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A Ni60/Ni-WC composite coating was fabricated by the plasma spraying technology and microstructure of the coating was analyzed. Moreover, erosion resistance of the coating under different erosion angles was tested. Results demonstrated that the coating has lamellar structures and contain some pores. WC particles distribute evenly in the coating and bond well with the parent phase. When the erosion angle increase, the weight loss of the erosion-induced coating increases firstly and then decreases, showing plastic-brittle composite erosion characteristics.

The dilution ratio of the Ni coating prepared by the laser cladding under the assistance of the follow-up feeding pulsed current was optimized by combining back propagation (BP) neural network and genetic algorithm. The model was trained according to the results of the 6-factor 3-level orthogonal experiments. A BP genetic neural network forecast model between cladding parameters (laser power, scanning speed, powder feeding rate, pulsed current, pulse frequency and pulse width) and dilution ratio of coating was constructed. On this basis, technological parameters under the target dilution ratio of the coating were optimized by a genetic algorithm. Results demonstrated that the predicted results of the model are very close to the experimental results in term of dilution ratio of the coating, with a relative error no higher than 2.63%. This demonstrates that the model is reliable and effective. The optimal technological parameters are gained when the dilution ratio of the coating is 17.5%, including laser power=1926.3 W, laser scanning speed =·s-1, powder feeding rate= ·min-1, average pulsed current =, pulse frequency=445.6 Hz, pulse width= 108.4 μs.

A finite element model of temperature field for plasma spraying preset MCrAlY coating during laser cladding was constructed using ANSYS parametric design language (APDL) in accordance to characteristics of preset laser cladding. Influencing laws of laser cladding parameters on temperature field were analyzed. Results show that laser power influences temperature field of cladding samples more than laser scanning speed. Experimental results agree well with simulation results, which prove the accuracy and reliability of the constructed calculation model of temperature field. Heating and cooling laws in the laser cladding process could be mastered through this calculation model. Research conclusions provide some references to optimization parameters in preparing high-performance laser cladding coatings.

The effects of the alloying sequence and refining time on the inclusions in Fe–9Cr alloy reinforced with Y2O3 nanoparticles were investigated. The size and number of inclusions in the alloys were determined via optical microscopy, and their morphology and composition were determined via scanning electron microscopy. The Y2O3 mainly acted as a nucleating agent in the Si–Mn+Y2O3+Ti alloying process, promoting the precipitation of other oxides, which was beneficial for the formation of Y–Ti–O particles. In contrast, no Y–Ti inclusions were formed when the Si–Mn+Ti+Y2O3 alloying process was employed. In addition, the inclusions in the alloy tended to stabilize after refinement for 5–10 min. This study offers a general pathway for the manufacture of oxide dispersion strengthened steel via a smelting process.

The degradation of austenitic stainless steels under irradiation environment is a known problem for nuclear reactors, which starts from atoms displacement cascade. Here, molecular dynamics (MD) simulations have been used to investigate the formation of atomic displacement cascade in γ-iron for energies of the primary knock-on atom (PKA) up to 40 keV at 300 K. The number of Frenkel pairs increased sharply until a peak value was reached, which occurred at a time in the range of 0.1-2 ps. After that, a number of defects gradually decreased and became stabilized. Compared with α-iron, there was less defects in the stable stage, and more clustered defects were produced in γ-iron. Within the range of PKA energies, two regimes of power-law energy-dependence of the defect production were observed, which converge on 16.8 keV. The transition energy also marks the onset of the formation of large self-interstitial atom (SIA) clusters and vacancy clusters. Interstitial and vacancy clusters were in the form of Shockley, Frank dislocation loops and Stir-Rod dislocation loops.

