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To solve the problems of high dimension, multicollinearity, easily over-fitting, this paper further studies characteristic wavelength selection method, and proposes the improved successive projections algorithm based on mean impact value algorithm (SPA-MIV). The results show that the proposed algorithm reduces data dimensions and improves data quality effectively. After being processed by improved successive projections algorithm, the determination coefficient of of testing set of moisture, ash and volatile PLS calibration models are increased to 0.9318, 0.9127, 0.9389, and the of testing set determination coefficient of moisture, ash and volatile BP neural network calibration models are 0.9645,0.9432,0.9536.

The paper proposed a Wireless Sensor Network (WSN)’s Sybil node discovery method based on groups relative location information. By setting the distributed algorithm of node group, the relative locations of each node with its surrounding and interactive nodes are analyzed location, interactions of surrounding location information are done by a certain mechanism. According to group location information and data filed, the clustering analysis of location information is carried out. This is used to discover the nodes which are obviously closer than others location. Therefore recognition and tolerance of Sybil nodes are implemented. The simulation results indicate that the proposed method has much lower computational cost and implements load balancing among different nodes,. In addition, the proposed method is able to discover Sybil nodes in wireless sensor networks timely as well.

The gating system of an injection mold for car bumper was studied. A design optimization scheme is proposed to optimize both the number and locations of the gates by analyzing the filling process, in order to reduce the part war page and weld line, numerical simulation of injection mold filling process is combined with the design optimization method to find the optimum number of gates and their locations to achieve balanced f low and less weld lines while satisfying the limit of injection pressure. Moldflow software was applied to make analysis and comparison of various gating system in terms of their filling time, injection pressure and clamp force, weld line and distribution of air traps, and an optimized gating system was obtained. The result shows that this method can effectively reduce costs, shorten development cycle and improve the efficiency of molding design.

Dynamic compaction is one of the densification techniques of ground improvement and extensive theoretical, experimental and in-situ tests have been used to clarify its mechanism. In this paper, a literature review about the dynamic compaction is carried out and the emphasis is put on the reinforcement mechanism, effective reinforcement depth and influence range of vibration to give a reference for the ongoing researches of dynamic compaction method.

In order to build an accurate spray model for studying the characteristics of n-butanol and diesel blends. First, the calculation of gas-liquid two phase flow inside the nozzle was carried on, the birth and development of cavitation and the non-uniformity of the velocity field inside the nozzle were analysed. Then the spray model coupled flow inside the nozzle was established and verified. The spray simulation calculation of n-butanol and diesel blends was carried on by using the model, and compared the results with the results of flow inside the nozzle not coupled. The results show that the droplet speed, spray penetration and SMD of D100 and N40 is all bigger under the condition of without coupling flow inside the nozzle. The flow inside nozzle will affect the whole spray process and spray characteristics, which will ultimately affect the combustion and emission characteristics. So the spray model coupled flow inside the nozzle can provide accurate initial condition for spray calculation, which can reflects the fuel spray characteristics truly.

Affected by the climate change and human activities, the consistency of Measured Runoff Series (MRS) is changing. The methods of reduction modification and current modification are commonly used to the inconsistent MRS in domestic, the modified runoff series will be used to water resources assessment as the basic data, but the methods that used to estimate the consistency of Reduction Runoff Series (RRS) and Current Runoff Series (CRS) is subjective to some extent. With the MRS/RRS/CRS from 1956 to 2000 of Huayuankou Station at Yellow River, the influence degree of human activities and climate change to the inconsistency of runoff series were analyzed preliminarily, then the hydrological alteration diagnosis system was used to estimate the consistency of runoff series, with the parameters of Hurst coefficient and the alteration classification, the modification effect of RRS/CRS was analyzed. The results show that, although the consistency of RRS/CRS was improved, the alteration still existed, they should be modified further more to satisfied the requirement of water resources assessment, or the assessment method that adjust to the inconsistent runoff series should be adopted.

