One of the key challenges is reliable communication for Unmanned Underwater Vehicles (UUVs) since underwater environments are dynamic and challenging for signal transmission. The traditional acoustic communication systems allow long-distance communication but are limited by the low bandwidth, high latency, and doppler effect. Optical wireless, on the other hand, provides high data rates with water absorption and scattering occurring within the transmission distance, but has a short range of communication. To overcome these drawbacks, a smart hybrid optical-acoustic communication system is proposed that is a combination of Wavelength Division Multiplexing and On-Off Keying (WDM-OOK) to transmit a high-speed signal over optical and acoustic channels to achieve high reliability of long-range communication. The design of an intelligent hybrid optical–acoustic communications network to improve the continuity, reliability, and throughput of the communication between a UUV system is the focus of this research. It is a combination of a simple model of Multilayer Perceptron (MLP), a real-time communication mode switch, an optical subsystem (Wavelength Division Multiplexing On–Off Keying (WDM-OOK)), and an acoustic communication subsystem. The system has been modelled and simulated in MATLAB/Simulink and synthesized in HDL Coder as it will be implemented on an FPGA (Kintex-7 325T). The results of the simulations validate the superiority of the proposed hybrid method (hybrid with AI) over the purely optical method, the purely acoustic method, and the hybrid method without AI. The minimum BER recorded on this platform was (10-7), the average throughput was 152 Mbps, and the end-to-end latency time was 12.7ms with good water clarity. The FPGA synthesis results also show that the model was appropriate for real-time implementation with only 18.1% of the LUTs, 10.5% of the flip-flops, 23.6% of the BRAMs, and 17.4% of the DSPs utilized for the Kintex-7 325T FPGA. The results verified the feasibility of the proposed hybrid optical–acoustic communication system, where the high-speed feature of using the optical communication WDM-OOK system and the robustness of the acoustic communication system are provided by the intelligent adaptive switching. The proposed framework is feasible and is scalable for underwater reliable real-time communication between unmanned optical vehicles (UOVs) in underwater unmanned vehicle networks (UUVnets) in the near future.
Background: In this study we evaluate the effect of plasma treatment (oxygen and argon) gas in two different exposure times on the surface of heat cure and light cure acrylic resin. Materials and method: 100 specimens of heat cure and light cure acrylic resin were fabricated. The measurements of the samples were (75mm, 25mm and 4.5mm) length, width and depth respectively with stopper of 3mm depth. Two types of gas used oxygen and argon in (5,10) min by using (DC-glow discharge plasma device) then we apply cold cure soft lining material, with the help of Instron machine we test the shear stress value. Results: A highly significant effect after argon and oxygen gases treatment in both 5 and 10 min exposure times on shear bond strength to soft
... Show MoreThe aim of this study was to evaluate the effects of local application of bisphosphonate gel and recombinant human bone morphogenic protein 2 gel, on titanium dental implant stability and marginal bone level. Twenty-seven patients with upper and lower missing posterior tooth/teeth were included in the study with a total of 71 implants that were used for rehabilitation. The implants were randomly divided into 4 groups: 3 study groups and 1 control. Group1; local application of bisphosphonate gel, group 2; local application of recombinant human bone morphogenic protein 2 gel, group 3; local application of a mixed formula of both gels. The gel application was immediately preimplant insertion, group 4; implant insertion without application of a
... Show MoreNaturally available products have been used widely for centuries in handling human disease. The present study aimed to determine the effect of aluminum potassium sulfate addition into the soft liner on tensile strength and peel bond strength. The effect of aluminum potassium sulfate evaluated by two methods, first one include incorporation of KAL (SO4)2 into soft liner monomer in concentration (2%,3% by wt.) while the second method include immersion of soft liner specimens in solution of KAL(SO4)2 in concentration(5%,10% percent) during time periods (0,10 minutes). In conclusions, the results of current study encourage use KAL (SO4)2 within soft liner material
The development of the world, and in light of the intensity of competition highlighted the need to research and create a sustainable competitive advantage is sustained from an internal source in the company earned by the scarcity and difficulty of imitation by competitors, and this source is green innovation. In order to achieve the objective of the research, which is the diagnosis and analysis of the relationship between green innovation (in products, processes) and sustainable competitive advantage in the group of companies Kronji, was developed a default model of the research reflects the nature of the relationship and influence among its variables, the research adopted the questionnaire as a key tool for collecting data and i
... Show MoreLas formas verbales: el infinitivo, el gerundio y el participio, son derivados verbales que se comportan como sustantivos, adverbios o adjetivos, respectivamente; aunque, dado su carácter verbal pueden también funcionar como verbos y, por tanto, como núcleos del predicado.
El presente trabajo presenta una visión general sobre las formas no personales del verbo en español. Se debe recordar que las formas no personales del verbo tiene funciones y valores dentro de la oración.
Este trabajo lo dividimos en dos partes: la primera presenta un breve marco teórico en que se explica las formas no personales del verbo y como se forman además de sus funciones.
Abstract
... Show MoreThis research is devoted to the effect of investigation of the ZnO content on the structural and electrical properties of (NiO)1-x (ZnO)x films prepared by pulsed laser precipitation on the glass substrate at room temperature. Thin-film (NiO)1-x (ZnO)x sediments were deposited with different composition ratios where x = 0, 0.2, 0.4, 0.6 and 1.0 with a thickness of n150nm. The diffraction pattern for X-ray analysis reveals that the structure of the prepared thin films is identical with the cubic phase and hexadecimal stage of x = 0 and 0.1, respectively while the structure is mixed with the remaining x
François Mauriac’s novel The Desert of Love (1949) puts the reader before an experienced sociologist who is skillfully able to analyze the most mysterious human emotions and feelings. The writer's starting point is that people are similar in feelings but different in behavior. He severely criticized the aristocratic class and uncovered its defects and faults.
The novelist presents Courege's family as an example of the aristocratic class. It is a family torn by hatred, selfishness and disagreements due to absence of intimacy and love. This poisoned environment pushes the father and his son, Raymond, to search away for emotional ventures and banned relations
... Show MorePsoriasis is a chronic inflammatory condition that requires effective treatment. Genetic variability, particularly in the Tumour Necrosis Factor-alpha (TNF-α) gene, may influence patients’ response to biological therapies such as etanercept. This study evaluated the association of four TNF-α gene polymorphisms (rs361525 G/A, rs673 G/A, rs1800629 G/A, and rs1800750 G/A) with serum TNF-α levels and response to etanercept in Iraqi patients with psoriasis. A retrospective study was conducted on 80 patients with moderate-to-severe psoriasis who received etanercept for at least six months. Patients were categorised as responders (≥ 75% PASI reduction) or non-responders (≤ 50% PASI reduction). Genotyping was performed using PCR and
... Show MoreThe Southern Cowpea Beetle Callosobruchus maculatus (F.) is one of the most widespread insect pests of stored legumes, causing a considerable loss during storage, decreasing the net weight of the crops, and resulting in reduced the quality of the crops. This study has been conducted to determine the lifetime, fertility and life table parameters of C. maculatus by using an alkaloids extract from Moringa oleifera leaves at different concentrations 1000, 2000, and 3000 ppm. The result was shown that the lowest survival rate was 49% at a concentration of 1000, 2000 ppm, as compared with the control which was 77%. The lowest reproductive rate (Ro) was 4.76 female/female/generation at the concentration of 1000 ppm, c
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