Wind-tunnel investigation of aerodynamic loading on a 0.237-scale model of a remotely piloted research vehicle with a thick, high-aspect-ratio supercritical wing

Wind-tunnel measurements were made of the wing-surface static-pressure distributions on a 0.237 scale model of a remotely piloted research vehicle equipped with a thick, high-aspect-ratio supercritical wing. Data are presented for two model configurations (with and without a ventral pod) at Mach numbers from 0.70 to 0.92 at angles of attack from -4 deg to 8 deg. Large variations of wing-surface local pressure distributions were developed; however, the characteristic supercritical-wing pressure distribution occurred near the design condition of 0.80 Mach number and 2 deg angle of attack. The significant variations of the local pressure distributions indicated pronounced shock-wave movements that were highly sensitive to angle of attack and Mach number. The effect of the vertical pod varied with test conditions; however at the higher Mach numbers, the effects on wing flow characteristics were significant at semispan stations as far outboard as 0.815. There were large variations of the wing loading in the range of test conditions, both model configurations exhibited a well-defined peak value of normal-force coefficient at the cruise angle of attack (2 deg) and Mach number (0.80)

The Role of Cold Flows in the Assembly of Galaxy Disks

We use high resolution cosmological hydrodynamical simulations to demonstrate that cold flow gas accretion, particularly along filaments, modifies the standard picture of gas accretion and cooling onto galaxy disks. In the standard picture, all gas is initially heated to the virial temperature of the galaxy as it enters the virial radius. Low mass galaxies are instead dominated by accretion of gas that stays well below the virial temperature, and even when a hot halo is able to develop in more massive galaxies there exist dense filaments that penetrate inside of the virial radius and deliver cold gas to the central galaxy. For galaxies up to ~L*, this cold accretion gas is responsible for the star formation in the disk at all times to the present. Even for galaxies at higher masses, cold flows dominate the growth of the disk at early times. Within this modified picture, galaxies are able to accrete a large mass of cold gas, with lower initial gas temperatures leading to shorter cooling times to reach the disk. Although star formation in the disk is mitigated by supernovae feedback, the short cooling times allow for the growth of stellar disks at higher redshifts than predicted by the standard model.Comment: accepted to Ap

Artificial intelligence in the legal sector: pressures and challenges of transformation

Recent technological developments in automation and Artificial Intelligence (AI) promise to disrupt the very foundations of how legal work is practised and delivered. Yet how they challenge current business models, where they encounter resistance, and how the benefits of AI can be realised remain unexplored. Drawing on interviews with professionals in the UK legal services sector, the paper highlights how technological and market pressures combine to challenge the business models of legal services firms. However, the findings reveal important cultural and structural challenges that hamper transformation. The paper extends the debate on technological disruption in legal services through a focus on business model innovation as a tool that can support firms in the sector to reimagine legal service provision

The “additional costs” of being peripheral: developing a contextual understanding of micro-business growth constraints

Purpose Despite their economic significance, empirical evidence on the growth constraints facing micro-businesses as an important subset of small and medium enterprises remains scarce. At the same time, little consideration has hitherto been given to the context in which entrepreneurial activity occurs. The purpose of this paper is to develop an empirically informed contextual understanding of micro-business growth, beyond firm-level constraints. Design/methodology/approach The paper draws on 50 in-depth interviews with stakeholders and micro-business owner–manager entrepreneurs (OMEs henceforth) in a peripheral post-industrial place (PPIP henceforth). Findings The paper shows that, beyond firm-level constraints generated by their OME-centric nature, there are “additional costs” for micro-businesses operating in PPIPs, specifically limited access to higher-skilled labour, a more challenging, “closed” business environment and negative outward perceptions stemming from place stigmatisation. All of these “additional costs” can serve to stymie OMEs' growth ambition. Research limitations/implications The paper is based on a limited number of interviews conducted in one region in England. However, the contextualisation of the findings through a focus on PPIPs provides valuable insights and enables analytical generalisation. Originality/value The article develops a context-sensitive model of micro-business growth constraints, one that goes beyond the constraints inherent in the nature of micro-businesses and is sensitive to their local (socio-institutional) operating context. The implications serve to advance both how enterprise in the periphery is theorised and how it is addressed by policymakers and business intermediaries to support the growth of micro-businesses

