30,199 research outputs found
Low temperature thermochronology using thermoluminescence signals from quartz
Isothermal thermoluminescence (ITL) and thermoluminescence (TL) signals from quartz were studied. A single aliquot regenerative dose protocol has been applied for ITL De determination (SAR-ITL). In the SAR-ITL protocol, the preheat condition was a cutheat to 10 °C higher than measurement temperature. The test dose was approximate to the expected De, and a 450 °C heat was given at end of each cycle to minimize signal build-up. Based on signals strength and dose recovery test, temperatures of 235 and 255 °C were selected for the ITL De measurement. A multiple aliquots regenerative protocol has been applied for TL De determination (MAR-TL). The preheat procedure was a cutheat of 235 °C and a second glow TL of 175 Gy was used for normalization. The sensitivity change of first heating to 450 °C was negligible, supported by comparison between additive and regenerative dose growth curves. Based on the natural TL signal and preheat condition studies, De values at temperatures of 250–330 °C were used for thermochronological study. These two protocols were applied to rock samples collected at different elevations from Nujiang River (also called Salween River) valley slope. The SAR-ITL gave De results consistent with the MAR-TL at temperatures of 40–50 °C higher. The results clearly demonstrate the differences in the thermal histories between the analyzed samples. The SAR-ITL and MAR-TL protocols were both found to be suitable for application in thermochronology.postprin
Inclusion of interbar currents in a network-field coupled time-stepping finite-element model of skewed-rotor induction motors
Author name used in this publication: S. L. HoAuthor name used in this publication: W. N. FuVersion of RecordPublishe
A novel approach to circuit-field-torque coupled time stepping finite element modeling of electric machines
Author name used in this publication: S. L. HoAuthor name used in this publication: W. N. FuAuthor name used in this publication: H. C. WongH.C. Wong, Industrial Centre2000-2001 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Return to work after stroke in Hong Kong. Part 2: a psychosocial perspective
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An effective method to reduce the computing time of nonlinear time-stepping finite-element magnetic field computation
Author name used in this publication: W. N. FuAuthor name used in this publication: S. L. HoAuthor name used in this publication: H. C. Wong2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Petrochemistry and mineral chemistry studies on metamorphic ultramafic rocks in Yanghou area, Zhenghe Country, Fujian Province, China
Petrochemistry studies indicate that the Yanghou metamorphic ultramafic rocksare composed of metamorphosed harzburgite and burgite and ultramafic cumulate . Trace element geochemistry and mineral chemistry studies on the metamorphosed harzburgite indicate that it is the relict of the depleted mantle. From systematic studies on petrochemistry , mineral chemistry and geochronology, it s concluded that the Yanghou metamorphic ultramafic rocks are components of Later Sinian-Early Paleozoic ophiolite in South China.岩石化学研究表明, 洋后变质超镁铁岩是由变质方辉橄榄岩和变质超镁铁堆积岩组成。变质方辉橄榄岩的微量元素地球化学及矿物化学特征表明, 应为亏损的残余地慢产物。通过系统的岩石地球化学、矿物化学及年代学研究, 认为洋后变质超镁铁岩可能为华南晚震旦一早古生代的蛇绿岩组成部分。published_or_final_versio
A multislice coupled finite-element method with uneven slice length division for the simulation study of electric machines
Author name used in this publication: W. N. FuAuthor name used in this publication: S. L. HoAuthor name used in this publication: H. C. Wong2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Return to work after stroke in Hong Kong. Part 1: a biological perspective
published_or_final_versio
A Period-Reconfigurable Leaky-Wave Antenna with Fixed-Frequency and Wide-Angle Beam Scanning
© 1963-2012 IEEE. A novel fixed-frequency beam-scanning leaky-wave antenna (LWA) based on a period-reconfigurable structure is presented. Operating at 5 GHz, the antenna consists of a slotted substrate integrated waveguide and 54 electrically small patches. Each patch element is etched with two dumbbell-shaped slots, and its operating state can be flexibly controlled by the biasing of the p-i-n diode on a parasitic strip. An ideal array model employing isotropic point sources is used for the analysis on the scanning mechanism, based on which a new method for suppressing the higher order space harmonics is developed. Using this method, the monoharmonic radiation range can be dramatically extended, and a wide-angle beam scanning can be achieved by manipulating the period length of the LWA. An FPGA controlling platform is designed for the electronic control of the antenna. The measured results validate that the proposed antenna achieves good performance of wide-angle scanning (125°) with a peak gain of 11.8 dBi at a fixed frequency
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