275 research outputs found
The Reed-Stanton press rig for the generation of reproducible fingermarks : towards a standardised methodology for fingermark research
In the search for better or new methods/techniques to visualise fingermarks or to analyse them exploiting their chemical content, fingermarks inter-variability may hinder the assessment of the method effectiveness. Variability is due to changes in the chemical composition of the fingermarks between different donors and within the same donor, as well as to differential contact time, pressure and angle. When validating a method or comparing it with existing ones, it is not always possible to account for this type of variability. One way to compensate for these issues is to employ, in the early stages of the method development, a device generating reproducible fingermarks. Here the authors present their take on such device, as well as quantitatively describing its performance and benefits against the manual production of marks. Finally a short application is illustrated for the use of this device, at the method developmental stages, in an emerging area of fingerprinting research concerning the retrieval of chemical intelligence from fingermarks
Noise reduction of automobile cooling fan based on bio-inspired design
This study aims to minimize the noise generated by automobile cooling fans. Fan blade structures with ridged surfaces based on bio-inspired principles are 3D printed and used to replace the conventional fan blades. The effect of the bio-inspired ridge structures on the noise reduction of the cooling fan is demonstrated by orthogonal experiments in a semi-anechoic chamber. Experimental results show that with an increase in the rotational speed, the effect of the surface textures on the acoustic performance of the cooling fan becomes more significant. For example, at a fan speed of 1750âr/min, all the bio-inspired blade designs reduce noise compared with the original fan and, in particular, the sound pressure level is reduced by 3.83âdB(A) for the design with a ridge width of 4âmm and a ridge pitch of 15âmm. Through variance analysis of the measured noise, the ridge pitch distance has the most significant impact on noise reduction under low speed conditions whilst, under high speed conditions, the ridge width has the most significant influence. In addition to the experimental studies, computational fluid dynamics (CFD) simulations of the cooling fan are carried out to explain the mechanism of noise reduction for the ridged fan blades. When the fan runs, the horseshoe vortexes generated by the ridge structures disturb the flow of the boundary layer, reduce the influence of the fluid flow on the boundary layer, and delay the transition of the fan blade laminar flow to turbulence. It is also seen that there is a reduction of the intensity of the fan blade trailing edge vortices and the scale of the secondary vortices, thereby achieving the overall aim of noise reduction. This research has significance in the noise reduction design of automobile cooling fans
Defining a self-evaluation digital literacy framework for secondary educators: the DigiLit Leicester project
Despite the growing interest in digital literacy within educational policy, guidance for secondary educators in terms of how digital literacy translates into the classroom is lacking. As a result, many teachers feel ill-prepared to support their learners in using technology effectively. The DigiLit Leicester project created an infrastructure for holistic, integrated change, by supporting staff development in the area of digital literacy for secondary school teachers and teaching support staff. The purpose of this article is to demonstrate how the critique of existing digital literacy frameworks enabled a self-evaluation framework for practitioners to be developed. Crucially, this framework enables a co-operative, partnership approach to be taken to pedagogic innovation. Moreover, it enables social and ethical issues to underpin a focus on teacher-agency and radical collegiality inside the domain of digital literacy. Thus, the authors argue that the shared development framework constitutes a new model for implementing digital literacy aimed at transforming the provision of secondary education across a city
The impact of the Great Exhibition of 1851 on the development of technical education during the second half of the nineteenth century
This paper examines the contribution made by the mechanicsâ institute movement in Britain just prior to, and following, the opening of the Great Exhibition of 1851 in London. It argues that far from making little contribution to education, as often portrayed by historians, the movement was ideally positioned to respond to the findings of the Exhibition, which were that foreign goods on display were often more advanced than those produced in Britain. The paper highlights, through a regional study, how well suited mechanicsâ institutes were in organising their own exhibitions, providing the idea of this first international exhibition. Subsequently, many offered nationally recognised technical subject examinations through relevant education as well as informing government commissions, prior to the passing of the Technical Instruction Acts in 1889 and the Local Taxation Act of 1890. These acts effectively put mechanicsâ institutes into state ownership as the first step in developing further education for all in Britai
