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Phase noise modeling in LC oscillators implemented in siGe technology

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Journal of semiconductors 2013年第2期34卷 60-66页

作者： M.Bouhouche s.Latreche C.Gontrand Universite Mentouri Faculte des Sciences de l'IngenieurDepartement d'ElectroniqueLaboratoire Hyperfrequence & Semi-conducteur(LHS)25000ConstantineAlegria Universite de Lyon VilleurbanneF-69621France

This paper addresses phase noise analysis of a radiofrequency LC oscillator built around a siGe heterojunction bipolar transistor （HBT） realized in a 0.35 um BiCMOs process, as an active device. First, we give a brief background to siGe HBT device physics. The key point is to initiate quantitative analysis on the influence of defects induced during extrinsic base implantation on electric performances of this device. These defects are responsible for the current fluctuations at the origin of low frequency noise in BiCMOs technologies. Next, we investigate the effect of implantation defects as a source of noise in semiconductors on the phase noise of a radiofrequency LC oscillator. We observe their influence on the oscillator phase noise, and we quantify the influence of their energy distribution in the semiconductor gap. second, we give a behavioral model of an LC oscillator con- taining a siGe HBT as an active device. The key goal is to study the susceptibility of a radiofrequency oscillator built around a siGe HBT to phase noise disturbance sources. Based on the time variance behavior of phase noise in oscillators, transient simulations （in the time domain） were used to analyze the time-dependent noise sensitivity of the oscillator.

关键词： siGe heterojunction radiofrequency mixed-mode simulations oscillator phase noise

A Novel Training Algorithm of Genetic Neural Networks and Its Application to Classification

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Journal of systems Engineering and Electronics 2001年第3期12卷 76-84页

作者： Xiao, J. Wu, J. Yang, s. school of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

First of all, this paper discusses the drawbacks of multilayer perceptron (MLP), which is trained by the traditional back propagation (BP) algorithm and used in a special classification problem. A new training algorithm for neural networks based on genetic algorithm and BP algorithm is developed. The difference between the new training algorithm and BP algorithm in the ability of nonlinear approaching is expressed through an example, and the application foreground is illustrated by an example.

关键词： Backpropagation Computer simulation Genetic algorithms Mathematical models Nonlinear control systems Problem solving

Phase-plane analysis of conserved higher-order traffic flow model

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Applied Mathematics and Mechanics(English Edition) 2012年第12期33卷 1505-1512页

作者：吴春秀宋涛张鹏 s.C.WONG shanghai Institute of Applied Mathematics and Mechanics Shanghai University shanghai Key Laboratory of Mechanics in Energy Engineering Department of Civil Engineering The University of Hong Kong

The phase-plane analysis is used to study the traveling wave solution of a recently proposed higher-order traffic flow model under the Lagrange coordinate system. The analysis identifies the types and stabilities of the equilibrium solutions, and the overall distribution structure of the nearby solutions is drawn in the phase plane for the further analysis and comparison. The analytical and numerical results are in agreement, and may help to explain the simulated phenomena, such as the stop-and-go wave and oscillation near a bottleneck. The findings demonstrate the model ability to describe the complexity of congested traffic.

关键词： traffic flow Lagrange coordinates phase-plane analysis traffic congestionpattern

Flavonoids:New Roles for Old Molecules

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Journal of Integrative Plant Biology 2010年第1期52卷 98-111页

作者： Charles s. Buer Nijat Imin Michael A. Djordjevic Genomic Interactions Group ARC Centre of Excellence for Integrative Legume Research Research School of Biology College of Medicine Biology and Environment The Australian National University

Flavonoids are ubiquitous in the plant kingdom and have many diverse functions including defense, UV protection, auxin transport inhibition, allelopathy, and flower coloring. Interestingly, these compounds also have considerable biological activity in plant, animal and bacterial systems - such broad activity is accomplished by few compounds. Yet, for all the research over the last three decades, many of the cellular targets of these secondary metabolites are unknown. The many mutants available in model plant species such as Arabidopsis thaliana and Medicago truncatula are enabling the intricacies of the physiology of these compounds to be deduced. In the present review, we cover recent advances in flavonoid research, discuss deficiencies in our understanding of the physiological processes, and suggest approaches to identify the cellular targets of flavonoids.

关键词： Flavonoids DPBA Figure TTG root

Numerical and analytical investigations of thermosolutal instability in rotating Rivlin-Ericksen fluid in porous medium with Hall current

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Applied Mathematics and Mechanics(English Edition) 2013年第4期34卷 501-522页

作者： s.KUMAR V.sHARMA K.KIsHOR Department of Mathematics Government College Department of Mathematics Himachal Pradesh University Department of Mathematics Government Senior Secondary School

Numerical and analytical investigations of the thermosolutal instability in a viscoelastic Rivlin-Ericksen fluid are carried out in the presence of a uniform vertical magnetic field to include the Hall current with a uniform angular velocity in a porous medium. For stationary convection, the stable solute gradient parameter and the rota- tion have stabilizing effects on the system, whereas the magnetic field and the medium permeability have stabilizing or destabilizing effects on the system under certain condi- tions. The Hall current in the presence of rotation has stabilizing effects for sufficiently large Taylor numbers, whereas in the absence of rotation, the Hall current always has destabilizing effects. These effects have also been shown graphically. The viscoelastic effects disappear for stationary convection. The stable solute parameter, the rotation, the medium permeability, the magnetic field parameter, the Hall current, and the vis- coelasticity introduce oscillatory modes into the system, which are non-existent in their absence. The sufficient conditions for the non-existence of overstability are also obtained.

