Boeing (Canada)

BACKGROUND: Operating-room crises (e.g., cardiac arrest and massive hemorrhage) are common events in large hospitals but can be rare for individual clinicians. Successful management is difficult and complex. We sought to evaluate a tool to improve adherence to evidence-based best practices during such events. METHODS: Operating-room teams from three institutions (one academic medical center and two community hospitals) participated in a series of surgical-crisis scenarios in a simulated operating room. Each team was randomly assigned to manage half the scenarios with a set of crisis checklists and the remaining scenarios from memory alone. The primary outcome measure was failure to adhere to critical processes of care. Participants were also surveyed regarding their perceptions of the usefulness and clinical relevance of the checklists. RESULTS: A total of 17 operating-room teams participated in 106 simulated surgical-crisis scenarios. Failure to adhere to lifesaving processes of care was less common during simulations when checklists were available (6% of steps missed when checklists were available vs. 23% when they were unavailable, P<0.001). The results were similar in a multivariate model that accounted for clustering within teams, with adjustment for institution, scenario, and learning and fatigue effects (adjusted relative risk, 0.28; 95% confidence interval, 0.18 to 0.42; P<0.001). Every team performed better when the crisis checklists were available than when they were not. A total of 97% of the participants reported that if one of these crises occurred while they were undergoing an operation, they would want the checklist used. CONCLUSIONS: In a high-fidelity simulation study, checklist use was associated with significant improvement in the management of operating-room crises. These findings suggest that checklists for use during operating-room crises have the potential to improve surgical care. (Funded by the Agency for Healthcare Research and Quality.).

With a transverse array of channels of equal widths but differing resistances, we have generated an improved approximation to spatially homogeneous turbulent shear flow. The scales continue to grow with downstream distance, even in a region where the mean velocity gradient and one-point turbulence moments (component energies and shear stress) have attained essentially constant values. This implies asymptotic non-stationarity in the basic Eulerian frame convected with the mean flow, behaviour which seems to be inherent to homogeneous turbulent shear flow. Two-point velocity correlations with space separation and with space-time separation yield characteristic departures from isotropy, including clear ‘upstream–downstream’ unsymmetries which cannot be classified simply as axis tilting of ellipse-like iso-correlation contours. The high wave-number structure is roughly locally isotropic although the turbulence Reynolds number based on Taylor ‘microscale’ and r.m.s. turbulent velocity is only 130. Departures from isotropy in the turbulent velocity gradient moments are measurable. The approximation to homogeneity permits direct estimation of all components of the turbulent pressure/velocity-gradient tensor, which accounts for inter-component energy transfer and helps to regulate the turbulent shear stress. It is found that its principal axes are aligned with those of the Reynolds stress tensor. Finally, the Rotta (1951, 1962) linear hypothesis for intercomponent energy transfer rate is roughly confirmed.

Abstract A statistical model for life-lengths of structures under dynamic loading is derived. The model makes it possible to express the probability distribution of life-lengths in terms of the load given as a function of time and of deterioration occurring in time independently of loading. The special case of a constant load (or of periodic loading with constant amplitude) leads to gamma distributions for life lengths.

Summary Results of an experimental investigation of the distribution of skin friction along the wall of a plane turbulent wall jet are presented. The measurements show that it is possible to describe the variation of skin friction coefficient by a formula similar to the Blasius formula which is based on experimental results of turbulent pipe flow. This is simply achieved by considering the inner layer of fluid between the wall and the position where the velocity is a maximum as a boundary layer with an outer uniform free stream of velocity equal to the local maximum velocity. Other measurements of velocity distribution indicate that within the experimental range and accuracy, the velocity profiles in the jet are similar and that the rate of change of velocity and width of the jet can be expressed by simple power laws. These results are then partially compared with theory.

