Search For:

Displaying 1-50 out of 84 total
FRESCO: A Framework to Estimate the Energy Consumption of Computers
Found in: 2014 IEEE 16th Conference on Business Informatics (CBI)
By Pavel Efros,Erik Buchmann,Klemens Bohm
Issue Date:July 2014
pp. 199-206
Many application areas, e.g., demand response, energy accounting or energy-aware scheduling, require estimates of the energy consumption of computer systems. However, existing estimation approaches often make restrictive assumptions regarding the effort at...
Conceptual Modeling for Mobile Maintenance: The ComVantage Case
Found in: 2014 47th Hawaii International Conference on System Sciences (HICSS)
By Robert Andrei Buchmann
Issue Date:January 2014
pp. 3390-3399
The paper presents a fragment of a hybrid modeling method designed for the maintenance sub domain of the ComVantage EU research project. The method as a whole addresses modeling needs for business stakeholders trying to achieve business-IT alignment with t...
A site properties assessment framework for wireless sensor networks
Found in: Proceedings of the 11th ACM Conference on Embedded Networked Sensor Systems (SenSys '13)
By A. Buchmann, I. Gurov, K. Van Laerhoven, P. E. Guerrero, M. Brachmann, S. Santini
Issue Date:November 2013
pp. 1-2
Comparing experimental results obtained on different wireless sensor network deployments is typically very cumbersome and in most cases unfeasible. This is due to the lack of a methodology to describe the properties of network deployments and the experimen...
Read optimisations for append storage on flash
Found in: Proceedings of the 17th International Database Engineering & Applications Symposium (IDEAS '13)
By Alejandro Buchmann, Robert Gottstein, Ilia Petrov
Issue Date:October 2013
pp. 106-113
Append-/Log-based Storage Managers (LbSM) for database systems represent a good match for the characteristics and behaviour of Flash technology. LbSM alleviate random writes reducing the impact of Flash read/write asymmetry, increasing endurance and perfor...
Distributed optimization of event dissemination exploiting interest clustering
Found in: 2013 IEEE 38th Conference on Local Computer Networks (LCN 2013)
By Max Lehn,Robert Rehner,Alejandro Buchmann
Issue Date:October 2013
pp. 328-331
In distributed real-time applications, such as online games or interactive conferencing systems, timeliness of update event dissemination is a prevailing requirement. Direct connections are often the best solution. However, participants' connection bandwid...
Assessing trust in the long-term protection of documents
Found in: 2013 IEEE Symposium on Computers and Communications (ISCC)
By Martin Vigil,Daniel Cabarcas,Johannes Buchmann,Jingwei Huang
Issue Date:July 2013
pp. 000185-000191
Digital archives rely on trusted parties, such as certification authorities, to ensure authenticity, integrity and proof of existence protection for documents. In this paper, we analyse the trust assumptions that a verifier has to make in order to trust in...
The Costs of Privacy in Local Energy Markets
Found in: 2013 IEEE 15th Conference on Business Informatics (CBI)
By Erik Buchmann,Stephan Kessler,Patrick Jochem,Klemens Bohm
Issue Date:July 2013
pp. 198-207
Many renewable sources for electricity generation are distributed and volatile by nature, and become inefficient and difficult to coordinate with traditional power transmission paths. As a part of the transition from fossil fuel to renewable sources, local...
Privacy through Uncertainty in Location-Based Services
Found in: 2013 14th IEEE International Conference on Mobile Data Management (MDM)
By Shawn Merrill,Nilgun Basalp,Joachim Biskup,Erik Buchmann,Chris Clifton,Bart Kuijpers,Walied Othman,Erkay Savas
Issue Date:June 2013
pp. 67-72
Location-Based Services (LBS) are becoming more prevalent. While there are many benefits, there are also real privacy risks. People are unwilling to give up the benefits - but can we reduce privacy risks without giving up on LBS entirely? This paper explor...
