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This article introduces, by the application of equivalent conversion of line integral of probability integral method theoretical model, the research of the system architecture, main function and key technology of the intelligent mining subsidence prediction system which includes mining subsidence prediction and surface movement station parameters obtainment and can directly connect with the AutoCAD which is generally applied in mining area. Combined with specific engineering, this article introduces the actual application condition of this system to guide the safety production of coal mine and to assist engineering designers to work on the mining subsidence prediction better.

Considering the changes of MP2P topology due to the limitation of the capability, the unreliable and the churn of the node, the paper proposes a efficiency and safety resource node selection strategy based on Altruism and Bayesian Game in MP2P network. Firstly, obtaining the resource node altruism degree from the value of the contribution and profit of the node . Secondly, adopting the static Bayesian Game theory to connect the resource nodes, the strategy can increase the downloading resources quantity and enhance the ratio of successful request.

PLLA / OMMT composite films were prepared through solution casting method, in which chloroform was used as solvent. Mechanical, thermal and crystallization properties of neat PLLA and PLLA / OMMT composites films were investigated as well as morphology through scanning electron microscope. It was shown that tensile strength of PLLA / OMMT composite films gradually increased with increasing OMMT content, but reduced when more filler were added. Loading of 2wt% of OMMT seemed to benifit PLLA in tensile strength most. With the increase of montmorillonite content, the elongation at break of PLLA decreased first and then reached to a steady level. When compared with pure PLLA, the composite system showed decreased spherulite size, lower degree of order and an increase in the number of grains. Thermal analysis has proved that the addition of OMMT greatly enhanced crystability and thermal stability of PLLA.

Coal mining and filling connection is very fast in continuous mining and filling working face. How to build airtight walls at ends of filling stope drift efficiently is one of the bottleneck problems, which restricts production improving in continuous mining working face. This paper presented a design idea of the rapid prototyping mold bag wall, analyzed its structure, did much research and finally provided the design. Field application showed that it improved construction efficiency and reduced cost.

Compared with the conventional piston engines, the new rotary engine has many significant advantages, such as smaller volume and higher power density. Current studies at home and abroad are mainly focusing on aspects of its structural design, kinematics, dynamics analysis, except mechanical efficiency. In conventional piston engines, frictional loss of the piston group accounted for 65% of the total friction power loss[1]. In order to provide the scientific basis for designing low friction piston of the rotary engine, this paper combine the average two-dimensional Reynolds equation, the asperity contacts equation, viscosity-temperature equation and loads balance equation, proposing a method for calculating the friction power loss, and the applying the method to calculate the friction power loss of piston group of a new rotary engine.

This paper modeling the piston ring of a new double-rotor engine based on the analysis, use Matlab program some code and woke out the numerical solution of the model,analyze the change of the gas leakage in the condition of different gas-room volume, different opening area, different spindle rotational speed, which provide strong evidence for improving sealing of the new double-rotor engine and ameliorating sealing design.

Using sysweld software based on the Gauss heat source, simulated welding process of 45 steel plate, analysed welding temperature field、stress and strain. The maximum stress value appeared at the initial welding position of junction of base metal and weld. As the most dangerous section, the maximum strain value appeared at the end welding position of the junction of base metal and weld. Compressive strain appeared at the central part of weld and the tensile strain appeared at the junction of base material and weld. The deformation was of upward warping, which is helpful to explore the numerical simulation of welding structure.

In the reinforcement of coal gangue slope treatment, it is difficult for hole and construction with traditional method, self-drilling anchor method was adopted, Slope stability safety factor was calculated with slope stability analysis software under coal gangue slope and self-drilled anchor reinforcement coal gangue slope, and finally the anchor pipe processing technology, construction methods and the production of grouting process and framework were introduced, which provided the practice for similar engineering.

