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Effect of (Ba_(0.6)Sr_(0.4))TiO_3(BST) Doping on Dielectric Properties of CaCu_3Ti_4O_(12)(CCTO)

Journal of Materials Science & Technology 2012年第12期28卷 1137-1144页

作者： I. Norezan a.k. yahya M.k. Talari Faculty of Applied Sciences Universiti Teknologi MARAShah Alam Selangor Malaysia

The effect of （Ba（0.6）Sr（0.4））TiO3（BST） addition on dielectric properties of CaCu3Ti4O（12）（CCTO） ceramic was investigated. Ceramic samples with the chemical formula （1-x）CaCu3Ti4O（12）＋ x（Ba（0.6）,Sr（0.4））TiO3 （x=0, 0.05, 0.1, and 0.2） were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy （SEM） investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO （x=0） showed la.k.of stability with frequency which dropped drastically between 104 and 105Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ～104 range for all doped samples. The dielectric loss （tanδ） of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary （E（gb）） showed higher values as compared to the activation energy of grains （Eg ） for all samples and conforms to the internal barrier layer capacitor （IBLC） model.

关键词： CaCu3Ti4O(12)(CCTO) Dielectric properties (Ba(0.6)Sr(0.4))TiO3(BST)

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Changes in climatic conditions drive variations in arbuscular mycorrhizal fungi diversity and composition in semi-arid oak forests

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Journal of Forestry Research 2024年第5期35卷 106-119页

作者： Nahid Jafarian Javad Mirzaei Reza Omidipour yahya kooch Department of Forest Science Faculty of AgricultureIlam UniversityIlam 69315-516Iran Department of Range and Watershed Management Faculty of AgricultureIlam UniversityIlam 69315-516Iran Faculty of Natural Resources and Marine Sciences Tarbiat Modares UniversityNoor 46417-76489MazandaranIran

Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem ***,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid *** this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were *** findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer *** pH had the highest correlation with different facets of AMF *** equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil *** on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical *** outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical *** addition,with increasing dryness,sporulation and AMF diversity increased.

关键词： AMF diversity and composition Physiographic factors Semi-arid ecosystems Zagros forest

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Phenolic Profile and Volatiles of in vitro Propagated Lavandula angustifolia ***

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 427-444页

作者： Mir Abdullatif yahya Fatma Tunali Dilek killi Atalay Sökmen Biotechnology Department Konya Food and Agriculture UniversityKonya42080Türkiye Plant Production and Technologies Department Konya Food and Agriculture UniversityKonya42080Türkiye

An effective in vitro propagation protocol was designed for Lavandula angustifolia Miller,a medicinal aromatic plant that is a prominent source of volatile organic compounds(VOCs).Murashige and Skoog media were supplemented with various concentrations of Plant Growth Regulators(PGRs),and the growth parameters of the nodal segments were *** explants formed callus when they were supplemented with 2 mg/L of 6-Benzylaminopurine(BAP).The superior hormonal concentration of Murashige and Skoog(MS)media for the proliferation of shoots from callus cultures(39.33%)was 5 mg/L of 2-Isopentenyl adenine(2iP),and the favorable media for the growth of *** callus cultures was 1 and 2 mg/L of BAP,with a 98%for-mation rate in each *** callus cultures and in vitro propagated *** seedlings obtained from var-ious PGR concentrations of MS media were exposed to qualitative and quantitative analysis in terms of phenolic proﬁles,ﬂavonoids,High-performance liquid chromatography(HPLC)analysis of phenolic acids,and headspace-SPME analysis for *** analysis revealed that micropropagated seedlings grown in media containing 1 mg/L of 6-Furfurylaminopurine(kIN)accumulated the highest yield(11.95±0.01 mg GAE/g)of phenolic *** contrast,the lowest concentration(2.17±0.04 mg GAE/g)was detected in 0.5 mg/L of BAP+0.5 mg/L of Naphthaleneacetic acid(NAA)*** plantlets grown in 0.5 mg/L of BAP+0.5 mg/L of NAA media showed the highestﬂavonoid yield(31.67±0.06μg/g QE/g).In contrast,callus samples exhibited the lowest yield(11.59±0.02μg/g QE/g)ofﬂavonoids in MS media supplemented with a concentration of 0.5 mg/L of *** analysis revealed the variability of phenolic acid contents within the callus cultures as well as plantlets,with gallic acid,4-OH benzoic acid,chlorogenic acid,vanillic acid,caffeic acid,cinnamic acid,and rosmarinic acid being the prominent *** presence of twenty-two chemicals was revealed by headspace-SPME ***

