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排序方式: 共有675条查询结果,搜索用时 15 毫秒
1.
2.
Jean-Claude Malela-Majika Sandile Charles Shongwe Olatunde Adebayo Adeoti 《Quality and Reliability Engineering International》2021,37(8):3314-3322
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) scheme which was based on an incorrect assumption. The correct variance is used to evaluate the run-length characteristics of the HHWMA scheme. It is observed that the incorrect variance has a significant impact on the sensitivity (or performance) of the HHWMA scheme. 相似文献
3.
Pierre Santucci Christina Dedaki Alexandros Athanasoulis Laura Gallorini Anaïs Munoz Dr. Stéphane Canaan Dr. Jean-François Cavalier Dr. Victoria Magrioti 《ChemMedChem》2019,14(3):349-358
In the quest for new antibacterial agents, a series of novel long- and medium-chain mono- and disubstituted β-lactones was developed. Their activity against three pathogenic mycobacteria—M. abscessus, M. marinum, and M. tuberculosis—was assessed by the resazurin microtiter assay (REMA). Among the 16 β-lactones synthesized, only 3-hexadecyloxetan-2-one (VM005) exhibited promising activity against M. abscessus, whereas most of the β-lactones showed interesting activities against M. marinum, similar to that of the classical antibiotic, isoniazid. Regarding M. tuberculosis, six compounds were found to be active against this mycobacterium, with β-lactone VM008 [trans-(Z)-3-(hexadec-7-en-1-yl)-4-propyloxetan-2-one] being the best growth inhibitor. The promising antibacterial activities of the best compounds in this series suggest that these molecules may serve as leads for the development of much more efficient antimycobacterial agents. 相似文献
4.
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
5.
众所周如,西藏地区是研究地球深部结构和构造的窗口,是研究大陆板块学说的重要场所,也是寻找热源和其它矿产资源的有利地区.因此,世界各国地学科学家都希望在本地区进行科学研究工作,或与我国科学工作者协作共同探索这一重要地区.中国和法国的地质、地球物理科学家经商讨共同组成“中法喜马拉雅山地质研究队”,对西藏中部广大地区进行地质、地球物理的科学研究工作.深部地震探测是地球物理研究中的重要内容.中法双方共同决定,在中国西藏南部的日喀则地区至北边的那曲地区作地震探测工作.为了探测地壳上地幔的结构,1981年在西藏的南部佩枯错至普莫雍错500公里的喜马拉雅山北麓——雅鲁藏布江地区进行了人工爆炸地震探测工作.本文是中法地质研究队合作的深部地震探测资料的解释结果. 相似文献
6.
We propose an on-line learning algorithm for Multi Layered Perceptrons (MLP) with an Orthogonal Weight Estimator (OWE) architecture. Such an architecture allows to dynamically and efficiently estimate the weights of a MLP in context dependent behaviour problems. The proposed learning algorithm attempts to solve the problem of time-consuming in the learning phase encountered to train these weight estimators. 相似文献
7.
J Salmon D Levêque JD Peter A Cavalier H Elkha?li Y Salmon G Kaltenbach H Monteil F Jehl 《Canadian Metallurgical Quarterly》1996,44(5):375-378
The purpose of this study was to examine the role of sleep problems in the etiology of nursing caries. Two-hundred mothers of children (104 with nursing caries and 96 caries free) from ages 2 to 4.5 years were surveyed to determine whether difficulty with child sleep and ensuing sleep-associated feeding might be related to the presence of nursing caries. Differences were noted between these two groups regarding: average number of nights the child slept through the night (P < 0.001); total hours of sleep per night (P < 0.05); frequency of night waking episodes (P < 0.01); feeding on demand upon waking (P < 0.01); using a bottle to assist with falling asleep at night (P < 0.001); and feeding in association with nap time (P < 0.001). Differences also were noted in regard to average age of weaning (P < 0.001). Our findings suggest that sleep problems among young children are a behavioral risk factor for night-time bottle use and early childhood caries. 相似文献
8.
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
9.
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
10.
Najim Selhaoui Jean-Claude Gachon Jean Hertz 《Metallurgical and Materials Transactions B》1992,23(6):815-819
In the course of a systematic study of binary transition metal alloys, the enthalpies of formation of five Hf-Ni compounds
were measured by direct reaction calorimetry: Hf0.17Ni0.83(l/6HfNi5): ΔfH(1323 K) = − 37,000 J/mole of atoms (±3200) Hf0.22Ni0.781/9Hf2Ni7): Δf(1623 K) = −50,700 J/mole of atoms (±2000) Hf0.45Ni0.55(l/2OHf9Ni11): ΔfH(1473 K) = −54,500 J/mole of atoms (±2200) Hf0.50Ni0.50(l/2HfNi): ΔfH(1573 K) = −47,900 J/mole of atoms (±1800) Hf0.67Ni0.33(l/3Hf2Ni): ΔH(1423 K) = −36,700 J/mole of atoms (±1300) with reference to pure metals in their equilibrium states at the reaction
temperatures. The Ni-rich Hf-Ni liquid was also studied by the dissolution of Hf in the liquid alloy of variable composition
at 1743 and 1633 K. Results show that the enthalpy of formation of the liquid at a given composition depends strongly on temperature,
and this point suggests the existence of associations in the liquid. The melting temperature of Hf0.22Ni0.78(Hf2Ni7) which was found (1705 K) is slightly lower than the one (1743 K) given in the literature.
Formerly Senior Research Student with the Laboratoire de Thermodynamique Métallurgique, Université de Nancy Un, France 相似文献