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Ideal and practical performance of ram‐jet units in steady flight in the stratosphere at Mach numbers from 1·5 to 4 is examined. The effects of combustion, temperature, altitude, intake and exhaust nozzle design are considered.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

THE graphical methods of one‐dimensional gas dynamics are reviewed and developed to obtain a complete representation of adiabatic flow of perfect gases in ducts of constant cross‐section. The dimensionless charts, from which the variation of the state of the gas along the duct axis can be determined, are analysed and the methods of their construction given. The form of the charts depends only on the value of the ratio of specific heats.

This paper aims to link up the concepts of system bifurcation and system catastrophe with temporal logic in order to show the applicability of dialectical reasoning to metamorphic system transformations. A system catastrophe is an innovation resulting from reorganization resulting from a switch from positive to negative feedback or vice versa. The subsystems would then be oscillators and the truth of any descriptive statement is then distributive. Such oscillations would produce an uncertainty in the temporal trajectory of the system which would increase both towards the past and the future. This means that time is not a scalar dimension, but a quadratic paraboloid distribution of converging and diverging transition probabilities. A social system composed of such oscillators would be heterarchical rather than hierarchical.

When the flow in long pipes is considered, the frictional losses occurring before the pipe entry can usually be neglected. If thus an isentropic flow up to the pipe entry were assumed, the Grashof and Zeuner equation (A. 12) could be represented in the ψ—p plane of the dimensionless de Saint Venant and Wantzel equation (A.23). Using the dimensionless equations of Appendix II, the above plane is developed to cover adiabatic flows in general.

This chapter discusses some issues of diversity in hazard mitigation when just recovery is considered or not. Justice in hazard mitigation becomes crucial considering unequal distribution of resources, systemic racism, and social vulnerability to hazards. While there has been research on just recovery, there is little or no evidence of research that examines the issue of equity and justice in hazard mitigation, This chapter discusses what hazard mitigation is, the Disaster Mitigation Act of 2000 focusing on the planning process, public involvement in the planning process, some planning theories on vulnerability, and building the case for achieving and striving for justice and equity in promoting diversity in hazard mitigation. The chapter makes some recommendation on how to achieve diversity in hazard mitigation.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

The paper discusses the types of singular points occurring in the first‐order ordinary differential equation which describes compressible viscous flow in a channel or stream tube of varying cross‐sectional area. The treatment is one‐dimensional, viscosity being allowed for by assuming a tangential stress acting on the circumference. The resulting patterns of the integral curves arc examined. It is shown that for convergent‐divergent channels whose profile has no point of inflexion, the singular point is a saddle point, as is the case in frictionlcss flow. However, the sonic section or the section of highest or lowest Mach number do not coincide with the throat but arc situated downstream of it in the divergent portion. The slopes of the integral curves which pass through the sonic section arc evaluated. When the convergent‐divergent channel has a point of inflexion in its profile there may be two singular points, the first being a saddle point and the second cither a spiral point or a nodal point. It is shown that spiral points are more likely to occur than nodal points and that, when they occur, there is no radical change in the Mach number variation along the channel due to friction. On the other hand, the existence of a nodal point admits the possibility of a continuous transition from supersonic to subsonic How in which the Mach number at exit may vary within certain limits, the Mach number in the second sonic section remaining always equal to unity. In all types of flow there arc portions of the channel over which the influence of friction outweighs that of area change.

Under this heading are published regularly abstracts of all Reports and Memoranda or the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued