Singing voice detection or vocal is a classification task that determines whether given audio segment contains singing voices. This plays very important role in vocal-related music information retrieval tasks, such as singer identification. Although humans can easily distinguish between and nonsinging parts, it still difficult for machines to do so. Most existing methods focus on feature engineering with classifiers, which rely the experience of algorithm designer. In recent years, deep...

Vocal melody extraction is an important and challenging task in music information retrieval. One main difficulty that, most of the time, various instruments singing voices are mixed according to harmonic structure, making it hard identify fundamental frequency (F0) a voice. Therefore, reducing interference accompaniment beneficial pitch estimation In this paper, we first adopted high-resolution network (HRNet) separate vocals from polyphonic music, then designed encoder-decoder estimate...

Abstract Vortex generator (VG) is a passive flow control technology, which can effectively inhibit separation. Recently, significant research efforts have been devoted to the study on application of VG in airfoil, wing/blade and aircraft separation inhibition. However, variable height distribution along wingspan still lacks. This focuses experimental investigation influence ramp aerodynamic characteristics. First, was designed, such that it composed two parts, one fixed region deformed...

We propose a new framework for automatic image annotation (AIA) of regions through segmentation based semantic analysis and discriminative classification. Given test image, it is first segmented by proposed texture-enhanced JSEG algorithm. Then these are represented an extended bag-of-words model in which feature vector, on visual lexicon with its vocabulary consisting word or co-occurrence multiple words, constructed to represent the region content. Finally concept classifier learned...

Abstract Dynamic stall under large Reynolds numbers and reduced frequencies has a significant effect on the performance of wind turbine blades, helicopter rotors, etc. So dynamic physics NACA0012 airfoil number Re = 1.5 × 10 6 was studied using experimental numerical methods. The frequency range k 0.035 – 0.1. unsteady flow field in detail by transient pressure measurement simulation based Reynolds-averaged Navier-Stokes (URANS) equation. And time-frequency characteristics were wavelet...

In this paper, the effect of Gurney flap shapes on wind turbine blade airfoil S809 has been studied by numerical simulation. First, O-type grid is used in By comparing with experimental data, such as lift force, drag coefficient, and pressure distribution, accuracy simulation method validated. Second, research widths three kinds rectangular flaps at trailing edge carried out. Rectangular can considerably increase both linear nonlinear sections, maximum coefficient be increased 20.65%....

Sleep disorders refer to physiological and psychological states that cause adverse consequences due the inability fall asleep or poor sleep quality. The prevalence of varies greatly in different countries regions causes. This study aimed investigate influencing factors among preschool children Urumqi city, China.A cross-sectional was conducted with stratified random cluster sampling. Children aged 3-6 years old one kindergarten randomly selected from each 8 districts March July 2022, their...

Abstract Wind tunnel corrections are investigated for two‐dimensional low‐speed wind tests that performed three similar airfoils angles of attack ranging from −180° to 180° at Re = 0.75 × 10 6 . Aided by the Blasius theorem, deduced lift, drag and pitching moment airfoil high attack. The wall pressure signature method is applied determine strengths equivalent singularities. wall‐induced force obtained calculating exerted on maximum correction determined be about 50%. corrected forces moments...

Abstract Dynamic stall, which has a significant effect on the aerodynamic performances of dynamic airfoils, is closely related to physics stall vortex (DSV). The DSV NACA 0012 airfoil was experimentally studied using unsteady pressure measurements with high time accuracy. experimental Reynolds number Re = 1.5 × 10 6 , and reduced frequency k 0.069. propagation field during process analyzed in detail. motion characteristics were examined, including its near-wall development evolution...

Data-driven methods for melody extraction from polyphonic music generally require large amounts of labeled data model training. However, musical with annotations fundamental frequency (F0) are rare and hard to obtain. To overcome this limitation, in paper we propose use MIDI files, which more massively available, as the sources labels train a deep neural network (DNN) extraction. For each testing audio, pitch sequence estimated by DNN is comprised note numbers quantized at semitone level,...

Image segmentation is one of the most crucial techniques in computer vision. In this paper, we propose an improved approach for color image segmentation, Texture clustering based JSEG (T-JSEG). The T-JSEG combines texture information with classical algorithm. We use Gabor feature to produce map and combine it achieve a new J value computing. result by adding JSEG. Experiments on natural images Berkeley Segmentation Database verify that our method very effective more accurate boundaries...

Studying the scale effect of dynamic airfoil is helpful for understanding stall phenomenon and unsteady wall interference. In this paper, characteristics National Advisory Committee Aeronautics 0012 was studied using time-resolved pressure measurements first time, which different from Reynolds number as experimental not varied. The evolution field vortex development on scaled models investigated. Significant effects were observed during its stall. With model increases c = 500 to 900 mm,...

In this study, the aerodynamic performance of bionic airfoil was numerically studied by CFD method. The represented combination and a small trailing edge flap. A variety configurations were calculated to study effect flap parameters, such as angle, position, shape, on characteristics based two layouts which that (1) there tiny gap between (2) no two. results showed angle position had significant effects with layouts. Compared clean airfoil, maximum lift coefficients first layout second could...