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In order to solve the problem of increased system weight and cost of current wireless power transfer (WPT) systems with ferrite, a Halbach-type coupler WPT system with flux-shielding function for linear motor has been proposed in this article. It is characterized by high transmitting efficiency, better shielding ability, and antioffset ability. First, the topology and working mechanism of the proposed coupler have been analyzed. Second, considering the coupling ability and magnetic flux density, the parameters of the proposed Halbach-type coupler have been optimized. Third, the prototype of the proposed system has been built and tested, compared with the current DD-type coupler WPT system. Fourth, the magnetic field shielding ability and antioffset ability of the proposed Halbach-type coupler and DD-type coupler have been analyzed, respectively. The experimental results have verified that the WPT system based on the Halbach-type coupler has more promising magnetic field shielding ability and better resistance to the $z$ -axis offset, compared with the WPT system based on the DD-type coupler. The efficiency of the WPT system based on the proposed Halbach coupler can achieve 80.5% and the maximum output power reaches 69.5 W at 11 mm.

A power system structure composed of a brushless DC motor and a cycloidal reducer for electric balanced vehicle has been proposed, and the temperature of important components in this structure would be discussed. The loss generated by the cycloid reducer is negligible, it’s only need to analyze the thermal field of motor. Since the temperature change will affect the material properties of the target motor, the electromagnetic and temperature fields, involved in the motor, are selected for coupling calculation to determine whether the final temperature distribution can meet the requirements of vehicle for use.

In this paper, the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation. The results from TWINSPAN and DCCA showed that: 1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region, the basic patterns characteristic of the different habitats are due to topographic factors, nutrients and moisture conditions; 2) The elevation affected the most basic differentiation of plant communities in the study area, indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area; 3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities; 4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities. In summary, under complicated mountainous topographic conditions, the habitat conditions for the communities differed very significantly, and the combination of elevation, soil moisture content, total nitrogen, slope aspect, and pH value influenced and controlled the formation of community distribution patterns in the study area.

The Study of the relationship between vegetation and environment have become important areas of vegetation ecology,different environmental factors of earth′s surface leading to the different distribution of plants and vegetation.Ili River Valley is a "U" shaped valley,which was known as one of Xinjiang′s most beautiful places.In this closed or semi-closed valley,there is kind of special "cold lake effect": In winter,as cold air accumulating in the bottom,the air in the valley forms a special "inversion layer" zone at altitude of 800—2000 m.In this special mountainous valley environment,the study of the vertical distribution patterns is of special significance.This study is set out to investigate the vertical distribution of the soil chemical properties,and to find out the the relationship between vegetation and the soils,which should provide important information for future vegetation restoration and reconstruction.Patterns of plant diversity and soil factors along the altitudinal gradient on northern slope of Ili River Valley were examined.Plant and environment characteristics were surveyed from the altitude of 1000 to 2200 m.There were a total of 155 vascular plants,133 herbages,18 shrubs,and 7 tree species in 44 sampled plots.The plant richness of vegetation types generally showed a special pattern along altitude,with a bimodal change of plant species number at 100m intervals of altitude.The two belts of higher plant richness were in transient zones between vegetation types,the first was in the transient zones from lower-mountain desert to forest,and the second in the transient zone from dry grass to coniferous forest.Soil nutrients and salt also showed a similar distribution pattern.Matching the change of richness of plant species to environmental factors along altitude and correlating these by PCA and relation analysis revealed that the environmental factors controlling species richness and its pattern were the combined effects of soil salt and nutrients.Water was more important at low altitude,and temperature was more important at high altitude.The effect of the inversion layer seems made the coniferous forest at high altitude had high plant species diversity.Species richness and soil total dissolved salt had a significant negative correlation(r =-0.343),and soil total salt also had a significant negative correlation with species richness(r =-0.341).Simpson index and soil pH showed a significant negative correlation(r =-0.465).Shannon-Wiener index and soil electrical conductivity showed a significant negative correlation(r =-0.367).Pielou evenness index and soil electrical conductivity showed a very significant negative correlation(r =-0.477).In a word,there was a strong negative correlation between plant diversity index and the index of soil salinity/alkalinity,which confirms the negative effect of soil salinity/alkalinity on plant or vegetation.This study of altitudinal pattern in Ili River valley provides an important scientific basis for protection and utilization of plant/vegetation resources in this region,should enrich the theory of vegetation-environment relationships,and is also helpful in the future practice of the restoration,reconstruction of the degraded vegetation cover.