关键词： Lavender indirect organogenesis micropropagation This

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Computational Approach for Automated Segmentation and Classification of Region of Interest in Lateral Breast Thermograms

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Computers, Materials and Continua 2024年第3期80卷 4749-4765页

作者： Tsietso, Dennies yahya, Abid Samikannu, Ravi Qureshi, Basit Babar, Muhammad Department of Electrical Computer and Telecommunications Engineering Botswana International University of Science and Technology Private Bag 16 Palapye Botswana College of Computer and Information Sciences Prince Sultan University Riyadh 11586 Saudi Arabia Robotics and Internet of Things Lab Prince Sultan University Riyadh 11586 Saudi Arabia

Breast cancer is one of the major health issues with high mortality rates and a substantial impact on patients and healthcare systems worldwide. Various Computer-Aided Diagnosis (CAD) tools, based on breast thermograms, have been developed for early detection of this disease. However, accurately segmenting the Region of Interest (ROI) from thermograms remains challenging. This paper presents an approach that leverages image acquisition protocol parameters to identify the lateral breast region and estimate its bottom boundary using a second-degree polynomial. The proposed method demonstrated high efficacy, achieving an impressive Jaccard coefficient of 86% and a Dice index of 92% when evaluated against manually created ground truths. Textural features were extracted from each view’s ROI, with significant features selected via Mutual Information for training Multi-Layer Perceptron (MLP) and k-Nearest Neighbors (kNN) classifiers. Our findings revealed that the MLP classifier outperformed the kNN, achieving an accuracy of 86%, a specificity of 100%, and an Area Under the Curve (AUC) of 0.85. The consistency of the method across both sides of the breast suggests its viability as an auto-segmentation tool. Furthermore, the classification results suggests that lateral views of breast thermograms harbor valuable features that can significantly aid in the early detection of breast cancer. Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： k-nearest neighbors

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Classifying Modulations in Communication Intelligence Using Deep Learning Networks

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Journal of Systems Science and Information 2024年第3期12卷 379-392页

作者： yahya BENREMDANE Said JAMAL Oumaima TAHERI Jawad LAkZIZ Said OUa.k.T Department of Physics Faculty of Science Ben M'sikUniversity HassanⅡCasablanca 20100Morocco

The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal *** a result,the work we performed involved selecting the database required for supervised deep learning,evaluating the performance of current techniques on unprocessed communication signals,and suggesting a deep learning networkbased method that would enable the classification of modulation types with the best possible ratio between computation time and *** started by examining the automatic classification models that are currently in *** light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensemble learning strategy based on adjusted Res Net and Transformer Neural Network,which is effective at extracting multi-scale features from the raw I/Q sequence ***,we produced an architecture that is simple to use and apply to communication *** architecture of this solution is strong and optimal,enabling it to determine the type of modulation with up to 95%accuracy automatically.

关键词： automatic modulation classification artificial intelligence deep learning radio frequency electronicwarfare

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Optimizing Connections:Applied Shortest Path Algorithms for MANETs

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 787-807页

作者： Ibrahim Alameri Jitka.k.ma.k.va Tawfik Al-Hadhrami Abdulsamad Ebrahim yahya Atef Gharbi Faculty of Medical Sciences Jabir Ibn Hayyan Medical UniversityAlkufaNajaf54001Iraq Faculty of Economics and Administration University of PardubiceStudentskaPardubice53210Czech Republic Computer Science Department School of Science and TechnologyNottingham Trent UniversityNottinghamNG118NSUK Department of Information Technology College of Computing and Information TechnologyNorthern Border UniversityArar91431Saudi Arabia Department of Information System College of Computing and Information TechnologyNorthern Border UniversityArar91431Saudi Arabia

