Blekinge Institute of Technology
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Capturing Value in Conceptual PSS Design : Perspectives from the Automotive Supply Chain
No full textManufacturing companies have traditionally focused their design and development
activities on realizing technical and engineered aspects of physical artifacts
based on performance requirements. The ever-changing business climate, with its
increased pace during the past decades, has forced industries to continuously
innovate their approach toward the development of new products. Pressured also
by global competition, manufacturing companies need to reconsider the
traditional concept of realizing value via goods production, and shift towards
realizing value through product-service combinations.
Companies have begun to recognize that gaining competitive advantage and
expanding market shares is not achievable purely through continuous technical
improvements. Rather, it is necessary to develop a closer relationship to the
customer to gain a deeper understanding of expectations, needs, and perceived
value.
From a development perspective, the overarching problem within complex
systems such as those in which cars, aircraft, and excavators are manufactured,
or healthcare is provided, is that the focus on customer value is likely to
become blurred since it is difficult to understand the impact a change in any
single component in the overall system has on value, and to determine a new
function’s impact on future scenarios.
The main goals of this thesis are to provide an understanding of key
challenges when considering the value different design alternatives provide in
the conceptual phases of product development taking the automotive industry as
case study, and to explore how to support a multi-disciplinary design team in
making value-conscious decisions when dealing with new product-service
offerings. The research approach has involved data collection through
participation in, and facilitation of, product-service design workshops in the
automotive industry. Also, it has involved follow-up meetings and interviews,
as well as a review of literature on state-of-the-art methods in early
conceptual design phases, which describes the advantages and disadvantages of
the different frameworks.
The primary finding of the study is that determination of the impact of
different PSS design options on customer value becomes more challenging since
new elements are introduced (e.g., new business models and services). The
design team requires more holistic competences in order to more fully
understand changing contexts; and new methods and tools are needed in order to
establish a base to define, discuss and assess what “uncontested customer
value” is, and link it to the different product-service elements of the system.
Secondly, this thesis proposes a conceptual approach for value simulation and
assessment of different design options, where the iterative use of personas and
scenario generation is combined with value modeling and computer-based
simulation techniques, enabling a quick “what-if” analysis of the various
options, facilitating the identification of promising combinations of product
and service elements that provide higher customer value
On Multi-channel Opportunistic Access in Heterogeneous Cognitive Radio Networks
No full textIn the paper, we study optimal transmission strategies in multi-channel
opportunistic spectrum access (OSA) networks where one secondary user (SU)
opportunistically accesses multiple orthogonal channels of primary users (PUs)
under a continuous time Markov chain modeling of the channel occupancy by the
PUs.
Referred to as tunable threshold strategy, at a given time
the SU chooses one channel of a given PU, decides if it should transmits or not
and if so it protects the PU of this channel.
To be operational, such a structure depends on the capability of the SU radio
front-end to perform channel sensing.
We consider one scenario where the SU node can simultaneously sense multiple
channels and another scenario where the SU node can sense only one channel at a
time.
For each scenario, we develop the structure of the optimal transmission
strategy and analyse the performance.
We show that the optimal transmission strategy can be implemented using a
simple tunable threshold algorithm
Tailoring the Software Product Management Framework for Use in a Healthcare Organization: Case Study
No full textMany reference models were developed for software process improvement. Each
model, however, is an idealized prescription that is applicable in a lim-ited
set of situation only. This paper has investigated how an existing refer-ence
model can be tailored to a domain it has not been designed for initially. The
tailoring approach is based on translating the reference model to the new
domain and on inductive interviews for evaluating the translated model. The
approach has been applied for assessing and improving strategic require-ments
engineering practice in a healthcare organization with a framework for software
product management
Value-oriented concept selection in aero-engine sub-systems design: the EVOKE approach
No full textValue Driven Design methodologies extend the Requirements Management and
Systems Engineering processes to reduce time and costs needed to identify the
right solution direction to be pursued in detailed design. Emerging from the
findings of an EU FP7 research project, the paper describes an approach, named
EVOKE, that uses value as a basis for preliminary concept selection in the
design of system components. EVOKE takes as input a list of value dimensions
and drivers communicated by the system integrators, together with information
about the high-level engineering characteristics of a candidate design, to
enable early stage value analysis to be executed the by sub-system
manufacturers. The approach and its technological enablers are described in
detail through the use of a case study related to the design of new
intermediate compressor case for turbofan engines
Understanding the Impact on Software Quality for Evolving Systems in Distributed Development Environments
No full textContext: The existing body of knowledge falls short of providing comprehensive
empirical evidence on the impact that global software development (GSD)
strategies have on software quality during software evolution. The realization
of expected benefits of such GSD strategies, e.g. reduced costs, should not be
taken for granted. Challenges faced can negatively impact quality, which can
consequently inhibit the realization of the potential benefits.
