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The 19th International Workshop on Electromagnetic Induction in the Earth

作者： usama massoud mohamed Abdalla Gad El-Qady Ferna ndo Santos National Research Institute of Astronomy and Geophysics(NRIAG) 11722HelwanCairoEgypt Center of Geophysics Lisbon University(CGUL)1749-016LisbonPortugal

In the past few years,construction extended extraordinarily to the southeast of Cairo,Egypt,where limestone caves *** existence of caves and sinkholes represents a hazard for such new urban *** state is planning to construct a new housing community ***,it is important to map and delineate these natural voids and cavities before construction. Recently,cavity imaging by means of geophysical surveys became more *** this paper,DC resistivity survey had been applied at Al-Amal city,east of Qattamiya,Cairo to image the shallow subsurface and possibly karstic features and ***-two vertical electrical soundings were measured using the common Schlumberger array of electrode configuration with a maximum AB/2 spacing of 200 m.A 3-D inversion scheme was applied to the measured *** results of VES data inversion subdivided the shallow subsurface section in the study area into three main geoelectrical *** uppermost unit composed of sand,gravel and fossiliferous limestone with high resistivity values and small *** second unit is composed of sandy clay and clay with low resistivity *** third unit is considered to be the bed rock,where it consists of consolidated sand,limestone and marl with relatively high resistivity values. The results elucidated many geoelectrical variations which could be interpreted as litho-facies *** was also revealed that,the area is dissected by some normal faults affecting the second and third geoelectrical *** addition, numerous cavernous structures could be elucidated at shallow to intermediate *** features are too important to be taken into account during the housing development plans.

关键词： VES data 3-D inversion cave Egypt

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Clinicopathological features and treatment outcomes of brain stem gliomas in Saudi population

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World Journal of Clinical Oncology 2014年第5期5卷 1060-1067页

作者： Yasser Bayoumi Abdulrahman J Sabbagh Reham mohamed usama m El Shokhaiby Ahmed marzouk maklad mutahir A Tunio Ali Abdullah O Balbaid Consultant Radiation Oncology Comprehensive Cancer Center King Fahad Medical City Riyadh-59046 Saudi Arabia Radiation Oncology NCI Cairo University Cairo 11435 Egypt Neurosurgery King Fahad medical City Riyadh-59046 Saudi Arabia Radiation Oncology NCI Cairo University Cairo 11435 Egypt Clinical Oncology Sohag University Sohag 11432 Egypt Radiation Oncology Comprehensive Cancer Center King Fahad Medical City Riyadh-59046 Saudi Arabia

AIm: To analyze experiences to identify treatment outcomes and prognostic factors in a Saudi ***: medical records of patients with brainstem gliomas treated from July 2001 to December 2012 were reviewed to identify treatment outcomes of surgery, radiation therapy and chemotherapy and associated prognostic factors in a Saudi ***: We analyzed 49 brain stem glioma(BSG) patients from July 2001 to December 2012; 31 of them were males(63.3%) with a median age of 12.6 years(range: 8-64 mo). Twenty-two patients(44.9%) had diffuse intrinsic pontine gliomas(DIPG) and 15(30.6%) presented with focal/tectal BSG. Histopathology was available in 30 patients(61.2%). median survival time for the whole cohort was 1.5 years. One and two year OS rates were 51.1% and 41.9% respectively. Two year OS rates for focal/tectal, dorsally exophytic, cervicomedullary and DIPG tumors were 60%, 33.3%, 33.3% and 13.6% respectively(P 18 years) P = 0.01, KPS mptoms(maximal resection) P = 0.002, and concurrent chemotherapy with radiation therapy in DIPG(better if given) P = ***: BSG, especially the DIPG subgroup, had a dismal prognosis, needing more aggressive neurosurgical, radiation and chemotherapy techniques, while focal and tectal tumors were found to have a better prognosis.

关键词： Brain stem glioma Children Adults Saudi Arabia Treatment outcomes

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Wi-Fi能量捕集柔性RF天线的设计与3D打印研究

Wi-Fi能量捕集柔性RF天线的设计与3D打印研究

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作者：穆罕默德乌萨马拉扎（muhammad usama Raza）常州大学

学位级别：硕士

射频(RF)能量收集作为一种产生微量电能来为无线连接的设备供电有着光明的未来。小型电子设备的电力存储是电路中的主要问题。最紧迫的问题是如何提供可靠的电源,使这些设备能够自主运行。传统设备主要依赖电池系统,但随着时间的推移,... 详细信息

