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Computers, Materials & Continua 2023年第4期75卷 1253-1269页

作者： waleed aldosari Department of Computer Engineering College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia

This paper presents a machine-learning method for detecting jamming UAVs and classifying nodes during jamming attacks onWireless Sensor Networks(WSNs).Jamming is a type of Denial of Service(DoS)attack and intentional interference where a malicious node transmits a high-power signal to increase noise on the receiver side to disrupt the communication channel and reduce performance *** defend and prevent such attacks,the first step is to detect *** current detection approaches use centralized techniques to detect jamming,where each node collects information and forwards it to the base *** a result,overhead and communication costs *** this work,we present a jamming attack and classify nodes into different categories based on their location to the jammer by employing a single node *** a result,we introduced a machine learning model that uses distance ratios and power received as features to detect such ***,we considered several types of jammers transmitting at different power levels to evaluate the proposed metrics using *** a detection accuracy of 99.7%for the k-nearest neighbors(KNN)algorithm and average testing accuracy of 99.9%,the presented solution is capable of efficiently and accurately detecting jamming attacks in wireless sensor networks.

关键词： Jamming attacks machine learning unmanned aerial vehicle(UAV) WSNs

Synthesis, characterization, biological activities and luminescent properties of lanthanide complexes with [2-thiophenecarboxylic acid, 2-(2-pyridinylmethylene)hydrazide] Schiff bases ligand

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Journal of Rare Earths 2016年第10期34卷 986-993页

作者： Abdulaziz M.Ajlouni Qutaiba Abu-Salem Ziyad A.Taha Ahmed K.Hijazi waleed al Momani Department of Applied Chemical Sciences Jordan University of Science and Technology Department of Chemistry Faculty of Science Al al-Bayt University Department of Basic Medical Sciences Faculty of Medicine Yarmouk University

A Schiff base L [2-thiophenecarboxylic acid, 2-（2-pyridinylmethylene）hydrazide] with its lanthanide metal complexes was synthesized. These complexes were characterized by elemental analysis, molar conductivity measurements, spectral analysis（NMR, FT-IR, and UV-Vis）, luminescence and thermal gravimetric analysis. The Schiff base ligand was a tridentate chelate and coordinates to the central lanthanide ion with 1：2 metal：ligand ratio. The conductivity data showed a 1：1 electrolytic nature with a general formula [LnL_2（NO_3）_2]NO_3. The luminescence emission properties for Sm, Tb, and Eu complexes were observed and showed that the ligand L could absorb and transfer energy to Sm（III）, Tb（III） and Eu（III） ions. The complexes possessed a good antibacterial activity against different bacterial strains. In addition, the scavenging activity of the Ln（III） complexes on DPPH was concentration dependant and the complexes were significantly more efficient in quenching DPPH than the free Schiff base ligand.

关键词： hydrazone lanthanides complexes luminescence properties antibacterial activity rare earths

Deep Learning Based Efficient Crowd Counting System

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Computers, Materials & Continua 2024年第6期79卷 4001-4020页

作者： waleed Khalid al-Ghanem Emad Ul Haq Qazi Muhammad Hamza Faheem Syed Shah Amanullah Quadri Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh12372Saudi Arabia Centre of Excellence in Cybercrime and Digital Forensics Naif Arab University for Security SciencesRiyadh14812Saudi Arabia Center of Excellence for Information Assurance(COEIA) King Saud UniversityRiyadh12372Saudi Arabia

Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different *** is challenging to determine the approximate crowd size from an image of the crowd’s *** in this research study,we proposed a multi-headed convolutional neural network architecture-based model for crowd counting,where we divided our proposed model into two main components:(i)the convolutional neural network,which extracts the feature across the whole image that is given to it as an input,and(ii)the multi-headed layers,which make it easier to evaluate density maps to estimate the number of people in the input image and determine their number in the *** employed the available public benchmark crowd-counting datasets UCF CC 50 and ShanghaiTech parts A and B for model training and testing to validate the model’s *** analyze the results,we used two metrics Mean Absolute Error(MAE)and Mean Square Error(MSE),and compared the results of the proposed systems with the state-of-art models of crowd *** results show the superiority of the proposed system.