Objective: This licentiate thesis provides empirical evidence pertaining to the
effect on quality for evolving systems in distributed development environments.
The aim is to provide empirical evidence that can be useful input in the
decision-making process for future GSD projects that are executed in
distributed development environments.
Method: The findings presented in this licentiate thesis are obtained from
three empirical studies and one extensive systematic literature review. The
empirical studies were conducted at two large multinational corporations.
Meanwhile, the purpose of the systematic review was to obtain empirical
information that was used to successfully execute one of the empirical studies.
All empirical work was done using both quantitative data (e.g., defect data,
features per release, source code measures, release history) and qualitative
data (e.g., interviews, focus group meetings, questionnaires, and analysis of
company documentations).
Result: Transfers have a potentially negative impact on quality and efficiency.
Observations that were made on quantitative data in all three empirical studies
were triangulated with subjective opinions that were obtained from
practitioners. When studying the quality of a large software system, a
significant decrease in quality was identified; similarly in a study focusing
on maintenance work efficiency two studied large software products showed a
noticeable decrease. Meanwhile, there was no discernible impact on quality for
two products, as a result of distributed development and the handover of
responsibilities between involved sites. Transfer critical factors, which can
impact quality, as well as transfer enabling factors, which can alleviate
transfer-related issues, were also identified from these empirical studies.
Conclusions: Companies that engage in software transfers should expect a
decline in quality during and immediately after a transfer. There are
practices, such as, engaging in distributed development, and the gradual
handover of responsibilities, that can alleviate transfer-related issues. The
findings in this licentiate thesis can be a valuable input in the
decision-making process for companies engaging in transfers in GSD contexts,
and thus help in making informed decisions in current or future transfers.
Moreover, this licentiate thesis shows that analyzing the evolution of size and
complexity properties of a product’s source code, and defect data, can also
provide useful objective data to support decision-making during similar
projects
Uni-REPM: Validated and Improved
No full textSoftware products are usually developed for either a specific customer
(bespoke) or a broader market (market-driven). Due to their characteristic,
bespoke and market-driven development face different challenges, especially
concerning requirements engineering. Many challenges are caused by an
inadequate requirements engineering process, and hence there is a need for
process improvement frameworks based on empirical research and industry needs.
In a previous article we introduced Uni-REPM, a lightweight requirements
engineering process assessment framework based on a review of empirically
motivated practices in market-driven and bespoke requirements engineering
literature. In this article, we validate this framework in academia as well as
industry, in order to prepare Uni-REPM for widespread industry use. We conduct
two validations; a static validation based on interviews with seven academic
experts and a dynamic validation where Uni-REPM is applied in four industrial
organisations. Uni-REPM is refined according to the feedback obtained in the
validations. The study shows that Uni-REPM is a quick, simple, and
cost-effective solution to assess the maturity level of the requirements
engineering process of projects. Moreover, the assessment method using
checklists is highly usable and applicable in various international development
environments
Performance Assessment of Cooperative Relay Networks with Advanced Radio Transmission Techniques
No full textIn the past decade, cooperative communications has been emerging as a pertinent
technology for the current and upcoming generations of mobile communication
infrastructure. The indispensable benefits of this technology have motivated
numerous studies from both academia and industry on this area. In particular,
cooperative communications has been developed as a means of alleviating the
effect of fading and hence improve the reliability of wireless communications.
The key idea behind this technique is that communication between the source and
destination can be assisted by several intermediate nodes, so-called relay
nodes. As a result, cooperative communication networks can enhance the
reliability of wireless communications where the transmitted signals are
severely impaired because of fading. In addition, through relaying
transmission, communication range can be extended and transmit power of each
radio terminal can be reduced as well.
