The focus in this project is on machine guards, which will be improved andmade more secure for efficiency and safety. The aim is to design machine guardswith a vertical opening panel for simpler machine access. The work iscorporated with Axelent Engineering in order to meet all standards withsustainability and quality to protect humans and the machine. The aim of thisproject is to examine the specified X-guards to open vertically with the height of1300 mm in order to generate a product that meets the specified standards. Thepurpose of this task is to develop a product that will meet the technicalrequirements and safety standards in order to permit vertical opening for AxelentEngineering’s X-guards.As for the result, the concept generated for the X-guard operates with linearbearings and counterweights, the concept is later presented to AxelentEngineering for manufacturing or further development. The result of the finalconcept is the most suitable of all the concepts generated, proven by usingselection methods.

Despite being the world’s second most important low-carbon source of electricity, the development of nuclear capacities is limited and does not comply with the International Energy Agency’s Sustainable Development Scenario. One of the main reasons for this lack of development is high and increasing costs of new nuclear capacities. In fact, capital costs can account for more than 80% of the Levelized Cost of Energy of a new nuclear power plant. Design accounts for about 10% and construction accounts for about 20% of the total capital cost.The importance of design and construction in nuclear power plants’ costs is partly due to limitations of traditional construction methods regarding both technical possibilities and realization schedules. Modular construction methods are proposed to reduce new nuclear power plants’ construction costs, and in particular steel-plate composite structures modular construction. Steel-plate composite structures consist of a structural interaction between thin steel plates and precast concrete. The aim of this thesis was to evaluate the capacity of modular construction, using steel-plate composite panels, to fulfil nuclear safety and functional requirements; as well as to identify potential related gains and opportunities. Advantages and constraints of steel-plate composite modules were identified in scientific literature and intergovernmental opportunity studies, and were related to the specificities of nuclear structures’ design and construction.Steel-plate composite structures modular construction is based on the manufacturing of steel concrete composite modules outside of the civil works site. The higher productivity of workshops and the possible task parallelization may lead to significant construction schedules shortening and capital costs reduction. In addition, steel-plate composite modules offer new technical possibilities which may help solving some constructability issues. However, steel-plate composite structures modular construction requires a reconsideration of the traditional design and construction methods, as they imply new challenges and constraints. In particular, the modularization issue should be addressed as soon as possible in the design, and the module manufacturing capacities should be quickly identified or created in order to deliver properly manufactured modules on-time.Considering the advantages and constraints of steel-plate composite structures modular construction, it appears that steel-plate composite modules may fit advantageously most of the nuclear design requirements. However, due to the lack of feedback, it is proposed that the usage of steel-plate composite modules be limited to critical concrete structures of the containment building. In particular, it appears that the containment dome and the reactor pit construction may benefit from steel-plate composite structures construction methods.

This dissertation introduces a hierarchical optimization framework for power converter-based energy management systems, with a primary focus on weight minimization. Emphasizing modularity and scalability, the research systematically tackles the challenges in optimizing these systems, addressing complex design variables, couplings, and the integration of heterogeneous models. The study begins with a comparative evaluation of various metaheuristic optimization methods applied to power inductors and converters, including genetic algorithm, particle swarm optimization, and simulated annealing. This is complemented by a global sensitivity analysis using the Morris method to understand the impact of different design variables on the design objectives and constraints in power electronics. Additionally, a thorough evaluation of different modeling methods for key components is conducted, leading to the validation of selected analytical models at the component level through extensive experiments. Further, the research progresses to studies at the converter level, focusing on a weight-optimized design for the thermal management systems for silicon carbide (SiC) MOSFET-based modular converters and the development of a hierarchical digital control