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A numerical simulation research was carried out on vortex and sound pressure level of the butterfly valve in the flow process based on FLUENT, which analyzed the variation of the vorticity and sound pressure level at different opening angles. There was an inverse pressure gradient in the orifice formed by the butterfly plate and pipe, which caused partial particle reflux on the back of butterfly plate in flowing, thus formed the vortex. The vortex formed on the back of the butterfly plate was decreased gradually, with the increasing opening angle of the valve in opening process. The noise was generated by the vortex separated and rupture in flowing. And the sound pressure level on the back of butterfly plate was decreased with the increasing opening angle. At the same time, the vorticity and the maximum sound pressure level position moved from the center to the rotation center of butterfly plate in opening process. The expanding orifice formed by butterfly plate upstream and the pipe and the tapered orifice formed by butterfly plate downstream and the pipe had the different throttling action to the fluid, which made the sound pressure level of upstream was higher than that of downstream in symmetrical position. The vortex generated by the separation of boundary layer would cause vortex excited vibration between plate and fluid, and then resonance occurred. The studies were carried out in the vorticity and the sound pressure level on the downstream of butterfly plate, and the changing law of those was found. It would provide a basis theory for reducing noise and avoiding vortex vibration of butterfly valve.

This paper analyzes the measured data on Yushiling dam blast vibration which affected by blasting Yushiling Tunnel Construction,the results show that the monitoring of the dam each measuring point are below the maximum blasting vibration safety control standards, measured master oscillator frequencies greater than 20Hz, does not cause the dam resonance, vibration and shock wave generated by a small deformation of the dam, the dam did not cause abnormal deformation, the result of dam safety assessment to provide a scientific basis, and provide reference for similar projects.

A new visualized fiber fence alarm system was put forward in this paper, which was used Sagnac interferometric sensor of optical fiber fence on the surrounding invasion of signal detection and positioning, and sent alarm information and video monitoring system linkage, in order that the monitoring equipment switch to intrusion scene view timely. Finally the video record the intrusion events. This visualized alarm system makes full use of advantages of optical fiber detection and video surveillance, which improved the level of intelligence of security system and the security performance of the system.

Introduction of value chain management thinking,systematically analyzed the internal operating costs and the external competitiveness costs of construction enterprises. Derived driving factors of the operating costs using internal value chain,and analyzed the competitive cost using the industry value chain.In the CCSES case study, proposed a few methods to control cost drivers and improvement strategies using the above analysis.

The rapid development of network raise the role of WAN. As a large-scale backbone network, the failure of network components can lead to huge loss of data and revenue. How to improve the data switching speed and Quality of Service of network data is more and more important problem which Internet Server Provides cared. Multi-Protocol Lable Switching (MPLS) is a new WAN technology which is currently being standardized by IETF. This paper analysise the architecture of MPLS and describe the mechanism of label switching protocol. In addition, this study analyses the encapsulation of data packet at the Label Switching Routers which is on the boundary of MPLS network. A Label Switching Path (LSP) is built by Label Distribute Protocol in core network. A conclution of “one time routed, more times switching” routed was reached.

The rapid development of electronic businesses raises the need for exchanging information between enterprise networks via internet. If a secure connection is necessary then a virtual private network (VPN) is essential. IPSec use encrypting and encapsulating technology in client device and establishes a secure tunnel connection. The private network built by IPSec technology can ensure good transmission performance and service quality over public networks. This paper analyses the architecture of IPSec and describes the process of creating a site-to-site IPSec VPN between header and branch of enterprise over internet. In addition, this study analyses the encryption at the boundary of the network and concludes a propose some practical problems need to consider inside enterprise network.

On January 2, 2014, had the thermal infrared remote sensing image (TASI) near the drain of the Chang Jiang nuclear power station in Hainan Province plant. Due to the effect of external factors, such as the sun azimuth, the data within a single band appeared brightness gradient phenomenon. It was not conducive to the seawater temperature retrieval. Through research and analysis, established a model for thermal infrared image brightness gradient of the seawater. Based on quadratic polynomial fitting method, simulated the law of each kind of water after threshold classification, and then used the simulated compensation correction factors to correct the original image, had obtained a good application effect.

With the help of the commercial FE package ANSYS, this paper presents a finite element (FE) model for analyzing coupled flutter of long-span bridges. This model models the aero-elastic forces acting on the bridge utilizing a specific user-defined element Matrix27 in ANSYS, by which stiffness and damping matrices can be expressed in terms of the reduced wind velocity and flutter derivatives. Taking advantage of this FE model, Transient dynamic analysis is carried out to determine the dynamic response of a structure under the action of pulse load, of which the damping ratio can be obtained by considering response peaks which are several cycles apart. The condition for onset of flutter instability turns into that, at a certain wind velocity, the structural system incorporating fictitious Matrix27 elements does simple harmonic vibration with zero damping ratios or near zero one. The damping ratio is completely calculated in post-analysis of ANSYS and the initial frequency is given by any value and the last frequency can be got by iterating several times. In order to validate the developed procedure, a classical case study on three hundred meter simple supported beam is provided.

