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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>EU-Brazil Open Data and Cloud Computing e-Infrastructure for Biodiversity</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Rafael Amaral</string-name>
          <email>rafaelbba@ic.uff.br</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rosa Badia</string-name>
          <email>rosa.m.badia@bsc.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ignacio Blanquer</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Leonardo Candela</string-name>
          <email>candela@isti.cnr.it</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Donatella Castelli</string-name>
          <email>castelli@isti.cnr.it</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Renato de Giovannik</string-name>
          <email>renato@cria.org.br</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Willian A. Gray</string-name>
          <email>W.A.Gray@cs.cardiff.ac.uk</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andrew Jones</string-name>
          <email>Andrew.C.Jones@cs.cardiff.ac.uk</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Daniele Lezzi</string-name>
          <email>daniele.lezzi@bsc.es</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pasquale Pagano</string-name>
          <email>pagano@isti.cnr.it</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vanderlei Perez-Canhosk</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Francisco Quevedo</string-name>
          <email>F.Quevedo.Fernandez@cs.cardiff.ac.uk</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Roger Rafanell</string-name>
          <email>roger.rafanell@bsc.es</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vinod Rebello</string-name>
          <email>vinod@ic.uff.br</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Erik Torres</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Artificial Intelligence Research Institute (IIIA), Spanish National Research Council</institution>
          ,
          <addr-line>CSIC</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Computer Sciences, Barcelona Supercomputing Center</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Institute of Instrumentation for Molecular Imaging (I3M), Universitat Polite`cnica de Vale`ncia</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Istituto di Scienza e Tecnologie dell'Informazione (ISTI)</institution>
          ,
          <addr-line>Consiglio Nazionale delle Ricerche, CNR</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>-EUBrazilOpenBio is a collaborative initiative addressing strategic barriers in biodiversity research by integrating open access data and user-friendly tools widely available in Brazil and Europe. The project deploys the EU-Brazil cloudbased e-infrastructure that allows the sharing of hardware, software and data on-demand. This e-Infrastructure provides access to several integrated services and resources to seamlessly aggregate taxonomic, biodiversity and climate data, used by processing services implementing checklist cross-mapping and ecological niche modelling. The concept of Virtual Research Environments is used to provide the users with a single entry point to processing and data resources. This article describes the architecture, demonstration use cases and initial experimental results.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Keywords—Biodiversity, Data Infrastructure, Virtual Research
Environments, Cloud, Taxonomy, Ecological niche modelling</p>
    </sec>
    <sec id="sec-2">
      <title>I. INTRODUCTION</title>
      <p>
        The EUBrazilOpenBio project [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] aims to build an
eInfrastructure for research in biodiversity by leveraging
primarily on resources (textual publications and datasets, maps,
taxonomies, tools, services, computing and storage
capabilities) provided by European and Brazilian e-Infrastructures
available through existing projects and initiatives.
Interoperation extends to all the infrastructure namely: hardware and
computing facilities (Cloud and Grid computing, Internet),
portals and platforms as well as the scientific data knowledge
infrastructure.
      </p>
      <sec id="sec-2-1">
        <title>A. State of the art</title>
        <p>
          One of the most pressing needs in the biodiversity domain
is the open and transparent access to data, tools and services.
To support the worldwide sharing of various collections of
biodiversity data [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ], a number of large scale initiatives have
occurred in recent years, either at global – e.g., GBIF [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ], OBIS
[
          <xref ref-type="bibr" rid="ref4">4</xref>
          ], VertNet [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ], Catalogue of Life [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] – or at a regional level
– e.g., speciesLink [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] and List of Species of the Brazilian
Flora [8]. Moreover, standards for data sharing have been
promoted by establishing appropriate interest groups, e.g., the
Biodiversity Information Standards (TDWG - the Taxonomic
Databases Working Group). Domain specific standards have
been developed addressing different interoperability aspects,
e.g., Darwin Core [
          <xref ref-type="bibr" rid="ref8">9</xref>
          ] and TAPIR [10] for distributed data
discovery. In spite of these efforts and initiatives, the biodiversity
domain is affected by a number of data sharing and reuse
problems. [11].
