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A reasonable prediction of low flow years in a region in the future so as to make deployment in advance is related to the stability of the region. This paper established conventional GM (1,1) model and improved GM (1,1) model based on grey system theory to predict low flow years in the upstream of Zhang River which has gray characteristics so as to avoid risks, improve spatial and temporal allocation of water resources and promote sustainable development of the basin. The research shows that improved GM (1,1) model which can improve the smoothness of the original data series provides a more accurate prediction than conventional GM (1,1) model by using the example of Zhuozhang River tributary in the Upstream of Zhang River.

The temperature field distribution is a most important part we pay close attention to when gas insulated bus is designed. In this paper, finite element method is employed to calculate the temperature rise of gas insulated bus based on fluid governing equation and heat conduction equation. The problem of convection heat transfer between fluid and solid is solved by multiple species transport technique which provides convenience for the calculation of convection heat transfer coefficient. The solution region includes SF6 gas, ambient air, conduct and tank whose electrical and thermal properties are dependent of temperature. Analysis result illustrates that the thermal field distribution is symmetrical, the lowest temperature is at the bottom of the tank, while the highest temperature is on the top of the conductor.

Under the background of global climate warming, the low carbon economy has become the focus of international attention. Some developed countries construct the low carbon trade barriers and implement trade protection on the grounds of environmental protection. This makes the cost of China’s agricultural products export increased, the scale of China’s agricultural products export reduced and the exertion of the traditional comparative advantage of China’s agricultural products inhibited, but at the same time promotes the development of China’s low carbon agriculture. The paper puts forward some countermeasures to cope with the low carbon trade barriers from the point of view of government and enterprises.

Foods and agricultural products safety problems caused by the packaging materials have attracted extensive attention all over the world and some developed countries take it as a technical trade measure to increase the threshold of foods and agricultural products import, which brings about great negative impact to the export countries. Based on the analysis of the packaging material barriers faced by foods and agricultural products export of China, this paper will put forward some countermeasures to break through the packaging material barriers of foreign countries.

mage enhancement has applied widely in biomedical, nondestructive testing, satellite remote sensing and other fields. Especially for the low contrast radiographic images, usually there are some disadvantages for a radiographic image such as the local area image does not show a striking contrast. In order to improve the clearness of low contrast radiographic images, in this paper we combined global adaptive equalization with local dynamic enhancement,then we simulate this enhancement algorithm. The new method will not only effectively increase the global contrast of low contrast radiographic images, but also intensify local details. Because the new algorithms contrast enhancement coefficient function can be adjusted dynamically and locally, the new algorithms are not only adaptive to the process of radiographic images but also having great reference value to the other grayscale images.

This paper presents a model based on analysis on interactive users search needs. This model changes from the analysis on user's behavior to the one on search content, which reduces to violate users privacy, and enables users to actively participate in determining the needs of search from the client end in the search engine, in addition to establishment of search demand model based on a large number of user feedback data mining in the search engine subsystem, as a result of higher search precision with less client spending and higher user s participation.

Yeast two-hybrid system was used to investigate the estrogenic activities of 13 kinds of representative endocrine disrupting chemicals (EDCs) and their combinary effects. Results show that the order of estrogenic potencies for these chemicals is: 17α-ethynylestradiol>diethylstilbestrol >17β-estradiol>estrone>estriol>branchedp-nonylphenol>4-t-octylphenol>bisphenol A>diethyl phthalate>4-n-nonylphenol>di-(2-ethylhexyl) phthalate>dibutyl phthalate>dimethyl phthalate. The mixture effects of multiple EDCs were compared to those obtained from individual chemicals, using the model of concentration addition. Results reveal that the estrogenicities of multicomponent mixtures of more than three (including three) of EDCs follow antagonistic effects, while there is no definite conclusion for binary systems. The less than additive effects were also confirmed in the spiked experiments conducted in the extracts of real water samples.

Aluminum alloy welding wire ER5356 was welded on galvanized steel plate by Pulsed DE-MIG. The best welding seam morphology was got by adjusting Pulsed DE-MIG welding parameters. It indicated that welding-brazing of aluminum-galvanized steel dissimilar metals were achieved by Pulsed DE-MIG. SEM and EDS were adopted to observe and analyze the interface microstructure of welding joints. The results indicated that two intermetallic compounds layers of Fe2Al5 and FeAl3 formed along the interface of aluminum-steel. And models of interface reaction of aluminum-steel dissimilar metals were put forward.

