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Reclaiming–loading operations in dry bulk terminals often face conflicts and delays due to limitations in equipment processing capacity and operational line accessibility, which significantly compromise the safety and efficiency of these operations. This paper aims to optimize the reclaiming–loading schedule for each incoming vessel by considering parallel equipment operations and potential conflicts, with the goal of enhancing both the safety and efficiency of the loading processes. Through a detailed analysis of bulk reclaiming and reclaiming–loading mechanisms, we formulate the dry bulk terminal loading scheduling problem to minimize the total operational time for all loading tasks, taking into account constraints such as parallel reclaiming, collaborative loading, operational conflicts, and line accessibility. In order to obtain a good solution, including task execution sequences and allocation of reclaimers and shiploaders, a knowledge-driven memetic algorithm is developed by integrating knowledge-driven mechanisms with problem-specific operators within a memetic computing framework. Finally, numerical experiments for various scales are conducted using the layout and operational data from the Huanghua Port’s coal port area. The experimental results demonstrate the effectiveness of the proposed optimization algorithm.

Loading operation efficiency at airports plays an indispensable role in international air express service performance. The authors comprehensively examined the priorities of factors that affect loading operation efficiency for air express services at Taoyuan International Airport in Taiwan. The reviewed results from surveying practical experts using a rank pair-wise comparison (RPC) revealed that load factor and load planning consistently ranked higher and more crucial among 15 elements regardless of flight properties. Long-haul services to the North American hub were most concerned with inventory control of unit load devices (ULDs). Regional feeder services attached importance to the ground operations workforce as well. Feeder services for cross-continental deliveries additionally focused on the arrangement of apron bays. The authors used the TOPSIS, i.e., technique for order preference by similarity to ideal solutions, to evaluate flights by three freighter types. Considering that the studied company performed more consistently on the top crucial factors, the sub-criteria that belong to the negative subset and are affected by the external units played a dominant role in these evaluated flights.

In the traditional and extended shipboard operation human reliability analysis (SOHRA) model, the error-producing condition (EPC) is critical. The weight and proportion of each EPC in one specific task are often determined by the experts’ judgments, including most of the modified versions. Due to this subjectivity, the result and recommended safety measures may not be as accurate as they should be. This study attempts to narrow the gap by proposing a novel approach, a combination of SOHRA, entropy weight method, and the TOPSIS model. The entropy weight and TOPSIS method are employed to decide the weight of each EPC based on the foundation of the SOHRA model. A cargo-loading operation from a container ship is analyzed to verify this model. The results suggest that the entropy-weighted TOPSIS method can effectively determine the weights of EPCs, and the eight most probable human errors are identified.

To investigate the torque characteristics between dual-excitation (oil pressure of motor, drilling pressure of cylinder) and the lithology of coal seam under variable load conditions, the paper established a torque transmission model for the drilling rig, then narrated the production form of the dual-excitation. It also analyzed the force status of drilling tools in the process of drilling coal seam, and concluded the theoretical relationship between the dual-excitation and coal seam lithology of drilling coal seam. Theoretical research showed that the variation of dual-excitation could be used to predict the properties of coal seams. To simulate the dynamic response for dual-excitation of two kinds of samples during the drilling process under variable loading operation mode, the paper built up a test bench in a fully-hydraulic tunnel drill rig. The test results revealed a positive correlation between the hardness of the rock stratum and the dual-excitation. The research result could be used to predict the drillability of coal seams, so as to provide a reference for drilling technology.

Focused on chilldown procedure of liquid oxygen filling for second stage of a new generation launch vehicle, the method of chilldown through liquid oxygen pump has been put forward and compared with traditional method that of gas pressurization. The results showed that it could reduce total time, lower system state changes, and improve efficiency and reliability of liquid oxygen loading operations. Aimed at liquid oxygen flow of chilldown through the pump, the model of liquid oxygen pump operating has been established by considering variable frequency, regulating valve opening and liquid level of vehicle tank. It can provide scientific guidance and basis for flow control of chilldown through the pump and liquid oxygen tests.

