Knowledge of anthropometric dimensions is important for the design of workspaces and equipment. In a developing country, such as Colombia, no anthropometric survey for Colombian adults has yet been published. Therefore, the purpose of this study is to assemble a Colombian adult anthropometric data set sufficiently accurate for design applications. An anthropometric survey was conducted on 134 Colombian adults living in South Florida. Twenty body dimensions were measured. Moreover, an anthropometric estimation method was selected, described and validated to be used as a reference when measurement of the user population is not possible. Anthropometric estimates, using the scaling ratio method, and those obtained in the survey were analyzed and compared with other population data. Tables are assembled and dimensional models are suggested which may be used as a design tool.

The purpose of this research was to characterize a response surface with respect to the changes made to the input variables of an emergency room system. Response Surface Methodology (RSM) was used to identify the behavior of the response variable with respect to the changes made to the input variable. Several factors were examined for relevancy and significance for the purpose of experimentation. The findings of this research revealed that one factor (nurses) was very significant to the performance measures (time in the system). However, the interaction between the other factors also played an important role. It was determined that a linear regression is not useful in predicting the assessed value of time in the system in emergency rooms. Non-linear models need to be explored. A series of production rales were derived. These production rales can be used in a variety of situations where a decision on how to modify model inputs needs to be made.

<p> Energy has historically been of great importance to the world. Depletion of fossil fuels, growing demand, global warming, and etc. have even accentuated this importance more. Amongst the biomass for production of biofuel which is one of the most promising renewable energy options, algae have been gaining a lot of attention in recent years. This thesis will propose a Biofuel Supply Chain Network Design for the development of algal biofuels. In order to do so, a Mixed Integer Linear Program will be created to design and optimize a biofuel supply chain from raw material procurement to biofuel distribution. Furthermore, a robust optimization method will be utilized to enable the model to cope with uncertainties of the biofuel supply chain. In addition, an environmental objective would be considered alongside an economic objective both of which are optimized by augmented &egr;-Constraint method to address issues such as global warming.</p><p>

The future grid will combine both smart distribution network and distributed energy resources (DER) ensures it is reliable to do operations and increase the power quality. In the recent years, along with the traditional voltage regulators such as capacitor banks and tap changer transformers, power and voltage control based on DER method is widely proposed to cope with the overvoltage and undervoltage issues that causes by large penetration of distributed generation( DG). Moreover, with the application of advanced communication technology, some communication methods are applied on the voltage control in order to make the system coordinated. This thesis explores the area of decentralized control method to have a better understanding and knowledge of power system and its control. This is accomplished by designing a power system model and implement decentralized voltage control on it. The work starts with categorizing recent publications on coordinated voltage, summarizes way they modeled and built the systems, how they decoupled the systems and categorized the solution methods. Then this thesis proposes a novel coordinated voltage control technique designed to regulate the voltage along a distribution network by using zonal control of multiple PVs. The proposed strategy is tested using the IEEE 34 bus system in both offline and a controller hardware-in-the-loop (CHIL) real-time implementations. Data loss and communication latency scenarios are also performed with the objective of determining the overall behavior of the proposed controller. The outcome and aim of this work is expected to build real-time control models which can be applied on the real project / A Thesis submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester 2018. / October 24, 2018. / Controller Hardware-in-the-Loop(CHIL), Coordinated Voltage Control, Distribution System, PV / Includes bibliographical references. / Md Omar Faruque, Professor Directing Thesis; Simon Y. Foo, Committee Member; Sastry Pamidi, Committee Member.