This paper firstly analyses the related technology in video on demand system, then analysis the flow scheduling and advanced VOD system and proposes a new scheduling algorithm, simulation results on scheduling algorithm. The experimental results are analyzed. The paper presents research on application of VOD technology and scheduling algorithm in VOD server system. Finally, this paper implements a basic video on demand system. Experimental results show that the proposed method has high efficiency.

Given the issue that most of the parking lot intellectualized degree and management level is relatively low, this paper focuses on the function design based on Zigbee wireless sensor network, puts forward an intelligent parking lot management system based on Internet of things. This system mainly adopted CC2530 chip as the core of the Zigbee information processing unit to realize the short distance, low power wireless transmission. The intelligent parking lot management system this paper introduced can detect in individual's use of the parking space in the parking lot, and the number of vehicles in the parking lot.

From the perspective of commercial banks, put the financial supply chain in the principal-agent relationship which is multi-agent and of multiple sections. This paper analyzed the principal-agent relationship between different subjects and commercial banks and information asymmetry. Secondly it also analyzes the information risk of supply chain finance caused by asymmetric information from in three aspects as risk types, risk behavior and risk loss. Finally it gives the Suggestions and countermeasures aimed to financial risk in supply chain information. It provides reference to main body understanding and the information risk of supply chain finance.

Structural effect character is one of the important properties of soft clay. It has great influences on its physical and mechanical properties, especially on its deformation features. On the basis of the laboratory tests, the structural behavior of marine soft clay in Pearl River Delta region under the low frequency cyclic loading was tested and analyzed. Combined with both macro-analysis and micro-analysis, it was found that the structural character of the soft clay has great influences on both its compression deformation features and its shearing deformation features.

This study examined the impact of corporate governance on environmental information disclosure in the China context. Our data was based on Shanghai A-share companies for the period 2008 to 2011. We examined the effect of corporate governance from different aspects. We found that Outstanding shares rate, State-holding ratio, and CEO/Chairman duality negatively affect environmental disclosure index (EDI) significantly; Proportion of independent directors, supervisory board and board sizes positively affect EDI significantly. Our results indicate that in China, corporate governance does influence the extent of environmental information disclosure significantly.

The innovative value chain system and the operation mechanism were studied of the service enhanced construction. In the service enhanced construction era, value chain innovation system includes orientation system integration services, full life cycle project management and engineering general contracting system. The service enhanced construction needs perfect construction market environment, the trust and sharing information in business, coordinated management and knowledge management, to reconstruct the value chain system, to achieve the structural adjustment of the construction industry and to improve the core competitiveness of enterprises.

This paper presents a fault diagnosis method of BP neural network based on Levenberg-Marquardt learning algorithm. First, the use of principal component analysis to reduce the dimension of the fault sample reduced BP neural network input variables. Then use the Levenberg-Marquardt learning algorithm to adjust the network weights. Levenberg-Marquardt learning algorithm is combination of the Gauss - Newton algorithm and steepest descent algorithm. It has Gauss - Newton algorithm of local convergence and gradient descent algorithm of the global characteristic. So it has higher convergence speed, reduces the training time, to a certain extent, overcomes the problem of traditional BP network convergence speed slow and easy to fall into local minimum point. Simulation results demonstrate the correctness and accuracy of this fault diagnosis method.

The material is used by humans to manufacture the machines, components, devices and other products of substances. Association rules originated in the field of data mining, people use it to find large amounts of data between itemsets of the association. Apriori is a breadth-first algorithm to obtain the support is greater than the minimum support of frequent itemsets by repeatedly scanning the database. This paper presents the construction of materials science and information model based on association rule mining. Experimental data sets prove that the proposed algorithm is effective and reasonable.

In this paper, a stable adaptive control strategy was proposed to improve the adaptive ability of thrust system of shield machine. The control strategy is composed of internal pressure feedback loop control and external advanced single neuron PID loop control. Its effectiveness was finally demonstrated by the result of AMESim-Matlab/Simulink Co-simulation.

The building materials used in building materials collectively referred to as building materials. New building materials, including a wide range of insulation materials, insulation materials, high strength materials, breathing material belong to the new material. Collaborative filtering process is based on known user evaluation to predict the target user interest in the target, and then recommended to the target user. This paper proposes the development of building materials recommendation system based on Collaborative filtering. Experimental data sets prove that the proposed algorithm is effective and reasonable.

Wooden box designing is usually carried out in SolidWorks or such general CAD systems. By secondary development on general CAD system using high level programming language such as Visual Basic, we can create a dedicated CAD system for wooden box. However these dedicated systems are mostly local computer based and not easy for sharing on Internet. In this paper, a web-based CAD system for wooden box has been established by combining PHP language and MySQL database with a localized dedicated CAD system for wooden box. With this system, we can design wooden boxes on the webpages without the installation of any CAD software in local computers, thus sharing the design system and results on Internet.

