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Optical properties and radiative rates of Nd^(3+) doped zinc-sodium phosphate glasses

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Journal of Rare Earths 2019年第3期37卷 253-259页

作者： A.A.El-Maaref Shimaa Badr Kh.S.shaaban E.A.abdel Wahab M.M.ElOkr Physics Department Faculty of Science Al-Azhar University Modern Academy for Engineering & Technology Chemistry Department Faculty of Science Al-Azhar University

Preparation using melt quenching technique and optical characterizations of Nd^(3+) doped Zn-Na phosphate glasses are presented. The structure of the present glasses was studied using X-ray diffraction and FT-IR spectroscopy. UV-vis spectra of the present glasses were analyzed at different concentrations of Nd_2 O_3. The effect of neodymium concentration on the density and energy band gap was investigated. The density of the present glasses slightly increases with the increasing of Nd_2 O_3. A small variation of energy band gap with the increasing of neodymium content is observed as well, while E_g values decrease with the increase of Nd_2 O_3 content. The E_g values lie between 4.36 and 4.69 eV. Based on the measured optical spectra, Judd-Ofelt theory was used to determine the optical parameters such as line strengths, optical intensity parameters(Ω_t), transition probabilities, and transition lifetimes. Hypersensitive transitions were identified in the absorption spectrum, the greatest line strengths are recorded at the transitions^2 G_(7/2)+ ~4 G_(5/2), ~4 S_(3/2) + ~4 F_(7/2) and ~4 D_(1/2) + ~4 D_(3/2)+ ~4 D_(5/2) + ~2 I_(11/2) with wavelengths of 580, 475 and 355 nm,respectively. Lifetimes of the important ~4 F_(3/2) laser-level were determined; which show decreasing trend with the increasing of Nd_2 O_3 content and are found to be between 0.838 and 1.595 ms. The uncertainty of the present results was estimated. The RMS deviations were determined, which show lower values than those in the literature.

关键词： Phosphate glass UV-vis spectroscopy Judd-Ofelt Radiative rates Rear earth ions

Joint Optimal Power Source Sizing and Data Collection Trip Planning for Advanced Metering Infrastructure Enabled by Unmanned Aerial Vehicles

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1337-1348页

作者： Haiam Shahin Mostafa F.shaaban Mahmoud H.Ismail Hebat-Allah M.Mourad Ahmed Khattab Department of Electronics and Communications Engineering Facultyof EngineeringCairo UniversityGiza 12613Egypt IEEE Department of Electrical Engineering American University of SharjahPOBox 26666SharjahThe United Arab Emirates

The use of unmanned aerial vehicles(UAVs) in the collection of data from wireless devices, sensor nodes, and the Internet of Things(IoT) devices has recently received significant attention. In this paper, we investigate the data collection process from a set of smart meters in advanced metering infrastructure(AMI) enabled by UAVs. The objective is to minimize the total annual cost of the electric utility by jointly optimizing the number of UAVs, their power source sizing, the charging locations as well as the data collection trip planning. This is achieved while considering the energy budgets of batteries of UAVs and the required amount of collected data. The problem is formulated as a mixed-integer nonlinear programming(MINLP), which is decoupled into two sub-problems where a candidate UAV and a number of buildings are first grouped into trips via genetic algorithms(GAs), and then the optimum trip path is found using a traveling salesman problem(TSP) branch and bound algorithm. Simulation results show that the battery capacity or the number of UAVs increases as the coverage area or the density increases.

