Blekinge Institute of Technology
Electronic Research Archive - Blekinge Tekniska HögskolaNot a member yet
1855 research outputs found
Sort by
Enhancing supply chain collaboration in automotive industry by value driven simulation
No full textThis paper presents a computer-based approach for conceptual design that aims
to enhance collaborative supply chain development in the automotive sector when
dealing with product-service development or radical innovations. The focus of
the research has been to design a simulation approach that will enable
designers and managers to simulate and evaluate the value of different design
options for the different stakeholders involved in the development process and
to have insights about the implications between business model innovation and
the engineered aspects of the solutions early in the conceptual phase.
The approach is presented using a case study within the current project, after
following a team responsible for the car cockpit. Four possible scenario have
been simulated and evaluated using a commercial simulation software.
The main advantage of the proposed approach is to enhance the awareness among
designers and managers of the value of different design options, and allow them
to explore further how business and design aspects profoundly affect each
other, in order to support early decision-making in the design process
Real-time landscape-size convective clouds simulation
No full textWe introduce Lagrangian framework for the cloud physics and rendering at
landscape size. The use of Lagrangian formalism, aerology physics, and
separation of environment from the dynamics, brings more robustness, offers
meaningful
high-level handles for user control - environment profile and
evolution, cloud base and top
Gender Budgeting, Human Resources, Organisational Culture -Development of Methods
No full textGENISLAB, is a four year project (2011 - 2014) within the 7th Framework
Programme for research and technology. The aim of the project is to promote
organizational change in six European scientific organizations. Each partner
develops its own Tailored Action Plan based on three dimensions, Gender
Budgeting, Human Resources (HR) Management and Gender and Organisational
Culture and Stereotypes. This report presents results of quantitative and
qualitative data on Gender Budgeting and HR management as well as comments on
organizational culture
VLQoE: Video QoE instrumentation on the smartphone
No full textThe usage of network-demanding applications is growing rapidly such as video
streaming on mobile terminals. However, network and/or service providers might
not guarantee the perceived quality for video streaming that demands high
packet transmission rate. In order to satisfy the user expectations and to
minimize user churn, it is important for network operators to infer the
end-user perceived quality in video streaming. Today, the most reliable method
to obtain end-user perceived quality is through subjective tests, and the
preferred location is the user interface as it is the closest point of
application to the end-user. The end-user perceived quality on video streaming
is highly influenced by occasional freezes; technically the extraordinary time
gaps between two consecutive pictures that are displayed to the user, i.e.,
high inter-picture time. In this paper, we present a QoE instrumentation for
video streaming, VLQoE. We added functionality to the VLC player to record a
set of metrics from the user interface, application-level, network-level, and
from the available sensors of the device. To the best of our knowledge, VLQoE
is the first tool of its kind that can be used in user experiments for video
streaming. By using the tool, we present a two state model based on the
inter-picture time, for the HTTP- and RTSP-based video streaming via 3.5G.
Next, we studied the influence of inter-picture time on the user perceived
quality through out a user study. We investigated the minimum user perceived
inter-picture time, and the user response time
Manufacturing knowledge: Going from production of things to designing value in use
No full textA new vision in manufacturing is to develop product-service integrated value
solutions. Today, few firms have fully realized this vision because they are
not able to support the reasoning in the early stages of design. The purpose of
this paper is to discuss engineers' cognitive challenge when replacing the core
product rationale with value logic. The paper problematizes engineering design
by dividing knowledge into the categories technically constructed (explicit)
and socially constructed (tacit). In doing so, this study contributes the
assumed effects of a perspective shift that could guide the development of
computational tools
Algorithms for Automated Live Migration of Virtual Machines
No full textWe present two strategies to balance the load in a system with multiple virtual
machines (VMs) through automated live migration. When the push strategy is
used, overloaded hosts try to migrate workload to less loaded nodes. On the
other hand, when the pull strategy is employed, the light-loaded hosts take the
initiative to offload overloaded nodes.
The performance of the proposed strategies was evaluated through simulations.
We have discovered that the strategies complement each other, in the sense that
each strategy comes out as “best” under different types of workload. For
example, the pull strategy is able to quickly re-distribute the load of the
system when the load is in the range low-to-medium, while the push strategy is
faster when the load is medium-to-high.
Our evaluation shows that when adding or removing a large number of virtual
machines in the system, the “best” strategy can re-balance the system in 4–15
minutes
Policy guidelines for open access and data dissemination and preservation
No full textThe RECODE project identified two overarching issues that are inhibiting
take-up of policies related to open access to research data: a lack of a
coherent open data ecosystem; and a lack of attention to the specificity of
research practices, processes and forms of data collections. Against this
background, the report provides policy recommendations on open access to
research data targeted at key stakeholders in promoting open access: research
funders; data managers; research institutions; and publishers. These
recommendations will assist the above stakeholders in furthering the goals of
open access to research data in each of their organizations and networks.
