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In view of problem that current switched reluctance drive systems are lack of friendly human machine interface to display running state of the system and set given parameters, the paper proposed a design scheme of human machine interface of switched reluctance drive system based on simplified ModBus communication protocol. It gave general structure of the switched reluctance drive system, and introduced design of serial communication circuit and communication program in the human machine interface. Debugging result shows that the human machine interface runs stably and realizes functions of friendly display and online parameters modification for the switched reluctance drive system.

For the equivalent nonlinear dynamic system of brushless DC motor, the center manifold theory and Hopf bifurcation theory are used to discuss the Hopf bifurcation behaviors of original system, the Hopf bifurcation control problem of original system is investigated using a state feedback controller, and the effects of control parameters on the position of bifurcation point, bifurcation type and amplitude of periodic solution are analyzed. The research results show that the positions of Hopf bifurcation points can be changed and even the Hopf bifurcation points are eliminated by the linear control, and the bifurcation type and the bifurcation amplitude of periodic solution can be changed by the nonlinear control. Finally, the numerical simulations show the effectiveness of the proposed controllers. [ABSTRACT FROM AUTHOR]

To obtain damage behaviors in hard borosilicate glass, proton-induced ionizing and nonionizing energy loss were calculated by using the SRIM Monte Carlo program. The result shows that for protons with the energy range of 40 -200 keV, the main damage is limited to the surface of borosilicate glass, and the ionizing energy loss, with the peak position of 80keV, is the main type of energy loss. The nonionizing energy loss increases with the decreasing of energy and induces the vacancy production of O, Si and B etc. Both vacancy distribution and phonon distribution, similar to the proton deposition, follow the property of Bragg-type curve. Both the ionizing energy loss and nonionizing energy loss by protons with the energy range of 40 -200 keV can change the microstructure of hard borosilicate glass. [ABSTRACT FROM AUTHOR]

According to the characteristics of bidirectional and reversible effect of multiple piezoelectric effects in single piezoelectrics, theoretical analysis is carried on for multiple piezoelectric effects realizing displacement self-sensing of piezoelectric actuators. Thus, one to one correspondence between multiple converse and multiple direct piezoelectric effects is illustrated, and the feasibility of separating electric displacement caused by multiple direct piezoelectric effects from dielectric electric displacement is analyzed. Through a referenced capacitor combined with current integration and differential proportional operational circuit,a decoupling method which is easier for practical engineering application than electric bridge circuit is obtained. The experiments justified the method through a PZT-5 stack actuator. Meanwhile,linear coefficient of the secondary direct piezoelectric effect is obtained for PZT-5 stack. And the influence of tertiary piezoelectric effect on resolution and precision of piezoelectric self-sensing actuators is further analyzed. The study results can provide a new approach for the performance improvement of self-sensing actuators. [ABSTRACT FROM AUTHOR]

The failure of normal excitation or freewheeling often occurs when power converter is damaged. The fault type was then analyzed in an asymmetric half-bridge converter, applied to a 12/8 switched reluctance drive (SRD). The analytical solution of the phase winding current was obtained by formula derivation under normal and fault conditions. Detailed discussions were presented about the amplitude changes of the DC bus current and its digital analysis results under different work conditions. The short-circuit and open-circuit fault detect method of transistors was also proposed, which was connected to the voltage pulse width modulation ( PWM) signals and the DC bus current. A model was used to build the pattern of the power converter of SRD system and the simulation has been implemented with mat-lab. The short-circuit and open-circuit fault simulation result of transistors are agreement with the theoretical analysis results. The detect method can identify the fault phase and determine the fault type. As a result,it has been proved that the method is effective. [ABSTRACT FROM AUTHOR]

Objective: To study the structure and function of human sperm mitochondria before and after the freezing-thawing process., Methods: Human sperm from healthy donors were subjected to the slow freezing-thawing process, and the sperm mitochondrion-related indexes compared before and after cryopreservation. The ultrastructural changes of the mitochondria were observed under the projection electron microscope, the mitochondrial membrane potential (MMP) and seminal adenosine triphosphate (ATP) content measured by immunofluorescence labeling and ELISA, respectively, and the sperm oxidative stress related indexes detected before and after sperm cryopreservation., Results: Electron microscopy showed loose structures and widened crests of the sperm mitochondria, some with vacuole-like changes after the freezing-thawing process. The sperm after cryopreservation, compared with those before it, exhibited significantly increased contents of oxygen free radicals (［11.6 ± 3.8］% vs ［9.6 ± 4.1］%, P < 0.05) and malondialdehyde (［3.2 ± 1.4］ vs ［2.3 ± 1.2］ nmol/108, P < 0.05), but decreased antioxidant capacity (［0.6 ± 0.4］ vs ［0.9 ± 0.4］ nmol/108, P < 0.05), superoxide dismutase activity (［0.9 ± 0.4］ vs ［9.1 ± 3.9］ nmol/108, P < 0.05), MMP (［52.2 ± 6.2］% vs ［55.7 ± 4.9］%, P = 0.026) and ATP production (［56.5 ± 9.0］ vs ［61.3 ± 10.4］ pmol/106, P = 0.014)., Conclusions: The freezing-thawing process can cause ultrastructural disorder of human sperm mitochondria, reduce their membrane potential and decrease their ATP production.