system. This stage includes a thorough assessment of the accuracy of small-signal models for modular converters. At this point, the research methodically examines various design constraints, notably thermal considerations and transient responses. This examination is critical in understanding and addressing the specific challenges associated with converter-level design and the implications on system performance. The dissertation then presents a systematic approach where design variables and constraints are intricately managed across different hierarchies. This strategy facilitates the decoupling of subsystem designs within the same hierarchy, simplifying future enhancements to the optimization process. For example, component databases can be expanded effortlessly, and diverse topologies for converters and subsystems can be incorporated without the need to reconfigure the optimization framework. Another notable aspect of this research is the exploration of the scalability of the optimization architecture, demonstrated through design examples. This scalability is pivotal to the framework's effectiveness, enabling it to adapt and evolve alongside technological advancements and changing design requirements. Furthermore, this dissertation delves into the data transmission architecture within the hierarchical optimization framework. This architecture is not only critical for identifying optimal performance measures, but also for conveying detailed design information across all hierarchy levels, from individual components to entire systems. The interrelation between design specifications, constraints, and performance measures is illustrated through practical design examples, showcasing the framework's comprehensive approach. In summary, this dissertation contributes a novel, modular, and scalable hierarchical optimization architecture for the design of power converter-based energy management systems. It offers a comprehensive approach to managing complex design variables and constraints, paving the way for more efficient, adaptable, and cost-effective power system designs. / Doctor of Philosophy / This dissertation introduces an innovative approach to designing energy control systems, inspired by the creativity and adaptability of a Lego game. Central to this concept is a layered design methodology. The journey begins with power components, the fundamental 'Lego bricks'. Each piece is meticulously optimized for compactness, forming the robust foundation of the system. Like connecting individual Lego bricks into a module, these power components come together to form standardized power converters. These converters offer flexibility and scalability, similar to how numerous structures can be built from the same set of Lego pieces. The final layer involves assembling these power converters in order to construct comprehensive energy control systems. This mirrors the process of using Lego subassemblies to build larger, more intricate structures. At this system-level design, the standardized converters are integrated to optimize overall system performance. Key to this dissertation's methodology is an emphasis on modularity and scalability. It enables the creation of diverse energy control systems of varying sizes and functionalities from these fundamental units. The research delves into the intricacies of design variables and constraints, ensuring that each 'Lego piece' contributes optimally to the bigger picture. This includes exploring the scalability of the architecture, allowing it to evolve with technological advancements and design requirements, as well as examining data transmission within the system to ensure efficient data communication across all levels. In essence, this dissertation is about recognizing the potential in the smallest components and understanding their role in the grand scheme of the system. It is akin to playing a masterful game of Lego, where building something greater from small, well-designed parts leads to more efficient, adaptable, and cost-effective energy control system designs. This approach is particularly relevant for applications in transportation systems and renewable energy in remote locations, showcasing the universal applicability of this 'Lego game' to energy management.

Genetic regulatory circuits control metabolism, development, and environmental response across all kingdoms of life. Genetic circuit engineering facilitates sustainable and efficient production of biopharmaceutical, chemical, fiber, and food products that keep humans healthy, nourished, and clothed. However, the complexity of most genetic regulatory circuits, particularly in the context of multicellular eukaryotes, often prevents them from being leveraged as tools or applied technologies with bioeconomic relevance. However, synthetic biology enables the transfer of genes, circuits, networks, and even whole chromosomes between organisms. This approach can be leveraged to port genetic circuits into simple model organisms to control existing and engineer new cellular functions. Still, porting genes to non-native contexts can affect circuit function due to unknown factors. For this reason, iterative