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The purpose of this paper is to propose robust optimization models addressing the container slot allocation problem with minimum quantity commitment (MQC) under uncertain demand, which is faced by international companies export to USA.

A novel robust optimization approach handling linear programming (LP) with right-hand-side uncertainty is developed by incorporating new parameters: uncertainty level, infeasibility tolerance and reliability level. Two types of uncertainty, namely, bounded uncertainty and symmetric uncertainty are considered, respectively.

The present work finds that the expected revenue increases as the uncertainty level and the MQC decrease, as well as the infeasibility tolerance and the reliability level increase, no matter which type of uncertainty is considered.

Typically, the capacity constraints in a container shipping model should include two major restrictions: (1) number of slots and (2) total weight of loaded and empty containers. However, this study only addresses the first restriction for simplicity. It is recommended that future research explore the optimal solutions with additional restriction (2).

This paper fills a theoretical and practical gap for the problem of slot allocation with MQC in container liner revenue management. Deterministic and tractable mixed integer LP is formulated to derive robust solutions which immunes to demand uncertainty. Illustrative examples are presented to test the proposed models. The present work provides practical and solid advice and examples which demonstrates the application of the proposed robust optimization approach for logistics managers.

Physical gatherings at social events have been found as one of the main causes of COVID-19 transmission all over the world. Smartphone has been used for contact tracing by exchanging messages through Bluetooth signals. However, recent confirmed cases found in venues indicated that indirect transmission of the causative virus occurred, resulting from virus contamination of common objects, virus aerosolization in a confined space or spread from inadequate ventilation environment with no indication of human direct or close contact observed.

This paper presents a novel cyber-physical architecture for spatial temporal analytics (iGather for short). Locations with time windows are modeled as digital chromosomes in cyberspace to represent human activity instances in the physical world.

Results show that the high spatial temporal correlated but indirect tracing can be realized through the deployment of physical hardware and spatial temporal analytics including mobility and traceability analytics. iGather is tested and verified in different spatial temporal correlated cases. From a management perspective of mobilizing social capacity, the venue plays not only a promotion role in boosting the utilization rates but also a supervision-assisted role for keeping the venue in a safe and healthy situation.

This research is of particular significance when physical distancing measures are being relaxed with situations gradually become contained. iGather is able to help the general public to ease open questions: Is a venue safe enough? Is there anyone at a gathering at risk? What should one do when someone gets infected without raising privacy issues?

This study contributes to the existing literature by cyber-physical spatial temporal analytics to trace COVID-19 indirect contacts through digital chromosome, a representation of digital twin technology. Also, the authors have proposed a venue-oriented management perspective to resolve privacy-preserving and unitization rate concerns.

The purpose of this paper is twofold: to investigate performance of both manufacturer-owned channel and traditional retail channel when the manufacturer encroaches upon the traditional channel in different forms (brick-and-mortar and online form) under different market structures (Stackelberg and Bertrand). To examine the effect of acceptance of the online channel and travel cost on profits of two channels.

The Hotelling model is employed to depict consumers ' channel choice behavior, where the consumer surplus captures travel cost, spatial distance and consumer heterogeneity in acceptance of the online channel. A game-theoretical framework is developed to determine the optimal encroachment form and market structure for both manufacturer-owned and traditional retail channels.

This paper finds that, in either form of encroachment, Stackelberg market structure always outperforms Bertrand market structure, and channel choice significantly relies on parameters, i.e. consumer acceptance of the online channel and travel cost. Moreover, a Pareto zone is proposed in which both channels consider the strategy that the manufacturer opens bricks-and-mortar channel under Stackelberg market structure as the optimal strategy.

The present work fills a theoretical and practical gap for a structured analysis of the channel performance when the manufacturer encroaches upon the incumbent retail channel in different forms and under different market structure.

The purpose of this paper is to investigate the effects of product substitutability on sales performance of integrated and decentralised supply chains. The authors model supply chain performance effects by applying a Cournot equation to a combination of different industry configurations. The study aims to extend existing equilibria models in different supply chains by including the effects of product substitutability on supply chain performance. By extending existing equilibria models, the authors explore the relationship between the degree of product substitutability, chain structure and chain performance when some actors of the supply chain behave as Stackelberg leaders in a duopoly.

