Saturday, 30 September 2017

Qualitative and quantitative analysis of solar hydrogen generation literature from 2001 to 2014


Scientometrics. 2015; 105(2): 759–771.
Published online 2015 Sep 9. doi:  10.1007/s11192-015-1730-3
PMCID: PMC4653236

Qualitative and quantitative analysis of solar hydrogen generation literature from 2001 to 2014


hydrogen generation is one of the new topics in the field of renewable
energy. Recently, the rate of investigation about hydrogen generation is
growing dramatically in many countries. Many studies have been done
about hydrogen generation from natural resources such as wind, solar,
coal etc. In this work we evaluated global scientific production of
solar hydrogen generation papers from 2001 to 2014 in any journal of all
the subject categories of the Science Citation Index compiled by
Institute for Scientific Information (ISI), Philadelphia, USA. Solar
hydrogen generation was used as keywords to search the parts of titles,
abstracts, or keywords. The published output analysis showed that
hydrogen generation from the sun research steadily increased over the
past 14 years and the annual paper production in 2013 was about three
times 2010-paper production. The number of papers considered in this
research is 141 which have been published from 2001 to this date. There
are clear distinctions among author keywords used in publications from
the five most high-publishing countries such as USA, China, Australia,
Germany and India in solar hydrogen studies. In order to evaluate this
work quantitative and qualitative analysis methods were used to the
development of global scientific production in a specific research
field. The analytical results eventually provide several key findings
and consider the overview hydrogen production according to the solar
hydrogen generation.

Electronic supplementary material

online version of this article (doi:10.1007/s11192-015-1730-3) contains
supplementary material, which is available to authorized users.
Keywords: Solar hydrogen generation, Hydrogen generation, Water splitting, Hydrogen literature


Today’s energy shortage and environment pollution are the two issues that we face in this century (Maghami et al. 2014, 2015), and due to these reasons, the industry for producing renewable energy is growing (Kotler 2011; Motlagh et al. 2015). One of the important methods of energy generations from renewable energies is solar hydrogen (Momirlan and Veziroglu 2002; Bak et al. 2002; Barbir 2005; Momirlan and Veziroglu 2005; Zhang et al. 2007; Sherif et al. 2005; Veziroglu 2008; Nadal and Barbir 1996; El-Bassuoni et al. 1982; Sopian et al. 1996).
As a renewable and clean source, solar energy has gained significant
attention in recent years for the high demand for low energy at a
competitive cost and with zero emissions (Nadal and Barbir 1996; Dincer 2011; Eriksson et al. 2006; Barbir 2012; Fakioğlu et al. 2004).
Since solar energy is inherently variable and intermittent, one of the
main obstacles to their widespread use in providing reliable electric
power is the requirement to store the electrical energy (Gorensek and
Forsberg 2009; Xiong et al. 2002).
hydrogen for energy storage system is an attractive option which is
surplus electric power that is obtained from a photovoltaic panel that
moves to an electrolyser to generate hydrogen stored by water splitting
and then, the stored hydrogen gas is supplied to a fuel cell during
times of low or no sunlight to compensate the supply shortfalls (Linkous
2001; Ghosh et al. 2003; Satyapal et al. 2007; Winter 1987).
research has been done on the different components of solar-hydrogen
system for RAPS, namely the solar PV panel, electrolyser, hydrogen
storage and fuel cell (Bak et al. 2002; Larminie et al. 2003; Dicks 1996).
Shabaniet and Andrews considered the PEM fuel cells in experimental
investigation to supply heat and power in PAPS. The economic advantages
of using the fuel cell heat to improve the LPG hot water system over a
30-year appraisal period is estimated to be about 15 % of the total
capital cost of the solar hydrogen system. John Andrews and Xin Xu Dou
studied about designing a control unit for a solar-hydrogen system for
remote area power supply in 2010 in Australia, and they found that all
requirements started earlier will be carried into the simulation
(Matlab) to establish the best control algorithms. When they designed
the optimum control, system was tested in computer. The experience
system was designed to measured real performance.
overview of experimental and demonstration systems are described in the
literature. However, there is still a need for more work on the general
control unit for these systems as well as reducing the total cost of the
system, extending the lifespan of components, and safety assurance.
Some research investigations have been done on design and test of
preferred options for splitting the Photovoltaic output between final
load and electrolyser as needed by the instantaneous system conditions,
as well as achieve high power transmission efficiency to the combined
final load and electrolyser. Figure 1
shows that solar cells absorb light from the sun. Then, they transfer
it to the electrolyzer in order to split water into hydrogen and oxygen
(van de Krol et al. 2008).
Fig. 1
Solar cell inserts electric to the electrolyzer
this paper, we consider solar hydrogen literature. Since, hydrogen is a
relatively broad term, it can refer to a number of different
technologies, processes, and methods. It has many applications related
to energy, smart grid, energy management, energy policy,
telecommunications, and business. For this reason, hydrogen applications
can be the foundation for many location-enabled services that rely on
analysis, visualization and dissemination of results for collaborative
decision-making. The aims of this paper is to analysis qualities and
quantities of the researches done during the last two decade.

