Vietnam Academy of Science and Technology: Journals Online
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SOME NEW RESULTS ON AUTOMATIC IDENTIFICATION OF VIETNAMESE FOLK SONGS CHEO AND QUANHO
No full text Vietnamese folk songs are very rich in genre and content. Identifying Vietnamese folk tunes will contribute to the storage and search for information about these tunes automatically. The paper will present an overview of the classification of music genres that have been performed in Vietnam and abroad. For two types of very popular folk songs of Vietnam such as Cheo and Quan ho, the paper describes the dataset and GMM (Gaussian Mixture Model) to perform the experiments on identifying some of these folk songs. The GMM used for experiment with 4 sets of parameters containing MFCC (Mel Frequency Cepstral Coefficients), energy, first derivative and second derivative of MFCC and energy, tempo, intensity, and fundamental frequency. The results showed that the parameters added to the MFCCs contributed significantly to the improvement of the identification accuracy with the appropriate values of Gaussian component number M. Our experiments also showed that, on average, the length of the excerpts was only 29.63% of the whole song for Cheo and 38.1% of the whole song for Quan ho, the identification rate was only 3.1% and 2.33% less than the whole song for Cheo and Quan ho respectively
GIS based frequency ratio method for landslide susceptibility mapping at Da Lat City, Lam Dong province, Vietnam
No full textLandslide susceptibility mapping of the city of Da Lat, which is located in the landslide prone area of Lam Dong province of Central Vietnam region, was carried out using GIS based frequency ratio (FR) method. There are number of methods available but FR method is simple and widely used method for landslide susceptibility mapping. In the present study, eight topographical and geo-environmental landslide-conditioning factors were used including slope, elevation, land use, weathering crust, soil, lithology, distance to geology features, and stream density in conjunction with 70 past landslide locations. The results show that 6.27% of the area is in the very low susceptibility area, 21.03% in the low susceptibility area, 27.09% in the moderate susceptibility area and 27.41% of the area is in the high susceptibility zone and 18.21% in the very high susceptibility zone. The landslide susceptibility map produced in this study helps to assist decision makers in proper land use management and planning
Polarization Observables in WZ Production at the 13 TeV LHC: Inclusive Case
Get PDFWe present a study of the polarization observables of the and bosons in the process at the 13 TeV Large Hadron Collider. The calculation is performed at next-to-leading order, including the full QCD corrections as well as the electroweak corrections, the latter being calculated in the double-pole approximation. The results are presented in the helicity coordinate system adopted by ATLAS and for different inclusive cuts on the di-muon invariant mass. We define left-right charge asymmetries related to the polarization fractions between the and channels and we find that these asymmetries are large and sensitive to higher-order effects. Similar findings are also presented for charge asymmetries related to a P-even angular coefficient
Genetic characteristics of Panax vietnamensis Ha & Grushv. populations based on ssr
Get PDFThe results of genetic analysis of two Panax vietnamensis populations, collected in Tac-ngo ginseng garden, Tra Linh commune, Quang Nam Province and Mang ri ginseng garden, Kon Tum Province, showed that the population of ngoc linh ginseng in Quang Nam has higher alen frequency compared to the Ngoc Linh ginseng population in Kon Tum (AR = 2.27 AR = 2.05). The population of ngoc linh ginseng in Quang Nam has the expected heterozygous frequency (He) higher than the expected heterozygous frequency of the ginseng population in Kon Tum (0.42 0.4). The observed heterozygous frequency (Ho) of the ngoc linh population in Quang Nam was also higher than the observed heterozygous frequency compared to the ngoc linh ginseng population in Kon Tum (0.49 0.43). These results demonstrated that both populations of ngoc linh ginseng in Quang Nam and Kon Tum are maintaining high heterozygous frequencies; self-pollination has not affected to the genetic structure of these both populations yet. However, the population of ngoc linh ginseng in Quang Nam showed a higher level of diversity and heterozygous frequency than the ngoc linh ginseng population in Kon Tum.