关键词： Advanced metering infrastructure unmanned aerial vehicle power source sizing trip planning genetic algorithm

Optimizing biochar addition for vermicomposting:a comprehensive evaluation of earthworms’activity,N_(2)O emissions and compost quality

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Biochar 2023年第1期5卷 59-70页

作者： Yupeng Wu Qinfen Li Yong Zheng Xingjun Xiong Yunfeng Chen Muhammad shaaban Ronggui Hu College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China Institute of Environment and Plant Protection Chinese Academy of Tropical Agricultural SciencesHaikou 571158China Power China Kunming Engineering Corporation Limited Kunming 650051China Institute of Plant Protection and Soil Fertilizer Hubei Academy of Agricultural SciencesWuhan 430064China Department of Soil Science Bahauddin Zakariya UniversityMultan 60800Pakistan

Biochar addition has been widely used in the field to mitigate soil nitrous oxide(N_(2)O)emissions,and can be considered as a potential method to reduce N_(2)O emissions during ***,excessive biochar addition may inhibit earthworms’***,it is crucial to clarify the optimum addition volumes of biochar during *** study evaluated the impact of addition of various amounts of biochar(0,5,10,15,20 and 25%of total amount of feedstock)on earthworms’(Eisenia fetida)activity,N_(2)O emission and compost quality during *** with the treatment without biochar added,5%of biochar application significantly increased earthworm total biomass(from 177.5 to 202.2 g pot^(−1)),and cumulative burrowing activity(from 47.0%to 52.2%pixel per terrarium).The increased earthworms activity stimulated the vermicomposting process and led to the best quality of compost,which showed the highest total nutrient content(5.38%)and a significantly higher germination percentage of seeds(88%).Although N_(2)O emissions were slightly increased by 5%biochar addition,a nonsignificant difference was found between the treatment with 5%biochar and the treatment without biochar *** the contrary,20%and 25%biochar addition not only lowered N_(2)O emissions,but also significantly decreased the quality of *** results suggest that 5%biochar application is an appropriate amount to improve the quality of compost without significant N_(2)O emissions.

关键词： Earthworm Biochar addition Nitrous oxide Functional genes Burrowing activity

Volumetric Assessment of Corticospinal Tract Infiltration by Astrocytoma Using Diffusion Tensor Tractography

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Open Journal of Medical Imaging 2014年第2期4卷 65-71页

作者： Marwa Adel shaaban Taha Kamel Alloush Mohamed Hamdy Ibrahim Ahmed abd el bar Sherif Hashim Morad Department of Neurology Ain Shams University Cairo Egypt Department of Neurosurgery Ain Shams University Cairo Egypt Department of Radiology Misr University for Science and Technology Cairo Egypt

Objectives: The aim of the study is to assess volumetric Corticospinal Tract infiltration by Astro-cytoma using Diffusion Tensor Tractography. Material and Methods: Preoperative, anatomic (T1- and T2-weighted) and diffusion tensor MRI were performed in 9 patients with supratentorial gliomas (WHO grade II and III). The tumors were manually segmented from the T1- and T2-weighted MRI, and their volume calculated. A three-dimensional tractography was performed in each case. A second segmentation and volume measurement was performed on the tumor regions intersecting adjacent white matter fiber tracts. Results: We identified that white matter tracts were infiltrated by 6 Astrocytoma tumors. The median tumor volume (±standard deviation) in our patient population was 33 ± 26.82 ml. The median tumor volume (±standard deviation) infiltrating white matter fiber tracts was 4.15 ± 9.23 ml. The median fraction of tumor volume infiltrating white matter fiber tracts was 26.3% ± 10.1%. Conclusions: Diffusion tensor MR Tractography is a reliable preoperative assessment tool since it detects extensive white matter infiltration by Astrocytoma irrespective of brain tumors volume. Recommendations: Prospective large population studies are required to clarify how infiltration relates to tumor location.

关键词： Tractography Astrocytoma Brain Tumor Corticospinal Tract Infiltration

Shape classification based on singular value decomposition transform

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重庆邮电大学学报（自然科学版） 2009年第2期21卷 246-252页

作者： shaaban Zyad ARIF Thawar BABA Sami KREKOR Lala Faculty of Information Technology Applied Science University Amman 11931 Jordan

In this paper, a new shape classification system based on singular value decomposition (SVD) transform using nearest neighbour classifier was proposed. The gray scale image of the shape object was converted into a black and white image. The squared Euclidean distance transform on binary image was applied to extract the boundary image of the shape. SVD transform features were extracted from the the boundary of the object shapes. In this paper, the proposed classification system based on SVD transform feature extraction method was compared with classifier based on moment invariants using nearest neighbour classifier. The experimental results showed the advantage of our proposed classification system.