Limited standard mechanical testing practises and stress-strain data are available for anisotropic human skin tissue in biaxial loading configurations to suitably represent skin in vivo. Inconsistencies in mechanical and physical properties in the literature due to numerous physiological factors have restricted development of biaxial testing equipment in laboratories to ad hoc research solutions having limited modifiability and parametric control. This project aims to develop a biaxial tensile testing device and testing platform which can be used in a research laboratory setting to provide a springboard to expediate mechanical skin tissue testing. The device can be easily reconfigured to accommodate a range of bulge pressures, while being driven via a 10bar compressed air supply. Based on simplified modelling of skin as an elastomer, mechanical and pneumatic resistivecapacitive pressure vessel models are developed. These are used respectively to initially specify a modifiable piston-cylinder bulge testing apparatus, and to design a customisable discrete proportional-integral closed-loop feedback pressurisation rate control system and software control environment. Pressure-time histories were successfully collected and stored on a dedicated computer for silicone sheet samples of 50mm diameter, as a surrogate for skin, that were tested using the platform to maximum pressures of about 200 kPa, at rates set between 2 20 kPa/s. The efficacy of the rate control system was affected by resolution of discrete pressurisation components that were used. The described platform is currently suitable for controlled and measured bulge pressurisation of elastomers. It is recommended to extend facility of the current platform by integrating 3D imaging and measurement technologies, to evaluate deformation of bulged anisotropic skin tissue and map inhomogeneous stress-strain fields for complex tensile stress-strain evaluations.

Since the discovery of carbon nanotubes in the early 1990s, a new era in nanotechnology opened up, impacting both scientific and technological fronts. One of the key challenges in processing of carbon nanotube-based materials and structures is proper dispersion of the nanoconstituents. Fundamental roadblocks to maximumize utilization of the exceptional properties of carbon nanotubes are their tendency to aggregate due to intermolecular forces and the resulting difficulties in dispersing them into individual tubes. In this study, a novel carbon nanotube dispersion technology that uses electrospraying was developed, analyzed, and evaluated. We established image analysis based measurement that can be used to quantify the degree and uniformity of carbon nanotube dispersion, and performed a series of designed experiments. Rigorous statistical analyses were conducted to investigate the parametric effect of electrospraying, and the design of experiments based models were derived. As validated through experiments, the design of experiments models can serve as effective guidelines for selecting the electrospraying parameters that allow controlled nanoparticle dispersion. Carbon nanotube electrospraying is expected to be applicable to a broad range of technical fields, owing to its low cost, ease of implementation, environmental friendliness, and scalability for industry use. Potential applications include, transparent, conductive carbon nanotube coating for flexible displays, multiscale carbon nanotube patterning, and continuous nanocomposite processing, the proofs-of-concept of which have been demonstrated in this study. / A Thesis submitted to the Department of Industrial and Manufacturing Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester, 2007. / September 25, 2007. / Dispersion, Electrospraying, CNT / Includes bibliographical references. / Chuck Zhang, Professor Co-Directing Thesis; Young-Bin Park, Professor Co-Directing Thesis; Zhiyong Liang, Committee Member; Joseph J. Pignatiello, Jr., Committee Member.

