P.A.J. VAN DEN BOGERT, R. DE BORST, G.T. LUITEN and J. ZEILMAKER
A marked characteristic of rubber‐like materials is the nearly incompressible behaviour. This type of behaviour is best modelled by mixed finite elements with separate…
Abstract
A marked characteristic of rubber‐like materials is the nearly incompressible behaviour. This type of behaviour is best modelled by mixed finite elements with separate interpolation functions for the displacements and the pressure. In this contribution the performance of three‐dimensional elements is investigated using a two‐tiered strategy. First, the ability of some linear and quadratic three‐dimensional elements to deform correctly under nearly isochoric conditions is estimated using the well‐known constraint‐counting method, in which the ratio of the number of degrees‐of‐freedom over the number of kinematic constraints present in the finite element mesh is determined. Next, the performance of the elements is assessed by numerical simulations for three cuboidal rubber blocks with different shape factors. The results turn out to be quite sensitive with respect to the ratio of the number of degrees‐of‐freedom over the number of kinematic constraints, since too many pressure degrees‐of‐freedom make the element overstiff, while too few pressure degrees‐of‐freedom may cause the occurrence of spurious kinematic modes. This observation appears to be not only valid for the global structural behaviour, but also with respect to the specific parts in the structure, where the above‐mentioned ratio is different from the global number, e.g., in corners of the structure.
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M. Kaliske and H. Rothert
Derives a formulation for spatial stress tensors and spatial material tensors of hyperelastic material. Looks at a class of materials with the strain energy function decomposed…
Abstract
Derives a formulation for spatial stress tensors and spatial material tensors of hyperelastic material. Looks at a class of materials with the strain energy function decomposed into a volumetric and a deviatoric part. Separate terms formulate the strain energy with respect to the invariants of the left Cauchy‐Green tensor. Stress and material tensors, which play a crucial role in the solution process of the finite element formulation, are derived solely in the current configuration. Applies the described framework to several different constitutive models based on phenomenologically and physically motivated material descriptions. Proposes a formulation for the finite element implementation of van der Waals material. Compares numerical results with experimental investigations given in the literature. For three‐dimensional finite element computations standard elements and mixed elements, based on a three‐field variational principle where displacements, the hydrostatic pressure and the dilatations are independent variables, are used.
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Katie Andrews, Noemi Sinkovics and Rudolf R. Sinkovics
This chapter investigates the coffee value chain in Latin America. By drawing on the concept of just transitions as a “connective tissue” between the sustainable development goals…
Abstract
This chapter investigates the coffee value chain in Latin America. By drawing on the concept of just transitions as a “connective tissue” between the sustainable development goals (SDGs), the discussion zooms in on the promise of agroforestry for environmental upgrading. The chapter concludes by providing examples of trade-offs between environmental, social and economic aspects.
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Sarah Carpentier, Karel Neels and Karel Van den Bosch
The administration of social assistance benefits is devolved to local agencies in Belgium, which raises questions about how much variation in spell lengths of benefit receipt is…
Abstract
The administration of social assistance benefits is devolved to local agencies in Belgium, which raises questions about how much variation in spell lengths of benefit receipt is associated with differences across agencies. We address this issue by analysing the monthly hazard of benefit exit using administrative record data for 14,270 individuals in 574 welfare agencies. Our random-effects model allows for differences in both the observed and unobserved characteristics of beneficiaries and of local agencies. There are large differences in median benefit duration for individuals serviced by different welfare agencies: the range is from two months to more than 24 months. We find strong associations between beneficiary characteristics (sex, age, foreign nationality, citizenship acquisition, work history and being a student) and spell length. The estimates show higher odds of exiting social assistance receipt in bigger municipalities and in agencies which provide more generous supplementary assistance, and also strong evidence of shorter episodes in agencies where active labour market programme participation rates are higher.
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Paul Ter Horst, Marinus Spreen and Stefan Bogaerts
This paper aims to illustrate by means of a case study how HKT-R Spider reference profiles of recidivists and non-recidivists may be supportive in leave decisions.
Abstract
Purpose
This paper aims to illustrate by means of a case study how HKT-R Spider reference profiles of recidivists and non-recidivists may be supportive in leave decisions.
Design/methodology/approach
The authors describe what is known for recidivists and non-recidivists about changes in risk factors during treatment. The HKT-R Spider is introduced. By comparing a case study to group profiles, the authors illustrate how discussions about leave may be rationalised. From a study among 278 patients to explore the profiles, the authors report the inter agreement, and differences between recidivists and non-recidivists of the clinical HKT-R factors. Intra correlation coefficients, Wilcoxon signed ranks test and independent and paired t-tests are applied. To explore which combination of factors are discriminating between both groups, the authors also performed logistic regression analyses at six treatment stages.
Findings
The inter agreement reliability and internal consistency of the clinical HKT-R scale were acceptable to good in all six stages studied. The HKT-R Spider and profiles can be used to assist in evidence-informed decision-making about leave.
