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Research on a bifurcation location algorithm of a drainage tube based on 3D medical images
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作者 Qiuling Pan Wei Zhu +2 位作者 Xiaolin Zhang Jincai Chang Jianzhong Cui 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期7-17,共11页
Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of iden... Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of identifying puncture points,a point-cloud search arithmetic method for modified adaptive weighted particle swarm optimization is proposed and used for optimal external axis extraction.According to the characteristics of the multitube drainage tube and the clinical needs of puncture for intracranial hematoma removal,the proposed algorithm can provide an optimal route for a drainage tube for the hematoma,the precise position of the puncture point,and preoperative planning information,which have considerable instructional significance for clinicians. 展开更多
关键词 Multitube drainage tube bifurcation localization algorithm 3D medical image Path planning Intracranial hematoma
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Fourier Power Spectrum Analysis of Exons for the Period-3 Behavior
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作者 YuanXinTIAN ChaoCHEN +3 位作者 XiaoYongZOU JianDingQIU PeiXiangCAI JinYuanMO 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第7期939-942,共4页
The period-3 behaviors of 105 exons from 20 genes in human were studied by Fourier power spectrum. The results indicated that not all exons show the period-3 behavior. The exons were adjusted in order to make them acc... The period-3 behaviors of 105 exons from 20 genes in human were studied by Fourier power spectrum. The results indicated that not all exons show the period-3 behavior. The exons were adjusted in order to make them accord with the order of the protein translated, and we found that the period-3 character is relation to the length of exons and the bases distribution in the three codon position. Furthermore, as long as the exons with period-3 behavior accord with the order of protein translated, they would exhibit the synonymous codons usage preference, and the codons with g/c at the third position are used in higher frequency. The results are significant to the gene prediction and the research on the introns. 展开更多
关键词 period-3 behavior Fourier power spectrum exons.
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甲状腺乳头状癌组织中SETDB2、Gal-3、PLEKHS1的表达情况及其对患者预后的预测价值
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作者 桑妙玉 杨小洁 +4 位作者 王志慧 张超 刘晓霞 周玲玲 白宝琴 《广西医学》 CAS 2023年第21期2545-2550,共6页
目的分析SET结构域分叉组蛋白赖氨酸甲基转移酶2(SETDB2)、半乳糖凝集素3(Gal-3)、pleckstrin同源结构域S1(PLEKHS1)在甲状腺乳头状癌组织中的表达情况,以及三者对患者预后的预测价值。方法(1)选择118例甲状腺乳头状癌患者作为研究组,4... 目的分析SET结构域分叉组蛋白赖氨酸甲基转移酶2(SETDB2)、半乳糖凝集素3(Gal-3)、pleckstrin同源结构域S1(PLEKHS1)在甲状腺乳头状癌组织中的表达情况,以及三者对患者预后的预测价值。方法(1)选择118例甲状腺乳头状癌患者作为研究组,45例甲状腺良性结节患者作为对照组。采用免疫组化法检测甲状腺乳头状癌组织和甲状腺良性结节组织中SETDB2、Gal-3、PLEKHS1蛋白表达情况。比较研究组与对照组之间,以及不同特征甲状腺乳头状癌患者之间病灶组织中SETDB2、Gal-3、PLEKHS1蛋白的阳性表达率。(2)随访1年,记录甲状腺乳头状癌患者的生存情况。分析SETDB2、Gal-3、PLEKHS1蛋白阳性表达和阴性表达患者的生存率;比较预后良好和预后不良患者SETDB2、Gal-3、PLEKHS1蛋白的阳性表达率。