Search

Fe62 alloy coating was fabricated on the surface of #45 steel cutting edges with 2kW all-solid-state laser and powder feeding device. The substrate and forming layer are characterized by optical microscope and scanning electron microscope for microstructure, and tested by micro-hardness tester for micro-hardness. The results show that the forming layer combined with the substrate metallurgically. The microstructure of substrate is eutectoid ferrite and pearlite. The microstructure of layer is uniform and compact, with hard precipitation. The content of Cr, the hard phase generated element, at the grain boundary, is higher than that of grain inside and many hard phases were generated at the grain boundary. Compared with the substrate, the micro-hardness of forming layer increases by about 2 times. All these results show that application of laser additive enhancing technology in the field of cutting tools has larger potential.

Aiming at the problem of the complicated process, the low precision and efficiency of crack detection and key geometric feature of the circular saw blade, the quality detection system of the circular saw blade based on the nondestructive testing and laser measurement technology is studied. By using the laser measurement technology and optimizing the data processing method, the face runout, the thickness of the circular saw blade are measured. The crack defects in the tooth root region of the circular saw blade are detected by eddy current nondestructive testing technology. The system achieves the radial detection of 1mm radial sawing, the detection accuracy of the round beating is> 0.03mm, and the thickness measurement accuracy is> 0.005mm.

Silicon carbide (SiC) is widely used in terrestrial and space applications because of its good mechanical, thermal and optical properties. Nevertheless, traditional grinding and polishing technologies cannot meet the machining requirements due to the high hardness and brittleness. In this paper, Inductively Coupled Plasma (ICP) is utilized to process the SiC optics. The effects of different processing recipes on the removal rate and temperature are investigated. The results show that the removal rate almost keeps stable with processing time and changes with the flow rate of plasma gas, reaction gas, the ratio of CF4/O2 and the power. The input power and processing time are the two main influence factors on the processing temperature.

The natural frequency of model was analyzed by finite element software in the first and the result was consistent with the experience formula. Then, time history of ground motion was inputted. The seismic capacity of the structure was analyzed by parameters as structural damage, seismic shear and acceleration. Structural damage in seismic “three levels” and the results of seismic appraisal were consistent. The injury site structure put forward strengthening measure of circle beam and structural column. Scientific basis and technical support for seismic strengthening were provided for Tianjin Western-style dwellings.

In order to explore the new way to precision machining of the cylindrical, ELID precision mirror grinding technology are employed to precision ultra-precision grinding experiments. Given ELID precision mirror grinding technology has effectively solved the basis of many of the typical flat-precision machining difficult materials and efficient processing, through the conversion process equipment tools, and optimization of process parameters, obtained when the wheel speed in 16 ~ 20 m / s, when the grinding depth 10μm, cylindrical grinding state is best, which could obtain Ra0.025μm surface roughness of the machined surface.

This paper analyzed the large diameter Fresnel lens mold machining mechanism based on modal test methods .The design and mold machining principle of Fresnel lens were introduced . Explored the cutting speed and feed on chip formation process. The results show that: the material strength and plastic brittle have significant impact on chip morphology in the H62 brass mold processing, an improvement of material strength with the increase of strain rate and the evolution process of the chip can be divided into: ribbon cuttings, serrated chips, cell chips.

The electrolytic in-process dressing (ELID) grinding technology was adopted for precision grinding experiments of volume fraction of 40% of SiCp/Al composites, obtaining the machined surface roughness of Ra0.030μm. Studying the forming mechanism of processed surface, analyzing several typical grinding surface defects, summarizing the grinding characteristics and removal mechanism of SiCp/Al composites.

In this paper, according to the principle and the existing technology of ELID grinding, we use the existing lapping machine of Wenzhou Runsheng ceramic water valves factory as the experiment platform to develop an ELID lapping process system. Then utilizing ELID ultra-precision lapping technology to process alumina ceramic seals obtained a good effect. The roughness of processing samples reached about 15nm which was demanded by the enterprise, the efficiency increased 60% and the cost reduced 50%. On this basis, we designed an ELID lapping prototype. It laid a solid theoretical and practical basis for the production of ELID lapping machine in the future.