Methodology and materials

documents used in this study were accessed from the database of the
Science Citation Index (SCI), obtained by subscription from the ISI, Web
of Science, Philadelphia, PA, USA. In this study, we only focus on
papers published after 2001, because there was less data regarding solar
hydrogen before that year. To shed the light on solar hydrogen trends
and contributions, quantitative analysis and qualitative analysis are
conducted in this research.

Quantitative analysis

the quantitative analysis, the SCI are systematically searched for
solar hydrogen-related materials published from 2001 to April 2014.
Selected documents included ‘‘Solar hydrogen generation’’ in the title,
abstract, or keywords. Analyzed parameters included authorship, patterns
of international collaboration, journal, language, document type,
research address, number of times cited, and reprint author’s address.
Citation analysis was based primarily on the impact factor as defined by
the journal citation reports (JCR) and on citations per publications
(CPP), which are used to assess the impact of a journal relative to the
entire field. It is defined as the ratio of the number of citations the
publication has received to since it is published.

Qualitative analysis

qualitative analysis the historical method was used. The historical
method proposes that historical phenomena can be rich and complex; we
can gain a better understanding by reviewing and investigating the
times, places and contexts in which events occur and develop. The
historical method was employed in investigating the initiation and
development of solar hydrogen as documented in publications in the SCI
from 2001 to April 2014. For a longitudinal literature review, we
employed historical review method to explore solar hydrogen
technological trend. Based on this review, we forecast possible future

Result and discussion

Number of publication and citation among year

According to the data obtained from ISI Web of Knowledge as presented in Fig. 2, it shows the number of publications about solar hydrogen generation in a period of 15 years. From the Fig. 2,
it is concluded that the research about this topic have just been
published from 2000. Therefore, it is observed that research in solar
hydrogen is extensively new topic. In addition, there were fewer than
six paper published before 2006 and only after 2008 this research became
a hot topic among researchers. Obviously, in 2013 there was rapid
increase in number of publications and citations. Although in 2008 the
number of publications was fewer than 2007, however, the citation trend
shown in Fig. 3
indicates that the number of citations is very close to the one in
2007. Thus, the promising future of solar hydrogen is guaranteed.
Fig. 2
Number of paper published among year is displays
Fig. 3
Number of citation among year is displays
total citation count was obtained from SCI, web of science, on April
20, 2014. When the SCI search process for this study was conducted, the
total number of times that a particular paper had been cited by all
journals listed in the database was shown. The title of the most highly
cited paper published in this area since 2001 is “Estimating
Photo-electrochemical hydrogen generation”. Materials-related aspects by
Bak, T, received by International Journal of Hydrogen Energy 2002,
which has been cited for 549 times. Among the top ten most cited papers,
the USA contributed 4 of them, followed by Australia, which produced
two articles and China, Armenia, Switzerland and Israel with one
articles each. It is worth mentioning that papers related to Energy had a
relatively higher number of citations than many other scientific
fields. Nevertheless, there still exist a biasness on citation analysis
due to differences of the publication year. It must be pointed out that
the number of citations in single article was highly correlated with the
length of time since its publication. As it can be seen in Fig. 3,
the average number of times that the paper receives citations increases
as the time goes on since its publication. Therefore, average number of
citation per year was used to compare the papers in different years.
From 2005 to 2014, the annual number of Citation articles according to Fig. 4 the scatter plot was growing at a stable rate. The fit produced a high determination coefficient from the collected data (R2 = 0.8717). The best fit to forecast solar hydrogen generation was found to be:
y = 37.868x - 75861
Where y is the article number and x
is the number of years since 2001. Extrapolating from the model, the
number of articles about forest ecology in the following years could be

Fig. 4
Scatter plot for solar hydrogen citation are displays

Distribution by source titles, research area and web of science categories

According to Table 1,
most of the papers in this field are published in International Journal
of Hydrogen Energy, which has ranked 16 in categories of energy fuel,
with 32 papers. Following by abstracts the best publisher in field is
American Chemical Society with nine papers. According to the fourth
column of Table 1, Energy fuel with 73 papers, followed by Chemistry with 70 and electrochemistry with 41 are the three best categories.
Table 1
Distribution by source titles and Research area
to distribution by web of science categories, Energy fuel, chemistry,
and electrochemistry are the three categories, which publish most of the
papers, followed by chemistry and material. Figure 5, shows more than 70 % of those papers published in those three categories.
Fig. 5
Distribution by web of science categories

