@inproceedings {INPROC-2007-48,
author = {Marcus Handte and Klaus Herrmann and Gregor Schiele and Christian Becker and Kurt Rothermel},
title = {{Automatic Reactive Adaptation of Pervasive Applications}},
booktitle = {Proceedings of ICPS'07: IEEE International Conference on Pervasive Services},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {214--222},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2007},
keywords = {adaptivity, components, mobility, optimization},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-48/INPROC-2007-48.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive Computing envisions seamless and distraction-free support for
everyday tasks through distributedapplications that leverage the resources of
the users' environment. Due to the mobility of users and devices, applications
need to adapt continuously to their changing execution environment. Therefore,
developers need a suitable framework in order to efficiently create adaptive
applications. In this paper, we present and evaluate our approach to adapting a
pervasive computing application to changes during its execution. This work is
based on the minimal component system PCOM and on an algorithm to fully
automate the initial configuration of a componentbased application which we
have presented in earlier work. The contribution of this paper is threefold.
First, we describe a number of modifications to the component model that are
required to enable fully automatic adaptation. Secondly, we propose a simple
yet powerful cost model to capture the complexity of specific adaptations.
Thirdly, we describe an online optimization heuristic that extends our
distributed configuration algorithm in order to choose to a low-cost
configuration whenever the current configuration of a pervasive application
requires adaptation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-48&engl=0}
}
@inproceedings {INPROC-2007-13,
author = {Marcus Handte and Klaus Herrmann and Gregor Schiele and Christian Becker},
title = {{Supporting Pluggable Configuration Algorithms in PCOM}},
booktitle = {Perware Workshop at 5th IEEE International Conference on Pervasive Computing and Communications (PerCom)},
address = {New York, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {472--476},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
language = {Englisch},
cr-category = {D.2.11 Software Engineering Software Architectures,
D.1.2 Automatic Programming},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2007-13/INPROC-2007-13.pdf,
http://dx.doi.org/10.1109/PERCOMW.2007.111},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive Computing envisions distributed applications that optimally leverage
the resources present in their ever-changing execution environment. To ease the
development of pervasive applications, we have created a pervasive component
system (PCOM). PCOM automates the configuration and runtime adaptation of a
component-based application using a builtin distributed configuration
algorithm. In this paper, we present an architectural extension that allows
switching between different algorithms. This enables PCOM to dynamically select
an algorithm that suits the computational resources present in an environment.
To validate the extended architecture, we compare the overheads of a
distributed and a centralized configuration algorithm in two different
environments.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-13&engl=0}
}
@inproceedings {INPROC-2007-12,
author = {Gregor Schiele and Marcus Handte and Christian Becker},
title = {{Good Manners for Pervasive Computing - An Approach Based on the Ambient Calculus}},
booktitle = {WIP Track at 5th IEEE International Conference on Pervasive Computing and Communications (PerCom)},
address = {New York, USA},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {589--593},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2007},
language = {Englisch},
cr-category = {D.2.7 Software Engineering Distribution, Maintenance, and Enhancement},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {When people interact, they follow distinct rules that coordinate the order of
speech, who opens doors, whom and how to greet, and many things more. Such a
social codex depends on the milieu -- or ambience -- people are acting in.
People breaking the codex are either considered badly educated or foreigners to
the ambience -- sometimes even both. In Pervasive Computing a multitude of
applications is expected to populate our environment and to follow objects and
users throughout their daily journey. Consequently, we will need a new codex --
or manners -- for Pervasive Computing applications that controls the
interaction between applications. Such a codex will have to incorporate our
existing codices as well as technical aspects. In this work in progress paper
we present an approach to extend our prior work on Pervasive Computing system
support by specifying interdependencies of applications based on the ambient
calculus. This allows specifying and technically enforcing ``manners'' for
Pervasive Computing applications.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-12&engl=0}
}
@inproceedings {INPROC-2006-72,
author = {Stephan Urbanski and Christian Becker and Kurt Rothermel},
title = {{Sentient Processes - Process-based Applications in Pervasive Computing}},
booktitle = {WIP Track at 4th IEEE Conference on Pervasive Computing and Communications (PerCom)},
editor = {IEEE},
address = {Pisa, Italy},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--4},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2006},
language = {Englisch},
cr-category = {D.2.3 Software Engineering Coding Tools and Techniques,
D.2.11 Software Engineering Software Architectures},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Users' tasks are typically a sequence of steps. Today, the goal of pervasive
computing applications - to support users in their tasks by using context
information - is only partially met as applications supported by current
infrastructures focus on individual steps instead of supporting the
coordination of the whole sequence. In this paper, we present an approach for
supporting multi-step user tasks by using a process-based application model,
called sentient processes. Along with the model, the paper introduces the
design of an execution engine for such processes.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-72&engl=0}
}
@inproceedings {INPROC-2006-42,
author = {Abdelmajid Khelil and Pedro Jos{\'e} Marr{\'o}n and Christian Becker and Kurt Rothermel},
title = {{Hypergossiping: A Generalized Broadcast Strategy for MANETs}},
booktitle = {Elsevier Ad Hoc Networks Journal},
publisher = {Elsevier},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {August},
year = {2006},
keywords = {mobile ad hoc network (MANET); adaptive broadcast; network partitioning},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Broadcasting is a commonly used communication primitive needed by many
applications and protocols in mobile ad hoc networks (MANET). Unfortunately,
most broadcast solutions are tailored to one class of MANETs with respect to
node density and node mobility and are unlikely to operate well in other
classes. In this paper, we introduce hypergossiping, a novel adaptive broadcast
algorithm that combines two strategies. Hypergossiping uses adaptive gossiping
to efficiently distribute messages within single network partitions and
implements an efficient heuristic to distribute them across partitions.
Simulation results in ns-2 show that hypergossiping operates well for a broad
range of MANETs with respect to node densities, mobility levels and network
loads.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-42&engl=0}
}
@inproceedings {INPROC-2006-13,
author = {Tobias Drosdol and Dominique Dudkowski and Christian Becker and Kurt Rothermel},
title = {{Efficient Indexing of Symbolic Location Information}},
booktitle = {Proceedings of the Second Workshop on Context Awareness for Proactive Systems (CAPS 2006)},
address = {Kassel, Germany},
publisher = {---},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2006},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
E.2 Data Storage Representations,
H.3 Information Storage and Retrieval},
contact = {Tobias.Drosdol@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Providing context-awareness in future applications demands for accurate
information about the positions of a potentially large number of mobile
objects. This requires location management systems that are capable of coping
with a huge amount of such highly dynamic data. To efficiently retrieve
relevant information, e.g., all objects located inside a given area, these
systems must utilize adequate index structures. In the past, suitable indexes
have been explored for geometric representations of location information only.
The contribution of this paper is a generic index structure for the efficient
management of symbolic location information. Based on different index variants
an adaptive approach is derived that can be adjusted to accommodate different
ratios of update and retrieval load. Our experimental results show how this can
significantly increase the overall performance of a location management system.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-13&engl=0}
}
@inproceedings {INPROC-2006-08,
author = {Torben Weis and Marcus Handte and Mirko Knoll and Christian Becker},
title = {{Customizable Pervasive Applications}},
booktitle = {Proceedings of 4th IEEE International Conference on Pervasive Computing and Communications},
publisher = {-},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--6},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2006},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks,
D.2 Software Engineering,
D.3 Programming Languages},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Human behavior and housing resist every stan-dardization effort. Many aspects
such as different technical equipment, furniture, and usage patterns make our
surroundings as individual as ourselves. Thus, the personalization of pervasive
applications is a fundamental requirement. To enable the development of custom
pervasive applications, we propose a soft-ware development process. This
process is based on the successful process for modern desktop applica-tions.