Conventional and nanometer aggregate ZrO2-7wt.%Y2O3 ceramic powders taken as raw materials, plasma spraying and plasma spraying-laser remelting compound technology was used to prepare conventional and nanostructured thermal barrier coatings on the TiAl alloy surface. Effects of powder structure (feedstock) and laser remelting on organizational structure and phase of the coatings were analyzed using scanning electron microscope (SEM) and X-ray diffractometer (XRD). Results indicate that: conventional plasma sprayed ceramic coating presents typical lamellar stacking features; plasma sprayed nanostructured coating consists of fully melted region and partially melted region, presenting a two-phase structure. Under the comprehensive impacts of laser power, energy density, temperature field distribution in the laser action region, ceramic heat conductivity coefficient and coating thickness and other factors, the coating presents obvious lamellar structural features after laser remelting; the upper part is compact columnar crystal remelting region and the lower part is residual plasma spraying region. Due to toughening effect of residual nanoparticles in the remelting region of laser remelted nanostructured coating, grain-boundary strength is high and there are a considerable number of transgranular fractures, but the fractures in the remelting region of laser remelted conventional coating are basically intergranular fractures. Conventional plasma sprayed ceramic coating is mainly of tetragonal phase together with a small quantity of monoclinic phases, but nanometer plasma sprayed ceramic coating only has non-equilibrium tetragonal phases. After laser remelting, both conventional coating and nanometer coating mainly have non-equilibrium tetragonal phases with a small quantity of cubic phases.

Plasma spraying technique was used to prepare MCrAlY coating on TiAl alloy surface, the coating was treated through the laser remelting process, and then scanning electron microscope (SEM) and X-ray diffractometer (XRD) were used to analyze surface topography and phase composition before and after hot corrosion behavior of the coating. Results indicate that after laser remelting treatment, lamellar structure of the coating disappears with improved compactness and most defects like pores and inclusion eliminated. Plasma sprayed MCrAlY coating can significantly improve hot corrosion property of TiAl alloy, which can be further improved after laser remelting. MCrAlY coating mainly experiences surface oxidation reaction and internal sulfurization reaction during the hot corrosion in the high-temperature molten salt, which mainly generate corrosion products such as Al2O3, Cr2O3, NiO, NiCr2O4, Ni3S2 and CrS.

In this paper, a low nickel superalloy used for automotive valves was treated at different heat treatments. The metallographic structure and hardness with various heat treatment process were studied. Optimized process guarantees test superalloy can meet the technical requirements.

As the key component of the high temperature gas cooled reactor (HTGR), the performance of the plate fin heat exchanger determines the working efficiency and life of the HTGR. Although the plate-fin structure has lots of advantages such as high efficiency, compact structure, low manufacturing cost, its application will be affected by the vacuum brazing technology and harsh conditions, like high temperature and high pressure. In the practical application of plate-fin heat exchanger, the process of "splitting" between the fin and the diaphragm is very similar to that of the adhesive joint and the delamination of the composite. In the present study, a T-type specimen was designed for the the peel testing of brazed joints. Five kinds of specimens were designed based on the difference between the weld gap and the thickness of the sample base material. The tests were carried out under 450°C and 650°C at five kinds of loading rates, respectively. The peel force-displacement curves of standard samples were obtained . The maximum peel strength and average peel strength were calculated. In addition, the influence of base metal thickness, brazing gap, loading rate and test temperature on the maximum peel strength were analyzed by controlling variable method. Keywords: brazing joint; T-type peel test

The interaction between an moving edge dislocation and helium bubble was studied in BCC-Fe using Molecular dynamics（MD）simulation. Edge dislocation passed the bubble via cut mechanism. A step with a length of b is left on both sides of the bubble after dislocation left away. The influence of simulation temperature, defect size and He/V ratio in bubble on critical resolved shear stress (CRSS) for dislocation to shear bubble were investigated. The CRSS increases with increasing defect sizes, and decreases with increasing temperature. When He/V ratio is at the range of 0-1, CRSS depends weakly on the He/V ratio. The estimated obstacle strength of helium bubble based on MD simulations is acceptable and reasonable agreement with one deduced from the dispersion barrier-hardening model applied to experimental results.

In this paper, we reported on the preparation of porous materials via a reaction under Autogenic Pressure at Elevated Temperature (RAPET) at 700°Cusing natural product and alkoxides as precursors. The RAPET is a new simple efficient method to prepare inorganic materials. The porous carbon and its composite materials were prepared via the method of RAPET using natural products such as sweet potato, coriander, the absorbent cotton and viscose fiber doped by tetrabutyl titanate (TBOT) and tetraethoxysilane (TEOS). The reaction temperature of RAPET was 700°C. The carbon and its composites were studied with scanning electron microscopy (SEM), X-ray diffraction (XRD) and nitrogen adsorption-desorption measurements. The BET surface area of the materials are different from 4m2/g to 405m2/g. The XRD investigation indicates that the phases of the TiO2 in the carbon/TiO2 composites are anatase. The materials show a certain charge-discharge performance.

