The Interplanetary Network Supplement to the BeppoSAX Gamma-Ray Burst Catalogs

Between 1996 July and 2002 April, one or more spacecraft of the interplanetary network detected 787 cosmic gamma-ray bursts that were also detected by the Gamma-Ray Burst Monitor and/or Wide-Field X-Ray Camera experiments aboard the BeppoSAX spacecraft. During this period, the network consisted of up to six spacecraft, and using triangulation, the localizations of 475 bursts were obtained. We present the localization data for these events.Comment: 89 pages, 3 figures. Submitted to the Astrophysical Journal Supplement Serie

Knitted electromagnetic textile surfaces

We report a commercially attractive approach to manufacturing conducting textiles which is based on computerised flat-bed knitting technology using conducting yarns. We examine how flat-bed knitting can be used to manufacture large area samples of functional electromagnetic structures such as frequency selective surfaces (FSS). In addition we show how the knitting process can be adapted to allow the integration of conducting vias into a 3-D knitted spacer structure to form an electromagnetic high impedance surface (HIS)

Ignition characteristics of the nickel-based alloy UNS N07718 in pressurized oxygen

The development of ignition and combustion in pressurized oxygen atmospheres was studied for the nickel based alloy UNS N07718. Ignition of the alloy was achieved by heating the top. It was found that the alloy would autoheat to destruction from temperatures below the solidus temperature. In addition, endothermic events occurred as the alloy was heated, many at reproducible temperatures. Many endothermic events occurred prior to abrupt increases in surface temperature and appeared to accelerate the rate of increase in specimen temperature. It appeared that the source of some endotherms may increase the oxidation rate of the alloy. Ignition parameters are defined and the temperatures at which these parameters occur are given for the oxygen pressure range of 1.72 to 13.8 MPa (250 to 2000 psia)

Ignition characteristics of the iron-based alloy UNS S66286 in pressurized oxygen

The development of ignition and combustion in pressurized oxygen atmospheres was studied for the iron based alloy UNS S66286. Ignition of the alloy was achieved by heating the top surface of a cylindrical specimen with a continuous-wave CO2 laser. Two heating procedures were used. In the first, laser power was adjusted to maintain an approximately linear increase in surface temperature. In the second, laser power was periodically increased until autoheating (self-heating) was established. It was found that the alloy would autoheat to destruction from temperatures below the solidus temperature. In addition endothermic events occurred as the alloy was heated, many at reproducible temperatures. Many endothermic events occurred prior to abrupt increases in surface temperature and appeared to accelerate the rate of increase in specimen temperature to rates greater than what would be expected from increased temperature alone. It is suggested that the source of these endotherms may increase the oxidation rate of the alloy. Ignition parameters are defined and the temperatures at which these parameters occur are given for the oxygen pressure range of 1.72 to 13.8 MPa (25 to 2000 psia)

Technology Use Rationale and Assimilation in the Implementation of Electronic Data Interchange

This study explores how rationales for information technology use relate to the extent of its assimilation in organizations and considers whether and how rationales associated with the technology-in-practice are transformed as the organization makes use of the technology. A multiple-case study of electronic data interchange (EDI) adoption and assimilation was analyzed, looking at both institutional and strategic rationales for EDI use. The degree of assimilation was greatest among those organizations that cited a strategically-oriented rationale for using EDI. The study also found evidence of a shift from institutional to strategic rationales in several organizations as they decided to extend their use of EDI beyond their initial implementation. Shifts in rationale emerged as organizational members gained greater exposure to the organizing vision of the larger EDI community and, to a lesser extent, as they experienced improvements in organizational performance through the use of EDI

Experimental knitted, textile frequency selective surfaces

A new approach to the manufacture of conducting textiles for operation at microwave frequencies is reported. The technique investigated utilises a commercial flat-bed knitting process which is configured to use conducting yarns to produce large area, patterned, conducting textiles in an efficient manner which is amenable to mass production. The computerised flat-bed knitting system is used to manufacture example frequency selective surfaces (FSSs) using silver coated nylon yarn combined with a polyester base yarn. Reflectivity measurements are presented to confirm the basic operation of both a lowpass and a highpass knitted, textile FSS

Detailed transonic flow field measurements about a supercritical airfoil section

The transonic flow field about a Whitcomb-type supercritical airfoil profile was measured in detail. In addition to the usual surface pressure distributions and wake surveys, schlieren photographs were taken and velocity vector profiles were determined in the upper surface boundary layer and in the near wake. Spanwise variations in the measured pressures were also determined. The data are analyzed with the aid of an inviscid transonic finite-difference computer program as well as with boundary layer modeling and calculation schemes

Spectral Analysis of GRBs Measured by RHESSI

The Ge spectrometer of the RHESSI satellite is sensitive to Gamma Ray Bursts (GRBs) from about 40 keV up to 17 MeV, thus ideally complementing the Swift/BAT instrument whose sensitivity decreases above 150 keV. We present preliminary results of spectral fits of RHESSI GRB data. After describing our method, the RHESSI results are discussed and compared with Swift and Konus.Comment: 4 pages, 4 figures, conference proceedings, 'Swift and GRBs: Unveiling the Relativistic Universe', San Servolo, Venice, 5-9 June 2006, to appear in Il Nouvo Ciment

Experimental knitted, textile frequency selective surfaces

A new approach to the manufacture of conducting textiles for operation at microwave frequencies is reported. The technique investigated utilises a commercial flat-bed knitting process which is configured to use conducting yarns to produce large area, patterned, conducting textiles in an efficient manner which is amenable to mass production. The computerised flat-bed knitting system is used to manufacture example frequency selective surfaces (FSSs) using silver coated nylon yarn combined with a polyester base yarn. Reflectivity measurements are presented to confirm the basic operation of both a lowpass and a highpass knitted, textile FSS

Knitted waveguide antenna

This paper presents the design of a knitted slotted waveguide antenna and its improvement. The antenna is developed originally from a textile elliptical waveguide and it has a resonant frequency at 9.15GHz with 80MHz bandwidth. Then, slight structural adjustments are taken to improve the antenna’s performance. Moreover, the measured results show that the optimized slotted waveguide antenna working at 9.18GHz with 170 MHz bandwidth has a more directional radiation pattern with a higher gain. The antenna was designed and simulated in CST Microwave Studio 2012