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881.
Shao J Porikli F Chellappa R 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(8):2109-2121
We present an algorithm for nonrigid contour tracking in heavily cluttered background scenes. Based on the properties of nonrigid contour movements, a sequential framework for estimating contour motion and deformation is proposed. We solve the nonrigid contour tracking problem by decomposing it into three subproblems: motion estimation, deformation estimation, and shape regulation. First, we employ a particle filter to estimate the global motion parameters of the affine transform between successive frames. Then we generate a probabilistic deformation map to deform the contour. To improve robustness, multiple cues are used for deformation probability estimation. Finally, we use a shape prior model to constrain the deformed contour. This enables us to retrieve the occluded parts of the contours and accurately track them while allowing shape changes specific to the given object types. Our experiments show that the proposed algorithm significantly improves the tracker performance. 相似文献
882.
This article describes an emulation-based method for locating stuck-at faults in combinational and synchronous sequential
circuits. The method is based on automatically designing a circuit which implements a closest-match fault location algorithm
specialized for the circuit under diagnosis (CUD). This method allows designers to perform dynamic fault location of stuck-at
faults in large circuits, and eliminates the need for large storage required by a software-based fault dictionary. In fact,
the approach is a pure hardware solution to fault diagnosis. We demonstrate the feasibility of the method in terms of hardware
resources and diagnosis time by experimenting with ISCAS85 and ISCAS89 circuits. The emulation-based diagnosis method speeds
up the diagnosis process by an order of magnitude compared to the software-based fault diagnosis. This speed-up is important,
especially, when the on-line diagnosis of safety–critical systems is of concern.
相似文献
Daniel G. SaabEmail: |
883.
Duran M Unal A Inanc MT Kocyigit I Oguz F Ocak A Ozdogru İ Kasapkara A Karakaya E Oymak O 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(3):334-340
We aimed to evaluate the long-term effect of hemodialysis (HD) treatment on left and right ventricular (LV and RV) functions in patients with end-stage renal disease. The study population consisted of 22 patients with newly diagnosed end-stage renal disease. Before an arteriovenous fistula was surgically created for HD, the patients were evaluated by echocardiography for systolic and diastolic functions. After the first HD session (mean 24.22 ± 2.14 months), the second echocardiographic evaluations were performed. Left ventricular and RV functions before and after long-term HD treatment were compared. The mean age was 55 ± 13 years and 10 (45%) of the patients were female. After long-term HD treatment, the isovolumic relaxation time was significantly decreased; however, the peak early (E) and late (A) diastolic mitral inflow velocities, E/A ratio, and deceleration time of E wave were not significantly different from the baseline measurements. Also, there was no significantly change in the early diastolic velocity (Ea) of the lateral mitral anulus and the E/Ea ratio. Pulmonary vein peak diastolic velocity, peak atrial reversal velocity, and peak atrial reversal velocity duration remained almost unchanged even though the pulmonary vein peak systolic velocity and the pulmonary vein peak systolic velocity/pulmonary vein peak diastolic velocity ratio were significantly lower after long-term HD treatment. In addition, LV systolic functions, LV diameters, LV mass index, left atrium size, and RV diastolic functions were not statistically different after long-term HD treatment. The myocardium is exposed to hemodynamic, metabolic, and neuro-humoral abnormalities during HD treatment; however, the long-term effects of HD on ventricular functions are not clearly known. The present study showed that the long-term effects of HD on LV and RV functions were insignificant in patients with end-stage renal disease. We have demonstrated that the LV and RV functions did not change significantly after long-term HD treatment. We suggest that this result may be due to regulated blood pressure levels of the patients, treatment of anemia and other metabolic disorders during the HD period and the prevention of weight gain and hypervolemia. 相似文献
884.
885.
Oligo{2,2′‐{1,4‐phenylenebis[nitrilomethylylidene]}bis(6‐methoxyphenol)} (OPNMMP) was synthesized from o‐vanillin and p‐phenylene diamine by oxidative polycondensation with NaOCl in an aqueous alkaline. Then, a new Schiff Base epoxy oligomer resin, OPNMMP–epichlorohydrine (EPC), was produced with EPC. The structures of the resulting compounds were confirmed by Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, 1H‐NMR, and 13C‐NMR. Further characterization processes were preformed by thermogravimetry (TG)–differential thermal analysis, gel permeation chromatography, and solubility testing. Also, the kinetics of the thermal decomposition of OPNMMP–EPC were investigated by thermogravimetric analysis. The TG curves showed that the thermal decomposition of OPNMMP–EPC occurred in one stage. The kinetic parameters related to the decomposition kinetics of OPNMMP–EPC were obtained from TG curves with the following methods: Friedman, Flynn–Wall–Ozawa, Kissinger, invariant kinetic parameter, and Coats–Redfern (CR), under an N2 dynamic atmosphere and different heating rates (5, 10, 15, and 20°C/min). The mechanism function and pre‐exponential factor were also determined by a master plots method. The apparent activation energies of the thermal decomposition were calculated from these methods for OPNMMP–EPC. The analysis of the results obtained by the CR and master plots methods showed that the decomposition mechanism of OPNMMP–EPC in N2 was a deceleration‐type mechanism. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
886.
