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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Managing Quality Related Information in Software Development Processes</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Vladimir A. Shekhovtsov</string-name>
          <email>Volodymyr.Shekhovtsov@aau.at</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Heinrich C. Mayr</string-name>
          <email>Heinrich.Mayr@aau.at</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Institute for Applied Informatics, Alpen-Adria-Universität Klagenfurt</institution>
          ,
          <country country="AT">Austria</country>
        </aff>
      </contrib-group>
      <fpage>73</fpage>
      <lpage>80</lpage>
      <abstract>
        <p>An effective communication between the parties in the software development process is important for coming to and complying with appropriate agreements on the quality of the prospective software. Such communication is impaired when developers and business stakeholders perceive quality differently. To address this problem, we aim at a solution that supports understandability and reusability of quality-related communicated information, and the quality of decisions based on this information. In this paper, we first introduce a set of knowledge structures for representing communicated information and then discuss how to map raw communication data into these structures.</p>
      </abstract>
      <kwd-group>
        <kwd>elicitation</kwd>
        <kwd>semantic annotation</kwd>
        <kwd>software development process</kwd>
        <kwd>software quality</kwd>
        <kwd>communicated information</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        Software development processes require a continuous involvement of the affected
business stakeholders in order to be successful (this requirement, in particular, is
reflected by the ISO/IEC standard for software life cycle processes [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]). A prerequisite
of such involvement is establishing an appropriate communication basis for the
different parties. In particular, such a basis is needed for coming to terms and
agreements on the quality of the software under development. Without this, quality defects
are often detected only when the software is made available for acceptance testing.
      </p>
      <p>Clearly, besides of enabling effective communication, the communicated
qualityrelated information has to be managed properly and made available during the
software development lifecycle; moreover, as past-experience may help to take the right
decisions, such information should be provided in a way that allows for easy access
(e.g., via an issue management system) and analysis.</p>
      <p>
        The QuASE project1 [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] aims at a comprehensive solution for these issues. In
particular, this solution will provide support for managing (1) the understandability of
quality-related communicated information, (2) the reusability of that information, and
(3) the quality of decisions based on that information.
1 QuASE: Quality Aware Software Development is a project sponsored by the Austrian
Research Promotion Agency (FFG) in the framework of the Bridge 1 program
(http://www.ffg.at/bridge1); Project ID: 3215531
      </p>
      <p>In this paper, we concentrate on the knowledge structures representing
qualityrelated communicated information and on the mapping of raw communication data
into these knowledge structures.</p>
      <p>The paper is structured as follows. Section 2 introduces the sources of quality
related information and defines the knowledge structures representing QuASE quality
characteristics. Section 3 describes the mapping of communicated information into
these knowledge structures. After a short discussion of related work in Section 4, the
paper concludes with a summary and an outlook on future research (Section 5).
2</p>
    </sec>
    <sec id="sec-2">
      <title>Knowledge Structures for Representing Quality Related</title>
    </sec>
    <sec id="sec-3">
      <title>Communicated Information</title>
      <p>
        Usually, industrial software development projects keep communicated information
within repositories such as
1. project databases controlled by issue management systems, e.g., JIRA [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ],
MantisBT [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and others; such databases contain communicated information in form of
so-called issues that (generalizing communication units as bug reports or feature
requests) and related discussions;
2. file-based repositories containing meeting minutes, requirement and design
specifications etc.; these files are usually kept in some kind of a directory tree under the
control of configuration management systems; these documents, as a rule, are
updated less frequently as compared to issues and the relevant discussion threads;
3. wiki-based systems.
      </p>
      <p>Consequently, QuASE considers these types of repositories as sources of
qualityrelated communicated information and therefore provides interfaces to them.</p>
      <p>The raw data collected from these sources are interpreted and mapped into the
QuASE QuIRepository the structure of which (defining a generic metamodel
representing semantic relationships) is depicted in figure 1 and subsequently explained.
site
defines
defines</p>
      <p>context
documents
related
to
shapes
contain
knowledge
content
is interpreted
according to
1. QuASE site: owner of the given QuASE installation, e.g. a software provider.
2. QuASE context: units having particular views on communicated information, e.g.
projects, organizations and their departments, involved people (stakeholders) etc..
Context units are characterized by context attributes and can be connected to other
units; a context configuration, for example, could include the representation of the
whole organizational hierarchy or the whole portfolio of projects defined for a
particular IT company.
