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For the interference fit joint of massive flywheel assembly, Studies the reasonable amount of interference and its heating temperature options. Analysis the advantages and disadvantages of various assembly way, reasonable assembly method is proposed, Designed the corresponding assembly tooling , Use the cone positioning and the method of hydraulic push to ensure the higher precision alignment, Provides a reasonable reference for interference fit joint method for the flywheel .

Traveling wave in transit, wave head is easy to produce distortion and affected by environmental interference, so accurately measuring the head of traveling wave singularity occurrence time become extremely difficult. The key to improve the precision of traveling wave detection is to accurately capture the happening time of wave head of singular points. Recently, traveling wave singularity detection usually use wavelet, EMD-HHT transform technique, but both have mixing phenomenon, affecting the accuracy of detection. In this paper, we propose a new method that use Duffing chaotic oscillator to suppress traveling wave interference signal. By Matlab simulation and it is proved that this method can effectively suppress noise singular point. Meanwhile, we propose an anti-mixing EEMD-HHT wave head detection technology. Through simulation experiment and field test, it is proved that, compared with EMD, EEMD can more accurately identify the traveling wave arrival time, detection accuracy increasing by 1.52%.

By considering the momentum source term of surface tension and the source term of heat transfer in gas-liquid two phase flow, a computational model based on the VOF was established to discuss the rules of the temperature outside tube in the evaporative air cooler.The result shows that under a wind velocity and spray density, the temperature of water near the wall dropped sharply at first, with wall distance increasing, finally to environmental temperature, and with annular angle increase, the temperature of water film increases. And the higher the wind speed, the higher the water film temperature, but the changes of wind speed has little influence on the temperature within less than 60 º angle. The smaller the spray density, the higher water film temperature.

Improving the machining precision mechanical manufacturing field is an indispensable chapter topic. In this analysis focuses on the rail straightness, process system stiffness, milling way, cutting layer parameters, tool wear, thermal deformation of the workpiece spindle axis traverse peace pliers jaws of irregularities in the machining precision flatness influence. Milling cutting process parameters of different layers, different milling heat, different deformation of the workpiece, resulting flatness error is different. Different milling methods and different milling force also affect flatness errors. Therefore, the workpiece machining pass these factors need to be considered. And proposed a solution for uneven of flat-nose pliers jaws and surface of workpiece.

When an electromagnetic field propagates through a linear but dispersive medium, the front edge (the launching fringe of the waveform where the field is first turned on) propagates precisely at the speed of light in vacuum by first timing on t1=tfront=（z/c）and the main signal (the main part of the field) follows up with group velocity which is characterized by the frequency-dependent refractive index of medium by second timing on t2=tgroup=(z/vgroup)=[n(φ)z/c] .The distinct wave-packets progress from tfrontto tgroup(i.e. from the front-edge-timing to the main-signal-starting timing) are well known as optical precursors. It was believed that precursors are an ultra-fast phenomena, persisting only for a few optical cycles, and that they have an exceedingly small amplitude and two different kinds of spike-type wave-packet (i.e. Sommerfeld precursor and Brillouin forerunner). Both exact wave shape for electromagnetic wave while it goes into a linear time-invariant, lossless plasma system is reported.

The traditional method for detecting speech signal needs the help of microphone, which must be placed closely to the body of human beings. To some extent, this method would bring several inconveniences. Non-contact speech detection method breaks through the limitation of the traditional method, this new kind of speech obtaining method can detect speech signal quite well even in strong noisy background. However, this non-contact speech detecting system also produces some electromagnetic noise and circuit noise, which reduced the quality of radar speech signal. Therefore, based on the good time-frequency analyze performance, the lifting scheme was also proposed in this paper to remove noise from radar speech. Comparing to classical enhancement algorithm, such as spectral subtraction and Wiener filter, the proposed algorithm can remove the component of noise availably and reserve the original pure speech signal in a promising way.

This research aimed to separate the signals of respiration and heartbeat effectively from the biological radar echo signals of vital signs detecting platform. Therefore the characteristics parameters of the respiration and heartbeat could be extracted to provide the basis for clinical diagnosis and disease prevention. This paper put forward a separation algorithm of heartbeat and respiration based on LMS adaptive harmonic cancellation, the combined harmonics of the breathing signal was regarded as a reference input signal of the adaptive filter to improve the algorithm. Related experiments were designed to conduct filter processing. Results show that the algorithm proposed proved to be more effective in the signals separation of respiration and heartbeat.

Terminal Sensitivity Projectile is served as the research object and the hardware-in loop simulation technology is employed to design the indoor hardware-in loop simulation system for infrared sensor of terminal sensitivity projectile. This system employs the Multi-Gen Creator to build the scene model and the target three-dimensional geometrical model as well as employs the Vega to produce the digital scene of detection field for infrared sensor. Meanwhile, the detection system of terminal sensitivity projectile--- infrared sensor is served as the substance and introduced into the simulation system to participate in the test and consist of the closed loop with other physical models and mathematical models as well as complete the real-time simulation function of terminal sensitivity projectile. The simulation result indicates that the infrared sensor can completely identify the target and is provided with such advantages as low false detection ratio and low omission ratio.

