查询词典 proportion of births to population

The accurate prediction of the population in Hunan Province has a great theoretical and practical significance. Using auto-regressive model, Logistic model, as well as the Malthusian model of population, make a scientific prediction to the population in Hunan Province in 2009-2020, and put forward some suggestions on control population capacity.

文章采用自回归模型、马尔萨斯人口模型以及Logistic模型等多种数学分析方法，对湖南省2009-2020年的人口数量做出了科学预测，为湖南省在新的历史机遇期制定相关社会经济发展战略与规划提供相应的依据。

It is dedicated to education and research focusing on a wide diversity of research areas, including the quantitative population ecology of plants and small mammals, terrestrial plant community ecology, grassland biodiversity and restoration ecology, plant fungal pathogen dynamics and population biology, successional changes in terrestrial insect communities, terrestrial ecosystem ecology, the remote sensing of natural resources, life history theory, molecular evolution in vascular plants, evolutionary and theoretical population genetics, theoretical ecology, and limnology and aquatic ecology, basic biology of insects, Ecophysiology; paleobotany; population genetics, evolution of plants and fungi.

其主要致力于生态学和进化生物学的教育和研究，主要学科领域包括植物和小型哺乳动物种群生态学、陆地植物群落生态学、牧草生物多样性和恢复生态学、植物真菌病原动力学和种群生物学、陆地昆虫群落连续改变、陆地生态系统生态学、自然资源遥感、生命史理论、维管束植物分子进化、进化和理论种群遗传学、理论生态学、湖沼学和水生动物生态学、基础昆虫生物学、生态生理学、古植物学、种群遗传学、植物和真菌的进化等。

Spatial population distribution characteristics in Xinjiang show that the population in the West is more than that in the East, the population in the North is more than that in the South; The population in the oases in hill pediment alluvial fan are the most.

新疆人口分布的空间变化规律总体分布趋势为西密东疏，北多南少；山区和盆地相交的山前冲洪积扇缘绿洲地带最多，盆地中心及其盆地周围山区人烟稀少。

Wang Kai Global Times special correspondent reports, according to Africa News reported on November 19, 18, United Nations Population Fund issued a "State of World Population 2009 report," the theme of this year's report is the " population explosion and climate change", mainly from population growth ...

环球时报特约记者王凯报道据非洲新闻网11月19日报道，联合国人口基金18日发布了《2009 年世界人口状况报告》，今年报告的主题是"人口爆炸与气候变化"，主要是从人口增长。。。

The Markov forecast model, time series method (triple exponential smoothing method and a combined of triple exponential smoothing method and Markov model) and stepwise regression forecast method were choosed, and the basic principles and processes of the three models were analyzed and compared. Based on above, the three methods were used to predict population dynamic of Cricetulus barabansis and Meriones unguiculatus. The characteristic, accuracy and applicability of three methods were analysed and compared. The results showed that,(1) Markov model belongs to a middle-long time forecast model, and the result was interval forecast, but it reached the requirement of forecasting the harmful population dynamic of rodents. Through the forecasted population dynamic of Cricetulus barabansis and Meriones unguiculatus in 2004, the results were accurate; this meant that Markov model was a good forecast model to Cricetulus barabansis and Meriones unguiculatus population.

选择马尔可夫链预测模型、时间序列分析法(三次指数平滑法、三次指数平滑法和马尔可夫链预测模型的组合预测法)和逐步回归预测法，对这三种模型的基本原理、模型的构建过程进行对比分析，在此基础上用此三种方法预测了黑线仓鼠和长爪沙鼠的种群数量，并对三种方法的特点、预测的准确度和适用范围进行了比较分析，结果表明：(1)马尔可夫链预测模型属于中长期预测，预测的结果为区间预测，但对于害鼠种群数量的预测来说已经达到要求，通过对2004年黑线仓鼠和长爪沙鼠种群数量的预测，预测的结果都比较准确，这说明对于预测黑线仓鼠和长爪沙鼠种群的数量动态，马尔可夫链模型是比较好的模型。

In the 2A1 distorted trigonal bipyramid structure ,the single non equivalent Ga atom has the population of 4s 4p ,while the two equivalent Ga atoms have the population of 4s 4p .this compares with a Ga population of 4s 4p in the undistorted D3h structure ,hence the jahn-teller distortion causes depletion of the charge density on the 4s orbital of the non-equivalent Ga atom, and enhancement of charge density on the 4s orbital for the two equivalent atoms .an opposite trend is observed for the 4p orbitals of these Ga atoms .the P population for the two equivalent atoms is 3s 3p .the populations of the other 2B1 state with the edge-capped tetrahedral structure are similar with the exception that all three Ga atoms have similar but not identical populations .

