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Micro-grid gives full play to the advantages of distributed power supply by low pollution and flexible power supply form. Micro-grid has good economic benefits and social environmental benefits. Core technology of Micro-grid, policy support and grid-connected mechanism are problems encountered in Micro-grid construction and operation. Based on the analysis of development situation on the Micro-grid operation, this paper classifies the Micro-grid investors. According to the main purpose of different investors, this paper analyzes the cost structure and income structure of Micro-grid operation. And on this basis this paper proposed the corresponding optimal objective function under different Micro-grid operation modes.

Geological structure health in mountainous area substation is complex, and the climate is changeable, it is easy to appear the geological disasters like landslide and subsidence in substation, Aiming at the strong electromagnetic interference in substation and other factors, to monitor of slope surface strain of mountainous area substation with FBG strain sensor, in order to reflect the stability of the slope. Combined with the actual situation of slope of Yunnan 220kV mountainous area substation, the surface type FBG strian sensors are installed on the surface of upstream and downstream slope of mountainous area substation, the lower reaches of the substation, the serial network forms a quasi distributed optical fiber sensing network. they form a quasi-distributed optical fiber sensing network through the serial networking methods.When the slope surface occurs deformation due to the soil sliding, it will drive the FBG strain sensor and transfer the equal strain to the FBG strain sensor. By measuring the center wavelength shift of the FBG strian sensor, the strian value of slope surface at each point can be reflected. The monitoring results show that, the period from May 9th to June 6th, the maximum strain of upstream slope is 171uɛ, it appears at the location of marked as US4 FBG strain sensor, the maximum strain of downstream slope is 112uɛ,it appears at the location of marked as DS1 FBG strain sensor.

Small current grounding power system is widely used in overhead transmission line in medium voltage distribution network in China. Because of its long lines, branch, space truss structure is complex, low level of automation, It is easily influenced by outside force and the natural environment, and single-phase grounding failure rate is high. It is an important topic to quickly and accurately detect the location of the fault line, and improve the reliability of power supply and distribution system.This paper has carried on the induction and the comparison of various fault detection and location method of overhead transmission line which is currently used in single phase to ground, and analyzed their advantages and disadvantages,given the corresponding conclusions, provided the reference for finding out the reasonable single-phase earth fault location method or improvement.

In order to develop the control system for fully automatic molding machine which runs stable, reliable and high-automatically, its operational requirements analysis are studied deeply, based on the analysis of present research and development situation on domestic and foreign molding machine, this paper analyses its mechanical structure, working principle, hydraulic system. Finally, the author designs the FX2N PLC control system and briefly describes designing method and characteristics of hardware and software, which solves the problem: the low efficiency of domestic steel automatic stacker molding, collision quality loss and coordination of multiple devices in transit.

Graph labeling theory has important applications in coding theory, communication networks, logistics and other aspects. In Operations Research or Systems Engineering Theory and Methods, one very often use graph colorings/labellings to divide large systems into subsystems. One can use colorings/labellings to distinguish vertices and edges between vertices in order to find fast algorithms to imitate some effective transmissions and communications in information networks. In this paper we present a computational approach to the odd-graceful labelings for some olive trees.

A simple process was developed for preparation of highly photoactive Fe and S codoped TiO2-SiO2-ZnO composite film. The Brunauer–Emmett–Teller (BET) surface area results showed that the specific surface area of the composite TiO2 sample was 432.5m2g-1, while that of the pure TiO2 was 103.4m2g-1. The diffuse reflectance measurements exhibited an extension of light absorption into the visible region for the composite TiO2. The photoluminescence (PL) spectra analysis indicated that the electron-hole recombination rate was effectively inhibited in the composite TiO2. The photocatalytic activities of the TiO2 films were evaluated by the photocatalytic decomposition of methyl green in aqueous solution. The composite TiO2 film exhibited excellent photocatalytic activities compared to pure TiO2 film.

The role of bill of material (BOM) was firstly introduced. Then, the techniques of how to establish modular BOM in multi-products enterprise was analyzed to realize accuracy and just-in time delivery of materials.

