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Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： M.K.h.Hamad Nidal Dwaikat M.H.A.Mhareb M.I.Sayyed R.M.Hamad Y.S.M.Alajerami M.A.Almessiere Gameel Saleh ahmad hussein alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear Medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia Medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&Minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOM computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding Mass stopping power Rare earths

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Investigating the Relevance of Arabic Text Classification Datasets Based on Supervised Learning

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Journal of Electronic Science and Technology 2022年第2期20卷 187-208页

作者： ahmad hussein Ababneh the Computer Science Department American University of MadabaMadaba 2882

Training and testing different models in the field of text classification mainly depend on the pre-classified text document datasets. Recently, seven datasets have emerged for Arabic text classification, including Single-Label Arabic News Articles Dataset(SANAD), Khaleej, Arabiya, Akhbarona, KALIMAT, Waten2004, and Khaleej2004. This study investigates which of these datasets can provide significant training and fair evaluation for text classification(TC). In this investigation, well-known and accurate learning models are used, including naive Bayes(NB), random forest(RF), K-nearest neighbor(KNN), support vector machines(SVM), and logistic regression(LR) models. We present relevance and time measures of training the models with these datasets to enable Arabic language researchers to select the appropriate dataset to use based on a solid basis of comparison. The performances of the five learning models across the seven datasets are measured and compared with the performances of the same models trained on a well-known English language dataset. The analysis of the relevance and time scores shows that training the SVM model on Khaleej and Arabiya obtained the most significant results in the shortest amount of time,with the accuracy of 82%.

关键词： shortest enable neighbor

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Imbalanced Data Classification Using SVM Based on Improved Simulated Annealing Featuring Synthetic Data Generation and Reduction

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Computers, Materials & Continua 2023年第4期75卷 547-564页

作者： hussein Ibrahim hussein Said Amirul Anwar Muhammad Imran ahmad Department of Computer Techniques Engineering AlSafwa University CollegeKarbala56001Iraq Faculty of Electronic Engineering&Technology Universiti Malaysia PerlisArau02600PerlisMalaysia

Imbalanced data classification is one of the major problems in machine *** imbalanced dataset typically has significant differences in the number of data samples between its *** most cases,the performance of the machine learning algorithm such as Support Vector Machine(SVM)is affected when dealing with an imbalanced *** classification accuracy is mostly skewed toward the majority class and poor results are exhibited in the prediction of minority-class *** this paper,a hybrid approach combining data pre-processing technique andSVMalgorithm based on improved Simulated Annealing(SA)was ***,the data preprocessing technique which primarily aims at solving the resampling strategy of handling imbalanced datasets was *** this technique,the data were first synthetically generated to equalize the number of samples between classes and followed by a reduction step to remove redundancy and duplicated *** is the training of a balanced dataset using *** this algorithm requires an iterative process to search for the best penalty parameter during training,an improved SA algorithm was proposed for this *** this proposed improvement,a new acceptance criterion for the solution to be accepted in the SA algorithm was introduced to enhance the accuracy of the optimization *** works based on ten publicly available imbalanced datasets have demonstrated higher accuracy in the classification tasks using the proposed approach in comparison with the conventional implementation of *** at an average of 89.65%of accuracy for the binary class classification has demonstrated the good performance of the proposed works.

关键词： Imbalanced data resampling technique data reduction support vector machine simulated annealing

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Preparation and Properties of Poly(vinyl alcohol)/Chitosan Blend Bio-nanocomposites Reinforced by Cellulose Nanocrystals

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Chinese Journal of Polymer Science 2014年第12期32卷 1620-1627页

作者： Susan Azizi Mansor Bin ahmad Nor Azowa Ibrahim Mohd Zobir hussein Farideh Namvar Department of Chemistry Faculty of Science University Putra Malaysia Materials Synthesis and Characterization Laboratory Institute of Advanced Technology University Putra Malaysia Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia Mashhad Branch Islamic Azad University