关键词： Crowd counting EfficientNet multi-head attention convolutional neural network transfer learning

Precision time protocol attack strategies and their resistance to existing security extensions

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Cybersecurity 2021年第1期4卷 160-176页

作者： waleed alghamdi Michael Schukat School of Computer Science National University of Ireland Galway Ireland

The IEEE 1588 precision time protocol(PTP)is very important for many industrial sectors and applications that require time synchronization accuracy between computers down to microsecond and even nanosecond ***,PTP and its underlying network infrastructure are vulnerable to cyber-attacks,which can stealthily reduce the time synchronization accuracy to unacceptable and even damage-causing levels for individual clocks or an entire network,leading to financial loss or even physical *** security protocol extensions only partially address this *** paper provides a comprehensive analysis of strategies for advanced persistent threats to PTP infrastructure,possible attacker locations,and the impact on clock and network synchronization in the presence of security protocol extensions,infrastructure redundancy,and protocol *** distinguishes between attack strategies and attacker types as described in RFC7384,but further distinguishes between the spoofing and time source attack,the simple internal attack,and the advanced internal *** experiments were conducted to demonstrate the impact of PTP *** analysis shows that a sophisticated attacker has a range of methodologies to compromise a PTP ***,all PTP infrastructure components can host an attacker,making the comprehensive protection of a PTP network against a malware infiltration,as for example exercised by Stuxnet,a very tedious task.

关键词： APT Cyber-attacks IEEE 1588 PTP Security Time synchronization protocols

Neoproterozoic U-Th-REE-bearing Pegmatites in Wadi Ibib, South Eastern Desert, Egypt: Structural and Geochemical Measures for a Syn-Tectonic Anatectic Model of Formation

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 2045-2062页

作者： waleed S.IBRAHIM Nuclear Materials Authority El MaadiCairoEgypt

The Wadi Ibib area is situated in the northern part of the Neoproterozoic Hamisana Shear Zone(HSZ), which is a high strain zone evolved during the late stages of the Pan-African orogeny, likely as a tectonic escape structure. Amphibolite facies pelitic metasedimentary windows crop out in the axial parts of the HSZ and are noticeably associated with numerous N-trending pegmatite dikes. Whole-rock geochemistry of the pegmatites reveals a peraluminous(S-type) affinity, with low K/Rb ratios and elevated concentrations of U, Th, REE, Rb, Li, Cs, Y, Nb and Ta. Structurally, the pegmatite sets intrude along the shear plane of the HSZ, corresponding to the regional N-trending tectonic fabrics, such as axial planar foliation and dextral-shearing in the metasedimentary host rock. Field relationships, including structural context, coupled with geochemical characteristics of the Wadi Ibib pegmatites, do not support their formation as a complementary part of evolved granitic magmas. Space-localized decompression-induced partial melting of peraluminous garnet-bearing metapelites was alternatively the underlying process for formation of these pegmatites. Such decompression was associated with regional escape tectonics and stress axes permutations during the late deformation stage(D3) in the evolution of the south Eastern Desert terrane, due to end-orogeny system pressure-release.

关键词： U-Th-REE mineralization anataxis pegmatite origin Hamisana Shear Zone Wadi Ibib Egypt

Multidrug resistance Acinetobacter species at the intensive care unit,Aseer Central Hospital,Saudi Arabia:A one year analysis

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Asian Pacific Journal of Tropical Medicine 2016年第9期9卷 881-885页

作者： ali al Bshabshe Martin R.P.Joseph ali al Hussein waleed Haimour Mohamed E.Hamid Department of Medicine College of MedicineKing Khalid University Department of Microbiology College of MedicineKing Khalid University Intensive Care Unit Aseer Central Hospital Microbiology Laboratories Aseer Central Hospital