Associations Between Nutrient Intake and Corresponding Nutritional Biomarker Levels in Blood in a Memory Clinic Cohort:The NUDAD Project
Diet is a promising intervention target to prevent or slow Alzheimer's disease (AD). Early (predementia) stages of AD offer a unique opportunity for dietary interventions. Nutritional assessment methods to estimate nutrient intake have, however, not been validated in clinical populations. Hence, we assessed the association between nutrient intake assessed by food frequency questionnaire (FFQ) and nutrient status measured by nutritional biomarkers in blood in a clinical sample of controls, mild cognitive impairment (MCI), and patients with AD
Locating mathematics within post-16 vocational education in England
The political importance of mathematics in post-16 education is clear. Far less clear is how mathematics does and should relate to vocational education. Successive mathematics curricula (e.g. core skills, key skills) have been developed in England with vocational learners in mind. Meanwhile, general mathematics qualifications remain largely disconnected from vocational learning. Following a brief historical survey of mathematics within vocational education, the paper presents findings from a nested case study of student groups in three large Further Education colleges in England. The primary unit of analysis herein is student groups learning Functional Mathematics in two vocational areas: construction and hairdressing. We show how approaches to organising teaching, developing connected curricula and classroom pedagogy tend to isolate or integrate mathematics from/with the vocational experience. Integrated approaches are shown to impact positively on student engagement and attitudes to learning mathematics. The paper concludes by discussing the potential impact of academic qualifications displacing vocationally relevant mathematics
Beyond change scores: Employing an improved statistical approach to analyze the impact of entry fitness on physical performance during British Army basic training in men and women
AbstractThe aim was to use a robust statistical approach to examine whether physical fitness at entry influences performance changes between men and women undertaking British Army basic training (BT). Performance of 2 km run, seated medicine ball throw (MBT) and isometric midâthigh pull (MTP) were assessed at entry and completion of Standard Entry (SE), Junior EntryâShort (JEâShort), and Junior EntryâLong (JEâLong) training for 2350 (272 women) recruits. Performance change was analyzed with entry performance as a covariate (ANCOVA), with an additional interaction term allowing different slopes for courses and genders (p < 0.05). Overall, BT courses saw average improvements in 2 km run performance (SE: â6.8% [â0.62 min], JEâShort: â4.6% [â0.43 min], JEâLong: â7.7% [â0.70 min]; all p < 0.001) and MBT (1.0â8.8% [0.04â0.34 m]; all p < 0.05) and MTP (4.5â26.9% [6.5â28.8 kg]; all p < 0.001). Regression models indicate an expected form of âregression to the meanâ whereby test performance change was negatively associated with entry fitness in each course (those with low baseline fitness exhibit larger training improvements; all interaction effects: p < 0.001, > 0.006), particularly for women. However, when matched for entry fitness, men displayed considerable improvements in all tests, relative to women. Training courses were effective in developing recruit physical fitness, whereby the level of improvement is, in large part, dependent on entry fitness. Factors including age, physical maturity, course length, and physical training, could also contribute to the variability in training response between genders and should be considered when analyzing and/or developing physical fitness in these cohorts for future success of military jobâtask performance
COVIDâ19, nationalism, and the politics of crisis: A scholarly exchange
In this article, several scholars of nationalism discuss the potential for the COVIDâ19 pandemic to impact the development of nationalism and world politics. To structure the discussion, the contributors respond to three questions: (1) how should we understand the relationship between nationalism and COVIDâ19; (2) will COVIDâ19 fuel ethnic and nationalist conflict; and (3) will COVIDâ19 reinforce or erode the nationâstate in the long run? The contributors formulated their responses to these questions near to the outset of the pandemic, amid intense uncertainty. This made it acutely difficult, if not impossible, to make predictions. Nevertheless, it was felt that a historically and theoretically informed discussion would shed light on the types of political processes that could be triggered by the COVIDâ19 pandemic. In doing so, the aim is to help orient researchers and policyâmakers as they grapple with what has rapidly become the most urgent issue of our times
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