Ship Size and Service Configuration in Container Shipping

This study analyzes the effect of ship size on the liner service configuration by establishing an economic model. The service configuration is characterized by the distance of service and the number of calling ports. A study ease is presented for illustration. At last such a conclusion is drawn that given a fixed profit, the ship size will change with the extension of service in the same direction, while the change rate of ship size is a little higher than that of the extension of service.

Structural Characteristics and Evolution of a Weighted Sino-US Container Shipping Network

This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports.

Corporate Social Responsibility and Shipping Supply Chain Risks

This study aims to investigate whether Corporate Social Responsibility(CSR)activities reduce supply chain disruptions by examining the impact of the Suez Canal obstruction on the Ever Given container ship in March 2021.This study conclude that the more responsible companies have higher returns and are less affected by this event than the less responsible companies;the less responsible companies have lower returns.The companies with better CSR have a lower impact on their supply chains when faced with disruptions in the supply chain.

Robust Optimization Model for Resource Allocation of Container Shipping Lines

The operating efficiency of container shipping lines depends on proper resource allocation of container shipping.A deterministic model was developed for shipping lines based on the equilibrium principle.The objective was to optimize the resource allocation for container lines considering ship size,container deployment,and slot allocation.The deterministic model was then expanded to a robust optimization model accounting for the uncertain factors,while ship size was treated as the design variable and slot allocation as the control variable.The effectiveness of the proposed model is demonstrated using a pendulum shipping line as an example.The results indicate that infeasible solutions will increase and the model robustness will be enhanced by an increased penalty coefficient and the solution robustness will be enhanced by increasing the preference coefficient.The optimization model simultaneously considers demand uncertainty,model robustness,and risk preference of the decision maker to agree better with actual practices.

High Strength Steel Plates for Large Container Ships

Heavy thickness steel plates with a good combination of strength,toughness and weldability have been demanded for building of large container ships.High strength steel plates with heavy gauge of EH36,EH40 and EH47 grades were developed by optimizing chemical compositions and TMCP process parameters.Micro alloying elements of Ti and Nb were added to the three steel grades for enhancing the strength and toughness of base plates.The strength of base plates of the EH47 grade was further enhanced with the help of the increased amount of substitutional solid solutes,such as manganese,copper,nickel,or chromium.EH36 steel plates for high heat input over 550 kJ/cm were manufactured by improving thermal stability of TiN particles for better weld heat-affected zone toughness.Thermally stabilized TiN particles effectively suppress grain growth at weld heat-affected zone,leading to better toughness.These steel plates showed excellent mechanical properties of base plates and welded joints.

URANS simulations for a free-running container ship:Part 1. Turning-circle

The incompressible unsteady Reynolds-averaged Navier-Stokes(URANS)simulations are performed for a free-running container ship in maneuvering conditions:the starboard and portside turning circle simulations with 35°rudder deflection.The validation variables include trajectory,motions,and propeller performances,and the prediction shows acceptable agreements against the experimental data.During the steady-state part of the turning,the inertial forces balancing the local forces are reported to quantitatively assess the centrifugal force which appears from the force equilibrium between the rudder,propeller,and the bare-hull.The study on the local flow focuses on finding the correlations between the propeller inflow and the propeller performance to investigate the differences in propeller performances during the portside and starboard turning.The preliminary simulations,performed with the grid triplet,comprise propeller open-water,resistance,and self-propulsion simulations,from which the validation studies and the studies for the local force and the local flow are fulfilled and applied for the main simulations.Both propeller and rudder are fully discretized and controlled,mimicking the experiment.Level-set,overset approach and Mentor’s SST model are employed for the free-surface capturing,large motion prediction,and turbulence closure.

URANS simulations for a free-running container ship:Part 2. Added power

Part 2 reports the validation,local force and local flow study results for the free-running added power simulations whose conditions are the same as the self-propulsion test except for the increased propeller rotational speed and the presence of wave.When targeting the same mean Froude number in the wave condition,the propeller requires the increased propeller rotational speed for the operation at the low advance ratio due to the added resistance.The test is performed at five different wavelengths in head waves and four different headings in the oblique waves.For the validation study,the time series of the validation variables is decomposed with discrete Fourier transform to extract the harmonic values.Validation variables are global parameters,including motions,propeller thrust,and torque coefficients,added power variables,and self-propulsion factors which show reasonable agreement against the experiment results and produces a similar error from the self-propulsion simulation.The local force study shows that the added resistance mostly appears at the bow due to the bow plunging during the short head wave and resonance condition.The contributions of the gravitational force and the buoyant force are found to increase as the stern motion exceeds the bow motion during the long head wave condition.The oscillation of the propeller performances shows correlation with the first harmonic amplitude of the propeller inflow.Heave,pitch,and roll decay tests are performed prior to the main test to assess the natural frequencies of the ship.Same as Part 1,a discretized propeller is used.

