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Digital Communications and Networks 2019年第3期5卷 183-188页

作者： Sherif K. el Dyasti Esam A.A. Hagras hadia el-hennawy Ain Shams Cairo Egypt elec and Comm. Dept Technical Research Centre Cairo Egypt Faculty of Engineering Ain Shams Cairo Egypt

Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng Division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving Division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity.

关键词： Interleaver Division Multiplexing (IDM) Multiple Input Multiple Output (MIMO) Spatial Modulation (SM) Quadrature Spatial Modulation (QSM)

Approximate electromagnetic Cloaking of a Dielectric Sphere Using Homogeneous Isotropic Multi-Layered Materials

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Journal of electromagnetic Analysis and Applications 2013年第10期5卷 379-387页

作者： Hany M. Zamel Essam el Diwany hadia el hennawy electronics Research Institute (ERI) Microwave Engineering Department Cairo Egypt Faculty of Engineering Ain Shams University Cairo Egypt

In cloaking, a body is hidden from detection by surrounding it by a coating consisting of an unusual anisotropic nonhomogeneous material. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line. The radially-dependent spherical cloaking shell can be approximately discretized into many homogeneous anisotropic layers;each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. In this work, the scattering properties of cloaked dielectric sphere is investigated using a combination of approximate cloaking, where the dielectric sphere is transformed into a small sphere rather than to a point, together with discretizing the cloaking material using pairs of homogeneous isotropic sub-layers. The back-scattering normalized radar cross section, the scattering patterns are studied and the total scattering cross section against the frequency for different number of layers and transformed radius.

关键词： Approximate Cloaking Dielectric Sphere Cloaking by Layered Isotropic Materials

Performance of Analysis Cognitive Radio with Cooperative Sensing under Malicious Attacks over Nakagami Faded Channels

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Wireless Engineering and Technology 2016年第2期7卷 67-74页

作者： Hagar O. Shazly Asmaa Saafan Hesham el Badawy hadia M. el hennawy Faculty of Engineering Ain Shams University Cairo Egypt National Telecommunication Institute (NTI) Cairo Egypt

The different realistic propagation channels are faced frequently the multipath fading environments. The main goal of this system design (cognitive radio network) is to improve the efficiency of spectrum access on a non-interfering basis. This system achieves high utilization for the limited spectrum in order to fulfill needs for all users’ demands which are considered as a problem in wireless communications due to rapidly increasing in wireless applications and service. This system is exposed to attack due to the vulnerabilities existence in this system. So, the main outcome of this paper is to investigate the performance of the cooperative sensing in cognitive radio networks under malicious attacks over different channel impairments, and to illustrate the most suitable individual probability of detection in real faded channel by using Nakagami model. This paper illustrates the effectiveness of the attacks and fading on the performance of spectrum sensing process.

关键词： Cognitive Radio Cooperative Sensing Malicious Attacks Nakagami Faded Channels

Performance Assessment of Coded-Beam High Throughput Satellites

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International Journal of Communications, Network and System Sciences 2017年第8期10卷 218-226页

作者： Eman S. Abass Joseph V. M. Halim hadia M. el-hennawy electronics and Communication Department MTI University Cairo Egypt electronics and Communication Department Ain Shams University Cairo Egypt

High-throughput satellite (HTS) systems usually make use of Multibeam coverage at high frequency bands in order to offer broadband access of large areas. Multibeam coverage increases the available capacity through frequency reuse and spatial separation. However, one of its major drawbacks is inter- spot interference which considered the motivation to propose a new approach using a coding technique to distinguish between beams that will be employed to mitigate this interference without the need of frequency reuse. This approach makes the use of orthogonal codes to identify beams and allow using the total satellite bandwidth per beam. Proposed system double the bandwidth used in each beam and save the usage of antenna polarization resource used in former designs, which may be used as a multiple accessing resource inside the coded beams. The objective of this paper is to provide a comprehensive performance assessment methodology for the proposed approach. Result validation is introduced by comparing the proposed system performance with conventional systems that relay on the DVB standards.