采用受试者工作特征(ROC)曲线分析SETDB2、Gal-3、PLEKHS1对甲状腺乳头状癌患者预后的预测价值。结果(1)与对照组相比,研究组病灶组织中SETDB2蛋白阳性表达率较低,Gal-3、PLEKHS1蛋白阳性表达率较高(P<0.05)。在甲状腺乳头状癌患者中,Ⅲ~Ⅳ期、浸润深度≥1/2、组织中低分化、淋巴结转移、肿瘤直径>1 cm的患者病灶组织中SETDB2蛋白阳性表达率更低,Gal-3、PLEKHS1蛋白阳性表达率更高(P<0.05)。(2)在甲状腺乳头状癌患者中,SETDB2蛋白阳性表达患者生存率高于SETDB2蛋白阴性表达患者,Gal-3、PLEKHS1蛋白阳性表达患者生存率低于Gal-3、PLEKHS1蛋白阴性表达患者(P<0.05);预后良好患者的SETDB2蛋白阳性表达率高于预后不良患者,Gal-3、PLEKHS1蛋白阳性表达率低于预后不良患者(P<0.05)。ROC曲线分析结果显示,SETDB2、Gal-3、PLEKHS1蛋白总评分预测甲状腺乳头状癌患者预后不良的曲线下面积分别为0.826、0.841、0.859。结论在甲状腺乳头状癌中,SETDB2呈低表达,而Gal-3、PLEKHS1呈高表达,三者均与患者的病情严重程度相关,且对预后具有一定的预测价值。 展开更多
关键词 甲状腺乳头状癌 SET结构域分叉组蛋白赖氨酸甲基转移酶2 半乳糖凝集素3 pleckstrin同源结构域S1 预后 预测价值
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Existence of Two Limit Cycles in Zeeman’s Class 30 for 3D Lotka-Volterra Competitive System
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作者 Yaoqi Li 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1584-1590,共7页
Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which ... Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which is generated by the Hopf bifurcation and the other is obtained by the Poincaré-Bendixson theorem.Yu et al.(J Math Anal Appl 436:521–555,2016,Sect.3.4)recalculated the first Liapunov coefficient of Gyllenberg and Yan’s system to be positive,rather than negative as in Gyllenberg and Yan(2009),and pointed out that the Poincaré-Bendixson theorem is not applicable for that system.Jiang et al.(J Differ Equ 284:183–218,2021,p.213)proposed an open question:“whether Zeeman’s class 30 can be rigorously proved to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem?”This paper provides four systems in Zeeman’s class 30 to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem and gives an answer to the above question. 展开更多
关键词 3-dimensional Lotka-Volterra(3D LV)competitive system Zeeman’s class 30 Fine focus Hopf bifurcation Poincaré-Bendixson theorem Limit cycle
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夹层椭圆形板的1/3亚谐解 被引量:8
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作者 李银山 张年梅 杨桂通 《应用数学和力学》 EI CSCD 北大核心 2003年第10期1017-1026,共10页
 研究了夹层椭圆形板的非线性强迫振动问题· 在以5个位移分量表示的夹层椭圆板的运动方程的基础上,导出了相应的非线性动力方程· 提出一类强非线性动力系统的叠加_叠代谐波平衡法· 将描述动力系统的二阶常微分方程...  研究了夹层椭圆形板的非线性强迫振动问题· 在以5个位移分量表示的夹层椭圆板的运动方程的基础上,导出了相应的非线性动力方程· 提出一类强非线性动力系统的叠加_叠代谐波平衡法· 将描述动力系统的二阶常微分方程,化为基本解为未知函数的基本微分方程和派生解为未知函数的增量微分方程· 通过叠加_叠代谐波平衡法得出了椭圆板的1/3亚谐解· 同时。 展开更多
关键词 夹层椭圆形板 叠加-叠代谐波平衡法 1/3亚谐解 分岔
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轴向移动局部浸液单向板的1:3内共振分析 被引量:3
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作者 李红影 郭星辉 +3 位作者 王延庆 李健 谢里阳 陈波 《力学学报》 EI CSCD 北大核心 2012年第3期643-647,共5页
考虑单向板的轴向速度、轴向张力、流固耦合作用以及阻尼等因素,基于由von Karman薄板大挠度方程得到的轴向移动局部浸液单向板的非线性振动方程,研究了外激励作用下单向板在1:3内共振情况时的非线性振动特性.首先利用Galerkin法对非线... 考虑单向板的轴向速度、轴向张力、流固耦合作用以及阻尼等因素,基于由von Karman薄板大挠度方程得到的轴向移动局部浸液单向板的非线性振动方程,研究了外激励作用下单向板在1:3内共振情况时的非线性振动特性.首先利用Galerkin法对非线性振动方程离散化,然后分别应用数值法和近似解析法对离散后模态方程组进行求解,获得了系统内共振情况下复杂的幅频特性曲线,并讨论了周期解的稳定性.最后研究了1:3内共振系统平均方程组的运动分岔现象. 展开更多
关键词 局部浸液单向板 非线性 轴向移动 1内共振 分岔
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非线性动力系统的规范形和余维3退化分叉 被引量:4
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作者 张伟 《力学学报》 EI CSCD 北大核心 1993年第5期548-559,共12页
