bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study on Navigation Flow Condition of Downstream Approach Channel of Navigation Facilities of Baise Water Conservancy Project
Authors: Yu Kaiwen , Han Changhai , Han Kang , Zhao Jianjun , Yu Zhiguang
Published: February 2023

Baise Water Conservancy Project is the second cascade in the Yujiang River planning, and its navigation facilities are one of the key projects to get through Yunnan and Guizhou. The exit of the downstream approach channel of the navigation facilities of the Baise Water Conservancy Project is located about 700 m downstream of the Dongsun Hydropower Station, so the operation of Dongsun Hydropower Station has a direct impact on the navigation flow condition of the approach channel. In addition, the topography of the river also has an obvious influence on the navigation conditions at the entrance area of the approach channel. So, based on the overall hydraulic model with a scale of 1:80 and the self-navigating ship simulation test, the navigation flow conditions at the entrance area of the approach channel and the characteristics of the ship entering and exiting the ship lock were studied. The test results show that: (1) Under the condition that the discharge of Dongsun Hydropower Station is less than1500 m3/s at full power, the flow pattern in the downstream channel of the hydropower station and the entrance area of the approach channel is relatively smooth. The flow pattern, velocity and wave height can meet the specification requirements. The maximum rudder angle and drift angle at the entrance area of the approach channel do not exceed the requirements, and the ship can enter and exit the downstream approach channel smoothly; (2) The maximum navigation discharge of 1700 m3/s can be achieved by adjusting the route of the connecting section of the downstream approach channel to the left bank and dredging the two convex points on the right bank of the entrance area of the downstream approach channel.
Flow and Sedimentation Characteristics of Tidal Waterways – with the Kouanzhi Waterway in the Lower Yangtze River as an Example
Authors: Qin Jie , Jing Ye , Lei Xueting , Wu Teng , Agbemafle Elikplim
Published: February 2023

River flow in the Lower Yangtze River (LYR) is influenced by the combined effect of runoff and tides, and the complex flow conditions tend to cause sediment deposition in waterways, which in turn affects navigation conditions. In order to improve the understanding of the river mechanism of tidal reaches, this study selected a typical reach in the LYR – the Kouanzhi Waterway (KW) – as an example to investigate the flow characteristics that affect sediment transport processes. Sedimentation annually occurs at the entrance of the KW and a large sidebar constantly increases in size, causing the reduction of navigation depth and width, but the causes of the sedimentation are still unclear. In this study, a three-dimensional (3D) model of the KW was established based on the Delft3D, and the k-epsilon model was chosen to simulate the turbulent flow. The model simulates the flow processes during flood tides in flood and dry seasons. The results of the numerical simulation show that a significant difference exists in the large-scale flow structures between the flood and the dry seasons. In the flood season, flow at the entrance of the KW is extremely turbulent and a large-scale vortex shedding phenomenon is formed downstream of the channel entrance, which causes a great sediment transport rate at the entrance. In addition, because the river width widens in the middle part of the KW, a large-scale circulation flow structure is developed near the Sanyiqiao sidebar. The circulation is supposed to trap and deposit sediment on the sidebar. In the dry season, the intensity of flow turbulence is greatly reduced, which causes the sediment transport rate at the entrance decreases accordingly. In addition, the circulation flow structure at the Sanyiqiao disappeared, and thus the sidebar is supposed to be under erosion during this period. The results of this study provide a vital reference for the engineering works of waterway regulations in tidal river reaches.
Research on the Non-constant Navigable Water Flow Conditions of the River Channel Downstream of the Navigable Facilities of Baise Water Control Project
Authors: Guan Mingfang , Zhang Ming , Han Changhai , Qing Leng , Hang Yu
Published: February 2023

The exit of Baise ship lift on the Right River is only about 700 m away from Dongsun Hydropower Station. Its dispatching operation, especially the unsteady flow, has a direct impact on the navigable water flow conditions of the approach channel gate area and river channel downstream of the Baise ship lift. According to some characteristics of Baise Junction and Dongsun Junction and the measured topography of Baoai River, a plane two-dimensional numerical model of the research river section is constructed, and the water flow changes in the mouth area under different working conditions are simulated and calculated. The research results show that the safety of navigation in the entrance area can be guaranteed from two aspects: optimizing the operation mode of the Baise and Dongsun cascade hydropower stations, and rationally formulating the downstream ship navigation management mode. Under the operating conditions of the four units of Baise Power Station, it is recommended that the ship wait for 0.5 h after the two units in Dongsun are started, so as to avoid the maximum water level increase period in the first half hour.
Three-Dimensional Hydrodynamic Analysis and Early Warning of Ω-Collapse in the Lower Reaches of the Yangtze River Based on Experimental Study on Generalized Model
Authors: Jia Menghao , Zhang Fanyi , Lyu Xinyi , Wen Yuncheng , Xu Hua
Published: February 2023

