Frequency-Tunable Josephson Junction Resonator for Quantum Computing

We have fabricated and measured a high-Q Josephson junction resonator with a tunable resonance frequency. A dc magnetic flux allows the resonance frequency to be changed by over 10 %. Weak coupling to the environment allows a quality factor of $\thicksim$7000 when on average less than one photon is stored in the resonator. At large photon numbers, the nonlinearity of the Josephson junction creates two stable oscillation states. This resonator can be used as a tool for investigating the quality of Josephson junctions in qubits below the single photon limit, and can be used as a microwave qubit readout at high photon numbers.Comment: 3 pages, 5 figure

Self-contained breathing apparatus

A self-contained breathing apparatus with automatic redundant fluid pressure controls and a facemask mounted low pressure whistle alarm is described. The first stage of the system includes pair of pressure regulators connected in parallel with different outlet pressures, both of which reduce the pressure of the stored supply gas to pressures compatible with the second stage breathing demand regulator. A primary regulator in the first stage delivers a low output pressure to the demand regulator. In the event of a failure closed condition of the primary regulator an automatic transfer valve switches on the backup regulator. A warning that the supply pressure has been depleted is also provided by a supply pressure actuated transfer valve which transfers the output of the first stage pressure regulators from the primary to the backup regulator. The alarm is activated in either the failure closed condition or if the supply pressure is reduced to a dangerously low level

Pictures Past: A Centennial Celebration of Utah State University

This book does not pretend to present a comprehensive history of Utah State University. It cannot. It presents glimpses of that institution, glimpses that can be documented by the photographs preserved in University Archives. Entire areas of the University\u27s past are ignored for no better reason than that no one had an available camera to record them; or that, once recorded, they never found their way into University Archives. The entire story is not told. That is the responsibility of another. I leave it to him. And if these pages are much concerned with the early years when the institution was new, I can only plead that there is where the author\u27s interests are also centeredwhen the land was new and when beginnings were made. This is my book. That must be clearly said, lest others receive opprobrium for the choices and conclusions that are mine alone. Thanks are due to those who tolerated my intolerable delays in producing it and to one who has helped in minimizing the delays and enriching the result: Jeannie. This is my book. It is dedicated to the memory of Andrew Charles Simmonds, I, 1872-1947, who enrolled at Utah State on January 5, 1892-and who wouldn\u27t have believed what\u27s happened since.https://digitalcommons.usu.edu/usufaculty_monographs/1053/thumbnail.jp

Tables and charts of equilibrium thermodynamic properties of ammonia for temperatures from 500 to 50,000 K.

Equilibrium thermodynamic properties for pure ammonia were generated for a range of temperature from 500 to 50,000 K and pressure from 0.01 to 40 MN/sq m and are presented in tabulated and graphical form. Properties include pressure, temperature, density, enthalpy, speed of sound, entropy, molecular-weight ratio, specific heat at constant pressure, specific heat at constant volume, isentropic exponent, and species mole fractions. These properties were calculated by the method which is based on minimization of the Gibbs free energy. The data presented herein are for an 18-species ammonia model. Heats of formation and spectroscopic constants used as input data are presented. Comparison of several thermodynamic properties calculated with the present program and a second computer code is performed for a range of pressure and for temperatures up to 30,000 K

Demonstration of efficient nonreciprocity in a microwave optomechanical circuit

The ability to engineer nonreciprocal interactions is an essential tool in modern communication technology as well as a powerful resource for building quantum networks. Aside from large reverse isolation, a nonreciprocal device suitable for applications must also have high efficiency (low insertion loss) and low output noise. Recent theoretical and experimental studies have shown that nonreciprocal behavior can be achieved in optomechanical systems, but performance in these last two attributes has been limited. Here we demonstrate an efficient, frequency-converting microwave isolator based on the optomechanical interactions between electromagnetic fields and a mechanically compliant vacuum gap capacitor. We achieve simultaneous reverse isolation of more than 20 dB and insertion loss less than 1.5 dB over a bandwidth of 5 kHz. We characterize the nonreciprocal noise performance of the device, observing that the residual thermal noise from the mechanical environments is routed solely to the input of the isolator. Our measurements show quantitative agreement with a general coupled-mode theory. Unlike conventional isolators and circulators, these compact nonreciprocal devices do not require a static magnetic field, and they allow for dynamic control of the direction of isolation. With these advantages, similar devices could enable programmable, high-efficiency connections between disparate nodes of quantum networks, even efficiently bridging the microwave and optical domains.Comment: 9 pages, 6 figure

