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The condition monitoring of seals is very important in the working process of the hydraulic system. However, it is often difficult because of the limitation of the structure. The purpose of this study is to find an effective way to solve it. With finite element analysis (FEA) software Ansys Workbench, and the O-ring is taken as the example for the comparative study of the contact strain between the O-ring and the sealing groove under normal condition and failure mode respectively. The results show that the contact strain on the sealing groove under normal condition and failure mode are different. A certain rule is presented as the working medium pressure, pre squeeze rate, sealing groove notch radius and temperature changes. It provide an important basis for further monitoring of O-ring failure through contact strain changes in sealing groove.

In the working process of hydraulic system, it is usually hard to match the operating parameters with the real-time load to get the optimized efficiency. This paper proposes an operating parameters matching and efficiency optimization method for hydraulic system based on data envelopment analysis(DEA). This method can provide the optimal input parameter scheme corresponding to the real-time load of system. Simulation experiments are carried out by AMESim. Results show that this method can improve the system efficiency by adjusting the input parameters to better match the output parameters on the premise of without changing the normal function of system. The study provides a theoretical basis for applying this method into practical engineering of hydraulic system efficiency optimization.

Traditional logistics brings damages to the environment, such as climate change, air pollution, water pollution, etc. Environmental logistics concerned more about improving the environmental sustainability compared to the traditional one. We find that it will help China to optimize the whole logistics system and minimize the damages caused by transportation, storage. And thus China will make new progress in logistics management, environmental protection and sustainable development.

Thermal conductivity is one of the key factors influence the heat exchange performance of Ground-coupled heat pump systems (GCHP), which is effected significantly by soil moisture content around the ground heat exchanger system. The clay thermal conductivity under moisture content of 0, 5%, 10%, 15%, 20%, 25% and 30% were determined through thermal conductivity probe experiment. The results showed a variation with three phases of the thermal conductivity changes with clay moisture content, that firstly, the thermal conductivity increased slowly with a moisture content of 0~5%, secondly, which sharply increased with a high positive linear correlation when the moisture content was 5%~25%, then the growth tendency was slow even began to fall, as well as the correlation equation of the second phase was fitted. This study provides methodological and theoretical references for the further research on the influence factors of thermal conductivity under various situations.

A digital mockup of hard rock tunnel boring machine was built in order to study the design method of these large equipments. Technology of digital mockup is introduced and the application background and practical requirement of tunnel boring machine has been discussed in this paper. The kinematics model and FEM model were built based on this digital mockup. The results of simulation experiment can be used to provide pre-feasibility validation and optimization of the equipment.

In order to clear the timeliness issues of metal magnetic memory signal value after unloading, we conduct some static tension experiments on some specimens in materials of KMN, which is commonly used in centrifugal compressors? Furthermore, we analyze the specimen, which is prefabricated artificial defects, on the surface normal magnetic field strength decay law with EMS-2003, the intelligent magnetic memory tester. The results show that: the surface magnetic field signal value is reduced by time after unloading, in other words it has certain timeliness.

There exist overfrequency issues of airframe vibration, instable fight conditions, inefficient airframe survivability and undeveloped cockpit’s eject-ability insides multi-rotor aircraft flights. This paper focuses on four-rotor aircraft researches via gathering inherent rotor attitudes with the inertial motion capture device. Based-on the resulting data analyses, the relations between flight attitudes and rotor performances are clearly figured out. This research also advances multi-rotor aircraft works, such as: drawing frameworks, evaluating simulations, designing control systems, and optimizing safety and stability properties.

Study on the load exerted on cutter head is very useful for the design and performance prediction of hard rock tunnel boring machines. A composite model based on smoothed particle hydrodynamics and finite element method was carried out using AUTODYN software to study the rock fragmentation mechanism of constant cross-section disk cutters in cutter head. The normal force, rolling force and side force on the disk cutters with different cutter radius were researched in the numerical simulation study. The results were verified by historical literature data. To obtain the distribution of the forces with different cutter radius, the loading of cutter head of a Ф5.75 hard rock tunnel boring machine were analyzed. The result shows that it is useful for cutter head’s design and its layout optimization.

In recent years, with the development of e-commerce, logistics is playing an increasingly important role in society. And the concept of "Green logistics" has been spreading, which stress higher demands on Chinese logistics industry. Business progress is inseparable from technological enhancement. RFID technology as the basis for Internet of Things, whose application in the logistics industry will have tremendous prospects. The article aims to provide discussions on the establishment and improvement of the information system for Chinese logistics industry by the introduction to causes, patterns, strengths and weaknesses of RFID practice.

