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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method normalized solution
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High Energy Normalized Solutions for the Schrodinger Equations with Exponential Critical Growth
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作者 ZHANG Xiao-cang XULi-ping 《Chinese Quarterly Journal of Mathematics》 2025年第1期1-19,共19页
In this paper,we study high energy normalized solutions for the following Schr?dinger equation{-Δu+V(x)u+λu=f(u),in R^(2),∫_(R^(2))|u|^(2)dx=c,where c>0,λ∈R will appear as a Lagrange multiplier,V(x)=ω|x|2 rep... In this paper,we study high energy normalized solutions for the following Schr?dinger equation{-Δu+V(x)u+λu=f(u),in R^(2),∫_(R^(2))|u|^(2)dx=c,where c>0,λ∈R will appear as a Lagrange multiplier,V(x)=ω|x|2 represents a trapping potential,and f has an exponential critical growth.Under the appropriate assumptions of f,we have obtained the existence of normalized solutions to the above Schr?dinger equation by introducing a variational method.And these solutions are also high energy solutions with positive energy. 展开更多
关键词 High energy normalized solutions Schrodinger equation Trapping potential Exponential critical growth Variational method
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NORMALIZED SOLUTIONS FOR THE GENERAL KIRCHHOFF TYPE EQUATIONS
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作者 Wenmin LIU Xuexiu ZHONG Jinfang ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1886-1902,共17页
In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constrain... In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constraint f_(R)^N u^2dx=c,where M∈C([0,∞))is a given function satisfying some suitable assumptions.Our argument is not by the classical variational method,but by a global branch approach developed by Jeanjean et al.[J Math Pures Appl,2024,183:44–75]and a direct correspondence,so we can handle in a unified way the nonlinearities g(s),which are either mass subcritical,mass critical or mass supercritical. 展开更多
关键词 normalized solution Kirchhoff type equations general nonlinearities asymptotic behavior
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Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models
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作者 Jia-Hao Wang Rui Qiu +4 位作者 An-Kang Hu Ye-Qi Liu Zhen Wu Hui Zhang Jun-Li Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期42-59,共18页
The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female populat... The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was constructed.Considering backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel phantom.Image acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray spectra.We calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was investigated.The D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in China.The difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth direction.The results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT. 展开更多
关键词 Digital breast tomosynthesis normalized glandular dose coefficients Detailed breast model Monte Carlo simulation
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MULTIPLICITY OF NORMALIZED SOLUTIONS FOR THE FRACTIONAL SCHR?DINGER-POISSON SYSTEM WITH DOUBLY CRITICAL GROWTH
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作者 孟禹希 贺小明 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期997-1019,共23页
In this paper,we are concerned with solutions to the fractional Schrodinger-Poisson system■ with prescribed mass ∫_(R^(3))|u|^(2)dx=a^(2),where a> 0 is a prescribed number,μ> 0 is a paremeter,s ∈(0,1),2 <... In this paper,we are concerned with solutions to the fractional Schrodinger-Poisson system■ with prescribed mass ∫_(R^(3))|u|^(2)dx=a^(2),where a> 0 is a prescribed number,μ> 0 is a paremeter,s ∈(0,1),2 <q <2_(s)^(*),and 2_(s)^(*)=6/(3-2s) is the fractional critical Sobolev exponent.In the L2-subcritical case,we show the existence of multiple normalized solutions by using the genus theory and the truncation technique;in the L^(2)-supercritical case,we obtain a couple of normalized solutions by developing a fiber map.Under both cases,to recover the loss of compactness of the energy functional caused by the doubly critical growth,we need to adopt the concentration-compactness principle.Our results complement and improve upon some existing studies on the fractional Schrodinger-Poisson system with a nonlocal critical term. 展开更多