        </p>
        <p>New initiatives are creating global and web-based
infrastructures to store, share, produce, serve, annotate and improve
diverse types of species distribution information, such as the
Map of Life [12]. Such initiatives highlight how the integration
of disparate data types offers both new opportunities and new
challenges for species distribution modelling.</p>
        <p>The inherent complexity of using Distributed Computing
Infrastructures (DCIs) to adapt, deploy and run applications
and explore data sets have fostered the development of Science
gateways, which facilitate the scientists’ access to these tools,
and simplify the organization of data repositories and the
execution of experiments. There has been a concentrated effort
to create portals and general-purpose services to address such
issues. Portals and workflow engines such as Enginframe [13],
eScienceCentral [14], Moteur [15], or P-Grade [16], address
the problem of creating scientific workflows through individual
modules and wrapping legacy code. However, these general
approaches still require programming skills and background
awareness of the features of the underlying infrastructure.
Community portals, such as WeNMR [17], GriF [18], Galaxy1,
the Extreme Science and Engineering Discovery Environment
(XSEDE)2 or the gateway to nanotechnology online simulation
tools nanoHUB.org3 have developed customised solutions for
their user communities. Current project efforts in Europe like
SCI-BUS4 are defining a flexible framework for developing
science gateways based on the gUSE/WS-PGRADE portal
family. In the area of data management, the D4Science [19]
project has developed the gCube technology with a special
focus on management of big data and the concept of Virtual
Research Environments as its user interface. D4Science
supports biodiversity [20] and other user communities.</p>
      </sec>
      <sec id="sec-2-2">
        <title>B. Objective and motivation</title>
        <p>This article describes the achievements of the
EUBrazilOpenBio project in creating an integrated infrastructure
to assist research in biodiversity. The aim is to reduce the need
for researchers to access data from multiple sources for local
processing. Therefore, the project provides an access point to
necessary data, services and computing capabilities to support
research within the biodiversity community, demonstrated in
two representative use cases.</p>
        <p>The article is structured as follows. After this introduction,
a description of the use cases is provided (cf. Sec. II).
Section III describes the infrastructure of EUBrazilOpenBio
and Section IV details the implementation of the use cases.
Section V presents the conclusions.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>II. THE USE CASES AND REQUIREMENTS</title>
      <p>In order to demonstrate the benefits an infrastructure might
bring to the biodiversity informatics community, the project
uses the infrastructure facilities to realise two representative
use cases: the integration of taxonomies and production of
ecological niche models which help in estimating species
distributions. Although the requirements were elicited by
analysing these two use cases, the infrastructure was designed
and implemented with the aim of fulfilling the needs of a wider
range of biodiversity applications.</p>
      <p>In brief, the first use case aims at comparing two lists
of species with the objective of identifying missing and
incomplete entries. This process involves seamlessly accessing
and comparing different taxonomical information, and it is the
basis for enriching and improving existing regional and global
taxonomies. The second use case is a computational-intensive
problem consisting on constructing models that can be used
to estimate the suitability of the environmental conditions on
a certain region for a given species to survive there.</p>
      <sec id="sec-3-1">
        <title>A. Integration of Regional and Global Taxonomies</title>
        <p>
          The Catalogue of Life (CoL) [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], is a Global Taxonomy
which covers most sectors of the world-wide taxonomic
hierarchy. It aims to cover all known organisms. In contrast, a
regional taxonomy (such as the List of Species of the Brazilian
Flora [8]) only covers species known to occur in the region
addressed by the taxonomy. However, regional taxonomies
often contain richer information than global taxonomies about
species. For example, a more extensive set of synonyms
2https://www.xsede.org/
3https://nanohub.org/
4https://www.sci-bus.eu/
(scientific names other than the “accepted name” for a species),
which either relate to the same or a similar concept, and
descriptive information, may be given. They may also hold
more up-to-date regional information, including information
about some endemic species, which the compilers of global
species lists may not yet be aware of.
        </p>
        <p>
          Taxonomies may also vary in the names used for the same
species, and may even vary in the associated concepts they
represent. For example, a single concept in one taxonomy may
correspond to the union of two distinct concepts in another.
The codes of nomenclature (such as for plants [21] and animals
[
          <xref ref-type="bibr" rid="ref22">22</xref>
          ]) specify how nomenclature is to be performed when the
taxonomy is revised, perhaps merging or splitting concepts, or
rearranging them. Such operations leave clues in the scientific
names generated, which can help in detecting relationships
between these names.
