The purpose of this study is to investigate the current status metal pollution sediments from urban-stream, estuary and Jinzhou Bay coastal industrial city, NE China. Forty surface sediment samples river, bay one core were collected analyzed for heavy concentrations Cu, Zn, Pb, Cd, Ni Mn. data reveals that there was a remarkable change in contents metals among sampling sediments, all mean values concentration higher than national guideline marine quality China (GB 18668-2002). This most...

Fast and accurate forecasting of unsteady flow is a challenge for both fluid dynamics machine learning study. In this paper, hybrid network-operator model proposed to predict the spatiotemporal flow. The first integrates Fourier neural operator (FNO) convolutional long short-term memory (ConvLSTM) network in parallel. systematically evaluated three typical problems, including two-dimensional turbulence, around stationary cylinder, an oscillated airfoil. Numerical experiments indicate that...

Abstract This study conducted a numerical simulation of the gas leakage process in space station based on thermodynamic and fluid dynamic models, aiming to explore variations pressure temperature under different leak aperture conditions. The research first established mathematical model describing inside station, assumptions ideal behavior uniform distribution. It introduced effects adiabatic expansion radiative cooling, constructing system differential equations for changes. Through...

In this letter, a novel algorithm for attitude measurement based on 3-D electromagnetic model (3-D em-model) is proposed. The em-model established offline the geometric structure of target, and it can be used to predict scattering features at different target attitudes. order measure air we design bistatic step frequency radar system. directions two radars' lines sight (LOSs) relative are acquired by matching high-resolution range profiles (HRRPs) from echoes HRRPs generated em-model. Since...

Spatiotemporal visualization of instantaneous flame structures in a hydrogen-fueled axisymmetric supersonic combustor was investigated using multiview planar laser-induced fluorescence the hydroxyl radical, coupled with high-speed photography and pressure measurement. The cavity generates loop-shaped recirculation flow shear layer that sustains flame. An irregular wrinkled loop central hole is formed near region. Due to turbulent disturbances, multiple small-scale holes fragmented flames are...

The position of RFID-tagged objects in sensor networks is becoming an important feature for ubiquitous computing applications. In this work, we develop improved positioning algorithm objects. Compared with the VIRE algorithm, apply a nonlinear interpolation method to further improve precision. We also introduce concept credibility reference tags reduce influence abnormal on Finally, provide detailed simulations evaluate proposed technique.

ABSTRACT Phonemic restoration, a form of temporal induction, occurs when the human brain compensates for masked or missing portions speech by filling in obscured nonexistent sounds. We tested induction and related abilities females Gray Treefrog Hyla versicolor. The number pulses calls is used assessment males. Accordingly, an ability to “restore” interpolate between otherwise sonically degraded could help during mate choice noisy choruses. In phonotaxis experiments, we employed unmodified...

Film cooling via tangential wall injection is universally employed to alleviate serious aerodynamic heating of the optical window in high-speed target-seeking vehicles; nevertheless imaging quality should be concomitantly concerned due turbulence-aberrated aero-optical phenomenon. This flow phenomenon can essentially abstracted into combinational mixing layer and turbulent boundary configuration, enabling numerical investigation using an explicit fifth-order weighted compact nonlinear scheme...

Accuracy, robustness, and efficiency are the three major goals of turbulence closure. Generally, eddy-viscosity models (EVMs) with Boussinesq approximation numerically stable efficient. However, accuracy EVMs for aerodynamically complex configurations is inadequate. Reynolds-stress (RSMs) perceived as most advanced models, but their robustness could be improved. Here, a hybrid closure proposed that combines novel equation six equations. The natural boundary conditions on walls designed to...

A novel design approach for active shimming coils superconducting magnets is proposed to compensate the previous ten components of field deviation. The analytic method first used obtain topologies various order fields and establish a coil model. Then particle swarm optimization adopted optimize parameters, deviation magnetic taken as fitness function minimization bias field. results from are reference set initial value ranges parameters. have shown that, compared with traditional method,...

Aero-optical reduction in flat-plate turbulent boundary layer has been widely concerned due to critical application for high-speed target-seeking vehicles. From the perspective of disciplinary intersection between aerodynamic and optical engineering, turbulence-aberrated behaviour, high-Reynolds-number supersonic freestream, is numerically investigated using in-house code High-Order SimulaTor Aerodynamics (HOSTA) ray-tracing scheme. To evaluate efficiency wall cooling strategy reduce...

The energy concept sheds light upon the hydraulic system that comprises throttled surge tank, tunnel and penstock. mathematical manipulation of governing differential equations water hammer yields an (power) equation in point form. By integration with respect to pipe distance, this relation is extended first individual pipe, then surge-tank branching connection. states relationship between total (internal plus kinetic) energy, convective work done on dissipation. A case study identifies...

The flow past a cylinder is classical problem in physics. In certain range of Reynolds number, there will be Karman vortex street phenomenon the wake cylinder, which greatly increase pressure drag cylinder. By controlling shedding phenomenon, reduction could effectively realized. this paper, NACA0012 airfoil with pitching oscillation placed downstream Based on tight coupling method, kinematics equations and Navier–Stokes arbitrary Lagrangian–Eulerian form are solved. Firstly, effect period...

Wireless positioning in indoor environment is growing rapidly with the development of location based services. Among these technologies, fingerprinting has been widely used, and its performance satisfactory precision requirement. The radio-map key to positioning. However, once application scenarios changed, doesn't get updated time, will be seriously affected. In this work, we develop a novel adaptive for RSS-based Firstly, collected signal characteristics plurality reference points checked...