The electrolytic in-process dressing (ELID) grinding technology was adopted for ultra-precision grinding experiments of SiCp/Al composites; the machined surface roughness can obtain Ra0.030μm. The experiments show that: with the grinding wheel rotation speed of 1500r/min, the grinding depth of 0.1μm, and feed speed of 2m/min and using W5 cast iron bonded diamond grinding wheel, the grinding effect can achieve optimal.

Atmospheric Pressure Plasma Processing (APPP) of silicon-based optics and wafers is a form of chemical etching technology developed in recent years. The material removal rate is comparable to those of conventional mechanical processing methods in precision fabrication. Moreover, there is no mechanical contact or physical loading on the substrate surface, hence no surface or sub-surface damages are induced. Inductively coupled plasma is one realization of APPP. In this work, inductively coupled plasma torch is used to generate plasma and excite etchant particles at atmospheric pressure. These active particles then diffused to the workpiece surface, react with its atoms to form volatile products. The activity and number of particles in plasma are influenced by processing parameters such as input power, distance between nozzle and substrate surface, flow rate of plasma gas argon and precursor gas CF4. These factors have various impacts on material removal rate. Processing experiments are conducted on fused silica to investigate the parameters’ influences on material removal rate. The basic interaction between substrate surface and plasma is illustrated, then the relationships between processing parameters and material removal rate are analyzed. From the experiments some trends are derived. Material removal rate rises with the increase of power and flow rate of CF4, whereas decreases with the increase of processing distance, etc. The etching footprint is proved to be near Gaussian-shaped and believed to have high potential for deterministic surface processing.

Mind sports games is rose in recent years, which is the comprehensive sports event taking the chess sports as the main part, and it is a perfect combination of human intelligence and sports art. Due to a simple history of mind sports games, there exists some problems that are the imbalance of development, lack of funds, and event organization difficulty, which has restricted the rapid development of mind sports games. Aiming at the problems of mind sports games encountering in the development, the paper first proposes the coupling development mechanism for the organization of mind sports games and its development mechanism, and then establishes the model of development mechanism based on the coupling reduction mechanism, and the model has been made simulation analysis. At last, the results show that the application of this coupling model can find the bottleneck of the development of mind sports games, so as to open the breakthrough point for its development, and to improve its development level.

Cloud computing represents one of the most significant shifts in information technology many of us are likely to see in our lifetimes. It offers an innovative business model for organizations to adopt IT services without upfront investment. Cloud computing moves the application software and databases to large data centers, where the management of the data and services may not be fully trustworthy. Security is one of the major issues which hamper the growth of cloud. The security for cloud computing is emerging area for study and this paper provide technical components of cloud computing and security idea in terms of cloud computing based on analysis of cloud security treats.

Trusted computing is a hot topic of information security technology research nowadays. It was developed based on computing and Information Systems. At the same time, business processes for e-commerce and Web service applications, suppliers and customers define a binding agreement or contract between the two parties, specifying quality of service (QoS) items such as products or services to be delivered, deadlines, quality of products, and cost of services. The management of QoS metrics directly impacts the success of organizations participating in e-commerce. In this paper, we discuss the present situation about QoS in the environment of trusted computing. It describes the factors related to each attribute, as well as possible tradeoffs and existing efforts to achieve that quality. The paper also discusses key issues in services level agreements that are used to contract the level of services quality between service providers and users.

Aggressive train signal belongs to typical accidents in the process of train running; it has many influence factors, widely related departments and complex results. In this paper, we carry on the qualitative and quantitative analysis on the typical accidents using FTA technology, to estimate and calculate the structure, probability and critical importance degree. The affecting factor of the typical accident to analysis deeply. Then the analysis conclusion is carried out and the prevention strategies of the typical accident are given.

