo communi y c ea ion.
Finally, he ques ionnai e inqui ed abou he esea che s' backg ound
(e.g., yea s in esea ch). The ques ionnai e ecipien s we e 615 au ho s
o TENG publica ions e ie ed om he WoS da abase. Au ho s wi h
missing email in o ma ion we e excluded om he su ey. The ques-
ionnai e is Appendix A.
3.2.
Resea ch pa icipa ion and up ake measu es
The publica ion da a was analyzed using a Py hon sc ip , eading
he downloaded da a om he WoS. The p ocess ead he abula o -
delimi ed
fi
les and ex ac ed he au ho
fi
eld (AF) o u he analysis.
The names lis ed as au ho s o each publica ion we e sepa a ed in o
single en i ies: au ho s. A da a s uc u e was o med o gi e each au ho
a unique ID and o ganiza ion, a lis o co-au ho s, and a lis o used
emails.
O ganiza ions we e connec ed o au ho s in wo ways:
fi
s , au ho
2
h ps://www.eni.com/en_IT/media/2018/07/winne s-o - he-2018-eni-
awa ds-announced.
a
ffi
lia ions ha we e nes ed in a C1
fi
eld enabled each au ho o be
connec ed wi h a speci
fi
c o ganiza ion; second, eco ds ha did no
ha e a clea de e mina ion o au ho o ganiza ions (i.e., no links om
he C1
fi
eld) mean ha only he ep in au ho was a
ffi
lia ed wi h an
o ganiza ion.
The AF was also used o link co-au ho s. Fo each pape au ho , he
sc ip s o ed a lis o co-au ho s. I he au ho s' email add esses we e
a ailable, each au ho was also linked o hei co-au ho s' email ad-
d esses. The sc ip checked he a ailabili y o email add esses and hen
linked email add esses wi h he associa ed ep in au ho s. I mul iple
emails we e p o ided, he sc ip examined i he numbe o emails
co esponded wi h he numbe o au ho s. I he numbe o emails and
au ho s ma ched, he emails we e linked and we e expec ed o appea
in he same o de as he au ho s' names appea ed. Finally, each au ho 's
eco d was linked o he eco d's publica ion yea s, i le, unding o igin,
and scien i
fi
c subjec ca ego y.
The Py hon sc ip ope a ionalized esea ch communi y pa icipa-
ion wi h ou a iables: he numbe o au ho s en e ing yea ly, he
numbe o au ho s exi ing yea ly, and he yea ly coun o ac i e au-
ho s. The
fi
s measu e was de
fi
ned by he numbe o au ho s who
fi
s
published in a gi en yea . The second measu e was de
fi
ned by he
numbe o au ho s published in yea who had no subsequen ly pub-
lished in he
fi
eld (
+
n). This analysis excluded he las wo yea s in
he da ase , since he eliable es ima ions o exi ing could no be made
so nea he end o he ime se ies. The hi d measu e was calcula ed by
coun ing each au ho ac i e in he yea s hey en e ed and exi ed he
fi
eld. I an au ho did no exis on he ac i e au ho lis be o e he las
wo yea s o he ime se ies, hen ha au ho was calcula ed as ac i e
om he ime o
fi
s publica ion o he end o he ime se ies. The
ou h measu e was he numbe o unique au ho s in a gi en yea . This
did no ake in o accoun any o he alues han he amoun o unique
au ho iden i
fi
e s. The di
ff
e ence be ween he ac i e au ho s and he
au ho s' yea ly coun is ha he o me did no equi e au ho s o
publish in each yea be ween hei
fi
s and las publica ion o be e-
ga ded as an ac i e esea che in he
fi
eld.
3.3.
Communi ies o esea che s
To be e unde s and he g ow h o communi ies, indi idual ac o s
we e no he only conside a ion in his s udy; co-au ho ship a bo h
indi idual and o ganiza ional le els was conside ed. The WoS da a was
sliced based on yea s and uploaded o VOS iewe so wa e ( an Eck
e al., 2010). An analysis based on yea s enabled an in es iga ion o
changes in communi y s uc u e h ough communi y o ma ion. Pa a-
me e s used o analyze da a in he VOS iewe we e ull coun ing, in-
cluding all publica ions, no expec a ion o a minimum numbe o ci-
a ions o publica ions, and calcula ions o all au ho s. In he las s age,
au ho s wi h no connec ions o he o he schola s o o ganiza ions
wi hin he da ase we e excluded. The esul s om he VOS iewe we e
impo ed o Gephi o ne wo k analysis. Fo each yea , basic ne wo k
s a is ics we e calcula ed, which allowed o a deepe unde s anding o
ne wo k g ow h.
