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How Do V2V and V2I Messages Affect the Performance of Driving Smart Vehicles?

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Computer Systems Science & Engineering 2023年第11期47卷 2313-2336页

Intelligent transportation systems(ITSs)are becoming increasingly popular as they support efficient coordinated *** aim to improve the safety,efficiency and reliability of road transportation through integrated approaches to the exchange of relevant *** adhoc networks(MANETs)and vehicle ad-hoc networks(VANETs)are integral components of *** VANET is composed of interconnected vehicles with sensitivity capabilities to exchange traffic,positioning,weather and emergency *** of the main challenges in VANET is the reliable and timely dissemination of information between vehicular nodes to improve decision-making *** paper illustrates challenges in VANET and reviews possible solutions to improve road safety control and management using V2V and V2I *** paper also summarizes existing rules-based and optimized-based solutions,including reducing the effect of mixed environments,obstacles,malfunctions and short wireless ranges on transportation efficiency and reducing false messages that cause unintended vehicle actions and unreliable transportation ***,an event simulation algorithm was designed to maximize the benefits of exchangeable messages among ***,simulated VANET environments were developed to demonstrate how the algorithm can be used for transformable *** results show that coupling of both V2V and V2I messages yielded better results in terms of end-to-end delay and average *** research directions were highlighted to be taken into account in the development of ITS and intelligent routing mechanisms.

关键词： Vehicle-to-vehicle vehicle-to-infrastructure transport systems

Morphological and Phylogenetic Studies of a Copepod Species, Irodes parupenei Ho and Lin (2007), Infecting Parupeneus rubescens in Saudi Arabia

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Journal of Ocean University of China 2022年第2期21卷 457-464页

作者： DKHIL Mohamed A ALHAFIDH Wejdan AL-QURAISHY Saleh ALOTAIBI Mashael BANAEEM Manal alsaleh Thekra ABDEL-GABER Rewaida Department of Zoology College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Dammam City is one of the gorgeous coastal areas in the Arabian Gulf of Saudi *** present study aimed to ex-amine one of the copepod species infecting the rosy goatfish that represents a highly consumed fish species by the local population in the Arabian *** copepod species isolated from the infected fish specimens belong to the family Taeniacanthidae and was iden-tified as Irodes parupenei Ho and Lin(2007),primarily based on its morphological,morphometric,and ultrastructural characteris-tics,especially the structures of the dorsal cephalic area,segmentation of the first antenna,the absence of the maxilliped claw in the fe-male specimens,and the setation and spinulation of the legs 2-4 for the adult females are of great significance in the taxonomic *** 18S rRNA gene sequence was analyzed to ensure the precise identity and exact taxonomic status of the copepod *** result showed that this copepod species belong to Taenicanthidae and closely related to Irodes sauridi(gb|JF781550.1)in the same *** details on the specificity of the goatfish for Irodes species and identifying these parasitic taxa using molecular analysis are given in the present study.

关键词： Taenicanthidae Irodes species goatfish parasite specificity 18S rRNA gene

Experimental and theoretical investigations of the lateral vibrations of an unbalanced Jeffcott rotor

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 1024-1032页

作者： Ali alsaleh Hamid MSEDIGHI Hassen MOUAKAD Saudi Arabian Oil Company(ARAMCO) Dhahran 31311Saudi Arabia Mechanical Engineering Deparment Faculty of EngineeringShahid Chamran University of AhvazAhvaz 61357-43337Iran Drilling Center of Excellence and Research Shahid Chamran University of AhvazAhvaz 61357-43337Iran Mechanical and Industrial Engineering Deparment Sultan Qaboos UniversinAI Khoudh MuscatOman