Hollow cylinder torsional shear test is simulated regarded as a boundary value problem employing a three-dimensional static/dynamic soil-water coupled finite deformation analysis to investigate the influence of the specimen geometries on apparent behavior concerned in practical experiments. 1) A “Perfect path” which means the response of a single three-dimensional element with uniform deformation is calculated to investigate the effect of non-uniformities on the apparent behavior. As can be seen, only the apparent behavior with thinnest wall thickness coincides with the “Perfect path”, which indicates a uniform deformation inside the thinnest specimen; 2) It was found that when the cylinder wall thickness became smaller, the non-uniformity also decreased correspondingly, which can also be seen in the element behaviors of the thickest specimen; 3) Even thought the non-uniformity in different geometries is quite different, there seem to be no significant influence on the apparent behavior. The reason may lie in the extreme constraint conditions, namely displacement control.

The polyphenylene sulfide (PPS) Nonwoven was modified by grafting polymerization of the acrylic acid (AA) with the initiation of the low temperature plasma. Effects of different treatment conditions on the graft reaction and the hydrophility of the modified PPSs were investigated. Scanning electron microscopy (SEM) images showed that the graft polymerization only occurred on the surface of PPS. The hydrophility of the PPS nonwoven were examined by alkali absorption rate. The results show that the optimum modified conditions are 90s treating time, 50W plasma power and 1.5cm distance between of the electrodes.

A dynamic analysis code has been expanded from the previous quasi-static code and the effect of inertia term is added. In this paper, the influence of inertia term on the pore water pressure is investigated in detail under a uniform deformation field theoretically and it is found that the distribution of pore water pressure is parabolic if there is inertia term. Then in order to verify the calculation precision of this code, the soil-water coupled numerical calculation is carried out based on the assumption of uniform deformation. Special distributively pore water pressure is applied to each finite element according to its radius to keep the uniformity of deformation. The results show that the maximum of pore water pressure appears at the center of circle and it gradually decreases along the radius, which proves the precision of the dynamic analysis code is very high.

In HongKong-Zhuhai-Macao bridge project, about 4.8 kilometers stone bed underwater should be compacted to make it smooth and remove the excess settlement. Vibrating compaction method would be used to tamp the stone layer with no dead angle in a short construction period. This paper theoretical studied on vibrating compaction technology of scattering-filling rubble stone layer. Vibrating compaction system and stone layer were simplified to a mechanical model and the vibration equation was established. According to an interpolation table, a fitting formula of equivalent damping was given. Through rigorous mathematical derivation, this paper gave mathematical expressions of the vibration displacement, the vibration velocity and compaction work on stone layer. Both compaction work on land and compaction work underwater could be calculated by these mathematical expressions. Lastly, through a set of field test parameters, comparative analysis between compaction work on land and compaction work underwater was carried out. The result shows that the weakening effect of water on compaction work is poor.

The SYS Cam-clay model, which is extended based on the Cam-clay model and the critical state theory, is able to describe the heavily overconsolidated and structure soils. However compared with Cam-clay model with five elasto-plastic parameters there are six additional evolutional parameters in SYS Cam-clay model and the sensitivity analysis of the new added parameters should be carried out. Through the calculation of constitutive response assuming the uniform deformation field, the sensitivities of degradation index of structure, degradation index of overconsolidation ratio and rotational hardening index are investigated respectively. It can be seen that the peak strength and the “rewinding behavior” in the effective stress path are influenced greatly while there is no coupling effect of these parameters mutually. The initial overconsolidation ratio and degree of structure also have an effect on the mechanical behavior and the initial specific volume.

Through an underwater camera at the WES Weir of the Dayuandu Project, the heavy sedimentation on the Weir’s floor can be observed. The sediment changes the water flow patterns before the Weir, resulting in Weir surface wear and sluice leakage. Mathematical models and physical had been builded to analyze the effect of the erosion. The results of these observations provide a reasonable and effective scheduling method to solve the siltation problems in front ofthe WES Weir. Once there are sufficient flow intensity, the ternary complex flow patterns will contribute to the incipient motions of sediment, acquireing desirable effect of sedimentation Control.

For the study on the problem of rational width of entry protection coal-pillar, according to the gateway of 5103 mining face in Heshan Mine, through theoretical calculation and numerical simulation, rational width of entry protection coal-pillar was educed, which was 25 m. The roof and floor and 2-sides deformation were both 35 mm through engineering practice, and its feasibility was demonstrated, which provided some theoretical references for preserving reasonable coal-pillar for the similar coalface with large mining height.

