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Product Lifecycle Management (PLM) systems are used by thousands of engineering companies world wide. Improving these systems will have a drastic and global effect. One possible improvement is to integrate synchronous collaborative applications with PLM systems. These applications allow multiple people to work on a single digital object simultaneously. They have already been shown to reduce the time a task requires. Using these applications to complete a project will reduce the project time. However, simply including synchronous collaborative applications within a PLM system ignores powerful benefits that could provide further time-saving benefits. The integration must allow improved awareness at the project level, so that users can mediate their own actions.This thesis presents a method for such an integration. It also presents a prototype which implements that method. Testing was carried out using this prototype. As hypothesized, including synchronous collaborative applications shortened the overall project time. In addition, providing awareness information and allowing users to mediate themselves further shortened project times and reduced variation in those times. Proper integration should therefore provide awareness at the project level and allow users to mediate themselves to some extent.

HLA is a standard for distributed simulations where many small simulations connect to each other to create a bigger simulation. As networking technologies have evolved the requirements for the simulations. This includes running certain simulations to communicate over Wide Area, 4G, and 5G networks. The Federate Protocol has been purposed as a solution giving the simulations a client-server model. Currently simulations send requests and wait for the responses which results in performance losses as the simulation waits for the Round Trip of the request. Therefore an Asynchronous solution has been purposed to solve this performance issue. To make sure the simulations do not send to many requests and overwhelm the server Flow Control is needed. This paper will compare the performance of Synchronous and Asynchronous modes and look at what kinds of Flow Control methods can be used and their behaviors

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Due to the loose coupling nature and separated primary/secondary side, achieving tight load regulation or implementing closed-loop control of output voltage/current is nontrivial in a wireless power transfer (WPT) system. Previously presented methods for regulating or controlling the output of a WPT system include incorporating either post-regulator stage, wireless communication from secondary to primary side, primary side sensing and modulation scheme, or dual active bridge type of topology. However, all existing methods have limitations and disadvantages in terms of increased size/cost, control complexity, or reliability in electrically noisy environments. This dissertation proposes a single switch control and regulation mechanism based on the secondary side of the WPT system. Specifically, the duty cycle of the secondary side synchronous rectifier (SR) switch is modulated to control the output voltage or current. By modulating the SR duty cycle, output of the WPT system can be controlled without requiring additional regulator stages/power devices, a primary side sensing mechanism, or secondary to primary communication. The proposed control method lowers cost and simplifies the design of WPT systems while improving reliability in noisy environments. The proposed control and modulation mechanism maintains zero voltage switching of all power semiconductor switches so efficiency of the WPT system would not be compromised by implementing the proposed control scheme. The proposed secondary side SR based control method can be applied to dc-dc WPT systems to control output voltage or current, or it could be used in a dc-ac WPT system to generate and regulate ac output if combined with an unfolding stage. When used in dc-ac WPT systems, the bulky output filter stage usually required in conventional dc-ac inverters is eliminated. The proposed control scheme is evaluated with computer simulation as well as hardware implementation and testing. / Doctor of Philosophy / Wireless power transfer (WPT) is an emerging technology that supplies electric power to loads without using wires or electrical contacts. WPT technology has many promising uses in consumer, industrial, transportation, biomedical, and other applications. However, unlike controlling the output voltage of a conventional power supply or power converter, controlling the output of a WPT system is not a simple task due to the physical separation between the transmitting and receiving sides. State-of-the-art methods for controlling the output of a WPT system include adding another power regulator stage to regulate output, incorporating secondary side (power receiver) to primary side (power transmitter) communication so that output information can be passed back to the primary side where that information is used to monitor and regulate output. In some systems, output information may also be estimated indirectly from primary side voltage/current information. However, all these methods have significant disadvantages. Adding another power converter stage increases cost and efficiency loss of the WPT system. Incorporating secondary to primary communication for output control is detrimental to the reliability of the PWT system because communication may be impacted by external noise. The reliability of primary side sensing and regulation is also severely impacted by component parameter variations in the WPT system. This dissertation proposes a new mechanism that controls output of a WPT system at the receiver or secondary side without needing another power conversion stage, communication or any cooperation from primary side. The proposed control mechanism controls the turn on duration of the synchronous rectifier (SR) switch at the receiver side to modulate output voltage or current. Since SR technology is already prevalently used in power electronics systems, including WPT systems, to efficiently convert high frequency ac to dc before delivering power to the load, implementing the proposed control mechanism does not increase complexity or cost of the WPT system. The proposed control mechanism is useful in both dc-dc and dc-ac WPT systems. In a dc-dc WPT system, the proposed mechanism can control or regulate output voltage or current independently from the primary side, while in a dc-ac WPT system the proposed mechanism can generate and regulate ac output. If used in a dc-ac WPT system an unfolding stage needs to be added, but the bulky output filter stage required in conventional pulse width modulation (PWM) dc-ac inverters for suppressing switching ripple is not needed. The proposed mechanism is verified with computer simulation as well as hardware prototyping in this dissertation.

