人为变量

After a detailed analysis of the forces in subway train's running, the dynamics mathematical model of subway train is constructed; the eventbased control technology is adopted to solve the controlling of subway, the velocity and acceleration function with respect to the distance are deduced by introducing the action reference variable in the control problem which the object is to minimize the running time. The running scheme can be programmed in realtime, the delay caused by uncertain events is avoided. So it offers a new way for the metro research.

分析了地铁列车运行过程中的受力情况，建立了地铁列车的力学模型；将基于事件的控制技术应用到地铁列车的控制中，通过引入运动参考变量，求出在以站间最小运行时间为最终目标的列车控制中，列车速度、加速度等关于列车运行距离的函数表达式，从而可以根据列车走行距离来实时调整和规划地铁的运行规律，避免人为因素或不确定性因素导致的列车运行晚点，为研究地铁列车的规划提供了一种新的方法。

We can infer that contrived factor is distinct contribution from the four extracted prime components. The contributing rate in the first prime component is 54.4%.

从提取出的四个主成分看出，人为作用对荒漠化有显著的贡献，第一主成分中变量的贡献率是54.4％。

Effect on birds community:Through the analysis of the correlation between the birds amount and frequency in the 9 parks and the 12 structure indexes of the parks,we reach the conclusion that Passer rutilans and Turdus merula are mostly effected by the area of the habitat, while Carduelis spinus,Parus venustulus,Aegithalos concinnus,Anthus hodgson,Paradoxornis webbianus and Trachybaptus ruficollis are mostly effected by humanlnterference.

对鸟类的影响：通过对市区9个公园的生境破碎化相关的结构、连通性、隔离度、人为干扰等12个特征变量与鸟类数量和出现频率的相关分析，发现常见鸟类中，麻雀和乌鸫对生境面积存在显着的相关关系；而黄雀、黄腹山雀、红头长尾山雀、树鹨、棕头雅雀以及小鸊鷉受到人为干扰的影响较为明显；白头鹎和珠颈斑鸠的数量与生境斑块的形状指数呈负相关；麻雀的数量随着斑块中灌木层密度的增加而上升；白鹡鸰随着乔覆盖度的增加而减少。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。