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Line-start permanent magnet synchronous motor with composite rotor is a new type of permanent magnet synchronous motor, which uses eddy currents induced in solid rotor and copper bars to achieve self- starting capability. In order to research the demagnetization of permanent magnets under three-phase short circuit and out-of-step fault, the finite element model considering saturation, eddy currents and other factors are established. The effects of moment of mutation, initial load torque and initial moment of inertia are studied. The rules of demagnetization point of permanent magnet in two kinds of faults are summarized.

China southwest region has suffered from three years of severe drought in the dry season from 2010 to 2012, with devastating impacts on agricultural productions. Previous agricultural cropping patterns were adjusted to adapt to drought. How to find evidences of agricultural adaption to drought? Here, we showed agriculture adaptation to drought stress according to the changes of vegetation greenness, a proxy for agricultural drought conditions. Based on weather station observation from 1991 to April 2012, we concluded that the study area suffered from extreme drought in the dry reason of both 2010 and 2012. Notably, based on satellite monitoring of agricultural vegetation greenness in ten years, the results showed that drought intensity in 2010 and 2012 was almost equivalent (−66.85% in 2010 and −65.87% in 2012) and drought extension in 2012 was 14.52%, which was less than the half of 36.46% in 2010. Overall, the evidences of agricultural adaption to drought were obvious.

Sudden cooling during the crop growing phase seriously impacts crop growth. Crop vulnerability to low temperature stress is affected both by crop growing condition and the lowest environmental temperature. In this study taking winter wheat in Huang-Huai-Hai Plain of China as an example, vulnerability index to low temperature stress was assessed based on time series satellite data in nearly ten years. Growth sensitivity of wheat-frost was quantified by vegetation index change between tillering stage before winter and shooting stage in the next year. Exposure index of wheat-frost was defined as lowest land surface temperature during critical growth period. Cluster analysis of crop mean vulnerability index showed that high vulnerability of wheat-frost located in central and northern of Hebei Province in nearly 10 years. The result will help to prevent frost damage of winter wheat.

Drought and frost are two main natural disasters to winter wheat in China northern plain. Based on MODIS data in the last ten years, sensitive analysis of vegetation indices to these two disasters is presented in this paper. The result showed that EVI, NDIIb6 and NDIIb7 are suite for frost damage assessment. Although the winter wheat suffered serious drought in this region, the stress characteristics of winter wheat responded by both greenness change indices and water content change indices are not obvious.

System isolation, inconsistent information, verifies frequent and so on are the problems facing with of the campus network construction. In order to solve the problems above, we integrated B / S architecture applications with the Single sign-on (SSO) system. A unified personnel database has been established using LDAP server, and creates dynamic groups to manage elements of the database. CAS and Form technology were used to achieve the integration of internal campus network applications and other black-box system with SSO.

In this paper, we proposed an improved delay feedback control method (IDFC) for a chaotic neural network. In the method, a delay feedback control signal is added into the term of the refractoriness of the chaotic neuron to resist the chaos in the chaotic neural network. The computer experiments show that the output sequence of the controlled chaotic neural network become periodic. The controlling chaos in a chaotic neural network is therefore implemented. When control parameters K and tau are taken as 1.3 and 1 respectively, the outputs of the network is periodic-16