关键词： magnetic field thermosolutal instability Rivlin-Ericksen rotating fluid Hall current porous medium

Autofluorescence imaging and magnification endoscopy

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World Journal of Gastroenterology 2011年第1期17卷 9-14页

作者： Monalisa Filip sevastita Iordache Adrian sǎftoiu Tudorel Ciurea Research Center of Gastroenterology and Hepatology University of Medicine and PharmacyCraiovaDolj200349Romania

It is well known that angiogenesis is critical in the transition from premalignant to malignant ***,early detection and diagnosis based on morphological changes to the microvessels are *** the last few years,new imaging techniques which utilize the properties of light-tissue interaction have been developed to increase early diagnosis of gastrointestinal(GI) tract *** analyzed several "red-flag" endoscopic techniques used to enhance visualization of the vascular pattern of preneoplastic and neoplastic lesions(*** imaging including autofluorescence imaging,magnifying endoscopy and narrow band imaging).These new endoscopic techniques provide better visualization of mucosal microsurface structure and microvascular architecture and may enhance the diagnosis and characterization of mucosal lesions in the GI *** the near future,it is expected that trimodal imaging endoscopy will be practiced as a standard endoscopy technique as it is quick,safe and accurate for making a precise diagnosis of gastrointestinal pathology,with an emphasis on the diagnosis of early GI tract *** large-scale randomized controlled trials comparing these modalities in different patient subpopulations are warranted before their endorsement in the routine practice of GI endoscopy.

关键词： Angiogenesis Autofluorescence imaging Multiband imaging Narrow band imaging Zoom endoscopy

The human application of gene therapy to re-program T-cell specificity using chimeric antigen receptors

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Chinese Journal of Cancer 2014年第9期33卷 421-433页

作者： Alan D Guerrero Judy s Moyes Laurence JN Cooper Division of Pediatrics The University of Texas MD Anderson Cancer Center The University of Texas Graduate school of Biomedical sciences

The adoptive transfer of T cells is a promising approach to treat cancers. Primary human T cells can be modified using viral and non-viral vectors to promote the specific targeting of cancer cells via the introduction of exogenous T-cell receptors(TCRs) or chimeric antigen receptors(CARs). This gene transfer displays the potential to increase the specificity and potency of the anticancer response while decreasing the systemic adverse effects that arise from conventional treatments that target both cancerous and healthy cells. This review highlights the generation of clinical-grade T cells expressing CARs for immunotherapy, the use of these cells to target B-cell malignancies and, particularly, the first clinical trials deploying the sleeping Beauty gene transfer system, which engineers T cells to target CD19+ leukemia and non-Hodgkin's lymphoma.

关键词： T细胞受体基因治疗异性重新编程抗原嵌合基因转移系统非病毒载体

Evaluation of alternative conceptual models for groundwater modelling

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Geoscience Frontiers 2017年第3期8卷 437-443页

作者： Yangxiao Zhou H.M.P.s.D.Herath UNEsCO-IHE Institute for Water Education

This study evaluates the alternative conceptual models for groundwater modelling. A true model was created with a synthetic alluvial fan-plain hydrogeological framework. Various alternative conceptual models were evaluated for groundwater flow simulations. The first alternative model is a single aquifer layer model; the second alternative model is a 3-layer aquifer model; and the third model is a B-layer model consisting of 3 aquifers separated by 2 aquitards. All models could fit very well to the observa- tions with optimized values of hydraulic conductivities. However, the single aquifer layer model can only compute water balance components with good accuracy. The 3-layer aquifer model can be used for water balance computation and groundwater head simulation with small errors. The 5-layer model is capable of simulating water budget, groundwater head distribution and travel times with high accuracy. Multi- model analysis found only the 3rd alternative model superior.

关键词： Alternative conceptual modelsMulti-model analysisWater budgetTravel time

EXPERIMENT AND sIMULATION FOR THICK-PLATE BENDINGBY HIGH FREQUENCY INDUCTOR

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Acta Metallurgica sinica(English Letters) 1998年第6期11卷 449-455页

作者： s.Imatani Y.Okuno T.Inoue Kyoto Univ Kyoto Japan

In order to produce thick plates with complicated curved surface, a prototype bending machine by the use of high frequency inductor was developed. The bending mechanism is based on the localized stresses which are induced from the difference of temperature in thickness by the high frequency inductor. The operating speed and the thickness of plate were examined from the experiment, and the variation of the temperature was measured. Finite element analysis was carried out in the second part based on the experimentally obtained temperature distribution. The so-called Mindlin plate element was used in order to perform the simulation efficiently. The strategy to produce such curved surface in the practical process was discussed and further perspective of the production system was described. (Edited author abstract) 6 Refs.

关键词： plate bending high frequency inductor die-less forming thermoelasto-plastic deformation finite element method