Accuracy and precision assesment of stochastic simulation tools for springback variation

The sheet forming industry is plagued by inherent variations in its many input variables, making quality control and improvements a major hurdle. This is particularly poignant for Advanced High Strength Steels (AHSS), which exhibit a large degree of property variability. Current FE-based simulation packages are successful at predicting the manufacturability of a particular sheet metal components, however, due to their numerical deterministic nature are inherently unable to predict the performance of a real-life production process. Though they are now beginning to incorporate the stochastic nature of production in their codes. This work investigates the accuracy and precision of a current stochastic simulation package, AutoForm Sigma v4.1, by developing an experimental data set where all main sources of variation are captured through precise measurements and standard tensile tests. Using a Dual Phase 600Mpa grade steel a series of semi-cylindrical channels are formed at two Blank Holder Pressure levels where the response metric is the variation in springback determined by the flange angle. The process is replicated in AutoForm Sigma and an assessment of accuracy and precision of the predictions are performed. Results indicate a very good correspondence to the experimental trials, with mean springback response predicted to within 1 &deg; of the flange angle and the interquartile spread of results to within 0.22&deg;.<br /

Interference With Privacy - In What Forms Might It Be Actionable in Virginia?

Much has been written about the right of privacy since the 1890 law review article by Samuel Warren and Louis Brandeis which first proposed that such a right be recognized. In the ensuing years the tort of invasion of privacy, which is, in reality, an amalgam of four separate torts, has been widely accepted. In spite of the burgeoning recognition of various rights assembled under the rubric of right to privacy, the Supreme Court of Virginia has never decided whether private citizens are entitled to protection of their personal privacy against invasions by other private citizens. It is the intent of this article to discuss the status of the common law tort of invasion of privacy in Virginia and to consider whether the tort, if it exists in any embryonic stage, would or should be legitimatized. Because of the proliferation of articles and cases discussing various facets of the right of privacy, this article is of limited scope. It makes no attempt to discuss in detail whether particular factual situations should or should not fall within the purview of such a right, to catalogue, review or discuss the right of privacy as developed in other jurisdictions, or to deal with constitutional limitations on governments which grant or ensure a limited right of privacy. Neither does the article discuss the first amendment ramifications necessarily raised by certain branches of the tort of invasion of privacy involving publication of private facts, unauthorized appropriation of one\u27s name or likeness or portrayal of an individual in a false light

Contact pressure prediction in sheet metal forming using finite element analysis

Tool wear has become a significant issue associated with the forming of high strength sheet steels in the automotive industry. In order to combat this problem, recent research has been devoted to utilizing the contact results obtained from current sheet metal forming software predictions, in order to develop/apply tool wear models or tool material selection criteria for use in the stamping plant. This investigation aims to determine whether a specialized sheet metal forming software package can correctly capture the complex contact conditions that occur during a typical sheet metal stamping process. The contact pressure at the die radius was compared to results obtained using a general-purpose finite element software package, for a simple channel-forming process. Although some qualitative similarities between the two predictions were observed, it was found that significant differences in the magnitude and distribution of the contact pressure exists. The reasons for the discrepancies in results are discussed with respect to the simplifications and assumptions adopted in the finite element model definitions, and with regards to other results available in the literature.<br /

Adsorption isotherm determination and heavy metal removal by acid-washed softwood biochar

Heavy metal concentrations above critical range in soils may pose environmental and economic problems by hindering plant growth and limiting land usage. Biochar used as soil amendment is a low-cost, natural remediation technique, which has the capability to immobilize and reduce metals (exchangeable, oxide-bound, and organic matter-bound) bioavailable for plant uptake. Its large surface area provides high capacity for binding metals through sorption reactions. Please click on the file below for full content of the abstract

Effects of temperature in relation to sheet metal stamping

The demand to reduce the use of lubricants and increase tool life in sheet metal stamping has resulted in increased research on the sliding contact between the tool and the sheet materials. Unlubricated sliding wear tests for soft carbon steel sliding on D2 tool steel were performed using a pin-on-disk tribometer. The results revealed that temperature has an influencing role in the wear of tool steel and that material transfer between tool and sheet can be minimized at a certain temperature range in sheet metal stamping

