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Phytoextraction of heavy metal polluted environment generates large quantities of hyperaccumulators. How to dispose hyperaccumulators safely has been one of the most important issues in the phytoextraction field. In this paper, incineration technology was studied in order to investigate the feasibility of incineration technology on disposal of the arsenic-containing hyperaccumulator Pteris vittata L.. The tube furnace experiment examined the changes of arsenic in Pteris vittata L., studied the effects of factors including temperature, time, percentage of CaO on the incineration state. The results show that the most appropriate incineration condition was temperature of 400°C, time of 30min, percentage of CaO of 10%, which solved the problem to reduce biomass of Pteris vittata L. and volatilization of arsenic. The result provide insight into developing harmless disposal or resource-reuse-oriented methods for disposal of the plants used for large scale phytoremediation application.

PeneloPET is a PET-dedicated Monte Carlo simulation toolkit, which is based on PENELOPE. This article describes the characteristics and the general process of PeneloPET simulation. Then we compare the simulation results of PeneloPET and GATE to model the GE Healthcare eXplore Vista microPET system respectively, including sensitivity and noise equivalent count rate. The results show that PeneloPET simulation data corresponds with the data from real scanners and GATE simulation, and proves PeneloPET is an accurate toolkit for PET simulation.

The production and consumption of products and services exert much pressure on hydrological cycle. Water footprint is a popular indicator quantifying both direct and indirect water use of a product or service. In this article, water footprints were calculated for three milk products, 180g Yogurt, 250mL Fluid milk and 400g Skim milk powder (SMP) at product brand (YiYi®) level. The process LCA-based water footprint method was applied using primary production data, with both volumetric and stress-weighted results reported. Water footprint values were compared among different life cycle stages and products, and possible mitigation strategies to minimize the burden on freshwater systems from consumptive water use were raised. The results demonstrated the suitability of water footprint as streamlined indicator for product sustainability management and affirmed the importance of farming stage for water footprint reduction.

The hot preflex cooling and compound straightening are the last two consecutive deformation processes and determine the straightness, residual stress and cross-sectional size for fabricating hundred-meter heavy rail products. The compound straightening process needs to be adjusted by the preflex cooling status. For studying the straightness, residual stress and cross-sectional size of heavy rail products, the preflex cooling model (including the residual stress) of heavy rail after cooling should be taken as straightening model for studying the compound straightening. In this paper, the results by ANSYS implicit analysis (geometry model and stress state of the cold heavy rail) is fully imported to the compound straightening by ANSYS/LS-DYNA explicit analysis through an implicit-explicit conversion method, which resolved the connection problem of coupling and analysis models for solving complex models in multi-physical fields. It is very significant for solving the similar problems in engineering.

Creep property of coarse-grained soil is an important property influencing long-term settlement of embankment. Based on the H-K creep model which is consistent with the experimental results and verified by uniaxial compression creep test, relationship between fine grain composition and creep parameter and pattern of creep property of sandy slate coarse-grained soil influenced by fine grain composition are studied. It turns out that fine particle content is the important factor that affects creep property of sandy slate coarse-grained soil and using fine particle content of 30% is able to decrease long-term settlement of embankment.

Causes and main forms of collusion tender in the bidding of construction projects were analyzed. In accordance mainly with the characteristics of the collusion tender, one-off game and repeated game analysis models were established respectively on the two common forms of complementary bid and bid rotation between bidders. They were analyzed with the relevant principles of the game theory. Based on the results of analysis, strategy and measures to collusion tender were proposed from the perspective of the bid inviting party.

Uneven distribution of temperature is one of the important factors which influences heavy rail bending changes during the cooling process. Through the research of temperature field can reasonable analysis the heavy rail bending change rule, so it is necessary to study the temperature change rule during heavy rail cooling process. This paper adopts finite element analysis software ANSYS to set up three-dimensional models of U75V heavy rail and the cooling bed, and numerical simulate the cooling process. In which, it is studied the temperature changing rules and its distribution rules, emphatically analyzed temperature changing rule during the phase transition phase, and got the temperature changing rules and distribution rules in final cooling time. Especially, it is considered that the heavy rail placed on its side, the latent heat of phase transition and thermal radiation. This research can provide the theory basis and the advisory opinion on the formulation of cooling technological parameters and preflex regulations of the rail.

In order to meet mechanical mining demand of China's thin coal seaming, the power electronics and motor control system in hardware and software integration is presented, which replace traditional variable-frequency system applied to mining, planning and transport occasions. Solving braking resistor large volume and heat dissipation problem of the variable frequency system is very necessary. Accordingly, energy feedback based on fuzzy PI control type system to replace the traditional energy consumption braking was designed in this paper. Through the system simulation, it is shown that this system has high power factor, small feed current harmonics and effectively absorb the feedback energy, especially can realize four quadrant operations.

The operation characteristic of transformer when DC bias phenomenon occurred was detected by Epstein frame. Results with different methods of joint forms are obtained in this paper. The circuit structure and measuring principle were analyzed in detail. Average magnetizing curve, magnetic hysteresis loop and loss curve with joint forms method of full tap and 30°,60° tap were obtained. The theoretical basis and experimental evidence for improving the capacity on restraining DC bias during designing transformer are provided.

As the manufacturing technology of transformer getting more and more mature, issue of its vibration and noise is getting more and more attention. The vibration is more obviously when the transformer is running with DC Bias. 3D field-circuit coupling models of single-phase three-column power transformer was created by ANSYS. The simulating distributions of core magnetic flux density were obtained when the model was running with DC bias current of 0A, 0.9A and 2.6A. So were the modal shapes and curve of vibration-frequency of the transformer model. The theoretical guidance of reducing transformer vibration was obtained after analyzing the simulation result.

Transformer is irreplaceable to make sure power system running stably. It's showed in research that magnetic resistance is relevant to capacity on restraining DC bias both in three-phase three-column transformer and three-phase five-column transformer. Magnetic resistance can be changed by changing the seam size of transformer. 3D field-circuit coupling models of single-phase four-column power transformer with two kinds of seam were created by FEA in this paper. Models were simulated with different DC bias current. The analysis result of influence of seam size on power transformer's capacity on restraining DC bias was obtained by DC bias current efficient extraction and comparison of models with different seam size, which is the theoretical basis of developing new transformer with more capacity on restraining DC bias.

The cooling process of heavy rail is the important step to the output, that the preflexed rail is cooled on the stepping-type cold bed which has been carried by the chain transmission device. We employed the finite element method to analyze the bending deformation of the U75V rail through natural cooling process, the effected factors including the rail side-laying on the cold bed, the latent heat of phase change, and the thermal radiation are considered in the analysis. In the paper, we discussed the establishment of the heavy rail cooling model, the cooling parameters and the boundary condition, and emphatically analyzed the rail bending deformation changes and its principles through the cooling process. The study of the hundred-meter high speed heavy rail can provide the theoretical foundation and reference value to the formulation of cooling technical parameters and preflex technical schedule.

The people counting algorithms are widely applied in many areas. The algorithms may have lower counting accuracy or higher time complexity. To improve that, a new and high-accuracy people counting algorithm is proposed in this paper. It analyzes a background image and series population original images to calculate an average proportion for one person and create a two-dimensional table. Then it uses the average proportion and the two-dimensional table to count the number of people in test images. And two thresholds are adopted to regulate accuracy in counting.