In this paper, soil-water coupled dynamic analyses are carried out to investigate the influence of stratigraphic composition on the propagation properties of the seismic waves. SYS Cam-clay model is used as the constitutive model which can describe the different state of clayey and sandy soils. Two cases are considered for the composition of ground: one is the sandy ground with diluvial sand, alluvial sand and reclaimed sand; the other one is the clayey layer at the ground surface. It is found that for the sandy ground even though there is certain amplification of the input acceleration wave during the dense sand layer the subsequent seismic waves through the loose sand layers are attenuated significantly due to the occurrence of the liquefaction. While for the clayey ground, even though there is no risk of liquefaction damages at the ground surface the acceleration amplitude is greatly amplified and there is a risk that the structure itself would fail in the strength.

Based on chemical vapor deposition (CVD) reaction and numerical analysis of the transmission process, analysis the influence law of the process parameters has been conducted for silicon carbide thin film. A detailed analysis on impact of the chamber pressure, substrate temperature and inlet flow has been realized through the use of CFD and chemical reactions software, coupling fluid flow, chemical reactions and mass transfer process in the deposition of SiC thin film. The result of simulation fully proved that the process parameters have different influence law, especially the chamber pressure.

Cryogenic treatment as an effective non-destructive modification of material, has been widely applied. Equipments and technologies of cryogenic treatment were described, the current research status of cryogenic treatment technology on cemented carbide was reviewed, the action mechanism of cemented carbide cryogenic treatment was analyzed. Finally, in this paper some views and outlooks of cryogenic treatment technology in industrial applications were put forward.

Utilizing power line to transmit information speedily and safely is very important and significant. Whereas, the communication environment and construction of power grid are complex and hostile. The paper introduces the application, common modulation technology—OFDM and noise characteristics of PLC. The paper builds an OFDM input and output system and adds the power line noise into the channel, then compares and analyzes the difference between the OFDM output signals in common channel and PLC channel.

By means of raw performance analysis of silt sintered porous brick, the importance of synchronous cutting machine in the molding process was revealed. On basis of the analysis of the present situation of research and application of synchronous cutting machine at home and abroad, according to the forming characteristics of silt sintered porous brick, technical parameters of synchronous cutting machine was explained and the development trend of the synchronous cutting machine was expected.

we studied the spray characteristics of n-butanol/diesel fuel blends using a high-speed camera and schlieren system, and analyzed the effect of different fuels, ambient pressure and injection pressure conditions on the spray penetration, spray cone angle, spray area, et al. The results showed that, at the same injection pressure, as the increase of ambient pressure, the spray cone angle of the same volume of fuel increases gradually, the spray penetration and the spray area decreases; under the same ambient pressure, the spray penetration, spray cone angle and spray area increase gradually with the increasing injection pressure, but when the injection pressure increases enough, the parameters are roughly the same; and the parameters basically all increase with the adding of n-butanol.

The governing equations and the finite element model for the coupled thermo-mechanical multi-pass vertical-horizontal rolling process of a zircaloy strip are established. Considering the temperature-dependent and strain rate-dependent constitutive relation of zircaloy, the numerical simulation of the three-pass V-H rolling process is realized by the coupled thermo-mechanical dynamic explicit finite element method. The computational results such as the plastic deformation, the size variations and the temperature variations in three passes are discussed. The research results indicate that edging by vertical roller benefits improving the sizes of the strip and the temperature variations are rather obvious during the three-pass hot rolling process. The research provides experience and foundations for the FEM simulation of the hot rolling process of composite slabs for nuclear fuel elements.

Parking exposed to the sun brings about a pretty high temperature in the vehicle which irritates most people. In-vehicle temperature regulating system is designed to eliminate this inconvenience. It is composed of the Insulation Section and the Solar Power Cooling Section. The first part utilize the insulation materials to keep the moderate temperature of the instant when the owner leaves the vehicle. The second part uses the solar panels to generate electricity and then powers the semiconductor cooler to work. Thus the air in the vehicle can be kept at a lower and comfortable temperature. This paper theoretically calculates the temperature in the vehicle with and without the system respectively. The curve of temperature variation is described and contrasted with the measured results. A conclusion that this system can inhibit the temperature rise effectively is drawn.

