In this work, an estimation of the key rate of measurement-device-independent quantum key distribution (MDI-QKD) protocol in free space was performed. The examined free space links included satellite-earth downlink, uplink and intersatellite link. Various attenuation effects were considered such as diffraction, atmosphere, turbulence and the efficiency of the detection system. Two cases were tested: asymptotic case with infinite number of decoy states and one-decoy state case. The estimated key rate showed the possibility of applying MDI-QKD in earth-satellite and intersatellite links, offering longer single link distance to be covered.
Most available methods for unit hydrographs (SUH) derivation involve manual, subjective fitting of
a hydrograph through a few data points. The use of probability distributions for the derivation of synthetic
hydrographs had received much attention because of its similarity with unit hydrograph properties. In this
paper, the use of two flexible probability distributions is presented. For each distribution the unknown
parameters were derived in terms of the time to peak(tp), and the peak discharge(Qp). A simple Matlab
program is prepared for calculating these parameters and their validity was checked using comparison
with field data. Application to field data shows that the gamma and lognormal distributions had fit well.<
This research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers a
... Show MoreThis study addresses quantum computers as one of the most significant contemporary technological transformations that promise to reshape the future of global computing. It aims to clarify the conceptual foundations of quantum computing and to identify the fundamental differences between quantum and classical computers in terms of processing mechanisms, computational speed, and the ability to solve highly complex problems. The study focuses on key concepts such as the qubit, superposition, and entanglement, highlighting their role in enabling computational capabilities that exceed the limits of classical computing. It also discusses the future applications of quantum computers in areas such as cryptography, artificial intelligence, big data
... Show MoreCeliac disease (CD) is the most common genetically - based disease in correlation with food intolerance. The aim of this study is to measure the activity of ALT enzyme and purify enzyme from sera women with celiac disease. Alanine aminotransferase (ALT) activity has been assayed in (30) women serum samples with celiac disease, age range between (20-40) year and (30) serum of healthy women as control group, age range between (22-38) year. In the present study, the mean value of ALT activity was significantly higher in patients with celiac disease than healthy group (p<0.01). The ALT enzyme was partial purified from sera women with celiac disease by dialysis, gel filtration using Sephadex G- 50 and ion exchange chr
... Show MoreCeliac disease (CD) is the most common genetically - based disease in correlation with food intolerance. The aim of this study is to measure the activity of ALT enzyme and purify enzyme from sera women with celiac disease. Alanine aminotransferase (ALT) activity has been assayed in (30) women serum samples with celiac disease, age range between (20-40) year and (30) serum of healthy women as control group, age range between (22-38) year. In the present study, the mean value of ALT activity was significantly higher in patients with celiac disease than healthy group (p<0.01). The ALT enzyme was partial purified from sera women with celiac disease by dialysis, gel filtration using Sephadex G- 50 and ion exchange chromatography using DEAE- cell
... Show MoreTo improve the efficiency of a processor in recent multiprocessor systems to deal with data, cache memories are used to access data instead of main memory which reduces the latency of delay time. In such systems, when installing different caches in different processors in shared memory architecture, the difficulties appear when there is a need to maintain consistency between the cache memories of different processors. So, cache coherency protocol is very important in such kinds of system. MSI, MESI, MOSI, MOESI, etc. are the famous protocols to solve cache coherency problem. We have proposed in this research integrating two states of MESI's cache coherence protocol which are Exclusive and Modified, which responds to a request from reading
... Show MoreBecause of Cadmium selenide quantum dots (CdSe quantum dots) has a tuning energy gap in the visible light range, therefore; it is provided a simple theoretical model for the absorption coefficient of CdSe quantum dots, where the absorption coefficient determines the extent to which the light of a material can penetrate a specific wavelength before it is absorbed. CdSe quantum dots have an energy gap can be controlled through two effects: the temperature and the dot size of them. It is found that; there is an absorption threshold for each directed wavelength, where CdSe quantum dots begin to absorb the visible spectrum at a size of 1.4 nm at room temperature for a directed wavelength 3
Gas sensors are essential for detecting noxious gases that have a detrimental effect on people's health and welfare. Carbon quantum dots (CQDs) are the fundamental component of gas detectors. CQDs and graphene (Gr) were prepared using the electrochemical method. The gas sensitivity of these materials was evaluated at different temperatures (150, 200, 250 °C) to assess their effectiveness. Subsequently, experiments were conducted at different temperatures to ascertain that the combination of CQDs and Gr, with various percentages of Gr and CQDs, exhibited superior gas sensitization properties compared to CQDs alone. This was evaluated based on criteria such as sensitivity, recovery time, and reaction time. Interestingly, the combination was
... Show MoreIn the present work, a D.C. magnetron sputtering system was
designed and fabricated. This chamber of this system includes two
coaxial cylinders made from copper .the inner one used as a cathode
while the outer one used as a node. The magnetic coils located on
the outer cylinder (anode) .The profile of magnetic field for various
coil current (from 2Amp to 14Amp) are shown. The effect of
different magnetic field on the Cu thin films thickness at constant
pressure of 7x10-5mbar is investigated. The result shown that, the
electrical behavior of the discharge strongly depends on the values
of the magnetic field and shows an optimum value at which the
power absorbed by the plasma is maximum. Furthermore, the
pl