Aligned PHBV/PEG ultrafine fibers are fabricated for potential applications in tissue repair. In this paper we find that the optimum spinning parameters to prepare aligned PHBV/PEG fibers is as follows: the concentration of 8wt%, voltage at 10kv, receiving distance at 18cm, the boost speed at 0.8ml/h and the best linear velocity of the rotating drum at 9.5m/s. The content of PEG is less than 50%. In addition, we investigate the interaction between PHBV and PEG in its entirety; we also discuss the surface morphology of the blends, compatibility, thermal decomposition and crystallization behavior by the help of different test methods.

In this study the toxicity of malachite green (MG) to aquatic plants (rice seeds) and impact by Aldrich humic acid (HA, used as model dissolved organic matter) were investigated with the germination rate of rice seeds. Results showed that germination rate was decreased from 77% to 1% with the increasing concentration of MG (0-2000 mg L-1), and the obvious dose-response relationship was observed. At the same time, the germination rate was improved from 33% to 50% after the addition of HA (1-500 mg L-1) at the fixed concentration of MG (1000 mg L-1).

Water and bottom sediment samples were taken from the Zhenjiang section of the lower reach of Yangtze River, China during the autumn of 2011, aimed to study the pollution levels of six kinds of phthalate acid esters (PAEs). Water samples were prepared by solid-phase extraction (SPE) and analyzed by gas chromatography-mass spectrometry (GC–MS), with spiked recoveries ranging from 33.5% to 121.0%. Sediment samples were pretreated using ultrasonic-assisted organic solvent extraction, with recoveries varying from 43.7% to 107.6%. Results showed that the concentration levels of PAEs are below the limit of detection (LOD) –63.3μg/L in the water samples of Yangtze River. Tongji River water are severely contaminated by PAEs, with the concentrations of di-n-butyl phthalate (DnBP) up to 613ug/L. Four of PAEs were detected in the tap water of Zhenjiang. It was also found that all of detected PAEs are dominantly partitioned on suspended solids in water samples. The concentrations of PAEs in sediment samples are ranged from

The forest carbon sinks play an important role in controlling the Greenhouse Gas emissions. The project management of wood carbon sequestration materials will be helpful to attract more and more enterprises to step into forestation, reforestation and technology development for improvement of forest management. That will create a sustainable situation that governments, NGO and corporations join together. Based on the domestic and foreign literature, the paper sorts out the current literature in the direction of forest carbon sequestration managements are from five aspects such as, carbon policy, carbon sequestration, carbon conservation, carbon substitution, carbon benefits. Based on this, the paper puts forward the policy and the long-term objectives of wood carbon sequestration materials should be integration of the implementation.

Global warming caused by CO2 and other greenhouse gas emissions has a direct impact of human existence, The current three sets of technological solutions corresponding to the global warming to develop low carbon economy such as improving energy efficiency and conservation, reducing the carbon content of energy, development and utilization of natural carbon sinks, are not only existence of selection bottleneck but also run hardly and cannot solve global warming in this century fundamentally. Wood carbon sequestration is a new global carbon pool based on technological innovation, combined with modern agriculture, created by means of industrialization. Wood carbon sequestration is not only a long-term carbon sequestration benefits storage body also can be a low-cost production resources or materials. To cultivate it to become an industry will not only become the new economic growth point for farmers to increase incomes, promote regional economic restructuring and industrial upgrading but also end the dependence of forest wood resources to human. This paper puts forward some corresponding countermeasures and suggestions on making reform on institutional level and the innovation of financial products to support the development of wood carbon sequestration materials industry, based on the financing obstacles to the development of wood carbon sequestration materials industry, form the significance of wood carbon sequestration materials development.

Three traditional color separation methods such as automatic color separation of fabric CAD, self-defined primary color separation and spot color separation are analyzed by comparison , the advantages and disadvantages of color separation based on cluster analysis are discussed by tests . On this basis, an improved fabric color separation method is put forward based on genetic fuzzy clustering algorithm, and the experimental results show that the fidelity of fabric patterns after color separation using this improved method is superior to that after color separation using traditional color separation method.

With the development of modem broadband radar, amount of reaserchers focus on broadband radar echo signal acquisitions and feature extraction of the target. Due to the large bandwidth as high as several MHz, the time interleaved ADC system is playing an important in radar echo systems, but this structure will bring in channel dismatch errors. The paper gave an explicit analysis of such three channel mismatch errors, and established the formulas of spectrum when all three mismatch errors exist together. Then presented the measure errors algorithm combined three errors according to the formulas of spectrum and the effective calibration algorithm．The algorithm was implemented in FPGA at last.