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BEE project is a category of complicated and systematic engineering in construction industry, not only concerned with alleviation of energy shortage pressure and melioration of residential conditions, but also related to both sustainable development of low carbon society and promotion of circular economy. Three main parts including green building, renewable and clean energy technologies and environmental protection are analyzed and studied in a holistic way. In general, energy-saving technologies and energy management pattern have been researched in detail based on general building energy efficiency theory, so as to effectively promote building energy-efficient application system.

Concerning the defect of fuzzy membership as a function of distance between the point and its class center in feature space for some current Fuzzy Support Vector Machines (FSVM), a new FSVM based on entropy and Genetic Algorithm (GA) named EGFSVM was proposed in this paper. Making use of evaluation of entropy and intelligence of GA, EGFSVM enhances the classification capability and makes clustering center more suitable and membership more accurate. Experimental results show EGFSVM has better precision and classification performance, especially to multi-class and large scale data.

EMU gearbox is a key component of high-speed train, the reliability of the gearbox will directly affect the operational safety of EMU. The box of EMU gearbox is with light alloy materials, bearing structure, so the box is subjected to greater loads and shock and vibration. Designers most take into account the static strength and stiffness of the box, ignore the fatigue failure. Fatigue failure is the leading cause of mechanical structural failure, while the peak load cycle fatigue failure is often far less than estimated in accordance with the static fracture analysis "safe" load, so the EMU gearbox box’s fatigue analysis is needed. Combining high-speed EMU gearbox actual operating conditions, using finite element method to do fatigue analysis of the gearbox box while the analysis result is evaluated and amended by the Smith schematic analysis method.

An epipolar line constraint equation for robotic binocolar stereovision (BSV) is first established for the measurement and reconstruction of workpiece surface, in which the intrinsic parameters of two cameras and their extrinsic structural parameters with respect to a robotic reference base are included. To determine a sole matching point between left and right images, a laser emmiter is added to BSV to form a stripe on workpiece surface, experimental results show that the measurement accuracy of 3-dimensional (3-D) workpiece surface can be improved by combining epipolar line constraint with laser stripe projection, and the 3-D workpiece surface can be reconstructed with less errors.

The effects of silica fume (SF) on compressive strength of concrete have been analyzed. The compressive strength results of concrete mixed over different water–binder ratios as well as different replacing percentages of SF were analyzed. The results of the experiments showed that when the polymer/binder materials ratio increases, the compressive strength of concrete decreases. A mathematical model has been proposed for evaluating the strength of concrete containing SF. The proposed model provides a probability to analyze compressive strength based on the time of curing in water (t), water to binder materials ratios and SF to binder materials ratios which are shown as (w/b) and (s). This model might serve as a useful guide for increasing concrete compressive strength.

In order to find out the real treatment efficacy of common used formaldehyde-removal product. Comparison study was conducted at different reaction time and dosages in 5L glass-made device using photocatalyst, active carbon and chlorine dioxide, respectively. The results showed that all the three methods can remove formaldehyde effectively. Photocatalyst and chlorine dioxide react with formaldehyde more quickly. As to 1.0 mg/m3formaldehyde, using more than 0.3mL photocatalyst or 30mg/L chlorine dioxide for 30min is suitable, while 2mg/L and 18h is needed by active carbon.

Visible Light Communication (VLC) technology is one of the main candidate solutions for Intelligent Transportation Systems (ITS). This paper presents a comprehensive study on VLC based anti-rear-end collision scheme on the highway. A detailed VLC based rear-end collision avoidance model is proposed with theoretical analysis and numerical simulations.

In order to analyze the explosion characteristics on the free field performance of thermobaric explosive, parameters of blast waves produced by the investigated charges in an open space were measured by the use of piezoelectric sensors and the results were compared to traditional TNT. Moreover, a numerical simulation of TBE explosion in free field was performed within the frame of AUTODYN. Comparison with TNT reveals that the values of peak pressure and impulse of TBE are higher than that of TNT due to the secondary reaction of Al and detonation products. It is found that the simulation results of TBE detonation blast wave parameters coincided very well with the experiment data. This demonstrates that the simulation method used is an effective way to depict the spreading of detonation waves in free field for TBE.

