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BEL-7402, HT-29, SPC-A1, U-251 bioassay-guided fractionation led to the isolation of the three active constituents from a wild fungi, Boletus edulis Bull. Ex Fr., which collected from Changbai Montain area. These three compounds’ chemical structures were elucidated on the base of spectroscopic data and comparison with known compounds as 5-cholestene-2,3-oxide (1), β-sitosterol (2), stigmasterol (3). All of the three compounds were extracted from Boletus edulis for the first time, and compound 1 was significantly cytotoxic against the four human cancer cell lines (BEL-7402, HT-29, SPC-A1 and U-251) with IC50 values 6.29, 6.98, 4.79 and 7.54 μM, respectively. Results of the study could supply referencs to the people to find the new drug from the fungus.

With the popularization of computer technology and application and popularization, the network technology has been widely used, the resulting network security issues are also increasingly prominent, to the network itself and the information system based on network constitutes the great potential safety hazard. This paper expounds the concept of intrusion detection and data mining, the commonly used invasion detection technology and models, and analyzes the application of data mining technology in intrusion detection system, to provide reference for the optimization and perfection of the network intrusion detection system and using for reference.

For achieving sufficient flame retardancy, high magnesim hydroxide (MH) content is needed in MH flame retardant Acrylonitrile-butadiene-styrene copolymer (ABS) composite (ABS/MH), which will cause difficulty in processing and poor mechanical property. We prepared modified flame retardant MH, fumed silica (SiO2) and zinc borate (ZB) via TX-10 phosphate/polyacrylate latex as well as MH flame retardant ABS with the modified flame retardant of 60.0wt% and studied the synergistic flame retardant effect of SiO2 and ZB with MH in ABS/MH. The incorporation of ZB, SiO2 or SiO2/ZB could prolong the time to ignition, reduce the average and peak heat release rate of ABS/MH in cone calorimeter test.

The acceleration and force sensors are taken as the measurement parameter,vibration power flow analysis is conducted to the data collected using MATLAB software,the results show that validity of engine suspension vibration is intuitively judged using the power flow,it is a evaluation index,moreover,it is not only convenient measurement,but also the influence of phase difference between the measured parameters to vibration isolation effect is not needed consider.

The damping effect of 485 diesel engine is taken as research object, on the same conditions, bench test is conducted respectively to self-developed MR fluid damper and traditional rubber damper, comparative analysis of domain and spectrum are conducted to collected test data using MATLAB, the results show that damping effect of MR fluid damper to engine is significantly superior to effect of traditional rubber damper.

The nonlinear and hysteresis characteristics showed by magneto-rheological (MR) mount make it seem very difficult to establish a precise mathematical model. Based on the testing of MR mount dynamics, RBF neural network model can train and forecast the collected data. Analysis of comparing the predicting result of the RBF neural network model with the testing result shows that the trained RBF neural network model can exactly predict the dynamics of MR mount, and it provides some new ideas to implement the better intelligent control of the engine MR mount.

Slope stability analysis is of great significance in geotechnical engineering, for which there are various research approaches as limit equilibrium analysis, numerical analysis, neural network based analysis, etc. Being one of the modern approaches, slope stability analysis based on GIS rises and develops swiftly. Authors give a brief introduction of the theory, research procedures, new developments and try to make it clear the new trend in slope stability analysis. Finally, the slope stability system which was developed based on GIS is introduced. The system which can analyze slope stability based on data mining including fuzzy clustering analysis, regression analysis, extension evaluation etc has provided with more powerful slope stability functions and is easy to be integrated

Focusing on the disadvantages of recent researches for roll planning that seldom consider the warm-up part and solution efficiency is low, in this paper, a parallel planning model and an improved ant colony algorithm were proposed to solve the problem. Firstly, the model considering constraints of both warm-up part and staple one was designed; Secondly, the improved ant colony algorithm was proposed where the slab cluster was used to decrease the searching scope and the local optimization to improve the efficiency of pheromone accumulation. Finally, with production data from hot strip mill, we proof the method can get the best results by comparing with other two ant colony algorithms.