Based on the analysis of features and NC-machining process of typical slots,a rule for slot-defining is given.An algorithm for toolpaths’ generation is proposed in the paper,via automatically obtaining the driving information of slot features.On these basis,under the environment of VS2010,a feature-based NC-processing system aimed at slots is developed,by which NC program can be made automaticly.At last,a simulate-actual processing test is done.The result shows that the algorithm proposed is correct.

This document discusses the physical properties and chemical properties of pectin capsules, which are extracted from waste peel, and make compare between pectin capsules and the gelatin capsules from the current market.

In this paper, we find that factors which affect energy consumption are steel ratio coefficient and process energy consumption by analyzing energy consumption of every process in integrated steel works. On this basis we point out the main reason for the high energy consumption of iron and steel industry in China is that integrated steel works examine the production process without system energy saving ideas. Therefore we propose the countermeasures of energy saving in iron and steel industry in China in aspects of energy management and control center, iron-making system, steel-making system, steel rolling system, as well as secondary energy recovery, which is aimed at providing a way for energy saving and emissions reduction of iron and steel industry in China.

Horizontal well technology has become an important technological means for offshore oilfield exploitation, but at present, most of the fracture parameters optimization of horizontal well fracturing are based on the single wells productivity after fracturing and pay less attention to consider the impact of injection wells.Therefore, aiming at injection and production development mode of BZ oilfield horizontal wells after fracturing, Integral fracturing physical model and productivity forecast mathematical model of horizontal well for the purpose of improving integrated exploitation benefit of the block is established respectively.Combining with reservoir parameters of BZ oilfield, a corresponding numerical simulator is developed by means of solving mathematical model to forecast production performance of oil well with different fracture number, fracture length, fracture conductivity. The best fracture parameters are obtained through analyzing the effect of fracture parameters on accumulative oil production, which provides theoretical foundation for integral fracturing optimization design of horizontal well of BZ oilfields, and has vital site guiding significance.

The tight sandstone formation usually has natural fracture, which is the foundation of effective development using hydraulic fracturing. The conventional reservoir productivity simulation method don't adapt to it. In this paper, Warren & Root model was used for describing infinity tight fractured reservoir model with vertical hydraulic fractures. Then, assuming the fracture length and the width does not vary with time and formation pressure, fracture seepage equation was obtained in base of the one-dimensional flow Darcy percolation equation and continuity equation. By Stehfese, a method of numerical inverse transformation, production performance simulation model was established for natural fractured tight sandstone reservoir. Taking for actual example from Daqing oilfield, affection of characteristics of natural fractures and artificial fracture parameters on productivity of natural fractured tight sandstone reservoir were analyzed. Elastic storability ratio has a greater influence than interporosity flow coefficient. It was the core technique for the gas reservoir to effective development by large amount of fluid and low sand ratio.

For high-wind-speed wind power development and problems, propose development and application of low-wind-speed wind power (LWSP). Analysis of the characteristics of LWSP , advantages and necessity of development and application of it. Research the key technologies of LWSP development. It ultimately lay the foundation for research, development and application of LWSP technologies.

This paper has proposed a new control algorithm based on wavelet neural network to control the Variable air volume Air Conditioning System with features of nonlinear and large lag. Using the wavelet neural network to predict the output variables online, and using the fuzzy RBF neural network as the controller to robust control the uncertainties of system parameters. Simulation results show that the algorithm proposed has good local predict ability for the nonlinear system, which is in full agreement with the mode. And it shows strong robustness and adaptability using the fuzzy RBF neural network to control the model gap in the running process of system.

A signal generator with adjustable frequency, phase and duty cycle is designed in this paper. The design of this signal generator is based on the technology of direct digital synthesis (DDS).The classic structure of DDS is presented and its principles are introduced in detail. The key modules of the design such as phase accumulator and pulse width processing are implemented by verilog HDL language. With suitable FPGA, the designed signal generator and all modules of the design are simulated successfully in Quartus II.

