检索结果-南通市图书馆

维普期刊数据库

NGD Analysis of Defected Ground and SIW-Matched Structure

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2023年第2期32卷 343-352页

作者： GU Taochen WAN Fayu GE Junxiang Lalléchère Sébastien Rahajandraibe Wenceslas ravelo blaise Nanjing University of Information Science & Technology (NUIST) Université Clermont Auvergne (UCA) CNRS SIGMA Clermont Aix-Marseille University CNRS University of Toulon

A bandpass negative group delay(NGD)passive circuit based on defect ground structure(DGS)and substrate integrated waveguide(SIW)-matched is developed in the paper. The NGD DGS topology is originally built with notched cells associated with self-matched substrate waveguide elements. The DGS design method is introduced as a function of the geometrical notched and SIW via elements. Then, parametric analyses based on full wave 3-D electromagnetic S-parameter simulations were considered to investigate the influence of DGS physical size effects. The design method feasibility study is validated with fully distributed microstrip circuit prototype. Significant bandpass NGD function performances were validated with 3-D simulations and measurements with-1.69 ns negative group delay value around 2 GHz center frequency over 33.7 MHz NGD bandwidth. Insertion loss is 4.37 d B, and reflection loss reaches 41.5 d B.

关键词： Solid modeling Prototypes Electromagnetic waveguides Reflection Passive circuits Delays Frequency measurement

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

波峰型低损耗负群时延微波电路研究

南京信息工程大学学报（自然科学版） 2020年第1期12卷 127-134,I0036页

作者： blaise ravelo 李宁东万发雨葛俊祥南京信息工程大学电子与信息工程学院南京210044

本文提出了一种波峰形状的低损耗微波负群时延微带电路,该电路主要由四条相同的微带传输线,两条相同的耦合微带线以及T形连接器组成.依据等效电路拓扑结构,基于微波电路理论推导出电路的S参数模型以及负群时延公式.利用ADS仿真软件对电... 详细信息

本文提出了一种波峰形状的低损耗微波负群时延微带电路,该电路主要由四条相同的微带传输线,两条相同的耦合微带线以及T形连接器组成.依据等效电路拓扑结构,基于微波电路理论推导出电路的S参数模型以及负群时延公式.利用ADS仿真软件对电路结构进行优化,并进行了实物的加工与测试.测试结果表明:在中心频率1.017 GHz时,电路的最大群时延为-2.46 ns,插入损耗为-2.1 dB以及反射损耗为-13 dB.实测结果与仿真结果以及理论模型结果具有很好的一致性.

关键词：低损耗负群时延耦合微带线 S参数

维普期刊数据库

Protective effects of D-002 on experimentally induced gastroesophageal reflux in rats

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第8期20卷 2085-2090页

作者： Zullyt Zamora Vivian Molina Rosa Mas Yazmin ravelo Yohany Perez Ambar Oyarzabal Department of Pharmacology Centre of Natural ProductsNational Centre for Scientific ResearchHavana 10600Cuba

AIM: To investigate the effects of beeswax alcohols (D-002) on the esophageal damage induced by gastroesophageal reflux (GER) in rats.

关键词： D-002 Beeswax alcohols Esophagitis Gastroesophageal reflux Oxidative stress

Exactly Solvable Schrodinger Equation with Hypergeometric Wavefunctions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2015年第11期3卷 1454-1471页

作者： J.Morales J.García-Martínez J.García-ravelo J.J.Pena Universidad Autónoma Metropolitana-Azc. DCB-Area de FAMASn Pablo 180Mexico CityMéxico Tecnológico de Estudios Superiores de Ixtapaluca División de Ingeniería Informática e Ingeniería BiomédicaCarretera Ixtapaluca Coatepec Km.7Mexico CityMéxico Escuela Superior de Física y Matemáticas IPN-ZacatencoUP Adolfo López MateosMéxico

In this work, the canonical transformation method is applied to a general second order differential equation (DE) in order to trasform it into a Schr?dinger-like DE. Our proposal is based on an auxiliary function g(x) which determines the transformation needed to find exactly-solvable potentials associated to a known DE. To show the usefulness of the proposed approach, we consider explicitly their application to the hypergeometric DE with the aim to find quantum potentials with hypergeometric wavefunctions. As a result, different potentials are obtained depending on the choice of the auxiliary function;the generalized Scarf, Posh-Teller, Eckart and Rosen-Morse trigonometric and hyperbolic potentials, are derived by selecting g(x) as constant and proportional to the P(x) hypergeometric coefficient. Similarly, the choices g(x)~P(x)/x2 and g(x)~x2/P(x) give rise to a class of exactly-solvable generalized multiparameter exponential-type potentials, which contain as particular cases the Hulthén, Manning-Rosen and Woods-Saxon models, among others. Our proposition is general and can be used with other important DE within the frame of applied matematics and physics.