Under the background of the construction of cascade reservoir group in the main stream of the Yangtze River, the lower reaches of the Yangtze River are faced with new water and sediment situation, which leads to the increased risk of bank collapse in the lower reaches of the Yangtze River. Therefore, the purpose of this study is to have a certain supporting significance for the prevention and control of riverbank collapse disasters. The study takes the Jiangsu section of the lower reaches of the Yangtze River as the research object. Firstly, according to the measured data over the years, the macroscopic characteristics of the collapsed bank in the Jiangsu section are analyzed, and the temporal and spatial distribution characteristics are mainly analyzed. The research results show that the collapse of the Jiangsu section of the Yangtze River is dominated by Ω-collapse, which mostly occurs in the flood season and the post-flood receding water period. The frequency of bank collapse in the Yangzhong Reach is relatively the highest among all river segments, and there are more bank collapses on the north bank than the south bank. According to statistics, the average collapse width of the collapse in the Jiangsu section can reach 130 m, the depth of the collapse can reach 60 m, and the ratio of the average bank collapse to the depth can reach 2.15. Then, aiming at the characteristics of the main bank collapse type in the Jiangsu section is the Ω-collapse, the experimental investigation and numerical calculation are used to conduct in-depth research, combined with the measured data, probability and statistical analysis and theoretical analysis. Three-dimensional hydrodynamic analysis is carried out on the mainstream area near the collapse area and outside the collapse area, focusing on the analysis of its nearshore velocity and shear stress and other factors. Combined with the water tank test, the water flow in the inner surface, middle and bottom layers of the Ω-type nest was studied under different flow levels, and it was concluded that the water flow in the nest had a counterclockwise backflow, and the backflow intensity gradually weakened from the side wall to the center. And the phenomenon that the surface layer and the bottom water flow are separated, and this phenomenon becomes more prominent with the increase of the flow rate.
Shipper Response Surveys and their Importance in the Evaluation of U.S. Inland Waterways
Authors: Knight Kevin P.
Published: February 2023

Shipper response surveys have been growing in favor in recent years and if administered correctly, can help quantify shipper’s behaviors and opinions which present themselves as transportation demand functions by mode of delivery (water, rail or truck). Demand functions, defined by economists as “numeric demand elasticities” or changes in quantity demanded as a result of changes in rates/duration/reliability, have enabled to the Corps to analyze (1) lock reliability and component failures; (2) demand projections vs. system capacity to determine equilibrium waterway traffic and (3) selection and sequence of replacement, repair or modernization efforts over the planning horizon.

This paper highlights this innovative approach in predicting shipper behavior using shipper response surveys that were recently applied to two major waterways in the U.S.– the Upper Mississippi River and Ohio Rivers) and how the resulting outputs could be used in to analyze lock investment priorities as well as impacts due to closures and other events.
Solar Parks and Wind Farms Along Inland Waterways – Mitigating Measures Concerning Hindrance for Vessel Traffic
Authors: Koedijk Otto C.
Published: February 2023

In the search for space for producing renewable energy, possible negative effects of solar parks and wind farms along inland waterways can easily be overseen. This paper provides an exploratory description of effects for navigation like blinding of helmsmen, disturbance of radio communication and exaggeration of vessel’s radar images and concludes with a chapter on mitigating measures.
Development of Inland Shipping and Construction of New Three-Gorges Ship Channel
Authors: Niu Xinqiang , Wu Jundong , Wang Yachao , Wang Xiaowei , Zhou Hao , Zheng Yu
Published: February 2023

Inland waterways in China flows from west to east, affects the economy of South and North China, communicates with the ocean.
Sustainable Management of the Navigability of Natural Rivers (PIANC WG 236)
Authors: Creech Calvin , Mosselman Erik , Hiver Jean-Michel , Huber Nils
Published: February 2023

The PIANC InCom/EnviCom Working Group 236 was established in early 2021 to develop PIANC guidelines for improving navigability conditions on natural or quasi-natural rivers, while maintaining morphological processes and natural river form and function. Its key objectives include: 1) development of guidelines to improve and maintain the navigability in natural rivers; 2) assess the sustainability of river training works designed to improve the navigability; 3) assess the sustainability of dynamic river management (monitoring and shifting of navigation aids to adapt the navigation channel to the river dynamics); 4) highlight the technical, operational, economic and environmental considerations for navigation in natural rivers compared to that in regulated rivers and canals; and 5) improve the understanding of the physical processes in natural rivers, developed with or without river training works. The developed guidance includes a planning framework for developing a navigability improvement masterplan for a natural or quasi-natural river system, and the integrated and adaptive management strategies that can be applied at a system scale. Specific interventions and measures have been identified to meet the dual goals of maintaining morphological river function and improving navigability conditions. These measures include dynamic charting; morphological dredging and disposal management; Temporary, Adaptable, and Flexible Training Structures (TAFTS); riverbed armoring and sediment nourishment; rock excavation; meander cutoffs and oxbow development; localized traditional river training structures; and channel closure structures. The impacts and strategies for mitigation associated with some of the measures are analyzed and discussed. Finally, the continual monitoring, management, and operational tools available for improving navigability in a morphologically active river system is presented. It is recognized that natural and quasi-natural rivers will typically be more fluvially active and dynamic than systems that have used traditional methods for navigability improvements including heavily trained rivers or systems with locks and dams. These unrestricted and unconfined river systems, therefore, will require new and innovative strategies to monitor the fluvial and geomorphic changes of the system in order to inform managers and navigators of the river. Case studies are presented that include the Madeira River (Brazil); Magdalena River (Colombia); Niger Delta (Nigeria); Yangtze River (China); the Brahmaputra-Jamuna River (India); and the Red River (Vietnam).
The Navigable Frontier Canal of the African Rift
Authors: Deplaix J. M.
Published: February 2023

