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Non-Lie Symmetry Groups of （2＋1）-Dimensional Nonlinear Systems

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Communications in Theoretical Physics 2006年第6X期46卷 1005-1010页

作者： ma hong-cai LOU Sen-Yue Department of mathematics Donghua University Shanghai 200051 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physics systems. Applying the modified direct method to the well-known （2＋1）-dimensional asymmetric Nizhnik-Novikov-Vesselov equation and Nizhnik Novikov-Vesselov equation, both the Lie point symmetry groups and the non-Lie symmetry groups are obtained. The Lie symmetry groups obtained via traditional Lie approaches are only speciai cases. Furthermore, the expressions of the exact finite transformations of the Lie groups are much simpler than those obtained via the standard approaches.

关键词： symmetry groups CK direct method symmetries exact solution

Lie Symmetry Groups of(2+1)-Dimensional BKP Equation and Its New Solutions

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Communications in Theoretical Physics 2008年第9期50卷 685-688页

作者： ma hong-cai LOU Sen-Yue DENG Ai-Ping Department of mathematics Donghua University Shanghai 200051 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

A modified direct method is developed to find finite symmetry groups of nonlinear mathematical *** the modified direct method to the well-known (2+1)-dimensional BKP equation we get its ***,the exact solutions of (2+1... 详细信息

关键词： (2+1)-dimensional BKP equation Lie symmetry group CK's direct method exact solution

New Exact Travelling Wave Solutions for Zakharov-Kuznetsov Equation

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Communications in Theoretical Physics 2009年第4期51卷 609-612页

作者： ma hong-cai YU Yao-Dong GE Dong-Jie Department of Applied mathematics College of Science Donghua University Shanghai 201620 China

In this paper, the nonlinear dispersive Zakharov- Kuznetsov equation is solved by using the generalized auxiliary equation method. As a result, new solitary pattern, solitary wave and singular solitary wave solutions ... 详细信息

关键词： Zakharov Kuznetsov equation auxiliary equation method exact solutions

New Periodic Wave Solutions and Their Interaction for （2＋1）-dimensional KdV Equation

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Chinese Quarterly Journal of mathematics 2009年第4期24卷 525-536页

作者： GE Dong-jie ma hong-cai YU Yao-dong College of Science Donghua University Shanghai 201620 China

A class of new doubly periodic wave solutions for （2＋1）-dimensional KdV equation are obtained by introducing appropriate Jacobi elliptic functions and Weierstrass elliptic functions in the general solution（contains two arbitrary functions） got by means of multilinear variable separation approach for （2＋1）-dimensional KdV equation. Limiting cases are considered and some localized excitations are derived, such as dromion, multidromions, dromion-antidromion, multidromions-antidromions, and so on. Some solutions of the dromion-antidromion and multidromions-antidromions are periodic in one direction but localized in the other direction. The interaction properties of these solutions, which are numerically studied, reveal that some of them are nonelastic and some are completely elastic. Furthermore, these results are visualized.

关键词： (2+1)-dimensional KdV equation multilinear variable separation approach elliptic functions periodic wave solutions localized excitations interaction property nonelastic completely elastic

Comparison of the major malformation rate of children conceived from cryopreserved embryos and fresh embryos

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Chinese Medical Journal 2010年第14期123卷 1893-1897页

作者： LI hong-zhen QIAO Jie CHI hong-bin CHEN Xin-na LIU Ping ma cai-hong Medical Center -for Human Reproduction Department of Obstetrics and Gynecology Peking University Third Hospital Beijing 100191 China

Background Cryopreserved embryo transfer has become indispensable in reproductive technology. More and more children are conceived from frozen-thawed embryo transfer （FET）. The risk of birth defects associated with frozen-thawed embryo transfer has been evaluated and conflict results are obtained. The aim of this study was to compare the rate of major malformations in children conceived from cryopreserved embryos with that of children from fresh embryos. Methods A retrospective analysis was performed on children conceived from frozen-thawed embryos and fresh embryos between January 2005 and December 2008 at the Reproduction Center of the Third Hospital, Peking University. The major malformation rates were compared between two groups for all children, as welt as singletons or twins, separately. The frequencies of different subtypes of malformations classified according to different organ system were also compared. Results Thirty-four of 3125 children from cryopreserved embryos had a major malformation. The malformation rate was 1.09%, which was comparable to that for children after fresh embryos transfer （1.53%（55/3604）, OR： 0.71, 95%Cl; 0.46-1.09）. The malformation rate was also similar when the analysis was limited to children from cryopreserved embryos resulted from in vitro fertilization （IVF）（1.39%）and fresh IVF（1.3%）. However, children from cryopreserved embryos resulted from intracytoplasmic sperm injections （ICSI） had much lower malformation rate than from fresh ICS1（0.63% vs.1.83%, OR： 0.34, 95% CI： 0.16-0.75）. No difference was found in the incidence of major malformations in singletons from cryo ICSI （0.73%） and fresh ICS1（1.9%）, or from cryo IVF（1.49%） and fresh IVF（1.67%）. Similar malformation rate was found in multiples from cryo ICS1（0.52%） and fresh ICS1（1.76%）, or cryo IVF（1.30%） and fresh IVF（0.90%）. The distribution and risk of the subtype of malformations, such as cardiovascular, gastrointestinal, neural tube, urogenital, musculoskeletal and facia

关键词： congenital malformation fertilization in vitro sperm injections, intracytoplasmic frozen-thawed embryo transfer

Efficacy of local aspiration in the conservative treatment of live interstitial pregnancy coexisting with live intrauterine pregnancy after in vitro fertilization and embryo transfer

