Affective EEG-Based Person Identification Using Channel Attention Convolutional Neural Dense Connection Network

In the biometric recognition mode, the use of electroencephalogram (EEG) for biometric recognition has many advantages such as anticounterfeiting and nonsteal ability. Compared with traditional biometrics, EEG biometric recognition is safer and more concealed. Generally, EEG-based biometric recognition is to perform person identification (PI) through EEG signals collected by performing motor imagination and visual evoked tasks. The aim of this paper is to improve the performance of different affective EEG-based PI using a channel attention mechanism of convolutional neural dense connection network (CADCNN net) approach. Channel attention mechanism (CA) is used to handle the channel information from the EEG, while convolutional neural dense connection network (DCNN net) extracts the unique biological characteristics information for PI. The proposed method is evaluated on the state-of-the-art affective data set HEADIT. The results indicate that CADCNN net can perform PI from different affective states and reach up to 95%-96% mean correct recognition rate. This significantly outperformed a random forest (RF) and multilayer perceptron (MLP). We compared our method with the state-of-the-art EEG classifiers and models of EEG biometrics. The results show that the further extraction of the feature matrix is more robust than the direct use of the feature matrix. Moreover, the CADCNN net can effectively and efficiently capture discriminative traits, thus generalizing better over diverse human states.

Large-Scale Particle Image Velocimetry for Estimating Vena-Contracta Width for Flow in Contracted Open Channels

This paper presents the findings of a flume study using large-scale particle velocimetry (LSPIV) to estimate the top-width of the vena contracta formed by an approach open-channel flow entering a contraction of the channel. LSPIV is an image-based method that non-invasively measures two-dimensional instantaneous free-surface velocities of water flow using video equipment. The experiments investigated the requisite dimensions of two essential LSPIV components—search area and interrogation area– to establish the optimum range of these components for use in LSPIV application to contractions of open-channel flows. Of practical concern (e.g., bridge hydraulics) is flow contraction and contraction scour that can occur in the vena contracta region. The study showed that optimum values for the search area (SA) and interrogation area (IA) were 10 and 60 pixels, respectively. Also, the study produced a curve indicating a trend for vena-contracta width narrowing with a variable ratio of approach-channel and contracted-channel widths and varying bed shear stress of approach flow.

Determining the maximum sediment dispersion in an ocean disposal site for dredged material in Buenaventura, Colombia

This paper presents an analysis of the affected area at an ocean disposal site, in terms of sediment dispersion, as a consequence of the dis-posal of dredged material from the approach channel for Buenaventura´s Port. The analysis was carried out at three points within Buenaven-tura´s Bay, one located at the authorized disposal site, a second point at a proposed future disposal site and a third point at the Bocana Sector, where the highest tidal velocities are identified. The PTM (Particle Tracking Model) mathematical model was used for this investigation, showing that due to the hydrodynamic conditions, a sediment particle can reach a longer dispersion distance from its original disposal point. Finally, sediment dispersion at the three analysis points were compared in terms of current velocity and maximum displacement.

Influence of Unsteady Flow Induced by a Large-Scale Hydropower Station on the Water Level Fluctuation of Multi-Approach Channels: A Case Study of the Three Gorges Project, China

Unsteady flow induced by hydropower stations exerts a significant impact on the water level in multi-approach channels, which directly threatens the safe passage of ships. In this study, a one-dimensional and a two-dimensional hydrodynamic model are adopted to simulate the water level fluctuations at the entrance of multi-approach channels and the lower lock head of a ship lift with consideration of initial water surface elevation, base flow, flow amplitude, regulation time, and locations of hydropower stations, unfavorable conditions are successfully identified; and the fluctuations at the approach channel entrance and the lower lock head of a ship lift under single-peak and double-peak regulating mode are analyzed considering the flow regulating of the Gezhouba Hydropower Station (GHS), thus, the water level oscillation process in the multi-approach channels is presented. Results show that the largest wave amplitude in the multi-approach channels manifests under unfavorable conditions including lower initial water surface elevation, smaller base flow, larger flow variation, and shorter regulation time; and water level fluctuation in the multi-approach channel is primarily induced by flow amplitude and net flow between the Three Gorges Hydropower Station (TGHS) and the GHS, with consideration of the counter-regulation process of the GHS. This research contributes to providing a reference for a similar large-scale cascade hydropower station regarding regulation and control of navigation conditions.

