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Grouping the similar processes is a good approach to improve the manufacturing efficiency, however, which is facing with two difficulties of the group automation and the constraints coupling. Regarding the numerical control (NC) machines and tasks as a grid system, this paper proposes a similarity-based tactic to solve the above difficulties. First, the methodology for analyzing the similarity among NC tasks is proposed to implement group automation taking the similarity principle as theory foundation. Second, based on the results drawn from the first step, the complex constraints including similarity constraints, delivery date constraints, and serial constraints are coupled to develop an integrated scheduling model. Finally, the integrated model is solved and the optimum solution is gotten using a specialized ants algorithm.

In this paper we develop a robust controller based on sliding mode, neural network and fuzzy logic for the control of a class of under-actuated systems. The stability of the proposed controller is proved with the Lyapunov function method. Simulation results are made on an inverted pendulum.

The present paper studied the enhanced effects of O3 and KMnO4 as chemical oxidants on traditional coagulation for micro-polluted raw water treatment. Results showed that pre-oxidation using either ozone or KMnO4 could effectively improve the removal of turbidity and organic matters by coagulation. Compared with mere coagulation by polyaluminium chloride (PAC), pre-oxidation using 2 mg/l O3 for 20 minutes could increase the removal rates of both turbidity and total organic carbon by 5.33% and 5.06%. However, the effectiveness of pre-oxidation using KMnO4 was not as significant as that using O3. Besides the direct mineralization of small organic molecules into CO2 and H2O, O3 and KMnO4 could also destroy complex macromolecules in raw water. Therefore, the SUVA value of the effluent decreased markedly after the pre-oxidation and the subsequent coagulation. Based on these results, the process of chemical pre-oxidation enhance coagulation were expected to reduce the disinfection by-products formation potential.

The wind speed simulation model was given in this paper, combined with the power system analysis software (PSD-BPA) transient calculation of wind generator models, it implemented the wind speed disturbance of wind farms and the entire network voltage analysis. Combining the practical power grid in china, research on the power grid voltage fluctuation of the level after the large-scale wind farms integrated the system, and relevant the conclusions: In the process of wind disturbance, there is no angle stability of synchronous generator in the system, doubly-fed induction generator could emit and absorb reactive power, and thus could be able to maintain voltage stability.

The hydraulic cylinder should be safety released in high-pressure situations, the release valve system is presented under such situation in this paper, which can release the high pressure from the hydraulic cylinder, in order to validate its feasibility, the simulation model of pressure release system is established in AMESim, the pressure release process of which is studied, the results show that the pressure relief system can release the high pressure of hydraulic cylinder smoothly, the pressure release system verifies the pressure control performance of control system, some of the parameters or factors of pressure release system are analyzed.

Anisotropic materials have been widely applied in practical engineering problems of interest. In the paper, the anisotropic heat transfer behaviors are analyzed using the proposed hybrid finite element model with Green’s function kernel. In the established weak integral hybrid functional, the element internal field being approximated with the combination of Green’s function satisfies a priori the governing partial differential equation and the independent frame field is assumed to link the internal field. As a result, the solving linear system of equations with boundary integrals only is obtained and the constructed elements show anisotropic feature. Two numerical examples are given to show the convergence and accuracy of the proposed approach, and the effect of ply angle of orthotropic material principal direction on the temperature distribution is discussed to investigate heat transfer mechanism in anisotropic materials.

Considering the features of slope rock mass failure, this paper applies residual thrust method and linear programming theory on the basis of finite element method, to assess safety of each cell of slope rock mass in dangerous zone. According to the slip field method to determine three-dimensional slope slip surface, to deduce three-dimensional stability analysis method based on symmetry breaking, a C++ based 3D-slope program is developed for purposes of three-dimensional slope stability analysis. Finally get the most dangerous landslide geometry and its safety factor, In the paper, combining with the engineering examples, the calculating results are comfortable to the practical failure.

