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Assessing current and potential future grassland vegetation types and distribution has important practical implications in grassland management. In this study, historical and projected climate data from Inner Mongolia were used to classify grassland classes for two historical (1960–1986 and 1986–2011) and two future periods (2021–2024 and 2041–2060) using the Comprehensive and Sequential Classification System (CSCS). Changes of grassland classes in these time periods were investigated. The results indicated that (1) using the CSCS provided an efficient approach to investigate the impact of historical and future climate on grassland classes and their distribution in Inner Mongolia over time and space; (2) since 1986, the precipitation in Inner Mongolia has declined, decreasing the semi-humid zone area and expanding that of arid and semi-arid areas. The area of Tundra and alpine steppe, Temperate zonal humid grassland and Temperate zonal forest steppe decreased, and that of Frigid desert, Semi-desert, and Steppe group increased; and (3) under the projected increase in temperature and decrease in precipitation in large areas in Inner Mongolia by 2060, the area of arid grassland classes will likely expand (Frigid desert, Semi-desert, and Steppe), and the grassland classes of Tundra and alpine steppe may gradually disappear. Government investment in infrastructure and grassland management measures such as introducing drought tolerant grass species and improved precipitation utilisation through irrigation are needed to adapt to the changing climate. Inner Mongolia should take advantage of the benefits of the increase in temperature in the eastern semi-humid region that would permit reduced grazing pressure in the western arid region.

The stochastic resonance (SR) theory provides a new method for the detection of weak signal submerged in strong noise. Aiming at the shortcomings of the existing technologies in low concentrations gas detection and the difficulties in optimising the system parameters of stochastic resonance, this paper proposed an adaptive parameters tuning algorithm and applied it in low concentrations gas detection. First, the input signal is preprocessed to satisfy the requirements of SR system, then we developed the adaptive parameters tuning algorithm to seek the maximum weighted signal-to-noise ratio (WSNR), which was used to evaluate the performance of the system. In the end, the relationship between the maximum WSNR and concentration of gas was analysed. The experiment results indicate that the proposed method is effective in low concentrations gas detection and could be expanded to other practical engineering applications.

The stochastic resonance (SR) theory provides a new idea for the detection of weak signal submerged in the strong noise. Combined with the optimization theory, this paper puts forward a stochastic resonance system based on genetic algorithm and applied it in a low concentrations gas detection. Firstly we preprocessed the input signal to satisfy the requirements of SR system, then developed the genetic algorithm to seek the maximum output signal-to-noise ratio (SNR), which was used to evaluate the performance of the system. In the end the relationship between the maximum SNR and concentration of gas was analyzed. The results of the experiments indicated the proposed method could improve the detection ability and enhance the detection limit of low gas concentrations.

This paper proposed a theoretically efficient approach for face recognition based on principal component analysis (PCA) and rotation invariant uniform local binary pattern texture features in order to weaken the effects of varying illumination conditions and facial expressions. Firstly, the rotation invariant uniform LBP operator was adopted to extract the local texture feature of the face images. Then PCA method was used to reduce the dimensionality of the extracted feature and get the eigenfaces. Finally, the nearest distance classification was used to distinguish each face. The method has been accessed on Yale and ATR-Jaffe face databases. Results demonstrate that the proposed method is superior to standard PCA and its recognition rate is higher than the traditional PCA. And the proposed algorithm has strong robustness against the illumination changes, pose, rotation and expressions.

The paper makes the simulation and analysis to the power harmonic which is produced by the AC drive device of the hot strip mill in the background of the metallurgical industry. Aiming at the line-side effects of AC-AC frequency conversion and AC-DC-AC frequency conversion control system harmonic, the paper makes the MATLAB simulation and analysis in three circumstances, such as the load parameters, the inductance value changes of transformer primary side and secondary side, and adding reactor etc., and defines the functions and value ranges of the line reactor. The simulation results can provide a design basis for the harmonic control and the power supply system when the system uses the variable frequency devices, and then improves the power supply quality of the large drag device.

As one of the new models of service of integrated manufacturing system, Cloud manufacturing (CM) is a service oriented, customer centric, demand driven manufacturing model.Application providers offer manufacturing services through the network, to make the cooperation among the participants of CM more effective. The behaviors of participants have great effect to the development of CM, especially in the beginning of its application.In this paper, we make analysis on interaction among all the participants of CM based on game theory, and give some suggestions to promote the application of CM.

In order to detect Volatile Organic Compounds (VOC) quickly and accurately, a portable electronic nose system was developed which including signal acquisition module, valve control module, embedded modules. Three sensors were used to measure methane, ethanol and formaldehyde gas. We used a three-way valve to control two kinds of gas, in order to avoid the system noise the zero reference was subtracted with the gas being tested. The system could quickly detect the three kinds VOC. The system can play a positive role in the rapid assessment of pollution in industrial parks.

