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YL10.2 and YF06 are ultrafine-grained cemented carbides, and grinding experiments were carried out with resin-bonded diamond grinding wheel. Based on measured grinding force, surface roughness and SEM topography, experimental results were analyzed; grinding forces and depth of grinding approach linear correlation; and the grinding force of YF06 is greater than that of YL10.2 in rough grinding, but the grinding force increases significantly if depth of cut is greater than a certain value in finish grinding. The trend of machined surface roughness looks like “V” type with the increasing of depth of cut; the material removal behavior of ultrafine-grained cemented carbides in grinding was observed; the ploughing and fragmentation exist simultaneously on the ground surface, and the dominated material removal behavior depends on the grinding parameters or chemical composition of workpiece.

In this paper, according to 1990-2011 Shanghai water pollution data, using co-integration test, error correction model, Granger causality test, impulse response analysis and variance decomposition analysis, from the perspective of temporal dimension, we explore the long-term equilibrium and dynamic mechanism between water pollution and economic growth in Shanghai. We have found that: the index of water pollution in Shanghai grow fast in particular wastewater emissions, economic growth depends on water environment pollution, and economic growth bring enlarging water environment pressure at the same time.

According to the project interface risk classification including the physical interface risk, the contract interface risk, the tissue interface risk and the information interface risk, the integrated management model of project interface risk was put forward, which focused on the three dimensions: time dimension, relational dimension and information dimension. The project interface risk management system was developed, which consists of information subsystem, organizational subsystem, resources and support subsystem, and dynamic management subsystem. The system implements integration of project risk management from the perspective of the interface, and by using the system managers can foresee the exact location of the risk occurring or may occur.

Takovite, a kind of hydrotalcite-like compounds (HTlcs), was used for boron removal from water. It was prepared by coprecipitation method and characterized by X-ray diffraction technique (XRD). The equilibrium time of boron sorption by takovite as well as its boron uptake capacities was determined by the reaction kinetic experiments and isotherm sorption experiments. The effects of experimental conditions on boron removal efficiency were also evaluated. Generally, the boron uptake by takovites increases with increasing initial boron concentration in solution. The isotherm sorption data match well with the Freundlich model, indicating that the anion exchange contributes a lot to solution deboronation. Moreover, at higher temperature, greater boron removal by takovite was observed. As compared to calcined takovite, uncalcined takovite has better performance in terms of boron uptake, since the structural restoration of calcined takovite didnt happen during its contact with boron-containing solution, which is quite different from the behavior of other HTlcs as reported.

A new method for producing titanium and titanium alloys was studied at this paper. The experiment results indicate that Na2TiO3 could be synthesizing by heating at 450°C using NaOH and TiO2 powders.Metallic titanium was observed in XRD pattern of the electrolytes after experiment by means of constant-current electrolytic Na2TiO3 in a CaCl2-CaF2 melt at 850°C.Thendepending on the electrolytical residua,titanium aluminium alloy could be obtained by calcining with Al powders.

This study developed an evaluation model for the level of rail transit service based on the matter-analysis theory. Firstly, an evaluation system of rail transit service level which contains 14 indicators was proposed. Secondly, the evaluation model based on the matter-analysis theory was constructed and the key process was proposed. Whats more, the weights of indicators were calculated using AHP method. Thirdly, by calculating the degree of membership and interrelation value of evaluation indicators with regard to evaluation levels, the RT-LOS and its trend are judged. Finally, a case study of Xi'an Metro Line 2 was conducted to verify the model.

In China, with the accelerated urbanization and the rapid growth of urban population, potential urban emergency risk factors gradually increased. Therefore, how to forecast the urban emergency events seems to be important. This study elaborated the mechanism of catastrophe theory and grey forecast method, established the grey cusp catastrophe model according to further research. An empirical analysis on Chinese urban traffic accident forecast was made by this model through four indicators: the number of occurrences, the number of deaths, the number of people injured and direct economic losses. By operating the model with data from 2002 to 2006, the accuracy is verified. Based on data from 2002 to 2011, the model result shows that the next traffic accident occurrence catastrophe will occur in 2015-2016, the next death number catastrophe will occur in 2012-2013, the next injured number catastrophe will occur in 2018-2019, the next direct economic loss catastrophe will occur in 2014-2015.

This study developed an evaluation model of freeway traffic safety facilities system. Firstly, an evaluation system of freeway traffic safety facility was proposed. Secondly, an evaluation model was proposed based on attribute recognition theory. And the evaluation result was identified according to the attribute measure value of single index and the comprehensive attribute measure value of multiple indexes as well as the confidence criterion. Thirdly, the weight of each indicator was decided by variation coefficient. Finally, A case of TAI-GAN freeway (K1+242~K3+259 segment) was conducted to verify the feasibility and effectiveness of the model.

