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Wind power is widely used as a type of clean and renewable energy source in recent years. However, large-scale wind power penetration brings lots of challenges due to the uncertainty of wind speed. As a result, the research of wind speed uncertainty plays an important role in large scale wind power integration. In this paper, the multi-scale amplitude modulation effect of wind speed random fluctuation is found based on actual wind speed data. And the physical mechanism of multi-scale characteristics are presented from the perspective of turbulence. This research has both certain physical academic meaning and engineering application value in wind speed uncertainty research.

In order to describe the generalization ability, this paper discusses the error analysis of neural network with multiply neurons using rational spline weight functions. We use the cubic numerator polynomial and linear denominator polynomial as the rational splines for weight functions. We derive the error formula for approximation, the results can be used to algorithms for training neural networks.

In order to extract useful information of underwater acoustic signals from noise, preprocessing steps are unavoidable. In view of trend and transient pulse interference exited in the original data inevitability, morphological filter method is applied and analyzed in this paper. Data processing results show that the morphological filter method is superior to the traditional filter method.

Profile control and flooding technique is an effective way to enhance the oil recovery of low permeability reservoir.Analyzing the relation between oil and water interface and determining injection volume under different concentration is the key to success in profile controlling and flooding in low permeability reservoir .The research is about SJT-B collosol of physicochemical property under normal pressure and temperature.We also carry on the study on measuring SJT-B collosol interfacial tension for a long time under different concentration.Besides, we conduct the plugging degree experiment by injecting SJT-B collosol with the concentration of 0.8% in different permeability core.The lower the core permeability, the higher the plugging degree. By optimizing the injection pattern we conduct the three-tube parallel profile control and flooding experiment in the low permeability heterogeneous core.It indicates that SJT-B collosol mainly access to high permeability layer and have an effective plugging effect .The absorbed liquid rate of medium permeability layer is increased apparently ,while low permeability layer is increased slightly.The SJT-B collosol of injection method has efficient effect on enhancing the oil recovery of low permeability reservoir in late water flooding.

In this paper, a new visible light communication system is proposed replacing signal lamp system on the boat. The new visible light communication system is demonstrated in 50m including RGB LEDs, lens and large area photodiodes. 153.6kbit/s data rate is achieved with infrared codes.

This paper introduces the method of porous ZnO microspheres by sodium citrate assisted hydrothermal synthesis with a mild, economy: first, basic synthesis globose precursor of Zinc Carbonate Hydroxide, then followed by thermal decompose the precursor to obtain porous Zinc Oxide microspheres. The morphology and structure of the precursor and synthesized porous microspheres were characterize by a series of methods, and did a series of experiments by changing dosage and reaction time of the sodium citrate and urea, finally the paper discussed the formation mechanism of porous ZnO microspheres.

In order to improve the virtual flux oriented vector control performance of PWM rectifier, an improved observation method of virtual flux-linkage is proposed. To avoid the relevant problems of pure integrator, and to achieve the accurate observation of the grid voltage’s phase, three first order low-pass filters are cascaded to displace the pure integrator. Based on the SVPWM modulation module and the presented algorithm, grid voltage sensorless control system of three-phase PWM rectifier is given. Simulation results have shown that: either in rectifying or inverting status, the amplitude and phase of virtual flux-linkage can be observed accurately, i.e. the control system of PWM rectifier can operate reliably without the grid voltage sensors; the presented estimation method of virtual flux-linkage is effective.

The photodegradation of 4,4-bis (4-hydroxyphenyl) pentanoic acid (DPA) with two cyclodextrins (α-CD and β-CD ) in aqueous solutions induced by UV-light was studied in this paper by means of fluorescence spectra and high efficiency liquid chromatography. The result suggested that DPA with α-CD or β-CD formed inclusion compound in aqueous solutions. The photodegradation of DPA with two cyclodextrins or without cyclodextrin was pseudo-first order reaction. The photodegradation of DPA was accelerated by the addition of β-CD in aqueous solutions, but the that of DPA was inhibited in case of adding α-CD. These differences were due to the differences in inclusion interaction of DPA with α-CD or β-CD.

