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Web-Enabled Customer Involvement in Innovation Activities : a Firm's Perspective
No full textCustomer involvement in innovation activities is a common practice among
companies in most industries. It has been widely researched by scholars to
demonstrate its risks and advantages. Yet, the growing importance and
recognition of the Internet are transforming the scope, boundaries, and
dynamics of interactions among firms and customers. Progressing information and
communication technologies (ICTs) (including the Internet) enable faster,
cheaper, and more efficient collaboration. The demonstrated benefits of using
various web-based methods for customer involvement in innovation activities
have encouraged companies to adopt a new approach. Despite this, there is a
lack of knowledge about associated challenges. In addition, prior research was
unable to provide empirical evidence of the claimed benefits ensuing from
web-enabled customer involvement. As a result, companies may experience
unforeseen difficulties and may not be able to achieve what they expect from
their implementation of web-based methods.
This thesis aims to address this research gap by exploring web-enabled customer
involvement from a firm’s perspective. The overall purpose of this dissertation
is to increase the understanding of web-enabled customer involvement in
innovation activities by exploring its use and its impact on firms’ innovation,
as well as management competences needed for its efficient realization. The
thesis draws on the concept of absorptive capacity and includes four empirical
studies from various industries.
The adoption levels of a wide range of web-based methods were identified and
compared with the findings of the previous study, thereby uncovering
interesting changes in their popularity, as well as differences in adoption
among companies in various industries. The empirical findings of this thesis
show that web-based methods increase a company’s probability to introduce
service innovations. Three types of challenges related to different types of
web-based methods were identified and verified. It was also possible to
identify corresponding management practices to handle these challenges. The
management practices form three firm competences, constituting a specific
absorptive capacity. It was proved that all dimensions of this specific
absorptive capacity are needed for successful and effective customer
involvement.
Insights of this thesis contribute to increasing the understanding of
web-enabled customer involvement. Therefore, the thesis provides companies with
empirically verified knowledge that is necessary to make decisions about the
implementation and management of web-enabled customer involvement
Realistic Package Opening Simulations : An Experimental Mechanics and Physics Based Approach
No full textA finite element modeling strategy targeting package opening simulations is the
final goal with this work. The developed simulation model will be used to
proactively predict the opening compatibility early in the development process
of a new opening device and/or a new packaging material. To be able to create
such a model, the focus is to develop a combined and integrated
physical/virtual test procedure for mechanical characterization and calibration
of thin packaging materials. Furthermore, the governing mechanical properties
of the materials involved in the opening performance needs to be identified and
quantified with experiments. Different experimental techniques complemented
with video recording equipment were refined and utilized during the course of
work. An automatic or semi-automatic material model parameter identification
process involving video capturing of the deformation process and inverse
modeling is proposed for the different packaging material layers. Both an
accurate continuum model and a damage material model, used in the simulation
model, were translated and extracted from the experimental test results.
The results presented show that it is possible to select constitutive material
models in conjunction with continuum material damage models, adequately
predicting the mechanical behavior of intended failure in thin laminated
packaging materials. A thorough material mechanics understanding of individual
material layers evolution of microstructure and the micro mechanisms involved
in the deformation process is essential for appropriate selection of numerical
material models. Finally, with a slight modification of already available
techniques and functionalities in the commercial finite element software
AbaqusTM it was possible to build the suitable simulation model.
To build a realistic simulation model an accurate description of the
geometrical features is important. Therefore, advancements within the
experimental visualization techniques utilizing a combination of video
recording, photoelasticity and Scanning Electron Microscopy (SEM) of the micro
structure have enabled extraction of geometries and additional information from
ordinary standard experimental tests. Finally, a comparison of the experimental
opening and the virtual opening, showed a good correlation with the developed
finite element modeling technique.