This paper study was commenced to treat fatal contamination at the Er-Jen River, supplied water for agricultural irrigation, aquaculture and industrial in Kaohsiung and Tainan Area, when the Sixth River Management of Water Resources Agency (WRA) developed the project to build flood embankment. The fatal contamination was throw into the discard by illegal manufacturer which discarded the wastage of printed circuit boards, toxic heavy metal contained sludge, and waste aluminum slag. The treatment project was conducted by Industrial Technology Research Institute (ITRI) on preliminary tests, cleanup planning, and process supervision to ensure contamination removal, flood protection, and landscape improvement. The accumulative volume cleaned and screened on this site reached 45,159 cubic meters, whereas 378.25 tons of waste printed circuit boards, 12,833 tons of toxic heavy metal contained sludge, and 31,000 tons of general industrial wastages. The waste printed circuit boards through stripping/acid washing and screening, there are 334.653 tons valuable (including 0.143 tons of copper and 334.51 tons of wire casting materials) from the recycle extract and 43.597 tons of wastes that were not valuable for reutilize. Toxicity characteristic leaching procedure (TCLP) tests were conducted on the site after cleanup to verify the treatment work successful, because the rate of contamination removal was greater than 90%.

This paper presents a new direction-of-arrival (DOA) estimation for wideband sources, using fractional Fourier transform with fitting angle (F3A). Unlike other coherent wideband methods, the new method does not require any preprocessing for initial values and decomposing into narrowband components. This new technique estimates DOA by rotating the time frequency plate with the fitting angle to fit the time frequency distribution approximately. The algorithm can be applied to arbitrary shaped one dimensional or two dimensional arrays. The signal frequency can be higher than the frequencies in many wideband algorithms. The performance of this wideband technique is compared with that of the new method through simulations. The simulations show that this new technique performs better than others, while this algorithm does not apparently vary with signal-to-noise ratio (SNR).

This paper proposes a new algorithm for joint estimation of Directions-Of-Arrival (DOA’s) and polarization parameters of the single electromagnetic vector sensor. Based on the cyclostationary properties of the signal,the algorithm uses minimum norm method to strike the signal steering vector solution, and then gets the estimation of DOA and polarization parameters. Besides limiting the distribution of additional stationary noise and interference signals on various frequencies, this algorithm also restraints the estimation error of the noise subspace singular vector with outstanding results. Computer simulation verified the effectiveness of the algorithm.

To mimic the alveolar bone and periodontal ligament interface, a chitosan(CS for short) composite polysaccharide scaffold was fabricated which was cross-linked with sodium alginate(SA for short). The conditions of physical crosslinking in the scaffolds were discussed. By characterization after biomineralization, it turns out that pH=5.0 and 40min crosslinking time can make for crosslinking. Better crosslinking makes the material more antiswelling and give more compressive strength. In the other hand, the biomineralization can improve the physical properties of the material. We hope that after further research it can come to a scaffold material with good properties.

Environment protection is one of the core tasks of the higher colleges. Under the condition of the unchanged capital investment, how to make the capital efficiency of the environment protection maximized still has no mathematical models for references at the present time. In this article, by using the views of the system theory and the related methods of mathematics and statistics and combing the empirical data of the higher college construction

Anion exchange membranes based on poly(aryl ether oxadiazole)s (FPAEO) were prepared by quaternization of bromomethylated FPAEO with N-methyl imidazole. The structures of the obtained polymers were characterized and confirmed with 1H-NMR measurement. The physical and electrochemical properties of anion exchange membranes were also studied. The conductivity of FPAEO-xMIM membranes were almost higher than 10−2 S/cm at room temperature. In addition, TGA revealed that the AEMs based on imidazolium salts have excellent thermal stability. The experimental results suggested that the obtained AEMs may be potential membranes for anion exchange membrane fuel cells

A series of fluorinated poly(aryl ether oxadiazole)s (FPEO) were synthesized and brominated with N-bromosuccinmide (NBS) which were then functionalized with quaternary guanidinium to get fluorinated anion exchange membranes （AEM）with pendant quaternary guanidinium Groups. The structure of resulting polymers was characterized by FTIR spectroscopy. The properties of the obtained membranes were investigated in terms of ion exchange capacity (IEC), swelling ratio, area resistance and vanadium permeability. The results showed that the novel anion exchange membranes possess much higher selectivity in VRB system. The permeation rate of vanadium ions of GFPEO is 0.21×10-7 cm2min-1 which is much lower compared with that of Nafion.

