反向传输中高阶色散项的交叉相位调制不稳定性分析

对在光纤中反向传输的两束光,以包含了三、四阶色散项的耦合非线性薛定谔方程为基础,主要研究高阶色散对交叉相位调制不稳定性的影响.三阶色散对调制不稳定性不起作用,但反向传输光的群速度却对不稳定性的发生有影响;当满足一定条件时,由于四阶色散的影响,在光纤的反常色散区,交叉相位调制不稳定性发生在两个频谱区.在正常色散区,四阶色散产生了一个新的交叉相位调制不稳定性频谱区;反常色散区远离零点的频谱区的增益谱比正常色散区的增益谱更靠近零点,且两个频谱区的范围有准分离的对称关系.     

基于旅游认识不稳定性的目的地文化部落建设

旅游社会依赖于生活系统并处于不断发展过程中,旅游主体的经验也受到年龄等各方面的影响,旅游认识又由旅游社会、旅游主体所决定,因而推论旅游认识具有不稳定性。借用了熵理论与现代物理学的宇宙不对称性观点进一步阐述了旅游认识不稳定性这一命题。在泛指旅游认识具有不稳定性的基础上,本文认为局地上的旅游建设应以生活系统作为支撑,并坚持文化部落性,通过地方感与真实性的共建,可持续性地保持并增强目的地的活力。     

中国纺织品出口地理结构与出口不稳定性分析

以地理集中化指标、出口多样化指数等为研究变量,实证分析中国纺织品出口地理结构与其出口不稳定性的相互关系,结果显示:中国纺织品出口主要集中在亚洲地区,亚洲市场的波动决定了中国纺织品出口不稳定性的大部分,而来自亚洲市场的冲击可由其他几大洲市场部分地平抑;不断扩大的欧美市场由于其自身的不稳定性及波动的趋势相关性,对亚洲市场的平抑作用十分有限;通过出口地理结构调整,开拓新的市场尤其是非洲市场可以降低总体出口的不稳定性.     

对浓硝酸几种性质的实验探究

浓硝酸是中学化学中常用的一种酸,它除具有酸的某些通性外,还具有一些特性,如强氧化性、不稳定性等.中学化学教材对浓硝酸的强氧化性、不稳定性等性质的描述比较笼统,为此,我们进行了较为具体的实验探究.     

一类三次系统的定性研究

讨论了一类三次系统的性质,证明了零平衡点的不稳定性,同时林到了系统的一类特解．     

浅析农地产权的不稳定性对农村经济可持续发展的影响

我国农村实行土地承包责任制存在的主要问题就是农地产权的不稳定性,这一缺陷严重制约了我国农村经济的发展。这种不稳定性的原因是多方面的,根本原因是土地产权主体虚置。因此我们要继续深化农村土地改革,并通过立法,增强土地产权的稳定性,保护农民的合法权益,调动农民的积极性,进一步解放农村生产力。     

关于高校后勤非编员工党员发展工作的几点思考

1.非编员工党员发展遇到的主要问题1.1工作的不稳定性由于非编用工的劳动关系不稳定,一般只签定短期合同或固定期限合同,使得这部分人员工作岗位面临很大不稳定性,而党员发展是     

基因工程菌发酵过程中的不稳定性研究

从基因工程菌(细胞)的生长动力学模型入手,阐述了导致基因工程菌不稳定的原因及不稳定性的表现;探讨了防止或降低基因工程菌不稳定性的对策,包括组建合适载体、选择适当宿主、施加选择压力、控制基因过量表达及控制培养条件等。     

均匀加宽单模激光的不稳定性

本文用线性稳定性分析方法,对均点加宽情形下的单模行波激光的自脉动不稳定性进行了研究。     

高阶色散和高阶非线性对零色散光纤调制不稳定的影响

利用广义非线性薛定谔方程,研究了零色散光纤中交叉相位调制不稳定性,分析了高阶色散和高阶非线性系数对增益谱的影响.发现当光脉冲工作在零色散附近时,交叉相位调制不稳定性主要取决于四阶色散,它使增益谱变宽.正五阶非线性使增益谱的谱宽和峰值增大,负五阶非线性使增益谱的谱宽和峰值减小.     

Caregiver instability and early life changes among infants reported to the child welfare system

This study describes the extent of caregiver instability (defined as a new placement for 1 week or longer in a different household and/or with a new caregiver) in a nationally representative sample of infants, followed for 5–7 years. Data were drawn from the National Survey of Child and Adolescent Well-Being (NSCAW), a longitudinal study of 5,501 children investigated for child maltreatment. The analysis sample was restricted to 1,196 infants. Overall, 85.6% of children who were infants at the time of the index maltreatment experienced at least one caregiver instability event during their first 2 years of life. Caregiver instability was associated with the child having a chronic health condition and the caregiver being older than 40 years of age at baseline. The levels of instability reported in this study from infancy to school entry are extremely high. Children with more risk factors were significantly more likely to experience caregiver instability than children with fewer risk factors. The repeated loss of a young child's primary caregiver or unavailable, neglectful care can be experienced as traumatic. Some evidence-based programs that are designed to work with young maltreated children can make a substantial positive difference in the lives of vulnerable infants.     

