Advanced Materials Research Vols. 955-959

Abstract: This document mainly explains a new method of evaluate the energy harvested from vortex-induced vibration phenomenon of the circular cylinder. The external flow field of the cylinder has been solved by a RANS method together with the one equation turbulent Spalart-Allmaras model. The feedback effect of the circuit has been calculated by a matrix method to obtain the damping and the natural frequency of the system. Then the voltage output has been solved by a quasi-steady method. Finally, we discuss the computing method of the power output.

Abstract: Magnetostriction of transformer core plays a dominated role in the vibration of transformer equipment. In order to simulation the magnetostrictive effect, a equivalent magnetostrictive force model is introduced in this paper. Elongation-based models are used to deduce the magnetostrive force. Elongation-based models employ experimental data from magnestrictive elongation to bulid the relation between magnestrictive strain and magnetic flux density, and can be used for harmonic analysis. Magnetostrictive force on single slicion sheet is deduced by strain energy density and energy conservation principle. The force is applied on the single silicon sheet model to analysis the deformation caused by magnetostriction.

Abstract: The finite element model of a 1000MW unit was set up and vibrations of the three-bearing structure were studied. The results show that the generator supporting characteristics have great effects on vibrations of the three-bearing structure. Many factors are needed to be considered when field balancing. The generator supporting characteristics should be considered when judging the type and axial position of imbalances. Repeated balancing are invalid and even the vibrations diverge if just following simply the harmonic component method to determine directly the imbalance types. The conclusion reliabilities were further verified with the tests.

Abstract: A commercial vehicle was taken as the study object to establish vehicle rigid-body dynamics model which included seventeen-degree-of-freedom. This model consisted of three rigid bodies which were power-train, frame and body and there were flex connections among the rigid bodies. The model was used to carry out simulating calculation and analysis of vehicle ride comfort. By comparing simulation results with test results, some improvement measures for vehicle ride comfort at idle speed were presented in this paper.

Abstract: A marine steam turbine control valve is taken as the research object in this paper, the vibration response is studied under pressure pulse excitation. The transient flow field analysis is made using the method of large eddy simulation to obtain the time-domain information of the pressure pulsation. Then, the analysis of vibration based on coupled modes, research vibration response and resonance problems of the control valve. The study found that the vibration of control valve is strongly in low frequency excitation, but high-frequency excitation makes relatively little impacts on it; The diffuser and downstream of valve is the main area of generating vibration.

Abstract: For the purpose of improving the signal processing of single vector hydrophone, this paper combined two velocity signals as two complex data, so as to change array-manifold of single vector hydrophone. Taking two-dimension single vector hydrophone as an example, this paper compared the capability of signal processing of new array-manifold single vector hydrophone with old one from conventional beam-forming(CBF) ,minimum variance distortionless response (MVDR) and multiple signal classification (MUSIC). As for CBF, the analysis indicates, the capability of spatial filtering of new array-manifold could improve 0.51db and the HPBW of new array-manifold will be smaller than old array-manifold. When the noise power is 0, the HPBW of new array-manifold will be narrower than old array-manifold 19.26°. As for MVDR, the capability of signal processing of new array-manifold is the same as old array-manifold. In MUSIC algorithm, the value measuring angle resolution shows the superiority of the new array-manifold- angle resolution. Simulation and measured data proved the better performance of the method presented by this paper.

Abstract: To reduce the noises in received RF signal and improve the performance of RFID system, a novelty denoising method of wavelet transform in RFID system was proposed in this paper. It analyzed wavelet transform method and FFT method,then introduced wavelet transform principle and wavelet coefficients threshold denoising method. According to the standard ISO18000-3,the RF signal at 13.56MHz was simulated using modulation toolbox in LabVIEW environment. At last, the RF signal with Gauss white noise together, was denoised by wavelet transform method and FFT method respectively. Simulation results showed that the wavelet transform denoising method has higher accuracy, better effect, compared with traditional FFT denoising method. The research on application of wavelet analysis in RF signal denoising is significant and practical. The wavelet analysis is applied to the field of virtual instrument, which can provide people with more accurate and convenient testing, and has good application prospects in engineering applications.

Abstract: The aim of this study is to investigate the status in elderly respiratory illness and the impact of air pollution on elderly respiratory health in Jilin during the heating period. A stratified random cluster sampling was used to select 536 elderly living in different districts with different degrees of atmospheric pollution in Jilin as the research objects. The survey on the respiratory diseases and symptoms was conducted with face-to-face retrospective questionnaire survey method, and the data were analyzed with multivariate logistic regression analysis. The results showed that in the heating season in 2012, the major respiratory diseases in elderly of the three districts in Jilin City were acute upper respiratory tract infections, bronchitis and asthma, and the major respiratory symptoms were cough, sputum, wheezing; the severe level order of respiratory diseases and symptoms was inturn Longtan District (an industrial area) > Changyi District (a living area) > Fengman District (a tourist area), and differences in them were statistically significant (P <0.05); residence, opening window for ventilation and smoking were the factors affecting respiratory diseases and symptoms in the elderly. The study indicates that air pollution during the heating period is directly correlated with the elderly respiratory health and the incidence of respiratory diseases should be reduced by changing the heating energy materials, giving up smoking, ventilation and other measures to improve air quality.

Abstract: In the process of the coal gangue hill explosion, a lot of harmful gases can be released, which seriously pollutes the atmospheric environment and is harmful to people’s health; meanwhile, equipments and the surrounding buildings can also be destroyed, which brings huge economic losses and casualties. In addition, social problems caused by coal gangue hills will become a thorny problem for coal enterprises. Therefore, the influencing factors on the coal gangue hill explosion, the explosion characteristics and laws, and the spontaneous combustion process of the coal gangue hill are analyzed; the coal gangue hill explosion are discussed from the arch shell theory, the bottom air leakage and oxygen supply, rainfall, detonating gas explosion, and chain reaction; the conditions, influencing factors and characteristics of the coal gangue hill explosion are obtained.

Abstract: MCF-7 breast cancer cell line was first developed by Dr. Herbert Soule from a pleural effusion taken from a patient with metastatic breast cancer. This estrogen-responsive and estrogen receptor containing cell line can also express androgen, progesterone, glucocorticoid and retinoid receptors. It has been extensively used in identifying environmental estrogens and exploring the toxicity mechanisms, as well as the pathologic study and the disease treatment. This mini review article will focus on the development and application of MCF-7 cells in endocrine-disrupting area, especially in study of environmental estrogens.