Log polar transformation is an important algorithm of space-variant vision theory.It well depicts the retino-cortical mapping.Due to the logarithmic and the arctangent operation in the transformation,the log polar coo...Log polar transformation is an important algorithm of space-variant vision theory.It well depicts the retino-cortical mapping.Due to the logarithmic and the arctangent operation in the transformation,the log polar coordinate of an image is mostly a decimal fraction and the range is quite narrow.Aiming at solving these problems,this paper puts forward an inverse log polar transformation based on sub-pixel interpolation.The acquired log polar image of the new algorithm has no mosaic phenomenon,meanwhile it is a better simulation of retina-cortical mapping.展开更多
According to the characteristics of high-order solitons,compressed picosecond pulses are numerically simulated in the photonic crystal fiber (PCF),by means of split-step Fourier method. The results show that,PCF enabl...According to the characteristics of high-order solitons,compressed picosecond pulses are numerically simulated in the photonic crystal fiber (PCF),by means of split-step Fourier method. The results show that,PCF enables input pulse with lower peak power to form high-order solitons for the purpose of femtosecond pulse-width compression. For example,60- femtosecond pulse width was made for 1-ps initial pulse width only over the distance of 2.2 m.Besides,shorter optimum fiber length for compression and higher compression ratio could be obtained on the premise of pre-chirp technique.展开更多
The topic of this essay is that effective businees communication requires effective practices.This essay will focus on communication practices that can assist an organi- zation in reaching its strategic goals and obje...The topic of this essay is that effective businees communication requires effective practices.This essay will focus on communication practices that can assist an organi- zation in reaching its strategic goals and objectives.This article will present this topic by analyzing the communication theory, writing process and business writing style, team building and interpersonal communication, negotiation and persuasion tech- niques and intercultural communication.展开更多
基金Supported by the National Natural Science Foundation of China(grant No.60575013)
文摘Log polar transformation is an important algorithm of space-variant vision theory.It well depicts the retino-cortical mapping.Due to the logarithmic and the arctangent operation in the transformation,the log polar coordinate of an image is mostly a decimal fraction and the range is quite narrow.Aiming at solving these problems,this paper puts forward an inverse log polar transformation based on sub-pixel interpolation.The acquired log polar image of the new algorithm has no mosaic phenomenon,meanwhile it is a better simulation of retina-cortical mapping.
文摘According to the characteristics of high-order solitons,compressed picosecond pulses are numerically simulated in the photonic crystal fiber (PCF),by means of split-step Fourier method. The results show that,PCF enables input pulse with lower peak power to form high-order solitons for the purpose of femtosecond pulse-width compression. For example,60- femtosecond pulse width was made for 1-ps initial pulse width only over the distance of 2.2 m.Besides,shorter optimum fiber length for compression and higher compression ratio could be obtained on the premise of pre-chirp technique.
文摘The topic of this essay is that effective businees communication requires effective practices.This essay will focus on communication practices that can assist an organi- zation in reaching its strategic goals and objectives.This article will present this topic by analyzing the communication theory, writing process and business writing style, team building and interpersonal communication, negotiation and persuasion tech- niques and intercultural communication.