Process simulation is a powerful tool to predict material behaviors under specified deformation conditions, so as to optimize the processing parameters. The equation for flow stress is important to numerically analyze. However, the reported constitutive equations of magnesium alloy are only suitable for processing simulation with strain rate between 0.001-1s-1. In this paper, the strain-stress behavior of AZ31 under warm and high strain rate (>103s-1) condition has been investigated by split Hopkinson pressure bar experiments at elevated temperature. The results show that the influence of the temperature on flow stress is more obvious than that of strain rate; the flow stress decreases with the rise of temperature at a certain strain rate. Based on Johnson-Cook model, the constitutive equation of AZ31 magnesium alloy under warm and high strain rate condition has been given out by fitting the experimental data, which can be applied in process simulation of AZ31 magnesium alloy sheet forming.

This paper describes the development of a software to perform three-dimensional crack propagation analyses. The software is based on the conventional finite element method with second order tetrahedral element and an automatic mesh generation software. Hexahedral finite elements have historically been used in fracture analyses and methodologies to compute the crack parameters have been developed for the hexahedral elements. In present research, the authors have developed a VCCM (virtual crack closure-integral method) for the second order tetrahedral finite element. Use of the tetrahedral element allows us to utilize an automatic mesh generation software. The direction and rate of crack propagation are predicted based on the stress intensity factors and the shape of crack is updated. Hence, a software package containing the modules for mesh generation, for finite element analysis, for stress intensity factor evaluation, for predicting the rate and the direction of crack propagation and for updating crack configuration, can be developed.

The temperature stability of scale factor (SF) has been analyzed and tested systematically for an optical voltage sensor (OVS) based on Pockels effect in this paper. The cardinal temperature sensitive parameters in sensor head and their impacts on SF are brought out by theoretical analysis and simulation method. Corresponding experiments are arranged to verify the validity of theoretical analysis. A real-time temperature compensation system is fabricated to reduce the error of SF in temperature fluctuation environment and its effectiveness is certified by experiment.

Buildings with masonry structures in rural areas of China have been the most severely damaged ones in earthquake disasters. This paper has analyzed the failure characteristics of rural masonry buildings in earthquake by summarizing the existing researches of the seismic resistance of masonry structures in rural areas, with its focus on the research of the intensity from VI to X. The constitutive relation model of damage developed by Yang Weizhong is used for the seismic analysis of rural masonry structures in combination with the failure criteria for masonry structures. The finite element software ANSYS is applied for the simulation and the results show that the damage of China's rural masonry structures regularly tends to weaken from the bottom to the top, with the seismic capacity of horizontal walls superior to longitudinal walls. As for vertical walls, due to their weak capacity, damage immediately occurs to them even in medium intensity earthquakes.

Yunnan province has rich natural resources with high species diversities because of its unique ecological environments, while the abundance of genera of seed plants endemic in Yunnan ranked the top one in China. But there are several shortcomings influence the research and the protection on genera of seed plants endemic in Yunnan. Firstly, the storage of relevant knowledge and data of genera of seed plants endemic in Yunnan is dispersion; secondly, the structure of the data system is poor; thirdly, the format and standard database is not unified. In order to improve the above shortcomings, this paper will built an ontology knowledge database for Yunnan genera of seed plants endemic based on ontology, geography ontology and ontology integration technologies. This new ontology knowledge database will apply new technologies and theoretical basis for the further macroscopic research on Yunnan genera of seed plants endemic. And it will apply scientific decision and research methods for optimization adjustment on distribution of genera of seed plants endemic in Yunnan.