Introduced based on RFID, GPS, GPRS technology, logistics tracking system. The system uses a combination of GPRS data transmission PC monitor management , the use of low-power control chip STM32F103RBT fusion technology GPS technology , GPRS and ARM , and other industrial areas , to achieve the objects of the logistics chain in real-time tracking , logistics links ensure that items do not lost and replaced.

The paper proposed a design scheme of wireless sensor network border router based on IPv6. Project mainly expounds the realization of hardware and software design of boundary router, focuses on wireless sensor network IPv6 protocol stack adaptation layer design based on. Through the data packet fragmentation and reassembly mechanism as well as the header compression scheme, adaptation layer of protocol stack to achieve the transmission of IPv6 data packet in the IEEE in 802.15.4 link. The experimental results show that, this scheme realizes the seamless integration of wireless sensor network and IPv6 network, data transmission is reliable, practical application value.

In this paper, a home wireless network platform based on Zigbee technology. This article analyzes the Zigbee network protocol, discusses the key issues to build a home wireless network using the Zigbee technology. The network topology, network routing algorithms and network sampling strategies and other issues were discussed and proposed solutions by building a home wireless network monitoring experiments on the pulse signal. The results showed that based on Zigbee technology to build a home wireless network is feasible, the wireless network in the home monitoring has broad application prospects.

UHF radio frequency identification system with write speeds, large storage capacity , recognition distance and simultaneously read multiple tags , etc. , has been more widely used in logistics. Introduced in line with ISO 18000-6 standard UHF RFID tag main characteristics, structure, working principle and write methods, proposed the corresponding reader solutions, focusing on the reader hardware design and software program flow. The application results show that the reader read and write speed (single tag 64bit / 6ms), recognition rate, recognition distance (≥ 4m).

ZigBee technology is a small disadvantage of network coverage, this article will introduce GPRS wide-area wireless communication technology ZigBee network, ZigBee network to build a remote data collection and management system, and use intuitive embedded Web server to improve management efficiency. System test results prove that the system has good validity and reliability.

The phase spectrum time delay estimation (TDE) method is being used widely in trajectory tracking and target location, which due to its superiority in computation load and accuracy. However, the precision of TDE had declined severely as the result of noise. This paper plans to analyze the factor of noise, which has effects on the performance of phase spectrum TDE algorithm based on the difference principle. Theoretical analysis and computer simulation show that the fluctuation of phase caused by noise leads to poor performance. Furthermore, the extent of the influence relates to the time delay and signal frequency.

In this paper, cross metal patches are inserted inside the conventional rectangular microstrip antenna, and thus it can work at two frequencies. The finite difference time domain (FDTD) method is selected to study effect of this left-handed metamaterial with near-zero-index of refraction. Compared with conventional rectangular microstrip antenna, effect of near-zero-index from positive and negative on conventional rectangular microstrip antenna are studied. Simulation results show this antenna works at two frequencies. Compared with conventional microstrip antenna, near-zero-index can improve antenna’s gain obviously.

The Smart Hybrid Powerpack (SHP) is an electro-hydraulic system which combines the system of Electro Hydraulic Actuator (EHA) and advanced technologies such as network fault tolerance and intelligent control. EHA system has been famous in the industry because that the EHA acts as a power-shift which shifts the power from high-speed electric motor to the high-force of hydraulic cylinder by bi-directional piston pump. If errors in the plant and network occur in the SHP, the system will cause serious malfunctions. To reduce plant noises and network errors, this paper shows the intelligent control method comparing Self-tuning fuzzy with fuzzy control and network fault tolerant error control coding in the SHP. In the intelligent control part, the simulation result shows good performance to reduce plant noises by the self-tuning fuzzy than fuzzy control. In the network fault tolerant error control coding part, proposed scheme also shows good performance by CRC code and Reed-Solomon (R-S) code in two channel (CRT) method than one channel only. We developed LabVIEW Graphic User Interface (GUI) to show these simulation results. Using this GUI, we can save time to experiment and get benefit of guidance to make real program.