The uC_OS-II embedded real-time operation system is used to improve the original designed fuel supply system of a Stirling engine which governed by the electronic control system based on a rotating speed control method. Task modules for each level are built and the fail-safe modules are also improved in this paper. The developed fuel supply system is investigated through experiment, and test results show that the new real-time operating system works stably and realizes the fuel supply fast adjustment.

In order to overcome the problem that the maintenance date for NC machine parts was lacking, this paper proposed a maintainability prediction method based on comparing with basic unit. The biggest difference from traditional methods was that the traditional methods analyzed parts, but in this method, failure modes were analyzed and interval number was used to express expert opinions. The maintenance action for each failure mode was decomposed into several basic maintenance tasks. Comparatively speaking, the method had more adequate data and higher accuracy. Finally, the method was illustrated with an example. The analysis results showed that the method was feasible for the maintainability prediction of NC machine tools. It could solve the existing principal problems and provide a new idea for predicting maintenance in the field of NC machine tools.

Ship unloader crane was widely used in transportation, and uploaded or unloaded cargoes from ships, which could influence efficiency and benefits of transportation greatly. In order to improve the reliability and safety, and decrease its risk in working flow, a method of fatigue life assessment was proposed in this paper. According to related standards and properties of risk, finite element method and experimental stress analysis were integrated to assess the working condition of a ship unloader crane. Finite element models of primary structures subjected to loads were built to achieve dynamic properties, which could supply a basic reference to experiment and guidance to locate the tested positions. Afterwards, wireless dynamic resistance strain-gauges were adopted to execute static and dynamic stress, and the tested results combined with finite element analysis were applied to strength analysis. Based on nominal stress and Miner principle, rainflow method was developed to fatigue life assessment of this ship unloader crane. The final results indicated that residual life of this crane was 4.67 years.

The paper work had improved some inference information report show functions of the expert system shell Pro/3 by using graph in combination with text . By analyzing some forward reasoning application mechanisms of the Pro/3, this work had also created a transformer fault diagnosis knowledge base rule model based on dissolved gas analysis in transformers such that using the rules of sentence in model had implemented an expert system of transformer fault diagnosis. The basic application shows the effectiveness of the system.The modeling approach created by the Pro/3 can be also applied to some diagnosis or analysis of other equipments. Exploring the Pro/3 has certain practical significance for establishing some expert systems or assistance decision support systems.

Clustering analysis is widely used in data mining, e-commerce, graphic processing, bioinformation and text classification. Multicore computing based on CUDA and GPU is one of the new techniques of data processing, which became an active research direction of parallel computing in recent years. After the analysis and serial k-means algorithms, we propose a new compact parallel k-means algorithm which fit for GPU computing and present three main optimization method.The experiment results show that the algorithm is simple, fast and scalable for real-world data processing with comparison of existing other research.

The high strength and high performance concrete C80~C100 is popularly used nowadays, especially in the West-Tower Project of Gungzhou. In order to provide reference for the use of high strength concrete and the development of ultrahigh pumping technology, the following six aspects were studied, namely the preparation of high strength concrete, the variation of the concrete mixture under high pressure, the index of the ultrahigh pumping concrete, the change after the pumping, the loss of the pumping pressure and the measurement of the pumping viscous resistance.

External wall has great impact on building energy conservation. Developing composite wall is direct way to improve the situation of building consumption. In this study, the importance of building energy conservation was analyzed. Several types of composite thermal insulation wall were listed and their advantages and disadvantages were discussed. Self-insulation composite wall has unique superiority, especially in hot summer and cold winter zone. Meanwhile, the application prospect of composite wall with combinations of insulation coating of high reflectivity and silt sintered porous brick was introduced. Finally, combining regional character, some suggestions were proposed on the further development of China’s composite wall in hot summer and cold winter zone.