This Multipurpose Canal is one of the biggest infrastructure projects for Africa in the 21st Century. It aims at linking 3 river basins, Nile, Congo, and Zambezi. It will eventually connect all the Great Lakes of the African Rift: Albert, Edward, Kivu, Tanganyika and Malawi, as well as Victoria.

It is Multipurpose, as it will involve Hydropower, Navigation, as well as Security and Peace aspects.

Here, are described only Navigation aspects.

This project presents many challenges to the designer, mostly because of the huge difference of elevation between the lakes, and of the divides to climb, reaching up to 2 000 m between the Nile and Congo basins.

The Report presents the design criteria, as well as tentative alignments, possible canalisation steps and techniques to be used over this route, in particular Waterslope, Blue Wave and Pulsating canalisation.

This project is promoted by CSP-REGLA, a Congolese NGO. The first step, Integrated Development of Semliki River, is being studied by the Ministry of Regional Integration of DRC. More details are given about this particular project.
Analysis on Throughput Capacity of Water-Saving Ship Lock in Simulation Method
Authors: Tang Ying , Liu Chunze , Cao Fengshuai , Shang Jianping
Published: February 2023

When the double-line water-saving ship locks operate in the mode of filling and emptying mutually, the filling water process of one lock chamber and emptying water process of the other one are carried out at the same time, thus the situation of chambers waiting for each other is inevitable. Besides, the variation of ship navigating speed and safety interval time between two adjacent ships may have a more significant impact on the operation efficiency of the ship lock, which cannot be ignored. Combined with the actual condition of a planned lock on a canal in China, the throughput capacity and operation efficiency of the double-line water-saving ship locks under the mode of filling and emptying mutually are studied. A coupled operation simulation model of double-line locks is established, in which the mode of filling and emptying water mutually or independently is adopted. In the model, the whole operation processes of the locks are simulated. The simulation results show that the throughput capacity of the planned ship lock is reduced by 5.6%–7.8%, and the average lockage time is increased by about 10.8%, when comparing the mode of filling and emptying water mutually with independently. Besides, using average value of speed and safety interval time of ships is acceptable when doing research on the throughput capacity and operation efficiency of ship locks. The achievements can provide technical support for the analysis of the throughput capacity and operation efficiency of the water-saving ship lock.
Benchmark of Turning Basin Options for the ECMT Class V Network of Nord-Pas-de-Calais (France)
Authors: Page Sebastien , Mansuy Marc , Eloot Katrien , Candries Maxim , Adams Roeland
Published: February 2023

The Nord-Pas-de-Calais Division of Voies navigables de France (VNF), the French Waterways authority, is preparing a master plan for the development of turning basins for its ECMT class V network. In this frame, IMDC has been asked to carry out a comparative analysis (benchmark) of the different designs of turning basins in France and elsewhere in the world and to propose design criteria adapted for future developments (for ships of 110 m and 135 m) on the Nord-Pas-de-Calais network. The first part of the study consisted in a desktop review of available national and international guidelines or recommendations on the subject of turning basins design. This helped building a better understanding of the needs in terms of geometry for safe and/or comfortable turning maneuvers. Technical studies of built or projected turning basins on the Nord-Pas-de-Calais network were also analyzed to refine the knowledge on local conditions. Based on the findings of the desktop analysis, interviews of European waterways authorities, international experts and skippers were carried out to further improve the understanding of the problem, both from the infrastructure side as well as from the users’ side. On top of geometry concerns, the interviews tackled hydrometeorological constraints, operational and environmental aspects, auxiliary equipment, etc. From this, a draft technical reference system was proposed for future turning basins on the Nord-Pas-de-Calais network. It proposes two options, depending on whether the basin is located on two banks or on one bank only, and aims at offering each option in two safety and ease levels: a comfort level version, on which the turn must always be relatively easy, and a safety level version, on which the turn must always be possible, but with less ease. The designs were then tested using real time navigation simulations. Optimizations of some of the designs were also proposed to adapt to severe hydro-meteorological conditions. Finally, a decision tree has been developed to facilitate the selection of a design solution according to the local characteristics of the projected basin location on the network. This tool allows the selection of the geometry allowing the easiest turn possible according to the available space and the hydrometeorological conditions present on the envisaged site.
Development of a Port Facility Diagnostic System that Utilizes Data Measured by Strong Motion Seismographs
Authors: Matsunaga Hiroaki , Kyouda Junichi , Itakura Sou , Yamamoto Tatsuru , Sone Akito , Kadono Takashi
Published: February 2023