Effects of La content on the infrared stealth of ZnO: (La, Al) coated cotton fabrics were studied through XRD, SEM, ICP, IR_2 dual-band emissivity measuring instrument and the infrared camera instrument, where the content of Al remained unchanged. It was suggested the doping of Al and La was favorable for providing more free electrons, improving scattering of infrared photon, and decreasing the infrared emissivity of ZnO: (La, Al) coated fabric in the range of 8-14μm wavelengths. Thermography indicated that ZnO: (La, Al) coated fabric gave as low thermal radiation as the environment.

Let {Xnk,n≥1,k≥1} be a ρ--mixing random sequence, by using the moment inequality and truncation method, we studied the weak convergence of random sums for ρ--mixing random sequence, which extended and improved some results in related literature.

In order to effectively analyze the mechanism for the occurrence of ship collision accidents caused by human factors, an accident causing chain was constructed using the Bayesian network structure and the data mining algorithm. According to navigator's cognitive behavior forming process and human errors, the accident cause network structure was constructed using the Bayesian network structure by analyzing 120 typical cases about ship collision accidents caused by human factors; a collision accident cause chain was obtained by mining the frequent combination of human errors using data-mining based Apriori algorithm and JAVA programming language.

ZnS/TiO2/Chitosan nanocomposite thin films were prepared by entrapping zinc ions and nanosized TiO2 in chitosan films under mild conditions. The surface structure and morphology of the film were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Methyl Orange was selected to evaluate the photocatalytic activity under simulated solar irradiation. The HRTEM results show that TiO2 and ZnS were dispersed uniformly with diameters of 20–30 nm. The prepared film exhibits high photocatalytic activities. About 93.5% Methyl Orange(3.6×10-5 mol/L) were photodegraded by 0.6 g L−1 photocatalyst at pH 4.0 with 120 min irradiation. The influence of the reaction pH, stability and reusability of the film have also been investigated. It can be developed as a economically feasible and environmentally friendly photocatalyst for the practical industrial waste water treatment.

The bonded joints between carbon fiber reinforced polymer (CFRP) and high strength concrete subjected to different freeze-thaw cycles were studied and the results were analyzed. The test results indicate that with the increase of freeze-thaw cycles, effective bond length, ultimate bond load and ultimate global slip response will decrease. But it has little effects on initial stripping load. The failure modes change from adhesive debonding to shear failure of concrete.

When we design a routing protocol for WSNs, it is necessary to found an energy control mechanism to reduce the overhead of wireless communications. Considered that WSN systems need a simple routing protocol in practical applications, we designed a simple Energy-hops-based routing protocol (SERP) in this paper which can be used in most WSN systems with low communication overhead and complexity. We analyzed the performance of the SERP, furthermore we run it in a real WSN experimental system consist by GAINS3 sensor nodes. The experiment result confirmed that the SERP is highly effective by which the WSN system energy can be balance while the working lifetime can be increased.

SEM and Automated Surface Area & Pore Size Analyzer were used to characterize surface morphology and specific surface area and the pore size distribution of fibers. The results showed that specific surface area and pore size distribution increase after ultrasonication. The ash content of the composites of ultrasonic treated fiber is larger than the untreated fiber, and the magnetic properties show a good superparamagnetic behavior.

An externally pre-stressed continuous box girder bridge model is designed according to loading features of the continuous beam. The CFRP bars and steel strands are used to make two models for externally pre-stressed reinforcements Analysis of the two models under three different load stiffness and loss of prestress, through calculation and analysis, found that two kinds of prestressed concrete material model under three load deflection basic same, also almost the same change trend, prestressed RMS model than model 1, 2 but with the increase of load model 2 prestress loss is big. Analysis results of CFRP materials and application to provide the reference in the bridge.

