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This paper investigates the required size of a plate heat exchanger to be used in a bottoming organicRankine cycle to recover waste exhaust heat from a piston aero-engine. The objective of the sizing is tominimise the heat exchanger weight, while ensuring a minimal pressure drop in the working fluid and exhaustgas flows. Two engines are considered that are typical of small (Continental IOF-240, 125BHP) and large(Lycoming IO-720, 400BHP) piston-engine aircraft. The sizing analysis was conducted using MCycle, anopen-source Python package for 1D sizing of power cycle components. It has been identified that the heatexchanger port diameters and exhaust gas channel spacing can contribute significant pressure losses if notappropriately sized. An optimised weight of 7.80 kg for the IOF-240 and 29.8 kg for the IO-720 is possibleusing titanium plates.

A major problem in the geotechnical approach to the stability of natural slopes is that there is usually little information on the in-situ geotechnical conditions, because of the extreme difficulty associated with ground investigations of steep slopes covered with vegetation. In this study, a lightweight dynamic cone penetration test (LWDCPT) has been introduced for a geotechnical survey of natural weathered granitic (Masado) slopes. Based on a series of direct shear tests, the internal friction angle and the apparent cohesion of reconstituted Masado soil were found to be fairly closely related to the void ratio and the degree of saturation in the soil. From the laboratory calibration tests, an equation was created to relate the dynamic cone resistance (qd) and the void ratio of reconstituted Masado under different degrees of saturation. Equations were developed to calculate the internal friction angle and the apparent cohesion from the value of qd for Masado at a known degree of saturation. LWDCPT and direct shear tests were carried out on undisturbed samples taken from a natural Masado slope. The estimated internal friction angle and the apparent cohesion calculated with the value of qd in the LWDCPTs agreed fairly well with those of tests on the undisturbed samples obtained in laboratory shear tests.

YohRoh observed a large solar flare (X9/2B) on November 6, 1997. The flare showed strong gamma-ray emission between 11 :S2 and 11:56 UT (peak phase) and several gamma-ray lines were detected. After 11: 56 UT a weak and extended gamma-ray emission was measured. The ratio of Mg+Si+Fe to C+O+Ne line fluxes was enhanced by a factor of about three in the extended phase. The Oriented Scintillation Spectrometer Experiment (OSSE) on board the Compton Gamma-Ray Observatory (CGRO) detected significant neutrons associated with the flare between 12:08 and 12:30 UT. The observed neutron count-rate time profile suggests that neutrons originated in interactions that occurred in both peak and extended phases., Published in Advanced Space Research, v30 n3 p629-634, 2002.

The HXS and GRS detectors on Yohkoh observed the 2000 July 14, X5.7 flare, beginning at 10:20 UT, 4 m before the peak in soft X rays. The hard X rays and rays peaked 3 m later at 10:27 UT. Solar -ray emission lasted until 10:40 UT. Impact of high-energy ions at the Sun is revealed by the -ray lines from neutron capture, annihilation radiation and de-excitation that are visible above the bremsstrahlung continuum. From measurement of these lines we find that the flareaveraged spectrum of accelerated protons is consistent with a power law 10 MeV with index 3.14 0.15 and flux 1.1 10(expn 32) MeV 1 at 10 MeV. We estimate that there were 1.5 10(expn 30) erg in accelerated ions if the power law extended without a break down to 1 MeV; this is about 1% of the energy in electrons 20 keV from measurements of the hard X rays. We find no evidence for spectral hardening in the hard X rays that has been suggested as a predictor for the occurrence of solar energetic particle (SEP) events. This was the third largest proton event above 10 MeV since 1976. The GRS and HXS also observed -ray lines and continuum produced by the impact of SEP on the Earth s atmosphere beginning about 13 UT on July 14. These measurements show that the SEP spectrum softened considerably over the next 24 hours. We compare these measurements with proton measurements in space., 2001, Solar Physics, 204: p. 43. Prepared in collaboration with the Hughes/STX Corp, NASA Goddard Space Flight Center, Greenbelt, MD, and the Department of Physics, Rikkyo University, Tokyo, Japan.