A novel method based onEmpirical Mode Decomposition(EMD) is approached to process the geometry signal. The main idea is to decompose the signal into some different detail components called Intrinsic Mode Function (IMF). The key steps are as follows: First, the signal is spherical parameterization; Second it is transformed into the plane signal and sampled regularly; Third, the translated signal is processed as an image using Bid-Empirical Mode Decomposition, getting several image IMFs; Finally, invert mapping these IMFs to geometry signal and getting the geometry signal’s IMFs.We demonstrate the power of the algorithms through a number of application examples including de-noising and enhancement.

The paper mainly studied the corrosion properties of refractory weathering steel under chloride ion erosion environment. The full immersion tests on refractory weathering steel and carbon steel Q235 were conducted; and then a comparative analysis from the perspective of the corrosion weightlessness, the macro and micro morphology of rust layers have been made. Results indicated that refractory weathering steel and carbon steel corrosion weightlessness is relatively close to the early stage of corrosion, but the trend is reversed in the mid to late; refractory weathering steel corrosion weightlessness gradually decline, but the carbon steel’s is first increase then decrease. The carbon steel is mainly pitting corrosion, while refractory weathering steel develops general corrosion under chloride ion erosion environment. Rust layers of carbon steel are loose, hollow, and uneven. As the corrosion time goes on, the thickness of refractory weathering steel’s rust layers continuously thickening and the rust layers’ integrity are gradually increasing. The corrosion depth of refractory weathering steel is less than carbon steel’s; so does the longitudinal corrosion. This is because the microstructure of carbon steel is coarse pearlite and ferrite while the refractory weathering steel is granular bainite; the grain boundaries of carbon steel have more inclusions, especially MnS that is easily dissolved in chloride ion erosion environment. It is found that alloying elements Cr, Cu are enriched in the rust layers of refractory weathering steel by means of energy dispersive X-ray spectroscopy (EDS). The enrichment of these alloy elements in the rust layers improves the rust layer density, so that the uniform, dense, smooth rust layers formed on the surface of refractory weathering steel play a significant protective film to improve the substrate resistance corrosion.

Add two coupling plate between the chuck holder and three-jaw chuck, and the two coupling plate converted to a deflection angle eccentricity L. The eccentric workpiece to be machined coupling plate from A through L and the coupling plate B out on the scale to determine the minimum size accuracy of up to 0.02mm to overcome the technical defects existing processing eccentric parts , providing precise determination eccentricity , and can reset the eccentric parts machining fixture .

In refractory weathering steel cold-rolled sheet production process, the grains are elongated along the rolling direction, which will lead to the change of mechanical properties of sheets. Recrystallization annealing is an important process in the production of cold-rolled sheets. Therefore, research on recrystallization temperature and determining the recrystallization annealing time are important for the production of cold-rolled sheets. By measuring the hardness at different annealing temperatures and metallographic structure observation, obtained the refractory weathering steel of reduction rate of 66.7% recrystallization temperature is 650°C; By measuring the temperature of 700°C hardness under different annealing time and metallographic structure analysis, when recrystallization annealing time is 1 hour plasticity and strength of cold rolled sheet fits well, with excellent comprehensive mechanical properties.

this paper gains information about the method and deficiency of center lathe processing multiple thread from the aspect of processing, discusses the common method of numerical control lathe processing multi-line triangular thread from the aspect of programming, and provides reference for solving the problem on difficulty in the numerical control lathe processing multi-line triangular thread.

In order to implement the target-controllability and the optimal dispatch of automatic generation control (AGC), a new dispatch method of AGC regulation capacity based on the multi-target optimal technology and the genetic algorithm (GA) is proposed. In the algorithm, the control factors are introduced by applying multi-target mathematical model. So it can control every object importance artificially according to the region of the area control error (ACE) by operators. The genetic algorithm is used to get the optimal results. Finally an example is given to demonstrate the validity of the proposed method.

The Ag nanoparticles was prepared by reduction of silver nitrate with sodium citrate, and the APS monolayers was self-assembled with 3-Aminopropyltrimethoxysilane (APS) on the monocrystalline silicon surface. Then, Ag/APS molecular self-assembled film was formed with Ag nanoparticles and APS membrane by liquid method. The chemical structure and morphology of the Ag nanoparticles and self-assembled film were investigated by AFM, XRS and IR. Meanwhile, the friction performances of self-assembled film was also investigated. The results shown that the Ag nanoparticle have the morphology of spherical particles with an average particle size of ca. 65 nm in diameter which were successful assembled on the surface of APS film and partially oxidized into Ag2O. The friction coefficient of the Ag-APS molecular self-assembled film has been decreased with the assembled time extened while the wear rate has improved.