MBE-grown GAN/AlGaN HEMTs have been fabricated on a 2" SiC wafer, where the source-drain spacing was 2 µm and the gate length was 0.15 µm. A peak extrinsic transconductance of 350 mS/mm and a maximum drain current density greater than 1.5 A/mm were obtained. Small-signal S-parameter measurement showed fT of 85 GHz and fMAX approaching 140 GHz. At 20 GHz, a continuous-wave output power density of 6.6 W/mm was obtained with power-added-efficiency (PAE) of 35%, yielding the highest reported power performance at 20 GHz.

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;This paper summarizes the recent development of an adaptive aeroelastic wing shaping control technology called variable camber continuous trailing edge flap (VCCTEF). As wing flexibility increases, aeroelastic interactions with aerodynamic forces and moments become an increasingly important consideration in aircraft design and aerodynamic performance. Furthermore, aeroelastic interactions with flight dynamics can result in issues with vehicle stability and control. The initial VCCTEF concept was developed in 2010 by NASA under a NASA Innovation Fund study entitled “Elastically Shaped Future Air Vehicle Concept,” which showed that highly flexible wing aerodynamic surfaces can be elastically shaped in-flight by active control of wing twist and bending deflection in order to optimize the spanwise lift distribution for drag reduction. A collaboration between NASA and Boeing Research &amp;amp; Technology was subsequently funded by NASA from 2012 to 2014 to further develop the VCCTEF concept.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;This paper summarizes some of the key research areas conducted by NASA during the collaboration with Boeing Research and Technology. These research areas include VCCTEF design concepts, aerodynamic analysis of VCCTEF camber shapes, aerodynamic optimization of lift distribution for drag minimization, wind tunnel test results for cruise and high- lift configurations, flutter analysis and suppression control of flexible wing aircraft, and multi-objective flight control for adaptive aeroelastic wing shaping control.&lt;/div&gt;&lt;/div&gt;

It was established in (5) that the existence of a Hadamard matrix of order 4 t is equivalent to the existence of a symmetrical balanced incomplete block design with parameters v = 4 t — 1, k = 2 t — 1, and λ = t — 1. A block design is completely characterized by its so-called incidence matrix. The existence of a block design with parameters v , k , and λ such that the corresponding incidence matrix is cyclic was shown in (3) to be equivalent to the existence of a cyclic difference set with parameters v , k , and λ. For certain values of the parameters, Hadamard matrices, block designs, and difference sets do coexist.

&lt;div class="htmlview paragraph"&gt;This paper describes a numerical method for solving three-dimensional incompressible flow problems and its use in predicting the aerodynamic characteristics of V/STOL aircraft. Arbitrary configuration and inlet geometry, fan inflow distributions, thrust vectoring, jet entrainment, angles of yaw, and flight speeds from hover through transition can be treated. Potential-flow solutions are obtained with the method of influence coefficients, using source and doublet panels distributed on the boundary surfaces. The results include pressure distributions, lift, induced drag and side force, and moments. Theoretical solutions are presented for clean lifting wings and for a NASA fan-in-wing model. Comparisons with the experimental NASA data demonstrate the validity of the approach and uncover the importance of viscous effects, fan inflow distribution, and jet entrainment.&lt;/div&gt;

Luminescent sensors based on composites comprising transition metal complexes immobilized in polymer matrices have attracted attention as oxygen sensors for both biomedical and barometric applications. Typically, phosphorescent dyes are dispersed in a polymer matrix of high gas permeability are used. Here, S–N–P polymers are used as a novel matrix material allowing the sensitivity of the sensors to be controlled over a wide range.

The Spalart-Allmaras one-equation turbulence model and the Menter two-equation turbulence model are assessed for Navier-Stokes computations of high-lift aerodynamic flows, including cases with significant regions of separated flow. Cases considered include 1) separated flow over a single-element airfoil at high lift, 2) fully attached flows over the NLR 7301 airfoil and flap, and 3) separated flow over the GA(W)-1 airfoil and flap. For the single-element case, the Menter model provides better agreement with the experimental pressure distribution and velocity profiles. For the NLR 7301 airfoil and flap, both turbulence models provide excellent agreement with experimental pressures and skin-friction data. Velocity profiles are generally well predicted except in some parts of wakes. Turbulent shear stresses are not always well predicted. The predictions of the Spalart-Allmaras model are generally superior for this case, especially when boundary-layer confluence is important.

