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environmental che.ical study on the marsh of Fatimid cemetery at Aswan City, egypt

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Journal of environmental Sciences 2002年第4期14卷 464-473页

作者： M.e.Soltan Chemistry Department Faculty of Science

environmental che.ical study were carried out on the Fatimid cemetery marsh at Aswan City(24°1'N and 32°9'e), egypt. Marsh contents(warter, soil, sediment, metal and nonmetal bearing salts, and emergent weed) were analysed to known the source of marsh water, speciation of the different elements between the marsh contents, and the toleration of emergent weed (Phargmites australies) for different metals and their bioaccumulation coefficients. Thus, metals(ca, Mg, Na, K, Ni, Fe, Mn, Cu, Zn, Cd and Pb) and nonmetals(CO 2- 3, HCO - 3, Cl -, SO 2- 4, PO 3- 4, NO - 3, SiO 2, organic matter and pH value) were determined in the samples. According to the che.ical analysis, and applying the base exchange equation(water type) and calculate the hydroche.ical parameters for marsh water samples, we can indicate that the marsh water is ground water with Na SO 4 type and deep meteoric genesis. Topsoil of marsh dry land characterized by caCl as dominant salt,while NaCl is a dominant salt in subsoil. The elevated pH values of marsh contents minimized the metal solubilities in different samples. Phragmites australies showed a strong ability to accumulate Mn and Fe in the aerial part in opposite to Co, Ni and Cd.

关键词： marsh water soil sediment emergent weed egypt

Seven possible states of geospatial data with respect to map projection and definition: a novel pedagogical device for GIS education

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Geo-Spatial Information Science 2018年第4期21卷 288-293页

作者： Steven e.Greco Department of Human ecology University of CaliforniaDavisCAUSA

Conceptually,the theory and implementation of“map projection”in geographic information system(GIS)technology is difficult to comprehend for most introductory students and novice *** this difficulty is the concept of a“map projection file”that defines map projection parameters of geo-spatial *** problem of the“missing projection file”appears ubiquitous for all users,especially in practice where data is widely *** common problem is inadvertent misapplication of the“Define Projection”tool that can result in a GIS dataset with an incorrectly defined map projection *** education should provide more guidance in differentiating the concepts of map projection versus projection files by increasing understanding and minimizing common errors.A novel pedagogical device is introduced in this paper:the seven possible states of GIS data with respect to map projection and *** seven possible states are:(1)a projected coordinate system(PCS)that is correctly defined,(2)a PCS that is incorrectly defined,(3)a PCS that is undefined,(4)a geographic coordinate system(GCS)that is correctly defined,(5)a GCS that is incorrectly defined,(6)a GCS that is undefined,and(7)a *** created automated troubleshooting tools to determine a missing map projection file are discussed.

关键词： GIS education map projection error map projection file define projection

Highly compliant planar Hall effect sensor with sub 200 nT sensitivity

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npj Flexible electronics 2019年第1期3卷 25-30页

作者： Pablo Nicolás Granell Guoliang Wang Gilbert Santiago cañon Bermudez Tobias Kosub Federico Golmar Laura Steren Jürgen Fassbender Denys Makarov Helmholtz-Zentrum Dresden-Rossendorf e.V. Institute of Ion Beam Physics and Materials ResearchBautzner Landstrasse 40001328 DresdenGermany Instituto Nacional de Tecnología Industrial(INTI) Centro de Micro-y Nanoelectrónica del Bicentenario(CMNB)Av.Gral Paz 5445B1650KNA San MartínBuenos AiresArgentina escuela de Ciencia y Tecnología UNSAMCampus MigueleteB1650KNA San MartínBuenos AiresArgentina Consejo Nacional de Investigaciones Científicas y Técnicas C1425FQB Ciudad Autónoma de Buenos AiresArgentina Instituto de Nanociencia y Nanotecnología B1650KNA San MartínBuenos AiresArgentina Dpto.Materia Condensada Centro Atómico ConstituyentesB1650 San MartínBuenos AiresArgentina

