WorldCat Identities

Great Britain Defence Research Agency

Overview
Works: 107 works in 150 publications in 1 language and 226 library holdings
Genres: Conference papers and proceedings  Specifications  Periodicals 
Classifications: G70.4, 621.3678
Publication Timeline
.
Most widely held works about Great Britain
 
moreShow More Titles
fewerShow Fewer Titles
Most widely held works by Great Britain
New views of the earth( Book )

in English and held by 17 WorldCat member libraries worldwide

The DRA table of space vehicles by A. N Winterbottom( Book )

1 edition published in 1993 in English and held by 12 WorldCat member libraries worldwide

Underwater acoustic scattering : an Underwater Acoustics Group Conference held at the Hotel Price Regent, Weymouth, UK, 20th-22nd December 1994 by Institute of Acoustics (Great Britain)( Book )

1 edition published in 1994 in English and held by 5 WorldCat member libraries worldwide

3D pneumatic and 2D dynamic probes : their development and subsequent use in a transonic fan by M. A Cherrett( Book )

2 editions published in 1992 in English and held by 4 WorldCat member libraries worldwide

Three different 3D pneumatic probes have been built and calibrated in detail, along with two dynamic yawmeters and a geometrically identical pneumatic yawmeter. This paper discusses the aerodynamic performance of the probes and compares detailed steady-state flowfield measurements taken with the probes at stator exit in a transonic fan. C148 transonic fan research is supported by the MOD Strategic Research Programme and the Aerospace Division of DTI ... Turbomachinery, Axial flow compressors, Pressure measurement, Unsteady pressure measurement, Viscous flows, C148
The Free decay of coupled heave and pitch motions of a model frigate by P Crossland( Book )

2 editions published in 1992 in English and held by 4 WorldCat member libraries worldwide

The PAT-91 ship program has been found to over predict damping especially at resonant frequencies, resulting in there being no significant peak in the transfer function of pitch at resonance. This memorandum presents the results of a series of experiments that measured the decay time histories of a model frigate free to move in the vertical plane, in an attempt to identify where the problems might be occurring. Judgements are made concerning the components in the heave and pitch motions using the terms in the full two dimensional strip theory heave and pitch motion equations to explain the trends shown. The investigation has shown that the sectional damping coefficient appears to be over predicted. This results in a relatively poor prediction of heave decay curves at low speed and over estimates the damping in the pitch decay curves. It appears that the discrepancies seen in the heave and pitch transfer functions could be due to the wave excitation being predicted incorrectly
The Olympus Satellite Utilisation Programme by J. H Crowther( Book )

2 editions published in 1994 in English and held by 4 WorldCat member libraries worldwide

Sound radiation from infinite laminated composite shell with periodic rib stiffing by J. H James( Book )

3 editions published in 1992 in English and held by 4 WorldCat member libraries worldwide

A theory of sound radiation from an infinite cylindrical shell which is stiffened periodically by ribs is given. Both shell and ribs are laminated composites. The shell is modelled by the differential equations of a thin shell theory. The flexible ribs, which exert both forces and moments on the shell's surface, are modelled by thin conical shell finite elements; degrees of freedom other than those at the shell's surface are removed by receptance methods. Excitations are time-harmonic mechanical forces at arbitrary points on the shell's surface and ribs, and acoustic monopoles in the exterior and interior fluids ... Sound radiation, Composite shell, Fiber reinforced material, Rib stiffening, Theoretical model
Languages for requirements specifications by G. P Randell( Book )

1 edition published in 1992 in English and held by 4 WorldCat member libraries worldwide

This memorandum discusses 11 desirable features that make a requirements specification language a good language. Current languages are assessed to determine which of these features they possess, and where they are lacking. Conclusions are drawn as to the current state of requirements specification languages, and topics for further research are proposed
Report( )

in English and held by 4 WorldCat member libraries worldwide

Annual report & accounts.. by Great Britain( )

in English and held by 3 WorldCat member libraries worldwide

A computer program to calculate growth rates for cracks at notches in regions of residual stress by Rebecca J Cook( Book )

2 editions published in 1992 in English and held by 3 WorldCat member libraries worldwide

This Memorandum describes a computer program which can be used to predict the growth rates of fatigue cracks emanating from notches and growing through residual stress fields. The residual stress distributions, alternating loading conditions and specimen geometry must be specified by the user. The program uses a Green's function technique to calculate the stress intensity factor due to the applied and residual stresses for any crack length. The calculated stress intensity factor can be corrected to account for the exact crack shape, if it is known. The crack growth rate is obtained from a database of experimentally determined crack growth data as a function of stress intensity factor, for a number of different materials ... Fatigue, Crack, Prediction, Program, Fracture mechanics, Residual stress, Cold expansion
The SWORD multilevel secure DBMS by A. W Wood( Book )

