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The sliding mode control approach based on double power exponential reaching law is proposed for the hydraulic servo system. With the example of the hydraulic servo system in the lab, the mathematic model is established and the new controller is presented and simulated. Simulation results show that: the proposed approach has high track precision, fast response, small chattering and ensures dynamic quality of the system.

In recent years, with the development of modern technologies and safety science, catastrophic accidents tend to be avoided successfully. However, general accidents which cause minor loss or casualties still occur occasionally and hence become main part of all accidents. Therefore, to make effective control of general accidents, fault trees are established based on the analysis of historical general accidents. The influencing factors are roughly divided into human factors and equipment system factors. This paper focuses on human factors and the relationships between the factors and general accidents are analyzed using the improved analytic hierarchy process (AHP) and methods of risk identification. The importance of the factors is thus evaluated. Results of the evaluation are helpful to management.

The purpose of this study was to analyze the existing problems and put forward the corresponding settlement measures with the basic data of road transport facilities, water supply and drainage facilities, energy and power facilities, environmental facilities and communications facilities of 31 provincial capital cities and municipalities directly under the central government of China. AHP was used to get the comprehensive value and orders of overall level of infrastructures’ safety in major big cities. Results of the 31 city infrastructure overall safety level of sorting were summarized, and the existing problems and the reasons were got. Conclusion was drawn that the overall safety level of infrastructure in China needed to be improved and the infrastructure security level of east central area was higher than the western region with a poor gap. The economic development level, the degree of government’s attention, population density together with natural conditions were all important factors which influence the urban infrastructure security level.

Composite materials (also called composition materials or shortened to composites) are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. The new material may be preferred for many reasons: common examples include materials which are stronger, lighter or less expensive when compared to traditional materials. Composite materials are generally used for buildings, bridges and structures. The most advanced examples perform routinely on spacecraft in demanding environments.

Enterprises of freight transport on a special route have to own alliance cooperation system with high efficiency in order to build alliance of freight transport. Selecting cooperative partners is the basis for establishing an efficient transportation system. The paper firstly analyzes the principle of selecting cooperative partners of freight transport alliance on a special route, summarizes the indicator system of selecting cooperative partners of freight transport alliance on a special route, establishes analytic hierarchy process model and finally proves the model with examples.

To solve the problem that traditional automatic image clipping method is on the basic of simple principles, such as fixed size and fixed location, an improved arithmetic based on face recognition is proposed. Firstly, the face region is located by face detecting.Then according to the proportion of face area in the selected region on the template image,the clipping region size of the image to cut is matched.At last,through the relative position of the face center in the template image,the cutting position can be got. The experimental results show that this algorithm can achieve better clipping effect.

Text classification presents difficult challenges due to the high dimensionality and sparsity of text data, and to the complex semantics of the natural language. Typically, in text classification the documents are represented in the vector space using the Bag of words (BoW) technique. Despite its ease of use, BoW representation does not consider the semantic similarity between words. In this paper, we overcome the shortage of the BoW approach by applying the exponential kernel, which models semantic similarity by means of a diffusion process on a graph defined by lexicon and co-occurrence information, to enrich the BoW representation. Combined with the support vector machine (SVM), experimental evaluation on real data sets demonstrates that our approach successfully achieves improved classification accuracy with respect to the BoW approach.

Accurately estimating the deformation of high-rise building is a very important work for surveyors, however it is very difficult to get an accurate and reliable predictor. In this paper, artificial neural network has been applied here because of its good ability of nonlinear fitting. On the basis of the high-rise building monitoring data, three prediction models including the BP, RBF and GRNN neural network prediction models were established, the comparative analysis for the prediction accuracy of the three models was obtained. The results show that neural network is capable for prediction, and GRNN possess higher capability in prediction and better adaptability in comparing with other two neural networks.

A basic engineering cost management system is basis about the engineering cost management for national or regional. As the main basis of engineering cost is determined by two factors are engineering quantity and unit price, so the basic engineering cost management system should reflect the management and control model in the project of "quantity" and "price" of these two aspects in any country or region.

