Jing‐Xin Dong, Jingjing Xu and Dong‐Ping Song
Empty container repositioning is an important issue in the liner shipping industry. Generally stated, two groups of mathematical models have been proposed to tackle this issue…
Abstract
Purpose
Empty container repositioning is an important issue in the liner shipping industry. Generally stated, two groups of mathematical models have been proposed to tackle this issue. The first group aims to derive time‐dependent origin‐destination matrices that specify the number of empty containers to be repositioned at a decision epoch; the second group aims to develop effective state‐feedback control policies consisting of dynamic decision‐making rules. There is, however, a lack of research into the comparison of these two groups, especially with regard to realistic cases subject to uncertainties. The purpose of this paper is to evaluate and compare the performances of some typical repositioning policies from these two groups and to shed light on their relative merits and suitability in various realistic scenarios.
Design/methodology/approach
Based on a literature review, the paper classifies the current empty container repositioning policies into two categories: origin‐destination (OD) based solutions and state‐based dynamic rules. Typical policies are selected from these two categories and then evaluated using a simulation tool. A range of scenarios are designed based on realistic cases considering the stochastic and dynamic nature of liner services. A comprehensive set of simulation experiments are conducted and analysed; and the relative merits and suitability of the repositioning policies are identified.
Findings
Through a carefully designed comparative study, several research findings are obtained with regard to how the performances of different types of empty container repositioning policies are affected by various factors such as structure of service route, uncertainty of daily demands, and parametric optimisation methods.
Originality/value
The study makes a good attempt to analyse the suitability of different empty container repositioning policies in different scenarios. This is an area that has lacked investigation. The research findings can help shipping companies and other relevant stakeholders better understand the relative merits of different empty container repositioning policies and better tackle the challenges in operating the container shipping system.
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Abolfazl Gharaei, Seyed Hamid Reza Pasandideh and Alireza Arshadi Khamseh
The main purpose is to minimize the total inventory cost of chain, whereas the stochastic constraints are satisfied. In other words, the goal is to find optimum agreed stockpiles…
Abstract
Purpose
The main purpose is to minimize the total inventory cost of chain, whereas the stochastic constraints are satisfied. In other words, the goal is to find optimum agreed stockpiles and period length for products to minimize the total inventory cost of the chain while the stochastic constraints are fulfilled.
Design/methodology/approach
This paper designs and optimizes an integrated inventory model in a four-echelon supply chain that contains a supplier, a producer, a wholesaler and multiple retailers. All four levels agree with each other to make an integrated inventory system. Products in this model have a multi-stage production process, and the model is bounded by multiple stochastic constraints. The problem model is nonlinear and large. So, the interior point method as an effective algorithm is used for solving the recent convex nonlinear model. Two numerical examples are solved to demonstrate the application of this methodology and to evaluate the performance of the proposed approach.
Findings
The findings showed the model is applicable for real-world supply chain problems in the cases that echelons are going to do executive external integration. Also, the Interior Point algorithm has a satisfactory performance and a high efficiency in terms of optimum solution for solving nonlinear and large models.
Originality/value
The authors designed and optimized the inventory cost in a four-level integrated supply chain in stochastic conditions. The new decision variables, number of chain levels, multi-products, stochastic constraints and multi-stage products in four-level integrated supply chain are other novelties of this paper. The authors provided an efficient algorithm for solving a large-scale and nonlinear model in this research, too.
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De-gan Zhang, Ya-meng Tang, Yu-ya Cui, Jing-xin Gao, Xiao-huan Liu and Ting Zhang
The communication link in the engineering of Internet of Vehicle (IOV) is more frequent than the communication link in the Mobile ad hoc Network (MANET). Therefore, the highly…
Abstract
Purpose
The communication link in the engineering of Internet of Vehicle (IOV) is more frequent than the communication link in the Mobile ad hoc Network (MANET). Therefore, the highly dynamic network routing reliability problem is a research hotspot to be solved.
Design/methodology/approach
The graph theory is used to model the MANET communication diagram on the highway and propose a new reliable routing method for internet of vehicles based on graph theory.
Findings
The expanded graph theory can help capture the evolution characteristics of the network topology and predetermine the reliable route to promote quality of service (QoS) in the routing process. The program can find the most reliable route from source to the destination from the MANET graph theory.
Originality/value
The good performance of the proposed method is verified and compared with the related algorithms of the literature.
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Established on the detailed exploration of Chinese ancient management philosophies (CAMPs), the purpose of this paper is to extract enlightenments from CAMPs to see whether there…
Abstract
Purpose
Established on the detailed exploration of Chinese ancient management philosophies (CAMPs), the purpose of this paper is to extract enlightenments from CAMPs to see whether there exist some similarities between CAMPs and contemporary human resources management thoughts (CHRMTs) and pinpoint CAMPs' implications on human resource management practices nowadays.
Design/methodology/approach
Inspired by Lao Tzu's “When we can lay hold of the Dao of old to direct the things of the present day, and are able to know it as it was of old in the beginning, this is called (unwinding) the clue of Dao”, the paper explores, categorizes and integrates wisdom stemmed from CAMPs to evaluate whether there exist some commonly accepted arguments between CAMPs and CHRMTs.
Findings
CAMPs which have been passed on by generations for the past 2,500 years in China provide firm ground for human resources management thoughts and practices development; CAMPs' emphasis on people's well cultured morality and highly developed virtues has kindled a light to illuminate human resources management practices, not only in the past but also in the future. CHRMTs' principles concerning “people‐centered strategies”, employee recruitment and selection strategies, employee training and education strategies, staffing as well as employee retention strategies, can all trace their sources from CAMPs.
Originality/value
The research on CAMPs is not only significant to complement and extend CHRMTs but also useful to direct current human resource management practices.