Practical implications
Globally recidivists had somewhat higher levels of clinical risk factors at all six decision moments, but the interpretation of HKT-R Spiders profiles should always be adapted to the individual’s context.
Originality/value
Applying the HKT-R Spider reference profiles on individual cases may structure and rationalize discussions lead to decisions based on clinical facts.
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Catarina Tomé Pires, Genta Kulari, Luísa Ribeiro and Tito Laneiro
This paper aims to explore how nurses stay engaged in their work with the impact of structural empowerment and civility. It delves deeper into how kind, empathetic and respectful…
Abstract
Purpose
This paper aims to explore how nurses stay engaged in their work with the impact of structural empowerment and civility. It delves deeper into how kind, empathetic and respectful behaviours (civility) among colleagues influence the link between structural empowerment and nurses’ engagement.
Design/methodology/approach
Data was collected from 580 nurses working in a Public Hospital in the metropolitan area of Lisbon. Self-report questionnaires measuring civility, structural empowerment and engagement were administered. Hayes’ PROCESS macro for mediation analysis in SPSS was used to test the hypothesised model.
Findings
Results demonstrated that civility and structural empowerment were positively associated (r = 0.491, p < 0.01) also showing a positive influence on nurses’ engagement (r = 0.492, p < 0.01; r = 0.485, p < 0.01, respectively). Civility was found to partially mediate the association between structural empowerment and engagement (ß = 0.315, 95% CI [0.222, 0.417], 5,000 bootstrap resamples).
Practical implications
Findings from this study may be used for health-care employees and organisations, implying that when nurses perceive themselves as structurally empowered at work within a respectful environment, they experience an enhanced sense of community and involvement in their organization.
Originality/value
To the best of the authors’ knowledge, this is the first attempt in exploring the relationship of combined workplace civility, structural empowerment and engagement in a sample of Portuguese nurses. Future research could substantially increase our understanding of how civility contributes to a positive workplace.
Propósito
Este artículo explora cómo las enfermeras se mantienen comprometidas (work engagement) en su trabajo con el impacto del empoderamiento estructural y la civilidad. Profundiza en cómo los comportamientos amables, empáticos y respetuosos (civilidad) entre colegas influyen en el vínculo entre el empoderamiento estructural y el work engagement de las enfermeras/os.
Diseño/metodología/enfoque
Se recogieron datos de 580 enfermeras que trabajaban en un hospital público del área metropolitana de Lisboa. Se administraron cuestionarios de autoinforme que medían la civilidad, el empoderamiento estructural y el work engagement. Se utilizó la macro PROCESS de Hayes para el análisis de mediación en SPSS con el fin de probar el modelo hipotetizado.
Resultados
Los resultados demostraron que la civilidad y el empoderamiento estructural estaban positivamente asociados (r = 0.491, p < 0.01) mostrando también una influencia positiva en el work engagement de las enfermeras (r = 0.492, p < 0.01; r = 0.485, p < 0.01, respectivamente). Se observó que la civilidad mediaba parcialmente la asociación entre el empoderamiento estructural y el work engagement (β = 0.315, 95% CI [0.222, 0.417], 5,000 resamples bootstrap).
Implicaciones prácticas
Los resultados de este estudio pueden ser utilizados por los empleados y las organizaciones sanitarias, ya que implican que cuando las enfermeras se perciben a sí mismas como estructuralmente empoderadas en el trabajo dentro de un entorno respetuoso, experimentan un mayor sentido de comunidad e implicación en su organización.
Originalidad/valor
Hasta donde sabemos, este es el primer intento de explorar la relación entre la civilidad en el lugar de trabajo, el empoderamiento estructural y el work engagement en una muestra de enfermeras portuguesas. Futuras investigaciones podrían aumentar sustancialmente nuestra comprensión de cómo el civismo contribuye a un lugar de trabajo positivo.
Propósito
Este documento explora a forma como os enfermeiras/os se mantêm empenhados e envolvidos (work engagement) no seu trabalho, tendo em conta o impacto do empoderamento estrutural e da civilidade. Aprofunda a forma como os comportamentos de gentileza, empatia e respeito (civilidade) entre colegas influenciam a relação entre o empoderamento estrutural e o work engagement dos enfermeiros.
Desenho/metodologia/abordagem
Foram recolhidos dados de 580 enfermeiros de um Hospital Público da área metropolitana de Lisboa. Foram aplicados questionários de auto-relato para avaliar a civilidade, o empoderamento estrutural e o work engagement. A macro PROCESS de Hayes para análise de mediação no SPSS foi utilizada para testar o modelo hipotético.
Resultados
Os resultados demonstraram que a civilidade e o empoderamento estrutural estavam positivamente associados (r = 0.491, p < 0.01), mostrando também uma influência positiva no work engagement dos enfermeiros (r = 0.492, p < 0.01; r = 0.485, p < 0.01, respetivamente). Verificou-se que a civilidade medeia, parcialmente, a associação entre a empoderamento estrutural e o work engagement (β = 0.315, 95% CI [0.222, 0.417], 5,000 resamples bootstrap).
