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21.
One important aspect of assessing the quality in pulp and papermaking is dirt particle counting and classification. Knowing the number and types of dirt particles present in pulp is useful for detecting problems in the production process as early as possible and for fixing them. Since manual quality control is a time-consuming and laborious task, the problem calls for an automated solution using machine vision techniques. However, the ground truth required to train an automated system is difficult to ascertain, since all of the dirt particles should be manually segmented and classified based on image information. This paper proposes a framework for developing and tuning dirt particle detection and classification systems. To avoid manual annotation, dry pulp sheets with a single dirt type in each were exploited to generate semisynthetic images with the ground truth information. To classify the dirt particles, a set of features were computed for each image segment. Sequential feature selection was employed to determine a close-to-optimal set of features to be used in classification. The framework was tested both with semisynthetically generated images based on real pulp sheets and with independent original real pulp sheets without any generation. The results of the experiments show that the semisynthetic procedure does not significantly change the properties of images and has little effect on the particle segmentation. The feature selection proved to be important when the number of dirt classes changes since it allows to improve the classification results. Using the standard classification methods, it is possible to obtain satisfactory results, although the methods modeling the data, such as the Bayesian classifier using the Gaussian Mixture Model, show better performance.  相似文献   
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A micropump based on strong polarization of ion-exchange beads and corresponding actuation by electroosmosis of the second kind was designed and fabricated. Experimental results from operation with AC and DC voltage showed a close to second order relationship between flow and voltage, in good agreement with theory. The difference between experimental and theoretical flow rates and pressures is attributed to the hydrodynamic resistance of the channel network. A modified pump design which should yield higher flow rates and pressures was suggested.  相似文献   
24.
Nanocrystalline titania particles doped with ruthenium oxide have been prepared by homogenous hydrolysis of TiOSO4 in aqueous solutions in the presence of urea. The synthesized particles were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and surface area (BET) and porosity determination (BJH). The photocatalytic activity of Ru-doped titania samples was determined in the gas phase by decomposition of acetone during irradiation at 365 nm and 400 nm. The Ru-doped titania samples demonstrated enhanced photocatalytic activity under visible light. Ruthenium oxide causes the anatase to rutile transformation to occur at lower temperatures and decreasing of band-gap energy of Ru-doped samples.  相似文献   
25.
A method is described for preparing hydroxyapatite strengthened with a glass phase. The properties of the composites obtained containing both biological and synthetic hydroxyapatite are studied. Characteristics of the test materials such as pycnometric density, volumetric porosity, biological solubility, and mechanical strength are determined.  相似文献   
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We report a novel hybrid charge sensor realized by the deposition of phospholipid monolayers on highly doped n‐GaN electrodes. To detect the binding of recombinant proteins with histidine‐tags, lipid vesicles containing chelator lipids were deposited on GaN electrodes pre‐coated with octadecyltrimethoxysilane monolayers. Owing to its optical transparency, GaN allows the confirmation of the fluidity of supported membranes by fluorescence recovery after photo‐bleaching (FRAP). The electrolyte‐(organic) insulator‐semiconductor (EIS) setup enables one to transduce variations in the surface charge density ΔQ into a change in the interface capacitance ΔC p and, thus, the flat‐band potential ΔU FB. The obtained results demonstrate that the membrane‐based charge sensor can reach a high sensitivity to detect reversible changes in the surface charge density on the membranes by the formation of chelator complexes, docking of eGFP with histidine tags, and cancellation by EDTA. The achievable resolution of ΔQ ≥ 0.1 μC/cm2 is better than that obtained for membrane‐functionalized p‐GaAs, 0.9 μC/cm2, and for ITO coated with a polymer supported lipid monolayer, 2.2 μC/cm2. Moreover, we examined the potential application of optically active InGaN/GaN quantum dot structures, for the detection of changes in the surface potential from the photoluminescence signals measured at room temperature.  相似文献   
28.
The study was conducted to report on the use of molecular biology methods and pregnancy outcome in women sensitized to either Rhesus D (RhD) or Kell 1 (K1) antigens. Paternal RhD genotype was determined by DNA amplification of an RhD-specific sequence from single sperm cells. Paternal Kell phenotype was determined by serologic assays using peripheral blood samples, and the fetal RhD or Kell-type status were established by the polymerase chain reaction (PCR) with amniotic cells. Thirteen women (14 pregnancies, one with twins) sensitized to RhD and four sensitized to K1 antigens, comprised the study group. All had paternal heterozygosity to either D or K1 antigens. Nine fetuses were RhD positive and five were RhD negative. An additional woman underwent early spontaneous abortion. The nine RhD-positive fetuses underwent a total of 41 invasive procedures. One fetus with hydrops fetalis died in utero after intrauterine blood transfusion. All the remaining RhD-positive fetuses were delivered after 33 weeks gestation, and all those who were RhD negative were delivered at term. Four women were sensitized to the K1 antigen; in three, the fetus was found to be K1 negative, and in one, K1 positive, necessitating intrauterine blood transfusion. In all cases, the results of RhD or K1 genotype analyses from amniotic fluid were compatible with fetal/neonatal red blood cell RhD or Kell phenotypes. In conclusion, the use of molecular biology techniques represents a major advance in the clinical management of RhD and Kell alloimmunization.  相似文献   
29.
The transmission of ultrashort optical pulses over long distances in optical fibers is limited by pulse broadening due to group velocity dispersion. A grating and telescope dispersion compensator with group velocity dispersion of equal magnitude and opposite sign can compensate for the fiber dispersion. The possible benefits of such dispersion compensation in the 1.3-1.6-μm wavelength region are investigated. The results show that compensation of first-order dispersion at 1.55 μm in a fiber with zero dispersion near 1.3 μm is primarily limited by the second-order dispersion of the grating and the telescope compensator. For a wavelength slightly greater than the zero dispersion wavelength, both the first- and second-order group velocity dispersion can be canceled by the grating and telescope dispersion compensator, allowing transmission exceeding 100 Gb/s over 100 km  相似文献   
30.
Monoclonal antibodies 6C6 and 10D5 raised against the N-terminal of beta-amyloid peptide interfere with the formation of beta-amyloid and trigger reversal to its non-toxic components. The epitopes of these antibodies were localized employing a library composed of filamentous phage displaying random combinatorial hexapeptides. Among 44 positive phage-clones, selected from the library by both antibodies, 40 clones carried the consensus sequence EFRH. These EFRH phage-clones bind specifically mAbs 6C6 or 10D5 with an apparent binding constant of approximately 10(-9) M. The peptide EFRH inhibits binding of mAbs 6C6 or 10D5 to beta-amyloid peptide in affinities identical to those obtained. with the peptides corresponding to positions 1-9, 1-16 and 1-40 of beta-peptide. These findings confirm that the peptide EFRH which is located at positions 3-6 within beta-amyloid peptide represents the sequential epitope of mAbs 6C6 and 10D5.  相似文献   
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