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The objective of this paper is to quantitatively assess shear band evolution by using two-dimensional discrete element method (DEM).

The DEM model was first calibrated by retrospectively modelling existing triaxial tests. A series of DEM analyses was then conducted with the focus on the particle rotation during loading. An approach based on particle rotation was developed to precisely identify the shear band region from the surrounding. In this approach, a threshold rotation angle ω₀ was defined to distinguish the potential particles inside and outside the shear band and an index g(ω₀) was introduced to assess the discrepancy between the rotation response inside and outside shear band. The most distinct shear band region can be determined by the ω₀ corresponding to the peak g(ω₀). By using the proposed approach, the shear band development of two computational cases with different typical localised failure patterns were successfully examined by quantitatively measuring the inclination angle and thickness of shear band, as well as the microscopic quantities.

The results show that the shear band formation is stress-dependent, transiting from conjugated double shear bands to single shear band with confining stress increasing. The shear band evolution of two typical localised failure modes exhibits opposite trends with increasing strain level, both in inclination angle and thickness. Shear band featured a larger volumetric dilatancy and a lower coordination number than the surrounding. The shear band also significantly disturbs the induced anisotropy of soil.

This paper proposed an approach to quantitatively assess shear band evolution based on the result of two-dimensional DEM modelling.

The paper formulates a bi-objective mixed-integer nonlinear programming model, aimed at minimizing the total labor hours and the workload unfairness for the multi-skilled worker assignment problem in Seru production system (SPS).

Three approaches, namely epsilon-constraint method, non-dominated sorting genetic algorithm 2 (NSGA-II) and improved strength Pareto evolutionary algorithm (SPEA2), are designed for solving the problem.

Numerous experiments are performed to assess the applicability of the proposed model and evaluate the performance of algorithms. The merged Pareto-fronts obtained from both NSGA-II and SPEA2 were proposed as final solutions to provide useful information for decision-makers.

SPS has the flexibility to respond to the changing demand for small amount production of multiple varieties products. Assigning cross-trained workers to obtain flexibility has emerged as a major concern for the implementation of SPS. Most enterprises focus solely on measures of production efficiency, such as minimizing the total throughput time. Solutions based on optimizing efficiency measures alone can be unacceptable by workers who have high proficiency levels when they are achieved at the expense of the workers taking more workload. Therefore, study the tradeoff between production efficiency and fairness in the multi-skilled worker assignment problem is very important for SPS.

The study investigates a new mixed-integer programming model to optimize worker-to-seru assignment, batch-to-seru assignment and task-to-worker assignment in SPS. In order to solve the proposed problem, three problem-specific solution approaches are proposed.

Blockchain (BC) is a technological innovation that emphasizes the opposite paradigm compared to the available technology. This paradigm enables changing the firm’s business models (BMs) and has been elaborated by many experts. However, the discussion is scattered in various sources, particularly academic journals. This study aims to investigate the literature on the coexistence of BCs and BMs and depict the currently available situation that has not been discussed.

This study investigated articles focusing on the coexistence of BCs and BMs through heterogeneous academic databases, namely, Emerald, ProQuest, Taylor & Francis, ScienceDirect and Scopus. The systematic approach and development of inclusion criteria used in this study resulted in 52 key articles for further review. This systematic review followed the PRISMA framework and a timeframe between 2012 and 2022.

This study classifies literature based on specific themes, the integration of BC (interaction and evolution) and BM innovation (innovativeness, new value system and system logic), including the research design. As expected, the literature on BCs and BMs appears to be focused on particular themes since this topic appears to have grown. This study identifies gaps in the literature and describes future research to accommodate the study discrepancy.

The major limitation of this study is the research bias. Such a bias might occur due to the misinterpretations of researchers in this study. In the process of devising databases and keywords, this study identified the potential for misinterpretation. This study sought to use rigid protocols through a manual approach to mitigate the potential bias. A research bias also has the potential to arise in the literature classification. A literature categorization is performed back and forth, by referring to the theory or concept of a particular topic. The next limitation is limited access to scientific databases. This study drew upon several reputable scientific journal databases. However, the researcher considered the journal selection to be built upon a journal’s accessibility, multi-disciplinary nature and data size compared to other journals. It allows the analysis results to be biased, as they do not represent all available databases. However, the study used the available formal access to maintain the integrity of this research.

This study conducts a systematic review that discusses the coexistence of BCs and BMs. Furthermore, it provides a profound understanding of the discussion carried out through certain themes and the outlook for the future.