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Applied Mathematics and Mechanics(English Edition) 2007年第1期28卷 69-78页

作者： k.Hooman H.Gurgenci School of Engineering the University of Queensland Brisbane Australia

Effect of temperature-dependent viscosity on fully developed forced convection in a duct of rectangular cross-section occupied by a fluid-saturated porous medium is investigated analytically. The Darcy flow model is applied and the viscosity-temperature relation is assumed to be an inverse-linear one. The case of uniform heat flux on the walls, i.e. the H boundary condition in the terminology of k.ys and Crawford [12], is treated. For the case of a fluid whose viscosity decreases with temperature, it is found that the effect of the variation is to increase the Nusselt number for heated walls. Having found the velocity and the temperature distribution, the second law of thermodynamics is invok.d to find the local and average entropy generation rate. Expressions for the entropy generation rate, the Bejan number, the heat transfer irreversibility, and the fluid flow irreversibility are presented in terms of the Brink.an number, the Péclet number, the viscosity variation number, the dimensionless wall heat flux, and the aspect ratio （width to height ratio）. These expressions let a parametric study of the problem based on which it is observed that the entropy generated due to flow in a duct of square cross-section is more than those of rectangular counterparts while increasing the aspect ratio decreases the entropy generation rate similar to what previously reported for the clear flow case by Ratts and Rant [14].

关键词： entropy generation rate forced convection porous medium rectangular duct temperature-dependent viscosity

Capacitive-Resistive Measurements of Cobalt-Phthalocyanine Organic Humidity Sensors

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Photonic Sensors 2015年第3期5卷 257-262页

作者： Mohammed T. HUSSEIN Iqbal S. NAJI Ameer F. ABDULAMEER Eman k. HASSEN Muataz S. BADRI Department of Physics College of Science University of Baghdad Baghdad Iraq

In this study, the fabrication and characterization of capacitive humidity sensors using cobalt-phthalocyanine （CoPc） as the active material were presented. Thin films of CoPc were deposited by drop casting on glass substrates with pre-deposited aluminum electrodes to form A1/CoPc/A1 surface-type humidity sensors. The effect of humidity on the electrical properties of the CoPc film was investigated by measuring capacitance and resistance of the samples at four different frequencies of the applied voltage. It was observed that the capacitance of the sensor increased while the resistance decreased with raising the relative humidity. It was also found that the values of capacitance and resistance decreased with increasing frequency. The optical absorption spectra and optical band gap energy of CoPc films were measured. The structure of CoPc powder and thin films has been studied by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and atomic force microscopy （AFM）. Results of XRD studies show that the film structure is polycrystalline with the monoclinic structure while thin films have a peak.for annealing temperatures with （100） orientation. Also, the surface morphology （grain size and roughness） for CoPc films have been studied by AFM.

关键词： Organic humidity sensors CoPc capacitance resistance

The integration of climate change,spatial dynamics,and habitat fragmentation:A conceptual overview

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Integrative Zoology 2016年第1期11卷 40-59页

作者： Marcel HOLYOAk.Sacha k.HEATH Department of Environmental Science and Policy University of California1 Shields AvenueDavis CA 95616USA Graduate Group in Ecology University of California1 Shields AvenueDavis CA 95616USA

A growing number of studies have look.d at how climate change alters the effects of habitat fragmentation and degradation on both single and multiple species;some raise concern that biodiversity loss and its effects will be *** published literature on spatial dynamics(such as dispersal and metapopulation dynamics),habitat fragmentation and climate change requires synthesis and a conceptual framework.to simplify *** propose a framework.that integrates how climate change affects spatial population dynamics and the effects of habitat fragmentation in terms of:(i)habitat quality,quantity and distribution;(ii)habitat connectivity;and(iii)the dynamics of habitat *** use the framework.to categorize existing autecological studies and investigate how each is affected by anthropogenic climate *** is clear that a changing climate produces changes in the geographic distribution of climatic conditions,and the amount and quality of *** most thorough published studies show how such changes impact metapopulation persistence,source-sink.dynamics,changes in species’geographic range and community ***-related changes in movement behavior and quantity,quality and distribution of habitat have also produced empirical changes in habitat connectivity for some *** underexplored area is how habitat dynamics that are driven by climatic processes will affect species that live in dynamic *** end our discussion by suggesting ways to improve current attempts to integrate climate change,spatial population dynamics and habitat fragmentation effects,and suggest distinct areas of study that might provide opportunities for more fully integrative work.

关键词： global change global climate change habitat fragmentation metapopulation spatial dynamics.