Before image feature detection and recognition, image enhancement can highlight the main people or things and their details from foreground, and also can suppress the useless information from background effectively. An algorithm model of adaptive image generalized fuzzy enhancement is established. For all aspects of the algorithm model, a variety of computing forms are put forward, and the evaluation standard of image quality is defined. The principle of algorithm is to achieve space transform between image gray space and generalized fuzzy space using generalized membership transform and its adverse transform. In the process of space transform, the contrast among successive region for space of generalized fuzzy membership grade is enhanced by generalized fuzzy enhancement function. Enhanced images are evaluated by quality standard, and the optimal values of adjustable parameters of membership grade transformation function and the fuzzy enhancement function are selected adaptively based on the optimal quality. Then, the enhanced image with best quality can be obtained. Experiments show that the extracted contour of enhanced image is structured, weak-edge-highlighting, and rich-detail.

The Technology System of Systems (TSoS) studies the technologies, as well as the connections among these technologies which were derived from the capabilities requirements and systems requirements. The TSoS related Concepts and studies are introduced. A methodology to the generation and assessment to TSoS is proposed. The generation of TSoS is based on the characteristics of different technologies and corresponding capabilities/systems requirements. The assessment of TSoS is divided as the readiness assessment and the satisfaction assessment. Only the satisfaction assessment is concerned in this study. The TSoS satisfactions assessment studies how well certain technologies can satisfy varied TSoS requirements. A case is studied to validate the efficiency of the proposed methodology using sixty technologies derived from the US weapon acquisition report for the 2012 fiscal year.

An improved Grey Target (GT) approach using the Evidential Reasoning (ER) algorithm, named as ER-GT, is proposed to handle the challenge when conducting the contribution analysis in the Weapon System of Systems (WSoS) context. The WSoS technology contribution analysis is a small-sample, less-data problem without a recognized pattern, which fits the characteristics of the problems that GT is designed to solve. However, the standard system in GT may not exist at all since its indices are derived from different systems and fails to be consistent with the System Military Value (SMV), which represents the contribution made of a system to WSoS. In order to make certain adjustments of the standard system, the information derived from capabilities requirements, practical restraints and/or experts’ knowledge must be taken into consideration. Since the ER algorithm has a privilege in dealing with different types of information under uncertainty, it is applied to transform the standard system into a “mission system” so as to integrate different types of information. A comparative case using both GT and ER-GT is studied to validate the efficiency of the proposed ER-GT approach. The study result shows that the defense capability is given a bigger contribution rate, which has been neglected by traditional GT.

Warping and distortion in plastic parts has been a serious problem in mold-injection.Traditional solution is to first produce a mold and then test the moldrepeatedly. By employing Moldflow, it can be easily to offer a precise analysisand prediction of warping in products. Meanwhile, the results can be used toadjust the designed structure and process conditions of the mold. Finally, themold and its products are optimized.

A novel low phase noise LC Voltage Controlled Oscillator (LC-VCO) is designed in standard 0.18μm CMOS technology. Instead of common NMOS cross-pairs for a conventional complementary LC VCO, both body-biasing and Q-enhancement techniques are employed to provide a larger negative resistance for the VCO. Post-layout simulations showed that it can oscillate at a frequency range of 4.34-4.73GHz, and comsume a supply current of 1.52mA from a supply voltage of 1.8V. The VCO achieves a phase noise of -132.8dBc/Hz @ 1MHz offset and a figure of merit (FOM) of -195.9dBc/Hz at the frequency of 4.5GHz. A die area of 475μm×498.6μm is occupied.

Sigma-Delta (∑∆) modulators are commonly used in high-resolution analog-to-digital converters (ADCs). In this paper, a high-performance modulator targeted for ultra-high-frequency (UHF) radio-frequency identification (RFID) zero-intermediate frequency (ZIF) receivers is designed in standard 0.18μm CMOS technology. The modulator has been designed with switched-capacitor (SC) integrators employing gain-boosted operational amplifiers, voltage comparators and nonoverlapping clock generators to satisfy such requirements as high gain, low voltage and wide bandwidth. The behavioral-level modeling and circuit-level design are carried out with MATLAB/Simulink and Cadence/SpectreRF, respectively. Ultimately, the high-speed and low-power realization of a second-order single-bit modulator with an oversampling ratio (OSR) of 32 is presented. Simulation results shown that, from a 1.8V supply, operated at a sampling frequency of 64MHz, a dynamic range of 53.4dB over a signal bandwidth of 1MHz is achieved.

