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As an effective approach to confine fire-induced smoke transportation, the application of air curtains is introduced in high-rise buildings during fire. A series of computational fluid dynamics (CFD) simulations were carried out for a full scale corridor in high-rise building, in which different factors such as air curtain discharge velocity (ACDV), human evacuation and pressure difference are considered. The results show that with the ACDV increasing, the smoke flowing resistance of air curtain is greater. The factor of evacuation cause significant impact on the efficiency of air curtain. Compared with the pressure difference caused by wind effect, the fire effect would lead to higher critical pressure difference and discharge coefficient.

Centrifugal compressor in bootstrap turbine cooler was studied to build computational model of flow domain for compressor component. The relationship between pressure ratio πc, efficiency ηc, flow rate G and rotational speed N was calculated by 3D numerical method. Experimental data were compared with the calculated results and good agreement was achieved. It indicated that performance characteristics of centrifugal compressor under off-Design condition could be predicted by computational fluid dynamics (CFD) technology. Furthermore, internal flow characteristics and load distribution could be visualized directly by CFD post processing graph.

While the LLC regulator configuration presents advantages such as resonant soft switching and transformer built-in resonant elements, it does have the disadvantage of poor light-load efficiency due to higher switching frequency operation under such a condition. Using the GaN-Si FET cascode switches significantly improves the situation. Experimental results are also presented.

This article, according to engineering geological exploration and mapping data of landslides, describes the characteristics of the typical landslide in eastern Menyuan Basin, including the main landslide body, the surface of rupture and the base of the landslide. And then, through applying GEO-SLOPE finite element software, the evolvement process is analyzed by simulating the formation of dynamics mechanism.

In the area of grinding, ordering the abrasive gains is one of the key ways to improve the grinding wheel performance. In this article, the experimental investigations on the grinding temperature were carried out including using the superhard abrasive grinding wheel with phyllotactic, matrix, dislocation and disordered configuration, the temperature distribution of the grinding workpiece surface and the effects of grinding parameters on the temperature of workpiece surface have been obtained. The experimental results showed that the grinding temperature can be reduced efficiently by choicing the grinding wheel with abrasive phyllotactic pattern.

In order to obtain the effects of abrasive configurations on the grinding force of superhard abrasive grinding wheel, an experiment was carried out, which grinds steel material by the use of electroplating CBN grinding wheel with different abrasive configurations, mainly including disordered, phyllotactic, matrix and dislocation configurations. The results show that under the experiment conditions, the grinding force of each grinding wheel will increase with the grinding parameters, the grinding force is smaller by the grinding wheel with orderly configurations than disordered configurations and under the same condition of experiment, the grinding force is smallest by the grinding wheel with abrasive phyllotactic configurations.

In order to improve the performance of end face grinding wheel, the phyllotaxis theory is introduced into the design of the wheel. Meanwhile the movement track equation of the end grinding is established, and the effects of the phyllotactic coefficient on the grinding surface roughness are studied. The simulation results show that the lower surface roughness values can be obtained when choosing reasonable phyllotactic coefficient. It will provide theoretical basis for the ordered abrasive patterns of the end grinding wheel.

Aging characteristics and triggering mechanisms of geological disasters were analyzed to clarify the characteristics of geological disasters in loess areas, develop a geological disaster risk assessment system, and improve risk management of geological disaster. Risk periods of geological disaster were classified on the basis of disaster type, and a time-space coupling mechanism was applied to manage geological disasters dynamically. The risk period analysis was applied to risk assessment of geological disaster in Yaozhou District, Tongchuan City, Shaanxi Province. The risk period analysis may add a new element and promote improvements to practical applications of risk assessment system of geological disaster. According to this research results, new requirements for long-term supervision of farming activities and recommendations for an approval system for construction projects are suggested. In addition, geological disaster insurance product development is proposed.

In order to get the convex surface with phyllotactic pattern, the convex surface with phyllotactic pattern on end face of work-piece and its mask were designed based on the phyllotactic theory of biology, the surface was fabricated by electrolytic etching method, and also the fabricating processes were investigated .The results show that the convex surface with phyllotactic pattern can be fabricated by electrolytic etching method , and under the condition of room temperature (25°C), composite etching liquid which composed of NaCl,NaNO3,Na3PO4,etc., has better performance than the pure NaCl etching fluid, and in the current density of 15A/dm2, the etching rate was 3.292μm/min by composite etching liquid when steel 45 is etched. This technology can be used for fabricating the end grinding wheel with the phyllotactic pattern of abrasive clusters.