There, developers create extensible applications and components. Customizers
use the resulting arti-facts to develop custom applications. Finally, users
configure applications to their individual needs by adjusting predefined
settings. To adopt this process for Pervasive Computing, we present a component
system for developers, a graphical toolkit for customizers, and
self-configuration algorithms to ease the deployment.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-08&engl=0}
}
@inproceedings {INPROC-2005-96,
author = {Abdelmajid Khelil and Jos{\'e} Pedro Marr{\'o}n and Christian Becker and Kurt Rothermel},
title = {{Hypergossiping: A Generalized Broadcast Strategy for Mobile Ad Hoc Networks}},
booktitle = {Proceedings of Kommunikation in Verteilten Systemen 2005 (KiVS'05); Kaiserslautern, Germany, 2005},
address = {Kaiserslautern},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {0--1},
type = {Konferenz-Beitrag},
month = {Februar},
year = {2005},
keywords = {mobile ad hoc network (MANET); adaptive broadcast; network partitioning},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols},
contact = {Universit{\"a}t Stuttgart / IPVS / VS Universit{\"a}tsstrasse 38, 70569 Stuttgart, Germany +49 711 7816 {251, 357, 228, 434} {khelil, marron, becker, rothermel}@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Broadcasting is a commonly used communication primitive needed by many
applications and protocols in mobile ad hoc networks (MANETs). Unfortunately,
most broadcast solutions are tailored to one class of MANETs with respect to
node density and node mobility and are unlikely to operate well in other
classes. In this paper, we introduce hypergossiping, a novel adaptive broadcast
algorithm that combines two strategies. Hypergossiping uses adaptive gossiping
to efficiently distribute messages within single network partitions and
implements an efficient heuristic to distribute them across partitions.
Simulation results in ns-2 show that hypergossiping operates well for a broad
range of MANETs with respect to node densities and mobility levels.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-96&engl=0}
}
@inproceedings {INPROC-2005-73,
author = {Marcus Handte and Christian Becker and Kurt Rothermel},
title = {{Peer-based Automatic Configuration of Pervasive Applications}},
booktitle = {Proceedings of the 2nd IEEE International Conference on Pervasive Services (ICPS 2005), Santorini, Greece, 11-14 July,2005},
publisher = {-},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {249--260},
type = {Konferenz-Beitrag},
month = {Juli},
year = {2005},
language = {Deutsch},
cr-category = {D.2.7 Software Engineering Distribution, Maintenance, and Enhancement},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive computing envisions seamless support for user tasks through
cooperating devices that are present in an environment. Fluctuating
availability of devices, induced by mobility and failures, requires mechanisms
and algorithms that allow applications to adapt to changing environmental
conditions without user intervention. To ease the development of adaptive
applications, we have proposed the peer-based component system PCOM. This
system provides fundamental mechanisms to support the automated composition of
applications at runtime. In this paper, we discuss the requirements on
peer-based automatic configuration of pervasive applications and present an
approach based on distributed constraint satisfaction. The resulting algorithm
configures applications in the presence of strictly limited resources. To show
the feasibility of the approach, we have integrated the algorithm into PCOM and
provide an evaluation based on simulation and measurements.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-73&engl=0}
}
@inproceedings {INPROC-2005-72,
author = {Marcus Handte and Gregor Schiele and Stephan Urbanski and Christian Becker},
title = {{Adaptation Support for Stateful Components in PCOM}},
booktitle = {Workshop on Software Architectures for Self-Organization: Beyond Ad-Hoc Networking at Pervasive 2005, M{\"u}nchen, Germany, 2005},
publisher = {-},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--5},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2005},
keywords = {Adaptation, Stateful Services},
language = {Deutsch},
cr-category = {D.2.7 Software Engineering Distribution, Maintenance, and Enhancement},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In ever-changing environments as they are envisioned in Pervasive Computing,
applications have to adapt to changes in their execution environment.
Reselection of services is a common technique for stateless services. This
paper presents an approach that allows reselection of stateful services by
combining checkpointing techniques and client-side request histories. An
implementation that allows transparent service reselection is outlined and
parameters for the automatic creation of checkpoints are discussed.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-72&engl=0}
}
@inproceedings {INPROC-2005-31,
author = {Frank D{\"u}rr and Christian Becker and Kurt Rothermel},
title = {{Efficient Forwarding of Symbolically Addressed Geocast Messages}},
booktitle = {Proceedings of the 14th International Conference on Computer Communications an Networks (ICCCN 2005); San Diego, CA, October 2005},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {77--85},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2005},
doi = {10.1109/ICCCN.2005.1523812},
keywords = {Geocast, Multicast, Networking, Communication Network, Location-based Service},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2005-31/INPROC-2005-31.pdf,
http://dx.doi.org/10.1109/ICCCN.2005.1523812},
contact = {frank.duerr@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Geocast is used to send messages to all hosts located in a geographic area.
This target area can be defined either by geometric figures like polygons or by
symbolic addresses like city names or room numbers.
Geographic routing algorithms, which forward messages based on geographic
information, can be used to forward geocast messages. If routing of
symbolically addressed messages is based on geometric coordinates, complex
mappings between symbolic addresses and their geometric extent as well as
complex geometric operations are required. Therefore, we propose a routing
algorithm for symbolically addressed geocast messages that operates directly on
a symbolic location model. This approach does not require any geometric
information for message forwarding, and forwarding decisions can be realized
efficiently by comparably simple operations.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-31&engl=0}
}
@inproceedings {INPROC-2004-86,
author = {Christian Becker and Marcus Handte and Gregor Schiele and Kurt Rothermel},
title = {{PCOM - A Component System for Pervasive Computing}},
booktitle = {Proceedings of the Second IEEE International Conference on Pervasive Computing and Communications},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {67--77},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2004},
keywords = {pervasive computing; ubiquitous computing; system software; component system; 3PC},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Applications in the Pervasive Computing domain are challenged by the dynamism
in which their execution environment changes, e.g. due to user mobility. As a
result, applications have to adapt to changes regarding their required
resources. In this paper we present PCOM, a component system for Pervasive
Computing. PCOM offers application programmers a high-level programming
abstraction which captures the dependencies between components using contracts.
The resulting application architecture is a tree formed by components and their
dependencies. PCOM supports automatic adaptation in cases where the execution
environment changes to the better or to the worse. User supplied as well as
system provided strategies take users out of the control loop while offering
flexible adaptation control.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-86&engl=0}
}
@inproceedings {INPROC-2004-59,
author = {J{\"o}rg H{\"a}hner and Christian Becker and Pedro Jos{\'e} Marr{\'o}n},
title = {{Consistent Context Management in Mobile Ad Hoc Networks}},
booktitle = {Informatik 2004 - Informatik verbindet. Vol. 1},
editor = {Peter Dadam and Manfred Reichert},
publisher = {Gesellschaft f{\"u}r Informatik},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
series = {Lecture Notes in Informatics},
volume = {51},
pages = {308--313},
type = {Konferenz-Beitrag},
month = {September},
year = {2004},
language = {Englisch},
cr-category = {H.1 Models and Principles},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2004-59/INPROC-2004-59.pdf},
contact = {J{\"o}rg H{\"a}hner joerg.haehner@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {John entered his office. John left his office. The order of these updates to a
context-aware system is important to reflect the state in the real world.
Context information obtained by sensor systems requires consistency concepts
which reflect the chronological ordering in which context information has been
captured. This paper introduces a consistency concept which allows to express
the ordering of events which happened outside of a computer system.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-59&engl=0}
}
@inproceedings {INPROC-2004-54,
author = {Kay R{\"o}mer and Christian Frank and Pedro Marr{\'o}n and Christian Becker},
title = {{Generic Role Assignment for Wireless Sensor Networks}},
booktitle = {Proceedings of the 11th ACM SIGOPS European Workshop},
address = {Leuven, Belgium},
publisher = {self-publisher},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {7--12},
type = {Konferenz-Beitrag},
month = {September},
year = {2004},
keywords = {sensor network; self-configuration; role assignment},
language = {Englisch},
cr-category = {C.2.2 Network Protocols,
C.2.3 Network Operations,
D.3.2 Programming Language Classifications},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2004-54/INPROC-2004-54.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Wireless ad hoc networks of sensor nodes are envisioned to be deployed in the
physical environment to monitor a wide variety of real-world phenomena. Almost
any sensor network application requires some form of selfconfiguration, where
sensor nodes take on specific functions or roles in the network without manual
intervention. These roles may be based on varying sensor node properties (e.g.,
available sensors, location, network neighbors) and may be used to support
applications requiring heterogeneous node functionality (e.g., clustering, data
aggregation). In this paper we argue that the assignment of user-defined roles
is a fundamental part of a wide range of sensor network applications.