        </p>
        <p>It is desirable to integrate regional and global taxonomies
to attain: (i) more complete and richer information about
individual species than is held in any contributing taxonomy,
and (ii) coverage of a wider range of species than is held in
any one contributing taxonomy.</p>
        <p>An automated process is used in this project to identify
the relationships between species concepts in taxonomies being
integrated, when the accepted scientific names for the concepts
are not the same. This cross-mapping between regional and
global taxonomies is desirable, because: (i) When taxonomies
differ, the concepts may differ (not just the names) making it
impossible to simply integrate them all without losing
information about observations attached to the individual concepts,
and (ii) A user of a regional taxonomy may wish to see how
the species-related data maps into another taxonomy.</p>
        <p>A further complication is that in this paper’s scenarios, the
CoL data comes from a number of Global Species Databases
(GSDs), each with its own specialist coverage of a particular
section of the taxonomic hierarchy. The additional names and
concepts discovered in the other taxonomy can be fed back to
the custodians of the GSDs, for curation to enrich the CoL.
This needs a cross-mapping and a piping tool where the latter
feeds the discoveries of the former to the custodians. This
project provides an opportunity to add knowledge from new
sources to the CoL, and to discover new candidate GSDs for
the CoL which may enrich the information of the CoL.</p>
      </sec>
      <sec id="sec-3-2">
        <title>B. Ecological Niche Modelling</title>
        <p>
          Ecological Niche Modelling (ENM) recently became one
of the most popular techniques in macroecology and
biogeography. There is an impressive growth in related published
papers [
          <xref ref-type="bibr" rid="ref24">23</xref>
          ]. One of the reasons for this trend is the broad range
of applications that arise when the ecological niche of a species
can be approximated and projected in different environmental
scenarios and geographical regions. An ecological niche can
be defined as the set of ecological requirements for a species
to survive and maintain viable populations over time [
          <xref ref-type="bibr" rid="ref25">24</xref>
          ].
ENMs are usually generated by relating locations where the
species is known to occur with environmental variables that
are expected to influence its distribution [
          <xref ref-type="bibr" rid="ref26">25</xref>
          ]. The resulting
model is generated by an algorithm and can be seen as a
representation of the environmental conditions that are suitable
for the species. This makes it possible to predict the impact of
climate changes on biodiversity, prevent the spread of invasive
species, help in conservation planning, identify geographical
and ecological aspects of disease transmission, guide
biodiversity field surveys, and many other uses [
          <xref ref-type="bibr" rid="ref21">26</xref>
          ].
        </p>
        <p>
          This use case addresses computational issues when ENM
is used with a large number of species in complex modelling
strategies involving several algorithms and high-resolution
environmental data. The use case is based on the requirements
of the Brazilian Virtual Herbarium of Flora and Fungi (BVH)
[
          <xref ref-type="bibr" rid="ref28">27</xref>
          ]. BVH has a specific system that uses a standard strategy
to generate ecological niche models for plant species that are
native to Brazil. All species that can be modelled by BVH
come from the List of Species of the Brazilian Flora [8],
which currently contains ∼40,000 entries. Occurrence points
are retrieved from speciesLink [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] - a network that integrates
data from distributed biological collections, currently
serving almost 4 million plant specimen records. The modelling
strategy used by BVH involves generating individual models
using five different techniques in openModeller [28] when the
species has at least 20 occurrence points: Ecological-Niche
Factor Analysis [29], GARP Best Subsets [30], Mahalanobis
distance [31], Maxent [32] and One-class Support Vector
Machines [33]. The model quality is assessed by a 10-fold
crossvalidation, which leads to a final model created by merging the
individual models into a single consensus model, which is then
projected into the present environmental conditions for Brazil
in high-resolution. The aim of this use case is to investigate
and propose efficient ways of generating a large number of
ecological niche models through a Web Service interface that
can be used by applications such as BVH and by a new ENM
Web application that can be integrated in the EUBrazilOpenBio
Virtual Research Environment.
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>C. Requirements</title>
        <p>Requirements were identified in an iterative process of
analysis and refinement by users, systems analysts and
application developers. First of all, there is a need to have seamless
access to fundamental biodiversity data spread across multiple
information systems, like CoL, GBIF, Brazilian Flora Checklist
or SpeciesLink from an integrated access point.</p>
        <p>Secondly, the analysis of such data requires using facilities
to define and execute efficiently and effectively data and
computational intensive workflows, including (a) the execution
of pipelines to search and cross reference taxonomy item
checklists with the objective of identifying missing entities and
inconsistencies; and (b) the generation of multiple species
distribution models by the use of different algorithms and settings.