Recommendations include both overarching and stakeholder-specific ones as
suggestions to address and attend to these two issues by building on or
learning from existing experience. In doing so, RECODE recognises that in some
situations it is appropriate to build consensus and transfer good practice
across disciplines and stakeholder groups, while in others it is appropriate to
enable and support specific groups to maintain their particularity in relation
to disseminating, preserving and re-using research data. In addition, for each
stakeholder group good practice examples are provided that can serve as
“models” for providing open access to research data. Finally, the
recommendations and good practice examples will reduce “costs” associated with
providing open access, as stakeholders do not need to develop their own
expertise, but can use this information as a foundation to develop their own
policies, support actions and initiatives
Performance Analysis of a Cognitive Radio Network with a Buffered Relay
No full textIn this paper, we analyze the packet transmission time in a cognitive
cooperative radio network (CCRN) where a secondary transmitter (SU-Tx) sends
packets to a secondary receiver (SU-Rx) through the help of a secondary relay
(SR). In particular, we assume that the SU-Tx and SR are subject to the joint
constraint of the timeout probability of the primary user (PU) and the peak
transmit powers of the secondary users. On this basis, we investigate the
impact of the transmit power of the PUs and channel mean powers on the packet
transmission time of the CCRN. Utilizing the concept of timeout, adaptive
transmit power allocation policies for the SU-Tx and SR are considered. More
importantly, analytical expressions for the endto- end throughput, end-to-end
packet transmission time, and stable condition for the SR operation are
obtained. Our results indicate that the second hop of the considered CCRN is
not a bottleneck if the channel mean powers of the interference links of the
networks are small and the SR peak transmit power is set to a high value
Family members of older persons with multi-morbidity and their experiences of case managers in Sweden: an interpretive phenomenological approach
No full textBackground: Family members of older persons (75+) with multi-morbidity are
likely to benefit from utilising case management services performed by case
managers. However, research has not yet explored their experiences of case
managers.
Objectives: The aim of the study was to deepen the understanding of the
importance of case managers to family members of older persons (75+) with
multi-morbidity.
Design: The study design was based on an interpretive phenomenological approach.
Method: Data were collected through individual interviews with 16 family
members in Sweden. The interviews were analysed by means of an interpretive
phenomenological approach.
Results: The findings revealed one overarching theme: “Helps to fulfil my unmet
needs”, based on three sub-themes: (1) “Helps me feel secure – Experiencing a
trusting relationship”, (2) “Confirms and strengthens me – Challenging my sense
of being alone” and (3) “Being my personal guide – Increasing my competence”.
Conclusion and discussion: The findings indicate that case managers were able
to fulfil unmet needs of family members. The latter recognised the importance
of case managers providing them with professional services tailored to their
individual needs. The findings can contribute to the improvement of case
management models not only for older persons but also for their family members
On the Performance of Underlay Cognitive Radio Networks with Interference Constraints and Relaying
No full textEfficiently allocating the scarce and expensive radio resources is a key
challenge for advanced radio communication systems. To this end, cognitive
radio (CR) has emerged as a promising solution which can offer considerable
improvements in spectrum utilization. Furthermore, cooperative communication is
a concept proposed to obtain spatial diversity gains through relays without
requiring multiple antennas. To benefit from both CR and cooperative
communications, a combination of CR networks (CRNs) with cooperative relaying
referred to as cognitive cooperative relay networks (CCRNs) has recently been
proposed. CCRNs can better utilize the radio spectrum by allowing the secondary
users (SUs) to opportunistically access spectrum, share spectrum with primary
users (PUs), and provide performance gains offered by cooperative relaying. In
this thesis, a performance analysis of underlay CRNs and CCRNs in different
fading channels is provided based on analytical expressions, numerical results,
and simulations. To allocate power in the CCRNs, power allocation policies are
proposed which consider the peak transmit power limit of the SUs and the outage
probability constraint of the primary network. Thus, the impact of multiuser
diversity, peak transmit power, fading parameters, and modulation schemes on
the performance of the CRNs and CCRNs can be analyzed.
The thesis is divided into an introduction and five research parts based on
peer-reviewed conference papers and journal articles. The introduction provides
fundamental background on spectrum sharing systems, fading channels, and
performance metrics. In the first part, a basic underlay CRN is analyzed where
the outage probability and the ergodic capacity of the network over general
fading channels is derived. In the second part, the outage probability and the
ergodic capacity of an underlay CRN are assessed capturing the effect of
multiuser diversity on the network subject to Nakagami-m fading. Considering
the presence of a PU transmitter (PU-Tx), a power allocation policy is derived
and utilized for CRN performance analysis under Rayleigh fading. In the third
part, the impact of multiple PU-Txs and multiple PU receivers (PU-Rxs) on the
outage probability of an underlay CCRN is studied. The outage constraint at the
PU-Rx and the peak transmit power constraint of the SUs are taken into account
to derive the power allocation policies for the SUs. In the fourth part,
analytical expressions for the outage probability and symbol error probability
for CCRNs are derived where signal combining schemes at the SU receiver (SU-Rx)
are compared. Finally, the fifth part applies a sleep/wake-up strategy and the
min(N; T) policy to an underlay CRN. The SUs of the network operate as wireless
sensor nodes under Nakagami-m fading. A power consumption function of the CRN
is derived. Further, the impact of M/G/1 queue and fading channel parameters on
the power consumption is assessed