Silt sintered insulating brick with high strength, good thermal insulation and sound insulation characteristics. It occupies an important position in the new building materials industry. The main equipment for production of silt sintered insulating brick is the vacuum brick extruding machine, the forming mold is the most critical part in it. The performance largely determines the quality of the brick. The structural design and other aspects of the forming mold are analyzed, and then systematically summarize the design and production requirements of the forming mold. The research status of the forming mold on vacuum brick extruding machine at domestic and abroad is reviewed. The main problems of forming mold are analyzed and the corresponding solutions are given, as well as the future developments of forming mold.

Near-stoichiometric lithium tantalite (LiTaO3) crystals were grown by the top-seed solution pulling method in congruent melt with the addition of K2O. The crystals were characterized by measurement of the ultraviolet absorption edge, ability of photo-damage resistance, and the domain structure analysis. Compared with the congruent crystal shows that, the ultraviolet absorption edge of the near-stoichiometric crystals has a blue shift towards a shorter wavelength and curie temperature is also improved; the domain structure of near-stoichiometric LiTaO3 crystals is hexagonal; and the photo-damage resistance of the crystals is greatly improved.

In this paper a simple eco-friendly wet-chemical way was mentioned to synthesize gold nanoplates. The prepared of the gold nanoplates was a seedless process that carried out by mixing HAuCl4 aqueous solution and Tannic acid (TA) solution at room temperature without the other surfactant and capping agents. The scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have been used to characterize the shape and composition the prepared gold nanoplates. The molar ratio of HAuCl4 and TA can control the shape and the size of gold nanoplates effectively. This research can provide a simple and eco-friendly way for the prepared gold nanoplates in aqueous solution.

In this study, 2024 Al alloy and AZ31B Mg alloy were brazing with mechanical stirring. The effects of brazing speed on microstructure and shear strength were investigated. The results show that oxide films on Al base metal surface broken completely at lower brazing speed. The continuous IMCs layer was broken into thinner one and blocky IMCs distribution in filler metal more evenly at lower brazing speed. The shear strength value near Al and Mg interface up to 53.1Mpa and 41.5Mpa respectively.

The oxidation behaviors and kinetics of in-situ β-Sialon bonded Al2O3-C refractories were investigated by TGA techniques via isothermal oxidation experiments at different temperatures. The results show that the oxidation process of in-situ β-Sialon bonded Al2O3-C refractories can be divided into three stages: oxidation reaction rate controlling stage, reaction and diffusion controlling stage, and diffusion controlling stage. The oxidation rate controlled by the reaction rate has no obvious changes as the temperature increases. The oxidation rate controlled by the reaction rate and the diffusion rate together has a trend of decline, so is the oxidation rate controlled by the diffusion rate.

Berberine, a common drug, which is widely used in clinical medicine as inflammatory medicines, is rarely studied about its affection on non-target organisms in recent researches. To evaluate the eco-toxicity of berberine in mouse heart cells, biochemical responses including oxidative damage and changes in the activities of antioxidative enzymes catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and malondialdehyde (MDA) induced by berberine were investigated in mouse heart cells. 7.5, 15, 30, 60 and 120 mgkg-1 berberine was added to mouse heart cells respectively. Compared to the controls, the damage, tail DNA content (%) , tail length and tail moment went up respectively in dose-effect manner following the rising berberine; As the content of berberine increased, the activities of SOD, CAT and POD were gradually decreased and the concentration of MDA was gradually increased. Compared to the controls, the change tendency showed significant differences (p

This paper briefly introduces the CNC hand wheel and analyzes the working principle of CNC hand wheel. Here make a circuit board based on the hardware design and software implementation. Simulation results were presented in this paper. Using this method can eliminate the interference of the hand wheel signal effectively and record the pulse signal of hand wheel accurately, and have achieved good results in FOXCONN.

This paper introduces a kind of physiological signal detection instrument based on FPGA. The system uses FPGA as the core, SC0073 as the sensor, the signal amplification, filtering, A/D conversion, and finally the signal does a digital signal processing in FPGA , and under the control of FPGA, displayed on the LCD screen in time. Results show that the system is stable and have a good performance.

