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Two classical scenarios in space communications can be examined to evaluate the link performance of free space optical communications (FSO). These scenarios include the downlink and uplink between earth ground stations and near earth geostationary (GEO) satellites, as well as between the earth and spacecraft that are located a significant distance from the earth (i.e., one or more astronomical units (AU) away). Deep space is often defined as being more than 0.01 AU, or around 1,500,000 km, from Earth. In the first part of this analytical research, various practical system characteristics for optical lasers, telescopes, transmitters, receivers, and atmospheric disturbances, including absorption and scintillation, are taken into consideration. The simulation outcomes were compared to significant experimental data from DLR & JAXA's OICETS/Kirari-Japan to validate the extended simulation model. Additionally, this work will propose a synthetic effects-based optical turbulence generator in order to deeply investigate atmospheric turbulence disturbances in free-space optical communication systems and support the advancement of artificial intelligence processing-based mitigation solutions. Worth mentioning, the initial outcomes and analytical comparisons demonstrate the preliminary viability of the simulation model for the link budget and scintillation estimation for FSO investigations, which can give deep insight into the development of the proposed testbed prototyping, machine learning-based laboratory measurement system, and enhancement possibility for FSO project design and execution for longand medium-term space mission planning. [ABSTRACT FROM AUTHOR]

Fault detection is a critical stage in power systems, requiring swift and accurate identification. This paper introduces an Artificial Neural Network (ANN) tailored for fault identification, utilizing a deep learning approach. The proposed model marks a pioneering effort, employing ANN for fault identification using raw and sampled data from three-phase current and voltage signals collected through simulation from a 14-bus system across various fault and no-fault classes. Performance evaluation metrics such as accuracy, sensitivity, specificity, precision, and F1 score are employed to assess the model's efficacy. Results demonstrate that the ANN model achieves exceptional accuracy and efficiency in fault detection, showcasing its potential as a pivotal tool for enhancing the reliability and performance of electrical power systems. Notably, the suggested model attains a remarkable 99% accuracy across all tested fault scenarios, F1Score 0.99 for fault and non-fault detection with closely matched testing and training loss curves. [ABSTRACT FROM AUTHOR]

Patients admitted with heart failure facing a high risk of mortality where 30-day mortality rates are reaching 10%. Identifying patients with high and low risk of mortality could improve clinical outcomes and hospital resource allocation. Existing mortality predictors use statistical and mathematical models that are difficult to obtain where it requires the researcher to understand the relationship between variables that exist in the models. Furthermore, the statistical model consumes a lot of time to build it and it requires experts and requires a lot of effort to build such models. As an alternative approach, machine learning techniques have become very popular to solve problems for forecasting and predictions. This paper proposed the use of machine learning to predict mortality for heart failure patients. Results shows that machine learning techniques able to produce good prediction accuracy. Support Vector Machine produces the best prediction accuracy which test dataset accuracy is at 85% and overall prediction accuracy is at 86.67% [ABSTRACT FROM AUTHOR]

The purpose of the current work is to investigate the influence of a partial replacement of Cadmium (Cd) for yttrium (Y) on the electrical characteristics of yttrium-based alloys of the Y1-xcdxBa2Cu2.8Zn0.2O6+δ Superconducting compound, where x=0, 0.05, 0.1, 0.15,0.2 and 0.25. Using the solid-state reaction approach, the samples were produced (SSR). The samples were sintered in normal air at temperatures of 850 degrees Celsius for 24 hours at a rate of 10 degrees Celsius per minute. The Four-Probe Technique was used to obtain All samples exhibited superconducting behavior at temperatures below their critical temperatures. The samples showed superconducting behaviour, with the highest critical temperature (Tc (offset)) equal to 108.5 K and the highest energy gap value (Eg)=0.033034eV at the Cadmium concentration x=0.05. [ABSTRACT FROM AUTHOR]

This research prepared the compound Hg-base superconductors Hg1-xAgxBa2 Ca2Cu2.8Cd0.2 O8+δ with substitution of (x=AgO) with concentration x=(0.0, 0.05, 0.1, 0.15, 0.2,and 0.25) by Hg through method of powder metallurgy (solid-state reaction) together temperature of sintering 750OC for 24h. The Studied improvement of structural and electrical properties for composition substations. After the x-ray scattering tests were completed, the results were analyzed to determine all cell units' configuration and lattice constants (a,b,c). The diffraction of the x-ray revealed that all samples have crystals and a tetragonal structure. The analysis of the electrical characteristics to obtain critical temperature was carried out using four-probe point devices, with the highest heating value being found when x=0.15 equals 122.9K for Hg0.85AgO0.15Ba2Ca2Cu3O8+δ compound, all other samples have the highest 1223 main phases compared to the other phases. [ABSTRACT FROM AUTHOR]

