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91.
应用音平化渣图象分析和指导转炉造渣操作   总被引:3,自引:1,他引:2  
利用音平化渣图象可以清晰地看出在转炉造渣过程中何时发生喷溅,何时发生炉渣返干和何时化渣正常。应用音平化渣图象和炉渣三元相图,可以正确地分析发生喷溅和返干的原因,从而找到避免突发性喷溅和严重返干的方法。正确的枪位和炉渣碱度控制是实现平稳吹炼的保证,而音平化渣图象能帮助操作工实现这一目标。  相似文献   
92.
张伟  彭学军 《山东水利》2007,(4):19-19,21
依法征收河道工程维护费,是水行政主管部门的一项重要职能,是强化水利依法管理的重要手段和筹措水利建设资金的重要途径。随着依法行政进程的不断推进,被征管单位依法维权的意识不断增强。根据《行政诉讼法》的规定,人民法院审查行政案件,对具体行政行为是否合法进行审查。根据《行政复议法》的规定,复议机关审查复议案件,对具体行政行为是否合法  相似文献   
93.
Intraoperative neurological monitoring (INM) is the evaluation of the nervous system within the operating room (OR) environment. In this paper, the INM system is tested in a clinical setting in comparison with conventional somatosensory evoked potential (SEP) monitoring. The study results demonstrate the capability of the INM system in extracting clearer and more stable SEP signals. The high SNR of SEP signals collected in various clinical environments, including the OR, makes the INM system a robust platform for continuous monitoring. While the current use of EP monitoring is limited to intermittent analysis by a highly trained clinical neurophysiologist, the authors believe in changing this paradigm by developing continuous monitoring systems, such as the INM system, capable of automated quantitative EP analysis. This noninvasive monitoring modality will allow for a wider range of use in clinical practice. Based on volunteer and clinical patient studies, the INM monitoring system demonstrates much greater reliability and accuracy via the artifact rejection and denoising strategies. It provides more strategic filtering options for different situations under which the clinical SEP response signal could be greatly contaminated and distorted. Furthermore, the INM system offers a promising approach to signal extraction in real-time monitoring during SEP research.  相似文献   
94.
本文介绍了PLC(ProgrammableLogicController)在MK9卷烟机国产化改造中的应用,并提出了最大限度的用软件取代原机硬件电路提高可靠性的一种方法。  相似文献   
95.
本文根据 ALWR 的基本设计原则,初步分析了我国 AC-600反应堆压力容器的设计特点,探讨了保证 AC-600反应堆压力容器的可靠性应采取的主要技术措施.  相似文献   
96.
97.
We show that an n-vertex bipartite K3,3-free graph with n?3 has at most 2n−4 edges and that an n-vertex bipartite K5-free graph with n?5 has at most 3n−9 edges. These bounds are also tight. We then use the bound on the number of edges in a K3,3-free graph to extend two known NC algorithms for planar graphs to K3,3-free graphs.  相似文献   
98.
Spectral slope (S), describing the exponential decrease of the absorption spectrum over a given wavelength range, is an important parameter in the study of of chromophoric dissolved organic matter (CDOM) dynamics, and also an essential input parameter in remote sensing models. Furthermore, S is often used as a proxy for CDOM composition, including the ratio of fulvic to humic acids and molecular weight. The relative broad range in S values reported in the literature can be explained by the different spectral ranges and fitting methods used. A single exponential model is used to fit the S values for 17 investigations involving 458 samples in Lake Taihu from January to October in 2004. The average S value was 15.18 ± 1.39 μm−1 for the range of 280–500 nm, which fell within the range reported in the literature. The frequency distribution of S value basically obeyed a normal distribution. Significant differences in S values between summer and other seasons showed that phytoplankton degradation was one of the important sources of CDOM in summer, whereas CDOM mainly came from the river input in other seasons. Furthermore, the estimated S value decreased with increasing wavelength range used in regression. The maximum and minimum values derived from the regression were 17.89 ± 1.25 μm−1 and 13.62 ± 2.11 μm−1 for the wavelength ranges of 280–380 nm and 400–500 nm, respectively, a decrease of 23.9%. S values significantly decreased with the increase of CDOM absorption coefficients. CDOM absorption coefficients could be more appropriately estimated from exponential model introducing the variation of S with absorption coefficients, making them useful for a remote sensing bio-optical model of Lake Taihu. DOC-specific absorption coefficient a*(λ) and the parameter M describing molecular size of the humic molecules could also be used as a proxy for the sources and types of CDOM. A general relationship was found between S and a*(λ), and M values. S increased with the decrease of DOC-specific absorption coefficient and the increase of M corresponding to the decrease of molecular weight.  相似文献   
99.
The current study aims to provide fundamental insight into the behavior of microstructures containing grain sizes that span multiple length scales. A commercial 5083 Al alloy was selected as the material of interest to facilitate comparison with recently published data. The materials studied here were prepared via the thermal consolidation of powders that were cryomilled for different times (i.e., 0, 2, 4, and 8 hours). Following consolidation, the resultant microstructure was characterized by an equiaxed grain morphology with a size distribution centered around 200∼300 nm. Dispersed among the 200- to 300-nm grains were coarse-grained regions or ligaments with a grain size ranging from 600 nm to 2 μm. The occurrence of coarse-grained regions is rationalized on the basis of recrystallization or subgrain coarsening, whereas the occurrence of equiaxed fine regions is proposed to be a result of continuous grain growth. Two types of microstructures were selected for study, containing coarse-grained volumes of approximately 28 pct and 43 pct that corresponded to an ultimate tensile strength (UTS) of 566 MPa and 535 MPa, and a fracture strain of 3.2 pct and 3.5 pct, respectively. The observed ductility and the relevant toughening mechanisms were discussed in light of the presence of multiple length scales.  相似文献   
100.
吸入短寿命氡子体动物肺组织剂量与体重关系的探讨   总被引:1,自引:1,他引:0  
本文介绍吸入短寿命氡子体的不同种动物肺组织吸收剂量与体重的关系。实验结果表明,吸收剂量随体重的增加而减小。  相似文献   
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