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In order to improve the performance of end face grinding wheel, the phyllotaxis theory is introduced into the design of the wheel. Meanwhile the movement track equation of the end grinding is established, and the effects of the phyllotactic coefficient on the grinding surface roughness are studied. The simulation results show that the lower surface roughness values can be obtained when choosing reasonable phyllotactic coefficient. It will provide theoretical basis for the ordered abrasive patterns of the end grinding wheel.

A hybrid graph and rule-based method for recognizing machining features is proposed in this paper, which aims to get the machining feature in 3D in-process model construction system. Initially, the attributed adjacency graph (AAG) of the input MBD models is constructed and represented in matrix form. After that, by deleting the convex edges of the AAG, the concave sub-graphs are generated. For obtaining the volumetric features, their concave sub-graphs are matched with the feature template graphs in a pre-defined library; for those which can be generated by sweeping the edge loops, such as open pocket, closed pocket, through pocket and slot, their features are recognized by using rules. In experimental section, an example is given to illustrate the validity and effectiveness of the proposed method.

The cadmium removed from sediment by rhamnolipid biosurfactant was explored in laboratory scale. The results suggest that the biosurfactant can remove cadmium from the sediment efficiently, 40% more than SDS. 200 mg/L rhamnolipid biosurfactant can get 84.02% cadmium removal efficiency from the sediment which contained 0.42 mg/g cadmium. pH affect cadmium removal by rhamnolipid, the best pH was 10. Leaching could also affect cadmium removal, there was a remarkable increasing of cadmium removal efficiency after the second washing, and after 48 h leaching cadmium removal and cadmium absorption got the balance.

In this work, in order to improve the operation speed of groundwater flow numerical model, we studied the approach of solving linear equations and the relative acceleration problems based on CUDA platform. We developed the GPCG module base on GPU platform to replace PCG module of MODFLOW 2005 by using NVIDIA TESLA C2070. We obtained the effective acceleration results on GPU platform, by establishing series of ideal and instance models, which showed that the overall speedup of the models is around 2.5times and the calculation speedup is about 10times.

Artificial organic polymer flocculants has been widely applied in water treatment; however, disadvantages of nonbiodegradable and poisonous may cause another environmental problem. This paper established an effective water treatment technique using Abelmoschusmoschatu (Okra) in combining of glue extraction process and flocculating process, with fully consideration of factors such as treating time, cost, and efficiency. Results showed that ethanol extraction was an effective method for extraction of glue form Okra. After being soaked in distilled water overnight with ratios of material to solvent, and was extracted by ethanol with volume percentage of 50% at stable temperature of 70 °C for one hour, the extraction rate of Okra glue could be as high as 18.38%. The glue usage of 0.015-0.020 g.L-1 and flocculating time of five minutes could be the optimal usage in treating suspending liquid of kaolin, with the turbidity of 3.0 g.L-1. The processes are low cost, simple, efficient, and low pollution, having broad application prospects.

To reduce the workload for marking the dimensions of in-process models, a method of dimension marking based on manufacturing features for in-process model is proposed. Firstly, the dimension information is extracted from model based definition (MBD) models; secondly, the feature dimension chains are constructed according to the feature location dimension and the process data, when the process data and design data are not coincided with each other; thirdly, the process dimension tolerances are calculated by using the increasing links and the decreasing links of the MBD. In experimental section, an example was given to illustrate the validity and effectiveness of the proposed method.

Space induced rice mutant research focus on the various effects which caused by space environment on rice gene. To express, describe and manage the large number of data with diverse data formats, that are generated by field experiments and a series of genomic and proteomic molecular biology experiments, database technology is used for database modeling in this paper. The implemented system with applied technology is able to organize, manage and analyze data effectively. The analysis results are used to obtain the meaningful data, guide further experiments and lay the foundation for subsequent data analysis and data mining.

The characters, research and utilization of Ground Granulated Blast Slag are presented in this paper. Some current use of GGBS in soft soil treatment is introduced. In addition, the paper also focuses on the comparative analysis of the effects of GGBS and Lime Stabilization which is the traditional method in soft soil treatment on compaction characteristics & Atterberg limits. Next, the strength mechanism of GGBS, a kind of Soli Stabilizer applied in soft soil treatment, is mainly explained and also the validity of GGBS has been proved. All of these indicate that GGBS has the superiority of social benefit, economic benefit and environmental benefit in soft soil treatment.

Modal analysis and vibration analysis is the foundation of dynamic characteristics analysis and it is the most important methods to analyze the inherent characteristics and mode shapes of the system. In this paper, the airport tractor frame is taken as the research object and its geometric model is established by Pro / E, 10 order modal and shapes of tractor frame is obtained by ANSYS. The results showed that: the first and second frequency of the frame is avoided the engine idling, the outbreak frequency, and excitation frequency in normal driving road. The entire frame meets the requirement of the dynamic characteristics.

Suspension spring is used in the suspension system of light vehicle and medium buses widely, and its design quality related to stability and security of the vehicle. This paper take the suspension coil spring of a light vehicle as the research object, its multi-objective optimization model is established. The volume of spring and one frequency free vibration frequency are taken as optimization objective, the strength, stiffness, stability, fatigue strength and the winding ratio of the spring are taken as constraints, and use NSGA-II algorithm, obtained Pareto optimal solution set of the optimization problem. The coil spring model and optimization method used in this paper is also suitable for optimization design of other spring.

Using Airpak as CFD tool, the study simulates and analyses how the openings and thermal characteristics of the clad façade work on the distribution of temperature and ventilation in the atrium of a high-rise building in Shenzhen. The result shows that, with the atrium roof open to the air, openings on the lower part of the clad façade can significantly improve air ventilation and reduce the temperature in the atrium in summer. It is also found that clad glazing of large U-value and large SHGC helps to release the residual heat in the atrium, which make laminated glass made of clear float glass smart choice for the clad glazing of the building.

The exhaust noise, which falls into low-frequency noise, is the dominant noise source of a diesel engines and tractors. The traditional exhaust silencers, which are normally constructed by combination of expansion chamber, and perforated pipe or perforated board, are with high exhaust resistance, but poor noise reduction especially for the low-frequency band noise. For this reason, a new theory of exhaust muffler of diesel engine based on counter-phase counteracts has been proposed. The mathematical model and the corresponding experimental validation for the new exhaust muffler based on this theory were performed.