In order to improve the purity of bearing steel, the VIM+ESR+VAR triple smelting process was used to smelt 9Cr18Mo stainless bearing steel. The content of harmful elements, non-metallic inclusions and microstructure of the steel were studied. The results show that, the content of harmful elements of the steel is very low. A fairly small number of non-metallic inclusions are uniformly distributed and fine. The purity of the steel reaches a higher level. After thermal processing and heat treatment, the microstructure of the steel is the same as 9Cr18Mo bearing steel smelted by normal process, but the primary carbides in the steel is more uniform distribution and finer.

GTD222 superalloy is a potential candidate for large-scale complex thin-walled castings with high temperature resistance in the next-generation aircraft engines, due to its excellent creep performance, good oxidation resistance and favorable weldability. The precision casting of GTD222 with a complex thin-wall structure was investigated in this work. The good quality of the final cast indicated that the optimized gating system obtained by numerical simulation was satisfying.

A novel method to remove impurity silicon from aluminum melt by the addition of K2TiF6 was studied. The mechanism for silicon removal is the formation and sedimentation of Ti(Al1-x,Six)3 phase and the removal efficiency is mostly decided by the solubility of silicon in TiAl3 phase, which increases with the increasing of the initial silicon concentration in aluminum melt. The effect of holding temperature on the impurity Si purification efficiency was investigated and the result indicated that the effect of holding temperature is very finite.

The aim of this work is to investigate the effect of different casting speed in DC casting process and solution heat treatment of in situ Al-13.9%Mg2Si composite. The increasing of DC casting speed not only makes primary Mg2Si distribute more uniform and restricts segregation of primary Mg2Si particles, but also it reduces primary Mg2Si particle size. The DC casting speed significantly alter the eutectic Mg2Si phase from fibrous to fine dot-like and eutectic phase refines effectively. The results obtained from mechanical testing demonstrated that the increasing of DC casting speed intensifies both hardness and tensile strength values. Then, the billet were subjected to solutionizing at 500oC for holding time of 4h followed by quenching. The results indicate that the morphology of both primary and eutectic Mg2Si changes after heat treatment. Solutionizing leads to the dissolution of the Mg2Si particles and changes morphology from sharp edges to round shape. After solution heat treatment, tensile strength and elongation increase to 238.8MPa and 13.5%.

The effect of phosphorus on primary silicon, phosphorus and mischmetal (Ce-50La) modification on primary and eutectic silicon and cooling rate on microstructure of Al-25%Si are investigated. The results show that, with the addition of phosphorus, the size of primary silicon decreases from 93.6μm to 24.75μm. The morphology of primary silicon changes from irregular to polygonal. When Al-25%Si is modified by phosphorus and mischmetal, primary and eutectic silicon all change effectively. Addition of mischmetal on the basis of phosphorus modification have no influence to primary silicon, but it can make morphology of eutectic silicon change from lamellar to short rod-like when the content of mischmetal reaches 0.5%. The cooling rate curves show the change of temperature in different height of wedge-shaped mould. When cooling rate increases, microstructure of Al-25%Si refines, the size of primary silicon decrease to 22.7μm. The results obtained from mechanical testing demonstrate that the addition of mischmetal and increasing of cooling rate increase hardness value of Al-25%Si alloy.

An experimental research on the reduction of vibration of ball bearings is provided in this paper. The waviness of inner race and outer race are decreased by superfinishing process, and their excitation frequencies are obtained. After the bearings’ vibration is tested, the powers of vibration distributed in different frequency regions are computed. The results reveal that the waviness excitations have a considerable influence on vibration of ball bearings in medium-frequency ranges, and the vibration can be reduced greatly by superfinishing process.

The effects of different solid-solution temperature and holding time on the alloy structure and mechanical properties of alloy 718 were investigated. The results show that the grain size grows up as the solid-solution temperature elevates and the holding time prolongs. The grain size increases slowly because undissolved delta phase restrains the growth of grains when solid-solution temperature is below 1000°C, whereas the grain size increases quickly when solid-solution temperature is beyond 1050°C. At room temperature, the strength and hardness of alloy 718 decrease with solution treatment temperature increasing, however, the ductility and toughness of alloy 718 both increase, and the brittle fracture of sample turns into ductile fracture.