According to the current technological deficiency of license plate recognition, this paper uses digital graphic processing technique and BP Neural Network algorithm fusion to achieve automatic recognition of license plate. Input the image settled in the previous period in the trained BP neural network to obtain the final license plate character through simulation. The validity and feasibility of the algorithm can be verified through the simulation experiment of standard license plate image.

With the rapid development of Internet and the network information resources can be Shared height, information system security face severe challenges. Firstly, this article from the current status of the network security, combined the new changes of the network security situation, getting the conclusion that the use of the necessity of intrusion detection system. And then it made a comprehensive overview on network security model put forward that was to achieve the purpose of security, which need to establish a reasonable network security model. By introducing the common types of network intrusion and network security technology, it lead to an intrusion detection system, and the concept of intrusion detection system, system structure and detection methods in detail in this paper.

Based on well-balanced Roe’s approximate Riemann solver, a numerical model is developed for the unsteady, two-dimensional, shallow water flow with variable topographies. In this model, an efficient methods are applied to treat the source terms and to satisfy the compatibility condition on unstructured grids. In the method, different components of the bed slope source term are considered separately and the compatible discretization of the components is presented. The newly developed model is verified against analytical solutions and measured date, with good agreement.

Due to lack of considering the non-geometric process parameters during assembly process planning, it is difficult to control the production cycle, cost, quality, reliability, stability and consistency of high-performance mechanical systems. To change this situation, a prototype software is developed by taking into account the non-geometric process parameters. Based on the alignment information, this paper concentrates on the data modeling of the system. With the system, the manufacturing process can achieve the assembly materials management, assembly process planning, alignment process monitoring, alignment data collection and statistical analysis. After analyzing the process data, design parameters will be refined and assembly performance will be optimized.

The amphiphilic chitosan oligosaccharides graft copolymer (PHCSO-g-PCL) was synthesized via ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) through an amino group protection route using phthaloyl chitosan oligosaccharide (PHCSO) as intermediate. The graft reaction was carried out in Pyridine at 120 °C with a chitosan oligosaccharide (CSO) initiator and a tin 2-ethylhexanoate (Sn (Oct)2) catalyst. The amphiphilic PHCSO-g-PCL nanoparticles were prepared through the self-assembled in DMF organic solvents. PHCSO-PCL copolymer was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The physicochemical properties of the hydrophobized PHCSO-g-PCL nanoparticles were investigated by using dynamic light scattering (DLS). The results of DLS showed that the hydrodynamic diameters and particle size distribution with various concentrations of PHCSO-g-PCL nanoparticles were from 69.82 nm to 195.9 nm with a narrow polydispersity factor of 0.212 to 0.172.

Electro-hydraulic servo valve is the key component in electro-hydraulic servo control system, it has high reliable assemblies over a long period of time. This paper utilizes the accelerated degradation testing to evaluate their reliability and life. Firstly, the wear failure mechanism of electro-hydraulic servo valve is analyzed to determine. Then, by modeling the degradation process as a drift Brown Motion, this paper generated the reliability model of the electro-hydraulic servo valve. Finally, the maximum likelihood is used to estimate the degradation data of leakage from the test. The methodology in this paper is demonstrated and validated by reasonability of estimation of electro-hydraulic servo valve.

This paper studied the control strategy of single-phase two-stage grid-connected photovoltaic generation system. The two-stage topology includes the boost converter and single phase inverter. The function of maximum power point tracking (MPPT) is achieved in the boost circuit by IC (Increment Conductance) method. The inverter circuit adopted the double-closed loop control, a DC voltage outer loop control for power balance with PI correction and an AC current inner loop control for feedback designed to ensure the current quality and stabilize the DC voltage. The inner loop used the novel quasi-Proportional-Resonant (PR) controller, which has a better steady tracking characteristics and stronger anti-interference ability to the disturbance. Finally, a simulation system is built with Matlab/Simulink in this paper to verify the validity of the MPPT algorithm and the quasi-PR control strategy.Keywords：Photovoltaic Generation System;Maximum Power Point Tracking; Grid-connected Inverter; quasi-Proportional-Resonant (PR) controller

