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Hybrid Active Contour Mammographic Mass Segmentation and Classification

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Computer Systems Science & Engineering 2022年第3期40卷 823-834页

作者： K.Yuvaraj u.S.Ragupathy Department of Electronics and Instrumentation Engineering Kongu Engineering College PerunduraiErode638060India

This research implements a novel segmentation of mammographic *** methods are proposed,namely,segmentation of mass based on iterative active contour,automatic region growing,and fully automatic mask selectionbased active contour *** the first method,iterative threshold is performed for manual cropped preprocessed image,and active contour is applied *** overcome manual cropping in the second method,an automatic seed selection followed by region growing is *** that the result is only a few images owing to over segmentation,the third method uses a fully automatic active *** of the segmentation techniques are compared with the manual markup by experts,specifically by taking the difference in their mean ***,the difference in the mean value of the third method is 1.0853,which indicates the closeness of the ***,the proposed method is compared with the existing fuzzy C means and level set *** automatic mass segmentation based on active contour technique results in segmentation with high *** using adaptive neuro fuzzy inference system,classification is done and results in a sensitivity of 94.73%,accuracy of 93.93%,and Mathew’s correlation coefficient(MCC)of 0.876.

关键词： Feature optimization hybrid active contour segmentation mass classification mass feature extraction medical image analysis

Nucleon effective mass in symmetric nuclear matter from the extended Brueckner-Hartree-Fock approach

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Chinese Physics C 2012年第6期36卷 513-518页

作者：甘胜鑫左维 u.Lombardo Institute of Modern Physics Chinese Academy of Sciences Graduate university of Chinese Academy of Sciences Department of Physics and Astrophysics Catania UniversityVia Santa Sofia 64I-95123 and INFN-LNSVia Santa Sofia 44I-95123 CataniaItaly

We have calculated the nucleon effective mass in symmetric nuclear matter within the framework of the Brueckner-Bethe-Goldstone （BBG） theory, which has been extended to include both the contributions from the ground-state correlation effect and the three-body force （TBF） rearrangement effect. The effective mass is predicted by including the ground-state correlation effect and the TBF rearrangement effect, and we discuss the momentum dependence and the density dependence of the effective mass. It is shown that the effect of ground state correlations plays an important role at low densities, while the TBF-induced rearrangement effect becomes predominant at high densities.

关键词： nucleon effective mass extended BHF approach ground state correlations TBF rearrangementeffect

Simulation of rainfall-runoff and watershed convergence process in the upper reaches of Heihe River Basin,July 2002

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Science China Earth Sciences 2004年第z1期47卷 1-8页

作者： GAO Yanhong L(u) Shihua CHENG Guodong Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The watershed flow concentration scheme in the distributed hydrology-soil- vegetation model (DHSVM) is coupled with the mesoscale atmospheric model MM5 version 3.5, in which the Oregen States university land surface model (OSuLSM) was involved. The flood event which happened in July 2002 in the upper reaches of Heihe river basin is simulated and the surface flow convergence process is shown with this coupled model. It has been concluded that times water head reaches each place of the basin are different. Water amount at each point is split-flow proportionally as the drops in elevation between it and neighbor points. Large part of the water amount pass away in greater slope direction and small part pass away in smaller slope *** of the slope convergence makes the atmospheric model redistributes the surface water laterally.

关键词： distributed hydrology-soil-vegetation model, mesoscale atmospheric model, watershed flow concentration process.

Employment generation in earth sciences through broad-basing of geoscience

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Episodes 2004年第1期27卷 58-59页

作者： u.Aswathanarayana MahadevanInternationalCentreforWaterResourcesManagementHyderabadINDIA

Geoscience instruction in India is facing a serious crisis-instances are known of well-established university geology departments with more than a score of senior teachers having just a couple of ***. students. This profound lack of demand for geoscience studies is a direct consequence of the paucity of employment opportunities for tradition-ally-trained geoscience graduates

关键词：地球科学印度地质学研究

Implications of crude oil pollution on natural regeneration of plant species in an oil-producing community in the Niger Delta Region of Nigeria

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Journal of Forestry Research 2014年第4期25卷 915-921页

作者： u.D Chima G.Vure Department of Forestry and Wildlife Management University of Port Harcourt- Choba P.M.B. 5323 Port Harcourt Rivers State Nigeria

The study evaluated the impact of crude oil pollution on natu- ral regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites--unpolluted site （uS）, polluted and untreated site （PuS）, and polluted and treated site （PTS）-- were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the uS seed bank than in the PuS and PTS seed banks. The highest number of non-woody plants was observed in the uS, followed by the PTS, and then the PuS. Both species richness and diversity of non-woody plants were highest at the uS, followed by the PuS, and lowest in the PTS. Woody species in the uS seed bank were 87.5% and 80% dissimilar with those of the PuS and PTS at 0-10 cm and 10--20 cm respectively. No variation was observed between woody species in the PuS and PTS seed banks. Non-woody species at 0-10 em uS seed bank were 73.08% dissimilar with those of PuS at the two soil depths and 81.48/88.46% dissimilar with those of the 0-10/10-20 cm of the PTS respectively. At 10-20 cm, non-woody species of theuS were 69.66% dissimilar with those from each of the two soil depths in PuS; and 73.91/81.82% dissimilar with those of 0-10/10-20 cm of the PTS respectively. Non-woody species variation between the PuS and PTS was higher at 10-20 cm than 0-10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively af- fected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas.