This includes the need to provide concurrent execution and to
ensure a reasonable Quality of Service by providing scalability
of the resource accessing or processing the available data in a
timely manner.</p>
        <p>Thirdly, the infrastructure should offer a user friendly,
integrated environment, where scientists have innovative services
supporting their data discovery and processing tasks as well
as the sharing and consumption of research results, e.g., the
storage and sharing of species distribution models with other
users thus to avoid recalculation and feedback on results, and
the display of results of the pipelines included in the platform.</p>
        <p>End-user Services</p>
        <p>Core
Services</p>
        <p>Computing
Services</p>
        <p>Storage
Services</p>
        <p>Access</p>
        <p>Services</p>
        <p>Resources Providers
(Clouds, Services, Information Systems)
Fig. 1. EUBrazilOpenBio Infrastructure Conceptual Architecture</p>
        <p>Fourthly, users must be able to upload their own data so that
it can be readily processed using the facilities, e.g., to model
ecological niches. Also, users need to download data stored in
the “system” to be able to process such data with their own
tools. This mitigates any infrastructure “lock-in” fear.</p>
        <p>Finally, the infrastructure should cater for third-party
service providers with web-based programming interfaces for
using infrastructure facilities.</p>
        <p>This project tackles these needs by providing an integrated
infrastructure that has computing and storage resources, and
integrates data and services through a user-friendly interface.
These needs have led to the definition of specific requirements
that are described in detail in the project’s wiki5, and they are
fulfilled by the EUBrazilOpenBio platform.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>III. THE EUBRAZILOPENBIO INFRASTRUCTURE</title>
      <p>
        The EUBrazilOpenBio Infrastructure is an innovative
Hybrid Data Infrastructure [34], conceived to enable a
datamanagement-capability delivery model in which computing,
storage, data and software are made available as-a-Service. In
essence, it builds on the cloud paradigm offering “computing
as a utility” and introduces elasticity of resources and infinite
capacity as key features [35], [
        <xref ref-type="bibr" rid="ref37">36</xref>
        ] with the goal to make data
and data management services available on demand.
      </p>
      <p>
        The second distinguishing feature is its aggregative nature,
i.e., the infrastructure is not built from scratch. Rather, it is a
“system of systems” where the constituents include other
infrastructures, services and Information Systems such as GBIF
[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], Catalogue of Life [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], speciesLink [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], List of Species of
the Brazilian Flora [8], VENUS-C6. EUBrazilOpenBio
Infrastructure integrates these systems with the aim of exploiting the
synergy amongst them, and thus offer biodiversity scientists a
set of novel and enhanced services.
      </p>
      <p>The third distinguishing feature is its capability to support
the creation and operation of Virtual Research Environments
(VREs) [37], [38], i.e., web based working environments
where groups of scientists, perhaps geographically distant from
each other, have transparent and seamless access to a shared
set of remote resources (data, tools and computing capabilities)
needed to perform their work.</p>
      <p>Figure 1 is a schema of the infrastructure’s underlying
architecture. It consists of a number of services interacting
according in a Service Oriented Infrastructure manner [39].
5wiki.eubrazilopenbio.eu
6VENUS-C, www.venus-c.eu (2012)</p>
      <sec id="sec-4-1">
        <title>A. Core Services</title>
        <p>Core services support the operation and management of
the entire infrastructure. These services are from the gCube
software framework [40], [37]. The Information Service has
a key role here, as the infrastructure’s Registry it caters for
resource allocation, discovery, monitoring and accounting. Its
role is to provide a continually updated picture of the
infrastructure resources and their operational state where resou rces
include service instances, hosting nodes, computing platforms,
and databases. It also makes it possible for diverse services
to cooperate by promoting a black-board mechanism, e.g., a
service might publish a resource which is then consumed by
another service. Overall, the service relies on a comprehensive
yet extensible resource model.</p>
        <p>Another core facility is the Resources Management service,
which builds on the Information Service to realise resource
allocation and deployment strategies. For resource allocation
it enables the dynamic assignment of a number of selected
resources to a given community (e.g., the creation of a VRE
requires that a number of hosting nodes, service instances
and data collections are allocated to a given application). For
deployment, it enables the allocation and activation of both
gCube software and external software on gCube Hosting Nodes
(gHN), i.e., servers able to host running instances of services.
