A New MPEG-2 Rate Control Method Based on Model Classification

The paper proposed a new MPEG-2 rate control method that is based on model classification. The macro-blocks are classified according to their prediction errors, and different parameters are used in the rate-quantization and distortion quantization model. The different model parameters are calculated from the previous frame of the same type in the process of coding. These models are used to estimate the relations among rate, distortion and quantization of the current frame. Further steps, such as R-D optimization based quantization adjustment and smoothing of quantization of adjacent macroblocks, are used to improve the quality. The results of the experiments prove that the technique is effective and can be realized easily. The method presented in the paper can be a good way for MPEG rate control.     

Modeling the effect of environmental conditions on reliability of wind turbines

The climate condition of a wind farm has a significant influence on the reliability of wind turbines. The climate condition varies with season in a year and hence the reliability changes in a complex way. The purpose of this paper is to model the effect of climate condition on field reliability of wind turbines. The reliability is measured by monthly-averaged mean time between failures(MTBF), and the climate conditions are described by variables of monthly-averaged temperature, relative humidity, rainfall and wind speed. Referring to the physicsof-failure models in accelerated life testing(ALT), we develop a quantitative relation between the MTBF and the climate variables. For a set of field data, the model parameters are estimated by regression, and the insignificant variables are gradually deleted based on the P-value of the regression coefficients. The resulting model is useful for maintenance workload forecasting and preventive maintenance planning, and has a potential to be used in online failure prediction.     

Application of Nonlinear Predictive Control Based on RBF Network Predictive Model in MCFC Plant

This paper described a nonlinear model predictive controller for regulating a molten carbonate fuel cell (MCFC). A detailed mechanism model of output voltage of a MCFC was presented at first. However, this model was too complicated to be used in a control system. Consequently, an off line radial basis function (RBF) network was introduced to build a nonlinear predictive model. And then, the optimal control sequences were obtained by applying golden mean method. The models and controller have been realized in the MATLAB environment. Simulation results indicate the proposed algorithm exhibits satisfying control effect even when the current densities vary largely.     

Fault tree analysis of feeding control system for computer numerical control heavy-duty horizontal lathes with multiple common cause failure groups

The lathes are basic machine tools for manufacturing cylindrical parts. In recent years, the DLseries computer numerical control(CNC) heavy-duty horizontal lathes(HDHLs) have been widely used in the transportation, energy and aviation industries. High availability of the CNC heavy-duty lathes is demanded to guarantee the efficiency and benefit of these manufacturing industries. As one of the key subsystems of the HDHLs, the feeding control system is studied in this paper on reliability modeling and reliability analysis. The fault tree analysis(FTA) method is used for reliability modelling of the feeding control system. Considering the multiple common cause failure groups(CCFGs) existing in the system, a modified beta factor parametric model is introduced to model the common cause failure(CCF) in system. The reliability of feeding control system is then obtained and the effect of CCF on the reliability of the whole system is studied as well.     

Piecewise Linear Analysis for Pseudo-elasticity of Shape Memory Alloy （SMA）

Based on the Brinson constitutive model of SMA, a piecewise linear model for the hysteresis loop of pseudo-elasticity is proposed and applied in the analysis of responses of an SMA-spring-mass system under initial velocity activation. The histories of displacement and velocity of the mass, and the response of stress of SMA are calculated with Brinson‘s model and the piecewise linear model. The difference of results of the two models is not significant. The calculation with piecewise-linear model needs no iteration and is highly efficient.     

THE DLSTRIBOTED MCU MODEL FOR SYNCHRONOUS REAL-TIMETELETEACHING

Aiming at issues on multimedia communication in synchronous real-time teleteaching (SRT) systems over IP network, a 4-tuple structural mode of multimedia communication is proposed in the paper, and an SRT-oriented distributed MCU model is built according to the mode. Moreover, the mechanism of multicast communication across subnets is discussed. The distributed MCU model has been applied successfully in our interactive synchronous real-time telesteaching system RealClass and has shown good extendibility in operation.     