Micro-pore characteristics and its control factors are analyzed according to mercury penetration, physical property parameters, flake observation and scanning electron microscopy, etc. Studies show that Chang81 reservoir is ultra-low permeability, its main pore types are intergranular pore and feldspar dissolved pore, its main pore throat types are low porosity, fine throat to micro-fine throat. Diagenesis stage of Chang 81 reservoir is situated in the diagenetic stage B. compaction mainly reduce the pore space, while the micro-cracks caused by compaction can be good reservoir space; ferrocalcite cement, Chlorite coating and kaolinite would destroy the reservoir space by filling in the primary pores and secondary pores; hydration of feldspar would destroy the reservoir space, while dissolution of feldspar would improve the reservoir space; dissolution of feldspar is the most favorable diagenesis.

It discusses two simplified elevator bearing beam models that describe the design installation way usually and the on-site installation way respectively for the elevator’s traction machine. Taking a real 12-ton traction elevator as an example, it analyzed the load force on the bearing beam, and also used finite element analysis software ANSYS12.0 to calculate their stress situation of two simplified models. Then it compares the bearing beam strength and stiffness influences based on two different fixed ways. Finally, it suggested a conductive advice to make more reasonable choice to install the bearing beam for elevator safety.

This paper selected the double nozzle flapper type electro-hydraulic servo valve as the research object. Through to analys the wear failure mechanism of electro-hydraulic servo valve to determine the test stress and to select the Pressure gain and leakage as the Degradation performance indicators. So it makes the detail Accelerated degradation test project . and it designs a test system for the pollution wear test. Then, by modeling the degradation process as a drift Brown Motion of which the first passage time follow inverse Gaussian distribution, this paper generated the reliability model of the electro-hydraulic servo valve. Finally, the maximum likelihood combined with least square of accelerated degradation testing data is used to estimate the degradation data of leakage from the test.

With changing strong nonlinear Duffing equation subject to harmonic excitation with damping in complex number field as an object, the amplitude frequency response equation of primary resonance of the system is obtained through parametric transformation with application of MLP method and modified method of multiple scales. In different approximation solution forms and different time scales, the two methods lead to the same amplitude frequency response equation. Thus, the two methods are mutually verifiable. Numerical analysis shows that for the strong nonlinear Duffing equation with damping in complex number field, the nonlinear stiffness coefficient is more than zero and the amplitude frequency response curve of primary resonance leans to the left, which is different from the weak nonlinear Duffing equation.Chinese books catalog: O321

In this study, a kind of uncertain network design problem, network design problem under uncertain construction cost, is researched.The discrete network design problem under uncertain construction costs deals with the selection of links to be added to the existing network, so as to minimize the total travel costs in the network. It is assumed that the value of the demand between each pair of origin and destination is a constant and the construction costs of each potential link addition follow a certain stochastic distribution. In this paper, a bi-level and stochastic programming model for the discrete network design problem is proposed. The construction costs of potential links are assumed as random variables and mutually independent with each other in this model. The upper-level model is a chance constrain model with the objective function of minimizing the total travel costs in the network, and the lower-level model is a user equilibrium model. The stochastic model is then transformed into a deterministic one. A branch-and-bound solution algorithm is designed to solve the deterministic model in an efficient way. At last, a computational experiment is conducted to illustrate the effectiveness and efficiency of the approach proposed in this paper. The results show that the stochastic model is more flexible and practical compared with the deterministic one.

The berth and quay crane in port are scarce resources. The scheduling optimization of them affects the ship's operating costs directly. In this paper we build an integration optimization model of berth allocation and quay crane scheduling to minimize the operating costs of quay crane and operating costs of the ships. A new genetic and ant colony algorithm is designed to solve this model.

