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Lessons learned from transferring software products to India
No full textGlobalization has influenced the way software is developed today, and many
software organizations have started to actively utilize resources from around
the world. However, these endeavors are recognized as very challenging, and
they have attracted a lot of attention in software research in the past decade.
Unlike many other research initiatives, which explore the complexities of
distributed software development activities, the focus of this paper is on
software transfers. Software transfers refer to activities that are moved from
one location to another. The authors draw attention to the lessons learned from
an empirical investigation of two transfer projects conducted at Ericsson. Both
transfers were performed between a site in Sweden and a site in India. The
observations outline a set of generic practices that have been found useful for
transferring software development within a company. It also highlights a number
of challenges to be addressed and a set of corresponding recommendations.
Finally, the paper emphasizes the need to identify software products that are
suitable for transfers and the need to monitor the long-term effects of
transfer
Micro-mechanism of Thin and Laminated Packaging Material during Fracture
No full textFracture path of a polymer coated and uncoated aluminium foil (about 6-7 um) is
followed in a Scanning Electron Microscope. The crack length and applied load
were measured during crack initiation and growth. The specimens’ cross section
were then studied using the optical profilometric method to exam the deformed
surface. For the uncoated Al-foil, no fracture surface can be observed.
Fracture seems to occur through so-called necking. This behaviour was
successfully modelled by a modified strip yield model. It leads to a conclusion
that the crack tip is preceded a substantial plastic zone as compared with the
crack length. The result was then compared to a polymer coated Al-foil. Further
more, similar experimental works were performed on a polymer coated and
uncoated Polypropylene. The results were discussed and compared to the cases
with Al-foil layer
Evaluation and Measurement of Software Process Improvement - A Systematic Literature Review
No full textSoftware Process Improvement (SPI) is a systematic approach to increase the
efficiency and effectiveness of a software development organization and to
enhance software products. OBJECTIVE—This paper aims to identify and
characterize evaluation strategies and measurements used to assess the impact
of different SPI initiatives. METHOD--The systematic literature review includes
148 papers published between 1991 and 2008. The selected papers were classified
according to SPI initiative, applied evaluation strategies and measurement
perspectives. Potential confounding factors interfering with the evaluation of
the improvement effort were assessed. RESULTS--Seven distinct evaluation
strategies were identified, whereas the most common one, "Pre-Post Comparison",
was applied in 49% of the inspected papers. Quality was the most measured
attribute (62%), followed by Cost (41%) and Schedule (18%). Looking at
measurement perspectives, "Project" represents the majority with 66%.
CONCLUSION—The evaluation validity of SPI initiatives is challenged by the
scarce consideration of potential confounding factors, particularly given that
"Pre-Post Comparison" was identified as the most common evaluation strategy,
and the inaccurate descriptions of the evaluation context. Measurements to
assess the short and mid-term impact of SPI initiatives prevail, whereas
long-term measurements in terms of customer satisfaction and return on
investment tend to be less used
Delay performance of cognitive radio networks for point-to-point and point-to-multipoint communications
No full textIn this article, we analyze the packet transmission time in spectrum sharing
systems where a secondary user (SU) simultaneously accesses the spectrum
licensed to primary users (PUs). In particular, under the assumption of an
independent identical distributed Rayleigh block fading channel, we investigate
the effect of the peak interference power constraint imposed by multiple PUs on
the packet transmission time of the SU. Utilizing the concept of timeout, exact
closed-form expressions of outage probability and average packet transmission
time of the SU are derived. In addition, employing the characteristics of the
M/G/1 queuing model, the impact of the number of PUs and their peak
interference power constraint on the stable transmission condition and the
average waiting time of packets at the SU are examined. Moreover, we then
extend the analysis for point-to-point to point-to-multipoint communications
allowing for multiple SUs and derive the related closed-form expressions for
outage probability and successful transmission probability for the best channel
condition. Numerical results are provided to corroborate our theoretical
results and to illustrate applications of the derived closed-form expressions
for performance evaluation of cognitive radio networks
Combinatorial Optimization - Three Applications
No full textCombinatorial optimization is a diverse area of mathematics. It concerns
optimization on feasible regions defined by discrete sets, graphs, hypergraphs,
matroids, etc. . . which all have a large number of applications. They occur in
virtually all domains of human activity since humans always want to do things
easier, faster, consume less resources, etc. . . This
thesis concerns three applied problems within combinatorial optimization.
The first paper generalizes previous optimal upper bounds on the minimum
Euclidean distance for phase-shift keying (PSK) block codes, that are explicit
in the parameters alphabet size, block length and code size. There is a strong
connection between high minimum Euclidean distance and good error-correcting
capabilities. The bounds are generalized in
several respects, such as from codes on symmetric PSK to codes on asymmetric
PSK. They are also generalized to other types of noise than Gaussian, allowing
more efficient block
codes when noise is non-Gaussian. We provide examples of codes on asymmetric
PSK that have higher minimum Euclidean distance than any comparable codes on
symmetric PSK.Several classes of codes are shown to be optimal among codes on
symmetric PSK since their Euclidean distance coincides with the bound.
The second paper considers a parallel computer system with m identical
computers,where we study optimal performance precaution for one possible
computer crash. We anticipate that some computer may crash, and restrict the
cost in such a situation. How costly is such a precaution when no crash occurs?
We set a restriction that the completion time of a parallel program after a
crash is at most a factor r + 1 larger than if we use an optimal allocation
with m - 1 computers. This is an r-dependent restriction of the set of
allocations of a program. Then the worst-case ratio of the optimal r-dependent
completion time in the case of no crash and the unrestricted optimal completion
time defines a function
f(r,m). In the paper we establish upper and lower bounds of the worst-case cost
function f(r,m) and characterize worst-case programs.
