Biomedical subjects

G Y Dong

Publications and source records attributed to G Y Dong.

4 recordsLinked to original sources

PubMed2006

Fast blind extraction of arbitrary unknown phase shifts by an iterative tangent approach in generalized phase-shifting interferometry.

A novel fast convergent algorithm to extract arbitrary unknown phase shifts in generalized phase-shifting interferometry (PSI) is proposed and verified by a series of computer simulations. In this algorithm an error function is introduced and then the unknown phase shifts are found by an iterative tangent approach. In combination with the statistical method, this algorithm can give the most exact results in the fewest iteration steps. It can be used for generalized PSI of arbitrary frames for both smooth and diffusing objects and can usually reach the exact phase shifts with only four or five iterations for three- or four-frame PSI.

Journal Article↗

PubMed2006

Two-step phase-shifting interferometry and its application in image encryption.

Conventional phase-shifting interferometry (PSI) needs at least three interferograms. A novel algorithm of two-step PSI, with an arbitrary known phase step, by which a complex object field can be reconstructed with only two interferograms is proposed. This algorithm is then applied to an information security system based on double random-phase encoding in the Fresnel domain. The feasibility of this method and its robustness against occlusion and additional noise attacks are verified by computer simulations. This approach can considerably improve the efficiency of data transmission and is very suitable for Internet use.

Journal Article↗

PubMed2001

[Studies on chemical constitutents from Penthorum chinense Pursh].

OBJECTIVE: To study the chemical constituents of Penthorum chinense. METHOD: Silica gel and macroporous resin were used as adsorbent for isolation and purification. The chemical structures were elucidated by spectral analysis and chemical methods. RESULT: Three compounds were isolated from the water-extract of P. chinense. The structures were identified as 5-hydroxy-flavanone-7-O-beta-D-glucoside (I), 2,4,6-trihydroxybenzoic acid (II) and quercetin(III), respectively. CONCLUSION: Compounds I and II were isolated from this plant for the first time.

Flavanones↗

PubMed1990

[Quantitative Chinese pharmaceutical study on children pneumonia treated by Pu fu-zhou].

By method of quantitative Chinese pharmacy, the author studied the children pneumonia cases recorded in two books, "Pu Fuzhou's Medical Cases" and "Pu Fuzhou's Medical Experiences". The rule of Chinese medicine used by Pu Fuzhou was probed preliminarily. It was a characteristic that Pu Fuzhou treated the children pneumonia cases by using Pinelliae Tuber, Exocarpium Citri Rubrum, Jujube and Radix Glycyrrhizae. But the rate of using Herba Lophatherum was less in pneumonia group than in non-pneumonia (contrast) group. According to the rate of overdose prescriptions, 11 Chinese herbal medicines used frequently in pneumonia group were classified into 4 sections. Only overdosage rate of section B (Radix Glycyrrhizae and Peucedanum Decursivum Maxim) was correlated with various kinds of diseases. Referring to the compatibility of dosage of the two Chinese medicines used, there were positive correlation in 35 of 38 pairs, among them, P less than 0.05 in 20; negative correlation in 3 of 38 pairs, among them, P less than 0.05 in 1. It was revealed that in 18 of 38 pairs, in which no significant positive correlation was present, the dosages of Chinese medicine used by Dr. Pu varied with different degree of severity and kind of symptoms he treated.

Child↗