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Located in the southeast of Hue city in Thua Thien Hue province, Thuan An estuary plays a crucial role as a waterway and flood drainage pathway for the Huong River. Importantly, the morphology of the Thuan An estuary has been subjected to continuous change during monsoon seasons with the process of sediments in the estuary and erosion along the northern and southern coasts. Remarkably, the process of sediments directly impacts flood drainage and navigation along the waterway, as well as the sustainable development of Thua Thien Hue marine economy. Therefore, the goal of this study is to insightfully provide hydrodynamic regimes using a Delft3D model combined with ArcGIS software. The results showed that the estuary is wave-dominated lowland coasts. The coastal barrier is formed from sand that is transported along the shoreline by wave-driven longshore currents. During the northeast monsoon, river flow is significantly small, tidal currents combine with longshore currents by waves to form a strong longshore current with direction from northeast to southwest. Whereas, during the southwest monsoon, the sandbar extending from the southern side expands northward, leading to sedimentation accumulation at the river mouth channel. Specifically, a sandbar is formed at the river mouth with an accumulation of up to about 0.8 m. [ABSTRACT FROM AUTHOR]

Like many post-industrial urban waterways, Manchester's River Irk was once central to the lives of the communities it flowed through. Over the past century, however, it has been built over, culverted, neglected, and, according to one recent council report, become 'culturally lost'. Daylighting, the re-opening of lost urban rivers to promote biodiversity, flood prevention, and community access, is a growing global movement. But simply revealing rivers is not enough. In order to fully restore a river, it is also vital to reclaim it in people's imaginations, creating new knowledge which draws upon the stories, folklore, and history flowing through it. This article investigates how co-produced creative writing workshops with community groups along the Irk can unearth and develop stories connected to rivers and reconnect people to lost waterways. In doing so, the article aims to encourage a place-making model which empowers marginalized communities to influence future riverside development. [ABSTRACT FROM AUTHOR]

The real-time and accurate detection and ranging of ships play a pivotal role in ensuring navigation safety, this study aims to enhance the navigation safety and environmental perception capabilities of inland waterway vessels. In the ship detection stage, addressing challenges such as large parameters, high computational complexity, and poor real-time performance in existing ship detection models, this paper proposes the MS-YOLOv5s ship target detection algorithm. This algorithm, based on YOLOv5s, utilizes the lightweight MobileNetV3-Small network to replace the original YOLOv5s feature extraction backbone network, thereby improving the detection speed. The results indicate that the parameter size of the MS-YOLOv5s model is 3.55M, only 50.49% of YOLOv5s. Achieving a detection rate of 50.28 FPS, the precision is 96.80%, and the mAP is 98.40%, striking a balance between high accuracy and low computational demand. In the depth estimation stage, influenced by the environment, leading to unstable measurement data, this paper proposes a binocular Kalman filter fusion ranging algorithm. The standard deviation of the ranging results is minimized to 6.032μm, which is one order of magnitude smaller than traditional ranging algorithms, significantly enhancing the robustness of the measurement results. Within a distance of 20m from the ship target, the error can be controlled within 3%, showcasing the applicability of the method proposed in this paper in complex inland waterway environments contributes to the enhancement of ships' environmental perception capabilities and navigation safety, holding positive implications for the development of intelligent vessels. [ABSTRACT FROM AUTHOR]

In the study of natural waterways, the use of formulas such as Manning's equation is prevalent for analyzing flow structure characteristics. Typically, floodplains exhibit greater roughness compared to the main river channel, which results in higher flow velocities within the main channel. This difference in velocity can lead to increased sedimentation potential within the floodplains. Therefore, accurately determining Manning's roughness coefficient for compound channels, particularly during flood events, is of significant interest to researchers. This study aims to model the Manning roughness coefficient in compound channels with both converging and diverging floodplains using advanced soft computing techniques. These techniques include a multi-layer artificial neural network (MLPNN), Group Method of Data Handling (GMDH), and the Neuro-Fuzzy Group Method of Data Handling (NF-GMDH). For the analysis, a dataset from 196 laboratory experiments was used, which was divided into training and testing subsets. Input variables included parameters such as longitudinal slope (So), relative hydraulic radius (Rr), relative depth (Dr), relative dimension of flow aspects (δ*), and the convergent or divergent angle (θ) of the floodplain. The relative Manning roughness coefficient (nr) was the output variable of interest. The results of the study showed that all the models performed well, with the MLPNN model achieving the highest accuracy, characterized by R² = 0.99, RMSE = 0.001, SI = 0.0015, and DDR = 0.0233 during the testing phase. Further analysis of the soft computing models indicated that the most critical parameters influencing the results were Sr, Rr,Dr*, and θ. These findings highlight the effectiveness of soft computing techniques in accurately modeling the Manning roughness coefficient in complex channel conditions and provide valuable insights for future research and practical applications in the management of flood events and waterway analysis. [ABSTRACT FROM AUTHOR]