The aim of this paper is to report the effect of the addition of cellulose nanocrystals（CNCs） on the mechanical, thermal and barrier properties of poly（vinyl alcohol）/chitosan（PVA/Cs） bio-nanocomposites films prepared through the solvent casting process. The characterizations of PVA/Cs/CNCs films were carried out in terms of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, thermogravimetric analysis（TGA and DTG）, oxygen transmission rate（OTR）, and tensile tests. TEM and SEM results showed that at low loading levels, CNCs were dispersed homogenously in the PVA/Cs matrix. The tensile strength and modulus in films increased from 55.1 MPa to 98.4 MPa and from 395 MPa to 690 MPa respectively, when CNCs content went from 0 wt% to 1.0 wt%. The thermal stability and oxygen barrier properties of PVA/Cs matrix were best enhanced at 1.0 wt% of CNCs loading. The enhanced properties attained by incorporating CNCs can be beneficial in various applications.

关键词： Bio-nanocomposite Poly(vinyl alcohol)/chitosan Cellulose nanocrystals Mechanical properties Thermal properties.

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Copper oxide nanoparticles-loaded zeolite and its characteristics and antibacterial activities

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Journal of Materials Science & Technology 2017年第8期33卷 889-896页

作者： Abdullah A.Alswat Mansor Bin ahmad Mohd Zobir hussein Nor Azowa Ibrahim Tawfik A.Saleh Department of Chemistry Faculty of ScienceUniversiti Putra MalaysiaSelangor 43400Malaysia Department of Chemistry Sana'a UniversityYemen Department of Chemistry King Fahcl University of Petroleum&MineralsDhahran 31261Saudi Arabia

In the present work, a simple and green co-precipitation method was used to prepare copper oxide-zeolite nanocomposites（CuO-zeolite NCs）. The weight ratio（1, 3, 5, 8 and 10 wt%） of CuO nanoparticles（NPs）loaded into zeolite was investigated to obtain the optimum CuO distribution for antibacterial *** prepared CuO-zeolite NCs were characterized by ultraviolet-visible（UV–vis） spectroscopy, Fourier transform infrared（FT-IR） spectroscopy, powder X-ray diffraction（XRD）, and energy dispersive X-ray fluorescence spectrometry（EDXRF）. The transmission electron microscopy（TEM） and field emission scanning electron microscopy（FE-SEM） revealed a uniform surface morphology of the CuO-zeolite *** UV–vis spectrum of NCs showed absorption peaks between 230 and 280 nm for nano-CuO in the XRD patterns, and new peaks appeared between（36.56？–38.83？） related to the CuO. At weight ratio less than 10 wt%, the CuO nanoparticles loaded to the zeolite exhibited spherical shapes with average particle diameter of 6.5 nm measured by TEM and XRD. Antibacterial activities were tested against Gram-negative and Gram-positive bacteria. The obtained results showed that, CuO-zeolite NCs with 8 wt% CuO nanoparticles had the highest antibacterial activities against Bacillus Subtilis B29 and Salmonella Choleraesuis ATCC10708, which can be attributed to the good dispersion of CuO NPs on the zeolite surface.

关键词： Copper oxide-zeolite Nanocomposites Antibacterial

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包裹式土工格栅-砂土相互作用对条形基础承载力-沉降特性的影响研究

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岩土力学 2022年第9期43卷 2550-2567页

作者： ahmad hussein MAHBOUBI ahmad NOORZAD Ali HOSEINI Mohammad Hosein 蒂什林大学土木工程学院岩土工程学系拉塔基亚叙利亚沙希德·贝赫什提大学土木、水和环境工程学院德黑兰伊朗

高质量材料的使用以及土层的处理是保持建筑结构稳定并保证其设计寿命的重要因素,尤其是在垫层较差的地区。对未加筋、土工格栅加筋和折叠土工格栅加筋细砂上方的条形基础进行试验研究,以评估平面土工格栅层数、折叠土工格栅在土中的位... 详细信息