This study is trying to address the critical need for efficient routing in Mobile Ad Hoc Networks(MANETs)from dynamic topologies that pose great challenges because of the mobility of *** objective was to delve into and refine the application of the Dijkstra’s algorithm in this context,a method conventionally esteemed for its efficiency in static ***,this paper has carried out a comparative theoretical analysis with the Bellman-Ford algorithm,considering adaptation to the dynamic network conditions that are typical for *** paper has shown through detailed algorithmic analysis that Dijkstra’s algorithm,when adapted for dynamic updates,yields a very workable solution to the problem of real-time routing in *** results indicate that with these changes,Dijkstra’s algorithm performs much better computationally and 30%better in routing optimization than Bellman-Ford when working with configurations of sparse *** theoretical framework adapted,with the adaptation of the Dijkstra’s algorithm for dynamically changing network topologies,is novel in this work and quite different from any traditional *** adaptation should offer more efficient routing and less computational overhead,most apt in the limited resource environment of ***,from these findings,one may derive a conclusion that the proposed version of Dijkstra’s algorithm is the best and most feasible choice of the routing protocol for MANETs given all pertinent key performance and resource consumption indicators and further that the proposed method offers a ma.k.d improvement over traditional *** paper,therefore,operationalizes the theoretical model into practical scenarios and also further research with empirical simulations to understand more about its operational effectiveness.

关键词： Dijkstra’s algorithm optimization complexity analysis shortest path first comparative algorithm analysis nondeterministic polynomial(NP)-complete

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Enhancing Network Design through Statistical Evaluation of MANET Routing Protocols

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Computers, Materials & Continua 2024年第7期80卷 319-339页

作者： Ibrahim Alameri Tawfik Al-Hadhrami Anjum Nazir Abdulsamad Ebrahim yahya Atef Gharbi Faculty of Medical Sciences Jabir ibn Hayyan Medical UniversityAlkufa QuNajaf54001Iraq Computer Science Department School of Science and TechnologyNottingham Trent UniversityNottinghamNG118NSUK Department of Computing Faculty of Engineering Sciences&Technology(FEST)Hamdard UniversityKarachi74600Pakistan Department of Information Technology College of Computing and Information TechnologyNorthern Border UniversityArar91431Saudi Arabia Department of Information System College of Computing and Information TechnologyNorthern Border UniversityArar91431Saudi Arabia

This paper contributes a sophisticated statistical method for the assessment of performance in routing protocols salient Mobile Ad Hoc Network(MANET)routing protocols:Destination Sequenced Distance Vector(DSDV),Ad hoc On-Demand Distance Vector(AODV),Dynamic Source Routing(DSR),and Zone Routing Protocol(ZRP).In this paper,the evaluation will be carried out using complete sets of statistical tests such as kruskal-Wallis,Mann-Whitney,and *** articulates a systematic evaluation of how the performance of the previous protocols varies with the number of nodes and the mobility *** study is premised upon the Quality of Service(QoS)metrics of throughput,pa.k.t delivery ratio,and end-to-end delay to gain an adequate understanding of the operational efficiency of each protocol under different network *** findings explained significant differences in the performance of different routing protocols;as a result,decisions for the selection and optimization of routing protocols can be taken effectively according to different network *** paper is a step forward in the general understanding of the routing dynamics of MANETs and contributes significantly to the strategic deployment of robust and efficient network infrastructures.