Fatih Semerci Okan Zafer Ye?ilel Ertan ?ahin Yusuf Yerli Ramazan Topkaya 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(2):261-268
A novel 2D coordination polymer, {[Cu(en)2][Cu(μ3-pydc)2]·6H2O}
n
(1) pyridine-2,3-dicarboxylic acid (pydcH2); ethylenediamine (en), based on the metalloligand [Cu(μ-pydcH)2]
n
, has been prepared and characterized by IR, UV–Vis and ESR spectroscopy, thermal analysis, differential scanning calorimetry
and single crystal X-ray diffraction techniques. The temperature dependent magnetic properties have also been studied. The
pydc ligand exhibits tetradentate-μ3 bridging mode, being coordinated through three carboxylate oxygens and one nitrogen atom. The complex contains two copper(II)
ions that exhibit two different coordination environment with two en and two pydc ligands. The single crystal structure shows
that the complex forms a 3D framework with 2D layers along the c-axis. Van der Waals interactions are responsible for the self-assembly of the layer into a 3D network. 相似文献
887.
Sugunan A Zhao Y Mitra S Dong L Li S Popov S Marcinkevicius S Toprak MS Muhammed M 《Nanotechnology》2011,22(42):425202
Synthesis of colloidal nanocrystals of II-VI semiconductor materials has been refined in recent decades and their size dependent optoelectronic properties have been well established. Here we report a facile synthesis of CdSe-CdS core-shell heterostructures using a two-step hot injection process. Red-shifts in absorption and photoluminescence spectra show that the obtained quantum dots have quasi-type-II alignment of energy levels. The obtained nanocrystals have a heterostructure with a large and highly faceted tetrahedral CdS shell grown epitaxially over a spherical CdSe core. The obtained morphology as well as high resolution electron microscopy confirms that the tetrahedral shell have a zinc blende crystal structure. A phenomenological mechanism for the growth and morphology of the nanocrystals is discussed. 相似文献
888.
Fatih Bulut Özgür Ozturk Selim Acar Gürcan Yildirim 《Microscopy research and technique》2022,85(4):1502-1517
In the present study, the one-dimensional ZnO nanorod structures are produced within the different nickel and aluminum molecular weight ratios of 0–7% using the hydrothermal method. It is found that the aluminum (Al) and nickel (Ni) impurities with different ionic radius, chemical valence, and electron configurations of outer shell cause to vary the fundamental characteristic features including the crystallinity quality, crystallite size, surface morphology, nanorod diameter, optical absorbance, energy band gap, resistance, gas response, and gas sensing properties. The structural analyses performed by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicate that the samples are found to crystallize in the hexagonal wurtzite structure. The presence of optimum nickel and aluminum in the crystal system improves considerably the crystallinity quality and surface morphology. Additionally, the combination of electron dispersive X-ray (EDX) and XRD results declare that the Ni and Al impurities incorporate successfully into the ZnO crystal structure. Moreover, the diameters of nanorod structures in 1D orientation are determined to be 80 nm or below. The hexagonal wurtzite-type ZnO nanorod structure prepared by 5% Ni has more space between the nanorods and thus presents higher response to the CO2 detection. Further, the optical absorbance spectra display that the band gap value is observed to decrease regularly with the increment in the doping level as a result of band shrinkage effect depending on the enhancement of mobile hole carrier concentrations in the crystal structure. In other words, the doping mechanism leads to vary the homogeneities in the interfacial charges, nanorod diameters, ZnO oxide layer composition and thickness. The last test conducted in this study is responsible for the determination of CO2 gas sensing levels. The obtained gas sensing results are further compared with each other and literature findings. It is observed that 5% Ni-doped sample provides more successful results than other samples in the sensing CO2 gas at the different concentrations. All in all, the paper establishing a strong methodology between doping mechanism and change in the fundamental characteristic features of hexagonal wurtzite-type ZnO with the aid of advanced microscopy techniques will become pioneering research to answer key questions in materials sciences and electronic research. 相似文献
889.
Nikheel Bhojraj Rathod M. Sc Rahul Chudaman Ranveer PhD Prashant Kishor Bhagwat PhD Fatih Ozogul PhD Sottawat Benjakul PhD Santhosh Pillai PhD Uday Shriramrao Annapure PhD 《Comprehensive Reviews in Food Science and Food Safety》2021,20(5):4407-4425
Cold plasma (CP) is an upcoming technology implemented for the preservation of highly perishable foods, especially aquatic food products (AFPs). The high moisture content, high-quality protein with all essential amino acids and unsaturated fatty acids makes AFP more susceptible to microbial spoilage and oxidation of lipids and proteins. Spoilage lowers the nutritive value and could generate toxic components, making it unsafe for consumption. In recent times, the rising demand for food products of aquatic origin with preserved quality and extended shelf-life has been recorded. In addition, minimally or nonthermally processed and preserved foods are gaining great attention. CP technology has demonstrated an excellent ability to inactivate microorganisms without promoting their resistance and triggering some deteriorative enzymes, which are typical factors responsible for the spoilage of AFP. Consequently, CP could be recommended as a minimal processing intervention for preserving the quality of AFP. This review focuses on different mechanisms of fish spoilage, that is, by microorganisms and oxidation, their inhibition via the application of CP, and the retention of quality and shelf-life extension of AFP. 相似文献
890.
Fatih Ungan Unal Yesilgul Serpil ?akiro?lu Esin Kasapoglu Ayse Erol Mehmet Cetin Arikan Huseyin Sar? Ismail S?kmen 《Nanoscale research letters》2012,7(1):606
Within the envelope function approach and the effective-mass approximation, we have investigated theoretically the effect of an intense, high-frequency laser field on the bound states in a GaxIn1 − xNyAs1 − y/GaAs double quantum well for different nitrogen and indium mole concentrations. The laser-dressed potential, bound states, and squared wave functions related to these bound states in Ga1 − xInxNyAs1 − y/GaAs double quantum well are investigated as a function of the position and laser-dressing parameter. Our numerical results show that both intense laser field and nitrogen (indium) incorporation into the GaInNAs have strong influences on carrier localization. 相似文献