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In order to evaluate the risk degree of the tailings pond’s dam-break disaster reasonably, according to statistical analysis of the tailings pond’s dam-break failure and "the tailings major hazards classification method" of our country, the improved "index weight method" is worked out, and the index partition method and weight assignment of the "index weight method" are analyzed and researched detailed. Combining with an engineering example to verify the improved "index weight method", and the sensitivity of index weight is discussed. The results of the analysis show that "index weight method" for the judgment of the risk degree of the tailings pond’ s dam-break disaster is more reasonable. It is more feasible for safety department to make division of attention to supervision level of the tailings pond according to the determination results.

In the process of high sulfur gas field development, the sulfur will separate out from the mixed gas when the pressure near wellbore area drops to a critical pressure of H2S. This will reduce the reservoir porosity greatly and decrease the gas well productivity as well. This paper discusses the characteristics of pressure transient testing plots when sulfur deposition occurs based on the redial composite reservoir model. And introduce an approach to determine the sulfur deposition radius near the wellbore with pressure transient testing interpretation in high sulfur gas reservoir. The method has been applied in some high sulfur gas field in eastern Sichuan Basin. The result shows that the method is simple and practical.

To solve the problems such as randomness user behavior, effective privacy protection and massive data processing shortage, this paper has proposed a household load data processing method with privacy protection, combined data mining and cloud computing. First, it gave the platform architecture and individual protection model. Then, it proposed Mask-k_means database encryption method, algorithm parallelization was implemented by MapReduce. Finally, this paper varied the method was and implemented household load data processing based on statistics and real-measured data respectively. One conclusion is that feasibility of cluster analysis for multi-user was low, while single-user load analysis is high. The other is that this method is simple and practical. This can provide a new way to household load big data under smart electricity consuming.

In this paper, the substation computer supervisory control system structure, content, features and characteristics were described. In recent years, substation monitoring technology has been developed rapidly, and has been widely used. However, due to the promotion of our country is in its infancy, technology is not mature, the new operation and management model is being explored, and thus in the operation also exposed some problems.

Phase change thermal control technology has gained increasing focus as an emerging technology for the thermal control of spacecraft. This literature focused on melting process inside a latent heat energy storage filled with phase change material (PCM) by numerical simulation. A matrix-based enthalpy porosity theory in a three-dimensional finite volume discretization is simulated. The temperature distribution during the melting process of PCM Cerrolow-136 and CH3COONa·3H2O is obtained, based on which the thermal control function and energy storage capacity is compared. The results show that Cerrolow-136 has better performance. In different states of phase change, the temperature distribution of Cerrolow-136 is fairly uniform. Thermal control face's temperature of Cerrolow-136 is closer to phase transition temperature. In the same heat flux of 3000 W/m2, The whole process of thermal control temperature getting to 80°C for Cerrolow-136 is longer. Cerrolow-136, for its excellent characteristics, has potentially broad application in the fields of latent heat energy storage and space vehicle electronics.

The internal-mixing twin-fluid atomizer has found wide application in aerospace, industrial gas turbine, oil-fired boiler, energy field and so on. The atomization characteristics of internal mixing nozzle under different operating conditions are studied by utilizing the Malvern laser particle size analyzer. According to the experiment results, the influence of air pressure, hydraulic pressure and air-liquid ratio to droplet size and uniformity are analyzed. The three-dimensional flow field model of internal mixing nozzle is built to simulate the droplet size of mixing room and outlet by Fluent. The simulation results show that the droplet size decreases along with the increase of the air pressure and the air-liquid ratio, moreover, the air pressure plays a main actor. The droplet size increases in the mixing room, and then decrease sharply at the domain of the outlet. The droplet size of the nozzle’s outlet obtained in simulation matches the experimental result.

The optimal scheduling of crude-oil operation in refineries has been studied by various groups during the past decade leading to different mixed integer linear programming or mixed nonlinear programming formulations. This paper presents a new formulation with oil residency time constraint based on single-operation sequencing (SOS). It is different from previous formulations as it considers oil residency time constraint and pipeline transfer and does not require to postulate the number of priority-slots in which operations take place. This model is also based on the representation of a crude-oil scheduling by a single sequence of transfer operations. A simple MILP procedure has been used to solve this model leading to an satisfactory optimal result.