As the basis for characterizing traffic conditions in waterways, fundamental characteristics of waterway traffic streams are of great practical significance in ensuring traffic safety and improving navigation efficiency. In the study of the fundamental characteristics of waterway traffic flow, although some scholars consider the length or area of the vessel, few scholars take the displacement of the vessel into account and make light of the influence of the three-dimensional size of the vessel. This paper proposes a method for defining the fundamental characteristics of a waterway traffic stream considering vessel size. This method defines fundamental characteristics in terms of vessel displacement and quantifies flow, density, and speed based on vessel trajectories in time–space regions. This study selects a unidirectional channel in the south trough waters of Shanghai Harbor for a case study and draws the fundamental diagram of the waterway traffic stream while considering vessel number and displacement. The comparison result shows that the definition considering vessel displacement can more accurately reflect the actual traffic condition of the selected channel. Finally, based on the flow–density subgraph of the waterway traffic stream (measured by vessel displacement), this paper constructs a traffic stream model and derives critical parameters. The definition proposed in this study effectively characterizes how vessels occupy the time–space resources of waterways, revealing the inherent mechanisms governing waterway traffic stream and, thus, enhancing accuracy in describing fundamental relationships among waterway stream characteristics. The outcome of this research underlies how the waterway traffic stream is measured, operated, and managed to ensure safety and productivity. [ABSTRACT FROM AUTHOR]

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Primary waves produced by large ships in confined waterways can threaten the sustainability and safety of coastal regions near maritime shipping routes, but the present understanding and predictability of primary wave shallow-water characteristics is hindered by a scarcity of available field observations. This study presents hydrodynamic measurements from 296 primary waves observed in 3.5 to 4.4 m mean water depth throughout four deployments on the channel margins of the Savannah River in Georgia, USA. Ship details and tidally varying waterway parameters are paired with pressure and fluid velocity data to investigate relationships between ship characteristics, waterway conditions, and primary wave magnitudes. Findings show that although larger and faster ships tend to produce larger primary waves, there are inconsistencies among the magnitudes of waves generated by similar ship passages. Additionally, depression prediction equations perform well for most observations, but a small group of "atypically-large" primary waves with depressions exceeding 75 cm are consistently underpredicted and require further investigation. Hydrodynamic, waterway, and ship data are made available in the Supplemental Data. [ABSTRACT FROM AUTHOR]

Semantic segmentation-based Complex Waterway Scene Understanding has shown great promise in the environmental perception of Unmanned Surface Vehicles. Existing methods struggle with estimating the edges of obstacles under conditions of blurred water surfaces. To address this, we propose the Lightweight Dual-branch Mamba Network (LDMNet), which includes a CNN-based Deep Dual-branch Network for extracting image features and a Mamba-based fusion module for aggregating and integrating global information. Specifically, we improve the Deep Dual-branch Network structure by incorporating multiple Atrous branches for local fusion; we design a Convolution-based Recombine Attention Module, which serves as the gate activation condition for Mamba-2 to enhance feature interaction and global information fusion from both spatial and channel dimensions. Moreover, to tackle the directional sensitivity of image serialization and the impact of the State Space Model's forgetting strategy on non-causal data modeling, we introduce a Hilbert curve scanning mechanism to achieve multi-scale feature serialization. By stacking feature sequences, we alleviate the local bias of Mamba-2 towards image sequence data. LDMNet integrates the Deep Dual-branch Network, Recombine Attention, and Mamba-2 blocks, effectively capturing the long-range dependencies and multi-scale global context information of Complex Waterway Scene images. The experimental results on four benchmarks show that the proposed LDMNet significantly improves obstacle edge segmentation performance and outperforms existing methods across various performance metrics. [ABSTRACT FROM AUTHOR]

Simulation technology has been extensively utilized in the study of ship entry and exit from ports, as well as navigation through waterways. It effectively mirrors the stochastic dynamic changes and interrelationships among various elements within the port system. This paper provides a comparative analysis of the advantages and disadvantages of various modeling methods used in ship navigation simulations. It proposes a simulation modeling approach for ship–port systems based on multi-agent information interaction, which simulates the entire process of ships entering and exiting ports and navigating through complex waterways, achieving a precise and detailed simulation of the entire port entry and exit process in complex waters. Using the Qiongzhou Strait as a case study, the validity and accuracy of the model are verified. The model is employed to quantitatively identify port navigation elements, assess waterway capacity, and evaluate port operational capability. Furthermore, the model enables the analysis of coordination among port channels, berths, and anchorages. Based on simulation results and port development plans, recommendations are provided to enhance port service levels and promote scientific, rational development and efficient operation of ports. [ABSTRACT FROM AUTHOR]

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An investment gap in America's inland waterways (IWWs) has been fueled by decades of low investments, which has negatively impacted the reliability of the waterway's locks. US IWWs, which transport commodities and support the nation's economy, are aging rapidly, exacerbated by decades of underinvestment. Many of these infrastructure systems now need to address a substantial maintenance backlog to increase their life span and improve functionality. Optimizing the decision-making process for effective and efficient planning and policymaking is essential to perform this requisite maintenance. Recognizing the robust scope of this maintenance, long-term maintenance strategies are needed in order to optimize investments across these waterway systems to improve their condition. Currently, limited research exists on decision making on IWW transportation assets, and there is a lack of requisite guidance for optimally performing maintenance activities on a single lock on the IWW system. Therefore, this study focuses on developing a decision-making model that considers several uncertainties toward optimizing the maintenance of locks on IWWs. The model evaluates maintenance decisions on an IWW lock using data obtained via expert elicitation. Results obtained from compiling the influence diagram (ID) and performing sensitivity analysis on the model support the need for periodic inspection of the locks to assess the condition before making any maintenance decision. The study presents a novel approach for enhancing maintenance decisions on IWW assets by considering key uncertainties beyond the physical condition of the assets. This research sets the stage for further studies on how fiscal constraints affect infrastructure asset maintenance decisions. [ABSTRACT FROM AUTHOR]

