Papers by Keyword: Enhancement Factor

Abstract: The enhancement characteristics of carbon nanotubes (CNTs) on CO₂ absorption were investigated experimentally a stirred thermostatic reactor. A comparison of CNTs with micro active carbon was made. From the experimental results, significant enhancement of CO₂ absorption was obtained by both CNTs and micro active carbon, however, different change trends with stirring speed for the two solid particles was observed. With increasing stirring speed, the enhancement factor was decreased in AcC suspensions, whereas in CNT slurries it is increased. The experimental phenomena demonstrated a difference in enhancement mechanism for different size particles. For nanoparticles, besides the grazing effect, the micro-convection caused by Brownian motion should be also taken into account. The micro-convection strengthens the interaction of the concentration field around the particles and thus increases the diffusion rate of the solute. In addition, the agglomeration of the nanoparticle was also an important influencing factor. Due to the agglomeration of the particle, the enhancement factor for CNTs increases initially with increasing stirring speed. A three-dimensional microcosmic mass transfer model was developed to explain the experimental phenomena. Based on the model, the interaction of the flow field around the particles was analyzed.

Abstract: In clinical application, medical images tend to be low contrast, bigger or more speckle noise, and they will affect the effective use of medical images. Medical image enhancement can solve the problem of the low contrast of the image, so as to get more clear details of images. An algorithm of the medical image enhancement is proposed based on the binary wavelet transform in the paper. Firstly, the medical image was carried through dyadic wavelet transform, then the high-frequency information was de-noised, and then to enhance the high frequency information which was de-noised; at last, the enhanced high-frequency sub-images and the low-frequency sub-images were reconstructed by inverse dyadic wavelet transform. Finally, a better visual effect can be got by a subsection grayscale transform. The experiment results show the enhanced effect of proposed method is better than those of the wavelet transform.

Abstract: Based on the basic theory of electromagnetic field, the Electric Field Distortion (EFD) in power frequency electric field caused by induced current of human body has been analyzed. The enhancement factor of the electric field distortion is introduced to reduce the influences caused by human body in the measurement of high voltage electric fields. The Ansoft Maxwell is used to simulate and calculate the electric field distribution under the influence of the human body to have the value of enhancement factor. In addition, the enhancement factor has been corrected by experiment with the electromagnetic field analyzer EFA300. With the enhancement factor introduced in this paper, the measurement error can be reduced.