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The direct torque control (DTC) system of the traditional asynchronous motor has many disadvantages, such as complex modeling and large amount of calculation, In order to improve the dynamic performance of the DTC system of the asynchronous motor, a direct torque control system is put forward. It uses space vector analysis method to calculate electromagnetic torque and stator flux linkage of asynchronous motor directly, follows the change of the stator flux linkage and torque, omits the complicated calculation, reduces the dependence on motor parameters. The simulation model of the DTC system of the asynchronous motor was established using SIMULINK software package. The feasibility of method is proved in theory, The results of simulation show that the modeling and simulation of the system has good static and dynamic performance, control precision of the system is higher, the stability is better.

Aiming at detecting sea targets efficiently, an approach using optical remote sensing data based on co-training model is proposed. Firstly, using size, texture, shape, moment invariants features and ratio codes, feature extraction is realized. Secondly, based on rough set theory, the common discernibility degree is used to select valid recognition features automatically. Finally, a co-training model for classification is introduced. Firstly, two diverse ruducts are generated, and then the model employs them to train two base classifiers on labeled dada, and makes two base classifiers teach each other on unlabeled data to boot their performance iteratively. Experimental results show the proposed approach can get better performance than K-Nearest Neighbor (KNN), Support Vector Machines (SVM), traditional hierarchical discriminant regression (HDR).

Landing mats are essential for the safe completion of landing impact in gymnastics. Shock absorption and stability during landing impact is provided by both gymnasts’ ability and mat properties. The aim is to determine the influence of different characteristics of mat on mat-ground reaction forces. A subject-specific model with 12 segments rigid body and a model about landing mat in floor exercise were developed by computer simulation. The stiffness and dampness of landing mat influenced the peak of vertical ground reaction force and time to peak, but there were significant correlations between the friction of landing mat and the peak of horizontal ground reaction force and time to peak.

According to the structure and construction characteristics of PC continuous beam bridge and combined with the construction monitoring method of continuous beam bridge, this paper introduces the girder stress strain test technology and method of prestressed concrete continuous box girder bridge, also analyzes the various factors which affect the stress test. After monitoring LinGang big bridge, draw the conclusion through the analysis of its stress and strain.

This paper bases on Petri net theory and related technologies, and establishes Petri net model for warehouse management system, which not only verifies the correctness of the model but also uses Petri net analysis method to analyze the model, lays the foundation of information platform configuration and development.

With the development of information communication technology (ICT), World Heritage Site becomes rely on ICT to manage tourist and resource. This paper examines the concept of ICT and how it could be applied to World Heritage Sites (WHS). This paper also presents the uses of ICT at heritage sites and determines the extent to which ICT can be applied to WHS.

GengYuHe bridge was a prestressed concrete continuous box girder bridge,based on the static load test of single beam bridges compared with theoretical calculation value,check whether the actual control section stress of the bridge are in conformity with the design requirements,and give advice.

Considering the tools, technologies and channels are driving significant change in customer behavior, the paper focus on how destinations are currently using them. Then the paper discusses the key challenges facing destination branding – content, socialization, integration, and measurement. At last, the paper considers what this means for destination brands, the DMO website and digital marketing strategy.

The forecast of natural gas load is a comprehensive and difficult job. In this paper, the gas load forecasting with analysis of environmental resources based on gray model is discussed. The load data of some city from 2002 to 2011 is considered. The different experiments are finished to validate the method. From the experiments, it can be conclude that the gray forecasting model is suitable to short term forecasting. In addition, it can also be found that the oldest data has little influence on the future forecasting data.

In this paper, we give a short survey and analysis on natural gas load forecasting technology using artificial neural network. Different input variables are used to compare the result of forecasting the short term gas load. The experiment results show that the BP neural network can be used to find the implicit relation among historical gas load, weather condition and the future gas load. We also conclude that the input variables have no important influence on the accurate forecast.

Logistics park informatization is the general development trend of logistics park, this paper attempts to :combine logistic park's business model with informatization, construct a new logistics park innovative profit mode, put internet of things fusion in the entire process of logistics park construction and operation, create new informatization operation platform.

The double-acting air-oil intensifier designed in this paper can continuously output high pressure oil which meets the requirements of equipment that is high-pressure and with recirculation motion and it is driven by pneumatic substituting the independent hydraulic power source driven by electric motor. It consists of twin roller piston air cylinder, force amplifier, hydraulic cylinder and oil supercharger. The piston of air cylinder propelled by pressure gas makes cyclic motion and the driving force of piston increased by force amplifier pushes the piston of hydraulic cylinder and forces out hydraulic oil, then oil is input to the system after the second time when pressure amplification by oil superchargers. It has many advantages such as higher pressure ratio, compact structure, high efficiency, low cost and easy access to regulate pressure and flow rate.