To resolve the materials corrosion problems during exploiting high H2S/CO2 oil and gas field, the corrosion behavior of 718 nickel base alloy for 720 hours was studied, the conditions of the experiment is about temperature=177°C, P(H2S)=3.0MPa, P(CO2)=13.5MPa, solution mixed NaCl 20%wt.. The Electronic Parts Manufacturers Association (EPMA) and electrochemical methods was applied to characterize the microstructure, chemical composition and impedance characteristics of corrosion film. The results show that the surface of corrosion film is mainly composition by sulphide of Ni, Cr and Fe, the inside of corrosion film is mainly composition by oxide of Ni, Cr and Fe, electrochemical analysis found the alloy could resist corrosion in this environment.

With the application upgrade of alloy 718 in the marine oil exploitation, higher corrosion resistance demands has been presented for structure design and reasonable material application of drilling and production equipments; thus there is an urgent need to understand influences of grain size on corrosion behavior of such alloy in sea water environment. In this experiment, different solution treatments are applied to nickel-based alloy 718. As a result, specimens with grain size varied from ASTM No. 9 to No. 3.5 grades. The influences of grain size on the electrochemical behaviors in simulated sea water (3.5% sodium chloride solution) are investigated using electrochemical impedance spectroscopy and polarization curves. Alloy 718 shows good corrosion resistance in this electrolyte solution, however, grain size still has an effect on its electrochemical corrosion behaviors to a certain extent. With the time going, testing results show that coarse-grained alloys with larger grain size have higher impedance values and smaller corrosion current densities, indicating a better corrosion resistance than fine-grained specimens. However, when the grain size increases further, the corrosivity resistant nature of alloy 718 would decline. Testing results show that specimen with size of ASTM No. 5 has the best corrosion resistance.

The factors that influence environmentally-friendly powder rubber powdering are introduced. Types and dosage of isolation agent, types and dosage of coagulant, environmental antioxidant, condensation temperature, stirring speed on the effect of powder rubber are examined. Thus a simple method to prepare environmental powder rubber is provided.As a physical variation of traditional bulk rubber, powder rubber can change the situations that high energy consumption and high labor intensity of the former. And it also can make the mixing process become continuous, automated, energy-saving and so on. In recent years, with the progress of rubber processing industry, the demand of powder rubber increases rapidly. And there is a intense requirement of supplying environmentally-friendly powder rubber[1-3]. So it is very important to do this experiment.

The TiO2complex samples were produced through sol-gel method, using Ti (OC4H9)4, rice husk (RH) and methenamine as the reactants. Some property analyses were conducted, including X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and photocatalytic experiments in the condition of visible-light. The results showed that the size of crystal was limited with the addition of RH in the complex of N/RH/TiO2samples. The particles of TiO2were dispersed on the surface of rice husk ash, the skeleton of RH after burning. It can inhibit the phenomenon of agglomerate. The ability of both adsorption and photocatalytie activity of complex samples increased as the surface area increased. Doping N into RH/TiO2samples can decrease the forming time, inhibit the transformation of crystal from anatase to rutile to some extent, improve the bond of Ti-O-Si to form and make the absorption spectrum move to the red light part. The complex samples exhibited a certain photocatalytic activity under the visible light region. The reaction rate of visible light photodegradation process arrived 0.0143 min-1, meeting with the first-order reaction kinetics.

According to the finite difference method and thermal elastic-plastic theory, combining with martensitic phase transformation kinetics and considering the latent heat and microstructure stress, the temperature, microstructure, stress and strain fields are analyzed. The research indicates that at the beginning of cooling, there are great temperature differences in the direction of thickness and width; at the end of cooling, the temperature and microstructure fields become homogeneous, but the stress and strain field is seriously inhomogeneous. A larger plastic strain occurs on the surface and distributes inhomogeneously in the direction of width are the basic reasons of residual stress. A theoretical basis is provided for improving the offline heat treatment process by analyzing the reason of bad flatness.

Based on the emus' VIP test of floor shock absorber, the parameter optimizations are conducted. Through the experimental comparison and analysis of low stiffness with high damping, stiffness damping and the original car shock absorber, it proved that the high stiffness damping vibration damping performance is better than another two kinds of shock absorber.

In this paper, a runoff forecast model combining similar process derivation with probabilistic forecasts is proposed. Certain forecast result is computed by similar processes derivations, and on the basis of certain results, a confidence interval under given confidence coefficient is worked out by probabilistic forecast part. The model is simple in structure, easy in establishing and unnecessary to concern for predictor selections. Applying above model in simulation experiments, the results show the forecast model have excellent forecast accuracy and can be used in monthly runoff forecast effectively.