The advantage with the developed modeling approach is that it is possible to
modify the material composition of the laminate. Individual material layers can
be altered and the mechanical properties, thickness or geometrical shape can be
changed. Furthermore, the model is flexible and a new opening device i.e.
geometry and load case can easily be adopted in the simulation model.
Therefore, this type of simulation model is a useful tool and can be used for
decision support early in the concept selection of development projects
Software Quality Evaluation for Evolving Systems in Distributed Development Environments
No full textContext: There is an overwhelming prevalence of companies developing software
in global software development (GSD) contexts. The existing body of knowledge,
however, falls short of providing comprehensive empirical evidence on the
implication of GSD contexts on software quality for evolving software systems.
Therefore there is limited evidence to support practitioners that need to make
informed decisions about ongoing or future GSD projects.
Objective: This thesis work seeks to explore changes in quality, as well as to
gather confounding factors that influence quality, for software systems that
evolve in GSD contexts.
Method: The research work in this thesis includes empirical work that was
performed through exploratory case studies. This involved analysis of
quantitative data consisting of defects as an indicator for quality, and
measures that capture software evolution, and qualitative data from company
documentations, interviews, focus group meetings, and questionnaires. An
extensive literature review was also performed to gather information that was
used to support the empirical investigations.
Results: Offshoring software development work, to a location that has employees
with limited or no prior experience with the software product, as observed in
software transfers, can have a negative impact on quality. Engaging in long
periods of distributed development with an offshore site and eventually handing
over all responsibilities to the offshore site can be an alternative to
software transfers. This approach can alleviate a negative effect on quality.
Finally, the studies highlight the importance of taking into account the GSD
context when investigating quality for software that is developed in globally
distributed environments. This helps with making valid inferences about the
development settings in GSD projects in relation to quality.
Conclusion: The empirical work presented in this thesis can be useful input for
practitioners that are planning to develop software in globally distributed
environments. For example, the insights on confounding factors or mitigation
practices that are linked to quality in the empirical studies can be used as
input to support decision-making processes when planning similar GSD projects.
Consequently, lessons learned from the empirical investigations were used to
formulate a method, GSD-QuID, for investigating quality using defects for
evolving systems. The method is expected to help researchers avoid making
incorrect inferences about the implications of GSD contexts on quality for
evolving software systems, when using defects as a quality indicator. This in
turn will benefit practitioners that need the information to make informed
decisions for software that is developed in similar circumstances
A No-Reference Bitstream-based Perceptual Model for Video Quality Estimation of Videos Affected by Coding Artifacts and Packet Losses
No full textIn this work, we propose a No-Reference (NR) bitstream-based model for
predicting the quality of H.264/AVC video sequences, aeffected by both
compression artifacts and transmission impairments. The concept of the article
is based on a feature extraction procedure, where a large number of features
are calculated from the impaired bitstream. Many of the features are mostly
proposed in this work, while the specificc set of the features as a whole is
applied for the first time for making NR video quality predictions. All
feature observations are taken as input to the Least Absolute Shrinkage and
Selection Operator (LASSO) regression method. LASSO indicates the most
important features, and using only them, it is able to estimate the Mean
Opinion Score (MOS) with high accuracy. Indicatively, we point out that only 13
features are able to produce a Pearson Correlation Coefficient of 0:92 with
the MOS. Interestingly, the performance statistics we computed in order to
assess our method for predicting the Structural Similarity Index and the Video
Quality Metric are equally good. Thus, the obtained experimental results verifi
ed the suitability of the features selected by LASSO as well as the ability of
LASSO in making accurate predictions through sparse modeling
In press: A Cross-Layer Optimized Scheme and Its Application in Mobile Multimedia Networks With QoS Provision