In the middle of the Chesapeake Bay sits small and shrinking Tangier Island, Virginia. Home to 1,200 residents a century ago, the island now has fewer than 400 residents, a population decreasing as the land subsides into the bay. Scientists predict the island will be uninhabitable by the 2040s, while residents themselves profess to be climate change deniers and science skeptics. I examine the politics and social order of engineering interventions and their afterlives on Tangier, endlessly studied and sometimes implemented by the federal government, the Commonwealth of Virginia, and the U.S. Army Corps of Engineers. A northern channel bisecting the island, first dredged in 1966, and a seawall on the western side of the island, constructed in 1990, were both obsolete before they were created, showing the ways in which infrastructure, especially dredging of waterways, and its afterlives are channeled as processes controlled by state experts, justified by and justifying endless cascades of interventions, naturalizing the landscape, and ultimately placing Tangiermen as willing victims and imminent refugees in an uncertain crisis. [ABSTRACT FROM AUTHOR]

The difference between waterway traffic and road traffic in terms of lane lines leads to the direct application of the method of plotting the fundamental diagram of road traffic flow to waterway traffic, and it is difficult to reveal the mechanism of waterway traffic flow operations. This study proposes a shipping-lane-subdivision approach to tackle this problem. Additionally, it introduces a more suitable fundamental diagram-plotting method for waterway traffic based on the aforementioned method. The southern channel in the estuary of the Yangtze River was taken as the research water, and the fundamental diagram of traffic flow in this water was plotted to verify the similarities between the fundamental diagram of waterway traffic flow and the fundamental diagram of road traffic flow. Upon evaluating the plotted fundamental diagram, it was determined that the blockage density of the subdivided shipping lane is around 6.5 vessels per nautical mile. This method has significant potential for its application in the theory of waterway traffic flow. [ABSTRACT FROM AUTHOR]

This study presents a method to support ship trajectory prediction at waterway confluences using historical Automatic Identification System (AIS) data. The method is meant to improve the recognition accuracy of ship behavior trajectory, assist in the proactive avoidance of collisions, and clarify ship collision responsibility, to ensure the safety of waterway transportation systems in the event of ship encounters induced by waterway confluence or channel limitation. In this study, the ship trajectory based on AIS data is considered from five aspects: time, location, heading, speed, and trajectory by using the piecewise cubic Hermite interpolation method and then quickly clustered by regional navigation rules. Then, an improved K-Nearest Neighbor Algorithm considering the sensitivity of data characteristics (SKNN) is proposed to predict the trajectory of ships, which considers the influence weights of various parameters on ship trajectory prediction. The method is trained and verified using the AIS data of the Yangtze River and Han River intersection in Wuhan. The results show that the accuracy of SKNN is better than that of conventional KNN and Naive Bayes (NB) in the same test case. The accuracy of the ship trajectory prediction method is above 99% and the performance metrics of the SKNN surpass those of both the conventional KNN and NB classifiers, which is helpful for early warning of collision encounters to ensure avoidance. [ABSTRACT FROM AUTHOR]

The study reviews the essence of inland dry ports (IDPs) in Nigeria and the vital role played by inland transportation as performance-enhancing factor in the mutually complementary services of IDPs and seaports. The study adopts survey research design and used primary and secondary sources of data. Questionnaire and interview were the instruments used for sourcing primary data. Six objectives of the study centre on the problem and the study adopted the Taro Yamane formula to determine 343 as the sample size, out of study population of 1412. The study uses descriptive statistics and identifies the challenges faced by rail, road and inland waterways modes of transport in the quest to connect them to IDPs in Nigeria from interview, literature review, media reports, port operators and other stakeholders. It identifies the effects of poor port hinterland connectivity, and noted the high-cost element in transporting containers through deplorable roads to IDPs in Nigeria, which is taking its toll on the performance of the IDPs. The study recommends that Government should adopt a holistic national freight logistics strategy, which involves all tiers of government and industry, and make provision for enhanced coordinated national multi-modal and intermodal approaches to freight planning. This would facilitate the reduction of trade costs and enhance the optimization of the performance of inland dry ports in Nigeria. [ABSTRACT FROM AUTHOR]

Urbanization disrupts river networks, alters waterway connectivity, and elevates flood control pressure. Quantitatively assessing river network changes and their impact on waterway connectivity and flooding processes is imperative. We constructed a waterway connectivity evaluation model and a hydrologic–hydrodynamic model to assess the river network, the waterway connectivity and the flooding change in the Qinhuai River Basin, and used scenario analysis to determine the effectiveness of different topology changes. The results showed a 0.09 decline in connectivity from 2000 to 2010, which led to a peak occurrence time 1 h earlier, an increase in peak discharge by 2.59 m3/s and a rise in peak water level by 51 mm. Scenario analysis demonstrated that adding tributaries can enhance both connectivity and flood resilience. Increasing river width effectively reduces peak water levels while minimally affecting connectivity. Extending river length has a negligible effect on peak water levels but may decrease waterway connectivity. [ABSTRACT FROM AUTHOR]