高质量材料的使用以及土层的处理是保持建筑结构稳定并保证其设计寿命的重要因素,尤其是在垫层较差的地区。对未加筋、土工格栅加筋和折叠土工格栅加筋细砂上方的条形基础进行试验研究,以评估平面土工格栅层数、折叠土工格栅在土中的位置、土工格栅折叠层的厚度、折叠土工格栅的搭接长度、土工格栅折叠层的间距以及土工格栅的层数等因素的影响。与平面土工格栅加筋砂相比,折叠土工格栅加筋砂在静载作用下的性能更好。此外,在基础下方一定深度处存在一个临界区域。在该区域内,折叠土工格栅会导致基础沉降量增加。这一临界区域会影响较小基础宽度处的砂土特性。试验结果表明,折叠土工格栅的最优埋置深度为基础宽度的0.41,厚度为基础宽度的0.20。增加折叠土工格栅的层数可以明显减少沉降比。该试验表明,包裹式加筋可以显著提高结构框架的承载能力,减少沉降,并使得它们可以在狭小的空间中使用。

关键词：土工合成材料条形基础包裹式土工格栅平面土工格栅砂土承载力沉降特性

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Improved Reptile Search Algorithm by Salp Swarm Algorithm for Medical Image Segmentation

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Journal of Bionic Engineering 2023年第4期20卷 1766-1790页

作者： Laith Abualigah Mahmoud Habash Essam Said Hanandeh ahmad MohdAziz hussein Mohammad Al Shinwan Raed Abu Zitar Heming Jia Computer Science Department Prince Hussein Bin Abdullah Faculty for Information TechnologyAl Al-Bayt UniversityMafraq25113Jordan Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman19328Jordan Faculty of Information Technology Middle East UniversityAmman11831Jordan Applied Science Research Center Applied Science Private UniversityAmman11931Jordan School of Computer Sciences Universiti Sains Malaysia11800Pulau PinangMalaysia Amman Arab University AmmanJordan Department of Computer Information System Zarqa UniversityP.O.Box 13132ZarqaJordan Deanship of E-Learning and Distance Education Umm Al-Qura UniversityMakkah21955Saudi Arabia Faculty of Information Technology Applied Science Private UniversityAmman11931Jordan Sorbonne Center of Artificial Intelligence Sorbonne University-Abu DhabiAbu DhabiUnited Arab Emirates School of Information Engineering Sanming UniversitySanming365004China

This study proposes a novel nature-inspired meta-heuristic optimizer based on the Reptile Search Algorithm combed with Salp Swarm Algorithm for image segmentation using gray-scale multi-level thresholding,called *** proposed method introduces a better search space to find the optimal solution at each ***,we proposed RSA-SSA to avoid the searching problem in the same area and determine the optimal multi-level *** obtained solutions by the proposed method are represented using the image *** proposed RSA-SSA employed Otsu’s variance class function to get the best threshold values at each *** performance measure for the proposed method is valid by detecting fitness function,structural similarity index,peak signal-to-noise ratio,and Friedman ranking *** benchmark images of COVID-19 validate the performance of the proposed *** results showed that the proposed RSA-SSA outperformed other metaheuristics optimization algorithms published in the literature.

关键词： Bioinspired Reptile Search Algorithm Salp Swarm Algorithm Multi-level thresholding Image segmentation Meta-heuristic algorithm

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Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam:Litsea elliptica,Dillenia suffruticosa,Dillenia excelsa,Aidia racemosa,Vitex pinnata and Senna alata

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Asian Pacific Journal of Tropical Biomedicine 2017年第2期7卷 173-180页

作者： May Poh Yik Goh Aida Maryam Basri Hartini Yasin hussein Taha Norhayati ahmad Environmental and Life Sciences Faculty of ScienceUniversiti Brunei DarussalamJalan Tungku LinkGadong BE1410Brunei Darussalam Herbal Drug Discovery Laboratory Faculty of ScienceUniversiti Brunei DarussalamJalan Tungku LinkGadong BE1410Brunei Darussalam Chemical Sciences Faculty of ScienceUniversiti Brunei DarussalamJalan Tungku LinkGadong BE1410Brunei Darussalam

The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata. The known phytochemical constituents of these plants and their ability to bring about a range of biological activities are included in this review. These plants have been used traditionally for a multitude of diseases and illnesses. There is a lot of untapped potential in these medicinal plants which could cure multiple diseases.