An inlet analysis for the NASA hypersonic research engine aerothermodynamic integration model

A theoretical analysis for the inlet of the NASA Hypersonic Research Engine (HRE) Aerothermodynamic Integration Model (AIM) has been undertaken by use of a method-of-characteristics computer program. The purpose of the analysis was to obtain pretest information on the full-scale HRE inlet in support of the experimental AIM program (completed May 1974). Mass-flow-ratio and additive-drag-coefficient schedules were obtained that well defined the range effected in the AIM tests. Mass-weighted average inlet total-pressure recovery, kinetic energy efficiency, and throat Mach numbers were obtained

Defect Visualization and Location of Reinforcing Bars and Cables in Concrete Using Active Electromagnetic Induction Imaging

Reinforced concrete is used to build many modern structures such as bridges and buildings. The strength of these structures is dependent upon the integrity of the steel reinforcing embedded in the concrete. Over a period of time the rebars may begin to corrode and crack. The loss of steel due to corrosion or the loss of strength due to cracking may lead to structural failure particularly for prestressed concrete. The work described in this paper is the development of active electromagnetic induction sensors capable of detecting reinforcing bars within concrete and the identification of surface breaking defects on the reinforcing bars

Two Departments, Two Models of Interdisciplinary Peer Learning

On graduation, teacher candidates (TCs) are typically underprepared to teach science, particularly physical science, whereas physics graduates frequently lack training in teaching or effective communication. In response, we created two models for interdisciplinary peer learning where TCs were paired with either graduate or undergraduate physics students. In both models, physics students teach TCs content knowledge relevant to a given area of either classical or quantum physics, which TCs then use to design and implement a short lesson for K-5 students. Overall, both models were successful, with the two sets of students reporting benefits in each case. Affordances for TCs included increased confidence to teach physical science and an appreciation for collaboration with experts. Physics students described increased awareness of the complexities of communicating science to general audiences and stronger community with their classmates. Students from both groups cited insufficient project time as a constraint, whereas physics students found it challenging to align their project and coursework. In moving away from traditional lecture, these interdisciplinary collaborations also benefitted us as instructors, giving us new perspectives on teaching. In light of our findings we propose improvements to these proof-of-concept models to enable their future scale-up and replication in other disciplines

Parental perceptions of bladder dysfunction in children with symptomatic joint hypermobility

Children with symptomatic joint hypermobility (SJH) report chronic pain, fatigue, and joint instability as their main symptoms. Symptoms can extend beyond musculoskeletal and include lower urinary tract dysfunction (LUTD). There are no studies exploring parent-perceived quality of life (QoL) in children with LUTD, or strategies used to manage symptoms in this population. Our online cross-sectional survey assessed parents of 6–18-year-olds via two UK charitable organizations. It included the Pediatric Incontinence Questionnaire (PinQ), the Dysfunctional Voiding Symptom Score, and questions exploring treatments and efficacy. Sixty-seven parental questionnaires were analyzed. The majority of children were white females (95%, n = 64). Urgency (97%, n = 65) and enuresis (41.7%, n = 28) were the most frequently reported symptoms. The PinQ questionnaire showed that children were emotionally distressed by LUTD. Twenty-nine parents (43%, n = 29) reported pharmacotherapy as the most effective treatment. Few had accessed other treatments such as physiotherapy (16%, n = 18). Most parents reported that overall treatment did not meet their expectations. This study highlights that parents perceive LUTD as having a great impact on their child's QoL. There is need for education among clinicians about LUTD and hypermobility-related disorders, and for development and evaluation of treatments