China's coal industry has long faced challenges due to imbalance between supply and demand divisions and the discrepancies between supply and demand prices. Research on optimizing coal transfer amid fluctuating coal prices is crucial for enhancing coal resource allocation, ensuring a balanced and stable supply of coal resources, and promoting the sustainable development of the coal industry. This paper focuses on optimizing coal transfer schemes within a comprehensive transportation system, considering fixed transportation routes and opening times of railroad transportation and waterway transportation, with road transportation serving as a supplementary network. A three-dimensional spatio-temporal network model is established to represent the spatial and temporal paths and transportation modes of coal logistics. The study uses the coal transportation network from Inner Mongolia and Shaanxi to East China as a case study, analyzing factors such as coal price fluctuation, transportation rates, and the ratio of self-produced to purchased coal at the production end via sensitivity analysis. The findings indicate that the proposed model can effectively guide transportation practices under the integrated production, transportation, and sales framework in the energy industry. Additionally, it shows that enterprises can achieve higher profits and maintain revenue and supply stability despite coal price fluctuations, aligning with the coal industry's transformation and development in the current context. [ABSTRACT FROM AUTHOR]

The idea of building the Oder-Danube waterway dates back to the fourteenth century. It was one of the first in Europe envisaging a water canal of such dimensions and spanning areas of highly diverse topography. Since then, new construction ideas with an altered course of the canal and hydrotechnical solutions have been proposed. The first actual design was developed in 1719. Despite the many perceived benefits, numerous difficulties were encountered over the years and the project was ultimately abandoned. The article presents the current construction status of the Oder-Danube Canal project, analyzing and assessing the political landscape in the Czech Republic as having a critical impact on the possibility of implementing the said undertaking. [ABSTRACT FROM AUTHOR]

Ports and wharves are essential parts of the infrastructure that enable the transport of goods on inland waterways. Integrating the network of inland waterways and land modes of transport, the ports are the main hubs of the transport network, they encourage economic activities and enable the development of the region. The port of "Novi Sad" is located on the left bank of the Danube River, river km 1254, and is open to international traffic. This is an exceptional location where water corridor (VII) and Pan-European Corridor X intersect and form a hub for international communication and transport. Novi Sad port's location strength is not only of a geographical nature, it also has excellent transport links as it is only 0.3 km from the railway junction of Corridor X and 3 km from the land Corridor X. The development of the port of "Novi Sad" would be related to the growth of it's industry in the background. Considering the favorable geographical position and the growing economic activity, especially in the trade exchange with the countries that are in the Black Sea basin, the port of "Novi Sad" could achieve the status of a river-sea port in addition to it's international status. In accordance with the Water Transport Development Strategy of Republic of Serbia, the port of "Novi Sad" could be developed to the extent that it becomes competitive on the market and provides transboatment and storage services in accordance to the world standards. [ABSTRACT FROM AUTHOR]

The Paraguay River Waterway is a crucial axis for integration in South America, with a course of 3.442 km from Cáceres (Brazil) to Nueva Palmira (Uruguay). To provide the navigation, improve the safety, the reliability and efficiency of the waterway transport, for a minimum period corresponding to 90% of the year, interventions with amelioration works are necessary. Among them, dredging in critical stretches stand out, which currently present some form of obstacle to navigation, either by natural factors (widths, radius of curvature and depths) or by structures, such as bridges, and sand shoals. This paper proposes a reassessment of the current nautical dimensions based on new guidelines, assessing critical sections for depth, width, and radius of curvature. The aim is to increase safety and study the feasibility of expanding the waterway by accommodating larger convoys. [ABSTRACT FROM AUTHOR]

The issue of safety and free navigation near the Vistula Lagoon for many years was a dispute between Poland and Russia. The most debatable and conflicting topic, especially in Poland, was building a new connection between the Gulf of Gdansk and the Vistula Lagoon. This paper describes the functional processes and mechanisms of the new lock installed at the harbour Nowy Świat and the results of quantitative analysis of traffic changes resulting from that addition (from the beginning of their operations through January 2023). The next part of the work focuses on safety navigation analysis for typical vessels which operate on this newly built waterway. Underkeel clearance analysis and the channel's minimum safety width were carried out, assuming the most common types of ship. The research results provide the foundation for further potential analysis of the Nowy Świat Canal transport possibilities. [ABSTRACT FROM AUTHOR]