On the Security of Encrypted Secret Sharing
Found in: 2013 46th Hawaii International Conference on System Sciences (HICSS)
By Johannes Braun,Alexander Wiesmaier,Johannes Buchmann
Issue Date:January 2013
pp. 4966-4975
Sensitive electronic data must often be kept confidential over very long periods of time. Known solutions such as conventional encryption, cascaded encryption, and information theoretic schemes suffer from several weaknesses or serious disadvantages that w...
Eventlets: Components for the integration of event streams with SOA
Found in: 2012 5th IEEE International Conference on Service-Oriented Computing and Applications (SOCA)
By Stefan Appel,Sebastian Frischbier,Tobias Freudenreich,Alejandro Buchmann
Issue Date:December 2012
pp. 1-9
Cyber physical systems (CPS) react to changes in the environment and have become widely adopted in many domains. One key functionality to achieve this reactivity is the processing of event streams. To profit from this reactive behavior in service-oriented ...
All-Weather Transport Essentials
Found in: IEEE Internet Computing
By C. Leng,W. W. Terpstra,M. Lehn,R. Rehner,A. Buchmann
Issue Date:November 2012
pp. 30-39
Since the original design of TCP and UDP, the world has changed, and with it, the Internet. Here, the authors argue that transport protocol architectures, most notably TCP's, must be updated to meet the needs of today's Internet. Their optimistic approach ...
Ensuring well-formedness of configured domain models in model-driven product lines based on negative variability
Found in: Proceedings of the 4th International Workshop on Feature-Oriented Software Development (FOSD '12)
By Felix Schwägerl, Thomas Buchmann
Issue Date:September 2012
pp. 37-44
Model-driven development is a well-known practice in modern software engineering. Many tools exist which allow developers to build software in a model-based or even model-driven way, but they do not provide dedicated support for software product line devel...
ACTrESS: automatic context transformation in event-based software systems
Found in: Proceedings of the 6th ACM International Conference on Distributed Event-Based Systems (DEBS '12)
By Alejandro P. Buchmann, Sebastian Frischbier, Stefan Appel, Tobias Freudenreich
Issue Date:July 2012
pp. 179-190
Event-based systems (EBS) enable companies to respond to changes in their environment in a timely manner. To interpret event notifications, knowledge about their context is essential. The matching mechanisms of publish/subscribe systems depend on a common ...
Wireless sensor networks in the wild: three practical issues after a middleware deployment
Found in: Proceedings of the 6th International Workshop on Middleware Tools, Services and Run-time Support for Networked Embedded Systems (MidSens '11)
By Alejandro Buchmann, Christian Seeger, Kristof Van Laerhoven
Issue Date:December 2011
pp. 1-6
This paper reflects on experiences in deploying middleware for a body sensor network, using commercial biosensors. Three types of issues are highlighted that arose during the deployment, which impact middleware design in particular: 1) How can the architec...
Integration of Association Rule Detection with Rule-Based Ontological Support for Product Recommendation
Found in: Symbolic and Numeric Algorithms for Scientific Computing, International Symposium on
By Anita Hejja,Robert Andrei Buchmann,Anamaria Szekely
Issue Date:September 2011
pp. 137-144
Recommender systems can increase the sales by suggesting to users additional products, that were selected by their preferences. Availability of efficient mechanisms for generating the adequate products and for capturing the eligible information are the mos...
Mapping a Relational Database into a RDF Repository
Found in: Symbolic and Numeric Algorithms for Scientific Computing, International Symposium on
By Anamaria Szekely,Anita Hejja,Robert Andrei Buchmann
Issue Date:September 2011
pp. 175-182
Lately, we hear more and more about Semantic Web and the benefits that it brings to the current Web. But just a few companies are adopting solutions based on semantic web technologies, one reason being that their currently information technology systems ar...
An online gaming testbed for peer-to-peer architectures
Found in: Proceedings of the ACM SIGCOMM 2011 conference on SIGCOMM (SIGCOMM '11)
By Alejandro Buchmann, Christof Leng, Max Lehn, Robert Rehner, Tonio Triebel
Issue Date:August 2011
pp. 474-475
In this demo we present a testbed environment for Peer-to-Peer (P2P) game architectures. It is based on Planet PI4, an online multiplayer game whose gameplay provides a standard workload for a set of gaming-specific network interfaces. Its pluggable archit...
