Feasibility of obtaining hypervelocity acceleration using propellant lined launch tubes Final report, 27 Sep. 1966 - 5 May 1970

Feasibility of explosive lining in launch tube for hypervelocity projectile acceleratio

A new quantity for studies of dijet azimuthal decorrelations

We introduce a new measurable quantity, $R_{\Delta \phi}$, for studies of the rapidity and transverse momentum dependence of dijet azimuthal decorrelations in hadron-hadron collisions. In pQCD, $R_{\Delta \phi}$ is computed as a ratio of three-jet and dijet cross sections in which the parton distribution functions cancel to a large extent. At the leading order, $R_{\Delta \phi}$ is proportional to $\alpha_s$, and the transverse momentum dependence of can therefore be exploited to determine $\alpha_s$. We compute the NLO pQCD theory predictions and non-perturbative corrections for $R_{\Delta \phi}$ at the LHC and the Tevatron and investigate the corresponding uncertainties. From this, we estimate the theory uncertainties for $\alpha_s$ determinations based on $R_{\Delta \phi}$ at both colliders. The potential of $R_{\Delta \phi}$ measurements for tuning Monte Carlo event generators is also demonstrated.Comment: 20 pages, 11 figures, 1 table, submitted to JHE

Effectiveness of nurse home-visiting for disadvantaged families: results of a natural experiment

Extent: 9p.Objective: To evaluate the effects of a postnatal home-visiting programme delivered by community health nurses to socially disadvantaged mothers in South Australia. Design: The intervention group of 428 mothers lived in metropolitan Adelaide and the comparison group of 239 mothers lived in regional towns where the programme was not yet available. All participating mothers met health service eligibility criteria for enrolment in the home-visiting programme. Participants in both groups were assessed at baseline (mean child age=14.4 weeks SD=2.3), prior to programme enrolment, and again when the children were aged 9, 18 and 24 months. Setting: State-wide community child health service. Participants: 667 socially disadvantaged mothers enrolled consecutively. 487 mothers (73%) completed the 24-month assessment. Intervention: Two-year postnatal home-visiting programme based on the Family Partnership Model. Primary outcome measures: Parent Stress Index (PSI), Kessler Psychological Distress Scale and the Ages and Stages Questionnaire. Results: Mixed models adjusting for baseline differences were used to compare outcomes in the two groups. The mothers in the home-visiting group reported greater improvement on the PSI subscales assessing a mother's perceptions on the quality of their relationship with their child (1.10, 95% CI 0.06 to 2.14) and satisfaction with their role as parents (0.46, 95% CI −0.15 to 1.07) than mothers in the comparison group. With the exception of childhood sleeping problems, there were no other significant differences in the outcomes across the two groups. Conclusions: The findings suggest that home-visiting programmes delivered by community health nurses as part of routine clinical practice have the potential to improve maternal–child relationships and help mothers adjust to their role as parents.Michael Gifford Sawyer, Linda Frost, Kerrie Bowering, John Lync

Inclusion of explicit thermal requirements in optimum structural design

A finite-element based procedure is described for obtaining minimum mass designs of structures subjected to combined thermal and mechanical loading and both strength and thermal constraints. The procedure is based on a mathematical programming method using the Sequence of Unconstrained Minimizations Technique (SUMT) in which design requirements are incorporated by an exterior penalty function. The procedure is limited to steady-state temperatures which are controlled by structural sizing only. The optimization procedure is demonstrated by the design of a structural wing box with both mechanical loading and external heating, subject to design constraints on stress, minimum gage, and temperature. The final design for these conditions is compared with a corresponding design in which temperature constraints are omitted

External store effects on the stability of fighter and interceptor airplanes

Some criteria for external carriage of missiles for fighter aircraft intended for aerial combat missions and for fighter-interceptor missions are considered. The mission requirements discussed include the short-range fighter-interceptor, the short-range interceptor, the medium-range interceptor, and the long-range interceptor. Missiles types considered to be compatible with the various point mission designs include the short-range missile, the medium-range missile, and the long-range missile. From the study, it appears that point mission design aircraft can be arranged in such a way that the required external-store arrangement will not impair the stability of the aircraft. An extensive reference list of NASA external store research is included

A computer graphics program for general finite element analyses

Documentation for a computer graphics program for displays from general finite element analyses is presented. A general description of display options and detailed user instructions are given. Several plots made in structural, thermal and fluid finite element analyses are included to illustrate program options. Sample data files are given to illustrate use of the program

Simulation studies of STOL airplane operations in metropolitan downtown and airport air traffic control environments

The operating problems and equipment requirements for STOL airplanes in terminal area operations in simulated air traffic control (ATC) environments were studied. These studies consisted of Instrument Flight Rules (IFR) arrivals and departures in the New York area to and from a downtown STOL port, STOL runways at John F. Kennedy International Airport, or STOL runways at a hypothetical international airport. The studies were accomplished in real time by using a STOL airplane flight simulator. An experimental powered lift STOL airplane and two in-service airplanes having high aerodynamic lift (i.e., STOL) capability were used in the simulations

Terminal-area flight procedures and route design for supersonic transport New York-transatlantic operations

The results of an analytical investigation of two departure and arrival transition procedures between John F. Kennedy International Airport and projected North Atlantic track systems for supersonic transport (SST) operations are presented. The procedures studied were: (1) separated departure and arrival transition routes with departures made at supersonic speeds, and (2) superimposed departure and arrival routes with departures restricted to subsonic speed until the airplane is on the track system. For both procedures, transition routes with intercept angles of 30 deg to 90 deg to both six-and four-track systems were investigated. Track spacings of 30 and 60 nautical miles were studied