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1 – 10 of 39Mei Sha, Theo Notteboom, Tao Zhang, Xin Zhou and Tianbao Qin
This paper presents a generic simulation model to determine the equipment mix (quay, yard and intra-terminal transfer) for a Container Terminal Logistics Operations System…
Abstract
This paper presents a generic simulation model to determine the equipment mix (quay, yard and intra-terminal transfer) for a Container Terminal Logistics Operations System (CTLOS). The simulation model for the CTLOS, a typical type of discrete event dynamic system (DEDS), consists of three sub-models: ship queue, loading-unloading operations and yard-gate operations. The simulation model is empirically applied to phase 1 of the Yangshan Deep Water Port in Shanghai. This study considers different scenarios in terms of container throughput levels, equipment utilization rates, and operational bottlenecks, and presents a sensitivity analysis to evaluate and choose reasonable equipment ratio ranges under different operational conditions.
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Tianliang Wang, Ya-Meng He, Zhen Wu and Jun-jun Li
This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata…
Abstract
Purpose
This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata process, closure time and thickness evolution mechanism of the frozen wall.
Design/methodology/approach
In this paper several laboratory model tests were conducted, considering different groundwater seepage rate.
Findings
The results show that there is a significant coupling effect between the cold diffusion of artificial freezing pipes and groundwater seepage; when there is no seepage, temperature fields upstream and downstream of the gravel strata are symmetrically distributed, and the thickness of the frozen soil column/frozen wall is consistent during artificial freezing; groundwater seepage causes significant asymmetry in the temperature fields upstream and downstream of the gravel strata, and the greater the seepage rate, the more obvious the asymmetry; the frozen wall closure time increases linearly with the increase in the groundwater seepage rate, and specifically, the time length under seepage rate of 5.00 m d−1 is 3.2 times longer than that under no seepage; due to the erosion from groundwater seepage, the thickness of the upstream frozen wall decreases linearly with the seepage velocity, while that of the downstream frozen wall increases linearly, resulting in a saddle-shaped frozen wall.
Originality/value
The research results are beneficial to the optimum design and risk control of artificial freezing process in gravel strata.
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Pengyue Guo, Tianyun Shi, Zhen Ma and Jing Wang
The paper aims to solve the problem of personnel intrusion identification within the limits of high-speed railways. It adopts the fusion method of millimeter wave radar and camera…
Abstract
Purpose
The paper aims to solve the problem of personnel intrusion identification within the limits of high-speed railways. It adopts the fusion method of millimeter wave radar and camera to improve the accuracy of object recognition in dark and harsh weather conditions.
Design/methodology/approach
This paper adopts the fusion strategy of radar and camera linkage to achieve focus amplification of long-distance targets and solves the problem of low illumination by laser light filling of the focus point. In order to improve the recognition effect, this paper adopts the YOLOv8 algorithm for multi-scale target recognition. In addition, for the image distortion caused by bad weather, this paper proposes a linkage and tracking fusion strategy to output the correct alarm results.
Findings
Simulated intrusion tests show that the proposed method can effectively detect human intrusion within 0–200 m during the day and night in sunny weather and can achieve more than 80% recognition accuracy for extreme severe weather conditions.
Originality/value
(1) The authors propose a personnel intrusion monitoring scheme based on the fusion of millimeter wave radar and camera, achieving all-weather intrusion monitoring; (2) The authors propose a new multi-level fusion algorithm based on linkage and tracking to achieve intrusion target monitoring under adverse weather conditions; (3) The authors have conducted a large number of innovative simulation experiments to verify the effectiveness of the method proposed in this article.
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Buddhi A. Weerasinghe, H. Niles Perera and Phillip Kießner
This paper examines how the altering nature of planning decisions affects operational efficiency in seaport container terminals. The uncertainty and the role of the planner were…
Abstract
Purpose
This paper examines how the altering nature of planning decisions affects operational efficiency in seaport container terminals. The uncertainty and the role of the planner were investigated considering the dynamic integrated planning function of the quay to yard interface.
Design/methodology/approach
A system dynamics model has been built to illustrate the integrated dynamic environment. Data collection was conducted at a leading container terminal at a hub port. The model was simulated for different scenarios to derive findings.
Findings
The planner has been identified as the agent who makes alterations between the initial operational plan and the actual plan. The initial plan remains uncertain even when there is no impact from crane breakdowns, requiring a significant number of alterations to be made. The planner who had worked on the yard plan had altered (approximately 45%) the initial plan than the alterations done by the planner who had worked on the vessel plan. As a result, the feedback loop that is created by the remaining moves at each hourly operation influences the upcoming operation as much as crane breakdowns influence.
Originality/value
The uncertainty and the role of the planner were investigated considering the dynamic integrated planning function of the quay to yard interface. The findings of this study are significant since terminal efficiency is examined considering the quayside and landside as an integrated system.
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Low-carbon agricultural technology (LAT) extension is a key strategy for the agricultural sector to address climate change. Social capital, which consists of social networks…
Abstract
Purpose
Low-carbon agricultural technology (LAT) extension is a key strategy for the agricultural sector to address climate change. Social capital, which consists of social networks, trust and norms, can play an active LAT extension role. This paper aims to analyze the mechanism of the role of social capital in the process of LAT extension.
Design/methodology/approach
Questionnaire data from six counties in Jiangsu, China, were used to measure social capital and analyze its effect on LAT extension using logistic regression. Data from 27 interviews were used to analyze the LAT extension experiences and problems.
Findings
LAT is mainly deployed by the government to farmers and distributed among them. In this process, the village officials who form parts of the government’s composition and the villagers play a dual role that facilitates a close link between them and the farmers and ensures LAT integration. However, social norms did not play a significant role in the process.
Practical implications
Farmers’ acceptance of LAT is based solely on the trade-off between local networks’ benefits and trust in local villagers and village officials. LAT-related laws and technical measures, thus are essential to strengthen LAT practices’ authority and incorporate LAT-based agricultural production as the norm of production behavior.
Originality/value
This paper provides an insight into the process and essence of farmers’ acceptance of LAT, which provides theoretical lessons for the LAT extension in China and indeed other developing countries.
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