Designing a testbed for large-scale distributed systems
Found in: Proceedings of the ACM SIGCOMM 2011 conference on SIGCOMM (SIGCOMM '11)
By Alejandro Buchmann, Christof Leng, Max Lehn, Robert Rehner
Issue Date:August 2011
pp. 400-401
Different evaluation methods for distributed systems like prototyping, simulation and emulation have different tradeoffs. We present a testbed for Internet applications that supports real-network prototypes and multiple simulators with unchanged applicatio...
On the Performance of Database Query Processing Algorithms on Flash Solid State Disks
Found in: Database and Expert Systems Applications, International Workshop on
By Daniel Bausch,Ilia Petrov,Alejandro Buchmann
Issue Date:September 2011
pp. 139-144
Flash Solid State Disks induce a drastic change in storage technology that impacts database systems. Flash memories exhibit low latency (especially for small block sizes), very high random read and low random write throughput, and significant asymmetry bet...
An efficient mobile PACE implementation
Found in: Proceedings of the 6th ACM Symposium on Information, Computer and Communications Security (ASIACCS '11)
By Alex Wiesmaier, Detlef Hhnlein, Falko Strenzke, Franziskus Kiefer, Johannes Braun, Johannes Buchmann, Moritz Horsch
Issue Date:March 2011
pp. 176-185
Many future electronic identity cards will be equipped with a contact-less interface. Analysts expect that a significant proportion of future mobile phones support Near Field Communication (NFC) technology. Thus, it is a reasonable approach to use the cell...
Towards an Estimation Model for Software Maintenance Costs
Found in: Software Maintenance and Reengineering, European Conference on
By Irene Buchmann, Sebastian Frischbier, Dieter Pütz
Issue Date:March 2011
pp. 313-316
Today there is no best practise method available to effectively estimate the maintenance costs of historically grown large-scale software landscapes. Most cost estimation models are either not generalizable due to highly specialized scenarios or too abstra...
Towards a Common Interface for Overlay Network Simulators
Found in: Parallel and Distributed Systems, International Conference on
By Christian Groß, Max Lehn, Dominik Stingl, Aleksandra Kovacevic, Alejandro Buchmann, Ralf Steinmetz
Issue Date:December 2010
pp. 59-66
Simulation has become an important evaluation method in the area of Peer-to-Peer (P2P) research due to the scalability limitations of evaluation test beds such as Planet Lab or G-Lab. Current simulators provide various abstraction levels for different unde...
Energy-efficient processing of spatio-temporal queries in wireless sensor networks
Found in: Proceedings of the 18th SIGSPATIAL International Conference on Advances in Geographic Information Systems (GIS '10)
By Erik Buchmann, Klemens Bohm, Markus Bestehorn, Stephan Kessler
Issue Date:November 2010
pp. 340-349
Research on Moving Object Databases (MOD) has resulted in sophisticated query mechanisms for moving objects and regions. Wireless Sensor Networks (WSN) support a wide range of applications that track or monitor moving objects. However, applying the concept...
Tackling Compliance Deficits of Data-Protection Law with User Collaboration - A Feasibility Demonstration with Human Participants
Found in: E-Commerce Technology, IEEE International Conference on
By Thorben Burghardt, Erik Buchmann, Klemens Böhm, Jürgen Kühling, Simon Bohnen, Anastasios Sivridis
Issue Date:November 2010
pp. 120-127
In the recent past, there have been frequent reports on privacy violations by service providers on the Web. The providers are overstrained with the legal implications of processing personal data. Data-protection authorities in turn are overburdened with th...
An Eye Tracking Semantic Repository for User Profiling
Found in: Symbolic and Numeric Algorithms for Scientific Computing, International Symposium on
By Robert Andrei Buchmann, Radu Meza, Anita Hejja
Issue Date:September 2010
pp. 215-222
The paper details the modeling and processing of a semantic behavior repository for Web users/customers in the context of an application model that involves the capturing of eye tracking during the user-interface interaction, AJAX-style communication betwe...