The navigational safety of ships on waterways plays a crucial role in ensuring the operational efficiency of ports. Ship anomalous behavior detection is an important method of water traffic surveillance that can effectively identify abnormal ship behavior, such as sudden acceleration or deceleration. In order to detect potential anomalous ship behavior in real time, a method for ship anomalous behavior detection in waterways is proposed based on text similarity and kernel density estimation. Under the assumption of known traffic patterns entering and leaving the port, this method can identify ship behaviors that violate traffic patterns in real time. Firstly, kernel density estimation is applied to construct a traffic pattern density model for ship trajectories entering and leaving the port, used to estimate the density values of ship motion states. Simultaneously, a semantic transformation method is used to convert traffic pattern trajectory into pattern trajectory text, which is used to identify the ship's traffic pattern. Subsequently, the historical trajectory data of the target ship are transformed into textual trajectories, and text similarity is used to identify ship inbound and outbound traffic patterns. Furthermore, the constructed traffic pattern density model is used to estimate real-time density values of the state of ship motion, and the trajectory points that exceed the threshold of the anomaly factor are marked as anomalies. Finally, the effectiveness of the proposed method is validated using simulation data, and the results indicate an accuracy of more than 90% for the comprehensive detection of anomalous behavior. This study, approaching the detection of potential ship anomalous behavior from the perspective of port traffic patterns, enriches the methods of ship anomalous behavior detection in port waterways. [ABSTRACT FROM AUTHOR]

Intelligent navigation is a crucial component of intelligent ships. This study focuses on the situational awareness of intelligent navigation in inland waterways with high vessel traffic densities and increased collision risks, which demand enhanced vessel situational awareness. To address perception data association issues in situational awareness, particularly in scenarios with winding waterways and multiple vessel encounters, a method based on trajectory characteristics is proposed to determine associations between Automatic Identification System (AIS) and radar objects, facilitating the fusion of heterogeneous data. Firstly, trajectory characteristics like speed, direction, turning rate, acceleration, and trajectory similarity were extracted from ship radar and AIS data to construct labeled trajectory datasets. Subsequently, by employing the Support Vector Machine (SVM) model, we accomplished the discernment of associations among the trajectories of vessels collected through AIS and radar, thereby achieving the association of heterogeneous data. Finally, through a series of experiments, including overtaking, encounters, and multi-target scenarios, this research substantiated the method, achieving an F1 score greater than 0.95. Consequently, this study can furnish robust support for the perception of intelligent vessel navigation in inland waterways and the elevation of maritime safety. [ABSTRACT FROM AUTHOR]

The world is more urbanized now than ever before and maintaining some form of amenity from natural or modified ecosystems in the urban context is an increasingly significant challenge. This is not aided by the somewhat amorphous definition of amenity itself. This article introduces a framework for conceptualizing the amenity of urban waterways and provides empirical evidence about the relative weight of the different determinants of waterway amenity. We use best‐worst scaling to examine how households rate the relative importance of the amenity attributes along with data about how households rate their "connection" to waterways. Comparisons of preferences are made across four cities in Australia, all ranked in the top 10 most liveable cities in the World in 2021. The study also captures the relative importance of how "experts" in the field perceive these attributes. We find evidence that public preferences are not always aligned with those of experts and uncover significant heterogeneity within household respondents. To illustrate one way to cater for this heterogeneity in urban planning we report the results of a total unduplicated reach and frequency analysis as a means of identifying an efficacious portfolio of interventions. Accordingly, the study provides useful insights for waterway managers seeking to improve the allocation of resources and generate the most efficient amenity outcomes. Key Points: We introduce a framework for conceptualizing the amenity of urban waterwaysBest‐worst scaling is applied to examine how households and experts rate the relative importance of amenity attributes of urban waterwaysFindings inform waterway managers seeking to improve the allocation of resources and generate the most efficient amenity outcomes [ABSTRACT FROM AUTHOR]

Copyright of Automatisierungstechnik is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ship hydrodynamics in a constant waterway have been well studied. With a coordinate system fixed on the moving ship, the boundary value problem (BVP) is usually treated as a steady one. However, the hydrodynamics of a ship moving in confined waterways with abrupt changes in width or depth are complex due to their unsteady nature. The studies on such unsteady problems are insufficient. In the engineering practice, the hydrodynamic unsteadiness can be fully reflected by a scenario when a ship enters a lock. Prior studies have predominantly focused on predicting the ships' hydrodynamic forces without considering the unsteady terms on the free-surface boundary conditions. Obviously, such steady or quasi-steady methods overlooked the crucial unsteady phenomena on free water surface. To address this gap, the present study introduces a novel three-level difference scheme to discretize the free surface condition, preserving unsteady terms while maintaining temporal continuity of cells on the free surface. With the implementation of such fully unsteady BVP, we observed some interesting unsteady free surface motions, which were not well documented in the existing literature. To verify our new observations, as well as to validate the numerical method proposed in this study, two physical model tests were designed and conducted in a towing tank: a submerged ellipsoid enters a deep lock at relatively high speeds, and a box enters a shallow and narrow lock at very low speeds. The discussion is highlighted on the unsteady waves in front of the moving bodies, as well as the unsteady resistance induced by such waves. [ABSTRACT FROM AUTHOR]

