30 resultados para Stability and Robustness

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A series of three experiments were conducted with second cross ([Merino×Border Leicester]×Poll Dorset) wether lambs to evaluate the effects of dietary treatments on manipulation of muscle long-chain (LC) omega-3 fatty acids (FA) on the color stability and oxidative stability of fresh and vacuum packaged lamb. At the end of 7-, 6- and 6-week experimental periods for experiments (Exp.) 1–3 respectively, lambs were slaughtered at a commercial abattoir. At 24 h post-mortem, muscle longissimus lumborum (LL) and longissimus thoracis (LT) were removed and evaluated for color and lipid oxidative stability under specified commercial storage and display condition. Of the dietary supplements used, fish meal and fish oil moderately (P<0.01) and markedly (P<0.001) increased muscle omega-3 FA content, while both protected canola seed (P<0.001) and protected sunflower meal protein significantly (P<0.02) increased muscle omega-6 FA content or ratio of omega-6/omega-3 of the longissimus muscle. In all experiments, the substantial increase (P<0.001) in muscle LC omega-3 and omega-6 FA had no consistent significant effect on color values (redness (a*), yellowness (b*) and lightness (L*)) for fresh and vacuum packaged lamb over a 6-day display period. Lipid oxidation, determined by the levels of thiobarbituric acid reactive substances (TBARS) indicated the enrichment of muscle polyunsaturated fatty acid (PUFA) levels in lambs did not produce significant differences resulting either from main treatment effects or for treatment×day×type interactions (where type was fresh and vacuum packaged). Present results demonstrated the color and lipid oxidative stability of lamb longissimus muscle during refrigerated display was not affected by enhanced levels of omega-3 and omega-6 FA due to dietary treatments.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A series of three experiments were conducted with second cross ([Merino×Border Leicester]×Poll Dorset) wether lambs to evaluate the effects of dietary treatments on manipulation of muscle long-chain (LC) omega-3 fatty acids (FA) on the color stability and oxidative stability of fresh and vacuum packaged lamb. At the end of 7-, 6- and 6-week experimental periods for experiments (Exp.) 1–3 respectively, lambs were slaughtered at a commercial abattoir. At 24 h post-mortem, muscle longissimus lumborum (LL) and longissimus thoracis (LT) were removed and evaluated for color and lipid oxidative stability under specified commercial storage and display condition. Of the dietary supplements used, fish meal and fish oil moderately (P<0.01) and markedly (P<0.001) increased muscle omega-3 FA content, while both protected canola seed (P<0.001) and protected sunflower meal protein significantly (P<0.02) increased muscle omega-6 FA content or ratio of omega-6/omega-3 of the longissimus muscle. In all experiments, the substantial increase (P<0.001) in muscle LC omega-3 and omega-6 FA had no consistent significant effect on color values (redness (a*), yellowness (b*) and lightness (L*)) for fresh and vacuum packaged lamb over a 6-day display period. Lipid oxidation, determined by the levels of thiobarbituric acid reactive substances (TBARS) indicated the enrichment of muscle polyunsaturated fatty acid (PUFA) levels in lambs did not produce significant differences resulting either from main treatment effects or for treatment×day×type interactions (where type was fresh and vacuum packaged). Present results demonstrated the color and lipid oxidative stability of lamb longissimus muscle during refrigerated display was not affected by enhanced levels of omega-3 and omega-6 FA due to dietary treatments.