Top ten papers in solar hydrogen generation

The most frequently cited articles for the period between 2003 and 2014 are presented in Table 2.
Five of the most frequently cited articles were published in
International Journal of Hydrogen Energy. Six of the most frequently
cited articles (among them the top six listings) originated in the USA
and Australia, and one each in, China, Armenia, Switzerland, and Israel
respectively. The two articles with the most citations (549 and 135)
come from International Journal of Hydrogen Energy and Nano letter. An
interesting aspect, presented as the fourth column in Table 2,
is the average number of citations per year (AC). Although this
observation is not consistent, it appears that the number of citations
per year tends to increase with the number of years since publication.
Pointing to a possible snowball effect when it comes to the acceptance
of novel research results published papers involved international
collaborations. A summary of the ten most frequently cited articles
revealed that six papers originated in the United States, and four were
published in International Journal of Hydrogen Energy, which has one of
the highest impact factors in the category of energy. The three journals
with the most articles in this category were Solar Energy, Energy and
Environmental Science and Journal of Power Sources.
Table 2
Top high citation papers in field solar hydrogen generation

Distribution by document type and language

majority of publications on solar hydrogen generation research is done
in English. One interesting finding is the increase in solar hydrogen
generation research since 2010; it is clear that Solar Hydrogen
Generation or Solar Hydrogen Power study is becoming ever more important
around world. According to Fig. 6,
it is clear more than 97 (68 %) of papers published is articles,
followed by 35 (24.8 %) proceedings paper, abstract with 6 %, amd review
with 2 %.
Fig. 6
Type of document in ISI web of knowledge

Distribution by countries and organization

Table 3
shows USA is at the top with 42 (20.20 %), followed by China, with 16
(15.33 %). Australia ranks third, with 13 (6.13 %). Germany, India,
Japan, Spain, England, South Korea and Switzerland, were also among the
top ten countries publishing solar hydrogen generation articles. Listing
publications by organization name, in third column Table 3,
shows that the United States Department Of Energy Doe With 10 articles,
University of California System with seven articles, at the top
institution, followed by Chinese Academy Of Sciences, Royal Melbourne
Institute Of Technology RMIT, are the top four solar hydrogen research
institutions that have published the most articles on solar hydrogen
power during 2001–2014.
Table 3
Distribution by country/territory and institution name

Distribution by author, frequency author keyword and funding agencies

According to the Table 4,
there are 67 authors in the world who participated in publications
related to solar hydrogen generation research area. The first 10 authors
are listed in Table 4
with the number of publication in this area. Prof, Roeb and Sattler
with six publication in solar hydrogen generation from Germany has most
of the papers, following by Andrews from Australia with five papers.
Behind them kanmani, Li Y and Licht are the five top author in this
Table 4
Top ten author and funding agencies in solar hydrogen generation
In the third column of Table 4,
it is shown that the top funding agencies which funded the
investigations on solar hydrogen generation. National Natural Science
Foundation Of China with 8 papers is the first among funding agencies
followed by NSF with five paper is ranked second, and Natural Basic
Science Program China with three papers are the top three funding
agencies in field of solar hydrogen.
In Table 5,
author keywords that appeared in the articles from 2001 to 2014 were
counted with intervals of 5 years. Among all 107-author keywords used,
72 (71 %) keywords appeared only once, 23 (21 %) keywords were used
twice, and 8 (7 %) keywords appeared three times. The large number of
one-time-used keywords probably indicates a lack of continuity in
research and a wide disparity in research focuses. The most frequently
used keyword for all periods was “Solar hydrogen” as it was also a
keyword used in this research. During the entire study period, Hydrogen,
Solar energy and Water splitting are always the most frequently used
author keywords, which indicates that these title are invariable
hotspots in the field of solar hydrogen production research.
Furthermore, it is worth noticing that limited research has been done
before on Photocatalysis, Hydrogen production, and PEM electrolyser.
However articles on these aspects have obviously increased in recent
years. The number of papers and percentage of which author keywords
including solar hydrogen and hydrogen etc.
Table 5
Frequency keyword by author
indicates that ‘information systems attracted more and more attention
during the past 14 years, indicating that these words may be a potential
new focus in the future. On the contrary, it is surprising to find that
there are several popular titles in the past such as Photocatalysis
etc. that are becoming gradually less significant as noted during our
10-year study period.

