Maximum entropy signal processing of two-dimensional NMR data

1985 ◽  
Vol 64 (3) ◽  
pp. 436-440 ◽  
Author(s):  
Jeffrey C Hoch
Author(s):  
Wei Liu ◽  
Shuai Yang ◽  
Zhiwei Ye ◽  
Qian Huang ◽  
Yongkun Huang

Threshold segmentation has been widely used in recent years due to its simplicity and efficiency. The method of segmenting images by the two-dimensional maximum entropy is a species of the useful technique of threshold segmentation. However, the efficiency and stability of this technique are still not ideal and the traditional search algorithm cannot meet the needs of engineering problems. To mitigate the above problem, swarm intelligent optimization algorithms have been employed in this field for searching the optimal threshold vector. An effective technique of lightning attachment procedure optimization (LAPO) algorithm based on a two-dimensional maximum entropy criterion is offered in this paper, and besides, a chaotic strategy is embedded into LAPO to develop a new algorithm named CLAPO. In order to confirm the benefits of the method proposed in this paper, the other seven kinds of competitive algorithms, such as Ant–lion Optimizer (ALO) and Grasshopper Optimization Algorithm (GOA), are compared. Experiments are conducted on four different kinds of images and the simulation results are presented in several indexes (such as computational time, maximum fitness, average fitness, variance of fitness and other indexes) at different threshold levels for each test image. By scrutinizing the results of the experiment, the superiority of the introduced method is demonstrated, which can meet the needs of image segmentation excellently.


2011 ◽  
Vol 23 (7) ◽  
pp. 075104 ◽  
Author(s):  
D. C. Montgomery ◽  
W. H. Matthaeus

1991 ◽  
Vol 30 (20) ◽  
pp. 2879 ◽  
Author(s):  
Suganda Jutamulia ◽  
George M. Storti ◽  
Joseph Lindmayer ◽  
William Seiderman

Author(s):  
Chjuo Fuguan ◽  
Seesregdorj S ◽  
Gerelt-Od Ya

The four sesquiterpenes calameone (1), dehydrocostus lactone (2), aristolone (3), alantolactone (4) and one triterpenoid α-amyrine (5), simple phenolic compounds such as 4-hydroxybenzaldehyde, (6), piceol (7), apocynin (8), dihydroconiferyl (9) and coniferyl (10) have been identified by using the proton and carbon NMR spectra which were isolated from a dichloromethane extract of the roots of Aucklandia lappa Decne. Their structures were established by the one‐and two‐dimensional NMR techniques including DEPT, COSY and HMBC spectroscopy. This work examined proton and carbon NMR data of calameone (1) and aristolone (3) for the first time, which had not yet been fully studied in previous literature. Рүда ургамлын (Aucklandia lappa Decne.) терпент нэгдлийн судалгаа Хураангуй: Рүда ургамлын үндэсний дихлорметаны ханднаас хроматографийн аргуудаар эвдесман хэлбэрийн сесквитерпен каламеон (1), аристолон (3), алантолактон (4), гвяан хэлбэрийн сесквитерпен дегидрокостасын лактон (2), тритерпеноид α-амурин (5) болон энгийн фенолт нэгдэл 4-гидроксибензальдегид (6), пицелол (7), апоцинин (8), дегидрокониферол (9), кониферол (10) зэрэг бодисыг химийн цэвэр байдалтай ялгав. Эдгээр бодисын бүтэц байгуулалтыг нэг болон хоёр хэмжээст ЦСР-ын DEPT, COSY, HMBC спектроскопийн аргаар таньж тодорхойлов. Урьд өмнө каламеон (1), аристолон (3) бодисуудын устөрөгч ба нүүрстөрөгчийн атомуудын химийн шилжилтийн утгуудад оноолт бүрэн хийгдээгүй байсан ба энэ хоёр бодисын оноолтыг гүйцээж хийв. Түлхүүр үг: Терпеноид, сесквитерпент лактон, дегидрокостасын лактон, ЦСР.


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