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Puziwan Gold Deposit in Shanxi,China:A Special Linear Cryptoexplosive Breccia Type Gold Deposit 被引量:7
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作者 YAN Fengzeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期554-558,共5页
The Puziwan gold deposit is a special linear cryptoexplosive breccia type deposit found in northeastern Shanxi, China, in recent years. The deposit is located in a secondary metallogenic belt of the most famous Au-Ag ... The Puziwan gold deposit is a special linear cryptoexplosive breccia type deposit found in northeastern Shanxi, China, in recent years. The deposit is located in a secondary metallogenic belt of the most famous Au-Ag polymetallic metallogenic belt along the north margin of the North China platform. The secondary metallogenic belt is a synmagmatic tension-shear fault-fracture belt of ENE linear trend. The Indosinian cryptoexplosive breccia body, quartz monzonitic porphyry (beschtauite breccia), quartz monzonite (243.7 Ma, K-Ar), Yanshanian granite-porphyry (105±6 Ma, Rb-Sr) and orebodies mostly occur as dykes or veins and short lenses along the structural fracture belt. The orebodies are emplaced in the fractured cryptoexplosive breccia body in the tectonomagmatic belt and their attitude is consistent with that of the breccia body. The orebodies have two types: one is shallow-seated thick and big ones, which are short-lenticular in plan and wedge-shaped in cross section, shallow buried, large in size and high-grade; the other is lean orebodies, which occur as parallel veins at depths. The ores are mainly of Au-Ag polymetallic sulphide-rich breccia type. Pyrite (limonite) is the dominant metallic mineral, with subordinate chal-copyrite, galena, sphalerite, tenantite, native gold, electrum, native silver and argentite. The gangue minerals consist mainly of quartz and plagioclase, with subordinate carbonate minerals, alunite chalcedony and kaolin. Kaolinization is the characteristic alteration type. Sulphide minerals contain abundant trace minerals such as Cu, Pb, Ag, Sb and Hg, while in the ores Ag, Cu, Pb, Zn, As and Sb are the best indicator element assemblage of Au. The δ34S(%o) values of the ores rane from ?3.2%o to 5.3%o, with average ?0.102%o. The δO H2O(%o) and δ(%o) values are in the ranges from ?3.1%o to 7.73%o and from ?64%o to ?90%o respectively. The Pb isotopic compositions of the rocks and ores in this region indicate that Pb comes from three tectonic sources—upper mantle, lower crust and orogenic belt. The inclusion homogenization temperature are in the ranges of 110 to 220°C and 230 to 310°C, which suggests that the deposit formed under meso-epithermal conditions. The ore-forming pressures range from 6 to 32 MPa and the depths are 230 to 1200 m. In view of the above, the Puziwan gold deposit is genetically ascribed to a high-sulphur (alunite-kaolin) meso-epithermal gold deposit related to subvolcanic rocks. This gold deposit formed during the Indosinian stage (245.9±0.3 Ma) and then was influenced by a thermal event in the Yanshanian stage (142.9±0.5 Ma). 展开更多
关键词 gold deposit linear cryproexplosive breccia type SHANXI
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Ultrasonic beam focusing characteristics of shear-vertical waves for contact-type linear phased array in solid 被引量:2
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作者 Yu-Xiang Dai Shou-Guo Yan Bi-Xing Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期270-276,共7页
We investigate the beam focusing technology of shear-vertical(SV) waves for a contact-type linear phased array to overcome the shortcomings of conventional wedge transducer arrays. The numerical simulation reveals the... We investigate the beam focusing technology of shear-vertical(SV) waves for a contact-type linear phased array to overcome the shortcomings of conventional wedge transducer arrays. The numerical simulation reveals the transient excitation and propagation characteristics of SV waves. It is found that the element size plays an important role in determining the transient radiation directivity of SV waves. The transient beam focusing characteristics of SV waves for various array parameters are deeply studied. It is particularly interesting to see that smaller element width will provide the focused beam of SV waves with higher quality, while larger element width may result in erratic fluctuation of focusing energy around the focal point. There exists a specific range of inter-element spacing for optimum focusing performance. Moreover, good beam focusing performance of SV waves can be achieved only at high steering angles. 展开更多
关键词 beam focusing shear-vertical(SV)waves contact-type linear phased array SOLID
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Improving Linear Type Traits to Improve Production Sustainability and Longevity in Purebred Sahiwal Cattle
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作者 Ashutosh Dubey Sharad Mishra Vikas Khune Pavan K. Gupta Bhooshan K. Sahu Arvind K. Nandanwar 《Journal of Agricultural Science and Technology(A)》 2012年第5期636-639,共4页
