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For studied the rule of wind turbine output characteristic in condition of variable wind. The paper set up a wind model for a wind farm and a simulation model of 1.5MW wind turbine. Choose two control tactics which called voltage control and reactive power control to do the simulation and test. The result shows that took reactive power control at normal operation, the turbine get a well performance. If fault happened, choose voltage control was reasonable. So it provide reference for turbine operation.

It’s difficult to describe the 3d geometry and to establish the 3d model of tower equipment in OpenGL. High-level command functions to define complex three-dimensional modeling is not provided in OpenGL. This paper introduces 3d model of the tower equipment how to display dynamically in OpenGL. Interface of OpenGL import 3d model is description in detailed. Storaging format and reading file of STL (Stereo Lithography) are elaborated. How to build the 3d model is descripted. When tower equipment displayed dynamically, what is the key step to establish the model of tower equipment. The dynamic model of the whole tower equipment is displayed, in order to see clearly the structure of tower equipment.

Elliptical head is an important standard part of the separation tower equipment. It can not be generated by tensile method, rotation method, because the rotation axis can not pass region. This paper introduces the ObjectARX programming environment. It describes how to build the menu and the dialog box. ObjectARX is a secondary development tool of AutoCAD. With its function and its mechanical drawing once learned, four arcs of ellipse can be used to build 3d modeling of head.of tower equipment. The ObjectARX programming technology is applied to develop AutoCAD, making it more convenient to darw the professional 3d graphics.

This paper introduces the basic principle of phase code pulse compression technology, the characteristics of phase coded pulse compression system, and the technical approach of radar to implement phase code pulse compression.

Herein, a novel fuzzy PID temperature control system was proposed based on the technological process and control requirement of the crystal annealing furnace. Simultaneously, the electric control system was also designed with SIEMENS S7-300 PLC as the master controller. The results indicated that the system has the merit of rapid response time, low temperature fluctuation and all of the test items could meet the requirement of the actual utilization.

In this paper, a novel cooperation space-time network coding (CSTNC) scheme based on multi-sources distributed cooperative network is considered. In this scheme, multiple sources transmit signals to relay and destination node. The relay re-encodes the decoded signals through space-time network coding with the aid of multiple antennas. The simulation shows that the BER, capacity and outage probability of the CSTNC becomes better with the increasing of relay antenna number and very close to traditional space-time network coding (TCSTC) scheme. Meanwhile, transmission efficiency analysis demonstrates that CSTNC scheme has higher transmission rate.

In order to deal with subway emergency, the paper builds the emergency drill system based on scenario analysis for the security of persons and property within the subway. By participating in the drill system, make sure that units and division involved in the rescue and command system learn their responsibilities by heart under emergency, enhancing collaboration of various departments, improving the efficiency of emergency rescue, thus the rescue can be conducted orderly. This paper introduces the concept of subway emergency, emergency management and organization and the drill system.

This paper presents an algorithm about key management including key generation and key recovery in cryptosystem based on fingerprint and fuzzy decision. Traditional key for the encryption and decryption is remembered by a trusted person, or stored in a safety location. The key may be lost or misused for the person’s self-ish desire. Sharing secret algorithm is used to prevent from misusing in a single management, and fuzzy vault scheme is used to avoid the disadvantage of numerical password. But the proposed method is not an easy combination of fuzzy vault and sharing secret. To keep from the collusion among some persons, a simple fuzzy decision is added in the proposed method. Security analysis and experimental results are given to show the proposed algorithm is feasible and safe for key management in cryptosystem.

Subway train positioning technology is one of the key technologies, however when red band appears in dispatch center, train ground communication fails and other issues, you need a back-up emergency systems to provide train position information for the station dispatchers in order to arrange train route. This paper describes a back-up system for positioning subway trains. The system is a combination of vehicle and ground subway train assisted positioning system, it can fast and accurate get the location information of subway trains, to provide protection of safe and efficient operation for the subway trains.

Through the relations among the torpedo velocity at tube outlet, cylinder volume, cylinder pressure and emission valve size, we adopt the projection pursuit regression method and establish the model to predict the torpedo velocity at tube outlet. Through the comparison of experiment data and model prediction, fitting accuracy of this relation model is stronger and the projection pursuit regression is an efficient method which can research the initial ballistic trajectory of ship-launched torpedoes.

