Ergonomic factors and production target evaluation in eucalyptus timber harvesting operations in mountainous terrains

There are several forest operations involved in Eucalyptus timber harvesting. This study was carried out during brush-cutting; tree felling, bucking, delimbing, piling and manual extraction operations, with the following objectives: a) analyzing, ergonomically, two systems of brush-cutting: one manual and the other semi-mechanized, using two different machines; b) ergonomically evaluating three different brands of pruner machines used in delimbing felled trees. c) determining the feasible target of productivity as a function of ergonomic factors relevant to establish the time of resting pauses for workers in manual and semi-mechanized timber harvesting systems in mountainous terrain. Brush-cutting, either manual or semimechanized, is an activity carried out prior to timber harvesting. It is usually a hard work, with low productivity when compared with mechanized systems. Pruner machines have been used by forest companies, due to the great possibilities to improve productivity, quality and the health of workers. Ergonomics is a discipline that promotes the adequacy of work to the physical and mental characteristics of human beings, seeking to design production systems and products considering relevant aspects, including social, organizational and environmental factors. Companies should consider the ergonomic factor in the determination of daily worker production targets.     

How Moroccan‐Dutch parents learn in communities of practice: Evaluating a bottom‐up parenting programme

Research shows that top‐down‐designed parenting programmes do not always meet the needs of postmigration parents. Bottom‐up programmes by migrant organizations hold a promise to fill this gap; however, research about these programmes and appropriate evaluation methodologies is scarce. Drawing upon Wenger's ( 2010 ) “communities of practice,” this paper explores an alternative perspective on parenting programme evaluation. Findings are presented from a study looking into social learning processes of postmigration parents who participated in a bottom‐up programme about raising teenagers in urban areas. Using an ethnographically inspired method combined with a preprogramme and postprogramme design, 115 Moroccan‐Dutch mothers and fathers from 15 programme groups participated. Results show that the programme provided a social learning space in which parents used themselves as resources to learn collectively about parenting. Moreover, parents consciously engaged in learning interactions across learning spaces stretched into their social networks. These analyses showed how parents' development of “learning citizenship” (Wenger, 2009 ) provides us with insight in collective learning dimensions present in a bottom‐up parenting programme, which is often not included in evaluation studies. Implications for practitioners as facilitators of parents' collective learning are presented.     

Multivariate log-skewed distributions with normal kernel and their applications

We introduce two classes of multivariate log-skewed distributions with normal kernel: the log canonical fundamental skew-normal (log-CFUSN) and the log unified skew-normal. We also discuss some properties of the log-CFUSN family of distributions. These new classes of log-skewed distributions include the log-normal and multivariate log-skew normal families as particular cases. We discuss some issues related to Bayesian inference in the log-CFUSN family of distributions, mainly we focus on how to model the prior uncertainty about the skewing parameter. Based on the stochastic representation of the log-CFUSN family, we propose a data augmentation strategy for sampling from the posterior distributions. This proposed family is used to analyse the US national monthly precipitation data. We conclude that a high-dimensional skewing function lead to a better model fit.     

Psychosocial Factors of Migration: Adaptation and Application of the Health Belief Model

Psychosocial factors influencing behaviour play a central role in health research but seem under‐explored in migration research. This is unfortunate because these factors, which include knowledge, attitudes, beliefs, intentions and personality traits, provide essential and potentially effective handles for linking migration and migrant‐integration policies. We demonstrate that the health belief model (HBM) conceptualization of behavioural intentions contributes constructs that can further our understanding of migration intentions, thereby broadening the foundations for migration policies. We adapt the HBM to migration behaviour and then test it empirically by using survey data on international migration from West Africa and the Mediterranean region to the European Union. The results confirm that indicators of “perceived threat to living conditions”, “perceived benefits” and “perceived barriers to migration”, “cues to action” and “self‐efficacy” contribute considerably to the explanation of migration intentions. We conclude that psychosocial factors deserve greater prominence in migration theories and empirical research, and we recommend that migration surveys consider this framework to identify relevant indicators of psychosocial factors of international migration and develop appropriate survey questions to measure them.     

Relationships of Online Social Comparison and Parenting Satisfaction among New Mothers: The Mediating Roles of Belonging and Emotion

New mothers frequently seek information and community on social networking sites as they seek to establish their parenting practices. As social networking sites for mothers (SNSM) present an environmental influence on the family system, a mother’s experience with social comparison, belonging, and emotion on SNSM can bear significant influence over her satisfaction with her parenting. The present study utilized survey methods to explore mothers’ (n= 336) reported experiences of these variables. We use structural equation modeling to specify a model with good fit, which indicated that greater downward comparison directly related to greater parenting satisfaction, with belonging and negative emotion as mediating indirect relationships. Implications for family communication and mothers’ SNSM practices are discussed.     

Fast parallel $$\alpha $$-stable distribution function evaluation and parameter estimation using OpenCL in GPGPUs

\(\alpha \)-Stable distributions are a family of probability distributions found to be suitable to model many complex processes and phenomena in several research fields, such as medicine, physics, finance and networking, among others. However, the lack of closed expressions makes their evaluation analytically intractable, and alternative approaches are computationally expensive. Existing numerical programs are not fast enough for certain applications and do not make use of the parallel power of general purpose graphic processing units. In this paper, we develop novel parallel algorithms for the probability density function and cumulative distribution function—including a parallel Gauss–Kronrod quadrature—, quantile function, random number generator and maximum likelihood estimation of \(\alpha \)-stable distributions using OpenCL, achieving significant speedups and precision in all cases. Thanks to the use of OpenCL, we also evaluate the results of our library with different GPU architectures.     

Distractions N' Driving: video game simulation educates young drivers on the dangers of texting while driving

The proliferation of portable communication and entertainment devices has introduced new dangers to the driving environment, particularly for young and inexperienced drivers. Graduate students from George Mason University illustrate a powerful, practical, and cost-effective program that has been successful in educating these drivers on the dangers of texting while driving, which can easily be adapted and implemented in other communities.     

The Meaning of Trust for Brazilians with Higher Education

The validity of the World Values Survey (WVS) question used to measure trust is disputed over and this article is intended to present the results of an online survey, conducted in Brazil, which tested the meaning of the term trust in the WVS question. The surveyed population is entirely Brazilian and the majority has received some form of higher education. The results of the survey partially corroborate the validity of the WVS and partially deny it. Within the results of this survey there are predominantly two dominant perspectives represented within the surveyed population including: respondents who think in friends and relatives as part of most people have a higher probability of also saying to trust most people which means that different people may be answering slightly different questions. However, respondents who say that trust most people have higher levels of trust in people in general than in family if compared with respondents who say to not trust most people which is in accordance with the expectation that the question adequately measures generalized interpersonal trust.     

Analysis on the relationship between the school furniture and the work surface lighting and the body posture of public Middle School students from João Pessoa, Paraíba, Brazil

The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of two public Middle School students from Paraíba (Brazil). The target population included 8th grade groups involving 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck and about 90% of the students presented postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints.