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Clinical Application of Sex Hormone in Different Physiological Periods in the Diagnosis of Infertility Patients
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作者 Jianhong Nong Daxian Tan +4 位作者 Arshad Mehmood Tingchao Wang Xin Liu Li Deng Bowen Wei 《Natural Science》 2024年第6期102-110,共9页
Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different ... Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different physiological periods in the diagnosis of infertility patients. Methods: From December 2019 to May 2021, a total of 93 infertility patients were admitted and selected as the observation group. Among them, 31 cases were in the follicular stage, 31 cases in the ovulation stage, and 31 cases in the luteal stage. Ninety-three healthy women for fertility evaluation due to male infertility were selected as the control group. The control group included 31 women in the follicular phase, 31 women in the ovulatory phase, and 31 women in the luteal phase. The levels of sex hormones (prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), testosterone (T), and progesterone (P)) during different physiological phases were compared between the observation and control groups. Results: The follicular phase showed no significant difference in LH levels between the observation group and the control group. The observation group showed higher levels of PRL and P compared to the control group, while the levels of FSH, E2, and T were lower in the observation group compared to the control group. The ovulation phase showed no significant difference in PRL levels between the two groups. The observation group showed lower levels of LH, FSH, E2, T, and P compared to the control group. The luteal phase showed no statistical difference in E2 levels between the two groups. The observation group showed higher levels of PRL, LH, and FSH compared to the control group, while the levels of T and P were lower in the observation group compared to the control group. Conclusion: Infertile women show variations in hormone levels compared to the normal levels during the follicular phase, ovulatory phase, and luteal phase. 展开更多
关键词 different periods Sex Hormone Level Detection INFERTILITY Auxiliary Diagnosis
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Existence of Many and Infinitely Many Periodic Solutions for Some Types of Differential Delay Equations
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作者 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1993年第1期5-14,共10页
J.Kaplan and J.Yorke's method is extended to establish the exis- tence of many and infinitely many periodic solutions for the DDEs (t) =±f(x(t-1))±f(x(t-2))and (t)=±f(x(t-1).
关键词 difference differential equation periodic solution SYMMETRY
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A CONSERVATIVE DIFFERENCE SCHEME FOR CONSERVATIVE DIFFERENTIAL EQUATION WITH PERIODIC BOUNDARY 被引量:3
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作者 CAI Xin(蔡新) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1210-1215,共6页
The conservative form and singular perturbed ordinary differential equation with periodic boundary value problem were studied, and a conservative difference scheme was constructed. Using the method of decomposing the ... The conservative form and singular perturbed ordinary differential equation with periodic boundary value problem were studied, and a conservative difference scheme was constructed. Using the method of decomposing the singular term from its solution and combining an asymptotic expansion of the equation, it is proved that the scheme converges uniformly to the solution of differential equation with order one. 展开更多
关键词 conservative equation singular perturbation periodic boundary conservative difference scheme uniform convergence
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A CONSERVATIVE DIFFERENCE SCHEME FOR CONSERVATIVE DIFFERENTIAL EQUATION WITH PERIODIC BOUNDARY 被引量:4
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作者 蔡新 《应用数学和力学》 EI CSCD 北大核心 2001年第10期1092-1096,共5页
The conservative form and singular perturbed ordinary differential equation with periodic boundary value problem were studied, and a conservative difference scheme was constructed. Using the method of decomposing the ... The conservative form and singular perturbed ordinary differential equation with periodic boundary value problem were studied, and a conservative difference scheme was constructed. Using the method of decomposing the singular term from its solution and combining an asymptotic expansion of the equation, it is proved that the scheme converges uniformly to the solution of differential equation with order one. 展开更多
关键词 守恒方程 奇摄动 周期边界 一致收敛 差分格式 常微分方程 周期边值问题
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A SINGULAR PERTURBATION PROBLEM FOR PERIODIC BOUNDARY PARTIAL DIFFERENTIAL EQUATION
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作者 林鹏程 江本铦 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第3期281-290,共10页
In this paper, we consider a singular perturbation elliptic-parabolic partial differential equation for periodic boundary value problem, and construct a difference scheme. Using the method of decomposing the singular ... In this paper, we consider a singular perturbation elliptic-parabolic partial differential equation for periodic boundary value problem, and construct a difference scheme. Using the method of decomposing the singular term from its solution and combining an asymptotic expansion of the equation, we prove that the scheme constructed by this paper converges uniformly to the solution of its original problem with O(r+h2). 展开更多
关键词 elliptic-parabolic partial differential equation singular perturbation problem periodic boundary difference scheme uniform convergence
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Different optical properties in different periodic slot cavity geometrical morphologies
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作者 周静 沈萌 +3 位作者 杜澜 邓彩松 倪海彬 王鸣 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期500-506,共7页
