This thesis describes the theoretical and practical stages through development to testing of an integrated navigation system, specifically composed of an Inertial Navigation System (INS), and Global Positioning System (GPS). Integrated navigation systems combine the best features of independent systems to bring out increased performance, improved reliability and system integrity. In an integrated INS/GPS system, INS output is used to calculate current navigation states / GPS output is used to supply external measurements, and a Kalman filter is used to provide the most probable corrections to the state estimate using both data. Among various INS/GPS integration strategies, our aim is to construct a tightly coupled integrated INS/GPS system. For this purpose, mathematical models of INS and GPS systems are derived and they are linearized to form system dynamics and system measurement models respectively. A Kalman filter is designed and implemented depending upon these models. Besides these, based on the given aided navigation system representation a quantitative measure for observability is defined using Gramians. Finally, the performance of the developed system is evaluated with real data recorded by the sensors. A comparison with a reference system and also with a loosely coupled system is done to show the superiority of the tightly coupled structure. Scenarios simulating various GPS data outages proved that the tightly coupled system outperformed the loosely coupled system from the aspects of accuracy, reliability and level of observability.

The thesis explores middle managers sensemaking processes of a University’s social responsibility and sustainability (SRS) strategy during a period of change. Overall the thesis establishes links between middle managers simultaneous sensemaking processes, dynamics of loosely coupled organizational contexts and organizational responses to unexpected outcomes as they impact strategy creation processes in organisations. Three main issues evolve. Firstly, middle managers in loosely coupled organisations consist of two different sets (administrators and academics). Based on their nature of work in particular, administrators and academics select different sets of dominant and subtle sensemaking frames to make sense of organizational strategies. Generally, while administrators select sensemaking frames which emanate from existing strategic processes, academics select autonomous cues which exist outside strategic processes. Administrators and academics sensemaking processes are therefore not a single level or consecutive processes as typically researched, but rather occur as simultaneous sensemaking processes. Six dominant simultaneous sensemaking frames are identified and described. Secondly, the thesis examines less explored aspects of debates on loosely coupled systems. It investigates specific patterns of coupledness in middle managers strategic work and relationships. It identified and described patterns of administrative work which are tightly coupled and patterns in academic work which are loosely coupled. Thirdly, distinct links are identified between middle managers simultaneous sensemaking processes and unexpected strategy outcomes. This further led to exploring how organizations respond to unexpected sustainability initiatives, especially in light of integrating them into already existing strategy outcomes. Three integration strategies are identified and described.

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Transfer signal without wire has been widely accepted after the introduction of cellular technology and WiFi technology, hence the power cable is the last wire that has yet to be eliminated. Inductive power transfer (IPT) has drawn substantial interest in both academia and industry due to its advantages including convenience, nonexistence of cable and connector, no electric shock issue, ability to work under some extreme environment, and so on. After performing thorough literature review of IPT systems, two major drawbacks including low power efficiency and coil displacement sensitivity are identified as the main obstacles that have to be solved in order for these systems to reach full functionality and compete with existing wired solutions. To address the limitations and design challenges in the IPT systems, a detailed electric circuit modeling of individual part of the IPT DC-DC stage is performed. Several resonant DC-AC inverters and output AC-DC rectifiers are compared based on their performance and feasibility in inductive charging applications. Different equivalent circuit models for the loosely coupled transformer (LCT) are derived which allows for better understanding on how power is distributed among the circuit components. Five compensation networks to improve the power transfer efficiency are evaluated and their suitable application occasions are identified. With comprehensive circuit model analysis, the influence of the resonant compensation tank parameters has been investigated carefully for efficient power transfer. A novel tuning network parameters design methodology is proposed based on multiple given requirement such as battery charging profile, geometry constraints and operating frequency range, with the aim of avoiding bifurcation phenomenon during the whole charging process and achieving decent efficiency. A 4-kW hardware prototype based on the proposed design approach is built and tested under different gap and load conditions. Peak IPT system DC-DC efficiencies of 98% and 96.6% are achieved with 4-cm and 8-cm air gap conditions, which is comparable to the conventional plug-in type or wired charging systems for EVs. A long-hour test with real EV batteries is conducted to verify the wireless signal transmission and CC/CV mode seamless transition during the whole charging profile without bifurcation. To reduce the IPT system sensitivity to the gap variation or misalignment, a novel LCT design approach without additional complexity for the system is proposed. With the aid of FEA simulation software, the influence of coil relative position and geometry parameters on the flux distribution and coupling coefficient of the transmitter and receiver is studied from an electromagnetic perspective. An asymmetrical LCT based on the proposed design method is built to compare with a traditional symmetrical LCT. With fixed 10-mm gap and 0 to 40-mm misalignment variation, the coupling coefficient for the symmetrical LCT drops from 0.354 to 0.107, and the corresponding efficiency decrease is 16.6%. The operating frequency variation is nearly 100 kHz to maintain same input/output condition. When employing the proposed asymmetrical LCT, the coupling coefficient changes between 0.312 and 0.273, and the maximum efficiency deviation is kept within 0.67% over the entire 40-mm misalignment range. Moreover, the required frequency range to achieve same operation condition is less than 10 kHz. Lastly, some design considerations to further improve the IPT system efficiency are proposed on the basis of the designed asymmetrical LCT geometry. For given circuit specifications and LCT coupling conditions, determination of the optimal primary winding turns number could help achieve minimal winding loss and core loss. For lower output power, the optimal primary winding turns number tends to be larger compared to that for higher output power IPT system. Two asymmetrical LCT with similar dimension but different number of turns are built and tested with a 100-W hardware prototype for laptop inductive charging. The proposed efficiency improvement methodology is validated by the winding loss and core loss from experimental results. / Ph. D.