With China's rapid economic growth, Environmental pollution and ecological damage is becoming more serious. City environment problems become more and more get attention.,but,Small town environmental protection and management is a relatively weak link. Through the Xiaogan Anlu district environmental investigation, A comprehensive analysis of the Anlu environmental pollution source and pollution causes, And on this basis,to concluded the environmental pollution control measures about small town.

Tamper, the core equipment of tamping vehicle, is used to complete the work of maintenance and construction in the railway field. Based on international tamping technology and existing problems, a new type of electrohydraulic exciter applied on the tamper is proposed. It mainly consists of spin valve with high speed and micro-displacement double-functioned hydraulic cylinder. In this paper, AMESim Based Dynamic Modeling is carried out to early explore the relationship between operating frequency, axial conducting width of valve orifice and the displacement, velocity, acceleration, vibration force, load pressure, load flow rate. The results indicate that the new electrohydraulic exciter can meet the design requirement well and realize the flexible adjustment of amplitude and frequency through rotational speed control of step motor. Therefore, it adapts to different working environment including hardened ballast and loose ballast. This simulation can not only enrich relative researches of electrohydraulic exciter, but also provide theoretical foundation and practical direction for optimization of device design.

To study the mechanical evolution rule of the supporting part in the process of the reinforced concrete chimney blasting demolition, a finite element model based on a practical project is established by explicit analysis software LS-DYNA. By means of four different Angle blasting cut finite element models, the stress distribution of the supporting part and neutral axis moving rule is drawn. It will help to develop the theory of the reinforced concrete chimneys blasting demolition.

Wind turbine always run in complex environment, as the key components of wind turbine, it is extremely important to test wind turbine bearings properties, so we need develop a testing machine to test their properties. The static strength and dynamic properties of testing machine key components of 3MW wind turbine bearing were analyzed with the finite element software ANSYS to obtain the strength and stiffness check as well as the optimizing design of testing machine key components of wind turbine bearing. The strength was checked and satisfied with the demand of material strength. The former five orders natural frequencies and corresponding modes were obtained, which provides scientific basis for future design．

A new type of swelling solution is developed, which is applied for the pre-treatment of plating-through-hole (PTH) of print circuit board (PCB) made up of high Tg epoxy resin substrates. The results show that the best formula is 144 organic esters 200g/L and hexylene glycol 2g/L. The treatment temperature and processing time is 60°C and 6min, respectively. Under the optimal conditions, the residue caused by drilling can be removed completely through the process including swelling, oxidation and neutralization.

In order to meet the running needs of the first-stage construction in the middle line of South-to-North Water Transfer Project, the canal lining of both sides of Yellow River Tunnels Project need the use of mechanized equipment construction in order to improve the quality and efficiency of lining construction, there is a need to study the feasibility of the use of polypropylene fiber concrete instead of reinforced concrete in canal lining. This paper analyzes the effect of polypropylene fiber on concrete shrinkage and crack resistance. The results show that all three polypropylene fibers have properties of a low density and high elongation, the dispersivity test results show that dispersivity is better when stirring fiber A after a certain period of time. After the incorporation of polypropylene fibers, the concrete splitting tensile strength is significantly increased, altogether with ultimate tensile value and frost resistance. The incorporation of polypropylene fibers increases the tensile strength of concrete and improve the toughness of it. Compared with standard concrete, the early shrinkage of polypropylene fiber concrete is significantly lower, the incorporation of polypropylene fibers can take the place of steel mesh in concrete cracking, especially in the early control of concrete cracks, it can effectively prevent and suppress the cracks formation and development. This paper recommends the concrete proportioning parameters meeting the requirements of canal lining concrete technology and construction.

Hydraulic thrust system is a critical part of shield tunneling machine. The precise control of the thrust force is a significant task of thrust system during tunneling excavation. In this paper, an operation principle of the hydraulic thrust system test rig is illustrated. Taking into account the variable deadband nonlinear characteristics of proportional relief valve which is used for regulating the thrust pressure, several compensation control strategies are adopted to achieve the precise control of thrust force. Analysis and comparison which bases on simulation and experiment is done at last. The result shows that Fuzzy control can both eliminate the error and reduce the adjustment time which can basically meet the requirement of practical tunnel excavation.

The paper analyzes the characteristics of an intelligent transportation system (ITS) to explore the impact on urban transport of the ideas from “the Internet of Things (IOT)” before its official appearance, and further outlook for the driving force from smart traffic guided by IOT.

The vapor and gas permeabilities of the polyethylene films, casting polypropylene films and nylon films were tested in the paper. The keeping fresh performances were analyzed. It was found that the life time of vegetable packaged by films with high gas permeability is longer. The films with high vapor permeability reduce the accumulation of water droplets, but the leaves of vegetable change from green to yellow for lack of oxygen. It shows that the gas permeability of the film is more important than its vapor permeability for the vegetable storage. The family should choose the films with high gas permeability and appropriate vapor permeability to store vegetables.