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Stiffened Thin Wall Panel Structure is a widely used structural configuration in the design of aircraft’s inlet duct and large open bay. Vibration fatigue failure of stiffened panel structure will quickly emerges under strong broadband random loading environment which caused by shock waves moving at the inlet lip and cavity vortex and shear layer oscillation during flight. At present, a main research focus on dynamic strength design of aircraft’s light-weight structure is to reduce the dynamic stress response level in broadband random vibration environment ,so as to improve the ability of thin wall panel’s vibration fatigue property with light structure weight. Taking a stiffened thin panel of inlet duct as a typical case under random vibration excitation environment, an Advanced dynamical topology optimization methods is established based on the parametric modeling technique . Within the main frequency domain of external dynamic load, the maximum root mean square of stress (MRMSS) for global element of stiffened panel structure is calculated and optimized under the weight constraint with Genetic Optimization Algorithm (GOA). The comparison of structural stress response before and after optimization design shows that the maximum element RMS dynamic stress is reduced by 38% with the weight increased by about 9.8% and the purpose of improving vibration fatigue property is reached.

Clustering analysis plays an important role in scientific research and commercial application. K-means algorithm is a widely used partition method in clustering. in this method.The number of clusters is predefined and the technique is highly dependent off the initial identification of elements that represent the clusters well. As the dataset’s scale increases rapidly, it is difficult to use K-means and deal with massive data. partitions.To prevent this problem,refining initial points algorithm provided.it can reduce execution time and improve solutions for large data by setting the refinement of initial conditions.The experiments demonstrate that sample-based K-means is more stable and more accurate.

The shortcomings of current on-line condition monitoring system include: the research was concentrated in AC substation; the function was single and completely independent; the protocols were not compatible and the interface was not unified. To improve these disadvantages and better satisfy the needs of the condition monitoring in converter station, the design and implementation of condition monitoring and decision support system in HVDC converter station was realized. By studying of condition monitoring method, decision support technology and engineering application of HVDC project, the system design principle was discussed, the software structure was shown and the function realization was given in detail. The implementation realized real time monitoring for running equipments, provided reliable gist for maintenance and reduced the costs of resources. The implementation is applied to HVDC project witch has a great significance in improving the operation efficiency and promoting the smart grid construction.

Adsorption is proposed as an effective method for phosphate removal in real seawater with low phosphate concentration. This paper aimed to investigate the capacity of chitosan and iron hydroxide flocs for phosphate adsorption in real seawater, and the results shown iron hydroxide flocs had better performance of phosphate adsorption than chitosan.

Now dispatch centers needs to do a lot of work configuration and spend a lot of time to debug to communicate with substations. This is not only time-consuming but also error prone, so the alarm information needs to be directly sent. This paper presents the design and implementation of Alarm information directly transfers system, gives the system structure and software architecture of AIDT system used in UHVDC project; getting SOE based on distributed component Ice, realizing the protocol based on finite-state machine. And combined with the actual example, this paper provides a detailed explanation of the message. The program can be running on multiple operating systems including Debian Linux, KyLinux, HPUX and so on. Successful interoperability experiments proved that this system has good consistency, and running a long time in actual project proves the stability and reliability of the system. This system not only satisfies the need of UHVDC, but also has guiding significance on the research of AIDT system in UHVDC project.

This article describes the basic meaning, features and foreign developments of the MEMS-IMU and the RF-MEMS technology, presents and analyzes the research and the actual application of the MEMS technology in missile guidance, navigation, data link, detection, control, etc. and the changes carried out by MEMS missile technology.

Using the convex model theory, the reliability-based analysis of frequency of the vibration control problem of structures with Interval parameters is discussed. Based on the theory of perturbation method, reliability analysis, and PNET method, the method of reliability-based analysis of eigenvalues of closed-loop vibration control systems with uncertain parameters is studied. And the distribution function of the random eigenvalues will not be computed other than their means and variances. The standard deviations of eigenvalues of the uncertain closed-loop systems can be used to estimate the reliability of frequency. The numerical results show that the present method is effective.

A topic discovery approach of the image has been proposed. First, the training images are segmented into some blocks. After clustering blocks, we obtained class set generated by cluster centers, and extracted all nouns from text annotation of each training image to obtain a keyword set. Secondly, the un-label testing image is also segmented into some blocks as same as training images, we calculated the correlation between the block and keyword, and the keyword set for each block may be obtained. Finally, the number of the same keyword appearing in the each block is calculated, we let the keywords with maximum to appear times be as the topics of the image. The experimental results confirm that proposed approach for the image is effectiveness and has good performance.