Consequently, a framework for assignment of roles to sensor nodes in an
application-specific manner could significantly ease sensor network
programming. We outline the general structure of such a framework and present a
first approach to its realization. We demonstrate its utility and feasibility
using a number of concrete examples.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-54&engl=0}
}
@inproceedings {INPROC-2004-52,
author = {Pedro Marr{\'o}n and Andreas Lachenmann and Daniel Minder and J{\"o}rg H{\"a}hner and Kurt Rothermel and Christian Becker},
title = {{Adaptation and Cross-Layer Issues in Sensor Networks}},
booktitle = {Proceedings of the 2004 Intelligent Sensors, Sensor Networks and Information Processing Conference : ISSNIP '04 ; Melbourne, December 14-17, 2004},
publisher = {self-publisher},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {623--628},
type = {Konferenz-Beitrag},
month = {Dezember},
year = {2004},
isbn = {0-7803-8894-1},
keywords = {sensor network; system architecture; adaptation; framework; code distribution; cross-layer},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols,
D.4.7 Operating Systems Organization and Design},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2004-52/INPROC-2004-52.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {An intrinsic characteristic of current projects in the area of sensor networks
is the heterogeneity of hardware and application requirements. In addition, the
requirements of current applications are expected to change over time. This
makes developing, deploying, and optimizing sensor network applications an
extremely difficult task. In this paper, we present the architecture of
TinyCubus, a flexible and adaptive crosslayer framework for TinyOS-based sensor
networks that aims at providing the necessary infrastructure to cope with the
complexity of such systems. TinyCubus consists of three parts: a data
management framework that selects and adapts both system and data management
components, a cross-layer framework that enables optimizations through
cross-layer interactions, and a configuration engine that installs components
dynamically. We show the feasibility of our architecture by describing and
evaluating a code distribution algorithm that optimizes its behavior by using
application knowledge about the sensor topology.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-52&engl=0}
}
@inproceedings {INPROC-2004-38,
author = {Christian Becker and Daniela Nicklas},
title = {{Where do spatial context-models end and where do ontologies start? A proposal of a combined approach}},
booktitle = {Proceedings of the First International Workshop on Advanced Context Modelling, Reasoning and Management in conjunction with UbiComp 2004},
editor = {Jadwiga Indulska and David De Roure},
address = {Nottingham, England},
publisher = {University of Southhampton},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {48--53},
type = {Konferenz-Beitrag},
month = {September},
year = {2004},
isbn = {854328130},
keywords = {Context-Models, Adaptation, Infrastructures for Context-Aware Computing, Ubiquitous Computing},
language = {Deutsch},
cr-category = {H.2.1 Database Management Logical Design},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2004-38/INPROC-2004-38.pdf},
contact = {christian.becker@informatik.uni-stuttgart.de, daniela.nicklas@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {Context-aware applications adapt their behavior depending on the state of the
physical world along with other information representing context. This requires
context management, i.e., the efficient management of context information and
feasible context representations in order to allow reasoning. This paper
discusses two common approaches, spatial context models and contextual
ontologies, and argues for a combined approach providing the efficiency of
context management through context models combined with the semantic
expressiveness of ontologies.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-38&engl=0}
}
@inproceedings {INPROC-2004-29,
author = {Frank D{\"u}rr and Nicola H{\"o}nle and Daniela Nicklas and Christian Becker and Kurt Rothermel},
title = {{Nexus--A Platform for Context-Aware Applications}},
booktitle = {1. GI/ITG Fachgespr{\"a}ch Ortsbezogene Anwendungen und Dienste.},
editor = {J{\"o}rg Roth},
address = {Hagen},
publisher = {FernUniversit{\"a}t in Hagen},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
series = {Informatik-Berichte der FernUniversit{\"a}t in Hagen},
volume = {317},
pages = {15--18},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2004},
keywords = {Location-based Service; Context-aware System; Platform; Geocast},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
H.2.4 Database Management Systems,
H.2.8 Database Applications,
H.3.4 Information Storage and Retrieval Systems and Software,
C.2.2 Network Protocols},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2004-29/INPROC-2004-29.pdf},
contact = {Senden Sie eine E-Mail an frank.duerr@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {In this paper we present the Nexus Platform for context-aware applications.
This platform allows to share the effort of setting up a global and detailed
context model between different providers by federating their partial models.
Applications can query data directly, use push-based communication through an
event service, or use value-added services like a navigation or map service for
special tasks. Additional context-aware services like hoarding or geocast can
be implemented on basis of the platform. For the latter we present different
approaches for addressing and efficient message forwarding based on the Nexus
Platform.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-29&engl=0}
}
@inproceedings {INPROC-2004-28,
author = {J{\"o}rg H{\"a}hner and Kurt Rothermel and Christian Becker},
title = {{Update-Linearizability: A Consistency Concept for the Chronological Ordering of Events in MANETs}},
booktitle = {Proceedings of the First IEEE International Conference on Mobile Ad Hoc and Sensor Systems},
publisher = {IEEE Press},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--10},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2004},
language = {Englisch},
cr-category = {H.2 Database Management,
C.2 Computer-Communication Networks},
contact = {J{\"o}rg H{\"a}hner haehner@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Mobile ad hoc networks (MANETs) are used in situations where networks need to
be deployed immediately but no network infrastructure is available. If MANET
nodes have sensing capabilities, they can capture and communicate the state of
their surroundings, including environmental conditions or objects in their
proximity. If the sensed state information is propagated to a database to build
a consistent model of the real world, a variety of promising context-aware
applications becomes possible. In this paper, we introduce a novel consistency
concept that preserves the chronological ordering of sensed state transition
events. Based on this concept, we propose a data replication algorithm for
MANETs that guarantees the consistency concept without relying on synchronized
clocks and show its correctness. Our simulation experiments show that
replicated copies are updated regularly even if the network load in the system
is high.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-28&engl=0}
}
@inproceedings {INPROC-2004-27,
author = {Gregor Schiele and Christian Becker and Kurt Rothermel},
title = {{Energy-Efficient Cluster-based Service Discovery}},
booktitle = {Proceedings of the 11th ACM SIGOPS European Workshop (SIGOPSEW04); Leuven, Belgium, September 20-22, 2004},
publisher = {ACM SIGOPS},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {75--79},
type = {Konferenz-Beitrag},
month = {September},
year = {2004},
keywords = {SANDMAN; service discovery; energy-efficient; energy-aware},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
contact = {gregor.schiele@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Service discovery in Ubiquitous Computing is a task which has to be done
frequently due to dynamically changing environments. The limited battery power
of mobile devices requires us to optimize frequent and energy costly tasks,
especially the ones incurring in communication activities. In this paper we
present a novel service discovery algorithm based on node clustering. Nodes
within a cluster may sleep to save energy when idle. A clusterhead node is
always active and answers discovery requests on behalf of other nodes to
achieve low discovery latencies. Simulation experiments show energy savings of
up to 66\% compared to an approach where all nodes are permanently active while
the discovery latencies were not increased.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-27&engl=0}
}
@inproceedings {INPROC-2004-06,
author = {J{\"o}rg H{\"a}hner and Dominique Dudkowski and Pedro Jos{\'e} Marr{\'o}n and Christian Becker},
title = {{Partitioning in Mobile Ad Hoc Networks}},
booktitle = {2. GI/ITG KuVS-Fachgespr{\"a}ch ``Drahtlose Sensornetzwerke''},
address = {Karlsruhe, Germany},
publisher = { },
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {Februar},
year = {2004},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
D.2.8 Software Engineering Metrics},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The performance of distributed algorithms in mobile ad hoc networks is strongly
influenced by the connectivity of the network. In cases where the connectivity
is low, network partitioning occurs. The mobility and density of network nodes,
i.e. the movement of nodes and the number of nodes per unit area, are
fundamental properties that have a large impact on the partitioning behavior,
so that a detailed characterization of this behavior may be applied to improve
the performance of distributed algorithms.