Noticing nature has often been described as a process through which young people come to know, understand, and care for it. This paper challenges these assumptions through examining practices of noticing nature, as together, young people and adults notice environmental features on urban waterways. Drawing on a project that provided opportunities for young people of Somali heritage to access waterways in Leicester, through canoeing, nature- and heritage-based activities, we examine instances of noticing young people recorded on film. Using the techniques of ethnomethodology and conversation analysis, three fragments of film are analysed: Noticing a heron, ducks, and a dead rat. Through these, we explore the intersubjective social production of noticing, how adults seek to structure that developing sense of noticing, and the role of technologies through which young people notice. Considering how young people disrupt adult spatial orderings, we find that adults and young people do not straightforwardly fall into expert and novice categories in terms of reinforcing norms of noticing nature. Instead, adults sometimes reinforce, sometimes dismiss, young people's sense of what and how to notice. We reflect on how the urban waterway as disordered spaces are socially produced through in-the-moment noticings, and how young people and adults might categorise desirable and undesirable nature-to-notice. [ABSTRACT FROM AUTHOR]

This study aims to enhance the safety and efficiency of port navigation by reducing ship collision accidents, minimizing environmental risks, and optimizing waterways to increase port throughput. Initially, a three-dimensional map of the port's waterway, including data on water depth, rocks, and obstacles, is generated through laser radar scanning. Visual perception technology is adopted to process and identify the data for environmental awareness. Single Shot MultiBox Detector (SSD) is utilized to position ships and obstacles, while point cloud data create a comprehensive three-dimensional map. In order to improve the optimal navigation approach of the Rapidly-Exploring Random Tree (RRT), an artificial potential field method is employed. Additionally, the collision prediction model utilizes K-Means clustering to enhance the Faster R-CNN algorithm for predicting the paths of other ships and obstacles. The results indicate that the RRT enhanced by the artificial potential field method reduces the average path length (from 500 to 430 m), average time consumption (from 30 to 22 s), and maximum collision risk (from 15 to 8%). Moreover, the accuracy, recall rate, and F1 score of the K-Means + Faster R-CNN collision prediction model reach 92%, 88%, and 90%, respectively, outperforming other models. Overall, these findings underscore the substantial advantages of the proposed enhanced algorithm in autonomous navigation and collision prediction in port waterways. [ABSTRACT FROM AUTHOR]

Lotic ecosystems are sources of greenhouse gases (GHGs) to the atmosphere, but their emissions are uncertain due to longitudinal GHG heterogeneities associated with point source pollution from anthropogenic activities. In this study, we quantified summer concentrations and fluxes of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and dinitrogen (N2), as well as several water quality parameters along the Rhine River and the Mittelland Canal, two critical inland waterways in Germany. Our main objectives were to compare GHG concentrations and fluxes along the two ecosystems and to determine the main driving factors responsible for their longitudinal GHG heterogeneities. The results indicated that the two ecosystems were sources of GHG fluxes to the atmosphere, with the Mittelland Canal being a hotspot for CH4 and N2O fluxes. We also found significant longitudinal GHG flux discontinuities along the mainstems of both ecosystems, which were mainly driven by divergent drivers. Along the Mittelland Canal, peak CO2 and CH4 fluxes coincided with point pollution sources such as a joining river tributary or the presence of harbors, while harbors and in-situ biogeochemical processes such as methanogenesis and respiration mainly explained CH4 and CO2 hotspots along the Rhine River. In contrast to CO2 and CH4 fluxes, N2O longitudinal trends along the two lotic ecosystems were better predicted by in-situ parameters such as chlorophyll-a concentrations and N2 fluxes. Based on a positive relationship with N2 fluxes, we hypothesized that in-situ denitrification was driving N2O hotspots in the Canal, while a negative relationship with N2 in the Rhine River suggested that coupled biological N2 fixation and nitrification accounted for N2O hotspots. These findings stress the need to include N2 flux estimates in GHG studies, as it can potentially improve our understanding of whether nitrogen is fixed through N2 fixation or lost through denitrification. [ABSTRACT FROM AUTHOR]

The document titled "Applied Maritime Engineering and Transportation Problems 2022" provides an overview of marine traffic engineering (MTE) and its various research areas. It covers the history of MTE, ship maneuver simulation methods, the design of waterways and ports, and the impact of hydrometeorological conditions on ship behavior. The document also discusses topics such as seafarer competence evaluation, ship-maneuvering simulation in restricted waters, and port infrastructure optimization. It emphasizes the interdisciplinary nature of MTE and its importance in ensuring safe, efficient, and sustainable maritime operations. The future of MTE includes advancements in automation, artificial intelligence, cybersecurity, environmentally friendly technologies, and global cooperation for shipping safety. [Extracted from the article]

When an unmanned surface vehicle (USV) navigates in narrow waterway scenarios, its ability to detect vanishing points accurately and quickly is highly important for safeguarding its navigation safety and realizing automated navigation. We propose a novel approach for detecting vanishing points based on an improved lightweight AlexNet. First, a similarity evaluation calculation method based on image texture features is proposed, by which some scenarios are selected from the filtered Google Street Road Dataset (GSRD). These filtered scenarios, together with the USV Inland Dataset (USVID), compose the training dataset, which is manually labeled according to a non-uniformly distributed grid level. Next, the classical AlexNet was adjusted and optimized by constructing sequential connections of four convolutional layers and four pooling layers and incorporating the Inception A and Inception C structures in the first two convolutional layers. During model training, we formulate vanishing point detection as a classification problem using an output layer with 225 discrete possible vanishing point locations. Finally, we compare and analyze the labeled vanishing point with the detected vanishing point. The experimental results show that the accuracy of our method and the state-of-the-art algorithmic vanishing point detector improves, indicating that our improved lightweight AlexNet can be applied in narrow waterway navigation scenarios and can provide a technical reference for autonomous navigation of USVs. [ABSTRACT FROM AUTHOR]