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A statistical model for life-lengths of structures under dynamic loading is derived. The model makes it possible to express the probability distribution of life-lengths in terms of the load given as a function of time and of deterioration occurring in time independently of loading. The special case of a constant load (or of periodic loading with constant amplitude) leads to gamma distributions for life lengths.

This paper presents the results of a comprehensive experimental study, mainly using square panels, of a recently introduced high-strength aluminum alloy sheet material and its resistance to the propagation of fatigue cracks. An axial-load fatigue machine, applying both constant and Rayleigh random loads, was developed for the test program, and fatigue cracks in the panels were continuously monitored by a new servo-controlled eddy-current crack follower. The resulting traces of crack length permitted the study of several crack growth laws, by manipulation of the loads to maintain a theoretically constant crack growth rate. From the tests where the load levels were not altered, an optimum thickness of sheet (yielding a minimum average crack growth rate) was indicated. Load-shedding, a phenomenon inherent in the failure of elements in redundant (fail-safe) structures, was simulated in many of the tests. It was found that appreciably different load-shedding histories still yielded the same instantaneous crack growth rate for a given instantaneous level of stress intensity factor. It was found that fracture mechanics provided the most effective approach for the study of fatigue crack propagation, either by constant amplitude or by Rayleigh random amplitude loading.

BACKGROUND: Formal thought disorder is a cardinal feature of psychosis. However, the extent to which formal thought disorder is evident in ultra-high-risk individuals and whether it is linked to the progression to psychosis remains unclear. AIMS: Examine the severity of formal thought disorder in ultra-high-risk participants and its association with future psychosis. METHOD: The Thought and Language Index (TLI) was used to assess 24 ultra-high-risk participants, 16 people with first-episode psychosis and 13 healthy controls. Ultra-high-risk individuals were followed up for a mean duration of 7 years (s.d.=1.5) to determine the relationship between formal thought disorder at baseline and transition to psychosis. RESULTS: =0.04; ES=1.04). CONCLUSIONS: TLI is beneficial in evaluating formal thought disorder in ultra-high-risk participants, and complements existing instruments for the evaluation of psychopathology in this group. DECLARATION OF INTERESTS: None. COPYRIGHT AND USAGE: © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.

Abstract Fracture repair is characterized by cytokine production and hypoxia. To better predict cytokine modulation of mesenchymal stem cell (MSC)‐aided bone healing, we investigated whether interleukin 4 (IL‐4), IL‐6, and their combination, affect osteogenic differentiation, vascular endothelial growth factor (VEGF) production, and/or mammalian target of rapamycin complex 1 (mTORC1) activation by MSCs under normoxia or hypoxia. Human adipose stem cells (hASCs) were cultured with IL‐4, IL‐6, or their combination for 3 days under normoxia (20% O 2 ) or hypoxia (1% O 2 ), followed by 11 days without cytokines under normoxia or hypoxia. Hypoxia did not alter IL‐4 or IL‐6‐modulated gene or protein expression by hASCs. IL‐4 alone decreased runt‐related transcription factor 2 (RUNX2) and collagen type 1 (COL1) gene expression, alkaline phosphatase (ALP) activity, and VEGF protein production by hASCs under normoxia and hypoxia, and decreased mineralization of hASCs under hypoxia. In contrast, IL‐6 increased mineralization of hASCs under normoxia, and enhanced RUNX2 gene expression under normoxia and hypoxia. Neither IL‐4 nor IL‐6 affected phosphorylation of the mTORC1 effector protein P70S6K. IL‐4 combined with IL‐6 diminished the inhibitory effect of IL‐4 on ALP activity, bone nodule formation, and VEGF production, and decreased RUNX2 and COL1 expression, similar to IL‐4 alone, under normoxia and hypoxia. In conclusion, IL‐4 alone, but not in combination with IL‐6, inhibits osteogenic differentiation and angiogenic stimulation potential of hASCs under normoxia and hypoxia, likely through pathways other than mTORC1. These results indicate that cytokines may differentially affect bone healing and regeneration when applied in isolation or in combination.

