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The influence of a masker on localization of a sound signal in the vertical sagittal plane was studied in conditions of masking using simultaneous masking and the paradigm of the precedence effect. In the first case, a stationary signal and a masker were presented simultaneously, while in the second, signal onset was shifted relative to masker onset. Shift values (delays) were 2, 4, 8, 20, 40, 80, and 200 msec. Uncorrelated noise pulses with a bandwidth of 5–18 kHz were used as signal and masker. Noise pulse duration was 1 sec. The masker was always presented at an angle of 90° elevation (above the listener’s head) and the signal from a position of 7.5° elevation (in front of the listener relative to the interaural line). The perceived angular position of the signal in masking conditions was compared with spatial estimates of the same signal when presented in isolation (without a masker); similarly, localization of the masker in masking conditions was compared with the perceived position of an isolated masker (without a signal). Signal detection probability was found to decrease in masking conditions. At delays of 0–40 msec, listeners mainly identified the perceived position of the masker, which was shifted towards the signal regardless of the delay value and was significantly different from the perceived position of the isolated masker. Signal localization probability at these delays was no more than 8%. At delays of 80 msec and longer, signal localization probability increased to 92% and more. Perceived signal position did not depend on delay duration and was not significantly different from the position of the isolated signal.

To improve the vertical plane motion performance of an underwater vehicle with bow and stern elevators under actuator saturation and external disturbance conditions, a new control method is proposed in this paper. Firstly, for simplifying the analysis of the coupled kinetics equation of the underwater vehicle, virtual control variables are introduced to decompose the kinetics equation into two cascaded components. Then, a framework consisting of control law and control allocation is presented according to the cascaded components. In the aspect of control law, a double closed-loop control scheme is designed. The outer loop realizes the depth control by adjusting the expected heave velocity and pitch of the underwater vehicle with an S-plane regulator and a subsection function. Meanwhile, an Augmented Linear Quadratic Regulator (ALQR) is employed in the inner loop to control the heave velocity and pitch without steady-state error. Considering the physical constraints of elevators, a pitching-priority idea is adopted in the design of the control allocation to prioritize the pitch control requirement of the underwater vehicle. Finally, based on the framework, disturbances are estimated and compensated to enhance the anti-interference performance, as well as, auxiliary functions are constructed for reducing the adverse effect caused by saturation. Simulation results show that the new control method performs perfectly under various conditions, it is also conducive to the navigation safety of the underwater vehicle because of its superior pitch control capability.

The wind wave erosion is one of the main factors of the soil bank slope retreat in plain irrigation reservoirs, which plays an important role in the bank profile evolution and seriously affects the agricultural irrigation. To study the failure mechanism induced by the wind wave erosion, a reservoir soil bank slope is taken as a research object. Through the field investigations, laboratory tests and prototype observations, a mechanical model of the bank slope recession under the wind wave erosion is established and verified by the field observation results. On this basis, the finite element method is utilized to analyze its stability in different erosion periods, and the evolution law of the safety factors with erosion time is revealed quantitatively. The results show that the lateral retreat of the slope foot will lead to local collapse and form vertical surfaces when eroded by wind waves. Based on the monitoring data in April 2019, the calculated lateral erosion distance is 1.29 m after the wind wave erosion lasts for 9 h, and the vertical surface height reaches 3.10 m, resulting in the bank slope failure. After failure, it is reshaped, and the stability is significantly improved. However, the new slope will face the instability risk of the former one when eroded by wind waves again. The stability safety factors generally show cyclical variation with the wave erosion time. The failure and retreat of the bank slope repeat the above cycle annually.

Various climbing plants can be selected as an element in the vertical greenery system. However, it should consider the species’ suitability to climb any vertical structure. This study aims to analyze the growth rates of several climbing plants in a vertical plane at different hole sizes of a wire mesh. The experimental design used in this experiment was a split-plot factorial randomized block design that consisted of two factors with three replications. The species factor consisted of Antigonon leptosus Hook, Clerodendrum thomsomniae Balf. f, and Thunbergia grandiflora Roxb., while the mesh (hole) size factor consisted of 4 cm and 6 cm. Galvanized wire mesh was used as a vertical plane, while the plane dimension in each experimental unit was 3 m in height and 0.5 m in width. The research results found the best treatments obtained in the growth of A. leptopus in a mesh size of 4 cm. A combination of A. leptopus in a mesh size of 4 cm produced the highest value in plant height, the number of leaves, the percentage of plant coverage, and increasing of flowers number. T.grandiflora and C.thomsoniae ranked second and third in growth rate, respectively

The vibrations of a three-section boom of a concrete pump in the vertical plane on a three-mass dynamic system are considered separately from the torsional vibrations of the boom and its vibrations in the horizontal plane. The differential equations are based on the generalized Hooke law. The values of the periods of natural oscillations of the boom T 1 = 1.33 s, T 2 = 0.32 s, and T 3 = 0.132 s and the corresponding forms of these vibrations are given. It has been shown that when the pump performance is close to the maximum, resonance at a low frequency is possible. Some positions and modes of operation of the boom are considered, in which significant additional dynamic loads may arise in its middle section. Recommendations are given on ways to reduce the dynamics of a concrete pump boom in the vertical plane.

