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Spatial pattern of grassland community affects ecological processes, and the number of plant individuals is important to evaluate community dynamics as the fundamental ecological parameter of plant species, but so far few studies have dealt with spatial pattern of the number of plant individuals in grassland community. The research we present here explores whether the power law model can be used to evaluate spatial heterogeneity of the number of plant individuals of species in grassland community. As reference data, surveys of individuals were conducted on a natural grassland and a weed community, following random sampling method using 100 0.5 m × 0.5 m quadrats. We recorded the number of plant individuals of each species occurring in each quadrat. Our results show that (1) the power law model fits well to the spatial pattern of number of plant individuals, (2) the power law model can be applied to evaluate the spatial pattern of number of plant individuals in grassland community, and (3) spatial heterogeneity index value (δ) was positively associated with the average number of plant individuals ( m ) of species. Our research provides a new application of the power law model to study spatial heterogeneity of grassland community.

This paper studied the feasibility of applying ceramsite that is mainly composed of Pb–Zn tailings for cadmium removal in a laboratory environment. The influences of dosage, contact time, pH and the adsorption isotherm were examined via batch experiments. Further, two models including Freundlich and Langmuir isotherms were used to fit the experimental data. Results show that the removal rate of cadmium increases from 25% to 98% when pH increases from 2 to 12. Due to high efficiency, this type of ceramsite shows great potential for application in cost-effective elimination of cadmium from industrial wastewater.

Traditional mining tailings storage facilities may generate calamities and contaminants that cause the infiltration of tailings dam and even lead to dam failures. In view of this, new tailings storage facilities are designed in this paper by combining traditional tailings storage facilities with barrier systems including a vertical drainage system, a compound liner system, a fluid collection system and a caps system. With the vertical drainage system, water in contact with tailings can be transported into the fluid collection system. With the compound liner system, fluid can find a waterproof environment, which prevents the contamination of the environment such as surface water, groundwater, soil and food chain. With the fluid collection system, water in contact with tailings and fluid can be collected and removed to wastewater treatment plants, thus avoiding dam failure and AMD generation caused by the reaction of iron sulphides with water and oxygen.

One of the core responsibilities of many institutional traders is managing cash and risk constraints of a portfolio. Traders often do not take advantage of dark trading and block trading because of the risk of an unpredictable and unbalanced change to the composition of the executing list. Said differently, the randomness of dark fills makes it very difficult to constrain an optimization using dark as the only source of liquidity. In this article, the authors offer a solution to this problem using stochastic programming to create linear constraints for a quadratic optimization. They believe this research can be used by algorithm designers to bridge the gap between two dissimilar, yet useful, products: dark aggregation and portfolio trading algorithms.

Species richness (number of species) per small quadrat is an important characteristic of plant communities that, along with cover and biomass, can be readily measured in field surveys. We show that variance in the number of species among quadrats can be used to determine the spatial heterogeneity of plant communities. Comparisons between variance estimated based on the observed number of species among quadrats, and variance calculated based on an assumption that all species are arranged randomly among quadrats, can describe the spatial structure of species richness. We show field examples with different degrees of spatial heterogeneity in species richness to demonstrate how to survey, analyze and interpret: three natural grasslands with low heterogeneity in China, and a weedy grassland community with high heterogeneity in Japan.

The aim was to evaluate the protective effects of total flavones of Elaeagnus rhamnoides (L.) A. Nelson (TFE) against vascular endothelial injury in blood stasis model rats and explore the potential mechanisms preliminarily. The model of blood stasis rat model with vascular endothelial injury was induced by subcutaneous injection of adrenaline combined with ice-water bath. Whole blood viscosity (WBV), histological examination, and prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (FIB) were measured. Meanwhile, the levels of Thromboxane B2 (TXB2), 6-keto-PGF1α, von Willebrand factor (vWF), and thrombomodulin (TM) were detected. In addition, Quantitative Real-Time PCR (qPCR) was performed to identify PI3K, Erk2, Bcl-2, and caspase-3 gene expression. The results showed that TFE can relieve WBV, increase PT and APTT, and decrease FIB content obviously. Moreover, TFE might significantly downregulate the levels of TXB2, vWF, and TM in plasma and upregulate the level of 6-keto-PGF1α in plasma. Expressions of PI3K and Bcl-2 were increased and the expression of caspase-3 was decreased by TFE pretreatment in the rat model. Consequently, the study suggested that TFE may have the potential against vascular endothelial injury in blood stasis model rats induced by a high dose of adrenaline with ice-water bath.

Aluminium oxide (Al2O3) and titanium dioxide (TiO2) nanoparticles (NPs) have been widely used in nanotechnology-based products. Recently, researchers and the public have raised concerns about the adverse effects of these NPs in biological systems, particularly in humans. The aim of this study was to investigate the possible adverse effects of these two common metal oxide NPs on human lung epithelium cells (A549) and to investigate NP size-dependent effects on these cells, considering both the primary and hydrodynamic particle size. NPs were found to inhibit cell viability and proliferation at the highest concentration level (10 mg/mL) included in this study, as measured by a clonogenic assay. Moreover, cell viability, proliferation and metabolism were impaired to a greater extent by the smaller NPs (5 nm TiO2 and 10 nm Al2O3) relative to the larger particles (200 nm TiO2 and 50 nm Al2O3) included in this study, as measured by cell proliferation and metabolism. Notably, the observed cytotoxic effects corre...