本文里我们利用矩阵表示法计算了具有Z_(2^-)对称性时非线性动力系统的高阶规范形,求出了余维2退化和余维3退化情况下相应规范形的普适开折。最后利用所得到的规范形和普适开折讨论了非线性动力系统的余维3退化分叉。
关键词 高阶规范形 非线性 动力系统
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一类余维二向量场3-D解的存在性分析
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作者 邹勇 路淼 毕勤胜 《江苏大学学报(自然科学版)》 EI CAS 2003年第5期88-90,共3页
分析了一类余维二向量场的分岔过程 首先基于系统的规范型,得到了不同的定常解,然后针对不同的分岔解运用稳定性判据,分别确定其稳定性条件,在参数平面上定义了临界曲线 于是就将参数空间划分为不同的区域,不同的区域和不同的分岔解相对... 分析了一类余维二向量场的分岔过程 首先基于系统的规范型,得到了不同的定常解,然后针对不同的分岔解运用稳定性判据,分别确定其稳定性条件,在参数平面上定义了临界曲线 于是就将参数空间划分为不同的区域,不同的区域和不同的分岔解相对应,由此给出了该系统3 D解存在的必要条件及证明 继而根据不同的情形。 展开更多
关键词 3-D环面解 余维二 分岔 转迁集
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基于多尺度方法的1∶3共振双Hopf分岔分析
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作者 王万永 陈丽娟 郭静 《郑州大学学报(理学版)》 CAS 北大核心 2016年第3期23-27,共5页
利用改进的多尺度方法对一个电路振子模型1∶3共振附近的动力学行为进行了研究.应用该方法得到了系统的复振幅方程,进而得到一个振幅与相位解耦的三维实振幅系统,通过分析实振幅方程的平衡点个数及其稳定性,将系统共振点附近的动力学行... 利用改进的多尺度方法对一个电路振子模型1∶3共振附近的动力学行为进行了研究.应用该方法得到了系统的复振幅方程,进而得到一个振幅与相位解耦的三维实振幅系统,通过分析实振幅方程的平衡点个数及其稳定性,将系统共振点附近的动力学行为进行分类,发现了双稳态等动力学现象,数值模拟验证了理论结果的正确性. 展开更多
关键词 电路振子 1∶3共振 多尺度方法 分岔
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3-溴咔唑-9-乙酸晶体中的分叉型氢键及其理论分析
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作者 劳文剑 宋翠华 +1 位作者 尤进茂 欧庆瑜 《化学研究》 CAS 2012年第5期40-43,共4页
用半经验量子化学AM1方法分析了化合物3-溴咔唑-9-乙酸的分子构象.结果表明,化合物3-溴咔唑-9-乙酸晶体存在分子间非对称分叉型氢键;该非对称分叉型氢键支配化合物的堆积结构.与此同时,同咔唑环氮原子相连的羧甲基易在一定范围内摆动,... 用半经验量子化学AM1方法分析了化合物3-溴咔唑-9-乙酸的分子构象.结果表明,化合物3-溴咔唑-9-乙酸晶体存在分子间非对称分叉型氢键;该非对称分叉型氢键支配化合物的堆积结构.与此同时,同咔唑环氮原子相连的羧甲基易在一定范围内摆动,分叉型氢键是晶体状态下和真空中羧甲基位置变化的原因之一;非对称分叉型氢键使分子体系得到4.97kJ/mol的额外稳定作用能. 展开更多
关键词 3-溴咔唑-9-乙酸 晶体结构 分叉型氢键 AM1方法 理论分析
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一类(3+1)维非线性Jaulent-Miodek分层发展方程的行波解分岔(英文)
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作者 何斌 赵立通 +1 位作者 李静 田征 《上海师范大学学报(自然科学版)》 2018年第3期305-314,共10页
应用动力系统分岔理论研究一类(3+1)维非线性Jaulent-Miodek分层发展方程的行波解分岔,根据分岔参数的不同值得到非线性变换系统的相图.通过计算得到(3+1)维非线性Jaulent-Miodek分层发展方程的精确行波解,包括周期波解、孤立波解、扭... 应用动力系统分岔理论研究一类(3+1)维非线性Jaulent-Miodek分层发展方程的行波解分岔,根据分岔参数的不同值得到非线性变换系统的相图.通过计算得到(3+1)维非线性Jaulent-Miodek分层发展方程的精确行波解,包括周期波解、孤立波解、扭波解及反扭波解. 展开更多
关键词 (3+1)维非线性发展方程 分岔 行波解 精确解
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The Microwave-assisted Preparation and X-Ray Structure of 3-Bromocarbazole-N-Acetic Acid 被引量:1
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作者 Wen Jian LAO Yu Hua ZHANG +3 位作者 Yue Qi LIU Qiang Jin WU Zi Xiang HUANG Qing Yu OU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第4期321-324,共4页
The rapid synthesis of 3-bromocarbarole-N-acetic acid was performed using microwave irradiation. Under the optimal conditions the yield was 85.6% . The crystal structure showed that the carboxylic groups form bifurcat... The rapid synthesis of 3-bromocarbarole-N-acetic acid was performed using microwave irradiation. Under the optimal conditions the yield was 85.6% . The crystal structure showed that the carboxylic groups form bifurcated hydrogen bonds and the hydroxyl oxygen atoms serve as proton donors and also acceptor. Each carboxylic group was involved in four hydrogen bonds. The package of crystal was dominated by links of these hydrogen bonds. 展开更多
关键词 Microwave-assisted synthesis 3-bromocarbazole-N-acetic acid X-ray determination bifurcated hydrogen bonds.