This paper describes the analysis of the chip formation mechanism in mold machining process of large diameter Fresnel lens based on the ABAQUS finite element simulation software and modal test methods. Combined with the material constitutive relation and material failure criteria etc, a two-dimensional orthogonal cutting model was established and the chip derived from the simulation was compared with the chip from modal test, with a consequent verification of the feasibility of simulation chip model. The simulation contributes to an investigation into the effects of the cutting speed on chip formation process. The results show that: the material strength and plastic brittle have significant impact on chip morphology in the H62 brass mold processing, and material strength will improve with the increase of strain rate, the evolution process of the chip of material plastic reduction can be divided into: ribbon cuttings, serrated chips, cell chips.

In order to improve the level of production management and information development of textile industry, firstly the paper analyzed the hardware and software structure of jet loom monitoring system, then carried out related research on the information management of textile industry, introduced the related techniques, implemented the real-time monitoring and control based on CAN bus, data gathering and Winsock technology. The practice has proved that the loom network monitoring information system based on the industrial Ethernet has improved greatly the efficiency of production, and building network is simple, the development and maintenance are easy, and the performance is good and so on, which can provide better realistic instructions on realizing the standardization of communication, automation and information of the textile industry.

With the development of automotive electronics industry, the car which has electronically controlled air suspension is gained wide application. we designed an electronic control unit of automobile electronically controlled air suspension system (ECAS) including the hardware system which include the speed signal collection and processing circuit, the solenoid valve drive circuit, the CAN communication design, height detection circuit, Freescale microcontroller etc and the control strategy while propose some the basic ideas, based on Freescale microcontroller, after introducing the composition and the principle of electronically controlled air suspension. The ECAS can improve vehicle fuel economy, ride comfort and traffic-ability.

An important new technology has recently been developed that will revolutionize trust and security for online transactions. Conventionally, most of the security-relevant functions are concentrated within the operating system. Often, these functions, especially those dealing with access control, are commingled with object management functions. This article, abstracted from a new book on the subject, explains the key concepts and the exciting potential of Trusted Computing Platforms (often abbreviated to Trusted Platforms). We discuss access control in multilevel database management systems applies and illustrate the main applies of access control based on Trusted Computing in the LogicSQL database system.

The influence of tool rake angle, feed rate and back cutting depth on the surface roughness and surface waviness of KDP crystal were studied when processing KDP crystal in the way of horizontal fly cutting. Comparing with the influence laws of vertical single point diamond fly cutting, we analyzed the respective advantages of the two kinds of cutting processing methods and summarized the similarities and differences of the influence rules that cutting parameters on surface quality under the two ways.

The excitation system is an important component element that influences the dynamic behavior of alternators. However, when the two-quadrant H-half bridge converter is used in the exciter field current closed-loop control system, there will be some problems of nonlinearity. To prevent the converter from working in the nonlinear area, the working conditions of linear and nonlinear area of H-half bridge converter is discussed firstly in this paper. And then it is verified by the simulation results.

This paper presents a two-quadrant H-half bridge converter used as the field current amplifier of ac exciter in the synchronous generator brushless excitation system (SGBES). Differing from the conventional amplifier, the exciter field winding can be supplied with positive and negative voltage to help increase the response speed of the excitation system. However, there will be some problems of stability when the converter is used in the current closed-loop control system. To prevent the converter from working in the unstable area, the stability of the linear area has been analyzed. Finally, it is verified by the experimental results. These can provide a valuable theoretical and practical basis for the design of parameters for the current closed-loop control system used by the converter.

The electrolytic in-process dressing (ELID) grinding technology was adopted for ultra-precision grinding experiments of GCr15 bearing steel. The experiments show that: grinding depth, electrolysis gap and wheel peripheral velocity are the main factors to affect the surface quality. With the electrolysis gap of 0.5mm, the grinding depth of 0.1μm, and the wheel peripheral velocity of 18m/s, the grinding effect can achieve optimal and the machined surface roughness can obtain Ra0.006μm.

In this paper, the ultra-precision mirror polishing technology was adopted for mirror processing experimental study of Aluminum Alloy mobile phone shell. The experiments show that: polishing pressure, Grinding disc speed, the texture and hardness of polishing pad and abrasive particle size are the main factors to affect the surface quality. Through to optimize these parameters matching combination, can effectively improve the surface quality and reduce the surface roughness and obtain surface roughness is Ra0.026μm.