As One of Features from other Languages, the Chinese Tone Changes of Chinese are Mainly Decided by its Vowels, so the Vowel Variation of Chinese Tone Becomes Important in Speech Recognition Research. the Normal Tone Recognition Ways are Always Based on Fundamental Frequency of Signal, which can Not Keep Integrity of Tone Signal. we Bring Forward to a Mathematical Morphological Processing of Spectrograms for the Tone of Chinese Vowels. Firstly, we will have Pretreatment to Recording Good Tone Signal by Using Cooledit Pro Software, and Converted into Spectrograms; Secondly, we will do Smooth and the Normalized Pretreatment to Spectrograms by Mathematical Morphological Processing; Finally, we get Whole Direction Angle Statistics of Tone Signal by Skeletonization way. the Neural Networks Stimulation Shows that the Speech Emotion Recognition Rate can Reach 92.50%.

Aero-Engine health management generally involves a series of activities over the period from the aerospace breaking down until it returning to normal, including signal processing, monitoring, health assessment, decision supporting, human-computer interaction, and so on. As one of the key technology of Aero-Engine health management, fault diagnosis plays a very important role on the safe operation of Aero-Engine. Currently, for effective challenging Aero-Engine health management, a fault diagnosis of Aero-Engine based on Principal Component Analysis (PCA) s proposed. Firstly, based on a variety of significant parameters of the collected information, principal component analysis model is established. Secondly, the fault diagnosis of engine operating conditions is realized by comparing the T2 statistic and Squared Prediction Error (SPE) statistic as an engine running in good condition threshold limits. Finally, through the variable's cumulative contributions diagram with the behavior of SPE overrun, the fault variables are effectively worked out. Experimental results show that the proposed PCA method can efficiently come true Aero-Engine health management o and has some engineering applications values.

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.

Port inventory is a very important part in iron ore supply chain. Through the inventory management, we can get the best inventory strategy to minimize the total inventory cost. The inventory management of the port iron ore can get a reasonable and feasible inventory management strategy through the dynamic planning model.

The hydraulic cylinder is an important actuator in hydraulic system, and its leakage has a great influence on the performance of the hydraulic system. Therefore, researching the accurate identification of hydraulic cylinder leakage fault is very important to eliminate leakage fault as soon as possible. Based on the fault mechanism, the paper proposes a fault diagnosis method for hydraulic cylinder based on displacement signal and pressure signal fusion. BP neural network and DS evidence theory are respectively used for fault mode identification. Through the research, it is found that combining the two methods can improve the identification accuracy of hydraulic cylinder leakage failure mode.

With the development of economy, online shopping has become more prominent, study found if a website has good quality dimensions will promote consumers to buy. Paper based on site characteristics, takes perceived risk and perceived emotional as intermediate variables using structural equation model (AMOS) to study consumers purchase intention. The results shown that the security impact on purchase intention by perceived risk, interactive and entertaining impact on purchase intention by perceived emotional, convenience and functionality directly impact on purchase intention.

This study has the hypotheses of the factors influencing customer satisfaction of the website features and model, and uses AMOS 7.0 structural equation analysis to process questionnaire data. According to the path coefficients of structure model and the indices of fit that verify the hypotheses, this study reaches a conclusion that the factors affect customer satisfaction of e-commerce mainly contain website economy, website security, website informative, followed by the convenience and website interactivity, and website popularity and entertainment has little impact on customer satisfaction. Most of the hypotheses of this study are supported by empirical research. And the conceptual model that customer satisfaction of e-commerce is decided by the website service quality consumers perceived and customers expectations is set up.

Due to the various organizations and production processes of the product life cycle involved in the process of the formation of discrete manufacturing product quality information, there are many uncertain factors, making the process have high complexity. How to describe this process accurately to identify potential problems in the process effectively is extremely important. Therefore, the paper presents the product quality formation process modeling method based on Petri net; explores how to use Petri net tool to describe the product material flow and information flow in the product quality information formation process, as well as how to apply the theory of Petri net to analyze the state of the process, thereby potential problems in this process can be identified effectively. The paper verifies the effectiveness of the method with an example.

Group buying--a new way of shopping online is emerging, customers can shopping by forming groups by themselves to persuade the sellers to reduce the price. Group buying sites greatly enhance the bargaining power between the customers and the merchants. This paper contributes to the using the factor analysis, nine factors including commodity information, trading levels, commodity inspection, the after-sales service, corporate image, website design Personality services, the quality of service and logistics distribution that will affect the customer satisfaction comes down to two factors, these two factors are defined based on Herzberg's two-factor theory, obtains the group buying customer satisfaction of the hygiene factors and motivation factors. Then based on the results give merchants more advise to improving customer satisfaction.

The main bearing is one of the primary friction pairs of a diesel engine. The lubrication condition affects the performance of the marine diesel engine directly. Continuous working time of main bearings is longer, load is higher and working condition is even worse especially in low medium speed marine diesel engine, making it difficult to form good dynamic pressure lubrication.Therefore, this paper takes a high-power marine diesel G32 with 9 cylinders as an example, calculates and analyzes the load, the orbit of main shaft center and the minimum thickness of oil film in each main bearing, providing the basis to estimate each main bearing’s lubricating condition, predicting each main bearing’s performance precisely and judging whether there exists abnormal working conditions in each main bearing.