A microprocessor control scheme for variable speed switched reluctance motor(SRM) drives is discussed. A particular implementation derived from first principles of the SRM is presented. The Intel 8088 microprocessor is used for the design implementation. It is shown that given the control requirements of the SRM like firing different phases according to rotor position and phase currents, a microprocessor controller is a good choice. The controller is economical since it uses standard TTL chips. The slow response at low speeds is also discussed. Experimental results performed on a static inductive load using a simulated position feedback are presented, showing how the current control available at lower speeds is lost at higher speeds, due to limited dc bus voltage. A listing of the controller software with adequate comments and the circuit diagrams are appended. / Master of Science

As laptop mobile users expect more application features and long battery life, the processor current has to increase to response the demanding while the voltage has to decease to save the power loss. Therefore, it is necessary for a system designer to improve the efficiency of the voltage regulator converter (VRC) for the processor. Laptop processor architecture is more complicated than desktop because of different mode operations and their transitions. The laptop processor runs at different voltage levels for each operation mode to save the battery life. Therefore, the VRC needs to supply the correct and stable voltage to the processor. In this thesis, an analysis of power loss is derived to estimate the efficiency and switching frequency, three widely current sensing methods are discussed, two methods to compensate for the thermal resistance in loss less current sense methods are proposed, the tolerance of load line base on the component's tolerance in the converter is analyzed, the equation to estimate the output capacitance is derived, and the small signal analysis of multiphase synchronous buck converter with the droop current loop is derived. A hardware prototype was implemented base on 4-phase synchronous buck topology to provide high efficiency and lower cost solution. The results of load line meets the Intel specification in different modes of operation, provides the best transient responses, and meets the specification during the load transient. The control loop lab measurement is also matched with the analysis and simulation. / Master of Science

The sideband phenomenon is a common but obscure characteristic of the Rotary Dynamics field. In the automotive industry these sidebands have been found to produce a poor sound quality, resulting in customer dissatisfaction and warranty returns. In the interest of continued product improvement, research and development must resolve uncertainties in the current design methods. Qualitative relationships between the sideband characteristics and design parameters have developed in recent years, but the quantitative goal hasn't been achieved. A Synchronous Sampling (SS) data acquisition system is applied to a helical planetary gear set to improve the understanding of the sideband characteristics and enhance the design process. An optical encoder, a component of the SS system, mechanically locked to the rotating system controls the A/D converter to sample at constant shaft angle increments. The phase-locked nature of SS allows the use of vector averaging to significantly lower the noise floor and improve the representation of the order domain. In this work, the advantages of using a SS system with vector averaging capabilities are compared to the disadvantages of using a fixed sampling (FS) system. Utilizing the SS tool, this work also illustrates the influences of loading styles and values and speed on a gearmesh and its dominant sideband orders. Inspection of these influences suggests an opportunity for future work. / Master of Science

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