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.

Focus on equipment maintenance support informationization basic requirements, this paper introduced certain ordnance equipment maintenance support system based on B/S structure , carried on preliminary discussion on design of equipment integrated support system, gave a preliminary analysis and research on design ideas, system structure and function, auxiliary module.

Repair and technical support ability of equipment are important factor restricting the persistent state of combat power. Along with the increase of service life of a certain type ordnance equipment, equipment performance become degradation, reliability decreases, failure rate increase.The purpose of this paper is to study the mechanism of failure, find out the fault rule, expert's experience with fault tree reasoning and neural network fault diagnosis technology being applied to the fault diagnosis, aiming to solve the difficult fault, shorten the repair time, improve the ability of technical support.

For maintenance and support needs of a certain type of equipment, the detection on hydraulic of a certain type equipment Based on C8051F020 as the main control chip was designed. The equipment flexible applies to all port resources of C8051F020, it realized port power control,self-test / measurement controlled driver, LED driver,buzzer driver, solenoid valves driver and rack motor driver via I/O interface, it realized operational process control and display testing results via level conversion chip of SP3223E ,It realized operation training, principles assisted teaching and fault repair in-one simulation training.

Based on the AHP and TFN, this paper establishes the indicator system, and develop the strategic framework using the fuzzy Delphi method. Then the triangular fuzzy number model is established using Fuzzy Analytic Hierarchy Process, and the key factors influencing agricultural industry are extracted. The manufacturers and government decision-making body can use this as the basis, to promote the development of the agricultural industry.

Through in-depth understanding of the domain knowledge of insurance and the study of the technology of data warehouse, the paper illustrate the application of data mining technology and data warehouse technology in the insurance clients analysis, and from the basic flow of, discusse the application of data warehouse technology in the field of insurance industry. Then, from the concept of data warehouse, describe the design and implementation of data warehouse concept model and logical model.

This paper mainly uses ANSYS, the finite element analysis software, to make nonlinear analysis of reinforced concrete beam. The model simulating the test process was established, the calculation results of ANSYS are compared with the experimental results. The comparison shows that ANSYS analysis results are similar to experimental results, which indicates ANSYS analysis software can be used to simulate the mechanical property of reinforced concrete structures.

Our research was conducted based on the development of some antitank missile CCD observer test system. Combining the function and working principal of a typical CCD observer, we undertook an in-depth study on the collection of the core output signal of the CCD observer, naming the video signal information, and the design of key software and hardware. Utilizing both digital and video collection technology, our study provides handling method of measuring angle precision, interference rejection as well as sensitivity. Using the most advanced technology, this system is characterized with a user-friendly interface, analytical visualization, and reliability.

Using simulator for the weapon and equipment operation training is the equipment development trend, this paper introduce one equipment command system simulator design idea, function and work way, analyze the hardware composition and software design, realizing the function simulation of the equipment command system,getting successful application to the equipment training.

Describes the background and qualitative simulation theory development, then describes the qualitative simulation and application of fault detection, fault detection Finally, qualitative simulation development are discussed. In order to deal with this kind of challenge, appear a series of system fault detection and diagnosis technology, including qualitative simulation technology is one of the important technical one. Through the Qualitative Simulation theory QSIM (Qualitative Simulation) related theory analysis and of the technology in fault detection field operation of the process of research, analysis found that the technology in the field of FDD advantages and disadvantages, in view of the existing shortage, it gives a fuzzy set theory and similarity principle on the make, theoretically perfect this model, and the detection and diagnosis research form an effective guidance.

