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101.
This paper presents an approach of measuring in real-time the vector of finger that is pointing to an object. DSP is used in the operation processing unit in order to do the real-time processing. The steps include the extraction of flesh-colored regions from an image, the labeling of the flesh-colored regions, and the detection of two characteristic positions on the finger so that the direction that the finger is pointing at will be calculated. The entire process takes about 29 msec, which makes it possible to have the frame rate of 34 fps. With this frame rate, this measurement approach is considered real-time and promising to be merged into other application systems. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
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105.
Visibility of collaboration on the Web   总被引:14,自引:3,他引:11  
The emerging influence of new information and communication technologies (ICT) on collaboration in science and technology has to be considered. In particular, the question of the extent to which collaboration in science and in technology is visible on the Web needs examining. Thus the purpose of this study is to examine whether broadly similar results would occur if solely Web data was used rather than all available bibliometric co-authorship data. For this purpose a new approach of Web visibility indicators of collaboration is examined. The ensemble of COLLNET members is used to compare co-authorship patterns in traditional bibliometric databases and the network visible on the Web. One of the general empirical results is a high percentage (78%) of all bibliographic multi- authored publications become visible through search of engines in the Web. One of the special studies has shown Web visibility of collaboration is dependent on the type of bibliographic multi-authored papers. The social network analysis (SNA) is applied to comparisons between bibliographic and Web collaboration networks. Structure formation processes in bibliographic and Web networks are studied. The research question posed is to which extent collaboration structures visible in the Web change their shape in the same way as bibliographic collaboration networks over time. A number of special types of changes in bibliographic and Web structures are explained. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
106.
The difference in the turbulent diffusion between the active (heat) and passive (mass) scalars in a thermally stably stratified medium is investigated. The axisymmetric problem is treated on the formation of a turbulent circulation flow above a heated disk and on the turbulent diffusion of a passive scalar (impurity) from a continuous surface source in a stably stratified medium. The results indicate that the thermal stratification causes appreciable differences in the coefficients of turbulent transfer between the active (heat) and passive (mass) scalars. This means that the assumption of the identity of the coefficient of turbulent diffusion of heat and mass, employed in conventional models of turbulence, produces significant errors in estimating the heat and mass transfer in a thermally stably stratified medium.  相似文献   
107.
Thermal Transformations of an Aluminoborophosphate Binder   总被引:1,自引:0,他引:1  
Thermal transformations of a commercial aluminoborophosphate binder are studied in a broad temperature range by optical microscopy, x-ray diffraction, IR spectroscopy, and thermal analysis. The introduction of B2O3 reduces the temperature of phosphate polycondensation, enhances the stability of cyclometaphosphates in a broad temperature range (180–1100°C), and reduces the stability of hydrogen phosphates.  相似文献   
108.
Some of the factors affecting cloud point determination of palm oleins are described. These are the type of container used, method of stirring, rate of stirring and bath temperature. The repeatability and reproducibility standard deviations of the method are determined from collaborative trials. Recommendations for the test are made to reduce the large variations among laboratories.  相似文献   
109.
A method is developed, based on word-searching, which provides a rapid test for the statistical significance of DNA sequence similarities for use in databank searching. The method makes allowance for the lengths and dinucleotide compositions of the sequences being compared. A way is also described to calculate the power of the test, i.e. the probability of detecting a given similarity as being statistically significant. The effects on the power of the test of the scoring method, word length, sequence length, and sequence composition are examined. A novel scoring method is shown to be superior to the method currently used in most word-searching algorithms.  相似文献   
110.
Ellagic acid (2, 3, 7, 8‐tetrahydroxy(1)benzopyrano(5, 4, 3‐cde)(1)benzopyran‐5, 10‐dione) was selected as a model pollutant which is present in the tannic fraction of cork processing wastewater. The ultrafiltration of aqueous ellagic acid solutions through three membranes was studied in tangential UF laboratory equipment. Two of the membranes were polyethersulfone (Biomax10K and Biomax5K, with MWCO of 10000 and 5000 Da, respectively), and the third made of regenerated cellulose (Ultracel5K, with MWCO of 5000 Da). The water hydraulic permeability was evaluated for each membrane. The evolution of the permeate flow rate with processing time was followed, and the influence of the main operating variables (feed flow rate, trans‐membrane pressure and nature of the membranes) on the permeate flux was also established. According to the hypothesis of the film theory, the intrinsic and apparent rejection coefficients, as well as the mass transfer coefficients, were also determined, and the values obtained were discussed as a function of the operating conditions used.  相似文献   
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