Grit

Many of our most important goals require months or even years of effort to achieve, and some never get achieved at all. As social psychologists have lately emphasized, success in pursuing such goals requires the capacity for perseverance, or "grit." Philosophers have had little to say about grit, however, insofar as it differs from more familiar notions of willpower or continence. This leaves us ill-equipped to assess the social and moral implications of promoting grit. We propose that grit has an important epistemic component, in that failures of perseverance are often caused by a significant loss of confidence that one will succeed if one continues to try. Correspondingly, successful exercises of grit often involve a kind of epistemic resilience in the face of failure, injury, rejection, and other setbacks that constitute genuine evidence that success is not forthcoming. Given this, we discuss whether and to what extent displays of grit can be epistemically as well as practically rational. We conclude that they can be (although many are not), and that the rationality of grit will depend partly on features of the context the agent normally finds herself in. In particular, grit-friendly norms of deliberation might be irrational to use in contexts of severe material scarcity or oppression

Impact of surface-polish on the angular and wavelength dependence of fiber focal ratio degradation

We present measurements of how multimode fiber focal-ratio degradation (FRD) and throughput vary with levels of fiber surface polish from 60 to 0.5 micron grit. Measurements used full-beam and laser injection methods at wavelengths between 0.4 and 0.8 microns on 17 meter lengths of Polymicro FBP 300 and 400 micron core fiber. Full-beam injection probed input focal-ratios between f/3 and f/13.5, while laser injection allowed us to isolate FRD at discrete injection angles up to 17 degrees (f/1.6 marginal ray). We find (1) FRD effects decrease as grit size decreases, with the largest gains in beam quality occurring at grit sizes above 5 microns; (2) total throughput increases as grit size decreases, reaching 90% at 790 nm with the finest polishing levels; (3) total throughput is higher at redder wavelengths for coarser polishing grit, indicating surface-scattering as the primary source of loss. We also quantify the angular dependence of FRD as a function of polishing level. Our results indicate that a commonly adopted micro-bending model for FRD is a poor descriptor of the observed phenomenon.Comment: 10 pages, 7 figures, presented at SPIE Astronomical Telescopes and Instrumentation, July 201

Single Grit Grinding Simulation by Using Finite Element Analysis

In this research, basic material removal characteristics in a single grit grinding have been investigated by using Finite Element Analysis (FEA). ABAQUS/Standard is used as a computational environment. The influences of both friction and undeformed chip thickness are considered in the analyses of the grit ploughing, stress distribution and total force variation. Remeshing strategy is performed in the simulation to produce very fine meshes in the contact area to mitigate the material distortion due to large plastic deformation. The results show that the increase of undeformed chip thickness and frictional coefficient would increase ploughing action and grinding stress magnitude. Moreover, friction would cause the stress distribution circle on grit inclined backwards. Finally, FEM analysis can be considered as a strong tool for the single grit simulation of grinding process. ©2010 American Institute of Physic

A clash of constructs? : re-examining grit in light of academic buoyancy and future time perspective

Grit, defined as perseverance and passion for long-term goals, has been found to be a powerful predictor of student success and persistence. Yet, it has been recently scrutinized construct due to weaknesses in discriminant and predictive validity of its measure. To investigate these issues further, I examined grit, its dimensions (perseverance of effort and consistency of interest), and other motivational factors--academic buoyancy and future time perspective--to test whether they were distinct constructs, and whether they were predictors of academic achievement, incorporating individual differences in gender, ethnicity, and major. The current study revealed that grit positively predicted undergraduates’ GPA (N = 328) over and beyond demographic and other motivational variables. Regarding individual differences, men and women differed on subscales of future time perspective, and Asian Americans reported lower grit compared to White and Hispanic students, despite higher GPA compared to Hispanics. The relevance of the findings is discussed along with implications for research and practice.Educational Psycholog

Experimental and numerical study on scratching test

This paper presents recent investigation of the material removal mechanism in single grit grinding test. Single grit scratches were generated experimentally by using CBN grit on En24T steel and compared with numerical simulation by using finite element modelling (FEM). The material removal mechanism was observed along the scratch length to understand the effectiveness of ploughing and cutting mechanism throughout the scratch. Experiments showed that cutting is efficient at first half of the scratch while ploughing is significantly higher at the second half of the scratch. At the exit side of the scratch almost no material removal takes place. It has demonstrated that FEM simulations match well with experimental results

Institutional Childcare: An Overview on the German Market

Institutional early childhood education and care can be funded and delivered in various ways relying on both the public and the private sector. The provision of childcare ranges from public operation to mixed markets with public and private providers to considerably marketised systems with predominantly private providers. One of the countries with a mixed childcare system is Germany where most of the childcare centres are operated by local authorities and non-profit organisations. Using newly available statistical data this paper provides a descriptive overview on the market for childcare in Germany from a providers' perspective. It answers the question if providers differ systematically with regard to centre characteristics, staff employed or the children taken care of. As the results show, the differences in operation affect many dimensions, nevertheless non-religious and for-profit centres on the one hand as well as public and religious centres on the other hand tend show similar characteristics. --institutional childcare,provision,public and private sector

Final report of grit blasting and metal spraying trials carried out at H. M. Dockyard, Devonport

Mild steel surfaces that are to be protected by aluminium or zinc spray coatings are generally prepared by blasting with chilled iron angular grit. Previous work1had shown that a relationship exists between the grit blasting conditions (at least in terms of blasting angle and grit condition), the reflectivity of the blasted surface and the bond strength of a spray coating of aluminium on the blasted surface. An instrument has been developed that assesses the suitability of a blasted surface for subsequent spraying by measuring the reflectivity and has proved reasonably successful under laboratory conditions. The present need is to ascertain the performance of this reflectivity meter under shop and site conditions. The opportunity to carry out such tests at H.M. Dockyard, Devonport, was offered by the Ministry of Defence and a series of tests was made on 16th June, 1965

Method and apparatus for gripping uniaxial fibrous composite materials

A strip specimen is cut from a unidirectional strong, brittle fiber composite material, and the surfaces of both ends of the specimen are grit blasted. The specimen is then placed between metal load transfer members having grit blasted surfaces. Sufficient compressive stress is applied to the load transfer members to prevent slippage during testing at both elevated temperatures and room temperatures. The need for adhesives, load pads, and other secondary composite processing is eliminated. This gripping system was successful in tensile testing, creep rupture testing, and fatigue testing uniaxial composite materials at 316 C

Do NEETs Need Grit?

This paper investigates the relationship between personality traits in adolescence and education and labour market choices. In particular, we investigate the impact of grit (a tendency and ability to sustain interest in long term goals - perseverance) on the risk of youths being NEET – "Not in Education, Employment or Training". Thus, our focus is on early drop-out from the labour market and education at age 18-20. Individuals with high levels of grit are less likely to be out of education or employment, while low self-esteem and external locus of control increase the chances of experiencing these conditions.We use propensity score matching to control for a rich set of adolescent and family characteristics and our results show that personality traits do affect education and employment choices. We test the robustness of our results using the methodology proposed by Altonji et al. (2005) that consists of making hypotheses about the correlation between the unobservables and observables that determine the outcomes and the unobservables that influence personality