Advances in Moire interferometry for thermal response of composites

An experimental technique for the precise measurement of the thermal response of both sides of a laminated composite coupon specimen uses Moire interferometry with fringe multiplication which yields a sensitivity of 833 nm (32.8 micro in.) per fringe. The reference gratings used are virtual gratings and are formed by partially mirrorized glass prisms in close proximity to the specimen. Results are compared with both results obtained from tests which used Moire interferometry on one side of composite laminates, and with those predicted by classical lamination theory. The technique is shown to be capable of producing the sensitivity and accuracy necessary to measure a wide range of thermal responses and to detect small side to side variations in the measured response. Tests were conducted on four laminate configurations of T300/5208 graphite epoxy over a temperature range of 297 K (75 F) to 422 K (300 F). The technique presented allows for the generation of reference gratings for temperature regimes well outside that used in these tests

Magnetic-Moment Fragmentation and Monopole Crystallization

The Coulomb phase, with its dipolar correlations and pinch-point-scattering patterns, is central to discussions of geometrically frustrated systems, from water ice to binary and mixed-valence alloys, as well as numerous examples of frustrated magnets. The emergent Coulomb phase of lattice-based systems has been associated with divergence-free fields and the absence of long-range order. Here, we go beyond this paradigm, demonstrating that a Coulomb phase can emerge naturally as a persistent fluctuating background in an otherwise ordered system. To explain this behavior, we introduce the concept of the fragmentation of the field of magnetic moments into two parts, one giving rise to a magnetic monopole crystal, the other a magnetic fluid with all the characteristics of an emergent Coulomb phase. Our theory is backed up by numerical simulations, and we discuss its importance with regard to the interpretation of a number of experimental results

Management of Mechanical Ventilation in Decompensated Heart Failure.

Mechanical ventilation (MV) is a life-saving intervention for respiratory failure, including decompensated congestive heart failure. MV can reduce ventricular preload and afterload, decrease extra-vascular lung water, and decrease the work of breathing in heart failure. The advantages of positive pressure ventilation must be balanced with potential harm from MV: volutrauma, hyperoxia-induced injury, and difficulty assessing readiness for liberation. In this review, we will focus on cardiac, pulmonary, and broader effects of MV on patients with decompensated HF, focusing on practical considerations for management and supporting evidence

Teacher education policy making during the pandemic: shifting values underpinning change in England?

This paper examines how the policy process around initial teacher education (ITE) during the pandemic of 2020 was experienced by the leaders of ITE programmes across England.Education policies,it is argued, are solutions to perceived problems, revealing latent values that drive action. Group interviews with leaders of ITE programmes across the education sector, focused on the lived experience of ITE policy developments during the first wave of the COVID-19 period (March to July 2020). The analysis drew upon three policy drivers derived from an examination of teacher education policy (prior to the pandemic) in four ‘high performing’ English-speaking countries (according to PISA). The three policy drivers: the economy and global competitiveness (the rationale for change); accountability and regulatory framework (the technologies for change); and the core purpose of schooling and teacher professionalism (the values underpinning change); show how the temporary policy shift soon reverted back to previous priorities. Agency and autonomy were experienced by teacher educators which enabled them to exercise expert judgment, but there were also the significant ‘gaps’ in the expertise of policymakers. The research reveals how values influences policy formation, creating divisions within England’s ITE community, and isolating it from international policy trends

James River slack water data report : temperature, salinity, dissolved oxygen, 1971 - 1980

The slack water survey program, which has been supp orted by the State Water Control Board and the Virginia Institute of Marine Science under the Cooperative State Agencies program, provides an extended series of tem perature, salinity, dissolved oxygen and nutrient measurements along the James River. These have been used to: 1) establish, verify, and update mathe matical and physical hydraulic models; 2) provide a baseline against which effects of unusual events have been measured; and could be used to: 3) es tablish annu al and longer period 11 climatological trends in response to changing natural phenomena and man-made modifica tions to the estuary; 4) provide a basis against which fluctuations in biota could be compared. This report contains station locations, survey schedules, field procedures, sample handling procedures, and data reduction and storage procedures. In addition, 10 years of contoured temperature, salinity, and dissolved oxygen data is presented. The primary purpose of this report is to provide the data in a format which we believe will be useful to others. Analysis and interpretation of the data is underway and this will be the subject of a later report