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Research Article
Exploring the Application of Computational Fluid Dynamics (CFD) Wind Environment Simulation in the Layout of Port Operation Areas
Lixiong Chen*,
Dongkui Wu,
Chun Shen
Issue:
Volume 8, Issue 6, November 2023
Pages:
128-134
Received:
4 October 2023
Accepted:
2 November 2023
Published:
11 November 2023
Abstract: The wind environment in port areas not only affects port planning and layout but also constrains the navigation time window during operations. During the engineering certification process for port construction, typically only monthly and yearly climatic characteristics of hydrological and meteorological conditions, as well as statistical conclusions on the main weather systems causing high winds and waves in the region, can be considered. These data alone cannot represent the wind and wave distribution in specific operational areas. Sometimes, it is necessary to refer to the wind and wave characteristics of the operational waters for specific port operation point selection. In such cases, remote sensing or simulation techniques, such as computational fluid dynamics (CFD), are used to infer the wind and wave distribution characteristics. Taking Shanghai Yangshan Deepwater Port as an example, the design of the pilot boarding point for strong winds and waves is located near the main channel, providing limited protection against high winds and waves. On average, there are 11.9 instances of pilot traffic control caused by high winds and waves each year. To mitigate the impact of severe weather on port operations, it is proposed to move the temporary boarding point for pilots in strong winds and waves westward to the east gate closer to the port area. Traditional hydrological and meteorological statistical data cannot support the selection of the new area, so it was decided to use CFD technology to simulate the wind environment in the relevant island and reef area and analyze the wind field distribution under different wind directions. Combined with the three-year statistical data from the meteorological station on Xiaoyangshan Island, a new area for the temporary pilot boarding point was selected. The CFD wind environment simulation results provided the primary technical support for determining the reference area.
Abstract: The wind environment in port areas not only affects port planning and layout but also constrains the navigation time window during operations. During the engineering certification process for port construction, typically only monthly and yearly climatic characteristics of hydrological and meteorological conditions, as well as statistical conclusion...
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Research Article
Graph Colouring to Solve Both Balanced and Unbalanced Transportation Problems
Oshan Niluminda*,
Uthpala Ekanayake
Issue:
Volume 8, Issue 6, November 2023
Pages:
135-144
Received:
5 October 2023
Accepted:
23 October 2023
Published:
11 November 2023
Abstract: Transportation is one of the various worldwide challenges that organizations must tackle. The Transportation Problem (TP) is also an important topic in the subject of optimization, where the aim is to reduce the overall transportation cost of distributing from a particular number of sources to a specific number of destinations (locations). This paper aims to investigate the most effective way to solve the Transportation Problem (TP) using the line (edge) colouring of a bipartite network. To solve the TP, several solutions have been proposed in the literature. The Initial Basic Feasible Solution (IBFS) and the Optimal Solution are the two solutions of TP. The North-West Corner Method (NWCM), the Lowest Cost Method (LCM), Row Minima Method (RMM), Column Minima Method (CMM), and Vogel's Approximation Method (VAM) may be used to find an IBFS, while the Modified Distribution (MODI) Method and the Stepping Stone Method can be used to find an optimal solution for the TP In this paper, propose a new algorithmic technique that utilizes the line (edge) colouring of a bipartite network to obtain an optimal or nearly optimal solution to the TP. The proposed technique is applied to balanced and unbalanced TP and compared to other existing methods. Experimental results show that the line (edge) colouring algorithm requires fewer iterations to achieve optimality compared to other current methodologies. In conclusion, the line (edge) colouring algorithm is a highly effective method for solving TP. By representing the TP as a bipartite network and using the proposed algorithmic technique, the optimum or nearly optimum TP solution can be obtained quickly and efficiently. This approach has significant potential for optimizing transportation logistics in various industries.
Abstract: Transportation is one of the various worldwide challenges that organizations must tackle. The Transportation Problem (TP) is also an important topic in the subject of optimization, where the aim is to reduce the overall transportation cost of distributing from a particular number of sources to a specific number of destinations (locations). This pap...