Being a facet of flexible electronics,mechanically reshapeable magnetic field sensorics enable novel device ideas for soft robotics,interactive devices for virtual-and augmented reality and point of care *** applications demand mechanically compliant yet robust sensor devices revealing high sensitivity to small magnetic *** push the detection limit of highly compliant and linear magnetic field sensors to be in the sub-µT range,we explore a new fundamental concept for magnetic field sensing,namely the planar Hall effect in magnetic thin *** their remarkable bendability down to 1 mm,these compliant planar Hall effect sensors allow for an efficient detection of magnetic fields as small as 200 nT with a limit of detection of 20 *** demonstrate the application potential of these devices as a direction(angle)as well as proximity(distance)sensors of tiny magnetic fields emanating from magne.ically functionalized *** their intrinsic linearity and simplicity of fabrication,these compliant planar Hall effect sensors have the potential to become a standard solution for low field applications of shapeable magnetoelectronics in point of care applications and on-skin interactive electronics.

关键词： interactive planar limit

Polarization behavior of elastic scattering from a silicon microsphere coupled to an optical fiber

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Photonics Research 2014年第2期2卷 45-50页

作者： Mohammed Sharif Murib emre Yüce Oğuzhan Gürlü Ali Serpengüzel KoçUniversity Microphotonics Research LaboratoryDepartment of PhysicsRumelifeneri YoluSarıyerIstanbul 34450Turkey Istanbul Technical University Faculty of Sciences and LettersDepartment of PhysicsMaslakSarıyerIstanbul 34469Turkey

The polarization behavior of elastic scattering at 1473 nm is analyzed from a silicon microsphere on an optical fiber *** 0.27 nm angular mode spacing of the resonances correlates well with the optical size of the silicon *** spectral linewidths of the resonances are on the order of 10^(−3) nm,which corresponds to quality factors on the order of *** transverse magne.ically polarized elastic scattering signal has higher resonance to modulation depth and background ratio than the transverse electrically polarized elastic scattering signal and is suitable for high-resolution optical filtering applications such as optical monitoring and sensing.

关键词： transverse behavior polarized

基于动态功率阈值降低PAPR的部分传输序列算法

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系统工程与电子技术 2017年第7期39卷 1620-1624页

作者：季策郭伟张超东北大学计算机科学与工程学院辽宁沈阳110169

为了改善正交频分复用(orthogonal frequency division multiplexing,OFDM)系统的峰均功率比(peak-to-average power ratio,PAPR)性能,提出了一种基于动态功率阈值的低复杂度部分传输序列(partial transmit sequences,PTS)方法。在新的PTS方法中,引入了基于功率的判别函数,并给出了一种基于功率合理选择阈值的方法。在选取最小的PAPR值进行传输时,只对Pn大于等于阈值的样本信号进行峰值功率的计算。与传统的PTS算法相比,本文提出的算法在保证PAPR性能和误码率的情况下,能够更有效地降低计算复杂度。

关键词：正交频分复用峰均功率比部分传输序列阈值

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改进的独立分量分析算法

东北大学学报（自然科学版） 2010年第8期31卷 1086-1088,1097页

作者：季策于洋于鹏东北大学信息科学与工程学院辽宁沈阳110004

对独立分量分析算法的基本理论和Fastica算法进行了简要介绍.传统的Fastica算法只具有二阶的收敛速度,为了提高独立分量分析算法的收敛速度,减少迭代次数和运行时间,提出了一种改进的独立分量分析算法——五阶收敛的牛顿迭代法.对牛顿... 详细信息

对独立分量分析算法的基本理论和Fastica算法进行了简要介绍.传统的Fastica算法只具有二阶的收敛速度,为了提高独立分量分析算法的收敛速度,减少迭代次数和运行时间,提出了一种改进的独立分量分析算法——五阶收敛的牛顿迭代法.对牛顿迭代算法加以修正,使改进的独立分量分析算法具有五阶的收敛速度.图像信号分离仿真实验表明,改进算法与传统的Fastica算法在分离效果相当的情况下,明显减少了传统的Fastica算法的迭代次数和运行时间,提高了收敛速度和运行效率.

