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This paper is concerned with the diagnostic issue of the open-circuit fault for the three-phase full-bridge rectifier based on an autoencoder-based deep neural network (AE-DNN). Firstly, the preliminary of the AE-DNN is briefly introduced. Then, the fault diagnosis model is presented for the open-circuit fault of the three-phase full-bridge rectifier. Finally, the superiority and effectiveness of the AE-DNN based fault diagnostic system is verified by several simulation experiments. It is concluded that the AE-DNN based fault diagnostic system can automatically extract and learn the features from the raw fault data and perform more robust ability to the noisy signals.

Wireless sensor networks play an important part in forestry monitoring and sensing. LoRa low-power wide area network technology is based on CSS (Chirp Spread Spectrum) and provides new technical means for forestry wireless monitoring, sensing and other forestry applications. For the needs of the forestry application, the experimental analysis about the wireless transmission characteristics of LoRa in forest lands is conducted. Various factors such as different antenna heights and different data packet lengths, which had important influence on transmission characteristics in forest, are analyzed. The research results show that LoRa technology had a good transmission effect among forest and is expected to be candidate for forestry monitoring and sensing in the future.

To handle the fault diagnosis of multilevel inverter, a new approach based on hybrid intelligent algorithms has been proposed in this paper. Firstly, the wavelet packet transform (WPT) is applied for the multi-scale wavelet packet decomposition of the fault signal, and the fault feature vector is extracted from the reconstructed wavelet packet energy. Then, the principal component analysis (PCA) is employed to extract the principal information with lower dimension. Finally, the BP neural network (NN) is used for the fault diagnosis and identification. The simulation results show that the proposed method is more accurate for the fault diagnosis of multilevel inverter than traditional methods and more robust to the noise of fault signals.

The purpose is to locate the fault of coal mine drainage system quickly and accurately, and then establish a fault diagnosis of the underground drainage fuzzy Petri net system model based on BP optimization algorithm. On the basis of the traditional fuzzy Petri net model, the BP optimization algorithm with momentum factor is added to improve the accuracy of the algorithm, the S-type continuous functions are used to express transitions enabling and the new tag values in out-place after transitions firing respectively. In addition, through training on the vibration signal measured, new momentum is added based on the traditional parameters correction formula to optimize the weights and thresholds in the model. Through analyzing the results of experiments, we can summarize that the proposed model can accurately and quickly locate the causes of the underground drainage system fault.

This paper is concerned with the fault diagnosis of three-phase full-bridge rectifier. A new approach is proposed to extract the fault features in both frequency and time domain. The integrated features are used for the training of an LM-BP neural network, which is then applied for the fault classification. The simulation experiments are implemented on the fault diagnosis model built in MATLAB/Simulink, and the success of the approach has been confirmed by the simulation results.

Customer relationship management (CRM) has a hot issue in the field of modern business management. In fact, CRM is the theory and mode of customer knowledge management in nature. The level of customer knowledge management competence is important to implementing CRM. Therefore, this paper aims to establish a comprehensive index system of customer knowledge management competence based on knowledge management and Balanced Scorecard, and then proposes a tentative theoretical model for performance evaluation. The hierarchical index system includes business process flow, customer, learning and growth as well as sales performance, these above abilities constituted customer knowledge management competence and then become the important source of sustainable competitive advantages. Lastly it constructs the comprehensive model to evaluate customer knowledge management competence by applying AHP. The study is expected to provided a theoretical base of customer knowledge management and provide practical implication for enhancing busyness CRM level.

The logistics industry has played a more and more important role in the modern economic development. This paper analyzed the input-output relation on modern logistics industry and the other industries with Chinese input and output data, and calculated the effect coefficient, sensitivity of dispersion coefficient, production spread effect and price spread effect of logistics industry to the other industries. The results of the study showed that, the strongest reliance of logistics industry was the second industry, the second was the third industry, and the first industry was the weakest, the promoting function of logistics industry to China's economy was smaller than that of the second industry and the third industry, just above the first industry. Finally this paper put forward some further policy suggestions to promote the development of China's logistics industry.