Review the first 10 top papers in field of solar hydrogen generation

to Table 6 (see Online Supplement), there are four papers that try to
improve efficiency of photo-electrochemical cells by using different
material type, three researches on control current and voltage to get
maximum power and other papers review the researches done in this field.
The result of these 10 top paper shows that in order to improve
efficiency of the generation, materials and control the losses on the
process must be up to dated. One of the interesting paper, which
published in 2008, consider solar hydrogen generation for vehicles with
total citation 56 and average citation eight for each year, which
published in USA and number of citation each year dramatically increase.
In first column Table 6 (see Online Supplement), it is show that 6
paper of 10 top paper published after 2006, in other word, it is clear
how this topic become hot topic in this area.


this work on solar hydrogen -related papers dealing with the SCI, we
obtained some significant points on the global research performance
throughout the period from 2001 to 2014. In total, 4681 articles were
published in 1918 journals listed in 202 subject categories established
by ISI. The solar hydrogen generation presented an upward trend as the
paper production increased exponentially in the last 14 years, and the
annual paper production in 2013 was about three times that of the paper
production in 2010. As the flagship journal of the solar hydrogen
generation related field, International Journal of Hydrogen Energy
published the most articles. Approximately 22 % of the articles that
refer to solar hydrogen generation reside in the 10 core journals,
whereby the remainder resides in the other 1908 journals. With the study
of national research publications in the last 15 years, the increasing
trend in the number of countries worldwide participating in this
research can be easily observed. To a certain extent, large numbers of
research papers from a country are correlated with the high activity and
academic level of the country. It was notable that USA and China,
contributing the most independent and international collaborative
articles, had the most frequent international partners. Articles with
international co-authorship, shows higher visibility than others over
the years. The use of several author keywords such as ‘solar hydrogen,
‘hydrogen ‘and ‘solar energy dramatically increased since 2007, which
became the focus in the last few years, and might be a new research
direction in the future. There are clear distinctions among author
keywords used in publications from the five most productive countries in
solar hydrogen research. Quantitative and qualitative analysis used to
the development of global scientific production in a specific research
field. As solar hydrogen generation has always been thought to be widely
useful to energy saving, more efforts should be taken to further
studies in these fields.

Electronic supplementary material


authors gratefully acknowledge the financial support for this work that
provided by University Putra Malaysia. I wish to thank Dr. Mahmmod
Danaei for comments that helped to improve the manuscript, and for
helping to search the literature.


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  • Wang H, et al. Self-biased solar-microbial device for sustainable hydrogen generation. ACS Nano. 2013;7(10):8728–8735. doi: 10.1021/nn403082m. [PubMed] [Cross Ref]
  • Winter C-J. Hydrogen energy—expected engineering breakthroughs. International Journal of Hydrogen Energy. 1987;12(8):521–546. doi: 10.1016/0360-3199(87)90012-7. [Cross Ref]
  • Xiong
    L, Kannan A, Manthiram A. Pt–M (M = Fe Co, Ni and Cu) electrocatalysts
    synthesized by an aqueous route for proton exchange membrane fuel cells.
    Electrochemistry Communications. 2002;4(11):898–903. doi: 10.1016/S1388-2481(02)00485-X. [Cross Ref]
  • Z’graggen
    A, et al. Hydrogen production by steam-gasification of petroleum coke
    using concentrated solar power—II Reactor design, testing, and modeling.
    International Journal of Hydrogen Energy. 2006;31(6):797–811. doi: 10.1016/j.ijhydene.2005.06.011. [Cross Ref]
  • Z’graggen
    A, et al. Hydrogen production by steam-gasification of petroleum coke
    using concentrated solar power—III. Reactor experimentation with slurry
    feeding. International Journal of Hydrogen Energy. 2007;32(8):992–996. doi: 10.1016/j.ijhydene.2006.10.001. [Cross Ref]
  • Zhang Y-HP, et al. High-yield hydrogen production from starch and water by a synthetic enzymatic pathway. PLoS ONE. 2007;2(5):e456. doi: 10.1371/journal.pone.0000456. [PMC free article] [PubMed] [Cross Ref]

Qualitative and quantitative analysis of solar hydrogen generation literature from 2001 to 2014

Friday, 29 September 2017

Search Engine Optimization: How to Attract More Visitors to Your Repository - bepress

Search Engine Optimization: How to Attract More Visitors to Your Repository

What is “Search Engine Optimization”?

