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Petrologic and geochemical characterization and mineralization of the metavolcanic rocks of the Heib Formation,Kid Metamorphic Complex,Sinai,Egypt

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Geoscience Frontiers 2011年第3期2卷 385-402页

作者： Ibrahim H.Khalifa Mohammed Z.El-Bialy doa.a M.Hassan Geology Department Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Geology Department Faculty of SciencePort Said UniversityPort SaidEgypt

Metavolcanic rocks hosting base metal sulphide mineralization, and belonging to the Kid Metamorphic Complex, are exposed in the Samra-Tarr area, Southern Sinai. The rocks consist of slightly metamorphosed varicolored porphyritic lavas of rhyolite-to-andesite composition, and their equivalent pyroclastics. Geochemically, these metavolcanics are classified as high-K calc-alkaline, metaluminous andesites, trachyandesites, dacites, and rhyolites. The geochemical characteristics of these metavolcanics strongly point to their derivation from continental crust in an active continental margin. The sulphide mineralization in these metavolcanics occurs in two major ore zones, and is represented by four distinct styles of mineralization. The mineralization occurs either as low-grade disseminations or as small massive pockets. The associated hydrothermal alterations include carbonatization, silicification, sericitization and argillic alterations. The base metal sulphide mineralization is epigenetic and was formed by hvdrothermal solutions associated with subduction-related volcanic activity.

关键词： Calc-alkaline Sulphides Mineralization Metavolcanic rocks Sinai

The Effectiveness of Video Distraction on Children Preoperative Anxiety: An Integrative Literature Review

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Open Journal of Nursing 2018年第3期8卷 171-187页

作者： doa.a Dwairej Hala Obeidat Inaam Khalaf School of Nursing The University of Jordan Amman Jordan Princess Muna College of Nursing Mutah University Amman Jordan

Background: Children who undergo a day case surgery experience high levels of preoperative anxiety. Preoperative anxiety interferes with anesthesia induction compliance and is associated with many short and long term postoperative complications. Recently, video distraction intervention has been evaluated for its anxiolytic effects in preoperative children. Aim: The aim of this integrative review was to demonstrate the varying methodological approaches utilized to evaluate the effectiveness of a video distraction intervention in reducing preoperative anxiety in children undergoing day case surgery. Methods: A total of 8 articles, meeting the inclusion criteria, were evaluated and included. Findings: The eight studies investigating the effect of video distraction on children preoperative anxiety concluded that video distraction was significant in controlling children preoperative anxiety. Four of the eight studies (50%), investigated video distraction effectiveness against pharmacological comparisons and demonstrated superior or equal anxiolytic effect of video distraction on different points along the surgical continuum. Three of the eight studies compared video distraction against parental presences and video distraction showed superior anxiolytic effect. Three of the eight studies evaluated the effect of video distraction on anesthesia induction compliance and emergence delirium. A significant effect on anesthesia induction was demonstrated while non-significant effect on emergence delirium was documented. Conclusion: Video distraction is a safe, time and cost effective non pharmacological anxiolytic intervention. It can be provided by nurses to control children high level of anxiety before surgery and during anesthesia induction.

关键词： Video Distraction Preoperative Anxiety Children Anesthesia Induction Compliance Emergence Delirium

Applicability and efficacy of a model for prevention of perinatal transmission of hepatitis B virus infection:Single center study in Egypt

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World Journal of Gastroenterology 2014年第45期20卷 17075-17083页

作者： Hanaa M El-Karaksy Lamiaa M Mohsen doa.a A Saleh Mona S Hamdy Noha A Yassin Mohamed farouk Mohamed E Salit Mortada H El-Shabrawi Department of Pediatrics Kasr Al-Ainy School of Medicine Cairo University Department of Community Medicine Kasr AlAiny School of Medicine Cairo University Department of Clinical and Chemical Pathology Kasr Al-Ainy School of Medicine Cairo University Department of Obstetrics and Gynecology Kasr Al-Ainy School of Medicine Cairo University

AIM: To identify possible maternal risk factors for hepatitis B virus (HBV) acquisition and assess the efficacy of immunoprophylaxis given to infants born to hepatitis B virus surface antigen (HBsAg) positive mothers.