This paper presents a genetic algorithm based model for soccer video summarization. The model first introduces audio features to improve fitness function which is used to calculate the relative differences among all the selected frames. Then the model employs crossover and mutation operators to get the meaningful summary in a video search space. Experimental results and comparisons are presented to show our model can get more reasonable and attractive frames than the traditional method on soccer video static summarization.

Impingers have been employed for collection of biological particles for a long time and the collection efficiency for submicron particles has been well studied for a few impinger models, like the SKC Biosampler and the AGI 30. These efficiency studies have been limited to particles larger than about 15 nm. The aim of this research is to determine the collection efficiency of ultrafine particles (from 3 to 100 nm) of a 25 ml midget impinger. The effect of different collection parameters (particle type, collection fluid volume and type and flow rate) was studied and results are presented here. All results showed minimum collection efficiencies from 3 to 10% at approximately 40–57 nm. Increasing the volume of the collection liquid and flow rate improved the collection efficiency of the impinger.

Nowadays, the driving technology of electric vehicle is developing rapidly. There are many kinds of methods in driving performance control technology. The paper studies the acceleration performance of electric vehicle. Under the premise of energy management, an acceleration power compensation method by fuzzy control theory based on driver intention recognition is proposed, which can meet the driver's subjective feelings better. It avoids the problem that the pedal opening and power output are single correspondence when the traditional vehicle accelerates. Through the simulation test, this method can significantly improve the performance of acceleration and output torque smoothly in non-emergency acceleration to ensure vehicle comfortable and stable.

this paper main around the polyphase structure of filter bank to design. First introduce the theory and the basic structure of multi-sampling. Utilize these can improve the original structure of the filter bank, obtained the corresponding polyphase filter structure. This structure has greatly improved the speed of the filtering computing. Then use FIR filters to realize filtering part, and introduced using FIR filters direct structure to achieve filter's hardware realization. And also introduced using FPGA to achieve a time selected by the base structure of 2-FFT algorithm, on this basis, to achieve the the computing of IFFT. Then according to the relationship between synthesis bank and analysis bank in overall structure of approximate reconstruction filter banks, synthesis filter banks can be designed to achieve approximate reconstruction of the signal. Finally, system commissioning test and experimental results verify the correctness and feasibility of the program.

This paper presents a Binary Genetic Algorithms (BGA) based video summarization system. The similarity functions are first defined to evaluate segmentation, which are extremely expensive to be optimized with traditional methods. Then the system employs binary crossover and mutation operators to get the meaningful summary in a video search space. In order to test performance of the BGA method, we first compare the BGA method with Decimal Genetic Algorithms (DGA) method. The obtained results show that it is more quickly to find the best results for BGA than DGA. Second, the BGA method and the uniform approach have been compared. Experimental results show that the BGA method can capture more information than the uniform method and reduce redundancy.

This paper presents a new genetic algorithm based method for video summarization. We pick out the least similar images from original video by measuring the differences with the technique of color histograms. Based on this reduced set, fitness function is defined for genetic algorithm to search the optimized frames. Experimental results show that the proposed method can capture more information than the traditional method and avoid redundancy. Moreover this algorithm has a distinct advantage in terms of time.

This paper presents the simulation results for a new dual-probe structure using multilayer PCB technology that is capable of performing power splitting across the whole of w-band frequency band from 75 GHz to 110 GHz. Existing single probe waveguide-to-microstrip transition design was employed for the new multilayered dual-probe structure, which proved to be effective in waveguide-to-microstip transition and power splitting. The new one piece multilayered dual-probe structure will provide ease in assembly, improve consistency and lower the manufacturing cost. Simulation results show that the return loss of the waveguide port to be greater than 10 dB and insertion loss better than 0.5 dB across whole w-band.

In order to improve the robustness and imperceptibleness of the image spread spectrum watermark algorithm, a new approach for optimization in 8times8 DCT domain using genetic algorithm (GA) was proposed. GA was used to choose the AC coefficients, which were modified to embed the spread spectrum watermark. The bands were varied to find the most suitable for image with different characteristics. Performance improvement with respect to existing algorithm is obtained by GA adaptive global search. The experimental results show that the proposed algorithm yields a watermark that is invisible to human eyes and robust to various image manipulation, and show that some special positions are the best choices for embedding the watermark. The authors also compare their experimental results with the results of the previous work of others

Traditional crossover and mutation have difficulties in searching the optimum individual because of the random selection of gene positions. In the paper, the impact of the crossover position and mutation position upon the diversity in the population is analyzed. Then the concept of efficient crossover position length is introduced and some important conclusions are given. Finally, a new kind of diversity-maintaining mutation is proposed, of which the mutation probability and position are varied depending on the gene diversity. In the rest of the paper a series of experiments are made to verify our ideas and sound results are achieved.