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51.
Knowledge-based 3D analysis from 2D medical images   总被引:1,自引:0,他引:1  
An anatomical knowledge-based system for image analysis that interprets CT/MR (computed tomography/magnetic resonance) images of the human chest cavity is reported. The approach utilizes a low-level image analysis system with the ability to analyze the data in bottom-up (or data-driven) and top-down (or model-driven) modes to improve the high-level recognition process. Several image segmentation algorithms, including K-means clustering, pyramid-based region extraction, and rule-based merging, are used for obtaining the segmented regions. To obtain a reasonable number of well-segmented regions that have a good correlation with the anatomy, a priori knowledge in the form of masks is used to guide the segmentation process. Segmentation of the brain is also considered.  相似文献   
52.
G. K. Dhawan 《Acta Mechanica》1981,39(1-2):145-151
Conclusions The curves of normal displacementu z (r, 0) (Fig. 2) in the presence of adhesion coincide approximately with the dashed line. The contact pressure zz(r,0) in the presence of adhesion is slightly larger than the one without friction. Thus,u z(r,0) and zz(r,0) in the actual condition can be evaluated approximately by the results without friction.With 3 Figures  相似文献   
53.
Authors' reply     
The comment of Stig Steenstrup on the use of gray level entropy function in our paper' has been addressed. The entropy measure has not been used in the procedure of enhancement, but it has only been used to show statistically that the enhanced images have larger gray level entropy, and therefore better utilize the gray levels.  相似文献   
54.
In continuation of our earlier work on the electrochemical behaviour of amino acids and their metal complexes [1–3], the present investigation reports the polarographic behaviour of Cd(II) and Pb(II) in presence of DL-norleucine, formation and composition of their complexes, determination of stability constants by DE FORD and HUME'S method [4] and MIHALLOV'S mathematical approach [5] at 20° and 30°C and also thermodynamic parameters accompanying complexation reactions at 20°C.  相似文献   
55.
This paper points out some technical errors in the derivation of main results in the above paper and present the results in corrected form.  相似文献   
56.
Biofiltration is a process in which an otherwise conventional granular filter is designed to remove not only fine particulates but also dissolved organic compounds through microbial degradation. Biofiltration can reduce the need for chemicals in drinking water treatment and thus improved applications of biofiltration in drinking water treatment can be viewed as green or sustainable engineering technology. Recent trends in biofiltration technology for drinking water treatment have or have attempted to extend the performance of biofilters through gaining a better understanding of operational constraints. This review articles summarizes important operational parameters influencing biofiltration performance such as hydraulic loading, empty bed contact time (EBCT), temperature, media type, and backwashing conditions. In addition, recent advancements in biofiltration operations including, ozonation, ammonia removal and the influence of nutrient (nitrogen, phosphorous) supplementation to facilitate carbon removal are explored. ? 2015 Society of Chemical Industry  相似文献   
57.
58.
This paper presents the corrosion inhibition performance of soluble self-doped copolymers of aniline and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid synthesized by chemical oxidative polymerization method. The corrosion inhibition behaviour of the copolymers in 1.0 M HCl has been evaluated using Tafel Extrapolation method and electrochemical impedance spectroscopy (EIS) which was also used to propose the mechanism besides surface morphology. The results showed that the copolymer film exhibited the significant shifting in the corrosion potential and greater charge transfer resistance. The corrosion inhibition efficiency was found to increase from 50% to 90% by increasing the concentration of copolymer from 10 to 70 mg/l in HCl medium. Moreover, the copolymer showed the larger degree of surface coverage onto the iron surface, reflecting the higher inhibition for corrosion of the iron in highly acidic medium.  相似文献   
59.
We have developed and tested a 4 channel, 500 MHz, 512 k sample, 8 bit waveform digitizer in a FASTCAMAC module. A novel feature is the implementation of a sparse scan during readout with a programmable differential trigger to reduce the data to a manageable level. The differential trigger allows reliable detection of pulses with low threshold in the presence of a variable baseline.  相似文献   
60.
Copolyperoxides of 2-(acetoacetoxy)ethyl methacrylate (AEMA) with styrene (St) and methyl methacrylate (MMA) of different compositions have been synthesized in the presence of 2,2′-azobisisobutyronitrile as a free radical initiator under 100 psi oxygen pressure at 50 °C. The rates of oxidative copolymerization reactions are determined from the oxygen consumption (Δp) against time plot. Highly exothermic thermal degradations of these copolyperoxides are studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) and degradation products have been characterised by electron-impact mass spectroscopy (EI-MS). The NMR spectroscopy and EI-MS analysis confirm the alternating peroxy bonds in the main chain. The monomer reactivity ratios are computed by the Fineman–Ross and Kelen–Tüdös methods, using compositions obtained from 1H and 13C NMR analysis. These copolymers can potentially be used as polymeric initiators for the radical polymerization of vinyl monomers, autocombustible fuel. Also, the β-carbonyl moieties along the side chain of the copolyperoxides can be utilized to prepare degradable polyperoxide–metal complexes.  相似文献   
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