Surface wave dispersion imaging approach is crucial for multi-channel analysis of surface wave (MASW). Because the resolution of inversed S-wave velocity and thickness of a layer are directly subjected to the resolution of imaged dispersion curve. The τ-p transform approach is an efficient and commonly used approach for Rayleigh wave dispersion curve imaging. However, the conventional τ-p transform approach was severely affected by waves amplitude. So, the energy peaks of f-v spectrum were mainly gathered in a narrow frequency range. In order to remedy this shortage, an improved τ-p transform approach was proposed by this paper. Comparison has been made between phase shift and improved τ-p transform approaches using both synthetic and in situ tested data. Result shows that the dispersion image transformed from proposed approach is superior to that either from conventionally τ-p transform or from phase shift approaches.

Due to the limited scientific level in forecasting seism, it is still not available to provide an accurate imminent prediction. As seism brings large amount of building destruction and casualties, taking effective anti-seismic measures to fortify and remodify buildings becomes the worldwide critical work in seism proofing and hazard reduction.

The MASW method is robust in determine shear wave velocity of shallow site because the dispersive properties of Rayleigh wave was dominated by shear wave velocity of subsurface. Using this method, an assumption that the earth model is one dimensional and horizontal layered must be put to simplify the real earth model without considering the lateral variation. However, it is not always the truth. In order to obtain a two dimensional S-wave velocity profile of shallow site, a CMP cross-correlation (CMPCC) method was proposed by Hayashi and Suzuki (2004) to approximate two dimensional S-wave velocity profile with one dimensional inversion procedure. In order to verify its approximate resolution, a horizontal stepped layer model and a dipping layer model were chosen. The synthetic wave fields of the two models were calculated by staggered grid finite difference method. Result shows that this method can only be used to approximate horizontally stepped layer model and cannot be used to approximate dipping layer model.

Single-drop microextraction (SDME) coupled to capillary gas chromatography (GC) was established for the determination of four phthalate esters in wastewater, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-octyl phthalate (DnOP) and butyl benzyl phthalate (BBP). The SDME parameters such as extractants, extracting time，stirring rate and immerging depth of needle point were studyed and optimized. The abovementioned phthalate esters were quantified by external standardization method using GC coupled with a flame ionization detector (FID). The linear regression calibration curves, detection limits (S/N=3) and the linear ranges of the method for determining each phthalate were determined, respectively. The concentrations of components abovementioned in a real wastewater sample, the average of the recoveries obtained in the spiked wastewater samples and the corresponding relative standard deviations were determined, respectively. The results showed the proposed method several attributes, friendly enviroment, economic and highly efficient pretreatment, less time, simplicity, sensitivity, accuracy and wide linear range and so on.

Single-drop microextraction (SDME) coupled to capillary gas chromatography (GC) was established for the determination of seven volatile halogenated hydrocarbons in wastewater, including chloroform (CF), carbon tetrachloride (CT), trichloroethylene (TCE), bromodichloromethane (BDCM), perchlorethylene (PCE), dibromochloromethane (DBCM) and bromoform (BF). The SDME parameters such as extractants, extracting time，stirring rate and immerging depth of needle point were studyed and optimized. The abovementioned halogenated hydrocarbons were quantified by external standardization method using GC coupled with a flame ionization detector (FID). The linear regression calibration curves, detection limits (S/N=3) and the linear ranges of the method for determining each halogenated hydrocarbons were determined, respectively. The concentrations of componds abovementioned in a real wastewater sample, the average of the recoveries obtained in the spiked wastewater samples and the corresponding relative standard deviations were determined, respectively. The results showed the proposed method several attributes, friendly enviroment, economic and highly efficient pretreatment, less time, simplicity, sensitivity, accuracy and wide linear range and so on.

By combining the Data Envelopment Analysis (DEA) method, from the view of time and district, this paper carries out a dynamic evaluation of resource allocation efficiency of China’s telecommunication industry from 1973 to 2008. The results show that technical efficiency indicator and technological progress indicator are the major factors of resources allocation of China’s telecommunication industry. It analyzed and studied all previous reorganization and regulation effects to the telecom with the reference to the efficiency changes of the telecom industry. Based on the non-Archimedean infinite model C2R of the Data Envelopment Analysis, combined with characteristics of inputs and outputs of China’s telecommunication industry, the paper sets up an indicator system of inputs and outputs as well as an overall efficiency evaluation model China’s telecommunication industry.

