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This study aims to provide a comprehensive overview of the current state of the art in powder bed fusion (PBF) techniques for additive manufacturing of multiple materials. It reviews the emerging technologies in PBF multimaterial printing and summarizes the latest simulation approaches for modeling them. The topic of “multimaterial PBF techniques” is still very new, undeveloped, and of interest to academia and industry on many levels.

This is a review paper. The study approach was to carefully search for and investigate notable works and peer-reviewed publications concerning multimaterial three-dimensional printing using PBF techniques. The current methodologies, as well as their advantages and disadvantages, are cross-compared through a systematic review.

The results show that the development of multimaterial PBF techniques is still in its infancy as many fundamental “research” questions have yet to be addressed before production. Experimentation has many limitations and is costly; therefore, modeling and simulation can be very helpful and is, of course, possible; however, it is heavily dependent on the material data and computational power, so it needs further development in future studies.

This work investigates the multimaterial PBF techniques and discusses the novel printing methods with practical examples. Our literature survey revealed that the number of accounts on the predictive modeling of stresses and optimizing laser scan strategies in multimaterial PBF is low with a (very) limited range of applications. To facilitate future developments in this direction, the key information of the simulation efforts and the state-of-the-art computational models of multimaterial PBF are provided.

Bulk material-handling equipment development can be accelerated and is less expensive when testing of virtual prototypes can be adopted. However, often the complexity of the interaction between particulate material and handling equipment cannot be handled by a single computational solver. This paper aims to establish a framework for the development, verification and application of a co-simulation of discrete element method (DEM) and multibody dynamics (MBD).

The two methods have been coupled in two directions, which consists of coupling the load data on the geometry from DEM to MBD and the position data from MBD to DEM. The coupling has been validated thoroughly in several scenarios, and the stability and robustness have been investigated.

All tests clearly demonstrated that the co-simulation is successful in predicting particle–equipment interaction. Examples are provided describing the effects of a coupling that is too tight, as well as a coupling that is too loose. A guideline has been developed for achieving stable and efficient co-simulations.

This framework shows how to achieve realistic co-simulations of particulate material and equipment interaction of a dynamic nature.

Using composite indices, the paper examines the nexus between militarization, globalization and liberal democracy. The democratic peace theory, the conflict inhibiting effects of international trade – a key and dominant facet of globalization – and the democracy promoting globalization hypothesis form the theoretical underpinnings of the empirical investigation.

To probe into the issue at hand, the paper adopts a dynamic panel VAR estimation procedure. Given the usual data constraints, the sample consists of 113 countries, and the estimations span the period 1995–2019.

The findings from the dynamic panel VAR estimations suggest the presence of a negative and statistically significant nexus between the level of globalization and the level of militarization. No statistically traceable nexus between globalization and liberal democracy was found.

The findings offer empirical support to the hypothesis that the strong links of interdependence shaped by globalization reduce the need for military preparedness. The results lead to a tentative inference in favor of the doux commerce thesis. Nonetheless, given that the estimations span a historically specific period – the entire post-bipolar era – the inferences that stem from the findings should be treated with caution.

To the best of the authors’ knowledge, the composite indices Bonn International Centre for Conflict Studies (BICC) militarization index, the globalization index of the Swiss Economic Institute (Konjunkturforschungsstelle) (KOF), LibDem, polyarchy have not hitherto been jointly used in previous studies to examine the nexus between militarization, globalization and liberal democracy.

The article investigates whether variety of democracy affects the probability to employ public subsidies for credit support by small- and medium-sized enterprises (SMEs) led by female entrepreneurs.

Building on the literature on democracy and on gender differences, it leverages a large firm- and country-level dataset (SAFE) of 31 democracies in Europe (EU and non-EU) over the 2009–2014 period by using probit models and instrumental variable approaches.

Results from the different econometric techniques and samples suggest that variety of democracy affects female-led SMEs in using public subsidies for credit support. The evidence is robust to endogeneity concerns.

The empirical evidence presents a time frame limitation. At the same time, SAFE is the only database that supplies information about the gender of firms and public subsidies for credit support, rendering it the only resource that allows the test of the hypothesis proposed. The article therefore offers insights for scholars to revisit our results in future studies that make use of datasets with a longer time span – when they will become available.