关键词： Canonical Transformation Schrodinger-Like Equation Hypergeometric DE Exactly-Solvable Potentials

Dinamic of Bacteria Desnitrificants and Nitrificants in the Rizospheric of Wheat with Slow Release of Fertilizer,Irrigated with Waste or Well Water

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Microbiology 2013年第4期3卷 343-349页

作者： Sandra Grisell Mora-ravelo Francisco Gavi Reyes Jesús Pérez Moreno Juan JoséPena Cabriales Leonardo Tijerina Chávez Made Lourdes de la Isla de Bauer Posgrado en Biología Instituto Tecnológico de Ciudad VictoriaCiudad VictoriaMéxico Programa de Hidrociencias Colegio de PosgraduadosMontecilloMéxico Programa de Edafología Colegio de PosgraduadosMontecilloMéxico Departamento de Biotecnología CINVESTAVIrapuatoMéxico

The study of the paper about the rhizosphere in the transformation of nitrogen compounds can generate knowledge of the microbial and biochemical atmosphere of the rhizosphere of wheat, for the understanding of the dynamics of the N in agricultural zones, with the purpose of optimizing the fertilizer use and increasing the productivity of the cultures. Therefore, the objective of the present work was to know the effect the rhizosphere in the dynamics of the bacterial populations that take part in the cycle of the N in wheat nourished with slow release fertilizer and one commercial, irrigated with waste water or well. Analyses in the soil took place vertisol used in the experiment with the rhizospheric and non rhizospheric fraction. The slow release fertilizer used has a matrix enriched with N and P and is in the process of being patented (it explains in materials and methods). Each fertilizer was evaluated and the combination of the slow release fertilizer with organic fertilizer. The technique of the number most probable was used (MNP) to carry out the quantification of the nitrificants and denitrificants bacteria to the 55, 67 and 97 days after sowing (Dds). The results obtained for the MNP of denitrificants bacteria and Nitrosomonas indicate that the effect average of the types of water, soil and fertilizers, as well as their interaction to each other was not significant (p > 0.05). The effect of the fertilizing type and soil (rhizospheric and non rhizospheric) in the MNP of Nitrobacter was significant (p < 0.05). The tendencies show that the non rhizospheric soil is more favorable for the development of denitrificants bacteria and Nitrobacter, whereas the MNP of Nitrosomonas was greater in rhizospheric soil.

关键词： Nitrificants Vermicompost Nitrites Nitrates Ammonium

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于IU型耦合微带线的负群时延电路研究

基于IU型耦合微带线的负群时延电路研究

2020年全国微波毫米波会议

作者：顾韬琛万发雨 B.ravelo 南京信息工程大学

本文提出了一种基于IU型耦合微带线的低损耗负群时延电路,该电路由两条互相耦合的微带线组成。通过建立该电路的等效电路拓扑结构,并基于微波电路理论推导出电路的S参数模型以及群时延的表达式。实测结果与仿真结果以及理论模型具有良... 详细信息

本文提出了一种基于IU型耦合微带线的低损耗负群时延电路,该电路由两条互相耦合的微带线组成。通过建立该电路的等效电路拓扑结构,并基于微波电路理论推导出电路的S参数模型以及群时延的表达式。实测结果与仿真结果以及理论模型具有良好的一致性,证明了该电路具有带通负群时延的特性。实验结果表明:在中心频率1.71GHz时,电路的最大负群时延约为-2ns,带宽为35MHz,插入损耗为-2dB以及反射损耗为-13dB,具有较低的插入损耗和良好的反射损耗。

关键词：带通负群时延电磁干扰耦合微带线

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

大豆—天气分析模式

气象科技 1981年第6期 31-32页

作者： A.C.拉维洛(ravelo) W.L.德克尔(Decker) 王石立

1.引言作物-天气的定量关系可以通过生理学的模式、统计学的模式或二者结合而得到。“作物-天气分析模式”属于后一种类型。本文利用贝尔(Baier,1973)和罗伯逊(Robertson,1974)提出的相类似的方法,应用的模式定义为两个或多个函数的乘... 详细信息

1.引言作物-天气的定量关系可以通过生理学的模式、统计学的模式或二者结合而得到。“作物-天气分析模式”属于后一种类型。本文利用贝尔(Baier,1973)和罗伯逊(Robertson,1974)提出的相类似的方法,应用的模式定义为两个或多个函数的乘积。这些函数各自代表某一特定的作物反应(即产量)与所选取变量的变化之间的关系(贝尔,1973)。这些变量是随作

关键词：环境变量土壤水分生物气象土壤水土壤成分可决系数标准误差中误差迭代回归大豆分析模式天气

Violence Towards Migrants

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Psychology Research 2018年第8期8卷 355-366页

作者： Patricia Martinez Lanz Maria Domenica ravelo Ladron de Guevara Daniela Ayari Moreno Landeta Maria Fernanda Gen Lortia Ixchel Aditi Gonzalez Gutierrez Elsa Paulina Alanis Cazares Universidad Anauac Mexico Mexico City Mexico