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The European Space Agency's campaign, RENE'91, for the geophysical calibration and validation of its ERS-1 satellite took place in the Haltenbanken area of the Norwegian Sea in the Autumn of 1991. A primary objective was to collocate surface wind measurements over the sea with normalized radar cross section (0) measurements from the ERS-1 Scatterometer, in order to establish a radar sea-echo model from space derived data. The scatterometer's three-beam 0 products from 77 orbits were merged with 10 metre height, neutral stability, wind vector estimates from a field analysis program which combined aircraft, buoy, ship, and meteorological background field measurements. To provide enough data to study 0 against the main physical variables, raw 0 values were classified (binned) into ranges of incidence angle (), wind speed (v), and wind direction with respect to the scatterometer beam (), and a bin average 0 calculated for used in subsequent analysis. A by-product was lower noise and data volume. The Haltenban...

Summary form only given. A versatile instrument for use in ventilated animals that allows synchronization of high-frequency jet ventilation with specific moments in the cardiac cycle is described. The instrument may be triggered either internally or externally from the electrocardiogram or dP/dt signal. The instrument is compact and easy to operate, meets BS5724 requirements for patient-connected equipment, and provides continuous jet ventilation in the absence of stable hemodynamics. >

The design, construction, and testing of a system for the induction of coronary artery stenosis in large animals is discussed. Readily available stepping linear actuators are used, and the instrument allows monitoring and digital display of both cuff pressure and arterial pressure. The system is described together with results of in vivo testing. >

During the Engineering Design Activity (EDA) of the ITER program a major effort is being devoted to conductor R&D for the ITER magnets systems. This program includes all aspects of cable-in-conduit-conductor (CICC) manufacturing development such as superconducting strand, large multistage cables, and fabrication of thick-wall and thin-wall conduits. It also includes an extensive program of small scale laboratory measurements and experiments designed to predict the full-size conductor and magnet performance, and to quantify elements of the conductor design guidelines. A description of the manufacturing development and experimental program is given, including experiments for determining AC losses in the superconductor, CICC stability under BC and fast ramped conditions of field and current, and development of novel quench detection techniques.

The determination of the optimum electrical parameters of a spherical electric field gas scintillation spectrometer for X-ray astronomy is described. Detailed measurements using a collimated 55Fe 5.9 keV X-ray source are presented leading to trade-offs of drift field, shaping and scintillation field in an endeavour to provide a uniform response in terms of energy and time resolution over the full aperture of 314 cm2. The optimized uncollimated energy resolution at 6 and 60 keV was 11.0 and 4.5% fwhm respectively. The total background rejection efficiency for 60Co gamma ray induced events was 97 and 70% in the energy range 1–10 and 1–60 keV respectively. Finally design improvements which yield and energy resolution as low as 7.5%K at 6 keV are outlined.

Scaled models have been used in an experimental investigation of the punching capacity and moment transfer characteristics of typical flat slab edge column connections. One of the main aims was to examine the influence of, and attempt to relate, the location of the slab free edge to the column punching capacity. The punching loads of the various joints were found to be in excess of those predicted by both C.P. 110 and A.C.I. 318-77. In addition, the tests showed that the moments transferred from the slab to the columns could be closely predicted by the A.C.I. method of analysis whilst C.P. 110 overestimated these moments by between 25 and 50 per cent.

The results of eight tests on post-tensioned unbonded flat slabs involving both shear and moment transfer at columns are presented. The amount of moment transferred to the columns is compared with predictions based on frame analysis and finite element analysis. A comparison is also made of the shear capacity with that predicted by the British and American codes and an improved method is proposed. The proposed method was found to give more consistent results than those found using either of the current recommendations.