关键词 fractional Schrodinger-Poisson system normalized solutions variational methods L^(2)-subcritical L^(2)-supercritical
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Normalized Ground State Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan ZHAO Hui-yan XU Li-ping 《Chinese Quarterly Journal of Mathematics》 2024年第3期250-261,共12页
In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/... In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/N Under appropriate hypotheses on V(x),we prove that the above Choquard equation has a normalized ground state solution by utilizing variational methods. 展开更多
关键词 Choquard equation Nonconstant potential function normalized ground state solutions Variational methods
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用Normalized Cut法自动提取乳腺超声图像中的肿瘤边缘 被引量:3
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作者 苏燕妮 汪源源 《应用科学学报》 EI CAS CSCD 北大核心 2010年第6期601-608,共8页
提出一种带权重邻域灰度信息的normalized cut(Ncut)方法,该方法能够全自动提取乳腺超声图像的肿瘤边缘.通过Ncut分块乳腺超声图像中的各块灰度及空间分布特征来识别待检测肿瘤的轮廓.对于少数分割不精确的结果,可用结合局部能量项的动... 提出一种带权重邻域灰度信息的normalized cut(Ncut)方法,该方法能够全自动提取乳腺超声图像的肿瘤边缘.通过Ncut分块乳腺超声图像中的各块灰度及空间分布特征来识别待检测肿瘤的轮廓.对于少数分割不精确的结果,可用结合局部能量项的动态轮廓模型对所提取的初始边缘进行修正,使其更接近真实目标轮廓.对包含112幅乳腺肿瘤超声图像的数据库进行边缘提取,结果表明:该方法无需人工干预,能够准确有效地实现肿瘤分割,且计算量小,有望提高计算机辅助诊断的自动化程度. 展开更多
关键词 超声图像 乳腺肿瘤 边缘 自动提取 normalized CUT 局部调整
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International Normalized Ratio:青年脑梗死危险因素
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作者 张斌 高聪 《中国医药科学》 2011年第11期14-15,共2页
目的评估入院时国际标准化比值水平对青年脑梗死患者出院时短期预后的影响。方法分析585例患脑梗死的青年患者,这些患者从来未服用华法令。所有患者都在发病48h后入院,脑影像学检查(CT或者MRI)在入院后24~48h后进行。结果通过logistic... 目的评估入院时国际标准化比值水平对青年脑梗死患者出院时短期预后的影响。方法分析585例患脑梗死的青年患者,这些患者从来未服用华法令。所有患者都在发病48h后入院,脑影像学检查(CT或者MRI)在入院后24~48h后进行。结果通过logistic回归模型,笔者发现较高的INR和纤维蛋白原水平预示着患者在出院时有较差的预后。结论应用该回归分析模型,笔者确定INR是青年脑梗死患者临床预后的独立危险因素,因此入院时INR的水平不仅仅是凝血功能检测的指标,而且将为青年脑梗死患者提供一个实用的临床预后信息。 展开更多
关键词 INTERNATIONAL normalized RATIO 脑梗死 青年
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一种与图论Normalized Cut方法相结合的双阈值图像分割 被引量:2
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作者 朱欣欣 张大志 +1 位作者 田金文 张钧 《红外与激光工程》 EI CSCD 北大核心 2006年第z4期48-53,共6页
提出了一种与图论方法相结合的双阈值分割方法,先采用双阈值划分图像区域,然后建立无向图,采用 Normalized Cut 方法划分图,完成图像分割。本文的方法综合考虑了像素间的灰度值和空间距离的相似性,并且运算量比传统的图论方法要小很多... 提出了一种与图论方法相结合的双阈值分割方法,先采用双阈值划分图像区域,然后建立无向图,采用 Normalized Cut 方法划分图,完成图像分割。本文的方法综合考虑了像素间的灰度值和空间距离的相似性,并且运算量比传统的图论方法要小很多。实验结果表明,算法可以取得很好的分割效果。 展开更多
关键词 图论 normalized CUT 图像分割 双阈值
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基于形态学分水岭的Normalized Cut图像分割方法 被引量:2
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作者 刘贺鹏 吕建平 《电子科技》 2016年第9期12-14,共3页
针对传统分水岭分割后所产生的过分割问题,提出了一种基于形态学分水岭算法和Normalized Cut算法相结合的图像分割方法。在传统分水岭分割的基础上,融合形态学算法进行初步分割,并将分割后各个子区域的形心和平均灰度值作为Normalized ... 针对传统分水岭分割后所产生的过分割问题,提出了一种基于形态学分水岭算法和Normalized Cut算法相结合的图像分割方法。在传统分水岭分割的基础上,融合形态学算法进行初步分割,并将分割后各个子区域的形心和平均灰度值作为Normalized Cut算法的输入参数,完成图像分割。结果表明,组合算法既避免了过分割现象,也达到了Normalized Cut算法的分割精度,是一种有效的图像分割算法。 展开更多
关键词 图像分割 分水岭 形态学 normalized CUT
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Correspondence normalized ghost imaging on compressive sensing 被引量:2
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作者 赵生妹 庄鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期287-291,共5页
Ghost imaging (GI) offers great potential with respect to conventional imaging techniques. It is an open problem in GI systems that a long acquisition time is be required for reconstructing images with good visibili... Ghost imaging (GI) offers great potential with respect to conventional imaging techniques. It is an open problem in GI systems that a long acquisition time is be required for reconstructing images with good visibility and signal-to-noise ratios (SNRs). In this paper, we propose a new scheme to get good performance with a shorter construction time. We call it correspondence normalized ghost imaging based on compressive sensing (CCNGI). In the scheme, we enhance the signal-to-noise performance by normalizing the reference beam intensity to eliminate the noise caused by laser power fluctuations, and reduce the reconstruction time by using both compressive sensing (CS) and time-correspondence imaging (CI) techniques. It is shown that the qualities of the images have been improved and the reconstruction time has been reduced using CCNGI scheme. For the two-grayscale "double-slit" image, the mean square error (MSE) by GI and the normalized GI (NGI) schemes with the measurement number of 5000 are 0.237 and 0.164, respectively, and that is 0.021 by CCNGI scheme with 2500 measurements. For the eight-grayscale "lena" object, the peak signal-to-noise rates (PSNRs) are 10.506 and 13.098, respectively using G1 and NGI schemes while the value turns to 16.198 using CCNGI scheme. The results also show that a high-fidelity GI reconstruction has been achieved using only 44% of the number of measurements corresponding to the Nyquist limit for the two-grayscale "double-slit" object. The qualities of the reconstructed images using CCNGI are almost the same as those from GI via sparsity constraints (GISC) with a shorter reconstruction time. 展开更多
关键词 ghost imaging compressive sensing time-correspondence normalIZING
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Effect of normalized plasma frequency on electron phase-space orbits in a free-electron laser 被引量:2
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作者 吉驭嫔 王时建 +5 位作者 徐竟跃 徐勇根 刘晓旭 卢宏 黄小莉 张世昌 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期242-246,共5页
Irregular phase-space orbits of the electrons are harmful to the electron-beam transport quality and hence deteriorate the performance of a free-electron laser (FEL). In previous literature, it was demonstrated that... Irregular phase-space orbits of the electrons are harmful to the electron-beam transport quality and hence deteriorate the performance of a free-electron laser (FEL). In previous literature, it was demonstrated that the irregularity of the electron phase-space orbits could be caused in several ways, such as varying the wiggler amplitude and inducing sidebands. Based on a Hamiltonian model with a set of self-consistent differential equations, it is shown in this paper that the electron- beam normalized plasma frequency functions not only couple the electron motion with the FEL wave, which results in the evolution of the FEL wave field and a possible power saturation at a large beam current, but also cause the irregularity of the electron phase-space orbits when the normalized plasma frequency has a sufficiently large value, even if the initial energy of the electron is equal to the synchronous energy or the FEL wave does not reach power saturation. 展开更多
关键词 free-electron laser electron phase-space orbit normalized plasma frequency IRREGULARITY
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ON THE SHARP GROWTH,COVERING THEOREMS FOR NORMALIZED BIHOLOMORPHIC MAPPINGS IN C^n 被引量:2
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作者 刘小松 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期803-812,共10页
In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almos... In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almost starlike mappings of order α and starlike mappings of order α are established. Meanwhile, the construction of the above mappings on bounded starlike circular domain in Cn is also discussed, it provides the extremal mappings for the growth, covering theorems of the above mappings. 展开更多
关键词 Zero of order k 1 normalized biholomorphic mappings almost starlike mappings of order α starlike mappings of order α GROWTH covering theorems
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International normalized ratio as a predictor of mortality in trauma patients in India 被引量:1
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作者 Ankur Verma Tamorish Kole 《World Journal of Emergency Medicine》 CAS 2014年第3期192-195,共4页