Disaster Rescue Robot is a small caterpillar robot used for carrying first aid articles, reasonable shock-absorbing system is an indispensable part to reduce the rush of the ground because it has to plummet from a certain level to the ground when it works. We use the method of modular design in this article and design the landing gear based on the performance of conical spring in order to absorb some of the forces during a fall. Then the three-dimensional modeling software is used to establish the parametric model of the robot shock-absorbing system to provide an effective way for the design of the Disaster Rescue Robot.

Aiming at problems of test, layout and application about campus network and combining with fundamental characteristic, introducing primary technology about transition from IPv4 campus network to IPv6 one, This paper discusses the status of IPv6 support technology and presents basic concept that campus network can be formed Gradually through layout testing network and experimental network; At the same time, in order to offer practical technical reference to favorable upgrading and applying campus network of ordinary universities It also discusses some services and applications about IPv6 campus network.

Automotive abnormal sound is an important manifestation of the automotive system components early malfunction. It can effectively improve safety and reliability of the vehicle system by characteristics extraction of abnormal vehicle sound and prediction of the development trend of fault. What’s more, it can solve the problem that ECU can’t identify tire failure and other problems. As a result, it will reduce the number of traffic accidents, protect human safety and property.

This article shows a composed method for modeling the concurrent execution of working processes in flexible manufacturing systems (FMS) by a special class of Petri nets named Resource Oriented Petri nets (ROPN). Essentially, the type of net comes from the availability of system resources. The analysis of ROPN is used to characterize deadlock situations in terms of full markings for certain structure named PPC. For the sake of preventing the system from deadlocks, a policy is proposed based on a series of restrictions for resource allocation, without considering the presence of unmarked siphons in Process Oriented Petri net (POPN). Finally, a control strategy of deadlock avoidance is designed for ROPN, which is better than other control policy.

0940 type cushion of E-flute corrugated paperboard is selected as the research object. By changing the load area, side breadth and the height of the cushions separately, static compression tests were done. The effects of structural parameter to cushioning property were analyzed through energy absorption method. It is useful to promote the application of corrugated board cushion.

Biscuit, as a common snack, in order to attract the children’s attention, besides its taste and shape, packaging design is equally important. The beautifully decorated surface of the box can be divided into a number of blocks (4 or 9) by setting the punch lines. After the biscuits are eaten up, tear the box along the punch lines, then it becomes a simple jigsaw puzzle. Inside the box except the biscuits bag, a cute clamp like scissors added. So the children can gripping biscuits by the clamp rather than by hand directly.

As a generalization of Fourier transform, the fractional Fourier Transform (FRFT) contains simultaneity the time-frequency information of the signal, and it is considered a new tool for time-frequency analysis. This paper discusses some steps of FRFT in signal detection based on the decomposition of FRFT. With the help of the property that a LFM signal can produce a strong impulse in the FRFT domain, the signal can be detected conveniently. Experimental analysis shows that the proposed method is effective in detecting LFM signals.

The typical working condition and potentiality of energy recovery in construction machinery are discussed. Existing energy recovery techniques in the three types of technology platform are summarized with their features analyzed.The latest engineering results of energy recovery system are introduced. A preview of possible developments and challenge is presented finally. These work will provide useful information for energy recovery in construction machinery and contribute to the development of this field.

In conjunction with theoretical heat exchange model, experimental investigations have been conducted for a coupled system of Selective Catalytic Reduction (SCR) and Regenerative Heat Exchange (RHE), to reduce nitrogen oxides (NOx) from coal-fired boilers and High Temperature Air Combustion (HiTAC) furnaces. Results indicate there is no effect of catalysis reactions on heat transfer; catalysts serve the function of heating elements. The outlet NO concentration periodically decreased in an almost linear fashion. NO conversion: i) rose slowly with a longer switching time; and ii) reached the peak value of temperature with a delay compared with the steady state. The coupled system requires less space and hence is a suitable option for SCR renovations in coal-fired power plants.

Utilizing interval number theory, this paper explores a sorting method to assess quality curriculum. Based on comprehensive analysis of a variety of factors affecting quality curriculum, using combination weighting methods of objective and subjective, we give the corresponding weight interval values of evaluation indicators. Furthermore, we give the sorting steps of quality curriculum assessment based on interval numbers, and give an application instance.