By using this facility it is possible to dynamically create a
number of service instances or enlarge the set of available
computing nodes (by deploying a service on a gHN), to realise
the expected elastic behaviour.</p>
      </sec>
      <sec id="sec-4-2">
        <title>B. Biodiversity Data Access Services</title>
        <p>Biodiversity data access services offer facilities enabling
seamless data access, integration, analysis, visualisation and
use of biodiversity data, namely nomenclature data and species
occurrences. Such data represents a key resource for the target
community that is spread across a number of Information
Systems and databases making exploitation challenging [11].
EUBrazilOpenBio offers a species data discovery and access
service (SDDA) which is a mediator over a number of data
sources. SDDA is equipped with plug-ins interfacing with
the major information systems: GBIF and speciesLink for
occurrence data, CoL and List of Species of the Brazilian
Flora for nomenclature data. In order to enlarge the number of
information systems and data sources integrated into SDDA,
it is sufficient to implement (or reuse) a plug-in. Each
plugin is able to interact with an information system or database
by relying on a standard protocol, e.g., TAPIR [10], or by
interfacing with its proprietary protocol. Every plug-in mediates
queries and results from the language and model envisaged by
SDDA to the requirements of a particular database.</p>
        <p>
          SDDA promotes a data discovery mechanism based on
queries containing either the scientific name or the common
name of the target species. Moreover, to overcome the potential
issues related to taxonomy heterogeneities across diverse data
sources, the service supports an automatic query expansion
mechanism, i.e., the query might be augmented with
“similar” species names. Also, queries can specifically select the
databases to search and other constraints on the spatial and
temporal coverage of the data. Discovered data are presented
in a homogenised form, e.g., in a typical Darwin Core [
          <xref ref-type="bibr" rid="ref8">9</xref>
          ]
format.
        </p>
        <p>
          A number of facilities for inspecting the retrieved data
are available, e.g., a geospatial oriented one is available for
occurrence data. Moreover, it is possible to simply “save”
the discovered data in various formats – including CSV and
Darwin Core [
          <xref ref-type="bibr" rid="ref8">9</xref>
          ] – and share them with co-workers through the
user workspace (cf. Sec. III-E). This is a fundamental facility
for the two use cases (cf. Sec. IV).
        </p>
      </sec>
      <sec id="sec-4-3">
        <title>C. File-oriented Storage Services</title>
        <p>
          The file-oriented storage facilities aims to offer a scalable
high-performance storage service. In particular, this storage
service relies on a network of distributed storage nodes
managed via specialized open-source software for
documentoriented databases. This facility is offered by the gCube
Storage Manager, a Java based software that presents a unique
set of methods for services and applications running on the
e-Infrastructure. In its current implementation, two possible
document store systems are used [41], MongoDB and
Terrastore. The Storage Manager was designed to reduce the time
required to add a new storage system to the e-Infrastructure.
This promotes openness versus other document stores, e.g.,
CouchDB [
          <xref ref-type="bibr" rid="ref42">42</xref>
          ], while hiding the heterogeneous protocols of
those systems to the services and applications exploiting the
e-Infrastructure storage facility.
        </p>
      </sec>
      <sec id="sec-4-4">
        <title>D. Computing Services</title>
        <p>Computing services offer a rich array of computing
platforms as-a-Service. This requires harnessing a wide range of
computational resources (from individual computer servers, to
clusters, grids and cloud infrastructures, probably distributed
around the world) efficiently so as to have the potential
capacity to handle the concurrent execution of significant
numbers of experiments. This also implies the need to identify
a set of technologies to allow scientific experiments and tools
to exploit the synergy of the available aggregated processing
capacity within the platform to the fullest extent.</p>
        <p>Workflow and application management systems, such as
the COMPSs programming framework and the EasyGrid AMS,
benefit the infrastructure by acting as enabling technologies to
leverage a range of distributed resource types, such as HPC
clusters (with traditional workload management systems such
as LSF, PBS, and SGE); HTCondor pools (also for
opportunistic computing); and the VENUS-C cloud infrastructure (that
can use both private and public providers including commercial
ones such as Microsoft Windows Azure). The diversity of
resources considered by EUBrazilOpenBio aims to reflect the
most likely scenario of types of infrastructure resources that
would be available to the biodiversity community.</p>
        <p>The VENUS-C middleware has been adopted as one of the
building blocks of the EUBrazilOpenBio computing services.
