周期

In this paper,we study the existence.uniqueness and asymptotic stability of the periodic solutions for a class of nonautonomous systems by using the method of Liapunov Function.

利用Liapunov函数方法，研究了一类非自治系统周期解的存在唯一性及渐近稳定性，得到了存在唯一渐近稳定的周期解的充分条件。

This system is permanent by comparative principle and globally asymptotically stable through constructing a Liapunov function; for the periodic case, the research has obtained conditions for existence, uniqueness and stability of a positive periodic solution.

利用比较原理研究了系统的持久性，通过构造Liapunov函数证明了系统的全局渐近稳定性，在假设系统为周期系统的条件下得到了正周期解的存在唯一性和全局渐近稳定的充分条件。

Furthermore, when the system is a periodic system, sufficient conditions are obtained that guarantee the existence, uniqueness and global attractivity of the positive periodic solution by applying the Brouwer fixed theorem and the method of constructing Liapunov function.

利用比较原理给出了系统一致持久性的充分条件；当系统是周期系统时，应用Brouwer不动点原理和构造Liapunov函数的方法给出其存在惟一且全局吸引的ω-周期正解的充分条件，并通过实例验证了文中定理条件的可实现性。

The life cycle of a real estate is long, so it is important to the owner to take care of the functionality and value stability of the real estate throughout the life cycle.

由于房地产的生命周期很长，所以对于房地产商来说，注重房地产在其生命周期中的功能性和价值稳定性至关重要。

Normal temperature lixiviation had long production period but the produced wine had clean color and enjoyable taste.

常温浸提生产周期长，酒的色泽净雅、口感较好；加温浸提生产周期虽短，酒的色泽浓浊、口感较差。

Current mode control provides fast line and load transient response, as well as cycle-by-cycle overcurrent protection.

电流模式控制提供快速线性和负载瞬变响应及周期对周期过流保护。

Zigongdongdou, was used to investigate photoperiod effects on the development of terminal inflorescence of soybean, plant type and agronomic traits, with emphasis on the role of long-day in the formation of raceme. The plants were treated with short-day of 12h for 13 days to induce the initiation of terminal inflorescence, and then moved to 16h long-day treatment for 0, 1, 2, 3, 4 and 5 weeks, respectively. After LDT, plants were returned to SD condition.

为明确光周期特别是长日照对于短日照作物的生长发育及顶端花序发育的特殊重要作用，实验以光周期敏感的有限结荚习性晚熟品种自贡冬豆为材料，经过13天短日照处理(12小时)后，分别经过0、1、2、3、4、5周长日照处理，再在短日照处理下直到成熟，研究长日照对大豆顶端花序、株型及农艺性状的影响。

Photoperiod sensitivity can limit the geographicadaptation of Brassica napus to a great extent. For example, Q2, used as one parent in thisstudy which is one spring and photoperiod-sensitivity Brassica napus, only can be plantedin the long-day region as a summer crop for ensuring maturity and yield of seed.

光周期敏感性对春性甘蓝型油菜的种植地理适应性有较大的限制，例如光周期敏感性较强的油菜品种(如本试验的亲本Q2)只有作为夏季作物种植在长日照地区才能保证菜籽的正常成熟和产量。

Experimental results show that the refractive index modulation can reach about 0.010; and the depth of surface relief is low to about 0.7~12.4nm, which will be lower than 1nm in the gratings with 200~400nm period(according to the first-order and second-order DFB grating period of organic semiconductor lasers).

实验结果表明，折射率调制幅度较高，可以达到0.010左右；表面起伏很低，约0.7~12.4nm，在周期为200~400nm(对应于有机半导体激光器的一级和二级DFB光栅周期)的聚合物光栅中，表面起伏深度小于1nm。

The major contributions of this thesis include:(1) proposing a new kind of optimal feedback control, followed by its application to chaos targeting and stabilization of high period unstable periodic orbits ;(2) stabilization of unstable fixed point in chaotic systems using some kind of nonlinear feedback control, and giving sufficient condition for the existence of the controller as well as the synthesis procedure;(3) analyzing the robustness of optimal control in chaotic Lur'e systems under the help of H〓 control theory;(4) finally and most importantly, introducing a novel method of information storage based on discrete time chaotic systems as the application of chaos control, and systematically studying different schemata for implementation, providing a theoretic basis for the design of such new kind of information storage devices with large capacity.

本文的主要工作包括，提出一种新的最优反馈控制，并将之应用于混沌引导控制及混沌系统高周期不稳定周期轨道的镇定控制；针对不动点镇定控制的一类非线性反馈控制器，文中给出该类反馈控制存在的充分条件及设计步骤；文中还利用非线性H〓鲁棒控制理论对Lur'e混沌系统中的最优线性反馈控制进行鲁棒性分析；最后，也是最重要的，作为混沌控制的应用，文中提出一种基于离散时间混沌系统的信息存储方法，系统地分析、研究了实现这种信息存储的不同方案，为以后进行这种新型大容量存储器设计提供了一定的理论依据。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。