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A series of three experiments were conducted with second cross ([Merino×Border Leicester]×Poll Dorset) wether lambs to evaluate the effects of dietary treatments on manipulation of muscle long-chain (LC) omega-3 fatty acids (FA) on the color stability and oxidative stability of fresh and vacuum packaged lamb. At the end of 7-, 6- and 6-week experimental periods for experiments (Exp.) 1–3 respectively, lambs were slaughtered at a commercial abattoir. At 24 h post-mortem, muscle longissimus lumborum (LL) and longissimus thoracis (LT) were removed and evaluated for color and lipid oxidative stability under specified commercial storage and display condition. Of the dietary supplements used, fish meal and fish oil moderately (P<0.01) and markedly (P<0.001) increased muscle omega-3 FA content, while both protected canola seed (P<0.001) and protected sunflower meal protein significantly (P<0.02) increased muscle omega-6 FA content or ratio of omega-6/omega-3 of the longissimus muscle. In all experiments, the substantial increase (P<0.001) in muscle LC omega-3 and omega-6 FA had no consistent significant effect on color values (redness (a*), yellowness (b*) and lightness (L*)) for fresh and vacuum packaged lamb over a 6-day display period. Lipid oxidation, determined by the levels of thiobarbituric acid reactive substances (TBARS) indicated the enrichment of muscle polyunsaturated fatty acid (PUFA) levels in lambs did not produce significant differences resulting either from main treatment effects or for treatment×day×type interactions (where type was fresh and vacuum packaged). Present results demonstrated the color and lipid oxidative stability of lamb longissimus muscle during refrigerated display was not affected by enhanced levels of omega-3 and omega-6 FA due to dietary treatments.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this paper, the stability and convergence properties of the class of transform-domain least mean square (LMS) adaptive filters with second-order autoregressive (AR) process are investigated. It is well known that this class of adaptive filters improve convergence property of the standard LMS adaptive filters by applying the fixed data-independent orthogonal transforms and power normalization. However, the convergence performance of this class of adaptive filters can be quite different for various input processes, and it has not been fully explored. In this paper, we first discuss the mean-square stability and steady-state performance of this class of adaptive filters. We then analyze the effects of the transforms and power normalization performed in the various adaptive filters for both first-order and second-order AR processes. We derive the input asymptotic eigenvalue distributions and make comparisons on their convergence performance. Finally, computer simulations on AR process as well as moving-average (MA) process and autoregressive-moving-average (ARMA) process are demonstrated for the support of the analytical results.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The tryout process at an automotive sheet metal production plant is outlined and analysed with the aim of augmenting the process to improve robustness through an understanding of variation using Finite Element (FE) analysis and other tools. The result is tryout can produce a more robust stamping process.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Purpose. Three studies examined the degree to which investigative interviewers’ adherence to best-practice guidelines is consistent across similar mock interviews.
Method. In each study, two interviews were administered within a period of several hours. Further, group and individual stability of interviewer performance was analysed, and performance was measured by calculating the proportion of open-ended and leading questions as well as the presence of predetermined problem behaviours. The studies varied depending on the type of interview paradigm employed. Interviewer performance in Study 1was measured in a group context where participants rotated between the role of interviewer, child respondent, and observer. In Study 2, an adult played the role of a child recalling abuse but this occurred in isolation (participants did not observe others or play the child). Study 3 was similar to Study 2 except that in each interview an unfamiliar child aged 5–7 years recalled an innocuous event.