No full textTo cope with the rapid growth of multimedia applications that requires dynamic
levels of quality of service (QoS), cross-layer (CL) design, where multiple
protocol layers are jointly combined, has been considered to provide diverse
QoS provisions for mobile multimedia networks. However, there is a lack of a
general mathematical framework to model such CL scheme in wireless networks
with different types of multimedia classes. In this paper, to overcome this
shortcoming, we therefore propose a novel CL design for integrated
real-time/non-real-time traffic with strict preemptive priority via a
finite-state Markov chain. The main strategy of the CL scheme is to design a
Markov model by explicitly including adaptive modulation and coding at the
physical layer, queuing at the data link layer, and the bursty nature of
multimedia traffic classes at the application layer. Utilizing this Markov
model, several important performance metrics in terms of packet loss rate,
delay, and throughput are examined. In addition, our proposed framework is
exploited in various multimedia applications, for example, the end-to-end
real-time video streaming and CL optimization, which require the priority-based
QoS adaptation for different applications. More importantly, the CL framework
reveals important guidelines as to optimize the network performance
An Organic View of Prototyping in Information System Development
No full textThis paper presents an organic view of prototyping for managing dynamic factors
involved in evolutionary design of information systems (IS). Those dynamic
factors can be caused by, for example, continuing suggestions from users,
changes in the technologies, and users-designers learning related stepwise
progresses. Expanding the evolutionary prototyping to ‘start small and grow’,
the organic view of prototyping proposes two prerequisites to do so, namely 1)
a sustainable and adaptive ‘embryo’ – an organic structure of the future
system, and 2) an embedded learning and feedback management that the actors of
the system (users, designers, decision makers, administrators) can communicate
with each other. An example of eHealth system design demonstrates how the
prerequisites can be implemented
Operationalization of lean thinking through value stream mapping with simulation and FLOW
No full textBackground: The continued success of Lean thinking beyond manufacturing has led
to an increasing interest to utilize it in software engineering (SE). Value
Stream Mapping (VSM) had a pivotal role in the operationalization of Lean
thinking. However, this has not been recognized in SE adaptations of Lean.
Furthermore, there are two main shortcomings in existing adaptations of VSM for
an SE context. First, the assessments for the potential of the proposed
improvements are based on idealistic assertions. Second, the current VSM
notation and methodology are unable to capture the myriad of significant
information flows, which in software development go beyond just the schedule
information about the flow of a software artifact through a process.
Objective: This thesis seeks to assess Software Process Simulation Modeling
(SPSM) as a solution to the first shortcoming of VSM. In this regard,
guidelines to perform simulation-based studies in industry are consolidated,
and the usefulness of VSM supported with SPSM is evaluated. To overcome the
second shortcoming of VSM, a suitable approach for capturing rich information
flows in software development is identified and its usefulness to support VSM
is evaluated. Overall, an attempt is made to supplement existing guidelines for
conducting VSM to overcome its known shortcomings and support adoption of Lean
thinking in SE. The usefulness and scalability of these proposals is evaluated
in an industrial setting.
Method: Three literature reviews, one systematic literature review, four
industrial case studies, and a case study in an academic context were conducted
as part of this research.
Results: Little evidence to substantiate the claims of the usefulness of SPSM
was found. Hence, prior to combining it with VSM, we consolidated the
guidelines to conduct an SPSM based study and evaluated the use of SPSM in
academic and industrial contexts. In education, it was found to be a useful
complement to other teaching methods, and in the industry, it triggered useful
discussions and was used to challenge practitioners’ perceptions about the
impact of existing challenges and proposed improvements. The combination of VSM
with FLOW (a method and notation to capture information flows, since existing
VSM adaptions for SE are insufficient for this purpose) was successful in
identifying challenges and improvements related to information needs in the
process. Both proposals to support VSM with simulation and FLOW led to
identification of waste and improvements (which would not have been possible
with conventional VSM), generated more insightful discussions and resulted in
more realistic improvements.