The Phenomenon of a Magnetic Controlled Ferrofluid Flow in the Flat Plate Laminar Flow System is Discussed in this Paper. the Ferrofluid Flow is One Kind of Colloid Mixture, which is Composited by the Magnetic Particles, Carrier Fluid and Surfactant. its Motion is Followed the Fluid Dynamics and can be Controlled by a Magnetic Field. from the Theoretic Analysis and the Experimental Test, the Coefficient of Viscosity of the Ferrofluid Flow will be Affected by the Magnetic Field. Thus, an Experimental Rig is Built to Test the Influences of the Gap of the Plate and the Strength and Direction of the Magnetic Field for Several Ferrofluid Flows with Different Dividing Rates of Volume. Experimental Results Showed that the Coefficient of Viscosity of the Ferrofluid Flow is Almost Not Upgrading in a Wide Gap Condition by the Magnetic Field, but as the Gap is Smaller, the Coefficient of Viscosity will be Promoted Obviously. Furthermore, Enhancing the Magnetic Field, it will be Increase the Coefficient of Viscosity of the Ferrofluid Flow. from the Experimental Results, the Relationship of the Magnetic Field, Coefficient of Viscosity of Ferrofluid Flow and the Carrier Fluid can be Confirmed.

The oil spoil detection is an important problem in many applications such as oil exploration and transportation. But in some application such as sea, this task is very difficult because of the strong clutter. Many algorithms have been proposed for this problem. The Maximum Likelihood (ML) is one of those good solutions. This paper describes an application of neural network (NN) for obtaining the global optimal solution of finding oil spoil. It improves the estimation accuracy. The computation complexity is modest.

Beginning from the manufacture process of metal rubber material, the structure and electromagnetic shielding mechanic were studied. Based on the flange coaxial test, the shielding efficiency of metal rubber samples was measured and the mathematic model of electromagnetic shielding efficiency was deduced. Using Schelkunoff formula the number and fitting curve of shielding efficiency were got. It can be concluded as a new kind of functional material, the metal rubber material would be widely used in the field of electromagnetic shielding and packing.

This paper presented a biogas-solar hybrid system and investigated the feasibility of using biogas to increase the enthalpy of parabolic trough collectors steam so as to increase the cycle efficiency and power production. High temperature anaerobic digestion (AD) was adopted to produce biogas by using corn straw, manure and sewage. Biogas fraction and energy-to-electricity efficiency were used to evaluate the biogas contribution to the electricity generation and the energy utilization efficiency based on off-design performance analysis respectively. A comprehensive levelized electricity cost (LEC) and life cycle assessment (LCA) for the hybrid system power production were performed. The simulation calculation results show that biogas utilization plays an important role in the decrease in systemic LEC and greenhouse gas emissions. Improvement is achieved in both of generation cost and greenhouse emissions for biogas-solar hybrid plant compared to solar-only plant.

Based on the traditional campus public address system is introduced in the network technology, this paper discusses the network public address system composition and function of main equipment, the implementation partition on demand, partition paging remote monitoring and remote diagnosis and remote software upgrade

Aiming at the issues of smooth transition from IPv4 to IPv6 and interoperability in technical coexistence period about campus network, discussing the technical characteristics of IPv6 protocol, GNS3 and OPNET simulator, combined with the status of weakness of IPv6 technology, lack of IPv6 technology planning and financial support for network upgrade in the vast majority of colleges, adopted the simulation methods to build a network model of IPv4 and IPv6 to achieve the technologies study such as topology design, network configuration and testing, network performance design and evaluation of IPv6 campus network under the low-cost conditions.

This paper proposes a addressable digital broadcasting system that can use different frequency/time/coding segmentation implementation zoning control and program delivery. It uses coaxial cable transmission, to achieve 16 sets of different programs and Can overcome conventional broadcasting system can only use a space partition implement partition control defects.

Considering the shortcomings of H.264 rate control algorithm, the paper proposed a new frame level of rate control algorithm according to the movement activity of each frame. xperimental results showed that compared to JVT-G012 which adopted rate control algorithm,the proposal can control the rate more accurately and obtain the higher PSNR and visual quality.