关键词：奇异值分解形状分类分解变换分类系统欧氏距离变换特征提取黑白图像近邻分类

Watermarking of Digital Images in Frequency Domain

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International Journal of Automation and computing 2010年第1期7卷 17-22页

作者： Sami E. I. Baba Lala Z. Krikor Thawar Arif Zyad shaaban Faculty of Information Technology Applied Science UniversityAmmanJordan

Invisible watermarking methods have been applied in frequency domains, trying to embed a small image inside a large original image. The original bitmap image will be converted into frequency domain to obtain the discrete cosine transform （DCT） matrices from its blocks. The bits of the logo image are embedded in random color components of the original image, as well as in random positions in each selected block. These positions are alternating current （AC） coefficients of the DCT matrix. The randomness is obtained from RC4 pseudorandom bit generator that determines in which color component this logo image bits will be embedded. The embedded bits have been hidden in random blocks in the image, which are chosen according to a （semi-random） function proposed in this work.

关键词： Watermarking discrete cosine transform (DCT) pseudorandom bit generator RC4 JPEG

Fat grafting in autologous breast reconstruction:applications,outcomes,safety,and complications

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Plastic and Aesthetic Research 2023年第1期10卷 485-500页

作者： Bahaa shaaban David Guerrero Carolyn De La Cruz Lauren Kokai Department of Plastic Surgery University of PittsburghPittsburghPA 15213USA University of Pittsburgh Medical Center PittsburghPA 15213USA Department of Bioengineering University of PittsburghPittsburghPA 15213USA McGowan Institute for Regenerative Medicine PittsburghPA 15213USA

Autologous fat grafting is an important surgical technique in aesthetic and reconstructive *** grafting for breast reconstruction is now an established procedure for adding volume and improving cutaneous pliability;it can be used independently to replace more invasive flap procedures or implants,or as an adjunct for smaller volume *** breadth of applications in the breast necessitates diversity in technique and approach,and while there is no universally agreed-upon protocol,basic principles have guided the evolution of some commonly adopted ***,fat grafting outcomes are highly favorable but dependent on patient and procedure factors,requiring learned patient selection and expertise in recipient site *** complications from fat grafting,such as fat necrosis and the development of nodules,are particularly troublesome for post-oncologic patients,requiring considerable pre-surgical consultation for patient education and managing *** addition to volume and contour augmentation,fat grafting has additional beneficial effects that have recently drawn increased attention including pain reduction from implant capsular contracture or postmastectomy pain syndrome,improved skin quality and reduced fibrosis following radiation,and possible anti-tumorigenic *** developments in clinical fat grafting research that are promising include the use of adipose progenitor cells admixed with lipoaspirate for improved volume retention or alternative biologics such as platelet-rich ***,research towards safe and effective regenerative medicine approaches is actively underway,with the ultimate goal of achieving predictable and increased graft retention,reducing the number of required surgical procedures and enabling on-table results to reflect procedure outcomes.

关键词： Fat grafting fat transfer autologous breast reconstruction implant reconstruction lipo-injection breast augmentation graft survival skin expansion mastectomy post-mastectomy pain breast fibrosis capsular contracture

Novel markers of endothelial dysfunction in hepatitis C virus-related cirrhosis: More than a mere prediction of esophageal varices

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World Journal of Hepatology 2020年第10期12卷 850-862页

作者： Amr shaaban Hanafy Mohamed abdel Khalik Basha Fady Maher Wadea Department of Internal Medicine Gastroenterology and Hepatology DivisionZagazig University HospitalZagazig 44519Egypt Department of Diagnostic Radiology Zagazig UniversityZagazig 44519Egypt