In this paper we introduce a set of metrics that describe characteristics
regarding partitioning in mobile ad hoc networks. We have conducted an
extensive set of simulation studies for a wide range of network scenarios to
show the impact of node mobility and density on the proposed metrics. We
present results for the number of partitions, their size over time, and the
frequency of partition changes. From the perspective of individual nodes, we
introduce metrics that describe the time periods in which pairs of nodes are
located in different partitions, and the number of nodes that are in the
partition of an individual node over time.
The results obtained in this paper will allow distributed data management
algorithm designers to characterize those types of network scenarios where
partitioning must be explicitly considered. Especially algorithms in areas such
as replication, data storage, and query processing, may be inspired by the
results at hand. Finally, the optimization of strategies for replica placement,
update frequency, spatial scoping of data, and even more advanced techniques
for data exchange between nodes in frequently partitioned networks will also
benefit from our results.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-06&engl=0}
}
@inproceedings {INPROC-2004-02,
author = {Othmar Lehmann and Martin Bauer and Christian Becker and Daniela Nicklas},
title = {{From Home to World - Supporting Context-aware Applications through World Models}},
booktitle = {Proceedings of the Second IEEE International Conference on Pervasive Computing and Communications},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {297--306},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2004},
keywords = {context; context-awareness; pervasive computing; ubiquitous computing; world model; Nexus},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
H.2.1 Database Management Logical Design,
H.3.4 Information Storage and Retrieval Systems and Software},
ee = {http://www.percom.org/,
http://www.nexus.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {In the vision of pervasive computing smart everyday objects communicate and
cooperate to provide services and information to users. Interoperability
between devices and applications not only requires common protocols but also
common context management. In this paper we discuss requirements on the context
management based on the Georgia Tech's Aware Home environment and the global
context management perspective of the Nexus project. Our experiences with
integrating the Aware Home Spatial Service into the Nexus platform show how
federation concepts and a common context model can provide applications with
uniform context information in different administrative and application
domains.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2004-02&engl=0}
}
@inproceedings {INPROC-2003-65,
author = {Illya Stepanov and J{\"o}rg H{\"a}hner and Christian Becker and Jing Tian and Kurt Rothermel},
title = {{A Meta-Model and Framework for User Mobility in Mobile Networks}},
booktitle = {Proceedings of the 11th International Conference on Networking 2003 (ICON 2003), Sydney, Australia, September 28 - October 1, 2003},
publisher = {IEEE},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {231--238},
type = {Konferenz-Beitrag},
month = {September},
year = {2003},
isbn = {0-7803-7788-5},
keywords = {simulation; mobility modeling; user movement},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.4 Performance of Systems,
I.6.3 Simulation and Modeling Applications},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-65/INPROC-2003-65.pdf,
http://canu.informatik.uni-stuttgart.de/mobisim},
contact = {illya.stepanov@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Mobility patterns play an important role for performance evaluations of mobile
networks. To simulate user movement, existing simulation tools provide only a
few simple mobility models (e.g., random movement) suitable for particular
scenarios. To evaluate a new scenario, an appropriate model needs to be
created, but this requires extra work that distracts the researcher from
his/her main task. In general, three key elements determine the mobility of
users: the spatial environment, the user trip sequences, and the user movement
dynamics (e.g., speed). In this paper, we introduce a meta-model that
integrates these three elements in an easy-to-use framework, allowing a
flexible modeling of user mobility in custom scenarios. The framework is
available for download as a stand-alone trace generator and may be used
together with any simulation or emulation tool for mobile networks to evaluate
a specific scenario.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-65&engl=0}
}
@inproceedings {INPROC-2003-26,
author = {Marcus Handte and Christian Becker and Gregor Schiele},
title = {{Experiences: Minimalism and Extensibility in BASE}},
booktitle = {Proceedings of the System Support for Ubiquitous Computing Workshop (Ubisys03) at the Fifth Annual Conference on Ubiquitous Computing (Ubicomp03); Seattle, Washington, October 12, 2003},
publisher = {online proceedings},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {1--8},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2003},
keywords = {micro-broker; BASE; PCOM; 3PC; ubiquitous computing; pervasive computing; middleware},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
D.2.11 Software Engineering Software Architectures,
D.2.12 Software Engineering Interoperability,
D.4.4 Operating Systems Communications Management},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-26/INPROC-2003-26.pdf,
http://ciae.cs.uiuc.edu/ubisys/program.html,
http://ciae.cs.uiuc.edu/ubisys/},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {In the vision of Ubiquitous Computing everyday objects become smart.
Technically, this requires some sort of processing and communication
technology. We have designed and implemented a middleware for spontaneous
networking in Ubiquitous Computing environments. The major objectives were
minimalism and extensibility in order to deploy the middleware on a variety of
devices ranging from sensor nodes to classical general purpose computers. In
this paper we will assess the taken approach based on two follow-up projects:
the port of BASE to a small embedded system and the design and implementation
of a component system on top of BASE. While the fundamental concepts and design
principles of BASE have proven to be solid, both projects provided insights
that led to minor conceptual and major technical changes.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-26&engl=0}
}
@inproceedings {INPROC-2003-20,
author = {Kurt Rothermel and Dominique Dudkowski and Frank D{\"u}rr and Martin Bauer and Christian Becker},
title = {{Ubiquitous Computing - More than Computing Anytime Anyplace?}},
booktitle = {Proceedings of the 49. Photogrammetrische Woche},
address = {Stuttgart},
publisher = {ifp},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {September},
year = {2003},
keywords = {Kontext; kontextbezogene Systeme; Ubiquitous Computing; Nexus},
language = {Deutsch},
cr-category = {H.2.8 Database Applications,
H.3.4 Information Storage and Retrieval Systems and Software},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-20/INPROC-2003-20.pdf,
http://www.nexus.uni-stuttgart.de},
contact = {Kurt.Rothermel@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {The rapid development of mobile communication networks and the availability of
miniaturized and inexpensive sensor technology allow for the development of
multifunctional mobile devices that are able to collect and communicate context
information. We also currently see a clear trend towards the integration of
embedded systems including sensors into {\ss}mart`` everyday things, which is also
referred to as Ubiquitous Computing. The deployment of sensor technology allows
for so-called context-aware applications, going far beyond of providing mobile
access to information and computing resources. Context-aware applications
exploit captured sensor information to adapt to the current situation of mobile
users. For instance, the information offered to a user may depend on his
current location, and the way how it is presented to him may depend on the
speed he moves, whether he is on its own or with others, and so on.
In this paper, we characterize context-aware applications and present the
vision of a digital world model as the foundation for this class of
applications. Further, the paper discusses the benefits and reseach challenges
associated with digital world models, which allow applications to take into
account the state of the real world and react to state changes.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-20&engl=0}
}
@inproceedings {INPROC-2003-17,
author = {Kurt Rothermel and Dieter Fritsch and Bernhard Mitschang and Paul J. K{\"u}hn and Martin Bauer and Christian Becker and Christian Hauser and Daniela Nicklas and Steffen Volz},
title = {{SFB 627: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme}},
booktitle = {Proceedings Informatik 2003},
address = {Frankfurt},
publisher = {Gesellschaft f{\"u}r Informatik},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {September},
year = {2003},
keywords = {Umgebungsmodelle; kontext-bezogene Systeme; Nexus; Spatial World Models; context-aware systems},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems,
H.2.4 Database Management Systems,
H.2.8 Database Applications,
H.3.4 Information Storage and Retrieval Systems and Software},
ee = {http://www.nexus.uni-stuttgart.de},
contact = {Kurt.Rothermel@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware;
Universit{\"a}t Stuttgart, Institut f{\"u}r Kommunikationsnetze und Rechnersysteme (IKR);
Universit{\"a}t Stuttgart, Institut f{\"u}r Photogrammetrie (ifp)},
abstract = {Ziel des Sonderforschungsbereichs 627 ``Umgebungsmodelle f{\"u}r mobile
kontextbezogene Systeme'' ist die Erforschung von Methoden und Verfahren f{\"u}r die
Definition, die Verwaltung und die Nutzung von digitalen Umgebungsmodellen.