Based on virtual instrument development idea, one equipment emission system fault diagnosis device is successfully developed, with the characteristics of strong practicability, compatibility and scalability. The successful application of virtual instrument technology has shorten development cycle, reduced project cost, decreased the testing time, simplified the testing process, realized the automation and intelligent of equipment testing process. This paper describes the diagnostic system function, composition and main design method, being of reference value in equipment fault diagnosis field.

to hold the merits of the traditional hysteresis controller, and at the same time, hold back the change of switching frequency and reduce the switching power loss in hysteresis control of PWM rectifier, based on the relationship between line currents and switching status, an improved algorithm of double-hysteresis current control method for three-phase voltage-type PWM converter was proposed. In the strategy, the position of reference voltage vector can be detected by double hysteresis, PLL circuit can detect the output of switching states. The proposed algorithms not only hold the merits of traditional hysteresis, such as quick current response and current limited capacity, but also, it can overcome the drawback of non-fixed switching frequency of traditional hysteresis. The algorithm has been simulated and verified by MATLAB/simulink platform, and the system operates stably.

In this paper, based the actual application condition of domestic and international brake disc for high-speed train, the low-alloy cast steel of the brake disc for high-speed train is developed. The chemical composition, melting and casting processes as well as heat treatment technology of disc material are studied. The new low-alloy cast steel has the ideal metallographic microstructure, proper physical and mechanical properties. The tensile strength is more than 1100Mpa in 20°C condition, the impact energy value (Aku2) is more than 8J in-60°C condition. The test results show the new low-alloy cast steel developed can meet the brake disc performance requirements for 380km/h high-speed train.

It’s necessary to establish a perfect dust water supply system according to Coal mine safety regulations. In order to do researches on the reliability of mine dust water supply network, this paper deduces the similarity number of flow rate and pressure under the condition of abnormal similarity, and establish the physical model of mine water supply network according to the gravity similarity criterion at first in lin-nan mine as the background. Monitor the running status of the whole network, measure the flow rate and pressure of the monitoring stations, and then contrast the experiment result and EPANETH simulation result with the data of the original network. The results show that physical model meets gravity similarity under the condition of abnormal similarity, which provides the experimental basis for the follow-up research on mine water supply network.

With the rapid development of the remote sensing satellite, the size and resolution of remote sensing image grow increasingly. The evaluation of image quality requires precise information of ground control points extracted from remote sensing image and reference image. Therefore, we propose an adaptive Wallis enhancement based on radiation-parameters to increase the number of ground control points and to improve the matching precision. First, feature vectors of sub-region are constructed by computing image radiation-parameters, and then the sub-region terrain in the remote sensing image can be recognized using nearest neighbor classifier. Second, according to specific type of sub-region terrain, we enhance images using adaptive Wallis filter with local parameters. Finally, two-level matching method is used to extract and match the control points. The experiments show that compared with existing Wallis filter which are based on global parameters, our method gets better results in the detail enhancement on ZY-3 image so that more and higher accurate ground control points can be effectively extracted to achieve the evaluation of geometric precision automatically and accurately.

The use of FFmpeg technology, overcome the current media asset management of some defects, better play the role of media assets. In response to various types of video data, audio data, text, pictures, and other media digital data storage, inventory management, query, edit material transcoding, information dissemination, and equipment and fixed assets to conduct a comprehensive management. The results show that, based on the " technology " of mass media resources, is to promote the media industry is the motive power of development, any form of content are the media core assets. The media asset design, solve the media transmission and conversion, the ultimate guarantee of effective and complete data. Keywords Key words: media assets; FFmpeg; transcoding; digital storage

The quantity and damage degree caused by the traffic accidents on trunk highways always take the big part in the highway traffic accidents. Now, there are no more and complete evaluation methods for the trunk highway traffic safety. Whats more, the index system is not perfect. Based on the characters of traffic safety on trunk highways and feasible factors of information collection, this article confirms 3-level evaluation index system for 20 evaluation indexes and the evaluation methods for trunk highway traffic safety based on AHP. Taking Xiake Blvd of Jiangyin City as example, this article analyzes and proves the efficiency and feasibility of these methods. The evaluation results can provide the basis for the improvement of highway traffic safety.

The level of enterprise executive ability has direct correlation with the survival and development of enterprise. According to the particularity of electric power enterprise development and the connotation of executive ability, the paper established a comprehensive multi-level evaluation index system for electric power enterprise executive ability in terms of executive power, executive effectiveness and executive efficiency. Then the paper quantifies the qualitative indicators and introduced the corresponding fuzzy comprehensive evaluation model. At last, the applicability of the comprehensive index system just created was demonstrated by an example calculation about one power supply company.