射频(RF)能量收集作为一种产生微量电能来为无线连接的设备供电有着光明的未来。小型电子设备的电力存储是电路中的主要问题。最紧迫的问题是如何提供可靠的电源,使这些设备能够自主运行。传统设备主要依赖电池系统,但随着时间的推移,电池会耗尽存储的能量。随着电池的大规模更换,系统的成本肯定会上升。为了避免维护成本问题,环境能量获取技术开始受到研究界的相当关注。但是,在环境中,他们拥有不同类型的设备。单独高效供电的弊端难以避免。为了克服这一限制,本研究提出了一种捕集Wi-Fi能量的柔性RF天线,设计了能量采集系统,可以在自然环境中采集射频能量。本工作首先设计并制作了能量采集系统的能量采集器。探讨了天线设计的技术和关键技术,包括如何计算单元天线、阵列和馈电网络的尺寸,研制工作频率为2.45GHz的矩形贴片微带天线。通过微调尺寸参数和馈电点位置,该天线在2.45GHz处获得了较高的传输性能和矩形极化特性。物理数据与加工测试后的模拟数据基本一致,调查两者差异较小的原因。使用天线设计软件COmSOL进行了天线仿真,考虑环境中广泛分布的无线Wi-Fi信号、仿真和优化矩形贴片天线,包括分别工作在2.45GHz的2x2和单位矩形贴片天线。3D打印了贴片天线模型,将Ga-In-Sn液态金属注入3D打印模型的孔,3D打印的孔道,制造出柔性3D打印天线的导电层。对于设计天线的这种灵活性和性能,我们使用3D打印技术。与任何其他制造技术相比,3D打印技术将复杂的贴片天线紧凑化并且具有低成本价值。最后,设计了在2.45GHz至3.6GHz频率范围内的整流器升压电路,用于捕获Wi-Fi信号的射频能量应用。柔性模拟天线连接整流电路和能量采集器,将Wi-Fi信号能量转换为稳定的直流能量。我们在0m、1m、2m、3m和Wi-Fi路由器的关闭状态等不同距离收集能量。Wi-Fi用作发射天线,测量放置不同距离时的充电容量值。从实验中我们可以计算电荷密度随时间的变化,了解Wi-Fi发射天线对射频能量收集电路的影响。然而,随着我们增加作为发射器天线的Wi-Fi和射频能量收集器电路之间的距离,接收器天线的电荷容量值会降低,并且需要更多的时间来为电路充电。我们以Wi-Fi路由器作为发射天线计算从0m到3m的范围内的充电容量值。

关键词：矩形贴片天线能量捕集射频无线连网 3D打印

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A multi-proxy reconstruction of spatial and temporal variations in Asian summer temperatures over the last millennium

A multi-proxy reconstruction of spatial and temporal variati...

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中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Feng Shi Quansheng Ge Bao Yang Jianping Li Fengmei Yang Fredrik Charpentier Ljungqvist Olga Solomina Takeshi Nakatsuka Ninglian Wang Sen Zhao Chenxi Xu Keyan Fang masaki Sano Guoqiang Chu Zexin Fan Narayan P.Gaire muhammad usama Zafar Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University Joint Center for Global Change Studies China meteorological Administration Training Centre Department of History Stockholm University Bolin Centre for Climate Research Stockholm University Institute of Geography Russian Academy of Sciences Tomsk State University Central Department of Environmental Science Tribhuvan University

To investigate climate variability in Asia during the last millennium, the spatial and temporal evolution of summer(June–July–August;JJA) temperature in eastern and south-central Asia is reconstructed using multi-proxy records and the regularized expectation maximization(RegE m) algorithm with truncated total least squares(TTLS), under a point-by-point regression(PPR) framework. The temperature index reconstructions show that the late 20 th century was thewarmest period in Asia over the past millennium. The temperature field reconstructions illustrate that temperatures in central, eastern, and southern China during the 11 th and 13 th centuries, and in western Asia during the 12 th century, were significantly higher than those in other regions, and comparable to levels in the 20 th century. Except for the most recent warming, all identified warm events showed distinct regional expressions and none were uniform over the entire reconstruction area. The main finding of the study is that spatial temperature patterns have, on centennial timescales, varied greatly over the last millennium. moreover, seven climate model simulations, from the Coupled model Intercomparison Project Phase 5(CmIP5), over the same region of Asia, are all consistent with the temperature index reconstruction at the 99 % confidence level. Only spatial temperature patterns extracted as the first empirical orthogonal function(EOF) from the GISS-E2-R and mPI-ESm-P model simulations are significant and consistent with the temperature field reconstruction over the past millennium in Asia at the 90 % confidence level. This indicates that both the reconstruction and the simulations depict the temporal climate variability well over the past millennium. However, the spatial simulation or reconstruction capability of climate variability over the past millennium could be still limited. For reconstruction, some grid points do not pass validation tests and reveal the need for more proxies with high temporal res

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