关键词： Routing protocols statistical approach friedman MANET

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3D-Printed MOF Monoliths:Fabrication Strategies and Environmental Applications

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Nano-Micro Letters 2024年第12期16卷 358-405页

作者： Hossein Molavi kamyar Mirzaei Mahdi Barjasteh Seyed yahya Rahnamaee Somayeh Saeedi Aliakbar Hassanpouryouzband Mashallah Rezakazemi Department of Chemistry Institute for Advanced Studies in Basic Science(IASBS)Zanjan 45137-66731Iran Department of Chemical and Biological Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA Center for Nano-Science and Nanotechnology Institute for Convergence Science&TechnologySharif University of TechnologyTehran 15614Iran Department of Biomedical Engineering Amirkabir University of Technology(Tehran Polytechnic)Hafez Ave.P.O.Box 15875-4413TehranIran Grant Institute School of GeosciencesUniversity of EdinburghWest Main RoadEdinburgh EH93FEUK Faculty of Chemical and Materials Engineering Shahrood University of TechnologyShahroodP.O.Box ***Iran

Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,tha.k. to their large specific surface area,high porosity,tailorable structures and compositions,diverse functionalities,and well-controlled pore/size ***,most developed MOFs are in powder forms,which still have some technical challenges,including abrasion,dustiness,low pa.k.ng densities,clogging,mass/heat transfer limitation,environmental pollution,and mechanical instability during the pa.k.ng process,that restrict their applicability in industrial ***,in recent years,attention has focused on techniques to convert MOF powders into macroscopic materials like beads,membranes,monoliths,gel/sponges,and nanofibers to overcome these ***-dimensional(3D)printing technology has achieved much interest because it can produce many high-resolution macroscopic frameworks with complex shapes and geometries from digital ***,this review summarizes the combination of different 3D printing strategies with MOFs and MOF-based materials for fabricating 3D-printed MOF monoliths and their environmental applications,emphasizing water treatment and gas adsorption/separation ***,the various strategies for the fabrication of 3D-printed MOF monoliths,such as direct ink writing,seed-assisted in-situ growth,coordination replication from solid precursors,matrix incorporation,selective laser sintering,and digital light processing,are described with the relevant ***,future directions and challenges of 3D-printed MOF monoliths are also presented to better plan future trajectories in the shaping of MOF materials with improved control over the structure,composition,and textural properties of 3D-printed MOF monoliths.

关键词： MOFs 3D-printing Environmental remediation Shaping Monoliths

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Enhanced asphalt dynamic modulus prediction: A detailed analysis of artificial hummingbird algorithm-optimised boosted trees

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Journal of Road Engineering 2024年第2期4卷 224-233页

作者： Ikenna D.Uwanuakwa Ilham yahya Amir Lyce Ndolo Umba Department of Civil Engineering Near East UniversityMersin 10Turkey Faculty of Sciences University of LubumbashiLubumbashiThe Democratic Republic of Congo

This study introduces and evaluates a novel artificial hummingbird algorithm-optimised boosted tree(AHAboosted)model for predicting the dynamic modulus(E*)of hot mix asphalt *** a substantial dataset from NCHRP Report-547,the model was trained and rigorously *** metrics,specifically RMSE,MAE,and R2,were employed to assess the model's predictive accuracy,robustness,and *** benchma.k.d against well-established models like support vector machines(SVM)and gaussian process regression(GPR),the AHA-boosted model demonstrated enhanced *** achieved R2 values of 0.997 in training and 0.974 in testing,using the traditional Witczak NCHRP 1-40D model *** features such as test temperature,frequency,and asphalt content led to a 1.23%increase in the test R2,signifying an improvement in the model's *** study also explored feature importance and sensitivity through SHAP and permutation importance plots,highlighting binder complex modulus|G*|as a.k.y *** the AHA-boosted model shows promise,a slight decrease in R2 from training to testing indicates a need for further ***,this study confirms the AHA-boosted model as a highly accurate and robust tool for predicting the dynamic modulus of hot mix asphalt concrete,making it a valuable asset for pavement engineering.

关键词： Asphalt Dynamic modulus Prediction Artificial hummingbird algorithm Boosted tree

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A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： Muhammed S.PARANCHEERIVILa.k.THIL Jafar S.PILa.k.DAN Rafic M.AJAJ Mohammadreza AMOOZGAR Davood ASADI yahya ZWEIRI Michael I.FRISWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies Morphing aircraft Shape morphing Flight dynamics Aeroelasticity

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