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© 2017 Elsevier Ltd Objectives to examine evidence of women's, labour companions’ and health professionals’ experiences of management of early labour to consider how this could be enhanced to better reflect women's needs. Design a systematic review of qualitative evidence. Setting and participants women in early labour with term, low risk singleton pregnancies, not booked for a planned caesarean birth or post-dates induction of labour, their labour companions, and health professionals responsible for early labour care (e.g. midwives, nurse-midwives, obstetricians, family doctors). Studies from high and middle income country settings were considered. Findings 21 publications were included from the UK, Ireland, Scandinavia, USA, Italy and New Zealand. Key findings included the impact of communication with health professionals (most usually midwives) on women's decision making; women wanting to be listened to by sympathetic midwives who could reassure that symptoms and signs of early labour were ‘normal’ and offer clear advice on what to do. Antenatal preparation which included realistic information on what to expect when labour commenced was important and appreciated by women and labour companions. Views of the optimal place for women to remain and allow early labour to progress differed and the perceived benefit of support and help offered by labour companions varied. Some were supportive and helped women to relax, while others were anxious and encouraged women to seek early admission to the planned place of birth. Web-based sources of information are increasingly used by women, with mixed views of the value of information accessed. Key conclusions and implications for practice women, labour companions and health professionals find early labour difficult to manage well, with women unsure of how decisions about admission to their planned place of birth are taken. It is unclear why women are effectively left to manage this aspect of their labour with minimal guidance o

This paper highlights the role of the model in the overall wind tunnel test program. Depending on the specific task to be achieved (i.e. improvement of an existing missile or a new missile development), the cost-effectiveness analysis leads to the best solution in terms of: scale of the model; number of configurations to be tested; degree of likelihood; wind tunnel facilities to be used; interoperability among different test sites; overall test time; test time of each subphase. Defining a missile, one of the main fields of investigation regards the determination of the aerodynamic data. (JES), This article is from 'Stability and Control of Tactical Missile Systems', AD-A218 094, p18-1 thru p18-10.

This paper deals with the problem of controlling static unstable airframes of tactical missiles through the proper choice both of gains and of the autopilot configuration. Unlike other excellent treatments of the subject, the paper tries to simplify to the extreme the analytical description of the problem in order to shorten the gap between the aerodynamicist and the control system designer. Classical feedback paths are described highlighting the key features of each of them and a method of direct synthesis is presented valid for both stable and unstable airframes. The maximum allowable instability of the airframe is derived. The problem of controlling unstable airframes is not new or unusual. This requirement was dictated in the past by the need to accommodate an acceptable trade off to the center of gravity excursions during the boost phase and to compensate for the center of pressure shifts throughout all the flight situations encountered by the missile during its mission. (JES), This article is from 'Stability and Control of Tactical Missile Systems', AD-A218 094, p13-1 thru p13-18.

This paper describes an analytical method developed with the purpose to compare the kinematic and dynamic performance of a winged configuration with respect to a wingless configuration of a tactical anti-air missile. a reference mission of the missile is firstly defined and the analytical method is built-up through the introduction of suitable assumptions and simplifications. The method is then applied to an actual missile for which wind tunnel results are available in its winged and wingless configuration. (jes), This article is from 'Stability and Control of Tactical Missile Systems', AD-A218 094, p28-1 thru p28-20.

This paper describes, from the begin to the end, the development process of the new aerodynamic version of the Aspide in the surface to air role. The aims, constraints and main activities of the project are reported. The entire decision process is also analyzed in great detail. The successful completion of the above process, with the new configuration in full production constitutes the solid background for further improvements or new designs. Keywords: Guided missile. (JES), This article is from 'Stability and Control of Tactical Missile Systems', AD-A218 094, p27-1 thru p27-10.

The results of microwave attenuation, phase shift and radiation temperature measurements in the late afterglows of pulsed oxygen discharges of various types are discussed from the point of view of the collision frequency and G-factor determination. A new general theory for the evaluation of the G- factor from the radiation temperature increases under microwave heating conditions is reported. The values computed with this theory in nitrogen are in very good agreement with the previous diffusion measurements by Crompton and Sutton, whereas in oxygen the agreement with the measurements by Healey and Kirkpatrick is much less satisfactory.

The propagation characteristics of a uniform magnets-ionic duct of circular cross-section are determined for frequencies higher than the cyclotron frequency - The ratios: plasma wavelength/free space wavelength and power flowing in the plasma/power flowing outside are evaluated and discussed as a function of the diameter/wavelength ratio and of the plasma permittivity for the propagation of circularly symmetrical modes. The Brillouin diagrams for frequencies higher and lower than the cyclotron frequency are also derived.

Starting from Maxwell's equations, a general investigation of the propagation of a quasistatic E mode in a plasma column with non uniform electron density distribution in the cross-section, is considered, where a parabolic distribution has been taken as an analytical model for the electron density profile in the cross-section. Electron density is supposed to vanish at a point outside the plasma column; in the limit for the zero point to go to infinity, uniform case equations are obtained. Letting the metal walls move to infinity, or coincide with the plasma boundary, the completely filled wave guide and the plasma column in free space dis persion curves have been verified. The Ritz variational method is used to minimize the error over the cross section when an approxi mation function for the field distribution in the plasma is assumed., Trans. from Societa' Selenia via Tiburtina KM 12:4, S.p.A. Roma.

A description is presented of the theoretical and experimental work performed on the propagation of electromagnetic waves along plasma columns in logitudinal magnetic fields. Theoretical work includes: completion of the basic theory for propagation along plasma columns in magnetic fields; derivation of Brillouin diagrams; and discussion of particularly significant limits and preliminary analyses of the non-uniform plasma case. Experimental work includes: measurements of basic propagation parameters; transmitted signal; wavelength and group velocity; and of physical plasma parameters as the electron density.

The problem of elimination of the velocity measurement ambiguities (arising in systems using pulsed signals), by means of a variable repetition rate was investigated both theoretically and experimentally. The practical interest of such a method was ascertained and some basic considerations were made on the fundamental aspects of the problem. The experimental results, in terms of a measured line spectrum, are in good agreement with the values given by the theory, evaluated with the help of a digital computer. (Author)

The work performed under this Contract is described. Theoretical work includes: discussion of the basic quasi-static and exact theories for propagation along plasma slabs and columns in magnetic fields, derivation of Brillouin diagrams, calculations of electromagnetic power flows, extension of theory to the case of external metallic walls, comparison with whistlertype characteristics, approximate evaluations of propagation features in non-uniform and in warm plasma slabs. Experimental work includes: detection of plasma guided signals, measurements of their amplitudes, phase and group velocities, check measurements of the electron density. Most of the experimental results are interpreted in terms of the discussed theory. (Author)