Communi ies we e also analyzed a he na ional and o ganiza ional
le els. Publica ion eco ds we e connec ed o he communi ies' asso-
cia ed coun ies using ull coun ing. Simila ly, he yea ly o ganiza-
ional-le el ac i i ies we e calcula ed using he ull coun ing o iden-
i
fi
ed o ganiza ion names. To unde s and whe he TENG esea ch
communi ies we e g owing o becoming mo e dispe sed, he
He
fi
ndahl
–
Hi schman Index (HHI) was calcula ed on a yea ly basis o
bo h na ional and o ganiza ional le els. Finally, he de elopmen o
TENG communi ies h oughou he ime se ies was analyzed a an o -
ganiza ional le el. The modula i y algo i hm (Blondel e al., 2008a)
embedded in Gephi was used o unco e TENG esea ch communi ies
om he ull da a.
Majo communi ies we e u he examined o de e mine he geo-
g aphical and hema ic bounda ies o TENG esea ch communi ies. The
geog aphical bounda ies o communi ies we e analyzed using Google's
geocoding API. Each o ganiza ion was geocoded o acqui e hei la i-
udinal and longi udinal in o ma ion. Then, he dis ances be ween he
co-au ho ing au ho s o ganiza ions we e calcula ed. TENG esea ch
communi ies we e sc u inized using opical concen a ion and physical
dis ance measu emen s. Topical concen a ion was calcula ed based on
dis ibu ion o au ho -assigned keywo ds using HHI wi hin each majo
esea ch communi y. Physical dis ance was e alua ed as he a e age
physical dis ance be ween communi ies.
Finally, opical changes wi hin he whole TENG communi y we e
e alua ed. Topical change was calcula ed by ex ac ing e ms om
abs ac s on a yea ly basis. P io o ex ac ing e ms, common scien i
fi
c
publica ion s opwo ds we e emo ed and n-g ams in he abs ac s we e
me ged. Fo each e m ex ac ed, a del a alue was calcula ed as he
di
ff
e ence o he e m appea ing a yea and
+
1. This opical change
alue was used o unde s and he hema ic changes wi hin he esea ch
communi y. The impo an e ms om all majo communi ies we e
quali a i ely compa ed o he o e all hema ic changes.
4.
Resul s
The absolu e olume o TENG esea ch publica ions has been
g owing, and we can iden i y se e al eme gen ac o s (see Fig. 2).
TENG has a clea in en ion da e and
fi
s publica ion da e in 2012,
which pinpoin s he eme gence imewise. The analysis o he e ie ed
WoS da a showed a s ong inc ease in publica ions. Publica ion olume
had inc eased om app oxima ely 50 publica ions in 2012, he yea o
fi
s publica ions, o a high o 402 in 2017. This inc ease o 704 % in
publica ion numbe s is he p oduc o esea ch up ake and is much
highe han he o e all g ow h o scien i
fi
c publishing, which is ap-
p oxima ely 5% pe yea (La sen and Ins, 2010). I also sugges s a clea
pe sis ence, as he echnology has al eady been a ound o se e al
yea s.
4.1.
Quali a i e insigh s om he ques ionnai e
Communi y c ea ion was con
fi
med ia a ques ionnai e sen o
TENG esea che s in he beginning o June 2018. Du ing almos h ee
weeks, 41 o 615 esea che s esponded o he ques ionnai e. The e-
sul s de i ed om su ey analysis a e p esen ed in Table 1, and he
con en o he ques ionnai e is p esen ed in Appendix A. Abou hal o
he esponden s iden i
fi
ed hemsel es as senio scien is s (48.78%),
Fig. 2. The yea ly dis ibu ion o TENG scien i
fi
c publica ions om 2012
h ough 2017.

