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Browse silage as potential feed for captive wild ungulates in southern Africa:A review

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Animal Nutrition 2018年第1期4卷 1-10页

作者： Khanyisile R.Mbatha Archibold g.Bakare University of South Africa Department of Agriculture and Animal Health Fiji National University College of AgricultureFisheries and Forestry

The objective of the review was to assess the potential of indigenous browse trees as sustainable feed supplement in the form of silage for captive wild *** attempts to use silage as feed in zoos in temperate regions have been conducted with *** on silage from the indigenous browse trees preferred by wild ungulates in southern Africa is *** use of silage from the browse trees is of interest as it has potential to reduce or replace expensive feed sources(pellets,fruits and farm produce) currently offered in southern African zoos,game farms and reserves,especially during the colddry *** leaf biomass from the indigenous browse trees can be produced for silage *** nutrient content and minerals from indigenous browsable trees are highly *** browse trees have low water-soluble carbohydrates(WSC) that render them undesirable for *** such as wilting browse leaves,mixing cereal crops with browse leaves,and use of additives such as urea and enzymes have been studied extensively to increase WSC of silage from the indigenous browse ***-nutritional factors from the indigenous browse preferred by the wild ungulates have also been studied *** browse silages are a potential feed resource for the captive wild *** the browse trees are used to make silage,they are likely to improve performance of wild ungulates in captivity,especially during the cold-dry season when browse is *** is needed to assess the feasibility of sustainable production and the effective use of silage from indigenous browse trees in southern *** intake and nutrient utilisation and reducing the concentrations of anti-nutritional compounds in silage from the indigenous browse trees of southern Africa should be the focus for animal nutrition research that need further investigation.

关键词： Anti-nutritional factors Indigenous browsable trees Nutritive value Silage Ungulates

Prey and predators perceive orb-web spider conspicuousness differently: evaluating alternative hypotheses for color polymorphism evolution

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Current Zoology 2019年第5期65卷 559-570页

作者： Nathalia g.XIMENES Felipe M.gAWRYSZEWSKI Animal Colouration and Evolution Lab Departamento de ZoologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaBrasiliaDF70910-900Brazil Pos-graduaqao em Ecologia e Evoluqao Universidade Federal de GoiasCampus SamambaiaGoianiaGO74690-900Brazil

Color polymorphisms have been traditionally attributed to apostatic *** perception of color depends on the visual system of the *** models predict that differently perceived degrees of conspicuousness by two predator and prey species may cause the evolution of polymorphisms in the presence of anti-apostatic and apostatic *** spider gasteracantha cancriformis(Araneidae)possesses several conspicuous color *** orb-web spiders,the prey attraction hypothesis states that conspicuous colors are prey lures that increase spider foraging success via flower ***,polymorphism could be maintained if each morph attracted a different prey species(multiple prey hypothesis)and each spider mimicked a different flower color(flower mimicry hypothesis).Conspicuous colors could be a warning signal to predators because of the spider's hard abdomen and *** predators could perceive morphs differently and exert different degrees of selective pressures(multiple predator hypothesis).We explored these 3 hypotheses using reflectance data and color vision modeling to estimate the chromatic and achromatic contrast of *** morphs as perceived by several potential prey and predator *** results revealed that individual taxa perceive the conspicuousness of morphs ***,the multiple prey hypothesis and,in part,the multiple predator hypothesis may explain the evolution of color polymorphism in ***,even in the presence of anti-apostatic *** flower mimicry hypothesis received support by color metrics,but not by color vision *** parameters not evaluated by color vision models could also affect the perception of morphs and influence morph survival and polymorphism stability.

关键词： aposematism Araneidae gasteracantha cancriformis luring prey attraction visual communication

Effects of target pre-heating and expansion on terahertz radiation production from intense laser-solid interactions

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High Power Laser Science and Engineering 2014年第1期2卷 13-17页

作者： X.H.Yuan Y.Fang D.C.Carroll D.A.MacLellan F.Du N.Booth M.Burza M.Chen R.j.gray Y.F.jin Y.T.Li Y.Liu D.Neely H.Powell g.Scott C.-g.Wahlstrm j.Zhang P.McKenna Z.M.Sheng Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy Shanghai Jiao Tong University Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences SUPA Department of Physics University of Strathclyde Central Laser Facility Rutherford Appleton Laboratory Department of Physics Lund University

The first experimental measurements of intense(～7 × 1019 W cm-2) laser-driven terahertz(THz) radiation from a solid target which is preheated by an intense pulse of laser-accelerated protons is reported. The total energy of the THz radiation is found to decrease by approximately a factor of 2 compared to a cold target reference. This is attributed to an increase in the scale length of the preformed plasma, driven by proton heating, at the front surface of the target,where the THz radiation is generated. The results show the importance of controlling the preplasma scale length for THz production.