Sorting out the requirements for intelligent functions is the prerequisite and foundation of the top-level design for the development of intelligent ships. In light of the development of inland intelligent ships for 2030, 2035, and 2050, based on the analysis of the division of intelligent ship functional modules by international representative classification societies and relevant research institutions, eight necessary functional modules have been proposed: intelligent navigation, intelligent hull, intelligent engine room, intelligent energy efficiency management, intelligent cargo management, intelligent integration platform, remote control, and autonomous operation. Taking the technical realization of each functional module as the goal, this paper analyzes the status quo and development trend of related intelligent technologies and their feasibility and applicability when applied to each functional module. At the same time, it clarifies the composition of specific functional elements of each functional module, puts forward the stage goals of China's inland intelligent ship development and the specific functional requirements of different modules under each stage, and provides reference for the Chinese government to subsequently formulate the top-level design development planning and implementation path of inland waterway intelligent ships. [ABSTRACT FROM AUTHOR]

The construction and development of international transport corridors have become a means of cross-border space governance, promoting the flexibility of international industrial chains and supply chains. Due to the uncertainty of cooperation, the development of international transport corridors entails a long-term and complex system of engineering. Transport corridors can generate wider economic benefits and costs through their effects on a potentially diverse set of development outcomes, such as economic growth, poverty, jobs, equity, environmental quality, and economic resilience. The focus on roads, rails, and waterways is justified, as transport corridors based on these modes have clearer potential for economic spillovers than, for example, airline routes. The current paper describes a multi-method approach involving spatial and non-spatial analysis to investigate spatial disparity along a proposed corridor and examine its integration within the existing settlement structure. The conceptual structure for the review is guided by a simple canonical model describing the policy maker's problem in maximizing the net wider economic benefits of corridors. The meta-analysis confirms that characteristics of individual studies, as well as the placement and design of transport infrastructures, systematically influence the findings of corridor studies. It also shows that, on average, estimated impacts of corridor interventions on economic welfare and equity tend to be beneficial, while they are often detrimental to environmental quality, and possibly also to social inclusion. [ABSTRACT FROM AUTHOR]

Regulated waterways, interconnected by navigation barriers (locks and dams), are uniquely difficult to manage, given interest in enabling native species connectivity while minimizing invasions. Canada's historic Rideau Canal Waterway, a 202 km navigable route located in eastern Ontario and connected by 24 lockstations, embodies this challenge. The lock(s) and water-control dam that compose each lockstation may respectively offer a connectivity pathway, though to what extent is unclear. We used acoustic telemetry (native largemouth bass (Micropterus nigricans) and northern pike (Esox lucius), and invasive common carp (Cyprinus carpio); n = 224) to evaluate fish connectivity relative to lock operations and environmental data over three years (2019–2021). Thirty-five passages by 23 native fishes were recorded, with 49% of passages through locks. No common carp passages were detected; movements indicate that they favour higher flow areas downstream of dams, regions with no pathway upstream. Most passages were downstream and, of concern to obligate upstream migrators, we found that multi-flight and higher-lift locks appear impassable to upstream movements. Our results suggest that these lockstations limit, but not entirely restrict, connectivity. [ABSTRACT FROM AUTHOR]

Microbial monitoring in marine recreational waterways often overlooks environmental variables associated with pathogen occurrence. This study employs a predictive boosted regression trees (BRT) model to predict Staphylococcus aureus abundance in the Tampa Bay estuary and identify related environmental variables associated with the microbial pathogen's occurrence. We provide evidence that the BRT model's adaptability and ability to capture complex interactions among predictors make it invaluable for research on microbial indicator research. Over 18 months, water samples from 7 recreational sites underwent microbial quantitation and S. aureus isolation, followed by genetic validation. BRT analysis of S. aureus occurrence and environmental variables revealed month, precipitation, salinity, site, temperature, and year as relevant predictors. In addition, the BRT model accurately predicted S. aureus occurrence, setting a precedent for pathogen–environment research. The approach described here is novel and informs proactive management strategies and community health initiatives in marine recreational waterways. [ABSTRACT FROM AUTHOR]

Riparian areas can be highly biodiverse and provide critical ecosystem services. However, they are frequently subject to anthropogenic impacts such as land clearing, agricultural use, and urban development. Restoration of riparian areas via revegetation commonly improves the health of waterways and surrounding areas, but vegetation outcomes are rarely assessed. Our study compared 10 to 14‐year‐old revegetation to remnant vegetation in riparian areas of south‐eastern Australia to determine if species composition, vegetation structure, and ecosystem function (plant recruitment) differed. We also assessed if the amount of surrounding native vegetation, browsers (including deer, rabbits, and macropods), or soil characteristics influenced native woody plant recruitment at revegetated sites. While native and exotic woody species richness did not differ, native woody plants were less abundant and exotic woody plants twice as abundant at revegetated sites. The ground layer of revegetated sites was dominated by weeds, whereas remnant sites largely comprised native herbaceous plants and leaf litter. Tree heights and tree canopy cover were similar in revegetated and remnant areas, although shrubs and ferns were lacking in revegetation. Native woody plant recruitment was lower at revegetated sites and was negatively associated with browser presence. Our results suggest that while revegetation may have similar species richness and tree cover as remnant areas, weeds often dominate and important structural components such as shrubs and ferns, and ecological processes such as plant recruitment, are lacking. Better consideration of all vegetation strata, reduced browsing pressure and weed control are likely to achieve better revegetation outcomes. [ABSTRACT FROM AUTHOR]