This paper analyzed the relationship of environment pollution and economic growth by the data of 1980–2009 in China. The results showed that: the relationship of environment pollution and economic growth further verified the EKC hypothesis; from the specific indicators, the relationship of industrial wastewater emissions and per capita GDP displayed the type of N, and the relationship of industrial waste gas emissions, industrial solid waste production and per capita GDP both displayed the type of U. Since China's reform and opening-up policy, the economic growth and industrialization level both have being based on the cost of the environment, therefore, for maintaining the sustainable development of economy, China must deal well with the relationship of environment pollution and economic development.

Point primitives have experienced a major renaissance in recent years, and considerable research has been devoted to the aspects of efficient representation, modeling, processing, and rendering of point-sampled geometry respectively. However, the study of integrated platform based on point primitives is not as much as that of individual technologies on point primitives. The paper comes up with a point-based digital modeling platform after a brief overview of point-based computer graphics. This platform is designed according to the pipeline of point processing with various algorithms implanted as plugins.

By the analysis of logistics development promoting the division of labor, this paper calculated the similar coefficient of 28 manufacturing industries by the panel data of 1990–2008 in the Yangtze River Delta of China. The division of labour standards was as the explained variable, and the logistics development level including the per capita output and network density were as the explanatory variables, illustrating the logistics in promoting development of the division of labor. The results showed that logistics can significantly promote the development of the division of labor.

The paper analysed the efficiency of logistics industry in 31 provinces of China in 2009 by three-stage DEA model. The empirical results are as follows: firstly, the technical efficiency of 31 provinces is low, with the average of 0. 468, and the reason is the lack of scale efficiency; secondly, the development of logistics industry in East, Central and West of China differs wildly, specifically speaking, the one in East of China is the best and the one in West of China is the Worst; thirdly, if the effects of exogenous environmental variables and random shocks are not controlled, the pure technical efficiency of 31 provinces will be underestimated, and scale efficiency value will be often overestimated which will lead to the underestimation of comprehensive technical efficiency.

This paper measured the coordinated degree of transportation and economic development, and made a comparative analysis with the data of 31 provinces in China by the DEA method. The results showed: the coordinated degree of transportation and economic development in China was low, the average support degree of traffic system for economic development was 0.632, and the average degree of economic development for transportation was 0.753. From the three regions of east, center and west, the coordinated degree of transportation and economic development in eastern region was higher than that in the midwest.

The primary purpose of this study is to provide simple formulas for estimating the design wind loads denoted as gust effect factor for large-span domed roofs considering their dynamic response under wind excitation. In this paper, systematic parameter analysis for the gust effect factor of Kiewitt6-6 type domed roof structures have been performed with random simulation method in time domain, including geometric parameters, structural parameters and aerodynamic parameters. Moreover, an empirical formula for the gust effect factor is provided as a function of these parameters based on a statistical analysis, which can be conveniently used in wind-resistant design of these structures. The results indicate that the geometric parameters are the most important factor influencing the wind-induced response of domed roof structures, and the gust effect factor is well-proportioned, which is 3.0∼3.2 as a reference for the wind-resistant design.

The vertical impact damping system with multi-degree and multi-parameter has a complicated non-linear essence. To recognize its motion characteristics deeply, the paper experimentalized on cantilever beam damper system. First the mode parameters and inspiriting residences of the experiment device were identified, and after impact force with different frequencies and amplification were imposed on the system, lots of experiment data were gained. By plotting response phase figures of the system and combining experimental phenomena which could be observed, some conclusions about the non-linear of vertical impact damping system were drawn, what would provide references for many engineers.

Long-span continuous rigid bridge is sensitive to wind actions on largest double cantilever stage before closure. In order to analyze the performance of anti-wind during Rongjiang super-bridge construction, worst-case analysis of wind-induced response for several wind loads including various wind directions and attack angles have been performed using random simulation method in time domain. Based on the worst-case analysis, some measures for increasing its performance of anti-wind are discussed due to non-symmetric wind loads. The results indicate that the wind loads with +15° wind direction and +6° attack angle is the worst-case on largest double cantilever stage. In addition, the brace strut can increase the performance of anti-wind effectively, which would be a logical advice during bridge construction.