关键词： target heating terahertz radiation

Local Fourier Analysis for Edge-Based Discretizations on Triangular grids

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 78-96页

作者： Carmen Rodrigo Francisco Sanz Francisco j.gaspar Francisco j.Lisbona Department of Applied Mathematics University of ZaragozaC/Maria de Luna 350018ZaragozaSpain BIFI University of Zaragoza C/Pedro Cerbuna 1250009ZaragozaSpain Department of Applied Mathematics University of ZaragozaC/Pedro Cerbuna 1250009ZaragozaSpain

In this paper,we present a local Fourier analysis framework for analyzing the different components within multigrid solvers for edge-based discretizations on triangular *** different stencils associated with edges of different orientation in a triangular mesh make this analysis *** resulting tool is demonstrated for the vector Laplace problem discretized by mimetic finite difference *** from the local Fourier analysis,as well as experimentally obtained results,are presented to validate the proposed analysis.

关键词： Multigrid local Fourier analysis edge-based discretizations mimetic finite differences

Classification of Multi-view Digital Mammogram Images Using SMO-WkNN

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Computer Systems Science & Engineering 2023年第8期46卷 1741-1758页

作者： P.Malathi g.Charlyn Pushpa Latha Department of Computer Science and Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(Deemed to be University)ChennaiTamilnaduIndia Department of Information Technology Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(Deemed to be University)ChennaiTamilnaduIndia

Breast cancer(BCa)is a leading cause of death in the female population across the *** 2.3 million new BCa cases are recorded globally in females,overtaking lung cancer as the most prevalent form of cancer to be ***,the mortality rates for cervical and BCa are significantly higher in developing nations than in developed *** diagnosis is the only option to minimize the risks of *** learning(DL)-based models have performed well in image processing in recent years,particularly convolutional neural network(CNN).Hence,this research proposes a DL-based CNN model to diagnose BCa from digitized mammogram *** main objective of this research is to develop an accurate and efficient early diagnosis model for BCa *** proposed model is a multi-view-based computer-aided diagnosis(CAD)model,which performs the diagnosis of BCa on multi-views of mammogram images like medio-lateral-oblique(MLO)and cranio-caudal(CC).The digital mammogram images are collected from the digital database for screening mammography(DDSM)*** preprocessing,median filter and contrast limited adaptive histogram equalization(CLAHE)techniques are utilized for image *** preprocessing,the segmentation is performed using the region growing(Rg)*** feature extraction is carried out from the segmented images using a pyramidal histogram of oriented gradients(PHOg)and the AlextNet ***,the classification is performed using the weighted k-nearest neighbor(WkNN)optimized with sequential minimal optimization(SMO).The classified images are evaluated based on accuracy,recall,precision,specificity,f1-score,and mathews correlation coefficient(MCC).Additionally,the false positive and error rates are *** proposed model obtained 98.57%accuracy,98.61%recall,99.25%specificity,98.63%precision,97.93%f1-score,96.26%MCC,0.0143 error rate,and 0.0075 false positive rate(FPR).Compared to the existing models,the research model ha

关键词： Breast cancer DDSM CLAHE median filter region growing PHOg AlexNet SMO-WkNN

A FLEXIBLE PRECONDITIONED ARNOLDI METHOD FOR SHIFTED LINEAR SYSTEMS

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journal of Computational Mathematics 2007年第5期25卷 522-530页

作者： g.-D. gu X.-L. Zhou Lei Lin Department of Applied Mathematics Shanghai University of Finance and Economics Shanghai 200433 China Department of Mathematics Shanghai University Shanghai 200436 China

We are interested in the numerical solution of the large nonsymmetric shifted linear system, （A ＋ αI）x -= b, for many different values of the shift a in a wide range. We apply the Saad＇s flexible preconditioning technique to the solution of the shifted systems. Such flexible preconditioning with a few parameters could probably cover all the shifted systems with the shift in a wide range. Numerical experiments report the effectiveness of our approach on some problems.