In order to enhance the signal intensity of VLC-LED receiver, this paper describes a receiver condenser which is designed based on optimized CPC (compound parabolic concentrator) by using a truncated method, for achieving the aim of boosting receiver’s ability of gathering light and enhancing signal intensity. The Monte Carlo-ray tracing simulation results shows that in the VLC-LED system, the optimized CPC condenser has those advantages, such as higher concentration ratio, larger concentrate light deviation angle.

The present situation of the UHVDC (ultra high voltage direct current) power transmission project is introduced, based on ±800kV UHVDC power transmission project put into commercial operation, the function design and application of GWS-1 remote equipment are carried out, the communication capability on IEC61850 is supported, the temperature problem of HP rx2660 is resolved, the GWS-1 remote equipment could meet the requirement of the UHVDC power transmission project is approved, and there is guiding significance on the research of RCI of UHVDC power transmission project.

Recently system security monitoring has meet several challenges. Therefore a system security monitoring approach based on complex event processing and dynamic structure-based neural networks is proposed in this paper. Firstly, complex event processing is used to handle real-time event streams and extract complex events from system security sensors. Secondly, the complex events from CEP would be used for further study by dynamic structure-based neural network. Finally the process of system security monitoring is showed and experiments would be applied to validate the feasibility, efficiency and precision of the approach.

This article will design the typical word operation question and use word 2010’s command button and after the button operation it will bring about the tracking of operation question training and automatic grading in label controls.

FBG concentration chenical sensor with three layer structure is proposed in this paper. And through experimental study and reasoning calculation to verify the three layer structure of the optical waveguide model, so the sensitivity characteristic of the Bragg wavelength to the refractive index of chemical solution is obtained. And the relationships between the concentration and the shift of Bragg wavelength of sucrose, ethanol, and Nacl solution are achieved. Finally the shifts of the Bragg wavelength with the external concentration are obtained by experiments.

Recently, many studies have suggested phosphate limitation (

To solve problems like slow computing speed and system operation speed, low system stability and reliability, which were encountered at implementing traditional region-county integration dispatching automation system (DAS) in a large scale region-county dispatching system, this paper provides a new type construction mode of region-county integration system, i.e. distributed and autonomous disaster tolerance backup system. It redesigns the structure of region-county integration system from aspects of network structure, model integration, data integration, application integration, separated operation and remote backup, provides wide area remote interconnection of region DAS with county DAS distributed at each county to make them become one logical set of system and realize share of data, technologies and equipment sources, save cost of system maintenance and construction, improve the reliability of DAS, realize remote disaster tolerance and backup and improve region-county operators' professional ability and technological level.

Traditional method mining for association rules between items in large and grand data sets is inefficient. In this paper we present an efficient method called BPMRA which is based on mapreduce and partition. We have compared BPMRA algorithm based multi-node and partition based single node method and performed some experiments. It turns out that BPMRA possesses high parallelism good stability and scalability, especially suitable for mining for association rules in large and grand data sets.

In order to separate effectively small deformation from GPS signal containing the error, Based on multiwavelet theory, the paper makes DGHM for GPS deformation monitoring signal processing, because the DGHM biorthogonal wavelet is with short support, orthogonality, symmetry ( antisymmetry ) and two approximation and other characteristics, in the same length of filtering, multi-wavelet method is more superior than traditional wavelet method, improves the signal to noise ratio, obtains higher accuracy, confirms correct and practical in the actual problem, the algorithm has opened a new way for deformation monitoring signal processing

NiTi shape memory alloy is considered to be the most important shape memory alloys for its salient superelasticity and shape memory effect,which are displayed in martensitic transformations.In this paper, first-principles plane-wave method is utilized to systemically investigate the geometrical and electronic structures of NiTi (100) surface.Calculated the adsorption of oxygen atoms on the Ti/ NITI different location .The formation energy, Millikan population analysis results show that the Oxygen atoms easy to be adsorbed on the surface of Ti end surface,formation of TiO2.

It is important to analyze mechanical relationship between lunar wheel and lunar soil for studying passing ability of regolith in lunar soil. Mechanical relationship between lunar wheel and regolith could be reflected by these parameters such as sinkage, drawbar pull, driving torque, motion resistance and slip when the lunar wheel moves. Thus, it is necessary to analyze these parameters of lunar wheel by soil bin test. The test results show that, the four parameters increase with slip and loading, except motion resistance of the test wheel which is under 70N at the speed of 25mm/s. The variations of the four parameters are not significantly influenced by velocity. The variations of the four parameters are significantly influenced by loading.

