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The purpose of the paper is to show that land degradation and desertification are threatening the livelihood of more than a billion dryland inhabitants. The paper aims to present traditional and novel approaches for sustainable agricultural exploitation of the arid drylands in Southern Israel and similar climatic zones, and their potential for rehabilitating degraded drylands and increasing agricultural productivity.

The paper analyses the current agricultural activities on the Abu Rabia farm as well as developing experimental approaches and discusses the expected impact on ecological, economic and social sustainability.

The farm investigated consists of about 120 hectares of semi‐desert land 30 km east of Beer Sheva, divided about 50:50 between rocky hill country and plains with deep loess soil. The area receives an average 200 mm of rain per year. The land is used for raising livestock (about 120 head of sheep and goats), wheat cultivation on high quality soil, and agroforestry, mainly olive cultivation in terraces designed to collect runoff water of seasonal streams. These activities provide a basic income and cover a significant amount of the families' food requirements, but can not provide a full income for a family head in a developed country like Israel. Improving the quality of the grazing land by silvipasture, further investments into high value dryland tree crops and simultaneous production of wood for industry and energy can dramatically increase the farm's income, its resilience to drought and ecological sustainability.

This analysis demonstrates the potential of dryland agroforestry for sustainable development while solving a number of economic and social problems of poor dryland inhabitants, and it contributes to fighting desertification and global warming.

This case study demonstrates that sustainable dryland exploitation by agroforestry can establish significant agricultural production potentials on marginal lands often considered worthless. Because of the establishment of significant and permanent carbon sinks, carbon trading may be mobilized to cover the required investments creating a classical win‐win situation.

There are many investigations in design methodologies, but there are also divergences and convergences as there are so many points of view. This study aims to evaluate to corroborate and deepen other researchers’ findings, dissipate divergences and provide directing to future work on the subject from a methodological and convergent perspective.

This study analyzes the previous reviews (about 15 reviews) and based on the consensus and the classifications provided by these authors, a significant sample of research is analyzed in the design for additive manufacturing (DFAM) theme (approximately 80 articles until June of 2017 and approximately 280–300 articles until February of 2019) through descriptive statistics, to corroborate and deepen the findings of other researchers.

Throughout this work, this paper found statistics indicating that the main areas studied are: multiple objective optimizations, execution of the design, general DFAM and DFAM for functional performance. Among the main conclusions: there is a lack of innovation in the products developed with the methodologies, there is a lack of exhaustivity in the methodologies, there are few efforts to include environmental aspects in the methodologies, many of the methods include economic and cost evaluation, but are not very explicit and broad (sustainability evaluation), it is necessary to consider a greater variety of functions, among other conclusions

The novelty in this study is the methodology. It is very objective, comprehensive and quantitative. The starting point is not the case studies nor the qualitative criteria, but the figures and quantities of methodologies. The main contribution of this review article is to guide future work on the subject from a methodological and convergent perspective and this article provides a broad database with articles containing information on many issues to make decisions: design methodology; optimization; processes, selection of parts and materials; cost and product management; mechanical, electrical and thermal properties; health and environmental impact, etc.

The purpose of this paper is to investigate the development process of the fire whirl in the fixed-frame facility and focus on the impacts of the fire whirl’s vortex core on the formation and flame structure of the fire whirl.

The complex turbulent reacting flame surface is captured by the large eddy simulation turbulence closure coupled with two sub-grid scale (SGS) kinetic schemes (i.e. the chemistry equilibrium and steady diffusion flamelet). Numerical predictions are validated thoroughly against the measurements by Lei et al. (2015) with excellent agreements. A double maximum tangential velocity refinement approach is proposed to quantify the vortex cores’ instantaneous location and region, addressing the missing definition in other studies.

The numerical results show that the transition process of the fire whirl is dominated by the vortex core movement, which is related to the centripetal force. The unsteadiness of the fully developed fire whirl was found depending on the instantaneous fluctuation of heat release rate. The steady diffusion flamelet scheme is essential to capture the instantaneous fluctuation. Furthermore, the axial velocity inside the vortex core is the key to determining the state of fire whirl.