In this paper, aqueous methanol (methanol concentration 1000 mg·l-1) degradation was studied by using UV/Fenton, and effect of methanol degradation was evaluated with COD removal rate. When pH was determined, H2O2 dosage, Fe2+ dosage and reaction time were investigated by single factor test, respectively. In the orthogonal experiment, UV/Fenton was used to deal with wastewater of 1000 mg·l-1methanol, the order of the influent factors on COD removal was: H2O2 dosage > reaction time > Fe2+ content. Under the optimal condition (6%H2O250 ml·l-1, Fe2+ 0.9 g·l-1, reaction time 60 min), 95.77% COD removal rate was obtained. In addition, a comparison of UV, Fenton regent and UV/Fenton system indicated that UV and Fe2+ had synergistic effect on catalytic decomposition of H2O2, and reaction time to obtain the highest COD removal was shorted 10 min when UV/Fenton was used.

The key factors involved in the train derailment on bridges or lines have been discussed in this paper. Also the statistics of derailment accidents with an upward trend occurred in recent years, all over the world, are listed. Analysis of the reasons for train derailment, geometric criterion and mechanical mechanism of train derailment are discussed. Then the authors make an analysis of difference of train derailment between bridges and lines from five aspects. The conclusions have been drawn from the comparative analysis of train derailment involved in lateral stiffness, derailment time history, flow field, motion equation and resonance. There is no characteristic of time history for a certain distance on line derailment. And the mechanical characteristics of vehicle-bridge system are more complicated than the vehicle-line system under wind loads.

In order to grasp the related information and parameters needed by the tree growth, and management, establish the authentic decision-making model of tree growth management using the effective resource information, the resource information of tree growth management are investigated from the perspective of ontology and knowledge base technology. The paper introduces the ontology and knowledge base technology, adopts the knowledge organizing pattern based on ontology, studies the structure and technique of knowledge of tree growth management, the ontology is regarded as the knowledge organizing pattern to establish the open knowledge base of tree growth management, and constructs the management model of tree growth. Practice has proved that the research and application of ontology in the resource information of tree growth management has important value for the model construction of tree growth management, achieves the sharing of resource information of tree growth management.

The circuit board fault detection based on infrared technology is a new non-contact and non-destructive method. During studying the system structure of circuit board fault infrared detection, the author analyzes the key influence factors of infrared information extraction, gives a new fault diagnosis method of infrared image processing and pattern recognition, then points out the problems in the practical application of fault detection instrument, provides the reference for the further study of the technology.

In order to study the influence of interface bond condition between new and old cement concrete pavement on overlay performance, the three-dimensional finite element model of the airport double-layer pavement was established. The pavement overlay's load stress and deflection were analyzed, the coupling coefficient between new and old cement concrete pavement was calculated based on the bottom of overlay deflection basin shape factor. The results show that the coupling coefficient reflects the degrees of interface bond condition well. Poor interface bond condition increases the overlay's load stress and deflection. The points that more closely distance from the wheels load center, the bigger the pavement overlay's load stress and deflection is. Therefore, more attention should be paid to the interface bond condition during the airport pavement overlay's designs and constructions.

This paper uses a total-factor framework to investigate energy efficiency in 22 major energy consuming countries, which consuming more than100 million tons of oil equivalent in 2010, including 14 OECD countries and 8 non-OECD countries. Two DEA models, total-factor energy efficiency model and energy-saving energy efficiency model, are used in this article to analyze the China’s energy efficiency for impersonality and comprehensive, and to find the energy efficiency difference between china and other countries, especially BRICS and neighbor countries.

To analyze the second plastic hinge of high bridge pier formed in the earthquake and study the pier seismic performance, this paper takes the Kunming Slope Railway Bridge as an example. The simulation model was built by the elastic-plastic finite element ANSYS software. The buckling load of piers was calculated by buckling analysis capabilities of ANSYS software, a small enough initial offset given to the model, then the buckling load of piers put into the model. The deformation of non-linear model under the loads was calculated, the process was recorded that the reinforced concrete bridge piers initially yielding on the cross-section, continuously rotating around the neutral axis, and finally forming the eventually plastic hinges in certain parts of pier. The location of the plastic hinges can be inferred by final data of analysis software. By analyzing the calculated results, the seismic performance of the second plastic hinge in high bridge is studied.

