The Visualization of Collaboration among Iranian Researchers on Nanotechnology: A Social Network Approach

Mohammad Hassanzadeh 1, Reza Khodadust 1, Tahereh Hassanzadeh 2 ,Simeon Yates 3 and Babak Akhgar 3 1- Tarbiat Modares University, Tehran, IRAN 2- Department of Computer Engineering and IT, Azad University, Branch of Qazvin, Qazvin, IRAN 3- Sheffield Hallam University UK [email protected] , [email protected], [email protected] [email protected]

Abstract — In this article, we analysed collaboration among comprehension [5]. Some approaches focus on the actors Iranian researchers on nanotechnology by using graph- involved and others focus on the set of related activities [14]. theoretical approaches. Data were collected from Science Statistical and structural analysis of co-authorship networks can Citation Index (SCI) via the Web of Science databases advanced be a useful tool for analysing relationships between various search option during 1991-2011 with query made from researchers within a scientific field [8]. Such networks reveal nanotechnology tree terms, identified by Inspec and Compendex the persistent cohesive research collaboration and clustering in thesaurus. The spatial distribution of network nodes was mapped the network may represent a knowledge domain [5]. Also, a with the Kamada Kwai algorithm. Spectral clustering algorithm bibliographic network is important information for researchers used to identify the clusters for the network of co-authoring when doing a research survey. When a researcher is getting countries to analyse the relationship and communities in into unfamiliar field of research, grasping overview of the networks. The period of study divided into 5 sub-periods and research field, such as bibliographic network, is important [7]. performed analysis on each sub-period. Findings well depicted the trend in Iran’s nanotechnology research. We also indicated In the twenty-year development vision of Islamic Republic the most productive nodes & nodes with high betweenness of Iran up to 2025, considerable Emphasis has been placed on centrality, dominant influence, high authoring burst and high scientific development in new technologies, especially in novelty from the view-point of intellectual at the author and nanotechnology, and in the expansion of scientific country level in Iranian nanotechnology research. The primary collaboration. Such planning and policy making requires the value of this article lies in extending the understanding of the good information concerning available scientific abilities. authoring patterns in Iranian nanotechnology community. This Although the collaborative research has large benefits in here work also has implications for researchers & science policy has been little effort to illustrate international co-authorship making. and authors' collaboration in the Iranian nanotechnology field.

This article is an attempt to fill this gap. Keywords- Iranian nanotechnology; information Visualization; information networks; CiteSpace. This research aimed to analyse and visualize individual’s co-authorship network and the network of co-authoring I. INTRODUCTION countries and to measure the rate of co-authorship at the author To gain insight into today’s large data resources, data and country level in Iranian nanotechnology research. The mining extracts key patterns [16]. Co-authorship studies as results of this study can inform scientific policy makers on the kind of data mining approach to bibliographic records provides collaboration level (regional, national and international), the a window on patterns of collaboration among the academic structure of scientific collaboration networks and collaboration community [5]. While collaboration is an old concept, the patterns. actual study of scientific collaboration is somewhat more recent. At a macro level there are, in general, three major types The remainder of this paper is organized as follows: of factors driving research collaboration: intellectual, Section 2 discusses research background. Section 3 describes economic, and social. At a micro level, collaborative projects to data collection and analysis methods. Section 4 presents the are driven by different motivations depending on the specific collaboration network in the Iranian nanotechnology field. contexts [14]. Section 5 provides some concluding remarks. In terms of generic network theory, a social network II. LITERATURE REVIEW consists of nodes (social actors) and their links (relationships). There has been a steady growth in the study of co- The collaboration social network in scientific research is a very authorship in the field of nanotechnology over the last 10 years. important category of social networks [15]. Studies use In most cases the data for such studies has come from information visualization techniques to enhance nanoscience journals, nanobank and the ISI Web of Science.

