Abstract: At present, the environmental risk has become science foundation and one of important basis of the environmental risk management and environmental decision-making. This paper based on the chemical properties of carbon disulfide including physical and chemical properties, toxicity, explosive harms characteristics are studied and puts forward some preventive measures.
Abstract: Nanotechnology has become a comprehensive high-tech subject, and will be the core in the next technological revolution times. With the flourishing development of nanotechnology, it is clear that its research and development have become the hot spot these days for the international scientific community and the engineering community. In this paper, content and development of nanotechnology are discussed in details, as well as the analysis of its application in the field of micro-mechanical, non-friction micro-nano-bearings, the new metal-ceramic nano-tools, nano-magnetic fluid sealed in the ultra-fine grinding machine, etc. And looks forward to applying the nanotechnology in our country.
Abstract: The microwave vehicle detection can obtain real-time conditions of road traffic flow fast, accurate and convenient. In this study, we took the expressway traffic flow in Chengdu as the research object, collecting real-time data of traffic flow, speed and vehicle density to analyses the relationship among Q, V, K graphically. Finally the service level in different lanes and speed in the Third Ring Road were evaluated through Q, V, K data calculations and analysis in Chengdu’s expressway at the traffic peak time.
Abstract: This text applies grey target theory to evaluate the safety of highway alignment design. According to grey target theory, many factors which affect the safety were selected. The model of the safety evaluation of highway alignment design model was put forward based on grey target theory. After we apply this method in the practice, this method of the safety evaluation of highway alignment design is proved to be effective in course of the accuracy of the safety evaluation. Investigative results indicate that some subjective factors can be eliminated to a certain extent based on evaluation model of grey target theory in the course of alignment scheme choice，which make the choice result more objective. And it is a certain application value for the safety evaluation of highway alignment design.
Abstract: A superhydrophobic complex coating for cotton fabrics based on silica nanoparticles and new fluoroalkylsiloxane polymer was reported here. The complex thin film was prepared through sol-gel method using cotton fabrics as a substrate. Silica nanoparticles in the coating made the textile surface much rougher, and new fluoroalkylsiloxane polymer with reactive groups on the top layer of the surface lowered the surface free energy and enhanced the binding between silica nanoparticles and the fluoro-containing polymer. Textiles coated with this coating showed excellent water repellent property, and water contact angle (CA) increased from 138° on the pure fluoroalkylsiloxane polymer treated cotton fabric up to 156.5° on complex one. Moreover, this superhydrophobic complex coating possesses favorable washing durability and its CA still retain 106° after 20 times of soaping operations.
Abstract: Five kinds of vinegars were measured by a gas sensor array composed of six TGS gas sensors. The sensor array should be optimized by the minimal Wilks statistic value, then, the four best sensor array used to detect the type of vinegars were formed, Principal Component Analysis (PCA) and Linear discriminant analysis (LDA) were applied to analyze the data of primary and optimized sensor array. The results indicated that optimization sensor array could be more adaptable to recognize the five kinds of vinegars. Thereby the given optimization method is effective.
Abstract: The operation speed of modern embed system has been upgraded from several hundred MHz to GHz. The signal vias through power/ground plane can have strong coupling effect and result in signal integrity problem. Analytical model including calculation of resonant frequencies, fields for simple rectangular structures can be used to estimate the resonant frequency and ideal position to place signal vias. Based on FDTD algorithm, a numerical modeling of powerd/ground plane with lumped elements is presented. The coupling effect between signal vias in power/ground plane with lumped elments can be analyzed by this model. Finally, coupling effect between signal vias under different conditions are discussed and some methods to improve signal integrity are proposed.
Abstract: The cascade-correlation(CC) is presented as a neural network growing technique which allows one to gradually build network architecture without the need to redefine the number of neurons to be used in a feed forward. In view of the actual situation that the corresponding space curved surface which expresses pressure fluctuation in draft tube is too complex to be analyzed, considering the pressure fluctuation in draft tube, the network model is established based on CC algorithm and it is applied to hydropower station. Comparing with BP neural network, the experimental results show the prediction precision of the final model is higher and the prediction values are in better agreement with the real values.
Abstract: Relevance Vector Machine (RVM) is a novel kernel method based on sparse Bayesian, which has many advantages such as its kernel functions without the restriction of Mercer’s conditions, and the relevance vectors are automatically determined and have fewer parameters. In this paper, the RVM model is applied to forecasting groundwater level. The experimental results show the final RVM model achieved is sparser, the prediction precision is higher and the prediction values are in better agreement with the real values. It can be concluded that this technique can be seen as a very promising option to solve nonlinear problems such as forecasting groundwater level.