Peat soil, (peat and peat soil) has high organic matter content, large void ratio, high natural water content, low shear strength, compressibility, strong characteristics, is a kind of special soil is very weak. But with the development of national economy, the peat soil and engineering construction is more and more close, especially for Kunming area, huge number of peat soil. So the way is very necessary to strengthen the peat soil.Based on typical engineering geological characteristics of peat soil in Kunming region, by adding fly ash, cement to verify the superiority to improve the performance of peat soil strength. Dissolution method is used to determine the degree of reaction of fly ash, peat soil is studied in the degree of reaction of fly ash and admixture, the relationship between parameters such as age, and the correlation model was established

According to the changes of the mixed gas flux ,porosity and burner structure,we measured the contents of CO, HC and Nitrogen Oxides in the harmful emissions of the methane burned in the micro combustor.In the micro scale, because the structure size of the burner is small, the combustion space and time is limited, CO and HC emissions are the products of incomplete combustion, nitrogen oxide are the products in local high temperature and oxygen enriched conditions.

Vibration exists widely in people's life and production. Modal analysis for vibration system help to improve the running quality of the mechanical structure and prolong service life. This paper build a new discrete multi-freedom model to calculate the flexibility matrix of simple supported beam, and then use the flexibility matrix to calculate its modal parameters with matlab. In order to prove that the result is correct, this paper use classical continuous vibration theory to calculate the normal modal parameters, finding that the two results are basically the same and as the more discrete number, the result of discrete multi-freedom model more close to the result of continuous vibration theory. In view of this, the new discrete multi-freedom modeling method is proved to be true, and it also can provide the discrete modeling reference for modal analysis of complicated mechanisms.

From the concept of knowledge management, this paper points out the importance of aviation equipment maintenance knowledge management. Specific countermeasures are presented by the three elements of knowledge management which are personnel, organization and technology as the main line.

For improving the conditions of single function, low testing precision, complex operation that exists in the tests of leaf spring testing machine, and on the basis of relevant provisions GBT19844-2005 leaf spring, a test bench for leaf spring with multifunction is designed. Through the structure analysis of leaf spring, a structure scheme of test bench named gantry type is put forward, combined with the testing requirements of the national standard and the spring stress characteristics, the hydraulic loading system and PID(Proportion Integration Differentiation) control system is proposed as well. By this test bench, experiments of the leaf spring for "permanent deformation, stiffness, fatigue" and other aspects related can be conducted, with shorter experimental cycle and higher experimental precision.

As a typical application of Internet of Things (IoT), the issue of protecting security of WSN will be an important problem effecting the expansion of IoT. Since the nodes of WSN are always arranged in an open environment, they are easy to be captured by adversaries. Traditional detections of capture always judge the attack by comparing the absence time of nodes with a certain threshold. In actual applications of WSN, the uncertainty of radio environment and transmission ability of nodes incurs problem of determination of threshold. According to the quality-quantity uncertainty conversion ability of Cloud Model, it is practical to calculate the absence time of nodes in a certain area, to establish the cloud of wireless environment. The threshold will be determined by cloud of wireless environment. Then, Cloud-based First Stage Detection (CFSD) is proposed to detect the node capture attacks in WSN. Simulation results verify that this approach can improve the accuracy of detection and decrease the false alarm probability.

With the rapid growth of Internet penetration, it is the disclosure problems of network information that frequently appears .At the same time, the problem of Internet safety has been attached great importance to by the countries. Thus, it is of great significance to build an Internet safety supervision mechanism. Based on white box testing technology and black box testing technology theory of network security detection, this paper proposes a WEB interface detection algorithm based on Internet resources and sets up a safety assessment model for computer security and supervision mechanism. In addition, this paper also designs the algorithm experiment by taking the data detection which considers WEB as the connector for example. Through the algorithm experiment, the following conclusions are obtained: Network interface has a higher recognition rate for E-BPM-BM algorithm which has different types and different characteristics. Among them, registered network interface owns the highest recognition rate which is up to 98.46%. When the network test node matrixa0 is 9, its matching rate reaches the maximum, namely 0.97 9.