The third paper considers the problem of Map Matching (MM), i.e. matching time
and location measurements of a vehicle to a route in a road network. The paper
presents a
probabilistic algorithm for MM based on a second order hidden Markov model
(HMM), as opposed to first order HMMs which are usually used. This allows a
more detailed analysis
of the data while preserving algorithmic complexity O(n). Both measurement
densities and transition probabilities are determined with respect to
Kolmogorov's third axiom, which in
this context implies that the probabilities are additive over a partition of a
road segment
The rise of social product development
No full textThe aim of the paper is to discuss the rising potential of social software to
increase the knowledge management capabilities of virtual product development
teams. It presents six fundamental transitions, elaborated from the empirical
findings, which justify the rise of a more bottom-up, social creation and
sharing of engineering knowledge in the virtual organisation. The study
suggests that traditional engineering knowledge management approaches alone are
not sufficient to support development activities in the virtual organisation,
and that such teams display an increasing demand for social, comparatively
lightweight and remixable platforms for bottom-up, social creation and sharing
of knowledge
Accessibility and Self Archiving of Conference Articles: A Study on a Selection of Swedish Institutional Repositories
No full textThe main purpose of this project has been to examine the accessibility of
refereed conference articles and the OA- and publishing policies of conferences
in order to in this way elucidate different aspects concerning self-archiving
in Swedish institutional repositories. For this purpose, the project
participants have examined a number of conferences and references to conference
articles via their institutional repositories during a specific time period and
described these from the perspective of a common scheme. The study has showed
that the local institutional repositories fill an important role to make
conference publications visible. We have found that ca. 50 % of the conference
papers can be published as postprints in our institutional repositories. We
have noticed that ca. 15% or the studied conference articles are not available
at all. It is, therefore, of great importance to use local institutional
repositories as a publishing channel, not only for primary published material
such as dissertations and reports, but also as a source for finding these
conference articles “without a home”. Between 20-25 % of the examined articles
were found in some type of OA archive; ca. half of these were found in one of
the project participants’ own institutional repositories. This indicates that
the publishing database of respective higher education institution is an
important factor for open accessibility. Ca. 10% of the conferences in the
study had an explicit OA policy or expressed such a policy by openly making
conference articles accessible on their conference sites. A big problem when it
comes to self-archiving of conference articles is the lack of information about
OA policy. The landscape of conference publishing is complex and the
self-archiving of documents from conferences is very time-consuming. Above all,
we would wish a policy resource for conferences similar to the SHERPA/RoMEO. At
present, however, there is no other alternative than scrutinizing the
conferences’ copyright information to the authors and from this attempt to draw
conclusions about possible self-archiving
Selected Algorithms of Computational Intelligence in Gastric Cancer Decision Making
No full textDue to the latest research the subject of Computational Intelligence has been
divided into five main regions, namely, neural networks, evolutionary
algorithms, swarm intelligence, immunological systems and fuzzy systems.
Our attention has been attracted by the possibilities of medical applications
provided by immunological computation algorithms. Immunological computation
systems are based on immune reactions of the living organisms in order to
defend the bodies from pathological substances. Especially, the mechanisms of
the T-cell reactions to detect strangers have been converted into artificial
numerical algorithms.
Immunological systems have been developed in scientific books and reports
appearing during the two last decades. The basic negative selection algorithm
NS was invented by Stefanie Forrest to give rise to some technical
applications. We can note such applications of NS as computer virus detection,
reduction of noise effect, communication of autonomous agents or identification
of time varying systems. Even a trial of connection between a computer and
biological systems has been proved by means of immunological computation.
Hybrids made between different fields can provide researchers with richer
results; therefore associations between immunological systems and neural
networks have been developed as well.
In the current chapter we propose another hybrid between the NS algorithm and
chosen solutions coming from fuzzy systems. This hybrid constitutes the own
model of adapting the NS algorithm to the operation decisions “operate” contra
“do not operate” in gastric cancer surgery. The choice between two
possibilities to treat patients is identified with the partition of a decision
region in self and non-self, which is similar to the action of the NS
algorithm. The partition is accomplished on the basis of patient data
strings/vectors that contain codes of states concerning some essential
biological markers. To be able to identify the strings that characterize the
“operate” decision we add the own method of computing the patients’
characteristics as real values. The evaluation of the patients’ characteristics
is supported by inserting importance weights assigned to powerful biological
indices taking place in the operation decision process. To compute the weights
of importance the Saaty algorithm is adopted
Factors influencing quality of experience of commonly-used mobile applications
No full textIncreasingly, we use mobile applications and services in our daily life
activities, to support our needs for information, communication or leisure.
However, user acceptance of a mobile application depends on at least two
conditions; the application’s perceived experience and the appropriateness of
the application to the user’s context and needs. Yet, we have a weak
understanding of a mobile user’s Quality of Experience (QoE) and the factors
influencing it. This paper presents 4 week long, 29 Android phone users study,
where we collected both QoE and underlying network’s Quality of Service (QoS)
measures through a combination of user,
application and network data on the user’s phones. We aimed to derive and
improve the understanding of users’ QoE for a set of widely used mobile
applications in users’ natural environments and different daily context. We
present data acquired in the study and discuss implications for mobile
applications design
ICT, Learnin Objects and Activity Theory
No full textDifferent research traditions describe the implied rather than acknowledged
dispute between individual agency and collective activity. The ability of an
individual to take action has a positive effect on the functioning of a social
system. Initiative is a praised self-controlled quality and inter-subjective
relations between people and reactions to another person’s input are crucial
for the main activity. I this chapter I draw on experiences of digital software
deployed for facilitating teaching and learning