Table 1
The esul o ques ionnai e.
Resea ch ime and du a ion
Time pe iod (Yea )
Numbe o
Numbe o esponden s
No es
esponden s
(%)
In ol ed in esea ch ac i i ies
Min (1
–
5 yea s)
10
24%
A e (5
–
15 yea s)
17
41%
Max (mo e han 15)
14
34%
In en ion o lea e TENG esea ch
Yes
2
5 %
The easons a e no epo ed.
No
38
95%
In ol ed in p epa ing TENG p ojec o
Yes
34
82%
u u e
No
7
17%
Responden 's cu en
fi
eld o esea ch
Clus e name
Numbe o
Numbe o esponden s
No es
(Clus e numbe )
esponden s
(%)
1
Ene gy ha es ing ma e ial
14
26%
2
Senso s, sel -powe ed senso s, senso
9
17%
ne wo k analysis
3
T iboelec ic nanogene a o (TENG)
9
17%
3
O he
fi
elds
6
11%
e.g. Vascula biology, p in ed de ice, ib a ion, synch o on adia ion echniques, Li-on
ba e y,
fl
exible elec onics, au oma ed d i ing and ac i e sa e y sys em.
4
Nanogene a o s
4
7%
5
Mic o/nano elec omechanical sys ems
4
7%
(MEMS/NEMS)
6
Piezoelec ic elec onics
3
6%
7
Physics
2
4%
9
G aphene
1
2%
10
Mechanical Enginee ing
1
2%
11
Ma e ial science
1
2%
Mo i a ion ac o s o engage wi h TENG
Clus e name
Numbe o
Numbe o esponden s
No e
esponden s
(%)
1
Po en ial applica ion in u u e
26
60%
e.g. Powe sou ce o LED ligh , elec onic de ices, mic o-senso s, wi eless senso ne wo ks,
wea able display, a i
fi
cial elec onic skin, applica ion In e ne o hings (IoT)
2
No el y
6
14%
3
Pe sonal esea ch in e es
4
9%
4
P omising de elopmen end and cu en
4
9%
pe o mance
5
Collabo a ion pu poses
2
5%
e.g. Collabo a ion wi h speci
fi
c companies and colleagues wi hin he esea ch communi ies
6
O he easons
1
2%
e.g. Engaged because o being in a
fi
eld o esea ch hema ically close o TENG.
5
which means hey ha e an independen esea ch-and-de elopmen
posi ion in academia wi h signi
fi
can con ol o e esea ch opics. The
emaining esponden s we e a mid-senio - (26.83%) o junio -le el
(14.63%) posi ions wi h pa ial o no con ol o e hei esea ch opics.
Fo indus y posi ion he esponden s did no ha e senio -le el e-
sponden s, bu included 4.88% mid-le el and 2.44% junio -le el e-
sponden s. Finally, he esponden s included 2.44% holding a eme i us
posi ion.
Almos all esponden s had a
ffi
lia ed hemsel es wi h one o mo e
TENG- ela ed con e ences, annual summi s, o jou nals a icles. Based
on he esponden s' answe s, he majo scien i
fi
c enues o he TENG
esea ch communi y we e iden i
fi
ed as he Nanoene gy and
Piezo onics In e na ional Con e ence, he Ma e ials Resea ch Socie y
Con e ence, and he Nanoene gy and Nanosys ems In e na ional
Con e ence.
Al hough TENG echnology was in oduced in 2012, 41% o e-
sponden s epo ed ha hey had esea ch ca ee s be ween 5 and
15 yea s in leng h, and 34% epo ed a esea ch ca ee o mo e han
15 yea s. Responden s had been engaged wi h esea ch o 12 yea s on
a e age. Acco ding o Table 1, 95% o esponden s would con inue
hei esea ch on TENG and s ay in he communi y. In addi ion, 82% o
esponden s we e hen cu en ly wo king on o planning o p opose
esea ch p ojec s wi h a ocus on TENGs.