The Authors developed a damage assessment system for mooring facilities. This system uses information on seismic motion observed by strong motion seismographs when an earthquake occurs in order to determine whether or not mooring facilities can be used based on the degree of damage suffered. The system creates maps estimating damage based on the results. Two methods are available for determining usability—immediate diagnoses and detailed diagnoses—and all calculations are performed automatically, from the acquisition of the seismic motion information to the determination of usability. The resulting maps estimating damage can be used to select surveyed facilities for on-site damage assessments, making this system an effective tool for supporting initial response systems after a disaster strikes.
Effect of River Regulation on Navigable Flow Conditions for River Bend
Authors: Fan Honghao , Zhao Jianjun , Ye Jianguo , Chen Xianzhong , Fang Jintao , Wang Yu , Zheng Xingwei
Published: February 2023

The layout of the navigable junction on the curved river was relatively difficult. The combination of the curved flow and the oblique flow would increase lateral flow velocity in the entrance area, which affected the navigable safety of the ship. There was a bend in the entrance area of the Zhaoxian Junction downstream and a large area of flood plain on the right bank of the downstream channel, which contributed to hardly meet the navigation requirements due to flow coming straight towards waterway affected by flood plain squeezed and river bend. In this paper, normality hydraulic model with 1/80 scale was employed to experimentally optimize the influence of different river regulation measures on navigable flow conditions considering the characteristics of river bend and another situation. The effective river regulation measures were proposed by moving sluice to the left, dredging flood plain on the right bank of sluice downstream and adjusting the operation mode of sluice gate. It was verified that dredging the downstream flood plain to 65 m elevation combined with the operation of left sluice can meet navigable flow conditions requirements. The research results could be used as a reference for relevant junction projects.
Experimental Study on the Relationship Between the Height of Submerged Dam at the Entrance of Pit-Type Pool and the Treatment Effect
Authors: Ying Qiang , Zhang Xinnong , Jia Dongdong , Chen Changying
Published: February 2023

The submerged dam is one of the commonly used schemes for the prevention and treatment of the pit-type collapse, which is often used in the pit-type collapse emergency treatment in Anhui and Jiangsu sections of the Yangtze River and has achieved good silt-promoting effects. However, the height of submerged dam lacks theoretical and experimental basis in the design and has been determined by experience in the past. Through the physical model of the pit-type collapse of Guizhou Village in the Yangzhong Reach, five different heights of the submerged dam were tested, and the flow velocity, flow direction and surface flow pattern of 12 points in the pond were measured. The test results show that the surface velocity of the inner surface of the submerged dam in the lower part of the pond increases due to the influence of the submerged dam, while the velocity of the bottom layer decreases, and the velocity of the inner side of the upper part mainly decreases; the average velocity in the pond decreases with the increase of the height of the submerged dam and there is a linear relationship between the two; considering that the engineering volume of the submerged dam has a square relationship with the height of the submerged dam, it is believed that the submerged dam should not be too high as long as it meet the sedimentation in the pond.
Innovations in Shiplift Navigation Concepts
Authors: Hu Yaan , Zhao Gensheng , Kunz Claus , Li Zhonghua , Akkermann Jan , Michaux Marc , Daly Fabrice , Stirling Jim , Zheng Weili , Hiver Jean-Michel , Thorogood Michael , An Jianfeng , Wang Xin , Xue Shu , Guo Chao
Published: February 2023

Shiplifts are one of the main types of navigation structures in canals and high dams in natural rivers.
Numerical Investigation of an Inland 64 TEU Container Vessel in Restricted Waters
Authors: Kan Jinyu , Wang Lizheng , Liu Jialun , Wang Xuming , Han Bing
Published: February 2023