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(3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程的分支分析及其行波解 被引量:5
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作者 张雪 孙峪怀 《应用数学和力学》 CSCD 北大核心 2019年第12期1345-1355,共11页
首先,运用拟设方法和动力系统分支方法,获得了(3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程的奇异孤子解、亮孤子解、拓扑孤子解、周期爆破波解、孤立波解等.再利用MAPLE软件画出了KdV-Zakharov-Kuznetsov方程在不同条件下的分支相图.... 首先,运用拟设方法和动力系统分支方法,获得了(3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程的奇异孤子解、亮孤子解、拓扑孤子解、周期爆破波解、孤立波解等.再利用MAPLE软件画出了KdV-Zakharov-Kuznetsov方程在不同条件下的分支相图.最后,讨论了行波解之间的联系. 展开更多
关键词 (3+1)维时间分数阶KdV-Zakharov-Kuznetsov方程 拟设方法 分支方法 分支相图 行波解
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广义的(3+1)维Kadomtsev-Petviashvili方程的动力分析及其行波解 被引量:3
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作者 张雪 孙峪怀 《数学物理学报(A辑)》 CSCD 北大核心 2019年第3期501-509,共9页
运用拟设方法和动力系统分支方法,获得了广义(3+1)维Kadomtsev-Petviashvili方程的奇异孤子解及其行波解.
关键词 广义的(3+1)维Kadomtsev-Petviashvili方程 拟设方法 分支方法 分支相图 行波解
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1/3 SUBHARMONIC SOLUTION OF ELLIPTICAL SANDWICH PLATES
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作者 李银山 张年梅 杨桂通 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第10期1147-1157,共11页
The problem of nonlinear forced oscillations for elliptical sandwich plates is dealt with. Based on the governing equations expressed in terms of five displacement components, the nonlinear dynamic equation of an elli... The problem of nonlinear forced oscillations for elliptical sandwich plates is dealt with. Based on the governing equations expressed in terms of five displacement components, the nonlinear dynamic equation of an elliptical sandwich plate under a harmonic force is derived. A superpositive-iterative harmonic balance (SIHB) method is presented for the steady-state analysis of strongly nonlinear oscillators. In a periodic oscillation, the periodic solutions can be expressed in the form of basic harmonics and bifurcate harmonics. Thus, an oscillation system which is described as a second order ordinary differential equation, can be expressed as fundamental differential equation with fundamental harmonics and incremental differential equation with derived harmonics. The 1/3 subharmonic solution of an elliptical sandwich plate is investigated by using the methods of SIHB. The SIHB method is compared with the numerical integration method. Finally, asymptotical stability of the 1/3 subharmonic oscillations is inspected. 展开更多
关键词 elliptical sandwich plate superpositive-iterative harmonic balance (SIHB) method 1/3 subharmonic solution bifurcation
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Rescue treatment and follow-up intervention of a left main acute myocardial infarction with typical carina shift under 3D optical coherence tomography: A case report
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作者 Bei-Bei Du Ya-Liang Tong +4 位作者 Xing-Tong Wang Guo-Hui Liu Kun Liu Ping Yang Yu-Quan He 《World Journal of Clinical Cases》 SCIE 2020年第4期848-853,共6页
BACKGROUND Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists.Left main(LM)bifurcation lesions have a higher risk due to the vast blood supply in this area and treatmen... BACKGROUND Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists.Left main(LM)bifurcation lesions have a higher risk due to the vast blood supply in this area and treatment choice is difficult.Ostial compromise of the side branch decreases patient prognosis,and its management is still an issue despite the different strategies and devices available.CASE SUMMARY A 42-year-old male patient was admitted to hospital due to chest pain and syncope.Coronary angiography showed acute LM occlusion.Following thrombus aspiration,a LM bifurcation lesion remained.Coronary angiography was repeated one week later,and at the same time,3D optical coherence tomography(OCT)was carried out to better show the geometry of the bifurcation,which confirmed that the stenosis in the ostial left circumflex artery was caused by a long carina.After assessment of the plaque characteristics and the minimum lumen area,the cross-over strategy,kissing balloon inflation and proximal optimization technique were chosen to treat the bifurcation lesion.A“moving”carina was found twice during the intervention.Good stent apposition and expansion were confirmed by OCT after proximal optimization technique.The three-month follow-up showed good recovery and normal cardiac function.CONCLUSION 3D-OCT can facilitate decision-making for coronary interventions in patients with critical bifurcation lesions. 展开更多
