Abstract
This paper addresses a two-dimensional (2D) non-guillotine cutting problem, where a set of small rectangular items of given types has to be cut from a large rectangular stock plate having defective regions so as to maximize the total value of the rectangles cut. The number of small items of each item type which can be cut from the large object is unrestricted. A novel MIP model and a hybrid approach combining a novel placement procedure with a biased random-key genetic algorithm (BRKGA) are presented. The parameters used by the novel placement procedure for the development of a cutting plan are evolved by the BRKGA. The management of the free spaces and of the defects uses a maximal-space representation. The approach is evaluated and compared to other approaches by means of a series of detailed numerical experiments using 5414 benchmark instances taken from the literature. The experimental results validate the quality of the solutions and the effectiveness of the proposed algorithm.

Abstract

Abstract
Purpose The purpose of this paper is to research the way in which Lean practices are affecting the performance of manufacturing small and medium enterprises (SMEs), analyzing the effects of Lean practices on companies' operational, financial and market performance. Design/methodology/approach An online questionnaire was distributed among Portuguese organizations that fitted the category of SMEs and belonged to the manufacturing sector. A sample of 329 enterprises was analyzed with partial least squares-structural equation modelling. Four hypotheses on the impact of Lean practices on company performance were tested. Findings The results show that the effects of Lean on performance are positive, which stresses the benefits attainable with the implementation of Lean practices. The aggregated implementation of Lean practices, namely, customer involvement, statistical process, continuous flow and total productive maintenance leads to improvements in company's global performance measured by market, financial and operational performance measures, and also improves each of these performance measures individually. It was also noticed that financial capability is one of the indispensable factors for the successful implementation of Lean practices. Originality/value This is the first study that examines the impact of the effect of Lean on operational, financial and market performance in a discriminated and simultaneous way.

Abstract
Onshore wind energy (WE) has achieved a significant diffusion worldwide, in spite of the existence of multiple barriers to the large-scale implementation of wind farms. These barriers have been reported in a large number of studies, but the literature is lacking a systematized overview of their categories and locations. Based on a framework for the analysis of barriers to the penetration of renewable energy sources proposed by Painuly [363], this systematic literature review contributes to addressing this gap, identifying barriers to the large-scale implementation of onshore wind farms by category (market failures, market distortions, economic and financial, institutional, technical, social and other barriers) and location (countries around the world), and characterizing them by the level of economic development (least developed, developing, in transition, and developed) and stage of diffusion (recent or advanced) in their locations. The framework showed a high level of fit with the case of WE and allowed the identification of 31 barriers in 159 countries. The barriers were found to be mostly present in developing economies with recent diffusion, although some barriers were found to occur broadly across developed economies, regardless of the stage of diffusion. The three most frequently observed barriers were the inadequate consideration of externalities, uncertain and unsupportive governmental policies, and insufficient transmission grids.

Abstract
The use of robots in rehabilitation attempts an effective, compliant, and time-efficient gait recovery while adapting the assistance to the user's needs. Assist-as-needed strategies (AAN), such as adaptive impedance control, have been reported as prominent strategies to enable this recovery effects. This study proposes an interaction-based assist-as-needed impedance control strategy for an ankle robotic orthosis that adapts the robotic assistance by changing the Human-Robot interaction stiffness. The adaptability of the interaction stiffness allows the real-time passage from passive assistance to an active one, approaching AAN gait training. The interaction stiffness was successfully estimated by linear regression of the Human-Robot interaction torque vs angle trajectory curve. From the validation with seven able-bodied subjects, we verified the suitability of this adaptive impedance control for a more compliant, natural, and comfortable motion than the trajectory tracking control. Moreover, the proposed strategy considers the users' motion intention and encourages them to interact closely with the robotic device while guiding their ankle trajectory according to desired trajectories. These achievements contribute to AAN gait training.

Abstract
This study identified and characterized the factors influencing managers' intentions to adopt collaborative robots (cobots) in manufacturing companies. Based on a conceptual framework that integrates three technology adoption theories (Diffusion of Innovation, Technology-organization-environment and Institutional theory) and following an exploratory qualitative research design, this paper identifies 39 factors influencing the intention to adopt cobots in three contexts (internal, external and technology). Twelve of these factors are new as contrasted with previous literature. The findings of this study can assist organizations in their process of adoption of cobots and in the development of managerial practices that consider the role of these factors.