None of these studies provided a mapping the co-authorship IV. ANALYSIS OF DATA network and the network of co-authoring countries. 4.1. The nature of co-authorship network Schummer [13] carried out analysis of over 600 articles Table 1 summarizes the size of the authoring space and published in "nano journals" in 2002 and 2003, and details of individual networks and the merged network. The demonstrated that the average 3.1 nano collaborations had one size of the authoring space in a given time slice is the number co-authored article. of authors that have at least one publication within the given time slice; the size is generally increasing over time. The size Milojevic [11] using social network analysis has traced for 2011 is smaller as the 2011 data are still incomplete. nanotechnology documents from1970 to 2004. The results indicate that two-thirds of nanotechnology authors are linked TABLE I. TIME SLICING AND THRESHOLD SETTINGS IN CITESPACE FOR CO- together by more than one independent path. AUTHORSHIP NETWORK OF IRANIAN NANOTECHNOLOGY RESEARCHERS Lin [10] explored the 20 top journals in 2010 in terms of 5-year Criteria Authoring No. No. Slices space size Nodes Links impact factor in nanotechnology counting authors of each document and their collaborators. Characteristics of the C CC CCV distribution of authors in documents and the distribution of 1991-1995 1 2 20 4 4 6 1996-2000 2 2 20 8 0 0 collaborators revealed that the distribution of authors is a 2001-2005 3 2 20 247 22 33 Weibull distribution and the distribution of collaborators is 2006-2010 4 3 20 4632 543 630 Poisson distribution. 2011-2011 3 3 20 2501 258 259 Total (Unique) 7392 827(681) 928(896) One only one study, Hassanzadeh and Khodadust [4] explored the linkages between authors in relation to nationality. Map 1 shows co-authorship network of the most prolific Hassanzadeh and Khodadust looked at Iranian nanotech Iranian nanotechnology authors. The co-authoring network in research between 1991 to 2010 listed in the ISA Web of each time slice represents approximately the top 1% prolific Science. They used the search strategy "TS = nano* AND CU authors. The merged co-authorship network consists of 681 = iran" and employed Excel, histcite and pajek software tools. unique authors along with 896 co-authorship links among They discovered that Iranian nanotechnology publications from them. Which collectively made 827 appearances in these time 2 records in 1991 grew to 1,883 records in 2010. More than slices. In other words, 17.65% of authors appeared in more 80% of articles were published after 2008. The majority of than one time slice. Publications between 1991 and 1995 are most common co-authors were from Iran (77.8%). Masoud shown in dark blue, 1996 and 2000 in light blue, 2001 and Salavati Niyasr with 133 in the first rank and Alireza Ashrafi 2005 in green, 2006 and 2010 in yellow and 2011 in grey. with 99 documents in the second rank of the most prolific Links among authors are co-authorship, which is undirected. authors. This paper builds upon this work and explores the The colours of co-authorship links among authors is by the first visualization of this social-network analysis. year rule that two author were co-author. With regard to map 1, the co-authorship network of Iranian Nanotechnology III. METHODOLOGY publications consists of the main four super clusters. Our research focused on all publications of Iranian The size of each node is proportional to the number of nanotechnology research between 1991 and 2011. Data were nanotechnology field documents that that node (author) has collected on August 5 2011 based on query Made with 65 published. The colours of the tree rings indicate the time terms of the nanotechnology tree in the Science Citation Index patterns of an author in the nanotechnology field. For example, Expanded (SCI-Expanded) collection via the ISI Web of Ashrafi AR Node in middle map 1, the largest authoring circle Science database advanced search. is filled with colours from yellow to grey. This pattern CiteSpace, a Java application developed by Chaomei Chen indicates that Ashrafi AR has published the majority of their of the Information Science and Technology College of Drexel documents (65 document) in the fourth five-year period (2006- University was used for the co-authorship analysis. In this 2010) and that they have not published documents prior to this software there are three sets of threshold levels for co- and has published a very small percentage (ten remaining authorship networks, namely authoring threshold (c), co- documents) in 2011. Esfarjani K Node top right corner of map authorship threshold (cc), and co-authorship coefficient 1 shows a different pattern. Green rings and a thin layer of threshold (ccv). The static visualization of co-authorship yellow dominate the Esfarjani K node. This pattern shows that network of Iranian nanotechnology publications was done by Esfarjani K has published the most of their documents (seven once choice "author" and threshold 1,2,20; 4,3,20; 3,3,20 and of the eleven documents) in the green time slice; namely 2001- one more "country" and threshold 1,1,1; 1,1,1; 1,1,1. Other 2005. options were adjusted as follows: select the 30 top most prolific nodes per slice, and cosine co-authorship coefficient was used for measurement strength of each co-authorship link in within per time slice. The 21-year time interval between 1991 and 2011 was divided into four 5-year time slices (the Beginning from 1991-1995 and the end with 2006-2010) and one 1-year time slice for 2011 (2011-2011).