In order to determine various traits which need to be improved for improving the productive life span and longevity, purebred Sahiwal cows available at bull mother experimental farm and cattle breeding farm located at... In order to determine various traits which need to be improved for improving the productive life span and longevity, purebred Sahiwal cows available at bull mother experimental farm and cattle breeding farm located at Veterinary College, Durg, Chhattisgarh, India were used. For present investigation, 17 linear type traits were measured, scaled and scored as per the guidelines of International Committee for Animal Recording (2001). The average score point (ASP) under 1-9 point scale score system along with respective observed group for different linear type traits were stature (6.88; taller), chest width (5.30; intermediate), body depth (4.11; intermediate), rump angle (4.27; intermediate), rump width (5.09; intermediate), rear leg set-side view (4.55; intermediate), rear leg set-rear view (5.95; intermediate), foot angle (5.66; intermediate), udder depth (5.71; intermediate), rear udder height (4.90; intermediate), udder balance (5.27; intermediate), udder cleft (3.75; intermediate), fore udder attachment (5.55; intermediate), teat length (3.54; intermediate), fore teat placement (5.33; intermediate), rear teat placement (6.37; intermediate) and teat thickness (2.76; narrow). For most of the traits, ASP which lies near midpoint (i.e. near five) is known to be ideal for dairy type cattle. Moreover, some traits also showed the presence of undesirable ASP. Hence, the traits such as body depth, rump angle, foot angle, udder depth, rear udder height, udder cleft, fore udder attachment, teat length, and teat thickness needs to be improved for improving the production sustainability and herd life of Sahiwal cattle. Thus, present investigation gives explicit clue to incorporate these conformation traits in selection program of this valuable germplasm commonly found in Southern part of Asia (India, Pakistan, Srilanka, etc.). 展开更多
关键词 SAHIWAL linear type traits production sustainability and longevity.
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Actuating mechanism and design of a T-type linear ultrasonic motor
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作者 刘英想 刘军考 +1 位作者 陈维山 石胜君 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期43-46,共4页
To take advantage of merits of higher output-power and efficiency of bolt-clamped transducer,a T-type linear ultrasonic motor was proposed in this paper.The proposed motor contained a horizontal transducer and a verti... To take advantage of merits of higher output-power and efficiency of bolt-clamped transducer,a T-type linear ultrasonic motor was proposed in this paper.The proposed motor contained a horizontal transducer and a vertical transducer.The horizontal transducer included two exponential shape horns,and the vertical transducer contained one exponential shape horn.And the horns intersected at tip ends where a driving foot was located.The longitudinal vibrations of transducers were excited by the stretching vibration of PZT ceramics.Longitudinal vibrations were superimposed in the motor and generated elliptical trajectory at the driving foot.The actuating mechanism of the proposed motor was analyzed.The two working modals of the motor were gained with FEM.The resonant frequencies of two working modals were degenerated by adjusting the structural parameters.The motion trajectory of nodes on the driving foot was gained by transient analysis.The vibration amplitude of node on the driving foot indicates that the proposed motor has potential good output characteristics.The results verify the feasibility of the proposed design and provide instructions for the development of the new ultrasonic motor. 展开更多
关键词 ultrasonic motor linear T-type longitudinal transducer FEM
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Fully Nonlinear Boussinesq-Type Equations with Optimized Parameters for Water Wave Propagation
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作者 荆海晓 刘长根 +1 位作者 龙文 陶建华 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期503-518,共16页
For simulating water wave propagation in coastal areas, various Boussinesq-type equations with improved properties in intermediate or deep water have been presented in the past several decades. How to choose proper Bo... For simulating water wave propagation in coastal areas, various Boussinesq-type equations with improved properties in intermediate or deep water have been presented in the past several decades. How to choose proper Boussinesq-type equations has been a practical problem for engineers. In this paper, approaches of improving the characteristics of the equations, i.e. linear dispersion, shoaling gradient and nonlinearity, are reviewed and the advantages and disadvantages of several different Boussinesq-type equations are compared for the applications of these Boussinesq-type equations in coastal engineering with relatively large sea areas. Then for improving the properties of Boussinesq-type equations, a new set of fully nonlinear Boussinseq-type equations with modified representative velocity are derived, which can be used for better linear dispersion and nonlinearity. Based on the method of minimizing the overall error in different ranges of applications, sets of parameters are determined with optimized linear dispersion, linear shoaling and nonlinearity, respectively. Finally, a test example is given for validating the results of this study. Both results show that the equations with optimized parameters display better characteristics than the ones obtained by matching with pad6 approximation. 展开更多
关键词 Boussinesq-type equations linear dispersion shoaling gradient NONlinearITY
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Lyapunov-type Inequalities For A System of Nonlinear Difference Equations
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作者 WEI Geng-ping 《Chinese Quarterly Journal of Mathematics》 2019年第1期88-98,共11页
This paper establishes several new Lyapunov-type inequalities for the system of nonlinear difference equations■,which extend/supplement and improve some related existing ones.