Light steel houses are widely applied to low-rise industrial buildings for lightweight, easy industrialization and fast construction. But under the condition of strong wind, there often occurs wind-induced damages to light steel houses because they are sensitive to wind loads, causing huge economic losses. This paper offers a wind-resistant design for a steel structure warehouse which may suffer from force-14 super typhoon with maximum wind speed of 150 km/h. The main factors affecting the wind-resistant capacity of steel structure plants as well as the attacking characteristics and failure mechanism of typhoon on low-rise buildings are fully analyzed. Opinions on the design of low-rise steel structure warehouses against typhoon have been proposed by discussing different wind directions. Considering conceptual design, we also provide some concrete measures of wind-resistance for low-rise buildings in coast areas.

In this paper, by the moment inequality of generalized pairwise negatively quadrant dependent (NQD) sequences, we prove the convergence of the generalized pairwise NQD sequences, which extend and improve the previous relevant results.

A rapid template matching algorithm is used to locate l-emitting d (LED) die array on wafer planes in vision-based LED sorting or die-bonding system, the image of LED die array is first converted to binary image and is pre-processed through morphological operations such as dilation and erosion, and the cross correlation operation between LED die templatae and wafer image in frequency domain is implemented by using fast Fourier transform (FFT), and the pixel coordinates of all LED dies on the wafer plane can be determined at one time using the cross correlation in frequency domain (CCFD) instead of in spacial domain. Experimental results of LED die array measurement to a large-diameter LED wafer show that detection efficiency is far higher than conventional normalized cross-correlation (NCC) algorithm, and is only half of consumed time to compare with the sequential similarity detection algorithm (SSDA), the proposed CCFD algorithm can be used for rapid LED die array location in vision-baesd LED sorting or die-bonding machines.

As an important performance parameter of nitrile-butadiene rubber（NBR）sealing ring, the compression set is a main factor influencing rubber's life. Using the compression set amount as its degradation measurement and the temperature as accelerating stress, we perform the design and actual implementation of a set of accelerated degradation test of NBR considering step-stress. Then we evaluate the results using accelerated degradation model based on the drift theory of Brownian motion. Finally we get the estimation of reliable life of sealing ring under normal temperature. The research in this paper can also offer a new method for the application reliability and life evaluation of rubber products.

The aerodynamic heating and infrared radiation characteristics of BrahMos supersonic cruise missile were investigated. The aerodynamic heating was simulated using finite volume method, and the infrared radiation characteristics were simulated by reverse Monte Carlo method. Infrared radiation characteristics of missile surface were analyzed in different surface emissivity and flight altitudes, and the effects of environmental radiation and atmospheric attenuation were considered. The results show 8~14μm and 3~5μm environment radiation were approximately 10% and 2.4% of total radiation respectively, when the surface emissivity is 0.3. The proportion of environmental radiation reduces nearly half when the surface emissivity increases by 0.2.

The necessity of integration of design and manufacturability was analyzed. By carrying out the research of mechanical product digital structure design and manufacturability analysis and evaluation integration technology, the roadmap of design manufacturability integration was established with support tool integration, information integration, knowledge integration, function integration and flow integration. The design manufacturability integration support system was developed. It was supported that designers could carry out manufacturability analysis and evaluation while doing structure design and finally the changes and rework of mechanical product design was reduced and the success rate of digital structure design was improved by using the system.

A 2 D CFD model was established to simulate sawdust gasification in an entrained flow gasifier using Ansys Fluent software. Syngas composition, syngas yield and syngas LHV were evaluated. The simulated syngas compositions were in agreement with the experiment results. The relative errors of syngas yield and LHV varied in the ranges of 2-15% and 1-9%, respectively. The results showed that the numerical model established in this study can be applied to simulate biomass gasification in entrained flow gasifier.

The present studies of assembly accuracy predicting for complex products are mainly oriented to the early design stage. The final product assembly accuracy is computed using a variation propagation model, which is constructed based on design tolerance model and assembly model. Generally, the solving results are quite different with the actual values. In this paper, the axis angular variation calculation of the spacecraft cabin at the assembly phase was studied. And a novel analysis method for assembly variation was proposed with the consideration of measurement uncertainty of the key characteristics. An example was studied to illustrate and demonstrate the feasibility of the proposed method.