Towards benchmarking of AMQP
Found in: Proceedings of the Fourth ACM International Conference on Distributed Event-Based Systems (DEBS '10)
By Alejandro Buchmann, Kai Sachs, Stefan Appel
Issue Date:July 2010
pp. 99-100
With the increasing importance of event-based systems the performance of underlying event transporting systems, such as message oriented middleware (MOM), becomes business critical. Therefore, we see a strong need for benchmarks for such environments. Seve...
Real-time social networking profile information semantization using pipes and FCA
Found in: International Conference on Automation, Quality and Testing, Robotics
By R. Meza, R. A. Buchmann
Issue Date:May 2010
pp. 1-5
This paper describes a convenient method of processing and contextualizing information extracted from social networking systems such as Myspace, Facebook or Hi5 users in real-time by using the Yahoo! Pipes feed mash-up service and formal concept analysis. ...
Collaborative data privacy for the web
Found in: Proceedings of the 2010 EDBT/ICDT Workshops (EDBT '10)
By Clemens Heidinger, Erik Buchmann, Klemens Bohm
Issue Date:March 2010
pp. 1-10
While data privacy is a human right, it is challenging to enforce it. For example, if multiple retailers execute a single order at Amazon Marketplace, each retailer can use different agencies for shipment, payment etc., resulting in unmanageable flows of p...
Finding misplaced items in retail by clustering RFID data
Found in: Proceedings of the 13th International Conference on Extending Database Technology (EDBT '10)
By Erik Buchmann, Klemens Bohm, Leonardo Weiss Ferreira Chaves
Issue Date:March 2010
pp. 501-512
In retail, products are organized according to layout plans, so-called planograms. Compliance to planograms is important, since good product placement can significantly increase sales. Currently, retailers are about to implement RFID installations consisti...
A Taxonomy Refining the Security Requirements for Electronic Voting: Analyzing Helios as a Proof of Concept
Found in: Availability, Reliability and Security, International Conference on
By Lucie Langer, Axel Schmidt, Johannes Buchmann, Melanie Volkamer
Issue Date:February 2010
pp. 475-480
Over the past years an approved set of security requirements for electronic voting has been established. However, there is no consistent perception of the exact content and scope of these requirements. Therefore, the corner stone for a comprehensive taxono...
Towards long-term free and secret electronic elections providing voter-verifiability in the bulletin board model
Found in: Proceedings of the 3rd International Conference on Theory and Practice of Electronic Governance (ICEGOV '09)
By Axel Schmidt, Johannes Buchmann, Lucie Langer, Melanie Volkamer, Stefan G. Weber
Issue Date:November 2009
pp. 203-210
From a legal point of view, freedom and secrecy of the vote are as important as transparency and verifiability of the election. However, it is a challenge to reconcile the corresponding requirements for electronic voting schemes. This paper analyzes the li...
Whac-A-Bee: a sensor network game
Found in: Proceedings of the 7th ACM Conference on Embedded Networked Sensor Systems (SenSys '09)
By Alejandro Buchmann, Arthur Herzog, Bernt Schiele, Daniel Jacobi, Eugen Berlin, Kristof Van Laerhoven, Pablo Guerrero
Issue Date:November 2009
pp. 333-334
This paper illustrates both challenges and benefits found in expanding a traditional game concept to a situated environment with a distributed set of wireless sensing modules. Our pervasive game equivalent of the Whac-A-Mole game, Whac-A-Bee, retains the f...
Benchmarking of message-oriented middleware
Found in: Proceedings of the Third ACM International Conference on Distributed Event-Based Systems (DEBS '09)
By Alejandro Buchmann, Kai Sachs, Samuel Kounev, Stefan Appel
Issue Date:July 2009
pp. 1-2
Message-oriented middleware (MOM) is increasingly used as enabling technology for modern event-driven applications typically based on publish/subscribe (pub/sub) communication [1]. Many of these applications are designed for maximum scalability and flexibi...