This research studied the effect of high temperature and silica fume as a replacement material in concrete. Compressive strength, tensile strength and flexural strength were studied. All specimens were studied at 23c° and three high temperatures (150c°,350c° and 550c°). Results showed that drop in hardened properties decreased with increasing temperature as silica fume replacing ratio increase. Optimum replacing ratio was about 30% resulted in the best hardened properties of concrete. As age progress for concrete from 7 days to 90 days drop in hardening properties reduced gradually. Finally, results showed that pH slight deceasing in age (1, 7, 28 and 90) days for all temperatures. [ABSTRACT FROM AUTHOR]

In this study, modelling and simulation of batch adsorption of organic dye of methylene blue (MB) by using modified metal-organic framework-5 (MOF-5) were investigated. The film-pore diffusion model was developed based on external mass transfer coefficient (kf) and pore diffusion coefficient (Dp) that governs the mass transfer process in batch organic dye adsorption. These two parameters were estimated using a program written in Matlab software by corresponding the simulation data with the experimental data obtained from previous study. Based on the findings, the estimated mass transfer coefficient and pore diffusion coefficient were 66.8 m/s and 2.15×10-7 m2/s, respectively. Applying the estimated parameters, the MB adsorptions by using modified MOF-5 were investigated to observe the effects of MOF-5 modification, initial dye concentration, temperature, and the dosage of adsorbent. It was found that the adsorption capacity of modified MOF-5 (H6P2W18O62/MOF-5) was higher than pure MOF-5. Besides, the lower initial MB dye concentration, higher temperature, and lower adsorbent dosage result in higher dye adsorption capacity. [ABSTRACT FROM AUTHOR]

A theoretical studies and calculation the cross-section for electron transfer at metal/semiconductor interfaces material depending on quantum description. Cross sections of charge transfer for Ag with Si ,TiO2 ,and ZnO were carried out using simplified models of the system at the Multi driving force energy at interaction in the devices interface. Investigation and evaluation of the cross section for electron transfer aET at metal/semiconductor system is depending on the coefficient; driving force energy (ϑ), transfer energy orientation energy, wave number ϑ, mean Refractive index n, amplitude of electronic coupling coefficient 〈 | Λ (0) ¯ | 2 〉 and the lifetime of electron transfer τET. The cross section for electron transfer σET at metal/semiconductor system evaluated using MATLAP program. The result of cross section show that cross section increases with increasing the driving force energy and coupling coefficient and vice versa. [ABSTRACT FROM AUTHOR]

The present work includes studying the effect of the partial substitution of the lanthanum (La) instead of the yttrium (Y) on the electrical properties of the Y1-xLaxBa2Cu3O6+δ Superconducting compound, where x=0, 0.05, 0.1, 0.15 and 0.2. Samples were prepared by solid state reaction method (SSR). The samples were sintered in normal air and under temperatures 800 oC For 48 hours with the heating rate 10oC/min. The Four-Probe Technique was used to obtain values of the critical temperatures, The samples showed all have superconducting behavior and the highest critical temperature Tc(offset) = 104.8 K and the highest energy gap value (Eg)=0.031907 at lanthanum concentration x= 0.15. The X-ray diffraction of the compound Y1-xLaxBa2Cu3O6+δ, which represents the high phase of the superconducting system (YBCO) changing with increase La concentration. It was observed the formation of high phases in all the prepared samples with the presence of some impurities. [ABSTRACT FROM AUTHOR]

The present work includes studying the effect of partial substitution of lead (Pb) by Antimony (Sb) on the structure properties of Pb1-xSbxBa2Ca2Cu3O10 compound, where (x= 0, 0.05, 0.1, 0.15, 0.20 and 0.25). Samples were prepared by solid state reaction (SSR) methods. Samples were sintered under a temperature of (800oC) for a period of (120 hr) and a heating rate of (10oC / min) in order to ensure a gradual diffusion process between the atoms and obtain a bonded substance and to produce the optimal stability of high phase formation (Pb-1223). X-ray diffraction analysis was performed for the pure and partially substituted sample, and it was observed that all samples contain a high percentage of high phase (Pb-1223) in addition to some other phases with some few impurities at the end of the chart and an increase in the intensity of the high phase peaks (Pb-1223) and decrease in the intensity of the remaining phase peaks compared to the pure sample. It turns out that the sample (x=0.15) possesses the highest percentage of the high phase (Pb-1223), which represents the ideal sample in this group in terms of the replacement ratio. The surface of these systems was also analyzed using atomic force microscopy (AFM). [ABSTRACT FROM AUTHOR]