We study solutions of the nonlinear Schroedinger equation （NLSE） and higher-order nonlinear Sehroedinger equation （HONLSE） with variable coefficients. By considering all the higher-order effect of HONLSE as a new ...We study solutions of the nonlinear Schroedinger equation （NLSE） and higher-order nonlinear Sehroedinger equation （HONLSE） with variable coefficients. By considering all the higher-order effect of HONLSE as a new dependent variable, the NLSE and HONLSE can be changed into one equation. Using the generalized Lie group reduction method （CLGRM）, the abundant solutions of NLSE and HONLSE are obtained.展开更多
Various types of wave group solutions of the weakly nonlinear waves may exist over uneven bottoms. In this paper, the variation of the zeroes of the dispersive and nonlinear terms,and the wave group solution in the th...Various types of wave group solutions of the weakly nonlinear waves may exist over uneven bottoms. In this paper, the variation of the zeroes of the dispersive and nonlinear terms,and the wave group solution in the third-order evolution equations are described for the case of mild and locally fastvarying water depths.展开更多
Nonlinear optics,which is a subject for studying the interaction between intense light and materials,has great impact on various research fields.Since many structures in biological tissues exhibit strong nonlinear opt...Nonlinear optics,which is a subject for studying the interaction between intense light and materials,has great impact on various research fields.Since many structures in biological tissues exhibit strong nonlinear optical effects,nonlinear optics has been widely applied in biomedical studies.Especially in the aspect of bio-imaging,nonlinear optical techniques can provide rapid,label-free and chemically specific imaging of biological samples,which enable the investigation of biological processes and analysis of samples beyond other microscopy techniques.In this review,we focus on the introduction of nonlinear optical processes and their applications in bio-imaging as well as the recent advances in this filed.Our perspective of this field is also presented.展开更多
This paper deals with the Alienor method to tackle multiobjective nonlinear optimization problems. In this approach, the multiple criteria of the optimization problem are aggregated into a single one using weighted su...This paper deals with the Alienor method to tackle multiobjective nonlinear optimization problems. In this approach, the multiple criteria of the optimization problem are aggregated into a single one using weighted sums. Then, the resulting single objective nonlinear optimization problem is solved using the Alienor method associated with the Optimization Preserving Operators technique which has proved to be suitable for (nonlinear) optimization problems with a large number of variables (see [1]). The proposed approach is evaluated through test problems. The results show that the approach provides good approximations of the Pareto front while requiring small computational time, even for large instances.展开更多
Competitive learning has attracted a signif- icant amount of attention in the past decades in the field of data clustering. In this paper, we will present two works done by our group which address the nonlin- early se...Competitive learning has attracted a signif- icant amount of attention in the past decades in the field of data clustering. In this paper, we will present two works done by our group which address the nonlin- early separable problem suffered by the classical com- petitive learning clustering algorithms. They are ker- nel competitive learning （KCL） and graph-based multi- prototype competitive learning （GMPCL）, respectively. In KCL, data points are first mapped from the input data space into a high-dimensional kernel space where the nonlinearly separable pattern becomes linear one. Then the classical competitive learning is performed in this kernel space to generate a cluster structure. To real- ize on-line learning in the kernel space without knowing the explicit kernel mapping, we propose a prototype de- scriptor, each row of which represents a prototype by the inner products between the prototype and data points as well as the squared length of the prototype. In GM- PCL, a graph-based method is employed to produce an initial, coarse clustering. After that, a multi-prototype competitive learning is introduced to refine the coarse clustering and discover clusters of an arbitrary shape. In the multi-prototype competitive learning, to gener- ate cluster boundaries of arbitrary shapes, each cluster is represented by multiple prototypes, whose subregions of the Voronoi diagram together approximately charac- terize one cluster of an arbitrary shape. Moreover, we introduce some extensions of these two approaches with experiments demonstrating their effectiveness.展开更多