在2A1被变形的三角bipyramid结构，唯一非等效Ga原子有4s 4p的人口，而二个等效Ga原子在未变形的D3h结构有4s 4p 。this的人口和4s相比4p的Ga人口，因此jahn出纳畸变在non-equivalent Ga原子的4s轨道导致电荷密度的取尽，并且电荷密度的改进在4s轨道为二个等效原子。an在趋向对面对这些Ga原子4p轨道被观察。the人口为二个等效原子是另一个2B1状态3s 3p 。the人口与边缘加盖的四面体结构是相似的P 除之外全部三个Ga原子有相似，但不相同人口。

The results showed that the number of young individuals was larger than that of middle aged and old individuals in the B. platyphylla population. The population had one peak of mortality in size class Ⅴ. The survival curve of the population appeared to be the Deevey-Ⅱ type. The population was a rise type at present.

结果表明：白桦种群幼年个体丰富，中老年个体相对较少，种群在第V龄级出现死亡高峰，种群存活曲线属于Deevey-Ⅱ型，白桦种群目前表现为增长型种群。

Thunbergii trees were established, and the sun survivorship curves were drawn with field data. The results showed that in the three plots, the height and basal diameter growth of regenerated young P. thunbergii trees had exponential, linear, and quadratic functional relations with age and the age structure was of spindle, discrete, and pyramid types, respectively. Most of the regenerated young trees were distrbuted at 0.3-1.2 m from their nearest standing trees, and the individuals of the young trees decreased near to or far from the nearest standing trees. Inplots Ⅰ and Ⅲ, the expected average life of regenerated young P. thunbergii trees had a decreasing trend with their increasing age, and the survival number of the population also decreased with increasing population age. The survivorship craves of regenerated young P. thunbergii trees in the two plots approximated to the type of Deevey Ⅱ, indicating that the young P. thunbergii populations in the plots were at stable development stage. The population structure of regenerated young P. thunbergii trees in plot Ⅱ was lesser integral, suggesting that the population was of declining types being related to human disturbance, slope and other environmental factors.

结果表明：(1) 3个样地中幼龄植株高生长、基径生长与年龄均分别呈指数函数、直线和二次函数关系；(2) 3个样地黑松幼龄植株年龄结构存在着明显差异，分别表现为纺锤形、残缺型和金字塔型；(3)幼龄植株主要集中分布在距最近立木0.3~1.2m，离立木越近或越远幼龄植株均逐渐减少；(4)对样地Ⅰ和样地Ⅲ黑松幼龄植株生命表和存活曲线的分析表明，随年龄的增加，黑松幼龄植株生命期望值基本上呈递减趋势，黑松幼龄植株种群存活数也随着年龄的增加而降低；样地Ⅰ和样地Ⅲ黑松幼龄植株种群存活曲线近似于Deevey Ⅱ型，表明2个样地黑松幼龄植株种群处于稳定发展阶段；(5)样地Ⅱ幼龄植株种群结构很不完整，表明该种群属于衰退型，与人为干扰及坡度等有关。

Based on the data of the fourth population census in Fujian province,we drew population age pyramides model,analysed the Change of population age structure in every period and predicated the population of the 2000nd year by an age-transfering way.

根据福建省4次人口普查资料绘制人口年龄金字塔，分析各个时期的人口年龄结构变化，并根据第四次人口普查资料，采用人口年龄移算法预测2000年人口。

Population viability analysis has the important value for the conservation and management of the small population. This article introduced the progress of the population viability analysis on birds and discussed the population dynamic in 100 years of the Cabot's tragopan in Wuyanling National Nature Reserve.

种群生存力分析对小种群的保护和管理具有重要的价值，文中介绍了种群生存力分析在鸟类学研究中的进展，探讨了在研究数据不完备的情况下进行种群生存力分析的风险性。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。