Concerning the steam induced draft fan renovation tendency in large coal-fired power plants, the economic and environmental benefit are analysed for certain 1036MW ultra supercritical units. Under the same generator output, despite the power generation coal consumption for the scheme with steam induced draft fan coal increased, the auxiliary power reduced significantly which results in roughly RMB 10,657 thousands yuan economic saving every year with about 1.9 years payback period of investment. Due to the power supply coal consumption saving, the annual amount of pollutants reduction of CO2, SO2, NO2 and dust are 4440.867, 16.462, 45.514 and 220.829t, respectively.

Along with the rapid development of China and its eye-catching economic take-off, industrial production has brought about increasingly enormous negative impact. Industrial residues (coal ash, iron-ore slag, phosphorous slag and ganister sand) have accumulated in large quantities, thus severely contaminating the environment and greatly restricting the sustainable economic development. This paper conducts research on microstructure of the industrial wastes that are massively applied in domestic architectural material industry, such as coal ash, (S95S105) slag powder, S75 phosphorous slag, micro-bead (ultra-fine coal ash) and the micro ganister sand so as to analyze its size distribution and particle appearance and introduce its functions and effect in concrete and other cement products.

NAND flash memory has been successfully employed in storage system due to its advantages such as performance, resistance, and capacity. NAND flash memory based solid state disk (SSD) has started to replace disk in numerous environments. However, the poor endurance offered by these SSDs continues to be their key shortcoming. To improve SSD endurance, we propose a static wear-leveling algorithm with variable threshold (WLVT). In contrast with traditional algorithm with fixed threshold, WLVT adjusts the value of threshold, so that each block can simultaneously reach the erasure times that the manufacturer gives when life of SSD is over. Therefore, available erasure time of each block will be fully utilized when SSD fails. Experimental results show that the endurance of the SSD is significantly improved.

Oil well casing damage is one of the security problems in petroleum engineering, it should be paid more attention in oil and gas development. Influence factors of oil well casing damage are very complicated, and the evaluation criteria of each influence factors are different. Therefore, for the assessment of casing damage, should be based on a comprehensive engineering and petroleum geology of the argument, using multi-criteria evaluation method to implement from the safety point of view. The development of multi-criteria evaluation method based on GIS oil well casing damaged isnt only consider the relative importance of each influence factor, but also fully consider the various factors of space walks and order of importance. With the help of IDRISI software, Jinzhou oil production plant in the 25 block as an example, calculating order weights and criteria weights, the comprehensive evaluation of damage to the casing pipe of oil well is made. By comparison of weighted linear combination method and the ordered weighted average (OWA) method, analyzes the ordered weighted average method advantage.

Microbubbles play an important role in the micromixing of micro-fluidic systems. However, there are few results in the literature about the mixing of the liquids caused by bubbles flow. The paper presents the numerical simulation of bubbles flow in microfluidic, which agrees well with the experimental results. The influence of velocity amplitude, frequency and phase difference on the mixing performance was investigated. The results show that the isolate bubbles as obstruction can improve mixing efficiency in the true straight microchannel, the bigger the velocity amplitude, and the higher the frequency, the better the mixing efficiency is, but the mixing efficiency has nothing to do with the number of bubbles and just benefit from the certain phase difference. With the other two parameter remains unchanged, the mixing performance achieves the best value when the velocity amplitude is 0.25m/s, the frequency is 25HZ, the phase difference is 0.25, respectively. The study referring to bubbles flow induced mixing performance is very important for many microfluidic devices.

Spacecraft surface charge and discharge is an important reason for the failure of the spacecraft in the space environment. This paper introduces the principle of spacecraft surface charging and discharging , from the spacecraft surface charging discharging phenomenon found to the harm of charge and discharge, elaborated the spacecraft surface charging protection method.

The conceptual introduction of the service network and its function in passenger flow assignment are given. Based on the summary of the related research results, the service networks are divided into two classes as the matrix type and the network type according to the different construction methods. The modeling principles and methods of the network type service network are then proposed. The methods are explained in three aspects including node modeling, segment (or arc) modeling, and partial network modeling, which can, for a certain physical network and a certain line plan, construct the virtual service network that is required by the passenger flow assignment process. Corresponding modifications are required when using these methods in specific researches.