关键词： Ogoni land crude oil pollution remediation plant regeneration

uniform and L-convergence of Logarithmic Means of Walsh-Fourier Series

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Acta Mathematica Sinica,English Series 2006年第2期22卷 497-506页

作者： G.GáT u.GOGINAVA Institute of Mathematics and Computer Science College of Nyiregyhaza Department of Mechanics and Mathematics Tbilisi State University

The （NSrlund） logarithmic means of the Fourier series of the integrable function f is：1/lnn-1∑k=1Sk（f）/n-k, where ln：=n-1∑k=11/k.In this paper we discuss some convergence and divergence properties of this logarithmic means of the Walsh-Fourier series of functions in the uniform, and in the L^1 Lebesgue norm. Among others, as an application of our divergence results we give a negative answer to a question of Móricz concerning the convergence of logarithmic means in norm.

关键词： Walsh system Norlund logarithmic means Convergence divergence properties

A co-infection model for HPV and syphilis with optimal control and cost-effectiveriess analysis

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International Journal of Biomathematics 2021年第7期14卷 1-44页

作者： A.Omame D.Okuonghae u.E.Nwafor B.u.Odionyenna Department of Mathematics Federal university of Technology OwerriNigeriai Department of Mathematics University of Benin Benin CityNigeria

A co-infection model for human papillomavirus(HPV)and syphilis with cost-effectiveness optimal control analysis is developed and *** full co-infectionmodel is shown to undergo the phenomenon of backward bifurcation when a certain con-dition is *** global asymptotic stability of the disease-free equilibrium of thefull model is shown not to exist when the associated reproduction number is less *** existence of endemic equilibrium of the syphilis-only sub-model is shown toexist and the global asymptotic stability of the disease-free and endemic equilibria of thesyphilis-only sub-model was established,for a special *** analysis is alsocarried out on the parameters of the *** the syphilis associated reproductionnumber,R_(0s),as the response function,it is observed that the five-ranked parametersthat drive the dynamics of the co-infection model are the demographic parameter μ,the efective contact rate for syphilis transmission,β_(s),the progression rate to late stage ofsyphilis σ2,and syphilis treatment rates:τ1 and τ2 for co-infected individuals in com-partments Hi and Hl,***,when the HPV associated reproductionnumber,R0h,is used as the response function,the five most dominant parameters thatdrive the dynamics of the model are the demographic parameter μ,the effective contactrate for HPV transinission,β_(h),the fraction of HPV infected who develop persistent HPV p1,the fraction of individuals vaccinated against incident HPV infection φ and the HPVvaccine eflicacy π*** simulations of the optimal control model showed that theoptimal control strategy which implements syphilis treatment controls for singly infectedindividuals is the most cost-effective of all the control strategies in reducing the burdenof HPV and syphilis co-infections.

关键词： Human papillomavirus syphilis co-infection optimal control cost-effectiveness analysis

Spectroscopic investigations on the effect of humic acid on the formation and solubility of secondary solid phases of Ln_2(CO_3)_3

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Journal of Rare Earths 2011年第6期29卷 516-521页

作者： Stella Antoniou Ioannis Pashalidis Andre Gessner Michael u Kumke Department of Chemistry University of Cyprus P.O. Box 20537 1678 Nicosia Cyprus Chemistry Department/Physical Chemistry University of Potsdam Karl- Liebknecht-Str. 24-25 14476 Potsdam-Golm Germany

The formation of secondary Ln（III） solid phases （e.g., Nd2（CO3）3 and Sm2（CO3）3） was studied as a function of the humic acid concentration in 0.1 mol/L NaClO4 aqueous solution in the neutral pH range （5–6.5）. The solid phases under investigation were prepared by alkaline precipitation under 100% CO2 atmosphere and characterized by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR）, X-ray diffraction （XRD）, time-resolved laser fluorescence spectroscopy （TRLFS）, diffuse reflectance ultraviolet-visible （DR-uV-Vis）, Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicated that Nd2（CO3）3 and Sm2（CO3）3 were stable and remained the solubility limiting solid phases even in the presence of increased humic acid concentration （0.5 g/L） in solution. upon base addition in the Ln（III）-HA system, decomplexation of the previously formed Ln（III）-humate complexes and precipitation of two distinct phases occurred, the inorganic （Ln2（CO3）3） and the organic phase （HA）, which was adsorbed on the particle surface of the former. Nevertheless, humic acid affected the particle size of the solid phases. Increasing humic acid concentration resulted in decreasing crystallite size of the Nd2（CO3）3 and increasing crystallite size of the Sm2（CO3）3 solid phase, and affected inversely the solubility of the solid phases. However, this impact on the solid phase properties was expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.

关键词： lanthanide ions humic acid solid phase solubility Raman TRLFS DR-uV-Vis rare earths

Control of a unified Chaotic System via Single Variable Feedback

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Chinese Physics Letters 2009年第9期26卷 65-68页

作者：郭荣伟 u. E. Vincent Department of Mathematical and Physical Sciences Shandong Institute of Light Industry Jinan 250353 Institute of Theoretical Physics Technical University of Clausthal Arnold-Sommer Str. 6 38678 Clausthal-Zellerfeld Germany Department of Physics Olabisi Onabanjo University Ago-Iwoye Nigeria

Based on the LaSalle invariance principle, we propose a simple adaptive-feedback for controlling the unified chaotic system. We show explicitly with numerical proofs that our method can easily achieve the control of chaos in the unified chaotic system using only a single variable feedback. The present controller, to our knowledge, is the simplest control scheme for controlling a unified chaotic system.

关键词： sea surface nonliear interaction numerical method