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31.
32.
We present in this letter a blind frame synchronization method based on a Maximum A Posteriori probability (MAP) approach. Applied to coded communication systems, this method is based on the calculation of the Log-likelihood Ratios (LLR) of the syndrome obtained according to the parity check matrix of the code. After presenting the proposed method, we compare it to an existing blind synchronization method previously introduced. Simulation results show that the proposed method outperforms the existing one and presents good performance when applied to codes having a sparse parity check matrix such as Low Density Parity Check (LDPC) codes and convolutional codes. 相似文献
33.
Imad Hussain S.N. Khan Eun Ji Kim So Eun Jeon Bon Heun Koo 《Ceramics International》2018,44(3):2892-2899
A systematic study focusing on the effect of Niobium (Nb) doping on the structural, magnetic and magnetocaloric properties of Ba2FeMoO6 samples is presented here. The samples of interest Ba2FeMo1?xNbxO6 (0 ≤ x ≤ 0.4) were prepared using the solid state reaction method and were confirmed to possess a cubic structure with Fm-3m space group using the X-ray diffraction analysis and Rietveld refinement. A second order of ferromagnetic phase transition was recorded in both the pure as well as the Nb doped samples using the temperature dependent magnetization and Arrott plots analysis. The pristine Ba2FeMoO6 (BFMO) sample indicated a spontaneous magnetization (34.6 emu/g at 100 K) with a relatively sharp magnetic transition at the Curie temperature (TC) of 315 K as compared to the doped samples. A magnetic entropy change of 0.93 Jkg?1K?1 at an applied magnetic field of 2.5 T was measured for the pure BFMO sample. The doped BFMO samples with Mo partially substituted by Nb however, were observed to effectively modify the TC accompanied by a decrease in magnetization. The results investigated in this work suggest that the magnetic and magnetocaloric properties of the BFMO can be tailored by controlled Nb doping which is of significant importance in order to realize the numerous potential applications of the material in the magnetic refrigeration technology. 相似文献
34.
Wan-Mohtar Wan Abd Al Qadr Imad Ab Kadir Safuan Halim-Lim Sarina Abdul Ilham Zul Hajar-Azhari Siti Saari Nazamid 《Food science and biotechnology》2019,28(6):1747-1757
Food Science and Biotechnology - In submerged-liquid fermentation, seven key parameters were assessed using one-factor-at-a-time to obtain the highest GABA yield using an industrial soy sauce koji... 相似文献
35.
Maadeed Somaya Al Jiang Xudong Rida Imad Bouridane Ahmed 《Multimedia Tools and Applications》2019,78(5):5665-5679
Multimedia Tools and Applications - Among various palmprint identification methods proposed in the literature, Sparse Representation for Classification (SRC) is very attractive, offering high... 相似文献
36.
Burnishing is a profitable process of surface finishing due to its ability to be automated, which makes burnishing method more desirable than other finishing methods. To obtain high surface finish, non-stop operation is required for CNC machine and we can attain that by choosing a suitable trajectory of the finishing tool. In other words, burnishing paths should be multidirectional rather than monotonic, in order to cover uniformly the surface. Indeed, the burnishing force is also a key parameter of the burnishing process because it determines the degree of plastic deformation, and that makes determining the optimum burnishing force an essential step of the burnishing process a success. Therefore, we consider the strategy of ball burnishing path and the burnishing force as variable parameters in this study. In this paper, we propose a new strategy of burnishing tool path with trochoid cycles that achieves a multidirectional burnishing of the surface according to various patterns. Taking into consideration the optimum burnishing force, to improve flat surface finish of AL6061-O samples by reducing the surface roughness parameter (Rz). Experiments carried out on 3-axis milling machine show that the proposed trochoidal path is more effective than the conventional one. 相似文献
37.
