Abstract: A panoramic image stitching method includes acquiring a plurality of first images, converting camera image plane coordinates of each first image of the plurality of first images into virtual image plane coordinates for generating a second image according a world coordinate system, identifying a plurality of feature points on the second image, calibrating coordinates of the plurality of feature points on the second image, generating a calibrated second image according to calibrated coordinates of the plurality of feature points on the second image, and stitching a plurality of calibrated second images for generating a panoramic image.

Abstract: A polyesterification method comprises steps of mixing, by combining N,N-dialkylformamide dialkyl acetal with a tin catalyst, so as to transfer an alkoxy group from the N,N-dialkylformamide dialkyl acetal to the tin catalyst to obtain a Sn coordination complex; and polymerization, by conducting a ring-opening polymerization of a ester under the catalysis of the Sn coordination complex, and finally to obtain a polyester compound; wherein, the chemical formula of the N,N-dialkylformamide dialkyl acetal is (RO)2CHNR2, with the R being an alkyl group.

Abstract: A polyesterification method comprises steps of mixing, by combining N,N-dialkylformamide dialkyl acetal with a tin catalyst, so as to transfer an alkoxy group from the N,N-dialkylformamide dialkyl acetal to the tin catalyst to obtain a Sn coordination complex; and polymerization, by conducting a ring-opening polymerization of a ester under the catalysis of the Sn coordination complex, and finally to obtain a polyester compound; wherein, the chemical formula of the N,N-dialkylformamide dialkyl acetal is (RO)2CHNR2, with the R being an alkyl group.