To the best of the authors' knowledge, the article is the first to study the effect of democracy on female entrepreneurial behavior in the use of public subsidies for credit support.

Bangladesh is one of the most flood-prone countries in the world. A number of research works have identified that the flood scenario will be aggravated with climate change context in Bangladesh. In 2014, Bangladesh had prepared municipal level master plan for 222 municipalities with a view to planned urban development. But climate change-induced flood has not been considered in master plan, which poses a question toward the sustainability of the plan. Ullapara Municipality of Sirajganj district has been selected to conduct the research. This study aims to evaluate how infrastructure in proposed master plan will be exposed to climate change-induced flood.

The methodology of this study follows geographic information system (GIS)-based flood exposure analysis of selected infrastructure. These infrastructures include transport infrastructure, educational infrastructure, health infrastructure and other urban facilities. Climate change-induced flood for the year 2040 has been used for flood exposure analysis.

It is evident from the flood exposure analysis that about 33.99% roads will be exposed to 1.5 m–2 m inundation level; seven primary school, six secondary school and four colleges would be highly exposed to 2.0 m–2.50 m inundation level; four health facilities would be exposed to 1.0 m–2.0 m inundation level because of future climate change. This inundation scenario for long duration will lead to dysfunction of concerned infrastructure and, in turn, undermine the stability of a socioeconomic system of Ullapara Municipality.

As the master plan is not fully implemented till now, there is scope for intervention for considering climate change-induced flood to make the plan sustainable.

A search and rescue incident is ultimately all about the location of the missing person; hence, geotechnical tools are critical in providing assistance to search planners. One critical role of Geographic Information Systems (GISs) is to define the boundaries that define the search area. The literature mostly focuses on ring- and area-based methods but lacks a linear/network approach. The purpose of this paper is to present a novel network approach that will benefit search planners by saving time, requires less data layers and provides better results.

The paper compares two existing models (Ring Model, Travel Time Cost Surface Model (TTCSM)) against a new network model (Travel Time Network Model) by using a case study from a mountainous area in Austria. Newest data from the International Search and Rescue Incident Database are used for all three models. Advantages and disadvantages of each model are evaluated.

Network analyses offer a fruitful alternative to the Ring Model and the TTCSM for estimating search areas, especially for regions with comprehensive trail/road networks. Furthermore, only few basic data are needed for quick calculation.

The paper supports GIS network analyses for wildland search and rescue operations to raise the survival chances of missing persons due to optimizing search area estimation.

The paper demonstrates the value of the novel network approach, which requires fewer GIS layers and less time to generate a solution. Furthermore, the paper provides a comparison between all three potential models.

The purpose of this paper is to offer original ideas into a potential future cannabis industry in the UK. This paper presents novel approaches regarding the potential existence of cannabis for the tourism industry. It presents an idea in which the UK Government could produce, distribute and control the industry. The proposed idea presents a scheme in which the UK could encourage regional tourism (inclusive to domestic and international travellers) through a controlled but innovative cannabis market scheme. This paper presents a future scenario aiming to encourage dialogue and critique, at a time when attitudes to cannabis are changing.

This research takes a scenario narrative approach in presenting and exploring a potential future cannabis market in the UK. The importance of narrative writing as a method is recognised by Lindgren and Bandhold (2009), who identify the significance in telling a story to the reader. Taking a pragmatic approach, embracing diverse philosophical methods, this research explores past and current trends via a mixture of secondary data sources to create and present a scenario narrative of the future.

This paper identified that trends in legalising cannabis for cultivation, medical and recreational purposes continue to become more liberal globally. However, cannabis laws mainly focus on the use for residents. Consequently, domestic tourism markets have the potential to grow. However, there is limited consideration regarding the potential for international tourism cannabis markets. Thus, the findings of this research are based on the potential for the UK to implement and promote a cannabis industry for international travellers.

This paper offers original ideas in exploring a future cannabis market in the UK, one where regional tourism is considered. The paper presents a novel approach that encourages domestic and international tourists to engage with the cannabis industry by navigating a well-managed, local approach to supplying cannabis in the UK.