关键词： High-Throughput Satellites Multibeam Satellites Coded Beams Walsh Coding CDMA Satellites

Plasma concentrations of chlorinated persistent organic pollutants and their predictors in the general population of Algiers, Algeria

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Emerging Contaminants 2021年第1期7卷 35-42页

作者： el hadia Mansouri Mohamed Reggabi Toxicology Laboratory Medicine FacultySpecialized Ali Ait Idir HospitalAlgiers16000Algeria

Background:Persistent organic pollutants(POPs)are subject of particular attention and in-depth studies which demonstrate their toxicity towards humans and biotope in *** are therefore addressed by the Stockholm Convention globally with human milk or blood as matrix for effectiveness ***:The objective of this study was to assess plasma concentrations of certain chlorinated POPs in subjects from the urban population in ***:A total number of 207 adult subjects were recruited in Algiers and plasma concentrations of Hexachlorobenzene(HCB),p,p’Dichlorodiphenyl DichloroEthylene(4,40 DDE)and Polychlorinated Biphenyls(PCBs)were determined by gas chromatography with mass spectrometry detection(GC-MS).Results:The nanogram per gram of lipids(ng g^(-1) lipids)geometric means of plasma concentrations of studied compounds were:6.09 for HCB,131.60 for 4,40 DDE,8.61 for PCB153,7.95 for PCB138 and 8.39 for *** 180,PCB 153 and PCB 138 showed a high correlation with each other(r>0.5).4,40 DDE concentrations were significantly higher in women and in subject with low educational level,whereas POPs were higher in older participants(>65 years old).Organochlorine pesticides(OCPs)and PCB153 concentrations were higher in overweight and obese *** was no significant difference between POPs concentrations according to breastfeeding history,smoking status or fish ***:Chlorinated POPs were detected in the blood plasma of adults living in *** concentrations were consistent with those of several studies in the ***,further investigations are needed to assess the exposure profile of subjects living near contaminated sites.

关键词： Organochlorine pesticides Polychlorinated biphenyls POPs Human biomonitoring Stockholm convention

Coastal wetland vegetation features and digital Change Detection Mapping based on remotely sensed imagery:el-Burullus Lake, Egypt

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International Soil and Water Conservation Research 2020年第1期8卷 66-79页

作者： Asmaa Nasser Mohamed Eid C.O.Olatubara T.A.Ewemoje Haitham Farouk Mohamed Talaat el-hennawy Department of Environmental Management The Pan African University for Earth and Life Sciences Including Health and AgricultureUniversity of IbadanIbadanNigeria Department of Computer Science Faculty of Computers and InformationSuez UniversitySuezEgypt Nature Conservation Sector of the Ministry of Environment Egypt

el-Burullus Lake is one of the four Egyptian Ramsar sites that constitute internationally important wetlands as they contain a rich biodiversity and have a large number of water bird *** the valuable resources in el-Burullus Lake and its surrounding area have faced various threats to wetlands over recent *** study was carried out to evaluate the dynamics of land cover change using three change scenes of recent and past satellite data from 1990 to *** study utilized ArcGIS10.7,ERDAS Imagine 14,Landsat TM(1990,1999,and 2010),Landsat OLI-TIRS(2019)to analyze the land-use/land-cover(LULC)of el-Burullus *** Difference Vegetation Index(NDVI)and Normal-ized Difference Water Index(NDWI)were employed to assess the change scenario of the *** indicated that vegetated land has increased significantly with a concomitant shrinkage in the water body and open soil during the study *** 53 km^2(7.0%)of water body and 8.7 km^2(1.3%)of open soil were lost,while vegetation areas expanded to approximately 29.9 km^2(7.4%).Factors that underpin the observed changes in the area are;reclamation projects and fish-farms which are creating the danger of drying up of the southern coastal parts of the lake,as well as spreading of reed beds(mainly:Phragmites australis)that covers about 20%of el-Burullus lake which led to dry up the lake ***,the study suggests the need for urgent attention on conservation of remaining wetland resources for sustainable utilization for the next generation.