A correction method is described for half-model tests using wall pressures measured by longitudinal static pressure tubes and measured model forces. The Dirichlet problem for the Mach number correction is solved by a doublet-panel method and the flow angle corrections are obtained from the irrotational flow conditions. The method is applied to a transport aircraft half-model tested in the NAE perforated-wall wind tunnel. The Mach number and angle-of-attack corrections are presented as contour plots, allowing analysis of the effects of wallinduced gradients. In the range of normal operating lift coefficients, the corrected drag polar is shown to correlate well with data from full-model wind-tunnel tests and from the flight test aircraft.

Note presenting a method for computing the steady-state span load distribution on an elastic airplane wing for specified airplane weights and load factors. The method is based on a modification of the Weissinger L-method and applies at subcritical Mach numbers.

A variational principle due to E. Reissner has been rewritten in a form which is applicable to small deflection problems for thin plates. The modified principle is used to obtain approximations to static deflection and vibration problems of square and skew cantilever plates of uniform thickness.

Abstract Concurrent Engineering aims to incorporate the overlapping of processes in order to reduce its time-to-market and thereby sustain the existence of organizations in increasingly competitive times. Although faster product design, development, and delivery are the intended outcomes of concurrent engineering, one of the undesirable by-products is an increase in risks as a consequence of uncertainties between interdependent processes. Hence, the risks need to be identified, assessed, and mitigated together with concurrent engineering considerations for the elimination of the ‘domino-effect’ within risk management. This paper concentrates primarily on knowledge elicitation techniques that were used to provide information to the Intelligent Risk Mapping and Assessment System (IRMAS™) to identify, prioritise, analyse, and assist project managers to manage perceived sources of CE risks. Techniques such as expert interviews, brainstorming, the Delphi technique, and the analogy process are discussed in relation to compiling the knowledge used for this expert system. A total of 589 risk items were identified for different project types, and information on 4372 items and 136 lessons learned were collected from experts at HdH. The core of the research is a reasoning methodology used for Knowledge Elicitation of a Risk Mapping and Assessment System which will not only support the decision-making process of the user but also aid the knowledge retrieval, storage, sharing, and updating process of manufacturing organizations. This research provides a systematic engineering approach to risk management of concurrent product and process development. Keywords: Knowledge elicitationRisk mappingEngineering projects Acknowledgements The authors would like to acknowledge the invaluable contributions of M. Zhou, Y.B. Khoo, A. Ahmed, and R. Kusumo during the system development, validation, and implementation of IRMAS™. This research was funded by the Cooperative Research Centre for Intelligent Manufacturing Systems and Technologies (CRC-IMST) Australia under the subprogramme 4.2. The authors also acknowledge our Industrial partner, Hawker de Havilland–Boeing, for contributions in the conduct of this research.

Abstract A singular finite element is developed for direct calculation of combined modes I and II stress intensity factors for planar rectilinear anisotropic structures subject to arbitrary loading. Twelve‐node conventional elements are used in conjunction with a linear elastic fracture mechanics enrichment of the same element which is formed into a four‐element macro‐element. Example problems show this formulation to be exceptionally accurate and results are presented for a variety of modern fibre‐reinforced composites in simple mode I extension and in mixed mode I and II situations. In addition, it is shown that the meshes for accurate results are relatively coarse and thus calculations are quite economical.