The campus network is to provide broadband multimedia network teaching,scientific research and comprehensive information service for teachers and students. With the popularization of campus network and function of continuous improvement,to the campus network security threats are also more and more,through the core switch in campus network by using various safety strategies,including NAT,VLAN,Access-List,effectively guarantee the safety of the campus network.

This paper establish a firing data calculation algorithm for the novel anti personnel / anti materiel multipurpose projectile (APAM), and the simulation results demonstrate the validity of the algorithm. The algorithm highly compatible with tank. The algorithm has very fast calculation speed, low requirement for hardware. The algorithm is helpful to improve the firing rate of the tank, reduce the equipment cost of new ammunition system.

By analyzing the component population and the requirements in the standards, we proposed sampling plan for project site. We can gain the lot acceptance by the minimum sample size.

Some key quality problems has been exposed in several years of quality supervision sampling inspection of industry products for HDPE silicore plastic duct, such as dimension, breaking elongation, performance of falling weight impact and ring stiffness. Quality consistency is an important indicator in evaluating product quality. Nondestructive testing can be used to evaluate the quality of the whole pan and batch of silicore plastic duct, and it will play important role in product quality controlling.

the paper introduces Cisco AAA certification, through the simulation practical the certification, it is a set of mechanisms using on the existing network, which can use user’s identifications, the net types, and the network equipment security comprehensively into providing the flexible delegated strategy for users, also taking the user operating records into ACS server. So as to the management of network safety by setting configuration password and using RADIUS or TACACS+server, besides these it is necessary to turn on the router managing users essential protocols. And the safety IP sub-net is sure to visit and record acting. The purpose in paper is blending the certification into campus security network management, to identify and manage different users for award corresponding permissions, then makes campuses network much more Systematic and safe.

This text has introduced a kind of design process on the basis of teaching administrative system facing target's modeling. During the design, we have used unified modeling language UML and modeling tool Rational Rose2002 Enterprise Edition analysis to conduct overall analysis and design. Meanwhile, we used Rose Delphi Link to produce the frame code of Delphies at the same time, so as to greatly improve the expansibility of the administrative system and the reusability of module .

the paper presents a brand new system about mine locomotive monitoring and management based on wireless video technology, which has high communication rate, strong anti-disturbance capability, more secret, longer distance and object recognizing on high speed moving and other technology advantages. These make the system suit for complex and harsh working environment underground. It uses optical cable to translate data for saving electric cable and decreasing installation and maintenance workload. The full-course real-time supervising improves the efficient of locomotive transportation management and makes locomotive schedule much more convenience.

Silver Nanoparticles has been prepared using the complex of carboxymethyl cellulose (CMC) and Polyvinylpyrrolidone (PVP) as a template and used as SERS substrate. The effect of the ratio of CMC to PVP on silver nanoparticles was discussed. Silver Nanoparticles were characterized by UV-visible spectroscopy, transmission electron microscopy and Raman spectroscopy. The results show that the ratio of CMC to PVP plays a crucial role in the performance of nanoparticles. TEM studies reveal that particles are mostly near-spherical in shape with an average size of 60-70 nm. The SERS enhancement of these silver nanoparticles was tested by using Rhodamine 6G (R6G) as a probe molecule. The silver nanoparticles prepared with the complex of CMC and PVP as a template have been shown to provide strong enhancements in the SERS spectrum of R6G. Keywords: Carboxymethyl cellulose; Polyvinylpyrrolidone; Surface-enhanced Raman scattering; silver; Template

Journal bearing in high-speed working conditions will generate a lot of heat, which affects its working performance. Based on hydrodynamic lubrication theory, a model of the thermal hydrodynamic lubrication was built, and the distributions of temperatures and pressures of the oil film were obtained from the simultaneous solution of generalized Reynolds, energy and viscosity-temperature equations. The results show that the temperature will increase and the pressure decrease of the lubrication oil film with the rising of the rotating speed, which will make the the bearing capacity decrease. Compared with the traditional isothermal model, the thermal hydrodynamic lubrication model is more consistent with the engineering practice.

It describes the types,the existing problems and three improved methods on the condensation air blower of roof-mounted automobile air-conditioning. It details a specific method, a practical circuit and the experimental results of the sensorless BLDC motor for condensing blower based on dsPIC30F4011 control,. According to the need of the current States on automatically climate air conditioning system (ACC system) , and the features of the roof-mounted automobile air-conditioning, we think it is more reasonable,the dsPIC30F4011 and the sensorless BLDC motor can be used for the the condensation air blower of automobile air conditioning.