In this paper, based on the honeycomb floor damper of high-speed train, the finite element analysis was carried out on the floor damper, and we compared the experimental results with the physical model experiments. The results show that: when correction factor γ = 0.5, there is the minimum incremental error of vertical deformation, and the value of the damper parameters is the best at this time.

A numerical model including thermal and microstructural model is established for precisely prediction of residual stress of hot-rolled strip on run-out table. Temperature and phase transformation fraction are coupled and formulated for the calculation of thermal and transformation expansion that could induce internal stress. Residual stress for hot-rolled strip before and after coiling are calculated using C++ program. Influence of edge masking on residual stress is analyzed. It is concluded that edge masking makes the strip flatness better after coiling.

With the wind power developing fast in the world, the large scale of wind power integration in power system leads to great challenges, and the wind power forecasting will play a key role in dealing with these challenges. A wind power short-term forecasting method based on grey system is introduced in this paper. Firstly, a basic model of grey prediction method is given. Then, in order to smoothen the basic data for the grey modeling, a self adaptive grey prediction method is developed. Finally, the result of prediction for a test system of wind power are presented and the effectiveness of the method given by the paper has been proved.

Photovoltaic (PV) power generation is one of important direction of future energy development by most countries. The research on power flow calculation of power system with grid-connected photovoltaic generation based on Matpower is given in this paper. Firstly, a stochastic model of PV system is presented in the paper. Then, Matpower is used in the simulation of power flow for IEEE 57 node system. Simulation results of with PV generation and without PV generation in IEEE 57 node system are presented. Comparison between the results shows that adding PV generation in power system will have great influence on power flow of power system.

At the present stage of excavation design,the embedded depth of braced structure should meet the requirement of circular sliding stability when the bottom is soft soil. By increasing the embedded depth of support structure, the requirements of stability could be meet. In the normal design, the support structure must penetrate the soft soil layer when the bottom exist soft soil. While when the excavation is narrow and long, because of the obviously spatial effect, there is no need to determine the embedded depth based on the general circular sliding stability. In this paper, based on one the project example, calculate and analyze the similar stability using strength reduction method through the finite element software Plaxis and Midas.

The tensile strength, elognation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of Cu-Ag alloy with 80% deformation is 405°C×5h.

Concept lattice in essence describe the links between objects and attributes,demonstratesthe generalization and specialization of concepts. The corresponding Hasse diagrams realize the visualization of the data. At present, formal concept analysis has been extensively studied and applied to many areas, such asinformation retrieval, machine learning andsoftware engineering. Based on the above reasons, it is necessary to research the methods of latticeconcept of data mining. This paper is divided into three parts; the first part introduces the basic concepts of data mining. The second part introduces the basic theory of concept lattices. The last part focuses on the application of concept in data mining.

The tensile strength, elongation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of HSn88-1 alloy with 80% deformation is 460°C×5h.

The mechanism of cable crosstalk involving what and how does the factors affect the level of crosstalk is introduced in detail. A transmission line model for predicting crosstalk between power cable and the other wires nearby with common reference ground based on multiconductor transmission theory (MTL) is developed. Crosstalk among circuit configurations when the victim cables with load terminations are different types is analyzed and simulated. Models where the types of the victim lines are shielded coaxial cable, shielded twisted pair and unshielded twisted pair are simulated. It is found that the shielding can provide an attenuation of about 50dB than the unshielded cables. In addition, the condition of multi-cable coupling is simulated and some thoughts are brought out to inspire more detailed study. Finally, some measures are suggested to suppress the crosstalk between cables according to the two-type of coupling mechanism (inductive coupling and capacitive coupling).

To improve the accuracy of load forecasting and cope with the challenge of single computer’s insufficient computing resource, a short-term distributed load forecasting model based on LSSVM optimized by IPPSO is proposed. Uncertain parameters are optimized by improved parallel particle swarm algorithm which runs on the Spark on Yarn memory computing platform. The real load data provided by EUNITE is used, and experiments and analysis are conducted on an 8-node cloud computing platform. The results show that the accuracy of the algorithm proposed by our paper is better than the traditional functional networks algorithm, the efficiency of the algorithm is better than MR-OSELM-WA, and the algorithm has good ability of parallelization.