Implicações práticas
Os resultados deste estudo podem ser uteis para os trabalhadores e organizações de cuidados de saúde, implicando que, quando os enfermeiros se consideram estruturalmente capacitados no trabalho num ambiente de respeito, experimentam um maior sentido de comunidade e envolvimento na sua organização.
Originalidade/valor
Até à data, esta é a primeira tentativa de explorar a relação entre civilidade no local de trabalho, empoderamento estrutural e work engagement numa amostra de enfermeiros portugueses. Futuras investigações poderão aumentar substancialmente a nossa compreensão de como a civilidade contribui para um ambiente laboral positivo.
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C.H. Liu, G. Hofstetter and H.A. Mang
The paper starts with a review of constitutive equations forrubber‐like materials, formulated in the invariants of the rightCauchy—Green deformation tensor. A general framework…
Abstract
The paper starts with a review of constitutive equations for rubber‐like materials, formulated in the invariants of the right Cauchy—Green deformation tensor. A general framework for the derivation of the stress tensor and the tangent moduli for invariant‐based models, for both the reference and the current configuration, is presented. The free energy of incompressible rubber‐like materials is extended to a compressible formulation by adding the volumetric part of the free energy. In order to overcome numerical problems encountered with displacement‐based finite element formulations for nearly incompressible materials, three‐dimensional finite elements, based on a penalty‐type formulation, are proposed. They are characterized by applying reduced integration to the volumetric parts of the tangent stiffness matrix and the pressure‐related parts of the internal force vector only. Moreover, hybrid finite elements are proposed. They are based on a three‐field variational principle, characterized by treating the displacements, the dilatation and the hydrostatic pressure as independent variables. Subsequently, this formulation is reduced to a generalized displacement formulation. In the numerical study these formulations are evaluated. The results obtained are compared with numerical results available in the literature. In addition, the proposed formulations are applied to 3D finite element analysis of an automobile tyre. The computed results are compared with experimental data.
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Michele Schmitter, Jeroen Vermunt, Eric Blaauw and Stefan Bogaerts
Given the complex association between substance use disorders (SUD), comorbid mental health problems and criminal recidivism in forensic patients, homogenous patient classes can…
Abstract
Purpose
Given the complex association between substance use disorders (SUD), comorbid mental health problems and criminal recidivism in forensic patients, homogenous patient classes can contribute to a refined treatment. This paper aims to construct those classes in forensic patients (N = 286) diagnosed with SUD, unconditionally released between 2004 and 2013 of one of ten Dutch forensic psychiatric centers.
Design/methodology/approach
Retrospective data were derived from electronic patient files. Classes were based on the Dutch risk assessment tool, the Historisch Klinisch Toekomst-Revisie (Historical Clinical Future–Revised [HKT-R]) and identified by means of explorative Latent Class Analysis in Latent Gold version 5.1. In a three-step approach, posterior class memberships were related to external variables (i.e. diagnoses, type of drug and type of offence).
Findings
Four classes were identified that differ in the risk of recidivism, as well as Axis I and II diagnoses and type of drug consumption.
Practical implications
This study informed on the heterogeneity of forensic patients with SUD and identified four homogenous classes that differ in important variables for the treatment approach. Based on these classes, a more refined treatment approach can be developed. Possible treatment approaches are discussed, but future research is needed to provide evidence.
Originality/value
This study is the first to identify classes within forensic patients with SUD and, therefore, sets the first step to develop a tailored treatment approach based on characteristics informative for treatment.
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Nina Geuens, Erik Franck, Peter Vlerick and Peter Van Bogaert
Preventing burnout and promoting psychological well-being in nurses are of great importance. In this study the effect of an online, stand-alone individualized preventive program…
Abstract
Purpose
Preventing burnout and promoting psychological well-being in nurses are of great importance. In this study the effect of an online, stand-alone individualized preventive program for nurse burnout based on cognitive behavioral therapy (CBT) is described and explained.
Design/methodology/approach
A mixed method study with an explanatory sequential design was applied. Quantitative data were collected from September 2015 to March 2016 during an intervention study with a pretest-posttest wait-list control group design within a population of hospital nurses in the Dutch speaking part of Belgium. Consecutively, 13 nurses from the intervention group who fully completed the program were interviewed.
Findings
All interviewed participants experienced some sort of effect due to working with the program. Emotional exhaustion remained stable in the intervention group and increased in the control group. However, this difference was not significant. Personal accomplishment decreased significantly within the intervention group when compared to the control group. This might be explained by the self-awareness that was created through the program, which confronted participants with their weaknesses and problems.
Originality/value
This study adds to the understanding of online individual burnout prevention. The results suggest the feasibility of an online program to prevent nurse burnout. This could be optimized by complementing it with organizational interventions, introducing refresher courses, reminders and follow-up. Furthermore, additional attention should be devoted to preparing the implementation in order to minimize attrition rates.