Conclusion: This thesis characterizes the context and shows how SPSM was
beneficial both in the industrial and academic context. FLOW was found to be a
scalable, lightweight supplement to strengthen the information flow analysis in
VSM. Through successful industrial application and uptake, this thesis provides
evidence of the usefulness of the proposed improvements to the VSM activities
On the Performance Assessment of Advanced Cognitive Radio Networks
No full textDue to the rapid development of wireless communications together with the
inflexibility of the current spectrum allocation policy, radio spectrum becomes
more and more exhausted. One of the critical challenges of wireless
communication systems is to efficiently utilize the limited frequency resources
to be able to support the growing demand of high data rate wireless services.
As a promising solution, cognitive radios have been suggested to deal with the
scarcity and under-utilization of radio spectrum. The basic idea behind
cognitive radios is to allow unlicensed users, also called secondary users
(SUs), to access the licensed spectrum of primary users (PUs) which improves
spectrum utilization. In order to not degrade the performance of the primary
networks, SUs have to deploy interference control, interference mitigating, or
interference avoidance techniques to minimize the interference incurred at the
PUs. Cognitive radio networks (CRNs) have stimulated a variety of studies on
improving spectrum utilization. In this context, this thesis has two main
objectives. Firstly, it investigates the performance of single hop CRNs with
spectrum sharing and opportunistic spectrum access. Secondly, the thesis
analyzes the performance improvements of two hop cognitive radio networks when
incorporating advanced radio transmission techniques.
The thesis is divided into three parts consisting of an introduction part and
two research parts based on peer-reviewed publications. Fundamental background
on radio propagation channels, cognitive radios, and advanced radio
transmission techniques are discussed in the introduction. In the first
research part, the performance of single hop CRNs is analyzed. Specifically,
underlay spectrum access using M/G/1/K queueing approaches is presented in Part
I-A while dynamic spectrum access with prioritized traffics is studied in Part
I-B. In the second research part, the performance benefits of integrating
advanced radio transmission techniques into cognitive cooperative radio
networks (CCRNs) are investigated. In particular, opportunistic spectrum access
for amplify-and-forward CCRNs is presented in Part II-A where collaborative
spectrum sensing is deployed among the SUs to enhance the accuracy of spectrum
sensing. In Part II-B, the effect of channel estimation error and feedback
delay on the outage probability and symbol error rate (SER) of multiple-input
multiple-output CCRNs is investigated. In Part II-C, adaptive modulation and
coding is employed for decode-and-forward CCRNs to improve the spectrum
efficiency and to avoid buffer overflow at the relay. Finally, a hybrid
interweave-underlay spectrum access scheme for a CCRN is proposed in Part II-D.
In this work, the dynamic spectrum access of the PUs and SUs is modeled as a
Markov chain which then is utilized to evaluate the outage probability, SER,
and outage capacity of the CCRN
Feasibility of using existing open access networks to support the harmonization of open access
No full textIn this report we identify and assess different options for bringing together
and mobilizing relevant stakeholders in the open access arena. This builds on
previous work done in the RECODE project about the open access stakeholder
ecosystem, the barriers and the enablers for open access to research data as
well as on the RECODE overarching policy recommendations set out in the RECODE
work package 5. We have identified a sample of existing networks and
organizations to determine whether they are able to meet stakeholder needs and
mobilization objectives for open access, data preservation, dissemination and
use, and what these organizations can or must do in order to better mobilize
stakeholders in order to meet the policy recommendations.
We have identified not only examples of good practice but also the barriers not
addressed by any currently available structures or organizations. While there
are many forces striving to make data sharing common practice, there is still a
lack of an overarching, international initiative to implement necessary
requirements for making data sharing a truly international community asset.
Within the European community the prerequisites and the ambitions are very
different among the member states. Even amongst those countries where open
access has long been on the agenda, there remain issues and barriers to be
addressed. For example, training is needed in most of the stakeholder groups;
investment in infrastructure building and funding is required in most
institutions dealing with open access to research data; much work remains to be
done to convince researchers that sharing data is a good idea. These are just a
few of the obstacles that still need attention despite good, on-going efforts
by individuals, organizations and states