Inhabitants of the Mongolian Plateau have been staunchly nomadic. Cities rarely existed before the Russian hegemony, and at that point they first attached themselves to pre-existing Buddhist ...monasteries. The exception to this general pattern was the Uighurs, who had an empire in the eighth and early ninth centuries. They built several cities, extended and maintained a flourishing trade network, established sufficient agriculture and developed urban manufacturing. Although historians have pointed out these significant distinctions, few have fully considered the thoroughly revolutionary impact of this Turkish group on steppe culture. One result in the Orkhon Valley was the foundation for Karakorum, the only permanent seat of the imperial Mongols in the thirteenth century. That city occupied the same site and, in the early seventeenth century, served as building material for the major religious centre of Erdene Zuu accompanying the re-introduction of Buddhism. Therefore, the Uighurs affected the physical heartland of their empire for a millennium and the habits of the people to this day.
Valuing a practice for purchase or sale Kolbas, J W
Indiana medicine : the journal of the Indiana State Medical Association,
1992 May-Jun, Letnik:
85, Številka:
3
Magazine Article
Staff development: making one plus one equal three Kolbas, J W; McWilliams, K A
Indiana medicine : the journal of the Indiana State Medical Association,
1992 Mar-Apr, Letnik:
85, Številka:
2
Magazine Article
Multiplexing of radiation detectors reduces the number of readout channels, which in turn reduces the number of digitizer input channels for data acquisition. We recently demonstrated frequency ...domain multiplexing (FDM) of pulse mode radiation detectors using a resonator that converts the detector signal into a damped sinusoid by convolution. The detectors were given unique ”tags” by the oscillation frequency of each resonator. The charge collected and the time-of-arrival of the detector pulse were estimated from the corresponding resonator output in the frequency domain.
In this paper, we demonstrate a new method to recover the detector pulse from the damped sinusoidal output by deconvolution. Deconvolution converts the frequency-encoded detector signal back to the original detector pulse. We have developed a new prototype FDM system to multiplex organic scintillators based on convolution and deconvolution. Using the new prototype, the charge collected under the anode pulse can be estimated from the recovered pulse with an uncertainty of about 4.4 keVee (keV electron equivalent). The time-of-arrival can be estimated from the recovered pulse with an uncertainty of about 102 ps. We also used a CeBr3 inorganic scintillator to measure the Cs-137 gamma spectrum using the recovered pulses and found a standard deviation of 13.8 keV at 662 keV compared to a standard deviation of 13.5 keV when the original pulses were used. Coincidence measurements with Na-22 using the deconvolved pulses resulted in a timing uncertainty of 617 ps compared to an uncertainty of 603 ps using the original pulses. Pulse shape discrimination was also performed using Cf-252 source and EJ-309 organic scintillator pulses recovered by deconvolution. A figure of merit value of 1.08 was observed when the recovered pulses were used compared to 1.2 for the original pulses.
Frequency domain multiplexing of pulse mode radiation detectors Mishra, M.; Mattingly, J.; Mueller, J.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2018, Letnik:
902, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The capability to multiplex scintillation detectors or other pulse mode radiation detectors is necessary in some applications where a large number of detectors is required. Frequency domain ...multiplexing has been previously implemented for applications in astronomy using amplitude modulation on radiation detectors such as transition-edge sensors. We propose an alternative method for multiplexing pulse mode radiation detectors in the frequency domain using convolution. We pass the detector signal to a resonator circuit that converts a detector pulse to a damped sinusoid of a specific frequency which gives a unique tag to the detector. We have developed a prototype frequency-domain multiplexed system for four EJ-309 organic scintillator detectors using four resonators of unique frequencies. The resonator outputs are combined using a fan-in circuit which is then connected to a single digitizer input. Using this system, we demonstrate that the charge collected under the original anode pulse can be estimated from the power spectrum of the damped sinusoid with a relative uncertainty of about 2%. The time-of-arrival of the anode pulse can be estimated using constant fraction discrimination applied to the leading edge of the damped sinusoid with an uncertainty of about 450 ps. We also used a CeBr3 detector to test the performance of our system for spectroscopic applications and found only small degradation in the resolution for a multiplexed detector.
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