A fast and accurate infrared radiation calculation method was investigated. Reverse Monte Carlo (RMC) method was adopted to calculate the Infrared (IR) Radiation characteristic of surface. The computational code used Mersenne Twister (MT) method to generate random number, and bounding box method to accelerate computational speed. The Infrared Radiation characteristics of some typical geometric structures were calculated and verified. The effects of emission photons number and mesh number on calculation results were analyzed. The results show the error between calculation value and theoretical value is less than 0.02%. The calculation time is proportional to emission photons number and mesh number.

In order to analyze temperature field and stress field of Co-based alloys laser cladding, the model of Co-based alloys laser cladding with preset-powder method has been made on low carbon steel substrate. The temperature field and stress field of laser cladding process was analyzed by SYSWELD software, and Experimental verification is done. The results showed that temperature field is appear to a trailing tail of comet, favorable metallurgy bonding with 12.3% dilution was obtained by scanning velocity was 4 mm/s. and instantaneous cooling rate of molten pool with 4 mm/s and 5 mm/s are increased to 1.47 times and 2.02 times of 3 mm/s. The transverse residual stress different nodes on the surface of coatings are always tensile stress, and it is almost steady, the maximum deformation is 0.34 mm at the edge of work-piece, these are consistent with experimental results. These results provide reference and guide to obtain high quality coatings.

A robust method based on dual back-propagation neural networks (BPNN) is proposed to recognize light-emitting diode (LED) dies on wafer planes in vision-based LED sorting system. To improve the recognition accuracy of LED dies, particularly under the condition of LED die image degradation, a dual BPNN with 3 layers architecture is first constructed, in which the two BPNNs are trained respectively using the region features and edge features of die images based on batch gradient descent method, and then the outputs of the dual BPNN are fused according to Dempster-Shafer (D-S) theory to generate a final decision. Applying the trained dual BPNN as a classifier, the recognition experiment of a large-diameter LED wafer is completed, experimental results show that LED die recognition accuracy of the dual BPNN is higher than that of the single BPNN based on the region feature or edge feature and is robust to die image degradation, it can be used for LED die array location in vision-baesd LED sorting machines.

In order to reduce the wear of pantograph and catenary, prolong working time of the friction pair, and ensure the quality of current collection, a new type of pantograph active control strategy is designed. The strategy is based on the theory of friction and wears with electric current, control theory and micro-control technology, and is characterized by the dynamic wear test of catenary and the contact force control. The results show that the wear of the pantograph and catenary can be significantly reduced, the contact force fluctuation also can be effectively controlled, and the quality of the current collection of pantograph-catenary can be improved, while the active control strategy is applied.

Through simulating box girder with shell element, the influence of the top flangebottom flange and web thickness on the shear lag effect of box girder used in cable-stayed bridge was discussed on the background of Jianning bridge in Zhuzhou. Parameter analysis of the thickness change of the top flange, bottom flange and web on shear lag effect of box girder was based on analyzing and comparing the calculated results. The results show that the thickness change of the top flange, bottom flange and web have more influence on the shear lag effect of top flange than that of bottom flange; thickness increase of bottom flange and web can make the shear lag effect intensified obviously; and thickness change of web has the most significant influence on the shear lag effect among them for box girder with single box and three rooms used in cable-stayed bridges.

The Wireless sensor networks (WSNs) are rising research domain relate to several subjects and applications which consist of a large number of sensor nodes. Because of the universality of sensor network technology, it is difficult to teach students. To analyze pivotal technologies and didactical specialties and has explored functions, the system structure and experiments of sensor network synthetically laboratory. In the end, the article has given an example to illustrate the actuality and the tendency of sensor network synthetically laboratory.

Development of slope disintegration is close to soil mechanic characteristics such as shear strength indices. Soil grain diameter and water content were tested. Soil direct shear test was conducted to analyze the relationship between shear strength indices and the influencing factors. The experimental data indicate that clay content and the range affect soil cohesion value and the scope. Soil cohesion increases with bulk density before 1.6g/cm3. But it decreases when the bulk after that. The results could provide a scientific basis for control of slope disintegration.

