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81.
O'Connell Kathleen A.; Gerkovich Mary M.; Bott Marjorie J.; Cook Mary R.; Shiffman Saul 《Canadian Metallurgical Quarterly》2002,16(2):150
The authors tested a model hypothesizing the predictors and the effects of anticipatory strategy use on the 1st day of smoking cessation using data from 63 participants in an ecological momentary assessment study of smoking cessation. Remaining abstinent on the 1st day of cessation was not associated with mean level of urges to smoke during tempting situations but was associated with anticipatory strategy use, which accounted for 18% of the variance. Getting rid of cigarettes contributed the most to this effect (β?=?-.397). Getting rid of cigarettes was itself predicted by 2 variables, lower nicotine dependence (β?=?-.264) and attending a formal smoking cessation class (β?=?.305), which accounted for 15% of its variance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Peeters Frenk; Nicolson Nancy A.; Berkhof Johannes; Delespaul Philippe; deVries Marten 《Canadian Metallurgical Quarterly》2003,112(2):203
Major depressive disorder (MDD) is characterized by high negative affect (NA) and low positive affect (PA), but little is known about emotional reactivity in daily life. The authors used experience sampling methodology to investigate changes in NA and PA following minor daily events in MDD compared with healthy participants. Contrary to expectation, MDD participants did not report more frequent negative events, although they did report fewer positive events. Multilevel regression showed that both NA and PA responses to negative events were blunted in the MDD group, whereas responses to positive events were enhanced. NA responses to negative events persisted longer in MDD participants. Depressed participants with a positive family history or longer current episodes showed relatively greater NA responses to negative events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
结合典型爆破工程,回顾了我国工程爆破自20世纪50年代以来的发展历史,将其总结为"起步、成长、壮大"三个阶段,简要介绍了各阶段工程爆破基础理论、工程实践、科学研究和行业组织的主要成果。并对我国工程爆破行业未来的发展方向进行了展望。 相似文献
84.
《International Journal of Hydrogen Energy》2022,47(62):25913-25928
The high flammability of hydrogen gas gives it a steady flow without throttling in engines while operating. Such engines also include different induction/injection methods. Hydrogen fuels are encouraging fuel for applications of diesel engines in dual fuel mode operation. Engines operating with dual fuel can replace pilot injection of liquid fuel with gaseous fuels, significantly being eco-friendly. Lower particulate matter (PM) and nitrogen oxides (NOx) emissions are the significant advantages of operating with dual fuel.Consequently, fuels used in the present work are renewable and can generate power for different applications. Hydrogen being gaseous fuel acts as an alternative and shows fascinating use along with diesel to operate the engines with lower emissions. Such engines can also be operated either by injection or induction on compression of gaseous fuels for combustion by initiating with the pilot amount of biodiesel. Present work highlights the experimental investigation conducted on dual fuel mode operation of diesel engine using Neem Oil Methyl Ester (NeOME) and producer gas with enriched hydrogen gas combination. Experiments were performed at four different manifold hydrogen gas injection timings of TDC, 5°aTDC, 10°aTDC and 15°aTDC and three injection durations of 30°CA, 60°CA, and 90°CA. Compared to baseline operation, improvement in engine performance was evaluated in combustion and its emission characteristics. Current experimental investigations revealed that the 10°aTDC hydrogen manifold injection with 60°CA injection duration showed better performance. The BTE of diesel + PG and NeOME + PG operation was found to be 28% and 23%, respectively, and the emissions level were reduced to 25.4%, 14.6%, 54.6%, and 26.8% for CO, HC, smoke, and NOx, respectively. 相似文献
85.
针对业主现场代表的综合素质与工作方法进行了探讨,指出业主现场代表应具备丰富的工程阅历和经验,管理施工现场能统筹兼顾,具有良好的沟通协调能力,并掌握科学的管理方法与措施,才能将建设项目管理好。 相似文献
86.
针对在执行GB/T 482—2008《煤层煤样采取方法》时遇到的特殊情况,提出了易于操作的具体方法,并建议在标准中应有备注说明或另行要求。 相似文献
87.
姚廷璋 《地下空间与工程学报》1992,(1)
平原城市由于地质情况,多层建筑用条形基础时一般挖深都在3.0米左右,按上级文件此深度(含桩基)应修建满堂红地下室,战时作防空使用。但这一条一般未得到贯彻。宁肯打桩不愿搞地下室的原因主要是:(1)工期增长;(2)投资增大;(3)平时不好用,本文试对上述问题提出几点建议。 相似文献
88.
“数字差距”不是个别国家,个别地区的独有现象,而是一个全球性的问题,缩小全球范围内的“数字差距”,应当建立在对旧的世界经济秩序革新的基础上,改革开放20多年来,中国电信业已由制约经济发展的“瓶颈”,发展成为带动经济增长的先导产业,支柱产业和战略产业,电信服务普及率也达到了一个空前的高度,但由于各方面的原因,中国东西部之间还存在较大的差距,偏远地区电信发展也还面临很多困难,为此,中国政府和企业还有很多工作要做。 相似文献
89.
ABSTRACT: Images (for example, photomicrographs) are routinely used as qualitative evidence of the microstructure of foods. In quantitative image analysis it is important to estimate the area (or volume) to be sampled, the field of view, and the resolution. The bootstrap method is proposed to estimate the size of the sampling area as a function of the coefficient of variation (CV Bn ) and standard error (SE Bn ) of the bootstrap taking sub-areas of different sizes. The bootstrap method was applied to simulated and real structures (apple tissue). For simulated structures, 10 computer-generated images were constructed containing 225 black circles (elements) and different coefficient of variation (CV image ). For apple tissue, 8 images of apple tissue containing cellular cavities with different CV image were analyzed. Results confirmed that for simulated and real structures, increasing the size of the sampling area decreased the CV Bn and SE Bn . Furthermore, there was a linear relationship between the CV image and CV Bn . For example, to obtain a CV Bn = 0.10 in an image with CV image = 0.60, a sampling area of 400 × 400 pixels (11% of whole image) was required, whereas if CV image = 1.46, a sampling area of 1000 × 100 pixels (69% of whole image) became necessary. This suggests that a large-size dispersion of element sizes in an image requires increasingly larger sampling areas or a larger number of images. 相似文献
90.
Presents the report of the Canadian Psychological Association Representative to the Social Science Research Council of Canada. The Annual Meeting of the Social Science Research Council of Canada met at Carleton University on 13 June 1967. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献