In the smoothing pretreatment for the quantitative analysis of hydrocarbon mixed gases by Fourier transform infrared analysis (FTIR), the Savitzky- Golay filter is usually used as one of the smoothing preprocessing methods in the Fourier transform infrared spectrum data smoothing pretreatment. However, the parameters of the Savitzky-Golay filter such as the polynomial order and frame size are not easy to decide. There is no one unified choice basis. Users usually adopt multiple sets in the special data set to try, and then select a set of relatively optimal data as the optimizing parameters of the Savitzky-Golay filter. The optimal selection method of the Savitzky-Golay filter parameters was explored, and the concrete calculation equations were deduced according to the relation among the normalized cut-off frequency, the normalized beginning frequency of the stopband, the normalized first side lobe peak frequency of the stopband, the normalized first side lobe peak amplitude with the polynomial order and frame size of the Savitzky-Golay filter parameters. Then when the polynomial order and frame size are set as 8 and 11 respectively according the above conclusion and the characteristics of the actual spectral data, the Savitzky - Golay filter smoothing effect is optimum. Through the acquisition the concentration of 0.1%, 0.2%, 0.5%, 1%, 2%, 5% for the actual CH4 spectra, the relative maximum and minimum error of the raw spectra converted absorbance were 17.230 5% and 0.243 0% respectively, and the relative maximum and minimum error of the smooth spectra converted absorbance were 0.088 0% and 0.088 0% respectively in the second absorption peak. The relative error of converted absorbance was basically stable through the Savitzky-Golay filter after the spectral data preprocessing and it was relatively low, so, it laid a foundation for the late spectral data accurate qualitative and quantitative analysis.

The generalized two-dimensional correlation spectroscopy and Fourier transform infrared were used to identify hydrocarbon isomers in the mixed gases for absorption spectra resolution enhancement. The Fourier transform infrared spectrum of n-butane and iso-butane and the two-dimensional correlation infrared spectrum of concentration perturbation were used for analysis as an example. The all band and the main absorption peak wavelengths of Fourier transform infrared spectrum for single component gas showed that the spectra are similar, and if they were mixed together, absorption peaks overlap and peak is difficult to identify. The synchronous and asynchronous spectrum of two-dimensional correlation spectrum can clearly identify the iso-butane and normal butane and their respective characteristic absorption peak intensity. Iso-butane has strong absorption characteristics spectrum lines at 2,893, 2,954 and 2,893 cm(-1), and n-butane at 2,895 and 2,965 cm(-1). The analysis result in this paper preliminary verified that the two-dimensional infrared correlation spectroscopy can be used for resolution enhancement in Fourier transform infrared spectrum quantitative analysis.

In the multicomponent mixture hydrocarbon gases Fourier transform infrared (FTIR) quantitative analysis, especially for light alkane gases, it is not easy to establish the quantitative analysis model because their IR spectra absorption peaks are seriously overlapped. Aiming at this problem, the Tikhonov regularization algorithm was used to select the characteristic wavelengths for seven kinds of light alkane mixture gases FTIR which are composed with methane, ethane, propane, iso-butane, n-butane, iso-pentane and n-pentane. And then the wavelength selection was used to establish the quantitative analysis model. By comparing the analysis characteristics wavelength selection and TR parameters optimization of the mixed gases in the infrared all wave band, the first absorption peak band and the second peak band, the characteristic wavelength of 7 kinds of gases were selected by Tikhonov algorithm. The wavelength selection and Tikhonov regularization parameters were used to test the actual measured methane spectral data, and then we got that with other gas components the max cross sensitivity was 11.153 7%, the minimum cross sensitivity was 1.239 7%, and the root mean square prediction error was 0.004 8. The Tikhonov regularization algorithm effectively enhanced the accuracy in the light alkane mixed gas quantitative analysis. The feasibility of alkane gases mixture Fourier transform infrared spectrum wavelength selection was preliminarily verified by using the Tikhonov regularization algorithm.

For the defects of requiring carrier gas and regular calibration, and low safety using chromatography to on line monitor transformer dissolved gases, it was attempted to establish a dissolved gas analysis system based on Fourier transform infrared spectroscopy. Taking into account the small amount of characteristic gases, many components, detection limit and safety requirements and the difficulty of degasser to put an end to the presence of interference gas, the quantitative analysis model was established based on sparse partial least squares, piecewise section correction and feature variable extraction algorithm using improvement TR regularization. With the characteristic gas of CH4, C2H6, C2H6, and CO2, the results show that using FTIR meets DGA requirements with the spectrum wave number resolution of 1 cm(-1) and optical path of 10 cm.

