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A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte carlo methods

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Nuclear Science and Techniques 2016年第3期27卷 31-39页

作者： e.e.ermis F.B.Pilicer e.Pilicer c.celiktas Physics Department Faculty of ScienceEge University Physics Department Faculty of Arts and ScienceUludag University

The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GeANT4 Monte carlo(Mc) methods and XcOM program in this *** coefficients were also compared with the National Institute of Standards and Technology(NIST) *** results were highly in accordance with each other and NIST *** results showed that FLUKA was quite convenient in comparison to GeANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.

关键词：质量衰减系数蒙特卡洛方法 Geant4 部位 NIST 美国国家标准能量计算眼晶状体

On Quasi-Reduced Quadratic Forms

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Acta Mathematica Sinica,english Series 2010年第8期26卷 1425-1448页

作者： e. DUBOIS c. LeVeSQUe eugene Dubois UMR 6138 CNRS Dep. de mathematiques et mecanique BP 5186 U. de Caen Basse-Normandie 14032 Caen France claude Levesque CICMA et Departement de mathematiques et de statistique U. Laval Quebec P. Qudbec Canada G1K 7P4

With the help of continued fractions, we plan to list all the elements of the set Q△ = {aX2 ＋ bXY ＋ cY2 ： a,b, c ∈Z, b2 - 4ac = △ with 0 ≤ b 〈 √△}of quasi-reduced quadratic forms of fundamental discriminant △. As a matter of fact, we show that for each reduced quadratic form f = aX2 ＋ bXY ＋ cY2 = （a, b, c） of discriminant △〉0（and of sign σ（f） equal to the sign of a）, the quadratic forms associated with f and defined by {〈a＋bu＋cu2,b＋2cu.c〉},with 1≤σ（f）u≤b/2｜c｜（whenever they exist）, 〈c,-b-2cu,a＋bu＋cu2〉 with b/2｜c｜≤σ（f）u≤[w（f）]=[b＋√△/2｜c｜], are all different from one another and build a set I（f） whose cardinality is #I（f）={1＋[ω（f）],when（2c）｜b,[ω（f）],when （2c）｜b. If f and g are two different reduced quadratic forms, we show that I（f） ∩ I（g） = Ф. Our main result is that the set Q△ is given by the disjoint union of all I（f） with f running through the set of reduced quadratic forms of discriminant △〉0. This allows us to deduce a formula for #（Q△） involving sums of partial quotients of certain continued fractions.

关键词： Quadratic forms reduced forms equivalence of forms class numbers quadratic fields,continued fractions

eRROR ANALYSIS OF A STABILIZeD FINITe eLeMeNT MeTHOD FOR THe GeNeRALIZeD STOKeS PROBLeM

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Journal of computational Mathematics 2020年第2期38卷 254-290页

作者： Huoyuan Duan Roger c.e.Tan School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Department of Mathematics National University of SingaporeSingapore

This paper is devoted to the establishment of sharper a priori stability and error estimates of a stabilized finite element method proposed by Barrenechea and Valentin for solving the generalized Stokes problem,which involves a viscosity v and a reaction consta nt *** the establishmen t of sharper st ability estimates and the help of ad hoc finite element projections,we can explicitly establish the dependence of error bounds of velocity and pressure on the viscosity z/,the reaction constant cr,and the mesh size *** analysis reveals that the viscosity y and the reaction constant a respectively act in the numerator position and the denominator position in the error estimates of velocity and pressure in standard norms without any ***,the stabilization method is indeed suitable for the generalized Stokes problem with a small viscosity u and a large reaction constant *** sharper error estimates agree very well with the numerical results.

关键词： Generalized Stokes equations Stabilized finite element method error estimates.

chemical forms and extractability of iron in sediments of three contrasting lakes of china and UK

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Journal of environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson c.e.,Stewart B.M. Key Laboratory of Terrestrial ecological Process Institute of Applied ecology chinese Academy of Sciences Department of Agricultural and environmental Science Queen's University Belfast Shenyang 110016 china Newforge Lane Belfast BT9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. extractability of iron in sediments of West Lake and Taihu Lake in china and Lower Lough erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L Hcl DTPA+TeA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L Mgcl 2 = 0.5 mol/L cacl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

Formal methods, statistical debugging and exploratory analysis in support of system development: Towards a verification and validation calculator tool

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International Journal of Modeling, Simulation, and Scientific computing 2016年第1期7卷 120-141页

作者： Saikou Y.Diallo Ross gore christopher J.Lynch Jose J.Padilla Virginia Modeling Analysis and Simulation Center Old Dominion University 1030 University Blvd.SuffolkVA 23435USA

In this paper,we propose an approach to formally verify and rigorously validate a simulation system against the specification of the real *** implement the approach in a verification and validation calculator tool that takes as input a set of statements that capture the requirements,internal conditions of the system and expected outputs of the real system and produces as output whether the simulation satisfies the requirements,faithfully represents the internal conditions of the system and produces the expected *** provide a use case to show how subject matter experts can apply the tool.