Thispaper studies the method of detecting antibiotic trimethoprim (TMP) in theenvironment water, sewage and tap water with high performance liquidchromatography –diode array detector (HPLC-DAD). The chromatographic conditionis confirmed that: the stationary phase is ODS, the mobile phase is acetonitrileand methanoic acid aqueous solution of 0.1%（12:88）, the flow rate is 1.5min·L-1; theinjection volume is 5μL，the chromatographic column temperature is 25°C,DAD detection wavelength is 272nm. The experiment result shows that, the linearlydependent coefficient of external standard curve is 0.996, the detection limitis 0.017 mg·L-1, adding standard recovery ranges from 92.6-140.6 ％.

As a new numerical simulation method, the extended finite element method can deal with the discontinuous problems more effectively than the finite element method. In this paper, the basic theory about the extended finite element method is introduced briefly. The stress intensity factor of the crack of mode I is numerically calculated based on the extended finite element method. The numerical calculations show that the extended finite element method is an approach with high-efficiency for the problems with crack.

The reliable detection of composite material is dramatically important with its wide application in the aerospace industry. A new post-processing mode of ultrasonic array inspection, entitled total focusing method(TFM), offers significant advantages including high sensitivity and greater inspection coverage. Based on this mode, a wave velocity correction method for the elastic anisotropic of composites is put forward. Subsequently, practical application is carried out to image and locate the defect in a composite laminate sample to demonstrate the advantage of the described method. The results show that the proposed method can effectively improve the ability to detect and evaluate defects in composite laminates.

There is a unique inflorescence composition and stamen structure in Compositae. Stamen structure, filament movement and its mechanism was analyzed and discussed, with cosmos and small sunflowers as experimental materials, by using morphological anatomy, microscopic measurement, tabletting observation. The results showed that: (1) There was a certain regularity in the opening of tubular floral organ in capitulum, of which their movements were initiated from outside to inside. (2) The mainly cause of stamen movement in Compositae came from the changes filaments length. (3) Stamen movement was not a simple physical movement-with filaments shortening, cell structure also has changed. (4) The filament movement in Compositae is not only beneficial to itself fully stretching, but also reduces the interference during pollen spreading.

In this paper, a fuel cell power system is considered to supply DC power for a Peltier based cooling process. For the fuel cell, there exist slow dynamic response and soft characteristic due to long-running. Therefore, the fuel cell hybrid power system is designed, including fuel cell, battery, unidirectional DC-DC converter and bidirectional DC-DC converter. In order to reduce the slow dynamic response and soft characteristic, it is the most important that the bidirectional DC-DC converter is controlled for charging or discharging to the battery. A control scheme combined feedforward and feedback is proposed for the bidirectional DC-DC converter, where feedforward control is based on the output voltage of the fuel cell. Simulation results based on the designed circuit and proposed method are given to verify the performance of the converter.

This article selects HOL theorem proving systems for hardware Trojan detection and gives the symbol and meaning of theorem proving systems, and then introduces the symbol table, item and the meaning of HOL theorem proving systems. In order to solve the theorem proving the application of the system in hardware Trojan detection requirements, this article analyses basic hardware Trojan detection methods which applies for theorem proving systems and introduces the implementation methods and process of theorem proving about hardware Trojan detection.

The paper realized a smart home system based on FS_S5PC100 hardware platform and Android frame, and finished the JNI procedures, the Linux bottom drivers and the user interface based on Java. It provides the good theoretic references for develop the real relevant smart home systems in the future.

To investigate the brain default mode network (DMN) of healthy young people, a novel hierarchical clustering method was proposed to detect similarities of low-frequency fluctuations between any two out of 160 regions of interest (ROI) all over the brain. Feature of these ROIs were firstextractedand analyzed the feature using hierarchical clustering approach.Combining with the strongest connected network node identified by network centric criterion, the default mode network which presented the strongest connectivity in resting state was then determined. The results demonstrated that cingulate had the highest value of average degree, making it the most suspectof where the centrality indices of DMN lay.The comparative results between nodes included by DMN returned by our method and these given by Dosenbach’s research showed quite high coincidence rates,indicating the proposed method of combining complex network theory and hierarchical clustering analysis feasible method to parse brain regions.