Pain is one of the most important sensations in daily life, it is necessary to get the essence and mechanism of pain in pain treatment and control. In this article, the pain was induced through injection of angelica on the left shoulder of 12 volunteers, as placebo-control stimulation, the isotonic saline was injected. And through the spectrum analysis of EEG, the EEG feature, the power percentile of δ ,θ, α, β were extracted during the experiment to study the modulation effect of pain on brain information and central mechanism. The research demonstrated that the δ band energy ratio increased and the θ, α, β band energy ratio decreased after pain stimulation, though the activated areas were not strictly same, they mainly located on the left frontal cortex, left temporal cortex, left parietal cortex, occipital cortex. It indicated that these areas were modulated significantly by pain stimulation.

This paper presents a new strategy in wind speed prediction based on AR model and wavelet transform.The model uses the adjacent data for short-term wind speed forecasting and the data of the same moment in earlier days for long-term wind speed prediction at that moment,taking the similarity of wind speed at the same moment every day into account.Using the new model to analyze the wind speed of An-xi,China in April,2010,this paper concludes that the model is effective for that the correlation coefficient between the predicted value and the original data is larger than 0.8 when the prediction is less than 48 hours;while the prediction time is long ahead (48-120h),the error is acceptable (within 40%),which demonstrates that the new method is a novel and good idea for prediction on wind speed.

Cracking behaviors of oxide films on A3, 30CrMnSiA steel under applied stress were investigated in this paper. Theoretical deductions confirmed that critical cracking conditions for oxide films on A3 and 30CrMnSiA steel did exist. Electrochemical tensile experiments in 3%NaCl aqueous solution showed that the critical cracking stress for oxide film on A3 steel is about 220MPa,the critical cracking stress for oxide film on 30CrMnSiA steel is about 80MPa.In-situ dynamic tensile experiments verified the correctness of the experiments results in the electrochemical tensile experiments.

The slug flow regime may be appeared in subsea gas-liquid pipeline of the offshore petroleum industry. The gas entrainment process and the gas bubble distribution in liquid slug are crucial for the model of slug flow. An experimental facility was constructed and the gas bubble distributions in the liquid slug were measured by the dual-tip conductivity probe. It is found that the entrained gas is broken up into small bubbles by the high turbulent shear stress in the turbulent shear layer in the mixing zone. The small bubbles are dispersed completely and the profiles of void fraction and bubble frequency have peaks in this layer. The mechanism of gas entrainment is also presented.

The key to guarantee bending mold interchangeability is the precise detection of the cutting edge angle, symmetry and the distance from its center to the fitting surface of CNC bending mold. According to the features of the Key Dimension of the Bending Mold (KDBM), it is detected using a 3-DOF mechanical arm connected in series. The mechanical arm has a horizontal DOF, a vertical DOF, and a rotational freedom of the gauge head which is placed at the end of the mechanical arm. The Precision Detection Device (PDD) for KDBM that we have designed has high accuracy, good stability and rapid response.

According to the existing problems and shortcomings of the manufacturing enterprise quality management, integrating with enterprises’ new needs of quality management in the recent implementation of QHSE( Quality, Health, Safety, and Environment) system, this paper built an EII( Enterprise Information Integration)- Oriented QMS( Quality Management System) model, discussed the integrating problems involved in the system, then proposed the overall EII model. By analyzing the information integration relations between QMS and other enterprise applications, this paper put forward some practical ideas and principles of system integration, then built the framework of EII- Oriented QMS solutions. The aim of this paper is making full use of quality information, improving the quality of management and control, and helping manufacturing enterprises to better understand what EII- Oriented QMS is and how to make it a successful project.

A careful examination of the variation of the velocity along the centerline and the contour of a Laval nozzle in the physical plane shows that either the upper or the lower half of the Laval nozzle assumes the same form of a slitted thick airfoil with tandem trailing edges. These two airfoils lie on different Riemann sheets in the hodograph plane. The interior of the airfoil is then mapped onto an infinite strip in the complex potential plane. Making use of these results, we obtained an exact solution for the incompressible potential flow through a two-dimensional Laval nozzle. The solution is applicable for nozzles with any given contraction ratio mexpansion rations, and throat wall radius R*. As examples of the method, various nozzle contours, the velocity distribution of the flow, and the locations of the fluid particles at different time intervals are presented.

Reports on rapid economic growth as one fundamental change that has taken place in China since the founding of the People's Republic in 1949. China's gross domestic product in 1952; Readjustment and optimization of China's economic structure; Increase in the output value of the industries in China.

Reports that the National Bureau of Statistics of China has issued Provisional Regulations on Managing Survey Activities of Foreign-Funded Institutions. Reasons cited for the regulations; Main contents of the regulations; Impact of the regulations on the normal survey activities of overseas organizations; How overseas organizations will conduct social surveys in China.

Evidence from deep level transient spectroscopy (DLTS) and Fourier transform infrared spectroscopy (FTIR) measurements strongly supported the assertion that the degradation mechanism of ZnS:Mn AC thin-film electroluminescent (ACTFEL) devices is mainly due to the deep electron trap, Et, which comes from the Mn activators reacting with water molecules. The photoluminescence measurements revealed that the Mn-related Ettrap behaves like a nonradiative center. Furthermore, the X-ray diffraction experiments indicate that the crystallinity of ZnS:Mn phosphor films were destroyed in some degree by the Ettrap. As a result, poor brightness characteristics including lower brightness and higher threshold voltage were obtained when samples become aged.