BACKGROUND:Hemorrhage is the second leading cause of death in trauma patients preceded only by traumatic brain injury. But hemorrhagic shock is the most common cause of preventable death within 6 hours of admission. T... BACKGROUND:Hemorrhage is the second leading cause of death in trauma patients preceded only by traumatic brain injury. But hemorrhagic shock is the most common cause of preventable death within 6 hours of admission. Traumatic coagulopathy is a hypocoagulable state that occurs in the most severely injured. International normalized ratio(INR) and its relationship with trauma mortality have not been studied specifi cally. This study aimed to establish a predictive value of INR for trauma-related mortality.METHODS:A total of 99 trauma patients aged 18–70 years were included in the study. Their INR was determined and patient progression was followed up till death/discharge. According to previous retrospective studies,the cutoff value for INR in our study was kept at 1.5.RESULTS:The total mortality rate of the patients was 16.16%(16/99). The mean INR was 1.45 with a SD of 1.35. INR was deranged in a total of 14 patients(14.14%). Of these patients,11 died(78.57%) and 3 survived. INR was deranged in 11(68.75%) of the 16 patients who died,but 5 deaths(31.25%) had normal INR values. The sensitivity of INR was 69%(95%CI 41%–88%) and the specificity 96%(95%CI 90%–99%). The diagnostic accuracy of INR was 92%(95%CI 85%–96%). Positive predictive value and negative predictive value were 79%(95%CI 49%–95%) and 94%(95%CI 87%–98%),respectively.CONCLUSION:Our results showed that INR is a good predictor of mortality in trauma patients. 展开更多
关键词 HEMORRHAGE TRAUMA International normalized ratio MORTALITY
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THE EXISTENCE AND STABILITY OF NORMALIZED SOLUTIONS FOR A BI-HARMONIC NONLINEAR SCHR?DINGER EQUATION WITH MIXED DISPERSION 被引量:1
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作者 罗庭健 郑世骏 朱世辉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期539-563,共25页
In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bu... In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bulk medium with a second-order dispersion term.Denoting by Qpthe ground state for the BNLS withμ=0,we prove that in the mass-subcritical regime p∈(1,1+8/d),there exist orbit ally stable ground state solutions for the BNLS when p∈(-λ0,∞)for someλ0=λ0(p,d,‖Qp‖L2)>0.Moreover,in the mass-critical case p=1+8/d,we prove the orbital stability on a certain mass level below‖Q*‖L2,provided thatμ∈(-λ1,0),where■and Q*=Q1+8/d.The proofs are mainly based on the profile decomposition and a sharp Gagliardo-Nirenberg type inequality.Our treatment allows us to fill the gap concerning the existence of the ground states for the BNLS when p is negative and p∈(1,1+8/d]. 展开更多
关键词 elliptic equations bi-harmonic operator normalized solutions profile decomposition
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SOLUTIONS TO A CLASS OF PARABOLIC INHOMOGENEOUS NORMALIZED p-LAPLACE EQUATIONS
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作者 刘芳 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期477-494,共18页
In this article, we prove that viscosity solutions of the parabolic inhomogeneous equationsn+p/put-△p^Nu=f(x,t)can be characterized using asymptotic mean value properties for all p ≥ 1, including p = 1 and p = ∞... In this article, we prove that viscosity solutions of the parabolic inhomogeneous equationsn+p/put-△p^Nu=f(x,t)can be characterized using asymptotic mean value properties for all p ≥ 1, including p = 1 and p = ∞. We also obtain a comparison principle for the non-negative or non-positive inhomogeneous term f for the corresponding initial-boundary value problem and this in turn implies the uniqueness of solutions to such a problem. 展开更多
关键词 Parabolic normalized p-Laplace equation viscosity solution asymptotic mean value property comparison principle uniqueness theorem infinity Laplacian
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The Normalized Analysis of a Surface Heterogeneous Reaction of a Propane/Air Mixture into a Micro-Channel
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作者 A.Fanaee J.A.Esfahani 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第12期132-136,共5页