The change law of gel time of calcium carbonate-acid water glass grouting material with the content of calcium carbonate is researched in this paper. But the gel time does not increase evenly with reduction calcium carbonic reducing. It increases suddenly because there is sudden exceeding range with the solution pH value increasing. Meanwhile, the change relation of strength of pure gelation with suitable gel time and time is measured. Firming sand strength experiment is conducted by the better mixture ratio. The strength of pure gelation body increases with the time and the content of calcium carbonate increasing. It is closely related with the reaction mechanism of calcium carbonate-acid water glass. The active Ca2+in this system can react with a series of silicate ion to form silicate precipitate which is filled with colloid and forming skeletonation. And the correlation between firming sand strength and the calcium carbonic acid content is non-significant. Finally, the contrast test of the water glass-glyoxal is done, which is the preparation for the subsequent engineering application.

Based on the PLC control technique and WinCC configuration technology,the control system for the liquid level of the tank was designed. After receiving liquid level signal that transferred from radar tester,the PLC process it ,and then output related control signal to the actuator.The actuator is composed of two AC motors,one is for the main pump ,and another for the auxiliary pump.The function of human-machine interface is achieved with the help of Smart700 touch screen of Siemens.Communication functions between the WinCC project and the PLC site and pictures of the control process which enabals real-time monitoring of the entire system are finished by designing configuration.Finally,the validity of the system and the feasibility of the design have been proved by debugging and the use of enterprises.

This paper proposes the classification algorithm of news pages based on domain Ontology. In order to improve the shortage of current classification algorithm that only considers the content similarity, this paper presents the semantic classification method which considers both content similarity and structural correlation. Firstly, it parses the Ontology to get Ontology category vector, extracts keywords of news pages texts and drops semantic dimension. At this time, finding out the same vocabulary and ontology category vector in page texts to constitute the text expectation vector, and then calculating the content similarity between ontology category vector and expectation vector of text by using the law of cosines. Secondly, the common vocabularies are mapped to the ontology hierarchy chart, and the structural relevancy is obtained by calculating weighted path of this directed acyclic graph. Finally, it calculates the correlation degree of the news pages and Ontology by combining both, and determines the category of news pages by judging the size relationship between the result and the initial threshold value.

After background modeling and segmenting of moving object for surveillance video, this paper firstly presented a noninteractive matting algorithm of video moving object based on GrabCut. These matted moving objects then were placed in a background image on the condition of nonoverlapping arrangement, so a frame could be obtained with several moving objects placed in a background image. Finally, a series of these frame images could be achieved in timeline and a single camera surveillance video synopsis could be formed. The experimental results show that this video synopsis has the features of conciseness and readable concentrated form and the efficiency of browsing and retrieval can be improved.

This paper introduces a traditional method of concept extraction. Considered some defects which this method will miss some concepts having synonyms and the relationship of “is-a”. It gives the improved algorithm to extract them. The result of the experiment shows the feasibility of this method.

The offshore wind turbine (OWT) tower is the important support of the whole wind turbine components, it is necessary to design and research the tower reasonably in order to ensure reliable operation of the OWT. In this paper, 3MW OWT tower is chosen as the object of study. A gas-liquid-solid model of the OWT tower and its external environment is built using COMSOL Multiphysics software. Combined with the two-phase flow theory of gas-liquid, loads of the tower under the coupling action of wind and wave are computed, which provides a new direction for the load analysis of the tower. The results calculated by this method are closer to the physical truth, which provides a more reliable basis for analyzing the fatigue life of the tower further.

In this information society, the traditional method of ontology construction can’t meet the demand for researchers. Because it’s a difficult task to build ontology by hands. The research of automatical construction of ontology is still in the primary stage, especially in the law field. Considering the above condition, this paper gives a Research on Ontology Construction Automatically in the Law Field; we put forward the method of using LLR formula in the step of term abstraction to improve the precision and applying K-means clustering algorithm to obtain better relations of concepts hierarchy. Compared with the approach of constructing ontology by hands, it gets better effect on the law ontology.

Based on the proposed efficient cyclic correlation estimator by exploiting normalized infinite norm, this paper develops a robust adaptive time delay estimation method which provides additional robustness against heavy-tailed noise and when the noise statistics are not fully known. Simulations demonstrate the reliable and robust performance of the proposed cyclic correlation estimator and its corresponding time delay estimation algorithm.