Due to the particularity of the fracture-cavity reservoir space, the seepage theory developed from homogeneous reservoir cant be applied to predict the productivity of fracture-cavity reservoir. This paper simplified the fracture-cavity system to an oil storage vessel, and based on the basic principles of material balance, established the productivity-prediction model which was suitable for the acid fracturing horizontal well in fracture-cavity reservoir. The results showed that the productivity of fracture-cavity system was high and steady. Meanwhile, the connected fracture-cavity system had a greater contribution to increasing production capacity than other factors.

Experimental investigations were made on the instability of supercritical kerosene flowing in active cooling channels. Two approaches were used to control the pressure in the channel. One is the back-pressure valve while the other is the venturi. In both conditions, a kind of low-frequency oscillation of pressure and temperature is observed. And the oscillation periods are calculated. By comparison with the flow time, it is concluded that the instability occurred in active cooling channels is probably one kind of density wave instability. And its period has no relationship with the cooling channel geometry, nor the pressure, but only depends on the flow time of kerosene in active cooling channels. When the mass flow rate, density and pressure drop couple with each other, the density wave instability will appear.

The game of international energy is the inevitable choice for China’s energy security strategy. By using the basic principles of the game theory, defining the connotation of the energy security game at fist, and then according to the different of the energy activity behavior, proposing the energy activity game relationship between three categories-the energy production countries, energy consumption countries, energy production countries and consumption countries, from which we select the various bodies in the international energy market, such as the United States and Russia, which have obvious conflict with our country to make energy game analysis, to explore the Sino-US energy competition model and the Sino-Russian energy competition model, to clear strategic orientation of Chin’s energy security on the whole, and to find out the right path of China’s energy game.

Developing the eco-tourism in low carbon economy has becoming an appeal for all sectors of the society. To develop a low carbon economy, as well as construct low carbon cities, is a convenient and scientific way to starting from the construction of low carbon scenic spot, this concept should put deep into the exploitation and construction of scenic spot. As direct participants of tourism activities, tourists have no doubt play a key role in the construction of low carbon scenic spot and achieving the goals of low carbon in scenic area. At present, low carbon tourism is in fact more to reflect a kind of energy conservation and emission reduction in concept, for which it is a response to ecological tourism and sustainable tourism. There has no specific and quantifiable index to qualify as the measurement and evaluation standard of low carbon scenic spot. It is thus clear that to construct low carbon scenic area that we should put forth effort to strengthening tourists’ low carbon tourism consciousness.

Gravels and natural fractures in glutenite formation have significant impacts on fluid loss when hydraulic fracturing is conducted. Matrix permeability and porosity were computed through Kozeny-Carman equation when gravels contents and size are known. Then a pebbly dual permeability dual porosity model was used to quantitatively evaluate the fracturing fluids loss in glutenite formation. Filtration rate curves could be plotted from the pressure distribution function which was obtained through orthogonal transformation method. Different gravels contents and multi-size-gravels were taken into accounts in this paper. The results show that both filtration rates in matrix and natural fractures decrease with increasing gravels content in matrix; and the filtration rate in matrix decrease much more. Impacts of gravel content are more significant than impacts of gravel size. Natural fractures have much more significant impacts than gravels.

Polylactic acid as a biodegradable polymer shows relative high rigidity, but it is brittle and has poor heat resistance, which greatly limits its application. The goal of this experiment is to prepare polylactic acid/organic modified montmorillonite nanocomposite by melting, and to enhance the material properties by improving the interfacial compatibility. First PLLA-g-MAH is prepared through reactive extrusion under initiator dicumyl peroxide, then PLLA /PLLA-g-MAH/OMMT nanocomposite is prepared by melt extrusion. Grafted rate was determined by infrared spectroscopy and chemical titration, and it get to peak when the content of maleic anhydride is 2 wt %. Melt flow rate indicates the nanocomposite has better melt flow and better workability than pure PLA. Mechanical properties of the nanocomposite are best when the content of grafting is 3 wt %. DSC shows that melting temperature and crystallinity of PLLA first increase and then decrease along with the increase of the PLLA-g-MAH, and both of them come to the top when PLLA-g-MAH is 3 wt %.