In particular, the programming model layer, in conjunction
with data access mechanisms, have proven to provide
researchers with a suitable abstraction for scientific computing
on top of virtualized resources. One of these resources is
COMP Superscalar [43], leveraged in VENUS-C to enable
the interoperable execution of use cases on the hybrid cloud
platform. The COMPSs programming framework allows the
development of scientific applications and their seamless
execution on a wide number of distributed infrastructures. In
cloud environments, COMPSs provides scaling and elasticity
features allowing the number of available resources to adapt
to the execution [44].</p>
        <p>HTCondor [45] is a workload management system for
compute-intensive jobs on clusters and wide-area distributed
systems of either dedicated or shared resources. Installed
at over 3000 sites around the world, HTCondor provides a
job queuing mechanism, scheduling policy, priority scheme,
resource monitoring, and resource management that allows
users to execute either serial or parallel jobs. With
HTCondor’s metascheduler, and Directed Acyclic Graph Manager
(DAGMan) [46], HTCondor can manage task dependencies
within a job, e.g., a Condor job may be configured to perform
the modelling step first, and thereafter perform steps to test
and project the model in parallel. Given the computational
requirements of an experiment can be large, an additional
feature in this deployment is pool elasticity. Node virtualization
allows additional resources to be added on-demand to increase
availability, and performance.</p>
        <p>While systems like VENUS-C has COMPSs and
HTCondor has DAGMan, others systems without a local workflow
manager can use the EasyGrid AMS [47]. The EasyGrid
middleware is a hierarchically distributed Application
Management System (AMS) embedded into parallel MPI
applications to facilitate efficient execution in distributed
computational environments. By coupling legacy MPI applications
with EasyGrid AMS, they can be transformed into autonomic
versions which manage their own execution. The benefits of
this approach include adopting (scheduling, communication,
fault tolerance) policies tailored to the specific needs of each
application thus leading to improved performance [48]. While
the EasyGrid AMS is being used to accelerate phases of
openModeller through parallelisation, given that workflows can
be seen to be directed acyclic graphs, the AMS can also be
used to encapsulate the entire workflow and manage their
execution in distributed systems without workflow managers.</p>
      </sec>
      <sec id="sec-4-5">
        <title>E. End-user Services</title>
        <p>End-user services provide human users with facilities
benefitting and building upon the resources the infrastructure
aggregates. The majority of these services appear in a
webbased user interface and all of them are conceived to be
aggregated and made available via VREs hosted by a portal.</p>
        <p>These services include infrastructure management facilities
(e.g., VRE deployment facilities, user management, resource
management) and user collaboration (e.g., shared workspace,
data discovery facilities, data manipulation facilities). We now
describe the facilities specifically exploited to support the two
use cases.</p>
        <p>The Workspace is a user interface implemented through
portlets, that provide users with a collaborative area for storing,
exchanging and organizing information objects according to
any specific need. Every user of a VRE is provided with this
area that resembles a classic folder-based file system, with
seamlessly managed item types that range from binary files
to compound information objects representing tabular data,
species distribution maps, and time series. Every workspace
item is equipped with rich metadata including bibliographic
information like title and creator as well as lineage data. In
addition to information object storage and organisation, the
portlet allows easy exchange of objects among users as well as
import/export of objects from/to the user file system to enable
processing such objects using both the infrastructure and local
users’ computers.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>IV. IMPLEMENTATION OF THE USE CASES</title>
      <p>The facilities of the EUBrazilOpenBio infrastructure are
made available via a dedicated portal7 which hosts the VRE
resulting from the implementation of the use cases. The
software artchitecture of both use cases is shown in Figure
2. End-users are provided with specific portlets, each realising
one use case. These portlets are integrated with others portlets,
namely SDDA and Workspace for data access. Each use
cases’ portlet interact with the processing services through
specific services that implements the functionality of the use
case. Different computing and data resources are accessed
through a combination of services and plug-ins that hide the
particularities of each source and back-end.</p>
      <sec id="sec-5-1">
        <title>A. EUBrazilOpenBio Taxonomy Management Facilities</title>
        <p>The basis of the software components developed in the
first use case was the cross-mapping tool implemented in the
i4Life8 project. However, although the actual cross-mapping
software is essentially the same in both systems, the
environment and modes of interaction have been completely
redesigned, moving from a simple web site, developed in
PHP and Perl, in which the users had to interact with it
manually, to a system in which all its functionality is accessible
programmatically through a Web service interface, thereby
making it more suitable for deployment as part of a distributed