Compared with sea-going ships, inland vessels mostly sail in restricted waters, which may cause resistance and ship motions to change greatly. To ensure the safety of navigation, it is of great importance to study the hydrodynamic performance of inland vessels navigating in restricted waters. A 64 Twenty-feet Equivalent Unit (TEU) container vessel is numerically simulated at different speeds and water depth draft ratios (water depth/draft = 2, 2.5, 3, 4, 5, 16). The numerical methods are firstly verified and then applied to systematic simulations. The resistance components, ship motions, and details of flow fields are calculated and analyzed. Generally, the total, frictional and residual resistance coefficients increase with a decrease of water depth as expected. However, at relatively low speeds (Fr = 0.1129 and 0.1135) of h/T = 2, 2.5, 3, the resistance components change conversely that they decrease as the water depth gets shallower. This special phenomenon may be caused by the design of the ship hull or the use of the turbulence model that may not be appropriate. The residual resistance has the same trend as the total resistance and the lines are nearly parallel, which shows that the residual resistance is dominant in the component of total resistance. The ship squat phenomenon happens but is not severe in the shallowest condition (h/T = 2). With the water depth decreasing, the wave amplitude becomes larger and the wave crests near the ship bow and stern also increase, while the troughs change slightly at different water depths.
A New Era for River Information Services (Wg125)
Authors: Creemers Piet
Published: February 2023

Inland Navigation and River Information Services (RIS) are facing in the coming decade many new challenges from various perspectives. All different transport modes are making the shift towards digitalization. Inland navigation is also moving towards a digital world under impulse of different worldwide initiatives. This means data and information services will become more and more crucial and critical for transport and traffic management in inland waterway transport (IWT).
EURIS (European River Information Services System) – The Central European RIS Platform
Authors: Zwicklhuber Thomas , Kaufmann Mario
Published: February 2023

The development and implementation of the River Information Services (RIS) concept started in the end 1990s with various research projects followed by national or regional implementation projects in the first decade of this century. The resulting national RIS systems haven’t been able to exploit the full potential of RIS when it comes to cross-border data exchange and interoperability. To overcome these gaps the concept of RIS Corridor Management was established aiming at linking the fragmented services together on a corridor to supply RIS along the complete route or network. The concept of RIS Corridor Management was taken up by the CEF (Connecting Europe Facility Programme) co-funded multi-beneficiary project RIS COMEX (www.riscomex.eu) with the goal to implement harmonized RIS services on European level. Within the RIS COMEX project the consortium of 13 countries realized a common and centralized single access point to Inland Waterway Information, the European River Information Services (EuRIS) System. EuRIS acts as European RIS platform fulfilling a great variety of information needs of inland waterway stakeholders like skippers, vessel and infrastructure operators, logistics and authorities. The system gathers relevant RIS information from the national systems in order to provide optimized fairway-, infrastructure- and traffic-related services in a single point of access for the users enabling reliable route- and voyage planning and sharing as well as traffic- and transport management on pan-European level. EuRIS provides access to its services via a user-friendly Graphical User Interface (GUI) or machine-readable Open Application Programming Interfaces (API).

In order to guarantee sustainable operation of EuRIS a legal, organizational and financial framework has been setup by the partners. The core aspects concern the joint governance of the system operation as well as the legal basis for RIS data exchange and usage. The full operation and further development of EuRIS is a major milestone in the sector enhancing attractiveness and competitiveness of Inland Waterway Transport in Europe and setting the basis for connectivity to other transport modes and synchro modal logistic operations.
Review of the Key Technology Research on Intelligent Locks
Authors: Xiang Maoming , Hu Yaan , Wang Xiaodong
Published: February 2023

Owing to the high capacity, low costs, and environment-friendly characteristics, shipping has an important role in the sustainable development of the economy, society, and environment. However, with the development of the water transportation economy, the capacity of many navigation locks, such as the Three Gorges ship lock and the Beijing-Hangzhou Canal ship lock, has been hard to meet the increasing demand for passing through the locks. Thus, they have become the “bottleneck” limiting the navigation of the waterways. In the background of the vigorous development of intelligent transportation, the Intelligent Locks has been promoted through extensive research of the Intelligent Locks model, exclusive technology, and intelligent equipment, which is of great significance to improve the efficiency of vessels passing through the locks and enhance the function of waterways. This review starts from the current situation of the research on Intelligent Locks. We summarize the focus of the research on Intelligent Locks and the main tasks of Intelligent Locks. Moreover, the contents of Intelligent Locks are also introduced, such as the network communication platform, intelligent ship identification, positioning system, safety detection system, an intelligent guidance system for shipping, etc. Finally, we conclude that it is the informatization and intelligence that can improve the navigation ability and the management level of ship locks. At the same time, compared with the huge capital demand and the long-period construction of new ship locks, it will have obvious advantages of capital and time by attaching great importance to the automation, informatization, intelligent constructions, and applications of new technologies of existing ship locks.
Status of Research and Application Cases in Intelligent Shipping
Authors: Xu Jiayi , Li Zixiang , Sha Haifei , Wu Shiqiang
Published: February 2023