In order to determine the optimized parameters and offer logical advice for the design of truss and string structure, systematic parametric analysis for the mechanical behavior of the structure have been performed using ANSYS finite element software. Based on the discussion of effect with different factors, including ratio of string height to structural span, ratio of arch height to structural span, pre-tension value of the string, size of the truss, the optimized parameters for the design of truss and string structure are obtained. The results indicate that: (1) The ratio of string height to structural span (expressed as f 1 /L), and ratio of arch height to structural span (expressed as f 2 /L), are the most important factors influencing the mechanical behavior of the structure. The appropriate range of these two parameters is 0.05∼0.1 for f 1 /L and 0.05∼0.125 for f 2 /L respectively. (2) The pre-tension value of the string depends on the structural span, and the appropriate range of this parameter is 1200kN∼1400kN for the truss and string structure whose span is 110m. Moreover, the pre-tension value of the string would increase 200KN when the structural span increases 10m. (3) There is very little effect of the size of the truss for the mechanical behavior of the structure.

Viscoelastic structure, a type of passive energy dissipation structure, is widely applied in wind-resistant and aseismic structure because of its excellent performance in vibration suppression. The equations of motion under multi-dimensional seismic loads is formulated using the state space theory in this paper. The seismic response including translational response and lateral-torsional coupling response of a 6-story viscoelastic structure under seismic ground motion is analyzed respectively. Furthermore, it is emphasized on the effect of lateral-torsional coupling component in the analysis of multi-dimensional seismic response, and the characteristic of the rotational component in seismic loads. The results indicates that the effect of lateral-torsional coupling component cannot be ignored in the seismic response of eccentric viscoelastic structure, and the effect of lateral-torsional coupling increases with eccentric distance. Besides, the rotational component influences the seismic response in a certain way: the effect of rotational component increases with structural span, and its proportion in the multi-dimensional seismic response decreases with eccentric distance.

Pulverized coal with a mass average diameter of 69 μm and a real density of 1444 kg/m 3 was transported at an experimental bench for powder pneumatic conveying at pressurized conditions (up to 0.84 MPaA). Flow patterns of the pipe flow were observed by ECT (Electrical Capacitance Tomography) technologies. Differential pressures in horizontal pipes were measured. The ECT images showed a comprehensive evolvement of flow patterns with decreasing superficial gas velocities, consistent with Geldart's and Pan's descriptions. The differential pressures fluctuated in different modes for different gas-solid flow patterns inside the pipe. This paper indicated the differential pressure fluctuation as a useful feature to predict flow patterns at horizontal pipes.

The traditional DEA model didn't consider the importance of input and output indicators when it analyzed the relative effectiveness of each DMU. In fact, the importance of the various indicators is greatly different for the demand side in terms of logistics services. This paper chooses the various input and output indicators by AHP, Especially considers the difference of indicators for demand-side and selects input and output indicators with high weight which can greatly improve the reliability of evaluation results.

MSR (moisture separator reheater) has an important effect on the safe and economic operation of the steam turbine unit in the nuclear power plant. The thermodynamic calculation is the basic of design and operation of MSR. In this study, a new method of thermodynamic calculation of MSR is proposed. The calculated results indicated that the method can be used for the primary design and the check of heating surface area in MSR. Furthermore, the results verify previous research on the condensation in horizontal tube.

From learnerpsilas personality, research the human-computer interaction system in the LAN education; build up the theory of the human-computer interaction in the education LAN, analyze the human-computer interaction system character, according to its character, set up a human-computer interaction system model based on the learner's personality, analyze the key technology, accomplish the key technology in the personality of human-computer interaction. Just need to change a little software of the system, then it is suitable to the human-computer interaction in the industry control and machine auto control.

Surrounded noises degrade both audio and video qualities in a multimedia environment. This paper applies Gabor expansion to passive noise reduction of speech signals. The noise reduction method and performance via Gabor expansion are studied. The Gabor expansion with Gaussian prototype function has a property that its time and frequency product is minimal. The property makes the noise-only segment more clearly and the noise estimate more robustly.