@inproceedings {Gjorven.2006.1,
	title = {A Mirror Based Approach to Building Reflective, Adaptive Middleware},
	journal = {3. MiNEMA Workshop, Feb 7-8, Leuven, Belgium},
	year = {2006},
	month = {February},
	publisher = {MiNEMA Research Network},
	type = {1},
	author = {Gj{\o}rven, Eli and Eliassen, Frank and Lund, Ketil and Jan {\O}yvind {Aagedal} and Staehli, Richard}
}
@inproceedings {Gjorven.2006.2,
	title = {Self-Adaptive Systems: a Middleware Managed Approach},
	journal = {2nd IEEE International Workshop on Self-Managed Networks, Systems \& Services (SelfMan 2006)},
	year = {2006},
	month = {June},
	publisher = {Springer},
	type = {Workshop},
	abstract = {Recent works on self-adaptivity use a middleware-based approach where the adaptation mechanisms and meta-level information are separated and externalized from the application code. Current solutions generally target individual life-cycle phases of an application in isolation, preventing easy integration of design-time and run-time adaptability. Integration is needed in order to support the introduction of new adaptive behavior during run-time. Self-adapting systems therefore need to support both planning, instantiation and maintenance of applications throughout their life-time. In this paper we propose middleware managed adaptation, in which services are specified by their behavior, and planned, instantiated and maintained by middleware services in such a way that the behavioral requirements are satisfied throughout the service life-time. Central to this approach is mirror-based reflection, which supports introspection and intercession on an application, or any service, through all the phases of its life-cycle, including pre-runtime. The mirror of a service may contain information about its implementation, including the developer{\textquoteright}s knowledge about how this implementation will perform in different contexts. By making this knowledge available to the middleware, we facilitate the implementation of a wide range of self-adaptive behaviors.},
	isbn = {978-3-540-34739-2},
	author = {Gj{\o}rven, Eli and Eliassen, Frank and Lund, Ketil and Viktor S. Wold {Eide} and Staehli, Richard},
	editor = {Jean-Philippe Martin-Fla {Keller}}
}
@inproceedings {Amundsen.2006.2,
	title = {Service Plans for Context- and QoS-Aware Dynamic Middleware},
	journal = {The Second International Workshop on Services and Infrastructure for the Ubiquitous and Mobile Internet (SIUMI{\textquoteright}06)},
	year = {2006},
	month = {July},
	pages = {70-75},
	publisher = {IEEE},
	type = {Workshop},
	abstract = {State-of-the-art context- and QoS-aware dynamic middleware platforms use information about the environment, in order to evaluate alternative configurations of an application and select the one that best meets the user{\textquoteright}s QoS requirements. The specification of the alternatives is prepared at designtime and associated with the software during deployment. From the information and requirements in the specification, the middleware can synthesis, filter, and compare the alternative application configurations. This paper presents a platform independent specification, referred to as service plan, which contains information elements for specifying configurations, dependencies on the environment, and QoS characteristics. The service plan is specified at a conceptual level to ensure that it can be implemented in a wide range of middleware platforms. The paper describes how the concept is used during deployment, instantiation, and reconfiguration. From the implementation and validation the expressiveness and usefulness of the service plan concept is assessed.},
	isbn = {0-7695-2541-5},
	author = {Sten Lundesgaar {Amundsen} and Lund, Ketil and Eliassen, Frank},
	editor = {Philip S. Yu Anto {Corradi}}
}
@article {Floch.2006.1,
	title = {Using Architecture Models for Runtime Adaptability},
	journal = {IEEE Software},
	volume = {23},
	number = {2},
	year = {2006},
	month = {March/April},
	pages = {62-70},