With the rapid development of information technology, the shipping industry is also experiencing an important period of change in the development of transition to intelligence and wisdom. Intelligent shipping is a service system that promotes inter-departmental cooperation, cross-regional information resource integration, transportation efficiency improvement and transportation cost reduction by using cloud computing, big data, Internet of Things, sensors and other technologies as a comprehensive application with the construction of big data center as a pioneer. Intelligent shipping is the innovative application of relevant advanced concepts and high technology in the shipping industry arising from the construction of intelligent society, however, the development of intelligent shipping is still in the primary stage, and relevant literature on the field of intelligent shipping is still lacking. In order to understand and develop intelligent shipping, this paper reviewed and summarized intelligent shipping based on the existing literature. This paper mainly introduced the background, connotation and development status of intelligent shipping at home and abroad, summarized the framework system of intelligent shipping from five aspects: intelligent ship, intelligent port, intelligent shipping insurance, intelligent supervision and intelligent service, summarized several key technologies in intelligent shipping, and gave examples of successful applications of intelligent shipping at home and abroad. Combined with the current research status of intelligent shipping, this paper put forward the shortcomings and challenges of intelligent shipping, and looks forward to the future development and research direction of intelligent shipping.
Study on Advanced Water Level Simulation Method for Inland Waterway Transport Based on the Extended Manning Formula
Authors: Zhou Junwei , Ma Dianguang , Duan Yu , Ji Chao
Published: February 2023

The water level is a critical hydraulic parameter for inland ship safe navigation, as well as an important variable in inland waterway transport minoring and assistant systems. As a basic and traditional method, the one-dimensional (1D) hydrodynamic model is adapted to simulate river sections/waterway segments to obtain water levels numerically. However, the friction factor, i.e., Manning’s coefficient n, is a sensitive parameter for the traditional 1D hydrodynamic model. Its calibration or identification is not only very time-consuming but also unpractical. Due to its sensitivity to the simulation results, usually, one identified parameter cannot be adopted into other flow scenarios. It has been concluded that the unfitness of the traditional empirical quasi-steady friction formulae leads to these consequences/phenomena. Besides finding advanced parameter calibration algorithms and updating friction parameters dynamically, employing a true unsteady friction formula to replace the quasi-steady friction formula is a thorough solution to the problem. In this study, we introduced a newly proposed 1D unsteady friction formula to the momentum equation of the Saint-Venant Equations, thus a modified 1D hydrodynamic model was developed. To validate its capability in simulating water levels, the modified model was adopted into the Xia-la-xian – La-he-lian section of Daying River; and compared with the traditional model with the Manning formula. Results showed that the modified hydrodynamic model performs better in both water level and cross-sectional average velocity simulation. The research results can be used to support the construction of intelligent water level warning systems, intelligent shipping, and digital waterway transportation platforms.
The Fairway to Corridor Management
Authors: Gilissen Jan
Published: February 2023

This document is a description on the path we’re working on in Flanders to implement corridor management. At this moment we’re already providing services on European lever, but in other to be futureproof inland waterway transport has to take a next step to evolve to a reliable, modern, efficient and innovative transport mode. A brief description is given on the status today and the next phases in the program. Both the waterway authorities and the sector will have to do some efforts to realize the next phases. The document doesn’t consists all the details because this is a work in process with all involved parties.
Field Observation and Experimental Study on the Interaction Between Ship Waves And Vertical Wave Dissipation Revetment
Authors: Ju Liehong , Huang Jingxin , Pan Junning
Published: February 2023

With China’s economic development, many inland waterways adopt vertical revetment structure to save land resources, but this structure is not conducive to wave attenuation. According to the measurement results of the ship wave data of typical ship types in Sunan Canal sailing at different speeds collected in field observation, the maximum wave height in front of the vertical revetment wall was less than 1.0 m under normal navigation conditions, while the navigation administration boats can form a wave height of nearly 1.8 m in front of the vertical revetment wall at the maximum speed. In channels with heavy freight and fast ship speed, the ship waves formed by ships, superposed with the reflected waves by vertical impervious revetment, would result in severe water surface fluctuation, affecting the safety of ship navigation and the stability of revetment structure. Based on the regulation project of Sunan Canal, this paper put forward two types of vertical wave dissipation revetment, namely round-hole caisson structure and grid-type structure. And their wave dissipation effects are compared and optimized through 2-D wave test. Finally, the 3-D physical model tests of ship wave and revetment were carried out, and the effects of reducing ship wave height of round-hole caisson structure and grid structure are compared. The results show that these two vertical wave dissipation structures can reduce the maximum ship wave height in front of the revetment wall by about 20–25%. The relevant research results of this paper can serve as a reference for similar projects.
Analysis of River Stability in the Middle Reaches of Huaihe River Based on Non-equilibrium Thermodynamicsins
Authors: Duan Yu , Xu Guobin
Published: February 2023

