EV space suit gloves (passive)

A pair of pressure and thermal insulating overgloves to be used with an Extravehicular (EV) suit assembly was designed, developed, fabricated, and tested. The design features extensive use of Nomex felt materials in lieu of the multiple layer insulation formerly used with the Apollo thermal glove. The glove theoretically satisfies all of the thermal requirements. The presence of the thermal glove does not degrade pressure glove tactility by more than the acceptable 10% value. On the other hand, the thermal glove generally degrades pressure glove mobility by more than the acceptable 10% value, primarily in the area of the fingers. Life cycling tests were completed with minimal problems. The thermal glove/pressure glove ensemble was also tested for comfort; the test subjects found no problems with the thermal glove although they did report difficulties with pressure points on the pressure glove which were independent of the thermal glove

Computer Components and Systems

Contains research objectives.U.S. Navy Bureau of Ships under Contracts NObsr 72716 and NObsr 7760

Feasibility of a chemical poison loop system

Chemical poison loop system for reactivity control of tungsten water moderated rocket reacto

The NASA/MSFC global reference atmospheric model: MOD 3 (with spherical harmonic wind model)

Improvements to the global reference atmospheric model are described. The basic model includes monthly mean values of pressure, density, temperature, and geostrophic winds, as well as quasi-biennial and small and large scale random perturbations. A spherical harmonic wind model for the 25 to 90 km height range is included. Below 25 km and above 90 km, the GRAM program uses the geostrophic wind equations and pressure data to compute the mean wind. In the altitudes where the geostrophic wind relations are used, an interpolation scheme is employed for estimating winds at low latitudes where the geostrophic wind relations being to mesh down. Several sample wind profiles are given, as computed by the spherical harmonic model. User and programmer manuals are presented

THE DETERMINANTS OF FOOD STAMP PROGRAM PARTICIPATION

Food Security and Poverty,

FARM COMMODITY PAYMENT LIMITS: WHAT IMPACT WILL THEY HAVE ON THE ECONOMIC VIABILITY OF SOUTHEASTERN AGRICULTURE?

Agricultural and Food Policy,

Influence of third harmonic injection on MMC-based HVDC transmission systems

Whilst third harmonic injection is extensively used in modular multilevel converter (MMC) control, its significant advantages over sinusoidal modulation have not been fully explored. This paper evaluates the influence of third harmonic injection on system power losses, submodule capacitance, circulating current, and fault current and mathematical models are derived. Station conduction losses are reduced by 11%, yielding higher efficiency and lowering cooling system capacity. The submodule capacitance is reduced by 24%, which significantly lowers the capital cost, weight, and volume of the station converter. Additionally, the phase energy variation is reduced by around 18%, which benefits circulating current control. Due to the lower AC currents, the semiconductor current stresses are correspondingly reduced. In addition to the performance improvement in normal operation, the third harmonic injection reduces the DC fault currents by 13.4% and thus the fault current stresses on semiconductors and DC circuit breakers are lowered. Simulation of a point-to-point HVDC system demonstrates the effectiveness of the above analysis

Molecular Dynamics Simulation of Polymer-Metal Bonds

Molecular simulation is becoming a very powerful tool for studying dynamic phenomena in materials. The simulation yields information about interaction at length and time scales unattainable by experimental measurements and unpredictable by continuum theories. This is especially meaningful when referring to bonding between a polymer and a metal substrate. A very important characteristic of polymers is that their physical properties do not rely on the detailed chemical structure of the molecular chains but only on their flexibility, and accordingly they will be able to adopt different conformations. In this paper, a molecular simulation of the bonding between vinyl ester polymer and steel is presented. Four different polymers with increasing chain lengths have been studied. Atomic co-ordinates are adjusted in order to reduce the molecular energy. Conformational changes in the macromolecules have been followed to obtain the polymer pair correlation function. Radius of gyration and end-to-end distance distributions of the individual chains have been used as a quantitative measurement of their flexibility. There exists a correlation between flexibility of the molecular chains and the energy of adhesion between the polymer and the metal substrate. Close contacts between the two materials are established at certain points but every atom up to a certain distance from the interface contributes to the total value of the adhesion energy of the system

Examining the empathic voice teacher

Empathy enables successful communication and connection between teachers and their students, yet few studies have investigated its specific use in teaching singing. Addressing this gap, we interviewed voice teachers to discover how they articulate their pedagogy in terms of empathic practices and observed one-to-one lessons for evidence of the same. A sample of 27 classical and music theater voice teachers in Australia (70% females, 30% males), aged 35 to 75years old (M=55) were interviewed. Of this cohort, seven teachers were observed in their one-to-one teaching practices. Interviews and observations were analyzed using Interpretative Phenomenological Analysis. Results indicated that voice teachers tailor their practices to the needs of students and demonstrate characteristics of teacher empathy identified in previous literature: effective communication, positive relationships, care, welcoming learning environment, trust, morality, and listening. Empathic teaching facilitates an individualized approach in which singing students are supported and motivated in their own autonomous learning environment. These findings have implications for voice pedagogy that features the use of empathy to benefit future students

"I ask them what they can feel": proprioception and the voice teacher’s approach

Background: Proprioception is considered essential to forming an aesthetic vocal experience, particularly musculoskeletal proprioception or the ability to accurately sense position, movement, effort, muscular tension, sensation of posture, and balance when singing. Research into singing reveals that proprioceptive awareness leads to better coordination and enhances the singer’s overall understanding of their vocal function. While proprioception is also considered useful in vocal pedagogy, few studies have examined if/how proprioception contributes to voice teaching in the one-to-one context. Aims: This project sought to understand in what way proprioception featured in the practices of tertiary classical and music theatre voice teachers. It specifically aimed to: 1) identify ways in which voice teachers demonstrate proprioceptive awareness when discussing their practices; and 2) observe how, and for what purpose, voice teachers engage proprioception when delivering voice lessons. Method: A multiple-case study design involved interviews with teachers and observations of their lessons. Voice teachers (N=7, all working in Australia), selected through purposive sampling, were interviewed face-to-face and each was observed delivering three lessons (N=21) to professionally focused singing students. Interview transcripts and observation field notes were analysed using Interpretive Phenomenological Analysis. Results: Voice teachers revealed proprioceptive awareness when discussing their practices, such as sensing discomfort when a student sang with vocal tension. They also appeared to utilise proprioception as a diagnostic tool when addressing technical issues for their students. Further, teachers sought to develop proprioceptive awareness in their students through physical touch, verbal feedback, muscle release work, external tools (e.g., resistance bands), and breathwork. This was particularly evident where teachers focused students on how they felt when they were singing. Conclusions: Voice teachers adopted a proprioceptive style of teaching, literally adopting a ‘hands-on’ approach and also asking students to reflect on their own physical sensations rather than on the sounds they were making. Further, voice teachers were shown to be developing proprioceptive awareness in their students to aid in achieving the complex sensorimotor coordination required in singing. Implications: These findings have implications regarding vocal pedagogy courses training voice teachers to incorporate proprioceptive awareness in their practices