CHARACTERIZATION OF A SYMMETRIC FISHNET METAMATERIAL IN THE M-BAND
No full textWe study a symmetric fishnet metamaterial working in the M-band (60 - 100 GHz). Significant effects of the dielectric spacer and the metal pattern on the electromagnetic response were investigated. It was found that the left-handed peak was shifted, enhanced or even destroyed by changing the thickness and the permittivity of dielectric spacer. In addition, we also present the effect of metal pattern properties on the left-handed transmission spectra. The effective medium parameters are calculated using the standard retrieval method
BUCKLING ANALYSIS OF THE INDUSTRIAL FACTORY MODEL BY FINITE ELEMENT METHOD
Get PDFBuckling is a subject that has been discussed for a long time, however, it still be studied and developed due to its practicality. The following article introduces two methods that are used to solve the problems involving buckling of the beam, shell and solid with an I shape cross-section having different cases of boundary load. The theory which is used in this article is Euler's formula and Eurocode 3 standard. The analytical results by ANSYS commercial software are compared with the theoretical results and results from Eurocode 3 standard. The authors based on the reliability of the calculating results to simulate buckling of the industrial factory model with different cases of load conditions. The simulating results show a general view of buckling cases
SYNTHESIS OF OCTAHEDRON Zn2SnO4 BY HYDROTHERMAL METHOD FOR HIGH PERFORMANCE ETHANOL SENSOR
No full textThe octahedron Zn2SnO4 was prepared through a facile hydrothermal method for ethanol gas-sensing application. The synthesized material was characterized by scanning electron microscopy (SEM), powder x-ray diffraction (XRD). The gas-sensing characteristics were measured at various concentrations of ethanol at temperature ranging from 350 to 450 ºC. The gas response exhibits good linear relationship with the increasing of ethanol concentrations in the range of 50-250 ppm. Gas-sensing measurements demonstrated that the synthesized octahedron Zn2SnO4 showed n-type semiconducting behavior, where the sensor resistance decreased upon exposure to ethanol. Results pointed out that the sensors showed the highest response value at operating temperature of 400 ºC. The sensor response value was 30 at 250 ppm ethanol. Such outstanding gas sensing property might be attributed to the morphology of the octahedra which provided large contact area between Zn2SnO4 and target gas. The synthesized octahedron Zn2SnO4 is potential for detecting traces of ethanol
VIBRATION OF FGSW BEAMS UNDER NONUNIFORM MOTION OF MOVING LOAD USING AN EFFICIENT THIRD-ORDER SHEAR DEFORMATION FINITE ELEMENT FORMULATION
Get PDFVibration of functionally graded sandwich (FGSW) beams under nonuniform motion of a moving load is studied using a third-order shear deformation finite element formulation. The beams consists three layers, a homogeneous ceramic core and two functionally graded faces. Instead of the rotation, the finite element formulation is derived by using the transverse shear rotation as a unknown. Newmark method is used to compute the dynamic response of the beams. Numerical result reveals that the derived formulation is efficient, and it is capable to give accurate vibration characteristics by a small number of the elements. A parametric study is carried out to illustrate the effects of the material distribution, layer thickness ratio and moving load speed on the dynamic behavior of the beams. The influence of acceleration and deceleration of the moving load on the vibration of the beams is also examined and discussed
Shallow landslide susceptibility mapping: A comparison between classification and regression tree and reduced error pruning tree algorithms
No full textShallow landslides through land degrading not only lead to threat the properly and life of human but they also may produce huge ecosystem damages. The aim of this study was to compare the performance of two decision tree machine learning algorithms including classification and regression tree (CART) and reduced error pruning tree (REPTree) for shallow landslide susceptibility mapping in Bijar, Kurdistan province, Iran. We first used 20 conditioning factors and then they were tested by information gain ratio (IGR) technique to select the most important ones. We then constructed a geodatabase based on the selected factors along with a total of 111 landslide locations with a ratio of 80/20 (for calibration/validation). The performance of the models was checked by the true positive rate (TP Rate), false positive rate (FP Rate), precision, recall, F1-Measure, Kappa, mean absolute error, and area under the receiver operatic curve (AUC). Results of IGR specified that the slope angle and TWI had the most contribution to shallow landslide occurrence in the study area. Moreover, results concluded that although these models had a high goodness-of-fit and prediction accuracy, the CART model (AUC=0.856) outperformed the REPTree model (AUC=0.837). Therefore, the CART model can be used as a promising tool and also as a base classifier to hybrid with optimization algorithms and Meta classifiers for spatial prediction of shallow landslide-prone areas
All-dielectric Metamaterial for Electromagnetically-induced Transparency in Optical Region
Get PDFMetamaterial (MM) is emerging as a promising approach to manipulate electromagnetic waves, spanning from radio frequency to the optical region. In this paper, we employ an effect called electromagnetically-induced transparency (EIT) in all-dielectric MM structures to create a narrow transparent window in opaque broadband of the optical region (580-670 nm). Using dielectric materials instead of metals can mitigate the large non-radiative ohmic loss on the metal surface. The unit-cell of MM consists of Silicon (Si) bars on Silicon dioxide (SiO) substrate, in which two bars are directed horizontally and one bar is directed vertically. By changing the relative position and dimension of the Si bars, the EIT effect could be achieved. The optical properties of the proposed MM are investigated numerically using the finite difference method with commercial software Computer Simulation Technology (CST). Then, characteristic parameters of MM exhibiting EIT effect (EIT-MM), including Q-factor, group delay, are calculated to evaluate the applicability of EIT-MM to sensing and light confinement