Moisture is a primary limiting factor that affects plant growth. To determine the ideal amount of irrigation water for the growth of individual Populus bolleana Lauche, the major protective species around Qira oasis in southern edge of Taklimakan Desert in Xinjiang, China, we studied the moisture of soil layers with depth between 0-80 cm and the response of P. bolleana's water status such as moisture content, stomatal characteristics, leaf water potential, stem sapflow and stem diameter to different irrigation based on the field monitoring data. The results showed that the moisture content of soil layers with depth of 0-80 cm gradually increased with irrigation increasing, especially when irrigation was more than 30 liters. When irrigation was 30 and 40 liters, the daily leaf water potential presented an obvious unimodal trend: the predawn and midday leaf water potential increased significantly. Along with the irrigation increased from 10 to 40 liters, sapflow and stomatal conductance followed a trend of first decreases and then increases. When irrigation was 30 liters, the daily mean stem diameter and contraction of P. bolleana reached their peaks, indicating that irrigating more than 30 liters of water could improve the water status of P. bolleana and prevent it from drought stress. Thus, we concluded that the ideal irrigation amount for the normal growth of individual P. bolleana should be 30 liters per year.

Haloxylon ammodendron inhabits along the southeastern marginal zone of the Junggar Basin in Xinjiang. In this paper,the developmental processes of natural population of H.ammodendron are studied with the means of the dynamic life table.The results show that there are separately two peak stages of rapid drop of survival rate and high mortality rate of H.ammodendron seedlings.In which the mortality rate of H.ammodendron seedlings at the first stage from April 1 to May 1 is as high as 69.9%.At the latter stage from June 15 to July 15,the high mortality rate is caused by disadvantageous climatic conditions and eating by animals in the early growth season, but it is caused by the decrease of moisture content in shallow soil layer.The survival curves of H.ammodendron seedlings belong to the pattern of DeeveyⅢ,which indicates that the mortality rate of H.ammodendron plants is high at the early seedling stage,but the early seedling stage is a key period for the natural regeneration of H.ammodendron seedlings.The study results of dynamic life table at the seedling stage can provide the scientific basis for the natural regeneration of H.ammodendron seedlings and working out the management measures.

Deficient water resources in the arid lower Tarim River impose constraints to the growth and survival of planted seedlings of Tamarix ramosissima which is very needed in the rehabilitation of degraded desert riparian forest. The objective of this study was to compare root morphology, biomass production of the seedlings treated by two irrigation methods, i.e. side deep-ditch irrigation (SDDI) and above-ground irrigation (AGI), and three water levels, i.e. high water level (W1, 50L plant−1 once−1), medium water level (W2, 25L plant−1 once−1) and low water level (W3, 12.5L plant−1 once−1), to identify SDDI had a significant effect on promoting root growth. The results showed that SDDI significantly increased fine root (0.5 mm < d < 2 mm) length, fine root surface area, coarse root (d > 2 mm) biomass, below and above-ground biomasses compared with AGI. The vertical growth rate under SDDI and W1 was significantly higher than that in other treatments. SDDI caused an increase in specific root length (SRL) of the fine root at high and medium water levels. Our results suggest that SDDI caused rapid and great root elongation and root biomass production of Tamarix ramosissima seedlings, which benefited the seedlings survival in the early growing stage.

In some applications, travelling wave induction heating (TWIH) could make this kind of heating more profitable in comparison with other known systems. In this paper a three-dimensional single-coil model of transverse flux induction heating inductors (TFIH) and TWIH has been simulated by ANSYS. The different eddy current densities in the metal strip also have been analyzed when the circle loop lies in the internal or external of the projector.