关键词 Lyapunov-type inequality linear difference system Nonlinear difference system Hamiltonian difference system
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Adaptive Interval Type-2 Fuzzy Sliding Mode Control Based on Feedback Linearization
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作者 Jing Hua Yang Cai Yimin Li 《控制工程期刊(中英文版)》 2014年第5期138-149,共12页
关键词 模糊滑模控制 反馈线性化 自适应 模式控制 区间 非线性系统 模糊系统 模糊逻辑控制
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A TOBIN-TYPE ESTIMATE OF CENSORED LINEAR MODELS
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作者 陈希孺 朱力行 《Acta Mathematica Scientia》 SCIE CSCD 1998年第4期361-370,共10页
The paper presents a two-stage method for estimating the parameters in the censored linear model Y-i = max(0, alpha(o) + X-i'beta(o)), 1 less than or equal to i less than or equal to n. In the first stage the data... The paper presents a two-stage method for estimating the parameters in the censored linear model Y-i = max(0, alpha(o) + X-i'beta(o)), 1 less than or equal to i less than or equal to n. In the first stage the data are grouped in some groups and then some adjustments are made, the results are used in the latter stage to form a Tobin-type estimate. The asymptotic normality of the estimate is proved and some simulations are made. 展开更多
关键词 CENSORING linear models Tobin-type estimate
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Stechkin-Marchaud Type Inequalities in Lp for Linear Combination of Bernstein-Durrmeyer Operators
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作者 Feng Guo Meiqin Ke 《Open Journal of Applied Sciences》 2012年第4期228-232,共5页
In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we ob... In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we obtain the inverse result of approximation for linear combination of Bernstein-Durrmeyer operators with . Meanwhile we unify and extend some previous results. 展开更多
关键词 BERNSTEIN-DURRMEYER OPERATORS linear combination K-FUNCTIONAL Stechkin-Marchaud-type inequalities modulus of smoothness
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Bianchi Type-V Cosmological Model with Linear Equation of State in Brans-Dicke Theory of Gravitation
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作者 Sharad Kandalkar Seema Samdurkar 《International Journal of Astronomy and Astrophysics》 2014年第3期429-436,共8页
A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law re... A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law relation between scalar field &oslash;and scale factor R to find the solutions. Some physical and kinematical properties of the model are also discussed. 展开更多
关键词 Bianchi type-V Model BRANS-DICKE Theory linear Equation of State
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A matrix Padé-type-Routh model reduction method for multivariable linear systems
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作者 吴蓓蓓 顾传青 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期377-380,共4页
In the present paper, the formulae for matrix Padé-type approximation were improved. The mixed model reduction method of matrix Padé-type-Routh for the multivariable linear systems was presented. A well-know... In the present paper, the formulae for matrix Padé-type approximation were improved. The mixed model reduction method of matrix Padé-type-Routh for the multivariable linear systems was presented. A well-known example was given to illustrate that the mixed method is efficient. 展开更多
关键词 matrix Padé-type approximation(MPTA) Routh table model reduction multivariable linear systems
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Polynomial Complexity Bounds of Mehrotra-type Predictor-corrector Algorithms for Linear Programming over Symmetric Cones
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作者 刘长河 尚有林 李振国 《Chinese Quarterly Journal of Mathematics》 2015年第4期475-494,共20页
We establish polynomial complexity corrector algorithms for linear programming over bounds of the Mehrotra-type predictor- symmetric cones. We first slightly modify the maximum step size in the predictor step of the s... We establish polynomial complexity corrector algorithms for linear programming over bounds of the Mehrotra-type predictor- symmetric cones. We first slightly modify the maximum step size in the predictor step of the safeguard based Mehrotra-type algorithm for linear programming, that was proposed by Salahi et al. Then, using the machinery of Euclidean Jordan algebras, we extend the modified algorithm to symmetric cones. Based on the Nesterov-Todd direction, we obtain O(r log ε1) iteration complexity bound of this algorithm, where r is the rank of the Jordan algebras and ε is the required precision. We also present a new variant of Mehrotra-type algorithm using a new adaptive updating scheme of centering parameter and show that this algorithm enjoys the same order of complexity bound as the safeguard algorithm. We illustrate the numerical behaviour of the methods on some small examples. 展开更多