information between actors (the word actor refers to a person, organization, or nation that is involved in a social relation), an actor who is situated on the geodesics between many pairs of vertices is more central [12]. Node is pivotal if its betweenness centrality value were greater and equal to 0.1. To identify pivotal node, is illustrated only without global pruning version of the larger network. According to table 2, Khodadadi AA, Heravi MM, Golestani-Fard F and Habibzadeh S have respectively The largest betweenness centrality ratio after Moghaddam AB.

TABLE II. PIVOTAL NODES IN THE MERGED CO -AUTHORSHIP NETWORK IN IRANIAN NANOTECHNOLOGY PUBLICATIONS Row Half Author BC frequency Burst ∑∑∑ year life Map 1. The cluster view from co-authorship network of Iranian 1 Moghaddam AB 0.15 22 3.21 1.56 2006 0 Nanotechnology publications. Lines in various colours shows years 2 Khodadadi AA 0.12 27 5.61 1.87 2006 0 Where two researchers have published Joint publications. Red circles 3 Heravi MM 0.1 11 1 2007 2 4 Golestani-Fard F 0.1 11 1 2006 0 indicate burst of productivity during the entire interval. Prolific authors 5 Habibzadeh S 0.1 4 1 2007 0 have shown with Larger label.

Kleinberg’s burst-detection Algorithm can be used to According to Fig. 1, After the Alireza Ashrafi, Ali Morsali reveal the sharp increases in authoring of one author at and Masoud Salavati Niasari respectively with 63 documents nanotechnology field. Burst-detection will determine whether (1.37 Per cent) and 60 documents (1.30 Per cent) allocated 2th the publication of one author In terms of statistical has and 3th ranks of the prolific authors to themselves. In addition considerable surges during short time interval within whole to Mohajerzadeh S were prolific author in terms of production time period. It is valuable for publication analysts to make of science in nanotechnology field, has the largest clear what and when surge the number of a specific author Betweenness Centrality (0.08) toward prolific authors ranked publication. According to table 3, The strongest authoring in Fig. 1. Therefore, this author has dominant influence on burst (11.63) has been apparent in Enayati MH authoring Iranian nanotechnology field community. Fig. 1 shows the history. So that our analysis will demonstrate this author is most productive in terms of whole number of documents that One of The most active Iranian nanotechnology authors in they have produced in the entire dataset. 2007. 75 frequency 80 0.1 TABLE III. TEN AUTHOR WITH HIGH AUTHORING BURST IN THE MERGED 63 60 CO -AUTHORSHIP NETWORK OF IRANIAN NANOTECHNOLOGY PUBLICATIONS 60 0.08 46 44 44 44 43 42 Row Burst Burst Waiting 38 37 35 35 0.06 40 Author Burst Begin End Span Time 0.04 1 Enayati MH 11.63 2007 2007 1 3 20 2 Ashrafi AR 11.38 2006 2006 1 0 0.02 3 Iranmanesh A 10.61 2007 2007 1 0 0 0 4 Karimzadeh F 9.62 2007 2007 1 1 … … … - 5 Salavati-Niasari M 9.08 2006 2006 1 0 6 Kassaee MZ 8.34 2008 2009 2 0 7 Akhavan O 7.98 2006 2006 1 0 ZadAI

Davar Davar F 8 Taghavinia N 7.88 2003 2006 4 0 Salimi A Salimi Salavati Simchi A Simchi

Morsali A 9 Shahrokhian S 7.67 2007 2007 1 0 Ashrafi Ashrafi AR EnayatiMH Sadrnezhaa