BACKGROUND Hepatitis C virus(HCV)infection may affect lipid metabolism by enhancing the circulating levels of inflammatory cytokines,together with its impact on endothelial *** To evaluate the potential correlation of changes in lipid profile,carotid intimamedia thickness(CIMT),and ankle-brachial index with the severity of fibrosis,grades of esophageal varices(EVs),and fibrosis *** The study included 240 subjects who were divided into 3 groups;group 1(n=90,HCV-related cirrhotic patients with EVs),group 2(n=90,HCV-related cirrhotic patients without EVs),and group 3(n=60,served as the healthy control group).All patients underwent routine laboratory tests,including a lipid profile ***-density lipoproteins(LDL)/platelet count and platelet/splenic diameter ratios were *** ultrasonography,CIMT by carotid Doppler,bedside ankle-brachial index(ABI),liver stiffness measurement,and upper gastrointestinal endoscopy were *** Multivariate logistic regression revealed that very-low-density lipoprotein(VLDL)(β=0.988,odds ratio 2.5,P=0.001),LDL/platelet count ratio(β=1.178,odds ratio 3.24,P=0.001),CIMT(β=1.37,odds ratio 3.9,P=0.001),and ABI(β=2.3,odds ratio 5.9,P=0.001)were the key variables associated with significant fibrosis,EVs and endothelial *** and LDL/platelet count ratio were predictive of advanced fibrosis and EVs at cutoff values of 1.1 mm and 1 mm,respectively,with an area under the curve(AUC)of 0.966 and 0.960(P=0.001),while VLDL and ABI at a cutoff of 16.5 mg/dL and 0.94 were predictive of advanced fibrosis and EVs with an AUC of 0.891 and 0.823,respectively(P=0.001).CONCLUSION CIMT,ABI,VLDL,LDL/platelet count ratio are good non-invasive predictors of advanced fibrosis,presence of EVs,and endothelial dysfunction in liver cirrhosis.

关键词： Lipid profile Liver cirrhosis Esophageal varices Carotid-intima media thickness Ankle-brachial index

橡胶木屑基活性炭—聚氨酯复合材料的制备及其微波吸收性能（英文）

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新型炭材料 2015年第2期30卷 167-175页

作者： Azizah shaaban Sian-Meng Se Imran Mohd Ibrahim Qumrul Ahsan Department of Engineering Materials Faculty of Manufacturing EngineeringUniversiti Teknikal Malaysia Melaka (UTeM) Hang Tuah Jaya 76100 Durian Tunggal Melaka Malaysia Department of Telecommunication Faculty of Electronics and Computer EngineeringUniversiti Teknikal Malaysia Melaka (UTeM) Hang Tuah Jaya 76100 Durian Tunggal Melaka Malaysia

采用ZnCl2对橡胶木屑进行化学活化制备出活性炭。ZnCl2与橡胶木屑的浸渍质量比为1.0-2.0,活化温度为500℃,时间为60min。通过扫描电镜、X射线衍射和BET比表面分析仪探讨浸渍比例对活性炭孔结构的影响。结果表明,当浸渍比为1.5∶1时,样... 详细信息

采用ZnCl2对橡胶木屑进行化学活化制备出活性炭。ZnCl2与橡胶木屑的浸渍质量比为1.0-2.0,活化温度为500℃,时间为60min。通过扫描电镜、X射线衍射和BET比表面分析仪探讨浸渍比例对活性炭孔结构的影响。结果表明,当浸渍比为1.5∶1时,样品的比表面积和孔径分别为1301m2/g和0.37cm3/g。通过化学发泡工艺将不同质量分数(1%,2%,3%,5%,8%)的活性炭填充至聚氨酯中制备出聚氨酯复合材料。在1-5GHz频率范围内,复合材料吸收微波。随着活性炭含量增加,在1-3GHz范围内,介电常数(ε’)和回波损耗增加。活性炭含量为8%时复合材料的介电常数达到最大值3.0。在1.8GHz时,复合材料的回波损耗为10dB。在-2.5GHz,电磁屏蔽效率大于3dB。与传统聚合物材料如填加金属的聚氨酯和聚酯相比,所制复合材料呈微波段吸收,可作为电磁屏蔽材料。

关键词：橡胶木屑化学活化活性炭微波吸收材料介电常数回波损耗