A study of sound generation in subsonic rotors, volume 2

Computer programs were developed for use in the analysis of sound generation by subsonic rotors. Program AIRFOIL computes the spectrum of radiated sound from a single airfoil immersed in a laminar flow field. Program ROTOR extends this to a rotating frame, and provides a model for sound generation in subsonic rotors. The program also computes tone sound generation due to steady state forces on the blades. Program TONE uses a moving source analysis to generate a time series for an array of forces moving in a circular path. The resultant time series are than Fourier transformed to render the results in spectral form. Program SDATA is a standard time series analysis package. It reads in two discrete time series and forms auto and cross covariances and normalizes these to form correlations. The program then transforms the covariances to yield auto and cross power spectra by means of a Fourier transformation

A study of sound generation in subsonic rotors, volume 1

A model for the prediction of wake related sound generation by a single airfoil is presented. It is assumed that the net force fluctuation on an airfoil may be expressed in terms of the net momentum fluctuation in the near wake of the airfoil. The forcing function for sound generation depends on the spectra of the two point velocity correlations in the turbulent region near the airfoil trailing edge. The spectra of the two point velocity correlations were measured for the longitudinal and transverse components of turbulence in the wake of a 91.4 cm chord airfoil. A scaling procedure was developed using the turbulent boundary layer thickness. The model was then used to predict the radiated sound from a 5.1 cm chord airfoil. Agreement between the predicted and measured sound radiation spectra was good. The single airfoil results were extended to a rotor geometry, and various aerodynamic parameters were studied

Medicare-Centered Curriculum For Limited English Proficient Beneficiaries

Medicare is the primary health insurance for retirees and those with disabilities in U.S. Currently there are tens of millions who access Medicare and its rate is projected to increase in the future. Medicare is composed of different Parts and there are rules for eligibility. Within the respective Parts a retiree needs to choose various options and as an additional layer, those Parts are offered by different insurers. Further, Medicare beneficiaries need to understand how the different Parts of Medicare work together and are financed, and who is responsible for paying for the different components and Parts. Retirees also need to have an understanding of the ramifications of their Medicare choices. This capstone addressed the question: What might an instructional healthcare curriculum for limited English proficient (LEP) adults who are retiring look like? The capstone describes the history of Medicare, communication practices for federal documents and specifically the Medicare & You handbook. The capstone delves into communication practices specifically for LEP retirees, LEP retirees’ engagement with the healthcare system and community-based adult education programs. Based on the need of providing a curriculum that started with foundational information and worked into higher-order processing, Bloom’s Revised Taxonomy was used as a framework for the lesson plan. The curriculum starts with beginning knowledge of Medicare and insurance terms and moves to higher levels of comparing and contrasting Medicare policies. While the curriculum was originally constructed for an audience of high intermediate LEP adults, it is believed that it may be expanded to include many in Medicare audience. The hope is that this curriculum can be used to assist retirees navigate the often confusing Medicare system

“Everyone happy with what their role is?”: A pragmalinguistic evaluation of leadership practices in emergency medicine training

This article reports a study of simulated interactions between emergency medical teams, as they are used in education for specialist trainee doctors. We focus on a key area of communicative competence that trainees are assessed on: the performance of leadership skills. Using videos of simulated trauma cases recorded within a training department of a large teaching hospital in the UK, we analyse how trainee doctors delegate tasks to their teams, matching up their linguistic performance, in particular their use of requests, to how they are assessed in the simulation overall. This allows us to establish the types of linguistic leadership performance that are evaluated positively in this setting and therefore are attributed to success. Through fine-grained, qualitative analysis, we examine the interrelationship between ‘efficiency’, evidenced by the subsequent successful completion of an action by the team, and the use of indirect and mitigated requests, finding that a high number of indirect forms are successfully used to make requests of others in this time-pressured setting. We discuss the theoretical implications of our observations, revisiting claims about linguistic behaviour in urgent contexts, and also consider the practical implications of the study, including professional practice and training

On toric varieties which are almost set-theoretic complete intersections

We describe a class of affine toric varieties $V$ that are set-theoretically minimally defined by codim $V+1$ binomial equations over fields of any characteristic

Scalable and ultralow power silicon photonic two-dimensional phased array

Photonic integrated circuit based optical phased arrays (PIC-OPA) are emerging as promising programmable processors and spatial light modulators, combining the best of planar and free-space optics. Their implementation in silicon photonic platforms has been especially fruitful. Despite much progress in this field, demonstrating steerable two-dimensional (2D) OPAs scalable to a large number of array elements and operating with a single wavelength has proven a challenge. In addition, the phase shifters used in the array for programming the far field beam are either power hungry or have a large footprint, preventing implementation of large scale 2D arrays. Here, we demonstrate a two-dimensional silicon photonic phased array with high-speed (~330 KHz) and ultralow power microresonator phase-shifters with a compact radius (~3 {\mu}m) and 2{\pi} phase shift ability. Each phase-shifter consumes an average ~250 {\mu}W static power for resonance alignment and ~50 {\mu}W power for far field beamforming. Such PIC-OPA devices can enable a new generation of compact and scalable low power processors and sensors

The impact of resources on decision making

Decision making is a significant activity within industry and although much attention has been paid to the manner in which goals impact on how decision making is executed, there has been less focus on the impact decision making resources can have. This article describes an experiment that sought to provide greater insight into the impact that resources can have on how decision making is executed. Investigated variables included the experience levels of decision makers and the quality and availability of information resources. The experiment provided insights into the variety of impacts that resources can have upon decision making, manifested through the evolution of the approaches, methods, and processes used within it. The findings illustrated that there could be an impact on the decision-making process but not on the method or approach, the method and process but not the approach, or the approach, method, and process. In addition, resources were observed to have multiple impacts, which can emerge in different timescales. Given these findings, research is suggested into the development of resource-impact models that would describe the relationships existing between the decision-making activity and resources, together with the development of techniques for reasoning using these models. This would enhance the development of systems that could offer improved levels of decision support through managing the impact of resources on decision making

Coherent acoustic control of a single silicon vacancy spin in diamond

Phonons are considered to be universal quantum transducers due to their ability to couple to a wide variety of quantum systems. Among these systems, solid-state point defect spins are known for being long-lived optically accessible quantum memories. Recently, it has been shown that inversion-symmetric defects in diamond, such as the negatively charged silicon vacancy center (SiV), feature spin qubits that are highly susceptible to strain. Here, we leverage this strain response to achieve coherent and low-power acoustic control of a single SiV spin, and perform acoustically driven Ramsey interferometry of a single spin. Our results demonstrate an efficient method of spin control for these systems, offering a path towards strong spin-phonon coupling and phonon-mediated hybrid quantum systems

Identifying challenges in quantifying uncertainty: Case study in infrared thermography

Complex engineering systems present a wealth of uncertainties concerning aspects ranging from performance measurements to maintainability and through-life characteristics. A quantifiable understanding of these uncertainties is vital to system optimisation and plays a key role in decision-making processes for manufacturing organisations worldwide; impacting profit, product availability and manufacturing efficiency. The aim of this paper is to examine challenges and complications that arise when quantifying uncertainties in complex engineering systems that rely on expert opinion. A thermographic inspection system is utilised as a use case. Contractor-client and supervisor-maintainer relationships are examined. Key challenges highlighted involve accurate depiction of error margins and corresponding uncertainties of components where data is only heuristically obtainable, as well as the influence of environmental conditions and skill of the maintainer