Contamination of groundwater and soil by petroleum hydrocarbons is a widespread environmental problem. In order to quantify the potential of natural attenuation of groundwater at a petroleum contaminated site. The total petroleum hydrocarbons (TPH) concentrations of 11 rounds were collected during the 1 year monitoring period, and the mass flux technique is used to calculate the attenuation rates. The calculated attenuation rates are between 0.0046-0.0064d-1, which indicating the time to achieve the remediation goal for the contamination site is possible within 3 years by natural attenuation alone.

Considering the special load characteristics of the wheel loader, thispaper focus on compiling the load spectrum of the transmission of the wheelloader using the nonparametric statistical extrapolation method (NSEM). In thisprocess, the determination of the kernel function shape is the critical issue,which has been discussed in detail. Before extrapolating the sample loadspectrum, the signal denoising of the field-tested time-history load signals isperformed. After that, the sample load cycles are obtained using the rainflowcounting method and the corresponding kernel function shape is determined. Thenthe NSEM of rainflow matrix is proposed, by which the whole-life load spectrumis estimated. The proposed extrapolation method can well realize the estimationof the load cycles that do not appear in sample load cycles but may exist inthe whole-life load history.

The aim of the research is to study the changes of soil properties during the process of wetland restoration, and evaluate the results or effect of wetland restoration. Soil samples were collected from both restored and unrestored wetlands in Shuangtaizi estuary, and then we compared seasonal changes of soil properties in these two areas. The results indicated a significant increase of NH4-N, whereas TP(total phosphorous) declined slightly in restored wetland. In addition, significant seasonal variations of SOM(soil organic matter) and nutrients were exhibited in restored and unrestored wetlands especially in July and August. Meanwhile, we found that C/P ratio in restored wetland increased in summer and reduced in September. All these have suggested that soil properties and nutrients proportions were changed after the restoration, which would be more conductive for soil ecological function.

Thermo-mechanical experiments were carried out to study the effect of deformation speed and temperature on the behaviour of a non-quenched and tempered steel during hot forging. And an effective method for correction of friction was used to amend the tested flow stress, Meanwhile, the constitutive equations of flow stress-strain for TL1438 steel during hot forming was established based on the amended flow stress and hyperbolic sine which includes Zener-Hollomon parameter, and related parameters of TL1438 during hot forming was obtained by analyzing the data.

As an irreplaceable energy, petroleum play more and more important role in global economic development and civilization progress of human society. With the further exploration activity and development of exploration degree, it becomes more and more difficult. Under the guidance of anticlinal theory, most anticlinal reservoirs have been found and we are confronted by complicate target. However, the development of new geological theories, such as geodynamics of sedimentary basins, petroleum system, deep basin gas and hydrocarbon accumulation dynamics, lay the foundation of sustained development of exploration activity. New technique and methodology of basin analysis and modeling, description of reservoir, imagery log, supply science guarantee for sustained development of exploration activity.

In order to achieve the fault diagnostic and degradation assessment of the electro-hydraulic servo valve, a system of prognostic and health management based on the data-driven approach for the electro-hydraulic servo valve is presented. FMMEA performed in this study considered the degree of sub-components in electro-hydraulic servo valve. In order to use only five parameters to assess the cause of degradation, a physical model of the EH servo valve was built up to simulate the failure modes. The simulation results are very useful because the methods can be applied to assess the cause of degradation such as leakage, jamming, clogging and so on.

For a typical Full-hybrid electric vehicle (HEV) layout, such as Toyota Prius, the power-slit device (PSD) is a key component. Determination of volume or weight of a PSD is an important issue in preliminary design of power transmission applications. The purpose of this paper is to preliminary design of PSD gear drives by minimizing volume of gear trains. A stochastic approach Genetic Algorithm (GA) was applied to a differential-based coupling PSD design problem. Static and dynamic penalty functions were introduced to the objective function for handling the design constraints. The calculation of quadratic mean deviation and dynamic bounding parameter values such as determination of crossover and mutation parameter values were adopted to ensure the convergence of the fitness function. The optimized design method based on GA produced quite well results, which promptly supplied preliminary design parameters of gear drives for differential-based coupling PSD design.