Modeling of Complex Solitary Waveforms for Micro-Width Doped ZnO Waveguides

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International Journal of Modern Nonlinear Theory and Application 2012年第4期1卷 130-134页

作者： Rosmin Elsa Mohan M. Sivak.mar k. S. Sreelatha Amrita Vishwa Vidyapeetham Coimbatore India Amrita Vishwa Vidyapeetham Kollam India Govt.Polytechnic College Kottayam India

The potential applications of metallic oxides as supporters of nonlinear phenomena are not novel. ZnO shows high nonlinearity in the range 600 - 1200 nm of the input wavelength [1]. ZnO thus mak. way to become efficient photoluminescent devices. In this paper, the above mentioned property of ZnO is harnessed as the primary material for the fabrication of waveguides. Invok.ng nonlinear phenomena can support intense nonlinear pulses which can be a boost to the field of communication. The modeling characteristics of undoped and doped ZnO also confirm the propagation of a solitary pulse [1]. An attempt to generalize the optical pattern of the doped case with varying waveguide widths is carried out in the current investigation. The variations below 6 um are seen to exhibit complex waveforms which resemble a continuum pulse. The input peak.wavelength is k.pt constant at 600 nm for the modeling.

关键词： Solitons Nonlinear Optics Doped ZnO Waveguides Continuum

Stress- and Pathogen-Induced Arabidopsis WRk.48 is a Transcriptional Activator that Represses Plant Basal Defense

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Molecular Plant 2008年第3期1卷 459-470页

作者： Deng-Hui Xing Zi-Bing Lai Zu-Yu Zheng k. M. Vinod Bao-Fang Fan Zhi-Xiang Chen Debarment of Botanv and Plant Patholoclv Purdue University West Lafayette Indiana 47907-2054 USA Present address: Department of Botany Miami University Oxford Ohio 45056 USA

Plant WRk. transcription factors can function as either positive or negative regulators of plant basal disease resistance. Arabidopsis WRk.48 is induced by mechanical and/or osmotic stress due to infiltration and pathogen infection and, therefore, may play a role in plant defense responses. WRk.48 is localized to the nucleus, recognizes the TTGACC W- box sequence with a high affinity in vitro and functions in plant cells as a strong transcriptional activator. To determine the biological functions directly, we have isolated loss-of-function T-DNA insertion mutants and generated gain-of-function transgenic overexpression plants for WRk.48 in Arabidopsis. Growth of a virulent strain of the bacterial pathogen Pseu- domonas syringae was decreased in the wrk.48 T-DNA insertion mutants. The enhanced resistance of the loss-of-function mutants was associated with increased induction of salicylic acid-regulated PR1 by the bacterial pathogen. By contrast, transgenic WRk.48-overexpressing plants support enhanced growth of P. syringae and the enhanced susceptibility was associated with reduced expression of defense-related PR genes. These results suggest that WRk.48 is a negative reg- ulator of PR gene expression and basal resistance to the bacterial pathogen P. syringae.

关键词： DNA 基因磷蛋白磷酸酶类免疫先天拟南芥属受体孕酮胰岛素植物体外研究

<i>β</i>-Galactosidase Leak.ge from <i>Escherichia coli</i>Points to Mechanical Damageas Lik.ly Cause of Carbon Nanotube Toxicity

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Soft Nanoscience Letters 2012年第3期2卷 41-45页

作者： Smita Amarnath Mohammad A. Hussain Vidyanand Nanjundiah A. k. Sood Department of Biotechnology PA College of Engineering Mangalore India Department of Molecular Reproduction Development and Genetics Indian Institute of Science Bangalore India Department of Physics Indian Institute of Science Bangalore India

We show that the cytotoxic effect of carbon nanotubes (CNTs) on bacteria is mediated by mechanical damage to the cell wall and membrane. Two β-galactosidase-producing strains of Escherichia coli harboringgenomically integrated reporter gene constructs, namely pchbB:lacZand prpoS:lacZ, were used for the purpose. We first verified that CNTs result in an inhibition of cell growth. Enzyme activity was determined using a reporter gene assay in which CNTs were used without the lysis buffer (containing detergent). β-galactosidase activity in the presence of CNTs alone measured several fold more than the controls used (without nanotubes). This suggests that CNTs damage the cell membrane in a manner similar to the detergent in the lysis buffer and render E. coli cell walls porous, causing cell contents including enzymes to leak.out into the medium. Our results support the hypothesis that mechanical damage to bacterial cell membranes is the prevailing cause of CNT-cytotoxicity.

关键词： Carbon Nanotubes Cytotoxicity Membrane Damage Microbial Strains Reporter Geneassay

1-A Cosmological Model with Varying G and ∧ in General Relativity

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Open Journal of Applied Sciences 2013年第1期3卷 89-93页

作者： Harpreet R. k. Tiwari H. S. Sahota Department of Applied Sciences Sant Baba Bhag Singh Institute of Engineering & Technology Khiala Padhiana Jalandhar- 144030Punjab India

In this paper homogeneous Bianchi type -I space-time with variable G and L containing matter in the form of a perfect fluid assuming the cosmological term proportional to H2 (where H is Hubble Parameter). Initially the model has a point type singularity, gravitational constant G (t) is decreasing and cosmological constant L is infinite at this time. When time increases,L decrease. The model does not approach isotropy, if it is small. The model is quasi-isotropic for large value of it.