design-build-test-learn (DBTL) cycles are necessary for optimizing circuits in new contexts. To facilitate the DBTL cycle, automation approaches can be deployed for streamlining synthetic genetic circuits optimization. Here, I provide a case study for how using synthetic biology and automation – a biofoundry approach – has facilitated engineering of the auxin signaling pathway in a synthetic yeast system. Auxin is a phytohormone involved in nearly every aspect of plant growth and development, and this striking versatility designates it as a target for biotechnology development and a candidate for engineering. First, I provide a literature review of the history of synthetic auxin engineering in yeast, a survey of tools available for expanding yeast synthetic biology, and a summary of applicable automation tools and platforms. Next, I describe and validate a platform called AssemblyTron, which deploys liquid handling robotics for DNA assembly and can serve as the foundation of a biofoundry platform. I then introduce TidyTron, which is a protocol library for automated wash and reuse of single use lab plastics to promote biofoundry sustainability. Next, I expand the AssemblyTron package by providing protocols for mutant and modular indexed plasmid library assembly. Finally, I describe a modular indexed plasmid library (toolkit) for rapid assembly of auxin circuit variants and validate it by building and optimizing an auxin circuit. / Doctor of Philosophy / Genetic mechanisms allow humans, plants, and microbes to grow, breathe, speak, and survive. The DNA that encodes these genetic mechanisms produces protein machines that make chemicals, transfer them, and respond to them in other cells. This process is called signaling, and the protein machines involved make a circuit. In biotechnology, we harness natural genetic circuits to create important products like biopharmaceuticals, food, and clothes. However, the genetic circuits that make valuable proteins/chemicals are usually located on chromosomes along with every other gene involved in building an advanced, multicellular organism (called the genome). Synthetic biology allows us to choose just the DNA that encodes a genetic circuit of interest and put it into the chromosome of a simpler organism with faster growth, smaller genome, etc., which allow us to engineer it more easily. However, transferring a gene circuit to a new organism can cause problems, and it is usually necessary to try many versions of gene circuits to find one that works. Using robots to do synthetic biology can make it faster and less error-prone, which enables more versions of the genetic circuit to be tested. Here, I describe a biofoundry approach where I combined synthetic biology and robotics to speed up the process of building and optimizing the auxin plant hormone signaling pathway. Auxin is a small molecule that plants produce and transfer throughout their leaves, stems, and roots to turn growth on or off (e.g., auxin causes plants to do things like bend towards the sun). I focus on auxin because my goal is to manipulate the auxin pathway to rationally control plant growth. First, I provide a recap of existing work in the field of auxin synthetic biology, tools for transferring auxin circuits into simpler organisms, and available robotics that can speed up auxin synthetic biology. Next, I introduce a software called AssemblyTron, which I developed for building and modifying genes (a process called DNA assembly) with a robot. Next, I discuss how I used the same robot to wash and reuse plastic pipette tips and plates to improve lab sustainability. I then discuss an extended version of AssemblyTron that can be used for more advanced DNA assembly applications like making 10s – 100000s of versions of gene circuits at the same time. Finally, I introduce a collection of auxin circuit DNA parts that can be assembled interchangeably for rapid synthetic auxin engineering.

Due to the limitations of silicon (Si), there is a paradigm shift in research focusing on wide-bandgap-based (WBG) materials. SiC power semiconductors exhibit superiority in terms of switching speed, higher breakdown electric field, and high working temperature, slowly becoming a global solution in harsh medium-voltage (MV) high-power environments. However, to utilize the SiC MOSFET device to achieve those next-generation, high-density, high-efficiency power electronics converters, one must solve a plethora of challenges. For the MV SiC MOSFET device, a high-performance gate-driver (GD) is a key component required to maximize the beneficial SiC MOSFET characteristics. GD units must overcome associated challenges of electro-magnetic interference (EMI) with regards to common-mode (CM) currents and cross-talk, low driving loop inductance required for fast switching, and device short-circuit (SC) protection. Developed GDs (for 1.2 kV, and 10 kV devices) are able to sustain dv/dt higher than 100 V/ns, have less than 5 nH gate loop inductance, and SC protection, turning off the device within 1.5 us. Even with the introduction of SiC MOSFETs, power devices remain the most reliability-critical component in the converter, due