Research on Coupling Relationship between Social Economy and Ecological Environment in Jinghe County of Aiby Lake Basin,Xinjiang

Based on the theory of sustainable development,using the theory and method of coupling relationship,the main city of Aiby Lake basin——Jinghe County in Xinjiang is selected. Based on the analyses of natural condition,population growth,land use type and ecological environment,the comprehensive evaluation index systems of socio-economic development level and eco-environment quality in Jinghe County are constructed. Using principal component analysis,a comprehensive evaluation of socio-economic development level and ecological environment quality in Jinghe County is conducted by combining with Excel. Their coupling relationship is studied,and quantitative coordination degree between social economy and ecological environment in Jinghe County is obtained. The results show that in recent 50 years,socio-economic development level in Jinghe County is rising,but the ecological environment quality is falling. Their coupling degree C changes during [- 1. 260, ＋ 0. 482],in other words,their coupling relationship is changing between ＂ reluctant coordination＂ and ＂ not coordination＂. After entering into the 21 stcentury,their coupling relationship is basically ＂ reluctant coordination＂. On this basis,the existing problems in the process of sustainable development in Jinghe County are analyzed,and the suggestions about promoting coordinated development between social economy and ecological environment are put forward.

Performance Degradation of the Repeated Recycled Aggregate Concrete with 70% Replacement of Three-generation Recycled Coarse Aggregate

The feasibility of using different generations recycled coarse aggregate（RCA） on structural concrete was fully evaluated by studying the performance of the recycled coarse aggregates and their corresponding concretes, the different generations of RCA were recycled by following the repeated mode of ‘concrete-waste concrete-coarse aggregate-concrete＇. Moreover, the focus was on ‘three generations＇ of repeated RCAs, the RCA was produced by crushing and regenerating the artificial accelerated degraded concrete, the process was designed to follow the nature degradation of the concrete with a coupling action of accelerated carbonation and bending load. The properties of x-generation（x=1, 2 or 3） of repeated RCA were systematically investigated and the compressive and splitting tensile strengths of relating structural concretes（with 70% replacement of x-generation of RCA） were studied accordingly. The results show a competent compressive and splitting tensile strength of 30 MPa at 28 th day of structural concretes with all generations of repeated RAC. And the gradual degraded performance of the repeated RCAs was observed with an increased numbers of repetition（1〉2〉3 generations）, the overall performances of all repeated RCAs fulfill the Class Ⅲ according to Chinese Standards GB25177-2010. Our gained insight demonstrates a feasibility of using at least 3 generations of repeated RCA for the production of normal structural concrete.

Capturing uncertainties of the underwater acoustic environment based on an ocean-acoustic coupled model

Considering the uncertain effects of temporal and spatial changes in the marine en- vironment on the underwater acoustic environment, we established an ocean-acoustic coupled numerical model and performed a parallel calculation. This model incorporated acoustic calcu- lations into the dynamic ocean, thereby achieving a dynamic forecasting and assessment of the acoustic environment. Furthermore, we adopted the ensemble prediction method to predict the vertical structure of temperature in a classic cross-section, the sound speed of the cross-section of the investigated sea area, and transmission losses. We gave the prediction errors of the sound speed profile as well as the 90% probability interval of transmission losses and the uncertainty histograms of the sound speeds, transmission losses, and sonar ranges at different depths and frequencies. The results reflected the influence of marine temporal and spacial variations on the uncertainties of the underwater acoustic environment, and the results also quantified the uncertainties of the underwater acoustic environment parameters. The experimental results indicate that the method used in this study is able to delineate and quantify the uncertainties of the underwater acoustic environment caused by marine dynamic changes.