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Chinese Medical Journal 2012年第7期125卷 1345-1348页

作者： WANG Yang ma cai-hong QIAO Jie CHEN Xin-na LIU Ping Center for Reproductive Medicine Peking University Third HospitalBeijing 100191China

Background Heterotopic pregnancy （HP） is defined as a pregnancy in which one or more embryos is viably implanted in the uterus while the other is implanted elsewhere as an ectopic pregnancy. The occurrence of HP rises dramatically with the increased use of assisted reproductive technology. HP of interstitial pregnancy is one special situation which needs more concern. Here we evaluate the efficacy of local aspiration and instillation of hyperosmolar glucose in the treatment of live interstitial pregnancy complicated with live intrauterine pregnancy after in vitro fertilization and embryo transfer. Methods Five female patients were diagnosed with live interstitial pregnancies complicated with intrauterine pregnancies. They were treated with transvaginal ultrasound-guided aspiration of interstitial pregnancy and instillation of hyperosmolar glucose at the Center for Reproductive Medicine of Peking University Third Hospital from January 1st, 2008 to may 30th, 2011. Results Gemmule embryos in all 5 cases were aspirated successfully and there was no abdominal hemorrhage, threatened abortion or infection in any of the cases. The sac of interstitial pregnancy continued to progress after aspiration and stopped growing between 11 to 20 weeks. By the 30th week of pregnancy, 80% of the interstitial masses had disappeared. Four cases have delivered and one is still in on-going pregnancy. All of the four cases underwent cesarean section and there were nothing special detected in the corner of the uterus. Conclusion Local aspiration and instillation of hyperosmolar glucose may be an effective way to treat live interstitial pregnancy when coexisting with a live intrauterine pregnancy.

关键词： interstitial pregnancy heterotopic pregnancy fetocide in vitro fertilization,"transvaginal ultrasound-guided aspiration

Auxiliary Equation Method and New Exact Solutions of BKP Equation

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Chinese Quarterly Journal of mathematics 2008年第2期23卷 159-164页

作者： ma hong-cai ZHANG Ya-li DENG Ai-ping College of Science Donghua University Shanghai 201620 China Department of mathematics and Computer Science Xinyang Vocational and Technical College Xinyang 464000 China

In this paper, auxiliary equation method is proposed for constructing more general exact solutions of nonlinear partial differential equation with the aid of symbolic computation. We study the （2＋1）-dimensional BKP equation and get a series of new types of traveling wave solutions. The method used here can be also extended to other nonlinear partial differential equations.

关键词： (2+1)-dimensional BKP equation auxiliary equation method traveling wave solution nonlinear

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基于足迹家族的青海省资源环境压力定量评估

应用生态学报 2016年第4期27卷 1248-1256页

作者：马彩虹赵晶宁夏大学资源环境学院银川750021 西安石油大学思想政治理论教学科研部西安710065

为了系统评估人类活动对环境的影响,基于足迹家族构建了资源环境压力评价体系,对青海省的生态足迹、碳足迹、水足迹及资源环境压力作了测评.结果表明:1990—2013年,青海省人均生态足迹由1.32 hm^2增为3.32 hm^2,人均生物承载力由2.33 h... 详细信息

为了系统评估人类活动对环境的影响,基于足迹家族构建了资源环境压力评价体系,对青海省的生态足迹、碳足迹、水足迹及资源环境压力作了测评.结果表明:1990—2013年,青海省人均生态足迹由1.32 hm^2增为3.32 hm^2,人均生物承载力由2.33 hm^2降至2.07 hm^2,2006年后出现生态赤字且不断增高,但1990年以来始终存在生物质盈余;人均碳足迹由5.82 t增至15.85 t,目前已超过应对气候变化目标的7.93倍;人均水足迹从967.67m3降低到732.05 m3.1990年以来生态压力一直较低(Ⅰ_b),温室气体(GHG)排放压力由较低(Ⅰ_b)升高到中上(Ⅱ_b),水资源压力很低(Ⅰ_a),资源环境压力由很低(Ⅰ_a)升高为较低(Ⅰ_b).生态压力和水资源压力对资源环境压力的贡献率逐渐降低,GHG排放压力的影响明显增大.资源环境压力的空间差异较大,2013年西宁市很高(Ⅲ_b)、海东市中上(Ⅱ_b)、海西州中下(Ⅱ_a),其他各市州很低(Ⅰ_a),主要压力源也具有明显的空间异质性.今后发展中,各市州应采取差异化减压策略.

关键词：足迹家族生态足迹碳足迹水足迹资源环境压力

干涉型分布式光纤漏检系统的偏振控制技术研究

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光通信技术 2011年第5期35卷 40-43页

作者：马彩虹武警工程学院通信工程系光纤通信实验室西安710086

在长距离分布式光纤传感系统中,光输出偏振态往往会发生漂移,影响了传感系统的干涉效果。针对典型的双马赫-曾德尔分布式光纤漏检系统,从理论上分析了偏振退化对系统性能的影响。重点阐述了采用偏振分集接收技术和使用法拉第旋转镜等技... 详细信息

在长距离分布式光纤传感系统中,光输出偏振态往往会发生漂移,影响了传感系统的干涉效果。针对典型的双马赫-曾德尔分布式光纤漏检系统,从理论上分析了偏振退化对系统性能的影响。重点阐述了采用偏振分集接收技术和使用法拉第旋转镜等技术进行偏振控制,仿真表明这两项技术都能很好地达到偏振控制的效果。

关键词：分布式光纤传感偏振态马赫-曾德尔干涉仪分集检测