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This article documents the beginning of the intellectual companionship between the founder of ethnomethodology, Harold Garfinkel, and Edward Rose, who is most often associated with his program of "ethno‐inquiries." I present results from archival research focusing on the contacts and collaborations between Rose and Garfinkel in the years 1955–1965. First, I describe the review process for Rose and Felton's paper, submitted to the American Sociological Review in 1955, which Garfinkel reviewed and after Rose's rebuttal recommended for publication. The paper induced Garfinkel to write an extensive commentary that has remained unpublished. Second, I discuss the 1958 New Mexico conference sponsored by the Air Force, which was an opportunity for Rose and Garfinkel to work together on topics related to common‐sense knowledge and scientific knowledge. Third, I give an overview of the ethnomethodological conferences in 1962 and 1963, supported by an Air Force grant written collaboratively by Rose and Garfinkel. Here I focus primarily on Rose's research on "small languages," which stimulated many discussions among the early ethnomethodologists. Rose's work and exchanges with Garfinkel demonstrate the former's affinity for miniaturization as a research approach and search for ways to empiricize topics of sociological theory in locally observable settings. [ABSTRACT FROM AUTHOR]

A University Affiliated Research Center (UARC) is a highly valued engineering, research, and development resource to the federal government, largely within the US Department of Defense (DoD). Only 15 exist, all under special authority of the US Code. The Systems Engineering Research Center (SERC), established in 2008, was the first UARC established as a networked research center, gradually growing to include more than two dozen university members, each offering systems engineering research capabilities. This networked model for a UARC has found support within the DoD—exemplified by the newest UARC established recently by the US Air Force. A large diverse pool of faculty and student researchers arguably delivers the most consequential academic research in systems engineering anywhere in the world. In its first few years, the SERC had to overcome challenges that single‐university UARCs did not face in exchange for the advantages that such a sizable network of universities offers. This review paper explores those challenges, offering lessons for new network‐based UARCs and other network‐based university research centers. Systems engineering communities, globally, are exploring such constructs, and this reflective paper may offer useful insights. [ABSTRACT FROM AUTHOR]

Digital Engineering (DE) and Model‐Based Systems Engineering (MBSE) are transforming existing acquisition processes. Little extant research exists regarding validation of digital system models. In the traditional "design‐build‐test" method, stakeholder requirements validation occurs near the end of development. However, DE is described as a "model‐analyze‐build" approach where validation is required earlier in the lifecycle to refine and add digital elements to the authoritative source of truth. This paper describes a framework for model‐based design reviews (MBDR) and extends previous work by Hecht and Chen. Validation use case development is emphasized to capture both the intent, the "why," and the evidence, the "what," required to enter or exit a preliminary design review (PDR). Model requirements are derived from model use cases, and validation test cases enable automated and manual assessment of quality, completeness, and consistency. The framework is successfully prototyped on a small unmanned airborne system (sUAS) model created for a graduate course PDR. There appears to be wide interest across the U.S. Air Force for a similar framework. [ABSTRACT FROM AUTHOR]

This paper reviews the life of Prof. Henry Charnock. He was a President of the Royal Meteorological Society (1982–1984) whose expertise spanned both the atmosphere and ocean. He started as a meteorological forecaster with the Royal Air Force during WWII and went on to study air–sea interaction and the structure of the upper ocean. He later exerted considerable influence on the shape of both United Kingdom and international marine science. [ABSTRACT FROM AUTHOR]

The Polish TU 154M plane, Polish Air Force Flight 101, had crashed near Smolensk on 10th of April 2010. The crash was investigated by The Interstate Aviation Committee, whose conclusions were questioned by a number of Polish scientists. The cause of the crash still appears to be incompletely documented and requires additional evidence. In this paper, investigations of a solid material eluted from a piece of cloth of one of the victims of the crash are described. High resolution mass spectrometry was applied to analyze the soot left after controlled ethylene oxide (EO) explosions, performed under different conditions. These included electric ignition of EO vapors in a large volume steel container, and explosions of glass tubes filled with liquid EO, stimulated by thermally initiated explosions of pentaerythritol tetranitrate (PETN). One of these explosions was conducted in the vessel used for the electric ignition of EO and the other in a hermetically locked, small volume container. It was shown that the soot comprises a set of C2H4O homopolymers and copolymers whose characteristic MS patterns are condition‐dependent. The MS spectrum of the postcrash sample referred to above reveals a number of polymers that are also present in the soot obtained in PETN‐initiated ethylene oxide explosions. It can be concluded that the piece of cloth was subjected to an EO explosion initiated by an explosion of energetic material, possibly PETN. Similar control experiments with ethylene glycol (EG) showed that the polymers identified in the investigated postcrash sample could not originate from exploding EG. [ABSTRACT FROM AUTHOR]

The exploration of electromagnetic vibration sources is very important for the vibroacoustic reduction of a squirrel‐cage induction motor. However, the influence of high‐order electromagnetic force on the electromagnetic vibration of induction motor has not been studied before. The influence of high‐order electromagnetic force on motor vibration is investigated in detail. Firstly, the Maxwell stress tensor method is applied to calculate the electromagnetic force. Next, the force transfer function is introduced to describe the phenomenon that the high‐order electromagnetic force induces the low‐mode motor vibration. Then, the high‐order forces in the air gap of the induction motor are analysed in detail and their effects on motor vibration are simulated. Finally, an experiment is conducted to verify the correctness of the analytical scheme. [ABSTRACT FROM AUTHOR]