GhorbaniM 10 Ganji MD 7.5 2010 2011 2 -1 Mohajerzad DinarvandR Taghavinia N Figure 1. Prolific authors of co-authorship network of Iranian Nanotechnology publications, (There is 6027 citing authors and 17952 co- Sigma ( Σ) is introduced as a measure of scientific novelty. authorship link between them) Sigma is defined as [2]. Table 4 shows authors that are likely to represent novel ideas. A node centrality will determine the importance of the node’s position in a network [1]. Social network analysis TABLE IV. THE NODES WITH HIGH NOVELTY VALUE (> 1) IN CO - provides a set of centrality measures like degree, betweenness, AUTHORSHIP NETWORK OF IRANIAN NANOTECHNOLOGY PUBLICATIONS and closeness centrality [9]. In addition to, there are other Row Author ∑∑∑ year BC Burst frequency measures of centrality [6]. A betweenness centrality approach 1 Khodadadi AA 1.87 2006 0.12 5.61 27 rests on the idea that To what extent may a person control the 2 Shahrokhian S 1.84 2007 0.08 7.67 20 flow of information due to his or her position in the 3 Mortazavi Y 1.67 2006 0.08 6.81 26 4 Moghaddam AB 1.56 2006 0.15 3.21 22 communication network. The more a person is a go-between. 5 Taghavinia N 1.55 2003 0.06 7.88 43 If we consider the geodesics (the shortest path between two 6 Moshfegh AZ 1.41 2006 0.07 5.21 30 vertices) to be the most likely channels for transporting 7 Salavati-Niasari M 1.41 2006 0.04 9.08 60

8 Mazaheri M 1.38 2006 0.08 3.98 15 on Iranian nanotechnology researchers. In among Asian 9 Mohajerzadeh S 1.36 2004 0.08 3.92 35 10 Eftekhari A 1.35 2005 0.07 4.19 13 countries, Malaysia, Japan and India had respectively, the 1nd to 3nd ranks. Taiwan, Ukraine, New Zealand, Morocco, United Arab Emirates, Finland, Oman, Mexico 4.2. International Co-authorship and Libya represent countries that the lowest co-authored Table 5 shows the size of the authoring space and details of paper has been published with Iranian nanotechnology individual networks and the merged network. The merged researchers. Iran had a scientific collaboration with nine International Coauthorship network consists of 45 unique countries (except Iran) from Organization of Islamic countries along with 63 co-authorship links among them. Cooperation (OIC) Fifty-seven Member States during the which collectively made 89 appearances in these time slices. time period under the study. In terms of the amount In other words, 49.44% of countries appeared in more than collaboration with these countries, Malaysia and United one time slice. Arabic Emirates had respectively the highest and lowest number of co-authored paper with Iran in SCI during the TABLE V. TIME SLICING AND THRESHOLD SETTINGS IN CITESPACE FOR mentioned years. Azerbaijan, Egypt, Syria, Turkey, THE NETWORK OF CO -AUTHORS ’ COUNTRIES Morocco, Libya, Oman is placed respectively after 5-year Criteria authoring No. No. slices space size Nodes Links Malaysia, on among the 2nd to 8nd ranks.

C CC CCV 1991-1995 1 1 1 2 2 1 1996-2000 1 1 1 2 2 1 2001-2005 1 1 1 13 13 12 2006-2010 1 1 1 43 43 55 2011-2011 1 1 1 29 29 31 Total(Unique) 89 89(45) 100(63)

with regard to the time zone view, the network of co- authors’ countries is consists of the main four super cluster that using spectral clustering algorithm was found these four super cluster, includes seven smaller cluster separate completely.

Figure 2. Iranian co-authorship frequency with co-author countries

According to distribution Iranian collaboration with countries of different continents, there are 3 American countries, 14 Asian countries (except Iran), 2 Oceania country, 2 African countries & 23 European countries. Fig 3 demonstrates the situation of co-authored papers of each continent has been published with Iranian nanotechnology researchers by the frequency. As shown in Fig 3, Europe continent had the most number of co-authored papers with Iranian in SCI in comparison with the other continents. Asian & America continents is placed respectively after Europe, on

the 2nd & 3nd ranks. Map 2. The time-zone view from an un-pruned conceptual modelling of the network of co-authors’ countries obtained from Iranian Nanotechnology publications. countries with the highest number of co- authored paper with Iran have shown with larger label.

Fig. 2 shows the frequency of collaboration with different countries in nanotechnology discipline. Iranian nanotechnology collaborated with 44 countries. In nano, the Canada has the highest number of co-authored papers with Iran; America & England is placed respectively after Canada, on the 2nd & 3nd ranks. In addition to Canada were prolific co-author country in terms of collaboration with Iran in nanotechnology field, has the largest Betweenness Centrality (0.09) toward other countries in Figure 2. Therefore, this country has dominant influence Figure 3. Iranian co-authorship frequency with co-author continents

With Sorting an Iran's co-authorship network in the field of nanotechnology with other countries obtained from the Citespce software (Excel file) based on the year, following results are obtained.

