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81.
Galatzer-Levy Isaac R.; Mazursky Heather; Mancini Anthony D.; Bonanno George A. 《Canadian Metallurgical Quarterly》2011,25(3):384
A recent article in New York Magazine echoed what psychological studies of parenthood have consistently demonstrated since the 1970s: “Most people assume that having children will make them happier. Yet a wide variety of academic research shows that parents are not happier than their childless peers, and in many cases are less so” (Senior, 2010). There is consistent evidence that, as opposed to other life events that cause transient disruptions in life satisfaction, becoming a parent appears to cause harm to individual subjective well-being (Twenge, Campbell, & Foster, 2003), and that this harm is sustained over time (Clark, Diener, Georgellis, & Lucas, 2008). The current investigation was predicated on the concern that these findings may be the result of the methodology used to examine them. As the experience of parenthood does not represent a unified phenomenon, we employed a methodological approach that allows for the exploration of heterogeneity as well as its predictors. By modeling heterogeneous trajectories within a prospective design from 4 years prior to 4 years after the birth of a parent's first child, we find that the majority of individuals (84.2%) demonstrate no long-term effects on life satisfaction in response to childbirth. Only a small percentage demonstrate the sustained declines (7.2%), and a significant cohort, previously unobserved in the literature, demonstrate dramatic and sustained improvements in response to parenthood (4.3%), providing compelling evidence for heterogeneity in life satisfaction among parents. Key demographic covariates that distinguish between trajectories of response are also explored. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
82.
总结了军事综合电子信息系统试验的特点和分类,提出了军事电子信息系统试验分六个阶段的试验流程,针对每个试验阶段,从主要任务、主要活动和完成标准三个方面做了较深入的分析,并给出了合理组织试验六个阶段的并行试验过程模型。 相似文献
83.
Advanced nuclear water reactors rely on containment behaviour in realization of some of their passive safety functions. Steam condensation on containment walls, where non-condensable gas effects are significant, is an important feature of the new passive containment concepts, like the AP600/1000 ones.In this work the international reactor innovative and secure (IRIS) was taken as reference, and the relevant condensation phenomena involved within its containment were investigated with different computational tools. In particular, IRIS containment response to a small break LOCA (SBLOCA) was calculated with GOTHIC and RELAP5 codes. A simplified model of IRIS containment drywell was implemented with RELAP5 according to a sliced approach, based on the two-pipe-with-junction concept, while it was addressed with GOTHIC using several modelling options, regarding both heat transfer correlations and volume and thermal structure nodalization. The influence on containment behaviour prediction was investigated in terms of drywell temperature and pressure response, heat transfer coefficient (HTC) and steam volume fraction distribution, and internal recirculating mass flow rate. The objective of the paper is to preliminarily compare the capability of the two codes in modelling of the same postulated accident, thus to check the results obtained with RELAP5, when applied in a situation not covered by its validation matrix (comprising SBLOCA and to some extent LBLOCA transients, but not explicitly the modelling of large dry containment volumes).The option to include or not droplets in fluid mass flow discharged to the containment was the most influencing parameter for GOTHIC simulations. Despite some drawbacks, due, e.g. to a marked overestimation of internal natural recirculation, RELAP5 confirmed its capability to satisfactorily model the basic processes in IRIS containment following SBLOCA. 相似文献
84.
计算机辅助正交设计技术以VB6.0作为开发工具,采用面向对象的设计方法进行开发。它可以帮助用户安排正交和实现材料试验过程中的数据处理(包括极差分析和方差分析)。同时,也可以应用于其他行业的正交试验数据处理。 相似文献
85.
Miniaturisation and parallelisation are fundamental strategies to enable the productivity improvements achievable by high-throughput
experimentation (HTE). This paper reports how the approach has been used to allow robotic preparation of supported precious
metal catalysts and parallel techniques for subsequent reaction testing. It will be shown how HTE can shorten catalyst development
times through increased productivity, as well as enabling a greater diversity space to be explored than would otherwise occur.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
86.
影响蓝宝石抛光去除率的因子有很多,为了得到最佳工艺流程和工艺参数组合,实际工作中需要在诸多影响因素中找出对去除率影响最显著的因子,并以拟合方程的形式来建立数学模型。探讨了运用正交试验的方法,通过MINITAB软件对试验数据进行分析,从而了解各抛光参数对抛光去除率的影响,最终确定一组最优的工艺参数。 相似文献
87.
在实际水下目标跟踪系统中,由声纳获得的速度量测是一个相对径向速度,并且量测噪声是非白的,为此提出了基于扩展量测和扩展状态的混合坐标系下水下目标跟踪算法。该方法把径向速度量测引入观测模型,提高了目标的状态估计精度和收敛时间;引入了扩充向量,克服了实际水下目标观测噪声非白的影响。提出了水下多目标跟踪水池试验方法。该方法应用静态长线阵和多目标信号源在水池实现了多目标和跟踪体之间的相对运动的模拟。水池试验结果表明所提出的方法性能明显优于基于量测转换跟踪方法(如MC方法),具有重大工程应用价值。 相似文献
88.
Q. Charlier J. Viguié B. Harthong J.-B. Toni M. Terrien D. Imbault R. Peyroux 《Materialwissenschaft und Werkstofftechnik》2021,52(8):891-906
Ultrasonic welding is a serious candidate in the development of methods to assemble papers and paperboards without using additional substances. However, the ultrasonic welding of papers remains a technological challenge considering the low weldability of lignocellulosic materials. This study aims to investigate on the ultrasonic welding process applied to papers in order to identify the processing conditions which favor the formation of strong welded joints. To reach such purpose, an experimental strategy was developed by combining the characterization of welded materials and the monitoring of process parameters. Experimentations were performed using a reference paper displaying a good weldability to specifically highlight the contribution of process parameters. Results indicate that the process is highly sensitive to vibration amplitude, power supplied by the high frequency generator, and sample thickness. Power seems to be a reliable indicator of the severity of the process. A strong decrease in the strength of the welded joints is observed when working with low thicknesses. It seems that the layers coated on top of papers are the main part of the material contributing in the development of adhesion at the welding joint. Overall, instrumenting the device has led to a better understanding of the ultrasonic welding of papers. 相似文献
89.
90.