Abstract: Pulse width modulation is provided for controlling a resonant power converter, particularly for dimming of light emitting diode arrays without loss of efficiency. Dynamic oscillation due to the beginning of a pulse width modulated pulse burst is limited by shortening of the first and/or last pulse of a pulse bust such that the first pulse of a subsequent pulse burst close to or to connect with a full load steady-state voltage/current trajectory of the power converter. Pulse shortening made be made substantially exact to virtually eliminate dynamic oscillation but substantial reduction in dynamic oscillation is provided if inexact or even performed randomly.

Abstract: By setting switching instants of a switching circuit of a resonant power converter based on current in a resonant circuit reaching a current limit of a current limitation band, soft start-up of the power converter can be achieved to avoid or limit electrical stress with full control over a trade-off between time required to settle to a full load steady-state mode of operation and the amount of electrical stress permitted while soft start up switching frequency is automatically optimized.

Abstract: Approximately one-half of the loss of delivered power from a solar panel having photovoltaic (PV) cells connected in series to form sub-panels due to shading is recovered at low hardware cost by connecting sub-panels in series and providing maximum power point tracking control in common for the series connected sub-panels such that the respective sub-panels produce equal voltages even in the presence of shading of a portion of one or more sub-panels. By doing so, the input voltage of respective power converters which control the voltage at which each sub-panel is operated can be placed close to the maximum power point of each sub-panel regardless of shading and maximum total power harvested even though the respective sub-panels are not operated at optimum voltages.

Abstract: Peak current, valley current or average current mode controlled power converters in either digital or analog implementations obtain a stabilized feedback loop and allow high system bandwidth design by use of an external ramp generator using a slope computation equation or design parameters based on fixing the quality factor of a double pole at one-half of the switching frequency at a desired value The slope of the external ramp waveform is tuned automatically with knowledge of the slope change in the waveform of inductor current of a power converter derived by differentiating a waveform in the current feedback loop. This autotuning of the external ramp generator provides immunity of quality factor change under variations of duty cycle, component values of topological change of the power converter.

Abstract: Switches of a switching circuit used to control operation of an electric motor such as in an electrically powered vehicle connect respective windings of the electric motor as a single phase inductor during battery charging. The inductor can then store inherent low frequency, second order ripple power and return that power to a load presented by a battery during battery charging to deliver substantially constant current. Storage of ripple power in the inductor allows the capacitance value, size, weight and cost of a filter capacitor of a power factor correction circuit providing input power to a battery charger to be reduced by an order of magnitude or more. Direction of current flow through the inductor is periodically reversed to avoid magnetizing the motor.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: The present invention relates to the field of medical imaging. More particularly, embodiments of the invention relate to methods, systems, and devices for imaging, including for tomography-based applications. Embodiments of the invention include, for example, a computed tomography based imaging system comprising: (a) at least one wide-beam gray-scale imaging chain capable of performing a global scan of an object and acquiring projection data relating to the object; (b) at least one narrow-beam true-color imaging chain capable of performing a spectral interior scan of a region of interest (ROI) of and acquiring projection data relating to the object; (c) a processing module operably configured for: (1) receiving the projection data; (2) reconstructing the ROI into an image by analyzing the data with a color interior tomography algorithm, aided by an individualized gray-scale reconstruction of an entire field of view (FOV), including the ROI; and (d) a processor for executing the processing module.

Abstract: Electrically conducting vanadium arsenate or vanadium phosphate materials are described. The materials include a vanadium arsenate or vanadium phosphate framework structure about organic template and water molecules which may be removed to leave a microporous structure. The three-dimensional vanadium framework may provide electronic conductivity, while the extra-framework constituents may provide ionic conductivity.

Abstract: Providing a fast current sensor direct feedback path to a modulator for controlling switching of a switched power converter in addition to an integrating feedback path which monitors average current for control of a modulator provides fast dynamic response consistent with system stability and average current mode control. Feedback of output voltage for voltage regulation can be combined with current information in the integrating feedback path to limit bandwidth of the voltage feedback signal.

Abstract: Operation of a switching power converter having an output capacitor having a small equivalent series resistance (ESR) is stabilized and jitter reduced by sensing capacitor current with gain and combining the resulting signal with the output voltage signal to provide a feedback signal to control switching of the power converter. capacitor current can be sensed without interfering with operation of the filter capacitor by providing a branch circuit having a time constant matched to the output or filter capacitor but an arbitrarily high impedance so as to be effectively lossless. The gain provided in the capacitor current signal can be tuned to provide optimally short settling time after load transients; generally within one switching cycle. Matching of time constants and/or tuning of gain can be performed automatically.