Jianli Reach has long been exposed to labile main flow and the frequent translocation between the main channel and the lateral branch. To investigate how the long-term process of flow-sediment influences the adjustment of river channel pattern, monthly time series (1951-2009) of runoff and sediment load at Jianli hydrological station of Yangtze River were analyzed using three methods: R/S analysis to estimate Hurst exponent, Mann-Kendall method and the time series anomaly analysis. The result shows that on 1 year time scale, the values of Hurst exponent are indicating persistence, that is to say, the trend of runoff and sediment in the future will generally be the same as the past, and the persistence in runoff series is stronger than that in the sediment load. The period of oscillation in annual runoff and in sediment load is about 30 years. The result of Mann-Kendall test shows an abrupt change point of runoff time-series at 1967 and an abrupt change point of sediment load time-series at 2003. And during the flood season, the values of Hurst exponent still indicate persistence, which is weaker than that in whole year correspondingly.

In real estate industry, there exist some contradictions, including less land supply and higher residential demand, high residential vacancy rate and growing residential demand, resource waste owing to short-term investment and limited resources, high prices and low purchasing power. The paradox matter-element extension theory is fit for the contradictive study, and consistent with the sustainable development of the real estate industry in terms of research subject, logic theory, and variability. On basis of these, this Study establishes extension-theory-based evaluation index system for sustainable development of real estate industry, in which the indices are categorized into five groups: economy and finance, social equality, ecological environment, resources utilization, and government management.

With the rapid development of wind power industry and the increasing tension of land resources, WTGS(Wind turbine generating set) changes from Onshore wind machine to offshore wind machine. Because the offshore wind turbine works in the complex environment, it is a higher challenge for tower security. This paper focuses on the load analysis of 2.5MW wind turbine tower, in which a segment solution is applied. Wind load is solved in the superior segment of tower. In the lower segment, the coupling factor of wind and wave is taken into account. Irregular waves are simulated on the basis of the linear wave theory, and then wave load is derived. Accordingly, loads on the tower are calculated by using MATLAB software, and the load spectrum of every node is drawn, which lays a foundation for the dynamic response analysis and fatigue life analysis of tower.

This paper presents the development of a dynamic model of the valve train of one engine. During the parameter determination of the model, finite element method is used to calculate the contact stiffness of the cam-follower . The simulation results of the model are compared with measured data of the valve train at same speed. Excellent quantitative agreement is found between the numerical and experimental results and the validity of the dynamic model can be verified.

Accurately estimating the deformation of tunnel surrounding rock is a very important work for surveyors, and we adopted grey model as a forecasting means because of its fast calculation with as few as four data inputs needed, however, the original GM (1, 1) model is not fit for dynamic and long data prediction. For this purpose, we propose a novel approach to improve prediction accuracy of GM(1,1) model through optimization of the initial condition and adoption the technique of rolling modeling, the new forecasting model termed RnGM(1,1). By using the optimized model to analyze and predict the deformation of tunnel surrounding rock and comparing this optimized model with other models, we finally draw a conclusion that this optimized model is able to improve the precision of prediction and therefore can be applied to deformation data analysis.

Polystyrene microspheres were prepared by the emulsifier-free polymerization method. Using the polystyrene microspheres as seeds, p-nitroaniline as template molecules, the monodispersed molecularly imprinted polymer microspheres (MIPMs) were prepared by a single-step swelling and polymerization method. The monodispersed molecular imprinted polymers with porous structure were characterized by SEM, and UV-visible spectrophotometry. The adsorption performance of MIPMs for p-nitroaniline was investigated.

Opportunistic networks is one of the newest hot research spots in wireless networks after mobile ad hoc net-works(MANET) and wireless sensor networks(WSN). Mobility model describes mobility manners of nodes. It has been widely used in research on wireless network. This paper firstly introduced, classifies, and compares the current familiar mobility models. Secondly, it classifies, and compares the current familiar mobility models. Next, it was discussed that current research focus on new mobility models, analysis of nodes mobility features, trace strategy, and evaluation of mobility model. Finally, this paper involved what calls for further study.

Local Universities are an important part of higher education in China. The discipline as the core element of higher education is the basic strategy unit which supports teaching, research and social services. The development level of the discipline represents higher education development. From the perspective of technological innovation in the development of disciplines, this paper studies the discipline evolution, which based on ant colony optimization theory. We constructed a mathematical model applied to the discipline evolution.