architecture. With its new portlet, the cross-mapping tool is
now integrated with other software components provided by
the EUBrazilOpenBio infrastructure (workspace, information
system, SDDA, etc.), making it easier for the user to run
crossmapping experiments.</p>
        <p>The migration has also achieved a reduction in the
execution time of large cross-mapping tasks (e.g., by limiting the
7https://portal.eubrazilopenbio.d4science.org
8http://www.i4life.eu/
size of tables of names created during checklist import) and can
display the results of the cross-map in a tree view perspective,
not currently available in i4Life.</p>
        <p>The software developed for this use case can be divided
into two categories: a SOAP web service with MTOM [49]
which exposes a set of methods that allow the clients to
upload checklists, run cross-map experiments and export their
results, and a portlet that interacts with the cross-map service
alongside other services and tools provided by the
infrastructure. Checklists are seamlessly obtained from the SDDA
infrastructure service, and communication between the VRE
and the processing services is done through the infrastructure
storage services. This eases the development of applications
and the sharing of data among users and services.</p>
        <p>
          Internally, the cross-map service was developed using a
layered approach. The service interface layer defines the public
interface of the service (using a WSDL file). Another layer
provides the logic of the application; this can also be called
from a command line without using the web-service. These
interfaces are specified and generated using the Tuscany SCA
[
          <xref ref-type="bibr" rid="ref36">50</xref>
          ], a framework that allows declarative exposure of Java
components into a plethora of different protocols, such as
SOAP, Rest or JMS.
        </p>
        <p>The portlet (cf. Figure 3) was developed jointly by CNR
and Cardiff University; it is basically a GWT9 project that
uses the GXT10 3.0 library which provides rich web-based
widgets. Also XML files have been added to deploy it as
a Liferay portlet inside the project’s portal. Internally the
software interacts with the workspace to retrieve and store
input and output data for the cross-mapping tool as well as
querying the information system to obtain the instance of the
cross-map web service to be used.</p>
        <p>The web service and the portlet are deployed as Web
Archive (war) files: (i) the portlet is deployed in the
EUBrazilOpenBio portal; (ii) the cross-map web service is
deployed in a web server container, registering its service
endpoint in the Information System as an external resource.</p>
        <p>At the moment, the cross-map service processes all the
operations sent by the portlet locally. However, to make the
application more scalable, the cross-map service will externalize
the execution of some of those operations, depending on their
complexity, to other resources provided by the infrastructure.</p>
      </sec>
      <sec id="sec-5-2">
        <title>B. EUBrazilOpenBio Niche Modelling Facilities</title>
        <p>The original openModeller Web Service (OMWS) API
exposes a set of operations defined by an XML schema
having all elements, attributes, structure and data types of the
openModeller objects. Each operation defined by this scheme
supports the execution of one simple action in openModeller,
for example, to create, test or project a model. When a user
wants to perform several actions on the same dataset, it is
necessary to submit each operation to the service separately.
For example, to create five models with the same species
occurrence dataset using five different modelling algorithms,
five different requests are needed (one per algorithm). This
also occurs for experiments that create models for different
9https://developers.google.com/web-toolkit/
10http://www.sencha.com/products/gxt
species using the same modelling algorithm. When there are
dependencies between the operations, such as, creating a model
and then projecting it onto an environmental scenario, the
client is responsible for sending the initial request, monitoring
and retrieving the results of the operation that creates the model
and also including the serialized model as an input parameter
in the projection operation that follows.</p>
        <p>An extension of the openModeller Web Service API
(namely OMWS+) provides a way to automatically
convert multi-stage and multi-parameter experiments into a set
of single legacy operations supported by the openModeller
command-line suite. Support for user sessions is also included
for enhanced monitoring and retrieving of results. This is
currently implemented through COMPSs, which orchestrates
the execution after automatically generating the execution
graph (cf. Fig. 2).</p>
        <p>This component exploits the advantages of the concurrent
execution of the infrastructure and makes use of the storage
services provided. The GUI implemented on the VRE
integrates with the rest of the services so the user interacts with
an editor application that enables the creation of experiments
that are converted into multiple concurrent jobs with the results
being gathered in a single view. It provides a comprehensive
visualization of all the species and algorithms and provides
a progress report that enables progress monitoring of the
experiments and retrieving their results from any web browser.</p>
        <p>The implementation of the COMPSs Job Manager on
the VENUS-C PMES, receives the execution request from
the Orchestrator dispatching users’ requests received from
the OMWS+ interface to support multi-staging and
multiparametric experiments through COMPSs and openModeller.
