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Knoxville, TN, United States

Hashemian H.M.,AMS Corporation
Progress in Nuclear Energy | Year: 2011

The nuclear power industry is working to reduce generation costs by adopting condition-based maintenance strategies and automating testing activities. These developments have stimulated great interest in on-line monitoring (OLM) technologies and new diagnostic and prognostic methods to anticipate, identify, and resolve equipment and process problems and ensure plant safety, efficiency, and immunity to accidents. This paper provides examples of these technologies with particular emphasis on eight key OLM applications: detecting sensing-line blockages, testing the response time of pressure transmitters, monitoring the calibration of pressure transmitters on-line, cross-calibrating temperature sensors in situ, assessing equipment condition, performing predictive maintenance of reactor internals, monitoring fluid flow, and extending the life of neutron detectors. These applications are discussed in the following sections. Emphasis is placed on the principles of a core OLM method - noise analysis - and the technical requirements for an integrated OLM system are summarized. © 2010 Elsevier Ltd. All rights reserved. Source

Hashemian H.M.,AMS Corporation
IEEE Transactions on Instrumentation and Measurement | Year: 2011

Condition-based maintenance techniques for industrial equipment and processes are described in this paper together with examples of their use and discussion of their benefits. These techniques are divided here into three categories. The first category uses signals from existing process sensors, such as resistance temperature detectors (RTDs), thermocouples, or pressure transmitters, to help verify the performance of the sensors and process-to-sensor interfaces and also to identify problems in the process. The second category depends on signals from test sensors (e.g., accelerometers) that are installed on plant equipment (e.g., rotating machinery) in order to measure such parameters as vibration amplitude. The vibration amplitude is then trended to identify the onset of degradation or failure. This second category also includes the use of wireless sensors to provide additional points for collection of data or allow plants to measure multiple parameters to cover not only vibration amplitude but also ambient temperature, pressure, humidity, etc. With each additional parameter that can be measured and correlated with equipment condition, the diagnostic capabilities of the category can increase exponentially. The first and second categories just mentioned are passive, which means that they do not involve any perturbation of the equipment or the process being monitored. In contrast, the third category is active. That is, the third category involves injecting a test signal into the equipment (sensors, cables, etc.) to measure its response and thereby diagnose its performance. For example, the response time of temperature sensors (RTDs and thermocouples) can be measured by the application of the step current signal to the sensor and analysis of the sensor response to the application of the step current. Cable anomalies can be located by a similar procedure referred to as the time domain reflectometry (TDR). This test involves a signal that is sent through the cable to the end device. Its reflection is then recorded and compared to a baseline to identify impedance changes along the cable and thereby identify and locate anomalies. Combined with measurement of cable inductance (L), capacitance (C), and loop resistance (R), or LCR testing, the TDR method can identify and locate anomalies along a cable, identify moisture in a cable or end device, and even reveal gross problems in the cable insulation material. There are also frequency domain reflectometry (FDR) methods, reverse TDR, trending of insulation resistance (IR) measurement, and other techniques which can be used in addition to or instead of TDR and LCR to provide a wide spectrum of tools for cable condition monitoring. The three categories of techniques described in this paper are the subject of current research and development projects conducted by the author and his colleagues at the AMS Corporation with funding from the U.S. Department of Energy (DOE) under the Small Business Innovation Research (SBIR) program. © 2010 IEEE. Source

AMS Corporation | Date: 2015-06-22

A drug delivery system that can be deployed from a catheter and retained within the bladder for delivery of treatment drug solutions over a period of time. The delivery system includes an inflatable or expandable delivery element that can be collapsed within the catheter tip for navigation into the bladder before being inflated or expanded within the bladder. The inflated or expanded delivery element can engage the bladder walls or sized to be too large to be passed from the bladder such that the delivery element is retained within the bladder after inflation or expansion to administer a treatment drug solution over an extended period of time.

AMS Corporation | Date: 2015-02-20

Apparatus and methods are provided for treating urinary incontinence, fecal incontinence, and other pelvic defects or dysfunctions, in both males and females, using one or more lateral implants to reinforce the supportive tissue of the urethra. The implants are configured to engage and pull (e.g., pull up) pelvic tissue to cause the lateral sub-urethral tissue, such as the endopelvic fascia, to tighten and provide slack reduction for improved support. As such, certain embodiments of the implants can be utilized to eliminate the need for mesh or other supportive structures under the urethra that is common with other incontinence slings.

AMS Corporation | Date: 2015-01-27

Described are devices and methods related to the needleless injection of fluid into tissue of the lower urinary tract, such as the urethra and prostate.

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