Objective:To identify and to determine the antimicrobial susceptibility of Acinetobacter baumannii(***) clinical isolates from ICU at Aseer Central ***:The study was conducted in the Intensive Care Unit,Aseer Central Hospital,Saudi Arabia over 13 months period(2014-2015).Acinetobacter species(n= 105) were isolated from various clinical *** were identified using selected phenotypic criteria and confirmed using the Vitek 2 automated *** system was used to determine the susceptibilities of 21 antimicrobial ***,isolates and drug data were analyzed using the SPSS statistical software package to determine some epidemiological and microbiological ***:Of the 105 stains,*** accounted for 49(46.67%),*** complex,19(18.09%),***/haemolyticus 32(30.47),Acinetobacter haemolyticus 4(3.81%),Acinetobater lwoffii 1(0.95%) and unidentified Acinetobater species 2(1.3%).Of the 105 Acinetobacter strains,103(98.1%) were found multidrug resistant(MDR).*** strain were 100% sensitive to colistin and 74.5% to trimethoprim + *** remaining 19 antimicrobial agents revealed low or no sensitivities:amikacin 16.3%; ampicillin 7.7%; ceftazidime 7.3%.Distribution of similar sensitivities was shown by other Acinetobacter *** number of isolates from males and females indicates no statistical variation(P=0.867) whereas age groups showed significant differences(P= 0.008) as it is clear from the high percentage of infected individuals more than 60 years followed by those aged 20 to 29 years old(19.05%).Upper respiratory tract(30.48%),lower respiratory tract(47.65%) and subcutaneous tissue(9.5%) were the main sources of Acinetobacter *** mean numbers of isolates from these specimens indicate no discrepancy between specimens(P=0.731).Conclusions:Acinetobacterspecies including *** were found MDR(98.1%) according to the current Acinetobacter *** categorization.A

关键词： Acinetobacter spp. ICU Antimicrobials Aseer Central Hospital

Adaptive 3D descattering with a dynamic synthesis network

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Light(Science & Applications) 2022年第5期11卷 766-786页

作者： waleed Tahir Hao Wang Lei Tian Department of Electrical and Computer Engineering Boston UniversityBostonMA 02215USA Department of Biomedical Engineering Boston UniversityBostonMA 02215USA

Deep learning has been broadly applied to imaging in scattering applications.A common framework is to train a descattering network for image recovery by removing scattering *** achieve the best results on a broad spectrum of scattering conditions,individual“expert”networks need to be trained for each ***,the expert’s performance sharply degrades when the testing condition differs from the *** alternative brute-force approach is to train a“generalist”network using data from diverse scattering *** generally requires a larger network to encapsulate the diversity in the data and a sufficiently large training set to avoid ***,we propose an adaptive learning framework,termed dynamic synthesis network(DSN),which dynamically adjusts the model weights and adapts to different scattering *** adaptability is achieved by a novel“mixture of experts”architecture that enables dynamically synthesizing a network by blending multiple experts using a gating *** demonstrate the DSN in holographic 3D particle imaging for a variety of scattering *** show in simulation that our DSN provides generalization across a continuum of scattering *** addition,we show that by training the DSN entirely on simulated data,the network can generalize to experiments and achieve robust 3D *** expect the same concept can find many other applications,such as denoising and imaging in scattering ***,our dynamic synthesis framework opens up a new paradigm for designing highly adaptive deep learning and computational imaging techniques.

关键词： network scattering synthesis

Seismic performance of high-rise buildings in selected regions in Saudi Arabia according to different seismic codes

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 179-191页

作者： Sayed Mahmoud Mohamed alsearheed waleed Abdallah Department of Civil and Construction Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Building Engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Civil Engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The design code for each country is revised and updated based on an expected zone’s seismic intensities,geotechnical site classifications,structural systems,construction materials and methods of construction in order to provide more realistic considerations of seismic demand,seismic response,and seismic *** on the aforementioned provisions,structures designed according to different seismic codes may yield different performances for the same level of *** study aims to investigate and compare the induced responses related to the earthquake-resistant design of reinforced concrete(RC)buildings according to the Saudi building code(SBC-301),American code(ASCE-7),uniform building code(UBC-97),and European code(EC-8).In order to account for the provision regarding the hazard specification and its effect on the induced seismic responses,four regions in the Kingdom of Saudi Arabia with different seismic levels are *** code provisions related to the specification of site classification and its effect on the induced design base shear are investigated as *** differences are observed in the induced responses with the variation in seismic design codes for the considered seismic hazards and site classifications.