Tandem GMA welding technology has high deposition rates and good welding quality. But the electromagnetic interference (EMI) between the tandem GMA welding arcs is the most important factor which can influence the welding quality .Via Orthogonal Experiments and variance analysis, this paper did some basic theory research of the mutual arc interference mechanism in the GMA welding. The study was carried out from three mainly aspects ,the welding arc length control mode ,the parameters of the control pulse and the optimal range parameters in high-speed welding .The high-speed camera system was used to observe the metal transfer .In this paper the researchers realized the stability work of high-speed movement of tandem GMAW welding .

In this paper, we propose a Template-Matching strategy combined with statistics in the tasks of human evaluation of NTCIR to avoid the arbitrariness of human evaluators. By practical operation and within-system checkup, the strategy helps avoid the arbitrariness of human evaluators and provides a benchmark for human evaluation of NTCIR.

This paper presents a research on skin effect’s influence on the current density distribution of Cu/barrier layer and Cu/cap layer interfaces of copper interconnects’ via vicinities. A two-level Cu-interconnect structure in different positional relationships with the ground plane is discussed. Through the three-dimensional (3D) finite element simulation of the interconnect structure, the variations of current density on three important surface areas are obtained when skin effect is significant, showing that the current density in the three surface areas near the via has been strongly influenced by current crowding and skin effect. So in many cases the influence of skin effect on via top and via bottom failures of Cu interconnects under high frequencies can not be ignored.

Under microwave radiation and using trimethyl chlorosilane as modifier, hydrophobic SiO2 aerogel was prepared through fractional hydrophobic modification and ambient pressure drying of the raw material, tetraethoxysilane (TEOS), in the process of sol-gel and acid-base catalysis. Hydrophilic SiO2 aerogels were also prepared using the microwave method and water bath heating method. The SiO2 aerogels prepared using the three methods, including their morphology and chemical composition, were analyzed and compared using scanning electron microscopy, Brunauer-Emmett-Teller analysis method, Fourier transform infrared spectroscopy, X-ray diffraction, and themogravimetric-differential scanning calorimetry. The results indicate that by adopting the microwave reaction, the specific surface area of the SiO2 aerogels was effectively increased and the structure of the internal nanoscale pores of petal-coated shape was found to exist under the dense external surface of the SiO2 aerogels. Thermal stability of the hydrophobic SiO2 aerogels prepared through fractional modification assisted by the microwave method was increased with the hydrophobic angle at153°, which showed super hydrophobicity.

Ag surface doped TiO2-SiO2 composite films had been synthesized by the sol-gel method and doping processes, in which tetrabutyl titanate (Ti(OC4H9)4) and tetraethylorthosilicate (TEOS) were chosen as the precursors and silver nitrate (AgNO3) was chosen as silver source. The experimental results revealed that the Ag surface doped TiO2-SiO2 composite film was composed of uniform round-like nano-particles or aggregates with the size range of 4–10 nm. Compared with pure TiO2 film, Ag surface doped TiO2-SiO2 composite film exhibited excellent photocatalytic activity. It is believed that the microstructure of the composite film is responsible for improving the photocatalytic activity.

By means of Oxygen and Nitrogen Analyzer, Metallographic Examination, SLIME, SEM, EDS, etc, the cleanliness of ultra-low carbon steel first slab produced by LD-RH-CC, and the comparative analysis with the cleanliness of normal slab is studied. The results show that T[O] and [N] are obviously decreasing with the increasing of casting length. The micro-inclusions and large-inclusions are generally decreasing with the increasing of casting length. The micro-inclusions of the first slab are mainly from deoxidization products and reoxidation of liquid steel. And the sources of large-sized inclusions mainly are reoxidation of liquid steel, slag entrapment in mould or tundish and stuffing sand. The cleanliness of ultra-low carbon steel first slab is closed to those normal slabs at the length of 3.5m.