In this paper,optical properties of two-dimensional periodic annular slot cavity arrays in hexagonal close-packing on a silica substrate are theoretically characterized by finite difference time domain(FDTD) simulat... In this paper,optical properties of two-dimensional periodic annular slot cavity arrays in hexagonal close-packing on a silica substrate are theoretically characterized by finite difference time domain(FDTD) simulation method.By simulating reflectance spectra,electric field distribution,and charge distribution,we confirm that multiple cylindrical surface plasmon resonances can be excited in annular inclined slot cavities by linearly polarized light,in which the four reflectance dips are attributed to Fabry–Perot cavity resonances in the coaxial cavity.A coaxial waveguide mode TE11 will exist in these annular cavities,and the wavelengths of these reflectance dips are effectively tailored by changing the geometrical pattern of slot cavity and the dielectric materials filled in the cavities.These resonant wavelengths are localized in annular cavities with large electric field enhancement and dissipate gradually due to metal loss.The formation of an absorption peak can be explained from the aspect of phase matching conditions.We observed that the proposed structure can be tuned over the broad spectral range of 600–4000 nm by changing the outer and inner radii of the annular gaps,gap surface topography.Meanwhile,different lengths of the cavity may cause the shift of resonance dips.Also,we study the field enhancement at different vertical locations of the slit.In addition,dielectric materials filling in the annular gaps will result in a shift of the resonance wavelengths,which make the annular cavities good candidates for refractive index sensors.The refractive index sensitivity of annular cavities can also be tuned by the geometry size and the media around the cavity.Annular cavities with novel applications can be implied as surface enhanced Raman spectra substrates,refractive index sensors,nano-lasers,and optical trappers. 展开更多
关键词 cylindrical surface plasmons finite difference time domain Fabry–Perot cavity resonances twodimensional periodical structure
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A review of the differences between musical genres and performing skills in different periods
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作者 ShuhuiJiang 《International Journal of Technology Management》 2017年第5期47-49,共3页
Playing skill is the basic condition of musical instrument performance, and its level directly influences the timbre and musical expression of the work. In order to make music more appealing, it is essential to improv... Playing skill is the basic condition of musical instrument performance, and its level directly influences the timbre and musical expression of the work. In order to make music more appealing, it is essential to improve performance skills. Only by mastering the flute playing skills skillfully, can the work be more vocal, the timbre is soft, and the timbre is more unified, so that the thoughts, feelings and profound connotations of the musical works are more deeply rooted. The generality of music genre, that is to say, can fully show the common principles of music creation in a period of music and the criterion of musical aesthetics. The individuality of the music genre fully demonstrates the individual characteristics of the composer. In the music works in different periods of the musicians, the specific performance we can see the typical character of a music period, different features also can feel different with the composer. 展开更多
关键词 different periods music genres performance skills differENCES research review
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Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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作者 梁廷波 《外科研究与新技术》 2003年第2期129-130,共2页
Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to M... Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to March 2002 were analyzed retrospectively. Three periods were defined objectively as period Ⅰ(1993-1997),Ⅱ(1999) and Ⅲ(2000 -2002). Operative techniques, recipients, original diseases, complications and survival rates were compared among the three periods. Results Malignant liver lesions were the main cause for liver transplantation in period Ⅰ and Ⅱ. The ratio of number of malignant disease to total recipients decreased gradually from period Ⅰ to Ⅱ (100%, 53% and 35%, respectively). The 1-year survival rate in patients with benign liver disease was 85 % and the total operative mortality was 5% in period Ⅲ. The incidence of hepatitis B virus reactivation or reinfection was 24% twelve months after liver transplantation. Vascular complication decreased but biliary complications did 展开更多
关键词 of Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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Existence of asymptotically almost periodic solutions and stability properties for functional difference equations 被引量:4
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作者 吴中华 《Journal of Chongqing University》 CAS 2012年第2期97-102,共6页
For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain li... For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain limiting equation. 展开更多
关键词 functional difference equations asymptotically almost periodic solutions total stability properties
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Existence of Three Positive Periodic Solutions of Neutral Nonlinear Functional Difference Equations 被引量:1
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作者 LIU Xing-yuan 《Chinese Quarterly Journal of Mathematics》 2015年第2期172-183,共12页
This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of... This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of at least three positive T-periodic solutions are established by using a fixed point theorem due to Avery and Peterson. 展开更多
关键词 positive periodic solution functional difference equation fixed-point theorem
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Two Positive Periodic Solutions of Delay Functional Difference System with Feedback Control 被引量:1