By numerical and experimental methods, heat alternating magnetic treatment of diamond agglomerations were researched, the microstructure and mechanical properties before and after treatment were also analysed comparatively. The numerical analysis shows: the alternating magnetic field stress is bound to make solid-state microstructure change, this intensified magnetic shock can broke dendrites and tangles organization within the organization and enables organization uniform, dense. The experiments indicate: After heat alternating magnetic treatment, the HRB hardness of test pieces matrix is improved 4.34, impact toughness enhanced more than 25%, matrix organization became uniformity and density. Results revealed that alternating magnetic treatment can be an effective method for improving the performance of the diamond agglomeration.

On-line monitoring recognition for machining chatter is one of the key technologies in manufacturing. Based on the nonlinear chaotic control theory, the vibration signal discrete time series for on-line monitoring indicator is studed. As in chatter the chaotic dynamics process attractor dimension is reduced, the KolmogorovSinai entropy (K-S) index is extracted to reflected the regularity of workpiece chatter, then the k-S entropy is simplified by coarse - grained entropy rate (CER), which can easily evaluated as chatter online monitoring threshold value. The milling test shows that the CER have a sharp decline when chatter occurre, and can quickly and accurately forecast chatter.

Concrete crushing of the municipal engineering by traditional broken tools has flaws of inefficient, high dust pollution, high noise, high labor intensity. Hydraulic crushing equipment with ultra-high pressure water jet is designed, which includes the ultra-high pressure five-plunger pump unit and its control system. Engineering applications show the equipment owns characteristics of high efficient, cold state, security, and cannot produce stratified thermal aggregation, heat-affected zone in concrete and dust pollution. Then qualities of concrete hydraulic crusher in a complex environment are improved effectively. It provides an effective method to solve the problems of concrete hydraulic crushing.

The theory, model and algorithm of three products heavy medium cyclone flow field were researched, and the heavy medium cyclone flow field was simulated based on aerodynamic. Through the researches, the numerical discrete algorithm of heavy medium cyclone flow field was deduced, the calculation algorithms of heavy medium cyclone flow field were given, the washed coal particle trace, intermediate coal particle trace, gangue particle trace in three products heavy medium cyclone, and the separation rules based on aerodynamic and flow field characteristics of three products heavy medium cyclone were obtained.

Due to enthalpy-porosity technique, mathematical models of phase change material (PCM) and foam composite phase change material (FCPCM) in two-dimensional rectangular canister were established in the conditions of gravity and natural convection. It solved phase change problems by the enthalpy method coming from computational fluid dynamics. The numerical results show good agreement with reference findings. The numerical comparison between PCM and FCPCM verifies that metal foam can not only enhance the thermal conductivity of the PCMs but also improve the thermal performance of the heat storage system.

This paper studies the math functions about non-sinusoidal vibration waveform of the continuous caster, simulates the continuous caster non-sinusoidal vibration waveforms displacement and velocity curve ,and creates a model of the mold oscillation control system. Besides, we use MATLAB to judge the stability of the control system and system simulation and verify the feasibility of the control system through the field's test.

In the paper, the main structural of the bucket wheel stacker reclaimer was designed based on Virtual Prototype Technology. Firstly the bucket wheel stacker reclaimer was built by using 3D design software Solidworks. Then the static analysis of the main structure was done by using FEA method. Then the motion simulation was finished by using Adams, and the velocity curve was described. In the paper, the main structural design and motion simulation was done efficiently based on a series of Virtual Prototype Technology such as parametric modeling, FEA method and motion simulation. The superiority of virtual prototype technology in the design of large engineering equipment is obvious.

Bucket wheel stacker-reclaimer is widely used in the field of material engineering machinery. Because of its working environment is very bad, it has higher requirements on its safety and reliability. Wind load calculations are necessary to ensure of the Static mechanical behavior. This paper mainly studied the main steel structure in a condition of no-load and maximum load work conditions and add the effects of the wind whose speed is about 20 m/s, At last all the stresses and strains were calculated based on FEA method.

A method is proposed to predict the handling and roll properties of electric drive mining trucks and evaluate their safety status. Trucksim is used to simulate the truck dynamics and Simulink is used to model the electric drive system, the truck model takes a double-lane change manoeuvre according to ISO 3888-1. A 190t mining truck is demonstrated and the understeer gradient and roll angle results respect its safety status well. Using this method, mining truck designers could make the handling and roll prediction before manufacture and modify their design.