关键词： Verification and validation formal methods modeling and simulation

Locally primitive cayley graphs of finite simple groups

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Science china Mathematics 2001年第1期44卷 58-66页

作者：方新贵王杰 c.e.Praeger Department of Mathematics Peking University Department of Mathematics The University of Western Australia Perth

A graph Г is said to be G-locally primitive, where G is a subgroup of automorphisms of Г, if the stabiliser Ga of a vertex α acts primitively on the set Г( α ) of vertices of Г adjacent to α. For a finite non-abelian simple group L and a cayley subset S of L, suppose that L ? G ? Aut( L), and the cayley graph Г = cay ( L, S) is G-locally primitive. In this paper we prove that L is a simple group of Lie type, and either the valency of Г is an add prine divisor of |Out(L)|, orL =PΩ 8 + (q) and Г has valency 4. In either cases, it is proved that the full automorphism group of Г is also almost simple with the same socle L.

关键词： finite simple group cayley graph locally primitive quasiprimitive semiregular

Role of composition and grain size in controlling the structure sensitive magnetic properties of Sm substituted nanocrystalline co-Zn ferrites

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Journal of Rare earths 2020年第10期38卷 1069-1075,I0002页

作者： Anil B.Mugutkar Shyam K.gore Umakant B.Tumberphale Vijaykumar V.Jadhav Rajaram S.Mane Sunil M.Patange Sagar e.Shirsath Santosh S.Jadhav Bahirji Smarak Mahavidyalaya Basmath431512MaharashtraIndia Microwave Research Laboratory N.E.S.Science CollegeNanded431601MaharashtraIndia Dnyanopasak Shikshan Mandal's Arts Commerce and Science CollegeJintur431509MaharashtraIndia Guangdong Technion Israel Institute of TechnologyShantou 515006China Department of Physics Shivaji MahavidyalayaUdgir-413517MaharashtraIndia School of Physical Sciences Swami Ramanand Teerth Marathwada UniversityNanded431606MaharashtraIndia Shri Krishna Mahavidyalaya Gunjoti413613MaharashtraIndia School of Materials Science and engineering University of New South WalesSydney2052NSWAustralia

The nanocrystalline samarium substituted co-Zn ferrites with chemical formula co0.7Zn0.3SmyFe2-yO4(where y=0,0.01,0.02,0.03,0.04) were synthesized by sol-gel autocombustion *** analysis of Xray diffractograms(XRD) reveals the formation of cubic spinel *** planes indexed from XRD analyses were confirmed in the selected area electron diffraction(SAeD) image of the *** nature of the particles in the ferrite samples was confirmed by *** morphology was analyzed by scanning electron microscopy(SeM).Magnetic measurements show an increase in the magnetization for x ≤*** decrease in magnetization due to spin canting is observed for x=*** coercivity depends on Sm3+doping concentration,grain size and saturation *** complex permeability of the ferrites was analyzed as the function of frequency and Sm3+composition(y).The real part of complex permeability varies linearly with the grain size.

关键词： Nanocrystalline ferrites Rietveld refinement HRTeM Magnetization coercivity Permeability

Bounds on the clique-transversal number of regular graphs

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Science china Mathematics 2008年第5期51卷 851-863页

作者： cHeNG T.c.e Department of Logistics The Hong Kong Polytechnic University

A clique-transversal set D of a graph G is a set of vertices of G such that D meets all cliques of G. The clique-transversal number, denoted τ c (G), is the minimum cardinality of a clique-transversal set in G. In this paper we present the bounds on the clique-transversal number for regular graphs and characterize the extremal graphs achieving the lower bound. Also, we give the sharp bounds on the clique-transversal number for claw-free cubic graphs and we characterize the extremal graphs achieving the lower bound.

关键词： graph regular graph claw-free cubic graph clique-transversal set clique-transversal number 05c65 05c69 05c75

A comparison of visual outcomes in three different types of monofocal intraocular lenses

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International Journal of Ophthalmology(english edition) 2015年第6期8卷 1173-1178页

作者： Vijay Shetty Suhas S Haldipurkar Rujuta gore Rita Dhamankar Anirban Paik Maninder Singh Setia Laxmi eye Institute

AIMTo compare the visual outcomes (distance and near) in patients opting for three different types of monofocal intraocular lens (IOL) (Matrix Aurium, AcrySof single piece, and AcrySof IQ lens).MeTHODSThe present study is a cross-sectional analysis of secondary clinical data collected from 153 eyes (52 eyes in Matrix Aurium, 48 in AcrySof single piece, and 53 in AcrySof IQ group) undergoing cataract surgery (2011-2012). We compared near vision, distance vision, distance corrected near vision in these three types of lenses on day 15 (±3) *** 69% of the eyes in the Matrix Aurium group had good uncorrected distance vision post-surgery; the proportion was 48% and 57% in the AcrySof single piece and AcrySof IQ group (P=0.09). The proportion of eyes with good distance corrected near vision were 38%, 33%, and 15% in the Matrix Aurium, AcrySof single piece, and AcrySof IQ groups respectively (P=0.02). Similarly, The proportion with good “both near and distance vision” were 38%, 33%, and 15% in the Matrix Aurium, AcrySof single piece, and AcrySof IQ groups respectively (P=0.02). It was only the Matrix Aurium group which had significantly better both “distance and near vision” compared with the AcrySof IQ group (odds ratio: 5.87, 95% confidence intervals: 1.68 to 20.56).cONcLUSIONMatrix Aurium monofocal lenses may be a good option for those patients who desire to have a good near as well as distance vision post-surgery.

关键词： visual acuity monofocal lenses cataract surgery