Generally speaking, “Search Engine
Optimization” (SEO) focuses on getting a website’s content to rank
highly in search engines, such as Google™ and Bing™. Search engines are a
major source of traffic to Digital Commons repositories, so getting
your repository content listed at the top of the search results is
guaranteed to have a significant impact on its visibility and

SEO & Digital Commons: Setting You Up for Success
Having a Digital Commons repository automatically puts you ahead in the SEO game:

  • Bepress works closely with specialized search engines such as Google
    Scholar™ to ensure widespread and accurate coverage of Digital Commons
  • Sitemap XML files are automatically generated, providing a road map
    for search engines to find all the repository content. When new content
    is posted, Google is automatically notified, further increasing the rate
    at which new content gets discovered.
  • Digital Commons page titles are structured to be unique across the
    repository as well as informative—using terms to help search engines and
    individuals better assess page relevance. (Duplicate or non-informative
    titles can hinder the accurate and efficient indexing of content.)
  • Digital Commons repositories are kept up and running efficiently, minimizing search engine “crawl” errors.
  • SEO is not a one-time upgrade. For every release, bepress considers
    enhancements to keep all Digital Commons repositories current with the
    evolving recommendations of major search engines.
What Can I Do to Improve Ranking?
SEO is a complex field to navigate.
Bepress can steer you toward a number of best practices, highlighted in
the following pages, which you can follow to influence your repository’s

Link to Repository Content

Getting more links to your repository
from quality sites is probably your most powerful SEO tool.  Search
engines count the number of websites that link to yours, placing more
value on links deemed to be from very reputable or popular sites.

Who links to your repository now? You
can explore inbound links to your site using Google Analytics™, which
is implemented for each Digital Commons repository (
An Overview of Digital Commons Reports). As
interesting as it is to see which sites link to yours, it’s also useful
to discover which sites don’t link to your site but should.

What you can do:  Start a campaign to get more links!

  • Link to the repository from your institution’s homepage, the library’s website, and other relevant pages.
     For example, department web pages should link to any corresponding
    publications (series, book galleries, etc.) in the repository.
  • Add RSS feeds from your repository to the library or a departmental website.
  • Encourage faculty to link to their articles from personal websites, blogs, related societies’ web pages, and social media sites like Facebook.
  • Link to repository content from related Wikipedia pages,
    as appropriate. Use the “edit” links on the Wikipedia page to suggest
    your repository content as a reference or further reading. And, use the
    Wikipedia citation templates to enter an article as a citation:
  • Web Directories:
    Web directories are human-edited, categorical listings of websites.
    Search engines consider a listing here as a positive rating factor.
    Consider submitting your repository to Open Directory Project (DMOZ),
    your journals to the Directory of Open Access Journals (DOAJ), and
    subject-based content to relevant directories as you discover them.
Link Formatting Guidelines
The text of a link should be descriptive:

  • Use the title of an article, or include highly relevant keywords
  • Include the trailing “/” and exclude “index.html” or other extra material

    Example: <a href=””>Digital Commons</a>
  • Avoid creating links with uninformative text, such as “click here.”

Use Descriptive Page Titles

In most browsers, page titles appear
at the top of the window when viewing a page. Search engines use these
titles to help evaluate the page’s subject matter, and typically display
the titles prominently as links on the results page.  So a well-worded
page title helps potential visitors discover your content via searches,
and increases the likelihood that they will select it from the list of
search results.

What you can do:

  • Review the page title for the
    repository homepage and any publication homepages. If a title is too
    generic to be meaningful to search engines or potential visitors, use
    Descriptive Page Title field on the Configuration screen to improve results.
  • Use relevant keywords and popular
    search terms, and limit titles to less than 150 characters (only the
    first 70 characters or so are displayed on the search results page).
Example Journal Name:   Green

Example Descriptive Page Title:  Green: The Economics of Recycling Journal

Improve Search Results Snippets

Do a search in Google and look at the
results page. Below each link is a brief description of the found page,
called a “snippet.” These snippets are important because readers rely
on them to make decisions about which links to click.

Search engines get snippets in a
number of ways:  from an Open Directory entry that stores information
about each site, from a meta-description tag in the HTML source of the
page, or culled from the information on the page itself.

What you can do:

  • If you are unsatisfied with snippets used for the repository, communities, or publications, suggest your own meta-description using the Search Description option
    on the Configuration screen. The description should accurately
    represent the content and “market” it via the search results page. Only
    the first 155 characters or so appear in the snippet, so short phrases
    can be more effective than full sentences in some cases. Note that the
    meta-description tag is just a suggestion; there is no guarantee it will
    be used.
  • Make sure all posted documents have an abstract
    because Digital Commons articles are automatically set up to use the
    abstract as the meta-description. Enter a short description, including
    file type for images and media files. Because abstracts also appear on
    the article’s web page, be sure to use terms from the title and full
    text to help articles rank higher in related queries.
If you have publications where
numerous articles are missing abstracts, it’s worth the time to add
abstracts to them. Refer to our 
batch upload and revision information if there are numerous articles to revise. Please contact bepress Consulting Services at or phone (510) 665-1200, option 2 with any questions about batch revision.