The two‐fluid single‐column model of Thuburn et al. (Quart. J. R. Meteorol. Soc., 2019, 145, 1535–1550) is extended to include moisture and horizontal wind shear. Turbulent kinetic energy is introduced as a prognostic variable, dependence on a diagnosed boundary‐layer height is removed, and subfilter fluxes are approximated using a two‐fluid version of a Mellor–Yamada scheme. Three mechanisms for entrainment and detrainment processes are introduced, which represent entrainment of unstable air at the surface, forced detrainment of air at the top of the boundary/cloud layers, and turbulent mixing that relaxes the convective fluid to a reference profile. A semi‐implicit Eulerian discretization replaces the semi‐implicit semi‐Lagrangian implementation of Thuburn et al. (Quart. J. R. Meteorol. Soc., 2019, 145, 1535–1550) to improve numerical stability and conservation. The equations for the implicit time step are solved using a quasi‐Newton method, which is shown to perform well in numerical tests for conservation and convergence. The two‐fluid single‐column model presented in this article will be applied to simulations of shallow cumulus convection in Part III. [ABSTRACT FROM AUTHOR]

The maintenance conversion scheduling problem (MCSP) is faced by organizations such as those in the airline, defense, heavy equipment, and transportation industries switching from an asset maintenance program with longer, less‐frequent service visits to one with shorter, more frequent visits. One example is the United States Air Force (USAF) High Velocity Maintenance program piloted at the Warner Robbins Air Logistics Center on the C‐130 aircraft line. The USAF MCSP is complex, as planners must schedule significantly more aircraft depot maintenance visits during the conversion period and must determine the timing and specific order in which each aircraft completes a repetitive sequence of maintenance visits. The conversion is expected to yield a stable long‐term maintenance schedule, while balancing annual depot workload and operating within reasonable flow times and work‐in‐process levels. While practically important, this problem has received little to no attention in the literature. Therefore, this research formalizes the general MCSP within an optimization framework, shows the MCSP is NP‐complete, proposes a computationally effective solution approach, and shows that a balanced long‐term schedule depends critically on the conversion period schedule. Our solutions are markedly better than USAF proposed schedules and underscore the value of leveraging synergies between asset availability and maintenance efficiency. Our approach moves the focus away from batch scheduling toward a smoother, more uniform, mixed‐model type schedule that yields more stable maintenance operations and a more consistent, predictable level of aircraft readiness. The manuscript concludes with a discussion of the main theoretical and practical implications of our work. [ABSTRACT FROM AUTHOR]

Diethard Böhme has had a long career covering many topics in ion‐molecule reactivity. In this review, we describe the work done at the Air Force Research Laboratory (and its variously named preceding organizations) that was inspired by his studies. These fall into two main areas: nucleophilic displacement (SN2) and metal cation chemistry. In SN2 chemistry, we revisited many of the reactions Diethard pioneered and studied them in more detail. We found nonstatistical behavior, both competition and noncompetition between multiple channels. New channels were found as hydration occurred, with more solution‐like behavior occurring as only a few ligands were added. Temperature‐dependent studies revealed details that were not observable at room temperature. These and other highlights will be discussed. In metal cation reactions, Diethard's use of an inductively coupled ion source allowed him to systematically study the periodic table of elements with a number of simple neutrals. We have taken the most interesting of these and studied them in greater detail. In doing so, we were able to identify curve crossing rates, in a few instances information about product states, and the importance of multiple entrance channels. [ABSTRACT FROM AUTHOR]

We present initial structural validity evidence for a serious game designed for personnel selection and classification for cybersecurity roles in the US Air Force (USAF). Based on literature review and input from USAF cybersecurity subject‐matter‐experts, we targeted six constructs for assessment. We describe the development process used to build a game to assess individual differences in these constructs, while also being engaging and motivating for players. We attend to the challenge of avoiding an overall game performance factor that dominates variance of multiple constructs scored from the same gameplay episodes and report steps taken to enhance discriminant validity of the scores. We apply factor analysis and item response theory models to develop scores that are reliable, show discriminant validity, and show modest education/gender group differences. Practitioner points: •We developed a serious game to assess six competencies relevant for the US Air Force cyber occupations.•We employed strategies to enhance discrimination validity of the six scores.•We discuss future validation plans for this assessment and implications for design of other serious games. [ABSTRACT FROM AUTHOR]

Wire‐and‐arc additive manufacturing (WAAM) is an innovative technology that involves deposition of subsequent layers of molten materials. Due to the high deposition rates, this technology is suitable for the production of large‐scale complex structures. Further enhancement in the productivity can be achieved by an interlayer cooling strategy that reduces idle time between depositions. However, the effect of the interlayer cooling on microstructure and mechanical properties has to be addressed. In this view, the present work compares microstructural features and mechanical properties of WAAM‐produced plates of austenitic AISI 304 L, focusing on the effect of both active interlayer air cooling and possible anisotropy induced by the additive process. Microstructural and mechanical characterization was conducted on samples extracted along the longitudinal, transverse, and diagonal directions to the deposition layers of WAAM plates, processed with and without interlayer active cooling. Results showed no remarkable influence of cooling conditions on the microstructure and mechanical properties of WAAM plates, which are indeed affected by the anisotropy induced by the additive process. The observed anisotropy in the elastic modulus, independent from different cooling conditions, was related to the crystallographic texture consequent to the highly oriented microstructure typically induced by the process. [ABSTRACT FROM AUTHOR]