1 edition published in 1992 in English and held by 3 WorldCat member libraries worldwide

SWORD is a multilevel secure relational database management system. It adopts the 'Insert Low' approach to the provision of confidentiality controls, rather than the more commonly adopted technique of 'Polyinstantiation'. This allows SWORD to enforce confidentiality and elementary integrity constraints, such as uniqueness. Special techniques allow a multilevel SWORD database to be created and maintained by untrusted database clients working at a single level. In particular, 'Place Holders' allow fields to be created so that the classification of the field's contents dominates the classification of its existence. The report presents an informal description of SWORD and provides a general discussion of the issues. The reader should be familiar with the technical problems of providing multilevel computer security and some understanding of relational databases would be helpful
Acoustic classification and mapping of the seabed : Conference : Papers and abstracts( Book )

1 edition published in 1993 in English and held by 3 WorldCat member libraries worldwide

Electrostatic charging of spacecraft in geosynchronous orbit by Andrew J Sims( Book )

2 editions published in 1992 in English and held by 3 WorldCat member libraries worldwide

This Memorandum is a study of the spacecraft charging phenomenon applicable to satellites in geosynchronous orbit. Differential charging of spacecraft surfaces can induce electrostatic discharges which may manifest themselves as 'operational anomalies' or permanent damage to surface features such as solar cells and thermal control surfaces. Understanding of the problem is achieved via laboratory experiments, analysis of data from spacecraft instrumentation and by numerical simulation. Long-term statistical studies are presented for the location of plasma boundaries at geostationary altitude and for the occurrence frequency and intensity of geomagnetic substorms which permits the probability of severe charging conditions to be predicted for future missions. Laboratory experiments are used to demonstrate the importance of bulk and surface conductivity of dielectric materials to the charging process and a sensitivity analysis is employed to investigate the detailed interaction between the plasma environment and spacecraft surface materials. Finally, a study and simulation of charging events observed in geosynchronous orbit is presented
Intra-blade quantitative transonic flow measurements at the DRA Pyestock isentropic light piston facility using PIV (Particle Image Velocimetry) by K. S Chana( Book )

2 editions published in 1992 in English and held by 3 WorldCat member libraries worldwide

The quantitative whole field flow visualization technique of PIV has over the last three years been successfully demonstrated for transonic flow applications. A series of such measurements has been made at DRA Pyestock. Several of the development stages critical to a full engine application of the work have now been achieved at DRA Pyestock using the Isentropic Light Piston Facility (ILPF) operating with high inlet turbulence levels: - A method of seeding the flow with 0.5 micron diameter styrene particles has provided an even (20 mm by 20 mm) coverage of the flow field. - A method of projecting a 1 mm thick high power Nd/YAG laser light sheet within the turbine stator cascade. This has enabled a complete instantaneous intrablade velocity mapping of the flow field to be visualise. - Finally, software has been developed to automatically analyse the data. The measurements provide an instantaneous quantitative whole field visualization of an unsteady region of flow; which has been compared with a full viscous prediction. This work represents the first such measurements to be made in a transonic annular cascade
The growth of short fatigue cracks in an aluminium alloy by Rebecca J Cook( Book )

2 editions published in 1992 in English and held by 3 WorldCat member libraries worldwide

Fatigue tests have been carried out to establish the effects of various constant amplitude and standardised variable amplitude loading sequences on the growth of short and long cracks in 2024-T3 aluminium alloy. In most cases, the growth rates of short cracks were greater than those of long cracks for the same nominal stress intensity factor ranges, and short cracks grew at stress intensity factor ranges below the long crack threshold values. This Report describes and discusses the experimental crack growth results and compares them with predictions based on the FASTRAN crack closure model of Newman. The experimental work reported includes that which represented the United Kingdom contribution to the core programme of the AGARD cooperative programme on short crack growth behaviour
DRA/NASA/ONERA collaboration on icing research by William B Wright( Book )

3 editions published in 1997 in English and held by 2 WorldCat member libraries worldwide

Blind separation of sources by R. E Bogner( )

2 editions published in 1992 in English and held by 2 WorldCat member libraries worldwide

Electromagnetic scattering from a periodic cylinder by A Baker( )

2 editions published in 1992 in English and held by 2 WorldCat member libraries worldwide

Initial experiments with phoneme decision trees by S. N Downey( )

2 editions published in 1993 in English and held by 2 WorldCat member libraries worldwide

 
moreShow More Titles
fewerShow Fewer Titles
Audience Level
0
Audience Level
1
  Kids General Special  
Audience level: 0.80 (from 0.62 for DRA/NASA/O ... to 1.00 for The Defenc ...)

Alternative Names
Languages
English (44)