Best Practices for Repository Upkeep

Keep the Repository “Alive”!
Large, active repositories can convey
more perceived authority to search engines, thereby boosting the
ranking for all of the repository contents. This generates more traffic,
which also continues to improve ranking.  It’s a positive cycle—so
keep posting content!

Find creative ways to update your homepage and showcase repository content.
For example, feature a journal of the month, an upcoming event, or a
special gallery on your homepage to give the featured content a boost.

Choose Publication Names and URLs with SEO in Mind
Pages tend to rank higher when the
URLs contain the search terms. Also, most people examine the URL in
search results, to help decide whether to click a link. So, when
creating new publications,
choose descriptive terms for the URL, such as “ecology” instead of “ecol.”   

Monitor Your Efforts
Using tools like Google Analytics™
and Digital Commons reports, you can monitor your repository’s
performance. See the resources below for more information. You may also
schedule an annual review of these elements with your IR team.

Related Resources

Search Engine Optimization: How to Attract More Visitors to Your Repository - bepress

Thursday, 28 September 2017

Research Bulletin (Vol.3, Issue no.3)


Feature Article — Optimizing Research Articles for Search Engines

Internet search engines are commonly used to find research
articles. To increase the discoverability and impact of their research,
academics should make their articles more likely to be found on search
engines and read by the academic community. Optimizing your articles for
search engines not only enables them to be indexed by the engines but
also ranked higher in the search results, which helps to enhance the
visibility and citation rate of the articles.

The importance of search engine optimization (SEO) for academic visibility

SEO helps to enhance the visibility, accessibility and citability of
your publications by making them more discoverable online. More
specifically, in the context of academic publishing, academic search
engine optimization (ASEO) has become an important strategy for making
your research accessible by fellow researchers. ASEO is defined as ‘the
creation, publication, and modification of scholarly literature in a way
that makes it easier for academic search engines to both crawl it and
index it.’ (Beel, Gipp, & Wilde, 2010). With optimization of
articles in response to different search engines, researchers can
increase their usage and expand their readership, and so enhance the
overall impact of their research output.

How do you make your articles more discoverable?

Web search engines usually index all texts on websites. For searching
relevant documents, they detect how often a search term or keyword
occurs in the documents. In general, the more frequent the search term
occurs and the more it occurs in a heavily weighted document field, the
more a document is considered relevant (Beel et al., 2010).

Academic search engines have different ranking algorithms for displaying
the search results. Google Scholar, for example, focuses heavily on
document titles, meaning that a search term appearing in the title of a
document is more likely to increase your article’s ranking and
visibility in a search result than its appearance in the body of an
article. Also, academic search engines consider factors such as citation
count, authors’ names, and publication dates. Strategies are needed to
maximize your article’s searchability. With reference to the literature
on SEO (e.g. Beel et al., 2010; Elsevier Biggerbrains, 2012; SAGE
Publishing, n.d.; Shafer, n.d.; Wiley-Blackwell Author Services, n.d.),
various ways in which you may optimize your articles with search engines
on different criteria are suggested below.

1. Keywords:

Choose a few (but not too
many) relevant keywords or keyword phrases for your articles. Consider
using tools to help in making this decision, such as Google Trends,
Google Insights or Google AdWords, which help you to test the popularity
of the chosen keywords in search results. If the choices are too
popular or too general (i.e. yielding a large amount of search results),
you may choose or add another keyword with less competition.

Use keywords consistent with your field. However, you should also avoid
keyword stuffing — mechanical and excessive repetition of certain
keywords — in writing your abstracts, because search engines may
consequently remove your articles from the database.

2. Title:

Keep your title short and
relevant. Try to use one or more keywords in the title which ideally
describes your article in a concise manner.


Put essential keywords in the
first two or three sentences of your abstract, which may be the only
content that appears in search engines. Repeat the keywords a few times,
or use synonyms to highlight the gist of your research in your


Citations are a crucially
factor for the indexing and ranking of articles by academic search
engines, especially Google Scholars. Be sure to reference your own and
any co-authors’ previous relevant publications in your article,
providing links where those references can be downloaded as this helps
both the engines and readers to locate the full text. Refer to the names
and initials of authors consistently so that search engines can perform
identifications precisely.

5.Formats of graphics:

Make sure the tables and
figures in your papers are machine readable. Vector graphics (e.g.
images in .svg, .ai, .eps, and .ps formats) containing font-based text
are preferable to image-based graphics, such as .tiff, .bmp, .jpeg,
.png, .pdf, .gif and .psd, which cannot be indexed by search engines.