Three-dimensional digital model of hot rolling-mill housing was built. The natural frequency and vibration mode shape of the first 10 order modes of hot rolling mill housing were calculated using ANSYS software. The vibration mode shape was studied in detail. The striking vibration signal and subsequently the natural frequencies were measured by placing two 3-Dimensional accelerators in the key points of the rolling mill horsing. Theoretical calculations and experimental results verified each other，high agreement was shown between the experimental results and the theoretical results. The first 10 mode frequency all appeared in the experiment signal with low error. The main mode frequency (117.3Hz) of the experimental signal has the lowest error down to 0.07%.

This article has designed an low power granary temperature and humidity acquisition system, used the latest model MSP430F5438 belonging to TI company as the processor of the lower computer, colleceted temperature and humidity by SHT11, transmitted the collected physical data to the host computer through the SIM300 wireless transmission module and received data stored in the database. The host computer was done by using the C + + builder software, analysed the real-time physical datas and made reasonable warnings.

With wavelet technology used more widely in GPS deformation analysis, the paper will talk multi-wavelet (the second generation wavelet) theory used for GPS deformation monitoring data analysis. Due to multi-wavelet has a short branch set, orthogonal, symmetric (antisymmetric) and two order approximation characteristics, in the same filter length, using multiple wavelet on deformation monitoring signal can obtain better denoising effect than traditional wavelet. The paper studies signal adopting different preprocessing methods, makes a study of the selection problem in multi-wavelet preprocessing method. The GPS deformation monitoring signal is disposed using different multi-wavelet which adopts optima preprocessing method, and the paper makes a comparison to the conventional odd wavelet. The result confirms: multi-wavelet is more superiority than conventional wavelet, which decreases RMSE, advances SNR, obtains higher analytic precision, conforms the validity and practicability in physical problem, and offers a new road for deformation monitoring signal process

Based on the development practice of the pump performance test bed for the agricultural sprayer, a new program is proposed to cover the integrated mechanical structure of the pump performance test bed. Analysis was given to the various performance parameters of the pump test with regard to their testing methods, and specific methods of work performance test and inhalation performance test were also discussed to explore the test results. Finally, the issues that need to be focused were raised on the design and manufacture of pump performance test for the sprayer.

In order to solve the problem about the tension detection of the multi-hoisting wire rope, this paper designs dynamic tension detection system of the multi-hoisting wire rope. The system can real-time detect the tension of rope, alarm to overload, imbalance and other security hazards during the operation, and guarantee the safe operation of the elevator. This paper designs a tension sensor for the hoist wire rope. The sensor uses the strain gauge as the measurement principle and the spoke as the flexible structure. It has the advantages of large measuring range, small size, anti-interference etc. At the same time, this paper adopts configuration software as detection system software. The software system includes the show of the rope tension and its force diagram, the simulation of hoisting state, and the alarm function to security hazards etc. It realizes online detection of the tension.

The blend composite materials of bio-ethanol byproduct-Poly(lactic acid) (PLA) were produced by a twin-screw extrusion process. Effects of bio-ethanol byproduct (BEB) contents and different compatibilizers on properties of composite materials were investigated. The research showed that with the increase of contents of bio-ethanol byproduct, the mechanical properties decreased. The mechanical properties of composites were improved by adding the compatibilizers, especially the polypropylene grafted maleic anhydride (PP-MAH). When the PP-MAH content was 2.5%, the mechanical properties of the composite materials were superior to others.

Aiming at the complicated situation of artificial testing function materials, a set of automatic test system based on Agilent E4980A is developed. In the control software edited by Visual Basic 6.0, the test conditions (temperature, frequency, voltage, etc.) are pre-set, and the system automatically controls the temperature of the temperature control box through PID algorithm, achieving the real-time test voltage and frequency of Agilent E4980A. The card shows the readings on the test results of a plurality of functional materials at various stages of temperature conditions , automatically completing the storage and analysis of electrical parameters. The system is able to achieve the automatic control of the temperature control box and Agilent E4980A, presenting the comparative benefits including the function of this system being more comprehensive, more convenience in operation, and higher degree of automation advantages . It can be a good method and reference resource available for the development of such test system.