Іmprovement of protection dam of the мarine approach channel Danube-Black Sea

One of the important tasks for Ukraine is to restore navigation on the mouth of the Danube Bistre, using it as a European-Asian way from the Baltic Sea to the Black Sea, and then to the East. Restoration of the deep-sea navigation of the Danube-Black Sea River has begun about ten years ago and has been progressing with great difficulty and interruptions. A protective enclosing dam of the Maritime approach channel of the Danube-Black Sea deep-water vessel was built in the water area of the Bystre estuary of the Kiliya Delta of the Danube River. This paper presents the results of mathematical and physical modeling of the improvement and reconstruction of the protection dam of the Maritime approach channel of the Danube-Black Sea deep-sea navigation. Numerical calculations of the transformation of wind waves in the water area near the dam for the most dangerous wind directions in stormy conditions are carried out. For mathematical modeling, the maximum values of wind and wave height were used, which were observed during the entire research period in the area of the dam. Within the framework of refraction theory, wave transformation calculations were performed for the most wave-dangerous directions of wind acceleration, namely, northeast, east, southeast and south wind directions. The results of calculations show that the construction of a protective dam at the exit of the Bystre estuary leads to a significant reduction in wave heights (almost twice) and their lengths by more than 1.5 times, which will ensure a smooth approach and exit of vessels to the Bystre estuary. To assess the characteristics of storm surges and wind waves in the study area was set "hypothetical" storm, when uniform in space and constant in time wind blows over the entire Black Sea. Simulations of wind waves were performed by the 3-step method of nested grids. Calculations were performed for twelve options directly. The morphodynamic calculations showed the areas of circulating near bottom currents inside the dam protected area and the peculiarities of the bottom deformation due to wave motion and storm rise of sea level. Experimental studies on a fragment of the dam model revealed the areas of greatest wave loads, features of wave transformation and pressure fields on the dam ridge. On the basis of theoretical and experimental researches the new step form of the dam which withstands storm wave loads is proposed.

Capacity Analysis for Approach Channels Shared by LNG Carriers

The transport of liquefied natural gas (LNG) has significant impact on traffic capacity of waterways, especially the approach channels shared by LNG carriers and other types of ships (general cargo ships, container ships, etc.). Few studies take the behavioral characteristics of LNG carriers and their impacts into consideration. In this paper, we propose a framework for capacity analysis of shared approach channels based on the spatial–temporal consumption method. It consists of three modules: (1) the tide module predicts the tidal height and tidal time for identifying the time windows for LNG carriers; (2) the spatial–temporal consumption module is introduced to calculate the capacity of approach channels; (3) the LNG carrier navigation module is for analyzing the characteristics of LNG carriers and the impact on the capacity of approach channels. A spatial–temporal indexed chart is designed to visualize the utilization of the spatial–temporal resources. A case study on the approach channel of Yueqing Bay near the east coast of China is conducted to verify the effectiveness of the framework. The utilization rates of the approach channel and the impact of LNG carriers are presented using our method. The results of the case study indicate that the proposed traffic capacity analyzing framework can provide support for making traffic management strategies.

Conditions of Safe Ship Operation in Seaports – Optimization of Port Waterway Parameters

A seaport is presented in this article as a system composed of various types of waterways. The author has defined relationships between port waterway system elements and conditions of safe operation of ships in port. Relationships were determined between the conditions of safe operation of ships and the parameters of the following port waterways: anchorage, fairways (approach and inner channels, port entrances), turning area and port basin. The identified relationships between port waterway system and conditions of safe ship operation provided a basis for formulating the objective function of waterway parameter optimization during port design. In practice, these relations were used to determine the parameters of the Outer Container Terminal being built in Świnoujście, where two optimization problems were to be solved: The optimization of approach channel parameters, The optimization of parameters of the port entrance, turning area and port basin. The Outer Container Terminal in Świnoujście is expected to handle ocean-going ships with a length overall Lo = 400 m, and its projected capacity is estimated at 1.5 million TEU per year, a figure that can be doubled in the future.

Short-Term Multi-Objective Optimal Operation of Reservoirs to Maximize the Benefits of Hydropower and Navigation

Traditional reservoir operation mainly focuses on economic benefits, while ignoring the impacts on navigation. Thus, the economic operation of reservoirs considering navigational demands is of great significance for improving benefits. A navigation capacity evaluation method (NCEM), which evaluates the navigation capacity considering the influence of flow velocity and water level variation on navigation, is proposed to more effectively evaluate the navigation capacity. Based on two-dimensional hydrodynamic numerical simulation, the NCEM accurately calculates the navigation capacity according to detailed flow velocity and water level changes. In addition, a short-term multi-objective optimal operation model considering the upstream and downstream navigation and power generation is established. Then, the Strength Pareto Evolutionary Algorithm (SPEA2) is used to solve the model. To verify the rationality of the method and model, they are applied to the case study of the Xiangjiaba reservoir. The results demonstrate that the method and model can not only provide a series of operation schemes for decision makers of reservoirs, but also direct the ship to pass safely through the approach channel, implying a certain practical value and significance as a reference for the short-term optimal operation of reservoirs in the future.

Port Channel Navigation Subjected to Environmental Conditions Using Reinforcement Learning

This paper proposes a machine learning agent for automatically navigating a vessel in a confined channel subject to environmental conditions. The agent is trained and tested using a Ship Maneuvering Simulator and is responsible for commanding the rudder, so as to keep the vessel inside the channel with minimum distance from the center line, and to reach the final part of the channel with a prescribed thruster rotation level. The algorithm is based on deep reinforcement learning method and uses an efficient state-space representation. The advantage of using reinforcement learning is that it does not require any expert to directly teach the agent how to behave under particular conditions. The novelty of this work is that: it does not require previous knowledge on the vessel dynamic model and the maneuvering scenario; it is robust against fluctuations of environmental forces such as wind and current; it considers discrete actions of rudder commands emulating the pilot actions in a real maneuver. The developed method is convenient for simulations in scenarios or areas that were never navigated before, in which no previous navigation data can be used to train a conventional supervised learning agent. One direct application for this work is the integration with a realistic fast-time maneuvering simulator for new ports or operations. Both training and validation experiments focused on the unsheltered approach channel of the Suape Port, in Brazil; these experiments were run in a SMH-USP maneuvering simulator (real environmental conditions measured on-site were employed in simulations).