With higher frequencies now being used in RFID systems, antennas are becoming much smaller resulting in more space on tags that can be used for innovative array designs to harvest more wireless energy. This master's thesis outlines and details a new methodology for designing and simulating the staggered pattern charge collector, a technique to improve harvesting wireless energy. Staggered pattern charge collectors enable RFID tag's to produce a higher DC voltage from a charge pump circuit by creatively using multiple arrays to increase the antenna power conversion gain without limiting the half power beamwidth. This thesis discusses the basics of patch antennas and charge pumps as well as an optimization technique for the staggered pattern array by maximizing integrated power conversion gain (IPCG). An example of a staggered pattern charge collector is fully specified from design through simulation, in preparation for fabrication. This methodology allows for the staggered pattern charge collectors to be designed, simulated, and fabricated quickly and effectively.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2009. / Includes bibliographical references.

The atomic force microscope (AFM) provides a powerful instrument for investigating and manipulating biological samples down to the subnanometer scale. In contrast to other microscopy methods, AFM does not require labeling, staining, nor fixation of samples and allows the specimen to be fully hydrated in buffer solution during the experiments. Moreover, AFM clearly compares in resolution to other techniques. In general, the AFM can be operated in an imaging or a force spectroscopy mode. In the present work, advantage was taken of this versatility to investigate single biomolecules and biomolecular assemblies. A novel approach to investigate the visco-elastic behavior of biomolecules under force was established, using dextran as an example. While a molecule tethered between a solid support and the cantilever tip was stretched at a constant velocity, the thermally driven oscillation of the cantilever was recorded. Analysis of the cantilever Brownian noise provided information about the visco-elastic properties of dextran that corresponded well to parameters obtained by alternative methods. However, the approach presented here was easier to implement and less time-consuming than previously used methods. A computer controlled force-clamp system was set up, circumventing the need for custom built analogue electronics. A commercial PicoForce AFM was extended by two computers which hosted data acquisition hardware. While the first computer recorded data, the second computer drove the AFM bypassing the manufacturer's microscope control software. To do so, a software-based proportional-integral-differential (PID) controller was implemented on the second computer. It allowed the force applied to a molecule to be held constant over time. After tuning of the PID controller, response times obtained using that force-clamp setup were comparable to those of the recently reported analogue systems. The performance of the setup was demonstrated by force-clamp unfolding of a pentameric Ig25 construct and the membrane protein NhaA. In the latter case, short-lived unfolding intermediates that were populated for less than 10 ms, could be revealed. Conventional single-molecule dynamic force spectroscopy was used to unfold the serine:threonine antiporter SteT from Bacillus subtilis, an integral membrane protein. Unfolding force patterns revealed the unfolding barriers stabilizing structural segments of SteT. Ligand binding did not induce new unfolding barriers suggesting that weak interactions with multiple structural segments were involved. In contrast, ligand binding caused changes in the energy landscape of all structural segments, thus turning the protein from a brittle, rigid into a more stable, structurally flexible conformation. Functionally, rigidity in the ligand-free state was thought to facilitate specific ligand binding, while flexibility and increased stability were required for conformational changes associated with substrate translocation. These results support the working model for transmembrane transport proteins that provide alternate access of the binding site to either face of the membrane. Finally, high-resolution imaging was exploited to visualize the extracellular surface of Cx26 gap junction hemichannels (connexons). AFM topographs reveal pH-dependent structural changes of the extracellular connexon surface in presence of HEPES, an aminosulfonate compound. At low pH (< 6.5), connexons showed a narrow and shallow channel entrance, which represented the closed pore. Increasing pH values resulted in a gradual opening of the pore, which was reflected by increasing channel entrance widths and depths. At pH > 7.6 the pore was fully opened and the pore diameter and depth did not increase further. Importantly, coinciding with pore gating a slight rotation of the subunits was observed. In the absence of aminosulfonate compounds, such as HEPES, acidification did not affect pore diameters and depths, retaining the open state. Thus, the intracellular concentration of taurine, a naturally abundant aminosulfonate compound, might be used to tune gap junction sensitivity at low pH.

Humic acids and humates are principal components of humic substances major organic constituents of soil, peat, coal and water around the world. I was involved in research into molecular dynamics simulations of interactions of quartz surfaces with aqueous solutions of ions and small organic molecules representing basic building blocks of larger biomolecules and functional groups of organic matter. We studied interactions of molecules with surfaces for a set of surface charge densities corresponding to the experimentally or environmentally relevant ranges of pH values employing molecular mechanics, molecular dynamics and ab initio techniques. Simulated quartz surfaces covered the range of surface charge densities 0.00, -0.03, -0.06 and -0.12 C-m-2, approximately corresponding to pH values 4.5, 7.5, 9.5 and 11. As model molecules, benzoic acid, phenol, o-salicylic acid and their conjugated bases were chosen. My task was to prepare topologies and parametric models of selected organic matter basic building blocks organic molecules. I focused on studying interactions of these molecules in an aqueous environment with mineral surface quartz. The aim was to process simulation results and analyse conformations of the adsorption complexes and their thermodynamic properties such as interaction energies, free energies and adsorption geometries.

Indiana University-Purdue University Indianapolis (IUPUI) / Instrument assisted soft tissue mobilization (IASTM) is a form of massage using rigid manufactured or cast devices. The delivered force, which is a critical parameter in massage during IASTM, has not been measured or standardized for most clinical practices. In addition to the force, the angle of treatment and frequency play an important role during IASTM. As a result, there is a strong need to characterize the delivered force to a patient, angle of treatment, and stroke frequency. This thesis proposes two novel mechatronic designs for a specific instrument from Graston Technique(Model GT3), which is a frequently used tool to clinically deliver localize pressure to the soft tissue. The first design is based on compression load cells, where 4-load cells are used to measure the force components in three-dimensional space. The second design uses a 3D load cell, which can measure all three force components force simultaneously. Both designs are implemented with IMUduino microcontroller chips which can also measure tool orientation angles and provide computed stroke frequency. Both designs, which were created using Creo CAD platform, were also analyzed thorough strength and integrity using the finite element analysis package ANSYS. Once the static analysis was completed, a dynamic model was created for the first design to simulate IASTM practice using the GT-3 tool. The deformation and stress on skin were measured after applying force with the GT-3 tool. Additionally, the relationship between skin stress and the load cell measurements has been investigated. The second design of the mechatronic IASTM tool was validated for force measurements using an electronic plate scale that provided the baseline force values to compare with the applied force values measured by the tool. The load cell measurements and the scale readings were found to be in agreement within the expected degree of accuracy. The stroke frequency was computed using the force data and determining the peaks during force application. The orientation angles were obtained from the built-in sensors in the microchip.