to large junction temperature (Tj) fluctuations causing accelerated wear-out. Real-time (online) measurement of the Tj can help improve long-term reliability by enabling active thermal control, monitoring, and prognostics. An online Tj estimation is accomplished by generating integrated intelligence on the GD level. The developed Tj sensor exhibits a maximum error less than 5 degrees Celsius, having excellent repeatability of 1.2 degrees Celsius. Additionally, degradation monitoring and an aging compensation scheme are discussed, in order to maintain the accuracy of the sensor throughout the device's lifetime. Since ultra high-voltage SiC MOSFET devices (20 kV) are impractical, the modular multilevel converter (MMC) emerged as a prospective topology to achieve MV power conversion. If the kernal part of the power-cell (main constitutive part of the MMC converter) is an SiC MOSFET, the design is able to achieve very high-density and high-efficiency. To ensure a successful operation of the power-cell, a systematic design and assessment methodology (DAM) is explored, based on the 10 kV SiC MOSFET power-cell. It simultaneously addresses challenges of high-voltage insulation, high dv/dt and EMI, component and system protections, as well as thermal management. The developed power-cell achieved high-power density of 11.9 kW/l, with measured peak efficiency of n=99.3 %@10 kHz. It successfully operated at Vdc=6 kV, I=84 A, fsw>5 kHz, Tj<150 degrees Celsius and had high switching speeds over 100 V/ns. Lastly, to achieve high-power density and high-efficiency on the MV converter level, challenges of high-voltage insulation, high-bandwidth control, EMI, and thermal management must be solved. Novel switching cycle control (SCC) and integrated capacitor blocked-transistor (ICBT) control methodologies were developed, overcoming the drawbacks of conventional MMC control. These novel types of control enable extreme reduction in passive component size, increase the efficiency, and can operate in dc/dc, dc/ac, mode, potentially opening the modular converter to applications in which it was not previously used. In order to explore the aforementioned benefits, a modular, scalable, 2-cell per arm, prototype MV converter based on the developed power-cell is constructed. The converter successfully operated at Vdc=12 kV, I=28 A, fsw=10 kHz, with high switching speeds, exhibiting high transient immunity in both SCC and ICBT. / Doctor of Philosophy / In medium-voltage applications, such as an electric grid interface in highly populated areas, a ship dc system, a motor drive, renewable energy, etc., land and space can be very limited and expensive. This requires the attributes of high-density, high-efficiency, and reliable distribution by a power electronics converter, whose central piece is the semiconductor device. With the recent breakthrough of SiC devices, these characteristics are obtainable, due to SiC inherent superiority over conventional Si devices. However, to achieve them, several challenges must be overcome and are tackled by this dissertation. Firstly, as a key component required to maximize the beneficial SiC MOSFET characteristics, it is of utmost importance that the high-performance gate-driver be immune to interference issues caused by fast switching and be able to protect the device against a short-circuit, thus increasing the reliability of the system. Secondly, to prevent accelerated degradation of the semiconductor devices due to high-temperature fluctuations, real-time (online) measurement of the Tj is developed on the gate-driver to help improve long-term reliability. Thirdly, to achieve medium-voltage high-power density, high-efficiency modular power conversion, a converter block (power-cell) is developed that simultaneously addresses the challenges of high-voltage insulation, high interference, component and system protections, and thermal management. Lastly, a full-scale medium-voltage modular converter is developed, exploiting the advantages of the fast commutation speed and high switching frequency offered by SiC, meanwhile exhibiting exceptional power density and efficiency.

Emerging large-scale modular power converters are pursuing high-performance distributed control systems. As opposed to the centralized control architecture, the distributed control architecture features shared computational burdens, pulse-width modulation (PWM) latency compensation, simplified fiber-optic cable connection, redundant data routes, and greatly enhanced local control capabilities. Modular multilevel converters (MMCs) with conventional control are subjected to large capacitor voltage ripples, especially at low-line frequencies. It is proved that with appropriate arm current shaping in the timescale of a switching period, referred as the switching-cycle control (SCC), such line-frequency dependence can be eliminated and MMCs are enabled to work even in dc-dc mode. Yet the SCC demands multiple times of arm current alternations in one switching period. To achieve the high-bandwidth current regulation, hybrid modulation approach incorporating both the carrier-based modulation and the peak-current-mode (PCM) modulation is adopted. The combined digital and analog control and the extreme time-sensitive nature together pose great challenges on the practical implementation that the existing distributed control systems cannot cope with. This dissertation aims to develop an optimized distributed control system for SCC implementation. The critical analog PCM modulation is enabled by the intelligent gate driver with integrated rogowski coil and field programmable gate array (FPGA). A novel distributed control architecture is proposed accordingly for SCC applications where the hybrid modulation function is shifted to the gate driver. The proposed distributed control solution is verified in the SCC-based converter operations. Accompanied by the growing availability of medium-voltage silicon carbide (SiC) devices, fast-switching-enabled novel control schemes raise a high synchronization requirement for the communication network. Power electronics system network (PESNet) 3.0 is a proposed next-generation communication network designed and optimized for a distributed control system. This dissertation presents the development of PESNet 3.0 with a sub-nanosecond synchronization error (SE) and a gigabits-per-second data rate dedicated for large-scale high-frequency modular power converters. The White Rabbit Network technology, originally developed for the Large Hadron Collider accelerator chain at the European Organization for Nuclear Research (CERN), has been embedded in PESNet 3.0 and tailored to be suited for distributed power conversion systems. A simplified inter-node phase-locked loop (N2N-PLL) has been developed. Subsequently, stability analysis of the N2N-PLL is carried out with closed-loop transfer function measurement using a digital perturbation injection method. The experimental validation of the PESNet 3.0 is demonstrated at the controller level and converter level, respectively. The latter is on a 10 kV SiC-MOSFET-based modular converter prototype, verifying ±0.5 ns SE at 5 Gbps data rate for a new control scheme. The communication network has an impact on the converter control and operation. The synchronicity of the controllers has an influence on the converter harmonics and safe operation. A large synchronization error can lead to the malfunction of the converter operation. The communication latency poses a challenge to the converter control frequency and bandwidth. With the increased scale of the modular converter and control frequency, the low-latency requirement of communication network becomes more stringent. / Doctor of Philosophy / Emerging silicon carbide (SiC) power devices with 10 times higher switching frequencies than conventional Si devices have enabled high-frequency high-density medium-voltage converters. In the meantime, the power electronics building block (PEBB) concept has continually benefited the manufacturing and maintenance of modular power converters. This philosophy can be further extended from power stages to control systems, and the latter become more distributed with greatly enhanced local control capabilities. In the distributed control and communication system, each PEBB is equipped with a digital controller. In this dissertation, a real-time distributed control architecture is designed to take the advantage of the powerful processing capability from all digital control units, achieving a minimized digital delay for the control system. In addition, pulse-width modulation (PWM) signals are modulated in each PEBB controller based on its own clock. Due to the uncontrollable latency among different PEBB controllers, the synchronicity becomes a critical issue. It is necessary to ensure the synchronous operation to follow the desired modulation scheme. This dissertation presents a synchronized communication network design with sub-ns synchronization error and gigabits-per-second data rate. Finally, the impact of the communication network on the converter operation is analyzed in terms of the synchronicity, the communication latency and fault redundancy.

No / In this paper we propose a unified approach for integrating implicit and explicit knowledge in neurosymbolic systems as a combination of neural and neuro-fuzzy modules. In the developed hybrid system, training data set is used for building neuro-fuzzy modules, and represents implicit domain knowledge. The explicit domain knowledge on the other hand is represented by fuzzy rules, which are directly mapped into equivalent neural structures. The aim of this approach is to improve the abilities of modular neural structures, which are based on incomplete learning data sets, since the knowledge acquired from human experts is taken into account for adapting the general neural architecture. Three methods to combine the explicit and implicit knowledge modules are proposed. The techniques used to extract fuzzy rules from neural implicit knowledge modules are described. These techniques improve the structure and the behavior of the entire system. The proposed methodology has been applied in the field of air quality prediction with very encouraging results. These experiments show that the method is worth further investigation.