关键词： el-burullus natural wetlands LULC NDVI NDWI Remote sensing Vegetation indices

Safety and efficacy of Hansenula-derived PEGylated-interferon alpha-2a and ribavirin combination in chronic hepatitis C Egyptian children

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World Journal of Gastroenterology 2014年第16期20卷 4681-4691页

作者： Suzan el Naghi Tawhida Y Abdel-Ghaffar Hanaa el-Karaksy elham F Abdel-Aty Mona S el-Raziky Aleef A Allam Heba Helmy Hanaa A el-Araby Behairy E Behairy Mohamed A el-Guindi Hatem el-Sebaie Aisha Y Abdel-Ghaffar Nermin A Ehsan Ahmed M el-hennawy Mostafa M Sira Pediatric Department National Hepatology and Tropical Medicine Research Institute11441 CairoEgypt Yassin Abdel Ghaffar Charity Center for Liver Disease and Research 2851 CairoEgypt Pediatric Department Ain Shams University11566 CairoEgypt Department of Pediatrics Cairo University Pediatric Hospital11562 CairoEgypt Pediatric Hepatology Department National Liver InstituteMenofiya UniversityShebin El-koom32511 MenofiyaEgypt Biochemistry Department National Liver Institute32511 MenofiyaEgypt Clinical Pathology Department Ain Shams University11566 CairoEgypt Pathology Department National Liver InstituteMenofiya UniversityShebin El-koom32511 MenofiyaEgypt Pathology Department Cairo UniversityFaculty of MedicineKasr El-Aini11562 CairoEgypt

AIM: To investigate the safety and efficacy of a Hansenula-derived PEGylated (polyethylene glycol) interferon (IFN)-alpha-2a (Reiferon Retard) plus ribavirin customized regimen in treatment-naïve and previously treate... 详细信息

关键词： Children Chronic hepatitis C Hansenula polymorpha PEGylated interferon Response rate Ribavirin Treatment

Colonoscopy in elderly Patients with Hemorrhoidal Disease and Average-Risk for Colorectal Cancer, a Qatari Community Hospital Experience

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Surgical Science 2012年第12期3卷 576-579页

作者： Hany M. el hennawy Ahmed M. Badi Alaa eldin A. Basheer Department of General Surgery Al Khor Hospital Hamad Medical Corporation Doha Qatar Department of Medicine Al Khor Hospital Hamad Medical Corporation Doha Qatar

Introduction: Hemorrhoids are a frequent and familiar concern of patients in the general practice and surgery settings. Colonoscopy is both diagnostic and therapeutic. In Qatar, There are little data available about coincidental pathology in elderly patients with hemorrhoids. Objective: To assess the outcome of colonoscopy in management patients with hemorrhoidal disease and average-risk for colorectal cancer and its clinical significance. Method: A retrospective study of 200 patients with hemorrhoids with average risk colorectal cancer (anal bleeding and anal symptoms) and subjected to colonoscopic examination at Al Khor hospital’s endoscopy unit during the period from May 2005 till August 2012. Patients below 50 years and high risk patients for colorectal cancer;with the following alarm signs: Positive personal history of colorectal neoplasms or Inflammatory Bowel Disease (IBD), positive first degree family history of colorectal neoplasms, history of altered bowel habits, recent significant weight loss, presence of iron deficiency anemia, and history of previous colonoscopy were excluded. All significant endoscopic co-findings (diverticuli, polyps, cancer, angiodysplasia and varices, or colitis) were recorded. Results: There were 200 patients;134 male, 66 female;Mean patient age was 56.3 years (range, 50 to 82 years), who met the eligibility criteria. 200 colonoscopies were performed. Evaluation of these patients revealed Polyps in 16 patients (13 benign and 3 malignant), seven malignant lesions(one annular lesion and 6 fungating masses), Ulcerative colitis in 5 patients, no crohn’s disease, diverticular disease in 4 patients, no Vascular malformations, bleeding piles in 3 patients controlled by injection, and 65.5% of patients were free from any additional pathology. Colonoscopy changed the treatment plan in 58 patients (29%). No complications were encountered. Conclusion: Coincidental abnormalities in colon and rectum in elderly patients with hemorrhoids are com

关键词： Colonoscopy elderly Hemorrhoidal Disease Colorectal Cancer

Accuracy of Fine Needle Aspiration Cytology of Solitary Thyroid Nodules in Tertiary versus Community Hospital

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Surgical Science 2013年第11期4卷 494-499页

