环形

Compared with the FFT-based computation to CAF, the presented method can scan the target only in certain circular sector instead of the whole ambiguity plane, which may decrease the computational load.

与基于FFT计算互模糊函数的方法相比，采用这种方法的优点是在检测目标时可以只扫描某个环形扇区而不用计算整个模糊平面，减小了计算量；另外，由于在计算互模糊函数时极角和极径的取样间隔可以任意选择，突破了时域采样间隔的限制，可在时延和频移上均得到高精度估计。

1Niche construction can lead to stable coexistence of diverse genotypes in spatially structured population, which supports a stable polymorphism even without heterozygote superiority.(2)With habitat deterioration, niche construction accelerates the formation of steady polymorphism and hence impedes the harmful influences of environment on the population, which might embody a life-history strategy of organism under the unfavorable environment.(3)Niche construction results in the coexistence with alternative polymorphism through genotype-environment feedback and limited gene flow.(4)The niche-constructing organism is an active force to alter its environment and hence the direction of natural selection in order to better survival.(5)Spatial dynamics and distribution pattern of metapopulation are profoundly influenced by time-lagged niche construction.(6)Metapopulation size can reach a fixed level in the recency effect and equal weighting of time lag but is statistical stability in primacy effect, which implies the primacy effect is most remarkable.(7)The increment in the relative weightingof each generation\' niche construction and the length of time lag are significant factors for system destabilization.(8)Moderate capacity of positive niche construction benefits the metapopulation persistence.(9)The narrowing of niche breadth can decrease the metapopulation size and thereby increase the extinction risk.(10)The coupled function of time lag and niche construction make the system oscillation and generate the spiral wave, spiral-broken and circular wave in heterogeneous habitat.The spatial distributions of metapopulation and resource content are complementary due to a phase lag of their both frequencies.(12)Metapopulation persistence with niche construction depends not only on the balance between colonization and extinction, but also on the balance between the ability of niche construction and natural dissipation of habitat.(13)Metapopula-tion can survive under certain condition when the percent of suitable patches in habitat is lower than the ration of extinction to colonization.(14)Two thresholds exist in the process of transition of habitat quality dynamics from unsuitable to suitable, which include the intensity of niche construction and the initial condition of system.(15)Metapopulation size is positive correlated with the ability of positive niche construction, which means that organism or population who has strongly positive influences on their environment plays an important role to maintain the available habitat.

通过上述几个方面的研究，主要得出以下15条结论：(1)生态位构建可使空间结构种群，甚至是在没有杂合子优势的条件下，形成多种可能的稳定基因型分布模式；(2)随着环境的破坏与恶化，种群的生态位构建作用加速其较早形成稳定多态以阻碍环境对种群的不利影响，解释了有机体在不利环境下的一种生活史对策；(3)生态位构建作用通过基因型—环境反馈机制及有限的基因交流导致基因型多态的稳定共存；(4)有机体的生态位构建作用是一种积极的动力改变环境进而改变其自然选择的方向；(5)生态位构建的时滞作用对集合种群动态和空间分布产生深刻影响；(6)集合种群大小在时滞的崭新效应和等权重效应下达到一固定值，而在首位效应下达到统计稳定，表明首位效应的影响最显著；(7)首位效应下生态位构建相对权重的增量和时滞的长度是影响系统不稳定性动态的关键因素；(8)适中的生态位构建强度有利于集合种群的续存；(9)生态位宽度变窄会减少集合种群的数量从而增加其灭绝风险；(10)时滞和生态位构建的双重作用使系统产生周期振荡，并在异质性环境中产生稳定的螺旋波，破碎的螺旋波和环形波三种分布模式；(11)集合种群与资源含量的空间分布因为相滞而互补；(12)具有生态位构建的集合种群续存不仅取决于侵占率与灭绝率之间的平衡，而且依赖于生态位构建能力同其生境的自然消耗速率之间的妥协；(13)当生境中适合侵占的斑块比例小于其侵占率与灭绝率之比时，生态位构建作用促使集合种群在一定条件下续存：(14)生境斑块的状态从不适合到适合转变过程中存在生态位构建强度和系统初始条件这两个阈值；(15)集合种群的大小同正生态位构建能力正相关，意味着对环境具有较强正作用的有机体对维持有效生境起积极作用。

We didn't want to inconvenience them, so we had a circular drive.

我们不想给他们的父母带来不便，所以我们有环形车。

In the experiments, the optical output power of the master laser is injected into the slave laser via a circulator.

实验中通过一个环形器，将主激光器的输出光注入到从激光器。

Cirque form is the main modelling of this kind of jade article.

圆环形是这种玉器的主要造型。

If the two terminals of a path coincide, the path is a closed path and is called a circuit.

如果一条路线的两个端点相交，那么它是一个封闭的路线，称之为回路或环形。

In geometry a polygon is traditionally aplane figure that is bounded by a closed path or circuit, composed of a finite sequence of straight line segments.

在几何学中， polygon是一个传统的平面图形由封闭路径及环形，由有限的直线规律地构成。

Bellows is corrugated ring was closed circle of the tube-shaped shell, between the wave and the wave formed by a series of corrugated rings.

环形波纹管是波纹呈闭合圆环状的管形壳体，波与波之间由圆环波纹串联而成。

About the time the Tank Stream estuary disappeared under Circular Quay, maritime interest turned to Cockle Bay, or Darling Harbour as it is now known.

当贮水池河的河口在环形码头的下方渐渐消失，海事活动的中心转移到了可可湾，也就是现在为人们所知的达令港。

The relationship between stiffness coefficient and prestress degree of ring section is established by substitution prestress degree based on stress ratio for crack factor from China design code.

由于高耸结构在外荷载作用下处于压弯状态，因此本文基于应力比定义预应力度，以应力比预应力度替代规范中的弯矩开裂系数，建立了环形截面刚度系数和预应力度的关系。

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。