This paper mainly Study the satellite emergency communication characteristics of reliable data transfer protocol, combined with the UDP protocol and the TCP protocol of the advantages and disadvantages. The article puts forward an improved expanded with reissue of double reliable D-RCUDP protocol. This paper introduces the application background, the hierarchical structure, the core mechanism, application platform and experimental results.

Since soil stabilizer consists of many operating components, it has lots of noise sources, and the major noise sources are relevant. So, it is appropriate to identify the noise source of the soil stabilizer using the partial coherence analysis. In this paper, a multi-input and single-output noise source identification model is firstly established, and then an algorithm is developed for the calculation of the partial coherence function. Finally, an experiment is carried out with an actual soil stabilizer. In the experiment the main noise sources are accurately identified. This work provides some guidance for further study of vibration and noise reduction of the soil stabilizer.

To decrease the computational complexity and improve the performance of channel estimation for underwater acoustic (UWA) sparse multipath channels, a sparse least square (SLS) channel estimation algorithm is proposed. The proposed algorithm combines advantages of both generalized akaike information criterion (GAIC) estimation and estimation using effective order of channel impulse response (CIR). Known pilot data is used to estimate effective order of CIR and then the position of taps of CIR is estimated. In order to adapt to the environment with low SNR and reduce the dimension of signal space, adaptive threshold is also used. Simulation results indicate that the proposed method has good performance of channel estimation and low complexity.

The released and implemented traffic signals are analyzed, and the important content on the application of traffic signals is studied, which can provide help on the scientific establishment of road traffic signals. The related content about the classification, sequence, setting conditions and setting quantity of the road traffic signals is explained in detailed. Two design schemes of right-turning vehicle control mode are proposed. The conversion sequence of traffic signals and setting of crosswalk signals are respectively studied. The Opinions for the next revision is proposed according to the problems in present technique standard.

A new algorithm for the inverse kinematics of a kind of 6R serial robot was introduced. Firstly, the positions of all the joint points are determined with the help of the basic geometric entities, such as sphere, circle, line, plane and so on. Then, the angles of each joint are computed by the inner product between line and line or plane and plane. The proposed algorithm gives a new geometrically intuitive approach for solving the inverse kinematics of the robot.

The post-evaluation about construction process for cogeneration plant project is an important part of post-evaluation, indicating the completion situation of each stage for the project implementation. A post-evaluation model of construction process for cogeneration plant project based on fuzzy soft set was applied in this paper. In terms of six aspects of construction process, score these indexes for each cogeneration plant with interval value in the form of tabular, and then sort the construction process effect of these power plants. The proposed model contributes to reflecting the ambiguity and arbitrariness of the evaluation about construction process, so as to provide scientific and effective information for the decision-making of the construction of cogeneration plants in the future.

This paper study a discontinuum model on the rock mass, which represented by an assembly of jointed elements and a fracture is initiated when the stress in the joint between two elements exceeds a critical value. The rock fracture mechanics model in this paper show that the continuum damage mechanics is based on the fact that the brittle rock has pre-existing defects, and the material failure is a process of growth and nucleation of these defects.

Equal channel angular extrusion (ECAE) is a process used to introduce severe plastic deformations (SPD) to processed materials with the aim of improving their mechanical properties by reducing the grain size. In order to investigate the effect of die angle on stress and strain produced by ECAE, a new die was designed and the finite element analysis (FEA) was carried out to simulate the ECAE process. The new die is comprised of one internal mold, two external molds and one pressure rod. The main advantage of new die is it can be used for different die angle wihout changing the external mold. As a reult, the new die design reduces the tool cost and improve the ECAE process efficiency. The FEA results show that shear deformation occurred during ECAE, and the maximum effective strain was about 1.669 locating at bottom of the workpiece.

In order to test the correctness of modification parameters, this paper designs respectively test schemes to measure transmission error and geometric rotary error in accordance with the performance requirements of the FA cycloid-pin gear planetary drive reducer. And we design the drive chain connecting parts which accord to the physical size of this prototype. Then the two tests have been done to prove the correctness of the theory.