The distributed renewable energy generation and utilization are constantly growing, and are expected to be integrated with the conventional grid. The growing pressure for innovative solutions will demand power electronics to take an even larger role in future electric energy delivery and management systems, since power electronics are required for the conversion and control of electric energy by most dispersed generation systems Furthermore, power electronics systems can provide additional intelligent energy management, grid stability and power quality capabilities. Medium-voltage isolated dc-dc converter will become one of the key interfaces for grid components with moderate power ratings. To address the demand of medium voltage (MV) and high power capability for future electric energy delivery and management systems, the power electronics community and industry have been reacting in two different ways: developing semiconductor technology or directly connecting devices in series/parallel to reach higher nominal voltages and currents while maintaining conventional converter topologies; and by developing new converter topologies with traditional semiconductor technology, known as multilevel converters or modular converters. The modular approach uses the well-known, mature, and cheaper power semiconductor devices by adopting new converter topologies. The main advantages of the modular approach include: significant improvement in reliability by introducing desired level of redundancy; standardization of components leading to reduction in manufacturing cost and time; power systems can be easily reconfigured to support varying input-output specifications; and possibly higher efficiency and power density of the overall system. Input-series output-parallel (ISOP) modular configuration is a good choice to realize MV to low voltage (LV) conversion for utility application. However, challenges still remain. First of all, for the high-frequency MV utility application, the low switching loss and conduction loss are must-haves for high efficiency, while bidirectional power flow capability is a must for power management requirement. To address the demand, the phase-shift dual-half-bridge (DHB) is proposed as the constituent module of ISOP configuration for MV application. The proposed ISOP DHB converter employs zero-voltage-switching (ZVS) technique combined with LV MOSFETs to achieve low switching and conduction losses under high frequency operation, and therefore high efficiency and high power density, and bidirectional power flow as well. Secondly, a large load range of high efficiency is desired rather than only a specific load point due to the continuous operation and large load variation range of utility application, which is of high importance because of the rising energy cost. This work proposes a novel DHB converter with an adaptive commutation inductor. By utilizing an adaptive inductor as the main energy transfer element, the output power can be controlled by not only the phase shift but also the commutation inductance, which allows the circulating energy to be optimized for different load conditions to maintain ZVS under light load conditions and minimize additional conduction losses under heavy load conditions as well. As a result, the efficiency at both light and heavy load can be significantly improved compared with the conventional DHB converter, and therefore extended high-efficiency range can be achieved. In addition, current stress of switch devices can be reduced. The theoretical analysis is presented and validated by the experimental results on a 50 kHz, 1 kW dc-dc converter module. Thirdly, input-voltage sharing and output-current sharing are critical to assure the advantages of the ISOP modular configuration. To solve this issue, an identically distributed control scheme is proposed in this work. The proposed control scheme, using only one distributed voltage loop to realize both input-voltage and output-current sharing, provides plug-and-play capability, possible high-level fault tolerance, and easy implementation. Another unique advantage of the proposed ISOP DHB converter is the power rating can be easily extended further by directly connecting multiple ISOP DHB converters in input-parallel-out-parallel (IPOP) while no additional control is needed. The proposed control scheme is elaborated using the large-signal average model. Further, the stability of the control schemes is analyzed in terms of the constituent modules' topology as well as the configuration, and then an important fact that the stability of control scheme depends on not only the configuration but also the constituent module topology is first revealed in this work. Finally, the simulation and experimental results of an ISOP DHB converter consisting of three modules are presented to verify the proposed control scheme and the high frequency high efficiency operation. / A Dissertation submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2011. / June 6, 2011. / Adaptive Inductor, Circulating Energy, Current Sharing, Isolated Bidirectional DC-DC Converter, High Frequency Transformer, Dual Half Bridge, Input-Series-Output-Parallel, Phase-Shift Control, Medium Voltage Driect Current, Voltage Sharing, Solid State Transformer, Zero Voltage Switching / Includes bibliographical references. / Hui Li, Professor Directing Dissertation; Emmanuel G. Collins, Jr., University Representative; Chris S. Edrington, Committee Member; Jim P. Zheng, Committee Member; Petru Andrei, Committee Member.

There is a plethora of interesting science and many applications that rely on wrinkling in thin sheets. Though wrinkling may not be appreciated in some instances, in many other situations wrinkles can help to comprehend various physical phenomena. This work reports on the development of materials that can induce surface roughness through the creation of wrinkled surfaces. The textured surfaces are engineered through a bilayer system consisting of poly(dimethylsiloxane) and a modified surface layer. This research sought to study and understand methodologies for the controlled formation of wrinkles on surfaces of structures. The creation of wrinkled surfaces was explored in metal deposited thin films atop PDMS. A series of experiments were designed to investigate the significant material parameters that effect low deformation wrinkling mechanics. In doing so, the experimental bilayer system successfully validated an empirical model. Building upon the understanding of key material parameters that affect low deformation wrinkling, oxidized PDMS was used to extend this knowledge in mechanically perturbed-induced wrinkling. A model was constructed that describes the wrinkle profile in terms of the paramount process parameters of plasma treatment. This feature enables integration of micro/nano-wrinkle manufacturing on large-scales. Finally, wrinkle morphology was controlled in a series of wrinkle patterning experiments. Transformations of various wrinkle patterns was achieved by coordinating the amount/direction of strain exerted on the system and exploiting the strain release process, and also by manipulating the geometric properties. The versatility of wrinkle patterning techniques demonstrates further advances in surface roughness engineering. The impact of this work is aimed at enhancing aerodynamic technologies and capabilities. This study demonstrated that by modifying the PDMS surface to create bilayer systems, the wavelength, amplitude, and surface roughness of the wrinkled films can be effectively controlled. / A Thesis submitted to the Department of Industrial and Manufacturing Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2015. / July 20, 2015. / Includes bibliographical references. / Okenwa Okoli, Professor Directing Thesis; Tarik Dickens, Committee Member; Zhibin Yu, Committee Member.