TABLE VI. THE BEGINNING CO -AUTHORSHIP OF IRANIAN NANOTECHNOLOGY RESEARCHERS WITH OTH ER COUNTRY

First year that iran Countries had Scientific production With other countries 1991 England 2001 Canada, Australia, Japan 2002 France, India, Netherlands, Wales 2003 America 2004 Italy, Morocco 2005 Swedish Map 3. An international collaboration network of 45 countries and 63 2006 Malaysia, Germany, Azerbaijan , Singapore, collaborative ties. Seven collaboration clusters are identified based on the Switzerland, Spain, Denmark, Romania, China, strengths of collaborative ties. Russia, Egypt, Belgium, Portugal, Syria, Turkey, Pakistan, Check Republic, Ireland, Croatia, Greece, Taiwan, Ukraine , United Arab Emirates, Countries Betweenness Centrality range is between Finland, Oman, Libya zero and 1.91 . Iran had the largest betweenness centrality. 2007 Serbia After Iran, respectively, Canada, Sweden, Japan, Denmark 2008 Thailand, Slovakia and the United States had the highest betweenness 2009 South Korea 2011 New Zealand, Mexico centrality. Iran distance range with other countries is between zero and one. Iran has been 41 neighbours. Mexico, Czech-Republic & Syria is not connected with From 1991 to 2000 ( First and second five -year period), the Iran by an independent path namely they is not belong to only Colleague or the main colleague of Iranian its domain. nanotechnology scientists was from “England” . Regardless of 0.09 0.09 Iran can be said that in the third five-year period, the main 0.1 colleagues were respectively from "Canada", "America", 0.08 "Australia" and " France" countries. In the fourth five -year 0.05 period, "Canada", "America", "England" and "Germany" 0.06 0.04 respectively is placed in 1th to 4th ranks. Also, in the end one- 0.04 BC 0.01 year period, Malaysia was Iran's main Colleague . 0.02 Capturing the big picture of international collaboration at a 0 macroscopic level and simultaneously linking to subject matters at finer-grained granularities is a long -standing challenge for computational methods [3]. The map 3 is constructed with two layers of information. The base layer is a co -author network of collaborating countries between 1991 and 2011; Figure 4. Betweenness Centralitycountry of co -author countries with Iran at The thematic layer aggregates individual countries into nanotechnology clusters such that countries in the same cluster have tighter collaboration ties than those in different clusters. The nature of According to table 7, preparation (#4) cluster was the most each cluster is characterized by nanotechnology publications active cluster in terms of authoring burst and kalteh (#5) collaboratively written by researchers from these countries. clusters is placed on 2th rank. Also, The strongest authoring Cluster labels shown in map 3 were selected by log-likelihood burst (5.73) has been apparent in France authoring history. So ratio (LLR) algorithm from the titles of the collaborative that our analysis will demonstrate preparation (#4) cluster publications. In Cluster 4, preparation is the predominant topic countries were from the most active co -author countries with for collaborating researchers from Portugal, Singapore, Wales, Iranian nanotechnology researchers to 2007. Taiwan, Morocco, England, Slovakia, Greece, New Zealand, TABLE VII. COUNTRIES WITH HIG H AUTHORING BURST IN THE NETWORK America, Japan, Ireland, Pakis tan, Belgium, Oman, Finland, OF CO -AUTHORS ’ COUNTRIES Serbia, China, Italy, Libya, Azerbaijan , Arabic UAE, Iran, Row Burst Burst Waiting France, Ukraine, Switzerland, Turkey and Russia , whereas Author Burst Begin End Span Time cluster eccentric connectivity index, in Cluster 6, is likely to be the 1 France 5.73 2002 2004 3 0 4 primary focus of collaborations between Croatia, Spain and 2 Malaysia 5.64 2010 2011 2 4 3 Romania. 3 America 4.21 2003 2004 2 0 4 4 Thailand 3.45 2008 2011 4 0 5 5 Netherlands 3.44 2008 2011 4 6 5

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