One’s head pose can be estimated using face images. The hidden manifold of head pose in the high dimensional space can be successfully embedded into a 2 dimensional space using Kernel Principal Component Analysis (KPCA). A pose curve is gotten using KPCA train samples and new pose image is projected onto this curve. The pose angle can be estimated using interpolation method. The disadvantage of traditional linear method is conquered by using 2-D KPCA and the experimental results that the method is effective to estimate head poses. The kernel functions effects on estimation accuracy are also discussed.

Daqing Wuzhan gas field is a deformable low permeability gas filed. Based on the lab study of changing law of porosity and permeability with confining pressure, a numerical simulation model of deformable low permeability gas reservoir is established and is solved by using IMPES method. Comparing with the result of eclipse shows the method is valid. Field example shows the dynamic geological reserves of Wuzhan gas field is low and the new wells should be drilled at the area where there is production potential and larger effective thickness. Comparison of results obtained from different models with field data shows the result considering medium deformation is more reasonable.

By analyzing the quality elements of traffic engineering, the spectra structure of quality characteristics of all levels of projects and parameters for traffic engineering will be established. Combined with the requirements of JT/T828-2012, the compilation method of experimentation & test data reports can be determined. It will promote the level of management standardization and refinement for experimentation & test organization, and will further improve the accuracy and objectivity of experimentation & test data.

Data Reduction Factor (DRF) and the Super Efficiency DEA (SE-DEA) model are employed to study the energy saving and emission reduction efficiency of Shanxi Province. Based on Shanxi’s 2003~2010 panel data, firstly the public factors with economic significance are selected from many input and output indices by means of DRF; secondly the efficiency values during 2003~2010 are estimated by plugging the public factors, which are nonnegative after transformation by threshold method, in the input-oriented SE-DEA model; finally the DMUs are sorted and the efficiency value and scale returns of each unit are analyzed in details.

The repellent activitie of Cinnamomum japonicum oil against Aedes albopictus were investigated. The main volatile chemical components of the oil were qualitatively studied. The main results are given as follows. Cinnamomum japonicum oil providing absolute protection against Ae. albopictus in laboratory and field for 2.33 ± 0.63 h, 3.85 ± 0.21 h at concentration of 1.5 mg/cm2, respectively. A total of 28 compounds were identified. The main components of the essential oil were borneoll (28.30%), 1,8-cCineole (20.98%), (-)-bBornyl acetate (6.65%), linalool (5.94%), (-)-.alpha.-terpinol (5.87%), caryophyllene oxlde (5.11%). The results indicates that Cinnamomum japonicum oil has a great potential to be developed into a ecofriendly mosquito repellent.

GA-Bp network model was proposed. GA was used to optimize the initial real values population of Bp network, and optimizing crossover fraction was fulfilled. In addition, the modified GA-Bp was applied to predict the deformation of the surrounding rock around tunnels.

The data report format and contents between the various laboratories differ in a thousand and one ways. The project quality information cannot be compared with the others. The quality control and management is severely affected. By studying capital and normal data report format, a set of data report format is drew up for site laboratory, which will standardize the representation of test & detect data, which will be benefit to control quality and file the engineering data. The goal of standardized management and scientific management will finally be achieved.

Heavy-duty structure lifting operation involves a complicated lifting process, great technical difficulty and high safety requirements. Also, the material/human resources and time spent on heavy-duty structuring lifting operation have a direct impact on the safety, quality, progress and cost of the whole projects. Therefore, it has become a common critical concern of the construction engineering circle to adopt advanced, reasonable lifting methods, select proper lifting equipment, prepare pertinent safety & technical measures, minimize the duration of lifting operation and reduce project cost. This paper introduces an easy, high-efficiency, safe, reliable, economical and practicable heavy-duty steel channel lifting technology, wherein the channel is lifted wholly via a tubular gin pole-assisted, multi-point, high-position lifting method. There is no need for large tonnage lifting equipment and ideal site conditions. As this lifting technology is conducive to operating efficiency maximization and cost minimization while ensuring safety and quality, it is suitable for wide application in today’s technical environment which prioritizes energy saving and emission cuts.

Seeking for a scientific and reasonable predict model is the key point to ensure accurate and reliable prediction results for the land subsidence. In this paper, the research of subsidence area pointed out by picks the process of land subsidence which causes by the water reservoir that conforms to the characteristic of nonlinear dynamics, thus, a new model is established to solve the combinatorial weighted coefficients by using the predict precision, and a simple method is introduced to solve the grey model and neural network combination forecast model. Based on many examples, the new cusp catastrophe land subsidence model is proved to be very effective and much more accurate.