Changing Mindsets: Effectiveness trial

The Changing Mindsets project aimed to improve attainment outcomes at the end of primary school by teaching Year 6 pupils that their brain potential was not a fixed entity but could grow and change through effort exerted. The programme, delivered by Portsmouth University, taught pupils about the malleability of intelligence through workshops. Teachers attended short professional development courses on approaches to developing a ‘growth mindset’ before delivering sessions to pupils weekly, over eight consecutive weeks. Teachers were encouraged to embed aspects of the growth mindset approach throughout their teaching—for example, when giving feedback outside of the sessions. They were also given access to digital classroom resources, such as a video case study of Darwin overcoming adversity in his own life, as a practical example of the importance of having a growth mindset. The project was a randomised controlled trial (RCT) and included 101 schools and 5018 pupils across England, assigned to either intervention or control groups. The trial ran from September 2016 to February 2017. The process evaluation involved interviews with teachers, focus groups with pupils receiving the intervention, lesson observations, and surveys of both treatment schools and control groups throughout the course of the intervention. Key conclusions 1. Pupils in schools that received the intervention did not make any additional progress in literacy nor numeracy—as measured by the national Key Stage 2 tests in reading, grammar, punctuation, and spelling (GPS), and maths—compared to pupils in the control group. This finding has high security. 2. This evaluation also examined four measures of non-cognitive skills: intrinsic value, self-efficacy, test anxiety, and selfregulation. The evaluation did not find evidence of an impact on these measures for pupils in schools that received Changing Mindsets. A positive impact was found for the intrinsic value measure, but the impact was small and was not statistically significant. 3. Among pupils eligible for free school meals (‘FSM pupils’), those in schools that received the intervention did not make any additional progress in literacy nor numeracy—as measured by the national Key Stage 2 tests in reading, GPS, and maths— compared to FSM pupils in schools that did not receive the intervention. 4. One explanation for the absence of a measurable impact on pupil attainment is the widespread use of the growth mindset theory. Most teachers in the comparison schools (that did not receive the intervention) were familiar with this, and over a third reported that they had attended training days based on the growth mindset approach

Transcriptional profiling of Medicago truncatula meristematic root cells

BACKGROUND: The root apical meristem of crop and model legume Medicago truncatula is a significantly different stem cell system to that of the widely studied model plant species Arabidopsis thaliana. In this study we used the Affymetrix Medicago GeneChip® to compare the transcriptomes of meristem and non-meristematic root to identify root meristem specific candidate genes. RESULTS: Using mRNA from root meristem and non-meristem we were able to identify 324 and 363 transcripts differentially expressed from the two regions. With bioinformatics tools developed to functionally annotate the Medicago genome array we could identify significant changes in metabolism, signalling and the differentially expression of 55 transcription factors in meristematic and non-meristematic roots. CONCLUSION: This is the first comprehensive analysis of M. truncatula root meristem cells using this genome array. This data will facilitate the mapping of regulatory and metabolic networks involved in the open root meristem of M. truncatula and provides candidates for functional analysis.This research is supported by a grant from the Australian Research Council Centre of Excellence Program (CE0348212). PH was supported by an Australian Postgraduate Award. We thank Lily Shen from the ANU Electron Microscopy Unit for assistance with microscopy

Evaluating the potential of biochar for reducing bioavailable heavy metal fractions in polluted soil

Previous studies have proposed biochar as a natural adsorbent material with potential to be used in the remediation of polluted soils. Its application for adsorption of pollutants may reduce the bioavailability of harmful compounds in the soil media by limiting its chemical distribution and reducing the risk of uptake by organisms. Therefore, biochar has been suggested for the attenuation of heavy metals (HMs) in soil, minimizing the possibility of accumulation through the trophic chain (Figure ). Please click on the file below for full content of the abstract

Transcriptional profiling of Medicago truncatula meristematic root cells

<p>Abstract</p> <p>Background</p> <p>The root apical meristem of crop and model legume <it>Medicago truncatula </it>is a significantly different stem cell system to that of the widely studied model plant species <it>Arabidopsis thaliana</it>. In this study we used the Affymetrix <it>Medicago </it>GeneChip^®to compare the transcriptomes of meristem and non-meristematic root to identify root meristem specific candidate genes.</p> <p>Results</p> <p>Using mRNA from root meristem and non-meristem we were able to identify 324 and 363 transcripts differentially expressed from the two regions. With bioinformatics tools developed to functionally annotate the <it>Medicago </it>genome array we could identify significant changes in metabolism, signalling and the differentially expression of 55 transcription factors in meristematic and non-meristematic roots.</p> <p>Conclusion</p> <p>This is the first comprehensive analysis of <it>M. truncatula </it>root meristem cells using this genome array. This data will facilitate the mapping of regulatory and metabolic networks involved in the open root meristem of <it>M. truncatula </it>and provides candidates for functional analysis.</p