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作者 GUO Peng-fei ZHU Xian-yang LI Yong-kun 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期102-107,共6页
By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x(n)=-b(n)x(n)+f... By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x(n)=-b(n)x(n)+f(n,x(n-τ1(n)),…,x(n-τm(n)),u(n-δ(n))),△u(n)=-η(n)u(n)+a(n)x(n-σ(n)),n∈Z. 展开更多
关键词 delay difference system positive periodic solution feedback control fixed pointtheorem
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Effects of Different Sowing Dates on Weed Suppression and Pesticide Residue in Soil
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作者 刘统高 谢应忠 《Agricultural Science & Technology》 CAS 2016年第3期650-654,661,共6页
[Objective] To effectively suppress weeds and degrade pesticide residues in soil, pollution-free agricultural production is a very important way. [Method] In regions where high residual pesticides had been applied for... [Objective] To effectively suppress weeds and degrade pesticide residues in soil, pollution-free agricultural production is a very important way. [Method] In regions where high residual pesticides had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, early shallow ploughing and sowing later in the next spring, and late ploughing and sowing were conducted,and the effects of the three measures on weed suppression and reduction of pesticide residue in soil were analyzed by measuring the length and fresh weight of crop radicles. [Result] Trifluralin applied in the A. membranaceus field for a long term limited the growth of the alfalfa seedlings. That is, the radicle length of each plant was 2.1-2.9 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.19-0.20 g. Metsulfuron methyl applied in the alfalfa field for a long term also limited the growth of the alfalfa seedlings, that is, the radicle length of each plant was 1.9-2.0 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.13-0.15 g. Shallow ploughing was conducted within two days after the autumn harvest, and all weed seeds on the ground were plowed into the plough layer 0-10 cm instead of deep soil. Early shallow ploughing in the next spring could make most seeds of weeds in surface soil sprout early, and sowing was conducted after 10 d, so that about 40% of weeds sprouting early were killed off. However, after shallow ploughing and sowing were conducted 10 d later than the normal sowing period, and around 30% of weeds were killed off. In addition,the weeds left in soil should be removed manually at the seedling stage or in late period. These measures had no adverse impact on the growth and development of crop radicles and yield. [Conclusion] In regions where pesticides with long-term residue had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, different farming and sowing measures and artificia weeding could suppress weeds in the crop fields effectively, did not pollute soil environment, and promoted the degradation of pesticides left in soil. 展开更多
关键词 different farming periods WEED SUPPRESSION Pesticide residue in soil
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A meshless scheme for partial differential equations based on multiquadric trigonometric B-spline quasi-interpolation
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作者 高文武 王志刚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期152-156,共5页
Based on the multiquadric trigonometric B-spline quasi-interpolant, this paper proposes a meshless scheme for some partial differential equations whose solutions are periodic with respect to the spatial variable. This... Based on the multiquadric trigonometric B-spline quasi-interpolant, this paper proposes a meshless scheme for some partial differential equations whose solutions are periodic with respect to the spatial variable. This scheme takes into ac- count the periodicity of the analytic solution by using derivatives of a periodic quasi-interpolant (multiquadric trigonometric B-spline quasi-interpolant) to approximate the spatial derivatives of the equations. Thus, it overcomes the difficulties of the previous schemes based on quasi-interpolation (requiring some additional boundary conditions and yielding unwanted high-order discontinuous points at the boundaries in the spatial domain). Moreover, the scheme also overcomes the dif- ficulty of the meshless collocation methods (i.e., yielding a notorious ill-conditioned linear system of equations for large collocation points). The numerical examples that are presented at the end of the paper show that the scheme provides excellent approximations to the analytic solutions. 展开更多
关键词 QUASI-INTERPOLATION meshless collocation periodICITY divided difference
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Interdecadal Variations of Phase Delays Between Two Nino Indices at Different Time Scales
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作者 卞建春 杨培才 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期122-125,共4页
Phase delays between two Nino indices-sea surface temperatures in Nino regions 1+2 and 3.4 (1950-2001)-at different time scales are detected by wavelet analysis. Analysis results show that there are two types of perio... Phase delays between two Nino indices-sea surface temperatures in Nino regions 1+2 and 3.4 (1950-2001)-at different time scales are detected by wavelet analysis. Analysis results show that there are two types of period bifurcations in the Nino indices and that period bifurcation points exist only in the region where the wavelet power is small. Interdecadal variation features of phase delays between the two indices vary with different time scales. In the periods of 40-72 months, the phase delay changes its sign in 1977: Nino 1+2 indices are 2-4 months earlier than Nino 3.4 indices before 1977, but 3-6 months later afterwards. In the periods of 20-40 months, however, the phase delay changes its sign in another way: Nino 1+2 indices are 1-4 months earlier before 1980 and during 1986-90, but 1-4 months later during 1980-83 and 1993-2001. 展开更多
关键词 period bifurcations different time scales phase delay interdecadal variation