In the computer vision, feature extraction is an important research orientation. Corner and edge detection is a basic technique for obtaining local feature in this image. In the paper, we propose a method that corner and edge of image is detected simultaneously by an annealed chaotic competitive network. The method is compared with several traditional methods of corner and edge detection algorithm, the experiment result shows a good performance. The clustering method can achieve the corner and edge detection simultaneously.

Introduced one ultrasonic ranging alarm device based on SN8P2501B microcomputer, it mainly included ultrasonic emission circuit, receiving circuit, keyboard, alarm circuit and the software. Compared with the traditional ranging methods, the system used 555 time-base circuit to produce ultrasonic, and designed a temperature compensation circuit to eliminate effect of sound velocity produced by the environment temperature. The practical application results show that the ranging system is stable , reliable and highly accurate, so the technology and methods adopted in the system are highly practical and worthy of being used abroad.

This paper focuses on the current development of military aircraft safety risk decision method is not enough application of projection pursuit method to calculate the weights of the evaluation indexes of a military aviation, comprehensive evaluation of different layout scheme. The available schemes were quickly ranked by their safety performance, the difficult problem with safety design of military aircrafts was primarily solved in the aeronautic project.

The effect of Nd on the mechanical properties of magnesium alloy AZ91 has been studied. The results show that the addition of 1wt.%Nd can refine the grain size, cause the formation of high melting point Al2Nd phase and reduce the amount of β-Mg17Al12 phase. and enhance the mechanical properties of magnesium alloy AZ91 at room temperature and 150°C.

The microstructure and mechanical properties of Mg-9Gd-2Y-1Sm-0.5Zr alloy have been studied by micro-analysis and tensile tests. The results showed that the alloy mainly consists of α-Mg matrix, Mg5Gd and Mg24Y5. With the increase of temperature, the tensile strength of the alloy increases at first and then decreases, and the peak appears at 250°C.

As an important module of enterprise device management, spare parts inventory affects other strategies like equipment maintenance, overhauling, repairing etc. Furthermore, the normal production of enterprises and economic benefits are closely related with it. In this paper, spare parts are classified based equipment maintenance features [. After analyzing the dynamic and uncertain demand context, a probability inventory model which takes equipment downtime loss into account is presented [. A reasonable inventory costs is suggested through a lot of computing. The model and methodology have been demonstrated by a case study.

The traditional CAPP system pays much attention to the intelligent generation of the parts process route or pursuit integration of CAD and CAPP and CAM, but it has exposed many shortcomings in the process management of process design and approval. In order to solve the problem of information transmission and process reengineering, this paper discusses the application of work flow technology in the CAPP system, and analyzes the process design and approval process based on Petri Nets model, and finally explains database design and realization of process workflow and the control mechanism of workflow engine based on state transition on emphases. Through the practical application, the system can greatly improve the efficiency of design and management of process, the process design is more flexible and more standardization.

The high pressure die casting (HPDC) process of an ADC12 aluminum alloy auto part is researched by the software ProCAST and FLOW-3D, respectively. The possible HPDC defects of the auto part are analyzed. The difference of the filling process with the same technological parameter is studied. Compared with the simulation result of ProCAST, FLOW-3D software simulation result is closer to the die casting of the actual production.

Wavelet Neural Network (WNN) is a new form of neural network combined with the wavelet theory and artificial neural network. The wavelet neural network model based on Morlet wavelet and the corresponding learning algorithm were studied in this paper. And through learning the wavelet neural network model is applied to all kinds of engineering examples, it proved that the wavelet neural network prediction model which has a more flexible and efficient function approximation ability and strong fault tolerance, and with high predicting precision.

Cloud computing with its powerful feature has been used preliminary in some commercial areas in the world, cloud computing also is used in IT industry, and it is a new revolution in IT industry. Cloud computing is of great concerned for its characteristics of the security and reliability of data mass storages and the low requirement on the customer premise equipment, especially in the financial industry. This paper describes the basic concept, characteristics and development status of cloud computing, and on the basis, the application of cloud computing in the banking industry is discussed, and the possible problems are pointed out.

Fresh vegetable logistics is an important part of agricultural product logistics in our country, but the unique characteristics of fresh vegetables, fresh time for vegetable logistics requirements is strong. therefore, the logistics mode selection of fresh vegetables is particularly important, several modes of vegetable logistics,are analyzed in detail in this paper, and provide some reference for the fresh vegetable logistics mode select.