Existierende Informationsr{\"a}ume werden mit komplexen Modellen der realen Welt
verschr{\"a}nkt und erlauben so neuartige Anwendungen. Insbesondere die Klasse der
ortsbezogenen Anwendungen und aktuelle Forschungsgebiete wie das Ubiquitous
Computing k{\"o}nnen von solchen Umgebungsmodellen profitieren, oder werden durch
sie erst erm{\"o}glicht.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-17&engl=0}
}
@inproceedings {INPROC-2003-13,
author = {Christian Becker and Gregor Schiele and Holger Gubbels and Kurt Rothermel},
title = {{BASE - A Micro-broker-based Middleware For Pervasive Computing}},
booktitle = {Proceedings of the First IEEE International Conference on Pervasive Computing and Communication (PerCom), March 23-26, Fort Worth, USA},
address = {Los Alamitos},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {443--451},
type = {Konferenz-Beitrag},
month = {M{\"a}rz},
year = {2003},
isbn = {0-7695-1895},
keywords = {Middleware, Ubiquitous Computing, Microbroker, Micro-broker, BASE},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-13/INPROC-2003-13.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive computing environments add a multitude of additional devices to our
current computing landscapes. Specialized embedded systems provide sensor
information about the real world or offer a distinct functionality, e.g.
presentation on a “smart wall”. Spontaneous networking leads to constantly
changing availability of services. This requires middleware support to ease
application development. Additionally, we argue that an extensible middleware
platform covering small embedded systems to full-fledged desktop computers is
needed. Such a middleware should provide easy-to-use abstractions to access
remote services and device-specific capabilities. We present a micro-broker-
based approach which meets these requirements by allowing uniform access to
device capabilities and services through proxies and the integration of
different interoperability protocols. A minimum configuration of the middleware
can be executed on embedded systems. Resource-rich execution environments are
supported by the extensibility of the middleware.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-13&engl=0}
}
@inproceedings {INPROC-2003-11,
author = {Christian Becker and Gregor Schiele},
title = {{Middleware and Application Adaptation Requirements and their Support in Pervasive Computing}},
booktitle = {Proceedings of the 23rd International Conference on Distributed Computing Systems Workshops (ICDCS 2003), 3rd International Workshop on Distributed Auto-adaptive and Reconfigurable Systems (DARES), Providence, USA, May 19-22},
address = {Los Alamitos},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {98--103},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2003},
isbn = {0-7695-1921-0},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-11/INPROC-2003-11.pdf},
contact = {Email an christian.becker@informatik.uni-stuttgart.de oder gregor.schiele@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive computing environments are characterized by an additional
heterogeneity compared to existing computing infrastructures. Devices ranging
from small embedded systems to full-fledged computers are connected via
spontaneously formed networks. In this paper we analyze requirements of
applications and system software to cope with the dynamically changing
execution environment. Based on our micro-broker-based middleware BASE a
component framework for pervasive computing supporting application adaptation
is proposed.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-11&engl=0}
}
@inproceedings {INPROC-2003-09,
author = {Martin Bauer and Christian Becker and J{\"o}rg H{\"a}hner and Gregor Schiele},
title = {{ContextCube - Providing Context Information Ubiquitously}},
booktitle = {Proceedings of the 23rd International Conference on Distributed Computing Systems Workshops (ICDCS 2003)},
address = {Los Alamitos},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {308--313},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2003},
isbn = {0-7695-1921-0},
language = {Englisch},
cr-category = {H.3.4 Information Storage and Retrieval Systems and Software},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-09/INPROC-2003-09.pdf,
http://www.nexus.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Sensing the state of the environment is an important source for context-aware
applications. Several approaches exist to provide sensor information to mobile
application nodes. As the extreme cases we have pure infrastructures and pure
ad hoc networks. In order to allow sensor platforms to serve both of these
approaches, we have designed a universal sensor platform and integrated it into
an infrastructure-based approach as well as into ad hoc networks. In this paper
we discuss the requirements on such a platform, the design, and the
experiences.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-09&engl=0}
}
@inproceedings {INPROC-2003-07,
author = {Kurt Rothermel and Martin Bauer and Christian Becker},
title = {{Digitale Weltmodelle - Grundlage kontextbezogener Systeme}},
booktitle = {Total vernetzt - Szenarien einer informatisierten Welt},
editor = {Friedemann Mattern},
address = {Berlin, Heiderlberg, New York},
publisher = {Springer-Verlag},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
series = {Xpert.press},
pages = {123--141},
type = {Konferenz-Beitrag},
month = {Mai},
year = {2003},
isbn = {3-540-0023-8},
keywords = {Kontext; kontextbezogene Systeme; Ubiquitous Computing; Nexus},
language = {Deutsch},
cr-category = {H.3.4 Information Storage and Retrieval Systems and Software},
ee = {http://www.nexus.uni-stuttgart.de},
contact = {E-Mail: Kurt.Rothermel@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Die rasant fortschreitende Entwicklung von Sensorsystemen und drahtloser
Kommunikation f{\"u}hrt zu multifunktionalen mobilen Endger{\"a}ten, die in der Lage
sind, Kontextinformation zu erfassen, zu verarbeiten und zu kommunizieren.
Durch die extreme Miniaturisierung eingebetteter Systeme entstehen au{\ss}erdem
``intelligente'' Alltagsgegenst{\"a}nde, die in Netzwerke eingebunden sind und {\"u}ber
sensorische F{\"a}higkeiten verf{\"u}gen. Vor dem Hintergrund dieser Entwicklungen ist
es absehbar, dass in wenigen Jahren Milliarden von Sensoren existieren werden,
die kontinuierlich den Zustand der Realwelt erfassen und kommunizieren. F{\"u}hrt
man die sensorisch gewonnen Informationen in einem r{\"a}umlichen Modell zusammen,
so entsteht ein digitales Abbild der Realwelt, also ein digitales Weltmodell,
das analog zum heutigen Web einen globalen Informationsraum darstellt. Das
digitale Weltmodell kann Grundlage sein f{\"u}r ein breites Spektrum
kontextbezogener Anwendungen, deren Kontext prinzipiell keinen r{\"a}umlichen
Beschr{\"a}nkungen unterworfen ist.
