查询词典 decrease in population

This paper deduces a theoretical population model in a urban system under a hypothetical condition of zero population growth,and analyses the population dynamics for the model.

本文推演了城市系统中在人口零增长假设条件下的人口迁移理论模型；对该模型的人口动力学特征进行了分析，并以仅由二个城市构成的最简单城市系统人口迁移为特例，研究了该模型的实际解释

The important elements of population dynamics were the population age structure,the pregnant rate,the reproductive indices and the population number of other species(little Chinese jird,northern three-toed jerboa and striped hamster).

结论影响种群数量变动的主要因素有种群年龄组成中幼年组的百分比、怀孕率、繁殖指数以及该地区子午沙鼠、三趾跳鼠和黑线仓鼠的数量。

In the study on the fern population structure, we through the analysis of the variation in height structure, leafstalk diameter structure and age structure in various forest communities, found the rule of variation of population, and discussed the reasons of variation of population structure, and explored the suitable habitat of various forest ferns.

在蕨类植物种群结构的研究中，我们通过对不同群落中蕨类植物种群高度结构、叶柄直径结构和年龄结构的研究，发现种群结构变化的规律，找出种群结构变化的原因，探索出各种蕨类植物种群的适生生境。

More physical mass requires more resources needed, meaning ever more material, energy and/or technical progress – or just more " Lebensraum "; hence the effects of severe over-population will arise even with steady or even declining population numbers! Therefore, the extremely mobile population of the U.S.A.

越多的有形形体，就需要越多的资源，也就意味着更多的物质，能量和/或技术进步—和更多的生存空间；因此，人口大量的过剩会影响社会的稳定，甚至人口数量的下降。

On the other hand,there has been so far no mapping method and software that can be used to map dominant-recessive markers obtained from F2 population of lepidopteran species.To resolve this problem,two-point and three-point maximum likelihood methods for mapping dominant-recessive markers using F2 population of this type of species were developed in this paper.At,the same time:we also gave a general method for constructing the gene linkage map of this type of species using F2 population.

另外，目前还没有任何方法和软件可以用杂交F2群体来作图鳞翅目类昆虫，如家蚕等连锁图谱，为了解决这一问题，本文发展了用F2群体作图这类昆虫连锁图谱的两点和三点极大似然法，同时还给出了大群体作图形态基因连锁图谱的一般方法。

Those theories include:Malthusianism,the pessimistic population economic theory,the theory of long term stagnation,the optimistic population economic theory,low level equilibrium trap theory,critical minimum effort topic,optimum population theory,sustainable develo...

在此基础上，对人口经济理论演进的特点进行了总结：研究内容与不同时代所面临的主要社会经济问题紧密相关；研究领域日益宽泛；研究视野从发达国家扩展到发展中国家乃至全球范围；研究方法和研究思路的进步与完善。

Note that a very low county population can result in a misleadingly high ratio calculation (eg Mono county's 23: 100,000 population ratio is based on only 3 acupuncturists and less than 13,000 population).

请注意一个非常低的县人口可能导致误导性高的比率计算，例如（单县的23：10万人口的比率是基于只有3针灸，不到13，000人）。

The total population of a district in Beijing is predicted in this paper using Logistic Model.The ratio of population is also calculated using the mortality table.Furthermore,the labour resource and the number of old-age population are predicted combining Logistic Model with the mortality table,and relevant policies are suggested based on the above analysis.

本文用Logistic模型对北京某区的总人口进行了预测，用生命表滚动预测模型推算出了该区的人口结构比重，并利用这两个模型相结合的混合预测方法，对该区的劳动力资源和老年人口数进行了预测和分析，并在此基础上提出了相关的建议。

Set up and improve the comperhensive population management, the system of better natal and pre-natal care and better upboring, maintaining the low natality level, control the population and promote the quality of population.

建立完善的人口综合管理与优生优育体系，稳定低生育水平，控制人口总量，提高人口素质。

By 2020, China's aging population will make the working population and the ratio of non-working population, the world's worst, even worse than Japan.

到2020年，中国人口老龄化会使工作人口与不工作人口的比率成为世界上最糟糕的，比日本更甚。

Chimborazo and Cotopaxi, took me by the hand.

越过琴博腊索山和科托帕克西山。

This car is in a good condition.

这辆车的状况很好。