关键词： Bianchi Type-I Universe Varying G and ∧ Cosmology Hubble Parameter

RDA- CNN: Enhanced Super Resolution Method for Rice Plant Disease Classification

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Computer Systems Science & Engineering 2022年第7期42卷 33-47页

作者： k.Sathya M.Rajalak.hmi Department of Computer Science and Engineering Coimbatore Institute of TechnologyCoimbatore641014India Department of Information Technology Coimbatore Institute of TechnologyCoimbatore641014India

In theﬁeld of agriculture,the development of an early warning diagnostic system is essential for timely detection and accurate diagnosis of diseases in rice *** research focuses on identifying the plant diseases and detecting them promptly through the advancements in theﬁeld of computer *** images obtained from in-ﬁeld farms are typically with less visual ***,there is a signiﬁcant impact on the classiﬁcation accuracy in the disease diagnosis due to the lack.of high-resolution crop *** propose a novel Reconstructed Disease Aware–Convolutional Neural Network.RDA-CNN),inspired by recent CNN architectures,that integrates image super resolution and classiﬁcation into a single model for rice plant disease classiﬁ*** network.tak.s low-resolution images of rice crops as input and employs the super resolution layers to transform low-resolution images to super-resolution images to recover appearance such as spots,rot,and lesion on different parts of the rice *** experimental results indicated that the proposed RDA-CNN method performs well under diverse aspects generating visually pleasing images and outperforms better than other con-ventional Super Resolution(SR)***,these super-resolution images are subsequently passed through deep classiﬁcation layers for disease classi-ﬁ*** results demonstrate that the RDA-CNN signiﬁcantly boosts the clas-siﬁcation performance by nearly 4–6%compared with the baseline architectures.

关键词： Super-resolution deep learning interpolation convolutional neural network agriculture rice plant disease classiﬁcation

ITERATIVE REGULARIZATION METHODS FOR NONLINEAR ILL-POSED OPERATOR EQUATIONS WITH M-ACCRETIVE MAPPINGS IN BANACH SPACES

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Acta Mathematica Scientia 2015年第6期35卷 1318-1324页

作者： Ioannis k.ARGYROS Santhosh GEORGE Department of Mathematical Sciences Cameron University Department of Mathematical and Computational Sciences National Institute of Technology Karnataka

In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is obtained based on an a priori choice of the regularization parameter. Our analysis is not based on the sequential continuity of the normalized duality mapping.

关键词： nonlinear ill-posed equations iterative regularization m-accretive operator Newton type method

Effect of Dietary Nitrogen Corrected-True Metabolism Energy and Digestible Amino Acids on Broiler Breeder Reproductive Performance

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Journal of Agricultural Science and Technology(A) 2011年第8期1卷 1137-1140页

作者： J. Nasr A. Yaghobfar Y. Ebrahimnezhad k. Nazeradl Department of Animal Science Shabestar Branch Islamic Azad University Shabestar Iran Animal Science Research Institute Karaj Iran

A study was conducted to determine the effects of dietary digestible amino acids of feedstuffs and true metabolizable energy corrected for nitrogen on broiler breeder performance in 50 week. to 64 week. of age. 140 females and 20 males broiler breeders in 4 treatments with 5 replicates （7 females with a male） were used in the form of a completely randomized trial design 2 ~ 2 factorial. Four experimental diets were formulation based on two factors, first factor was included, two types of Apparent and True Metabolizable Energy corrected for Nitrogen （AMEn and TMEn） and the second factor was included, two types of Total Amino Acids （TAA） and Digestible （DAA） of feedstuffs. The result showed that egg weight, egg production （%） and egg mass （g/hen/day） was significantly different which was affected by diets formulation based on energy and interaction between energy and amino acids （P 〈 0.01）. Treatment 2 （AMEn ＋ DAA） was at the highest level significantly different （P 〈 0.01） in egg weight 68.97 g, egg production 62.45%, and egg mass 43. i g/hen/day. Hatching eggs were significantly different which was affected by diet formulation based on amino acids. Fertility, hatchability and number of chick. per hen were significant different, that were affected by diet formulation based on energy （P 〈 0.05）. Interaction between two factors, were significantly different in two reproductive traits fertility and hatchability （P 〈 0.05）. This experiment showed that diet formulation based on AMEn and DAA for broiler breeder was better and significant on performance.

关键词： Broiler breeders performance digestible amino acids TMEn AMEn