12,399 research outputs found

    High voltage solid-state relay

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    Hybrid microelectronics relay has characteristics significantly superior to conventional solid state relays. Relay provides 2500 Vdc input to output isolation and operates from high threshold logic signal to switch load of 400 Vdc at 2 mA. Technology should be of interest to manufacturers of discrete components

    Antimicrobial Susceptibilities of Aerobic Isolates from Respiratory Samples of Young New Zealand Horses

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    3rd Annual IEEE Energy Conversion Congress and Exposition, ECCE 2011, Phoenix, AZ, 17-22 September 2011This paper presents a method of mitigating the transient overshoots of DC-DC converters operating with large load disturbances. The method involves a small auxiliary power circuit with a complementary control scheme that provides a smooth absorption and release of excess energy from and to the main DC-DC converter in the events of large load changes. This control mechanism interactively mitigates the large transient overshoots which would otherwise appear at the converter output. Since the control scheme involves an adjustable-energy-storage feature, the proposed solution is effective for any level of step-load change within a pre-specified range.Department of Electronic and Information EngineeringRefereed conference pape

    Multilayered printed circuit boards inspected by X-ray laminography

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    Technique produces high resolution cross-sectional radiographs with close interplane spacing for inspecting multilayer boards to be used in providing circuitry routing and module structural support

    Professional practices, training, and funding mechanisms: A survey of pediatric primary care psychologists

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    The integration of mental health services in primary care settings has expanded rapidly in recent years with psychologists being at the forefront of efforts to promote healthy behaviors, reduce disease, and care for behavioral, emotional, and developmental needs to promote overall health and well-being for children and families (Asarnow, Kolko, Miranda,&Kazak, 2017; Stancin& Perrin, 2014). While there are many psychologists working in pediatric primary care (PPC), little is known about the specific activities that these psychologists engage in, the training they receive, or funding mechanisms that support their work. This study sought to address this gap in the literature through a survey of psychologists working in PPC. An anonymous online survey was disseminated to members of professional organizations and listservs who were identified as having interest in PPC. Psychologists (N-65) currently practicing in PPC completed the survey by reporting on clinical roles and practices, professional training, practice settings, and funding supports in PPC settings. Results indicate that psychologists assume a number of roles in PPC including providing individual and family therapy, conducting screenings for child mental health concerns, and providing consultation to medical colleagues. Many psychologists also provide supervision and offer educational opportunities for those in related fields, such as medicine and social work. Engagement in research activities was identified as a secondary activity. It was reported that a number of clinical activities were not billed for on a regular basis. Additional areas of research will be discussed along with implications for clinical services in PPC.. © 2017 American Psychological Association

    Luminescent hyperbolic metasurfaces.

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    When engineered on scales much smaller than the operating wavelength, metal-semiconductor nanostructures exhibit properties unobtainable in nature. Namely, a uniaxial optical metamaterial described by a hyperbolic dispersion relation can simultaneously behave as a reflective metal and an absorptive or emissive semiconductor for electromagnetic waves with orthogonal linear polarization states. Using an unconventional multilayer architecture, we demonstrate luminescent hyperbolic metasurfaces, wherein distributed semiconducting quantum wells display extreme absorption and emission polarization anisotropy. Through normally incident micro-photoluminescence measurements, we observe absorption anisotropies greater than a factor of 10 and degree-of-linear polarization of emission >0.9. We observe the modification of emission spectra and, by incorporating wavelength-scale gratings, show a controlled reduction of polarization anisotropy. We verify hyperbolic dispersion with numerical simulations that model the metasurface as a composite nanoscale structure and according to the effective medium approximation. Finally, we experimentally demonstrate >350% emission intensity enhancement relative to the bare semiconducting quantum wells

    The Non-thermal Radio Jet Toward the NGC 2264 Star Formation Region

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    We report sensitive VLA 3.6 cm radio observations toward the head of the Cone nebula in NGC 2264, made in 2006. The purpose of these observations was to study a non-thermal radio jet recently discovered, that appears to emanate from the head of the Cone nebula. The jet is highly polarized, with well-defined knots, and one-sided. The comparison of our images with 1995 archive data indicates no evidence of proper motions nor polarization changes. We find reliable flux density variations in only one knot, which we tentatively identify as the core of a quasar or radio galaxy. An extragalactic location seems to be the best explanation for this jet.Comment: 12 pages, 5 figure

    The Whole Heliosphere Interval in the Context of a Long and Structured Solar Minimum: An Overview from Sun to Earth

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    Throughout months of extremely low solar activity during the recent extended solar-cycle minimum, structural evolution continued to be observed from the Sun through the solar wind and to the Earth. In 2008, the presence of long-lived and large low-latitude coronal holes meant that geospace was periodically impacted by high-speed streams, even though solar irradiance, activity, and interplanetary magnetic fields had reached levels as low as, or lower than, observed in past minima. This time period, which includes the first Whole Heliosphere Interval (WHI 1: Carrington Rotation (CR) 2068), illustrates the effects of fast solar-wind streams on the Earth in an otherwise quiet heliosphere. By the end of 2008, sunspots and solar irradiance had reached their lowest levels for this minimum (e.g., WHI 2: CR 2078), and continued solar magnetic-flux evolution had led to a flattening of the heliospheric current sheet and the decay of the low-latitude coronal holes and associated Earth-intersecting high-speed solar-wind streams. As the new solar cycle slowly began, solar-wind and geospace observables stayed low or continued to decline, reaching very low levels by June – July 2009. At this point (e.g., WHI 3: CR 2085) the Sun–Earth system, taken as a whole, was at its quietest. In this article we present an overview of observations that span the period 2008 – 2009, with highlighted discussion of CRs 2068, 2078, and 2085. We show side-by-side observables from the Sun’s interior through its surface and atmosphere, through the solar wind and heliosphere and to the Earth’s space environment and upper atmosphere, and reference detailed studies of these various regimes within this topical issue and elsewhere
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