Results. Interviewer performance was relatively stable across tasks, although the strength of the relationship between measures varied across analyses. Improvement in open-ended question usage occurred in Study 1 but not Studies 2 and 3. Irrespective of the assessment context, the dichotomous rating scale yielded greater consistency than when questions were tallied. Further, group stability overestimated individual stability. The practical implications of these findings for trainers and researchers are discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper proposes an effective pseudonoise (PN) sequence and the corresponding decoding function for time-spread echo-based audio watermarking. Different from the traditional PN sequence used in time-spread echo hiding, the proposed PN sequence has two features. Firstly, the echo kernel resulting from the new PN sequence has frequency characteristics with smaller magnitudes in perceptually significant region. This leads to higher perceptual quality. Secondly, the correlation function of the new PN sequence has three times more large peaks than that of the existing PN sequence. Based on this feature, we propose a new decoding function to improve the robustness of time-spread echo-based audio watermarking. The effectiveness of the proposed PN sequence and decoding function is illustrated by theoretical analysis, simulation examples, and listening test.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Colistin is an amphiphilic antibiotic that has re-emerged into clinical use due to the increasing prevalence of difficult-to-treat Gram-negative infections. The existence of self-assembling colloids in solutions of colistin and its derivative prodrug, colistin methanesulfonate (CMS), was investigated. Colistin and CMS reduced the air−water interfacial tension, and dynamic light scattering (DLS) studies showed the existence of 2.07 ± 0.3 nm aggregates above 1.5 mM for colistin and of 1.98 ± 0.36 nm aggregates for CMS above 3.5 mM (mean ± SD). Above the respective critical micelle concentrations (CMC) the solubility of azithromycin, a hydrophobic antibiotic, increased approximately linearly with increasing surfactant concentration (5:1 mol ratio colistin:azithromycin), suggestive of hydrophobic domains within the micellar cores. Rapid conversion of CMS to colistin occurred below the CMC (60% over 48 h), while conversion above the CMC was less than 1%. The formation of colistin and CMS micelles demonstrated in this study is the proposed mechanism for solubilization of azithromycin and the concentration-dependent stability of CMS.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The red-emitting phosphors Ca9Eu2W4O24 and Sr9Eu2W4O24 were synthesized by the solid-state reaction method. The crystal phases were characterized by X-ray powder diffraction. The photoluminescence excitation and emission spectra were investigated. The luminescence excitation and emission spectra confirm that the phosphors are efficiently excited by near UV light. The dependence of luminescence intensities on the heating temperatures was investigated. The Ca9Eu2W4O24 phosphor exhibits higher thermal stability than that of Sr9Eu2W4O24. The crystallographic sites for Eu3+ ions in Ca9Eu2W4O24 and Sr9Eu2W4O24 are investigated by the site-selective excitation spectra in the 5D07F0 wavelength region. It is identified that the Eu3+ ions occupy only M sites (statistically occupied by 0.5Eu and 0.5Ca) in Ca9Eu2W4O24 and, however, the Eu3+ ions can substitute both M sites (Eu3+ + Sr2+) and Sr2+ sites in Sr9Eu2W4O24. The luminescence spectra and the thermal stability are discussed on the basis of the crystal structure, Eu3+ site-distributions and the energy transfer.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Resistance to treatment is common among anorexic clients. Three studies indicated that although readiness to change and self-efficacy are applicable to this population, there is a large degree of variability and stability between symptoms. Multi-dimensional, continuous measures of readiness to change and self-efficacy may provide a more accurate, informative assessment.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Total immunoglobulin A in saliva (s-IgA) is normally assayed using an enzyme-linked immunosorbent assay. We have investigated methodological issues relating to the use of particle-enhanced nephelometric immunoassay (PENIA)
to measure s-IgA in whole unstimulated saliva and determine its reference range.

Methods: Whole unstimulated resting saliva was collected to determine sample stability (temperature, time, effect of a protease inhibitor), limit of quantitation (LOQ), assay precision and analytical variation. The reference range for 134 healthy adults was determined.

Results: Linearity was excellent (4–10.3 mg L21, P, 0.001; R2 ¼ 0.997) and without significant bias (mean of 20.7%). The lowest intra- and inter-analytical coefficients of variation were 1.8% and 7.5% and LOQ was 1.4 mg L21. The concentration of s-IgA is stable at room temperature for up to 6 h, at 48C for 48 h, at 248C for two weeks and at 2808C for up to 1.3 yr. There is no evidence that a protease inhibitor increases the stability or that repeated freeze–thawing cycles degrade sample quality. The reference ranges for s-IgA concentration, s-IgA secretion, s-IgA:albumin and s-IgA:osmolality were 15.9–414.5 mg L21, 7.2–234.9 mg min21, 0.4–19 and 0.6–8.9, respectively.

Conclusion:
Automated PENIA assay of s-IgA is precise and accurate. High stability of collected saliva samples and the ease and speed of the assay make this an ideal method for use in athletic and military training situations. The convenience of measuring albumin and IgA on the same analytical platform adds to the practicability of the test.