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11.
Due to the increase of production costs in manual harvesting, strategies must be developed in order to overcome these effects, such as the attempts in implementing agricultural machines in harvest activities, whether being totally or partially mechanized. This study brings a qualitative and quantitative comparison on the impacts in work conditions and productivity in Brazilian orchards caused by the use of semi-mechanized harvesting systems, such as multiplatforms. The results come from the application of Ergonomic Work Analysis method, which focuses in the activity, quantifying and analyzing times and frequencies of the harvesting cycle, as well as the amount of movements. To achieve this, footage, interviews and a stopwatch were used in the observation 12 pickers' work cycles, six for each method of harvesting. The data interpretation pointed to improvement in working conditions with a reduction in the amount of movements performed by the picker, and increase of up to 60% in productivity with the use of semi-mechanized harvesting. Thus, the found results indicate the viability of this harvesting method. However, other variables must be observed in future studies in order to complete the guidelines for a healthy progress in the area of citrus harvesting in Brazil.  相似文献   
12.
This paper explores the importance of researching the intuitiveness in the product use. It approaches the intuitiveness influence for users that already had a visual experience of the product. Finally, it is suggested the use of a table that relates the tasks performed while using a product, the features for an intuitive use and the performance metric "task success".  相似文献   
13.
We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.  相似文献   
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Recent theorizations of affect have focused largely on Western historical, political and aesthetic contexts to distinguish between affect and emotion. Notably, these interventions offer new imaginaries to reinvigorate analysis of politics in the face of shrinking possibilities. However, much of this literature views affect as autonomous from emotion, while overlooking the political history of development and the differentiated relation to affect under colonial capitalism in other historical contexts. This paper studies subaltern engagement in activist performance in India to address these issues. It thinks through Lauren Berlant's account of the aesthetic genre and affective structure of cruel optimism, and her focus on historical contexts where people have recently lost the vision of a good life. By contrast, focusing on the historical present of those born into a pervasive and intractable sense of marginality and insecurity, I ask: what is the subject's relation to affect and activism in contexts where the loss of vision of a good life is not new under neoliberalism, but rather, reworks long-standing violence and inclusion/exclusion of colonial capitalism and nation-state histories. I argue that it is useful to understand Berlant's ‘materialist context for affect theory’ in light of uneven global histories of colonialism, development and neoliberalism. The affective experience of time is different across different spaces. As such, this paper contributes a global materialist context for affect theory, by focusing on activist theatre by a tribe called Chhara, designated ‘born criminals’ by British colonial law – a status legally denotified in 1952, but that is practically still effective in postcolonial India. Competing affective structures – sentimental optimism, cruel pessimism, betrayal and ordinary regard – shape and are shaped by Chhara negotiations with branded criminality. Ultimately, for the postcolonial subject, surviving in the neoliberal present involves vacillating among competing affective structures, only some of which generate sustained political critique.  相似文献   
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Job insecurity has received growing attention from researchers because it poses serious challenges for organisations and for society as a whole. However, there are insufficient studies about the processes through which job insecurity affects outcomes as well as potential ways to reduce its negative impact. This study focuses on the relationship between job insecurity and individual-level outcomes (in-role performance and organisational deviance) and examines if (a) job insecurity is positively and/or negatively related to work outcomes, (b) psychological contract breach acts as a mediator of the relationship between job insecurity and work outcomes, and (c) positive psychological capital (PsyCap) buffers the job insecurity–work outcomes relationship via psychological contract breach. With a sample of 362 employee–supervisor dyads, in which the outcome measures were collected from the supervisors, we found support for our hypotheses. Specifically, we found a moderated mediation effect, whereby PsyCap moderates the negative indirect relationship of job insecurity on outcomes through psychological contract breach.  相似文献   
18.
The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection.  相似文献   
19.
Governments in Europe, Canada and the USA have expressed an ambition to stimulate education of older. In this paper, we analyse if there are effects on annual earnings of formal education for participants aged 42–55 at the time of enrolment in 1994–95. The analysis explores longitudinal population register data stretching from 1982 to 2007. The method used is difference‐in‐differences propensity score matching based on a rich set of covariates, including indicators of health and labor market marginalization. Our findings underline the importance of long follow up periods and imply positive effects for women, especially so for women with children, and no significant average earnings effects for men. These results differ from earlier studies but are stable to several alternative assumptions regarding unobservable characteristics. Data further indicate that the gender gap in our estimates may stem from differences in underlying reasons for enrolment.  相似文献   
20.
A finite number of sellers (n) compete in schedules to supply an elastic demand. The cost of each seller is random, with common and private value components, and the seller receives a private signal about it. A Bayesian supply function equilibrium is characterized: The equilibrium is privately revealing and the incentives to rely on private signals are preserved. Supply functions are steeper with higher correlation among the cost parameters. For high (positive) correlation, supply functions are downward sloping, price is above the Cournot level, and as we approach the common value case, price tends to the collusive level. As correlation becomes maximally negative, we approach the competitive outcome. With positive correlation, private information coupled with strategic behavior induces additional distortionary market power above full information levels. Efficiency can be restored with appropriate subsidy schemes or with a precise enough public signal about the common value component. As the market grows large with the number of sellers, the equilibrium becomes price‐taking, bid shading is on the order of 1/n, and the order of magnitude of welfare losses is 1/n2. The results extend to inelastic demand, demand uncertainty, and demand schedule competition. A range of applications in product and financial markets is presented.  相似文献   
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