Responden s ac i e in TENG esea ch had di
ff
e en esea ch back-
g ounds. Open-ended esponses we e labeled as 11 ca ego ies (see
Table 1). I should be no ed ha each esponden could ha e been a -
fi
lia ed wi h mo e han one clus e . The majo i y o esponden s (26%)
we e ac i e in he opics o ene gy ha es ing ma e ials. The second and
hi d clus e s had a simila a e o a
ffi
lia ed esponden s: 17% each. The
ollowing esea ch clus e s con aining less han 10% o esponses: na-
nogene a o s, mic o/nano elec omechanical sys ems, piezoelec ic
elec onics, physics, g aphene, mechanical enginee ing, and ma e ial
science in gene al.
Rega ding scien is s' main mo i a ions o join he TENG esea ch
communi y, he answe s we e clus e ed in o six main ca ego ies (see
he las sec ion o Table 1).
“
The po en ial applica ions o TENG ech-
nology in he u u e
”
and/o
“
TENG is a mul i-pu pose eme ging
echnology
”
a ac ed almos 60% o esponden s o conduc TENG
esea ch.
“
No el y cha ac e is ic o TENG echnology
”
was he second
mos impo an eason why esponden s (14%) decided o join he
TENG esea ch communi y. Abou 9% o esponden s epo ed ha
pe sonal esea ch in e es s mo i a ed hem o engage wi h TENG e-
sea ch. Ano he 9% o esponden s iden i
fi
ed
“
he apid de elopmen
”
and
“
he cu en high pe o mance
”
o TENGs as he mo i a ion o
pu suing TENG esea ch.
“
Building esea ch ne wo k
”
and
“
Collabo a-
ion wi h indus y
”
we e he easons o only 5% o esponden .
O e all, esponden s seemed o associa e hei TENG esea ch wi h
esea ch hey had been conduc ing o a longe pe iod. This is appa en
om he ac ha he majo i y o esponden s a
ffi
lia ed hemsel es wi h
TENG esea ch o a pe iod longe han he echnology's in en ion da e.
Resea che s we e engaging wi h TENGs mos ly due o he in insic
mo i a ion (Lam, 2013) o applying TENGs as a mul ipu pose ech-
nology.
4.2.
The esea ch communi y analysis esul s
Cen al o he no ion o Hol on (1962) was ha a new p omising
fi
eld would a ac esea che s o join ha
fi
eld. The idea u he de-
eloped by Ay es (1969) claimed ha esea che s a e p one o exi a
fi
eld i i does no yield esul s. Fo TENGs, he esul s sugges a s ong
upwa d end in he size o he esea ch communi y, as seen in Fig. 3.
By he end o 2017, a esea ch communi y ha began wi h 200 au ho s
in 2012 has g own o app oxima ely 1500 membe s by he end o 2017.
The g ow h a e o new esea che s joining he
fi
eld is also signi
fi
can .
While in he
fi
s h ee yea s, new publishing esea che s emained
unde 300 membe s, by he end o 2015, nea ly 600 new membe s we e
doing TENG esea ch.
Au ho dynamics we e calcula ed h ough ou measu es: unique,
ac i e, new, and lea ing au ho s (Fig. 3). Du ing he
fi
s yea o pub-
lica ion, he
fi
eld al eady had 261 au ho s. This is signi
fi
can i we
conside ha TENG was in en ed la e 2011 and
fi
s published in ea ly
2012. I sugges s a apid mig a ion o esea che s om o he
fi
elds ha
we e hema ically close o TENG. This is also suppo ed by ou ques-
ionnai e esul s. A he end o 2012, 191 au ho s le he esea ch a ea.
By
“
lea ing
”
we e e o he au ho s who did no publish new esea ch
h oughou he es o he ime se ies. This esul ed in 73% o au ho s
who did no publish esea ch in any subsequen yea s. Since hen, he
numbe o au ho s lea ing he a ea ha e emained ela i ely s able and
much lowe han ha o new esea che s joining he
fi
eld.
In addi ion o pa icipa ion g ow h in he
fi
eld, eme gence equi es
some cohe ence. TENG esea ch is a highly coope a i e esea ch a ea.