According to the characteristics of large size, small clearance ratio, high oil film pressure and thin oil film thickness in the actual conditions of high power marine diesel engine bearing, this Paper analyzes oil film pressure distribution on inner surface of bearing bush based on the finite difference method, uses finite element method to establish the hierarchical model, and analyzes stress and strain distribution on bearing alloy. In addition, this Paper researches the changes of stress and strain distribution on bearing alloy layer when alloy layer thickness changes for the optimization design of high power marine diesel engine bearing bush.

The technology of infrared wireless communication offers us a wireless connection and communication mode that is low cost, high speed and short distance. IrDA infrared data association brings forward IrDA infrared communication protocol that is the base of a large number of equipments, interlink with infrared data interface. This paper introduces IrDA standard and the frame structure of IrDA standard. An improve analysis is presented linking processor of IrLAP.

Aiming at the question about armor training simulator whose image visual is not vivid and function is not perfect in our country [1, 6], the paper introduces RV engine in simulation training system of armored vehicle. It has researched establishment of entity and fire control system model based on RV, and then accomplished the simulation of range setting state, including the changing rule of gunner viewer-sight of the Image-stabilization fire control system, the principle on the measuring distance with laser, and the calculation of the location and height lead.

Train Movement Authority(MA) concerns train movement safety. This paper proposed a formal model for Chinese Train Control System-3(CTCS-3) based on train MA. Paper analyzed the rounded CTCS-3, formed MA computation models for various application functions, and finished MA hierarchical and functional computation models based on Colored Petri Nets(CPN). The results of experiment demonstrates that the model proposed in this paper is effective, it can reflect the whole information change and transmission process of CTCS-3 accurately, and can help to design and develop MA of CTCS-3.

By reviewing the application of stochastic hydrological models in flood control safety design, risk analysis, water conservancy project planning and scheduling in recent years in China, it is presented that stochastic hydrological models are good tools for optimizing decisions in planning, design and operation of water resources development and utilization. Also, it deals with the problems which are difficult to solve in traditional hydrological calculation method. Besides, it is focused on some work which should be improvedand popularized about stochastic hydrological models in the future.

This paper presents a three-dimensional nonlinear finite elemental analysis about the reinforcement concrete beams strengthened by bolting steel plate. The contact effects between the steel plate with reinforced concrete beam surface was simulated by developing the contact elements. The effect of strengthening is analyzed and the effects of the deformation and stress distribution of anchor bolt on the failure mode were investigated. It is declared that this strengthening method can obviously improve the capacity and stiffness of beam, and the flexural deformation of anchor bolt is key problem inducing the failure of strengthened beam. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

In this paper the important meaning of the system simulation in improving enterprise especially for discrete manufacturing is understood. Method of the design of processing workshop facility layout and specific implementation steps can be proposed by further in-depth study of the SSLP. I use eM-plant simulation optimization software for analysis to reduce he workshop production organization management and operating costs effectively. And it could use the analysis method of Bottleneck Analyzer to make statistical analysis. The paper puts forward effective feasible method in planning to layout of stone processing workshop for facilities, and making the logistics park to efficient, low cost operation [1, 2].

In order to detect the fault of automotive Electronic Control Units. In this paper, we proposed and implemented Controller Area Network (CAN) node management mechanism in the light of CAN technology standards and OSEK / VDX specifications. Besides, the standard protocols for analyzing low-speed CAN network application messages and monitoring network management messages had been developed. We utilized the vehicle network remote fault diagnosis platform and CAN analysis tool ZLGCANTEST to test the CAN data and analyze its real-time monitoring state. The experiment results indicate that CAN node management is capable of rapidly completing node fault detecting and promptly report node fault information for vehicle network remote fault diagnosis.

In this paper, the effect of the non-uniformity settlement of ground foundation on the upper frame structure is studied. It takes a four-story space frame structure with two spans as an example. The different pedestals are installed at the joint of column footing, which respectively form the fixed supported model and the elastic supported model. Basin shaped settlement is applied in each model. The result shows that the beams are principally suffered with the bending moment and the columns principally suffered with axial force, shear force and bending moment, and that the elastic support model has certain economy.

As a structural object of Petri nets, siphons are significant in the analysis and control of deadlocks in a Petri net. However, some existing siphon computation methods are quite time-consuming. In this paper, based on incidence matrix manipulation, a new method is proposed to compute a set of siphons in a class of Petri nets called systems of simple sequential processes with resources (S3PR). The proposed method consists of two algorithms: 1) computation of an unmarked maximal siphon and 2) obtain minimal siphons from an unmarked maximal siphon. A flexible manufacturing systems (FMS) example is used to illustrate the proposed method.