Event-based applications and enabling technologies
Found in: Proceedings of the Third ACM International Conference on Distributed Event-Based Systems (DEBS '09)
By Alejandro Buchmann, Annika Hinze, Kai Sachs
Issue Date:July 2009
pp. 1-15
Event processing has become the paradigm of choice in many monitoring and reactive applications. However, the understanding of events, their composition and level of abstraction, the style of processing and the quality of service requirements vary drastica...
Towards materialized view selection for distributed databases
Found in: Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology (EDBT '09)
By Erik Buchmann, Fabian Hueske, Klemens Bohm, Leonardo Weiss F. Chaves
Issue Date:March 2009
pp. 94-104
Materialized views (MV) can significantly improve the query performance of relational databases. In this paper, we consider MVs to optimize complex scenarios where many heterogeneous nodes with different resource constraints (e.g., CPU, IO and network band...
Towards Efficient Processing of General-Purpose Joins in Sensor Networks
Found in: Data Engineering, International Conference on
By Mirco Stern, Erik Buchmann, Klemens Böhm
Issue Date:April 2009
pp. 126-137
Join processing in wireless sensor networks is difficult: As the tuples can be arbitrarily distributed within the network, matching pairs of tuples is communication intensive and costly in terms of energy. Current solutions only work well with specific pla...
Maintaining replicas in unstructured P2P systems
Found in: Proceedings of the 2008 ACM CoNEXT Conference (CONEXT '08)
By Alejandro P. Buchmann, Bettina Kemme, Christof Leng, Wesley W. Terpstra, Wilhelm Stannat
Issue Date:December 2008
pp. 1-12
Replication is widely used in unstructured peer-to-peer systems to improve search or achieve availability. We identify and solve a subclass of replication problems where each object is associated with a maintainer node, and its replicas should only be avai...
Discovering the Scope of Privacy Needs in Collaborative Search
Found in: Web Intelligence and Intelligent Agent Technology, IEEE/WIC/ACM International Conference on
By Thorben Burghardt, Erik Buchmann, Klemens Böhm
Issue Date:December 2008
pp. 910-913
Collaborative search engines (CSE) are an upcoming trend in WWW search. CSE let knowledge workers concert their efforts and support user collaboration. However, search terms and links clicked that are shared among users reveal their interests, habits, soci...
PRIMO - Towards Privacy Aware Image Sharing
Found in: Web Intelligence and Intelligent Agent Technology, IEEE/WIC/ACM International Conference on
By Thorben Burghardt, Andreas Walter, Erik Buchmann, Klemens Böhm
Issue Date:December 2008
pp. 21-24
A growing number of users in Web 2.0 based social network sites and photo sharing portals upload millions of images per day. In many cases, this leads to serious privacy threats. The images reveal not only the personal relationships and attitudes of the up...
Area-based gossip multicast
Found in: Proceedings of the 7th ACM SIGCOMM Workshop on Network and System Support for Games (NetGames '08)
By Alejandro Buchmann, Bettina Kemme, Christian Seeger, Patric Kabus
Issue Date:October 2008
pp. 1-6
This paper presents areacast, a dynamic, area-based gossip multicast that enables a node to multicast messages only to nodes with a shared interest. This multicast can be used in multiplayer games where players want to send position updates, that is inform...
Surviving the Data Glut: The Management of Events Streams in Cyberphysical Systems
Found in: Mexican International Conference on Computer Science
By Alejandro Buchmann
Issue Date:October 2008
pp. 4
No summary available.
