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31.
Ching-Liang Su 《Journal of Intelligent and Robotic Systems》2006,45(1):1-14
This research uses the object extracting technique to extract the index, middle and ring fingers from the hand images. The algorithm developed in this research can find the precise locations of the different fingers' fingertips and the finger-to-finger-valleys. After finding the positions of the fingertips and finger-valleys, the index, middle and ring fingers can be extracted from the hand images by using morphological technique. The extracted index, middle and ring fingers contain many useful geometry features. One can use these features to do the person's identification. The orientations of the index, middle and ring fingers are found in this research. Image rotating, image shifting, and image interpolating techniques are used to align different persons' index, middle and ring fingers. Image subtraction is used to exam the difference of two index, middle and ring finger images. In this research so far only use the index, middle and the ring fingers as the features to identify different persons.
★This work was supported by National Science Council under grant NSC 93-2213-E-212-011. 相似文献
32.
3D characterization and analysis of particle shape using X-ray microtomography (XMT) 总被引:2,自引:0,他引:2
C.L. Lin 《Powder Technology》2005,154(1):61-69
33.
Dongchang Sun Liyong Tong 《International journal for numerical methods in engineering》2004,60(11):1911-1932
A novel finite element model is presented for static and dynamic analysis of composite plates integrated with a laminated piezoelectric layer, a host laminated composite plate and an adhesive layer between them. A new adhesive element is developed which includes both peel and shear effects in the adhesive layer based on first‐order shear deformation plate theory. The thin adhesive layer between the piezoelectric layer and the host plate is modelled by assuming that it carries constant shear and peel strains throughout its thickness. In addition, a weighted static shape control scheme for finding the optimal voltage distribution for static shape control is given. By selecting different weighting matrices, a variety of items such as displacements, slopes, curvatures, strains and even generalized forces, can be included in finding the optimal actuating voltage for static shape control. The present model is validated by comparing with those results available in the literature. The numerical results show that the weighted linear least method can give a satisfactory voltage distribution to best match the desired shape. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
34.
Bedich ika Helena Bendov Ivan Macha
《Chemical Engineering and Processing: Process Intensification》2005,44(12):1312-1319
A procedure has been proposed for the estimation of the terminal falling velocity of non-spherical particles moving in a Carreau model fluid in the transition flow region. The procedure is based on a modification of the relationship formerly developed for the fall of spherical particles including the particle dynamic shape factor. The suitability of the proposed procedure has been confirmed by good agreement between experimental and calculated terminal falling velocity data. In the experiments, the terminal falling velocity of short cylinders and rectangular prisms in polymer solutions of different measure of shear thinning and elasticity has been measured. 相似文献
35.
36.
37.
M. Guerioune Y. Amiour W. Bounour O. Guellati A. Benaldjia A. Amara N. E. Chakri M. Ali-Rachedi D. Vrel 《International Journal of Self-Propagating High-Temperature Synthesis》2008,17(1):41-48
Aiming at preparation of shape memory alloys (SMAs), we explored the SHS of Cu1 − x
Zn1 − y
Al1 − z
alloys (0.29 < x < 0.30, 0.74 < y < 0.75, and 0.83 < z < 0.96). The most pronounced shape memory effect was exhibited by the alloys of the following compositions (wt %): (1) Cu(70.6)Zn(25.4)Al(4.0),
(2) Cu(70.1)Zn(25.9)Al(4.0), and (3) Cu(69.9)Zn(26.1)Al(4.0). The effect of process parameters on the synthesis of CuZnAl
alloys was studied by XRD, optical microscopy, and scanning electron microscopy (SEM). The grain size of CuZnAl was found
to depend on the relative amount of the primary CuZn and AlZn phases. Changes in the transformation temperature and heat of
transformation are discussed in terms of ignition intensity and compaction. Mechanism of the process depends on the level
of the temperature attained relative to the melting point of components. At the melting point of AlZn, the process is controlled
by the solid-state diffusion of AlZn into a product layer. The ignition temperature for this system depends on the temperature
of the austenite-martensite transformation in CuZnAl alloys. The composition and structure of the products was found to markedly
depend on process parameters. The SHS technique has been successfully used to prepare a variety of SMAs.
相似文献
38.
Hatto F. Jacobi 《国际钢铁研究》2003,74(11-12):667-678
Improvements of solidification processing in conventional or near net shape casting depend on sophisticated methods of macroscopic examination of central unsoundness and inhomogeneity of the cast material. As long as remarkable deviations referring to the quality features exist between the slab centre and the bulk material such methods should be looked after. Two semi‐macroscopic methods of segregation analysis are discussed in this paper: firstly, the potential of the emission spectral analysis combined with sectioning of a sample and secondly, the computer aided micro‐probe analysis. Both methods are restricted to small local areas. The proneness of elements and steel grades with respect to micro‐ and macrosegregation as well as distribution‐ and segregation coefficients are determined. The effect of a diffusion anneal on homogenisation of segregation is studied. Last not least the precipitation of sulphides, phosphides or carbonitrides is estimated. Ultrasonic detection of the central unsoundness of conventional slabs or thin slabs is a new approach towards a quantitative macroscopic examination. The sample size is 400 mm x 300 mm x 30 mm. To achieve a low ultrasonic noise using a 5 MHz‐transducer the samples are heat treated for grain refinement. “Dog bone porosity”, macroscopic topographical misfit between the upper and lower solidifying shells, periodical corner cracks or systematic transverse centre cracks are detected. Obviously, segregations do not reflect the ultrasonic beam. However, it can be presumed that an interrelation exists between porosity and segregation, although these might be locally apart from each other. This new ultrasonic test of the central unsoundness of continuous cast (c.c.) slabs gives valuable arguments to machine builders and maintenance people to decide on the right concepts for strand guidance, support rollers and secondary cooling. Soft reduction can be optimized and variations in casting speed counteracted by dynamic means. R&D service of this kind can help steelmakers when decisions are impending to build new casting machines or revamp old ones. 相似文献
39.
Four experiments investigated the effect of recent selective practice on the cost of switching between 2 tasks afforded by letter-digit pairs: alphabet arithmetic and shape comparison. Experiments 1 and 2 found a greater cost associated with switching to the more recently practiced task: evidence that task-set inertia contributes to switching costs. Experiment 3 found this effect to be limited to trials on which a recently trained stimulus followed another such stimulus: a result problematic for all current theories of task-set priming. Experiment 4 showed that the effect of recent practice was eliminated by active preparation for a task switch: It appears that endogenous task-set preparation reduces the effects of task-set inertia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
万家寨大坝外部变形控制网综述 总被引:1,自引:1,他引:0
结合万家寨水利枢纽大坝外部变形控制网测量项目 ,从控制网的布设、标点建造、观测、数据处理及成果分析等方面进行了介绍。实际观测结果说明 ,该控制网能够准确反映大坝运行状态 ,满足工程安全运行需要 相似文献