关键词： Litsea elliptica Dillenia suffruticosa Dillenia excelsa Aidia racemosa Vitex pinnata Senna alata

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Pancreaticoduodenectomy in the Middle East: Achieving optimal results through specialization and standardization

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 478-483页

作者： Walid Faraj hussein Nassar ahmad Zaghal Deborah Mukherji Ali Shamseddine Mariam Kanso Rola F. Jaafar Mohamad Khalife Liver Transplantation and Hepatopancreaticobiliary Surgery Department of General SurgeryAmerican University of Beirut Medical CenterBeirutLebanon Department of Oncology American University of Beirut Medical CenterBeirutLebanon

Background: Pancreaticoduodenectomy is a challenging surgical intervention that remains the cornerstone in the treatment of localized peri-ampullary pathologies. The concept of treatment standardization has been well-established in many high-volume centers in the world. Here, we present our experience in pancreaticoduodenectomy from 1994 to 2015. Methods: We performed a retrospective review of the medical charts of patients who underwent pancreaticoduodenectomy at our institution. Data was entered to SPSS statistical software and analyzed. The Mann-Whitney U and Fisher’s exact tests were used to report statistical differences between groups. Results: Of the 370 patients who underwent pacreaticoduodenectomy, 300 were analyzed. The 1-, 3-, 5- and 10-year survival rates were 85%, 35%, 15%, and 7%, respectively with a 30-day mortality rate of 5.0%(15 patients). The median age of the patients was 61 (13-84) years, with 193 (64.3%) males and 107 (35.7%) females. The median operative time was 300 (130-570) min. The median postoperative length of hospital stay was 12 (5-76) days. Thirty-two patients required re-laparotomies;10 for pancreatic leak, 7 for biliary leak and 15 for control of bleeding. Seventy-five (25.0%) patients developed pancreatic fistulae. Delayed gastric emptying was present in 31 (10.3%) patients. A significant improvement in surgical outcome was observed in cases done after 2008 which indicates the important role of specialized team in surgical management. Conclusions: The number of patients undergoing pancreaticoduodenectomy has been increasing annually over the past twenty-two years in our institution with results comparable to published series from high-volume centers. Through standardization of surgical techniques and perioperative management carried out by a specialist team, our results continue to improve despite the increasing complexity of cases referred to our unit.

关键词： Pancreatic cancer Pancreaticoduodenectomy Middle East

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Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras

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Asian Pacific Journal of Tropical Biomedicine 2013年第7期3卷 542-548页

作者： hussein Farhan Hassan Rammal Akram Hijazi ahmad Daher Mohamad Reda hussein Annan Ali Chokr Ali Bassal Bassam Badran Doctoral School of Science and Technology Research Platform for Environmental Science Lebanese UniversityLebanon Faculty of Agricultural and Veterinary Sciences Lebanese UniversityLebanon Faculty of Sciences-1- Lebanese UniversityLebanon

Objective:To determine the chemical composition,total phenolic and total flavonoid contents ofthe crude extracts from leaves and stems of a Lebanese plantEuphorbia macroclada schyzoceras(***),and to evaluate their antioxidant potential using DPPH,H2O2,and chelating offerrous ions ***:Quantification of the total phenolic and total flavonoid contents ofthe crude extracts from leaves and stems and the antioxidant activities were evaluated usingspectrophotometric *** chemical composition has been estimated using differenttechniques such as IR,LC/MS and ***:Ethanolic extract from leaves *** was better than aqueous extract and showed higher content in total phenolic and total flavonoidthan found in the *** the other hand,using DPPH and H2O2tests,this extract from leavesshowed higher antioxidant capacity than aqueous ***,using the chelating of ferrousions test,the antioxidant activity of the aqueous extract of both stems and leaves was strongerthan that of ethanolic *** chemical composition of the whole plant showed the presence ofsome aromatic compounds and fatty ***:Both ethanolic and water extracts fromboth parts of this plant are effective and have good antioxidant ***,this plant can be usedin the prevention of a number of diseases related to oxidative stress.

关键词： Euphorbia macroclada schyzoceras Total phenolic Total flavonoid Antioxidant potential Chemical composition

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