Modification to a Semi-selective Medium for the Isolation and Quantification of the Nematophagous Fungus of Pochonia chlamydosporia

Pochonia chlamydosporia (formerly Verticilli-um chlamydosporium) is a common nematophagousfungus with widespread distribution. Its occur-rence as a facultative parasite of sedentary stagesof endoparasitic nematodes has been well docu-mented[1]. It is thought to be one of the responsi-ble factors for a long-term stable suppression of ce-real cyst nematodes in the UK[2]. The biocontrolpotential of this fungus has been investigated forthe management of plant-parasitic nematodes on arange of agri…     

Feature extraction and modeling of welding quality monitoring in pulsed gas touch argon welding based on arc voltage signal

Arc sensing plays a significant role in the control and monitoring of welding quality for aluminum alloy pulsed gas touch argon welding （GTAW）. A method for online quality monitoring based on adaptive boosting algorithm is proposed through the analysis of acquired arc voltage signal. Two feature extraction algorithms were developed in time domain and frequency domain respectively to extract six statistic characteristic parameters before removing the pulse interference using the wavelet packet transform （WPT）, based on which the Adaboost classification model is successfully established to evaluate and classify the welding quality into two classes and the classified accuracy of the model is as high as 98.81%. The Adaboost algorithm has been verified to be feasible in the online evaluation of welding quality.     

A data model applied to the knowledge-based ICAS

Image-guided computer aided surgery system (ICAS) contributes to safeness and success of surgery operations by means of displaying anatomical structures and showing correlative information to surgeons in the process of operation. Based on analysis of requirements for ICAS, a new concept of clinical knowledge-based ICAS was proposed. Designing a reasonable data structure model is essential for realizing this new concept. The traditional data structure is limited in expressing and reusing the clinical knowledge such as locating an anatomical object, topological relations of anatomical objects and correlative clinical attributes. A data structure model called mixed adjacency lists by octree-path-chain (MALOC) was outlined, which can combine patient's images with clinical knowledge, as well as efficiently locate the instrument and search the objects' information. The efficiency of data structures was analyzed and experimental results were given in comparison to other traditional data structures. The result of the nasal surgery experiment proves that MALOC is a proper model for clinical knowledge-based ICAS that has advantages in not only locating the operative instrument precisely but also proving surgeons with real-time operation-correlative information. It is shown that the clinical knowledge-based ICAS with MALOC model has advantages in terms of safety and success of surgical operations, and help in accurately locating the operative instrument and providing operation-correlative knowledge and information to surgeons in the process of operations.     

Building and Researching the Bidding Model Based on the Cost of Power Plant

A bidding model of neural network was presented to pursue the largest benefit according to the policy of separating power plants from network and bidding transaction. This model bases on the cost of power plant and its research object is a power plant in the market. The market clearing price (MCP) can be predicted and an optimized load curve can be decided in this model. The model may provide technical support for the power plant.     

A new algorithm to automatically extract the drainage networks and catchments based on triangulation irregular network digital elevation model

A new algorithm to automatically extract drainage networks and catchments based on triangula- tion irregular networks （TINs） digital elevation model （DEM） was developed. The flow direction in this approach is determined by computing the spatial gradient of triangle and triangle edges. Outflow edge was defined by comparing the contribution area that is separated by the steepest descent of the triangle. Local channels were then tracked to build drainage networks. Both triangle edges and facets were considered to con- struct flow path. The algorithm has been tested in the site for Hawaiian Island of Kaho＇olawe, and the results were compared with those calculated by ARCGIS as well as terrain map. The reported algorithm has been proved to be a reliable approach with high efficiency to generate well-connected and coherent drainage networks.     

Research on hydrogen environment fatigue test system and correlative fatigue test of hydrogen storage vessel

A 70 MPa hydrogen environment fatigue test system has been designed and applied in the manufacture of a hydrogen storage vessel. Key equipment is the 80 MPa flat steel ribbon wound high pressure hydrogen storage vessel. A reasonable stress distribution has been realized, that is low stress in the liner of the pressure vessel and even stress in the flat ribbon layers. This optimal stress distribution is achieved through the adjustment of the prestress in flat steel ribbons. A control system for the fatigue test system has also been designed. It consists of a double control model, i.e. manual control and automatic control, to satisfy different experimental requirements. The system is the unique one that can be used in the real hydrogen environmental fatigue test system in China. An experiment for the 70 MPa onboard composite material hydrogen vessel has been carried out on the system. The experimental result from this test is in close agreement with the practical operating conditions.     