A series of new poly(ferrocenylenesilanes) containing carbazole as charge transporting agent and Dispersed Red 1 (DR-1) as second-order nonlinear optical (NLO) chromophore was synthesized. The resulting polymers repre...A series of new poly(ferrocenylenesilanes) containing carbazole as charge transporting agent and Dispersed Red 1 (DR-1) as second-order nonlinear optical (NLO) chromophore was synthesized. The resulting polymers represent the first example of NLO polymer with ferrocenyl groups in the backbone. This series of polymers was characterized with H-1 NMR, UV-vis, IR spectroscopies, differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). A preliminary measurement on NLO property of the polymers was carried out with in-situ second-harmonic generation (SHG) measurement.展开更多
伴随着光纤技术的快速发展,光纤网络已部署于航空航天、舰船、数据中心和工业物联网中。传统的光时域反射仪(optical time domain reflectometer,OTDR)因原理限制,难以实现高分辨率测试,在上述复杂场景中应用受限。基于瑞利散射的光频...伴随着光纤技术的快速发展,光纤网络已部署于航空航天、舰船、数据中心和工业物联网中。传统的光时域反射仪(optical time domain reflectometer,OTDR)因原理限制,难以实现高分辨率测试,在上述复杂场景中应用受限。基于瑞利散射的光频域反射(optical frequency domain reflection,OFDR)技术可实现极高的空间分辨率、高传感灵敏度和快速的测试速率,该系列产品适用于光器件、光模块、短距离光网络的测试和故障排除,可实现从器件到光学链路全范围的插损、回损和长度测量。文中基于光频域反射法原理设计实现了一套光纤链路检测系统,针对偏振衰落效应和激光器非线性扫频等难题进行了研究,在112 m的测试链路上实现了20μm空间分辨率。展开更多
无线传感器网络中基于到达时间TOA(time of arrival)的定位算法需要建立关于未知节点与锚节点距离的非线性方程。牛顿迭代法是求解非线性线方程数值解的有效方法。分析了一种基于牛顿迭代法求解TOA定位非线性方程的算法,提出了对应的牛...无线传感器网络中基于到达时间TOA(time of arrival)的定位算法需要建立关于未知节点与锚节点距离的非线性方程。牛顿迭代法是求解非线性线方程数值解的有效方法。分析了一种基于牛顿迭代法求解TOA定位非线性方程的算法,提出了对应的牛顿迭代式。仿真结果表明,此算法可以满足定位的需求,且具有比经典CHAN算法更高的定位精度。展开更多
爆炸活塞式高速开断装置的炸药腔室结构直接影响混合型限流熔断器的动力、电气性能,不合理的结构会使动子获得的动能降低,导致分断能力下降甚至分断失败。针对此问题,以LS-DYNA为仿真平台建立了非线性动力学模型,对炸药腔室的结构进行...爆炸活塞式高速开断装置的炸药腔室结构直接影响混合型限流熔断器的动力、电气性能,不合理的结构会使动子获得的动能降低,导致分断能力下降甚至分断失败。针对此问题,以LS-DYNA为仿真平台建立了非线性动力学模型,对炸药腔室的结构进行了研究,得到了冲击波在炸药腔室内的传播规律,并分别分析了炸药与活塞距离、活塞半径、药腔半径对开断性能的影响,结果表明炸药腔室结构参数存在最优值。最后设计了额定900 V/1 000 A的装置样机进行了分断特性和短路开断试验,试验中开断器动子位移与仿真一致,样机成功分断了预期峰值40 k A、电流上升率12 A/μs的短路电流,机械刚分时间为84μs,短路电流峰值被限制在22.7 k A,表明仿真模型与相关研究结论可用于指导爆炸活塞式高速开断器的结构优化设计。展开更多
基金National Natural Science Foundation of China under Grant No.10675065
文摘We study solutions of the nonlinear Schroedinger equation （NLSE） and higher-order nonlinear Sehroedinger equation （HONLSE） with variable coefficients. By considering all the higher-order effect of HONLSE as a new dependent variable, the NLSE and HONLSE can be changed into one equation. Using the generalized Lie group reduction method （CLGRM）, the abundant solutions of NLSE and HONLSE are obtained.
文摘Various types of wave group solutions of the weakly nonlinear waves may exist over uneven bottoms. In this paper, the variation of the zeroes of the dispersive and nonlinear terms,and the wave group solution in the third-order evolution equations are described for the case of mild and locally fastvarying water depths.
基金the National Natural Science Foundation of China(61722508/61525503/61620106016/61835009/61935012/61961136005)(Key)Project of Department of Education of Guangdong Province(2016KCXTD007)Shenzhen Basic Research Project(JCYJ20180305124902165).
文摘Nonlinear optics,which is a subject for studying the interaction between intense light and materials,has great impact on various research fields.Since many structures in biological tissues exhibit strong nonlinear optical effects,nonlinear optics has been widely applied in biomedical studies.Especially in the aspect of bio-imaging,nonlinear optical techniques can provide rapid,label-free and chemically specific imaging of biological samples,which enable the investigation of biological processes and analysis of samples beyond other microscopy techniques.In this review,we focus on the introduction of nonlinear optical processes and their applications in bio-imaging as well as the recent advances in this filed.Our perspective of this field is also presented.