Ship Fuel and Carbon Emission Estimation Utilizing Artificial Neural Network and Data Fusion Techniques

Ship energy consumption and emission prediction are the main concern of the shipping industry for ship energy efficiency management and pollution gas emission control. And they are attracting more global attention and research interests because of the increase in global shipping trade volume. As the core of maritime transportation, a large volume of data is collected around ships such as voyage data. Due to the rapid development of computational power and the widely equipped AIS device on ships, the use of maritime big data for improving and monitoring ship’s energy efficiency is becoming possible. In this paper, a fuel consumption and carbon emission model using the artificial neural network (ANN) framework is proposed by using AIS, ship machinery, and weather data. The proposed work is a complete framework including data collection, data cleaning, data clustering and model-building methodology. To obtain the suitable parameters of the model, the number of neurons, data inputs and activate functions were tested on both AIS-based data and MRV-based data for comparison. The results show that the proposed method can provide a solid prediction of ship’s fuel consumption and carbon emissions under varying weather conditions.

不同装载条件下小型渔船参数横摇的非定常RANS CFD仿真

Fishing boats have unique features that make them prone to changing loading conditions.When the boat leaves the port,the empty fish tank gradually fills up during fishing operations which may result in parametric roll(PR).This dangerous phenomenon that can lead to capsizing.The present study aims to understand better the behaviour of parametric roll in fishing boats and its relation to changing loading conditions.The study considers the effects of displacement and the GM/KM ratio on parametric roll,as well as the longitudinal flare distribution at the waterline.Two assessments to detect the parametric roll occurrence in early stage were carried out by using the level 1 assessment of parametric roll based on the Second Generation of Intact Stability criteria(SGIS)from International maritime Organisation(IMO)and the Susceptibility criteria of Parametric roll from the American Bureau of Shipping(ABS).Then,the CFD method is used to predict the amplitude of the parametric roll phenomenon.The results provide important insights to fishing vessel operators on how to manage loading conditions to maintain stability and avoid hazardous situations.By following the guidelines outlined in this study,fishing boats can operate more safely and efficiently,reducing the risk of accidents and improving the overall sustainability of the fishing industry.

Port and Shipping Express Management: The Challenges Faced by West and Central Africa in This Century

Shipping industry has become more capital intensive, technically more demanding and subject to major global regulatory reforms. As a consequence, the number of African shipping lines has been severely reduced. International trade of the WCA countries remains weak, limited to 30% of their Gross Domestic Product (GDP). The goal of this paper is to provide a comprehensive overview of the port and shipping convey management in the WCA region, and of course to describe what has been achieved since then and what still have to be done to better its infrastructures and port community.

集装箱班轮联营系统协同测度方法与实证

针对集装箱班轮联营系统的协同运作绩效问题,本文提出相应协同测度方法和模型,并进行实证应用研究.结合国际航运实际,应用协同理论方法,确定集装箱班轮联营系统协同机制框架,选取班轮联营实际运作指标,构建协同测度模型和评价体系,并以协同度来度量集装箱班轮联营系统的协同状况.以典型的CKYH集装箱班轮联营系统为实证案例,对该问题进行方法和模型的验证.研究结果表明,集装箱班轮联营系统协同度体现在系统各构成部分和系统要素的相互作用中,方法和模型能够有效地测度联营系统协同状况,研究结果符合航运实际,检验了该方法和模型的有效性.

Scale effects on bow wave breaking of KCS ship model:Insights from DDES investigations

Ship bow wave breaking is a common phenomenon during navigation,involving complex multi-scale flow interactions.However,the understanding of this intense free surface flow issue is not sufficiently deep,especially regarding the lack of research on the impact of scale effects on bow wave breaking.This paper focuses on the benchmark ship model KCS and conducts numerical simulations and comparative analyses of bow wave breaking for three model scales under the condition of Fr=0.35.The numerical calculations were performed using the in-house computational fluid dynamics(CFD)solver naoe-FOAM-SJTU,which is developed on the open source platform OpenFOAM.Delayed detached eddy simulation(DDES)method is utilized to calculate the viscous flow field around the ship hull.The present method was validated through measurement data of wave profiles and wake flows obtained from model tests.Flow field results for three different scales,including bow wave profiles,vorticity at various sections,and wake distribution,were presented and analyzed.The results indicate that there is small difference in the bow wave overturning and breaking for the first two occurrences across different scales.However,considerable effects of scale are observed on the temporal and spatial variations of the free surface breaking pattern after the second overturning.The findings of this study can serve as valuable data references for the analysis of scale effects in ship bow wave breaking phenomena.

关于洋山港发展的战略思考

作为国家重大战略工程———洋山港的开港正迎接全球目光的聚焦,更牵动着邻近东亚大港的神经。为什么要建立洋山港,洋山港的发展前景如何,洋山港将对长三角乃至全国的经济影响何在,这些都是文章将要讨论的内容。

铁路1.5t小型箱管理条形码技术应用的探讨

集装化用具在铁路运输过程中扮演着重要的角色,为实现1.5t小型箱的精确轨迹追踪,通过阐述铁路1.5t小型箱的应用现状,分析1.5t小型箱使用过程中存在的问题,提出合理利用1.5t小型箱箱体两侧的条形码,在"铁路零散货物快运平台"系统中的"用具管理"模块中加入"扫码信息录入"子模块,建立1.5t小型箱数据库,加强信息系统关联等配置方案,构建条形码技术应用于铁路1.5t小型箱管理的作业流程,以提高铁路1.5t小型箱管理质量,加强铁路零散货物运输竞争力。