The effect of catalytic surface reaction on non-reactive flow in micro-channels is investigated.The hydraulic diameter of the channel is considered within the range of 0.2-1.2 mm,and the channel length is considered t... The effect of catalytic surface reaction on non-reactive flow in micro-channels is investigated.The hydraulic diameter of the channel is considered within the range of 0.2-1.2 mm,and the channel length is considered to be 5 mm.The whole length of the channel wall is coated with a catalyst.The sensitivity analysis shows that the effect of normalized hydraulic diameter is more than the normalized longitude coordinates in accordance with the existence of the large ratio of surface area to volume in the micro-channel.For validation of this model,the variation of fuel conversion is compared with the published experimental data and shows an acceptable agreement. 展开更多
关键词 catalyst. normalized COORDINATES
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THE EXISTENCE OF GROUND STATE NORMALIZED SOLUTIONS FOR CHERN-SIMONS-SCHRODINGER SYSTEMS
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作者 毛宇 吴行平 唐春雷 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2649-2661,共13页
In this paper,we study normalized solutions of the Chern-Simons-Schrödinger system with general nonlinearity and a potential in H^(1)(ℝ^(2)).When the nonlinearity satisfies some general 3-superlinear conditions,w... In this paper,we study normalized solutions of the Chern-Simons-Schrödinger system with general nonlinearity and a potential in H^(1)(ℝ^(2)).When the nonlinearity satisfies some general 3-superlinear conditions,we obtain the existence of ground state normalized solutions by using the minimax procedure proposed by Jeanjean in[L.Jeanjean,Existence of solutions with prescribed norm for semilinear elliptic equations,Nonlinear Anal.(1997)]. 展开更多
关键词 Chern-Simons-Schrodinger system non-constant potential Pohozaev identity ground state normalized solution
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An Upper Bound for the Number of Normalized Latin Square
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作者 DUAN Lian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期585-589,共5页
In this note, the author find an upper bound formula for the number of the p × p normalized Latin Square,the first row and column of which are both standard order 1, 2,…p.
关键词 Latin square normalized latin square inclusion-exclusion principe
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Computation and parameterization of normalized glandular dose using Geant4 被引量:1
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作者 Omrane Kadri Mohammed Ali Alnafea Khaled Shamma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第3期51-56,共6页
The average absorbed dose in glandular tissue is the most appropriate parameter for the assessment of the radiation-induced risk during breast imaging. The aims of this work concern:(1) the investigation of the variat... The average absorbed dose in glandular tissue is the most appropriate parameter for the assessment of the radiation-induced risk during breast imaging. The aims of this work concern:(1) the investigation of the variation effect of any related update to photon cross-section data-bases on the computation of the normalized glandular dose(Dg N) for mammography quality control tests and(2) the proposition of a parameterization method leading to provide Dg N values function of the breast thickness(T) and the particle energy(E) instead of E alone, as normally known. We analyzed the change effect of the photon cross-section data-bases on the computation of Dg N. Those coefficients, generated using the Geant4 Monte Carlo toolkit, were studied over a range of compressed breast thickness of 2–8 cm for monoenergetic(1–120 ke V by 1 ke V intervals) and polyenergetic(23–35 k Vp by 2 k Vp intervals) X-ray beams. Moreover, breast tissue composition ranging from about0% glandular(about 100% adipose) to 100% glandular(0% adipose) was also covered. The successful parameterization of Dg N look-up table function of the breast thickness and energy, will compact its analytical form without loss of accuracy. All parameterization fits resulted in r2 values of 0.999 or better. 展开更多
关键词 GEANT4 剂量计算 吸收剂量 参数化 归一化 腺体 质量控制 X线摄影
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