This paper presents a mathematical model to simulate the actuation of a multilayer metallic strip. The model computes the radius of curvature of the actuator when it curls because of difference in thermal coefficient of the different metals used in the strip. The mathematical model for simulating the radius of curvature is based on the earlier work by Timoshenko [4], and Jianyu Fu[5]. The radius of curvature computed is used to calculate the voltage to uncurl the actuator. Numerical experiments were performed on the model and the trends were found to be in agreement with the experimental data.

Impregnated paper for plywood formwork is an important material for the production of plywood formwork. It was developing with plywood formwork and the market had been expanding. Absorption and wet strength are main factors which can effects on the property of impregnated paper. In this paper, mechanical chemical pulp and waste paper were used to make special impregnated paper for formwork. The ratio of EMP, dosage of aid, and operation conditions were discussed. The result showed that the absorption was improved by increasing ratio of EMP, adding agent, drying quickly, and lighter pressure. A certain ratio of AOCC is necessary to ensure strength. The paper also discussed the difference of white spot between bamboo plywood formwork and plywood formwork which indicated that white spot caused by waste paper .However, it wasn’t damage the quality of structures.

Ball-end milling of Cr12MoV die steel was studied using ceramic and cemented carbide inserts under different cutting conditions. The cutting forces, wear patterns and chip patterns generated using the different cutting tools at the different cutting conditions were investigated using a three component piezoelectric dynamometer and VHX-600E large depth-of-view 3-D scanner. The relationships among the cutting forces, wear patterns and chip patterns were discussed. The results indicated that the cutting forces caused by the ceramic insert were slightly lower than those caused by the cemented carbide insert under the same cutting conditions. For ceramic inserts, effects of cutting conditions on the rake face wear were different from those on the flank wear. The higher wear for the ceramic insert was caused at the lower cutting conditions but the higher wear for the cemented carbide insert was encountered at the higher cutting conditions. The squeezed chip was involved with the higher cutting forces. The sharper cutting edge of the cemented carbide insert was responsible for chip patterns caused by the No. I cutting condition. The effects of cutting conditions on wear patterns were more evident than that on chip patterns.

This paper presents a general algorithm for topological optimization of the incompressible Navier-Stokes fluid flow based on a level set method. This is a direct extension of our previous work on Stokes flow of such problems. First we obtain the shape sensitivity analysis using the material derivative concept and adjoint variable technique, and then we couple the shape sensitivity analysis result into the level set function as the advection velocity. Since the level set method is implemented in an Euleran framework, the computational cost of the proposed algorithm is moderate. A Benchmark example is provided to illustrate the efficiency and validity of this method.

A characteristic radial basis meshless method (CRBM) is developed for numerically solving convection-dominated diffusion equations. This method is a truly meshless technique without mesh discretization, and it is numerically stable and more efficient than the characteristic finite element method (CFEM) as demonstrated by the provided numerical results for convection-dominated diffusion problems. Moreover, the existence and uniqueness of the solution to the method are proved.

LogicSQL is an object relational database management system implemented with the advanced (formula-lock based) concurrency control protocol, and the steged database architecture. It is independently developed based on the Linux high-level security database system. Ministry of Science and Technology "863" Database Group of the major projects comments LogicSQL database "It is the only hope that China’s database products will be able to contend with America’s mainstream database products in the next few years." Access control policies are security policies that govern access to resources. It can be applied to several new types of databases. In this paper, we discuss access control in multilevel database management systems applies and illustrate the main applies of security mechanisms in the LogicSQL database system.

An orthogonal test was carried out so as to analyze the cutting force in high speed rough milling with ball-end cutting tools. The wave form of the cutting force components was analyzed. The range analysis was performed to investigate the effect of cutting parameters on the cutting force. The analysis results show that the depth of cut and feed rate have the most significant effect on the resultant force. An empirical equation to describe the resultant cutting force was developed.