3. QuASE documents: units shaping communicated information: they serve as
containers for such information or organize such containers. We distinguish content
holders and content directories organizing the holders. Examples of document
units are issues and their sets, issue attribute values, requirement specifications and
their structural elements. For the case of issues, the issues or their sets are
examples of content directories, whereas issue descriptions and discussion opinions are
examples of content holders. Document units can be related to particular context
element. A detailed description of the context and document concepts is target of a
separate publication.
4. QuASE knowledge: quality and domain knowledge that is subject of
communication and harmonization. We organize it into knowledge modules representing
particular views. The configuration of these modules reflects the configuration of
context, i.e., the modules and their relationships correspond to context elements and
their interrelationships. Below, these modules will be described in more detail.
5. QuASE content: the information that has to be communicated. It is shaped by
context units and interpreted according to the respective knowledge. Dealing with the
content is decoupled from dealing with their holder documents; i.e., we can think
of this content as of a uniform stream of data (which is given as tagged natural text
in the current QuASE implementation). On the other hand, while dealing with
documents, we abstract from their content and delegate dealing with this content to the
generic content processing routines.</p>
      <p>
        The QuASE knowledge modules are organized into a modular ontology
(QuOntology) thus providing a framework for translating between world views. Initial research
on QuOntology has been published in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], whereas the current version of the
relevant conceptualizations is presented in [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>
        QuOntology is organized in three layers [see also Fig. 2]:
1. QuOntology core represents a stable subset of the knowledge available from
research and industrial practice; this knowledge does not depend on the particular
problem domain and the particular context. We use the Unified Foundational
Ontology (UFO) [
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ] as a foundation for QuOntology core.
2. Domain ontologies [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] represent the specifics of the particular problem domain
which is addressed by the given software under development (finance, oil and gas
etc.); domain ontology concepts specialize core concepts; as a part of the project,
we implement for this layer an ontology for quality in the software domain [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
3. Context ontologies represent the knowledge related to particular components of the
QuASE context: they contain organization-specific, project-specific etc. concepts.
These concepts specialize the generic concepts of the upper level ontologies but
also may be specializations of other context ontologies; we implement for this layer
ontologies for business-specific and IT-specific views on quality;
To deal with changes in the structure of context and document units, we will provide
a notation for specifying context and document configurations, which will be
supported by the metamodeling tool ADOxx (http://www.adoxx.org); this will allow the
responsible people (knowledge suppliers) to create and modify the desired
configuration. The relevant database structure will be generated based on this configuration.
      </p>
    </sec>
    <sec id="sec-4">
      <title>Mapping communicated data into QuIRepository structures</title>
      <p>The correspondence of communicated data and QuIRepository structures is made
explicit by mapping specifications of a particular mapping mode.</p>
      <p>For brevity, in this section we restrict ourselves to the mapping of repositories that
are controlled by an issue management system (e.g. JIRA databases) further referred
to as mapping sources. Mappings involving other categories of repositories (e.g.
filebased repositories or wikis) are based on similar principles. Also, we omit the
treatment of the mapping of concept relationships.
3.1</p>
      <sec id="sec-4-1">
        <title>Mapping context structure</title>
        <p>To define appropriate mappings for the context concepts we distinguish the
following mapping modes:
1. Direct mode: a given communicated context-related structure (e.g. a JIRA database
table) is mapped one-to-one into a QuIRepository context structure;
2. Join mode: several communicated context-related structures are mapped into a
single QuIRepository context structure;
3. Split mode: a single communicated context-related structure is mapped into several</p>
        <p>QuIRepository structures;
4. Interactive mode: the whole instance of the context concept has to be specified by
the user through the respective user interface.</p>
        <p>Specifications for mapping context attributes are nested into the specifications
defined for context concepts. We distinguish the following mapping modes:
1. Direct mode: a single communicated attribute (e.g. defined as an attribute in a
context-related relation) is mapped into a single QuIRepository context attribute. The
data is extracted without any user interaction. Example: mapping the “project
name” attribute of a JIRA project table to the “project name” attribute of the
corresponding QuIRepository “project” context unit;
2. Calculated mode: one or several communicated attributes are mapped to a
QuIRepository context attribute based on a predefined metric function;
3. Interactive mode: the QuIRepository context attribute cannot be derived
automatically from the communicated data; in this case, the QuASE tool shows an
elicitation user interface and collects the concept information from the expert user.
3.2</p>
        <p>Mapping document structures
1. Mapping document concepts: is defined similarly to the direct context mapping
mode: the communicated document structure is mapped to a specific
QuIRepository document structure. As an example, a JIRA “issue” table is mapped to the
“issue” document structure, whereas the comments to the issues or issue descriptions
are mapped into, correspondingly, “comment” or “issue description” content
holders.