Offshore crude oil offloading hoses are widely used in oil and gas transportation between the FPSO and oil tankers. The hoses are mainly affected by tensile and bending loads during the bow loading operation and are easily prone to failure under the combined tensile and bending loads. Based on this, the ABAQUS software was used to establish a nonlinear finite element model under tensile and bending loads and analyze the bending failure modes of the hose under different initial tensile loads. The results show that the crushing area of the hose under bending load occurs within the three-pitch range of the middle part of the hose. As the tensile load increases, the bending angle of the hose shows an increasing trend. Under different initial tensile loads, when the hose bend reaches 5.73°, the Von Mises stress of the hose helical wire reaches 766MPa. Appropriately increasing the initial tensile load will help avoid the ultimate collapse of the hose. The research results provide suggestions for the practical application of offloading delivery hoses.

This paper presents the results of the theoretical and computational analysis of the thermal processes during the desublimation of uranium hexafluoride and hydrogen fluoride in refrigerated containers. The technological scheme of the hydrogen fluoride desublimation in the containers refrigerated by the cold air is presented. We have substantiated the desublimation method of the uranium hexafluoride residues and hydrogen fluoride from the process stream into one container. The paper also provides the estimation of the maximum container loading, when the pressure of the saturated vapors above the surface of the desublimated mixture reaches the limiting value.

The optimization of cargo loading and transportation are two highly considered optimization problems (namely “3L-CVRP”). The combination of both has attracted increasing interest in the past decades. Hereby, 2D or 3D items have to be transported from one depot to a given set of customers using a homogeneous fleet of vehicles. Each route must be provided with a feasible packing plan taking various constraints into account. Combining the two optimization problems increases the complexity of the solution approaches, leading to a higher difficulty to check the results for correctness. To support the research progress and to enable transparency of solution structures, this paper provides an overview of recent literature, problem formulations, and best-known solutions. Furthermore, we introduce two open-source tools: The “Solution Validator” checks the feasibility of solutions in terms of considered constraints. The “Visualizer” provides two views and visualizes solutions. In the vehicle routing view, the tour plan and the corresponding schedule are displayed. In the loading view, the position of each item in the cargo space is demonstrated. In both views, it is possible to check the feasibility of the solution and highlight violated items. Besides the combined problem, the tool can be used also for one optimization problem (e.g. vehicle routing problem or container loading). The source codes for both tools are available at GitHub in C++ and Java and can be easily integrated into other researchers’ code.

The recent development of new offshore projects in pre-salt deepwater fields has placed offshore loading operations as the main production outflow alternative, increasing the operational complexity and risks. Numerous dangerous situations are associated with oil offloading, such as the messenger line transfer during the mooring stage. Nowadays, this critical task is realized by launching a thin messenger cable using the pneumatic line throwing apparatus. This is a complex and slow process since the operation usually occurs with the ship opposite to the wind. This work proposes a hybrid flight methodology based on computer vision and sensor fusion techniques for autonomous unmanned aerial vehicles (UAVs). The UAV takes off from an oil rig and precisely reaches a specific point in the shuttle tanker without using expensive positioning devices and augmenting UAV’s orientation (yaw) precision since the compass can suffer from severe interference due to naval metallic structures near the vehicle. The proposed framework was tested in a realistic simulated environment considering several practical operational constraints. The results demonstrated both the robustness and efficiency of the methodology.

Manufacturers usually store their products in palletized storage units (PSUs). PSUs are convenient for storage but sometimes not cost-effective for transportation because they may result in large empty spaces of waste in containers. To improve the utilization of its containers, a manufacturer is willing to remove products from PSUs (a process called depalletizing) and load the individual products, together with other PSUs, into a container. Once a PSU is depalletized, its products must be loaded into the container. No PSU can be depalletized if the total volume of complete PSUs loaded in the container is not maximized. We introduce this problem as the single container mix-loading problem (SCMLP). Then, we develop a two-phase constructive algorithm for the SCMLP that uses a stochastic beam-search-based method developed for loading items into a given set of spaces as the sub-routine. In the first phase, the stochastic beam-search-based method is called upon to load PSUs into the container. In the second phase, a proper set of PSUs is selected, and the stochastic beam-search-based method is used to load all products of the selected PSUs into the remaining spaces in the container. The performance of our algorithm is demonstrated by experiments conducted on a set of instances generated from the historical data of the manufacturer. Besides, we also used the well-known 1500 single container loading problem instances to test the performance of our stochastic beam-search-based method, and the results showed that our approach is highly competitive with state-of-the-art methods.