关键词： Egypt Hepatitis B virus Hepatitis B virus surface antigen positive mothers Immunoprophylaxis Perinatal transmission

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基于虚拟阵列空间平滑的相干信号doa.计

电子学报 2010年第4期38卷 929-933页

作者：张聪胡谋法卢焕章西南电子电信技术研究所四川成都610041 国防科学技术大学电子科学与工程学院湖南长沙410073

针对相干共轭循环平稳信号的doa.计问题,提出了一种基于虚拟阵列前后向空间平滑的方法.该方法利用特定阵元输出间共轭循环相关函数的多时延采样,构造出与真实线阵阵元具有一一对应关系的虚拟阵列,并将空间平滑技术应用于该虚拟阵列实... 详细信息

针对相干共轭循环平稳信号的doa.计问题,提出了一种基于虚拟阵列前后向空间平滑的方法.该方法利用特定阵元输出间共轭循环相关函数的多时延采样,构造出与真实线阵阵元具有一一对应关系的虚拟阵列,并将空间平滑技术应用于该虚拟阵列实现了相干信号doa.计.理论分析和仿真结果均表明,与FBSS-CCMUSIC算法和CCHAM算法相比,本文方法避免了最优时延选择问题,并获得了更高的doa.计精度,同时,对信号不同入射方向也具有较好的稳健性.此外,该方法也可推广用于具有循环平稳特性的信号.

关键词：阵列信号处理波达方向循环平稳相干空间平滑

Conotruncal heart malformations in Egypt: An epidemiological study

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Open Journal of Epidemiology 2013年第4期3卷 169-176页

作者： doa.a A. Saleh Sameera Ezzat Hala Hamza Mohamed Abdel-Hamid Karen S. Kuehl Christopher A. Loffredo Cairo University Cairo Egypt Children’s National Medical Center Washington DC USA Georgetown University Washington DC USA Menoufiya University Shibin El Kom Egypt Minia University Minia Egypt

Conotruncal malformations of the heart are a major category of birth defects. No previous epidemiological studies on these malformations have been carried out in Egypt;therefore our study aimed to describe associations with maternal and infant factors in order to identify possible risk factors. Cases (N = 255) were children up to two years of age whose heart malformations were confirmed by echocardiography;they were enrolled at the Cardiology Department of the Pediatric Hospital of Cairo University. Controls (N = 155) were free of congenital heart malformations, matched to the cases by age, and recruited from outpatients of the same hospital. Mothers of cases (97%) and controls (89%) provided consent to participate in an interview about their medical, familial, and occupational histories. Odds ratios (OR) and exact 95% confidence intervals (CI) assessed the magnitude and statistical significance of case-control differences. Cases were divided into two groups based on the presence of d-transposition of the great arteries (TGA): there were 139 with TGA and 116 with normally-related great arteries (NGA). Maternal diabetes prevalence was elevated in both the TGA (OR = 3.4) and NGA (OR = 5.5) subgroups. Several agricultural factors were associated with increased risk: raising animals (for TGA: OR = 2.4, 95% CI 1.2-4.6), raising poultry (for NGA: OR = 1.8, 95% CI 1.1-3.2), and using chemical rodenticides (for all conotruncal cases: OR = 3.2, 95% CI 1.1-13.2). These results are consistent with previous studies of associations of maternal diabetes and pesticide exposure with conotruncal malformations. Further research is warranted to explore such associations and determine avenues for prevention.