The paper models a supply chain performance by applying a Cournot equation to different supply chain structures in a duopoly.

The findings indicate that, for each specific-supply chain structures in different market configurations, when product substitutability reaches a certain threshold decentralised supply chains outperform integrated chains, in disagreement with common belief in current existing literature.

The study is limited to the application of differential equations in a competitive market configured as a duopoly. Future studies might extend the same model to a competitive market characterised by more than two actors. The findings imply that current tendency of lean implementations through integrated supply chains does not always favour supply chain performance.

The paper includes implications for the development of a stronger differentiation strategy based on consumer value when markets are characterised by high-product substitutability.

These findings highlight the importance of differentiation and consumer-value generation in markets that follow Nash equilibria as opposed to the current focus on price competition.

This paper aims to report a comprehensive analysis of literature on stakeholder relationships towards identifying patterns of relationships within the off-site construction context.

Key scholarly databases were accessed and after a filtering process, 74 relevant papers were retrieved for analysis. The papers were analysed using qualitative content analysis and scientometric techniques through the application of software Leximancer and VOSviewer.

Research synthesis methods used in the present study generate compatible results. Through text mining analysis, the key themes identified in the off-site construction stakeholder relationships literature included “collaboration”, “building information modelling”, “social network analysis”, supply chain. As a finding by scientometric analysis, collaboration, BIM, supply chain management, housing and social network analysis were the most frequently entered keywords context of off-site construction. Regarding authorship pattern, the whole network of collaboration was fragmented into multiple isolated clusters, implying that the authors had tendency to cooperate in small groups.

The paper can bring together an important area of research not previously studied in detail. It will primarily assist academics in the first instance; however, the research leads to important findings that will ultimately assist policymakers and practitioners better understand factors affecting stakeholder relationships and in particular network thinking and collaborative mind-sets.

The review contributes a needed systematic and theoretical foundation for future stakeholder relationship studies and practices in off-site construction sector. It provides the basis for future studies and is a seminal analysis of stakeholder management and off-site construction. The scientometric methodology offers scholars a different approach to analysing and visualising literature reviews.

The purpose of the study was to explore heat-accumulative and thermal-conductive characteristics of copper-graphene composite film (Cu-G film) while applying it to a human-skin analogue.

In the preliminary experiment, the authors evaluated the thermal conductive characteristics of the Cu-G film in three covered conditions (no film, copper film, and Cu-G film conditions). For the first factorial experiment, the heat-accumulative properties over heated pig skin were compared at air temperatures of 10, 25 and 35°C. For the second factorial experiment, 105 trials were conducted on pig skin by combining air temperatures, trapped air volumes, and numbers of film layers.

The results from the preliminary experiment showed that the Cu-G film distributed the surface heat to the outside of the Cu-G film, which resulted in even distribution of heat inside and outside the Cu-G film, whereas the copper film accumulated heat inside the copper film. The human-skin analogue of pig skin, however, showed the opposite tendency from that of the plastic. The pig-skin temperatures beneath the Cu-G film were higher than those beneath the copper film, and those differences were remarkable at the air temperature of 10°C. The accumulative heat was affected by the trapped air volume, fit to the skin, and number of Cu-G film layers.

In conclusion, the Cu-G film more effectively accumulated heat on the human-skin analogue than copper film, and those effects were more marked in cold environments than in mild or hot environments.

The Israeli National Police began to implement community policing on a large scale in January of 1995. In this paper we describe the main findings of a three year national evaluation of community policing in Israel that was initiated by the Chief Scientist’s office of the Israeli police in the Fall of 1996. When community policing was envisioned and planned in Israel it was seen as part of a total reformation of the Israeli police in structure, philosophy and action. Our research suggests that this broad idea of community policing was not implemented in Israel, and indeed the program of community policing was found to lose ground during the course of our study. While community policing did have specific impacts on the Israeli police, it did not fundamentally change the perspectives and activities of street level police officers. We explain the difficulties encountered in the implementation of community policing in reference to three factors: the speed of implementation of the program; the resistance of traditional military style organizational culture within the Israeli police to the demands of community policing models; and a lack of organizational commitment to community policing. In our conclusions we argue that these barriers to successful community policing are not unique to the Israel case, and are indeed likely to be encountered in the development of community policing in many other countries.