The use of fly ash is in harmony with the concept of sustainable development. This paper discusses the effect of replacing ratio of fly ash (FA), ambient relative humidity, temperature, curing age and w/c on carbonation of concrete made with low-volume FA. The process was accelerated in artificial carbonation laboratory by controlling 20% concentration of CO2, temperatures from 20°C to 60 °C and 30%-70% relative humidity. The contrastive results show that the carbonation model for predict carbonation depth has a nice performance.

Concrete quality evaluation is an important basic work for the concrete environmental management and protection. This paper presents a new concrete quality monitoring method based on principal component analysis-wavelet neural network combined model. First, the establishment of concrete quality evaluation index system, and then using principal component analysis to remove the relevance, overlap information of indicators, the representative indexes obtained were standardized and imported into the wavelet network neural model, the results of network study that used for the concrete quality comprehensively monitoring

The silver-modified sponge-like titanium dioxide arrays were prepared by a hydrothermal method. The effects of the hydrothermal reaction temperature, template agents were studied. The obtained products of Ag/TiO2arrays were investigated by scanning electron microscope in combination with X-ray diffraction. Results show that polyvinylpyrrolidone plays a key role in the formation of titanium dioxide arrays. Compare to the commercial P25 (Degussa), the optimized TiO2 array-structures exhibit an obvious enhanced photocatalytic activity, that enhancement is attributed to its sponge-like biomimetic structure and silver modification. The products have potential applications in degrading organic pollutants.

The thickness of metal base and anticorrosion is key indicators in evaluating the quality of corrugated sheet steel beams for guardrail, especially for double anticorrosion. The testing method in this paper is simple and convenient, accurate and reliable, which has been confirmed in engineering practice.

The Equivalent Linear Method is a common way used in earthquake engineering to analyze nonlinear site seismic response, but the response under strong motion is underestimated by the way. For analyzing nonlinear response more veritably, in the study, a time-domain nonlinear analysis method was proposed and used in a case for 1D seismic response analysis of soil layers under strong motion. The results obviously showed that, comparing with true nonlinear method, the Equivalent Linear Method underestimated in the case in natural period range of common civil engineering structures. The true nonlinear method adopted in the study is more fitful for nonlinear response of soil layers under strong motion.

A finite element method was developed to reveal the thermal characteristics of concrete with a cooling pipe, and the influence of cooling pipe on thermal field was calculated by the coupled fluid flow and solid heat transfer method. Temperature distribution along the pipeline was calculated and the mean Nusselt numbers on each section in the cooling pipe also were obtained. Numerical results show that the flow field and the temperature distribution were very complexly and the heat transfer was severely attenuated in the bend position, the outboard temperature of pipe was higher than the inboard temperature. In addition, in order to study the effect of the cooling pipe on thermal distribution, the temperature of different positions at the hydration time were compared with the no cooling results. The present results could be helpful to predict the temperature cracks in structure engineering.

Evolution process of optical polarization state in reflective fiber optic current sensor(R-FOCS) is complex, light wave travels from polarization maintaining (PM) fiber with linear polarization state, and light wave travels from sensing head with circular polarization state. Focused on characteristics of optical polarization state in R-FOCS, we analyze the characteristics of optical polarization state in R-FOCS, and demonstrate the methods to build optical polarization models by using Poincare sphere and Jones matrix respectively. Jones matrix provides a mathematically rigorous method of tracking optical polarization state, however, it often leads to a less intuitive description. Despite the mathematical complexity of some phenomena observed in R-FOCS, the Poincare sphere provides elegant and simple geometrical interpretations. The two methods are combined and offer both a mathematical representation and an intuitive interpretation of nonreciprocal polarization effects in R-FOCS.

Evolutionary game theory originated as an application of the mathematical theory of games to biological contexts, having the advantages of truly reflecting the diversity and complexity to provide theoretical basis to study macro-control group behavior. The evolutionary game theory-based modeling and stability analysis of subsidy policy on safety investment in SMEs is studied, and the simulation about the effect of the alteration of the ratio on the evolvement results is executed. The results indicate that the safety subsidy of local governments can enhance SMEs’ enthusiasm to invest. It has excellent significance to study further how to achieve equilibrium between SMEs and local governments using evolutionary game theory, and to provide theoretical basis to study operation mode of subsidy policy on safety investment in SMEs.