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1.
The sensitivity of a monitoring scheme depends on many factors including the variance of the charting statistic which is very important in the computation of the control limits. This paper discusses the computation of the variance of the recently proposed hybrid homogeneously weighted moving average (HHWMA) X¯ scheme which was based on an incorrect assumption. The correct variance is used to evaluate the run-length characteristics of the HHWMA X¯ scheme. It is observed that the incorrect variance has a significant impact on the sensitivity (or performance) of the HHWMA X¯ scheme.  相似文献   
2.
A thermodynamic modeling of GaN was carried out to describe the thermodynamic behavior of native defects, dopants, and carriers (free electrons and holes) in GaN semiconductors. The compound energy model (CEM) was used. An unintentionally doped GaN was taken as an example. Oxygen was introduced into the model as the unintentionally doped impurity, according to the practical experimental phenomena. The energies of component compounds in the model were defined based on the results of the ab initio calculations and adjusted to fit experimental data. The thermodynamic properties of the defects and the oxygen doped were calculated to show the facility of the model.  相似文献   
3.
4.
Reviews the predominant models developed by researchers to assess the psychological adaptation of immigrants in the host society. The use of the terms assimilation and acculturation to reflect the process of change undergone by immigrants is discussed. Although these terms have been used interchangeably, the outcome of change is very different in each. The difference between assimilation and acculturation is reflected in the models of adaptation regrouped under linear and bidimensional models. A 3rd model, called orthogonal cultural identification, is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Different modes of activation are described for a postgrafting reaction of acrylic acid on poly(p-phenylene terephthalamid) (PPTA)mitrogen plasma or electron-beam irradiation. Both lead to surface radical formation, and these species are able to initiate grafting. The Functionalization through amino group attachment is characteristic of plasma treatment. Degradation initiated by UV-visible emission of plasma is noticed, leading to the amide clivage. The surface grafting is more important when the PPTA is irradiated with a cold plasma and if water is used as the solvent. The polymer crystallinity degree reduces the grafting of the electron beam-irradiated PPTA even with a high radical concentration. © 1994 John Wiley & Sons, Inc.  相似文献   
6.
Biphasic and nth-order models were tested as to their usefulness to fit experimental inactivation data of Bacillus licheniformis α-amylase, immobilized on glass beads, and were discussed with respect to their suitability to characterize the considered enzymic system as a time—temperature integrator (TTI) to evaluate heat processes. Both isothermal and non-isothermal inactivation experiments were carried out. Model (kinetic) parameters (rate constant k, activation energy EA and reaction order n) were estimated using a non-linear regression procedure. The results obtained, especially the activation energy of about 293 kJ mole–1, indicated a potential use of this system as a TTI for heating processes in the temperature range of 96–108°C.  相似文献   
7.
A study of the prevalences of Salmonella, Listeria and thermophilic campylobacters in a dedicated commercial poultry feed mill was undertaken. Salmonella was frequently recovered in samples taken in the preheat and postheat treatment areas of the mill with the overall percentage of samples positive found to be 18.8% and 22.6%, respectively. Feed ingredients and dust collected in the preheat treatment locations within the mill were frequently contaminated with Salmonella (11.8% and 33.3% of samples, respectively). High prevalences of Salmonella were also detected in dust samples (24.2%) obtained from the postheat treatment area of the mill and from feed delivery vehicles (57.1%).
Listeria was also recovered from samples at pre- and postheat treatment areas within the mill with overall isolation rates of 14.1% and 18.5% observed, respectively. The most frequently observed species of Listeria recovered from samples in both areas within the mill was L. innocua, L. monocytogenes, L. grayi and L. welshimeri.
No thermophilic campylobacters were recovered from any of the samples analyzed in the current study.  相似文献   
8.
The underlying property, its definition, and representation play a major role when monitoring a system. Having a suitable and convenient framework to express properties is thus a concern for runtime analysis. It is desirable to delineate in this framework the sets of properties for which runtime analysis approaches can be applied to. This paper presents a unified view of runtime verification and enforcement of properties in the Safety-Progress classification. First, we extend the Safety-Progress classification of properties in a runtime context. Second, we characterize the set of properties which can be verified (monitorable properties) and enforced (enforceable properties) at runtime. We propose in particular an alternative definition of ??property monitoring?? to the one classically used in this context. Finally, for the delineated sets of properties, we define specialized verification and enforcement monitors.  相似文献   
9.
Solubilities and diffusivities of carbon dioxide and nitrous oxide in a mixture of toluene and isopropanol organic solution of cyclohexylamine were measured at 20°C in the range of pressures of solute from 1 to 3 bars. This was performed with an original chromatographic technique taking into account the presence of the product of the reaction.  相似文献   
10.
Structural Aspects of the Lattice Thermal Expansion of Hexagonal Cordierite   总被引:3,自引:0,他引:3  
The mechanism of lattice thermal expansion in pure hexagonal cordierite prepared by glass devitrification was investigated by time-of-flight neutron powder diffraction at temperatures from 22° to 750°C under vacuum. Full matrix least-squares refinement of the diffraction spectra was carried out in space group P6/mcc using the Rietveld method. The structural data from the refinements were resolved into components parallel and normal to the c axis. The negative c axis expansion results from two effects: (1) increasing distortion of the T2 tetrahedral (ring tetrahedra) with temperature, primarily due to displacement of the T2 cations toward the c-axis channels in the structure; (2) decreasing distortion of the T1/M tetrahedra/ octahedra with increasing temperature, due to octahedral I (M-O1) bond expansion and an associated decrease in torsional distortion of the T1 tetrahedra.  相似文献   
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