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In this paper, we focus on the quality of a 2D elastic finite element analysis.

Our objective is to control the discretization parameters in order to achieve a prescribed local quality level over a dimensioning zone. The method is based on the concept of constitutive relation error.

The method is illustrated through 2D test examples and shows clearly that in terms of cost, this technique provides an additional benefit compared to previous methods.

The saving would be even more significant if this mesh adaptation technique were applied in three dimensions. Indeed, in 3D problems, the computing cost is vital and, in general, it is this cost that sets the limits.

This tool is directly usable in the design stage.

The new tool developed guarantees a local quality level prescribed by the user.

This paper aims to focus on the local quality of outputs of interest computed by a finite element analysis in linear elasticity.

In particular outputs of interest are studied which do not depend linearly on the solution of the problem considered such as the L2‐norm of the stress and the von Mises' stress. The method is based on the concept of error in the constitutive relation.

The method is illustrated through 2D test examples and shows that the proposed error estimator leads in practice to upper bounds of the output of interest being studied.

This tool is directly usable in the design stage. It can be used to develop efficient adaptive techniques.

The interest of this paper is to provide an estimation of the local quality of L2‐norm of the stress and the Von Mises' stress as well as practical upper bounds for these quantities.

This paper aims to deal with the verification of local quantities of interest obtained through linear elastic finite element analysis. A technique is presented for determining the most accurate error estimation. This technique enables one to address industrial‐size problems while keeping computing costs reasonable.

The concept of error in constitutive relation is used to assess the quality of the finite element solution. The key issue is the construction of admissible fields. The objective is to show that it is possible to build admissible fields using a new method. These fields are obtained by using a high‐quality construction over a limited zone while the construction is less refined and less expensive elsewhere.

Numerical tests are presented in order to illustrate a very satisfying presented methodology. It shows clearly how to take advantage of the method to treat large examples. They clearly show the interest of this new method to treat large examples.

The paper demonstrates clearly that verification of large finite element problem must have dedicated methods in order to be applicable.

Traditional adaptive analysis based on a coarse mesh, using finite element method (FEM) analysis, produces the original solution. Then post-processing the result and figuring out the regions should be refined and these regions refined once. Finally, this new mesh is used to get the solution of first refinement. After several iterations of above procedures, we can achieve the last result that is closer to the true solution, which takes time, making adaptive scheme inpractical to engineering application. The paper aims to discuss these issues.

This paper based on FEM proposes a multi-level refinement strategy with a refinement strategy and an indicator. The proposed indicator uses value of the maximum difference of strain energy density among the elements that associated with one node, and divides all nodes into several categories based on the value. A multi-level refinement strategy is proposed according to which category the node belongs to refine different elements to different times rather than whether refine or not.

Multi-level refinement strategy takes full use of the numerical calculation, resulting in the whole adaptive analysis that only need to iterate twice while other schemes must iterate more times. Using much less times of numerical calculation and approaches, more accurate solution, making adaptive analysis more practical to engineering.

Multi-level refinement strategy takes full use of the numerical calculation, resulting in the whole adaptive analysis only need iterate twice while other schemes must iterate more times. using much less times of numerical calculation and approaches more accurate solution, making adaptive analysis more practical to engineering.

The first problem is to assemble the works of Pucci; for there is no complete edition. His writings, some still unpublished, are scattered in a large number of manuscripts and these contain many variants, resulting from the popular nature of his verse, for much of it was meant to be recited in the streets and squares of his native town and in the oral tradition it has been considerably changed and modified. The Pucci manuscripts, with the exception of four (one in the Bibliothèque Nationale and three in the Bodleian), are to be found in various libraries in Italy, and editors and compilers of anthologies have taken material from them—a bit here and a bit there—in a haphazard way, printing what suited their purpose and often consulting only one of many manuscripts. Consequently there are different versions of some poems and few are edited critically, though the publication last year of Professor Sapegno's anthology Poeti minori del trecento with its 117 pages devoted to Pucci has remedied this state of affairs for some of the most important. The only collection of Pucci's verse—if we discount a group of sonnets and a sonnet sequence, both published by A. D'Ancona—is that of F. Ferri in La poesia popolare in A. Pucci (1909), and this is a very incomplete and uncritical work; but as it includes many poems not found elsewhere, it is essential for reference. Pucci's work in print must therefore be sought in many places: in F. Ferri (op. cit.), in anthologies, in periodicals, in editions of single or of two or three poems, and in many rare publications—often per nozze and therefore particularly difficult to come by, because of the few copies printed.

The purpose of this paper is to acquire strict upper and lower bounds on quantities of slender beams on Winkler foundation in finite element analysis.

It leans on the dual analysis wherein the constitutive relation error (CRE) is used to perform goal-oriented error estimation. Due to the coupling of the displacement field and the stress field in the equilibrium equations of the beam, the prolongation condition for the stress field which is the key ingredient of CRE estimation is not directly applicable. To circumvent this difficulty, an approximate problem and the solution thereof are introduced, enabling the CRE estimation to proceed. It is shown that the strict bounding property for CRE estimation is preserved and strict bounds of quantities of the beam are obtainable thereafter.

Numerical examples are presented to validate the strict upper and lower bounds for quantities of beams on elastic foundation by dual analysis.

This paper deals with one-dimensional (1D) beams on Winkler foundation. Nevertheless, the present work can be naturally extended to analysis of shells and 2D and 3D reaction-diffusion problems for future research.

