Utilization survey of prototype structural test article

A survey was conducted of six aerospace companies and two NASA agencies to determine how prototype structural test articles are used in flight operations. The prototype structures are airframes and similar devices which are used for testing and generally are not flown. The survey indicated the following: (1) prototype test articles are not being discarded after development testing is complete, but are used for other purposes, (2) only two cases of prototypes being refurbished and flown were identified, (3) protective devices and inspection techniques are available to prevent or minimize test article damage, (4) substitute programs from design verification are availabel in lieu of using prototype structural articles, and (5) there is a trend away from dedicated test articles. Four options based on these study results were identified to reduce test and hardware costs without compromising reliability of the flight program

Task analysis for error identification: Theory, method and validation

This paper presents the underlying theory of Task Analysis for Error Identification. The aim is to illustrate the development of a method that has been proposed for the evaluation of prototypical designs from the perspective of predicting human error. The paper presents the method applied to representative examples. The methodology is considered in terms of the various validation studies that have been conducted, and is discussed in the light of a specific case study

Relational maintenance: An examination of how gender, relational maintenance strategies, and commitment affect the use of text messages in romantic relationships

This communication study explores the relation between commitment, relational maintenance strategies, and text message use in romantic partners. This study examines how these three factors are connected through the use of surveys. It was hypothesized that romantic partners who were more committed to one another would use text messages to communicate about certain relational maintenance strategies. Results showed romantic partners who used more relational maintenance strategies did in fact use text messages to communicate about these issues more often. Also, couples who were more committed to their partner did use more positivity when communicating through text messages with their partner. It was also found that males use the relational maintenance strategy of openness more often than females when communicating through text messages

Comparing verbal media for alarm handling: Speech versus textual displays

The rise of computers in command and control domains has meant that control operations can be performed via desk-based visual display terminals. This trend has also produced the potential to display information to operators in a variety of formats. Of particular interest has been the use of text-based displays for alarm presentation. There are possible limitations to the use of text for alarm presentation, not least of which is the need for a dedicated alarms display screen (or, at least, a display page). Given the capability of computers to synthesize speech, it is possible that speech-based alarms could generate the same information as text-based displays without the need for dedicated screen space. In this paper an experimental comparison of speech-based and text-based displays for presentation of alarms is reported. The findings show that speech leads to longer response times than text displays, but that it has minimal effect on the efficacy of fault handling. The results are discussed within the alarm initiated activities framework and implications for alarm system design are outlined

WESTT (Workload, Error, Situational Awareness, Time and Teamwork): An analytical prototyping system for command and control

Modern developments in the use of information technology within command and control allow unprecedented scope for flexibility in the way teams deal with tasks. These developments, together with the increased recognition of the importance of knowledge management within teams present difficulties for the analyst in terms of evaluating the impacts of changes to task composition or team membership. In this paper an approach to this problem is presented that represents team behaviour in terms of three linked networks (representing task, social network structure and knowledge) within the integrative WESTT software tool. In addition, by automating analyses of workload and error based on the same data that generate the networks, WESTT allows the user to engage in the process of rapid and iterative “analytical prototyping”. For purposes of illustration an example of the use of this technique with regard to a simple tactical vignette is presented

Sustainable Design: Using Physical Prototypes to Most Benefit Design Students and Environment?

After reviewing the main environmental areas of concern today, this paper will focus on waste management within the area of sustainability. For many years, as part of the design process, physical prototypes were a necessary. This was in order to prove a design‘s functionality and safety. They were expensive, time consuming and, by todays standards wastful. Often, once production began, they were scrapped. The necessity of a physical prototype outweighed all environmental considerations. In the 21st century, with the growth in Computer Aided Engineering (CAE), physical prototypes have nearly been replaced with virtual prototypes. The evidence is overwhelming as to the benfits of virtual prototypes to designers, designs and the environment. This paper will research and identify an area where physical prototypes are still beneficial, that of educating design engineers. A survey of mechanical engineering students over 5 years will identify a significant difference in the basic engineering knowledge of full-time engineering students when compared with their part-time colleagues. The use of physical prototypes can help reduce this difference. This paper argues that physical prototypes, under certain conditions, can reduce waste and still be sustainable

Incomplete beta-function expansions of the solutions to the confluent Heun equation

Several expansions of the solutions to the confluent Heun equation in terms of incomplete Beta functions are constructed. A new type of expansion involving certain combinations of the incomplete Beta functions as expansion functions is introduced. The necessary and sufficient conditions when the derived expansions are terminated, thus generating closed-form solutions, are discussed. It is shown that termination of a Beta-function series solution always leads to a solution that is necessarily an elementary function

Instability of the massive Klein-Gordon field on the Kerr spacetime

We investigate the instability of the massive scalar field in the vicinity of a rotating black hole. The instability arises from amplification caused by the classical superradiance effect. The instability affects bound states: solutions to the massive Klein-Gordon equation which tend to zero at infinity. We calculate the spectrum of bound state frequencies on the Kerr background using a continued fraction method, adapted from studies of quasinormal modes. We demonstrate that the instability is most significant for the $l = 1$, $m = 1$ state, for $M \mu \lesssim 0.5$. For a fast rotating hole ($a = 0.99$) we find a maximum growth rate of $\tau^{-1} \approx 1.5 \times 10^{-7} (GM/c^3)^{-1}$, at $M \mu \approx 0.42$. The physical implications are discussed.Comment: Added references. 27 pages, 7 figure

Sustaining a Balanced Calendar in Hopewell City Public Schools

As the first school division in Virginia to implement a division-wide year-round school calendar, Hopewell City Public schools requested assistance in evaluating the impact of their work. In light of the COVID-19 pandemic the division paused implementation, shifting the focus of the study from evaluation to providing recommendations for structural, philosophical, and fiscal changes to the year round calendar initiative and its associated communication plan that would positively impact the long term sustainability of the initiative. The study employed a mixed methods approach including survey and focus group data along with an extensive literature review, and internal document and analysis. Findings suggested that creating structures to ensure sound instructional leadership during intersession instruction and the creation of career and life readiness pathways through vertical and horizontal intersession planning are critical in driving positive student outcomes. Additional findings identified a community where members that indicated they understood the initiative were more likely to support the initiative, and a cost analysis found stable and sustainable fiscal management. These findings were used first to inform a recommendation for a distributed leadership approach to monitoring student progress and effective intersession pedagogy. Further, recommendations informed the development of a communication plan designed to increase awareness and sustainable community support by celebrating and showcasing growth in students’ life and career readiness skills. By ensuring the recommended instructional and communication conditions Hopewell City Public Schools will be able to sustain internal and external support for the Balanced Calendar initiative over time