Quantum key distribution (QKD) provides unconditional security in theory. However, practical QKD systems face challenges in maximizing the secure key rate and extending transmission distances. In this paper, we introduce a comparative study of the BB84 protocol using coincidence detection with two different quantum channels: a free space and underwater quantum channels. A simulated seawater was used as an example for underwater quantum channel. Different single photon detection modules were used on Bob’s side to capture the coincidence counts. Results showed that increasing the mean photon number generally leads to a higher rate of coincidence detection and therefore higher possibility of increasing the secure key rate. The secure key rate can reach 0.0239 (bits/pulse) with a quantum bit error rate (QBER) of 3.2% for the free space channel and 1.5% for the simulated sea-water channel. The security parameters for each value of the mean photon number closely align with the corresponding theoretical predictions. However, some discrepancies were observed, primarily due to a mismatch in photon detection efficiency for SPDMs and system fluctuations. The theoretical calculations also predict that using coincidence detection, the key can be distributed over distances of up to 195 km.
The possibility of implementing smart mobility in the traditional city: Studying the possibility of establishing an intelligent transportation system in the city center of Kadhimiya
This research aims to choose the appropriate probability distribution to the reliability analysis for an item through collected data for operating and stoppage time of the case study.
Appropriate choice for .probability distribution is when the data look to be on or close the form fitting line for probability plot and test the data for goodness of fit .
Minitab’s 17 software was used for this purpose after arranging collected data and setting it in the the program.
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... Show MoreIn this work, the effects of solvent properties on the characteristics of absorption and fluorescence for two laser dyes was studied. Dyes used in this work include Coumarin 5400 and DCM, while the solvents include ethanol, methanol, acetone, propanol and chloroform. Coumarin 5400 dye shows sharp fluorescence peaks in the green band of visible region while the DCM dye shows relatively wide band within 590-630 nm. Therefore, the selection of any dye for random gain medium applications should be performed after determining the most appropriate solvent as the optimum fluorescence characteristics are obtained.
A field experiment was conducted at Abu-Ghrib during 2013- 2014 season to study the effect of harrowing systems on the decomposition and fermentation on organic matter(OM) when added and mixed with the soil under special technology, as well as its effect on the growth parameters and productivity of (Zea mays L. 5018). The experiment was laid out using factorial randomized complete block design (RCBD) in split-split design with three replications in SCL bare soil with a percent of moisture ranged from 16 – 18 %. The main plots were designated to the two systems of harrowing (Rotary Harrowand Disc Harrow ). The sub main plots were specified for two organic matters ( Sheep manure ,cow manure ) . Data were statistically analyzed, and
... Show MoreThis study was carried out to determine the effects of NaCl (0.00, 50, 100, 150, 180 or 200) mM and two different types of mutagens chemical mutagen ethyl methyl sulphonate (EMS) at 0.5% and physical mutagen UV-B irradiation (40 min time exposure), on mitotic division in two Iraqi rice genotypes Amber 33 (A33) and Amber Baghdad (AB). Different concentrations of NaCl were used. Mitotic index (MI %) was decreased significantly by increasing NaCl concentration, however the highest mitotic index was recorded in mutated genotypes with EMS and UV-B. Different abnormal chromosomes were noticed in mutated plants. Results showed high percentage of abnormal chromosomes in EMS mutated genotypes. In addition no significant differences between genotypes
... Show MoreThis paper studied the behaviour of reinforced reactive powder concrete (RPC) two-way slabs under static load. The experimental program included testing three simply supported slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. Tested specimens were of identical properties except their steel fibers volume ratio (0.5 %, 1 %, and 1.5 %). Static test results revealed that, increasing steel fibers volume ratio from 0.5% to 1% and from 1% to 1.5%, led to an increase in: first crack load by (32.2 % and 52.3 %), ultimate load by (36.1 % and 17.0 %), ultimate deflection by (33.6 % and 3.4 %), absorbed energy by (128 % and 20.2 %), and the ultimate strain by (1.1 % and 6.73 %). The stiffness and ductility of the specimens also increased. A
... Show MoreThree-dimensional nonlinear thermal numerical simulations are conducted for the friction stir welding (FSW) of AA 7020-T53. Three welding cases with tool (rotational and travel) speeds of 900rpm-40mm/min, 1400rpm-16mm/min and 1400rpm-40mm/in are analyzed. The objective is to study the variation of transient temperature in a friction stir welded plate of 5mm workpiece thickness. Based on the experimental records of transient temperature at several specific locations during the friction stir welding process for the AA 7020-T53, thermal numerical simulation is developed. The numerical results show that the temperature field in the FSW process is symmetrically distributed with respect to the welding line, increasing travel speed decreasing tran
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