Test Study On Property Of The Parallel Composite Isolation Bearings

Inner Mongolia grassland is the biggest natural grassland pasture and important ecological shelter. As the climate change sensitive area and the fragile district of ecology, suffering the destruction of climate and human beings, the grassland vegetation cover have decreased.It leads to that the grassland degeneration, drought and flood, rat infestations, sandstorm and so on happen frequently.Our country suffers magnificent economic loss.Therefore, it’s particularly important to research the relationship between the grassland vegetation’s change in time and space and correlation factor.These researcher use the remote sensing technology to analyze the relationship between the vegetation index and climate factor in the past decade in Inner Mongolia grassland Researching the time-space distribution regularity of Inner Mongolia grassland coverage via making the NDVI time serious;and using EMD wavelet denoising model, Combining the ground sample materials, from subclass level to analyze the time-space distribution of various vegetation.The main research in this article indicate:(1) The annual average temperature generally changes little in Wulate, Xinlin Hot and Evenk;the precipitation of Xilin Hot and Evenk Banner have decreased annually, Which present fluctuant uptrend in Wulate Zhongqi;the middle-west of Inner Mongolia response to rainfall in higher level than the east area.The precipitation concentrate in July and August.After90’s, the interval of precipitation shorten, Flood disaster happens frequently in east area.Various climate factors and NDVI relativity aren’t notable;Xilin Hot and Urad Middle Banner precipitation present positive correlation with NDVI, the correlation coefficients are0.455(via0.05significance test) and0.309;The wind speed and sunlight in Wulate Middle Banner present significant negative correlation with NDVI, the correlation coefficients are-0.455and-0.418(both via0.05significance test)(2) Walate dominated by desert vegetation of temperate grasslands changes little in monthly NDVI values.However, that shift greater in Xinlin Hot which is dominated by plateau grasssland.When it goes to Evenk, it is even greater than before, which is almost consist of forest and grassland and with leaves falling in winter. (3) Recent10years, the vegetation in Walate Zhongqi, performed the trend which was recovery after degeneration;The same situation appeared in XilinHot, the worst condition was in2000and it became better afterwards.In addition,83.968%of the grassland recovered during2000-2007.When it goes to Evenk, it presented like this order:degeneration, recovery and serious degenerition.The NDVI value increasing sharply after2000and the worst year is2007.(4) From1998to2008, the NDVI values presented multi-step increase trend in the growing season from west to east in Inner Mongolia grassland.There was a widespread and intensive vegetation degradation after1999and the worst condition arised in2000. A higher degree of recovery through out2001-2002.Then it was keeping gently between2002and2003, decreased in2004and2006and began to recover after2007.More than30%of degraded grassland was started to recover in varying degrees because the relevant protection policies was formulated in2000and we can conclude that the overgraze and factitious damage were the leading factors.(5) The EMD-based extraction of signal demodulation could remove the noise and error message, and better obtain the growth tendency of different kinds of vegetation. In Wulate area southern foot of the Yinshan mountain, and Yellow River irritation area had nice vegetation cover between1999-2007, the vegetation in most areas got improvement; some kinds of vegetation in northwestern and northern of the gobi desert area got improvement, the average value of NDVI was still lower than0.1and presented to be serious desertification;The middle area was constant oscillation, yearly change greatly, and hadn’t got notable improvement;In Wulate Middle banner, the annual average NDVI value rose every year.With the growth tendency curve of10kinds of vegetation, we found the slope of the sixth kind vegetation (main pasture grass) was negative and had attenuaton tendency.This suggest that may relate to the human factor such as overgraze.