Design，Calculation and Model Test of Zhongshan Bridge

Zhongshan Bridge is a kind of steel arch bridge with a particular space-combined structure．The rationality of design．accuracy of theoretical calculation and reliability of transportation were studied．Its design，FEM calculation of stresses and strains，and model test were introduced in detail．The theoretical analysis and model test verified that the design was reliable and safe．The simulated stresses，rigidity and stability，which are based on the selected loading system and cross-section geometry，satisfy the related design standards．Some of the issues that need to be considered in the real bridge construction were also discussed．     

A probability approach to anomaly detection with twin support vector machines

AbstractClassification of intrusion attacks and normal network flow is a critical and challenging issue in network security study. Many intelligent intrusion detection models are proposed, but their performances and efficiencies are not satisfied to real computer networks. This paper presents a novel effective intrusion detection system based on statistic reference model and twin support vector machines (TWSVMs). Moreover, a network flow feature selection procedure has been studied and implemented with TWSVMs. The performances of proposed system are evaluated through using the fifth international conference on knowledge discovery and data mining in 1999 (KDD’99) data set collected at MIT’s Lincoln Labs and the results indicate that the proposed system is more efficient and effective than conventional support vector machines (SVMs) and TWSVMs.     

Mathematical approach for fleet planning under complicated circumstances

In order to facilitate the scientific management of large-sized shipping companies, fleet planning under complicated circumstances has been studied. Based on multiple influencing factors such as the techno-economic status of ships, the investment capacity of company, the possible purchase of new ships, the buying/selling of second-hand vessels and the chartering/renting of ships, a mixed-integer programming model for fleet planning has been established. A large-sized shipping company is utilized to make an empirical study, and Benders decom- position algorithm is employed to test the applicability of the proposed model. The result shows that the model is capable for multi-route, multi-ship and large-scaled fleet planning and thus helpful to support the decision making of large-sized shipping companies.     

Development of an Autonomous Flight Control System for Small Size Unmanned Helicopter Based on Dynamical Model

It is devoted to the development of an autonomous flight control system for small size unmanned helicopter based on dynamical model. At first, the mathematical model of a small size helicopter is described. After that simple but effective MTCV control algorithm was proposed. The whole flight control algorithm is composed of two parts: orientation controller based on the model for rotation dynamics and a robust position controller for a double integrator. The MTCV block is also used to achieve translation velocity control. To demonstrate the performance of the presented algorithm, simulation results and results achieved in real flight experiments were presented.     

THE EXPERIMENTAL STUDY ON THE CELL APOPTOSIS AND EXPRESSION OF BCL-2 PROTEIN IN INTRACEREBRAL HEMORRHAGE IN MODEL OF RATS

Intra-cerebral hemorrhage is a common clinicaldisease,with a high mortality and morbidity.So itis one of the clinical hot topics.It has been foundinrecent years that there is a close relationship bet weenthe cell apoptosis and the course or prognosis of in-tra-cerebral hemorrhage.Bcl-2,as the apoptosis-adjusted gene,plays ani mportant role in the courseof cell apoptosis,but the mechanis min the cell ap-optosis in intra-cerebral hemorrhage remains un-clear.In this experi ment,with the model bui…     

Leave the expressway or not？ Impact of dynamic information

This study investigates drivers＇ diversion decision behavior under expressway variable message signs that provide travel time of both an expressway route and a local street route. Both a conventional cross-sectional logit model and a mixed logit model are developed to model drivers＇ response to travel time information. It is based on the data collected from a stated preference survey in Shanghai, China. The mixed logit model captures the heterogeneity in the value of ＂travel time＂ and ＂number of traffic lights＂ and accounts for correlations among repeated choices of the same respondent. Results show that travel time saving and driving experience serve as positive factors, while the number of traffic lights on the arterial road, expressway use frequency, being a middle-aged driver, and being a driver of an employer-provided car serve as negative factors in diversion. The mixed logit model obviously outperforms the cross-sectional model in dealing with repeated choices and capturing heterogeneity regarding the goodness-of-fit criterion. The significance of standard deviations of random coefficients for travel time and number of traffic lights evidences the existence of hetero- geneity in the driver population. The findings of this study have implications for future efforts in driver behaviormodeling and advanced traveler information system assessment.     

Sensitivity Analysis of the Hydrodynamic Coefficients in 4 Degrees of Freedom Ship Manoeuvring Mathematical Model

The S-type test is simulated based on a ship manoeuvring mathematical model of 4 degrees of freedom(4-DOF);simultaneously,sensitivity analysis of the hydrodynamic coefficients in the mathematical model is implemented by using an indirect method.The mathematical model is simplified by omitting the coefficients of smaller sensitivity according to the results of sensitivity analysis.The 10°/10° zigzag test and 35° turning circle manoeuvre are simulated with the original and the simplified mathematical models.The comparison of the simulation results shows the effectiveness of the sensitivity analysis and the validity of the simplified model.