	abstract = {Developers typically use software architecture models at design time to capture significant decisions about a software system{\textquoteright}s organization and to describe and establish a common understanding about the system{\textquoteright}s abstract properties. Architectural information isn{\textquoteright}t usually explicitly represented at runtime; developers transform and realize the architectural properties through runtime artifacts. Recently, the introduction of software platforms supporting component plug-in and dynamic binding has facilitated adaptation of software systems at runtime. Preserving the properties described by the architecture model during adaptation is an important task. We propose a self-adaptation approach that exploits architecture models to reason about and control adaptation at runtime. We can derive runtime models from design models facilitating the developers{\textquoteright} task. We developed the approach in the context of mobile computing. This article is part of a focus section on software architecture.},
	author = {Floch, Jacqueline and Svein O. {Hallsteinsen} and Stav, Erlend and Eliassen, Frank and Lund, Ketil and Gj{\o}rven, Eli}
}
@inproceedings {Amundsen.2006.3,
	title = {Utilising Alternative Application Configurations in Context- and QoS-Aware Mobile Middleware},
	journal = {6th IFIP International Conference on Distributed Applications and Interoperable Systems (DAIS{\textquoteright}06), June 13-16, Bologna, Italy},
	year = {2006},
	month = {June},
	pages = {228-241},
	publisher = {Lecture Notes in Computer Science, Vol. 4025, Springer Verlag},
	type = {1},
	abstract = {State-of-the-art dynamic middleware uses information about the environment in order to evaluate alternative configurations of an application and select one, according to some criteria. In the context of applications sensitive to Quality of Service, we have identified the need for a platform-independent description of configurations that includes non-functional behaviour, and that scales to handle a large number of application configurations. In this paper, we present a modelling principle and a service plan concept, which together represent such as description. The modelling principle and plan concept extends state-of-the-art with i) a model of the alternative configurations that ensure a minimum of reconfiguration steps, ii) a specification that contains information elements of the configuration, dependencies to the environment, and QoS characteristics, and iii) a platform independent specification. In the paper, we also perform a qualitative assessment of our app roach, and we describe a proof-of-concept implementation.},
	author = {Sten Lundesgaar {Amundsen} and Lund, Ketil and Eliassen, Frank}
}
@article {Lund.2005.1,
	title = {APEX: Adaptive Disk Scheduling Framework With QoS-Support},
	journal = {ACM Multimedia Systems Journal},
	volume = {11},
	number = {1},
	year = {2005},
	month = {November},
	pages = {45-59},
	abstract = {APEX is an adaptive disk scheduling framework with QoS (Quality-of-Service) support, designed for environments with highly varying disk bandwidth usage. APEX is based on a three-layer scheduling architecture: (1) the upper layer realizes different service classes using a set of queues; (2) the mid-layer distributes available disk bandwidth among these queues; and (3) the lower layer is handled by the disk itself, which does the final ordering of disk requests. We demonstrate the use of APEX in an example scenario, a Learning-on-Demand application supported by a multimedia system, where students can search for, and play back multimedia-based learning material. In this paper, we present the scheduling concepts of APEX, which are based on an extended token bucket algorithm. The disk requests scheduled for service are assembled into batches, in order to exploit the intelligence of modern disks. Combined with a specialized work-conservation scheme, this enables APEX to apply bandwidth where it is needed, without loss of efficiency. We demonstrate, through simulations, that APEX provides both higher throughput and lower response times than other mixed-media disk schedulers, while still avoiding deadline violations for real-time requests. We also show its robustness with respect to misaligned bandwidth allocation.},
	author = {Lund, Ketil and Goebel, Vera and Plagemann, Thomas}
}
@inproceedings {Amundsen.2005.1,
	title = {QoS-Aware Mobile Middleware for Video Streaming},
	journal = {31st EUROMICRO Conference on Software Engineering and Advanced Applications (SEAA), Portugal August 30-September 3},
	year = {2005},
	month = {September},
	pages = {54-61},
	publisher = {IEEE Computer Society},
	type = {1},
	author = {Sten Lundesgaar {Amundsen} and Lund, Ketil and Griwodz, Carsten and Halvorsen, P{\r a}l}
}
@article {Halbo.2005.1,
	title = {Quality Management Education Over the Internet},