Due to intensive interactions between buoyant fires and ambient rotating flow, the on-set and formation of fire whirl still remain largely elusive. This paper focused on the transition process of fire whirl between different development stages. This paper provides insights into the transition process from the inclined flame to the fire whirls based on the centripetal force.

This paper presented and compared two SGS kinetic schemes to resolve the fire whirl development process and the unsteadiness of its vortical structures. The modelling framework addresses the shortcoming of previous numerical studies where RANS turbulence closure and simplified combustion kinetics was adopted. Numerical results also revealed the fire whirl transition process and its relationship to centripetal force.

The purpose of this paper is to develop a theory that is sufficiently adapted to sector competitiveness. The case of greenhouse vegetable production in The Netherlands and Switzerland is used to explain differences in sector competitiveness.

Interviews focusing on the fields of spatial planning, labor, energy supply, and market organization were carried out with stakeholders and producers in both countries and evaluated by Grounded Theory.

The work shows that the flexibility not only of producers, but also of the whole institutional framework in The Netherlands exceeds the flexibility on the Swiss side by far, which may be an important factor for explaining differences in competitiveness.

The result that it is a basic difference in flexibility and adaptability that determines sector competitiveness is valid for the vegetable sector. It should be examined whether similar patterns can be found in other sectors.

The competitiveness discussion is transferred to a new economic level, namely the economic sector. Likewise, new answers are found in looking for explanations for differences in competitiveness.

Successful teams tend to be highly cohesive and team cohesion to be particularly helpful in allowing teams and their members to sustain their success even in the most challenging times. One disillusioning consequence of this reciprocity between cohesion and performance would suggest that failures made by teams and/or their members likely jeopardize their success by preventing them from capitalizing on such virtuous circles associated with team cohesion. Yet, many teams uphold their performance despite the failures they have to cope with, suggesting that the potential vicious circles can be overcome. This chapter aims at illuminating the vicious and virtuous circles associated with team cohesion that are induced by either collective failures of teams or individual failures of their members. It therefore offers a multilevel perspective not only on the emergence and diffusion of failures at the individual and team levels, but also on the critical role that team cohesion plays for a team’s (dys)functional coping across these levels. It is theorized that collective failures triggered exogenously can help build team cohesion, and that whether endogenously-triggered collective failures bring about the vicious or the virtuous circles of team cohesion depends on whether the individual failures developing into collective failures are triggered endogenously or exogenously. The implications of this conceptual work are discussed in light of the literatures on error/failure management and group cohesiveness.

While economists are increasingly acknowledging the importance of distributional issues, the distribution of the consumption of food items has largely been neglected. The purpose of this paper is to demonstrate that important insights can be obtained by analysing the distribution of consumption of food products within society.

This study was conducted by analysing food consumption in two very different countries: Romania, a middle-income country and Switzerland, one of the most prosperous countries in the world. In order to test the formulated hypotheses, consumption per capita was calculated, as a base for the calculation of the Gini coefficient of consumption for each product. A mixed effect model was applied for total food and for meat, computing the predictors for the variable “consumption distribution”.

Using the Gini coefficients of food and drink item consumption by Romanian and Swiss households, the authors tested the hypothesis that in prosperous middle-income countries the homogeneity of food consumption is growing over time as a sign of consumption democratisation, whereas in high-income countries a growing degree of individualisation is leading to decreasing homogeneity. For meat, the bifurcation of consumption patterns between vegetarians and hedonists leads to a growing Gini coefficient over time for both countries. The analysis controls for factors such as the products’ importance in the diet and their price.

The paper approaches a new subject and raises a new research question that may be relevant for structural issues of contemporary society. Both the comparative analysis of food distribution in two different societies and their dynamics is a novelty.

This paper aims to address the numerical simulation of additive manufacturing (AM) processes. The numerical results are compared with the experimental campaign carried out at State Key Laboratory of Solidification Processing laboratories, where a laser solid forming machine, also referred to as laser engineered net shaping, is used to fabricate metal parts directly from computer-aided design models. Ti-6Al-4V metal powder is injected into the molten pool created by a focused, high-energy laser beam and a layer of added material is sinterized according to the laser scanning pattern specified by the user.