When choosing or considering
journal submissions, authors should also consult the journal’s or
publisher’s policies on allowing authors themselves to share and
publicize their own work online. Open access articles have greater
visibility than journals that can be obtained only through purchase or

7.Social networks:

After your article is published, share it in your academic and social networks on social platforms such as


• Linkedin

• Facebook

• Twitter

• Mendeley

• Your academic institution's website or repository

• Your website or any website that you contribute to

• Wikipedia (as a reference link)

Further details and resources about SEO are available in the Research Resources section of this issue of the Research Bulletin.


Beel, J., Gipp, B., & Wilde,
E. (2010). Academic search engine optimization (ASEO):
Optimizing scholarly literature for Google Scholar and
Co. Journal of Scholarly Publishing,
41(2), 176–190.

Elsevier Biggerbrains. (2012). Get found — optimize your
research articles for search engines. Retrieved from

SAGE Publishing. (n.d.).
Help readers
find your article.
Retrieved from
Shafer, S. (n.d.). SEO for authors: A how-to guide.
Retrieved from

Wiley-Blackwell Author Services. (n.d.). Writing for
SEO. Retrieved from

Research Bulletin (Vol.3, Issue no.3)

Interview with MDPI: Lessons Learned in more than 20 Years of Open Access Publishing - The Scholarly Kitchen


Among various highlights of this year’s SSP Annual Meeting, I unearthed a few well-kept mysteries about MDPI,
Swiss-based open-access (OA) journal publisher. Launched 21 years ago
by Dr. Shu-Kun Lin, a chemist who graduated from ETH Zurich, MDPI
started off as something very different than a publishing house. Despite
cycles of controversy,
MDPI continues to grow, now employing more than 900 people across seven
offices. Their CEO, Dr. Franck Vazquez, joined MDPI just three years
ago, after an academic career in life and health sciences. Vazquez,
recently appointed to the
OASPA board, met with me between SSP sessions to share their story.

 past future

Tell me about your journals, what disciplines do they
address? Am I correct in my understanding that they are all gold OA

MDPI launched as a repository for rare chemical samples and, from the
start, sustainability was a main consideration. Many of our journals
remain close to these roots, including Molecules (our first journal, launched in 1996), Sustainability, Molbank, the International Journal of Molecular Sciences, Water, and Energies.

We currently publish 177 journals across all major research
disciplines. Our journals are fully open access and articles distributed
under a CC BY license with only a few exceptions. Apart from our most
recent titles, which are not yet eligible, all of our journals (152)
have been accepted by DOAJ and more than 80% of the 110,000 articles
published so far are available in Web of Science (SCIE, SSCI, AHCI, and
ESCI). To date, 92 MDPI journals are covered by Web of Science, 73 by
Scopus and 41 by PubMed. Further information is available in our 2016 annual report.

How have the business models for MDPI evolved over the years?

MDPI has always aimed to make papers available for free. We did this
before the term “open access” was introduced, although the values we
have held from the start match well with the aspirations of open access.
The chemical samples project was
started by Dr. Lin and is still running. It collects and stores rare
chemicals that are often difficult to synthesize, and makes them
available to researchers and industry users. It covers costs by charging
a fee to send out samples, and this income was initially used to cover
publication costs. The first journal Molecules was launched as a
free-to-read electronic journal, encouraging authors to deposit
chemical samples, instead of charging publishing fees. Additional
funding came from conferences and donor organizations, along with a few
authors who voluntarily paid APCs. MDPI briefly experimented with a
subscription model in 2005 before switching to an APC-based model in
2006, which allowed us to separate the publishing arm from the sample
preservation activities. This meant we could further expand and
professionalize the publishing service.

For a short-lived period, I understand MDPI moved to a subscription model?

This was indeed a short-lived model put in place while MDPI sought
ways to be financially sustainable. The model was quickly abandoned and
an APC model was put in place for all journals. The editorials by Dr. Lin in 2005 and with colleagues in 2006 provide an historical perspective on this experience.

MDPI was briefly included on Jeffrey Beall’s list of predatory publishers, and then later removed. What lessons were learned from that experience?

In 2014, we responded point-by-point to Jeffrey Beall’s criticism and
made formal appeals, after which MDPI was removed from the list in
2015. I believe we successfully demonstrated that MDPI does not breach
any of the criteria set by Jeffrey Beall for so-called “potential,
possible or probable predatory scholarly open-access publishers”. While
we understand the motivation behind maintaining a blacklist, we believe
that whitelists such as Web of Science, PubMed, Ei Compendex, Scopus,
and DOAJ, which transparently evaluate journals and publishers based on a
set of specific standards, are more helpful to scholars. Following the
criticism by Jeffrey Beall, we received many messages of support from
authors, editorial board members, and reviewers, confirming their trust
in our work. This has strengthened our confidence that we provide a
valuable service. Our editorial procedures were checked and validated by
OASPA. One change we made during this period was to highlight our
procedures and standards more prominently on our website.