CRE estimation is extended to analysis of beams on elastic foundation by a decoupling strategy; strict upper bounds of global energy norm error for beams on elastic foundation are obtained; strict bounds of quantities for beams on elastic foundation are also obtained; unified representation and corresponding dual analysis of various quantities of the beam are presented; rigorous derivation of admissible stresses for beams is given.

Recent years have seen a technological change, Industry 4.0, in the manufacturing industry. Human–robot cooperation, a new application, is increasing and facilitating collaboration without fences, cages or any kind of separation. The purpose of the paper is to review mainstream academic publications to evaluate the current status of human–robot cooperation and identify potential areas of further research.

A systematic literature review is offered that searches, appraises, synthetizes and analyses relevant works.

The authors report the prevailing status of human–robot collaboration, human factors, complexity/ programming, safety, collision avoidance, instructing the robot system and other aspects of human–robot collaboration.

This paper identifies new directions and potential research in practice of human–robot collaboration, such as measuring the degree of collaboration, integrating human–robot cooperation into teamwork theories, effective functional relocation of the robot and product design for human robot collaboration.

This paper will be useful for three cohorts of readers, namely, the manufacturers who require a baseline for development and deployment of robots; users of robots-seeking manufacturing advantage and researchers looking for new directions for further exploration of human–machine collaboration.

While concentration of population in urban areas continues, limited contact with ecological dynamics undermines awareness on human dependence on ecosystems. However, demands on ecosystems have never been higher than in today's urbanized planet, and cities make major contributions to global environmental problems. Enhancing green and blue infrastructure (GBI) in cities can reduce the ecological footprints of cities, while enhancing urban resilience and quality of life for their inhabitants. Urban GBIs provide multiple benefits to people in the form of ecosystem services (ES) and hold potential for providing nature-based solutions (NBS) to address urban challenges.

To adequately evaluate the ES provided by GBI, researchers have recently advocated integrated valuations. Integrated valuations aim at overcoming the limitations of the traditional single discipline and narrow approaches, by considering the multiple ways in which humans benefit from nature across the economic social and cultural domains.

In this chapter, we present examples of integrated valuations of ES in two Spanish cities, Barcelona and Bilbao. Both examples combine different valuation techniques and metrics, both monetary and nonmonetary, to account for the ES provided by urban GBIs and to assess their potential as NBS.

Our case examples show that urban GBIs provide many valuable benefits to urban dwellers. One of the clearest outcomes from these infrastructures is cultural ES, especially the multiple recreation and leisure opportunities they provide, which in turn has a remarkable positive effect on human health and well-being.

This paper aims to describe how a sustainability-focused program in higher education can provide training and key experiences for implementing transdisciplinary approaches. The case is a fieldwork-based training course called the Global Field Exercise (GFE) at the Graduate Program in Sustainability Science, The University of Tokyo. The GFE is a methodological training course that emphasizes generating locally relevant research questions on sustainability.

This research is a case study regarding how a sustainability science program can offer a fieldwork-based training course that focuses on a transdisciplinary approach. Five students from diverse academic disciplines and cultural backgrounds participated in the GFE in QwaQwa where they conducted semi-structured interviews with six local entrepreneurs to identify the challenges and opportunities of entrepreneurship. The authors investigated the learning process and outcomes of the students through participatory observation in preparatory meetings, daily reflection sessions during fieldwork and a content analysis of feedback reports.

Four learning outcomes of the students were suggested: the reexamination of assumptions, managing misunderstanding and miscommunication, mutual learning and being empathic toward the local people.

This paper suggests three key opportunistic experiences for the transdisciplinary approach: discuss the normative dimension of sustainability; build intersubjectivity among team members and adopt methodological pluralism; and become empathetic to diverse stakeholder groups to facilitate the cogeneration of knowledge.

How to design training on a transdisciplinary approach in educational programs remains an area for further exploration. This study addresses this knowledge gap by establishing a link between sustainability education and sustainability in practice.

The purpose of this paper is to apply virtual agonist–antagonist mechanisms (VAAMs) to robot joint control allowing for muscle-like functions and variably compliant joint motions. Biological muscles of animals have a surprising variety of functions, i.e. struts, springs and brakes.

Each joint is driven by a pair of VAAMs (i.e. passive components). The muscle-like functions as well as the variable joint compliance are simply achieved by tuning the damping coefficient of the VAAM.

With the VAAM, variably compliant joint motions can be produced without mechanically bulky and complex mechanisms or complex force/toque sensing at each joint. Moreover, through tuning the damping coefficient of the VAAM, the functions of the VAAM are comparable to biological muscles.

The model (i.e. VAAM) provides a way forward to emulate muscle-like functions that are comparable to those found in physiological experiments of biological muscles. Based on these muscle-like functions, the robotic joints can easily achieve variable compliance that does not require complex physical components or torque sensing systems, thereby capable of implementing the model on small-legged robots driven by, for example, standard servo motors. Thus, the VAAM minimizes hardware and reduces system complexity. From this point of view, the model opens up another way of simulating muscle behaviors on artificial machines.

The VAAM can be applied to produce variable compliant motions of a high degree-of-freedom robot. Only relying on force sensing at the end effector, this application is easily achieved by changing coefficients of the VAAM. Therefore, the VAAM can reduce economic cost on mechanical and sensing components of the robot, compared to traditional methods (e.g. artificial muscles).