	journal = {Accreditation and Quality Assurance},
	volume = {10},
	number = {3},
	year = {2005},
	month = {February},
	pages = {116-120},
	author = {Halbo, Leif and Lund, Ketil and Hans Arne {Fr{\o}ystein}}
}
@inproceedings {ND.5.Amundsen.2004,
	title = {QuA: Platform-Managed QoS for Components Architectures},
	journal = {Proceedings of Norwegian Informatics Conference (NIK)},
	year = {2004},
	month = {November},
	publisher = {Tapir},
	type = {1},
	author = {Amundsen, S. and Lund, Ketil and Eliassen, Frank and Staehli, Richard}
}
@article {halvorsen-dsonline-2004a,
	title = {Storage System Support for Continuous-Media Applications, Part 1: Requirements and Single-Disk Issues},
	journal = {IEEE Distributed Systems Online},
	volume = {5},
	number = {1},
	year = {2004},
	month = {January},
	author = {Halvorsen, P{\r a}l and Griwodz, Carsten and Goebel, Vera and Lund, Ketil and Plagemann, Thomas and Walpole, Jonathan}
}
@article {halvorsen-dsonline-2004b,
	title = {Storage System Support for Continuous-Media Applications, Part 2: Multiple Disks, Memory, and Integration},
	journal = {IEEE Distributed Systems Online},
	volume = {5},
	number = {2},
	year = {2004},
	month = {February},
	author = {Halvorsen, P{\r a}l and Griwodz, Carsten and Goebel, Vera and Lund, Ketil and Plagemann, Thomas and Walpole, Jonathan}
}
@phdthesis {ND.3.Lund.2003,
	title = {Adaptive Disk Scheduling in a Multimedia DBMS},
	year = {2003},
	month = {December},
	school = {Department of Informatics, University of Oslo},
	type = {phd},
	abstract = {In the last years, Internet access methods such as xDSL and cable modems have become much cheaper in Europe, and the result is that broadband network access is becoming more and more widespread. Consequently, online multimedia services like News-on-Demand (NoD), digital libraries and Learning-on-Demand (LoD) are becoming important elements of the information society. The scenario of our work is a LoD-system, where a multimedia database management system (MMDBMS) realizes a large repository for multimedia-based learning material. Teachers create multimedia presentations consisting of combinations of multimedia objects, while the students search for and play back these presentations. Consequently, the MMDBMS must handle a constantly shifting workload, with very diverse requirements; and because the large size of the multimedia data implies that secondary storage must be used, these requirements are also imposed on the storage subsystem. In this thesis, we show that disk scheduling is an effective way of meeting these storage subsystem requirements. We have developed a disk scheduling framework called APEX (AdaPtive disk-schEduler for mixed-media workloads), which is specifically targeted at the requirements of a MMDBMS-based LoD-system. APEX is able to provide a number of different service types, support QoS, and at the same time achieve very high disk utilization. This has been made possible through the use of the following four techniques: (1) dynamic queue management, which keeps the overhead of the scheduling framework low, and updates bandwidth reservations according to the requirements of the MMDBMS; (2) an extended token bucket model, which ensures accurate distribution of disk bandwidth; (3) a batch building principle, which submits disk requests in batches, and ensures high disk utilization; and (4) a work-conservation feature that re-distributes unused disk bandwidth without loss of disk efficiency. We have implemented APEX together with two other disk schedulers in a simulation environment. Our measurements show that for best-effort disk requests, APEX achieves approximately 30\% higher throughput and from 30\% to 90\% lower response times than comparable schedulers, while providing the equal QoS-guarantees for real-time requests. In addition, our analysis shows that APEX does not impose any higher computational complexity than other disk schedulers offering multiple service types. From our simulations, it is also clear that APEX is able to handle the extensively shifting MMDBMS workload; it makes sure that the disk bandwidth is distributed according to the reservations that are made, and then re-distributes unused bandwidth to where it is needed. In addition, APEX is designed to take advantage of the intelligence of modern disks, leaving the final ordering of requests to the disk itself, and thereby further increasing the disk utilization. Consequently, our disk scheduling framework is well suited for a demanding environment like a MMDBMS. However, due to its modularity and dynamic configurability, APEX is also well suited for a wide range of other applications, whether they require real-time service, high-throughput, low-latency, or any combination of these.},
