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871.
Implementation of process analytical technology (PAT) tools in the manufacturing process of liquid detergent compositions should allow fast and non-destructive evaluation of the product quality. The aim of this study was to develop and validate a rapid method for quantifying the chemical compounds of five washing liquid precursors. Raman spectroscopy was applied in combination with a two-step multivariate modeling procedure. In first instance, a SIMCA (Soft Independent Modeling of Class Analogy) model was developed and validated, allowing the distinction between the different laundry detergents. Once the product was correctly identified, it was aimed at predicting the concentration of its individual components using partial least squares (PLS) models. Raman spectra were collected at-line with a total acquisition time of 20 s, using a non-contact fiber-optic probe. 相似文献
872.
This paper presents a quantitative risk assessment for design and development of a renewable energy system to support decision‐making among design alternatives. Throughout the decision‐making phases, resources are allocated among exploration and exploitation tasks to manage the uncertainties in design parameters and to adapt designs to new information for enhanced performance. The resource allocation problem is formulated as a sequential decision feedback loop for a quantitative analysis of exploration and exploitation trade‐offs. We support decision‐making by tracking the evolution of uncertainties, the sensitivity of design alternatives to the uncertainties, and the performance, reliability, and robustness of each design. This is achieved by analyzing the uncertainties in the wind resource, the turbine performance and operation, and the models that define the power curve and wake deficiency. Comparison of the performance, reliability, and robustness of aligned and staggered turbine layouts before and after wind assessment experiments aids in improving micro‐siting decisions. The results demonstrate that design decisions can be supported by efficiently allocating resources towards improved estimates of achievable design objectives and by quantitatively assessing the risk in meeting those objectives. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
873.
Uncertainty calculations in the certification of reference materials. 2. Homogeneity study 总被引:4,自引:0,他引:4
Many reference materials undergo a batch certification, which implies that a small number of samples is taken from a batch,
characterised, and these results are then assumed to be representative of all remaining samples. An important aspect in this
design is the translation of the characterisation data to a single sample, as usually the laboratory will be using only one
sample of the batch. This form of homogeneity is very important and can be influenced to a certain extent by well-designed
sample preparation procedures. Another subsampling problem associated with many reference materials is that only a small test
portion is drawn from the sample to carry out the measurement. Obviously, this test portion must be representative of the
sample, otherwise the certified value is still not applicable. Both kinds of homogeneity tests are examined in the paper and
evaluated using practical examples.
Received: 31 May 2000 · Accepted: 29 July 2000 相似文献
874.
Microbiological analyses are carried out on clinical, food, feed and environmental samples. The aims of the analyses are diagnostic
or estimation of the safety or the quality of the sample. Important decisions are made on the basis of microbiological analyses.
Little attention, however, is paid to the uncertainty of measurement of microbiological analyses. In microbiological cultivation
techniques the result is obtained by counting individual objects. The normally low number of counted objects strongly affects
the result of the analysis and its uncertainty. Because of the importance of the particle statistical variation to the uncertainty,
the approaches developed for chemical analyses are not directly applicable to microbiology. This paper discusses microbial
analyses and describes a novel guidance document for the estimation of measurement uncertainty in culturing methods [1].
Received: 7 October 2000 Accepted: 8 March 2001 相似文献
875.
Walter Bich 《Accreditation and quality assurance》2009,14(7):389-392
A recent paper by Nam et al. (Accred Qual Assur 14:43–47, 2009) considers the issue of repeated measurements of a same measurand.
The paper is a follow-up of two previous papers (Choi et al. in Accred Qual Assur 8:13–15, 2003, 8:205–207, 2003) on the
same topic. The first two papers show a well-known fact, i.e., that systematic effects are not reduced by repeating measurements,
and give formulae for the uncertainty of the estimate of the average from repeated measurements in the case that the differences
between individual results are not (Choi et al. in Accred Qual Assur 8:13–15, 2003) or are (Choi et al. in Accred Qual Assur
8:205–207, 2003) statistically significant, respectively. The last paper addresses a more interesting issue, that is, a difference
in the estimate average for non-linear models depending on how raw data is processed in the model. In the present paper, I
re-discuss the whole issue of multiple measurements, trying to clarify the various aspects of the topic.
Papers Published in this section do not necessarily reflect the opinion of the Editors, the Editorial Board, and the Publisher. 相似文献
876.
To achieve a competitive edge needed for marketing highly competitive products, modern enterprises have actively sought to provide the marketplace with an expansive range of products with high random volatility of demand and correlations between demands of product. Consequently, traditional forecasting methods for separately forecasting demand for these products are likely to yield significant deviations. Therefore, this study develops a real options approach-based forecasting model to accurately predict future demand for a given range of products with highly volatile and correlated demand. Additionally, this study also proposes using Monte Carlo simulation to solve the demand forecasting model. The real options approach associated with Monte Carlo simulation not only deals effectively with random variation involving a particular demand stochastic diffusion process, but can handle the correlations in product demand. 相似文献
877.
878.
The quantum correspondence of the very peculiar phenomenon of classical chaos-the exponential instability of motion can be characterized by the initially exponential growth rate of the total uncertainty measurement of the propagating quantum wave packet. Our calculation indicates that quantitatively the growth rate is approximately twice the classical maximum Lyapunov exponent of the system. 相似文献
879.
Entropy squeezing for a two-level atom in the Jaynes-Cummings model with an intensity-depend coupling 总被引:1,自引:0,他引:1
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We study the squeezing for a two-level atom in the Jaynes-Cummings model with intensity-dependent coupling using quantum information entropy, and examine the influences of the initial state of the system on the squeezed component number and direction of the information entropy squeezing. Our results show that, the squeezed component number depends on the atomic initial distribution angle, while the squeezed direction is determined by both the phases of the atom and the field for the information entropy squeezing. Quantum information entropy is shown to be a remarkable precision measure for atomic squeezing. 相似文献
880.
Higher-order squeezing of quantum electromagnetic fields and higher-order uncertainty relations in two-mode squeezed states
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It is found that the two-mode output quantum electromagnetic field in two-mode squeezed states exhibits higherorder squeezing to all even orders, and the degree of higher-order squeezing is greater than that of the second-order.The higher-order squeezed parameter and squeezed limit due to the modulation frequency are investigated. The smaller the modulation frequency is, the stronger the degree of higher-order squeezing becomes. Furthermore, the higher-order uncertainty relations in two-mode squeezed states are presented for the first time. The product of higher-order noise moments is related to even order number N and the squeeze factor r. 相似文献