Co-au ho ship o TENG publica ions desc ibes p og ess o TENG com-
muni y de elopmen . Fig. 4 shows he co-au ho ship changes
h oughou he s udy's pe iod. As seen in he
fi
gu e, wo dis inc clus-
e s o esea che s a e iden i
fi
able, bo h connec ed by a ew cen al
au ho s bu sepa a ed by a numbe o esea che s who do no co-au ho
b oadly. In he
fi
gu e, we can also clea ly iden i y he cen al ole o he
in en o , see as he la ges o ange node.
Complemen ing Fig. 4, he analysis o he yea ly ne wo k o ma ion
o TENGs enables unde s anding o he a ea's g ow h. Ne wo k mea-
su es a e shown in Table 2. The a e age deg ee, he a e age o all
au ho connec ions wi h o he au ho s, has emained ela i ely s able.
An au ho has, on a e age, ou o
fi
e co-au ho s in a gi en yea . Co-
au ho ship is o en s udied on a pape le el, whe eas esul s he e ocus
on he communi y a ound a esea che pe yea . The li e a u e shows
ha pape -le el co-au ho ship is on a e age app oxima ely ou au ho s
(Glänzel and Schube , 2004). In his con ex , TENG esea ch does no
di
ff
e om o he scien i
fi
c endea o s.
When he au ho coun inc eases he diame e o he ne wo k, he
longes pa h in a ne wo k g ows as new esea che s join a he ends o
he ne wo k, wi h limi ed coope a ion wi hin he communi y. The
a e age pa h leng h also inc eases, which means no only one o wo
esea che s a e a he ends o he ne wo k, bu he o e all communi y is
becoming mo e spa se. Ne wo k diame e , he a io be ween au ho
connec ions o all possible connec ions, also dec eases o suppo he
no ion o a mo e spa se communi y.
One cha ac e is ic o eme gence is global p esence (Ro olo e al.,
2015). Al hough he esul s o his s udy indica e ha he communi y
has g own in e ms o indi idual ac o s, hey ell li le o he commu-
ni y's global g ow h. In Fig. 5, he global sp ead o TENG esea ch is
e iden . The
fi
gu e shows ha while a communi y is g owing by he
numbe o ac o s, i eally is only cen e ed on h ee coun ies: he USA,
China, and Sou h Ko ea; all o he coun ies show only modes pub-
lica ion coun s. The numbe o coun ies wi h a leas one TENG pub-
lica ion has g own om se en in 2012 o 32 in 2017. This de elopmen
is simila o he
fi
ndings in he eme gence o uel cell echnology
(Suominen, 2014), whe e he numbe o coun ies g ew linea ly. In-
e es ingly, i a h eshold o coun ies wi h a leas
fi
e publica ions is
used, as in Suominen (2014), only wo coun ies me ha limi in 2012,
g owing o 10 in 2017. A simila pa e n was seen in uel cell ech-
nology.
The connec ion be ween au ho s and coun ies iden i
fi
ed he spa se
con ibu ions om all excep he co e coun ies. The majo i y o au-
ho s in he da ase we e a
ffi
lia ed wi h an o ganiza ion based ei he in
China, he USA, o Sou h Ko ea. In 2012, he numbe o publica ions
om China inc eased om 11 in 2012 o 226 in 2017 and he USA
inc eased om se en in 2012 o 120 in 2017. I should also be no ed
ha some au ho s can ha e se e al a
ffi
lia ions, which we e whole
coun ed o acc edi each men ioned coun y. No able inc eases in he
numbe o publica ions ha e aken place in Sou h Ko ea. While Sou h
Ko ea had jus h ee publica ions in 2013, in 2017 i s publica ion
numbe had g own o 84. All o he coun ies emained a an ex emely
Fig. 3. Size o he TENG esea ch communi y. The
fi
gu e shows all ac i e au ho s, unique au ho s yea ly, new au ho s, and au ho s lea ing. The ime se ies o
au ho s lea ing concludes a he end o 2015, as he calcula ions we e based on an au ho con inuously publishing.
low publica ion g ow h a e. Coun ies such as he Uni ed Kingdom and
Ge many, which accoun o a signi
fi
can amoun o global scien i
fi
c
p oduc ion, had less han 20 publica ions each.
The HHI highligh ed he concen a ion o he scien i
fi
c communi y.
