Stratospheric cruise emission reduction program

A recently implemented NASA effort specifically aimed at reducing cruise oxides of nitrogen from high-altitude aircraft is discussed. The desired emission levels and the combustor technology required to achieve them are discussed. A brief overview of the SCERP operating plan is given. Lean premixed-prevaporized combustion and some of the potential difficulties that are associated with applying this technique to gas turbine combustors are examined. Base technology was developed in several key areas. These fundamental studies are viewed as a requirement for successful implementation of the lean premixed combustion technique

Efficiency limits for linear optical processing of single photons and single-rail qubits

We analyze the problem of increasing the efficiency of single-photon sources or single-rail photonic qubits via linear optical processing and destructive conditional measurements. In contrast to previous work we allow for the use of coherent states and do not limit to photon-counting measurements. We conjecture that it is not possible to increase the efficiency, prove this conjecture for several important special cases, and provide extensive numerical results for the general case.Comment: 10 pages, 4 figure

Experience-Based Competency Training in Child and Adolescent Psychotherapy

Background: Compared to adult psychotherapy training, there is little knowledge about the use of standardized actor-patients (SPs) for the development of professional competencies for younger patient populations. Objective: We assessed the effectiveness of two university-based training programs for diagnostic as well as intervention skills in child and adolescent psychotherapy. Methods: Psychology students took part in two courses on the development of diagnostic competencies (NÂ =Â 59) and on intervention skills (NÂ =Â 51). We applied active and experience-based learning strategies, including exercises on self-awareness, mindfulness, peer role-play, and the use of SPs. Competence gain as well as a general evaluation of the seminars were assessed by self-report. Results: For both seminars, self-reported competence increased significantly with a large effect. The retrospective evaluation of learning success and acceptance ratings of the didactic formats were high. Conclusions: Experience-based trainings that include SPs are a feasible option for child and adolescent psychotherapy. The findings are discussed from a conceptual as well as a practical perspective.Hintergrund: Im Vergleich zur Psychotherapieausbildung für Erwachsene fehlt es an Wissen über den Einsatz von standardisierten Schauspielpatient_innen (SP) für die Entwicklung professioneller Kompetenzen für jüngere Patient_innenpopulationen. Fragestellung: Wir untersuchten die Effektivität zweier universitärer Trainings zu diagnostischen und interventionellen Fertigkeiten in der Kinder- und Jugendlichenpsychotherapie. Methoden: Psychologiestudierende nahmen an zwei Kursen zur Entwicklung diagnostischer Kompetenzen (N = 59) und Interventionsfertigkeiten (N = 51) teil. Wir setzten aktive, erfahrungsbasierte Lernstrategien ein, darunter Übungen zur Selbstwahrnehmung, Achtsamkeit, Peer-Rollenspiele und Schauspielpatient_innen. Subjektiver Kompetenzgewinn wurde im Fragebogen sowie durch eine allgemeine Bewertung des Seminars erfasst. Ergebnisse: In beiden Seminaren stieg das subjektive Kompetenzerleben signifikant mit einem großen Effekt an. Retrospektive Bewertung des Lernerfolgs und Akzeptanz der didaktischen Formate waren hoch. Schlussfolgerungen: Erfahrungsbasierte Trainings unter Einbeziehung von SPs für die Kinder- und Jugendlichenpsychotherapie sind machbar. Die Ergebnisse werden unter konzeptuellen und anwendungsbezogenen Aspekten diskutiert

Classical simulation of noninteracting-fermion quantum circuits

We show that a class of quantum computations that was recently shown to be efficiently simulatable on a classical computer by Valiant corresponds to a physical model of noninteracting fermions in one dimension. We give an alternative proof of his result using the language of fermions and extend the result to noninteracting fermions with arbitrary pairwise interactions, where gates can be conditioned on outcomes of complete von Neumann measurements in the computational basis on other fermionic modes in the circuit. This last result is in remarkable contrast with the case of noninteracting bosons where universal quantum computation can be achieved by allowing gates to be conditioned on classical bits (quant-ph/0006088).Comment: 26 pages, 1 figure, uses wick.sty; references added to recent results by E. Knil

Bounds on the Probability of Success of Postselected Non-linear Sign Shifts Implemented with Linear Optics

The fundamental gates of linear optics quantum computation are realized by using single photons sources, linear optics and photon counters. Success of these gates is conditioned on the pattern of photons detected without using feedback. Here it is shown that the maximum probability of success of these gates is typically strictly less than 1. For the one-mode non-linear sign shift, the probability of success is bounded by 1/2. For the conditional sign shift of two modes, this probability is bounded by 3/4. These bounds are still substantially larger than the highest probabilities shown to be achievable so far, which are 1/4 and 2/27, respectively.Comment: 6 page

Imperfect Detectors in Linear Optical Quantum Computers

We discuss the effects of imperfect photon detectors suffering from loss and noise on the reliability of linear optical quantum computers. We show that for a given detector efficiency, there is a maximum achievable success probability, and that increasing the number of ancillary photons and detectors used for one controlled sign flip gate beyond a critical point will decrease the probability that the computer will function correctly. We have also performed simulations of some small logic gates and estimate the efficiency and noise levels required for the linear optical quantum computer to function properly.Comment: 13 pages, 5 figure

Status of SuperSpec: A Broadband, On-Chip Millimeter-Wave Spectrometer

SuperSpec is a novel on-chip spectrometer we are developing for multi-object, moderate resolution (R = 100 - 500), large bandwidth (~1.65:1) submillimeter and millimeter survey spectroscopy of high-redshift galaxies. The spectrometer employs a filter bank architecture, and consists of a series of half-wave resonators formed by lithographically-patterned superconducting transmission lines. The signal power admitted by each resonator is detected by a lumped element titanium nitride (TiN) kinetic inductance detector (KID) operating at 100-200 MHz. We have tested a new prototype device that is more sensitive than previous devices, and easier to fabricate. We present a characterization of a representative R=282 channel at f = 236 GHz, including measurements of the spectrometer detection efficiency, the detector responsivity over a large range of optical loading, and the full system optical efficiency. We outline future improvements to the current system that we expect will enable construction of a photon-noise-limited R=100 filter bank, appropriate for a line intensity mapping experiment targeting the [CII] 158 micron transition during the Epoch of ReionizationComment: 16 pages, 10 figures, Proceedings of the SPIE Astronomical Telescopes + Instrumentation 2014 Conference, Vol 9153, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VI