This study examines the impact of urban waterway conditions on property market prices. In general, similar revealed preference studies typically focus on identifying the value associated with changes in attributes such as riparian vegetation or water quality. Using an index that classifies waterways based on the vegetation and channel conditions, we analyse both attributes. Our spatial hedonic property price model findings indicate that buyers are willing to pay premiums ranging from 2.7% to 8.5%, depending on vegetation and channel conditions. However, when the proximity to the waterway is accounted for, we found that properties adjacent to the highest‐ranked vegetation and channel conditions attract a higher premium of 12.8%. Overall, the implicit marginal effects for the distance–condition interaction variables indicate that for lower‐ranked waterway conditions, there is a relative aversion to being adjacent to waterways. The results suggest that there are significant gains to be realised from removing concrete‐lined channels and replacing them with stones for banks, or re‐creating unmodified channels, even if there is only limited scope for increasing vegetation. [ABSTRACT FROM AUTHOR]

Apocorophium lacustre – a species of benthic amphipod native to American and European estuaries along the North Atlantic Ocean – has rapidly expanded outside of its native range and is now established in the Illinois, Upper Mississippi, and Ohio river systems, USA. A. lacustre is considered high risk for colonization and disruption of the Laurentian Great Lakes’ benthic communities. To further our understanding of factors influencing A. lacustre distribution and its threat to the Great Lakes, zoobenthic and habitat data were collected from colonization samplers (i.e., rock bags) deployed at 370 sites along the Illinois Waterway. A. lacustre was found in the lower six pools of the Illinois Waterway and was the most abundant amphipod collected in those pools. Our results parallel other studies in that A. lacustre was not observed upstream of Dresden Island Pool, but A. lacustre was found ~11 km farther upstream of any previous records. Generalized linear mixed effects modeling indicated that parameters pertaining to food availability, water quality, and impoundment influenced A. lacustre abundance. Model averaging identified five statistically significant variables: A. lacustre abundance was negatively associated with turbidity, fluorescent dissolved organic matter, and vegetation density and positively associated with temperature and downstream distance (i.e., closer to the next downstream dam). Our findings of what factors influence A. lacustre abundance should be of broad interest to risk assessment and invasion forecasting in other regions where A. lacustre have been or may be introduced. [ABSTRACT FROM AUTHOR]

This paper continues the analysis of the management of urban waterways in Greater Melbourne, Australia, commenced with our first paper. We focus first on the increasing emphasis on waterways and their corridors as part of Melbourne's liveability, and then on the future management of waterways and their corridors in the face of the three most pressing future challenges – climate change, population increase, and urban expansion and densification. The long history of the development of parks, gardens and open spaces in Melbourne is reviewed. These open-spaces initially occurred with quite strong linkage to the waterways, enabled by the city's unique institutional arrangements, but were substantially weakened as a result of policy and governance reforms in the 1990s. Melbourne will need to substantially improve the integration of the management of urban waterways and their corridors with the planning, development and management of the city's associated green spaces if it is to achieve the expected community liveability standards in the face of the above three future challenges. Additionally, if waterway management remains with the existing agency (Melbourne Water), the authorising environment and the culture and mindset of this agency will need to change its focus from the current 'city servicing' institutional model to a 'city shaping' model. [ABSTRACT FROM AUTHOR]

The geometric design of a waterway embankment depends on several factors like soil and subsoil properties, loading conditions, geometric constraints, climate & weather conditions, etc. Surface wind velocity (V) and fetch length (F) are two control factors that help to determine the wave height (H) utilizing the Taguchi Factorial design method. A non-linear equation was generated by integrating optimized H with the upstream water pressure (P). In the JAVA environment, a pseudo-code was created to solve the non-linear equation and determine the resulting hydrostatic height (hw) and crest width (b). The calculated hw and b were validated utilizing the Honey-Badger algorithm by initializing all the control factors along with P. The outcomes from the experimental analysis of Taguchi showcase that lower control factors helped to obtain the maximum hw along with b for the embankment. As per Analysis of Variance (ANOVA), maximum V was found to be the most significant control factor influencing the determination of H, hw and b of the earthen embankment. The regression squared (R²) value from the Design of Experiment (DoE) of the Taguchi method was found to be 99.21% which shows that the observed data were well fitted to the developed model for evaluating the contribution of Signal to Noise (S/N) ratio and verify the validity of optimal factor settings through confirmation experiments. The confirmatory test was piloted to check the similarity index between the two methods and the outcomes were found to be nearly similar with an error of 2.62%. [ABSTRACT FROM AUTHOR]

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