The progression of application software and high-speed Internet access has, in general, the ability to commonly engage synesthetic experience. However, current synesthesia systems do not meet their full potential, as they are restricted by the simple display of non-intelligent two-dimensional form. This paper is going to present a system for enhancing visual and auditory attributes connection by augmenting the traditional sound visualization system with natural perceptual properties beyond two-dimensional space. A method of expanding the analysis capabilities of the system over changes in the frequencies and sound pressure levels of the live environmental sound stream was explored. With this method, a semantically rich four-dimensional form of sound containing information regarding audio properties and location could be generated. Some specific scenarios are discussed in order to explore visual form of natural perception of environmental sounds, multimedia voice and musical performance.

With the improvement of living standards, people living concept has changed, from the previous focus on practical, price and other factors, to put forward higher requirements on the natural ecological residential area landscape, environment greening. This paper first analyzes the residential district environmental landscape elements and design concepts, gives some principles of environmental landscape design in residential area, and finally puts forward the residential landscape design starting point.

This paper describes the building roof structure characteristics and aesthetic appreciation of the western Sichuan local-style dwelling houses. Through to introductions of the whole structure of the roof and roof tile, more and more people will know the characteristics of western Sichuan folk house.

This paper analyzes the dialectical relationship between the hazards and risks to find out the common things of ways and methods to control them and then analyze and discuss several classification of sources of danger to propose specific ways and methods to management of coal hazards. On this basis, we design and develop appropriate management system of coal hazards, in order to achieve effective management of risks.

This paper designed an analog control circuit which can automatically track the sun for PV bracket system to improve the solar cell photo-electricity conversion efficiency. The sunlight intensity can be real-time detected by sampling the short-circuit current of solar cell. The PV bracket system can be automatically adjusted to achieve a final horizontal angle and pitch angle by using the hysteresis comparator and dedicated motor driver chip, which always makes photovoltaic modules toward the sun's position. At the same time, the PV bracket system can be automatically reset by the hall switch when the sun reaches the sunset and the light intensity is less than the reference value. The experimental prototype is used to testify the correctness and reliability of the control system, which has better practicability and value to extend.

The development of ecological architectural theory in China and the revival of traditional feng-shui theory have become a huge driving force for the development of eco-building today. In this paper a comparative study of ancestral halls in east Hubei province is made from the perspective of building orientation, topography, building space and building materials and other elements related to both eco-building and feng-shui theory and a conclusion is reached that the essence of feng-shui theory is consistent to the ideology of contemporary ecological architectural theory, which the author hopes will provide some references and a scientific basis for the sustainable development of ecological buildings with Chinese characteristics in China.

Since thermocouple has an intrinsic disadvantage that its signal is very weak, many problems usually appear such as large noise and low temperature resolution when thermocouples are being used. Aiming this defect on thermocouple measurement, this paper proposes a solution of analog circuit design that provides the character of low noise and high SNR. This paper discusses the analog circuit design and calculation based on the S-type thermocouple which is often used for a very wide temperature range. This designed module can be applied to measurement instruments.

Corrosion of steel structures has been found to be a problem Corrosion can be managed but not eliminated, so detecting corrosion will remain an issue no matter how effective corrosion prevention programs become. Electrochemical reaction is the basically process of steel corrosion in civil engineering, so electrochemical method is the best way to monitor corrosion grade. Liquid state reference is often used in lab to study steel corrosion by triple electrode system, but it is very difficultly used in steel bar corrosion monitoring in civil engineering. Firstly, liquid reference’s life is, generally speaking, very short. The steel corrosion is a very slow process, corrosion monitoring should be tens of years, so the liquid reference’s life is not long enough for corrosion monitoring; Secondly, the reference electrode’s strength have to be very high. Obviously, liquid electrode reference can not meet the requirement. In this paper, a novel all solid state reference electrode (ASSRE) has been developed. There are three layers in the electrode. Four kinds of components have been included in first and second layer. Additional AgCl powder has been used to inhibit AgCl decrease which is on the surface of Ag wire by complexing effect. There is only one kind of component in third layer. There are four steps to prepare the reference electrode: electrolyze, pre-mixed components, modelling and sintering. Finally, the potential of ASSR has been measured by SCE.