	author = {Lund, Ketil}
}
@inproceedings {ND.5.Lund.2003,
	title = {Adaptive Disk Scheduling in a Multimedia DBMS},
	journal = {ACM Multimedia Conference (ACM MM{\textquoteright}03)},
	year = {2003},
	month = {December},
	pages = {65-74},
	publisher = {ACM Press},
	type = {1},
	address = {Berkeley, CA, USA},
	abstract = {In this paper, we present APEX, a disk scheduling framework with QoS support, designed for environments with highly varying disk bandwidth usage. In particular, we focus on a Learning-on-Demand scenario supported by a multimedia database management system, where students can search for, and play back multimedia-based learning material. APEX is based on a two-level scheduling architecture, where the upper level realizes different service classes using a set of queues, while the lower level distributes available disk bandwidth among these queues. In this paper, we focus on the low-level scheduling in APEX, which is based on an extended token bucket algorithm. The disk requests scheduled for service are assembled into batches, which render possible good efficiency for the disk. Combined with a very efficient work-conservation scheme, this enables APEX to apply bandwidth where it is needed, without efficiency loss. We demonstrate, through simulations, that APEX provides both higher throughput and lower response times than other mixed-media disk schedulers, while still avoiding deadline violations for real-time requests. We also show its robustness with respect to misaligned bandwidth allocation.},
	author = {Lund, Ketil and Goebel, Vera}
}
@techreport {ND.7.Halorsen.2003,
	title = {Storage System Support for Multimedia Applications},
	number = {307},
	year = {2003},
	note = {ISBN 82-7368-259-5},
	month = {June},
	publisher = {Department of Informatics, University of Oslo},
	author = {Halvorsen, P{\r a}l and Griwodz, Carsten and Lund, Ketil and Goebel, Vera and Plagemann, Thomas}
}
@inproceedings {ecklund01,
	title = {QoS Management Middleware: a Separable, Reusable Solution},
	journal = {Proceedings of the International Workshop on Interactive Distributed Multimedia Systems and Telecommunication Services (IDMS)},
	year = {2001},
	month = {sep},
	pages = {124-137},
	publisher = {Springer-Verlag},
	type = {Conference},
	isbn = {3-540-42530-6},
	author = {Ecklund, Denise and Goebel, Vera and Plagemann, Thomas and Ecklund, Earl and Griwodz, Carsten and Jan {\O}yvind {Aagedal} and Lund, Ketil and Berre, Arne-Jorgen},
	editor = {Shepherd, Doug and Finney, Joe and Mathey, Laurent and Nicolas J. P. {Race}}
}
@inproceedings {ND.5.Lund.2000,
	title = {Requirements Analysis and Design for a Flexible Learning-on-Demand System},
	journal = {World Conference on Integrated Design and Process Technology (IDPT 1999)},
	year = {2000},
	publisher = {SDPS},
	type = {1},
	address = {Dallas, TX, USA},
	author = {Lund, Ketil and Halvorsen, P{\r a}l and Goebel, Vera and Plagemann, Thomas}
}
@inproceedings {Halvorsen.1999.1,
	title = {ConfMan: Integrated WWW and DBS Support for Conference Organization},
	journal = {Poster Proceedings of The Eighth International World Wide Web Conference (WWW{\textquoteright}8)},
	year = {1999},
	month = {May},
	publisher = {Elsevier},
	type = {1},
	author = {Halvorsen, P{\r a}l and Lund, Ketil and Goebel, Vera and Plagemann, Thomas and Preuss, Thomas and Koenig, Harmut}
}
@inproceedings {ND.5.Goebel.1999,
	title = {Design, Implementation, and Evaluation of TOOMM: a Temporal Object-Oriented Multimedia Data Model},
	journal = {Proceedings of the 8th IFIP 2.6 Working Conference on Database Semantics (DS-8),Semantic Issues in Multimedia Systems},
	year = {1999},
	month = {January,},
	pages = {145-168},
	type = {1},
	address = {Rotorua, New Zealand},
	author = {Goebel, Vera and Eini, I. and Lund, Ketil and Plagemann, Thomas}
}
@inproceedings {ND.5.Goebel.1998,
	title = {Towards QoS Support in Multimedia Database Management Systems (Poster)},
	journal = {The 6th ACM Multimedia Conference 98},
	year = {1998},
	month = {September,},
	pages = {52-54},
	publisher = {ACM},
	type = {1},
	address = {Bristol, UK},
	author = {Goebel, Vera and Halvorsen, P{\r a}l and Lund, Ketil and Mirzadeh, N. and Plagemann, Thomas}
}