The preparation and application of polyurethane immobilized nitrifying bacteria pellets for surface water treatment was studied. The removal of ammonia nitrogen from micro-polluted source water by polyurethane immobilized nitrobacteria pellets with a stuffing ratio of 10% in volume in an up-flow inner circulation reactor was investigated with the system operated continuously under the following conditions: temperature 20°C--30°C, DO 3--5 mg/L, and pH 7.1--7.3. The continuous removal rates of NH4+-N remain above 90% and4+-N concentration in the produced water was less than 0.5 mg/L with the hydraulic reaction time (HRT) controlled at 0.5 h. The results verified that polyurethane immobilized nitrobacteria pellets have a great potential for micro-polluted source water treatment applications.

Based on the analysis of several main evaluation index systems of regional science and technology (S&T) progress in-country and overseas, and refer to the idea of system dynamics and balanced scorecard, this paper explored the causality and dynamical structure of subjective and factor in index systems of regional S&T progress, probed its rules and relationship. After examined and reconstruction the statistical monitoring index system of S&T progress designed by Ministry of S&T in China, this paper putted forward a new framework of evaluation index system of regional S&T progress.

As for shortcomings of PID and modern control method in crane anti-swing system, we introduce the fuzzy theory to the crane anti-swing on base of analyzing the crane trolley’s moving dynamic model. The cooperation between the position fuzzy controller and swing fuzzy controller achieve the goal. We use the fuzzy control system of self-adjustable quantization factors and scale factors to solve the problem that have the oscillation in limit areas causing the load lasting swing during the trolley moving position control. According to the simulation, it can solve the problem and eliminate the steady-state error completely and improve enhance the adaptivity of system. It can make the trolley reach the designation in 15s and keep the load steady.

This paper attempts to find out a performance evaluation method that is suitable to the entire workflow characteristics through the analysis of the Current Situation about Performance Assessment of grass-roots local tax departments with the theory of performance evaluation, which provides some suggestion for local tax authority to improve management and service level.

The evaluation of clustering validity is important for clustering analysis, and is one of the hottest spots of cluster analysis. The quality of the evaluation of clustering is that optimal number of clusters is reasonable. For fuzzy clustering, the paper surveys the widely known fuzzy clustering validity evaluation based on the methods of fuzzy partition, geometry structure and statistics.

The problem of fatigue is becoming one of the factors impacting on the working and studying people. Therefore, how to detect whether the people are tired simply and effectively is paid attention to by more and more researchers. A novel method of fatigue testing based on fuzzy logic and image processing is proposed in this paper. Firstly, positive map and side elevation are extracted through camera device. Then motion detection determined to locate human faces and the frequency of eyes opening and closing is derived by using image processing techniques. Finally the angle between the head and the shoulder is calculated combined with a representation of time function and a fatigue threshold is set up. All of these are determined to estimate the degree of fatigue. Experimental results show that, the method can quickly detect the degree of fatigue simply.

For the shipborne satellite antenna system，owing to the continuous change of the carrier’s position and pose as the time passing, we must conduct real-time measurement on the pose of satellite antenna, so that the satellite can be aimed through servo control system. In this paper, the hardware and software about the shipborne satellite antenna system are introduced. Three-dimensional closed-loop servo control system which is made of three kinds of pose sensors is implemented to isolate the links between the antenna pose and the carrier’s position and pose. FSK serial communication is adopted to realize a reliable control commands and data transmission between the control unit above the deck and the control unit under the deck. Conical spiral scan based on the best AGC signal realizes automatic tracking satellite and locking it. The result of the examination shows that the pointing of antenna is of steadiness, precision(the point precision is less than 0.3 degrees), real time and speediness(the capture time is less than 25 seconds ).

In order to satisfy increasing demand for personalized products, through analysis characteristic parameters of individual factors such as the various parts of the body size, body weight, body surface area, factors affecting the performance of the machine and their mathematical relationships, three levels of customization model based on human engineering by using mechanics and control theory was established to help designers to design personalized products, best meet customer's all aspects of demand. Finally, three levels of customization model was applied to Man-machine system (human-bicycle system for the design case) to show application of the model.

Regional technological innovation ability is increasingly becoming the determining factor to attain an international competitive advantage for the areas, as well as to achieve regional economic growth and development. But in the same time of raising the regional technological innovation ability, it is also necessary to continuously improve the efficiency of regional technological innovation, so as to increase the resources efficiency. We evaluate the efficiency of regional technology innovation for China's 30 provinces and municipalities using comprehensive evaluation model combined principal component analysis and DEA. According to evaluation results, we think that the overall efficiency for regional technological innovation is at the low level, and most areas is at the stage of increasing returns to scale, that account for a common problem of insufficient investment in the process of regional technological innovation.