Mostafa El Mallahi Amal Zouhri Abderrahim Mesbah Aissam Berrahou Imad El Affar Hassan Qjidaa 《Multimedia Tools and Applications》2018,77(6):6583-6604
In this paper, we introduce new sets of 2D and 3D rotation, scaling and translation invariants based on orthogonal radial Racah moments. We also provide theoretical mathematics to derive them. Thus, this work proposes in the first case a new 2D radial Racah moments based on polar representation of an object by one-dimensional orthogonal discrete Racah polynomials on non-uniform lattice, and a circular function. In the second case, we present new 3D radial Racah moments using a spherical representation of volumetric image by one-dimensional orthogonal discrete Racah polynomials and a spherical function. Further 2D and 3D invariants are extracted from the proposed 2D and 3D radial Racah moments respectively will appear in the third case. To validate the proposed approach, we have resolved three problems. The 2D/ 3D image reconstruction, the invariance of 2D/3D rotation, scaling and translation, and the pattern recognition. The result of experiments show that the Racah moments have done better than the Krawtchouk moments, with and without noise. Simultaneously, the mentioned reconstruction converges rapidly to the original image using 2D and 3D radial Racah moments, and the test 2D/3D images are clearly recognized from a set of images that are available in COIL-20 database for 2D image, and PSB database for 3D image. 相似文献
38.
In this paper, we extend a temporal defeasible logic with a modal operator Committed to formalize commitments that agents undertake as a consequence of communicative actions (speech acts) during dialogues. We represent commitments as modal sentences. The defeasible dual of the modal operator Committed is a modal operator called Exempted. The logical setting makes the social-commitment based semantics of speech acts verifiable and practical; it is possible to detect if, and when, a commitment is violated and/or complied with. One of the main advantages of the proposed system is that it allows for capturing the nonmonotonic behavior of the commitments induced by the relevant speech acts. 相似文献
39.
Ali A. Badran Ihmad A. Al-Hallaq Imad A. Eyal Salman Mohammad Z. Odat 《Desalination》2005,172(3):227-234
A single-stage, basin-type solar still and a conventional flat-plate collector were connected together in order to studythe effect of augmentation on the still under local conditions. The still inlet was connected to a locally made, fin-tube collector such that its outlet was fed to the still basin instead of the common storage tank. Measurements of various temperatures, solar intensities and distilled water productions were taken for several days at various operating conditions. Several modes of operation were studied: still connected to collector for a 24-h period; still connected only during sunlight hours from 8 am to 5 pm, and still operating alone for a 24-h period. These tests were performed using tap water and saline water as a feed. It was found that the mass of distilled water production using augmentation was increased by 231% in the case of tap water as a feed and by 52% in the case of salt water as a feed. 相似文献
40.
Abuznaid M Sallam AS Hamdan I Al-Hussaini M Bani-Jaber A 《Drug development and industrial pharmacy》2008,34(4):434-444
Diclofenac-bismuth complexation was attempted by mixing diclofenac sodium (Na) and bismuth-subcitrate aqueous solutions at diclofenac:bismuth molar ratio of 3:1. A solid precipitate was obtained and isolated. The precipitate was characterized for stoichiometric ratio of diclofenac-bismuth complexation using capillary electrophoresis, which showed 1:1 complexation. In addition, nuclear magnetic resonance and Fourier transform infrared analysis were performed for the isolated solid complex and indicated that bismuth was in coordinate bond formation with the carboxylate group of diclofenac. In comparison with diclofenac Na powder, the complex was evaluated as an aqueous suspension for in vitro drug dissolution. The complex exhibited a faster dissolution rate than and similar dissolution extent as diclofenac Na. In comparison with an aqueous solution of diclofenac Na and an aqueous suspension of physical mixture of diclofenac acid (suspended) and bismuth-subcitrate (dissolved), the aqueous complex suspension was evaluated for ulcerogenic effect in rats upon oral administration. The complex led to more gastric ulceration than diclofenac Na, which was not in accordance with the antiulcer properties of bismuth. This antiulcer effect was shown as the physical mixture administration was accompanied with lower gastric ulceration than diclofenac Na administration. These gastric ulceration results were explained in terms of the difference in particle size between solid diclofenac acid formed as a result of the complex breakdown in an acidic medium (0.1 M HCl to simulate the gastric fluid) and that formed as a result of diclofenac Na neutralization. Diclofenac acid particles formed from the complex breakdown were of average size, three times smaller of those formed as a result of diclofenac Na protonation. This difference in particle size was correlated with the higher gastric ulceration associated with the complex than with diclofenac Na in terms of higher coverage of the gastric mucosa with diclofenac, and consequently, higher local ulceration. 相似文献