The reduction ratio was compared between the Pidgeon process and the aluminothermic reduction process with CA2, CA, C12A7as the main production in the residue. The results of XRD show that the main phase in the reduction residue is CA2, CA, C12A7and Ca2SiO4, respectively. Consideration of the efficiency of extracting magnesium, the aluminothermic reduction process which is CA2as the main phase in the reduction residue, is the best one.

The rapid urbanization in China has caused significant urban land use changes and extensive urban growth these years. That has led to a dramatic decrease in arable land and would challenge the national food security. To understand the anthropogenic driving forces of urban growth and find out effective control methods, this study established the Hierarchical Liner Model (HLM) to explore the influence of such factors including society and economy, population, and industry development. On the base of factor analysis and HLM, the decomposition of the affecting factors for urban growth was performed, it visually shows that the social retail goods, public transit passengers, and nonagricultural populations significantly drove the urban growth in China; the tertiary industry development has weak effects on urban growth. By weighting the role of the anthropogenic factors on urban growth, some advices were given at last, and it could provide possible management options for the government to mitigate the excessive urban growth in the near future.

Overlaying pinch roller has higher surface hardness. If the overlaying technology is improper, small circumferential cracks may occur on the welded surface and even peel off. From failure analysis, it is indicated that the contents of C, S, and O were higher around the cracking area in the deposited metal. Optical microscopic observation shows that some cracks grew along the direction of columnar crystals and residual austenite. Due to high content of inclusions and austenite in the deposited material and poor plasticity of the deposited metal, small cracks are easy to be found at the defect such as blue flecks. In addition, a large number of cracks intersect on the deposite surface, resulting in large peeled area.

In the present work, effect of vanadium on mechanical and thermal fatigue resistance of Cr5 deposited metal is investigated. It is found that hard phases with rich vanadium are mainly distributed at grain boundaries. Vanadium affects the high temperature tensile strength and thermal fatigue cracking obviously. With the increase of vanadium content, high temperature tensile strength of deposited metals shows a initial rise up, then drop for more than 0.54 wt.% V. Toughness and high temperature plasticity are increased up to 0.26 wt.% V, then drop up to 0.89 wt.% V, then toughness and plasticity increase again. Moreover, the thermal fatigue crack length shows a initial decrease up to 0.26 wt. % V, then slightly rise up for 0.89 wt.% V, then crack length shorten again. It is expected that the optimal vanadium content is in a range of 0.18~0.26 wt.% for resisting the thermal crack growth. Fractographic observation shows that the thermal fatigue cracks mainly are transgranular growth. It is felt that the crack length is closely related to microstructure, oxidation resistance, toughness and high temperature plasticity of the deposited alloy

This article put forward a kind of PID compound control algorithm, the arithmetic is the integration of fuzzy control technique and PID control technique, it possesses both the flexible and strong robust advantage of fuzzy control and the precise character of PID control. A simulation study of the system shows that the algorithm is of reliability, high precision and strong ability of anti-interfere and robustness.

ERP (Enterprise Resource Planning) is a kind of advanced management method and ideological system, which is an effective tool to improve operating efficiency. In reference to the domestic and foreign relevant research results, this paper attempts to find a set of evaluation index system and method, which is suitable for small and medium-sized enterprises in China implementing ERP system performance evaluation according to characteristics. Then use AHP to determine each index weight and evaluate comprehensively ERP implementation performance of small and medium-sized enterprise employing the fuzzy comprehensive evaluation method. This can provide ERP project methodological guidance and help enterprise to carry out the scientific decision, improve the success rate of ERP implementation, and promote the process of ERP in our country popularity.

Laboratory-scale carbon anodes were produced by a new method of high-temperature mould pressing, and their physico-chemical properties were studied in laboratory. The results showed that the bulk density of carbon anodes produced by high-temperature mould pressing are 1.61-1.63g/cm3, they are higher than industrial carbon anode by 0.06 g/cm3, but the specific electrical resistance is higher and crushing strength is lower.

In signal processing, a frequently encountered problem is harmonic retrieval in additive colored noise, especially false peaks existence in harmonic signal peaks. The purpose of this paper is to develop an efficient approach to clear the false peaks based on cross-high-order spectral QR decomposition approach. Simulation results indicate that spectral density curve is smooth without false peaks existence. The methods have better in resolving power and performance than previous MUSIC approach. Thus, this approach is ideally suited for harmonic retrieval in additive colored noise and short data conditions, and is also accurate to estimation signal parameter in hybrid colored noises.