Many researchers have shown for decades that there is strong correlation between foliar color and its nitrogen nutrition status. However, their results also proved the big difference of this correlation among different crops or plants. In this paper, foliar image color features especially for rubber nitrogen nutrition status analysis are presented by comparative studies on current color feature indexes. Experimental results have shown that the ratio of red or green component to the blue component with detection rate of more than 98% is more suitable for rubber nitrogen nutrition analysis than any other correlations.

The route planning is an important part of UAV mission planning, especially for anti-submarine ship-based UAV. When a ship-based UAV searches submarine, it must be planned a route reasonable. Various restricted conditions are considered in this paper, including the capability, oil cost, air threat, and aviatic area. Under the condition of reasonable assumed tactics, an optimal route, which is from the original point to the target point, is planned for the ship-based UAV, with voronoi diagram, Dijkstra algorithm, and genetic algorithm. The method and the result provide an efficacious guarantee for the ship-based UAV to complete the mission of searching submarine

With the development of embedded system, the implementation of application based on Qt and embedded Linux is an emphasis in researching the embedded GUI system. This paper introduces the cross compiling process and Qt/Embedded, and then describes how to develop the applications on Qt/Embedded. The methods in this paper have been validated on this developing platform(QQ2440V3)．

This paper is mainly about power quality monitoring system analysis method, designs and implements the system based on object-oriented UML platform. Combined with UML modeling language CASE tool rational Rose, and further analysis, finally realize the power quality monitoring system.

The wicking properties of porous polyester, Coolmax and conventional polyester rotor yarns were tested with the capillary flow of a colored liquid and the height was recorded against the time. The relations of material structure, temperature, and yarn count factors to wicking properties were discussed. Results showed that: the moisture conduction of porous structure yarns were best of all yarns; Higher temperature results the faster of wicking speed, and is especially for porous polyester; The finer Coolmax and conventional polyester rotor yarns are of faster wicking speed, but this rule is not distinct for porous structure polyester.

Fatigue failure of gears carrying heavy loads is the leading cause of gearbox breakdown in the large-scale earthmoving machinery. The fatigue life of gear is mainly determined by loads distribution. Taking the Wheel Loader as an example, this paper introduced an indirect test system of gear load under the loose soil conditions. Then the load data in time, amplitude and frequency field were respectively analyzed. The results show that the indirect measurement method proved workable, and the load data of gear is characterized by bi-modal. Therefore, to decrease statistical errors, mixture model must be adopted to fit these bi-modal signals.

A new Rollover Protective Structure (ROPS) of the large-scale wheel loader was designed based on a buffer-induced structure. Dynamic Finite Element analysis model of the entire vehicle was created and boundary conditions of typical rollover cases were given. Optimization design of this new ROPS was obtained through a comprehensive analysis of 16 dynamic simulation samples, which were designed by Orthogonal Experimental Method. Comparison analysis of dynamic response results between original ROPS and optimal new ROPS indicates that this new ROPS effectively prolonged the duration time of the first collision and reduced the acting time of peak force. Deformation extent of main structure of this new ROPS is significantly smaller than that of the original ROPS. Buffer-induced structures can increase the kinetic energy absorption capability of ROPS. Therefore, it can reduce the possibility of brittle fracture of ROPS and improve the probability of operator survival.

Construction of a real estate project is close to one side of the metro station which has finished main structure building. The diagram of the metro station is used as supporting during the excavation of the pit of the real estate project, which will result in the one side unloading of the metro station. Bearing the unbalanced soil pressure, the metro station will have additional deformation and internal force. During the pit design, the additional deformation and internal force is analyzed for every step of the excavation. And the additional force is superimposed with the original force of the metro station to calculate the final internal force of the metro station. By adjusting the design parameters of the pit, the safety of the metro station is evaluated.

The interval tunnel of Ningbo metro line 2 goes through the site of a car showroom project. By FEM analysis, the internal force of the tunnel is calculated under the ground upper load. From the engineering planning of the two projects, the time interval of the two projects is about six months to twelve months. When the interval tunnel begins to construct, the settlement of the foundation of the showroom is still not finished. By the analysis of consolidation rate of soil, the additional settlement of tunnel caused by the latter settlement of the showroom building is analyzed. And the safety of the tunnel is evaluated according to the analysis.