The current work experimentally explores and then theoretically examines the lateral vibrations of an unbalanced Jeffcott rotor-system working at several unbalance *** this end,three conditions of eccentric masses are considered by using a Bently Nevada RK-4 rotor *** of the steady-state as well as the startup data at rigid and flexible rotor states are captured by conducting a setup that mimics the vibration monitoring industrial *** linear governing equation of the considered rotor is extracted by adopting the Lagrange method on the basis of rigid rotor assumptions to theoretically predict the lateral *** dynamic features of the rotor system such as the linearized bearing induced stiffness are exclusively acquired from startup *** is demonstrated that,with an error of less than 5%,the proposed two-degrees-of-freedom model can predict the flexural vibrations at rigid *** at flexible condition,it fails to accurately predict the dynamic *** contrast to the other works where nonlinear mathematical models with some complexities are proposed to mathematically model the real systems,the present study illustrates the applicability of employing simple models to predict the dynamic response of a real rotor-system with an acceptable accuracy.

关键词： rotor-dynamics Jeffcott rotor lateral vibrations Lagrange method system-equivalent stfess sleeve bearings il film induced stiffness

Strength and Wear Behavior of Mg Alloy AE42 Reinforced with Carbon Short Fibers

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 31-40页

作者： Sabbah Ataya Naser A.alsaleh Mohamed M.El-Sayed Seleman Metallurgical and Materials Engineering Department Faculty of Petroleum and Mining Engineering Suez University Department of Mechanical Engineering College of Engineering Al Imam Mohammad Ibn Saud University

In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of Mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(Mg–Al–Mn—RE; rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. Materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the Mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the Mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions.

关键词： Magnesium composites Carbon short fibers Compressive strength Wear resistance Wear mechanisms

Evaluation of Infection Prevention and Control Programmes (IPC), and Assessment Tools for IPC-Programmes at MOH-Health Facilities in Saudi Arabia

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Open Journal of Nursing 2014年第7期4卷 483-492页

作者： abdullah M. Assiri Abdul Jamil Choudhry Suhair S. alsaleh Khalid H. Alanazi Suha S. alsaleh Department of Medicine King Fahad Medical City Riyadh KSA Imam Abdulrahman bin Faisal Hospital Dammam-National Guard Health Affairs Dammam KSA Ministry of Health Riyadh KSA

Infection Prevention and Control is a Quality Standard and is crucial in all health care facilities. Many hospitals remain deficient in trained infection control professionals (ICPs), and now there is an acute awareness of the need to correct this shortfall. The objectives of the study were to describe the current status of ICP programs at ministry of health (MOH) and to evaluate the current status of infection prevention and control programs at health care facilities in kingdom of Saudi Arabia. A cross sectional interview and a self assessment study were conducted on infection prevention and control (IPC) program in Saudi Arabia. All the MOH hospital in all regions was randomly chosen to the study setting. The selection of facilities was done at random with a clear intention to include twenty regions. A random sample was taken from these hospitals with sample size 56 (55.4%), by Multi stage random sampling technique. Results showed that the total facility in all over the kingdom was 51.4% where central area covered the facility score 58.2%, followed by western area (54.8%), south (53.7%), east (46.3%), and lastly with (45.8%) north area. Survey revealed that the infrastructure for infection control program in Saudi Arabian hospitals remained underdeveloped. There were defects in the identified components of effective infection control programs.

关键词： Infection Prevention Control Assessment Tools Health Facility Saudi Arabia

Calculation of the Zeeman-Fine Energies and the Spectrum with Doppler-Shift Correction of Atomic Lithium

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Journal of Modern Physics 2011年第7期2卷 752-758页

作者： Laila Babsail Leda Bousiakou Salwa alsaleh Mesude Saglam 不详

We have calculated the Zeeman-fine energies of atomic Lithium (Li) by using the varying effective Landé g-factor method. We take the principle quantum number in the range;(2 ≤n ≤10 ). For this range we find 26 different energy values and 325 wavelengths some of which are the same. The Doppler shift is found to be Δλ=±0.004λ. The Doppler shift-corrected wavelengths are in perfect agreement with the observed (NIST) values for atomic Li.

关键词： Hydrogen-Like Atoms Effective Landé G-Factor Quantum Entanglement Zeeman-Fine Energies Photonic Transitions Quantum Flux Of Photon