A method for online quantitative analysis system of alkane gaseous mixture with near infrared spectroscopy is described in the present paper. A single plane diffraction grating is used as the principal device in the monochromatic spectrum system. The key parameters of the monochromator were deduced and calculated in detail. A quantitative analysis system was designed and constructed according to the parameters. The narrow-band beam testing experiments and spectral scanning experiments of seven kinds of single-component alkane gases were accomplished on the above hardware system platform. The narrow-beam experiments show that a 10 nm narrow-band beam spectra was successfully obtained by the monochromatic system when the entrance slit width is 2 mm. And a step-scanning resolution of the outgoing beam's center wavelength with 0.1 nm can be realized within the spectra of 1.2-1.8 microm. The spectral scanning experiments indicate that there was some stronger characteristi absorption spectrum existing between the spectra of 1.6-1.8 microm, which is consistent with the HITRAN spectral database. And there is serious cross-aliasing phenomenon existing among the absorption spectra. These experiments demonstrate that this method has a successful application in mixed gas monitoring and on-line analysis with the characteristics of simple structure and low cost. And it also provides further technical reserves and opens a path way to spectral analysis in the follow-up studies.

Objective: Canine model established for tracheal defect reconstruction, to investigate the outcome of tracheal reconstruction with combination of polypropylene and flap., Methods: About 3.5 to 4 centimeter cervical trachea was resected and replaced with artificial trachea made from monofilament knitted polypropylene and surgical flap. Covered stent was implanted postoperatively. Survival period and quality of life were recorded, bronchofibroscopy, X-ray films and HE sections were performed., Results: Six dogs survived well and another two died. The causes of death were respiratory failure in 1 and infection in another. Stenosis of anastomosis in 1 was recorded during survival period. The dogs started drinking and eating on the second postoperative day, no dyspnea was found. The animals were sacrificed at 2, 4, 8 weeks and 6 months after surgery. Soft tissue growth was found in polypropylene net 2 weeks after surgery and more at 4 weeks. The polypropylene net was covered completely with soft tissue at 8 weeks and 6 months postoperatively, the hardness and sustentation degree were enhanced following the growth and fibrosis of soft tissue. The squamous epithelium and columnar epithelium were observed healing well by HE staining method., Conclusions: One-stage operative artificial trachea made from monofilament knitted polypropylene which has good histocompatibility and surgical flap is the closer artificial trachea to native trachea. It has a promising prospect in clinical use.

Objective: To evaluate the feasibility and effect of mesenchymal stem cells (MSCs)-poly (lactic-co-glycolic acid) (PLGA) scaffold as transplant in repair of skin damage., Methods: MSCs were isolated from the bone marrow of femur of a one-month-old New Zealand rabbit, cultured, and labeled with diamidino-phenyl-indole (DAPI). Porous foam scaffolds were made with PLGA. MSCs of 2 - 3 passages were seeded on the scaffolds. Fluorescence microscopy and scanning electron microscopy were used to observe the growth of the MSCs. Six pieces of skin 2 cm x 2 cm in size were cut from the backs of five 5-month-old new Zealand rabbits and then 4 pieces of MSCs- PLGA scaffolds and 2 pieces of porous foam PLGA scaffolds of the size similar to these of the cut skin were transplanted to the skin wounds. The wound healing was observed. Five days after the operation, samples of newly-grown skin were taken to undergo HE staining, VG staining, and microscopy. Immunofluorescence histochemistry was used to detect the cytokeratin AE1/AE3., Results: Scanning electron microscopy showed that holes were distributed evenly on the surface of and inside the porous foam PLGA scaffolds Fluorescence microscopy and scanning electron microscopy showed that the MSCs grew well on the porous foam PLGA scaffolds and the number of MSCs increased gradually. Animal experiment showed that with the degradation of the polymer scaffolds the wounds were gradually covered by newly grown skin similar to the normal skin. Immunofluorescence histochemistry showed fluorescence positive cells in the stratum corneum and follicles. The wounds transplanted only with porous foam PLGA scaffolds formed new skin too, however, in the dermis of the new skin only thickened fibrous scars and a few follicles were seen., Conclusion: The compound of MSCs-PLGA polymer is effective in wound healing.

Entropy-based divergence measures have provided an impelling tool in evaluating sequence complexity, predicting CpG island, and detecting borders between coding and non-coding DNA regions etc. In this paper, two new divergence measures: the alpha-KL divergence and the alpha-Jensen-Shannon divergence were defined and a coarse-graining vector of amino acids- corresponding codons was proposed according to codons GC-content, in order to improve the computational approach to finding borders between coding and non-coding in rice. A comparison of the accuracies gained by different vectors (the Jensen-Shannon divergence, the Jensen-Renyi divergence, the alpha-KL divergence and the alpha-Jensen -Shannon divergence) showed that recognition efficiency based on the new information measures with the vector coarse-graining increase by 4-5 times than that of Bernaola's method in the 'stop codon' of coding regions in rice.

Fructus Xanthii is commonly used in rhinology, especially used in treatment of chronic rhinitis and sinusitis. But Fructus Xanthii is toxicant, and it maybe result in poisoning when used excessively, without preparation or in inappropriate preparation. This article reviewed all poisoning cases from 1960 to 2000, its toxicology and methods for detoxification