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91.
Bakermans-Kranenburg M. J.; van Uzendoorn M. H.; Bokhorst C. L.; Schuengel C. 《Canadian Metallurgical Quarterly》2004,18(3):545
In this first behavior genetic study on infant-father attachment, we estimated genetic and environmental influences on infant-father attachment behaviors and on temperamental dependency, both assessed with the Attachment Q-Sort (AQS; B. E.Vaughn & E. Waters, 1990; E. Waters, 1995). Mothers of mono- and dizygotic twins (N = 56 pairs) sorted the AQS with a focus on the infant's behaviors in the presence of the father. Genetic modeling showed that attachment was largely explained by shared environmental (59%) and unique environmental (41%) factors. For dependency, genetic factors explained 66% of the variance, and unique environmental factors including measurement error explained 34%. Attachment to father appears to be, to a significant degree, a function of the environment that twins share. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
以材料的力学性能分析为基础,利用双界限系数将碳纤维增强混凝土受弯构件划分成三种正截面的破坏形态,对每一种破坏形态,建立了单、双筋矩形截面极限承载力的计算式,使碳纤维增强混凝土构件正截面计算与现行的规范相一致。 相似文献
93.
V Živica 《Bulletin of Materials Science》1995,18(2):115-124
The paper describes a method for the mathematical modelling of steel reinforcement corrosion rate. This method is based exclusively
on experimental results and expression of the influence of significant corrosion factors in the form of functional relations.
The method takes into account the reality of the effects of corrosion factors, their contigency and complexity, and various
circumstances occurring in practice. It represents one way towards the development of methods for the prediction of service
life of reinforced concrete and structures. 相似文献
94.
秦家浩 《青岛大学学报(工程技术版)》1991,(1)
九十年代是中国社会主义现代化建设进程的关键时期。作者从宏观角度提出了青岛市如何进一步增强整体开放意识,开创对外开放工作的设想。对我市今后更好适应我国的经济振兴和社会进步意义重大。 相似文献
95.
文章介绍了目前国内外长输管道外防护技术的特点和防护层应用的现状,分析了常用防腐蚀材料的防腐蚀性能。指出在山区复杂地形条件下,应考虑环境条件和施工条件,并通过技术经济分析对管道外防腐蚀层进行合理选择。 相似文献
96.
Strength reduction factors (SRFs) continue to play a key role in obtaining design forces from elastic design spectra (via
response modification factors) in ductility-based earthquake-resistant design. Despite several years of sustained research
efforts, it has not been conclusively shown how SRF for a given singledegree-of-freedom structural system depends on various
source and site parameters. A parametric study is carried out here for the explicit dependence of SRF spectrum (describing
variation of SRF with system period for a given ductility demand) on strong motion duration, earthquake magnitude, geological
site conditions, and epicentral distance in case of (non-degrading) elasto-plastic oscillators. For this, scaled response
spectra are considered for different combinations of earthquake magnitude, site conditions and epicentral distance, and SRF
spectra are generated from 1274 accelerograms recorded in western USA after making those compatible with each of these spectra.
It is shown that there is no clear and significant dependence of SRF spectrum on strong motion duration. Further, the parametric
dependence on earthquake magnitude, site conditions, and epicentral distance broadly conforms to the trends reported by earlier
investigations. In particular, this study confirms that the dependence of SRF spectra on earthquake magnitude should not be
ignored.
This paper has been contributed in honour of Professor R N Iyengar, Indian Institute of Science, on the occasion of his formal
retirement. 相似文献
97.
沁水煤田瓦斯含量与地质因素的关系 总被引:1,自引:0,他引:1
为确实做好瓦斯的洲报工作,研究了沁水煤田地质因素与瓦斯含量的关系,辩证地分析了瓦斯的赋存规律。 相似文献
98.
Yu. F. Smirnov 《Measurement Techniques》2007,50(3):293-297
Metrological characteristics of active hydrogen frequency standards are investigated on the basis of internal and external
comparisons. The stability of random changes and drift of hydrogen frequency standards and also the potential capabilities
of time scale preservation with effective consideration of systematic changes in their frequency are demonstrated.
__________
Translated from Izmeritel’naya Tekhnika, No. 3. pp. 42–45, March, 2007. 相似文献
99.
In their comments on the authors' article (see record 2003-10163-009), R. C. Serlin, B. E. Wampold, and J. R. Levin (see record 2003-10163-011) and P. Crits-Christoph, X. Tu, and R. Gallop (see record 2003-10163-010) took issue with the authors' suggestion to evaluate therapy studies with nested providers with a fixed model approach. In this rejoinder, the authors' comment on Serlin et al's critique by showing that their arguments do not apply, are based on misconceptions about the purpose and nature of statistical inference, or are based on flawed reasoning. The authors also comment on Crits-Christoph et al's critique by showing that the proposed approach is very similar to, but less inclusive than, their own suggestion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
为了改善筛分机械的使用环境,降低筛分机械的噪声,从噪声源入手,从内因和外因两个方面分析了筛分机噪声的形成原因。论述了USL和USK系列振动筛在降低噪声方面所采取的先进技术措施。 相似文献