Forces acting on the forearm and hand during swimming can be decomposed into drag forces and lift forces. In this study drag and lift forces were measured on two models of a human hand and forearm when towed in a towing tank. To compare the results of models with different size at different velocities force data were normalized to drag and lift coefficients (Cd and Ct). Influence of the orienta...

The time reversal mirror technique has been widely applied to mitigate the inter-symbol interference in underwater channels. Meanwhile, an adaptive time reversal mirror is introduced to improve the crosstalk quality between receivers in underwater acoustic communication (UAC). However, array configuration affects the performance of this mechanism. To explore the effectiveness of this method, th...

Štúdium viazania stopových prvkov v sedimente vodnej nádrže Ružín Pre účely posúdenia možnosti využitia fyzikálnych a fyzikálno-chemických metód separácie, vybraná vzorka sedimentu z Ružína bola podrobené 5-stupňovej procedúre sekvenčnej extrakcie (SE) podľa Tessiera (Tessier et al., 1979) a Horowitza (Horowitz, 1991). Vo výluhoch bolo stanovované zastúpenie konštitučných (Fe, Mn, Ca a Mg) ako ...

Abstract A velocity vector profile technique based on an ultrasound pulsed Doppler method can enrich the information flow field. However, it has shown low availability because a new design of special transducers is required for each measurement case. This study proposes profiling vectors using conventional that are widely supplied to users. We constructed configuration minimize uncertainty dete...

The wake waves generated by the steady movement of a planing hull are analyzed means towing tank tests. Two sets waves, including divergent and transverse identified then analyzed. wave period is seen to decrease increase in speed vessel. These damp temporally. mechanisms that lead damping were found depend on orbital Reynolds number semi-planing regime, though in-planing regime function boat. ...

This paper experimentally investigates the flow field development and unsteady loading of three force-mitigating pitch manoeuvres during a transverse gust encounter. The are constructed using varying levels theoretical simulation fidelity implemented as open-loop kinematics in water towing tank. It is found that actuation encounter results two important changes topology: (i) early detachment le...

Ocean surface wave environment due to its randomness has mostly been analyzed and understood from a statistical way. Accurate reliable prediction is the basic guarantee for ocean transportation offshore operation. However, significant nonlinearity of in real sea will result simulation challenge. To solve problem, this paper proposes Deep Learning instantaneous model based on Convolutional Neura...

In this paper, we address the cooperative towing of payloads by multiple mobile robots in the plane. Robots are attached to a planar object or a pallet carrying a payload by cables. Coordinated motion by the robots allow the payload to be manipulated through a planar, warehouse-like environment. We formulate a quasi-static model for manipulation and derive equations of motion that yield the mot...

This work discusses the correct modeling of fully nonlinear free surface boundary conditions to be prescribed in water waves flow simulations based on potential theory. The main goal such a discussion is that identifying mathematical formulation and numerical treatment can used both carry out transient simulations, compute steady solutions — for any admitting them. In literature towing tank fac...

Abstract This paper investigated the resistance performance of a submersible surface ship (SSS) in different working cases and scales to analyze hydrodynamic characteristics an SSS at speeds diving depths for engineering applications. First, hydrostatic test was carried out towing tank. Second, scale effect pressure coefficient wave-making analyzed. The differences between three-dimensional rea...