关键词： Congenital Heart Disease Cardiovascular Malformations Conotruncal Malformations Epidemiology Environmental factors Diabetes

基于虚拟基线变换和RBFNN的宽频段doa.计

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宇航学报 2012年第2期33卷 210-216页

作者：李鹏飞张旻钟子发合肥电子工程学院合肥230037 安徽省电子制约技术重点实验室合肥230037

提出利用虚拟基线变换的方法解决了频率高端的相位模糊,克服由于相位模糊性造成的方向特征的多值模糊问题,从而简化了从方向特征到波达方向的映射关系。提取无模糊的方向特征,训练RBF神经,进行宽频段波达方向估计。理论分析和试验表明,... 详细信息

提出利用虚拟基线变换的方法解决了频率高端的相位模糊,克服由于相位模糊性造成的方向特征的多值模糊问题,从而简化了从方向特征到波达方向的映射关系。提取无模糊的方向特征,训练RBF神经,进行宽频段波达方向估计。理论分析和试验表明,该解模糊方法计算量小,能有效消除圆阵列的相位模糊,适用阵元数大于等于5的任意均匀圆阵列天线(6元除外);利用解模糊后的特征建立的doa.计模型结构简单,性能大大优于直接建模和相关干涉仪法,具有优越的性能和工程实用性。

关键词：解模糊虚拟基线宽频段神经网络波达方向

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基于空间角稀疏表示的二维doa.计

电子与信息学报 2011年第10期33卷 2402-2406页

作者：李鹏飞张旻钟子发合肥电子工程学院309研究室合肥230037 安徽省电子制约技术重点实验室合肥230037

论文提出一种基于空间角稀疏表示的2维doa.计方法,解决了2维doa.计中冗余字典构造的难题。构建的空间角包含了方位角和俯仰角的信息,利用其构造冗余字典可以将方位角和俯仰角的组合从2维空间映射到1维空间,极大地降低了字典的长度和... 详细信息

论文提出一种基于空间角稀疏表示的2维doa.计方法,解决了2维doa.计中冗余字典构造的难题。构建的空间角包含了方位角和俯仰角的信息,利用其构造冗余字典可以将方位角和俯仰角的组合从2维空间映射到1维空间,极大地降低了字典的长度和求解的复杂度;同时将算法推广到频域,扩展了其应用范围。与传统的高分辨算法相比,该方法对信噪比和快拍数要求不高、无需特征值分解和多维搜索过程。理论分析和仿真实验,验证了该方法对2维相干信号和非相干信号都具有较高的估计精度和较好的分辨力,在不同信噪比下性能优于MUSIC算法。

关键词：信号处理波达方向 2 维角稀疏表示空间角

基于PWLCM和秃鹰俯冲机制改进的野狗优化算法

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计算机与现代化 2024年第1期 109-116页

作者：欧基发蔡茂国洪广杰詹楷杰深圳大学电子与信息工程学院广东深圳518060

针对野狗优化算法(Dingo Optimization Algorithm,doa.收敛速度偏慢和寻优精度较低等问题,提出一种基于PWLCM和秃鹰机制改进的野狗优化算法(Improved Dingo Optimization Algorithm,Idoa.。首先,使用具有遍历性的分段线性混沌映射(Piece... 详细信息

针对野狗优化算法(Dingo Optimization Algorithm,doa.收敛速度偏慢和寻优精度较低等问题,提出一种基于PWLCM和秃鹰机制改进的野狗优化算法(Improved Dingo Optimization Algorithm,Idoa.。首先,使用具有遍历性的分段线性混沌映射(Piecewise Linear Chaotic Map,PWLCM)初始化野狗种群,有效增加野狗种群多样性。其次,在迫害策略中引入秃鹰俯冲机制,加快野狗捕获猎物的速度,加强算法探索局部的能力。最后,在食腐策略引入螺旋搜索因子,增强算法的局部寻优能力,提升算法的寻优速度和求解精度。仿真实验数据、消融实验以及Wilcoxon秩和检验均表明,与其他对比算法相比,提出的Idoa.所有测试函数上有着更佳的寻优速度以及寻优精度;与其他改进的野狗优化算法相比,所提出的Idoa.现出更好的整体性能。

关键词：野狗优化算法分段线性混沌映射秃鹰俯冲机制螺旋搜索因子

A New Method for doa.Estimation Based on RBF Neural Network

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A New Method for DOA Estimation Based on RBF Neural Network