On a na ional le el, TENG esea ch was signi
fi
can ly concen a ed. HHI
alues had g own om 29% in 2012 o a high o 37% in 2013, and hen
o 25% in 2017. Fo compa ison, he o e all concen a ion o scien i
fi
c
esea ch is app oxima ely 10% (Veugele s, 2010). Ul ima ely, al hough
he TENG esea ch communi y appea s o be global, i has ac ually been
concen a ed in a small numbe o coun ies.
A an o ganiza ional le el, he Chinese Academy o Sciences and he
Geo gia Ins i u e o Technology a e he co e o ganiza ions in he
fi
eld.
F om 2012 h ough 2017, hese wo o ganiza ions accoun ed o nea ly
30% o publica ions, o en wi h esea che s sha ing a
ffi
lia ions.
Compa ing he wo la ges o ganiza ions wi h he es , i is no ewo hy
ha he 34 nex -la ges o ganiza ions p oduced oughly he same
amoun o publica ions as he wo la ges . Table 3 highligh s o gani-
za ions wi h o e 20 publica ions, 2012
–
2017.
Focusing on he eme gence cha ac e is ic o global p esence, he
numbe o o ganiza ions had g own mo e d ama ically han has he
numbe o coun ies wi h a signi
fi
can ole. F om he s a o 2012 o
he end o 2017, he numbe o o ganiza ions had g own om 27 o
274, as seen in Table 4.
Using he HHI o o ganiza ional au ho ship, TENG esea ch has no
been a pa icula ly concen a ed esea ch communi y, especially when
compa ing on a na ional le el. Table 4 shows ha he
fi
eld con inued o
become mo e concen a ed om he beginning o 2012 o he end o
2015, when i began o diminish in concen a ion o he end o 2017. I
is no ewo hy ha e en hough he wo la ges o ganiza ions ha e
played a signi
fi
can ole, he inc ease in he numbe o o ganiza ions
keeps he HHI alues small. The communi y o ma ion is isualized by
co-au ho ship ne wo k on an o ganiza ional le el, as seen in Fig. 6. In
he
fi
gu e, s ong links a e e iden be ween he Chinese Academy o
Sciences and he Geo gia Ins i u e o Technology seen as he la ges
g een nodes. Howe e , i is wo h men ioning he dual posi ion o Z.L.
Wang as he cen al au ho in Fig. 4; Wang has led he TENG esea ch in
bo h leading o ganiza ions. This connec ion migh o e emphasize he
link be ween he o ganiza ions.
The co-au ho ship ne wo k om 2012 h ough 2017 was used o
e alua e he ypes o communi ies o med (as seen in Fig. 6). The
communi ies we e clus e ed using he modula i y algo i hm (Blondel
e al., 2008b). The analysis esul ed in 87 communi ies, among which
only ou had o e 5% o he au ho s. The la ges o ganiza ional clus e
(17.32 %) was cen e ed in Sou h Ko ea. The second la ges (16.23%)
was cen e ed in he wo la ges o ganiza ions, complemen ed wi h a
numbe o geog aphically spa sed Chinese o ganiza ions. The hi d
la ges communi y (11.4 %) was a sp ead o cen al o ganiza ions, wi h
Soochow Uni e si y con ibu ing a signi
fi
can po ion o he publica-
ions. The ou h la ges clus e (7.68%) was a mix o No h Ame ican
and Chinese o ganiza ions, such as Huazhong Uni e si y o Science &
Technology and Uni e si y o To on o. In addi ion o he la ge com-
muni ies eme ging, i is signi
fi
can o no e ha Fig. 6 shows a numbe
o o ganiza ions no connec ed o he o e all communi y o TENG e-
sea ch (in g ay). These o ganiza ions emained isola ed om 2012
h ough 2017.
To
be e
unde s and
he
communi ies
embedded
in
F
h
i
g
e.
6,
physical dis ance and hema ic concen a ion o each o he ou la ges
communi ies was calcula ed. As can be seen in Table 5, he hema ic
concen a ion and physical dis ance had a modes ly nega i e co ela-
ion (
=
−
0.44, p
<
0.05). The ela i ely low co ela ion did no allow
o s ong conclusions, bu he able does clea ly demons a e ha in
addi ion o he clus e o au ho s, new communi ies g ew om e-
gionally bound spaces, such as a communi y ha has a high con-
cen a ion o Sou h Ko ean o ganiza ions.