Graft modification is a common means to improve performance of natural polymers. Graft modification of collagen with acrylonitrile in zinc chloride aqueous solution was developed to apply in improvement moisture absorption of synthetic fiber. Polymerization yield, graft ratio and graft efficiency increase at first and then decline following monomer concentration, they reach the top when monomer concentration is 7.0 wt%. Graft ratio and graft efficiency increase at first and then decline following initiator concentration, they reach the top when initiator concentration is 0.2 wt%. Polymerization yield consistently rises with the increasing initiator concentration. Polymerization yield, graft ratio and graft efficiency drop with the increasing collagen concentration. The optimal reaction conditions are: reaction time , 90min; reaction temperature, 60°C; monomer concentration, 7.0 wt%; initiator concentration, 0.2 wt%.

In this paper, there are two kinds of material (cermet and cemented carbide) to be used. Different grinding conditions were performed for evaluation of RMS of acoustic emission(AE) signals and understanding the effect of each grinding parameter on AE RMS during grinding process. A kind of on-line monitoring method based on wavelet analysis and acoustic emission was raised and the nonlinear relation model between AE RMS,wavelet energy coefficients and wheel passivation state was built. During the process,the wavelet analysis method was used to decompose the original signals for extracting wavelet energy coefficients. The results of experiments indicates that AE RMS increases with increasing table speed;The corresponding relation between AE RMS and table speed is good and could take the table speed as the main parameter for studying wheel passivation state. As a result, the nonlinear relation model can monitor the wheel passivation degree on-line accurately through training. This provides a kind of viable method which has very high practical value for confirming the wheel dressing cycle.

PTFE suspension latex and PVA solution are blended at different ratio, and the rotary rheometer is used to test the rheological properties of these solutions. The result shows that both PTFE suspension latex and PTFE/PVA blended solution are all shear thinning fluid; with increasing shear rate, apparent viscosity decreases; with increase of PVA content in blended solution, apparent viscosity and Non-Newtonian index increase, and spinnability of blended solution can be improved; with increase of temperature, the apparent viscosity decreases.

Dodecyl benzene sulfonic acid (DBSA) doped polyaniline (PANI) grafted MWNTs (PANI-g-MWNTs)/Epoxy composite were prepared by aniline in situ polymerization in the presence of phenylamine groups contained MWNTs followed by solution blending and mould casting. Phenylamine groups grafted on the surface of MWNTs via amide bond join in the in situ polymerization and MWNTs are encapsulated by PANI coatings forming a core (MWNTs)-shell (PANI) nano-structure. DBSA doped PANI coatings swell in tetrahydrofuran (THF) and core-shell nano-structures are stabilized in epoxy solution, which is in favor of MWNTs dispersion in epoxy resin and formation of a homogenous MWNTs/Epoxy composite. After DBSA doped PANI-g-MWNTs are introduced in Epoxy, initial curing and exothermic peak temperatures as well as curing reaction enthalpy decrease, which indicates addition of DBSA doped PANI-g-MWNTs promotes curing reaction of Epoxy. Tensile strength, Young’s modulus, elongation at break, flexural strength and flexural modulus of the composite are improved by 71.7%, 42.3%, 99.8%, 55.01% and 39.86% compared with Epoxy, respectively.

Based on characteristics of environmental impact of railway construction projects, the paper drew on experience of environmental impact assessment (EIA) projects, carried out preliminary EIA on China's mid-long term railway network plan from macro perspective according to planning requirements, and discussed the key points of EIA on guiding special planning.

Using the interactive software, this study was mainly focused on developing a 3-D joint shape after the as-reflowed soldering which is the one of chief factors affecting the reliability. From the results, the soldering process can be simulated and observed directly. By changing the various conditions and constraints, such as surface tension, wetting angle and specific gravity, it makes a comparison between the simulated result and the experimental one. The simulated parameters are based on those of the traditional eutectic Sn-Pb solder. After slicing and comparing the different profiles of the simulated shape, the 3-D simulated geometry fits well with the experimental one.

Sergeants’ teaching under the condition of professional education is the new problem in the construction of army transformation. This paper gives an analysis of the current situation of sergeants’ mathematical teaching under the condition of professional education and offers the corresponding suggestions, which provides reference for mathematical teaching staff working in education institutions.

In order to simulate accurately the formation process of the keyhole in laser deep penetration welding. Multiple reflection and Fresnel absorption are implemented simultaneously with the ray tracing technique in the keyhole. With all the governing equations including continuity, momentum and energy equation, the VOF method is adopted to trace the free surface of the molten pool. Simulation results are compared with the experimental ones to verify its validity.