关键词 3-Dimensional optical coherence tomography Left main bifurcation Acute myocardial infarction Carina shift Kissing balloon inflation Case report
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Bifurcation and Chaotic Dynamics of Homoclinic Systems in R^3 被引量:2
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作者 Sun Jianhua Department of Mathematics Nanjing University Nanjing, 210008 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第2期128-136,共9页
We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic ... We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic orbits, and illustrate our results with two examples. 展开更多
关键词 bifurcation and Chaotic Dynamics of Homoclinic Systems in R~3
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GLOBAL BIFURCATIONS IN A DISTURBED HAMILTONIAN VECTOR FIELD APPROACHING A 3:1 RESONANT POINCAR MAP (Ⅰ) 被引量:1
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作者 李继彬 万世栋 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1991年第1期80-89,共10页
In this paper, we use a qualitative method to study global and local bifurcations in a disturbedHamiltonian vector field approaching a Poincare map in the 3:1 resonant case. We give explicitcalculation formulas to det... In this paper, we use a qualitative method to study global and local bifurcations in a disturbedHamiltonian vector field approaching a Poincare map in the 3:1 resonant case. We give explicitcalculation formulas to determine bifurcation parameters and draw various bifurcations and phaseportraits in the phase plane. 展开更多
关键词 GLOBAL bifurcationS IN A DISTURBED HAMILTONIAN VECTOR FIELD APPROACHING A 3 MAP
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Bifurcation Method to Analysis of Traveling Wave Solutions for(3+l)-Dimensional Nonlinear Models Generated by the Jaulent-Miodek Hierarchy
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作者 RAN Yanping LI jing 《Journal of Partial Differential Equations》 CSCD 2018年第4期304-321,共18页
In this paper,the third model of four(3+1)-dimensional nonlinear evolution equations,generated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation method of planar dynamical systems.The 2-parameters dif... In this paper,the third model of four(3+1)-dimensional nonlinear evolution equations,generated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation method of planar dynamical systems.The 2-parameters different bifurcation regions are obtained.According to the different phase portraits in 2-parameters different bifurcation regions,we obtain kink(anti-kink)wave solutions,solitary wave solutions and periodic wave solutions for the third of these models in the different subsets of 4-parameters space by dynamical system method.Furthermore,the explicit exact expressions of these bounded traveling waves are obtained.All these wave solutions are characterized by distinct physical structures. 展开更多
关键词 Nonlinear(3+1)-dimensional equation bifurcation method TRAVELING wave solution
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基于知识工程模板的月牙肋岔管参数化设计 被引量:13
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作者 韩晓凤 文强 厉海元 《水利水电技术》 CSCD 北大核心 2015年第11期50-55,共6页
基于CATIA软件的知识工程技术,提出了月牙肋钢岔管的三维参数化设计方法。选取合适的定位条件,并通过建立参数关联实现用户输入参数与草图、三维模型之间的驱动关系,建立了通用的月牙肋岔管的设计模板。采用该模板可以快速确定月牙肋岔... 基于CATIA软件的知识工程技术,提出了月牙肋钢岔管的三维参数化设计方法。选取合适的定位条件,并通过建立参数关联实现用户输入参数与草图、三维模型之间的驱动关系,建立了通用的月牙肋岔管的设计模板。采用该模板可以快速确定月牙肋岔管多种设计方案,并导入有限元软件进行结构分析,获得最终设计方案。在三维模型上进行焊缝分缝设计后,借助曲面展开功能获得管节展开图,并自动生成控制点坐标表和材料表。该设计方法以建立模板为核心,整合了岔管参数化建模、有限元结构分析、焊缝分缝设计和绘制岔管展开图四大功能,满足了月牙肋岔管施工详图阶段的设计需求,在工程应用中显示了设计效率高的优点。 展开更多
关键词 月牙肋岔管 三维参数化设计 知识工程 模板
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