River stability is an important attribute of a river, which includes river pattern stability and river bed stability. The stability of the middle reaches of Huaihe River is one of the important problems concerned by the workers in Huaihe River regulation. The study of the stability of the middle reaches of Huaihe River is of great significance to the river regulation planning and flood prevention and control. To explore the stability of the middle reaches of Huaihe River, the research combined with hydrological data, trying to base on the theory of non-equilibrium thermodynamics system to determine the stability of river pattern, and using the unit stream power calculation formula to analyze the river stability. The research show that, the middle reaches of Huaihe River from Zhengyangguan to Fushan, the river pattern of each section is in a stable state, there is no possibility of conversion in the short time. The variation amplitude of unit stream power in each reach tends to decrease, the natural evolution of the riverbed is also in a stable state. Through the research, the applicability of the river stability analysis method based on the non-equilibrium thermodynamics theory in the Huaihe River is verified, and formed a set of analysis methods suitable for the stability judgment and development evolution trend of the Huaihe River. In this study, the stability of the middle reaches of the Huaihe River was judged theoretically, and the adjustment direction of the river and the evolution trend of the river bed were predicted.
An Integrated Approach to Define Estuarine System Resilience, Applied to the Upper Sea Scheldt, Flanders, Belgium
Authors: Adams R. , van Holland G. , Vansteenkiste J. , van Rompaey M. , de Beukelaer-Dossche M. , Bosmans S.
Published: February 2023

The Upper Sea Scheldt (Flanders, Belgium) is a part of the Scheldt estuary which extends from the North-Sea in the Netherlands to the shipping locks in Ghent with a total length of 160 km. Challenges on flood protection and nature development in this unique fresh water estuarine system are addressed in the Sigma-plan. Cumulative effects of i) the autonomous morphological development of the estuary, ii) the further evolution as a consequence of past realignments and dredging works, and iii) sea level rise, result in an increase of tidal dynamics and turbidity which affect both habitat and light climate, and finally disrupt the ecosystem functions.

In order to better understand the system functioning and to prepare for counteracting these undesired evolutions De Vlaamse Waterweg, the waterway manager, has launched a study programme to investigate solutions and to prepare a vision for the future management of the river. An extensive modelling instrument was developed coupling different state of the art modules into one model chain. The developed instrument proved to be highly effective to study (i) the interdependencies between the different river functions which allowed for an integrated analysis and evaluation of potential measures, and (ii) the robustness of the measures for climate change, and allowing the selection of a set of measures providing a desired level of system resilience. As such the results of the study form the backbone for the development of a future vision on estuary management, while the model instrument will continue to be used to study design alternatives and finetune measures for implementation.
Changes of Channel Conditions of Zhangjiazhou Waterway for the 2020 Hydrological Year and Maintenance Countermeasures
Authors: Xu Hui , Shang Qianqian , Xu Xiangjun
Published: February 2023

The 2020 hydrological year is featured with the high-water level and high flow period far exceeding the previous hydrological years. The sediment deposition in flood season shallowed and impeded the channel. Based on the hydrological analysis of 2020, the impact of the catastrophic flood year on the channel conditions in the upper shallow area of Nangang, and the reasons for the deterioration of the channel conditions in the shallow area are analyzed. Meanwhile, channel maintenance countermeasures, the necessity of emergency dredging, and the specific dredging scheme are proposed accordingly. The results show that: the upper shallow area of Nangang followed the law of silting in flood season and scouring in the dry season during a hydrological year. The channel conditions depend on the comparison between silting in the flood season and scouring after the flood season. In 2020, the flood lasted for a long time, so the water-falling period was relatively insufficient after flood season, and the upper shallow area was not sufficiently scoured, which resulted in navigation obstruction in the upper shallow area. Therefore, emergency dredging was necessary to be implemented on the channel, the dredging site was designed from #10 navigational mark to #9 navigational mark, the dredging bottom elevation was 4.2 m below the design water level, and the dredging width was 200 m. Considering the hysteresis of riverbed deformation, it is suggested to pay continuous attention to the water conditions and channel variation in the upper shallow area of Nangang in the future, and to formulate corresponding channel maintenance countermeasures.
Complementarity and the unitarity of the black hole S-matrix
Authors: Kim Isaac H. , Preskill John
Published: February 2023

Abstract

Recently, Akers et al. proposed a non-isometric holographic map from the interior of a black hole to its exterior. Within this model, we study properties of the black hole S-matrix, which are in principle accessible to observers who stay outside the black hole. Specifically, we investigate a scenario in which an infalling agent interacts with radiation both outside and inside the black hole. Because the holographic map involves postselection, the unitarity of the S-matrix is not guaranteed in this scenario, but we find that unitarity is satisfied to very high precision if suitable conditions are met. If the internal black hole dynamics is described by a pseudorandom unitary transformation, and if the operations performed by the infaller have computational complexity scaling polynomially with the black hole entropy, then the S-matrix is unitary up to corrections that are superpolynomially small in the black hole entropy. Furthermore, while in principle quantum computation assisted by postselection can be very powerful, we find under similar assumptions that the S-matrix of an evaporating black hole has polynomial computational complexity.
Critical Points of the Solutions to the $$H_R=H_L$$ Surface Equation
Authors: Albujer Alma L. , Caballero Magdalena
Published: February 2023