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Research/Technical Note
IOT-Based Erection Techniques for Main Cables of Nizhou Waterway Bridge of Nansha Bridge
Issue:
Volume 8, Issue 6, November 2023
Pages:
145-153
Received:
14 October 2023
Accepted:
6 November 2023
Published:
17 November 2023
Abstract: The Nizhou Waterway Bridge of the Nansha Bridge is a (658+1688+522) m two-span steel box girder suspension bridge. The main cables are erected by the prefabricated parallel steel wire strand (PPWS) method. Combined with the characteristics of main cable and strand, the efficiency and quality of strand erection are improved by optimizing the layout of traction system and improving the cable strand erection devices such as quick-dismantling suspension device, quick-dismantling puller for rear anchor head of back anchor cable and self-locking grip. Based on the Internet of Things technology, an intelligent monitoring system for cable strand erection including a real-time monitoring system for cable strand traction and a real-time monitoring and calculation system for cable strand adjustment is developed. The real-time monitoring system for cable strand traction carries out multi-dimensional monitoring, tracking and early warning of the cable strand traction process. The cable adjustment real-time monitoring and calculation system quickly monitors and combines the cable temperature field and height difference sensor data to calculate the cable sag and adjustment amount, and systematically generates and sends the cable adjustment instructions. The intelligent monitoring system of cable strand erection has preliminarily realized the intelligent monitoring of cable strand erection traction of suspension bridge, which effectively ensures the quality of the steel strands during the cable erection phase and the final as-built quality.
Abstract: The Nizhou Waterway Bridge of the Nansha Bridge is a (658+1688+522) m two-span steel box girder suspension bridge. The main cables are erected by the prefabricated parallel steel wire strand (PPWS) method. Combined with the characteristics of main cable and strand, the efficiency and quality of strand erection are improved by optimizing the layout ...
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Research Article
Research on Anti-Corrosion Solutions for Simplification OCS Components
Li Shaopeng,
Wang Guoliang,
He Changhong
Issue:
Volume 8, Issue 6, November 2023
Pages:
154-157
Received:
26 October 2023
Accepted:
14 November 2023
Published:
24 November 2023
Abstract: Simplification OCS equipment is a OCS equipment system with Chinese independent intellectual property rights. In recent years, more and more railroad projects have adopted this equipment system, which marks a big step forward in the process of China's OCS autonomy. However, its anti-corrosion process is not perfect, the current anti-corrosion measures are passivation, anodic oxidation and micro-arc oxidation three means, the anti-corrosion program is not mature. China's vast territory, the natural environment varies greatly from place to place, at the same time on the market a wide variety of anti-corrosion process, different projects, different locations using the anti-corrosion program is not uniform. This has a direct impact on both the manufacturing cost and the later maintenance cost. In this paper, through the service performance of existing parts, anti-corrosion measures to study the different forms of anti-corrosion process for the test, and ultimately achieve the purpose of unifying the anti-corrosion program of the Simplification OCS equipment. Propose anti-corrosion measures applicable to OCS equipment in different environments. Extend the service life of the equipment, improve the reliability of the contact network equipment and reduce the operation and maintenance cost while considering the economy. Realize the complementary improvement of Simplification OCS equipment technology system.
Abstract: Simplification OCS equipment is a OCS equipment system with Chinese independent intellectual property rights. In recent years, more and more railroad projects have adopted this equipment system, which marks a big step forward in the process of China's OCS autonomy. However, its anti-corrosion process is not perfect, the current anti-corrosion measu...
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Methodology Article
A Two-Stage Algorithm for Coastal Complex Water Route Planning Based on A* and Recursion
Dongkui Wu,
Fan Yang,
Lixiong Chen*
Issue:
Volume 8, Issue 6, November 2023
Pages:
158-165
Received:
16 November 2023
Accepted:
6 December 2023
Published:
22 December 2023
Abstract: Route planning is a crucial task in maritime navigation, as it ensures the safety of navigation and reduces fuel consumption. In order to further enhance the safety of vessel navigation in complex waterways, reduce sailing distances, and improve the convenience of vessel operations, this paper addresses the shortest path problem for vessel navigation in complex waterways. This problem aims to find a route with the shortest sailing distance and the fewest number of ship turning maneuvers in a complex water area, while ensuring navigation safety from the starting point to the destination. By abstracting the actual sailing process of vessels, the paper initially divides the navigation area into grids, and then differentiates between impassable and passable grids by inflating the boundaries of navigational obstacles. An integer programming model based on grid partitioning is formulated to describe this problem, and the optimality of the routes is analyzed. A two-stage algorithm is proposed to solve this problem, wherein the first stage utilizes the A* algorithm to find the shortest path from the starting point to the destination, and the second stage uses a recursive algorithm based on the path generated in the first stage to adjust turning points and further reduce the sailing distance. Finally, a simulation platform is built using Python, and the above algorithms are employed for experimentation. The experimental results demonstrate the effectiveness of the proposed model and algorithms.
Abstract: Route planning is a crucial task in maritime navigation, as it ensures the safety of navigation and reduces fuel consumption. In order to further enhance the safety of vessel navigation in complex waterways, reduce sailing distances, and improve the convenience of vessel operations, this paper addresses the shortest path problem for vessel navigati...
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