Magnetic properties of 6H-SiC doped with transition metal (TM) atoms are calculated using the density functional theory method (DFT). It is shown that TM doped in a 6H-SiC host may have both magnetic and nonmagnetic states. From the figures of their density of states (DOS) and partial density of states (PDOS) and to compare the energy differences between ferromagnetic and nonmagnetic states, we demonstrate that Cr and Mn-doped 6H-SiC emerge a half-metallic ferromagnetic state, Co and Ni-doped 6H-SiC create very little magnetic features, while Fe-doped 6H-SiC is in the nonmagnetic state. We also calculate the energy differences between ferromagnetic and antiferromagnetic of Cr, Mn and Fe-doped 6H-SiC in the doping concentration (8.34%). It is found that the energy of the antiferromagnetic state is lower than that of the ferromagnetic state.

Bucket wheel stacker-reclaimer is kind of a typical multi-rigid-body system. Its main steel structure consists of bucket wheel, forearm frame, column tower, balance frame and pull rod, etc. All components connected with each other basically by welding. And the integral structure can realize whole luffing motion and turning motion. Reclaiming arm, central bracket and pitch steel structure of counterweight arm are the structure of its core. This paper use ANSYS to create the simplified finite element model of the steel structure and analyze the distribution of loads in all types of conditions. Loading solving, then cloud picture of displacement and that of stress of the overall luffing mechanism was concluded, so as to check the carrying capacity and strength of the structure.

The vibration mode of main steel structure of bucket wheel stacker reclaimer is complex and changeable, so its modal analysis is necessary. In this paper, the main steel structure of bucket wheel stacker reclaimer was integrally designed and its main parameters were determined. then the finite element model of the main steel structure of the bucket wheel stacker reclaimer was established and the modal analysis was simulated, finally the results of its inherent frequency were calculated by FEA method.

This paper used the finite element method to compare the mechanical properties of two different configuration counterweight booms of the bucket wheel stacker reclaimer. And two different forms of the finite element analysis model of the counterweight booms were built in ANSYS. The stresses and strains under its working state were calculated. Then the impact of the counterweight arm to the force and stability of the whole rack could be analyzed. The results of this analysis provided a basis to select different types of the counterweight booms in different environment, and it has an important guidance and reference significance to the design and analysis of counterweight booms of large-scale machinery.

In order to simply the design process and reduce the cost, a virtual prototype of spreader was built in this paper, which was used to simulate the operating condition of spreader in the open coal mine. Then the method of test and verification in engineering application is put forward. Finally, it obtains the parameters of system model of spreaders that satisfy the requirements in actual operating condition by analyzing the test results. The results indicate that the virtual prototype could simulate the real condition and provide exact data for the stable operation and maintenance of spreaders.

Discussion of two classic space-time-frequency coding (STFC) scheme in frequency selective channel transmission problems is given. One utilized the data order inversion and conjugation transform, which makes the quadrature data encoder can no longer be interpreted as orthogonality of channel parameter matrix. Another has data orthogonal pre-processing, which makes each symbol spreading stream uniformly to all sub-channels. The computer simulation results illustrate the theoretical analysis of the paper.

In this paper, the Indium Tin Oxide (ITO) thin films were prepared by a sol-gel dip coating method and then annealed at 600°C under different atmosphere (vacuum, N2 and 96.25%N2+3.75%H2). Their microstructure, optical and electrical properties were investigated and discussed. Suitable atmosphere can improve the crystalline of the ITO films, therefore the optical and electrical properties of the ITO films are improved. The uv-vis results showed the maximum of transmittance in the visible range (380-780 nm) of 85.6% and the lowest resistivity of 4.4×10-2 Ω-cm when the ITO films were annealed under 96.25% N2 with 3.75% H2 atmosphere.

As the construction technique of cement-soil composite piles is winning general popularity in building industry, the development of new types of piling machines has witnessed a growing trend in China in recent years. In the paper, a mechanical analysis for a piling machine column is conducted, based on the virtual prototype proposed in a previous portion of our research work in this area. To obtain the stress distribution at certain interesting locations of the column, working conditions are defined. In accordance with the simulation results, optimum design is carried out for the joint between the column and the tension diagonal, as well as that between the column and base frame. Finally, the strength adequacy of the vertical column is validated. With the optimum method, the design cycle of piling machine is greatly shortened and the analysis cost decreased.