Corn stover is a largely feasible and cheap renewable resource with low commercial value. An attractive alternative is utilization of corn stover for chemical industry，medicine，biochemistry etc. However, the production costs are still too high to apply on commercialization. The purpose of this study was to use the response surface methodology (RSM) to optimize of cellulose salvation by ZnCl2 after the steam explosion .The solution of cellulose that had been pretreated with 87% ZnCl2 at 139 °C for 49 min resulted in an optimum solubility of 76.2%.

This article used the elastic-plastic finite element analysis method based on strength reduction theory and researched the regularity of longitudinal formation cracks during the loess tunnel construction. It analyzed the development trend of the crack dips and the distance between the surface crack and the tunnel center by different depth conditions when using the full section method and the bench cut method during the construction. From that it can get the boundary value of tunnel depth that the longitudinal crack can reach the ground. The result shows that: (1) Through the finite element analysis of the continuum structural model, it is feasible and effective to use the method, which is based on the area including the shear stress greater than the cohesive stress, the mutant horizontal displacement, and the change trend of the vertical displacement, to analyze the trend and the scope of longitudinal cracks after the excavation of the loess tunnels. (2) When using the full section method, the longitudinal cracks can reach the ground as long as the buried depth is less than 50m.With the increase of the buried depth, both of the depth of the cracks and the distance between the cracks and the tunnel center are all increased and the crack dips are changeable whose range is 56º~67º. However when the buried depth is more than 50m, the cracks can’t reach the ground and develop from the vault to the ground. The slip tendency near the ground is diminished. With the increase of the buried depth, the dips get larger, but the distance between the cracks and the tunnel center and the crack depth are invariable. (3) When using the-bench-cut method, the development trend of the formation crack is similar to that of the full section method. The cracks can reach the ground when the depth is less than 40m, and the range of the cracks is 56º~62º, or else the cracks can’t reach the ground. (4) From controlling the surface cracks, the bench cut method is superior to the full section method.

Tunnel drainage influence range is a difficult hydrological problem. It relates directly to tunnel groundwater environment influence degree in construction and operation stages. Based on Shibanshan tunnel in Shijiazhuang-Taiyuan passenger line, this paper analyses influencing factor of tunnel drainage influence radius and flow transient process adopting heterogeneity and anisotropy equivalent flow models. This paper studies the tunnel drainage influence radius and construction progress , hydrology factors, geological factors and rainfall infiltration factors relations. Research results show that the influence factors are rock permeability, rainfall infiltration recharge and aquifer thickness on tunnel top, less influence factors are structure surface direction, anisotropy characteristic coefficient and primary support of the closed time. The conclusions will provide technical supports for evaluating the tunnel construction of groundwater environmental impact.

We have done a survey about the surface crack of the loess tunnel of Zheng-xi passenger railway by field survey, geophysical exploration test and pit detection and also have researched the produced regularity of the surface crack of the loess tunnel, especially about in the depth. The result of the survey and the detection indicates that: (1)The surface crack is mostly visible in the shallow area of the loess tunnel entrance. The visible width of the surface is extensive (0.2~200mm) and it is mostly visible in the tunnel, the depth of which is below 60m. The visible or wide cracks mostly appear in the area whose surface settlement is above 80mm. The width of the surface crack of the tunnel, which has a more shallow depth and a larger settlement, is much wider. (2)The effect of the High-density electrical method reflecting the development of the surface crack is obvious. The method of seismic reflection wave and seismic imaging is more accurate than Rayleigh wave in interpreting depth development of the crack. (3)There are two kinds of performance of the surface crack: longitudinal crack that inclines to the inside on both side of the tunnel and circumferential crack perpendicular to the axis of the tunnel. (4)The visible crack depth of the surface crack is limited, which is about 3.0~10m and it always doesn't reach the top of the tunnel. The depth by the geophysical exploration test is much more depth, which is about 10~15m.