关键词 linear programming symmetric cone Euclidean Jordan algebra interior-point methods Mehrotra-type algorithm polynomial complexity
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Identification of Question and Non-Question Segments in Arabic Monologues Using Prosodic Features: Novel Type-2 Fuzzy Logic and Sensitivity-Based Linear Learning Approaches
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作者 Sunday Olusanya Olatunji Lahouari Cheded +1 位作者 Wasfi G. Al-Khatib Omair Khan 《Journal of Intelligent Learning Systems and Applications》 2013年第3期165-175,共11页
In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel c... In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel classification approaches to this problem: one based on the use of the powerful type-2 fuzzy logic systems (type-2 FLS) and the other on the use of the discriminative sensitivity-based linear learning method (SBLLM). The use of prosodic features has been used in a plethora of practical applications, including speech-related applications, such as speaker and word recognition, emotion and accent identification, topic and sentence segmentation, and text-to-speech applications. In this paper, we continue to specifically focus on the Arabic language, as other languages have received a lot of attention in this regard. Moreover, we aim to improve the performance of our previously-used techniques, of which the support vector machine (SVM) method was the best performing, by applying the two above-mentioned powerful classification approaches. The recorded continuous speech is first segmented into sentences using both energy and time duration parameters. The prosodic features are then extracted from each sentence and fed into each of the two proposed classifiers so as to classify each sentence as a Question or a Non-Question sentence. Our extensive simulation work, based on a moderately-sized database, showed the two proposed classifiers outperform SVM in all of the experiments carried out, with the type-2 FLS classifier consistently exhibiting the best performance, because of its ability to handle all forms of uncertainties. 展开更多
关键词 ARABIC Monologues Prosodic Features type-2 FUZZY LOGIC Systems Sensitivity Based linear LearningMethod Support Vector Machines
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两类Armijo-type线搜索下的PRP新算法 被引量:3
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作者 王开荣 曹伟 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第7期13-17,共5页
给出了新的PRP算法,该算法具有充分下降性和在无需任何线搜索的情况下自动保持搜索方向在可行域的特性,而且该算法在非凸函数和一致凸函数上具有全局收敛性,最后证明了新算法的线性收敛速度.
关键词 无约束最优化 共轭梯度法 Armijo-type线搜索 全局收敛性 R-线性收敛
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Dashnic-Zusmanovich type矩阵线性互补问题的误差界新研究
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作者 李艳艳 黄卫华 《湖北民族学院学报(自然科学版)》 CAS 2019年第3期274-276,共3页
研究Dashnic-Zusmanovich type矩阵A的线性互补问题的误差界估计问题,在已有A的元素的逆矩阵无穷范数估计式的基础上,给出A的线性互补问题的误差界.对于该问题的研究进一步完善了关于Dashnic-Zusmanovich type矩阵的相关研究.最后,用数... 研究Dashnic-Zusmanovich type矩阵A的线性互补问题的误差界估计问题,在已有A的元素的逆矩阵无穷范数估计式的基础上,给出A的线性互补问题的误差界.对于该问题的研究进一步完善了关于Dashnic-Zusmanovich type矩阵的相关研究.最后,用数值算例进行了补充说明. 展开更多
关键词 Dashnic-Zusmanovichtype矩阵 无穷范数 线性互补 误差界
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NONTRIVIAL SOLUTIONS FOR ASYMPTOTICALLY LINEAR HAMILTONIAN SYSTEMS WITH LAGRANGIAN BOUNDARY CONDITIONS 被引量:1
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作者 刘春根 张清业 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1545-1558,共14页
In this article, we study the existence of nontrivial solutions for a class of asymptotically linear Hamiltonian systems with Lagrangian boundary conditions by the Galerkin approximation methods and the L-index theory... In this article, we study the existence of nontrivial solutions for a class of asymptotically linear Hamiltonian systems with Lagrangian boundary conditions by the Galerkin approximation methods and the L-index theory developed by the first author. 展开更多
关键词 kLagrangian boundary conditions Hamiltonian systems asymptotically linear Maslov-type index