关键词： Shifted linear systems 65F10 65Y20. Arnoldi method Flexible preconditioning

Chromatic Uniqueness of Certain Complete Tripartite graphs

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Acta Mathematica Sinica,English Series 2011年第5期27卷 919-926页

作者： g. C. LAU Y. H. PENg Faculty of Computer & Mathematical Sciences Universiti Teknologi MARA (Segamat Campus) 85100 Segamat Johor Malaysia Department of Mathematics and Institute for Mathematical Research Universiti Putra Malaysia 43400 UPM Serdang Malaysia

Let P（g,A） be the chromatic polynomial of a graph g. A graph g is chromatically unique if for any graph H, P（H, λ） = P（g, λ） implies H is isomorphic to g. Liu et al. [Liu, R. Y., Zhao, H. X., Ye, C. F.： A complete solution to a conjecture on chromatic uniqueness of complete tripartite graphs. Discrete Math., 289, 175 179 （2004）], and Lau and Peng [Lau, g. C., Peng, Y. H.： Chromatic uniqueness of certain complete t-partite graphs. Ars Comb., 92, 353-376 （2009）] show that K（p - k,p - i,p） for i = 0, 1 are chromatically unique if p ≥ k ＋ 2 ≥ 4. In this paper, we show that if 2 〈 i 〈 4, the complete tripartite graph K（p - k,p - i,p） is chromatically unique for integers k ≥ i and p 〉 k2/4 ＋ i ＋ 1.

关键词： Complete tripartit graphs chromatic polynomial chromatic uniqueness

Nonlinear optimal control of rotating flexible shaft in active magnetic bearings

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Science China(Technological Sciences) 2011年第5期54卷 1084-1094页

作者： g. S. TOMBUL S. P. BANKS Department of Automatic Control & Systems Engineering The University of Sheffield

The optimal control of nonlinear systems has been studied for years by many researchers. However, the application of optimal control problem to nonlinear non-affine systems needs more attention. In this paper we propose an optimal control design technique for a class of nonlinear and control non-affine equations. The dynamic equations of a flexible shaft supported by a pair of active magnetic bearings (AMBs) are used as the nonlinear control non-affine equations. Mathematical model for the flexible beam is chosen to be the well known Timoshenko beam model, which takes rotary inertia and shear deformations into account, and it is assumed that the shaft is supported by two frictionless bearings at the ends. The effective control of such systems is extremely important for very high angular velocity shafts which are a feature of many modern machines. The control must be able to cope with unbalanced masses and hence be very robust. We shall approach the problem by discretising the Timoshenko beam model and using standard difference formulae to develop a finite-dimensional model of the system. Then we use a recently developed technique for controlling nonlinear systems by reducing the problem to a sequence of linear time-varying (LTV) systems. An optimal control designed for each approximating linear, time-varying system and recent results show that this method will converge uniformly on compact time intervals to the optimal solution.

关键词： approximation technique nonlinear optimal control timoshenko beam active magnetic bearings

Analysis on the high‑quality development of nuclear energy under the goal of peaking carbon emissions and achieving carbon neutrality

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碳中和(英文) 2022年第1期1卷 141-152页

作者： Ronghua Chen g.H.Su Kui Zhang School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Striving to peak carbon emissions and achieve carbon neutrality(known as the"Dual-Carbon"goal)is an inevitable requirement for elevating the environmental resource constraints and realizing harmonious coexistence between the mankind and the *** the energy system,nuclear energy offers various advantages,such as high energy density,low carbon emission,strong environmental adaptability and large potential for energy co-generation and *** is one of the supporting energy sources for the transformation and upgradation of the energy system to a clean,efficient and low-carbon *** this paper,the opportunities and challenges for innovation-driven nuclear energy development in the fields of electricity generation,hydrogen production,heat supply and seawater desalination under the goal of"Dual-Carbon"are discussed and ***,the relevant research on improving the safety and economy of the pressurized water reactor(PWR)and sodium-cooled fast reactor(SFR)conducted by the Nuclear THermal-hydraulic research Lab(NuTHeL)of Xi’an jiaotong University is briefly introduced.

关键词： "Dual-Carbon"goal Nuclear energy NuTHeL PWR SFR