To enhance the crystallizability and flexibility, Poly L-lactide (PLLA)/ Talc/ tributyl citrate(TBC) composites were prepared via melt extrusion and investigated by thermogravimetry (TG) and derivative thermogravimetry (DTG). It was shown that the thermal decomposition temperature of PLLA/Talc (97:3) and of PLLA/Talc/TbC (96:3:1) had increased 7.6 oC and 16.2 oC respetively compared with pure PLLA. The thermal decomposition kinetics of pure PLLA and composites were studied by using the Ozawa–Flynn–Wall (OFW) and the Friedman methods respectively, the results indicated that the apparent activation energies of PLLA/Talc/TBC composites increased sharply in the initial stage of the mass loss.

HDPE/E-TMB and HDPE/E-SMB blends are prepared by thermal mechanical blending of toughening master batch (E-TMB) with HDPE and simple blending master batch (E-SMB) with HDPE, respectively. The difference of the melt flow rate between HDPE/E-TMB and HDPE/E-SMB blends was studied. The effects of the elastomer ratios and the ratios of matrix resin to elastomer of E-TMB, the types and the amount of anti-crosslinker of E-TMB, the elastomer content of HDPE/E-TMB blends on the melt flow rate (MFR) of HDPE/E-TMB blends were discussed.

Based on limit equilibrium method, the subgrade stability formula under rainfall infiltration is derived and the influence of matric suction on subgrade stability is analyzed using the safety coefficient formula. What’s more, the affection of rainfall intensity, duration and soil permeability on subgrade stability is studied and the influences is obtained. The presented research provides the theory basis to controlling of rainfall infiltration.

HE1/E-TMB and HE2/E-TMB blends are prepared by thermal mechanical blending of toughening master batch (E-TMB) with 2200JHDPE (HE1) and 5000SHDPE (HE2), respectively. The crystalline morphology of HE1/E-TMB and HE2/E-TMB blends were studied with polarized light microscope (PLM), and compared with those of HE1/E-SMB and HE2/E-SMB blends. The results showed that the crystallite size of HDPE/E-TMB and HE/E-SMB blends was remarkably smaller than that of the pure HDPE, while the number of the crystals increased. At the same elastomer content, the refined extend of the crystallite of HE2/E-TMB blends obviously increased than that of the HE1/E-TMB blends. The number of the crystal gradually increased and the crystallite size substantially reduced with the elastomers ratio (M/N) increasing. The refined extend of the crystallite of HDPE/E-TMB blends gradually enhanced and the number of the crystal substantially increased as the elastomer content gradually growing.

This paper select the appropriate calculation and analysis models and examples, using finite element analysis software ANSYS to compare and analyze the dynamic properties of three large space shear walls of different thickness. The result indicated: the effects of the large space shear wall structure to torsion with the increase of wall thickness.

Fluid-solid coupling dynamic characteristics analysis of vertical cantilever lifting pipe in transporting coarse solid particles was conducted by adopting ADINA. Firstly, finite element models of pipe and fluid were built, which was solved by using ADINA/FSI module. Secondly dynamic characteristics of pipe vibration for different run-time, constrain conditions, volume concentration and transporting velocities were studied. Thirdly the stress and displacement characteristics were discussed under above conditions. The results were shown that stress and displacement will increase with transporting concentration and velocity rising; the shorter run-up time is, the bigger stress and displacement will be; stress and displacement of lifting pipe supportive anchor in weak constrain were greater than that in fixed connect condition. Analysis results have certain directive significance in future structure design, check, reducing vibration study for lifting pipeline in the ocean mining.

