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 The real-time sensing performance of the new intelligent cooperative spectrum sensing based on the denoised mixed feature method paired with K-M edoids is verified.  Two RTL-SDR hardware receivers, a host laptop computer, and a USRP-SDR hardware transmitter are used.  The theoretical and practical sensing performance validity of the developed scheme is confirmed based on the SDR platform.In this paper, the software and hardware of a software-defined radio (SDR) platform are used to implement and verify the blind real-time sensing act of intelligent collaborative spectrum sensing based on a new theoretical formula for constructing denoised mixed features named M SKU3 and paired with an unsupervised machine learning K-M edoids algorithm. Two low-cost RTL-SDR dongle hardware receivers are used as two cooperative unlicensed secondary users to capture the radio frequency of a licensed primary user channel. A host personal computer is used as a fusion center to run GNU-Radio software signal processing blocks to implement the developed method, and a single Universal Software Radio Peripheral (USRP) N210 hardware transmitter based on FPGA is used to take up unoccupied desired radio frequency bandwidth. Two scenarios of signal-to-noise ratio levels have been adopted to verify and test the sensing performance of the developed system. The first one occurs when unlicensed secondary users have equal signal-to-noise ratio values. The second occurs when unlicensed secondary users have different signal-to-noise ratio values since each secondary user has their location. The experimental results of detecting action in terms of the probability of detection for the proposed method show that the theoretical and practical results are very close to each other.

Henna leaves are a pri or ity ma te rial for hair dyes and body tat toos and have been used for this pur pose for de cades. In Iraq, henna is used widely but it re quires sub stan tial con trols. Iraq is con sid ered an en vi ron men tally pol luted area as a re sult of the wars it has ex pe ri enced, hence, this study has been con ducted to cal cu late the level of 222 Rn con tam i na tion in henna leaves using a CR-39 nu clear track de tec tor. The leaves were col lected from the prov ince of Basrah, which is lo cated in south ern Iraq and is fa mous for cul ti va tion of this plant. The ra don concen tra tions were found to range from 12.140 to 16.255 Bqm-3 in Al-Faw, and from 7.613 to 11.111 Bqm-3 in Abu Al Khasib. Ra don ac tiv ity ranged from 6.09×10-4 to 8.16×10-4 Bq in Al-Faw, whereas, in Abu Al Khasib it ranged from 3.82×10-4 to 5.58×10-4 Bq. Ra don specific ac tiv ity ranged from 1.22×10-4 to 1.63×10-4 Bqg-1 in Al-Faw, and from 7.64×10-5 to 1.12×10-4 Bqg-1 in Abu Al Khasib. The ra don ex ha la tion rate ranged from 4.05×10-4 to 5.43×10-4 with an av er age of 4.69×10-4 Bqm-2 d-1 in Al-Faw, and from 2.54×10-4 to 3.71×10-4 with an av er age of 3.22×10-4 Bqm-2 d-1 in Abu Al Khasib. Af ter ob tain ing the re sults, one can con clude that the henna plant col lected from these ar eas is safe for hu man use and is free from high rates of 222 Rn.