The numerical model adopts an apropos finite element (FE) activation technology, which reproduces the same scanning pattern set for the numerical control system of the AM machine. This consists of a complex sequence of polylines, used to define the contour of the component, and hatches patterns to fill the inner section. The full sequence is given through the common layer interface format, a standard format for different manufacturing processes such as rapid prototyping, shape metal deposition or machining processes, among others. The result is a layer-by-layer metal deposition which can be used to build-up complex structures for components such as turbine blades, aircraft stiffeners, cooling systems or medical implants, among others.

Ad hoc FE framework for the numerical simulation of the AM process by metal deposition is introduced. Description of the calibration procedure adopted is presented.

The objectives of this paper are twofold: firstly, this work is intended to calibrate the software for the numerical simulation of the AM process, to achieve high accuracy. Secondly, the sensitivity of the numerical model to the process parameters and modeling data is analyzed.

In this paper, after an elucidation of several central concepts of the topic, the author focuses on the sales channels in tourism and clarifies the role retailers play in the market. He shows that the existence of institutional travel retailers is generally based on transaction costs, and that thanks to the automation the level of dependence on transaction costs can be reduced. This thesis induces the question to what extent the retailers' performances can be automated. In answer to this question the author creates a list of criteria including the following aspects; the general and occasional suitability of retail products (e g tickets, travel packages), the availability of technical equipment and information necessary for the automation at the points of sale and in the households (buyers), the level of complexity and acceptance regarding the handling of automated travel services. The paper comes to the conclusion that the automation of travel services will probably be used mainly by business travelers, whereas private customers will more likely keep their affinity for conventional retailers.

Although still under-researched and characterized by a fragmented understanding, unlearning and forgetting have recently received increased scholarly attention. The purpose of this systematic literature review is to survey and evaluate key works in the field of organizational unlearning and forgetting. Through analyzing and synthesizing common themes, this paper aims to highlight research gaps and avenues for future research.

This paper follows a systematic approach of identifying, analyzing and synthesizing pertinent literature in the field of organizational unlearning and forgetting. In total, 63 works were thoroughly reviewed.

This paper highlights different levels and scopes, as well as antecedents and consequences of organizational unlearning and forgetting. Even though unlearning and forgetting has gained increased attention, researchers still need to provide robust conceptual and empirical evidence to advance the field.

By structuring the analysis and synthesis around various constructs, theories, typologies and related themes, this paper outlines several research gaps and proposes avenues for further research. Additionally, this systematic literature review resulted in the development of a framework based on the intentionality and depth of knowledge loss, which allows future researchers to position their research and differentiate themselves from other literature in the field.

During the powder bed fusion process, thermal distortion is one big problem owing to the thermal stress caused by the high cooling rate and temperature gradient. For the purpose of avoiding distortion caused by internal residual stresses, support structures are used in most selective laser melting (SLM) process especially for cantilever beams because they can assist the heat dissipation. Support structures can also help to hold the work piece in its place and reduce volume of the printing materials. The mitigation of high thermal gradients during the manufacturing process helps to reduce thermal distortion and thus alleviate cracking, curling, delamination and shrinkage. Therefore, this paper aims to study the displacement and residual stress evolution of SLMed parts.

The objective of this study was to examine and compare the distortion and residual stress properties of two cantilever structures, using both numerical and experimental methods. The part-scale finite element analysis modeling technique was applied to numerically analyze the overhang distortions, using the layer-by-layer model for predicting a part scale model. The validation experiments of these two samples were built in a SLM platform. Then average displacement of the four tip corners and residual stress on top surface of cantilever beams were tested to validate the model.

The validation experiments results of average displacement of the four tip corners and residual stress on top surface of cantilever beams were tested to validate the model. It was found that they matched well with each other. From displacement and residual stress standpoint, by introducing two different support structure, two samples with the same cantilever beam can be successfully printed. In terms of reducing wasted support materials, print time and high surface quality, sample with less support will need less post-processing and waste energy.

Numerical modeling in this work can be a very useful tool to parametrically study the feasibility of support structures of SLM parts in terms of residual stresses and deformations. It has the capability for fast prediction in the SLMed parts.