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1.
Skin detection is a difficult and primary task in many image processing applications. Because of the diversity of various
image processing tasks, there exists no optimum method that can perform properly for all applications. In this paper, we have
proposed a novel skin detection algorithm that combines color and texture information of skin with cellular learning automata
to detect skin-like regions in color images. Skin color regions are first detected, by using a committee structure, from among
several explicit boundary skin models. Detected skin-color regions are then fed to a texture analyzer which extracts texture
features via their color statistical properties and maps them to a skin probability map. This map is then used by cellular
learning automata to adaptively make a decision on skin regions. Conducted experiments show that the proposed algorithm achieves
the true positive rate of about 86.3% and the false positive rate of about 9.2% on Compaq skin database which shows its efficiency. 相似文献
2.
Mohammad Mohammadi Ahmad Ramazani SaadatAbadi Shohreh Mashayekhan Reza Sanaei 《应用聚合物科学杂志》2020,137(40):49219
Peripheral nerve injuries remain among the most challenging medical issues despite numerous efforts to devise methods in fabrication of nerve conduits to functionally regenerate axonal defects. In this regard, the current study offers a holistic perspective in design by considering the mechanical, topographical and structural aspects which are crucial for a successful nerve guide conduit. Poly(e-caprolactone) and gelatin were employed to serve this purpose in the form of dual-electrospun films which were rolled and later shaped the assembly of a multichannel conduit. Polyaniline/graphene (PAG) nanocomposite was incorporated to endow the conduit with conductive properties. FTIR analysis, water contact angle measurements, and SEM observations as well as mechanical and conductivity tests were used to evaluate the properties of the conduits. In addition, MTT assay was conducted to assess the proliferation of rat bone marrow-derived mesenchymal stem cells cultured on the films. Incorporating 2% PAG proved to have superior cell support and proliferation, while guaranteeing electrical conductivity of 10.8 × 10−5 S/cm and remarkable tensile strength of 3.52 ± 1.3 MPa and 14.12 ± 3.1 MPa for wet and dry conditions, respectively. Overall, the observed results highlight the great potential of the fabricated conduit to be used as a candidate for peripheral nerve defects. 相似文献
3.
Pari Mirahmadpour Davood Nematollahi Mohammad Hossein Banitaba Saied Saeed Hosseiny Davarani 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(2):376-383
Electrochemical synthesis of coordination polymers of Cu(II), [Cu(TDA)]n and [Cu2(BTC)(H2O)6?6H2O]n in which H2TDA is 2,2′-thiodiacetic acid and BTC stands for 1,2,4,5-benzenetetracarboxylate was carried out by the electrochemical oxidation of Cu anode in the presence of H2TDA (a flexible ligand), and 1,2,4,5-benzentetracarboxylic acid (H4BTC) (a rigid ligand) in aqueous solutions. The structure of coordination polymers were characterized by scanning electron microscopy, X-ray powder diffraction, elemental analysis, thermal gravimetric and differential thermal analyses. The crystal structure of the compounds consists of one-dimensional cubical crystal polymeric units of [Cu(TDA)]n and [Cu2(BTC)(H2O)6?6H2O]n. Furthermore, the coordination number of Cu (II) ions in synthesized coordination polymers to be found five. The main advantages of electrosynthesis are the minor synthesis time, the milder conditions and the facile synthesis of coordination polymer coatings. 相似文献
4.