Free-piston Stirling engine is considered to be the most novel and revolutionary Stirling configuration. Schmidt analysis is used to describe the physical model of free-piston Stirling engine and to drive the formulation about thermodynamic parameters. The performance of free-piston Stirling engine has been analyzed. Finally it made a comparison between analysis calculation, experimental and numerical results.

On basis of considering influence of rigidity, elastic module, unit weight and section area etc conductor parameters on the jumper conductor, establish the mathematic model of the jumper conductor on basis of Cosserat bar theory, operate MATLAL and call VC++ Compiler to complete research and development of the jumper conductor length calculation software. Through test simulation of the jumper conductor and Xiangjiaba -Shanghai ±800kV DC engineering application, calculate sag and design sag with software which have good consistence, reduce high height operation time and reduce waste of jumper conductor, realize the standardized design and construction of the jumper conductor, which has good application prospect.

Reuse the electric vehicle batteries as a means of battery storage, could extend the battery life cycle. In order to improve the battery charge and discharge balance, we introduce and compare two optimized classification methods. The introduction of battery storage system in electric vehicle charging station could solve peak shaving, power quality and emergency charging effectively

Charging infrastructure is the fundamental conditions of electric vehicles(EV)’s application and dissemination, and advanced charging standards can guide and regulate the harmonious development of EV and infrastructure. In this paper, plenty of and latest EV charging standards were collected at home and abroad, which were compared in different classifications, then the standards differences were analyzed in term of relative merits to provide reference for the future development of EV charging standards in China.

The paper mainly introduced research state of coal mine mobile refuge chamber and its outside environmental monitoring system, analyzed particularity of chamber-outside environment and design requirements of outside environmental monitoring system for coal mine mobile refuge chamber, and put forward design goals and idea of software design, hardware design and protective device of outside environmental monitoring system for coal mine mobile refuge chamber. It put forward a design scheme of outside environmental monitoring system for coal mine mobile refuge chamber according to the actual applications and design goals. The design scheme consists of software, hardware and protective device. And it detailed expounded environmental monitoring system’s working principle, signal transmission principle and workflow. The paper can provide technology reference for development of outside environmental monitoring system for coal mine mobile refuge chamber in China.

With the continuous improvement of China’s construction technology, the application of mass concrete structures is increasingly popular in various structures in order to meet the requirements of structure and function, such as tall buildings, dams, railways and highways. There are all kinds of cracks in construction process because of the big cross section. There are many reasons to form cracks, but temperature is the most common cause. It is vital to the construction quality of mass concrete that the hydration heat, especially the peak value of temperature rise, is calculated in advance and precautions are implement in construction process accordingly. In this article, the calculation formula modified is derived through analyzing the common calculation formulas of mass concrete, the actual measurement results and the influencing factors of temperature rise.

The present work focused on developing a rapid estimation of carbon storage of single tree in urban community greening that is an important carbon storage field. The carbon storage is determined by the total biomass measured by getting carbon content percentage and density values of plants. Having surveying and calculating carbon content percentage, volume density and carbon storage of four main kinds of trees in eight residential areas, the value of computing carbon content percentage, volume density are 0.5 and 0.5×103kg/m3, respectively, agreeing with their default value 0.5. The developed carbon storage formula is applicable to computing single arbor green vegetation of cities. The carbon storage biomass of Cinnamomum camphora is the largest among the four kinds of main trees (Cinnamomum camphora (L.) Presl.), acacia (Albizia julibrissin), magnolia (Magnolia Grandiflora Linn.), laurel (Osmanthus fragrans. The results show that the calculation method is applicable and can be expanded for extensive use.

A new method to get flow rate from a float flow meter automatically by image processing technique is put forward. Images of float flowmeters which are captured by a camera link are cropped, strengthened, filtered and binaried by certain pre-processings. Firstly, one-dimensional array is generated by the binary-picture. An accumulation by its columns and averaged the peak formed by the accumulation is made. Finally, the accurate position of the float can be recognized. Some simulation experiments show that the resolution of measurement by the image technique can be 1/10 of the minimum scale of glass float flowmeters. Some errors which include the angle of elevation and depression caused by cameras are discussed.