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Acoustic emission and vibration for tool wear monitoring in single-point
This paper proposes an implementation of calibrated acoustic emission (AE) and vibration techniques to monitor progressive stages of flank wear on carbide tool tips. Three cutting conditions were used on workpiece material, type EN24T, in turning operation. The root-mean-square value of AE (AErms) and the coherence function between the acceleration signals at the tool tip in the tangential and feed directions was studied. Three features were identified to be sensitive to tool wear: AErms, coherence function in the frequency ranges 2.5-5.5 kHz and 18-25 kHz. Belief network based on Bayesâ rule was used to integrate information in order to recognise the occurrence of worn tool. The three features obtained from the three cutting conditions and machine time were used to train the network. The set of feature vectors for worn tools was divided into two equal sub-sets: one to train the network and the other to test it. The AErms in term of AE pressure equivalent was used to train and test the net work to validate the calibrated acoustic. The overall success rate of the network in detecting a worn tool was high with low error rate
Renormalization Constants of Quark Operators for the Non-Perturbatively Improved Wilson Action
We present the results of an extensive lattice calculation of the
renormalization constants of bilinear and four-quark operators for the
non-perturbatively O(a)-improved Wilson action. The results are obtained in the
quenched approximation at four values of the lattice coupling by using the
non-perturbative RI/MOM renormalization method. Several sources of systematic
uncertainties, including discretization errors and final volume effects, are
examined. The contribution of the Goldstone pole, which in some cases may
affect the extrapolation of the renormalization constants to the chiral limit,
is non-perturbatively subtracted. The scale independent renormalization
constants of bilinear quark operators have been also computed by using the
lattice chiral Ward identities approach and compared with those obtained with
the RI-MOM method. For those renormalization constants the non-perturbative
estimates of which have been already presented in the literature we find an
agreement which is typically at the level of 1%.Comment: 36 pages, 13 figures. Minor changes in the text and in one figure.
Accepted for publication on JHE
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'We're not like that': Crusader and Maverick Occupational Identity Resistance
This article explores the occupational identities of hairdressers and vehicle mechanics working in small and micro-firms. Using qualitative interview data from two UK cities, it examines the ways that workers expounded, reflected on and discursively reframed public perceptions of their occupation. A novel distinction between two types of identity reframing is proposed. âCrusadersâ are workers who reject characterisations as inappropriate for the occupation at large, whereas âmavericksâ accept that popular characterisations apply to other workers but differentiate themselves. The analysis identifies differences in occupational identity resistance strategies (crusader or maverick) when workers interact with two different publics: customers and trainees
Conditions on Iterative Rounding Harmony in Oroqen
In this paper, we re-examine the claim that Baiyinna Oroqen, a language of the Tungusic family with a largely predictable distribution of non-high round vowels, requires a non-iterative type of rounding harmony, by demonstrating instead the need for a clear distinction between stem-internal morpheme structure constraints and suffixal vowel harmony. We also propose to revise what was thought to be a requirement that harmony donors must be anchored in two successive syllables; it is instead a restriction that copying of the harmonic feature must be from the closest non-initial vowel
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Predominance of weakly cytotoxic, T-betLowEomesNeg CD8+ T-cells in human gastrointestinal mucosa: implications for HIV infection.
The gastrointestinal mucosa is an important site of HIV acquisition, viral replication, and pathogenesis. Immune cells in mucosal tissues frequently differ in phenotype and function from their non-mucosal counterparts. Although perforin-mediated cytotoxicity as measured in blood is a recognized correlate of HIV immune control, its role in gastrointestinal tissues is unknown. We sought to elucidate the cytotoxic features of rectal mucosal CD8+ T-cells in HIV infected and uninfected subjects. Perforin expression and lytic capacity were significantly reduced in rectal CD8+ T-cells compared with their blood counterparts, regardless of HIV clinical status; granzyme B (GrzB) was reduced to a lesser extent. Mucosal perforin and GrzB expression were higher in participants not on antiretroviral therapy compared with those on therapy and controls. Reduction in perforin and GrzB was not explained by differences in memory/effector subsets. Expression of T-bet and Eomesodermin was significantly lower in gut CD8+ T-cells compared with blood, and in vitro neutralization of TGF-ÎČ partially restored perforin expression in gut CD8+ T-cells. These findings suggest that rectal CD8+ T-cells are primarily non-cytotoxic, and phenotypically shaped by the tissue microenvironment. Further elucidation of rectal immune responses to HIV will inform the development of vaccines and immunotherapies targeted to mucosal tissues
Poor Outcome in a Mitochondrial Neurogastrointestinal Encephalomyopathy Patient with a Novel TYMP Mutation: The Need for Early Diagnosis.
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a devastating autosomal recessive disorder due to mutations in TYMP, which cause loss of function of thymidine phosphorylase (TP), nucleoside accumulation in plasma and tissues and mitochondrial dysfunction. The clinical picture includes progressive gastrointestinal dysmotility, cachexia, ptosis and ophthalmoparesis, peripheral neuropathy and diffuse leukoencephalopathy, which usually lead to death in early adulthood. Therapeutic options are currently available in clinical practice (allogeneic hematopoietic stem cell transplantation and carrier erythrocyte entrapped TP therapy) and newer, promising therapies are expected in the near future. However, successful treatment is strictly related to early diagnosis. We report on an incomplete MNGIE phenotype in a young man harboring the novel heterozygote c.199 C>T (Q67X) mutation in exon 2, and the previously reported c.866 A>C (E289A) mutation in exon 7 in TYMP. The correct diagnosis was achieved many years after the onset of symptoms and unfortunately, the patient died soon after diagnosis because of multiorgan failure due to severe malnutrition and cachexia before any therapeutic option could be tried. To date, early diagnosis is essential to ensure that patients have the opportunity to be treated. MNGIE should be suspected in all patients who present with both gastrointestinal and nervous system involvement, even if the classical complete phenotype is lacking
Conceptual Design of Fuel Dumping System in Aircraft
Airlines release the unburned jet fuel into the atmosphere to reduce the weight of aircraft before landing. Sometimes, aircraft reach a weight more than takeoff weight while departing from the airport. Therefore, the pilot follows the ATC comment to dump fuel into the atmosphere to reduce the aircraft\u27s weight to avoid accidents. Due to fuel dumping, an airline faces fuel consumption, loss, and several diseases affect environmental pollutants, and living things. The total fuel consumption of commercial airlines worldwide in 2021 is 57 billion gallons. If jet fuel routinely hit the ground, it would pollute water and land and damage crops and biodiversity. With this, we have worked on the project to rescue fuel dumping into the atmosphere and save living things from various diseases
Pinwheel patterns and powder diffraction
Pinwheel patterns and their higher dimensional generalisations display
continuous circular or spherical symmetries in spite of being perfectly
ordered. The same symmetries show up in the corresponding diffraction images.
Interestingly, they also arise from amorphous systems, and also from regular
crystals when investigated by powder diffraction. We present first steps and
results towards a general frame to investigate such systems, with emphasis on
statistical properties that are helpful to understand and compare the
diffraction images. We concentrate on properties that are accessible via an
alternative substitution rule for the pinwheel tiling, based on two different
prototiles. Due to striking similarities, we compare our results with the toy
model for the powder diffraction of the square lattice.Comment: 7 pages, 4 figure
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