In recent years, people have been paying increasingly attention on monitoring the quality of drinking water, which becomes rather necessary after natural disasters such as the Beijing 7.21 rainstorm, considering that the drinking water is one of the main medium for epidemic spreading. Most of the existing evaluation methods have their bases on concise mathematical models, which often fail to describe the complex essential nonlinear relations between the water quality and the chemical material in it. In this paper, we propose the evaluation method by using the SOM neural network, a unsupervised method that is able to classify, and therefore evaluate, given water samples. In order to promote the convergence rate and the precision of SOM neural network when dealing with high dimensional and highly correlated samples, we add a PCA preprocessing procedure. Experiment results demonstrate that the improved SOM neural network could evaluate the water quality with high precision.

In order to analyze temperature field of Co-based alloys laser cladding, the model of Co-based alloys laser cladding with preset-powder method has been made by finite element method. The temperature field of coatings was analyzed by SYSWELD software, and Experimental verification is done. The results showed that temperature field changed from non-steady-state to steady-state in the laser cladding process. Favorable metallurgy bonding with 8.26% dilution was obtained by scanning velocity was 5 mm/s, the temperature gradient of surface coatings is obviously decreased to 1/20 of bonding interface, the solidification rate of surface is nearly 70 times of bonding interface. Right power with 1.6 kW and 1.87 kW was found when scanning velocity was 3 mm/s and 4 mm/s by SYSWELD software. Based on solidification theory, shape factor of crystallization are analyzed, these are consistent with experimental results. These results provide reference and guide for parametric optimization and control dilution rate of laser cladding. Key words: Laser cladding, Co-based alloy, SYSWELD, Simulation

According to the existence of uncertainty in the subway risk identification, introduced rule-based expert system technology, integrated expertise into the knowledge base, automatically identified construction parameters based on CAD drawings, discussed and designed automatic subway security risk identification expert system based on confidence factor theory. And taken underflow sand pit in subway station construction as an example, elaborated the key issues in the knowledge base construction in details, such as risk mechanism analysis, fact base structuring and rule base structuring. And proposed to combine the contribution (C(eij)) with fact credibility ( F(eij)) to confirm the evidence credibility CF(eij) =C(eij) × F(eij), solving the credibility assignment conflict when the fact of certainty and uncertainty existed simultaneously; Selected the threshold of risk conclusions credibility in representative conditions as the sub-boundary for risk potential classification, avoiding the risk omission problem. In this way, the application of expert intelligent decision technology was broadened in subway construction.

The paper presented, aimed at addressing hospital ophthalmic beds arranged unreasonable, integrated use of the analytic hierarchy process, fuzzy mathematical analysis, queuing theory, priority function, dynamic analysis mathematical analysis methods, and provide a package to improve hospital beds use efficiency, reduce patient surgery waiting time, predict a patient's hospital stay, and enhance the effectiveness of the management of hospital beds mathematical model to solve the reasonable arrangements beds.

This paper is basic on a new production small-scale mining road header. It researches the characters of the hydraulic system and mainly concerns on its constant power systems mathematical models, analysis of stability of working condition, the simulation and modulation using the software of AMESim.

The wide band antenna is a key technique for the passive radar. This paper proposed a new kind of wide band antenna combined with the Archimedean spiral and hemispherical helix for passive radar application. For the new antenna, the planar Archimedean spiral is mounted on the top of the hemispherical helix, and it is fed at the center of the Archimedean spiral. An antenna with specific structure and parameters was designed and simulated to obtain its radiation performances over the operating frequency range from 2GHz to 10GHz. For entire operating frequency range, the simulated gain is greater than 5 dBi and the voltage standing wave ratio (VSWR) is less than 2 when the characteristic impedance of transmission line at the terminal is 240Ω. Wide beam and approximately circular polarization characteristics are also observed. The simulation results demonstrate that the new kind of antenna has wide band radiation performances, which can be used in passive radars. Furthermore, the proposed antenna has simple structure and low cost, so it is suitable for mass fabrication.