155 research outputs found
Quality testing of staple yarn by an instrument with dual sensing and its comparative study with capacitive sensing
An instrument employing both image processing and optical sensing in a single run has been developed to evaluate yarn quality parameters such as irregularity, imperfections and hairiness. Dedicated software, inbuilt within the system, is also developed, which measures the attributes from both the sensors, and a best fit representation is made. The irregularity and imperfections obtained from proposed instrument are compared with those obtained from universally accepted capacitive sensing Uster tester, whereas hairs/meter are compared with Zweigle tester. The cotton, cotton-polyester blended and jute yarns have been tested in all the systems. The repeatability and reliability of results in both image processing and optical sensing are found insignificant in 5% confidence level. It is observed that the yarns with diameter value up to 0.65 mm can be evaluated by optical sensor, but above this threshold, image processing may be done successfully. Uster tester result mostly corroborates with image processing. Optical sensor shows higher values than image processing
A Study on Some Special Forms of Holographic Ricci Dark Energy in Fractal Universe
We have considered the modified and the extended holographic Ricci
dark energy models (MHRDE and EHRDE) in fractal universe. We have assumed a time-like
fractal profile v=t−β, where β=4(1−α). We have reconstructed the Hubble parameter
H, the energy density, the equations of state parameter w, and the deceleration parameter q for both MHRDE and EHRDE
Effect of Site-disorder, Off-stoichiometry and Epitaxial Strain on the Optical Properties of Magnetoelectric Gallium Ferrite
We present a combined experimental-theoretical study demonstrating the role
of site disorder, off-stoichiometry and strain on the optical behavior of
magnetoelectric gallium ferrite. Optical properties such as band-gap,
refractive indices and dielectric constants were experimentally obtained by
performing ellipsometric studies over the energy range 0.8 eV to 4.2 eV on
pulsed laser deposited epitaxial thin films of stoichiometric gallium ferrite
with b-axis orientation and the data was compared with theoretical results.
Calculations on the ground state structure show that the optical activity in
GaFeO3 arises primarily from O2p-Fe3d transitions. Further, inclusion of site
disorder and epitaxial strain in the ground state structure significantly
improves the agreement between the theory and the room temperature experimental
data substantiating the presence of site-disorder in the experimentally derived
strained GaFeO3 films at room temperature. We attribute the modification of the
ground state optical behavior upon inclusion of site disorder to the
corresponding changes in the electronic band structure, especially in Fe3d
states leading to a lowered band-gap of the material.Comment: 18 Pages, 6 figure
HIV Progression Depends on Codon and Amino Acid Usage Profile of Envelope Protein and Associated Host-Genetic Influence
Acquired immune deficiency syndrome (AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV). Two types of HIV have been characterized: HIV-1 and HIV-2. The present study investigated whether evolutionary selection pressure differs between rapid progressor (RP), slow progressor (SP), and long-term non-progressor (LTNP) of HIV-I infected individuals. An unexpected association between the evolutionary rate of substitution in envelope (env) gene and disease progression is observed. Our present study suggests that env genes of LTNP are subject to unusually strong functional constraint with respect to RP. We also observed that the three categories of env genes i.e., RP, SP, and LTNP, had their own characteristic pattern of amino acid usage and SP and LTNP sequences shared similar patterns of amino acid usage different from RP sequences and evolutionary rate significantly influenced the amino acid usage pattern of the three different types of env gene sequences. It was also noted that the evolutionary rate for the glycosylation sites of LTNP and SP sequences were even significantly less than the RP sequences. Comparative analysis on the influence of human host on the three categories of env genes are well correlated with the rates of disease progression suggesting the adaptive strategies of the viruses for successful residence and infection. Host associated selective constraints appeared most relaxed on the RP sequences and strongest in LTNP sequences. The present study clearly portrays how evolutionary selection pressure differs between three categories of env genes i.e., RP, SP, and LTNP. The env genes, coding for the env glycoproteins, experience severe selection constraints from the host due to their constant exposure to the host immune system. In this perspective it might be suggested that env gene evolution occurs mainly by negative selection with the occurrence of mutation that might not reach fixation in the viral population. This work also confers a deeper insight into the crucial effects of host factors that govern the overall progression of HIV infection
Accelerated Aging Experiments for Prognostics of Damage Growth in Composite Materials
Composite structures are gaining importance for use in the aerospace industry. Compared to metallic structures their behavior is less well understood. This lack of understanding may pose constraints on their use. One possible way to deal with some of the risks associated with potential failure is to perform in-situ monitoring to detect precursors of failures. Prognostic algorithms can be used to predict impending failures. They require large amounts of training data to build and tune damage model for making useful predictions. One of the key aspects is to get confirmatory feedback from data as damage progresses. These kinds of data are rarely available from actual systems. The next possible resource to collect such data is an accelerated aging platform. To that end this paper describes a fatigue cycling experiment with the goal to stress carbon-carbon composite coupons with various layups. Piezoelectric disc sensors were used to periodically interrogate the system. Analysis showed distinct differences in the signatures of growing failures between data collected at conditions. Periodic X-radiographs were taken to assess the damage ground truth. Results after signal processing showed clear trends of damage growth that were correlated to damage assessed from the X-ray images
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