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Generation of a χ-type four-atom entangled state 被引量:1
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作者 沈洪武 王洪福 +1 位作者 计新 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3706-3709,共4页
This paper proposes a scheme to generate a new x-type four-atom entangled state for the first time by using linear optics elements, four one-sided cavities (one three-level atom) and a conventional photon detector. ... This paper proposes a scheme to generate a new x-type four-atom entangled state for the first time by using linear optics elements, four one-sided cavities (one three-level atom) and a conventional photon detector. The linear optical elements and conventional photon detector are simple and accessible in experiments, which makes the scheme more feasible with current technology. In addition, the state |X^00)3214 with probability 1 can be generated as long as there is no photon loss. 展开更多
关键词 quantum entanglement linear optics x-type entangled state
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ORTHOGONAL POLYNOMIALS AND DETERMINANT FORMULAS OF FUNCTION-VALUED PADE-TYPE APPROXIMATION USING FOR SOLUTION OF INTEGRAL EQUATIONS 被引量:2
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作者 顾传青 潘宝珍 吴蓓蓓 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第6期853-860,共8页
To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the s... To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the solution, this method can construct an approximate solution to solve the given integral equation. On the basis of the orthogonal polynomials, two useful determinant expressions of the numerator polynomial and the denominator polynomial for Padé-type approximation are explicitly given. 展开更多
关键词 generalized linear functional function-valued Padé-type approximation Fredholm integral equation orthogonal polynomial determinant formula
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A comparison of phantom linear scalar field and non-linear Born-Infeld scalar field
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作者 周建华 陆惠卿 +1 位作者 方伟 魏晨星 《Journal of Shanghai University(English Edition)》 CAS 2008年第5期405-409,共5页
This paper studies phantom linear scalar field (LSF) and phantom non-linear Born-Infeld (NLBI) scalar field with square potential of the form V(Ф) =1/2m^2Ф^2. The equation of state parameter w(z), and evolut... This paper studies phantom linear scalar field (LSF) and phantom non-linear Born-Infeld (NLBI) scalar field with square potential of the form V(Ф) =1/2m^2Ф^2. The equation of state parameter w(z), and evolution of scale factor a(t) in both phantom LSF and phantom NLBI scalar model are explored. The age of universe Hot and the transition redshift Z are obtained. The Gold data set of 157-SN-Ia is used to constrain parameters of the two models by numerical calculation. The phantom LSF is slightly better than the phantom NLBI type scalar field model for a large m. Although a smaller m corresponding to a slower rolling of field Ф better fits the observation data, the difference between phantom NLBI scalar field and phantom LSF is not distinct in this case. 展开更多
关键词 dark energy phantom non-linear Born-Infeld (NLBI) type scalar field phantom linear scalar field (LSF)
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GRADIENT ESTIMATES AND LIOUVILLE THEOREMS FOR LINEAR AND NONLINEAR PARABOLIC EQUATIONS ON RIEMANNIAN MANIFOLDS 被引量:1
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作者 朱晓宝 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期514-526,共13页
In this article, we will derive local elliptic type gradient estimates for positive solutions of linear parabolic equations (△-e/et)u(x,t)+q(x,t)u^p(x,t)=0 and nonlinear parabolic equations (△-e/et)u(x,... In this article, we will derive local elliptic type gradient estimates for positive solutions of linear parabolic equations (△-e/et)u(x,t)+q(x,t)u^p(x,t)=0 and nonlinear parabolic equations (△-e/et)u(x,t)+h(x,t)u^p(x,t)=0(p 〉 1) on Riemannian manifolds.As applications, we obtain some theorems of Liouville type for positive ancient solutions of such equations. Our results generalize that of Souplet-Zhang ([1], Bull. London Math. Soc. 38(2006), 1045-1053) and the author ([2], Nonlinear Anal. 74 (2011), 5141-5146). 展开更多
关键词 Gradient estimate linear parabolic equation nonlinear parabolic equation Liouville type theorem
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