It is desirable to use nanostructured composites to produce high-strength, high-conductive materials for magnet development. In this research, severe plastic deformation (e ≥ 2.0) is used to produce nanostructured Cu-Ag composites in an off-eutectic (Cu-16at%Ag) and an eutectic (Cu-60at%Ag) composite. These two compositions are chosen in order to obtain a better understanding of the off-eutectic microstructure which is comprised of both proeutectic and eutectic regions. The mechanical and conductive properties of Cu-Ag material make it ideal for use in magnetic applications. The scanning electron microscopy images demonstrate that the as-cast off-eutectic material has large proeutectic Cu-rich dendrite embedded within nano-sized lamellar eutectic Cu + Ag. On the other hand, the eutectic material has a homogeneous distribution of alternating nano-sized Cu + Ag lamellae. The evolution of the microstructure and mechanical properties is dependent on the processing method and the composition of the materials. Both drawing and rolling processes resulted in an increase in mechanical strength, Vickers hardness, electrical resistivity, texture strengthening, alignment and refinement of the Cu-Ag lamellae in both materials. The enhancement of the mechanical strength and hardness is attributed to the alignment and texturing in the nanostructured fiber composites. The fabrication methods, flux-melt-casting (EF), flux-melt-casting + Equal Channel Angular Extrusion (ECAE to e = 2.0) (EF_E), and flux-melt-directional-solidification (EFS) produces lamellae thicknesses of 210+/-33 nm, 199+/-36 nm, and 161+/-21 nm, respectively. In spite of an initial ECAE (e= 2.0), the lamella refinement in the material processed by flux-melt + ECAE + swaged + drawn (total e = 4.6) is 73+/-12 nm and comparable to the 84+/-12 nm obtained in the flux-melt + swaged + drawn (total e = 2.6) material. The incorporation of directional solidification (DS) + swaged + drawn further reduces the lamella thickness to 59+/-13 nm (total e = 2.6). This suggests that the initial ECAE has a minimal effect on the reduction in the lamella thickness. Typical fcc <111> + <100> duplex texture is produced in the axis-symmetric swaging + drawing deformation in both the Cu and Ag phases. The off-eutectic Ag and Cu phases wire texture intensities are 27% and 76% higher than the eutectic. The texture in both rolled Cu-Ag composites are Brass {110}<-112>+ a weak S1{124}<21-1> and S2{123}<41-2> components. At e ~ 4.5 the Ag and Cu phases of the off-eutectic composite has 13% and 48% stronger Brass intensity than the eutectic, respectively. In spite of the very high Cu content in the off-eutectic Cu-Ag composite, the texture of the rolled composite is Brass, even in the Cu phase. This suggests that the deformation in the composite is dominated by the mechanism of the deformation in the Ag. At large strains, the lamellae alignment in the rolling (L-S) direction is displaced due to the formation of shear bands. Both texture and shear bands results in anisotropy of the mechanical strength and electrical conductivity. Molecular Dynamics (MD) is used to provide a better understanding of the deformation mechanisms during rolling and wire drawing of the Cu-Ag nanocomposites. This is simulated using uniaxial tension, compression, and nano-indentation of the nanocomposites' bilayers. Initial relaxation of the Cu-Ag bilayers reveals the formation of a semi-coherent Cu/Ag interface which later serves as both the source for nucleation of partial dislocations and a barrier to the moving dislocations. The MD results suggest that the deformation in the Cu-Ag bilayer system occurs in four stages: (1) elastic deformation up to extremely high stresses, (2) nucleation of the leading partial dislocations from the interface on multiple slip systems, (3) propagation of the partial dislocations which leads to the formation of stacking faults, (4) the formation of multiple dislocation loops and stacking fault systems which propagate and expand into the material at much lower stress values. Eventually, the influence of large dislocation densities and interface effects dominates the materials and the stress in the system begins to increase slightly, a trait of possible strain-hardening. The leading partial dislocations nucleate first in the Ag layer for the proeutectic material on the {111} plane in the <112> directions for both tension and compression simulations. This may explain why the dominant texture that is observed in the off-eutectic material is Brass, even in the proeutectic Cu-rich regions. The simulated [111] nano-hardness result is 378 HV and 384 HV which is higher than the measured nano-hardness of 267 and 288 for eutectic and off-eutectic drawn wires, respectively. The [111] simulated stress-strain curves show much higher value of yield stress (~8 GPa) than the experimental result (~0.9 GPa). / A Dissertation submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester, 2010. / October 18, 2010. / Cu-Ag, Nanostructured, Eutectic, Off-eutectic, Molecular Dynamics, Lamella / Includes bibliographical references. / Peter N. Kalu, Professor Co-Directing Dissertation; Ke Han, Professor Co-Directing Dissertation; Okenwa Okoli, University Representative; William S. Oates, Committee Member; Farrukh S. Alvi, Committee Member; Anthony D. Rollett, Committee Member.