文摘This paper deals with the Alienor method to tackle multiobjective nonlinear optimization problems. In this approach, the multiple criteria of the optimization problem are aggregated into a single one using weighted sums. Then, the resulting single objective nonlinear optimization problem is solved using the Alienor method associated with the Optimization Preserving Operators technique which has proved to be suitable for (nonlinear) optimization problems with a large number of variables (see [1]). The proposed approach is evaluated through test problems. The results show that the approach provides good approximations of the Pareto front while requiring small computational time, even for large instances.
文摘Competitive learning has attracted a signif- icant amount of attention in the past decades in the field of data clustering. In this paper, we will present two works done by our group which address the nonlin- early separable problem suffered by the classical com- petitive learning clustering algorithms. They are ker- nel competitive learning （KCL） and graph-based multi- prototype competitive learning （GMPCL）, respectively. In KCL, data points are first mapped from the input data space into a high-dimensional kernel space where the nonlinearly separable pattern becomes linear one. Then the classical competitive learning is performed in this kernel space to generate a cluster structure. To real- ize on-line learning in the kernel space without knowing the explicit kernel mapping, we propose a prototype de- scriptor, each row of which represents a prototype by the inner products between the prototype and data points as well as the squared length of the prototype. In GM- PCL, a graph-based method is employed to produce an initial, coarse clustering. After that, a multi-prototype competitive learning is introduced to refine the coarse clustering and discover clusters of an arbitrary shape. In the multi-prototype competitive learning, to gener- ate cluster boundaries of arbitrary shapes, each cluster is represented by multiple prototypes, whose subregions of the Voronoi diagram together approximately charac- terize one cluster of an arbitrary shape. Moreover, we introduce some extensions of these two approaches with experiments demonstrating their effectiveness.
基金theEducationMinistryofChinaandbyagrant (No .990 78)fromtheNationalKeyFundamentalResearchPro gramofChina
文摘A series of new poly(ferrocenylenesilanes) containing carbazole as charge transporting agent and Dispersed Red 1 (DR-1) as second-order nonlinear optical (NLO) chromophore was synthesized. The resulting polymers represent the first example of NLO polymer with ferrocenyl groups in the backbone. This series of polymers was characterized with H-1 NMR, UV-vis, IR spectroscopies, differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). A preliminary measurement on NLO property of the polymers was carried out with in-situ second-harmonic generation (SHG) measurement.
文摘伴随着光纤技术的快速发展,光纤网络已部署于航空航天、舰船、数据中心和工业物联网中。传统的光时域反射仪(optical time domain reflectometer,OTDR)因原理限制,难以实现高分辨率测试,在上述复杂场景中应用受限。基于瑞利散射的光频域反射(optical frequency domain reflection,OFDR)技术可实现极高的空间分辨率、高传感灵敏度和快速的测试速率,该系列产品适用于光器件、光模块、短距离光网络的测试和故障排除,可实现从器件到光学链路全范围的插损、回损和长度测量。文中基于光频域反射法原理设计实现了一套光纤链路检测系统,针对偏振衰落效应和激光器非线性扫频等难题进行了研究,在112 m的测试链路上实现了20μm空间分辨率。
文摘无线传感器网络中基于到达时间TOA(time of arrival)的定位算法需要建立关于未知节点与锚节点距离的非线性方程。牛顿迭代法是求解非线性线方程数值解的有效方法。分析了一种基于牛顿迭代法求解TOA定位非线性方程的算法,提出了对应的牛顿迭代式。仿真结果表明,此算法可以满足定位的需求,且具有比经典CHAN算法更高的定位精度。
文摘爆炸活塞式高速开断装置的炸药腔室结构直接影响混合型限流熔断器的动力、电气性能,不合理的结构会使动子获得的动能降低,导致分断能力下降甚至分断失败。针对此问题,以LS-DYNA为仿真平台建立了非线性动力学模型,对炸药腔室的结构进行了研究,得到了冲击波在炸药腔室内的传播规律,并分别分析了炸药与活塞距离、活塞半径、药腔半径对开断性能的影响,结果表明炸药腔室结构参数存在最优值。最后设计了额定900 V/1 000 A的装置样机进行了分断特性和短路开断试验,试验中开断器动子位移与仿真一致,样机成功分断了预期峰值40 k A、电流上升率12 A/μs的短路电流,机械刚分时间为84μs,短路电流峰值被限制在22.7 k A,表明仿真模型与相关研究结论可用于指导爆炸活塞式高速开断器的结构优化设计。
