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101.
The complex networks approach for authorship attribution of books   总被引:1,自引:0,他引:1  
Authorship analysis by means of textual features is an important task in linguistic studies. We employ complex networks theory to tackle this disputed problem. In this work, we focus on some measurable quantities of word co-occurrence network of each book for authorship characterization. Based on the network features, attribution probability is defined for authorship identification. Furthermore, two scaling exponents, q-parameter and α-exponent, are combined to classify personal writing style with acceptable high resolution power. The q-parameter, generally known as the nonextensivity measure, is calculated for degree distribution and the α-exponent comes from a power law relationship between number of links and number of nodes in the co-occurrence network constructed for different books written by each author. The applicability of the presented method is evaluated in an experiment with thirty six books of five Persian litterateurs. Our results show high accuracy rate in authorship attribution.  相似文献   
102.
α-Fe2O3 nanodiscs and Mn3O4 nanoparticles have been prepared by the 1,10-phenanthroline as complexing agent in the presence of sodium hydroxide under hydrothermal conditions. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectra. The average diameter of α-Fe2O3 nanodiscs is of 2 μm. In the case of Mn3O4 sample, the Mn3O4 crystallites are nanoparticles with an average size of 34 nm. A formation mechanism for the α-Fe2O3 and Mn3O4 nanomaterials was proposed.  相似文献   
103.
On the basis of fundamental parameter approaches, the validity of standardless wavelength dispersive X‐ray fluorescence (WDXRF) and X‐ray powder diffraction algorithms was confirmed for analyzing Egyptian iron ore samples collected from two different locations, Aswan and Baharyia. The studied Egyptian iron ores represent different depositional environments and consequently exhibit variable mineralogical and chemical compositions. In the case of WDXRF analysis, the ground powders of iron ore samples were mixed and pressed with low contamination binder in a mass ratio of wax: sample = 4: 0.9 g at 120 kN cm?2. A standardless method for quantitative WDXRF was employed, which requires accurate determination of the amount of organic material in the sample. On the basis of differential thermal analysis, a new method is introduced for the determination of loss of ignition. With the application of the proposed method and standardless quantitative analysis, results for 12 elements in iron ores were obtained: Fe, Mn, Mg, Si, Al, Ca, Na, K, S, Ba, Zn, and Cl. The reliability and precision of the adopted procedure were tested against a standard reference material ‘Iron ore concentrate (SRM 690, NIST, USA)’. The quantitative analysis results of the certified reference material were found acceptable. Depending on the WDXRF results, the powder samples were directly introduced to X‐ray powder diffraction goniometry, and the phase compositions were quantitatively determined by using a standardless analysis program based on Rietveld method. The main phases of all iron ore samples are the hematite and goethite, whereas other phases are found with varying ratios, namely quartz, nordstrandite, rhodochrosite, kaolinite, todorokit, bassanit, andydrite, and hydroxyapatite. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
104.
Triamide derivatives have been synthesized in good yields in a novel, one-pot, five-component, and efficient process by the reaction of Z-oxazolone, water, primary amines, aldehydes, isocyanides, in the presence of catalytic amount of KAl(SO4)2·12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available reagent via Ugi reaction in aqueous solution.  相似文献   
105.
Density functional theory (DFT) calculations were performed to investigate stabilities and properties for uracil (U)-functionalized carbon nanotubes (CNTs). To this aim, the optimized molecular properties were evaluated for (n, 0) models of CNTs (n = 3–16) in the original and U-functionalized forms. The results indicated that the dipole moments and energy gaps were independent of tubular diameters whereas the binding energies showed that the U-functionalization could be better achieved for n = 8–11 curvatures of (n, 0) CNTs. Further studies based on the evaluated atomic-scale properties, including quadrupole coupling constants (C Q ), indicated that the electronic properties of atoms could detect the effects of diameters variations of (n, 0) CNTs, in which the effects were very much significant for the atoms around the U-functionalization regions. Finally, the achieved results of singular U, original CNTs, and CNT-U hybrids were compared to each other to demonstrate the stabilities and properties for the U-functionalized (n, 0) CNTs.  相似文献   
106.
Here, for the first time, the real‐time and broadband manipulation of terahertz (THz) waves are acquired by introducing a multifunctional graphene‐based coding metasurface (GBCM). The designed structure consists of subwavelength patterned graphene units whose operational statuses can be dynamically switched between two digital states of “0” and “1”. By engineering the spatial distribution of chemical potentials across the GBCM, various scattering patterns having single, two, four, and numerous reflection beams are elaborately achieved just within one planar structure. To compute the far‐field pattern of GBCM, an inverse discrete Fourier transform (IDFT) is established, providing a fast and efficient design method. The proposed GBCM provides a low reflection bellow ?10 dB over a broad frequency band ranging from 1 THz to 1.9 THz. In addition, the metasurface retains its low reflection behavior in a wide range of incident wave angles for both TE and TM polarizations. According to conformal invariance of graphene sheets, the stealth property of GBCM is well preserved while wrapping around a curved object. The proposed technique of real‐time scattering manipulation leads to multifunctional THz devices, opening new routes contributing to numerous applications such as imaging and stealth technology.  相似文献   
107.
We study the entanglement of dressed atom and its spontaneous emission in a three-level Λ-type closed-loop atomic system in a multi-photon resonance condition and beyond it.It is shown that the von Neumann entropy in such a system is phase-dependent,and it can be controlled by either the intensity or relative phase of applied fields.It is demonstrated that for the special case of the Rabi frequency of applied fields,the system is disentangled.In addition,we take into account the effect of Doppler broadening on the entanglement and it is found that a suitable choice of laser propagation direction allows us to obtain the steady state degree of entanglement(DEM) even in the presence of the Doppler effect.  相似文献   
108.
Thin films of SnSb2S4 have been prepared on glass substrate by using thermal evaporation techniques. The films were annealed in argon gas at low pressure in sealed glass ampoules at 85 °C, 150 °C, 275 °C and 325 °C. XRD of the films reveal that the low temperature annealed films are poly crystalline while the as deposited films and high annealed films are in amorphous states. There is no adequate variation in the photoconductivity response of the amorphous and crystalline phases. The transmittance of the films is low and having no transmittance below 740 nm. The band gap calculated by ellipsometry technique is in the range of 1.82–3.1 eV. The films have n-type conductivity but the film annealed at 325 °C show p-type conductivity.  相似文献   
109.
In this paper, we present an image processing algorithm to automatically and more precisely detect the boundary between the main skin layers: stratum corneum, epidermis, and dermis. The aim of the proposed skin layer detection algorithm is to assist the dermatologists to measure the epidermal thickness (ET) for skin diseases diagnosis and also to assist pharmacologists so that they can make a better decision for prescribing according to the advancement of the skin disorders characterized with ET change.  相似文献   
110.
The natural broadening of hydrogen atom spectrum based on the minimal length uncertainty is calculated. We will show that the natural broadening of hydrogen atom spectrum receives any correction.  相似文献   
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