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81.
本工程在混凝土浇筑上采用新工艺并结合主体交叉作业方式,通过具体施工完善了设计。  相似文献   
82.
与传统正投影显微图像分析方法不同,本文应用斜投影法,通过变换观测颗粒群的角度,依据获得的光学显微镜下颗粒群的信息,推导出了颗粒群厚度的计算公式,并讨论了厚度分辨能力与倾斜角、放大倍数之间的关系,同时应用实例证明了该方法的可行性。  相似文献   
83.
叶松涛 《工具技术》2012,46(3):48-49
对于零件弯道的两个3空间斜孔,原通过组合夹具定位后,采用划线加工,加工质量不能满足图纸要求。针对该问题,指出了划线加工的不足,并采用新的加工方法,即在立卧转换加工中心上,开发并运用其潜在的"循环19(即零点跟踪)"功能,从而显著提高了整机的性能。  相似文献   
84.
软岩溜煤立眼的施工。(1)此立眼全部在岩层中施工,(2)、溜煤立眼采用料石支护,(3)、立眼料石支护与混凝土相比,施工中减少了支模工序,(4)节省了投资,保证安全施工效果良好。  相似文献   
85.
Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals’ intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2 × 2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N = 151), aged 17–30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal.  相似文献   
86.
《国际计算机数学杂志》2012,89(3-4):175-181
This paper studies different heuristics for drawing 2-level hierarchical graphs. Especially, we compare the barycenter and the median heuristics. We show that the barycenter heuristic clearly outperforms the median heuristic, although only the latter has a proved bound for the maximum error done when two vertices are ordered. Moreover, we improve a known heuristic, called the greedy switching, by introducing the barycenter heuristic as a preprocessing phase for it.  相似文献   
87.
以福建某高速公路尤溪段源湖中桥为例,阐述了中线平移互交视线测设法在斜交桥梁墩台定位的应用情况,实践证明该方法能很好地解决斜交桥梁墩台定位的问题。  相似文献   
88.
In this paper, authors investigate statistical modeling of measured mains Zero Crossing (ZC) non idealities in narrowband powerline communication systems (PLC) using time series approach based on autoregressive moving average model (ARMA). For this purpose, Box Jenkins analysis steps are deployed for detected ZC impulsive variations. Estimated models exhibit a good fit based on R-square metric reaching 90%. This modeling approach is extended to three measurement environment: in home, in lab and rural locations. Obtained models are useful for NB-PLC channel emulator implementation.  相似文献   
89.
Recently, significant efforts have been made to develop highly efficient organic light-emitting diodes (OLEDs) employing reverse intersystem crossing (RISC) owing to its capability of harvesting non-emissive triplet states. Up to date, most of such emitters were small-molecular-weight materials that needed to be doped into a host material. Due to the advantages of ease device fabrication and excellent photoluminescent properties, polymer-based RISC emitters should be developed. In this study, we reported a polyfluorene-based copolymer of poly[{9,9-dioctyl-2,7-divinylene-fluorenylene-alt-co-{2-methoxy-5-(2-ethylhexyloxy)-1,4-phenyene}] (PFOPV), which is a solution-processable, non-doped, high-molecular-weight material exhibiting RISC characteristics. A systematical magneto-electroluminescence study joint by time-resolved spectra revealed that charge transfer (CT) states would be generated between PFO and MEH-PPV components of PFOPV, and triplet CT states can participate in RISC process and contribute significantly to the emission. The PFOPV device shows excellent EL performance with EL efficiency of 12.7 cd/A and EQE of 2.2%, which is about 10–15 times and 2–4 times higher than those of PFO (0.9 cd/A, 0.63%) and MEH-PPV (1.2 cd/A, 1.1%) homopolymer devices, respectively.  相似文献   
90.
The perception of a visual target can be strongly influenced by flanking stimuli. In static displays, performance on the target improves when the distance to the flanking elements increases—presumably because feature pooling and integration vanishes with distance. Here, we studied feature integration with dynamic stimuli. We show that features of single elements presented within a continuous motion stream are integrated largely independent of spatial distance (and orientation). Hence, space-based models of feature integration cannot be extended to dynamic stimuli. We suggest that feature integration is guided by perceptual grouping operations that maintain the identity of perceptual objects over space and time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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