Pro bono work has always appealed to me. The prospect of being able to help those less fortunate with my knowledge and skillset is uplifting and gratifying. There is something truly rewarding about taking the architectural knowledge and training I have received and finding a solution to a problem for a nonprofit or a group of people that could not easily afford to hire someone. It gives me the opportunity to explore creative solutions with a low budget while still making something beautiful and thoughtful, that not only provides the spaces needed but also adds the detailing and uniqueness that gives the place and its users a sense of pride and pleasure. This thesis seeks to present the programmatic needs, local building materials and resources, a study in efficient building, the local needs and customs, and ways to improve people's lives with an orphanage in Savanette, Haiti. The goal is to explore the fundamental needs of an orphanage and a school in a developing country and develop strategies to address these needs. A successful orphanage needs to provide comfortable housing but also a sense of safety and security, a loving environment where orphans can grow and heal, a self-sustaining community that can care for the facility, and a means to train and educate orphans for adulthood and the working world. Since education is such a central need for an orphanage, and since schools are limited in Haiti, it only made sense to open this up to children in the surrounding area as well. The purpose of this thesis is to develop an architectural language of building components that can be utilized to answer the programmatic needs of the orphanage and school. This system creates the overall structural layout and is intended to be an easily constructible and expandable model while providing good design that is culturally sensitive. / Master of Architecture

P.L.U.G. is a prototypical solution to a highly specialized design problem that emerged in support of remote biological field research in the Mahale mountains of Western Tanzania. In collaboration with researchers from the Virginia Maryland Regional College of Veterinary Medicine's (VMRCVM) Bush to Base Bioinformatics(B2B) group a team of students and faculty from the Virginia Tech School of Architecture + Design designed, constructed, tested, and deployed the mobile field laboratory which houses up to four researchers and includes clean laboratory space, living accommodation, autonomous electricity generation, and a satellite-based communications network. P.L.U.G. consists of two primary elements, a rigid enclosed laboratory and fabric super structure that are constructed using a series of functionally-complex building components that are designed to be carried and assembled by two researchers, in one day, without the use of tools. (Kaur etal. 2007) The resulting system can be mass produced and utilized in the establishment of infrastructure in remote, environmentally sensitive, and unstable environments and has implication in disaster relief housing, human heath stations, remote research, mobile educational facilities, and any other environment or event that requires rapidly deployable, self-sufficient infrastructure. The prototype laboratory was successfully deployed during the summer of 2007 and has been field tested by the Virginia Maryland College of Veterinary Medicine (VMRCVM) Bush-2-Base Bioinformatics (B2B) research group. Currently the laboratory program exists as part of a newly developed long-term research initiative surrounding Deployable Infrastructure in Support of Science and Education (DISSed Lab) initiated by the author in response to perceived demand for such accommodation. / Master of Science

Embedded systems are so ubiquitous that they account for almost 90% of all the computing devices. They range from very small scale devices with an 8-bit microcontroller and few kilobytes of RAM to large-scale devices featuring PC-like performance with full-blown 32-bit or 64-bit processors, special-purpose acceleration hardware and several gigabytes of RAM. Each of these classes of embedded systems have unique set of challenges in terms of hardware utilization, performance and power consumption. As network connectivity becomes a standard feature in these devices, security becomes an important concern. Public Key Cryptography is an indispensable tool to implement various security features necessary on these embedded platforms. In this thesis, we provide optimized PKC solutions on platforms belonging to two extreme classes of the embedded system spectrum. First, we target high-end embedded platforms Qualcomm Snapdragon and Intel Atom. Each of these platforms features a dual-core processor, a GPU and a gigabyte of RAM. We use the SIMD coprocessor built into these processors to accelerate the modular arithmetic which accounts for the majority of execution time in Elliptic Curve Cryptography. We exploit the structure of NIST primes to perform the reduction step as we perform the multiplication. Our implementation runs over two times faster than OpenSSL implementations on the respective platforms. The second platform we targeted is an energy-harvested wireless sensor node which has a 16-bit MSP430 microcontroller and a low power RF interface. The system derives its power from a solar panel and is constrained in terms of available energy and computational power. We analyze the computation and communication energy requirements for different signature schemes, each with a different trade-off between computation and communication. We investigate the Elliptic Curve Digital Signature Algorithm (ECDSA), the Lamport-Diffie one-time hash-based signature scheme (LD-OTS) and the Winternitz one-time hash-based signature scheme (W-OTS). We demonstrate that there’s a trade-off between energy needs, security level and algorithm selection. However, when we consider the energy needs for the overall system, we show that all schemes are within one order of magnitude from each another. / Master of Science