This study is about the coordination of complex systems’ development. A Framework has been designed and deployed by the author in the development practice of Ericsson, a major supplier of telecommunication systems on the global market. The main purpose of the study is to investigate the impacts on coordination from the Framework. The development projects are very large and subject to turbulent market conditions. Moreover, they have many participants (often several thousand), have tight time constraints and are distributed to many design centres all over the world. In these projects, coordination of the development is of crucial importance. The Framework is grounded in a tentative theory called the Activity Domain Theory, which in turn is based on the praxis philosophy. In this theory the interaction between the individual and her environment is mediated by signs. Coordination is conceived as a particular activity domain which provides coordination to the development projects. The coordination domain is gradually constructed by the actors in this domain by iteratively refining a conceptual model, a process model, a transition model, a stabilizing core and information system support. In this process individual knowledge, shared meaning and organizational artefacts evolve in a dialectical manner. The Framework has been introduced in the Ericsson development practice over a period of more than ten years. Between 1999 and 2002 approximately 140 main projects and sub-projects at Ericsson have been impacted by the Framework. These projects were distributed to more than 20 different development units around the world and were carried out in a fiercely turbulent environment. The findings indicate that the Framework has had a profound impact on the coordination of the development of the most complex nodes in the 3rd generation of mobile systems. The knowledge contributions include an account for the history of the Framework at Ericsson and an identification of elements which contribute to successful outcomes of development projects. / The electronic version of the printed dissertation is a corrected version where all spelling and grammatical errors are corrected. Errors in tables has been corrected as in the errata above.

Microwave telecommunication systems employ a large number of waveguide components operating at microwave and millimeter-wave frequencies. Accurate design of these components for optimum performance of the overall system is critical and, therefore, computationally efficient and accurate numerical methods are indispensable. The objective of this work is to develop a framework for the computer-aided analysis and design of microwave components containing cross sections with arbitrarily positioned ridges. A new formulation to obtain the eigenmode spectra of irregular waveguides is presented. The method uses modified modes of regular waveguide housings as expansion terms and leads to a classical eigenvalue problem. A constraint function is introduced to satisfy the boundary conditions for TM modes; TE modes are obtained straightforwardly. This procedure is then combined with a mode-matching code in order to analyze and optimize waveguide structures involving resonating components. The general approach is applied to multiple ridged waveguide structures in rectangular and circular waveguide technologies. Convergence is demonstrated, and applicability of the developed algorithm is tested through the design of waveguide filters, transformers, polarizers and polarization-rotating components. Two new configurations of circular T-septum and key-shaped below-cutoff filters are introduced. Whenever possible, the designs are validated by independent means. Excellent agreement is obtained between the approach presented in this thesis and other full-wave field solvers.

Dissertation (PhD)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Though not so prominent as the wide band, high speed, mainstream development of data communication networks, cost and particular bandwidth limitations, still ensure extensive and continuing use of low-speed, half-duplex data link equipment. Most of these applications are radio based and aimed towards telemetry systems serving a wide range of utilities. Experience has shown that systems engineering for this type of installation, is seldom undertaken to a satisfactory analytical level. Investigation of published analyses of CSMA protocols in general, has indicated scope of extension of theoretical work to include system parameters for the type of protocol investigated in this dissertation. This dissertation describes the mathematical modeling of such a strategy by utilising a significantly modified, finite source, transition state-matrix approach derived from queueing theory. The contribution of the dissertation is to include system overhead parameters, such as backoff strategy, channel noise, equipment rise times, propagation- and retry delays, into the abovementioned model. The latter provides a relatively straightforward and readily applicable method for system analysis and performance prediction. A further contribution is the presentation of a software emulation with which different strategies could be simulated, allowing for adjustment of all design parameters. The simulation is intended for parallel and confimatory use with the theoretical model. A dual set of tools, theoretical and emulation based, is thus contributed to assist with the system design, performance prediction and protocol selection process. / AFRIKAANSE OPSOMMING: Alhoewel nie so prominent soos die wyeband, hoëspoed, hoofstroom ontwikkeling van datakommunikasie netwerke nie, verseker koste en spesifieke bandwydte beperkings nog die uitgebreide en voortdurende gebruik van laespoed half-dupleks data verbindingstoerusting. Meeste van die toepassings is radio gebaseer en gerig op telemetriestelsels wat deur 'n wye verskeidenheid diensverskaffers benut word. Stelselontwerp vir hierdie tipe installasies word selde op analitiese vlak benader. Ondersoek van gepubliseerde analises van kontensieprotokolle in die algemeen, het ruimte aangetoon vir die uitbreiding van bestaande teoretiese werk om stelselveranderlikes soos van toepassing op die tipe protokol in hierdie proefskrif ondersoek, in te sluit. Hierdie proefskrif beskryf die wiskundige modelering van sodanige strategie, deur gebruik te maak van 'n beduidend veranderde eindige bron, oorgangs-toestandmatriks benadering, afgelei van touteorie. Die bydrae van hierdie proefskrif is die insluiting van oorhoofse stelselveranderlikes, soos herhaal strategie, kanaalruis, toerusting stygtye, herhaal- en voortplantingsvertragings, in bogenoemde model. Laasgenoemde verskaf 'n relatief eenvoudige en maklik toepasbare metode vir stelselanalise en werkverrigtingvoorspelling. 'n Verder bydrae is die daarstelling van 'n sagteware simulasie waarmee verskillende strategieë nageboots kan word. Verstelling van alle ontwerpparameters word ondersteun. Die simulasie is bedoel vir parallelle en bevestigende gebruik tesame met die teoretiese model. 'n Dubbele, teoreties- en simulasie gebaseerde benadering, word dus aangebied vir gebruik by stelselontwerp, gedragsvoorspelling en optimale protokolseleksie.

Thesis (M.S.)--Kutztown University, 1989. / Source: Masters Abstracts International, Volume: 45-06, page: 2701. Typescript. Includes bibliographical references (leaves 60-62).

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Electrical Engineering, Thomas J. Watson School of Engineering and Applied Science, 2006. / Includes bibliographical references.

Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Laskar, Joy; Committee Member: Chang, Jae Joon; Committee Member: Cressler, John D.; Committee Member: Kornegay, Kevin T.; Committee Member: Lee, Chang-Ho; Committee Member: Tentzeris, Manos M.. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Raghupathy, Sivakumar; Committee Member: Farmarz Fekri; Committee Member: Mary Ann, Ingram. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 128-132). Also available via the Internet.

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, March 2005. / Thesis Advisor(s): John C. McEachen. Includes bibliographical references (p. 51-53). Also available online.

Thesis (Ph. D.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Electrical Engineering, 2008. / Includes bibliographical references.