工程结构中非线性动态失稳与分叉理论

In civil engineering, the nonlinear dynamic instability of structures occurs at a bifurcation point or a limit point. The instability at a bifurcation point can be analyzed with the theory of nonlinear dynamics, and that at a limit point can be discussed with the theory of elastoplasticity. In this paper, the nonlinear dynamic instability of structures was treated with mathematical and mechanical theories.The research methods for the problems of structural nonlinear dynamic stability were discussed first, and then the criterion of stability or instability of structures, the method to obtain the bifurcation point and the limit point, and the formulae of the directions of the branch solutions at a bifurcation point were elucidated. These methods can be applied to the problems of nonlinear dynamic instability of structures such as reticulated shells, space grid structures, and so on.     

Some Problems in Nonlinear Dynamic Instability and Bifurcation Theory for Engineering Structures

In civil engineering, the nonlinear dynamic instability of structures occurs at a bifurcation point or a limit point. The instability at a bifurcation point can be analyzed with the theory of nonlinear dynamics, and that at a limit point can be discussed with the theory of elastoplasticity. In this paper, the nonlinear dynamic instability of structures was treated with mathematical and mechanical theories. The research methods for the problems of structural nonlinear dynamic stability were discussed first, and then the criterion of stability or instability of structures, the method to obtain the bifurcation point and the limit point, and the formulae of the directions of the branch solutions at a bifurcation point were elucidated. These methods can be applied to the problems of nonlinear dynamic instability of structures such as reticulated shells, space grid structures, and so on.     

略论腐败

深刻认识腐败的危害,研究腐败的成因,探讨腐败的防治,进而深入正确地开展反腐败斗争。腐败将导致社会政治之不稳定;破坏政府同人民的关系;损害国家和人民的经济利益。腐败产生于经济体制转轨的迟缓、利益导向原则的驱动、权力系统改革原则的不配套、封建特权思想的遗毒。深化体制改革、健全监督机制、加强法制建设等等是根除腐败的关键之点。     

我国大学制度改革发展的基本特征及其分析

制度改革是大学改革的核心内容。我国大学制度改革具有这样三个基本特征:政治因素对大学制度改革起着主导作用;对他国大学制度的“模式移植”过多,而“本土化”创新太少;制度改革中缺乏实证的思想和过程,表现出随意性和不稳定性。     

Schlieren Visualization of Marangoni Effect in Gas-Liquid Systems

This paper is focused on the Marangoni effect in the gas-liquid mass transfer systems. A series of experiments were conducted to observe Marangoni effect by a laser Schlieren system. Experimental investigations of the occurrence of Marangoni convection were presented. The typical polygonal patterns and even the reaching of chaotic interfacial flow were observed. The visual evidences were discussed and the characteristic time and scale of Marangoni convection were obtained approximately as 0.5 s and 1 mm according to the Schlieren images. From the perspective of hydrodynamic instability, the mechanism of the Marangoni convection was investigated. Though many external factors have influence on the interfacial instability, the local surface-tension gradient is the primary reason for the Marangoni convection. The small-scale interfacial flow increases the surface renewal rate. Consequently, due to the occurrence of the Marangoni effect, the mass transfer rate can be significantly enhanced.     

现代化视阈中家庭承包责任制：政治稳定的支撑性因素

在中国现代化进程中,社会政治制度在其中起着关键性的作用。土地家庭承包责任制作为一种极具实践智慧的制度安排,在现代化的背景中与政治稳定有着极大的相关性,这种土地制度为中国在改革开放之后的现代化进程提供了其所需的政治稳定。尽管一般认为现代化会产生不稳定,而现代性才能导致稳定。     

试论公司僵局的法律破解

公司僵局是现实中客观存在的困扰公司发展的问题,并由此引发了资源的浪费、社会稳定等一系列的问题。本文通过分析公司僵局产生的原因入手,认为公司僵局是由现代公司法和公司运行的多数决制度本身造成的,在承认公司僵局将长期存在的同时,也为解决公司僵局提供了几点可供选择的途径。     

建立我国特别收养制度刍议

我国现行收养制度由于收养关系建立的随意性、收养效果的不稳定性等弊端 ,不能充分体现收养制度的本来目的。建立我国特别收养制度很有必要 ,主要应解决如下问题 :限制特别收养关系主体范围 ,严肃特别收养关系成立的形式 ,强化特别收养关系的效果。     

社会转型与宗教格局的变迁——论中国当前制度语境下的新兴宗教

作为现代化和全球化进程中社会发展的重要产物,新兴宗教是社会动荡与制度转型在既有宗教社会格局中的客观反映,对世界各国的政治、经济、文化形态和社会发展进程产生着深刻的影响,其产生与发展离不开对传统文化与既有宗教的有机继承与创造性转换。处在社会转型时期的中国存在新兴宗教产生发展的现实土壤,但在现行制度语境下,由于缺乏必要的制度支持与合法的生存空间,新兴宗教在中国生存艰难。必须客观认识新兴宗教,把握其特点、规律及发展趋势,扬长避短,引导其与社会主义社会相适应,最大限度地发挥其在维护社会稳定中的积极作用。