A3ME - An Agent-Based Middleware Approach for Mixed Mode Environments
Found in: Mobile Ubiquitous Computing, Systems, Services and Technologies, International Conference on
By Arthur Herzog, Daniel Jacobi, Alejandro Buchmann
Issue Date:October 2008
pp. 191-196
In this paper we introduce a new agent-based approach for middleware in mixed mode environments. Mixed mode environments have different dimensions of heterogeneity: devices with widely differing capabilities, different software, and different communication...
pSense - Maintaining a Dynamic Localized Peer-to-Peer Structure for Position Based Multicast in Games
Found in: Peer-to-Peer Computing, IEEE International Conference on
By Arne Schmieg, Michael Stieler, Sebastian Jeckel, Patric Kabus, Bettina Kemme, Alejandro Buchmann
Issue Date:September 2008
pp. 247-256
This paper presents an algorithm for creating and maintaining a dynamic localized peer-to-peer overlay network with its main application to massively multiplayer games. In these games, players reside in a large game world with many thousands of players but...
Tagmark: reliable estimations of RFID tags for business processes
Found in: Proceeding of the 14th ACM SIGKDD international conference on Knowledge discovery and data mining (KDD '08)
By Erik Buchmann, Klemens Bohm, Leonardo Weiss Ferreira Chaves
Issue Date:August 2008
pp. 5-6
Radio Frequency Identification (RFID) promises optimization of commodity flows in all industry segments. But due to physical constraints, RFID technology cannot detect all RFID tags from an assembly of items. This poses problems when integrating RFID data ...
Directional interfaces for wearable augmented reality
Found in: Proceedings of the 9th ACM SIGCHI New Zealand Chapter's International Conference on Human-Computer Interaction: Design Centered HCI (CHINZ '08)
By Andy Cockburn, Mark Billinghurst, Volkert Buchmann
Issue Date:July 2008
pp. 47-54
Wearable Augmented Reality can be used to overlay information onto the real world. Directional interfaces in wearable Augmented Reality aid users to orient themselves so that previously invisible targets are now inside their field of view. This is relevant...
A Methodology for Performance Modeling of Distributed Event-Based Systems
Found in: 11th IEEE International Symposium on Object/Component/Service-Oriented Real-Time Distributed Computing (ISORC '08)
By S. Kounev,J. Bacon,K. Sachs,A. Buchmann
Issue Date:May 2008
pp. 13-22
Distributed event-based systems (DEBS) are gaining increasing attention in new application areas such as transport information monitoring, event-driven supply-chain management and ubiquitous sensor-rich environments. However, as DEBS increasingly enter the...
ICDE 2008 General Chairs Message
Found in: 2008 IEEE 24th International Conference on Data Engineering (ICDE '08)
By Malu Castellanos,Alejandro Buchmann,Krithi Ramamritham
Issue Date:April 2008
pp. nil135
No summary available.
Design of a cheat-resistant P2P online gaming system
Found in: Proceedings of the 2nd international conference on Digital interactive media in entertainment and arts (DIMEA '07)
By Alejandro P. Buchmann
Issue Date:September 2007
pp. 113-120
Since the huge success of online games and especially that of so called Massively Multiplayer Online Games (MMOGs), the prevention of cheating has been a primary concern of game providers. This is also the main reason why Peer-to-Peer (P2P) architectures a...
Workflow support for wireless sensor and actor networks: a position paper
Found in: Proceedings of the 4th workshop on Data management for sensor networks: in conjunction with 33rd International Conference on Very Large Data Bases (DMSN '07)
By Alejandro Buchmann, Daniel Jacobi, Pablo Ezequiel Guerrero
Issue Date:September 2007
pp. 31-36
As initial challenges of wireless sensor and actor networks (WSANs) are overcome, their application possibilities evolve. For these applications to move mainstream, efficient programming methods are required which can be used by domain experts. So far, the...
Bubblestorm: resilient, probabilistic, and exhaustive peer-to-peer search
Found in: Proceedings of the 2007 conference on Applications, technologies, architectures, and protocols for computer communications (SIGCOMM '07)
By Alejandro P. Buchmann, Christof Leng, Jussi Kangasharju, Wesley W. Terpstra
Issue Date:August 2007
pp. 652-652
Peer-to-peer systems promise inexpensive scalability, adaptability, and robustness. Thus, they are an attractive platform for file sharing, distributed wikis, and search engines. These applications often store weakly structured data, requiring sophisticate...
 1  2 Next >>