2. Mapping document attributes: For the document attributes, the mapping is defined
through the same three modes as specified above for context attributes; the main
difference is due to the fact that it is possible to distinguish calculated attributes
based on the content held directly by the document unit (for the case of content
holders) or by the related holders (for the case of content directories).
3. Mapping content holders: For content holders, the approach is to delegate all the
processing of mapping the content to the specific content-mapping activities such
as text-based semantic annotation as specified in the following section.
3.3</p>
      </sec>
      <sec id="sec-4-2">
        <title>Mapping content</title>
        <p>Mapping content stream into QuASE concepts is performed by associating concepts
with text fragments of the stream. To perform such an association, the QuASE
system:
1. scans the natural language content stream looking for candidate context-specific
terms;
2. associates tags with candidate terms that correspond to available knowledge in
QuOntology; applying a tag indicates that the corresponding term can be
associated with a QuOntology concept in at least one ontology module;
3. makes the tags act as anchors for connections to the related QuOntology concepts;
to do this, for every tagged term the tool looks for concepts in all available context
ontology modules.
The Term knowledge context then is the set of all concepts found for the given term; it
defines all possible context-specific views of this term, and allows for switching
between such views.</p>
        <p>Fig.3 visualizes the process of associating context-specific terms with tagged
documents exemplified by JIRA issues.
In this section, we discuss two categories of the related work: (1) approaches
addressing the complete set of goals for QuASE, and (2) approaches addressing the particular
task of obtaining the data from project repositories for analytical purposes.</p>
        <p>
          The approach discussed here belongs to the category of solutions that facilitate
storing, reusing, adapting, and analyzing the development knowledge. In particular
such solutions apply the existing body of research on knowledge management to the
field of software engineering [
          <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
          ]. A more specific category of solutions is related to
managing past software engineering experience; they are known as experience
management solutions [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ].
        </p>
        <p>With respect to our aims, these solutions bear the following shortcomings: (1) they
do not specifically address quality-related issues, which is true especially for those
issues that are available from existing repositories like issue management systems; (2)
they collect the experience only as viewed from the developer side; the business
stakeholder’s view is mostly ignored, and it is not possible to switch between views
while considering collected experience.</p>
      </sec>
      <sec id="sec-4-3">
        <title>Solutions for obtaining information from project repositories</title>
        <p>
          Approaches that aim at obtaining information from project repositories for
analytical purposes, typically belong to the research area of mining software repositories [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
Particular examples of such approaches include automatic categorization of defects
[
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], building software fault prediction models based on repository data [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ], and
using repositories to reveal traceability links [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. Other approaches use repository
information to analyze the applicability of specific development practices [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ].
        </p>
        <p>Repository mining solutions use software repositories as sources of quantitative
code- and coding process-related information (such as the frequency of bugs, the time
spent on various tasks, information about commits into repositories etc.). In contrast
to that, QuASE uses repositories as sources for communicated information by looking
into issue descriptions, negotiation opinions, wikis, and requirements documents.</p>
        <p>In addition to the difference in the general goals, the QuASE approach differs from
these solutions in the following implementation-related aspects: (1) it conceptualizes
the process of collecting information from repositories as mapping operations
controlled by mapping specifications; (2) it is based on an established set of conceptual
structures that represent context and document units, content stream, and
viewspecific ontological knowledge.
5</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusions and future work</title>
      <p>In this paper, we outlined a solution that is intended to support understandability and
reusability of quality-related information, and thus may help to improve the quality of
decisions in the software development process. The QuASE provides a
knowledgeoriented interface to information that is communicated and collected in the course of
software development projects. For this purpose, we introduced a set of knowledge
structures addressing quality characteristics; these include context-, document-and
content-specific structures as well as the structures for knowledge that defines
particular views. We then defined the various kinds of modes for mapping communicated
information (such as the data available in the project databases or document
repositories) into these knowledge structures.</p>
      <p>Ongoing research within the framework of the QuASE project aims at realizing the
following features based on the defined conceptual structures:
1. Understandability support: document units are analyzed with respect to potential
understandability problems for the target context (e.g., when they units are to be
presented to a non-expert business stakeholder; identified problems are solved by
translating or explaining the problematic terms using the respective knowledge
structures.
2. Reusability support: for a given document, all similar ones (with respect to the
required knowledge level) are searched based on the attributes of the documents
and/or context units.
3. Quality of decisions support: recommendations for dealing with documents and
context elements during the communication; forecasts of metrics values, and
performing “what-if” analyses for particular decisions.</p>
    </sec>
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