作者： H. M. el hennawy H. O. Abu Zaid Imaad Bin Mujeeb Eihab A. el Kahlout el S. M. Bedair Medicine Department Al Khor Hospital Hamad Medical Corporation Doha Qatar Pathology Department Hamad General Hospital Hamad Medical Corporation Doha Qatar Radiology Department Al Khor Hospital Hamad Medical Corporation Doha Qatar Surgery Department Al Khor Hospital Hamad Medical Corporation Doha Qatar Trauma Surgery Department Hamad General Hospital Hamad Medical Corporation Doha Qatar

Background: Fine needle aspiration cytology (FNAC) is considered as the gold standard diagnostic test for the diagnosis of solitary thyroidnodules (STN). Aim: To compare the accuracy of FNAC in diagnosis of thyroid nodules in Al Khor community hospital versus that of tertiary hospital (Hamad General Hospital) in Qatar. Methods: Retrospective, descriptive and comparative study of 320 patients of any age group and both sexes who have thyroid nodules and are subjected to surgical treatment [160 patients from Al Khor community hospital (group A) and 160 patients from Hamad General Hospital (group B)] during the period from May 2005 to Dec 2012. Each group was subdivided into free hand FNAC (done by physicians) and ultrasonography guided FNAC. All samples were prepared in the same histopathology laboratory and interpreted by the same histopathology team. Results: Free hand FNAC in group A and group B achieved a sensitivity of (10% vs. 50%), specificity of 93% in both groups, positive predictive value of (25% vs. 17%), negative predictive value of (82% vs. 98%), and a total accuracy of (82% vs. 94%) respectively, while US guided FNAC in group A and group B achieved a sensitivity of (10% vs. 86%), specificity of (98% vs. 94%), positive predictive value of (50% vs. 60%), negative predictive value of (86% vs. 98%), and a total accuracy of (85% vs. 97%) respectively. Conclusion: The overall accuracy of FNAC of STN in tertiary hospital was better than community hospital. More training is required for community hospital staff.

关键词： Needle Aspiration Solitary Thyroid Nodules Accuracy

Exocrine drainage in vascularized pancreas transplantation in the new millennium

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World Journal of Transplantation 2016年第2期6卷 255-271页

作者： Hany el-hennawy Robert J Stratta Fowler Smith Depart-ment of Surgery Wake Forest School of Medicine

The history of vascularized pancreas transplantation largely parallels developments in immunosuppression and technical refinements in transplant surgery. From the late-1980 s to 1995, most pancreas transplants were whole organ pancreatic grafts with insulin delivery to the iliac vein and diversion of the pancreatic ductal secretions to the urinary bladder(systemic-bladder technique). The advent of bladder drainage revolutionized the safety and improved the success of pancreas transplantation. However, starting in 1995, a seismic change occurred from bladder to bowel exocrine drainage coincident with improvements in immunosuppression, preservation techniques, diagnostic monitoring, general medical care, and the success and frequency of enteric conversion. In the new millennium, pancreas transplants are performed predominantly as pancreatico-duodenal grafts with enteric diversion of the pancreatic ductal secretions coupled with iliac vein provision of insulin(systemic-enteric technique) although the systemic-bladder technique endures as a preferred alternative in selected cases. In the early 1990 s, a novel technique of venous drainage into the superior mesenteric vein combined with bowel exocrine diversion(portal-enteric technique) was designed and subsequently refined over the next ≥ 20 years to recreate the natural physiology of the pancreas with firstpass hepatic processing of insulin. Enteric drainage usually refers to jejunal or ileal diversion of the exocrine secretions either with a primary enteric anastomosis or with an additional Roux limb. The portal-enteric technique has spawned a number of newer and revisited techniques of enteric exocrine drainage including duodenal or gastric diversion. Reports in the literature suggest no differences in pancreas transplant outcomes irrespective of type of either venous or exocrine diversion. The purpose of this review is to examine theliterature on exocrine drainage in the new millennium(the purported "enteric drainage

关键词： Pancreas transplantation Portal-enteric drainage Simultaneous pancreas-kidney transplant Systemic-bladder drainage Enteric conversion Solitary pancreas transplant Systemic-enteric drainage