When a submarine encounters an emergency situation, it should take emergency-surfacing actions by moving upward with a large angle of attack in the vertical plane. Previous research has often neglected the effect of vertical plane motion on the lateral force (Fy), rolling moment (Mx), and yawing moment (Mz). To examine the flow characteristics of submarines at high angles of attack on the vertical plane, the SST-DDES method is adopted in conjunction with adaptive mesh refinement (AMR) technology, and the new Omega vortex detection method is employed as the AMR criterion for numerical calculations. The obtained results are then appropriately verified by conducting water tank experiments, and the effects of different angles of attack and heel angles on Fy, Mx, and Mz are methodically examined. The results reveal that, in the flow around the vertical plane of a submarine, the influence of Fy and Mz cannot be ignored. In addition, when the vertical velocity of the hull is greater than 0.6 m/s, the influence of Mx cannot be overlooked either. When the angle of attack on the vertical plane of the submarine is greater than 25°, the effects of Fy, Mx, and Mz cannot be neglected, and the effect of Mz is particularly prominent, with its amplitude close to or greater than the average value of the pitch moment (My). The obtained results reveal that the presence of the heel angle (θ) intensifies the forces on the hull for Fy, Mx, and Mz, and the forces caused by the vertical velocity at Fy, Mx, and Mz cannot be neglected. These findings can provide a mechanical analysis basis for the analysis of nonlinear motion phenomena during submarine surfacing.

The maneuverability of a submarine in the vertical plane is a key indicator of navigation safety. However, existing studies typically evaluate maneuvering performance based on hydrodynamic coefficients, often neglecting the flow-field evolution induced by different steering strategies. In this study, a high-fidelity numerical model for the vertical-plane motion of the DARPA SUBOFF submarine is established using the Reynolds-Averaged Navier–Stokes (RANS) method and validated against benchmark data. Unlike traditional analyses that employ a fixed rudder angle, this work systematically compares three steering strategies with continuously varying rudder angles—trapezoidal, step, and linear steering—examining their motion responses, hydrodynamic performance, and unsteady flow-field evolution. The results show that, although step steering produces the fastest response with the strongest transient characteristics, it also triggers pronounced flow separation and significant unsteady effects. Linear steering yields a smoother but the weakest motion response, with reduced rudder effectiveness and a noticeable lag effect. In contrast, trapezoidal steering maintains a stable flow field around the submarine, with uniformly concentrated vorticity distribution, ensuring smooth and safe motion and achieving a favorable balance between response speed and flow stability. The findings provide theoretical reference for research on submarine vertical-plane steering motion, rudder-angle control, and flow-field stability.

This article presents an innovative, two-stage railway track model, which takes into consideration the rotation of railway sleepers due to non-uniform loads on rails. Examples of determining the dynamic response of the railway track are provided. The calculations were performed for a curve, in which non-uniform loads on rails result from the distribution of vertical loads at different train speeds. The analysis was performed using a variable moment of inertia of a sleeper.

Autonomous unmanned air vehicles (UAVs) are critical to current and future military, civil, and commercial operations. Despite their importance, no previous textbook has accessibly introduced UAVs to students in the engineering, computer, and science disciplines--until now. Small Unmanned Aircraft provides a concise but comprehensive description of the key concepts and technologies underlying the dynamics, control, and guidance of fixed-wing unmanned aircraft, and enables all students with an introductory-level background in controls or robotics to enter this exciting and important area. The authors explore the essential underlying physics and sensors of UAV problems, including low-level autopilot for stability and higher-level autopilot functions of path planning. The textbook leads the student from rigid-body dynamics through aerodynamics, stability augmentation, and state estimation using onboard sensors, to maneuvering through obstacles. To facilitate understanding, the authors have replaced traditional homework assignments with a simulation project using the MATLAB/Simulink environment. Students begin by modeling rigid-body dynamics, then add aerodynamics and sensor models. They develop low-level autopilot code, extended Kalman filters for state estimation, path-following routines, and high-level path-planning algorithms. The final chapter of the book focuses on UAV guidance using machine vision. Designed for advanced undergraduate or graduate students in engineering or the sciences, this book offers a bridge to the aerodynamics and control of UAV flight.

This paper presents the modeling of a new ray-type hybrid underwater glider (RHUG) and an experimental approach used to robustly and adaptively control heading motion. The motions of the proposed RHUG are divided into vertical-plane motions and heading motion. Hydrodynamic coefficients in the vertical-plane dynamics are obtained using a computational fluid dynamics (CFD) method for various pitch angles. Due to the difficulty of obtaining accurate parameter values for the heading dynamics, a robust adaptive control algorithm was designed containing an adaptation law for the unknown parameters and robust action for minimizing environmental disturbances. For robust action against bounded disturbances, such as waves and ocean currents, sliding mode control was applied under the assumption that the bounds of the external disturbances are known. A direct adaptive algorithm for heading motion was applied in an experiment. Computer simulations of the proposed robust adaptive heading control are presented to demonstrate the robustness of the proposed control system in the presence of bounded disturbances. To verify the performance of the proposed controller for heading dynamics, several heading control experiments were conducted in a water tank and in the sea.