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Difference scattering field properties between periodic defect particles and three-dimensional slightly rough optical surface
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作者 葛城显 吴振森 +1 位作者 白靖 巩蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期140-147,共8页
Based on the practical situation of nondestructive examination, the calculation model of the composite scattering is established by using a three-dimensional half-space finite difference time domain, and the Monte Car... Based on the practical situation of nondestructive examination, the calculation model of the composite scattering is established by using a three-dimensional half-space finite difference time domain, and the Monte Carlo method is used to solve the problem of the optical surface with roughness in the proposed scheme. Moreover, the defect particles are observed as periodic particles for a more complex situation. In order to obtain the scattering contribution of defects inside the optical surface, a difference radar cross section is added into the model to analyze the selected calculations on the effects of numbers, separation distances, different depths and different materials of defects. The effects of different incident angles are also discussed. The numerical results are analyzed in detail to demonstrate the best position to find the defects in the optical surface by detecting in steps of a fixed degree for the incident angle. 展开更多
关键词 light scattering difference scattering field periodic particles rough optical surface
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EXISTENCE OF PERIODIC SOLUTIONS OF SYSTEM OF DIFFERENCE EQUATIONS
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作者 Wei Gengping Shen Jianhua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期320-326,共7页
This paper studies the nonautonomous nonlinear system of difference equations △x(n) A(n)x(n) + f(n,x(n)), n∈Z ,(*)where x(n)∈R^N,A(n) = (aij(n))N×N is an N×N matrix, with aij∈C(R,R... This paper studies the nonautonomous nonlinear system of difference equations △x(n) A(n)x(n) + f(n,x(n)), n∈Z ,(*)where x(n)∈R^N,A(n) = (aij(n))N×N is an N×N matrix, with aij∈C(R,R) for i,j = 1,2,3 ,N, and f = (f1,f2,... ,fN)^T ∈C(R×R^N,R^N), satisfying A(t+) = A(t), f(t+ω,z) = f(t, z) for any t∈R, (t, z) ∈R× RN and ∈is a positive integer. Sufficient conditions for the existence of ω-periodic solutions to equations (*) are obtained. 展开更多
关键词 systems of difference equations periodic solutions existence.
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Multiple Periodic Solutions for a Class of Fourth-order Difference Systems
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作者 张申贵 《Chinese Quarterly Journal of Mathematics》 2016年第3期260-268,共9页
By using critical point theory,we study periodic solutions for a class of fourthorder difference systems with partially periodic potential and linear nonlinearity.Some sufficient conditions for the existence of multip... By using critical point theory,we study periodic solutions for a class of fourthorder difference systems with partially periodic potential and linear nonlinearity.Some sufficient conditions for the existence of multiplicity of periodic solutions are obtained via generalized saddle point theorem. 展开更多
关键词 periodic solutions fourth-order difference system critical point
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Discrete Pseudo Almost Periodic Solutions for Some Difference Equations
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作者 Elhadi Ait Dads Khalil Ezzinbi Lahcen Lhachimi 《Advances in Pure Mathematics》 2011年第4期118-127,共10页
In this work, we study the existence and uniqueness of pseudo almost periodic solutions for some difference equations. Firstly, we investigate the spectrum of the shift operator on the space of pseudo almost periodic ... In this work, we study the existence and uniqueness of pseudo almost periodic solutions for some difference equations. Firstly, we investigate the spectrum of the shift operator on the space of pseudo almost periodic sequences to show the main results of this work. For the illustration, some applications are provided for a second order differential equation with piecewise constant arguments. 展开更多
关键词 difference EQUATIONS PSEUDO ALMOST periodic SEQUENCES Schift OPERATOR
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Existence of Positive Periodic Solutions for the Predator-Prey Difference System with Beddington-DeAngelis Functional Response and Time Delays
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作者 王烈 陈斯养 《Journal of Southwest Jiaotong University(English Edition)》 2010年第3期260-270,共11页
A nonautonomous predator-prey difference model with Beddington-DeAngelis functional response, diffusion, and time delays is investigated. The model consists of n competing preys and one predator, and the predator and ... A nonautonomous predator-prey difference model with Beddington-DeAngelis functional response, diffusion, and time delays is investigated. The model consists of n competing preys and one predator, and the predator and one prey are confined to one patch. First, eon^pts and results concerning the continuation theorem of coincidence degree are summarized. Then, a system of algebraic equations is proved to have a unique solution. Finally, the sufficient conditions for the existence of a difference system are established. The result is substantiated through numerical simulation. 展开更多
关键词 Predator-prey system Positive periodic solution difference equation
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Positive periodic solutions of higher-dimensional nonlinear functional difference equations
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作者 DAI Bin-xiang ZOU Jie-zhong ZHANG Na 《Journal of Central South University of Technology》 2005年第z1期274-277,共4页
In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the f... In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the form:x(n+ 1) =A(n)x(n) +λh(n)f(x(n- τ(n))), n∈ Z. 展开更多
关键词 positive periodic solution difference EQUATIONS CONE fixed point THEOREM
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