Camera based navigation is getting more and more popular and is the often the cornerstone in Augmented and Virtual Reality. However, navigation systems using camera are less accurate during fast movements and the systems are often resource intensive in terms of CPU and battery consumption. Also, the image processing algorithms introduce latencies in the systems, causing the information of the current position to be delayed. This thesis investigates if a camera and an IMU can be fused in a loosely coupled Extended Kalman Filter to reduce these problems. An IMU introduces unnoticeable latencies and the performance of the IMU is not affected by fast movements. For accurate tracking using an IMU it is important to estimate the bias correctly. Thus, a new method was used in a calibration step to see if it could improve the result. Also, a method to estimate the relative position and orientation between the camera and IMU is evaluated. The filter shows promising results estimating the orientation. The filter can estimate the orientation without latencies and can also offer accurate tracking during fast rotation when the camera is not able to estimate the orientation. However, the position is much harder and no performance gain could be seen. Some methods that are likely to improve the tracking are discussed and suggested as future work.

Bakgrund I det närmaste alla organisationer strävar efter att använda sina resurser så effektivt som möjligt. Vad som dock inte diskuterats i någon större utsträckning är att den starkt kopplade komplexa organisationen inte klarar av att bemöta ens den minsta avvikelsen utan att ägna den direkt uppmärksamhet. Den övergripande frågan är därför Hur hanteras avvikelser i starkt kopplade projekt? Det teoretiska ramverket är först och främst projektlitteratur men ramverket vidgas sedermera till att omfatta praktikansatslitteratur samt Weicks (1976) ”Loosely coupled systems”. Metod Givet ansatsen faller det sig naturligt att göra en fallstudie med observationer som huvudsaklig metod. Utöver tolv veckors observationer förlitar jag mig på 57 intervjuer och mängder av dokument. En organisation, två projektgrupper och 118 avvikelser observerades totalt under perioden. De data som samlades in analyserades med hjälp av dataprogrammet Nvivo. Resultat Analysen är uppdelad i tre integrerade kapitel. Det första kapitlet diskuterar avvikelser som företeelse och definierar begreppet närmare. En avvikelse definieras som en händelse som kräver såväl identitet som handlingskraft. Det andra analyskapitlet analyserar praktiken närmare. Allt som allt observerades 29 praktiker vilka kunde grupperas i åtta praktikmönster. Praktikmönstren kunde sedermera inordnas i två distinkta löskopplingsmönster i en teoretiskt underbyggd och empiriskt styrkt figur. Figuren och följaktligen praktikmönstren beskriver hur avvikelsen görs löst kopplad. Det tredje analyskapitlet diskuterar fem mekanismer som följer av med de löst kopplade avvikelserna. Dessa fem mekanismer kan sedermera betonas och utnyttjas av projektledaren. Slutsatser Slutsatserna följer två spår. Det ena spåret fokuserar på projekt i allmänhet och projektledning i synnerhet. Slutsatsen som kan dras där är att det finns en inneboende osäkerhet i projekt som kan utnyttjas för att hantera avvikelser. Alla avvikelser har inte stora konsekvenser men de besitter vissa gemensamma egenskaper. Det andra spåret är ett bidrag till teorin om löst kopplade system. Länge har en processuell och praktikbaserad studie saknats. Genom att undersöka löskopplingsprocesser i ljuset av en praktikansats har jag visat hur löskopplingsprocesser ser ut.

In this thesis a 3-D Euler flow solver is coupled with a finite element program in order to solve static aeroelastic problems involving aircraft wings. A loosely coupled solution approach based on an iterative solution procedure is used to solve the coupled field problem. Because of the deformation of the underlying surface over which the flow is solved, Computational Fluid Dynamics mesh has to move at each computational aeroelastic iteration in order to comform to the new shape of the aerodynamic surface. As a part of this work, a procedure is developed in order to move fluid grid points, which views the whole computational domain as an isotropic elastic medium and solves it using finite element method. A matching discrete interface is defined / displacement and pressure data exchange is accomplished at this interface. AGARD Wing 445.6 and an elastic supercritical wing is modelled and solved with the developed computational aeroelastic procedure and the obtained results are compared with numerical and wind tunnel data.

abstract: The purpose of this study was to explore features of Supplemental Educational Services (SES) implementation at the district level. In the study beliefs, goals, and actions of district office administrators were analyzed against the backdrop of changing federal guidelines and challenges faced by SES implementers across Arizona. The case study focuses on implementation in the 2007-2008, 2008-2009, and 2009-2010 school years. The study uses the 2005 and 2009 Department of Education guidelines, survey responses from Arizona district and school implementers, as well as documents and interviews from an urban Arizona case district. The study separates the implementation activities into task areas, which are analyzed separately. Using a loose coupling perspective, the separate task areas are furthered used as coupling domains and represented in social network graphs. Results show that the case district personnel were highly focused on their primary role, maintaining district compliance with federal guidelines. The district personnel employed several changes over the case study period to centralize their control of SES operations within district. The employment and training of site level coordinators was the most impactful of the strategies. As boundary spanners, the coordinators allowed greater access to information, oversight, and influence at the site level. Despite the growing capacity and earnest efforts of the district personnel, the case district was still very far from being able to measure or assess the impact of SES on student achievement. Centralization in the scholastic task areas was relatively low, and had marginal changes over the case study period. Years into the program, there was still no avenue to accurately gauge the effectiveness. As the district personnel were chiefly concerned with compliance, they had suspended judgment on the program and focused primarily on improving their processes. / Dissertation/Thesis / Ph.D. Educational Leadership and Policy Studies 2011

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