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21.
Progressive wavelet correlation using Fourier methods 总被引:2,自引:0,他引:2
This paper derives a multiresolution analysis technique for performing correlations on wavelet representations of images. The technique maps the images into the wavelet-frequency domain to take advantage of high-speed correlation in the frequency domain. It builds on Vaidyanathan's (1993) wavelet correlation theorem, which shows that subsamples of correlations of two signals can be obtained from a sum of correlations of subbands of wavelet representations of those signals. Our algorithm produces the correlations at lowest resolution by applying the convolution theorem to subband correlations. A new multiresolution technique fills in the missing correlation data by incrementally inverting the wavelet transform and refining the Fourier transform. When applied to JPEG representations of data, the lowest resolution correlations can he performed directly on the JPEG images to produce 1/64th of the correlation points. Each of three incremental steps quadruple the number of correlation points, and the process can be halted at any point if the intermediate results indicate that the correlation will not find a match 相似文献
22.
Liu X Abd-Elmoniem KZ Stone M Murano EZ Zhuo J Gullapalli RP Prince JL 《IEEE transactions on medical imaging》2012,31(2):326-340
Measuring the 3D motion of muscular tissues, e.g., the heart or the tongue, using magnetic resonance (MR) tagging is typically carried out by interpolating the 2D motion information measured on orthogonal stacks of images. The incompressibility of muscle tissue is an important constraint on the reconstructed motion field and can significantly help to counter the sparsity and incompleteness of the available motion information. Previous methods utilizing this fact produced incompressible motions with limited accuracy. In this paper, we present an incompressible deformation estimation algorithm (IDEA) that reconstructs a dense representation of the 3D displacement field from tagged MR images and the estimated motion field is incompressible to high precision. At each imaged time frame, the tagged images are first processed to determine components of the displacement vector at each pixel relative to the reference time. IDEA then applies a smoothing, divergence-free, vector spline to interpolate velocity fields at intermediate discrete times such that the collection of velocity fields integrate over time to match the observed displacement components. Through this process, IDEA yields a dense estimate of a 3D displacement field that matches our observations and also corresponds to an incompressible motion. The method was validated with both numerical simulation and in vivo human experiments on the heart and the tongue. 相似文献
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CL Gugliucci MJ O''Sullivan W opperman M Gordon ML Stone 《Canadian Metallurgical Quarterly》1976,125(4):435-441
Over the last 2 years at Metropolitan Hospital Medical Center 245 diabetic women have been seen on the obstetric service. This complication of pregnancy comprises 7.9 per cent of 3,076 deliveries, resulting in an over-all uncorrected perinatal mortality rate of 2.9 per cent. We believe that early detection and strict rigid control of diabetes is the key to improved perinatal outcome. This article presents the classification, diagnosis, and management which have led to these results. 相似文献
27.
Examined the effects of instructions and modeling in the reflection-of-feeling training of individuals low in interpersonal-communication skills. Participants with low scores on R. Carkhuff's Communication Index (25 males and 25 females) were randomly assigned by sex to 1 of the 5 training groups so that there were 5 males and 5 females in each group. After viewing videotaped training material, each participant conducted a 15-min interview with a volunteer "client" and completed the Communication Index a second time. Interviews were scored for frequency of reflection-of-feeling responses and level of empathic communication displayed. Analysis of the reflection-of-feeling data indicated that instructions and instructions-plus-modeling were facilitative procedures. Ratings of written and verbal empathy demonstrated the effectiveness of the 2 combined conditions: instructions-plus-modeling and modeling-plus-instructions. Calculation of correlations among scores on criterion measures revealed a positive correlation between reflection-of-feeling scores and ratings of empathic communication. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
KJ Stone 《Canadian Metallurgical Quarterly》1976,157(1):105-109
Potential epidemiological valency (PEV) of the natural foci of tick-borne encephalitis was characterized by the quantity of the infected ticks per unit of the area of the focal territory, and also by the section of the pathway of man's passage along this territory, at which encounter of a single viroforic tick is possible. PEV indices reflected the epidemiological intensity of the natural foci of infection both in the mastered and in the poorly developed areas, and therefore could be used for the epidemiological prognosis on tick-borne encephalitis and in epidemiological search of this infection on the newly-developing territories. The extent of PEV reduction as a result of anti-tick treatment of forests endemic by tick-borne encephalitis which as caricides with a prolonged residual action of the tick-vectors offered a possibility of assessing the epidemiological efficacy of the measures carried out the most objectively. 相似文献
29.
4-(Methoxymethyl)-1,4-cyclohexadiene-1-carboxaldehyde syn-oxime is a new sweetening agent developed by systematic synthesis and taste evaluation of 80 new oximes analogous to the little-used osime sweetener, perillartine. 相似文献
30.
Fourteen women with amenorrhea-galactorrhea were treated with bromo-ergocryptine. Serum prolactin hPRL, hLH, hFSH, estradiol 17-beta (E2), and progesterone values were determined before and during treatment. No consistent pretreatment hormonal pattern was found. During treatment hPRL levels fell in 13 of 14 patients, and E2 rose in 12 of 14 patients. Levels of hLH became normal, and amounts of hFSH did not change. Galactorrhea lessened in all cases and ceased in 11. Menses resumed in 11 patients and 3 women became pregnant. Cessation of galactorrhea and resumption of menses occurred irrespective of initial hPRL or hLH levels. It is suggested that improvement of galactorrhea and resumption of menses in some patients with normal hPRL values are the result of increased serum E2 levels and may be due to a direct action of bromo-ergocryptine on the ovary. Bromo-ergocryptine may also be effective in treatment of amenorrhea, unassociated with galactorrhea or elevated hPRL levels. 相似文献