So, it sounds like you took a more grassroots approach in your response, rather than launching a big marketing campaign.

We provided public statements whenever we were directly criticized,
but we chose to focus our attention and energy on developing our
journals and serving the scientific community, rather than engaging in
large amounts of corporate communication. We received a great deal of
support in direct communication with authors, reviewers and editorial
board members. For those who had read Jeffrey Beall’s comments, we were
able to persuade them of our integrity when presented with the facts. We
launched an institutional open access program in 2013 and since then
established agreements with over 240 university libraries. We regularly
conduct surveys to receive direct feedback from authors, reviewers and
external editors, and listen closely to feedback from the community.

Tell me about your approach to peer review and the various models you employ.

Peer review is central to scholarly publishing. Most of our journals
operate single blind peer review and 13 of them offer optional open peer
review (reviews are published with the paper and the reviewers can
optionally sign their review reports). We operate double-blind peer
review in fields where it is the norm. We leave the decision on the peer
review model, including open peer review, to our Editors-in-Chief.

When MDPI launched 20 years ago, where did Dr. Lin see OA publishing headed?

In 1996, the term “open access” had not yet been introduced, and this
mode of publishing was called “free to read electronic publication.”
MDPI’s model for online publishing in the chemistry field was
self-sustainable, but larger operations required an APC based model. Dr.
Lin took part in major initiatives related to open access and was
convinced by its long-term viability. Most of the journals listed on the
Budapest Open Access Initiative website at that time were MDPI

I’m told MDPI has demonstrated year-on-year growth for each
of the past five years. To what do you attribute this healthy progress?
Is this rate of growth is sustainable?

Yes, this is correct, the exact figures are available in our 2016
annual report. This year we will likely grow 40% and publish around
32,000 peer reviewed articles, even though our rejection rates have
increased from 52% to over 58% in the past two years. We are dedicated
to our mission of providing an excellent service and according to our
survey results over 98% of authors are satisfied with the work we do and
would publish with us again. Indeed, we see a high number of returning
authors. Our editors strive to ensure that the development of MDPI is
sustainable. If we keep our focus and remain flexible to meet the
rapidly-changing needs of the scholarly community at large, I am
confident that MDPI will continue to expand.

What would be your advice for new OA publishers? What about policymakers and/or funders?

The only advice we have, which we also apply to ourselves, is to
focus on the best interests of scientists, science in general, and
society at large. Our world is changing quickly — much faster than
scholarly publishing. We have a responsibility to contribute by ensuring
fairness, openness and sustainability in academic research and academic

MDPI evolved from a chemical sample repository to a large-scale publishing house. Where do you see MDPI evolving in the future?

Dr. Lin and myself started our careers in science and we know that
the publishing process can sometimes be burdensome. Our objective for
the future is to reduce the time spent by authors on administrative
tasks (reformatting references, making layout corrections, etc.) and
aspects of scientific communication that can easily be handled by
publishers. We want to provide convenience to our editorial board
members, reviewers and authors when they interact with us and our
systems. This will allow us to make efficiencies in the editorial
process, in turn allowing more time for scholars to pursue their
research, participate in discussions and exchanges, and build

Open access is all about fairness and sustainability. We believe that
MDPI can contribute further by maintaining a healthy competition
between publishers and ensure that publishing costs are fair. Research
funds should be used for research, not to cover expensive subscription

In the long run, we aim to anchor MDPI in research communities. We recently developed and launched the preprint platform Preprints, revamped our free-to-use conference hosting platform Sciforum, and are working on other projects, such as Scilit,
our bibliographic database, which contains 96 million scientific
article records and is updated daily from Crossref and other sources.
Our projects provide pre- and post-publication services, in addition to
our standard publishing service. The overall aim is to help researchers
disseminate their results effectively and provide new tools that
facilitate their research activities and communication.

Lettie Y. Conrad

Lettie Y. Conrad

Lettie Y. Conrad is a
publishing and product development consultant, working as a senior
associate with Maverick Publishing Specialists, as well as with a
portfolio of independent global clients. When she's not bringing a
user-centered approach to scholarly content discovery and accessibility,
Lettie serves as North American Editor for Learned Publishing and is a
part-time information science doctoral student via a remote program at
Queensland University of Technology.
View All Posts by Lettie Y. Conrad


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Interview with MDPI: Lessons Learned in more than 20 Years of Open Access Publishing - The Scholarly Kitchen