Design and Simulation of Nonlinear Control Strategies for Heaving Point Wave Energy Converters in WEC-Sim

As the sources of our electricity shift from centralized and carbon emitting, to a portfolio of distributed, clean-energy sources, the wave energy converter (WEC) has become a topic of exploration and development for providing coastal communities electric power. Part of this trend has included an effort to create open source WEC modeling and simulation software. The Wave Energy Converter Simulator (WEC-Sim) provides a software solution for designing and simulating the various aspects related to wave energy, using linear wave theory and control strategies. This thesis represents a continuation of that effort and a contribution to WEC-Sim, demonstrating the use of nonlinear control strategies on wave energy converters. A fuzzy logic controller is designed and implemented in WEC-Sim, as well as a generally nonlinear control strategy for power-take-off (PTO) force. The nonlinear control models are intended for incorporation into WEC-Sim, as tutorials to provide WEC researchers an introduction to nonlinear control methods

Amtrak: Budget and Reauthorization

Amtrak was created by Congress in 1970 to provide intercity passenger railroad service. Without a yearly federal grant to cover operating losses, Amtrak would not survive as presently configured. This issue brief discusses reform proposals from both the Administration and Amtrak in the 109th Congress. It addresses the appropriations requested by Amtrak, the reluctance of the Administration to provide aid, and its willingness to let Amtrak enter bankruptcy, resulting in restructuring and reform of inefficient operations

Nitinol 60 as a Material For Spacecraft Triboelements

The mechanical properties of Nitinol 60, 60 w/o Ni, 40 w/oTi (55 a/o Ni, 45 a/o Ti) are sufficiently attractive to warrant its consideration as a lubricated spacecraft triboelement. The ability to lubricate Nitinol 60 by the oils usually used on spacecraft mechanisms--Pennzane 2001A, Krytox 143AC and Castrol 815Z - was experimentally determined. These oils were run in the boundary lubrication regime for Nitinol 60 balls running against a 440C steel counterface in the vacuum spiral orbit tribometer. Test results consisting of the coefficient of friction versus time (friction traces) and relative degradation rates are presented. Contrary to the inability to successfully lubricate other metal alloys with high titanium content, it was found that Nitinol 60 is able to be lubricated by these oils. Overall, the results presented here indicate that Nitinol 60 is a credible candidate material for spacecraft bearing applications

Xurography actuated valving for arbitrary timing of centrifugal flow control in parallelized multi-step bioassays

Here we introduce a new, instrument controlled valving scheme for the centrifugal platform which is based upon dissolvable film (DF) technology. Liquid, restrained at any point upon the disc, is prevented from wetting a DF via a trapped gas pocket. From this pocket a pneumatic channel runs to a sealed vent located on the top surface of the disc. Controlled scouring of this seal by a robotic knifecutter permits venting of the trapped gas, and thus actuation of the valve. To demonstrate the potential of these valves, we present a disc developed towards a biplex liver assay panel

A review of oxyhalide disinfection by-products determination in water by ion chromatography and ion chromatography-mass spectrometry

This paper is a review of ion chromatographic (IC) separations of inorganic oxyhalide disinfection by-products (DBPs) in water and beverages. The review outlines the chemical mechanisms of formation, regulation of maximum allowable levels, chromatographic column selection and speciation. In addition, this review highlights the application of IC coupled to mass spectrometry (MS) for trace and elemental composition analysis of oxyhalides, along with the analytical considerations associated to enable sensitive analysis. Furthermore, a review of literature concerning IC determination of inorganic oxyhalide DBPs in environmental matrices, including water, published since 2005 is presented, with a focus on MS detection, and a discussion on the relative performance of the methods. Finally some prospective areas for future research, including fast, selective, multi-analyte analysis, for this application are highlighted and discussed

COMPULS:Design of a multicenter phenotypic, cognitive, genetic, and magnetic resonance imaging study in children with compulsive syndromes

Background: Compulsivity, the closely linked trait impulsivity and addictive behaviour are associated with several neurodevelopmental disorders, including attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and obsessive compulsive disorder (OCD). All three disorders show impaired fronto-striatal functioning, which may be related to altered glutamatergic signalling. Genetic factors are also thought to play an important role in the aetiology of compulsivity-related disorders. Methods: The COMPULS study is a multi-center study designed to investigate the relationship between the traits compulsivity, impulsivity, and, to a lesser extent, addictive behaviour within and across the neurodevelopmental disorders ADHD, ASD, and OCD. This will be done at the phenotypic, cognitive, neural, and genetic level. In total, 240 participants will take part in COMPULS across four different sites in Europe. Data collection will include diagnostic interviews, behavioural questionnaires, cognitive measures, structural, functional and spectral neuroimaging, and genome-wide genetic information. Discussion: The COMPULS study will offer the unique opportunity to investigate several key aspects of compulsivity across a large cohort of ADHD, ASD and OCD patients

Application of programmable bio-nano-chip system for the quantitative detection of drugs of abuse in oral fluids

Objective: There is currently a gap in on-site drug of abuse monitoring. Current detection methods involve invasive sampling of blood and urine specimens, or collection of oral fluid, followed by qualitative screening tests using immunochromatographic cartridges. While remote laboratories then may provide confirmation and quantitative assessment of a presumptive positive, this instrumentation is expensive and decoupled from the initial sampling making the current drug-screening program inefficient and costly. The authors applied a noninvasive oral fluid sampling approach integrated with the in-development chip-based Programmable bio-nano-chip (p-BNC) platform for the detection of drugs of abuse. Method: The p-BNC assay methodology was applied for the detection of tetrahydrocannabinol, morphine, amphetamine, methamphetamine, cocaine, methadone and benzodiazepines, initially using spiked buffered samples and, ultimately, using oral fluid specimen collected from consented volunteers. Results: Rapid (∼10 min), sensitive detection (∼ng/mL) and quantitation of 12 drugs of abuse was demonstrated on the p-BNC platform. Furthermore, the system provided visibility to time-course of select drug and metabolite profiles in oral fluids; for the drug cocaine, three regions of slope were observed that, when combined with concentration measurements from this and prior impairment studies, information about cocaine-induced impairment may be revealed. Conclusions: This chip-based p-BNC detection modality has significant potential to be used in the future by law enforcement officers for roadside drug testing and to serve a variety of other settings, including outpatient and inpatient drug rehabilitation centers, emergency rooms, prisons, schools, and in the workplace