In diesem Beitrag wird der Begriff der kontextbezogene Anwendungen erl{\"a}utert
und Anwendungen dieser Art am Beispiel existierender Systeme beschrieben und
klassifiziert. Au{\ss}erdem wird die Vision, Kontextinformationen in Form digitaler
Weltmodelle zu verwalten, dargelegt und motiviert. Schlie{\ss}lich werden die sich
aus dieser Vision ergebenden wissenschaftlichen Fragestellungen diskutiert.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-07&engl=0}
}
@inproceedings {INPROC-2003-06,
author = {J{\"o}rg H{\"a}hner and Christian Becker and Kurt Rothermel},
title = {{A Protocol for Data Dissemination in Frequently Partitioned Mobile Ad Hoc Networks}},
booktitle = {Proceedings of the Eighth IEEE Symposium on Computers and Communications (ISCC 2003). Vol. I},
editor = {Ahmed Tantawy and Kemal Inan},
address = {Los Alamitos},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {633--640},
type = {Konferenz-Beitrag},
month = {Juni},
year = {2003},
isbn = {0-7695-1961-X},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2003-06/INPROC-2003-06.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Distribution of data in mobile ad hoc networks is challenged when the mobility
of nodes leads to frequent topology changes. Existing approaches so far address
either the network partitioning problem or are capable of handling large
amounts of data, but not both at the same time. In this paper a novel approach
is presented which is based on a negotiation scheme enhanced by an adaptive
repetition strategy. Different strategies for the selection of repeated data
are presented and evaluated. Simulation results show a reduction of data
transfer volume compared to hyper-flooding by 30 to 40\% even in the presence of
frequent network partitions.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-06&engl=0}
}
@inproceedings {INPROC-2002-23,
author = {Abdelmajid Khelil and Christian Becker and Jing Tian and Kurt Rothermel},
title = {{An Epidemic Model for Information Diffusion in MANETs}},
booktitle = {Proceedings of the 5th International Workshop on Modeling, Analysis and Simulation of Wireless and Mobile Systems (MSWiM'02) at MobiCom 2002},
editor = {Teresa Dahlberg and Michela Meo and Albert Zomaya},
address = {Atlanta, Georgia, USA},
publisher = {ACM PRESS},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
series = {ACM MSWiM Proceedings},
pages = {54--60},
type = {Konferenz-Beitrag},
month = {September},
year = {2002},
isbn = {1-58113-610-2},
keywords = {Algorithms; Performance; Reliability; MANET; analytical modeling; adaptive information diffusion},
language = {Englisch},
cr-category = {C.2.1 Network Architecture and Design,
C.2.2 Network Protocols,
I.6.5 Model Development},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2002-23/INPROC-2002-23.pdf,
http://canu.informatik.uni-stuttgart.de/},
contact = {University of Stuttgart / IPVS Breitwiesenstr. 20-22 70565 Stuttgart, Germany +49 711 7816 {251, 357, 228, 434} {khelil, becker, tian, rothermel}@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {Choosing appropriate information dissemination strategies is crucial in mobile
ad hoc networks (MANET) due to the frequent topology changes. Flooding-based
approaches like diffusion have a strong similarity with epidemic spreading of
diseases. Applying epidemiological models to information diffusion allows the
evaluation of such strategies depending on the MANET characteristics, e.g. the
node density. In order to choose appropriate strategies at run time, the model
should be easily evaluated.
In this paper, an epidemic model is developed for a simple information
diffusion algorithm based on simulation results. We analytically investigate
the impact of node density on information diffusion. The analytical model
allows the evaluation at runtime, even on devices with restricted resources,
and thus enables mobile nodes to dynamically adapt their diffusion strategies
depending on the local node density.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-23&engl=0}
}
@inproceedings {INPROC-2002-22,
author = {Christian Becker and Martin Bauer and J{\"o}rg H{\"a}hner},
title = {{Usenet-on-the-fly - Supporting Locality of Information in Spontaneous Networking Entironments}},
booktitle = {Workshop on Ad Hoc Communications and Collaboration in Ubiquitous Computing Envirnments},
editor = {Ramiro Liscano and Gerd Kortuem},
publisher = {n/a},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
pages = {1--1},
type = {Konferenz-Beitrag},
month = {November},
year = {2002},
language = {Englisch},
cr-category = {H.4.3 Information Systems Applications Communications Applications,
H.5.3 Group and Organization Interfaces},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2002-22/INPROC-2002-22.pdf},
contact = {christian.becker@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {People on the move are typically interested in information with respect to
their proximity. Location-based services in general supply users with
information about their proximity typically relying on an infrastructure
storing the information and tracking the mobile objects, i.e. users. In this
paper we present an approach for spontaneous, i.e. ad hoc, networks inspired by
the Usenet. Information is exchanged using a peer-to-peer synchronization
mechanism. The information is made available through channels grouping related
information. The information propagation is solely based on spontaneously
connected devices not requiring any infrastructure. Our prototype
implementation shows the technical feasibility of our approach, whereas
simulation results show the applicability of information diffusion in outdoor
scenarios with a realistic number of nodes, covering a city center.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-22&engl=0}
}
@inproceedings {INPROC-2002-10,
author = {Jing Tian and J{\"o}rg H{\"a}hner and Christian Becker and Illya Stepanov and Kurt Rothermel},
title = {{Graph-Based Mobility Model for Mobile Ad Hoc Network Simulation}},
booktitle = {Proceedings of the 35th Annual Simulation Symposium: San Diego, California, April 14-18, 2002},
editor = {IEEE Computer Society Press},
address = {Washington, Brussels, Tokyo},
publisher = {IEEE Computer Society Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Germany},
pages = {337--345},
type = {Konferenz-Beitrag},
month = {April},
year = {2002},
isbn = {0-7695-1552-5},
keywords = {Mobility Model; Mobile Ad Hoc Network; Simulation; Spatial Model},
language = {Englisch},
cr-category = {I.6 Simulation and Modeling,
G.3 Probability and Statistics},
contact = {canu@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {Imagine a world where people constantly try to pass through walls and cars
suddenly leave the roads and drive into rivers. Although this is unrealistic,
most simulations for mobile ad hoc networks so far are based on the so called
``random walk'' of mobile objects, which are not constrained by their surrounding
spatial environments. In this paper we propose a novel graph-based mobility
model, which provides a more realistic movement than the random walk model by
reflecting the spatial constraints in the real world. We analyzed three
commonly used ad hoc network routing protocols, DSDV, DSR and AODV with both a
random walk-based and our graph-based mobility model. Our simulation results
show that the spatial constraints have a strong impact on the performance of ad
hoc routing protocols.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-10&engl=0}
}
@inproceedings {INPROC-2001-46,
author = {Christian Becker and Gregor Schiele},
title = {{New mechanisms for routing in ad hoc networks}},
booktitle = {Proceedings of the Fourth CaberNet Plenary Workshop; Pisa, Italy, October 9-11, 2001.},
publisher = {not available},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Germany},
type = {Konferenz-Beitrag},
month = {Oktober},
year = {2001},
keywords = {mobile ad hoc routing; model based routing; user profiles},
language = {Englisch},
cr-category = {C.2.2 Network Protocols},
contact = {gregor.schiele@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {Routing in ad hoc networks is challenged by mobility and dynamics of mobile
devices. Hence, classic routing algorithms hardly cope with partitions and
constant topology changes in such networks. Existing routing algorithms are
based on flooding to explore a location or known node locations. In this paper
we present an approach based on additional information available in such
networks that will help to reduce the network load without relying on known
receiver locations.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2001-46&engl=0}
}
@inproceedings {INPROC-2001-36,
author = {Martin Bauer and Christian Becker and Kurt Rothermel},
title = {{Location Models from the Perspective of Context-Aware Applications and Mobile Ad Hoc Networks}},
booktitle = {Workshop on Location Modeling for Ubiquitous Computing, UbiComp 2001},
address = {Atlanta},
publisher = {-},
institution = {Universit{\"a}t Stuttgart : Sonderforschungsbereich SFB 627 (Nexus: Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme), Germany},
type = {Konferenz-Beitrag},
month = {September},
year = {2001},
keywords = {location, location-aware, location model, modeling language, Nexus, Canu},
language = {Englisch},
cr-category = {H.3.4 Information Storage and Retrieval Systems and Software},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2001-36/INPROC-2001-36.pdf},
contact = {Martin.Bauer@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {Location models are crucial to location-aware applications. In this paper we
present two approaches for modeling location information in an
infrastructure-based and an ad hoc network based application scenario. From
these approaches we deduce requirements for a general location modeling
language for ubiquitous computing.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2001-36&engl=0}
}
@article {ART-2006-20,
author = {Christian Becker and Frank D{\"u}rr and Mirko Knoll and Daniela Nicklas and Torben Weis},
title = {{Entwicklung ortsbezogener Anwendungen}},
journal = {Praxis der Informationsverarbeitung und Kommunikation (PIK)},
editor = {Hans G. Kruse},
publisher = {K. G. Saur Verlag},
volume = {29},
number = {1},
pages = {30--36},
type = {Artikel in Zeitschrift},
month = {Januar},
year = {2006},
doi = {10.1515/PIKO.2006.30},
keywords = {ortsbezogene Dienste; Anwendungsentwicklung},
language = {Deutsch},
cr-category = {D.2.2 Software Engineering Design Tools and Techniques},
contact = {Torben Weis torben.weis@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {Ortsbezogene Anwendungen versorgen Benutzer mit Diensten und Informationen in
Abh{\"a}ngigkeit ihrer aktuellen Position. Beispiele sind im Bereich der
Telematikdienste, Touristenf{\"u}hrer und Informationsdienste zu finden.