By using the single-chip microcomputer AT89C52 and the DS18B20 temperature sensor, this paper designed and realized an oil pump temperature monitoring system based on Internet of things. By installing the DS18b20 sensors in front of and behind the oil pump motor bearings; this monitoring system can collect the real-time temperature data of the oil pump bearing. The changed temperature data can be uploaded to the computer or the hand-held terminals by the transmission module when the temperature of the pump bearing changes. Especially, when the temperature is more than the alarm value preset by the system, the system can automatically send alarm signal, such as ring tones and screen flashing, and start the alarm module to warn the staffs to do the relevant work timely.

In order to automatically set the shape target curve, a model based on shape control theory is put forward. By coupling the shape forecast model and the shape discrimination model, the practical and strict shape target curve is researched. By combining strip plastic deformation model and rolls elastic deformation model, the shape forecast model is built. The shape discrimination is based on the strip element method. The main idea of the shape target curve is to minimize the shape crown in the first few passes on the condition that the strip is not unstable, in the last two passes to keep the good shape under the natural shape crown. Taking five-pass six-high rolling mill as an example, the convex strip is analyzed. The simulation and calculation results prove the validity and feasible of the shape target curve setting model. This model develops the shape target theory and lays the foundation of application of shape target curve in the rolling process of cold rolling.

According to the characteristics of the wind farm measuration and the impact of bad data on the state estimation, this paper introduces the reference value of measurement type and the bad data reference factor into the weight function, and then presents the calculation method of state estimation method for solving residual contamination problem caused by large-scale wind power integration. In order to improve the software computing speed and the data section real-time performance of robust state estimation, using parallel algorithms to do Givens transformation. Finally, the simulation tests of a regional power grid to prove that the proposed method can effectively identify telemetry bad data of wind farms eliminate residual pollution caused by it, which improve the speed and accuracy of the State Estimation.

By examining the compressive and flexural strength of composite and using scanning electron microscopy (SEM), we analyzed the influence of sodium hydroxide on the properties of FGD gypsum and slag composite materials and discussed the influence of sodium hydroxide on the setting time and mechanical strength of the composite materials and presented the action mechanism of sodium hydroxide as a stimulator. The results show that when the content of sodium hydroxide was percent of 0.25, the maximal strength of FGD gypsum-slag composite materials was reached.

A variety of different magnetic structure models of cobalt doped zinc oxide have been calculated by density functional theory (DFT) of first-principle method. Crystal structure parameters and the total energy of the models are obtained through the computational simulation. Through contrasting and analyzing the total energy of each of the structure models, it is found that the cobalt doped zinc oxide crystal material with anti-ferromagnetic state is more stable than the one with ferromagnetic state. The electronic structure of the models with anti-ferromagnetic is investigated and the results show that the cobalt 3d electrons have a great impact on the characteristics of the electronic structure of the zinc oxide.

When larger scale of small hydropower and wind power exist in power system, the traditional reserve capacity algorithm is no longer applicable at the same time of reducing the carbon emission. Aiming at the volatility and non-regulatory of small hydropower and wind power, considering the forecast error of small hydropower, wind power and load,the unit outage rate and other factors, combined with the actual operation parameters of one regional power system in Southwest of China, the wind-hydro – thermal power coordinated operation of multiple objective function optimization calculation model of reserve capacity is established. Using the weighted coefficient method of unified objective method, it transforms the multi-objective optimization problem into a single objective optimization one. Applying the exterior penalty function method, the constrained optimization problem is changed into a non-constrained optimization one. The improved particle swarm optimization algorithm is got by introducing the particle concentration cognition into traditional particle swarm optimization algorithm. The simulation results verify the validity of the model. To Compare them under different strategies, this method can get less fuel expenses of thermal power units in the case of lower loss of load probability (LOLP).With the small hydropower and wind power output size to optimize the spinning reserve capacity. The model and the algorithm are helpful for drawing up optimization strategies of the reserve capacity in those regions in which larger scale small hydropower and wind power exists.

In order to obtain the low synchronous speed, fractional-slot concentrated-winding PM machine is adopted to wind power generation system. This paper analyzed the pole slot combination rule, and then studied the electromagnetic design method by taking 12-slot and 10-pole machine. By using the finite element software, the characteristics is analyzed for this fractional-slot concentrated-winding permanent magnet generator, the research results show that this generator has good performance, thus prove that fractional-slot concentrated-winding scheme is feasible and effective.