These extensions are backward compatible with the original
OMWS specification, which allows legacy clients to be fully
supported in the new implementation and, therefore, still able
to submit experiments to the execution resources without using
the graphical user interface developed by the project. The
infrastructure hides the complexity of accessing data sources
and data repositories. Data sources are integrated through the
SDDA and data storage provided by the infrastructure can be
accessed by the VRE and the processing instances, facilitating
the sharing of data and storing them permanently on the users’
specific storage. A snapshot is shown in Figure 4.</p>
        <p>This service was tested on 10 quad-core virtual instances
with 2GB of memory and 1GB of disk space on the
EUFig. 4. Ecological Niche Modelling GUI snapshot
BrazilOpenBio infrastructure. The aim of these tests was to
validate the workflow implementation and to evaluate the
advantage of the elasticity features of these services. Eight
species of the genus Passiflora, each one with more than 20
occurrence points, were used. Models were generated using
8 high resolution environmental layers from WorldClim. A
simplified standard procedure consisting of model creation
followed by an internal model test (confusion matrix and
ROC curve calculation with the same input points) and a
native model projection (with the same environmental layers)
followed by a final image transformation was used for each
species with a set of three algorithms used by BVH (SVM,
ENVDIST and ENFA) called with a different set of parameters.
The Brazilian territory served as a mask in all operations.
This scenario composes a total of 46 simultaneous single
operation requests. Experimental results [51] demonstrate that
the ENM service reaches good performance running on an
ondemand provided environment (with an average performance
loss around 9.6% with respect to a dedicated cluster), reaching
a speed-up above 5 with the 10 machines.</p>
        <p>V.</p>
        <p>CONCLUSION</p>
        <p>The EUBrazilOpenBio infrastructure is an integrated
escience platform for biodiversity researchers. It goes beyond
integration of resources by providing seamless access to data,
services and collaboration facilities. The concept of Virtual
Research Environments requires a short learning curve, and
integration of computing and visualization services reduces the
need to transfer data from and to the infrastructure.</p>
        <p>The integration of multiple technologies and services
required development of intermediate services which orchestrate
and virtualize different resources. The exploitation of
commonly accepted protocols for data and services enables the use
of the resources through web-based programming interfaces.</p>
        <p>Requirements in these examples of biodiversity research
also show the need to be able to use a user’s own data,
both lightweight data (taxonomies or occurrence points) and
big data, such as environmental layers. Bandwidth usage
minimization is a key issue in performance improvement.</p>
        <p>The selection of two representative use cases has enabled
the creation of demonstrators and the validation of specific
requirements which are common to many other applications.
Generic services provide building blocks for such applications.</p>
        <p>The technologies used are open and extensible and
interoperability is important to maximise the integration of different
data sources and computing backends. Although the
requirements elicited from the use cases focused on the cross-mapping
of taxonomies and ecological niche models, the infrastructure
has been designed and the services were implemented to fulfil
the needs of a wide range of biodiversity applications. The
main technical advance of EUBrazilOpenBio is the integration
of diverse data sources, processing services, computing and
data resources in a unique science gateway. Both applications
available through the VRE have been tested by scientists as
part of the project and are ready to be used.</p>
        <p>EUBrazilOpenBio provides the scientists with a single
access point to a wide range of Biodiversity resources.
EUBrazilOpenBio storage enables a seamlessly and ubiquitous
access to reference data and experiment results. Taxonomy
checklists, occurrence points, ecologic niche models,
projection maps, etc. can be exchanged and visualized from the VRE,
without requiring local applications nor downloading output
files. Users of this integrated framework also benefit from the
high-performance computing back-ends of the platform.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>ACKNOWLEDGMENT</title>
      <p>EUBrazilOpenBio - Open Data and Cloud Computing
e-Infrastructure for Biodiversity (2011-2013) is a Small or
medium-scale focused research project (STREP) funded by
the European Commission under the Cooperation Programme,
Framework Programme Seven (FP7) Objective
FP7-ICT-2011EU-Brazil Research and Development cooperation, and the
National Council for Scientific and Technological
Development of Brazil (CNPq) of the Brazilian Ministry of Science,
Technology and Innovation (MCTI) under the corresponding
matching Brazilian Call for proposals MCT/CNPq 066/2010.</p>
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