Being the interface between Energy Storage Element (ESE) and DC bus in Fuel Cell Vehicle (FCV), the high power density bidirectional dc-dc converter is an essential component of the energy management system. In this dissertation, two novel multiphase bidirectional dc-dc converters featuring high power density for FCV application are proposed. Also in this dissertation, the averaged models of the proposed three-phase bidirectional DC-DC converters are developed. In order to study the bidirectional dc-dc converter interfacing with ESE to supply and absorb the electric energy in the FCV system, both the Controller Hardware-In-the-Loop (CHIL) method and Power Hardware-In-the-Loop (PHIL) method are proposed and applied. Phase I is a pure software simulation of the original FCV system. In this phase, the bidirectional dc-dc converter and all other FCV power train components are modeled and simulated on Real Time Digital Simulator (RTDS). As a result of the fast computation through distributed parallel processing of the RTDS, the simulation can provide an accurate enough reference for the following phases. Phase II includes a controller in the simulation loop. The bidirectional dc-dc converter controller is implemented with a real hardware Digital Signal Processor (DSP), which replaces the simulated control system. This Controller Hardware-In-the-Loop increases the realism of the simulation and eliminates the unpredictable error from modeling the controller. The results from the initial phases can be utilized in the Phase III, where the actual hardware bidirectional dc-dc converter prototype is then interfaced with the ESE using Power Hardware-In-the-Loop. The main challenge of this PHIL is the requirement for a highly dynamic bidirectional Simulation-Stimulation (Sim-Stim) interface. This dissertation describes three different interface algorithms (Current-Voltage amplification, Voltage-Current amplification and Voltage-Voltage amplification). The closed-loop stability of the resulting PHIL system is then analyzed in terms of time delay and sampling rate. A prototype of the bidirectional Sim-Stim interface is designed and implemented in hardware to study the bidirectional dc-dc converter interfacing with ESE for FCV using PHIL. The results demonstrate the effectiveness of this approach. / A Dissertation submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester, 2010. / September 9, 2010. / Energy Storage, Bidirectional DC-DC Converter, Fuel Cell Vehicle, Power Hardware-In-the-Loop, Controller Hardware-In-the-Loop / Includes bibliographical references. / Simon Foo, Professor Directing Dissertation; Hui Li, Professor Co-Directing Dissertation; Mei Zhang, University Representative; Ming Yu, Committee Member; Chris Edrington, Committee Member.