The subway is the major means of transportation in Beijing, and it also takes huge energy consumption. Now the consumption of a subway station is 9500 kWh every day, and the proportion of the air-conditioning system energy dissipation is about 64%, in which, a big part of that can be saved down to save and make full use of the energy. The key to the air-conditioning system energy saving is to put forward reasonable energy-saving schemes and feasible method. In this paper, with a subway station in Beijing as a test location，the measurement and data analysis are carried out, and the schemes put forward for energy conservation and emission reduction in subway air- conditioning system.

In this paper, we give a short survey on natural gas load forecasting technology. Because the variation of gas load is influenced by weather and people activity, the traditional forecasting results and the precision is low. The forecasting methods based on statistical learning theory and artificial neural network are discussed in detail. We also give some future research on the forecasting method of gas load.

Ethylenediamine (EDA) functionalized mesoporous MCM-41 particles displaying various functionalization levels have been prepared by one-pot method. The prepared samples were treated with Fe(III) to form cationic complexes inside MCM-41 pores (MCM-41-NN-Fe-x%, x=10, 20 and 30) for trapping phosphate from water. The prepared adsorbents were characterized by XRD, BET, TGA and elemental analysis, and their phosphate adsorption performances were studied. The results showed that the phosphate removal rate of all the prepared adsorbents were higher than 95% at the initial phosphate concentration of 2 ppm. Additionally, the Langmuir model was used to simulate the sorption equilibrium, and the results indicated that the experiment data agreed well with the Langmuir model. The maximum adsorption capacities calculated from the Langmuir model increased with the increase of diamino loadings in adsorbents, and the maximum adsorption capacities of MCM-41-NN-Fe-30% was 52.5 mg/g.

The goal of this paper is instructing the freezing construction scheme of alluvium of wind well in a mine. Through making scheme, designing cooling system and in-situ measuring frozen wall, succeed experiences of passing the expanded clay seam smoothly were achieved. It is hoped that the practical experiences will be reference to constructing mine in the analogous ground.

This article analyzes the form of carbon discharge within the building life cycle, and indicates the relationship between energy saving and carbon reduction. It puts forward that when selecting the cooling and heating source, we should define the strength standard and assessment index of carbon discharge. While we weigh the energy rationality, low carbon charge should be taken into consideration, in order to reduce the CO2 discharge in buildings.

In this paper, we propose algorithm based reinforcement learning for spiking neural networks. The algorithm simulates biological adaptability and uses the soft-reward from environment to modulate the synaptic weight, which combines spike-timing-dependent plasticity (STDP), winner-take-all mechanism. The algorithm is tested to classify a number of standard benchmark dataset. The obtained results show the effectiveness of the proposed algorithm.

Mechanical parameter analysis is a complicated issue since it is influenced by many factors. Closely related with the influencing factors of compressibility coefficients of rock material (sandstone), this article first introduces the way to process partial least square regression (PLSR) analysis. The process of carrying out PLSR is divided into six steps as for analysis and prediction of the regression model, which are data preparation, principle collection, regression model for first principle component, secondary principle analysis, establishment of final regression model and number determination of principal component l. And then introduces PLSR for application of analysis and prediction of compressibility coefficients with 30 experiment samples. Seven prediction samples are carried out by PLSR with the training process of 30 samples. The result shows PLSR has good accuracy in prediction under the condition that the model is properly deprived based on certain experimental samples. Finally, some conclusions are made for further study on both mechanical parameters and partial least square regression method.

Based on emerging issues and new trends in the production safety work, This paper will reveals the characteristics of production safety accidents and laws, and explores the monitoring method of safe production run, and provides better basis of decision making for the safe production conditions can be effectively controlled.

The design of pressurized components at elevated temperature is limited by available mechanical properties that often do not span appropriate range of stress, time, strain and temperature. To improve the design process, a new approach based on short-time stress relaxation test (SRT) is introduced in steel tensile creep analysis. The experiments are implemented using SRT and tested for creep properties of 12Cr1MoVG steel at 560 °C. The results of creep curves agree well with the traditional constant load creep test data. The possibility to apply SRT approach is shown promising in the design of the pressurized component at elevated temperature.

Y-branch is often used in connection between a main pipe and two branch pipes, for example, in furnace, quench boiler, nuclear parts and so on. The stress distribution in the Y-branch is very complicated because of complicated shape and complex loads on it. The stresses in the Y-branches cannot be determined by theoretical equations. Finite element method is used to analyze the stresses in the Y-branches. As an example, a Y-branch used in a high temperature furnace is calculated with ANSYS software. The temperature distribution and elastic and elastic-plastic stress fields in the Y-branch under mechanical and thermal loads are calculated. Strength, creep and fatigue of the Y-branch are evaluated based on T-1300, T-1400 of ASME Boiler and Pressure Vessel code Sec Ⅲ Div 1 Subsection NH.