The objective of this thesis is to analyze the system performance of
cooperative relay networks integrating advanced radio transmission techniques
and using the two major relaying protocols, i.e., decode-and-forward (DF) and
amplify-and-forward (AF). In particular, the radio transmission techniques that
are considered in this thesis include multiple-input multiple-output (MIMO)
systems and orthogonal space-time block coding (OSTBC) transmission, adaptive
transmission, beamforming transmission, coded cooperation, and cognitive radio
transmission.
The thesis is divided into an introduction section and six parts based on
peer-reviewed journal articles and conference papers. The introduction provides
the readers with some fundamental background on cooperative communications
along with several key concepts of cognitive radio systems. In the first part,
performance analysis of cooperative single and multiple relay networks using
MIMO and OSTBC transmission is presented wherein the diversity gain, coding
gain, outage probability, symbol error rate, and channel capacity are assessed.
It is shown that integrating MIMO and OSTBC transmission into cooperative relay
networks provides full diversity gain. In the second part, the performance
benefits of MIMO relay networks with OSTBC and adaptive transmission strategies
are investigated. In the third part, the performance improvement with respect
to outage probability of coded cooperation applied to opportunistic DF relay
networks over conventional cooperative networks is shown. In the fourth part,
the effects of delay of channel state information feedback from the destination
to the source and co-channel interference on system performance is analyzed for
beamforming AF relay networks. In the fifth part, cooperative diversity is
investigated in the context of an underlay cognitive AF relay network with
beamforming. In the sixth part, finally, the impact of the interference power
constraint on the system performance of multi-hop cognitive AF relay networks
is investigated
Mediernas roll i kommunikation och utbildning
No full textDe digitala mediernas popularitet visar att virtuella erbjudanden om
kommunikation fyller många människors behov. Ett perspektiv omfattar
vardagsanvändning av Internet. Ett annat perspektiv omfattar distanskurser i
högre utbildning. Ett tredje perspektiv avser beskrivningar av teknologins
påverkan på praktiken. Kommer föreläsningar att försvinna, hur organiserar
studenterna grupparbete på nätet, vilken kunskap följer av en given pedagogisk
design? Det här numret innehåller komplementära åsikter om spelbaserat lärande
och en karaktäristik av några generella villkor för IT-medierade praktiker.
Rose-Marie Olsson kartlägger villkoren för reflekterat lärande genom självstyrd
visualisering. Jennifer Petersson beskriver spel som motivations- och
intresseskapande undervisningsdesign. Martin Svensson utvärderar aktörernas
hantering av känslor och beslutsfattande samt anger konsekvenserna för
IT-medierad högre utbildning
Road travel time prediction - A micro-level sampling approach
No full textThe ability to generate accurate travel time predictions
for road freight transport is important when, for example,
estimating the arrival times for heavy goods vehicles (HGVs)
in order to plan terminal activities. We present a micro-level
sampling method for road travel time prediction. The method
makes use of historical GPS-data in order to determine the
movement of a vehicle from an origin to a destination along a
specific route. The method generates a travel time distribution,
which can be used to obtain the expected travel time and
probabilities for deviations. The method has been illustrated
and evaluated in an experiment where the effective travel
time was predicted for transport between two terminals. The
experiment made use of GPS data that was recorded for two
HGVs during a period of two months. An important feature of
the method is that it does not need road network information,
such as speed limits and number of lanes
A framework for software usability & user experience measurement in mobile industry
No full textThe mobile industry faces challenges in designing software usability and user
experience (UX) measurement instruments. The major difficulties arise due to:
1) diversity of definitions and terminology used for usability and UX aspects
and attributes, which lead to inconsistencies, and 2) lack of a taxonomy for
these attributes with links to well-defined measures in the literature. In this
paper, we present a framework to support mobile industry to overcome these
challenges. We first unified the terminology and definitions for usability and
UX attributes in the literature. Then, we created taxonomy of attributes and
sub-attributes. By using the well-known Goal Question Metric (GQM) approach, we
identified a comprehensive set of questions and measures for each attribute
that could be used as a basis for developing measurement instruments. The
framework was evaluated through a case study conducted in a usability research,
development and consultancy company for mobile industry in Sweden