Polyurethane-urea (PUU) nanocomposite membranes have been prepared using various loadings of silica (SiO2) nanoparticles. A Novel PU was fabricated by a two-step bulk polymerization technique based on polycaprolactone (PCL), hexamethylene diisocyanate (HDI), and diamine chain extender, 4,4-methylenebis(2-chloroaniline) (MOCA). The FTIR spectra indicated that the extent of phase separation reduces with increasing SiO2 content. The presence of crystal regions in the soft and hard segments was confirmed by DSC and XRD analyses. The obtained results illustrated a decrement in the gases' permeation in the presence of SiO2 particles. By increasing the filler content up to 15 wt% and pressure of 8 bar, the gas permeation value of the CO2, O2, and N2 decreased 36%, 54%, and 59%, respectively. However, the permselectivity of the CO2/N2 and O2/N2 increased considerably, 55% and 13% respectively. On the contrary, by raising the temperature, a dramatic augmentation in the permeability of all gases with a simultaneous reduction in the selectivity values of both gas pairs was revealed. Increasing the pressure led to a decrease in the permeability values of all membranes for O2 and N2, whereas the permeability for CO2 increased with the pressure. Nevertheless, the selectivity values for the pair of gases increased (at a pressure of 10 bar, 1.66 and 1.17 times the neat PU for CO2/N2 and O2/N2, respectively). Furthermore, the permeability of the CO2, O2, and N2 for the mixed gases was smaller than for pure ones at the same gas upstream pressure. Nonetheless, like the pure gas, the selectivity of both pair gases increased. 相似文献
5.
6.
The electrochemical trimerization of 4-tert-butylcatechol via anodic oxidation of 4-tert-butylcatechol (1) is described. The mechanism of trimerization has been studied in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The electrochemical synthesis of trimer 3a has been successfully performed in an undivided cell in good yield and purity. 相似文献
7.
Mehdi Javidi M. R. Nematollahi M. M. Lalehparvar A. Ghassemi 《Journal of Failure Analysis and Prevention》2016,16(2):209-215
The objective of this work was to analyze a reported pitting damage mechanism in water piping of a power plant. The investigated material was a longitudinal-seam welded pipe which was made of AISI 321 austenitic stainless steel. Pitting occurred on the internal surfaces of the pipe and adjacent to the girth welds. Optical emission spectrometry, metallography, and electrochemical testing were the techniques employed to analyze the failure. The investigation showed that the flowing water contained chloride ions in which AISI 321 austenitic stainless steel is not immune against pitting corrosion. In addition, the polarization data showed the susceptibility of the material to pitting corrosion in the service conditions. Furthermore, the result of double loop electrochemical potentiokinetic reactivation tests showed that the material was sensitized during welding. It was found that the damage was due to pitting corrosion in chloride-containing water. Thus, it was recommended to replace the pipe with material having higher pitting resistance equivalent number to be more resistant against pitting corrosion. 相似文献
8.
From the birth of multi-spectral imaging techniques, there has been a tendency to consider and process this new type of data as a set of parallel gray-scale images, instead of an ensemble of an n-D realization. However, it has been proved that using vector-based tools leads to a more appropriate understanding of color images and thus more efficient algorithms for processing them. Such tools are able to take into consideration the high correlation of the color components and thus to successfully carry out energy compaction. In this paper, a novel method is proposed to utilize the principal component analysis in the neighborhoods of an image in order to extract the corresponding eigenimages. These eigenimages exhibit high levels of energy compaction and thus are appropriate for such operations as compression and watermarking. Subsequently, two such methods are proposed in this paper and their comparison with available approaches is presented. 相似文献
9.
10.
In this study, a series of castor oil based polyurethane/organically modified montmorillonite (OMMT) clay nanocomposite coatings have been successfully prepared by effective dispersing of OMMT nano-layers in polyurethane matrix through an ultrasonication assisted process. Effectiveness of ultrasonication process in de-agglomeration of clay stacks in castor oil dispersions was evaluated by optical microscopy and sedimentation test. Structure of nanocomposite coatings was investigated by wide angle X-ray diffraction (WAXD) and Fourier-transform infrared spectroscopy (FT-IR). The anticorrosive properties of nanocomposite coatings were characterized by electrochemical impedance spectroscopy (EIS), Tafel polarization study, water absorption and pull-off adhesion tests. The experimental results showed that PU/OMMT nanocomposite coatings were superior to the neat PU in corrosion protection effects. Also, it was observed that the corrosion protection of polyurethane organoclay nanocomposite coatings is improved as the clay loading is increased up to 3 wt.%. 相似文献