The overlapping chromatograms and spectra of sulfonamides, sulfadiazine (SD) and sulfamethoxazole (SM) in both synthetic samples and pharmaceutical tablets in the presence of uncalibrated and interfering sulfanilamide (SN) were resolved by HPLC-DAD combined with SWATLD algorithm. The elution time was set from1.077 min to 1.624 min and the detection wavelength was chosen from 230 nm to 316 nm. The recoveries of SD and SM were (98.1 ± 4.8)% and (100.1 ± 1.6)%, respectively. The satisfying results show this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

Speech is an important method for human communication. In this paper, we developed a new method for detecting speech signal. Because of the advantage of this speech detecting method, it has great potential application value in many fields. Simultaneously, basing on the good capability of wavelet packet for analyzing time-frequency signal, this paper also developed an algorithm of wavelet packet threshold by using hard threshold and soft threshold for removing noise. Comparing to spectral subtraction and Wiener filter speech enhancement algorithm, the proposed algorithm takes on a better performance on noise removing and speech signal reserving.

The highly overlapping chromatograms and spectra of the major metabolites of asprin, salicylic acid (SA) and gentisic acid (GA) in the presence of uncalibrated and interfering pyrocatechuic acid (PA) were resolved using HPLC-DAD combined with SWATLD algorithm. The elution time was set from 0.6628 min to 0.9495 min and the detection wavelength was chosen from 268 nm to 332 nm. Both SA and GA were determined simultaneously in aqueous solution with their recoveries were (100.5 ± 6.7) % and (109.2 ± 5.3) %, respectively. The satisfying results indicate this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

Heart rates and breathing rates are widely used to assess the health state of human in clinic. Tranditional method uses eletrodes or sensors touching the body to measure electrocardiography (ECG) and respiratory signals.A vital signs monitor via a micorwave sensor was disscused to contact-free measurement of the heart rate and breathing rate. Comparison of vital signs derived from the microwave sensor and tranditional contact monitor demonstrated that there were no significant differences between each other, which suggested the contact-free vital signs monitor may prove a practical alternative method to measure heart rate and breathing rate.

To optimize the storge and retrieval process for Plasma Display Panel (hereafter abbreviated as PDP) panel aging, one dynamic cargo location allocation method is proposed, and one access time model is also established to achieve the shortest location allocation for the PDP panel aging steroscopic warehouse based on expert system. The constraints of the optimization model include redundancy requirements of steroscopic warehouse, PDP panel aging stacker running speed, time requirements, in-out warehouse strategy requirements and so on. Tests show that the dynamic location allocation system of the PDP panel aging steroscopic warehouse based on expert system is of high stability and can save energy consumption and time consumption in the access process, thus meets the actual requirements of production.

In order to satisfy the running requirements of Automated Storage and Retrieval System’s control system with big load, high speed and high accuracy, the design is proposed by adopting PLC and servo motor control. The Ethernet , MELSECNET/H ,CC-LINK and serial communication of Mitsubishi is adopted to satisfy complicated worksite environment, meanwhile the semi-closed loop control and full-closed control is adopted to satisfy the demand of high speed high accuracy smooth running servo control system. The practical application verifies that the system is of high reliability and stability, thus greatly meets the production requirements, and saves considerable labor force.

With the continuous research in earthquake engineering, great advances have been made in the theoretical research of ground motion attenuation. A lot of new achievements and views [1,2,3] provide the theoretical basis for the improvement of the ground motion attenuation experience models and the parameter estimation. Additionally, it provides a good environment for deeper study on the ground motion attenuation by the increase of strong motion records and the improvement of pertinent information. In this paper, the improved two-step method is put forward, and the regressed ground motion attenuation coefficients are obtained by the improved models and analysis method. This method not only considers the correlation of magnitude and distance, but also makes the regression coefficients more stable. The results can better show the characteristics of the ground motion attenuation.

Purpose: A multi-leaf collimator leaf sequencing comparison program in the sense that it translates beam intensity maps into the least number of MLC field segments was presented. Methods: The IMRT leaf sequencing calculation program based on Galvin, Bortfeld algorithms was constructed. The output of the leaf sequencing program were the number of segment and the total number of monitor unit. Results: Assuming 15 x 15 bixel fields with an average of 10 intensity levels, Bortfeld algorithm could yield better result on example 1 while Galvin algorithm yielded better results on example 2. Conclusions: This represented a useful tool for optimizing the leaf sequencing of static multi-leaf collimator that can yield shorter treatment time and higher utilization of photons by comparing with the total number of monitor units and number of segments of existed typical algorithms. It was an effective strategy and could be applied in commercial Treatment Planning Systems.

Local image representation based natural image classification is an important task. SIFT descriptors and bag-of-visterm (BOV)method have achieved very good results. Many studies focused on improving the representation of the image, and then use the support vector machine to classify and identify the image category. However, due to support vector machine its own characteristics, it shows inflexible and slower convergence rate for large samples，with the selection of parameters influencing the results for the algorithm very much. Therefore, this paper will use the improved support vector machine algorithm be based on ant colony algorithm in classification step. The method adopt dense SIFT descriptors to describe image features and then use two levels BOV method to obtain the image representation. In recognition step, we use the support vector machine as a classifier but ant colony optimization method is used to selects kernel function parameter and soft margin constant C penalty parameter. Experiment results show that this solution determined the parameter automatically without trial and error and improved performance on natural image classification tasks.