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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.
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   
4.
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   
5.
四株狂犬病街毒的免疫学特性   总被引:1,自引:0,他引:1  
目的 研究国内分离的4株狂犬病街毒的免疫学特性。方法 采用免疫力试验及中和试验进行抗原性及免疫原性检测。结果4株街毒抗原性存在一定差异,应用aG株疫苗免疫小鼠能保护4株街毒的攻击。结论aG疫苗与4株街毒具有良好的交叉免疫性。  相似文献   
6.
新城金矿采场落矿控制爆破技术   总被引:1,自引:1,他引:0  
李风山  王书宣 《黄金》1991,12(1):28-32
新城金矿为蚀变岩型金矿床,由于受地质构造影响,顶板稳定性较差,局部和较大面积的顶板冒落现象时有发生,为了解决采场顶板安全问题和提高落矿主要技术经济指标而进行了“上向水平分层尾砂胶结充填法采场控制爆破技术”的试验研究工作,试验达到了预期效果。  相似文献   
7.
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   
8.
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   
9.
A film of cellulose acetate was submitted to a cold plasma of tetrafluoromethane or of sulfur hexafluoride. The interactions of these cold plasmas and cellulose acetate lead to a material whose surface has been modified by fluorination. Comparison of CF4 or SF6 plasma treatment shows that fluorine atoms provided by each kind of plasma induce degradation and grafting of fluorocarbon radicals on the surface. As a consequence, the surface energy decreases and offers the possibility of a better response of plasma-modified cellulose derivatives used as biomaterials (e.g. hemodialysis membrane).  相似文献   
10.
In the present paper, a strategy for solving transient thermoviscoplastic problems is described. The general thermal and mechanical coupling phenomena are discussed by assuming material properties to be temperature-dependent and accounting for the mechanical terms in the non-stationary heat conduction equation. Time integration is carried out with an implicit scheme. An interesting version of the three-field approach is presented to obtain an accurate solution for the stress field. Finally, a global product coupling algorithm, in which the unknown nodal velocities and temperatures are solved with a two-step solution procedure is suggested. The proposed fractional step method partitions the initial coupled problem into an isothermal viscoplastic problem followed by a purely heat conduction problem at fixed configuration. Applications in metal forming analyses involving full thermomechanical coupling conclude the paper.  相似文献   
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