Abstract: A textured PMN-PZT ceramic is created using templated grain growth to align seed crystals in a ceramic matrix powder by tape-casting process. Heat treatment then results in the nucleation and growth of matrix crystals on aligned templates. The resulting textured PMN-PZT ceramic has high longitudinal piezoelectric coefficient and a high piezoelectric voltage coefficient. In another embodiment, a textured PMN-PT ceramic has a volume fraction of the templates no greater than 1%. The utility of this invention includes both its exceptional piezoelectric properties as well as the utilization of an economical manufacturing process that is widely used in the multi-layer ceramic capacitor industry.

Abstract: A resistive floating electrode device (RFED) provides a logic cell or non-volatile storage or dynamic or static random access memory on an extremely compact matrix with individual cells scalable to the minimum available lithographic feature size regime by providing atomic switches connected in anti-parallel relationship, preferably with a common inert electrode. Programming is facilitated by limiting current to a compliance current level in order to maintain an OB state from which the cell can be written to either the 0 or 1 state. A perfecting feature of the invention provides for selective operation of a cell as a diode or in a volatile or non-volatile storage mode within the same memory array. A series connection of three or more RFEDs in accordance with the invention having different ON state currents, OFF state currents and reset currents can be used as adaptive, neural or chaotic logic cells.

Abstract: An apparatus imparts motion to a test object such as a motor vehicle in a controlled fashion. A base has mounted on it a linear electromagnetic motor having a first end and a second end, the first end being connected to the base. A pneumatic cylinder and piston combination have a first end and a second end, the first end connected to the base so that the pneumatic cylinder and piston combination is generally parallel with the linear electromagnetic motor. The second ends of the linear electromagnetic motor and pneumatic cylinder and piston combination being commonly linked to a mount for the test object. A control system for the linear electromagnetic motor and pneumatic cylinder and piston combination drives the pneumatic cylinder and piston combination to support a substantial static load of the test object and the linear electromagnetic motor to impart controlled motion to the test object.

Abstract: The present invention relates to the fields of chemistry and pharmaceuticals. Embodiments of the present invention provide transition metal complexes of amino acids. Transition metal complexes of embodiments of the invention according to Categories I, II, III, and/or IV may be used as antimicrobial, anti-malarial, and anti-cancer agents, as well as catalysts in chemical reactions. Such compounds of the invention are particularly useful for combating multi-drug resistance against a broad range of microbials (such as MRSA and mycobacteria), including gram positive and gram negative bacteria, as well as can be used as anti-cancer agents against bladder cancer, breast cancer, colon cancer, rectal cancer, endometrial cancer, kidney cancer, leukemia, lung cancer, melanoma, non-Hodgkin's lymphoma, pancreatic cancer, prostate cancer, and thyroid cancer, to name a few.

Abstract: A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

Abstract: A phase detector for a phase-locked loop includes a phase detector that is configured to become unstable, oscillate and drift rapidly in frequency in a predictable manner when a reference frequency signal is not available. When applied, for example, to a power converter connected to a power distribution grid, the predictable oscillatory and rapid frequency drift behavior when the phase detector is unstable allows very rapid and reliable detection of disconnection from the grid, referred to as islanding.

Abstract: Core loss in an inductor is measured with reduced sensitivity to phase measurement error by connecting a reactive component to resonate with the inductor and thus cancel a portion of the reactive voltage on the inductor; reducing the phase difference between the inductor voltage and current and making the observed power more resistive. The reactive component may be a capacitor for sinusoidal excitation or an inductance such as an air core transformer for arbitrary excitation.

Abstract: A new current loop control system method is proposed for a single-phase grid-tie power conditioning system that can be used under a standalone or a grid-tie mode. This type of inverter utilizes an inductor-capacitor-inductor (LCL) filter as the interface in between inverter and the utility grid. The first set of inductor-capacitor (LC) can be used in the standalone mode, and the complete LCL can be used for the grid-tie mode. A new admittance compensation technique is proposed for the controller design to avoid low stability margin while maintaining sufficient gain at the fundamental frequency. The proposed current loop controller system and admittance compensation technique have been simulated and tested. Simulation results indicate that without the admittance path compensation, the current loop controller output duty cycle is largely offset by an undesired admittance path. At the initial simulation cycle, the power flow may be erratically fed back to the inverter causing catastrophic failure.

Abstract: The present invention provides methods, devices, and systems for in vivo treatment of cell proliferative disorders. The invention can be used to treat solid tumors, such as brain tumors. The methods rely on non-thermal irreversible electroporation (IRE) to cause cell death in treated tumors. In embodiments, the methods comprise the use of high aspect ratio nanoparticles with or without modified surface chemistry.

Abstract: The disclosure provides methods and systems for assessing microsatellites, for identifying informative microsatellite loci, and for using microsatellite data. Microsatellite information has numerous uses including, for example, to characterize disease risk, to predict responsiveness to therapy, and to non-invasively diagnose subjects.