Anwendungen k{\"o}nnen sich an den Ort oder ganz allgemein an den Kontext des
Benutzers anpassen, indem sie ortsspezifische Informationen anzeigen oder Daten
der jeweiligen Situation entsprechend pr{\"a}sentieren. Es existieren verschieden
Ans{\"a}tze und Architekturen, um ortsbezogene Anwendungen zu realisieren. In
diesem Beitrag stellen wir unterschiedliche Ans{\"a}tze vor, diskutieren deren Vor-
und Nachteile und leiten daraus ein abstraktes Anwendungsmodell f{\"u}r
ortsbezogene Anwendungen ab. Des Weiteren stellen wir Entwicklungswerkzeuge
vor, die wir auf Basis dieses Anwendungsmodells konzipiert haben. Die
Kombination aus Anwendungsmodell und spezialisierten Werkzeugen wird die
Entwicklung ortsbezogener Anwendungen systematisieren und wesentlich
vereinfachen.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2006-20&engl=0}
}
@article {ART-2006-13,
author = {Kurt Rothermel and Thomas Ertl and Fritsch Dieter and Paul J. K{\"u}hn and Bernhard Mitschang and Engelbert Westk{\"a}mper and Christian Becker and Dominique Dudkowski and Andreas Gutscher and Christian Hauser and Lamine Jendoubi and Daniela Nicklas and Steffen Volz and Matthias Wieland},
title = {{SFB 627 – Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme}},
journal = {Informatik - Forschung und Entwicklung},
publisher = {Springer-Verlag},
volume = {21},
number = {1-2},
pages = {105--113},
type = {Artikel in Zeitschrift},
month = {Juni},
year = {2006},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems,
H.2.4 Database Management Systems,
H.2.8 Database Applications,
H.3 Information Storage and Retrieval},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2006-13/ART-2006-13.pdf},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware;
Universit{\"a}t Stuttgart, Institut f{\"u}r Industrielle Fertigung und Fabrikbetrieb (IFF);
Universit{\"a}t Stuttgart, Institut f{\"u}r Visualisierung und Interaktive Systeme, Visualisierung und Interaktive Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Photogrammetrie (ifp);
Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme;
Universit{\"a}t Stuttgart, Institut f{\"u}r Kommunikationsnetze und Rechnersysteme (IKR)},
abstract = {Computersysteme, wie wir sie heute kennen, passen sich typischerweise nicht an
den Benutzer und dessen Situation an. Erste Beispiele von Systemen, die durch
den Bezug zur Realwelt den Kontext des Benutzers einbeziehen, sind
Navigationssysteme, die unter Ber{\"u}cksichtigung der Position eines Benutzers und
der Verkehrslage Richtungsanweisungen geben k{\"o}nnen. Damit innovative
kontextbezogene Anwendungen m{\"o}glich werden, muss der Kontext, also der Zustand
der Realwelt, durch Sensoren erfasst, in das Computersystem {\"u}bermittelt und
dort in Form dynamischer Umgebungsmodelle den Anwendungen zur Verf{\"u}gung
gestellt werden.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2006-13&engl=0}
}
@article {ART-2005-19,
author = {Christian Becker and Frank D{\"u}rr},
title = {{On Location Models for Ubiquitous Computing}},
journal = {Personal and Ubiquitous Computing},
publisher = {Springer-Verlag},
volume = {9},
number = {1},
pages = {20--31},
type = {Artikel in Zeitschrift},
month = {Januar},
year = {2005},
keywords = {Location Model; Umgebungsmodell, Ubiquitous Computing; Context-aware Computing; Location-based Services},
language = {Englisch},
cr-category = {H.0 Information Systems General},
ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2005-19/ART-2005-19.pdf,
http://www.springerlink.com/content/7qjyl3g9hly15ky2/},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Common queries regarding information processing in ubiquitous computing are
based on the location of physical objects. No matter if the next printer, next
restaurant, or friend is searched for, a notion of distances between objects is
required. A search for all objects in a certain geographic area requires the
possibility to define spatial ranges and spatial inclusion of locations. In
this paper we discuss general properties of symbolic and geometric coordinates.
Based on that, we present an overview of existing location models allowing for
position, range, and nearest neighbor queries. The location models are
classified according to their suitability with respect to the query processing
and the involved modeling effort along with other requirements. Besides an
overview of existing location models and approaches the classification of
location models with respect to application requirements can assist developers
in their design decisions.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2005-19&engl=0}
}
@article {ART-2005-08,
author = {Marcus Handte and Christian Becker and Kurt Rothermel},
title = {{Peer-based Automatic Configuration of Pervasive Applications}},
journal = {Journal of Pervasive Computing and Communications},
publisher = {Troubadour Publishing},
volume = {1},
number = {4},
pages = {251--264},
type = {Artikel in Zeitschrift},
month = {Dezember},
year = {2005},
language = {Englisch},
cr-category = {C.2 Computer-Communication Networks,
D.2 Software Engineering,
D.3 Programming Languages},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Pervasive Computing envisions seamless support for user tasks through
cooperating devices that are present in an environment. Fluctuating
availability of devices, induced by mobility and failures, requires mechanisms
and algorithms that allow applications to adapt to their ever-changing
execution environments without user intervention. To ease the development of
adaptive applications, Becker et al. [3] have proposed the peer-based component
system PCOM. This system provides fundamental mechanisms to support the
automated composition of applications at runtime. In this article, we discuss
the requirements on algorithms that enable automatic configuration of pervasive
applications. Furthermore, we show how finding a configuration can be
interpreted as Distributed Constraint Satisfaction Problem. Based on this, we
present an algorithm that is capable of finding an application configuration in
the presence of strictly limited resources. To show the feasibility of this
algorithm, we present an evaluation based on simulations and real-world
measurements and we compare the results with a simple greedy approximation.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2005-08&engl=0}
}
@article {ART-2003-04,
author = {Kurt Rothermel and Martin Bauer and Christian Becker},
title = {{SFB 627 - ``Nexus'' Umgebungsmodelle f{\"u}r mobile kontextbezogene Systeme}},
journal = {it - Information Technology},
editor = {Paul Molitor and Klaus K{\"u}spert and Kurt Rothermel},
address = {M{\"u}nchen},
publisher = {Oldenbourg Wissenschaftsverlag GmbH},
volume = {45},
number = {5},
pages = {293--300},
type = {Artikel in Zeitschrift},
month = {Oktober},
year = {2003},
keywords = {ubiquitous computing; spatial world models; Umgebungsmodelle; context-awareness; kontext-bezogene Systeme; Nexus},
language = {Deutsch},
cr-category = {C.2.4 Distributed Systems,
H.2.4 Database Management Systems,
H.2.8 Database Applications,
H.3.4 Information Storage and Retrieval Systems and Software},
ee = {http://www.nexus.uni-stuttgart.de},
contact = {kurt.rothermel@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Die Entwicklungen im Bereich der Sensortechnologie erlauben eine zunehmende
Miniaturisierung von Sensorplattformen. Diese k{\"o}nnen in Alltagsgegenst{\"a}nde
integriert werden und Umgebungsinformationen durch drahtlose Kommunikation
bereitstellen. F{\"u}hrt man die erfassten Sensordaten zusammen und ordnet diese
Informationen Orten in r{\"a}umlichen Modellen zu, entstehen Umgebungsmodelle. Die
Erforschung von Methoden und Verfahren f{\"u}r die Erstellung, das Management und
die Nutzung der F{\"o}deration solcher Umgebungsmodelle ist Ziel des
Sonderforschungsbereichs 627 an der Universit{\"a}t Stuttgart.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2003-04&engl=0}
}
@article {ART-2002-04,
