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21.
Burns John W.; Kubilus Amanda; Bruehl Stephen; Harden R. Norman; Lofland Kenneth 《Canadian Metallurgical Quarterly》2003,71(1):81
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
指出当今建筑业良好的市场给建筑师们提供了展示自己作品的广大空间 ,但其精品却为之甚少。为此 ,对建筑业存在的一些问题及制约建筑师出精品的主、客观因素进行了分析 ,指出建筑师应提高自身素质 ,树立精品意识 ,增强市场竞争能力 相似文献
23.
已二醇二丙烯酸酯对真丝的接枝改性研究 总被引:2,自引:0,他引:2
研究了用二醇二丙烯酸酯为接枝单体、过硫酸铵(APS)为引发剂对真丝的接枝共聚反应,分析了接枝率的影响素,并测试了改性真丝的主要应用性能。结果表明:乳液和乙醇/水为溶剂的2种体系都能在真丝上获得较高接枝率。对于乙醇/水体系v(乙醇):v(H2O)=1:1,接枝单体20~30g/L,2%甲酸4ml,引发剂APS 0.5g/L,65~70℃接枝60min的接枝率高。改性后真丝的断裂强度、延伸度、吸湿性能都可获得改善,对酸、碱的溶解性提高,但染色性能提高不明显,对泛黄性改善一般。 相似文献
24.
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
25.
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
26.
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
27.
The successful initiation and execution of a virtual team is gaining increasing attention in the design and construction community. From opportunities to integrate international and multidisciplinary teams to the opportunity to leverage the best resources in an organization on a given project, virtual teams can transform the concept of project planning and execution. However, potential barriers exist in several areas to the successful implementation of virtual teams. The needs of increased management emphasis, social and cultural understanding, and emphasis on common goals are only a few of the nontechnical factors that can turn successful virtual teaming into virtual frustration. When combined with traditional technical challenges including compatibility of systems, security, and the selection of appropriate technologies, the line between leveraging virtual technologies for enhanced solutions and introducing additional complications into the project process is one that can be easily crossed. This paper presents the findings of research that addresses the opportunities and potential barriers to successful virtual teams in the engineering, procurement, and construction industry. Combining results from current research, industry practices, and early results from nonconstruction industries, the research findings provide an initial path to successful virtual team implementation. 相似文献
28.
Capital cost correlations are given for oil-water separators, equalization basins, primary clarifiers, clarifiers and clarifier mechanisms, reverse osmosis unit, ultrafiltration units, gravity filters and miroscreens. Data are included for raw sewage, intermediate and recirculation pumping stations and for preliminary treatment (or bar screens, grit removal, overflow and bypass chamber and Parshall flume), for grit removal, comminution and gas stripping. The correlations are accurate to ± 30%, expressed in Canadian dollars and adjusted to a Marshall and Swift value of 1000. Details as to what components are included in the cost are given. Data are given for the labour and material costs to create a working process module. For inflation indices, a critique of the Engineering News Record, EPA small city, Marshall and Swift, Chemical Engineering and Southam inflation indices suggested that the Marshall and Swift index is most appropriate for the construction and process equipment studied here. Concerning the currency exchange, for the equipment and processes in this study, equipment costs the same whether expressed directly in US or Canadian dollars. To put the current data into perspective, several hundred sources of cost data were analyzed. The major correlations are compared, on a consistent basis, with current data. 相似文献
29.
近年来,随着创新性技术的不断应用,硬盘驱动器的气膜浮动块(以下简称浮动块)也有了较大改进,例如浮动块表面的设计越来越精巧,而性能却更加稳定。因此很好的理解哪些因素是影响气膜浮动块浮动特性的主要原因显得尤为重要。分析这些因素对浮动块的影响结果,有利于我们改进浮动块的特性并对其发展前景做出预测,本文对这些影响因素做了概括总结。 相似文献
30.
通过有限元的方法,分析了T型薄壁管节点受平面内弯矩作用下的疲劳行为,得到了应力最大值的位置和拟合出用于预测T型薄壁管节点受平面内弯矩作用下的应力集中系数的参数公式。 相似文献