The evolution operator approach is applied to studying photon-electron pumping effects on a quantum dot connected to two magnetic leads in the presence of both via-dot and over-dot tunneling channels. It is found that a microwave field applied to the quantum dot may give rise to charge and spin pumping at zero bias voltage for asymmetric magnetic junctions.

The evolution operator method is applied to studying the time-dependent and spin-related electron transport through a quantum dot coupled to two magnetic-metal leads. When the microwave field is applied on quantum dot there are additional peaks of PAT current besides the main peak of resonant tunneling current, and the energy distance between peaks relate to the frequency of microwave fields. Furthermore, Furthermore, owe to the magnetism of lead, the spin-up and spin-down current is different in the parallel magnetization configuration while the same in the antiparallel magnetization configuration.

The influences of a thin InGaAs layer grown on GaAs(100) substrate before deposited InAs self-assembled quantum dots(SAQDs) were experimentally investigated. Scanning electronic microscope (SEM) measurements show that the InGaAs strained layer may release the strain between wetting layer and QDs, and then enlarge size of QDs. When the thickness of InAs layer is small, the QDs are chained. Temperature dependent photoluminescence (TDPL) measurements show that the PL peaks of InAs QDs with In0.1Ga0.9As show much more red shift compared with the QDs directly deposited on GaAs matrix, and PL integral intensity enhances as T rises from 50K to 90K. We attribute this enhancement to the small potential barrier between WL and QDs produced by the InGaAs stained layer.

The structural durability of wheel loader are required to estimate on the basis of design loading spectrum, which is a spectrum combination of various operating and loading conditions. To generate the load spectrum of transmission system, an actual operational loads of wheel loader under the driving cycle was investigated. A signal collection system was applied to get time-history voltage signals and then torque loads were obtained according to the conversion coefficient between voltage and torque. After zeroing and filtering, the mean, the amplitude and number of load cycles were gained with the rain-flow counting method. The mean and amplitude were tested by Nominal distribution and Weibull distribution respectively. Test results show that they are independent. The two-dimensional joint probability density function of amplitude and mean was gained. After extrapolation, the load spectrum of the spacerflange under whole-life cycle is gained and the process of compiling load spectrum is also provided.

Rh-Ru bimetallic complex is a novel catalyst used to hydrogenate nitrile rubber, which has high activity and high selectivity. Hydrogenated nitrile rubber with a degree of hydrogenation over 99% and gel-free was obtained using this homogeneous catalyst. In this paper, relative molecular weight and mechanical properties of three types of HNBR, including HNBR hydrogenated by Rh-Ru bimetallic catalyst, Therban A3406 and Zetpol 2000L, were analyzed and compared. The results showed that the relative molecular weight of HNBR increased a little after hydrogenation compared to NBR, its mechanical properties were superior to those of Therban A3406 and Zetpol 2000L, and their oil resistant and rheological curves at 130°C and 140°C in the range of shear rate 0∼100s-1 were similar.

The linear random isoprene-styrene copolymer (L-SIR) was prepared by solution polymerization with cyclohexane—n-hexane mixture as solvent and n-BuLi as initiator in the presence of the polar regulator—tetrahydrofuran (THF). Microstructures of L-SIR have been studied by 1H-NMR.

In this paper, low cis-butadiene (LCPB) is used in the process of polymerization of HIPS to study the influence of the polymerization condition on the particle size of rubber and mechanical property. It can be discovered from the study that the particle size was increased from 300nm to 500nm with the decreasing stir. The test of mechanical property shows that with the increase of content of rubber, elongation at break and impact strength on cantilever increase, but stretching strength decreases. On condition of 100 rpm, when the content of rubber increases from 3% to 9%, elongation at break increases from 21.9% to 25.0%, stretching strength decreases from 30.5 MPa to 23.9 MPa, and the cantilever impact strength increases from 5.4KJ/m2 to 9.3KJ/m2. On condition of 200 rpm, when the content of rubber increases from 3% to 9%, elongation at break increases from 21.4% to 29.1%, stretching strength decreases from 28.7 MPa to 20.8 MPa, and the cantilever impact strength increases from 5.2KJ/m2 to 8.1KJ/m2. Keywords: HIPS, mechanical properties, morphologies, T117 initiation