author = {Martin Bauer and Christian Becker and Kurt Rothermel},
title = {{Location Models from the Perspective of Context-Aware Applications Mobile Ad Hoc Networks}},
journal = {Personal and Ubiquitous Computing},
address = {London},
publisher = {Springer-Verlag},
volume = {6},
number = {5-6},
pages = {322--328},
type = {Artikel in Zeitschrift},
month = {Dezember},
year = {2002},
issn = {1617-4909},
keywords = {context-awareness; location models; ubiquitous computing; MANET; Nexus},
language = {Englisch},
cr-category = {C.2.4 Distributed Systems,
D.2.12 Software Engineering Interoperability,
H.2.3 Database Management Languages},
ee = {http://link.springer.de/link/service/journals/00779/bibs/2006005/20060322.htm,
http://www.nexus.uni-stuttgart.de},
contact = {Martin Bauer Martin.Bauer@informatik.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte H{\"o}chstleistungsrechner, Verteilte Systeme},
abstract = {Location models are crucial for providing location-dependent data to
context-aware applications. In this paper, we present two approaches for
modeling location information taken from an infrastructure-based and an ad hoc
network-based application scenario. From these approaches we derive
requirements for a general location modeling language for ubiquitous computing.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2002-04&engl=0}
}
@inbook {INBOOK-2007-01,
author = {J{\"o}rg H{\"a}hner and Christian Becker and Pedro Jos{\'e} Marr{\'o}n and Kurt Rothermel},
title = {{Drahtlose Sensornetze - Fenster zur Realwelt}},
series = {Die Informatisierung des Alltags},
address = {Berlin, Heidelberg},
publisher = {Springer-Verlag},
pages = {41--60},
type = {Beitrag in Buch},
month = {Juli},
year = {2007},
isbn = {978-3-540-71454-5},
keywords = {Sensornetze; Datenverwaltung; Konsistenz},
language = {Deutsch},
cr-category = {C.2 Computer-Communication Networks,
H.2 Database Management},
ee = {http://dx.doi.org/10.1007/978-3-540-71455-2_4},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {Sensornetze stellen eine technische L{\"o}sung f{\"u}r die Erfassung und Verarbeitung
von Informationen der physischen Welt dar. Dabei handelt es sich um eine Menge
sogenannter Sensorknoten, die — meist drahtlos — miteinander kommunizieren
k{\"o}nnen. Sensorknoten sind miniaturisierte Computer, die — neben einem
Mikroprozessor und einer Kommunikationsschnittstelle — mit Sensoren
ausgestattet sind. Diese Sensoren erlauben es, physikalische Gr{\"o}{\ss}en in der
Umgebung des Knotens zu messen. Mit Hilfe des Mikroprozessors k{\"o}nnen diese
Messwerte verarbeitet und {\"u}ber die Kommunikationsschnittstelle an andere
Sensorknoten verschickt werden. In diesem Beitrag werden zun{\"a}chst verschiedene
Einsatz-gebiete von Sensornetzen vorgestellt. Danach werden technische
Eigenschaften von Sensornetzen anhand exemplarischer Sensorknoten diskutiert.
Neue wissen-schaftliche Herausforderungen werden beispielhaft anhand des
Gebiets der Daten-verwaltung in Sensornetzen vorgestellt.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2007-01&engl=0}
}
@inbook {INBOOK-2004-09,
author = {Uwe Kubach and Christian Becker and Illya Stepanov and Jing Tian},
title = {{Simulation Model and Tool for Mobile Location Dependent Information Access}},
series = {Mobile Computing Handbook},
address = {New York},
publisher = {CRC Press},
type = {Beitrag in Buch},
month = {Juni},
year = {2004},
isbn = {0849319714},
language = {Englisch},
cr-category = {C.2.0 Computer-Communication Networks, General,
C.2.1 Network Architecture and Design,
C.2.4 Distributed Systems,
C.4 Performance of Systems,
I.6.3 Simulation and Modeling Applications,
H.2 Database Management},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Verteilte Systeme},
abstract = {},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2004-09&engl=0}
}
@proceedings {PROC-2007-01,
editor = {Christian Becker and Christian S. Jensen and Daniela Nicklas and Jianwen Su},
title = {{Proceedings of the 8th International Conference on Mobile Data Management (MDM'07) : Mannheim, Germany, May 7-11, 2007}},
publisher = {IEEE Computer Society},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
pages = {232},
type = {Tagungsband},
month = {Mai},
year = {2007},
isbn = {1-4244-1240-4},
keywords = {mobile data management},
language = {Deutsch},
cr-category = {E.2 Data Storage Representations,
H.2 Database Management},
ee = {http://mdm2007.uni-mannheim.de/},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware},
abstract = {Message from the General Chairs The last two decades have seen a radical change
in the way computers and computing are embedded in society. Historically, the
Personal Computer and the Internet were the milestones that changed both the
computer industry and the way society perceived computers. Today, mobility and
the pervasive use of computing devices have resulted in a fundamental change in
paradigm. Data is no longer static, residing on a disk and on a personal
computer. Now data is something available everywhere, through a multitude of
commodity devices and constantly broadcast through a variety of channels. The
impact on industry and on the way we work with data has become obvious. For
instance, portable digital music players are forcing the music industry to
change its business model, soon the same will happen with video and television.
Similarly, some major telecommunication companies have recently embarked in an
effort to replace the old phone network with an IP based solution for all forms
of communication, thereby blurring even further the boundaries between
communication and computation. The International Conference on Mobile Data
Management lies at the heart of all these changes. In the same way that the
Personal Computer and the first spreadsheet revolutionized the industry, the
new world of pervasive and ubiquitous access to information requires new
approaches to the way we deal with data. And these new approaches need
appropriate venues to be presented and discussed. Taking place in Mannheim,
Germany, MDM 2007 aims at serving as both as a top research conference as well
as a catalyst for new ideas and increased interactions between research and
industry. With an excellent technical program encompassing research papers and
demonstrators, and the complement of several seminars and workshops dedicated,
MDM 2007 has become the leading research venue for innovative research in all
aspects data management related to mobile, wearable, and pervasive computing.
The success of MDM 2007 is nevertheless not due solely to the importance of the
area. Organizing a conference requires the concerted effort of many individuals
during a prolonged period of time, often extending well beyond the conference
itself. As the Conference Chairs, we would like express our thanks and
gratitude to all those who have helped to make MDM 2007 possible. First and
foremost to the PC Chairs: Christian Becker, Christian Jensen, and Jianwen Su,
who have put together an excellent technical program. The program has been
complemented by an exciting demo track thanks to the efforts of Dieter Pfoser.
Panels, seminars, and workshops round up the program and have helped to make
the conference more attractive. The have been coordinated by Agnes Voisard,
Ralf Hartmut G{\"u}ting, and Birgitta K{\"o}nig-Ries, respectively. Special thanks go
to Daniela Nicklas for her efforts with the proceedings and to Torben Weis for
taking care of financial and budget matters. Klemens B{\"o}hm and Arno Jacobsen
were in charge of publicity and advertising the conference. Last but not least,
we want to thank the local organizers, who have done a great job in taking care
of all the menial but often cumbersome aspects of running a conference:
Christian Becker, Wolfgang Effelsberg, Armin Heinzl, and Martin Schader.
Looking forward to seeing you in Mannheim!
Gustavo Alonso and Pedro Jose Marron General Chairs},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=PROC-2007-01&engl=0}
}