Spacelike surfaces with the same mean curvature in $${\mathbb {R}}^3$$

R

3

and $${\mathbb {L}}^3$$

L

3

are locally described as the graph of the solutions to the $$H_R=H_L$$

H
R

=

H
L

surface equation, which is an elliptic partial differential equation except at the points at which the gradient vanishes, because the equation degenerates. In this paper we study precisely the critical points of the solutions to such equation. Specifically, we give a necessary geometrical condition for a point to be critical, we obtain a new uniqueness result for the Dirichlet problem related to the $$H_R=H_L$$

H
R

=

H
L

surface equation and we get a Heinz-type bound for the inradius of the domain of any solution to such equation, improving a previous result by the authors. Finally, we also get a bound for the inradius of the domain of any function of class $${\mathcal {C}}^2$$

C

2

in terms of the curvature of its level curves.
A New Description of the Complex Roots Using Zeros of Some Polynomials
Authors: Ludew Jakub Jan , Różański Michał , Słowik Roksana , Wituła Roman
Published: February 2023

Inspired by a problem found in a textbook of Faddeev and Sominsky we propose a new form of roots of an arbitrary complex number. Our idea uses the zeros of some polynomials connected with the modified Chebyshev polynomials.
Employment protection and regional self-employment rates in an economic downturn: a multilevel analysis
Authors: Filippopoulos Nikolaos , Fotopoulos Georgios
Published: February 2023

This research aims to investigate the role of employment protection in affecting the relationship between regional self-employment and unemployment during turbulent times. In doing so, data comprised of 230 regions, nested in 17 EU countries, for the 2008–2015 period were used. When accounting for individual effects, we find that an increase in regional unemployment would decrease regional self-employment, while the opposite was found true for employment protection. When accounting for the cross-level interaction between regional unemployment and national employment protection legislation, however, we find that the underlying increased labor market rigidity not only decreases regional self-employment, but it also magnifies the adverse effect of regional unemployment. Our key results thus indicate that high labor market rigidity hinders self-employment.
Application of optimized convolutional neural network to fixture layout in automotive parts
Authors: Villena Toro Javier , Wiberg Anton , Tarkian Mehdi
Published: February 2023

Fixture layout is a complex task that significantly impacts manufacturing costs and requires the expertise of well-trained engineers. While most research approaches to automating the fixture layout process use optimization or rule-based frameworks, this paper presents a novel approach using supervised learning. The proposed framework replicates the 3-2-1 locating principle to layout fixtures for sheet metal designs. This principle ensures the correct fixing of an object by restricting its degrees of freedom. One main novelty of the proposed framework is the use of topographic maps generated from sheet metal design data as input for a convolutional neural network (CNN). These maps are created by projecting the geometry onto a plane and converting the Z coordinate into gray-scale pixel values. The framework is also novel in its ability to reuse knowledge about fixturing to lay out new workpieces and in its integration with a CAD environment as an add-in. The results of the hyperparameter-tuned CNN for regression show high accuracy and fast convergence, demonstrating the usability of the model for industrial applications. The framework was first tested using automotive b-pillar designs and was found to have high accuracy (≈ 100%) in classifying these designs. The proposed framework offers a promising approach for automating the complex task of fixture layout in sheet metal design.
Long-term clinical outcomes of gastric mucosa-associated lymphoid tissue lymphoma in real-world experience
Authors: Min Gi-June , Kang Donghoon , Lee Han Hee , Kim Seung-Jun , Kim Tong Yoon , Jeon Young-Woo , O Joo Hyun , Choi Byung-Ock , Park Gyeongsin , Cho Seok-Goo
Published: February 2023

This long-term, retrospective, single-center study evaluated real-world clinical outcomes of gastric mucosa-associated lymphoid tissue (MALT) lymphoma using different therapeutic modalities and analyzed factors affecting survival outcomes and long-term prognosis. We enrolled 203 patients with pathologically confirmed low-grade gastric MALT lymphoma and examined their treatment responses. Helicobacter pylori eradication was performed in all patients with H. pylori infection (HPI) and localized stage gastric MALT lymphoma. All patients underwent pre-treatment and physical evaluations, with complete blood count, biochemistry panel, and staging workup. Among 144 HPI-positive patients with stage I or II1–2 disease who underwent H. pylori eradication, 112 (77.8%) achieved complete remission (CR). All HPI-negative patients who received first-line radiotherapy achieved CR (100%), but only 22 of 27 first-line chemotherapy-treated patients achieved CR (81.5%). Lesions in the proximal upper-third or in multiple locations and an invasion depth to the submucosa or deeper were associated with poor response to eradication, and HPI negativity was significantly correlated with poor progression-free survival. HPI eradication treatment should be the first-line treatment for patients with localized stage HPI-positive gastric MALT lymphoma. The “watch-and-wait” strategy should be adopted for delayed responders. We suggest radiotherapy for patients with a localized HPI-negative status or when eradication has failed.