关键词：独立分量分析定点算法牛顿迭代法负熵最速下降法

Role of erbB family receptor tyrosine kinases in intrahepatic cholangiocarcinoma

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World Journal of Gastroenterology 2008年第46期14卷 7033-7058页

作者： Alphonse e Sirica Division of cellular and Molecular Pathogenesis Department of PathologyVirginia Commonwealth University School of Medicine

Aberrant expression and signaling of epidermal growth factor receptor (erbB) family receptor tyrosine kinases, most notably that of erbB2 and erbB1, have been implicated in the molecular pathogenesis of intrahepatic cholangiocarcinoma. Constitutive overexpression of erbB2 and/or erbB1 in malignant cholangiocytes has raised interest in the possibility that agents which selectively target these receptors could potentially be effective in cholangiocarcinoma therapy. However, current experience with such erbB-directed therapies have at best produced only modest responses in patients with biliary tract cancers. This review provides a comprehensive and critical analysis of both preclinical and clinical studies aimed at assessing the role of altered erbB2 and/or erbB1 expression, genetic modifications, and dysregulated signaling on cholangiocarcinoma development and progression. Specific limitations in experimental approaches that have been used to assess human cholangiocarcinoma specimens for erbB2 and/or erbB1 overexpression and gene amplification are discussed. In addition, current rodent models of intrahepatic cholangiocarcinogenesis associated with constitutive erbB2 overexpression are reviewed. Select interactive relationships between erbB2 or erbB1 with other relevant molecular signaling pathways associated with intrahepatic cholangiocarcinoma development and progression are also detailed, including those linking erbB receptors to bile acid, cyclooxygenase-2,interleukin-6/gp130, transmembrane mucins, hepatocyte growth factor/Met, and vascular endothelial growth factor signaling. Lastly, various factors that can limit therapeutic efficacy of erbB-targeted agents against cholangiocarcinoma are considered.

关键词： Cholangiocarcinoma erbB activation Bile acids Cyclooxygenase-2 erbB targeted therapies

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激光测量仪信号的形成

中国检验检测 1989年第3期 18-19页

作者： e.B.Aлeкceнкo 李绍贵

在许多工业部门广泛地应用直线量和角度量的非接触精密测量。图1示出了激光测量仪的综合图。激光器和聚焦系统保证按具体要求产生光束来照

关键词：激光测量仪双级放大器光电二极管通频带电子线路光栅

Field measurement of strain response for typical asphalt pavement

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Journal of central South University 2021年第2期28卷 618-632页

作者： PAN Qin-xue ZHeNG ce-ce Lü Song-tao QIAN Guo-ping ZHANG Jun-hui WeN Pi-hua MILKOS Borges cabrera ZHOU Huai-de Key Laboratory of Road Structure and Material of Ministry of Transport(Changsha) School of Traffic and Transportation EngineeringChangsha University of Science&TechnologyChangsha 410114China School of engineering and Materials Science Queen Mary University of LondonLondon E14NSUK

In order to reveal the changing law of the mechanical response of asphalt pavements under the action of vehicle load and provide references for the design of durable pavements,three typical asphalt pavement structures with flexible base(S1),combined base(S2),and semi-rigid base(S3)were selected to perform field strain tests under static and dynamic load using the fiber Bragg grating optical sensing *** changing characteristics of the strain field along the horizontal and depth directions of pavements were *** results indicate that the most unfavorable asphalt pavement layers were the upper-middle surface layer and the lower base *** addition,the most unfavorable loading positions on the surface layer and the base layer were the center of wheel load and the gap center between two wheels,*** most unfavorable layer of the surface layers gradually moved from the lower layer to the upper layer with the increase of base layer *** power function relationships between structural layer strain and vehicle speed were *** semi-rigid base asphalt pavement was the most durable pavement type,since its strain value was lower compared to those of the other structures.

关键词： asphalt pavement strain duration curve load position vehicle speed fiber Bragg grating optical sensors