Table 6 desc ibes he hema ic changes in TENG esea ch o e all.
The mos impo an e ms a e cen e ed on he co e echnology ele-
men s. Te ms such as
“
TENG,
” “
iboelec ic,
”
and
“
de ice
”
emain
among he mos eme gen . The only signi
fi
can ly eme gen applica ion
on he able is he eme gence o senso s and wea able applica ions.
Conce ning di
ff
e en communi ies, he second communi y, on
which mos TENG esea ch is cen e ed including he in en o o he
echnology, he mos equen ly used e ms we e
“
TENG
”
o
“
ene gy
ha es ing
”
. The e m occu ence sugges s ha his communi y has
been ocused on he co e echnology. O he communi ies a ound he
echnology ha e had di
ff
e en hema ic o ien a ions. The
fi
s com-
muni y was hema ically concen a ed on impo an e ms such as
“
sel -
powe ed senso a ays
”
and
“
silk
fi
b oins.
”
These e ms a e highligh ed
as hey a e no p esen ed in he o he communi ies. The hi d com-
muni y appea s o ha e been specialized h ough e ms such as
“
sel -
healing
”
and
“
TENGs
”
. The ou h communi y was connec ed h ough
e ms such as
“
in i o ene gy ha es ing
”
and
“
a e ial pulse mon-
i o ing,
”
which did no appea in o he communi ies. In e es ingly,
hese di
ff
e ences a e no isible in Table 6; hey a e much sub le . The
selec ed e ms a e highligh ed as hey appea in a pa icula communi y
Fig. 4. Co-au ho ship in TENGs, 2012
–
2017. Colo ep esen s clus e esul ing om an analysis done by VOS iewe . The ne wo k g aph is a ailable online a h p://
a hosuominen.
fi
/TENG/au ho / and he ela ed da a
fi
le a h p://a hosuominen.
fi
/TENG/au ho /au ho _TENG.gex . (Fo in e p e a ion o he e e ences o colo in
his
fi
gu e legend, he eade is e e ed o he web e sion o his a icle.)
Table 2
Ne wo k measu es o each yea o TENG co-au ho ship ne wo ks.
Ne wo k measu e
2012
2013
2014
2015
2016
2017
Nodes
91
128
233
568
763
1094
Edges
365
579
1107
2792
3863
5680
A e age deg ee
4.011
4.523
4.751
4.915
5.063
5.192
Ne wo k diame e
5
4
5
7
9
9
G aph densi y
0.089
0.071
0.041
0.017
0.019
0.01
A g. pa h leng h
2.216
2.121
2.709
3.105
3.439
3.682
bu a e no isible in any o he majo communi y.
5.
Discussion and conclusion
In his pape , we s udied he au ho ship dynamics o a newly
eme ging esea ch
fi
eld
—
TENG echnology. The aim was o
fi
nd he
cha ac e is ics o esea ch communi y de elopmen . This is impo an
because s udies analyzing echnological eme gence usually use e ms as
a measu emen , while he heo e ical backg ound on eme gence would
sugges a b oade an age poin (e.g. Ay es, 1969). While au ho s such
as Kuhn (1970) ocused on he pa adigm shi , and mo e con empo a y
s udies on echnological eme gence ha e ocused on he cha ac e is ics
o a echnical en i y (e.g. Ro olo e al., 2015), a esea che 's decision o
join an eme gen
fi
eld is cen al o i s eme gence and de elopmen .
The e ha e ce ainly been s udies on esea che mo i a ions (Lam,
2013), bu he li e a u e on au ho s' decisions o join a new esea ch
fi
eld does no eally exis .
In his s udy, we ound ha a no el disco e y quickly engaged e-
sea che s o join ha disco e y's
fi
eld. Sp eading h ough he cen al
ac o s, new schola s joined he esea ch on he pe iphe y o he au ho
ne wo k. Wi hin six yea s, a s ong o ganiza ional ne wo k had
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