关键词： high-rise building SBC-301 international seismic codes seismic zones site classifications

Liver transplantation for hepatitis B virus: Decreasing indication and changing trends

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World Journal of Gastroenterology 2015年第26期21卷 8140-8147页

作者： waleed al-hamoudi Hussien Elsiesy Abdulrahman Bendahmash Nasser al-masri Safiyya ali Naglaa allam Mohammed al Sofayan Hamad al Bahili Mohammed al Sebayel Dieter Broering Sammy Saab Faisal Abaalkhail Gastroenterology Unit Department of MedicineCollege of MedicineKing Saud University Department of Liver Transplantation and Hepatobiliary Surgery King Faisal Specialist Hospital and Research Center National Liver Institute Menoufeya University David Geffen School of Medicine UCLA

AIM: To evaluate the indication and outcome of hepatitis B virus(HBV)-related liver transplantation(LT) in the era of newer antiviral ***: We collected data on all patients who underwent transplantation at King Faisal Specialist Hospital and Research *** data included demographic,perioperative and long-term postoperative follow-up data including viral serological markers,HBV DNA,and repeated liver *** January 1990 and January 2012,133 patients(106 males and 27 females) underwent LT for HBV-related cirrhosis at our *** patients were followed up frequently during the first year following transplantation,according to our standard protocol; follow-up visits occurred every 3-6 mo *** infection was definedas re-emergence of HBV-DNA or hepatitis B surface antigen(HBs Ag) while on *** patients transplanted prior to 1992 did not receive immediate posttransplant anti-HBV prophylaxis; all other patients were treated with HBIG and at least one nucleos(t)ide ***: One hundred and thirty-three patients underwent LT for HBV and were followed for a median of 82 mo(range: 1-274).The rates of post-LT survival and HBV recurrence during the follow-up period were 89% and 11%,*** following factors were associated with disease recurrence: younger age(44.3 ± 16.2 years vs 51.4 ± 9.9 years,P = 0.02),positive pretransplant hepatitis B e antigen(HBe Ag)(60% vs 14%,P al of 64 transplants were performed,including 46(72%) for decompensated HBV cirrhosis,12(19%) for decompensated cirrhosis complicated by HCC and 6(10%) for compensated cirrhosis complicated by ***

关键词： Hepatitis B Hepatitis C Non-alcoholicsteatohepatitis Liver transplantation Hepatocellularcarcinoma

Sudden death in the southern region of Saudi Arabia:A retrospective study

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World Journal of Clinical Cases 2023年第20期11卷 4843-4851页

作者： Ahmed Mohamed Ahmed al-Emam Abdulrahman Dajam Mohammed alrajhi waleed alfaifi Mubarak al-Shraim Ahmed Mohamed Helaly Department of Pathology College of MedicineKing Khalid UniversityAsir 61421Saudi Arabia Forensic Medicine and Clinical Toxicology Mansoura UniversityMansoura 35516Egypt Medical School King Khalid UniversityAsir 61421Saudi Arabia Clinical Science Faculty of MedicineYarmouk UniversityIrbid 21163Jordan

BACKGROUND Sudden death is unanticipated,non-violent death taking place within the first 24 h after the onset of *** is a major public health problem ***,the effects of living at moderate altitude on mortality are poorly *** To retrospectively report the frequency and the main causes of sudden deaths in relation to total deaths at Asir Central Hospital,2255 m above sea level,in the southern region of Saudi Arabia over a period of 4 years from 2013 to *** The medical records of 1821 deaths were examined and showed 353 cases(19.4%)of sudden *** The highest incidence of sudden death was among the elderly(51%),whereas,the lowest was among children and adolescents(6.5%).With regard to gender,the incidence of sudden death was higher in males(54.4%)compared to 45.6% in *** this study,we found that the most common direct causes of sudden death were cardiovascular diseases(29.2%),respiratory disease(22.7%),infectious disease(12.2%),cancer(9.4%)and hematological diseases(6.2%).With respect to seasonal variation,the highest incidence was during winter(31.32%)followed by summer(25.8%).CONCLUSION The results of this study will help emergency physicians and health care providers to exercise due care to reduce the incidence of sudden death and raise public awareness about the impact of sudden death.

关键词： Sudden death High altitude Cardiovascular Gender distribution Age Seasonal variation