This paper aimed at NC system’s high-speed, high-accuracy, high reliability requirements. The condition monitoring, faint information extraction and fault diagnosis technology are researched of complex CNC system. Elaborated to develop a common interface and achieved the seamless interaction of CNC system and reconfigurable embedded monitoring unit basis. A machine tool monitoring diagnostic verification platform with on-machine monitoring and intelligent maintenance features of CNC system is constructed based on the internet. Integration achieved the CNC machine tools’ status remote monitoring and fault diagnosis, and detailed analysis of the key technologies for the components of the system. Through effectively integration of the computer technology, weak signal extraction technology, fault diagnosis or other technologies to enhance the automation, networking and intelligent level of the complex CNC system.

Modal analysis of a simply supported beam with elastic support in vertical direction was conducted. Based on Bernoulli-Euler beam model, the first three nature frequency equations and the vibration mode function were obtained. And with different stiffness in vertical direction, the nature frequency equations were solved using numerical method, at the same time, curves of the relationship between support stiffness and nature frequency were acquired, and the corresponding functions were fitted with least square method simultaneously. Based on a typical beam structure, the accuracy of the functions was validated using finite element method, and the relative error was less than 3%.

In order to find the machine fault and take adaptive measures to deal with it accurately and in time for machine equipment fault diagnosis, a portable data-acquisition and signal analysis instrument based on Qt is introduced, which plays an important role in mechanical industry. Qt is a tool which is used to build multi-platform graphical interface in the way of "written once, compiled anywhere”. The factors which make Qt outstanding in most programming tools are the availability of source code, help documentation and high-class technical support and so on. In this paper, how to develop the software of portable data-acquisition and signal analysis instrument is discussed in detail.

In this paper, pan-Boolean algebra for PID control concepts, methods and principles is proposed based on theory of Pan-Boolean algebra, Take the deviation of the control system, of the deviation, integral of the deviation as a pan-Boolean algebra PID controller’s input, for the different characteristics of the object and design of different control rules, we can get pan-Boolean algebra PID control algorithm; according to the system Indicators requirements, calculating simulation and optimization design of control algorithm parameters to achieve optimal control for system. The paper also proposed a three-dimensional coordinate system described method for system output response or the control parameters and deviation, deviation differential or deviation integral, this is a profoundly new tool for control system’s moving process features. The paper is important for PID control and application.

In a high-speed rotor system, vibration control is necessary to ensure steady operation of the system. Magnetic damper is one of the effective means to control the vibration. This paper is concerned with the optimal design of a passive magnetic damper’s system parameter, including its geometric and electrical parameters. The relation between the damper’s system parameter and its damping coefficient is derived. A mathematical model that maximizes the damping coefficient is built, with the constraints of the geometric and electrical parameters. The optimization program is based on the algorithm of sequential quadratic programming method. The program yields the maximum damping coefficient under the given condition of the rotor’s diameter.

In this paper, the basic theory of Virtual Design was described and the application of 3D design software SolidWorks 2009 in loader working device was introduced as well. In SolidWorks 2009, Loader working device was taken for example to discuss the process of parametric modeling. Meanwhile, it could be approved from the virtual assembly process of working device that the whole process was fully in line with the assembly process in actual production.

This paper describes a computer-assisted approach that integrates flowline layout design and functional layout capacity planning. In this layout problem of flow manufacturing, the parallel arrangement of the flowlines allows the placement of linear material handling aisles between pairs of adjacent flowlines. An algorithm based on longest common subsequence analysis is proposed and validated using a case study. At the same time of layout planning, the need for machine duplication is examined with capacity constraints.

Safety and reliability of liquid ammonia storage tank is very important. The stress of manhole is high and complex, so it is necessary to analyse welding stress of manhole of liquid ammonia storage tank. This paper ignored the complex process in the weld pool, simulated complex thermal process in weld pool by continuous conductive welding heat source, deduced the calculation formula of maximum stress by establishing Gaussian heat source model of carbon dioxide welding, and modified stress exponent k of cylindrical pressure vessel. This new method has a positive meaning for welding stress analysis of pressure vessel.