In this study, we restrict our attention to shape optimization of a body immersed in the Navier-Stokes fluid flow. The formulation and numerical results of the proposed method are presented. The proposed method is based on an optimal control theory. The optimal state is defined by the reduction of drag forces subjected to the immersed object. The cost functional should be minimized is governed by the Navier-Stokes equations. The shape sensitivity analysis of the cost functional was derived based on the adjoint method. Finally, a numerical example is given to show the feasible for the proposed algorithm.

Superabsorbent polymers are lightly crosslinked, hydrophilic polymer network having many functional groups. The adsorption properties in heavy metal ion solutions using poly(acrylate-co-acrylamide)(PAAM) are investigated. It is found that PAAM has a high uptake to heavy metal ions, and that the adsorption of heavy metal ions is greatly influenced by pH and the initial solution concentrations. The biggest and the smallest amount of adsorption are Cu2+and Cr3+in CuCl2and CrCl3solution, respectively. It was feasible for selective adsorption of the metal ions in the solution onto PAAM hydrogel by controlling the pH values of the mixing solution for CuCl2, FeCl3, CrCl3.Langmiur equatiom can satisfactorily fit for the adsorption of Cu2+while not fit for that of Fe3+and Cr3+.

There are many factors influencing the bearing capacity of spatial joint, whose load-carrying capacity is also more complicated. In this paper, the finite element method is adopted for the tubular joint of TX-type square steel tube to explore the influences on the ultimate bearing capacity resulting from the axial stress of main tube and the loading ratio JAA. The analytical results show that: for the joint with small β, the pressure of main tube will reduce the joint strength, while the appropriate tension is beneficial, but too large tension will lower the joint strength. The loading ratio JAA has significant influences on the joint, and when the ratio is positive, the outer-planar branch plays a very good role in the stiffening effect of the joint.

The milling experiments of the annealed T10A steel were carried out in the various cutting conditions using the coated cemented carbide tool. The cutting parameters were designed by the multi-factor orthogonal experiment method, and the effects of cutting speed, feed, axial depth of cut and radial depth of cut on the cutting force and tool wear were investigated. The tool wear mechanisms were also discussed. Adhesion, abrasion, diffusion and oxidation were the main tool wear mechanisms. According to these investigations, the optimizing cutting parameter was recommended.

With the help of enterprise information technology wave, a lot of internal information resources have come out. Enterprise search achieves more accurate positioning information, and it realizes the value from the information across to the knowledge. This paper discussed the enterprise search systems based on database security services. Such as Oracle Ultra Search, Sybase Enterprise Portal and LogicSQL-based enterprise archive and search system. The enterprise information resources integration and security search are completed in the search system.

Access control is the process of mediating every request to data and services maintained by a system and determining whether the request should be granted or denied. Access control policies are security policies that govern access to resources. It can be applied to several new types of databases. LogicSQL is an object relational database management system implemented with the advanced (formula-lock based) concurrency control protocol, and the steged database architecture. In this paper, we discuss access control in multilevel database management systems applies and illustrate the main applies of access control in the LogicSQL database system.

Kaolin/sodium lignosulfonate graft acrylic acid and acrylamide superabsorbents composites(LPAAM) were prepared by solution polymerization using sodium lignosulfonate, acrylic acid and acrylamide as raw materials, kaolin as inorganic filler, potassium peroxydisulfate as initiator, N,N’-methylene-bis-acrylamide as crosslinker and by saponifying 2h under 90 , 0.10mol/L NaOH solution. Its equilibrium absorbencies in distilled water and 0.9%NaCl solution are 1003g/g and 89g/g, respectively. The structure, morphology and thermal property are testing by FTIR, SEM and TG, respectively.

Hot simulation tests at different deformation technology parameters were carried out for a microalloyed high strength steel produced by CSP hot rolling and the stress-strain curves during deformation were measured. Based on the experimental results and the discussions of present flow stress models, a new flow stress model incorporating interactional effect of deformation temperature, strain and strain rate on flow stress was developed in the paper. Excellent agreement between measured and predicted flow stress values is obtained for new flow stress model of a microalloyed high strength steel rolled by CSP. In addition, the comparisons of flow stress prediction errors between several models and one given in the paper reveal that the prediction accuracy of new flow stress model presented in the paper is higher than other models.